Preliminary Study Of Abnormal Increase Of Postexercise Systolic Blood Pressure For Detection Of Coronary Artery Disease

OBJECTIVE: The study sought to evaluate the diagnostic value of abnormal increase of systolic blood pressure (SBP) after Treadmill exercise testing (TET) for detecting coronary artery disease (CAD) in patients with or without hypertension, and the relationship between coronary artery lesion and abnormal increase of SBP.METHODS: TET was conducted in 31 patients with normal blood pressure and 57 patients with hypertension, each of whom underwent selective coronary angiography (CAG). 40 of patients had significant narrowing of coronary artery (patients with CAD), the other 48 patients were used as control subjects. Blood pressure was measured at right cubitus every minute during the recovery phase (6 minutes) of TET. The abnormal increase of postexercise SBP was defined as an increase of > 10mmHg than earlier periods during the recovery phase of test. Diagnostic values of abnormal SBP, ST-segment depression criterion, and their combination in detecting CAD were analysised in each group. Postexercise SBPs of 30 healthy volunteers were studied as healthy controls. Plasm concentrations of vWF were detected in 30 patients to study the correlation between abnormal SBP increase and vWF.RESULTS: The postexercise SBPs of CAD patients increased or did not decline during the early recovery phase of TET. Abnormal increase of SBP had higher sensitivity (88%vs78%), specificity (79%vs56%, P<0.05), accuracy (83%vs66%, P<0.01), positive predict value (78%vs60%) and positive likely ratio (4.2vs1.77) than those ofST-segment depression for detecting CAD. Its accuracy increased with the severity of coronary artery lesion. The SBP index identified CAD more accurate in normotensive group. The combination of two indexes diagnosed CAD most accurately in patients with hypertension. There was no significant correlation between abnormal increase values of SBP and plasm concentrations of vWF.CONCLUSIONS: Abnormal increase of postexercise SBP may be a useful index for diagnosing CAD. Its accuracy increased with the severity of coronary artery lesion. The SBP index identified CAD more accurate than ST-segment depression criterion, especially in normotensive group. The combination of two indexes diagnosed CAD most accurately in patients with hypertension.