Usefulness of Paradoxical Systolic Blood Pressure Increase After Exercise as a Predictor of Cardiovascular Mortality

Exercise treadmill testing (ETT) is a well-accepted examination for patients with suspected coronary artery disease (CAD), and exercise induced ST-segment deviation is commonly used for CAD detection. However, recent evidence shows that systolic blood pressure (SBP) changes during and after exercise were associated with CAD severity, risk of acute myocardial infarction and stroke, new-onset hypertension, and even cardiovascular mortality. We retrospectively assessed 3,054 patients referred for ETT in 1996. Blood pressure and heart rate were recorded at rest, during peak exercise, and 1 and 3 min after exercise. SBP at 3 min of recovery equal to or higher than that at 1-min of recovery was defined as paradoxical SBP increase. These patients were categorized into 4 groups according to ETT ST-segment change and postexercise SBP change. After 10 years of follow-up, 346 patients (11%) died, with 129 (4%) dying from cardiovascular disease (CVD). Among the 4 groups, patients with ischemic ST-segment change and paradoxical SBP increase were associated with a higher risk for mortality, with odds ratios of 1.86 (95% confidence interval 1.31 to 2.65) for all-cause mortality and 3.18 (95% confidence interval 1.94 to 5.20) for CVD mortality, respectively. Patients with isolated paradoxical SBP increase still had a higher risk of CVD mortality (odds ratio 1.80, 95% confidence interval 1.70 to 3.04), even after controlling other cardiovascular risk factors. In subgroup analysis of 346 mortality subjects, patients with ischemic ST-segment change and paradoxical SBP increase would be more likely to die from CVD. In conclusion, compared with ischemic ST-segment change, paradoxical SBP increase after exercise is an important and significant predictor of CVD mortality.