Percutaneous coronary intervention causes increase of serum cystatin C concentration even in the patients with a low risk of contrast-induced nephropathy.

Contrast-induced nephropathy (CIN) is an important complication of coronary angiography (CAG) and percutaneous coronary intervention (PCI). The aim of this study was to examine the effect of CAG and PCI to renal function in patients with a low risk of CIN by measuring serum cystatin C concentration. The patients were classified into 3 groups; CAG group, elective PCI group, and emergency PCI group. Enrolment continued until 100 patients were included in each of the 3 groups. The exclusion criteria were as follows; (1) serum creatinine concentration >1.5 mg/dL, (2) age >80 years, (3) cardiogenic shock, (4) use of mechanical ventilation or intra-aortic balloon pump, (5) history of renal failure, and (6) quantity of contrast used > maximum radiographic contrast dose. Blood samples for serum cystatin C analysis were collected before and 3 months after the index procedure. Two patients in the CAG group, 4 patients in the elective PCI group, and 12 patients in the emergency PCI group developed CIN. Multivariate analysis identified the predictors of CIN: pre-procedural cystatin C concentration >1.04 mg/L, contrast volume >150 mL and emergency procedure. In the elective PCI group and emergency PCI group, serum cystatin C concentration was significantly increased 3 months after PCI procedure. Even patients with a low risk of CIN developed CIN after CAG and PCI, which caused increase of serum cystatin C concentration. We should become more aware of the possible development of CIN and avoid performing unnecessary CAG and PCI procedure as far as possible.

Restenosis after implantation of sirolimus-eluting stent begins suddenly, shows short term progression, and stops suddenly.

BACKGROUND AND PURPOSE: The peak of restenosis in patients implanted with bare metal stents (BMS) is thought to be 6 months after BMS implantation, but the development of restenosis with respect to time and the peak of restenosis in patients implanted with drug-eluting stents (DES) is not known. This study aims to reveal the rate of development of restenosis with respect to time in patients implanted with DES. METHODS: A total of 282 patients who underwent sirolimus-eluting stent (SES) implantation in native coronary arteries at our hospital were evaluated by serial quantitative angiography at 3 and 6 months, and based on the latter results, at 1 and 2 years after SES implantation. Clinical data were collected for up to 3 years. RESULTS: Three-year follow-up data were obtained for 261 patients. The 3-year incidence of clinically driven target-lesion revascularization (TLR) was 6.1% (16/261); of the 16 cases, 5 occurred at 3-month follow-up, 7 at 6-month angiographic follow-up, and 1 at 1-year follow up, respectively. While minimum lumen diameter (MLD) of these vessels that underwent TLR at 6 months decreased rapidly after the 3-month angiographic follow-up, MLD of the vessels with 50-70% stenosis at 6-month angiographic follow-up was almost unchanged at 1-year angiographic follow-up; however, 3 lesions required late (i.e. beyond 1 year) revascularization. CONCLUSIONS: It is difficult to predict SES restenosis by angiography. SES restenosis begins suddenly, shows short-term progression, and stops suddenly. However, treatment of de novo coronary stenosis with SES is associated with a sustained clinical benefit and a very low incidence of TLR.

Efficacy of thrombectomy for acute myocardial infarction-Special focus on its efficacy according to different infarct-related arteries.

BACKGROUND: The efficacy of thrombectomy during percutaneous coronary intervention (PCI) for ST-segment elevation acute myocardial infarction (STEMI) has not yet been fully evaluated. The aim of this retrospective study was to evaluate the usefulness of manual thrombectomy for STEMI and to clarify whether different infarct-related arteries (IRAs) influence the efficacy of thrombectomy. METHODS AND RESULTS: We enrolled 183 patients with STEMI who underwent PCI within 24h after onset between October 2001 and January 2004. We divided these patients into 2 groups, namely 88 patients who had undergone PCI after manual thrombectomy (Th+ group) and 95 patients who were treated with PCI alone (Th- group). The Th+ group had lower incidences of distal embolization and no-reflow phenomenon than the Th- group (6.8% vs. 27.4%, p=0.0003; and 5.7% vs. 23.2%, p=0.0009, respectively). The percentage of complete ST-segment resolution (STR) after PCI and left ventricular ejection fraction 6 months after the procedure were significantly higher in the Th+ group (43.2% vs. 20%, p=0.002; and 60.1% vs. 54.8%, p=0.004, respectively). Regarding different IRAs, the percentage of complete STR was significantly higher in patients with proximal left anterior descending coronary artery (LAD) and right coronary artery (RCA) lesions in the Th+ group (37.5% vs. 9.7%, p<0.05; and 59.5% vs. 30.3%, p<0.05, respectively). Incidences of adverse events were similar in both groups. CONCLUSIONS: Manual thrombectomy for STEMI can improve myocardial reperfusion after PCI and left ventricular function late after the procedure. With respect to different IRAs, manual thrombectomy for STEMI is more effective in proximal LAD and RCA lesions.

Prognostic significance of cystatin C in patients with ST-elevation myocardial infarction.

BACKGROUND: Cystatin C is reportedly a better endogenous marker of glomerular filtration rate than serum creatinine, so the prognostic value of cystatin C in patients with ST-elevation myocardial infarction (MI) was evaluated in the present study. METHODS AND RESULTS: A total of 71 patients who underwent percutaneous coronary intervention for ST-segment elevation MI <24 h from symptom onset were included. According to cystatin C level, patients were classified into 2 groups: (1) higher cystatin C group (n=33) and (2) lower cystatin C group (n=38). There was a trend toward more in-hospital deaths in patients with the higher cystatin C level compared with the lower cystatin C level group (15.2% vs 2.6%, P=0.06). Mean duration of clinical follow-up was 5.6 +/-2.8 months. There was no significant difference in death, reinfarction, disabling stroke or target lesion revascularization between the 2 groups. However, a higher incidence of rehospitalization for congestive heart failure was observed in patients with the higher cystatin C level than in those with the lower cystatin C level (15.2% vs 0%, P=0.01). CONCLUSIONS: Cystatin C may be associated with more cardiovascular events, mainly rehospitalization for congestive heart failure, after percutaneous coronary intervention in patients with ST-elevation MI.