The prognostic value of a QRS score during exercise testing

Abstract

SummaryBackground: Values of a QRS score have been positively related to the number of narrowed coronary arteries and to the extent of myocardial ischemia in radionuclide imaging techniques.Hypothesis: This study was conducted to evaluate the potential prognostic information of abnormal values of this QRS score during treadmill exercise testing in patients with established coronary artery disease (CAD).Methods: In all, 309 patients (258 men, 51 women, mean age 56.1 ± 10.0 years) with documented CAD, underwent a treadmill exercise test and coronary arteriography at baseline. Subsequently, they were prospectively followed to a maximum of 36 months (mean follow-up 23 ± 13 months, median 25 months).Results: During the follow-up period, 20 patients (6.5%) died from acute myocardial infarction. Abnormal QRS score values were found to be significantly and independently associated with cardiac mortality (QRS ≤ Ϫ4: relative risk 11.7; 95% confidence interval = 2.5-55.4; p = 0.002).Conclusions: Taking into consideration the importance of exercise testing in the management of ischemic heart disease, the use of this QRS score could be of clinical value in predicting the outcome of patients with documented CAD.

Duration of treadmill exercise testing combined with QRS score predicts adverse cardiac outcome at long-term follow-up

“…These values are significantly higher than the respective ones for ST-segment depression, thus denoting the superior diagnostic value of QRS score that has also been documented in challenging patient groups with unreliable ST-segment response during exercise, including patients with previous myocardial infarction or patients who have undergone revascularization procedures. Furthermore, QRS score is significantly correlated to the number of obstructed coronary arteries and the number of exercise-induced myocardial perfusion defects in scintigraphic studies [5,6], whereas recent trials have shown its significant and independent association with cardiac mortality [4].…”

“…This QRS score has also been shown to estimate prognosis, as it is significantly and independently associated with cardiac mortality [4].…”

“…The Athens QRS score is a TET-derived index, based on exercise-induced changes in the amplitude of Q, R, and S waves in leads aVF and V 5 which has significantly higher sensitivity and specificity than conventional ST-segment shifts for the assessment of restenosis after percutanerous transluminal coronary angioplasty or ischemia after coronary artery bypass grafting, significant relationship with the extent of ischemia, as assessed by thallium-201 scintigraphy, and an additive diagnostic accuracy when combined with classical ST-segment criteria for the detection of CAD [4][5][6][7][8][9]. This QRS score has also been shown to estimate prognosis, as it is significantly and independently associated with cardiac mortality [4].…”

Relationship between QRS duration and prognosis in non-ST-segment elevation acute coronary syndrome

“…Several authors have demonstrated that myocardial ischemia increases QRSd: Elhendly et al reported that in patients with known or suspected coronary artery disease, QRSd correlated positively with the severity of the underlying ischemia [13]; Michaelides et al showed a proportional relationship between the exerciseinduced QRS prolongation and the number of coronary arteries with significant stenosis [14]. Left ventricle dysfunction [5,13], increased left ventricular size and muscle mass [15], myocardial fibrosis [16] and involvement of the conduction system in the ischemic area [17] also prolong QRSd.…”

The impact of novel exercise criteria and indices for the diagnostic and prognostic ability of exercise testing

“…It was shown that "Athens score" has proved to be an important alternative in estimating the heart patients and defining their prognosis [34]. Quite recently, in a continuous effort to improve the clinical value of ET, a novel prognostic index was invented, called "M score" (Michaelides score) [35].…”