Phenotype/Genotype Relationship in Left Ventricular Noncompaction: Ion Channel Gene Mutations Are Associated With Preserved Left Ventricular Systolic Function and Biventricular Noncompaction: Phenotype/Genotype of Noncompaction.

Abstract Background Few data exist concerning genotype–phenotype relationships in left ventricular noncompaction (LVNC). Methods and Results From a multicenter French Registry, we report the genetic and clinical spectrum of 95 patients with LVNC, and their genotype–phenotype relationship. Among the 95 LVNC, 45 had at least 1 mutation, including 14 cases of mutation in ion channel genes. In a complementary analysis including 16 additional patients with ion channel gene mutations, for a total of 30 patients with ion channel gene mutation, we found that those patients had higher median LV ejection fraction (60% vs 40%; P Conclusions Ion channel gene mutations should be searched systematically in patients with LVNC associated with either bradycardia or biventricular noncompaction, particularly when LV systolic function is preserved. Identifying causative mutations is of utmost importance for genetic counselling of at-risk relatives of patients affected by LVNC.