A moderate degree of hypertension for more than five years causes severe damage to vital organs. Complications include:
1. Hypertrophy or enlargement of the heart
2. Heart failure that causes fluid to accumulate in the lungs and the legs manifested by severe shortness of breath
3. Myocardial infarction
4. Atrial fibrillation, a serious arrhythmia which causes palpitations, leads to stroke, and requires a bothersome commitment to anticoagulation with blood thinners
5. Stroke that may be thrombotic or hemorrhagic
6. Damage to the kidney that leads to renal dysfunction and renal failure
7. Aortic aneurysm prone to rupture
See the chapter Hypertension for causes of hypertension and drug and nondrug treatment.