Via an abnormality of cardiac function (detectable or not), a heart may fail to pump blood at a rate commensurate with the requirements of the metabolising tissues or can do so only with an elevated diastolic filling pressure. We call it heart failure.
Generally, the mortality rate following hospitalisation for patients with heart failure is 10.4% at 30 days, 22% at one year, and 42.3% at five years, despite marked improvement in medical and device therapy.
Ischaemic heart disease is the most common cause of heart failure in the industrialised world. In the developing world, valvular heart disease takes its toll. However, the developing nations are rapidly becoming urbanised and affluent; people are eating a more processed diet. They are leading a more sedentary lifestyle. It has resulted in its increased rate, together with increased rates of diabetes and hypertension.
The clinical presentation of heart failure can worsen due to conditions that increase myocardial oxygen consumption and demand beyond a critical level – high-output states. These include profound anaemia, thyrotoxicosis, myxoedema, Paget disease of bone. Albright syndrome (fibrous dysplasia), multiple myeloma, glomerulonephritis, Cor pulmonale. Polycythaemia vera, obesity, carcinoid syndrome, pregnancy. And nutritional deficiencies like thiamine deficiency and Beriberi.
Many patients with heart failure achieve a ‘stable’ state in which they can safely accomplish activities of daily living – compensated state. However, some patients with compensated heart failure can decompensate. It is commonly due to; inappropriate reduction in treatments like the restriction of dietary sodium, reduction in the level of physical activity or drug regimen. Uncontrolled hypertension and cardiac arrhythmias like atrial fibrillation are two other common causes of decompensated heart failure.
Several conditions can cause heart failure if their management is not prompt. These include coronary artery disease, diabetes, hypertension, valvular heart disease. Arrhythmias, infections, and inflammation like myocarditis. Peripartum cardiomyopathy, congenital heart disease, drugs like alcohol and cocaine, doxorubicin. Hypertrophic cardiomyopathy, restrictive cardiomyopathy like amyloidosis, sarcoidosis, and constrictive pericarditis.
Acute mitral or aortic regurgitation, myocardial infarction, myocarditis, and sepsis commonly cause acute heart failure. Drugs like cocaine, calcium channel blockers, and beta-blockers also cause the condition.
A few salient signs are particularly notable of the condition.
- Kussmaul sign is when the jugular venous pressure increases with respiration in heart failure or constrictive pericarditis due to an increase in right atrial pressure and hence right-sided heart failure.
- Elevated jugular venous pressure is the most reliable indicator of fluid volume overload in older patients.
- An S3 gallop is the earliest cardiac physical finding in decompensated heart failure. It occurs in the absence of severe mitral or tricuspid regurgitation or left-to-right shunts.
- Features of advanced disease in elderly patients include; confusion, memory impairment, anxiety, headaches, insomnia, bad dreams or nightmares, and rarely, psychosis with disorientation, delirium, or hallucinations.
- Nocturia is an early sign in the elderly: oliguria is a late sign. Nocturia develops following a reduction of the deficit in cardiac output to oxygen demand during recumbency. It leads to diminished renal vasoconstriction, which culminates in the increased formation of urine.
In a nutshell, heart failure remains one of the leading causes of mortality globally, that every one of us has a role to play in optimising therapy in the wake of a failing heart. This article should act as a wake-up call for you to go and read more about the condition and understand it. Myocardial infarction remains a threat around the world especially, in societies with frail health care systems. Whether you agree or not, suffering a heart attack in Uganda is equivalent to a death sentence.