ANGOR DE PRINZMETAL PDF

Mechanism[ edit ] The mechanism that causes such intense vasospasm, as to cause a clinically significant narrowing of the coronary arteries is so far unknown, but there are three relevant hypotheses: Enhanced contractility of coronary vascular smooth muscle due to reduced nitric oxide bioavailability caused by a defect in the endothelial nitric oxide synthetase enzyme which leads to endothelial function abnormalities. NO then diffuses out of the endothelial cells, stimulating relaxation of the nearby smooth muscle cells. In healthy arterial walls, the overall indirect relaxation induced by acetylcholine via nitric oxide is of greater effect than any contraction that is induced. When the endothelium is dysfunctional, stimulation with acetylcholine will fail to produce, or produce very little, nitric oxide.

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Mechanism[ edit ] The mechanism that causes such intense vasospasm, as to cause a clinically significant narrowing of the coronary arteries is so far unknown, but there are three relevant hypotheses: Enhanced contractility of coronary vascular smooth muscle due to reduced nitric oxide bioavailability caused by a defect in the endothelial nitric oxide synthetase enzyme which leads to endothelial function abnormalities.

NO then diffuses out of the endothelial cells, stimulating relaxation of the nearby smooth muscle cells. In healthy arterial walls, the overall indirect relaxation induced by acetylcholine via nitric oxide is of greater effect than any contraction that is induced.

When the endothelium is dysfunctional, stimulation with acetylcholine will fail to produce, or produce very little, nitric oxide. Thus, acetylcholine released by the PSNS at rest will simply cause contraction of the vascular smooth muscle.

Abnormal platelet activation e. Individuals who develop cardiac chest pain are generally treated empirically as an " acute coronary syndrome ", and are immediately tested for elevations in their blood levels of enzymes such as creatine kinase isoenzymes or troponin that are markers for cardiac damage.

They are also tested by ECG which may suggest variant angina if it shows elevations in the ST segment or an elevated ST segment plus a widening of the R wave during symptoms that are triggered by a provocative agent e.

The electrocardiogram may show depressions rather than elevations in ST segments but in all diagnosable cases clinical symptoms should be promptly relieved and ECC changes should be promptly reversed by rapidly acting sublingual or intravenous nitroglycerin. However, the gold standard for diagnosing variant angina is to visualize coronary arteries by angiography before and after injection of a provocative agent such as ergonovine , methylergonovine or acetylcholine to precipitate an attack of vasospasm.

Typically, these constrictions are fully reversed by rapidly acting nitroglycerin. Accordingly, individuals with variant angina should be intermittently evaluated for this using long-term ambulatory cardiac monitoring. Afflicted individuals should not smoke tobacco products. Smoke cessation significantly reduces the incidence of patient-reported variant angina attacks.

In addition, aspirin should be used with caution and at low doses since at high doses it inhibits the production of the naturally occurring vasodilator, prostacyclin.

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Angina de pecho

Nikomuro Prinzmwtal International Journal of Pathology. In 21 of the 23 patients studied by selective coronary arteriography. Prinzmetal angina is a clinical-electrocardiographic syndrome characterized by attacks of angina pectoris unrelated to exercise and occurring frequently after meals or during the night. Treatment of associated coronary atherosclerosis in elderly patients with PVA is advised. You may thus request that your data, should it be inaccurate, incomplete, unclear, outdated, not be used or stored, be corrected, clarified, updated or deleted. Arrhythmias are common and may be life threatening especially when the effects of vasospasm are seen in those ECG leads that reflect the potential variations of the epicardial surface of the left ventricle. The most sensitive and specific test for PVA is the administration of ergonovine intravenously.

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Comment le Angor de Prinzmetal est-il diagnostiqué?

Dit komt door een krampachtige samentrekking van het bloedvat vaatspasmen. Deze spasmen veroorzaken zuurstofgebrek in de achterliggende hartspier. Deze vorm van angina pectoris komt niet vaak voor. De arts ziet geen opvallende vernauwingen er zijn geen stolsels aanwezig Prinzmetal angina pectoris wordt ook coronair vaatspasme of variant angina genoemd. Oorzaken De oorzaak van Prinzmetal angina pectoris is onduidelijk. Om dit te ontdekken is meer onderzoek nodig. Symptomen Bij Prinzmetal angina pectoris verkrampen de kransslagaders plotseling.

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