Abnormal spatial QRS-T angle predicts mortality in patients undergoing dobutamine stress echocardiography for suspected coronary artery disease
Jonathan A. Lipton(1), Stefan P. Nelwan(1), Ron T. van Domburg(1), Jan A. Kors(2), Abdou Elhendy(3), Don Poldermans(1)
1. Deparment of Cardiology, Erasmus Medical Center, Rotterdam, Netherlands, 2. Department of Medical Informatics, Erasmus University, Rotterdam, Netherlands, 3. Department of Cardiology, Marshfield Clinic, Marshfield, WI, USA
Objective: To investigate the association between (cardiac) mortality and QRS-T angle in patients undergoing dobutamine-atropine stress echocardiography (DSE) for evaluation of known or suspected coronary disease.
Methods: Between 1990 and 2003, 2347 patients underwent DSE for evaluation of coronary disease at the Erasmus Medical Center. Echocardiographic images were analyzed offline using a 16-segment, five-point scoring model for regional function. 12-lead resting ECG’s were analyzed and patients were grouped in three categories according to their spatial QRS-T angle: normal (0-105°), borderline (105-135°), and abnormal (135-180°).
Results: Mean age was 61±13 years, 66% were male, 32% had hypertension, 26% had hypercholesterolemia, 28% were smokers and 12% were diabetic. During a mean follow-up of 7±3.4 years 26.5% (623) of the patients died; 15.3% (359) died due to a cardiac cause. Abnormal QRS-T angle (135-180°) was present in 21% of the patients. Abnormal QRS-T angle was a predictor of cardiac death (HR 3.2[2.6-4.1]) and all cause mortality (HR 2.2[1.8-2.6]). After multivariate analysis abnormal and borderline QRS-T angle, peak wall motion score, age, male gender, history of diabetes, history of heart failure, smoking and hypertension were independent predictors of (cardiac) death.
Conclusion: Abnormal QRS-T angle is an independent predictor of (cardiac) death in patients undergoing DSE. Abnormal QRS-T angle should be considered as a risk factor in stable patients evaluated for coronary disease.
Submitted to journal of Coronary Artery Disease