Abstract 17152: Prophylactic Left Cardiac Sympathetic Denervation for Patients with Long QT Syndrome and Beta Blocker Intolerance

Abstract

Introduction: Long QT Syndrome (LQTS) is a potentially lethal, but highly treatable cardiac channelopathy. Current treatment options include pharmacotherapy (mostly beta blockers), device therapy (mostly implantable cardioverter defibrillators (ICDs)), and/or left cardiac sympathetic denervation (LCSD) with the majority of patients requiring only beta blocker therapy. However, beta blockers are not without side effects and beta blocker intolerance can have a profoundly negative effect on a patient's quality of life. Heretofore, a prophylactic ICD has been utilized for the patient with LQTS who can not tolerate high dose beta blocker therapy. Here we examined the role of a prophylactic LCSD rather than an ICD for the LQTS patient with beta blocker intolerance. Methods: In this IRB-approved study, we retrospectively reviewed the electronic medical record for 58 patients (28 male (48%), mean age at diagnosis 9.6 ± 9 years (yrs), mean baseline QTc 524 ± 73 ms, 93% genotype positive) with LQTS who underwent LCSD at our institution from November 2005 through May 2011 (mean age at LCSD 14.0 ± 9.8 yrs). Results: Out of 58, 19 patients (33%; 15 female (79%) had LCSD as primary prevention because of beta blocker intolerance and were older at LQTS diagnosis (15.1 ± 8 vs 7.0 ± 9 yrs;.p=0.001), older at LCSD (20.5 ± 8 vs 10.9 ± 9 yrs; p<0.001), and had a shorter baseline QTc (493 ± 32 vs 539 ± 82 ms; p = 0.004) compared to the other 38 patients. Post-LCSD, 5/19 (26 %) had QTc-shortening of >30ms. With an average follow-up of 1.3 ± 0.8 yrs, none of these patients have experienced a post-LCSD cardiac event even though 7/19 (37%) had at least 1 LQTS-associated cardiac event. Qualitatively, there has been a dramatic improvement in quality of life following LCSD with subsequent decrease in beta blocker dose in 13 or discontinuation of beta blockers altogether in 5. Conclusions: Prophylactic LCSD may provide a beta blocker-reducing or even sparing strategy without increasing risk in carefully selected patients. However, LCSD should not be viewed as curative or an ICD-alternative for high-risk patients. Among appropriately selected patients who are failing to tolerate beta blocker therapy, LCSD may be an acceptable, quality of life improving alternative to an ICD and its associated comorbidities.