New Delhi, June 5 -- As temperatures soar across India during summer, heart patients often get hit with bigger problems from heat-related illnesses. When it gets extremely hot, the whole cardiovascular system works overtime: blood vessels dilate to help dissipate heat through the skin, while the heart has to pump faster and harder to maintain circulation. At the same time, dehydration starts thickening the blood, so everything feels more strained than usual, and that is not a small matter. People with coronary artery disease, heart failure, hypertension, or those who have had a heart attack before can see this extra load turning into dangerous complications such as arrhythmias, worsening heart failure, or even sudden cardiac events.

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