Wellens' syndrome is an electrocardiographic manifestation of critical proximal left anterior descending (LAD) coronary artery stenosis in people with unstable angina. Originally thought of as two separate types, A and B, it is now considered an evolving wave form, initially of biphasic T wave inversions and later becoming symmetrical, often deep (>2 mm), T wave inversions in the anterior precordial leads.[1]
First described by Hein J. J. Wellens and colleagues in 1982 in a subgroup of people with unstable angina,[2] it does not seem to be rare, appearing in 18% of patients in his original study. A subsequent prospective study identified this syndrome in 14% of patients at presentation and 60% of patients within the first 24 hours.[3]
The presence of Wellens' syndrome carries significant diagnostic and prognostic value. All people in the De Zwann's study with characteristic findings had more than 50% stenosis of the left anterior descending artery (mean = 85% stenosis) with complete or near-complete occlusion in 59%. In the original Wellens' study group, 75% of those with the typical syndrome manifestations had an anterior myocardial infarction. Sensitivity and specificity for significant (more or equal to 70%) stenosis of the LAD artery was found to be 69% and 89%, respectively, with a positive predictive value of 86%.[4]
Wellens' sign has also been seen as a rare presentation of Takotsubo cardiomyopathy or stress cardiomyopathy.[citation needed]
The diagnosis is done via:[citation needed]