ARTICLE XV - Beta Blockers – An Answer to All Problems!

The drug that is closest to the heart of cardiologists and most widely prescribed for a variety of indications. Literally responsible for saving millions of lives every year and making people survive through the painful angina and even drag them out of the hopelessness of myocardial infarction. The drug that is used most extensively for high blood pressure and which has given a new lease of life to patients with cardiac failure. The drug that is being used for anxiety and migraine in millions of patients in the general practice – this drug is called BETA BLOCKER.

Let’s explore the role of this group in many cardiac problems starting from high blood pressure to heart failure and heart attack.

HYPERTENSION AND BETA BLOCKERS:
Beta-blockers makes the heart beat more slowly and less strongly. They work by blocking the action of nerves supplying the heart that release a chemical called Noradrenalin. This helps to control the rhythm and force of heart muscle movement. It also effects and tones down the central sympathetic activity. Beta blockers have been in the forefront of antihypertensive arsenal for the last two decades. They have been shown to be highly effective in reducing systolic and diastolic blood pressure specially in persons with high sympathetic drive or who are tense. They are effective in reducing total death rate, strokes and kidney failure in patients with high blood pressure. Beta blockers can effectively reduce the thickness of muscle of heart due to high blood pressure. Beta blockers are well tolerated by a majority of patients and have been found to very safe in all age groups and both genders. They have a special role to play in patients with compelling indications like angina, heart attack, and heart failure. This is the only group of drugs to show reduction in heart attacks in white, non smoker males.

Being highly effective drugs with extremely safe profile, the group has earned a special place, for itself in the drugs used for hypertension. These are the most commonly used and often the drug of first choice for this indication.

ANGINA AND BETA BLOCKERS
The commonest presentation of Coronary artery disease – when a person develops blockages in the blood supply of heart, is angina. Physical or mental stress leads to increasing heart rate and blood pressure, which leads to chest pain called angina. Beta-blocker slow the heart rate and reduce the heart’s workload. When the heart does not have to work as hard, it requires less oxygen. This in turn can help relieve or prevent chest pain (angina). To treat and prevent these pains, beta blockers have proved to be very effective. Beta-blockers are often used with the medications to treat angina. Beta blockers are the drugs of first choice in most patients presenting with angina. There is ample data to support its role in angina where it decreases the frequency of angina episodes and increase effort tolerance/ exercise capacity. The severity of anginal attacks decreases markedly with Beta blockers.

Role of beta blockers in Heart attack:
Heart attack is a common presentation of coronary heart disease. Here the blood supply to a part of heart blocks completely causing death of that portion of heart. There are two ways to approach a patient with myocardial infarction. The first one is opening the blockages in arteries to re-initiate blood going to the heart, the other one is decreasing the demand of blood supply to muscles of heart and this is what this magical drug does. Beta blockers have been shown to reduce the size of myocardial infarct – dead portion of heart in animal and human models. Beta blockers reduce lipolysis, that is the break down of fats. Beta-blockers given within hours of the start of a heart attack reduce both the risk of death and recurrent heart attack. They have well established anti-ischemic, anti-arrhythmic and anti-hypertensive effects. Large trials have shown impressive reduction of morbidity and mortality with oral and intravenous beta blockers. Evidence strongly suggests that most people should take beta-blockers for at least 6 months and may be two years after a heart attack, and probably longer to get the most benefit. It applied to both genders regardless of age. It is a must for all those who suffer from hypertension. The intake is oral and should be taken continually for about two years. Almost all drugs show similar effects, although water soluble beta blockers have a clear advantage over others. But for people who have asthma and hypotension, this drug is not recommended, however controlled diabetes is not a contraindication to beta blockers as the benefits outweigh the hazards.

Role of Beta-Blockers in Heart Failure
Heart failure is a significant public health problem effecting 15 million people world wide. There has been an increasing incidence of heart failure in contrast to the decreasing incidence of heart diseases. The associated hazards as found in Framingham study, mortality rate 17% in one year, 30% in two years and 50% in five years.

For the past 40 years medical students have been taught to avoid Beta Blockers in heart failure. Beta Blockers work by blocking adrenaline which increases force of contraction of heart muscle and improve its performance. Beta blockers are like double edged sword. Due to their negative effects on heart rate and contractility, they can worsen the heart failure but, used properly and judiciously they ameliorate the patients status and have salutary effects on the clinical status, exercise capacity and reduce death rate. This has been one of the most wonderful ‘rediscovery’ of the effects of beta blockers. This is also an example of how clinical experience and experimentation can alter the course of action and carve new place.

Many large trials have been conducted to evaluate the efficacy of beta blockers in large populations with mild, moderate and severe heart failure and patients with left ventricular dysfunction after a heart attack. There was a definite and marked reduction in mortality. All cause mortality and hospitalization was reduced significantly. Hospitalization due to any cause was reduced markedly.

Who are the patients that will benefit from beta blockers therapy? All patients with mild, moderate or severe but compensated heart failure on standard treatment of ACE Inhibitors and diuretics are candidates for beta blockers. There are important points to be kept in mind as only stable patients should start beta blockers. Preferably, doses should not be changed of ACE Inhibitors for one month and diuretics for 2 weeks. Ideally patients should not have required intravenous supporting drugs in the last one month.

This is an exercise that requires persistence and patience! One has to start with a very small does and then the dose has to be increased very slowly over weeks while monitoring heart failure status, blood pressure and heart rate. Some patients may deteriorate initially, that is why persistence is very important and patients have to be encouraged to adhere to the therapy. Many patients may not see any change in their clinical status initially that is why patience is required and patients have to be motivated to hold on to the treatment.

Various trials have now documented that Beta Blockers used carefully reduce heart failure symptoms and improve the quality of life. Beta blockers have been shown to reduce the risk of all cause mortality, such as sudden death and death from progression of heart failure. Beta blockers have been effective in reducing hospitalization. Compelling evidence now exists to support the safety and efficiency of Beta Blocker therapy in heart failure.

What are the specific side effects? Patients may complains of fatigue, slow heart rate and low blood pressure. Speciation caution has to be exercised in patients with reactive airway disease and decompensated stated.

Tachycardias:
Many patients with structurally normal heart have the propensity to develop very fast beating of heart – tachycardia, presenting as palpitations, fluttering or loss of consciousness in severe cases. Because of their effects on sinus node and AV node – two important pulse generators, this fast beating can be effectively controlled. The drug may be used intravenously for immediate effects and it is effective in most cases. It is used in oral preparation for the prevention of further attacks.

Other cardiac problems:
Beta blockers have found an application in many other fields.

· It is used to relieve the obstruction in patients presenting with severe outflow obstruction like right pumping chamber outflow obstruction.
· It is effective in reducing heart rate where patient has very fast heart rate specially accompanied by obstruction like narrowing of the valve – door between left storing and pumping chambers.
· It is used effectively in reducing rapid and powerful contraction in patients with markedly thickened interventricular septum called hypertrophic obstructive cardiomyopathy HOCM.

Miscellaneous:
There was a time when newer indications were found for the usage of beta blockers every week. The drug was tried and many times quite successfully in many scenarios outside the world of cardiology.

· The drug alleviates anxiety and are used by many for allaying anxiety in stressful situations like presentations, examinations and speeches. They do not impair intellectual powers but reduce the ‘fast beating’ of heart and the unwanted ‘tremors’ and ‘cold sweat’. These drugs are used extensively by psychiatrists, all over the world, for reducing anxiety and counter the tachycardic effects of some drugs.
· They are used for tremors – mainly senile tremors.
· Many people with migraine (headaches) have been able to reduce the severity and frequency of episodes.
· Beta blockers are used in patients with liver disease like Cirrhosis for reduction of pressure in liver.
· They are used in patients with thyroid gland hyperactivity called thyrotoxicosis for controlling their symptoms.

Side Effects
Like all potent drugs beta blockers have side effects and pros and cons have to be weighed for all clinical conditions and patients. Side effects of beta-blockers may include lack of energy or drive, fatigue, vivid dreams and erection problems (impotence). It can decrease blood flow to fee and hands, causing them to feel cold and increase leg pain brought on by exertion (intermittent claudication). May cause dizziness and lightheadedness, more likely to occur when started or when the dose is increased. In people with diabetes, beta-blockers can insignificantly increase blood sugar levels. More importantly beta blockers may mask warning signs of low blood sugar, such as increase in pulse rate and sweating. Beta-blockers may worsen medical conditions such as asthma, heart failure, and certain heart arrhythmias. Beta-blockers should not be stopped without first discussing with the doctor. The risk of heart attack may be increased when beta-blockers are stopped suddenly.

Beta blockers are drugs with multiple actions and have been used in many cardiac diseases like high blood pressure, angina, heart attack and heart failure. They have wide-spread applications in non cardiology world. By and large they are well tolerated and have certain side effects which have to be watched.

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Ref: Heal Thy Heart written by Prof: Dr. Muhammad Hafizullah

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ARTICLE XII - How to pass the ‘Failed Heart’ (Part-I)

“No, this is not possible, I cannot have heart failure,” said Abdul Qayyum, 50 years old bureaucrat with clenched fists and raised eyebrows. His argument were, “I can walk around and attend my office, so I cannot be too unwell!”It took him some time to accept the diagnosis. His next question was, “Is it the end of story? Shall I ask for retirement and confine my activities?” He was very happy to learn that firstly, heart failure was not synonymous with cardiac arrest/death and secondly, near to normal life was possible with new medical treatment. Some new drugs have effects on improving the outlook of disease and new technology is evolving to mitigate the suffering of patients with heart failure.

Heart failure is the end result of many diseases that effect the heart. Some diseases effect muscles of heart either through infections or deprivation of blood supply – coronary artery disease. Certain diseases effect the doors of heart called valves, either by restricting their motion or rendering them incompetent and leaky. High blood pressure puts extra load on heart and heart muscle has to generate higher pressure to pump blood. This extra effort taxes heart and eventually leads to heart failure. Heart tries to compensate by either beating fast or increasing in size, but eventually gives in. This stage is called heart failure as heart cannot meet the demands of body.

For the management of heart failure, prompt and accurate diagnosis of the disease causing heart failure is of paramount importance. There are several causes of heart failure. Several different tests are required to determine the exact cause of heart failure. In some cases the cause of heart failure can be reversible (such as a heart valve defect) or treatable (such as a thyroid problem) but in a majority of cases drug treatment is used to reduce the symptoms and improve the outlook.

How to work up heart failure? In patients with symptoms suggestive of heart failure, many tests may be required. Recently there has been a lot of research on a special blood test called brain natriuretic peptide (BNP), which can be used to diagnose heart failure and correlates well with severity of failure. The level rises when heart failure worsens. Electrocardiography (ECG) and Chest X-ray are the bare minimum cardiac tests. Echocardiography (echo) is the best and simplest way to determine heart function and whether it is systolic or diastolic heart failure. Echocardiography can also help to determine the cause of heart failure and help guide treatment decisions.

Nuclear scanning – a non invasive nuclear test is done to identify areas of the heart that are not receiving adequate blood flow (ischemic areas) and assess the left ventricle’s ability to function. Cardiac blood pool scan (radionuclide ventriculography) is often used when echocardiography results are less likely to be accurate due to a person’s weight or breast size of the presence of severe lung disease. Radionuclide ventriculography provides an accurate method for assessing the pumping ability of the left ventricle. However, it is less useful for evaluating the presence of heart valve disease and thickening of the heart muscle. ThalliumRadionuclide ventriculography provides an accurate method for assessing the pumping ability of the left ventricle. However, it is less useful for evaluating the presence of heart valve disease and thickening of the heart muscle. ThalliumRadionuclide ventriculography provides an accurate method for assessing the pumping ability of the left ventricle. However, it is less useful for evaluating the presence of heart valve disease and thickening of the heart muscle. Thallium/MIBI scan can detect reduced blood flow to heart. Cardiac catheterization and angiography can be used to identify blocked or narrowed coronary arteries and to measure pressures inside heart. Test results can help diagnose conditions that might cause or worsen heart failure symptoms.

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Ref: Heal Thy Heart written by Prof: Dr. Muhammad Hafizullah

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ARTICLE XI - So you had a Heart Attack – What next!

Khalid seemed visibly upset and was trying to hold back his tears. He was in his early forties and had just entered his pratical life. He had two small kids and a very lucrative job. He had many dreams and many unfulfilled plans. He was perfectly healthy so far and it had not occurred to him in his wildest dreams that he will end up in CCU one day. But as luck would have it, he suffered a heart attack one morning, and here he was in CCU on the second day of his admission.

I could see a hot of questions written all over his face. Is it the end of his career and will he lead a nearly crippled life? Does it imply that he will be confined to his house for the rest of his life? Does it mean that he necessarily has to go for a bypass operation< Will he not be able to enjoy golf again? Does he have to remain content with a boiled diet without any meat? Should he pursue his MBA degree? Should he still consider an addition in his family?

Heart attack can mean different things to different people. For most patients it is an important event but it passes off like another event and the person can go back to normal life. There is a definite mortality attached to it. Half of the persons who die of heart attack die within first hour and that too because of irregular beating of heart. In a few cases, it is not even recognized as a heart attack. Later, once patient is stable in CCU and has received definitive treatment then the death rate does down. Ninety percent of patients will leave CCU and hospital alive on their feet.

There was a time when patients were kept in the hospital for weeks and they were not allowed to lave the bed for a month. Things have changed for the better! Patients who are otherwise stable are mobilized after forty eight hours. They are discharged if they are otherwise stable on third or fourth day. If they have any problems – mechanical or electrical, they are kept under observation for as long as necessary. Patients who undergo angioplasty after heart attack may be discharged the next day and allowed to return to work much earlier. Patients are advised rest and leave from work for four weeks. Gradual mobilization is recommended after discharge. Starting from ten minutes on an empty stomach at a leisurely pace morning and evening and then building it up slowly to thirty minutes twice a day. Most patients can expect to go to work after four weeks.

When and what tests does one require after a heart attack? The basic philosophy is firstly to document the extent of damage in terms of function of left ventricle – main pump. Secondly, determine the extent of blockages in vessels supplying heart – coronary arteries, and thirdly look for all risk factors and try to improve them. Most patients will be required to undertake tests like effort tolerance test and echocardiography. This is to identify patients who will be requiring further tests like coronary angiography and hence requiring interventions like angioplasty and bypass operation. Not every patient who suffers from heart attack needs angiography or bypass surgery. Patients on very demanding and physically tough jobs or those who are young are advised coronary angiography irrespective of the result of effort tolerance test.

Big question for the family is what to allow the patient to eat? Many patients on their first visit after heart attack bring their youngest child who demands a list of forbidden food. This young lad turns out to be mama’s detective on a special duty. Depending on other risk factors like diabetes, high blood pressure and high cholesterol, there is not a lot that a patient should be denied. Preferably, food should be low in cholesterol within no ghee, butter, fat, egg, and internal organs. Small quantity of chicken and meat are allowed and fish is encouraged. No bar on bread or rice unless the patient is fat and calories have to be watched. Soups are allowed but should not replace normal food. Some roughage in the form of salad and fresh or boiled vegetables should be encouraged as it prevents constipation. Half cream or skimmed milk may be consumed. Juices especially fresh may be encouraged if the patient is not diabetic. Fresh fruits are always welcome.

Most patients are able to retain their job and follow their pursuits unless it is very risky and demanding. A few months down the lane most people will have forgotten about the event and gone back to their old life styles. Competitive sports and jobs in armed forces may be difficult to retain. Most intellectuals and bureaucrats have had a heart attack by the fifth decade but they continue to follow their jobs and hobbies.

Can one have another heart attack after the first one? Why not! So one has to put in efforts to correct one’s risk profile. For those who are diabetic, blood sugar level has to be meticulously controlled by keeping a very vigilant watch on diet and taking prescribed medicines regularly. Patients with high blood pressure have to bring their blood pressure to normal range or lower than that. Salt has to be restricted and treatment plan adhered to. Cholesterol has to be brought down regardless of the baseline levels. Strict control on diet is required and nowadays we are very liberal in prescribing cholesterol lowering drugs like statins. They have been shown very convincingly to reduce deaths and requirement of angiography and interventions like bypass and angioplasty in treated patients with salutary effects on lipid profile.

With modern treatment, like clot dissolving drugs and angioplasty – opening of vessels with balloons and stents, the outlook has improved remarkably. Most patients can go back to their original job and life style in four weeks. Regular exercise, discretion in diet and adherence to treatment are the golden rules to follow. For the majority of patients who sustain a heart attack, it is not the end of the world!

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Ref: Heal Thy Heart written by Prof: Dr. Muhammad Hafizullah

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Article X - Management of Heart Attack – the Recent Advances!

The immediate management of heart attack called acute myocardial infarction, entails accurate and prompt diagnosis of heart attack based on history, ECG and blood test for release of cardiac enzymes. For monitoring and definitive treatment, quick assessment and early referral to a coronary care unit (CCU) is required. Management includes general measure and drugs – pharmacotherapy. Effort has been made to describe various strategies and drugs under the headings of rationale and evidence, indications, protocol and dosage and precaution.

MOBILITY:

Patient is confined to bed for the first 24 hours being monitored in CCU. Patients with persistent chest pain, irregular beating of heart called arrhythmias or heart failure are immobilized for longer duration. In uncomplicated heart attack gradual mobilization according to a set protocol should be followed.

OXYGEN:
Rationale and Evidence
Increased oxygen concentration is helpful at the time of heart attack to protect jeopardized heart muscle. It is helpful in reducing ventilation and perfusion mismatch. Administration of 100% oxygen has been shown to reduce ECG changes and have some effect on reduction of heart attack severity and size in animal and human models.

Who should get it?
Supplemental oxygen to all patients with overt breathlessness and those who have low oxygen saturation. Routinely it may be administered to all the patients with uncomplicated heart attack during the first 2-3 hours. There is no convincing evidence of any significant benefit in uncomplicated heart attack beyond 3 hours. Oxygen may be administered by nasal prongs or mask. The rate may be adjusted in arterial desaturation guided by repeat estimation. Nasal prongs may cause nasal irritation and mask may cause claustrophobia.

PAIN KILLERS
Rationale and Evidence:
Heart attack pain is very severe and capricious accompanied with impending feeling of death. Pain increased sympathetic activity hence increasing oxygen metabolic demand. This has to be relieved in shortest possible time with effective analgesics in appropriate dosage through proper route and repeated at proper intervals.

Who should get it?
Every patient with severe chest pain with ECG evidence should receive adequate analgesics. Those patients presenting after pain resolution may not be candidates for analgesics.

Precaution:
Morphine and analogues may depress breathing and extra caution must be exercised in old patients and those with chronic chest problems. Morphine and analogues cause vomiting, so anti-emetics should be given prophylactically.

CLOT DISSOLVING TREATMENT (Thrombolytic therapy):
Rationale and Evidence:
Last decade has been the decade of clot dissolving drugs called Thrombolytics. Convincing evidence from many large trials involving large patient population has secured a steady place for Thrombolytic therapy in the management of heart attack. This has revolutionized the management of acute heart attack. There has to be a solid reason for withholding Thrombolytic therapy. Dewood studies showed that a clot is involved in hart attack in more than 85% of cases.

This aim is early, complete and sustained blood flow to heart muscle. Cloth dissolving strategy involving intracoronary and intravenous administration of various agents has eventually reached a state of consensus. Clot dissolving therapy to reperfuse reduces death rate by 21% in patients with heart attack that means saving 21 lives per 1000 patients. The effects are time dependent as evidence suggests maximal benefit within two hours, optimal within six hours though definite benefit lasts till 12 hours. An estimated 35 lives per 1000 are saved when initiated within one hour as against 16 lives per 1000 when given 7 – 12 hours after the onset of symptoms.

Who should get it?
Clot dissolving drugs benefit all patients irrespective of age, gender, and presences of other conditions like diabetes mellitus. All patient presenting with heart attack within six hours of onset of symptoms must be administered clot dissolving Thrombolytics. Patients presenting within 6-12 hours should be considered for Thrombolytics. Patients presenting with symptoms suggestive of heart attack with left bundle branch block an ECG finding, should be candidates for Thrombolysis. Patients presenting after 12 hours with persisting pain and ECG changes should be considered for reperfusion theraphy after weighing pros and cons. More aggressive approach is desirable in younger patients and those with large heart attacks. It is, however, the elderly who get more benefit from Thrombolytic therapy.
Concerted efforts should be made that maximum number of patients benefit from this therapy. Initial evaluation in casualty department and CCU should be prompt and should not take more than twenty minutes in total. Consolidated data shows that 1.6 lives can be saved per hour per 1000 patients. Time is muscle, and every effort should be made to administer Thrombolytics as soon as possible.

Precautions:
Patients with contraindications to clot dissolving thrombolytics, like active internal bleeding, history of stroke, brain tumour, suspected aortic dissection, prolonged resuscitation, proliferative retinopathy, acute pancreatitis, fixed accelerated high blood pressure and bleeding disorders should not be given Thrombolytics. Streptokinase should not be used after 7 days and before 6 months of first administration due to the presence of antibodies.

ANGIOPLASTY:
Rationale and Evidence:
Coronary angioplasty provides the distinct advantage of not only opening the occluded artery by taking care of the superimposed clot but also dilating the primary lesion. The success rate of opening the infarct related artery is 95%. With the employment of stents the results are getting better. Infarct related artery has to be opened quickly, with lower rates of acute and subacute occlusion and restenosis. A pioneer study showed higher patency rates of coronary artery with reduced morbidity and mortality rates. It can be employed as the first and only procedure called primary angioplasty. In case of failure of clot dissolving treatment it is used as a rescue procedure called rescue angioplasty. Primary angioplasty should be performed by skilled operators backed by experienced personnel.

Who should get it:
The evidence from different trials support better outcome in terms of morbidity and mortality with anagioplasty as compared to thrombolytics. This mode of reperfusion is preferable wherever the facilities and expertise are available. It is the treatment of choice for patients presenting with low blood pressure called cardiogenic shock associated with large infarcts. It is of great importance for patients who cannot receive clot dissolving thrombolytic therapy. Patients who have received thrombolytic therapy in the last six months or who are allergic to it can derive benefit from angioplasty. Patients who fail to respond to thrombolytic therapy should be subjected to angioplasty.

The time taken from reporting to hospital to inflation of balloon in patients undergoing angioplasty should be comparable to the time taken in patients receiving clot dissolving drugs. This requires prompt assessment and management in the casualty department and CCU. Quick and in time referral to the Catheterization laboratory is mandatory. Round the clock availability of skilled operators and experienced staff and a well stocked Catheterization laboratory are very essential for the success of any programme. Cardiac surgical team should be available in case of emergency.

Precautions:
This mode of reperfusion involves high cost due to high cost of catheterization laboratory and hardware involved. It is subject to the availability of highly skilled and experienced operator and staff round the clock. Very few hospitals have such facilities so this can be offered to a very small segment of society.

ASPIRIN:
Rationale and Evidence:
Very few treatment modalities have been so well and widely received and practiced as aspirin in heart attack. Aspirin in does of 40 mg can reduce the aggregation property of platelets. In a summary of 33 trials, heart attack in patients on Aspirin was reduced from 25% to 11%. Many trials have shown remarkable beneficial effect.

Who should get it?
Every patient with no contra-indication to aspirin should be given aspirin as soon as possible. Administration of beta blocker, ACE inhibitors, reperfusion with thrombolytic therapy or primary PTCA, presence of hypotension, hypertension, bundle branch block, complete heart block, diabetes pose no contraindication to aspirin.

Every patient with suspicion of heart attack should be given aspirin 300 mg to chew as soon as possible and continued indefinitely in dosage of 75 mg per day. Various enteric coded brands are available in the market to reduce hyperacidity.

Precautions:
Patients with proven ulcer on endoscopy or barium meal, history of gastic bleeding or those receiving antiulcer treatment should not be given aspirin. Patients with known allergy should not be given aspirin. Other platelet inhibitors may be considered in patients who have allergy or who cannot tolerate aspirin.
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VESSEL DILATOR – NITRATE:
Rationale and Evidence:

Nitrates have muscle relaxation effect hence causing dilation of all vessels. This causes reduction in load on heart hence reducing oxygen demand. Intravenous therapy has been shown in animal and human models to reduce infarct size.

Who should get it?
Patients presenting, with heart attack in the first 24-48 hours, specially in large anterior heart attack, persistent chest pain and high blood pressure. It may be continued beyond 48 hours in patients with persistent chest pain or recurrent angina and breathlessness. Routine use after 24-48 hours is not recommended.

Nitroglycerine or Nitrate infusion is started and titrated while monitoring heart rate and blood pressure. Blood pressure reduction by 10% or heart rate increase by 10% should warrant reduction in dosage and closer monitoring. Long term oral therapy has not been found to have any significant effect on morbidity and mortality.

Precautions:
Patients presenting with blood pressure less than 90 mmHg, or slow heart rate should not be given Nitrate infusion. Lowering of blood pressure and increase in heart rate should be closely monitored.

BETA BLOCKERS:
Rationale and Evidence:
Beta blockers reduce heart rate and contractility hence decreasing oxygen demand. This has been shown to reduce heart attack size in animal and human models. Beta blockers decrease fatty acids. They have a well established role in ischaemia – reduce blood supply, arrhythmia – irregular heart beating and high blood pressure. Large trial and meta analysis have shown impressive reduction of morbidity and mortality with oral and intravenous beta blockers.

Who should get it?
Every patient regardless of age, gender, reperfusion strategy and therapy, time period, type of heart attack, associated comorbid condition should get it. It is of particular importance in patients with recurring chest pains, fast heart rate and high blood pressure.
Evolving heart attack should be given intravenous beta blocker watching blood pressure and heart rate closely. Oral therapy in appropriate dosage should be instituted at the earliest and continued preferably for two years. Perhaps all beta blockers in proper dosage confer similar effects. Beta blockers with longer half life have the advantage of convenience of dosage and lesser side effects.

Precautions:
Patients with asthma, chronic chest problems, low blood pressure – hypotension, overt heart failure, slow heart rate, uncontrolled or brittle diabetes should not be given beta blockers. Mild heart failure may be challenged with beta blockers under close supervision. Controlled diabetes is not a contraindication to beta blockers as the benefits outweigh the hazards.

ACE INHIBITORS:
Rationale and Evidence:
Dead – infracted segments stop contracting following a heart attack, other segments become hyperactive to maintain heart function. Heart undergoes remodeling in which it enlarges in size with increased wall tension on non infracted segments. Studies have shown that higher volumes are associated with higher chances of heart failure and increased morbidity and mortality. ACE inhibitors (ACEI) have been shown to reduce load on heart hence reducing wall tension and help is not increasing heart volumes. Use of ACE inhibitors in patients with symptoms of heart failure or evidence of reduced function derive maximal benefit with significant reduction of mortality and morbidity as shown in many large well conducted trials.

Who should get it?
All patients without contra indications to ACE inhibitors should be considered for it. It is particularly helpful in patients with symptoms and signs suggestive of heart failure or who have evidence of heart dysfunction – large dimensions and poor contraction even in absence of symptoms.

ACE inhibitors should be started with small dosage to obviate any low blood pressure episodes. The dose has to be built up gradually if patient can tolerate it. Systolic blood pressure should be mentioned closely. Optimal effects can only be expected at appropriate dosage Determined efforts should be made to optimize the dosage during hospitalization.

Precautions:
Patients with systolic blood pressure less than 90 mmHg should not be given ACEI. Those showing marked decrease in blood pressure, ACEI should be withheld and restarted at small dosage after some time. Those having persistent cough or intolerance to ACEI may be considered for Angiotensin receptor blockers like Losartan, Valsartan, Candesartan etc.

ANTI COAGUTANT – HEPARIN:
Rationale and Evidence:
Clot dissolving Drugs can open up the infarct related artery but for sustained patency Heparin had been advocated for a long time. Recent evidence from a large trial analysis does not support the regular use of Heparin following Streptokinase unless patient is at high risk for clot formation and dislodgement. Those patients who do not receive Thrombolytics may derive some benefit from Heparin. In the setting of unstable angina, intravenous Heparin has been shown to reduce morbidity and mortalilty.

Who should get it?
Patients presenting with unstable angina should get Heparin. Patients presenting late for thrombolytics should be considered for Heparin. In patients at high risk for clot formation and dislodgement like large or anterior infarction, irregular heart beat, or left ventricular clot, intravenous Heparin is preferred. Intravenous (IV) Heparin in patients receiving selective thrombolytics like tpa or alteplase is recommended.

Precaution:
Strick regimen should be followed as under dosage leads to treatment failure and overdosage causes bleeding complications.

FURTHER MANAGEMENT
This depends on the further course of disease. Uncomplicated heart attack patients are mobilized and discharged on 4th to 7th days of admission. An exit exercise tolerance test is favoured by some groups to identify patients at high risk requiring early angiography and intervention. Any mechanical, electrical or ischaemic complication is dealt with according to its merit.

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Ref: Heal Thy Heart written by Prof: Dr. Muhammad Hafizullah

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Article VIII - Put a Leash on the Silent Killer – High Blood Pressure

“Doctors are lowering the goal post every few years, what was desirable a few years ago has become unacceptable now,” commented Ansaar, a patient of high blood pressure for the last ten years, as I drew his attention to the new targets of blood pressure. “Initially I was told that blood pressure of 160/90 is the goal and now I am being told that it is too high,” he continued. I tried to explain, “New research has established that the risk of heart disease has a continuous relationship with blood pressure and there is no safe lower limit. We have recognized that lower blood pressure accrues more benefits for the patient with reduction in death rate and lesser complications pertaining to heart, brain, eyes and kidneys.”

The aims of blood pressure treatment are to reduce cardiovascular diseases like heart attack, angina and stroke and reduce and prevent kidney related complications and deaths. This is achievable by aiming to treat blood pressure to less than 140/90 mmHg in general population and less than 130/80 mmHg in patients with diabetes or chronic kidney disease. It is important to achieve systolic blood pressure goal, especially in persons more than 50 years of age.

It is important to take steps to keep blood pressure under control. How to control elevated blood without resorting to drugs? In this section we will learn about blood pressure-lowering lifestyle habits and blood pressure medications.

1. Lifestyle:
Adopting healthy lifestyle habits is an effective first step in both preventing and controlling high blood pressure. Physical activity is perhaps the best way to counteract high blood pressure. It helps to reduce weight, lowers cholesterol and hence the risk of heart disease. If lifestyle changes alone are not effective in keeping the pressure controlled, it may be necessary to add blood pressure medications.

2. Reduction of salt:
A key to healthy eating is choosing foods low in salt and sodium. Most people consume more salt than they need. The current recommendation is to consume less than 2.4 grams (2,400 milligrams) of sodium a day. That equals 6 grams (about 1 teaspoon) of table salt a day. This includes all salt and sodium consumed, including that used in cooking and added at the table. For someone with high blood pressure, the advice is to eat less salt and sodium. Recent research has shown that people consuming diets of 1,500 mg of sodium have lower blood pressure. The lower-sodium diets prevent blood pressure from rising and help blood pressure medicines work well.

3. DASH Diet.
A diet known as Dietary Approaches to Stop Hypertension (DASH) is now recommended as an important step in managing blood pressure. This diet is not only rich in important nutrients and fiber but also includes foods that contain more electrolytes, potassium, calcium, and magnesium, than are found in the average diet.

Avoid saturated fat although include calcium-rich dairy products that have no or low-fat. When choosing fats, select monounsaturated oils, such as olive or canola oils. One study reported a reduced need for anti-blood pressure drugs in people with a high intake of virgin olive oil, but not sunflower oil a polyunsaturated fat.

Choose whole grains over white flour or pasta products. Choose fresh fruits and vegetables every day. Many foods are rich in fiber, which may help lower blood pressure. Important foods include most fruits (especially potassium-rich fruits including bananas, and oranges) and vegetables (especially carrots, spinach, mushrooms, beans, potatoes), includes nuts, seeds, or legumes (dried beans or peas).

Choose modest amounts of protein (preferably fish, poultry, or soy products). Soy in combination with fiber-rich foods or supplements may have specific benefits. Oily fish may also be particularly beneficial. They contain omega-3 fatty acids, which have been associated with heart and never protection.

In one study, after eight weeks on the diet, subjects from a broad range of backgrounds, experienced a significant reduction in blood pressure. Evidence now also suggests that it may be a good diet for lowering LDL cholesterol levels – although the beneficial HDL levels also decline.

4. Weight Loss
Weight gain seems to be a primary determinant in blood pressure increase, and weight loss may be even more important than salt restriction in controlling blood pressure. Losing weight, particularly in the abdominal area, immediately reduced blood pressure. Weight loss, particularly accompanied by salt restriction, may allow patients with mild hypertension, even older people, to safely reduce or go off medications. The benefits of weight loss on blood pressure appear to be durable.

5. Stress Reduction and Psychological Therapy
Improving mood or relieving stress may be helpful. The following are some studies suggesting possible benefits:

Two small studies reported that active religious faith was associated with healthy blood pressure levels, possible indicating the combined benefits of a strong social network and reduced stress from spiritual activities.
Studies suggest that stress reduction programs, such as those that use cognitive-behavioral therapy, can reduce blood pressure. In some cases people can even go off medication.
Even pets can provide healthful support. In a small 2001 study, medication had no effect on blunting blood pressure that increase in response to stress, but owning a pet did.
In another study, a simple relaxation technique called transcendental meditation (TM), which involves silent repetition of a single sound, was shown to be effective in reducing blood pressure. This is equivalent to our Tasbeehat which we ought to offer regularly.

6. Drugs:
If above measures are unable to normalize blood pressure, then one has to resort to drugs. Here is brief description of main types of drugs and how they work, their benefits and main side effects. Often, two or more drugs work better than one.

1. Diuretics
Diuretics are called “water pills” because they work in the kidneys and flush excess water and sodium from body. For decades, diuretics, have been the mainstay of antihypertensive therapy and are still considered the first choice by many experts.

Benefits of Diuretics. Diuretics significantly reduce the risk for stroke; they may in fact be the most important agent for preventing brain attack. They also appear to protect against stroke in people without high blood pressure. They are associated with a lower risk for heart attack (although this not as significant as their protection against stroke).
Diuretic Types. Diuretics are available in many types and are generally inexpensive. Most need to be taken once a day. Three primary types of diuretics are:

Thiazides. Thiazides are most frequently used and most effective agents for the treatment of high blood pressure. They may either be taken alone for mild to moderate hyper-tension or used in combination with other types of drugs.

Loop diuretics. Loop diuretics block sodium transport in parts of the kidney; they act faster than Thiazides and have a great diuretic effect. It is important to use the medication cautiously and avoid dehydration and potassium loss.

Potassium sparing agents. These diuretics conserve potassium. Potassium-sparing diuretics include Amiloride, and Spironolactone.

· Side Effects and Problems:
The loop and Thiazide diuretics deplete the body’s store of potassium, which, if left untreated, increases the risk for arrhythmias. Arrhythmias are heart rhythm disturbances that can, in rare instances become serious. As such, we either prescribe low dose diuretic, recommend potassium supplements, or use potassium-sparing diuretics in combination. Potassium-sparing drugs have their own risks, which include dangerously high levels of potassium in people with existing elevated levels of potassium or in those with damaged kidneys. However, mild diuretics are well tolerated and in general diuretics are more beneficial than harmful.

Common side effects of diuretics are fatigue, depression, irritability, urinary incontinence, loss of sexual drive, breast welling in men, and allergic reactions. Diuretics can trigger attacks of gout. Diuretics may raise cholesterol level marginally.

2. Beta-Blockers
· Benefits: They affect the force and frequency of heart beats, slow certain metabolic processes and ease the workload of heart. They are very effective in reducing blood pressure and have been associated with the reducing the number of deaths from heart diseases. They have an added advantage in patients with high blood pressure, angina and hyper dynamic circulation.
· Side Effects and problems:
Because they can constrict bronchial airways, patients with asthma, emphysema, and chronic bronchitis should avoid them. Beta blockers should be used with caution in patients with poor heart function, and those who have heart failure. As they can reduce heart rate so patients with slow heart rates should not be prescribed beta blockers. Fatigue and lethargy are the most common psychological side effects. Some people experience vivid dreams and nightmares, depression, and memory loss. Dizziness and lightheadedness may occur upon standing. Exercise capacity may be reduced. Other side effects may include coldness of extremities that is, legs and toes, arms and hands. Angina, heart attack, and even sudden death have occurred in patients who discontinued treatment without gradual withdrawal.

3. Angiotensin Converting Enzyme Inhibitors
They are the first line drugs and are being prescribed most commonly for blood pressure. Angiotensin converting enzyme (ACE) inhibitors block the effects of the angiotensin-renin-aldosterone system, which is though to have many harmful effects on heart and blood vessels.

· Benefits: They may be very important agents for patients with diabetes. They may help protect kidneys and heart of these patients, independently of their effect on blood pressure. They may help prevent changes in heart muscle cells leading to heart failure, specifically in reducing enlargement of the left side of the heart, a major risk factor for heart failure. ACE inhibitors can improve a patient’s odds of surviving a heart attack.

· Side effects and problems:
Major side effect of ACE inhibitors is severe persistent irritating cough. This cough does not respond to any medication except for cessation of the drug. Although ACE inhibitors can protect against kidney disease, they also increase potassium retention in kidneys. This increases the risk for cardiac arrest if levels become too high. Because of this action, they are not generally given with potassium-sparing diuretics of potassium supplements.
Side effects include excessive drops in blood pressure, and allergic reactions.

4. Vasodilators
Vasodilators, which widen/dilate blood vessels, are often used in combination with a diuretic or a beta-blocker. They are rarely used by themselves. Some of these drugs should be used with caution or not at all in people with angina or who have had a heart attack.


5. Calcium Channel Blockers
Calcium channel blockers, or calcium antagonists, have an immediate effect on reducing blood pressure. Studies continue to report that they are equally effective or better than other anti-hypertensive agents in preventing heart events, stroke, or kidney complications. Recent research support their positive role in reducing death and complication rate as compared to other classes of drugs.

· Benefits: Calcium channel blockers are effective and safe. They are used in preference in patients with angina. Certain Calcium channel blockers have a useful role in controlling arrhythmias. They are very well tolerated and have no serious side effects.
· Side Effects and problems.
Side effects vary among different preparations. Most drugs can cause fluid accumulation in feet, along with constipation, fatigue, impotence, gingivitis, flushing, and allergic symptoms. Interactions with drugs also differ depending on the drug. For example, Verapamil and Diltiazem interact with Digoxin, but Dihydropyridines do not.

6. Angiotensin – Receptor Blockers
Drugs known as angiotensin-receptor blockers (ARBs), also known as angiotensin II receptor antagonists, are similar to ACE inhibitors in their ability to lower blood pressure.

· Benefits: ARBs may have fewer or less severe side effects, including cough. Recent studies have documented that ARBs protect the heart and kidneys as were benefits found with ACE inhibitors. Many comparison studies are underway. In a very promising study, the ARB Losartan reduced the risk of heart attack, death, and stroke more effectively than the beta blocker Atenolol. This is the first study finding any drug superior to a beta blockr for achieving these results. They may even improve quality of life when added to a drug regimen—a finding also found with no other anti-hypertensive drugs.
· Side effects and problems: The side effect profile is benign and most patients tolerate the drug very well. Though initially the drug was very expensive and out of reach of most people, it is now available at comparable cost.

7. Alpha Blockers
Alpha blockers widen arterioles and veins and thereby reduce blood pressure. They are recommended for reducing blood pressure along with other agents, as their side effects profile is benign.

8. Combinations:
To achieve desirable reduction in blood pressure different groups of drugs may be combined. Adding different drugs add the effects and decrease the side effects attached to higher dosage. New guidelines have issued clear directive to start therapy with two agents, if blood pressure is considerably higher than the target blood pressure.

High blood pressure is a common disease afflicting a large population. It has been termed as a silent killer as it can be asymptomatic in spite of effecting target organs. Life style modifications should be employed in the start but drugs can be added if desirable effects are not achieved.

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Ref: Heal Thy Heart written by Prof: Dr. Muhammad Hafizullah

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