Cardiac Risk Factor: Hypertension

Hypertension is mostly an asymptomatic disease with insidious onset and progression producing permanent damage to the cardiovascular system. About 50% of the hypertensives are not treated at all.

We have made significant strides in improving the detection and management of high blood pressure, thereby reducing its complications and mortality. However, the incidence of high blood pressure remains unaltered for the past several decades. We have about 50 million Americans with high blood pressure. Hypertension is more prevalent among African-Americans and increases with age.

Hypertension is mostly an asymptomatic disease with insidious onset and progression, producing permanent damage to the cardiovascular system. Symptoms of headache or shortness of breath are late manifestations. Once high blood pressure is clinically detected, some damage has certainly occurred to the cardiovascular system. The left ventricle, the main pumping chamber of the heart, responds to long-standing hypertension by thickening and enlargement (left ventricular hypertrophy). Two types of changes occur in the arteries of a hypertensive patient. The thickening of the endothelium and the intima with the development of plaque is fundamentally the process of atherosclerosis. ATHEROSCLEROSIS eventually invades the intima producing sclerosis and calcification. Independent of atherosclerosis, the arteries undergo a process of ARTERIOSCLEROSIS with advancing age. Here, the arteries progressively lose their compliance (elasticity) and become stiff. The changes occur in the adventitia and media of the vessels where the elastic fibers are replaced by fibrous tissue and calcium. In high-risk patients, both atherosclerosis and arteriosclerosis co-exist making matters worse. However, meticulous reduction of high blood pressure certainly reduces the cardiovascular events such as myocardial infarction, stroke and congestive heart failure.

At times it is difficult to convince the patient to accept pharmacological treatment for hypertension, particularly when the medications have some side effects, and the patient is relatively free of symptoms. The compliance to medications and maintain treatment is generally poor. That is the reason why about 50% of our hypertensives are not treated at all; about 25% are treated, but not properly controlled; and only the remaining 25% are properly managed. Salt restriction, weight reduction, exercise, and relaxation techniques have a significant impact on the management of hypertension. Above all, the awareness of this deadly disease, with its late manifestations such as stroke, heart attack, congestive heart failure, renal failure, and peripheral vascular disease must be made known to the patient at a very early stage.

Here, I shall emphasize that all hypertensives must not be viewed or treated the same way. The 6th Report of the Joint National Committee on Detection, Evaluation, and Treatment of Hypertension has made the strongest recommendation that in patients with diabetes, coronary artery disease, and renal failure any blood pressure above 130/85 mmHg must be treated. Moreover, if a patient has renal failure with proteinuria (more than 1 gram in 24 hours) the blood pressure must be kept below 125/75 mmHg.

There is a misconception among patients, as well as some physicians, that diastolic hypertension is more important than systolic hypertension. The fact is that in a truly hypertensive patient, both systolic and diastolic pressures gradually rise in a parallel fashion until the patient is 50-55 years old. At this stage, the peripheral arteries become thick and non-elastic (non-compliant). From then on, the systolic pressure could still rise while the diastolic pressure gradually falls. The fall in diastolic pressure is a function of the lack of compliance of the peripheral arteries.