Diffuse bilateral thyroid lesions do not usually cause hypertrophic cardiomyopathy. Hypertrophic cardiomyopathy is a hereditary disease that is not associated with thyroid lesions. However, bilateral diffuse thyroid lesions that are accompanied by hyperthyroidism (hyperthyroidism) can lead to hyperthyroid heart disease (hyperthyroid heart). Bilateral diffuse thyroid lesions may be diffuse toxic goiter or simple goiter. In the former case, it often causes hyperthyroidism, and increased secretion of thyroid hormone in hyperthyroidism patients can further cause myocardial damage, leading to arrhythmias, cardiac enlargement, cardiac hypoplasia and other manifestations, which is known as hyperthyroidism heart, which is one of the serious complications of hyperthyroidism. If bilateral diffuse thyroid lesions occur and hypertrophic cardiomyopathy is present at the same time, it is important to consult a medical professional for diagnosis and treatment because hyperthyroidism may aggravate heart disease.