Grant: Travel Awards - Institute Community Support

BACKGROUND: Phospholamban cardiomyopathy is a rare inherited cardiac condition, previously reported in the Netherlands, to be associated with poor long-term outcomes. We examined a series of Canadian patients with condition as the previous reported Dutch population. METHODS: Individuals with a phospholamban mutation were identified from 3 Inherited Arrhythmia Clinics across Canada. Cardiac investigations, including electrocardiograms, Holter monitoring, cardiac ultrasound (echocardiogram) and cardiac MRI, were reviewed for abnormalities. Family genetic screening allowed for the identification of affected and unaffected family members. RESULTS: Across Canada, 30 patients from 5 families were identified or screened by genetic testing for the phospholamban mutation. Fourteen patients had the pathogenic mutation, with 11 unaffected relatives and 5 with genetic testing in progress. The median age was 29 years (range 10-71 years) and 15 (50%) were female. Genotype-positive patients were more likely to have electrocardiogram abnormalities (i.e. low-voltage QRS, T-wave inversion) and abnormalities and cardiac function (i.e. identified on cardiac ultrasound or MRI). Among genotype-positive patients, individuals 45 years or older were more likely to have exaggerated findings, including electrocardiogram abnormalities, arrhythmias on Holter monitoring, and abnormalities in cardiac function, compared to their younger relatives. Five patients received an implantable cardioverter-defibrillator device for arrhythmias, and two patients were referred for heart transplantation. CONCLUSIONS: Phospholamban cardiomyopathy is a unique inherited heart condition that was first reported in the Netherlends, and has migrated to affect a number of Canadians. This type of cardiac condition should be considered in individuals with a certain electrocardiogram abnormalities and unexplained abnormalities in cardiac function.