Stress echocardiography for the diagnosis of ischaemia in hypertensives

Abstract

Exercise treadmill electrocardiography and myocardial perfusion imaging are commonly used in non-invasive tests for the detection of myocardial ischaemia. Unfortunately there are limitations in the assessment of hypertensive patients since these tests frequently provide false-positive results, particularly in those subjects with left ventricular hypertrophy. In order to investigate the utility of stress echocardiography in hypertensive patients we assessed 173 subjects undergoing this investigation in our department. Of these, 66 had had coronary angiography within 6 months. Thirty subjects were hypertensives, 17 with left ventricular hypertrophy, and 36 normotensives. Patients with a 70% or greater stenosis at coronary angiography were deemed to have sufficient disease to cause myocardial ischaemia. The overall sensitivity of stress echocardiography for detecting myocardial ischaemia was 83% with a specificity of 77%. For the hypertensive group alone the sensitivity was 93% and specificity 73%. The normotensives had a sensitivity of 76% with a specificity of 80%. In conclusion, in this group of hypertensives stress echocardiography had a favourable specificity and this was not significantly different from that of normotensive subjects.