briefly describe various abnormalities in the functioning of human heart

Solution:

Some of the common heart diseases are myocarditis, myocardial infarction (heart attack), stenosis, stroke, acrdiac arrest, atherosclerosis etc.  

Atherosclerosis is the thickening of arterial wall due to deposition of cholesterol, triglycerides and other fatty material in the arteries. Due to this arteries become constricted for blood flow leading to severe coronary heart disease. 

During stroke, heart valves may not be able to regulate flow of blood between chambers of heart or between heart and arteries. Dysfunctional heart valves cause heart to work harder that weakens the heart muscles. This in turn affects the flow of blood to brain and results in stroke.  

During a heart attack, blood flow to the heart is blocked, often by a blood clot or a buildup of plaque in the arteries.Symptoms may start slowly and persist for hours, days, or weeks before the heart attack. The heart continues to beat, but because of the blockage, it is not receiving all the oxygen-rich blood it requires.

In cardiac arrest, the heart stops beating and needs to be restarted. While a heart attack is a circulation problem, cardiac arrest is an electrical problem triggered by a disruption of the heart's rhythm.