Cardiomyopathy refers to the abnormality of the heart muscles while hypertrophic describes the abnormal thickening of the cardiac muscles. The exact cause of hypertrophic cardiomyopathy is not identified but there are primary and secondary causes that onset the disease. The primary cause of HCM can be genetics as in certain breeds and young males, the condition is more prevalent e.g., Maine Coon, Chartreux, and Persian cats. Hypertension and hyperthyroidism are the secondary causes of the disease which are most common in older cats. In the initial stage of HCM, the cat may not show any obvious symptoms of being ill but with the progression of the disease, they may show symptoms like labored breathing, lethargy, loss of appetite, and certain behavioral changes. In most cases, the disease goes unnoticed or the diagnosis is done after the sudden death. The diagnosis includes a physical examination to detect abnormal rhythm, radiographs, and cardiac ultrasound. If the condition is left untreated, it leads to heart failure. The thickened walls of the heart do not pump the blood efficiently and blood becomes stagnant in the heart chambers and forms clots. These blood clots are also pumped with the blood and cause thromboembolism. They can reside in any artery especially in the leg and cause severe pain and paralysis. There’s no known cure for the condition and the treatment includes managing the signs like controlling the heart rate and treating the secondary diseases.