Significance of a Fragmented QRS Complex Versus a Q Wave in Patients With Coronary Artery Disease

Abstract

Background-Q waves on a 12-lead ECG are markers of a prior myocardial infarction (MI). However, they may regress or even disappear over time, and there is no specific ECG sign of a non-Q-wave MI. Fragmented QRS complexes (fQRSs), which include various RSRЈ patterns, without a typical bundle-branch block are markers of altered ventricular depolarization owing to a prior myocardial scar. We postulated that the presence of an fQRS might improve the ability to detect a prior MI compared with Q waves alone by ECG. Methods and Results-A cohort of 479 consecutive patients (meanϮSD age, 58.2Ϯ13.2 years; 283 males) who were referred for nuclear stress tests was studied. The fQRS included various morphologies of the QRS (Ͻ120 ms), which included an additional R wave (RЈ) or notching in the nadir of the S wave, or Ͼ1 RЈ (fragmentation) in 2 contiguous leads, corresponding to a major coronary artery territory. The Q wave was present in 71 (14.8%) patients, an fQRS was present in 191 (34.9%) patients, and an fQRS and/or a Q wave was present in 203 (42.3%) patients. Sensitivity, specificity, and the negative predictive value for myocardial scar as detected by single photon emission computed tomography analysis were 36.3%, 99.2%, and 70.8%, respectively, for the Q wave alone; 85.6%, 89%, and 92.7%, respectively, for the fQRS; and 91.4%, 89%, and 94.2%, respectively, for the Q wave and/or fQRS. Conclusions-The fQRS on a 12-lead ECG is a marker of a prior MI, defined by regional perfusion abnormalities, which has a substantially higher sensitivity and negative predictive value compared with the Q wave.

Fragmented QRS Is Predictive of Myocardial Dysfunction, Pulmonary Hypertension and Severity in Mitral Stenosis

“…marker of depolarization abnormality and myocardial scar in patients with coronary artery disease (Varriale and Chryssos 1992;Das et al 2006;Michael et al 2007;Das et al 2009). Additionally, fQRS has been demonstrated as a marker of increased mortality and arrhythmic events in patients with ischemic cardiomyopathy ), arrhythmogenic right ventricular dysplasia/cardiomyopathy (Peters et al 2008) and Brugada syndrome (Morita et al 2008).…”

“…Recently, the presence of fragmented QRS (fQRS) in ECG was accepted as a marker of myocardial fibrosis (Das et al 2009). Association between conduction delay caused by myocardial scar and fQRS have been described in coronary artery disease (Das et al 2006). To our knowledge, the electrocardiographic demonstration of fQRS and its role as diagnostic indicator of the severity of mitral stenosis has not been described previously.…”

The Association Between Fragmeted QRS and ICD Shocks in patients with Left Ventricular Systolic Heart Failure

“…Tüm hastalara rutin biyokimya (açlık kan şekeri, kreatinin, kan elektrolitleri) ve tam kan sayımı yapıldı. Çalışmalardan ilkinde sensitivite ve negative prediktivitenin fQRS için q dalgasından daha yüksek olduğu saptanmıştır (2). Diğer çalışma-da ise bir öncekine göre fQRS'in sensitivite daha az fakat oldukça spesifik olduğu saptanmıştır.…”

“…(4) Bu bulgulara ek olarak godolinyumlu kardiyak manyetik rezonans görüntüleme ile yapılan çalışmalarda fQRS skar alanlarını ön gördürmüştür (16)(17). Diğer çalışmalarda miyokardiyal perfüzyon bozukluğu ve skar dokusu ile fQRS arasında ilişki saptanmıştır (2)(3)(4)(5)18). İlginç bir bulgu olarak koroner arter hastalığı ve dilate kardiyomyopati tanılı ve ventriküler aritmisi olan hastalarda endokardiyal haritalamada skar alanlarının çevresinde fragmante intrakardiyak elektrokardiogramlar alınmış-tır (19)(20).…”

“…Buna ek olarak manyetik rezonans görüntüleme çalışmaları miyokardiyal skar ve fQRS arasında ilişki saptamıştır (1)(2)(3)(4)(5). Bazı çalışmalarda fQRS kardiyak kötü sonlanımlar ile ilişkili olduğu bulunmuştur (4,(6)(7).…”