Background:Hypertrophic cardiomyopathy (HCM) can be associated with an abnormal exercise response. In adults with HCM, abnormal results on exercise stress testing are predictive of heart failure outcomes. Our goal was to determine whether an abnormal exercise response is associated with adverse outcomes in pediatric patients with HCM. Methods:In an international cohort study including 20 centers, phenotype-positive patients with primary HCM who were <18 years of age at diagnosis were included. Abnormal exercise response was defined as a blunted blood pressure response and new or worsened ST- or T-wave segment changes or complex ventricular ectopy. Sudden cardiac death (SCD) events were defined as a composite of SCD and aborted sudden cardiac arrest. Using Kaplan-Meier survival, competing outcomes, and Cox regression analyses, we analyzed the association of abnormal exercise test results with transplant and SCD event-free survival. Results:Of 724 eligible patients, 630 underwent at least 1 exercise test. There were no major differences in clinical characteristics between those with or without an exercise test. The median age at exercise testing was 13.8 years (interquartile range, 4.7 years); 78% were male and 39% were receiving beta-blockers. A total of 175 (28%) had abnormal test results. Patients with abnormal test results had more severe septal hypertrophy, higher left atrial diameter z scores, higher resting left ventricular outflow tract gradient, and higher frequency of myectomy compared with participants with normal test results (P<0.05). Compared with normal test results, abnormal test results were independently associated with lower 5-year transplant-free survival (97% versus 88%, respectively; P=0.005). Patients with exercise-induced ischemia were most likely to experience all-cause death or transplant (hazard ratio, 4.86 [95% CI, 1.69-13.99]), followed by those with an abnormal blood pressure response (hazard ratio, 3.19 [95% CI, 1.32-7.71]). Exercise-induced ischemia was also independently associated with lower SCD event-free survival (hazard ratio, 3.32 [95% CI, 1.27-8.70]). Exercise-induced ectopy was not associated with survival. Conclusions:Exercise abnormalities are common in childhood HCM. An abnormal exercise test result was independently associated with lower transplant-free survival, especially in those with an ischemic or abnormal blood pressure response with exercise. Exercise-induced ischemia was also independently associated with SCD events. These findings argue for routine exercise testing in childhood HCM as part of ongoing risk assessment.

Background-To assess the long-term results of the edge-to-edge mitral repair performed without annuloplasty in degenerative mitral regurgitation (MR). Methods and Results-From 1993 to 2002, 61 patients with degenerative MR were treated with an isolated edge-to-edge suture without any annuloplasty. Annuloplasty was omitted in 36 patients because of heavy annular calcification and in 25 for limited annular dilatation. A double-orifice repair was performed in 53 patients and a commissural edge-to-edge in 8. Hospital mortality was 1.6%. Follow-up was 100% complete (mean length, 9.2+/-4.21 years; median, 9.7; longest, 18.1). Survival at 12 years was 51.3+/-7.75%. At the last echocardiographic examination, MR >= 3+ was demonstrated in 33 patients (55%). At 12 years, freedom from reoperation was 57.8+/-7.21% and freedom from recurrence of MR >= 3+ was 43+/-7.6%. Residual MR > 1+ at hospital discharge was identified as a risk factor for recurrence of MR >= 3+ (hazard ratio, 3.8; 95% confidence interval, 1.7-8.2; P=0.001). In patients with residual MR <= 1+ immediately after surgery, freedom from MR >= 3+ at 5 and 10 years was 80+/-6% and 64+/-7.58%, respectively. Conclusions-In degenerative MR, the overall long-term results of the surgical edge-to-edge technique without annuloplasty are not satisfactory. Early optimal competence (residual MR <= 1+) was associated with higher freedom from recurrent severe regurgitation.