Cardiovascular aging and cardiovascular diseases in elderly patients

Abstract

Elderly population is increasing year by year as a result of the improvements in civilization, medicine and living conditions. This fact leads to huge increases in certain clinical conditions such as coronary artery disease, heart failure, hypertension, and diabetes among elderly people. For this result, understanding age-associated changes in healthy people is a necessity. Aging causes arterial stiffening with decreased elasticity and compliance of the aorta and great arteries leading to higher systolic arterial pressures and increased resistance to left ventricular ejection. Subsequent mild left ventricular hypertrophy and interstitial fibrosis leading to a decrease in myocardial relaxation follows this fact increasing the importance of atrial contraction in diastolic filling of left ventricle. With aging, connective tissue increases in all parts of the heart including the conduction system which may lead to a partial or complete separation of the sinus node from the atrial musculature causing to the loss of sinoatrial pacemaker cells up to 50 - 75 % resulting in a decrease of sinus rate with altered autonomic modulation. Calcification of the aortic and mitral annuli, with central fibrous body and upper part of the interventricular septum occurs with aging affecting the neighboring parts of conduction system as atrioventricular node, AV bundle and proximal bundle branches. Aging decreases the sensitivity of the heart to adrenergic stimulation and diminishes chemoreceptor and baroreceptor reactivity. Although myocardial contractility does not change primarily with aging, but age associated diseases like hypertension and coronary artery disease may lead to the deterioration of ventricular performance. On the other hand, age related decreases in heart rate and left ventricular filling causes a reduction in cardiac output. A decrease in maximum capacity for physical work with aging is due to both diminished cardiac and peripheral factors. Physical conditioning might improve or at least delay some of the age related cardiovascular deficits. Due to all of these age associated cardiovascular changes, elderly people are more likely to develop cardiovascular disease or the preexisting cardiovascular diseases may worsen rapidly in the elderly.