OBJECTIVE To investigate whether exercise-induced hypertension in successfully repaired adult post-coarctectomy patients is associated with hypertension on 24-h blood pressure measurement and increased left ventricular mass. METHODS One hundred and forty-four consecutive post-coarctectomy patients (mean age 31.5 years, range 17-74 years; mean age at repair 7.9 years, range 0-45 years) from three tertiary referral centres were studied using ambulatory blood pressure monitoring, treadmill exercise testing and echocardiography. RESULTS Of the 144 patients, 27 (19%) were known to have sustained hypertension, based on their history, and all were on antihypertensive medication. However, 32 (27%) of the remaining 117 patients showed elevated mean daytime systolic blood pressure readings at 24-h ambulatory blood pressure monitoring (systolic blood pressure > or = 140 mmHg). Of the remaining 85 patients with normal mean daytime systolic blood pressure, 18 patients (21%) had exercise-induced hypertension (maximal exercise systolic blood pressure > 200 mmHg). Mean daytime systolic blood pressure was higher in the exercise-induced hypertensive patients compared to the normotensive patients with normal exercise blood pressure (134 +/- 5 versus 129 +/- 7 mmHg, P = 0.008). By multivariate analysis, both maximal exercise systolic blood pressure (P = 0.007) and resting systolic blood pressure (P < 0.0001) were independently associated with mean daytime systolic blood pressure. Maximal exercise systolic blood pressure had no independent predictive value for left ventricular mass (P = 0.132). CONCLUSIONS In adult post-coarctectomy patients, maximal exercise systolic blood pressure is independently associated with mean daytime systolic blood pressure at ambulatory blood pressure monitoring. In this study no independent predictive value of maximal exercise systolic blood pressure for left ventricular mass could be demonstrated.