Predictive value of a fragmented QRS complex in diagnosing patients with myocardial ischemia

Abstract

Background A fragmented QRS complex (fQRS) is caused by conduction abnormalities of the ventricle secondary to myocardial ischemia and/or scar in patients with myocardial infarction. However, the implications of the fQRS in the development of coronary artery disease with myocardial ischemia in those without a scar remain unknown. Methods We studied electrocardiograms (ECGs) obtained from 150 patients (60.5 ± 8.5 years, 102 men) with myocardial ischemia, which was confirmed by performing both, a nuclear exercise stress test and coronary angiography. We also studied ECGs obtained from 601 patients (58.5 ± 10.0 years, 315 men) who showed a negative nuclear exercise stress test (control group). Patients in whom the nuclear exercise stress test showed a myocardial scar were excluded. Results An fQRS was more commonly observed in patients with myocardial ischemia (n = 48, 32.0%) than in the control group (n = 133, 22.1%) ( P = 0.011). The sensitivity, specificity, positive, and negative predictive values of fQRS in diagnosing myocardial ischemia were 32.0, 77.9, 26.5, and 82.1%, respectively. The fQRS (odds ratio 1.580, 95% confidence interval 1.020‐2.446, P = 0.040) was an independent predictor of myocardial ischemia after adjusting for age, sex, current smoking habits, ST‐T changes on ECG, as well as histories of hypertension, diabetes, and dyslipidemia. Moreover, the fQRS showed an incremental prognostic value over conventional risk factors ( χ 2 = 5, P = 0.032) and over a combination of conventional factors and ST‐T changes ( χ 2 = 9, P = 0.014). Conclusions The fQRS is a moderately sensitive and independent predictor of myocardial ischemia.

The relationship between fragmented QRS and mortality in without reversible defects patients with scintigraphical myocardial infarction diagnosis

“…In a study monitoring MI and/or ischemia without any differentiation between transmural and non-transmural types on MPS in patients with coronary artery disease, fQRS was reported to be correlated with cardiac events (MI, need for revascularization, and cardiac death) [6]. Unlike the present study, another study which, due to cardiac events, excluded patients with scar tissue on MPS reports and included ischemic patients who underwent a coronary angiogram (CAG) reported that fQRS was a moderately sensitive and independent marker for ischemia diagnosis and showed a higher prognostic value compared to conventional risk factors [10]. Similarly, various studies showing that fQRS is likely to be an important marker for poor prognosis in ischemic patients have been published.…”

“…Some studies have also reported that fQRS displays higher sensitivity in displaying scar tissue compared to the Q-wave [8]. In the existing literature, although the number of studies on the relationship between perfusion-induced mortality and fQRS is limited, many of these studies deal with its relationship with cardiovascular mortality [6,[10][11][12][13]. In a study monitoring MI and/or ischemia without any differentiation between transmural and non-transmural types on MPS in patients with coronary artery disease, fQRS was reported to be correlated with cardiac events (MI, need for revascularization, and cardiac death) [6].…”

Diagnostic Accuracy of Number of Fragmented QRS Leads in Prediction of Cardiac Resynchronization Therapy Response in Patients With Heart Failure

“…15 Similar studies in patients undergoing nuclear stress testing have shown that fQRS is associated with older scars. 16,17 For that reason, several studies have been conducted to investigate the relation between fQRS and CRT response.…”

The Predictive Value of Fragmented QRS Complex in Diagnosis of Myocardial Ischemia

“…The ventricular myocardium's inhomogeneous activation is represented by a fragmented QRS (fQRS) complex found on a 12-lead ECG (2).…”