One study finds no association between early repolarization and cardiac mortality

One study finds no association between early repolarization and cardiac mortality

One study finds no association between early repolarization and cardiac mortality: The benign nature of early repolarization has been questioned in a few recent studies [1,2]. Now here is one study which found no significant association between any of the components of early repolarization and cardiac mortality [3]. They studied the resting electrocardiograms of 29,281 ambulatory persons. With the PR interval as the isoelectric line, they defined J wave as an upward deflection, a slur as a conduction delay on the QRS downstroke and ST segment elevation as components of early repolarization. Though they found that components of early repolarization to be associated with decreased cardiovascular mortality, this was not significant after adjustment for age. This was because the patterns were more common in young individuals. J waves or slurring was more prevalent in those with than those without ST segment elevation and ST segment elevation occurred more in those with J waves or slurs (P<0.001). The early repolarization pattern was more common in young individuals, males, blacks and those with bradycardia, except when it was seen only in inferior leads.

A meta analysis included  29 studies with 182,135 subjects in the general population and 14 studies with 8087 subjects in physically active individuals [4]. Worldwide prevalence of early repolarization pattern in general population was 11.6%. They found higher incidence of 17% in males vs 6.2% in females. Prevalence of early repolarization pattern in physically active individuals was 33.9%.

References

1. Michel Haïssaguerre, Nicolas Derval, Frederic Sacher, Laurence Jesel, Isabel Deisenhofer, Luc de Roy, Jean-Luc Pasquié, Akihiko Nogami, Dominique Babuty, Sinikka Yli-Mayry, Christian De Chillou, Patrice Scanu, Philippe Mabo, Seiichiro Matsuo, Vincent Probst, Solena Le Scouarnec, Pascal Defaye, Juerg Schlaepfer, Thomas Rostock, Dominique Lacroix, Dominique Lamaison, Thomas Lavergne, Yoshifusa Aizawa, Anders Englund, Frederic Anselme, Mark O’Neill, Meleze Hocini, Kang Teng Lim, Sebastien Knecht, George D Veenhuyzen, Pierre Bordachar, Michel Chauvin, Pierre Jais, Gaelle Coureau, Genevieve Chene, George J Klein, Jacques Clémenty. Sudden cardiac arrest associated with early repolarization. N Engl J Med. 2008 May 8;358(19):2016-23.
2. Gi-Byoung Nam, You-Ho Kim, Charles Antzelevitch. Augmentation of J waves and electrical storms in patients with early repolarization. N Engl J Med. 2008 May 8;358(19):2078-9.
3. Abhimanyu Uberoi, Nikhil A Jain, Marco Perez, Anthony Weinkopff, Euan Ashley, David Hadley, Mintu P Turakhia, Victor Froelicher. Early Repolarization in an Ambulatory Clinical Population. Circulation. 2011 Nov 15;124(20):2208-14.
4. Ji HY, Hu N, Liu R, Zhou HR, Gao WL, Quan XQ. Worldwide prevalence of early repolarization pattern in general population and physically active individuals: A meta-analysis. Medicine (Baltimore). 2021 Jun 4;100(22):e25978.