The heart is responsible for pumping blood to the rest parts of the body. The efficient heart function helps to provide oxygen and nutrients to the various parts of the body to enable them carry out their unique functions. When there is a disruption in the contractile ability of the heart, the heart tries to cope by developing mechanisms that would help remedy the disruption in muscle contractility. A failure in these mechanisms leads to reduced cardiac output and subsequently to heart failure.
Definition: Heart failure (circulatory failure) is the inability of the heart to pump sufficient blood, oxygen and nutrients to the various parts of the body to meet up their metabolic needs.
Heart failure is not a disease condition; it is a syndrome which results from other pathophysiological conditions taking place in other parts which place increased demand on the heart. Heart failure can be acute or chronic.
TYPES: There are two types of heart failure – Left ventricular failure and right sided failure (congestive cardiac failure).
1. Left ventricular failure: Left ventricular failure results from the inability of the left ventricle to pump sufficient blood from the left side of the heart into the aorta from where it is distributed to the rest parts of the body.
Causes of Left ventricular failure
i. Myocardial infarction (coronary artery occlusion)
ii. Valvular defects
iii. Pregnancy (when there is an underlying disease)
v. Rheumatic fever
x. Syphilitic heart disease
xii. Prolonged dietary deficiency e.g. beri beri
xiii. Pulmonary heart disease due to disorders of the lungs e.g. chronic obstructive pulmonary disease (COPD)
xiv. Paget’s disease
xvi. Transfusion or infusion overloading
xvii. Emotional stress.
Signs and symptoms of LHF
ii. Dyspnoea (difficult breathing) on exertion
v. Mental confusion
vi. Paroxysmal nocturnal dyspnoea (cardiac asthma)
vii. Anorexia (loss of appetite for food)
viii. Decreased tolerance to exercise
ix. Pulmonary rales
x. Reduced urinary output (oliguria)
xi. Rapid irregular pulse