Exercise and arrhythmic risk in TMEM43 p.S358L arrhythmogenic right ventricular cardiomyopathy.

BACKGROUND: High-level exercise has been associated with a malignant phenotype in desmosomal and genotype-negative forms of arrhythmogenic right ventricular cardiomyopathy (ARVC). This is the first study to examine this issue with ARVC secondary to the TMEM43 p.S358L mutation. OBJECTIVE: The purpose of this study was to evaluate the impact of exercise on arrhythmic risk and cardiac death in TMEM43 p.S358L ARVC. METHODS: Individuals with the TMEM43 p.S358L mutation enrolled in a prospective registry who had received a primary prevention implantable cardioverter-defibrillator (ICD) were invited to complete the modified Paffenbarger Physical Activity Questionnaire to assess their physical activity in the year before their ICD implantation. Time-to-event analyses using unadjusted and adjusted Cox proportional hazards models evaluated associations between physical activity and first appropriate ICD discharge secondary to malignant ventricular arrhythmia or cardiac death. RESULTS: In 80 subjects with the TMEM43 p.S358L mutation, exercise ≥9.0 metabolic equivalent of task (MET)-hours/day (high level) in the year before ICD implantation was associated with an adjusted 9.1-fold increased hazard of first appropriate ICD discharge (there were no deaths) relative to physical activity <9.0 MET-hours/day (moderate level) (95% confidence interval [CI] 3.3-24.6 MET-hours/day; P < .001). The median age from birth to first appropriate ICD discharge was 58.5 years (95% CI 56.5-60.5 years) vs 35.8 years (95% CI 28.2-43.4 years) (P < .001) in subjects in moderate- and high-level exercise groups, respectively. CONCLUSION: Exercise ≥9.0 MET-hours/day is associated with an increased risk of malignant ventricular arrhythmias in the TMEM43 p.S358L subtype of ARVC. Extrapolating these data, we suggest molecular testing be offered in early childhood to inform exercise choices reflective of the genotype.

Torticollis as Presentation for Atypical Kawasaki Disease Complicated by Giant Coronary Artery Aneurysms.

Kawasaki disease (KD) is an acute systemic vasculitis of childhood. The diagnosis can be made in a patient who presents with a prolonged high fever and meeting at least four of five criteria including polymorphous rash, mucosal changes, extremity changes (including swelling and/or palmar and plantar erythema), bilateral nonsuppurative conjunctivitis, and unilateral cervical lymphadenopathy. Atypical KD refers to patients who have not met the full criteria and in whom atypical features may be present. We discuss a case of a 6-year-old male who presented to the Emergency Department with torticollis. A series of investigations for elevated inflammatory markers revealed dilated coronary artery aneurysms on echocardiogram, and thus he was diagnosed with atypical KD. His only other criteria were bilateral nonsuppurative conjunctivitis and a prior brief febrile illness. He was treated with high-dose intravenous immune globulin (IVIG) and low-dose aspirin. Low-molecular-weight heparin and atenolol were added due to the presence of giant aneurysms.