Morphologic features and pathology of the aging heart

Cardiovascular diseases are the leading cause of death in industrialized nations, and increasing age is the strongest risk factor for cardiovascular disease. As we age, there are numerous functional and structural changes that occur in the cardiovascular system that contribute to increased morbidity and mortality. Cardiac structures undergo progressive fibrosis, calcification, and/or degeneration that lead to physiologic dysfunction. In the valves, these changes result in stenosis and/or regurgitation, with degenerative/calcific aortic stenosis being the most common valve disease in older adults. Myocardial fibrosis may lead to systolic/diastolic dysfunction and arrhythmias, while fibrosis of the conduction system is associated with conduction disorders and arrhythmias. Major arteries become “stiffer” with age, especially when other conditions common in older individuals, such as hypertension or diabetes, are present. Age is a potent risk factor for coronary atherosclerosis in men and women, and coronary artery disease accounts for a large proportion of cardiovascular deaths in older adults. Cardiac amyloidosis is more common in older individuals and is an increasingly recognized cause of heart failure. This chapter summarizes morphologic changes in the aging heart and their impact on cardiovascular disease in the older population.