The ratio of contrast volume to glomerular filtration rate predicts outcomes after percutaneous coronary intervention for ST-segment elevation acute myocardial infarction.

OBJECTIVE: To assess the value of the ratio between contrast medium volume and glomerular filtration rate (CMGFRr) for prediction of development of contrast-induced nephropathy (CIN) and mortality in patients with ST-segment elevation acute myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI).

BACKGROUND: Renal function is a strong predictor of outcome in patients with STEMI. CIN may complicate the course of primary PCI in these patients.

METHODS: The study population included all 871 consecutive patients with STEMI without cardiogenic shock who underwent primary PCI at our center from January 1, 2001, to October 30, 2006. CIN was defined as an absolute increase in serum creatinine > 0.5 mg/dL or a relative increase >25% within 48 hr after PCI.

RESULTS: In-hospital CIN developed in 72 (8.3%) patients. On linear regression analysis, the following variables were independently associated with CIN: male sex (odds ratio [OR] = 0.42, 95% confidence interval [CI], 0.18-0.97, P = 0.04), GFR < 60 (OR = 3.6, 95% CI, 2.79-4.78, P < 0.0001), multivessel coronary artery disease (OR = 1.67, 95% CI, 1.08-2.58, P = 0.02), CMGFRr (OR = 1.53, 95% CI, 1.01-2.31, P = 0.04, for upper tertile vs. lower two tertiles), and Killip class > 1 (OR = 1.35, 95% CI, 1.03-1.76, P = 0.03). CMGFRr > 3.7 was a strong independent predictor of CIN (OR = 3.87, 95% CI, 1.72-8.68, P = 0.001). Twenty-six (2.9%) patients died at 1 month after PCI. The following variables were independently predictive of 1-month mortality: CMGFRr > 3.7 (OR = 3.3, 95% CI, 1.22-9.04, P = 0.018) and multivessel coronary artery disease (OR = 2.3, 95% CI, 1.28-4.07, P = 0.005).

CONCLUSION: The contrast medium-to-GFR ratio is a strong predictor of CIN and of 1-month mortality in patients undergoing primary PCI for STEMI.