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2022年4月19日 · Thrombocytopenia is when you don't have enough platelets, cells in your blood that stick together to help it clot. Sometimes, the condition doesn’t cause any problems at all. But if you have...
- Pathophysiology
- Significance
- Signs and symptoms
- Overview
- Prognosis
A blood pressure reading appears as two numbers. The first and higher of the two is a measure of systolic pressure, or the pressure in the arteries when the heart beats and fills them with blood. The second number measures diastolic pressure, or the pressure in the arteries when the heart rests between beats.
Optimal blood pressure is less than 120/80 (systolic/diastolic). In healthy people, low blood pressure without any symptoms is not usually a concern and does not need to be treated. But low blood pressure can be a sign of an underlying problem -- especially in the elderly -- where it may cause inadequate blood flow to the heart, brain, and other vi...
Chronic low blood pressure with no symptoms is almost never serious. But health problems can occur when blood pressure drops suddenly and the brain is deprived of an adequate blood supply. This can lead to dizziness or lightheadedness. Sudden drops in blood pressure most commonly occur in someone who's rising from a lying down or sitting position t...
Postural hypotension is considered a failure of the cardiovascular system or nervous system to react appropriately to sudden changes. Normally, when you stand up, some blood pools in your lower extremities. Uncorrected, this would cause your blood pressure to fall. But your body normally compensates by sending messages to your heart to beat faster ...
The risk of both low and high blood pressure normally increases with age due in part to normal changes during aging. In addition, blood flow to the heart muscle and the brain declines with age, often as a result of plaque buildup in blood vessels. An estimated 10% to 20% of people over age 65 have postural hypotension.
2023年11月15日 · What Is Atrial Fibrillation? Atrial fibrillation, also called AF or AFib, is a quivery, fluttery heartbeat. You might also hear the doctor call it arrhythmia. It means your heart’s normal...
2023年12月18日 · What Is a Troponin Test Used For? How Does a Troponin Test Work? 13 min read. The cardiac troponin test detects damage to the heart muscle. Troponin is a protein that appears in the blood only when...
2022年8月20日 · What Is High Cholesterol? There are two major forms of cholesterol: Low-density lipoprotein or LDL, also known as "bad" cholesterol, and high-density lipoprotein or HDL, also called "good"...
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2022年3月23日 · LDL is a tiny blob made up of an outer rim of lipoprotein with a cholesterol center. Its full name is "low-density lipoprotein." LDL vs. HDL. Most of the cholesterol in your body is LDL. The...
