USEFULNESS OF ISCHEMIC RESPONSE TO MENTAL STRESS IN PREDICTING SILENT-MYOCARDIAL-ISCHEMIA DURING AMBULATORY MONITORING

To evaluate the relation of mental stress-induced ischemia to silent i schemia on ambulatory monitoring, 46 patients with stable coronary art ery disease underwent standardized laboratory mental stress and exerci se treadmill testing according to National institutes of Health protoc ol during which left ventricular election fraction (EF) was determined using the nuclear VEST. Life stress, type A behavior, and hostility w ere determined using standard interviews, Subsequently, 48-hour ambula tory electrocardiographic monitoring was performed. Twenty-three patie nts (50%) had an ischemic response (left ventricular EF decrease great er than or equal to 5%) to mental stress, which was associated with am bulatory ischemia (13 of 19 with ambulatory ischemia had mental stress -induced ischemia vs 10 of 27 without ambulatory ischemia, p = 0.04). Left ventricular EF response to mental stress was a significant predic tor of ambulatory ischemia independent of EF response to exercise (F = 4.8, p = 0.03), patients with mental stress-induced ischemia had long er total duration (31.4 +/- 57.0 vs 8.3 +/- 18 minutes, p = 0.06) and more frequent episodes of ambulatory ischemia (3.1 +/- 4.6 vs 0.9 +/- 1.9 episodes, p = 0.03), Life stress, type A behavior, and hostility w ere not associated with prevalence or severity of ambulatory ischemia, In conclusion, an ischemic response to mental stress is significantly associated with higher prevalence, longer duration, and more frequent episodes of ambulatory ischemia.