Long Qt Syndrome 15, also known as lqt15, is related to long qt syndrome 14 and ventricular tachycardia, catecholaminergic polymorphic, 3. An important gene associated with Long Qt Syndrome 15 is CALM2 (Calmodulin 2), and among its related pathways/superpathways are Activation of cAMP-Dependent PKA and Transmission across Chemical Synapses. Affiliated tissues include heart and heart-atrium, and related phenotypes are sinus bradycardia and prolonged qtc interval