Grant: Project Grant

Usually rare, LQTS is a treatable hereditary heart rhythm condition, which if unrecognized may cause sudden cardiac death. Northern BC First Nations likely have the highest rate in the world, 15 times higher than expected. For over 10 years, our team has partnered with the Gitxsan Community to understand the effect of the common KCNQ1 gene mutation, identifying more than 140 carriers, and enrolling more than 800 community participants. We have learned that other genetic factors can increase risk, and certain times in life may have higher risk than others. Our data suggests young women of childbearing years have the highest risk for sudden death. However, children over a year of age may be spared from the fatal effects until they reach adulthood. Treatment with beta blockers is used in all ages to prevent risk of sudden cardiac death. The problem is that this standard treatment to reduce risk may have the side effect of predisposing to low blood sugar, especially in young children. Furthermore, another genetic factor common in the population (CPT1A P479L) may also increase risk of low blood sugar. A third risk factor is the KCNQ1 mutation causing LQTS can also lead to increased insulin secretion in the pancreas, further risking low blood sugar. Four children in Northern BC have now presented with severe episodes of low blood sugar, all with LQTS and CPT1A P479L, while on treatment with beta-blockers. This emerging information has implications for safe management of infants and children with LQTS in Northern BC. Priority attention will be focused on infancy, childhood, pregnancy, and for all women of childbearing years for 1) risk of cardiac event 2) evidence of treatment complication resulting in potentially damaging low blood sugar. We will also focus on children to explore their lived experiences with the condition and its management. Information from this study will provide evidence for the development of effective and acceptable management strategies.