Stroke and heart disease

How are stroke and heart disease related?

Stroke is often due to sudden loss of blood supply to a region of the brain which usually results in paralysis of a part of the body. Stroke could also be due to bleeding into a part of the brain. Strokes and heart disease are linked together in various ways. In general, risk factors for stroke and some forms of heart disease are similar. Strokes due to blocks in blood vessels, can be seen along with blocks in blood vessels of the heart. Stroke can occur after a heart attack as well. Heart attack damages a part of the heart muscle. This can lead to damage of the inner lining of the heart in that region. A blood clot can form on the inner surface of the heart as a consequence. These clots can break away into the circulation and get lodged into a blood vessel of the brain. The clot thus blocks a blood vessel of the brain and causes stroke.

Another type of heart disease which leads to stroke is an abnormal rhythm of the heart known as atrial fibrillation. In atrial fibrillation, there is a fast irregular rhythm originating in the upper chambers of the heart. The rhythm is so fast that effective contractions of the upper chambers cease. This leads to stagnation of blood in certain parts of the left atrium (upper chamber of the heart), where a blood clot can form. These clots can also get dislodged and travel to blood vessels of the brain. They in turn block a blood vessel of the brain and cause stroke.

Another reason for stroke is high blood pressure. When the blood pressure goes very high suddenly, small blood vessels in the brain may break leading to a bleed into the brain matter. This form of stroke (hemorrhagic stroke) is generally more dangerous than a stroke due to blockage of a blood vessel. Even without a bleed, brain function can be altered due to high blood pressure, causing alteration in the level of consciousness. But then that is not a stroke, but called as hypertensive encephalopathy (brain disease due to high blood pressure).

Symptoms of heart disease

What are the important symptoms of heart disease?

Symptoms depend on the type of heart disease. Sometimes there could even be silent heart disease without any symptoms. Many of the birth defects of the heart remain asymptomatic for long periods. Some become symptomatic during another illness or a major stressful event. Occasionally the very first manifestation of a silent underlying heart disease is sudden death. Apart from these two extremes, most significant heart diseases have some symptom or other though there may be a lot of variation between individuals. The severity of symptoms may not correlate with the severity of heart disease in some cases.

Important symptom of heart disease which every one is familiar with is the severe chest pain of a heart attack. As the name implies, it often occurs out of the blue and is quite disabling. A crushing feeling may be felt instead of chest pain, and it may spread to the arms or jaw. It may be associated with profuse sweating or sometimes breathlessness and dizziness. Some even feel an impending doom.

Classical symptom of reduced blood supply to the heart is chest pain brought on by exertion and relieved by rest (effort angina). This indicates gradually increasing blockage of coronary arteries which supply oxygenated blood to the heart. This pain may also spread to the jaw, neck or the arms. Occasionally pain may be felt in the upper part of the stomach. Rarely jaw pain or pain in the wrist occurs without chest pain.

Breathlessness brought on by exertion and relieved by rest is another important symptom of heart disease, though it can be due to lung disease or even reduced amount of hemoglobin in the blood (anemia). Sudden breathlessness during sleep and breathlessness which gets worse on lying down are also important symptoms of some forms of heart disease.

Palpitation or undue awareness of one’s heart beats is another important symptom of heart disease, though it may occur with anxiety and undue exertion as well. Palpitation can be fast, slow, regular or irregular, depending on the abnormality in the heart rhythm.

Some forms of heart disease, especially birth defects of the heart, produce a bluish discoloration of the skin and lips (cyanosis). This is due to reduced content of oxygen in circulating blood. Spitting out blood can also be a symptom of heart disease, though it is more often a symptom of lung disease.

Prolonged fever can occur with infections of the heart valve. Joint pain and swelling can occur in infections of the heart valves as well as in rheumatic fever, which can affect the heart valves.

Stroke or sudden weakness of one part of the body can be an indirect symptom of heart disease. Atrial fibrillation, an abnormal rhythm of the upper chambers of the heart, can cause clots to form in the heart. These clots can move out of the heart and block a blood vessel in the brain causing stroke. Similar clots can form in diseases of heart valves, where there is obstruction to blood flow.

High blood pressure

What is high blood pressure?

Normal pressure in the main blood vessels arising from the heart is below 120/80 mm Hg. The higher value occurs when the heart contracts and pumps blood and is known as systolic blood pressure. The lower value occurs when the heart relaxes. When the blood pressure is above 140/90 mm Hg, it is usually called high blood pressure (hypertension). Blood pressure varies with age – it is low in a new born baby and rises as the age increases. The values mentioned above are for adults above the age of 18 years. In younger individuals, we have to check with normal blood pressure chart for each age as it is difficult to memorize the values for each age.

What are the symptoms of high blood pressure?

Very often there are no symptoms for high blood pressure and a good number of individuals who have high blood pressure do not know it. High blood pressure is detected during evaluation for other illnesses. Headache, though an important symptom of high blood pressure, is most often due to other causes. Dizziness is another symptom which could occur with high blood pressure. Sometimes an individual comes with symptoms due to complications of high blood pressure rather than due high blood pressure itself.

What are the important complications of high blood pressure?

When the blood pressure goes up very high at a very fast rate, it cause rupture of a blood vessel. This typically occurs in the brain causing bleeding into the brain (cerebral hemorrhage). If a large portion of the brain is damaged due to rapid bleeding, it can lead to sudden death. Otherwise the person gets a bleeding stroke (hemorrhagic stroke), which often manifests with weakness of one side of the body with our without loss of consciousness or difficulty in speaking. High blood pressure can damage the heart, kidneys and the eyes. In the heart it can lead to heart attack and heart failure. Kidneys may fail due to high blood pressure (renal failure). Bleeding into the layers of the eye can occur due to high blood pressure. For that matter, high blood pressure can damage the blood vessels in any part of the body.

What causes high blood pressure?

The most common cause of high blood pressure in adults is unknown and it is called essential hypertension. Other causes of high blood pressure are known as secondary hypertension. Kidney disease, certain hormone disorders, obstruction to blood vessels, diseases of blood vessels and even undue anxiety and stress can cause high blood pressure. Secondary causes are more likely in younger individuals.