Correlation of exercise response in repaired coarctation of the aorta to left ventricular mass and geometry

Abstract

The role of exercise testing to risk stratify patients with repaired coarctation of the aorta (CoA) is controversial. Concentric left ventricular (LV) hypertrophy, defined as an increase in the LV mass-to-volume ratio (MVR), is associated with a greater incidence of adverse cardiovascular events. The objective of the present study was to determine whether a hypertensive response to exercise (HRE) is associated with increased LVMVR in patients with repaired CoA. Adults with repaired CoA who had a symptom-limited exercise test and cardiac magnetic resonance imaging examination within 2 years were identified. A hypertensive response to exercise was defined as a peak systolic blood pressure >220 mm Hg during a symptom-limited exercise test. The LV mass and volume were measured using cardiac magnetic resonance by an investigator who was unaware of patient status. We included 47 patients (median age 27.3 years, interquartile range 19.8 to 37.3), who had undergone CoA repair at a median age of 4.6 years (interquartile range 0.4 to 15.7). Those with (n = 11) and without (n = 36) HRE did not differ in age, age at repair, body surface area, arm-to-leg systolic blood pressure gradient, gender, or peak oxygen uptake with exercise. Those with a HRE had a greater mean systolic blood pressure at rest (146 ± 18 vs 137 ± 18 mm Hg, p = 0.04) and greater median LVMVR (0.85, interquartile range 0.7 to 1, vs 0.66, interquartile range 0.6 to 0.7; p = 0.04) than those without HRE. Adjusting for systolic blood pressure at rest, age, age at repair, and gender, the relation between HRE and LVMVR remained significant (p = 0.001). In conclusion, HRE was associated with increased LVMVR, even after adjusting for multiple covariates.