Ageing and heart disease
LAST week we started looking at ageing and heart disease, exploring insomnia and heart disease, sleep apnoea and heart disease and whether we are getting enough and quality sleep. This week we will continue by examining heart diseases commonly associated with an ageing heart.
1) Heart failure
Heart failure increases in frequency as age increases, particularly from heart disease associated with normal pumping function. The underlying changes that lead to heart failure can simply be increased thickness of the walls and decreased compliance which leads to either the heart being unable to fill with blood or only being able to fill at high pressures. An easy way to appreciate the problem is to think of a normal heart as a party balloon and how easy it is to inflate with the breath. You can then think of a severely diseased thick/stiff heart as a car tire with which you would have great difficulty inflating without using a pump. An important cause of heart failure that is increasingly being recognised, particularly in black populations is amyloid heart disease where protein is deposited in the muscle of the heart. This diagnosis requires a high degree of suspicion and can be difficult to treat although new drugs are currently being developed. Patients often present with shortness of breath, inability to exercise and swelling of the legs. Cardiac amyloid is now recognised to be frequently associated with a particular gene that is found most in black individuals. It is now known to account for a significant percentage of heart diseases in countries with significant black populations including Jamaica. In recognition of this, the Heart Institute of the Caribbean (HIC) has partnered with the Ivy League Yale University in the USA to launch a ground-breaking investigation of this ailment in Jamaica with the hope of enhancing early diagnosis and effective treatment among Jamaican heart failure patients. This investigation will be carried out by the heart failure specialists at HIC and Yale University. We encourage patients with heart failure to enrol with the heart failure clinic at HIC to benefit from these opportunities.
2) Abnormalities of heart rhythm
Ageing can be associated with the occurrence of both slow and rapid heart rates. Slow heart rates can be the result of loss or damage to the conduction system. Problems can occur at the pacemaker area which determines the heart rate or the “wires” which serve to conduct the electrical current. The underlying issues may include death of cells or cell damage from a variety of different processes. Patients can present with passing out or the inability to exert themselves. In such situations, a pacemaker will often be curative. Fast heart rhythms are also commonly seen of which the most common is atrial fibrillation. Atrial fibrillation occurs because of changes in the structure of the atrial wall (upper chamber of the heart) which make it prone to chaotic electrical activity. These changes can include loss of muscle tissue, increase in fibrous (scar) tissue, atrial enlargement, and protein deposition. Patients often complain of palpitations, but long-standing untreated atrial fibrillation may lead to heart failure or stroke.
3) Coronary artery disease
The prevalence of coronary artery disease increases with age. Most of this increase is related to the fact that risk factors for coronary disease are more common as we age as opposed to a direct impact of age on the coronary arteries. Nonetheless age is one of the most important risk factors for coronary disease.
4) Valvular heart disease
Narrowing of the aortic valve from fibrosis and calcification is the most common significant age-related valvular heart disease. When this is severe, patients will usually complain of chest pain, difficulty breathing and passing out. As this problem increases in severity, patients will develop recurrent angina (chest pain) from inability to generate enough cardiac output through the blocked valve to supply nutrients and oxygen to the heart muscle. Other significant problems with severe aortic valve stenosis include heart failure and sudden death. This can be treated by replacement of the aortic valve by either surgery or stenting. Less commonly calcification around the mitral valve can cause either narrowing or leaking of the valve which may require valve replacement.
Reducing the risk of age-related heart disease
This is currently an area of active research. It remains unclear what separates patients who have changes in cardiac structure that are mild and patients who have severe changes that result in disease with significant symptoms. It is currently thought that efforts should be made to identify factors that may worsen the normal age-related changes. For example, hypertension that is untreated leads to increased wall thickness, decreased heart compliance, and increases the risk of heart failure and atrial fibrillation. There are some hints that a healthy lifestyle may be of help including dietary changes (Mediterranean/DASH diet), regular exercise, stress reduction and smoking avoidance. Lifestyle changes likely have their greatest impact in reducing the incidence of coronary artery disease in the elderly. Unfortunately, outside of coronary artery disease, hard evidence that we can prevent many age-related cardiac conditions is quite limited. Many of these conditions, however, can be treated if recognised, so if symptoms consistent with cardiac disease are noted in the elderly, consultation with your physician or a heart doctor is strongly advised.
Dr Ernest Madu, MD, FACC and Dr Paul Edwards, MD, FACC are consultant cardiologists for Heart Institute of the Caribbean (HIC) and HIC Heart Hospital. HIC is the regional centre of excellence for cardiovascular care in the English-speaking Caribbean and has pioneered a transformation in the way cardiovascular care is delivered in the region. HIC Heart Hospital is registered by the Ministry of Health and Wellness and is the only heart hospital in Jamaica. Correspondence to info@caribbeanheart.com or call 876-906-2107.