0282: Rest and exercise pulmonary hypertension in hypertrophic cardiomyopathy

Background Heart failure (HF) symptoms, related to pulmonary capillary hypertension, are frequent in hypertrophic cardiomyopathy (HCM). Pulmonary hypertension (PH) is the consequence of left ventricular (LV) diastolic pressure elevation and/or functional mitral regurgitation. We aimed to evaluate determinants and prognostic significance of rest and exercise in HCM. Methods and results We included 235 patients referred for clinical work-up of HCM. Rest pulmonary artery systolic pressure (PASP) was measurable in 214 (91%) patients (48±16 years, 161 males). A symptom-limited semi-supine bicycle exercise was carried out in 188 patients. PASP was measurable during exercise in 108 patients (57%). Resting PH (≥36mmHg) was present in 56 patients (26.2%) and exercise PH (≥60mmHg) in 38 patients (35.2%). Mutivariate correlates of rest PASP were sinus rhythm (β=–0.15, P=0.021), LV obstruction tract (LVOT) peak gradient (β=0.22, P=0.001) and left atrial volume (β=0.39, P Conclusion In patients with HCM, the main determinants of rest PH are sinus rhythm, LVOT peak gradient and left atrium volume. Determinants of exercise PH are rest PASP, grade of MR and rest LVOT gradient. Rest and exercise PH predict a poor outcome in HCM.