MR Evaluation of Arrhythmogenic Right Ventricular Cardiomyopathy in Pediatric Patients

The aim of our study was to correlate the findings of three MR imaging sequences with the clinical findings of possible arrhythmogenic right ventricular cardiomyopathy in pediatric patients. Twenty-six consecutive pediatric patients underwent MR imaging with ECG-gated non-breath-hold spin-echo T1-weighted non-fat-suppressed and fat-suppressed sequences. The MR images were evaluated for thinning or fat signal in the right ventricular wall and for enlargement or increased trabeculation of the right ventricle or right ventricular outflow tract. Cine MR imaging was used to assess wall motion abnormalities. Cardiac biopsy was performed in 17 patients. Biopsy results and other clinical findings suggesting arrhythmogenic right ventricular cardiomyopathy were tabulated. Two MR imaging studies were of poor quality as a result of arrhythmias, and one study was incomplete. In the 23 remaining patients, there were (mean +/- SD) 1.5 +/- 1.0 and 0.8 +/- 1.0 findings of possible arrhythmogenic right ventricular cardiomyopathy in the non-fat-suppressed and the fat-suppressed sequences, respectively. Fat-compatible signal in the myocardium was detected in 16 (70%) of 23 non-fat-suppressed studies and in five (22%) of 23 fat-suppressed studies (p = 0.003). The non-fat-suppressed sequence had a higher sensitivity (75% vs 43%) and a lower specificity (38% vs 75%) for fatty infiltration than did the fat-suppressed sequence when correlated with the biopsies. The linear correlation between all MR findings and all clinical diagnostic criteria, including biopsy, was better for the combination of cine and both T1 sequences (r = 0.58) than for the non-fat-suppressed (r = 0.53) or fat-suppressed (r = 0.46) T1 sequences alone. MR imaging showed moderate correlation with the clinical criteria in the diagnosis of arrhythmogenic right ventricular cardiomyopathy

Carvedilol in children with cardiomyopathy: 3-year experience at a single institution

Carvedilol reduces mortality and hospitalization in adults with congestive heart failure. Limited information is available about its use in children. We reviewed the medical records of 24 children with dilated cardiomyopathy and left ventricular ejection fraction of ≤40%, who were treated with carvedilol as adjunct therapy to angiotensin-converting enzyme inhibitors, digoxin and diuretics. Carvedilol was initiated 14.3 ± 23.3 (mean ± SD) months after the diagnosis of cardiomyopathy. Mean age at initiation of therapy was 7.2 ± 6.4 years. The mean initial and maximum doses were 0.15 ± 0.09 and 0.98 ± 0.26 mg/kg/day. Adverse effects occurred in 5 patients (21%). Two patients (8%) required discontinuation of the drug within 5 weeks of the initial dose. The remaining 22 patients tolerated carvedilol for a mean follow-up period of 26.6 ± 14.7 months. Among these 22 patients, mean left ventricular ejection fraction improved from 24.6 ± 7.6% to 42.2 ± 14.2% ( p < 0.001), and mean sphericity index from 0.86 ± 0.11 to 0.74 ± 0.10 ( p < 0.001). New York Heart Association functional class improved in 15 patients (68%). One patient (4%) died and 3 (14%) were transplanted. Carvedilol, in addition to standard therapy for dilated cardiomyopathy in children improves cardiac function and symptoms; it is well tolerated, with minimal adverse effects, but close monitoring is necessary as it might worsen congestive heart failure and precipitate asthma. Control studies are necessary to assess the effect of carvedilol on mortality and hospitalization rates