Types of high blood pressure medication.

Diuretics sometimes called “water pills” prevent heart attacks and strokes. Many people with diabetes or kidney disease take diuretics. Hydrochlorothiazide and furosemide are examples of commonly prescribed diuretics.

Beta blockers prevent heart attacks and strokes in people younger than 60. Beta blockers are very important medicines that are commonly used in patients with heart disease.

ACE inhibitors (Angiotensin converting enzyme inhibitors) prebent heart attacks and strokes. ACE inhibitors are commonly used in patients who have hypertension and heart disease. They are also recommended for people with diabetes or kidney disease.

ARBs (Angiotensin receptor blockers) prevent heart attacks and strokes. They are often recommended for people with diabetes or kidney disease.

CCBs (Calcium channel blockers) prevent heart attacks and strokes.

Direct Renin inhibitors. In 2007 the first direct rennin inhibitor (aliskiren) was approved for use in Canada. Aliskiren lowers blood pressure to a similar extent as other antihypertensive drugs but studies to examine its effectiveness at preventing heart disease and strokes are not yet complete.

 

 

HEART ATTACK

A heart attack also known as a myocardial infarction is the death of the heart muscle from the sudden blockage of a coronary artery by a blood clot. Coronary arteries are blood vessels that supply the heart muscle with the blood and oxygen. Blockage of a coronary artery deprives the heart muscle of blood and oxygen causing injury of the heart muscle. Injury of the heart muscle causes chest pain and chest pressure sensation. If blood flow is not restored to the heart muscle within 20 to 40 minutes irreversible death of the heart muscle will begin to occur. Muscle continues to die for 6 to 8 hours at which time the heart attack usually is “complete”. The dead heart muscle is eventually replaced by scar tissue.

Approximately 1 million Americans suffer a heart attack each year. Four hundred thousand of them die as a result of their heart attack.

What causes a heart attack?

Atherosclerosis. It is a gradual process by which plaques (collections) of cholesterol are deposited in the walls of arteries. Cholesterol plaques cause hardening of the arterial walls and narrowing of the inner channel (lumen) of the artery. Arteries that are narrowed by atherosclerosis cannot deliver enough blood to maintain normal function of the parts of the body they supply. For example, atherosclerosis of the arteries in the legs causes reduced blood flow to the legs. Reduced blood flow to the legs can lead to pain in the legs while walking or exercising, leg ulcers, or a delay in the healing of wounds to the legs. Atherosclerosis of the arteries that furnish blood to the brain can lead to vascular dementia (mental deterioration due to gradual death of brain tissue over many years) or stroke (sudden death of brain tissue).

In many people atherosclerosis can remain silent (causing no symptoms or health problems) for years or decades. Atherosclerosis can begin as early as the teenage years but symptoms or health problems usually do not arise until later in adulthood when the arterial narrowing becomes severe. Smoking cigarettes, high blood pressure, elevated cholesterol, and diabetes mellitus can accelerate atherosclerosis and lead to the earlier onset of symptoms and complications particularly in those people who have a family history of early atherosclerosis.

Coronary atherosclerosis (or coronary artery disease) refers to the atherosclerosis that causes hardening or narrowing of the coronary arteries. Diseases caused be the reduced blood supply to the heart muscle from coronary atherosclerosis are called coronary heart diseases (CHD). They include heart attacks, sudden unexpected death, chest pain (angina), abnormal heart rhythms, and heart failure due to weakening of the heart muscle.

Atherosclerosis and angina pectoris. Angina pectoris (also referred to as angina) is chest pain or pressure that occurs when the blood and oxygen supply to the heart muscle cannot keep up with the needs of the muscle. When coronary arteries are narrowed by more than 50 to 70 percent the arteries may not be able to supply of blood to the heart muscle during exercise or other periods of high demand for oxygen. An insufficient supply of oxygen to the heart muscle causes angina. Angina that occurs with exercise or exertion is called exertional angina. In some patients especially diabetics the progressive decrease in blood flow to the heart may occur without any pain or with just shortness of breath or usually early fatigue.

Exertional angina usually feels like a pressure, heaviness, squeezing, or aching across the chest. This pain may travel to the neck, jaw, arms, back, or even the teeth and may be accompanied by shortness of breath, nausea, or a cold sweat. Exertional angina typically lasts from 1 to 15 minutes and is relieved by rest or by taking nitroglycerin by placing a tablet under the tongue. Both resting and nitroglycerin decrease the heart muscle’s demand for oxygen thus relieving angina. Exertional angina may be the first warning sign of advanced coronary artery disease. Chest pains that last a few seconds are rarely due to coronary artery disease.

Angina can also occur at rest. Angina at rest more commonly indicates that a coronary artery has narrowed to such a critical degree that the heart is not receiving enough oxygen even at rest. Angina at rest infrequently may be due to spasm of a coronary artery (a condition called Prinzmetal’s or variant angina). Unlike a heart attack there is no permanent muscle damage with either exertional or rest angina.

Atherosclerosis and heart attack. Occasionally the surface of a cholesterol plaque in a coronary artery may rupture and a blood clot forms on the surface of the plaque. The clot blocks the flow of blood through the artery and results in a heart attack. The cause of rupture that leads to the formation of a clot is largely unknown but contributing factors may include cigarette smoking or other nicotine exposure, elevated LDL cholesterol, elevated levels of blood catecholamines (adrenaline), high blood pressure, and other mechanical and biochemical forces.

Unlike exertional or rest angina heart muscle dies during a heart attack and loss of the muscle is permanent unless blood flow can be promptly restored usually within 1 to 6 hours.

While heart attacks can occur at any time more heart attacks occur between 4.00 A.M. and 10.00 A.M. because of higher blood levels of adrenaline released from the adrenal gland during the morning hours. Increased adrenaline as previously discussed may contribute to rupture of cholesterol plaques.

Approximately 50% of patients who develop heart attacks have warning symptoms such as exertional angina or rest angina prior to their heart attacks but these symptoms may be mild and discounted.

What are the symptoms of a heart attack? Although chest pain or pressure is the most common symptom of a heart attack, heart attack victims may experience a variety of symptoms including pain, fullness, and squeezing sensation of the chest; jaw pain, toothache, headache, shortness of breath, nausea, vomiting, and general epigastric (upper middle abdomen) discomfort; sweating, heartburn, and indigestion; arm pain (more commonly the left arm but may be the either arm), upper back pain, general malaise (vague feeling of illness); no symptoms (approximately one quarter of all heart attacks are silent without chest pain or new symptoms). Silent heart attacks are especially common among patients with diabetes mellitus.

Even though the symptoms of a heart attack at times can be vague and mild, it is important to remember that heart attacks producing no symptoms or only mild symptoms can be just as serious and life-threatening as heart attacks that cause severe chest pain. Too often patients attribute heart attack symptoms to “indigestion” or “stress” and consequently delay seeking prompt medical attention. One cannot overemphasize the importance of seeking prompt medical attention in the presence of symptoms that suggest a heart attack. Early diagnosis and treatment saves lives and delays in reaching medical assistance can be fatal. A delay in treatment can lead to permanently reduced function of the heart due to more extensive damage to the heart muscle. Death may also occur as a result of a sudden onset of arrhythmia such as ventricular fibrillation.

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