Sinoatrial Node Dysfunction and Deafness, also known as sandd, is related to sick sinus syndrome and syncope, and has symptoms including syncopal episode An important gene associated with Sinoatrial Node Dysfunction and Deafness is CACNA1D (Calcium Voltage-Gated Channel Subunit Alpha1 D). Affiliated tissues include heart, and related phenotypes are hearing impairment and bradycardia