Dynamic J-point elevation associated with bigeminy in a patient with early repolarization phenotype

This 54-year-old gentleman presented with stable angina. The 12-lead electrocardiogram (ECG) revealed inferolateral J-point elevation (0.2 mV in Lead II) and notching of the S-wave at rest with horizontal ST segments (early repolarization pattern). The ECG before any treatment is shown (Figure 1A). Coronary angiography demonstrated an aberrant circumflex artery origin, and a discrete mid-vessel stenosis was stented, apparently without complication. Four weeks later, he was resuscitated following ventricular fibrillation (VF) cardiac arrest. Serial biomarkers did not suggest an acute coronary syndrome, and repeat angiography revealed patent arteries. Cardiac magnetic resonance imaging demonstrated an area of late enhancement in the lateral wall suggestive of prior infarction. Our patient underwent implantable cardiac defibrillator (ICD) insertion. Subsequently, VF electrical storm was observed with multiple appropriate ICD discharges. Heart rhythm monitoring during one of these episodes is shown (Figure 1B, ECG Lead II). Note that the ventricular bigeminy and dynamic change in J-point amplitude precipitating polymorphic ventricular tachycardia. After the introduction of the Ito-blocker Quinidine, the J-point elevation reduces (not shown). In pathological early repolarisation, J-point elevation may reflect transmural gradients in the transient outward potassium current (Ito). We hypothesize that subclinical myocardial infarction with ventricular bigeminy provided substrate for re-entry in a patient with underlying pathological early repolarization. The full-length version of this report can be viewed at: http://www.escardio.org/Guidelines-&-Education/E-learning/Clinical-cases/Electrophysiology/EP-Case-Reports.