Beyond A and B: Exploring a Novel dynamic ECG change in Wellens Syndrome

Wellens syndrome was initially described in the early 1980s and is characterized by 2 high-risk electrocardiographic (ECG) patterns associated with critical stenosis of the left anterior descending artery (LAD). A prevailing theory suggests that Wellens' pattern A is underdiagnosed due to delays in clinical presentation; therefore, the most common finding upon arrival at the Emergency Department is pattern B, accounting for nearly 80% of cases. This suggests that pattern A often evolves prior to medical assessment. Alternatively, aligning with our study, we propose a dynamic model characterized by a distinct electrocardiographic transition between pattern A and B, electrophysiologically explained by ischemic vectoring shifting and supported by clinical observations where some patients do not complete the classic transition. We enrolled 51 patients with Wellens syndrome to assess serial electrographic changes and transitions, alongside analyzing demographics, cardiovascular risk factors, clinical past history, left ventricular ejection fraction, and revascularization outcomes. All cases underwent coronary angiography, which confirmed LAD involvement, consistent with Wellens' original description. Notably, an ECG transition from patterns A to B was documented within 6 to 12 hours in 18 patients (36%). All patients in our cohort achieved favorable clinical outcomes.