The aim of the study was to investigate the severity of coronary artery disease (CAD) in patients who had a planar QRS-T angle > 90 degrees versus ≤; 90 degrees.
Coronary angiography was performed in 1,229 consecutive patients. Obstructive CAD was diagnosed if there was > 50% obstruction of ≥ 1 major coronary artery. All QRS-T angle measurements were made from a 12-lead electrocardiogram by 2 authors who agreed on the measurement and who were blinded to the coronary angiographic findings. A QRS-T angle > 90 degrees was considered abnormal.
Obstructive CAD of 2 or 3 vessels was present in 309 of 495 patients (62%) with a planar QRS-T angle > 90 degrees and in 250 of 734 patients (34%) with a planar QRS-T angle ≤; 90 degrees (p < 0.0001). Stepwise logistic regression analyses showed that significant independent risk factors for 2- or 3-vessel CAD were age (odds ratio = 1.05), male gender (odds ratio = 1.8), black race (odds ratio = 0.34), unstable angina (odds ratio = 0.16), positive stress test (odds ratio = 3.0), hypertension (odds ratio = 3.0), dyslipidemia (odds ratio = 2.9), QRS-T angle (odds ratio = 7.2), left bundle branch block (odds ratio = 2.9), right bundle branch block (odds ratio = 0.17), smoking (odds ratio = 9.7), and body mass index ≥ 30 kg/m2 (odds ratio = 1.5).
The prevalence of 2- or 3-vessel obstructive CAD was significantly higher in patients with a planar QRS-T angle > 90degrees than in patients with a planar QRS-T angle ≤; 90 degrees (p < 0.0001).
Patients with suspected CAD and a planar QRS-T angle > 90 degrees should undergo a stress test for detection of myocardial ischemia and should be treated more aggressively with medical therapy.
Chandrasekar Palaniswamy, No Financial Disclosure Information; No Product/Research Disclosure Information