Journal of Invasive Cardiology

Accordingly, we aimed to investigate the effects of admission serum creatinine on coronary and myocardial blood flow and short- and long-term prognosis in ST-segment elevation myocardial infarction (STEMI) patients undergoing primary PCI.

Patients and Methods

Study population. Ours was a retrospective observational study. Data on 495 consecutive STEMI patients at Beijing Friendship Hospital who underwent primary coronary intervention within 12 hours of the onset of symptoms were retrospectively collected between October 2004 and November 2007. The diagnosis of STEMI was based on the following: > 30 minutes of continuous chest pain; ST elevation > 2.0 mm in ≥ 2 contiguous electrocardiographic (ECG) leads; creatinine kinase level equivalent to > 2 times the upper limit of normal. Patients with earlier coronary artery bypass graft surgery (CABG), hemodialysis therapy, pain-to-balloon time > 12 hours, presence of any chronic inflammatory-autoimmune disease and known malignancy were excluded from this study. The study protocol was reviewed and approved by the ethical committee at Beijing Friendship Hospital. Informed consent to participate in this study was obtained from all patients.

Blood was drawn in the emergency room or coronary care unit before primary coronary angiography. The patients were initially divided into two groups based on their admission serum creatinine level. The normal range of serum creatinine was between 0.6–1.3 mg/dl, thus the normal serum creatinine group was defined as < 1.3 mg/dl (normal group) and as ≥ 1.3 mg/dl for the elevated serum creatinine group (elevated group).

Coronary angiography. All patients received an intravenous (IV) bolus injection of 2,000 U of heparin prior to angiography. Diagnostic coronary angiography was performed via the femoral or radial approach using the Judkins technique. After an additional IV or intra-arterial bolus injection of 6,000 U of heparin, PCI was performed. Primary PCI was done using the conventional technique, and coronary stents were used without restrictions. The IRA was the only target of the procedure. Intra-aortic balloon counterpulsation (IABP) was performed in cases of hemodynamic instability. TIMI grade 3 coronary flow in the treated vessel with a residual stenosis < 20% was considered successful PCI. Serum creatinine kinase was measured serially every 2 hours after revascularization until the peak value was achieved. Patients received conventional drug treatment according to individual need, which was determined by the attending physician. The patients with stents received anticoagulation with a clopidogrel and aspirin regimen (clopidogrel 75 mg once a day and aspirin 100 mg once a day).