Short QT in a Cohort of 1.7 Million Persons: Prevalence, Correlates, and Prognosis

• DOI: 10.1111/anec.12157
• Publication Date: 2014-05-14T11:58:57Z
• Authors: Carlos Iribarren; Alfred D. Round; Jonathan A. Peng; Meng Lu; Arthur L. Klatsky; Jonathan G. Zaroff; Taylor J. Holve; Amit Prasad; Paul Stang
• Keywords: Short QT syndrome

Background Short QT syndrome (QTc ≤ 300 ms) is a novel hereditary channelopathy linked to syncope, paroxysmal atrial fibrillation, and sudden cardiac death. However, its epidemiological features remain unsettled. Objectives (1) To assess the prevalence of short in large population‐based sample; (2) evaluate demographic clinical correlates and; (3) determine prognosis. Methods A database 6.4 million electrocardiograms (ECGs) obtained between 1995 2008 among 1.7 persons was used. An internal, method for heart rate correction (QT creg ) used all ECGs with ≤300 ms were manually validated. Linked health plan databases covariate survival ascertainment. Results Of 6,387,070 ECGs, 1086 had an ECG machine‐read ms. Only 4% (45/1086) validated yielding 0.7 per 100,000 or 1 141,935 ECGs. At person level, overall 2.7 37,335. The factors independently significantly associated age over 65 years, Black race, prior history ventricular dysrhythmias, chronic obstructive pulmonary disease, ST‐T abnormalities, ischemia, bigeminy pattern, digitalis effect. After 8.3 years median follow‐up relative normal , after multivariate adjustment 2.6‐fold (95% confidence interval [CI] = 1.9–3.7) increased risk Conclusion extraordinarily rare significant abnormalities reduced survival.