RESUMO
OBJECTIVE: Contrast-induced nephropathy (CIN) is a common complication of diagnostic or interventional procedures that may arise from administration of intravascular contrast media. Recent studies have reported the thiol-disulfide ratio as a novel oxidative stress marker. Therefore, we investigated the role of thiol levels in predicting CIN in patients with ST-segment elevation myocardial infarction (STEMI) who had undergone primary percutaneous coronary intervention (PCI). METHODS: A total of 302 patients were enrolled in the study. CIN was defined as an increase in serum creatinine concentration ≥0.5 mg/dL compared with the admission value or a >25% relative rise during the first 48-72 hours after the procedure. To evaluate the relationship between thiol levels and CIN, the patients were divided into a CIN group and a non-CIN group. RESULTS: CIN occurred in 44 (15%) patients. Native thiol (274.8±84.7 µmol/L vs. 220.8±97.1 µmol/L, p=0.001) and total thiol (305.4±89.7 µmol/L vs. 260.1±102.1 µmol/L, p=0.009) levels were higher in patients within the non-CIN group. Disulfide (15.8±6.6 µmol/L vs. 19.6±8.4 µmol/L, p=0.002) levels, and mean disulfide/total thiol ratios (8.4±3.7 vs. 5.9±3.1, p=0.001) were higher in patients with CIN (+) group. In univariate analysis, the initial native thiol, total thiol, disulfide levels, and disulfide/total thiol ratio were found to have prognostic significance in the development of CIN. In the multivariate regression analysis, only the disulfide/total thiol ratio (OR=1.190; 95% CI: 1.090-1.300; p=0.001) was significantly and independently associated with CIN. The cutoff value of the disulfide/total thiol ratio to predict CIN on admission in patients with STEMI who underwent primary PCI was 7, with a sensitivity of 68.2% and a specificity of 79.8%. CONCLUSION: Our results suggest that thiol/disulfide homeostasis could be a good biochemical risk marker for CIN in STEMI patients who underwent primary PCI.
RESUMO
BACKGROUND: Recently fragmented QRS (fQRS) on electrocardiography (ECG) has been introduced as a predictor of myocardial scarring and myocardial ischemia in coronary artery disease (CAD). OBJECTIVE: The aim of this study was to investigate the relationship between fQRS and fractional flow reserve (FFR) results in patients with the intermediate degree of coronary artery stenosis. METHODS: A total of 301 consecutive patients who underwent coronary angiography (CAG) and FFR measurement for intermediate coronary artery stenosis were included in the study. The study patients were divided into two groups: the low FFR group (FFR value of ≤0.80) and normal FFR (FFR value of >0.80) group. Both groups were compared in terms of the presence of fQRS. RESULTS: Of 301 patients, fQRS was detected in 128 (42.5%) and low FFR was detected in 115 (38.2%). In the low FFR group, fQRS was significantly higher (P<0.001). Multivariate analysis showed that fQRS was an independent predictor of myocardial ischemia in patients with intermediate coronary stenosis (OR=7.202, CI 95%, 4.195-12.367; p<0.001). The presence of fQRS had 70% sensitivity and 74% specificity for the prediction of FFR≤0.80. CONCLUSION: In clinical practice, the presence of fQRS on ECG is associated with myocardial ischemia in patients with intermediate coronary stenosis.
