TRPM4 and Arrhythmia: Most were in the GLA gene (n = 6), followed by 2 patients with variants in TTR, PRKAG2 and LAMP2 respectively and finally one with CPT2. A total of 0.6% of cases (n = 8) had LP/P variants in genes associated with non-HCM cardiomyopathy (two in LMNA, and DSG2, one in JUP) or arrhythmias (one in SCN5A, RYR2, TRPM4 respectively).