The ageing heart

Ageing decline

As we age the heart valves can become calcified. The left ventricular mass, systolic (contracting) and diastolic (relaxed) function tend to decrease slowly. The ejection fraction (the % of blood ejected by a contaction) is usually well-preserved. The electrical circuits degrade. With age, some patients will gradually develop atrial fibrillation or heart failure. In some people, the valves become too narrow (stenosis) and blood flow is restricted. In some people, the valves stop sealing properly and blood is able to leak backwards through the valve (regurgitation / valvular insufficiency). These problems can remain undetected if the person never develops symptoms.

Chronic cardiac diseases

Valvular diseases: This is particularly common with certain risk factors such as auto-immune diseases, rheumatic fever, or congenital abnormalities such as bicupid aortic valve (healthy people have 3 flaps in the aortic valve, but these patients are born with only 2).

Cardiac arrhythmias: Some patients develop heart block, where signals from the top of the heart cannot reach the bottom efficiently or cannot reach the bottom at all. Some patients develop uncoordinated twitching of the top two chambers of the heart (atrial fibrillation), or uncoordinated twitching of the bottom two chambers of the heart (ventricular fibrillation). Ventricular fibrillation is usually fatal if untreated.

Cardiomyopathy: More rarely, the heart muscle itself can become diseased. In some cases the heart muscle loses its contractile power and the heart dilates (dilated cardiomypathy).

Cardiovascular disease: In many patients the blood supply to the heart is restricted, causing pain on exertion (stable angina) or unpredictable pain (unstable angina). If the blood supply is completely blocked the heart muscle dies (myocardial infarction / MI / heart attack). After an infarction the heart often loses some of its contractile power, the electrical or structural components may become diseased, and holes can appear in the heart where the muscle death has penetrated through each layer of tissue.

Chronic lung disease: thanks to smoking, there is a large population of patients with chronic obstructive pulmonary disorder (COPD). This disease deserves an article of its own but one of the consequences is reduced ventilation of the lungs. Since the alveoli (the air sacks) are not being properly ventilated, the tiny blood vessels around them will try to divert blood away so that it can perfuse healthy alveoli. The body does this because it does not "know" that the patient has no well-ventilated alveoli. Since the blood is being diverted away from every alveolus, the heart has to pump very hard to force blood through these resisting vessels. With time, this causes the heart to become dysfunctional and right-sided heart failure known as cor pulmonale (latin: heart of the lungs) develops.

Impact on care

Cardiac arrhythmias and cardiovascular disease are relatively well controlled these days. Unfortunately cardiomyopathy is still difficult to treat, and post-MI damage is still impossible to reverse. Some patients must face transplantation or death. 

Patients with heart failure often struggle with fluid retention in their tissues. With chronic progressive heart failure, this fluid retention will inevitably cause fluid to accumulate in the air spaces of the lungs (pulmonary oedema). These patients experience gradually worsening breathlessness until they die.