How Does Hypothyroidism Affect the Heart?
Mar 19, 2025
Source: Cainiu Health
Dr. Tian Hongbo
Introduction
Hypothyroidism can affect multiple aspects of cardiac function, including slowed heart rate, reduced myocardial contractility, hypertension, hypercholesterolemia, and pericardial effusion. When hypothyroidism occurs, declining thyroid hormone levels lead to slowed cardiac electrophysiological activity and reduced heart rate. This may result in bradycardia, with patients often experiencing a slow heartbeat and fatigue.
Hypothyroidism can affect multiple aspects of cardiac function, including bradycardia, weakened myocardial contractility, hypertension, hypercholesterolemia, pericardial effusion, and others. If concerned, timely medical consultation is recommended. Specific analyses are as follows:
1. Bradycardia: In hypothyroidism, decreased thyroid hormone levels slow down the heart's electrophysiological activity, resulting in reduced heart rate. This may cause bradycardia, with patients often experiencing slow heartbeat and fatigue.
2. Weakened myocardial contractility: Thyroid hormones are important for normal myocardial contraction. In hypothyroidism, weakened myocardial contractility leads to decreased cardiac pumping capacity, potentially reducing cardiac output and affecting systemic circulation.
3. Hypertension: Hypothyroidism may increase peripheral vascular resistance, leading to elevated blood pressure. Long-term hypertension increases the risk of cardiovascular diseases, such as coronary artery disease and stroke.
4. Hypercholesterolemia: Hypothyroidism causes lipid metabolism abnormalities, increasing blood levels of low-density lipoprotein cholesterol, thereby raising the risk of atherosclerosis and affecting heart health.
5. Pericardial effusion: Hypothyroidism may lead to pericardial inflammation and fluid accumulation, forming pericardial effusion. Large pericardial effusions may compress the heart, impairing normal cardiac diastolic and systolic functions, and severe cases may result in cardiac tamponade.
In daily life, maintaining a healthy lifestyle, improving dietary habits, engaging in appropriate physical exercise, enhancing physical fitness, and reducing disease susceptibility are recommended.
[References]
[1] Gu Liang, Lin Huimin. Effects of hypothyroidism in late pregnancy on maternal glucose and lipid metabolism, cardiac function, and pregnancy outcomes [J]. Chinese Journal of Family Planning, 2021, 29(11): 2436-2440.
[2] Gao Xia, Kong Lingyun, Chen Lingling, et al. Impact of hypothyroidism on left and right ventricular deformation capacity and synchronicity [J]. Chinese Circulation Journal, 2019, 34(09): 893-898.
