21/12/2025
Sudden, unexplained sweating, medically called diaphoresis, can be an important early warning sign of a myocardial infarction, commonly known as a heart attack. Unlike normal sweating caused by heat, fever, or physical exertion, this type of sweating occurs without an obvious trigger and may feel cold, clammy, or excessive. It is linked to changes in the autonomic nervous system that happen when the heart is under stress.
A heart attack usually develops as part of acute coronary syndrome. It most often occurs when an atherosclerotic plaque inside a coronary artery ruptures, leading to thrombus formation. This clot reduces or completely blocks blood flow to the myocardium. When heart muscle cells are deprived of oxygen, a condition known as ischemia, the body reacts with a strong stress response. This response activates the sympathetic nervous system and causes the release of catecholamines such as adrenaline and noradrenaline. These hormones increase heart rate, raise blood pressure, and stimulate sweat glands, resulting in sudden diaphoresis.
Diaphoresis linked to a heart attack frequently appears along with other symptoms. These may include chest pain or pressure, radiating pain to the left arm, shoulder, neck, jaw, or back, shortness of breath or dyspnea, nausea, vomiting, dizziness, and extreme fatigue. In some individuals, especially older adults, people with diabetes mellitus, and women, sweating may be one of the main symptoms, with little or no chest pain. Such cases are referred to as atypical presentations and can lead to delayed diagnosis.
The sweating occurs because the body interprets the cardiac event as a life-threatening emergency. This triggers the fight-or-flight response, stimulating sweat glands through cholinergic nerve fibers. At the same time, reduced cardiac output can cause peripheral vasoconstriction, making the skin appear pale and feel cool while sweating continues.
Recognizing sudden, unexplained sweating as a possible cardiac symptom is crucial. Early medical evaluation allows doctors to perform electrocardiography, measure cardiac biomarkers such as troponins, and begin timely treatment. Management may include antiplatelet therapy, anticoagulants, thrombolysis, or percutaneous coronary intervention. Prompt treatment limits myocardial damage, reduces complications like arrhythmias and heart failure, and improves survival.
In conclusion, sudden sweating without heat or physical effort should not be ignored. When it appears unexpectedly, especially with other cardiovascular symptoms, it may signal an early stage of a heart attack and requires immediate medical attention.
