Body processes

Vascular Resistance – Function, Task & Diseases

Vascular Resistance

The vascular resistance is defined by the physical resistance of a capillary , vein or artery that opposes the flowing blood . Vascular diseases can affect the entire organism but also an individual organ such as the heart or the brain . In any case, the first warning signals must be heeded in order to be able to counteract a serious course of the disease, which can also be fatal.

What is vascular resistance?

In the individual vascular sections, the vascular resistance is not identical, but rather different. Dynamic control is provided by the circulatory system.

If the definition of resistance refers to a single organ, a distinction is made between coronary , pulmonary and cerebral vascular resistance .

function & task

The coronary vascular resistance consists of a vascular and an extravascular component. The vasale provides most of the physical regulation of coronary perfusion . The extravascular is based on mechanical stress exerted by myocardial contraction and relaxation. 

Pulmonary vascular resistance (PVR) refers to the resistance in the pulmonary circulation . This begins in the pulmonary artery and extends into the atrium of the left heart. It cannot be measured clinically, which is why the pulmonary capillary closure pressure is used as an approximation to determine the pulmonary resistance. Experts also speak of wedge pressure (PAP). In addition, pulmonary vascular resistance is divided into acute pulmonary hypertension and chronic pulmonary hypertension.

Cerebral vascular resistance is the resistance to blood flow that the cerebral vessels offer to blood flow and is driven by systemic blood pressure. In this way, blood flow to the brain is regulated.

Diseases & Ailments

Significant diseases associated with vascular resistance include: 

Coronary heart disease (CHD): It is caused by insufficient blood flow to the heart muscle , which means that the oxygen and nutrient requirements are not met. The cause is often arteriosclerosis in the coronary arteries . Coronary heart disease includes angina pectoris , myocardial infarction and sudden cardiac death . Plaques are to blame. These are fatty deposits that completely or partially block blood flow.

The pulmonary vascular diseases:

The speech is usually from the pulmonary embolism ( pulmonary embolism ). Obstruction of a pulmonary artery by blood clots is responsible for this disease. Usually a leg vein thrombosis precedes it.

Primary pulmonary hypertension:

Its incidence is around 1,1,000,000, which is why this clinical picture is one of the very rare ones. The exact cause is also not yet known.

Secondary pulmonary hypertension:

It usually occurs as a result of another underlying disease. In order to protect the lungs , this underlying disease must therefore be treated as a priority. This is the only way to control and regulate pulmonary hypertension.

Acute pulmonary hypertension:

Here, the pulmonary vessels are affected by narrowing. In the early stages, this often only exists temporarily. For example under load. The radius of the vessels decreases due to the contraction of the vascular muscles, which leads to an increase in blood pressure .

Chronic pulmonary hypertension:

In this case, a remodeling of the pulmonary vessels can be diagnosed. The vascular musculature increases in size before slowly converting into connective tissue . The pulmonary vessels are then less flexible and cannot regain their flexibility.

If sclerosis is added, the condition of those affected deteriorates rapidly. The lungs are no longer properly ventilated, which means that an increasing lack of oxygen in the lungs becomes noticeable over time. Another consequence of this clinical picture is the continuous reduction in cardiac output .

Cerebral vascular diseases: The apoplexy ( stroke ) as a sudden event ranks among the 3 most common causes of death. The cause is 40-50% thrombosis , 30-35% embolism and 20-25% cerebral hemorrhage , triggered by blood leaking from a cerebral artery. High blood pressure and a reduced ability of the blood to clot are beneficial . This also applies to intracerebral venous congestion. For example, a sinus vein thrombosis .

Vascular diseases of the brain and spinal cord : Aneurysms often occur in the brain and spinal cord . This is the result of pathological changes in the arteries (arterial walls). These are located on the surface of the brain or spinal cord. The size of an aneurysm can range from a few millimeters to 50 millimeters in diameter. The triggers include not only arteriosclerotic changes in the aneurysm wall. Disturbed blood flow or blood pressure are also possible. Genetic or inflammatory vascular injuries or vascular changes can also be the cause.

Symptoms include an extremely severe headache , which may be accompanied by nausea and vomiting . The following symptoms can be observed in pulmonary hypertension: Most of those affected experience dyspnea (breathlessness, shortness of breath ). A worse general condition, circulatory disorders up to syncope ( circulatory collapse ) and angina pectoris (chest tightness) occur in almost every second patient. Symptoms such as tiredness and the formation of edema ( swelling ) are also frequently observed. A cyanosis(blue-violet coloring of fingertips, lips or skin) and Raynaud’s syndrome (temporary circulatory disorders) occur less frequently.

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.