Compared with the QRS 120-149 ms group , cardiac mortality was highest in the QRS 200 ms group ( hazard ratio [ HR ] 1.72 [ 95 % CI 1.35-2 .19 ] , P < .001 ) , independent of age , gender , New York Heart Association class , presence of atrial fibrillation , heart failure etiology , and left ventricular ejection fraction .