Early repolarization (ER) was first described in 1936 and has historically been considered a normal variant, but it is becoming more evident through further research that it is associated with an increased incidence of arrhythmic sudden cardiac arrest.
The term early repolarization (ER) is used to characterize an anomaly on the electrocardiogram (ECG) consisting of appearance of a J wave on a normal heart beat pattern. Historically, (ER) has been considered a marker of good health because it is more prevalent in athletes, younger persons, and at slower heart rates.
The Masonic Medical Research Laboratory (MMRL) scientists were at the forefront of research into this medical early repolarization pattern. It had long been ignored as just a harmless anomaly, but in reality was an indicator of that some forms of early repolarization could result in the development of life-threatening arrhythmias. The work published in The New England Journal of Medicine by the MMRL was groundbreaking in the study of this phenomena. Since then numerous studies have demonstrated that there is an increased risk for sudden cardiac death in patients who manifest an early repolarization pattern in the ECG.
Work performed by scientists at the MMRL has uncovered the cellular basis for the J wave in the ECG and has delineated the role of J waves in both health and disease. The MMRL team have shown that the J wave when accentuated can lead to both early repolarization and Brugada syndromes, which they collectively call the J wave syndromes. Both can results in sudden cardiac arrhythmic death.
The MMRL has identified 5 of 6 genes associated with early repolarization syndrome (ERS) and is working with clinicians worldwide to better define the clinical aspects of ERS and to develop new approaches to better diagnose and treat this deadly syndrome. One of the greatest challenges facing cardiologists today is to be able to risk stratify individuals with ER. Nearly 5% of the population exhibit some form of ER in the ECG. MMRL scientists are working with clinicians throughout the world to delineate strategies by which to identify subjects truly at risk for Sudden Cardiac Death.
The team at the MMRL have been awarded a $1 million NYSTEM grant to create a human model of ERS. They accomplish this by obtaining skin biopsies from subjects with ERS. They then transform fibroblasts from the skin biopsies into stem cells and direct the differentiation of the stem cells into cardiac cells. The end result is a cluster of heart cells that displays the properties of the patient’s heart, including the genetic defect responsible for ERS. These cells are the used to further understand the pathophysiology of the disease and to develop new drugs capable of reversing the damaging effects of the genetic mutation responsible for ERS.