Transient myocardial ischemia in hypertensive heart disease.

This study determined whether episodes of myocardial ischemia occur in hypertensive patients with normal coronary angiograms. ST-segment analysis during 24-hour Holter electrocardiography was determined in 48 patients (24 men and 24 women, mean age 54.6 +/- 10.4 years) with essential arterial hypertension (systolic/diastolic blood pressure 189.7 +/- 29/99.5 +/- 15 mm Hg). The thickness of left ventricular posterior wall and septum were measured with echocardiography. Stenosis of coronary vessels were excluded on angiography in all patients. In 24 of 48 patients, 12.8 +/- 13.8 episodes of transient myocardial ischemia (ST-segment depression greater than or equal to 1 mm, duration of the episode greater than or equal to 1 minute) were observed. The duration of the episodes was 48.1 +/- 69.93 minutes and the maximal ST-segment depression was 1.91 +/- 0.82 mm. In 95% of the episodes the patients did not experience any angina pectoris. The degree of left ventricular wall thickness did not differ in hypertensive patients with and without transient myocardial ischemia (septum thickness 11 +/- 2 mm). It is concluded that transient myocardial ischemia often occurs in hypertensive patients. Thus, left ventricular hypertrophy does not appear to play any important role. The underlying cause appears to be the impaired coronary dilation capacity, i.e., vascular alterations.