Prevention of contrast-induced nephropathy in diabetic patients with impaired renal function: a randomized, double blind trial of sodium bicarbonate versus sodium chloride-based hydration.

AIMS: Diabetes mellitus and decreased renal function are important risk factors for contrast-induced nephropathy (CIN) in which oxidative stress damage may play a role. Alkalinization with sodium bicarbonate (NaHCO3) has been proposed as a means of reducing free-radical mediated renal injury; however, the effectiveness of NaHCO3 treatment to prevent CIN in high-risk patients remains uncertain. METHODS: We performed a prospective, randomized, double blind, sodium chloride (NaCl) hydration-controlled study of NaHCO3 in 120 diabetic patients with impaired renal function (serum creatinine ≥100 µmol/L) undergoing an elective procedure with use of low-osmolar contrast media. The primary endpoint was the incidence of CIN defined as creatinine increase of ≥25% and/or ≥44 µmol/L within 2 days after contrast. Secondary end-points were maximal changes in serum creatinine and estimated glomerular filtration rate. Urine F2-isoprostane levels were also assessed as measure of oxidative stress. RESULTS: There were no significant group differences in baseline characteristics except for the marginally lower age of the NaHCO3 treated patients (63 ± 11 vs. 67 ± 10 years; p=0.05). CIN occurred in 7 (11.5%) and 5 (8.5%) patients of the NaHCO3 and NaCl groups, respectively (p=0.76; incidence rate ratio 1.35; 95% CI 0.37-5.41). No significant differences were seen in secondary outcome measures and changes in the parameter of oxidative stress. CONCLUSIONS: In diabetic patients with renal function impairment sodium bicarbonate does not confer protection against contrast-induced nephropathy greater than sodium chloride-based hydration. Its specific role in mitigating oxidative stress damage in CIN is also not supported by our data.

Angiographic surrogate end points in drug-eluting stent trials: a systematic evaluation based on individual patient data from 11 randomized, controlled trials.

OBJECTIVES: We sought to validate 4 angiographic measures as potential surrogates for clinical restenosis (target lesion revascularization [TLR]) after stent implantation. BACKGROUND: Given the low revascularization rates with drug-eluting stents (DES), an angiographic surrogate of TLR is desirable to reduce the sample size required to demonstrate efficacy in future trials of antirestenosis devices. METHODS: We evaluated 4 potential angiographic measures (late loss [LL] and percent diameter stenosis [%DS], both in-stent and in-segment) as a surrogate for TLR at 1 year. From 11 multicenter, prospective randomized stent trials, 9 comparing DES with bare-metal stents (BMS) and 2 comparing different DES, individual data on 5,381 patients with a single treated lesion and follow-up angiography at 6 to 9 months were analyzed. RESULTS: By 4 well-defined criteria of surrogacy, LL and %DS strongly predicted the risk of TLR, with in-segment %DS being the most highly predictive (approximately 0.95). Differences in TLR risk were fully explained statistically by their differences in LL or %DS, although LL as a surrogate was dependent on vessel size whereas %DS was not. However, because of the curvilinearity of the logistic model, trials comparing 2 effective DES can have significant differences in mean LL and %DS but small expected differences in TLR risk, especially at the lower ranges of LL and %DS. CONCLUSIONS: From in-stent and in-segment LL and %DS measures, logistic models can reliably estimate TLR rates for DES and BMS. These angiographic measures are thus suitable surrogate markers for clinical stent efficacy and can be used as primary end points in future DES trials to significantly reduce sample size.

Short- and long-term outcomes after stent-assisted percutaneous treatment of saphenous vein grafts in the drug-eluting stent era.

Percutaneous treatment of saphenous vein graft (SVG) lesions has been associated with higher rates of periprocedural complications and restenosis compared with non-SVG lesions. Whether these outcomes are similar in contemporary clinical practice, particularly when drug-eluting stents are used, is unknown. We evaluated outcomes of 110 consecutive patients who were treated with stent-assisted percutaneous coronary intervention for 145 SVG lesions (drug-eluting stents used in 91.0% of lesions). Embolic protection devices were used in 52.1% of treated grafts. Adverse events were recorded up to 1 year. Major or minor periprocedural myocardial necrosis occurred in 11 patients (10.9%). At 1-year clinical follow-up, we observed 13 myocardial infarctions (13.7%), 8 target lesion revascularizations (8.4%), 18 target vessel revascularizations (19.0%), 2 stent thromboses (2.1%), and 7 deaths (7.4%). The incidence of major adverse cardiac events, defined as death, myocardial infarction, or target vessel revascularization, was 30.5% at 1 year. By multivariable analysis, the presence of thrombus inside the graft before the procedure and the length of the stented segment were independent predictors of major adverse cardiac events at 1 year (hazard ratio for thrombus 4.07, 95% confidence interval 1.90 to 8.68, p = 0.0003; hazard ratio per millimeter of stented length 1.02, 95% confidence interval 1.01 to 1.03, p = 0.025). In conclusion, our data show that patients with SVG lesions remain a high-risk subgroup with worse outcomes after percutaneous coronary intervention compared with native vessel disease even in the era of drug-eluting stents.

Contrast-induced nephropathy.

Contrast induced nephropathy (CIN) is an iatrogenic disorder, resulting from exposure to contrast media. Contrast-induced hemodynamic and direct cytotoxic effects on renal structures are highly evident in its pathogenesis, whereas other mechanisms are still poorly understood. CIN is typically defined as an increase in serum creatinine by either > or =0.5 mg/dl or by > or =25% from baseline within the first 2-3 days after contrast administration. Although rare in the general population, CIN has a high incidence in patients with an underlying renal disorder, in diabetics, and the elderly. The risk factors are synergistic in their ability to produce CIN. The best way to prevent CIN is to identify the patients at risk and to provide adequate peri-procedural hydration. The role of various drugs in prevention of CIN is still controversial and warrants future studies. Despite remaining uncertainty regarding the degree of nephrotoxicity produced by various contrast agents, in current practice non-ionic low-osmolar contrast media are preferred over the high-osmolar contrast media in patients with renal impairment.

Gender-specific outcomes after sirolimus-eluting stent implantation.

OBJECTIVES: We examined the impact of gender on outcomes of patients undergoing percutaneous coronary intervention using sirolimus-eluting stents (SES). BACKGROUND: Although gender-specific differences in outcome after implantation of bare-metal stents (BMS) have been described, there are no data assessing outcomes of women treated with SES. METHODS: We performed a patient-level pooled analysis from 4 randomized SES versus BMS trials (RAVEL [Randomized Comparison of a Sirolimus-Eluting Stent with a Standard Stent for Coronary Revascularization], SIRIUS [SIRolImUS-coated Bx Velocity balloon expandable stent in the treatment of patients with de novo coronary artery lesions], E-SIRIUS [Sirolimus-eluting stents for treatment of patients with long atherosclerotic lesions in small coronary arteries], and C-SIRIUS [Canadian study of the sirolimus-eluting stent in the treatment of patients with long de novo lesions in small native coronary arteries]) and analyzed outcomes as a function of gender. RESULTS: Of 1,748 patients, 1,251 were men and 497 were women. A total of 878 patients were randomized to SES (629 men and 249 women), and 870 patients were randomized to BMS (622 men and 248 women). Compared with men, women were older and more frequently had diabetes mellitus, hypertension, and congestive heart failure. Although overall clinical outcomes were similar in both genders, treatment with SES was associated with significant (p < 0.0001) reductions in rates of in-segment binary restenosis both in women (6.3% vs. 43.8%) and in men (6.4% vs. 35.6%), resulting in a significant reduction in 1-year major adverse cardiac events, driven by a lower incidence of target lesion revascularization/target vessel revascularization in both genders. By multivariable analysis, female gender was not an independent predictor of in-segment binary restenosis or clinical outcomes regardless of stent type. CONCLUSIONS: In this analysis, despite less favorable baseline clinical and angiographic features in women compared with men, the angiographic and clinical benefits of SES were independent of gender.

An evaluation of fluoroscopy time and correlation with outcomes after percutaneous coronary intervention.

OBJECTIVE: We evaluated short-term prognosis and resource utilization of consecutive patients treated with percutaneous coronary intervention (PCI) as a function of fluoroscopy time. BACKGROUND: Advances in interventional cardiology are reflected in the growing complexity of PCI leading to an increasing use of fluoroscopic guidance. The relationship between fluoroscopy time and in-hospital outcomes after PCI has not been addressed. METHODS: In a retrospective analysis of a prospectively collected database including a total of 9,650 patients, the mean fluoroscopy time was 18.3 +/- 12.2 minutes. Outcomes were stratified by fluoroscopy time. RESULTS: Compared to patients within the 75th percentile, those with prolonged fluoroscopy time were older and had a higher prevalence of prior coronary artery bypass surgery (CABG), chronic renal insufficiency, peripheral arterial disease, type B2/C lesions, and baseline TIMI flow 0-2. Patients with prolonged fluoroscopy time had higher rates of in-hospital death (3.3% vs. 0.3%; p <0.0001), emergent CABG (2.1% vs. 0.3%; p = 0.0001), stent thrombosis (2.9% vs. 1.3%; p = 0.17), retroperitoneal hematoma (0.9% vs. 0.2%; p = 0.01), and contrast-induced nephropathy (6.7% vs. 4.5%; p = 0.03). Resource utilization was significantly higher (p <0.0001) in patients with prolonged fluoroscopy time. By multivariate analysis, prolonged fluoroscopy time was most strongly associated with prior CABG (OR = 2.39), ostial lesion (OR = 2.87), severe lesion calcification (OR = 2.14), baseline TIMI flow 0-2 (OR = 3.71) (all p <0.0001), lesion eccentricity (OR = 1.96; p = 0.0063), and peripheral arterial disease (OR = 1.91; p = 0.0068). CONCLUSIONS: Prolonged fluoroscopy time is associated with higher complexity of treated lesions and increased rates of periprocedural complications including early mortality, emergent CABG, contrast-induced nephropathy, and increased resource utilization.

A complex anomaly of systemic and pulmonary venous return associated with sinus venosus atrial septal defect.

This report describes a rare case of anomalous systemic and pulmonary venous return that was surgically corrected. It consisted of left inferior vena cava with hemiazygous continuation into the persistent left superior vena cava, partial anomalous pulmonary venous return from the right lung and sinus venosus atrial septal defect.