Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We wanted to determine whether there are episodes of myocardial ischemia in hypertensive patients with a normal coronary angiogram. ST-segment analysis on 24-h-Holter ECG was performed in 35 patients (18 males/17 females; mean age 54.6 +/- 10.4 years) with essential arterial hypertension (systolic/diastolic blood pressure 189.7 +/- 29/99.5 +/- 15 mm Hg). Left ventricular muscle mass (LVMM), enddiastolic volume (EDV), and the relation of mass to volume (M/V) were measured by ventriculography. Stenosis of coronary vessels was excluded by angiography in all patients. In 16 of 35 patients we observed 6.63 +/- 6.73 episodes of transient myocardial ischemia (ST-segment depressions greater than or equal to 1 mm, duration of the episode greater than or equal to 1 min). The duration of the episodes was 29.3 +/- 58.1 min, the maximal ST-segment depression 1.6 +/- 0.6 mm. In 95% of the episodes the patients did not experience any angina pectoris ("silent ischemia"). The degree of left ventricular muscle mass did not differ in hypertensive patients with and without transient myocardial ischemia (185.2 +/- 48.3 vs 227.1 +/- 71.5 g/m2). Systolic wall stress i.e. afterload was significantly higher in hypertensive patients with ST-segment depressions than in those without. In conclusion, these results demonstrate that transient myocardial ischemia often occurs in hypertensive patients. It seems that left ventricular hypertrophy by itself (myocardial factor) does not play a major role. Transient myocardial ischemia occurs mainly in hypertensive patients with eccentric myocardial hypertrophy i.e. low mass-volume ratio and high systolic wall stress. Accordingly, the occurrence of transient myocardial ischemia in hypertensive patients seems to be dependent on the myocardial energy demand.
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PMID:[Transient myocardial ischemia in hypertensive patients]. 252 20

Transient myocardial ischemia in postoperative hypertension is relatively common with coronary artery bypass surgery. This study examines the effect of hypertension during reperfusion of transiently ischemic myocardium. The animal model was open chest pigs with myocardial ischemia induced by the occlusion of the left anterior descending coronary artery for 30 min followed by 2 hr of reperfusion. A normotensive control group was compared with animals rendered hypertensive with phenylephrine during the ischemic and reperfusion times. In the hypertensive group, systolic blood pressure was raised from 106 to 161 mm Hg and peripheral vascular resistance from normal to 3600 dyn-sec-cm-5. Regional left ventricular wall thickness, mitochondrial function, sarcoplasmic reticulum Ca2+ uptake, tissue calcium, water content, and hemorrhage were evaluated. Compared to controls the hypertensive group had (1) loss of systolic wall thickening with increased diastolic wall thickness in the reperfused zone, (2) intramyocardial hemorrhage in the area of reperfusion, (3) significant impairment of oxidative phosphorylation by mitochondria isolated from the reperfused zone, (4) a marked reduction in the rate of Ca2+ uptake by sarcoplasmic reticulum vesicles, and (5) an increase in ischemic tissue calcium. Thus, hypertension associated with revascularization of acutely ischemic myocardium may accentuate myocardial damage.
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PMID:The adverse effect of systemic hypertension following myocardial reperfusion. 660 May 6

This case study describes myocardial ischemia and stunning after the topical application of phenylephrine-soaked pledgets (0.25%) in a 63-year-old female undergoing elective endoscopic sinus surgery. The patient had no previous history of cardiovascular disease or illicit drug use. Transient myocardial ischemia was associated with acute hypertension, chest pain, and S-T segment changes 4 minutes after pledget placement. Angiography revealed normal coronary blood flow and severe left ventricular systolic and diastolic dysfunction. Follow-up echocardiography demonstrated improved left ventricular function within 1 week and total resolution of dysfunction by 4 weeks after ischemia.
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PMID:Myocardial ischemia and stunning induced by topical intranasal phenylephrine pledgets. 943 94