Heart disease and stroke are closely tied for many reasons. People who have one heart or vascular condition (high blood pressure, high cholesterol, heart disease, diabetes, peripheral artery disease) are at increased risk for developing other related conditions. Heart and vascular diseases that increase stroke risk include:
Prior Stroke. A history of a prior stroke or TIA significantly increases the risk for a subsequent stroke. People who have had at least one TIA are 10 times more likely to have a stroke than those who have not had a TIA.
Prior Heart Attack. People who have had a heart attack are at increased risk of stroke.
High Blood Pressure. High blood pressure (hypertension) of contributes to about 70% of all strokes. People with hypertension have up to 10 times the normal risk of stroke, depending on the severity of the blood pressure in the presence of other risk factors. Hypertension is also an important cause of so-called silent cerebral infarcts, or blockages, in the blood vessels in the brain (mini-strokes) that may predict major stroke. Controlling blood pressure is extremely important for stroke prevention.
Unhealthy Cholesterol Levels. A high total cholesterol level increases the risk of developing atherosclerosis (hardening of the arteries) and heart disease. In atherosclerosis, fatty deposits (plaques) of cholesterol build up in the arteries of the heart.
Heart Disease. Coronary artery disease (heart disease), which is the end result of atherosclerosis, increases stroke risk. Anti-clotting medications, which are used in heart disease treatment to break up blood clots, can increase the risk of hemorrhagic stroke.
Atrial Fibrillation. Atrial fibrillation, a major risk factor for stroke, is a heart rhythm disorder in which the atria (the upper chambers in the heart) beat very quickly and nonrhythmically. The blood pools instead of being pumped out, increasing the risk for formation of blood clots that break loose and travel toward the brain. Between 2 – 4% of patients with atrial fibrillation without any history of TIA or stroke will have an ischemic stroke over the course of a year. The risk is generally highest for those older than age 75, with heart failure or enlarged heart, coronary artery disease, history of clots, diabetes, or heart valve abnormalities.
Structural Heart Problems. Dilated cardiomyopathy (enlarged heart), heart valve disorders, and congenital heart defects such as patent foramen ovalae (opening in chambers of heart) and atrial septal aneurysm (bulging of heart chamber) are risk factors for stroke.
Carotid Artery Disease and Peripheral Artery Disease. Carotid artery disease is a serious risk factor for stroke. Atherosclerosis can cause fatty build-up in the carotid arteries of the neck, which can lead to blood clots that block blood flow and oxygen to the brain. People with peripheral artery disease, which occurs when atherosclerosis narrows blood vessels in the legs and arms, are at increased risk of carotid artery disease and subsequently stroke.