Fragmented QRS complex predicts contrast-induced nephropathy and in-hospital mortality after primary percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction.

BACKGROUND: Contrast-induced nephropathy (CIN) is associated with increased mortality after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Recently, fragmented QRS complex (fQRS) on 12-lead electrocardiography has been introduced as a marker of cardiovascular disease and is associated with increased morbidity and mortality. HYPOTHESIS: fQRS on ECG is associated with CIN and in-hospital mortality after primary PCI in patients with STEMI.
METHODS: Eight hundred ninety-five patients with first STEMI treated by primary PCI were enrolled in the study. Patients were divided into 2 groups according to the presence or absence of fQRS as shown by 12-lead electrocardiography in the first 24 hours. fQRS was defined by presence of an additional R wave (R″), or notching of the S wave, or >1 R' in 2 contiguous leads. Patients were then reallocated to 2 groups according to presence or absence of postprocedural CIN, which was defined as a rise in serum creatinine of 0.5 mg/dL or a 25% increase from baseline value within 72 hours after the procedure.
RESULTS: Patients with a fQRS were older and had significantly lower left ventricular ejection fraction. CIN occurred in 77 (8.6%) patients. The prevalence of CIN and in-hospital mortality was significantly higher in the fQRS(+) group. In multivariate analysis, fQRS was found to be an independent predictor of CIN (odds ratio: 3.125, P = 0.029) and in-hospital mortality (odds ratio: 9.062, P = 0.009).
CONCLUSIONS: The fQRS is an independent predictor of postprocedural CIN and in-hospital mortality in STEMI patients.