Impact of Serum Phosphorus Levels on Outcomes After Implantation of Drug-Eluting Stents in Patients on Hemodialysis.

BACKGROUND: Elevated serum phosphorus level is an important risk factor for cardiovascular death in general patients on hemodialysis (HD). However, the effect of serum phosphorus levels on outcomes after drug-eluting stent (DES) implantation in HD patients is unknown.Methods and Results:This was a post-hoc study of the OUCH study series, a series of prospective multicenter registries of HD patients who underwent DES implantation comprising 359 patients from 31 centers in Japan. Patients were categorized into 3 groups according to their preprocedural serum phosphorus levels. The 1-year clinical outcomes of the 336 patients treated for de novo lesions were evaluated. Compared with patients with high (>5.5 mg/dL; n=65) or normal (3.5-5.5 mg/dL; n=219) serum phosphorus levels, those with low serum phosphorus levels (<3.5 mg/dL; n=52) had significantly fewer target lesion revascularization events (13.9% vs. 16.9% vs. 1.9%; P=0.0090) and major adverse cardiac and cerebrovascular events (29.2% vs. 31.1% vs. 13.5%; P=0.032). Multivariate logistic regression analysis revealed that low serum phosphorus level was an independent negative predictor for major adverse cardiac and cerebrovascular events (adjusted odds ratio, 0.31; 95% confidence interval, 0.12-0.70; P=0.0036). CONCLUSIONS: Lowering of serum phosphorus levels beyond the current recommended range may be considered in HD patients who undergo DES implantation.

Usefulness of Everolimus-Eluting Coronary Stent Implantation in Patients on Maintenance Hemodialysis.

The outcomes of second-generation drug-eluting stent (DES) are unknown in patients on maintenance hemodialysis (HD) although HD has been reported as a strong predictor of adverse outcome after the first-generation DES implantation. The OUCH-PRO Study is a prospective multicenter single-arm registry design to study clinical and angiographic outcomes after everolimus-eluting stent (EES). Patients who underwent maintenance HD were prospectively enrolled at the time of elective coronary intervention using EES. Quantitative coronary angiography was performed in an independent core laboratory. The primary end point was the occurrence of target vessel failure (TVF) defined as cardiac death, myocardial infarction (MI), and target vessel revascularization at 1 year. A total of 123 patients were enrolled and 161 EES were implanted. The TVF rate at 1 year was 18% (4% cardiac death, 0% MI, 17% target vessel revascularization). No stent thrombosis was documented. Other clinical events at 1 year were 3% noncardiac death, 3% stroke, and 9% non-target-vessel revascularization. Late lumen loss in stent was 0.37 ± 0.63 mm at 8 months. In conclusion, EES had a high TVF rate and great late lumen loss in patients on HD compared with previous huge EES data in non-HD patients.

Clinical and angiographic outcomes of paclitaxel-eluting coronary stent implantation in hemodialysis patients: A prospective multicenter registry: The OUCH-TL study (outcome in hemodialysis of TAXUS Liberte).

BACKGROUND: The outcome of percutaneous coronary intervention (PCI) has been reported to be poor in hemodialysis (HD) patients even in the drug-eluting stent era. We have reported relatively poor outcomes after sirolimus-eluting stent implantation in the OUCH study. METHODS: The OUCH-TL study is a prospective, non-randomized, single-arm registry designed to assess the results of paclitaxel-eluting stent (PES) in HD patients with follow-up quantitative coronary angiography analysis. The primary endpoint was the occurrence of target-vessel failure (TVF) defined as cardiac death, myocardial infarction (MI), and target-vessel revascularization (TVR) at 12 months. RESULTS: A total of 119 patients with 154 lesions were enrolled (one withdrawal). Mean age was 65±10 years, male gender was 79%, 89% of cases had stable coronary disease. Diabetic nephropathy was diagnosed in 61% of the patients. American College of Cardiology/American Heart Association type B2/C accounted for 96% of lesions and 22.7% of lesions were treated with Rotablator (Boston Scientific Corporation, Natick, MA, USA). Rates of TVF, death, MI, stent thrombosis and TVR at 12 months were 20.2%, 5.9%, 5.0%, 1.4%, and 12.6%, respectively. TVR was performed in 8.4% of the patients up to 12 months. Late loss in-stent was 0.48±0.61mm, and late loss in-segment was 0.37±0.61mm at 9 months. Binary restenosis in-stent was 10.3% and in-segment was 14.5%. CONCLUSIONS: Outcomes of PES implantation in hemodialysis patients appears comparable to those of non-hemodialysis patients.

Safety margin of minimized contrast volume during percutaneous coronary intervention in patients with chronic kidney disease.

Maximum allowable contrast dose (MACD) calculated as body weight × 5/serum creatinine has been a standard contrast dye volume (CV) used to decrease contrast-induced acute kidney injury. Recent advances in intravascular ultrasound-guided percutaneous coronary intervention (PCI) can dramatically minimize CV. The safe threshold when using an extremely low-dose CV is unknown. This study was designed as a multicenter, retrospective study of chronic kidney disease (CKD) patients with estimated glomerular filtration rate (eGFR) <30 ml/min/1.73 m(2) undergoing elective PCI. We divided the patients into three groups according to following criteria: (1) low dose, CV/eGFR ratio <1.0; (2) medium dose, CV/eGFR ratio ≥1 and

A novel technique for catheter engagement of protruding aorto-ostial stent.

We present a case of stenoses in the right coronary artery with a previously deployed stent showing gross protrusion into the aorta. Despite difficulty in cannulation of a guiding catheter into the coronary artery, percutaneous intervention was accomplished using a novel technique to engage the protruding stent.

A case with successful retrograde stent delivery via AC branch for tortuous right coronary artery.

The retrograde approach is a novel technique of percutaneous coronary intervention for chronic total occlusion. This technique has improved the success rate of guidewire passage through the occlusion. In the retrograde approach, a microcatheter and balloon are delivered through a retrograde channel. However, it is difficult for a stent to pass through collateral arteries. We report a case of coronary artery stenosis in a markedly tortuous right coronary artery for which a drug-eluting stent was delivered retrogradely via the atrial circumflex branch.

A case of CTO treated with minimum use of contrast media.

The retrograde approach is a novel technique for improving the success rate of guidewire passage through chronic total occlusion (CTO). In addition, this technique, especially when intravascular ultrasound-guided reverse controlled antegrade and retrograde subintimal tracking is employed, may help the operator to save on the contrast media used. In the case reported here, only 10 ml of contrast media was used in percutaneous coronary intervention for CTO.

Sirolimus eluting coronary stent implantation in patients on maintenance hemodialysis: the OUCH study (outcome of cypher stent inhemodialysis patients).

BACKGROUND: Pivotal studies on drug-eluting stents have excluded hemodialysis (HD) patients. No quantitative coronary angiography (QCA) analysis has been reported. METHODS AND RESULTS: The OUtcome of Cypher stent in Hemodialysis patients (OUCH) Study is a prospective non-randomized single-arm registry designed to assess the results of sirolimus-eluting stents in HD patients, with follow-up QCA in an independent core laboratory. The primary endpoint was the occurrence of target-vessel failure (TVF) defined as cardiac death, myocardial infarction (MI), and target-vessel revascularization (TVR) at 1 year. A total of 117 patients were enrolled. The TVF rate was 24.9% (2.6% cardiac death, 1.4% MI, 23.9% TVR), and stent thrombosis was documented in 1 patient (0.9%). Coronary calcification was a predictor of TVF. Late lumen loss (LLL) averaged 0.69±0.93mm. The histogram of LLL showed that a total of 76% of lesions were distributed the same normally as that in normal renal function (average LLL 0.20±0.29mm), but 24% of lesions were outliers (average LLL 2.07±0.62mm). CONCLUSIONS: This report describes different clinical and QCA results in HD patients as higher TVF rate, different predictive factors, and different histogram of LLL compared with normal renal function. The different histogram of LLL was the existence of many outliers with the same average and the same deviation, suggesting the loss of sirolimus had an effect on a significant number of HD patients.

Endothelin-1 prolongs intracellular calcium transient decay in neonatal rat cardiac myocytes.

Endothelin-1 (ET-1) is involved in the development of cardiac hypertrophy and heart failure. We investigated the effects of ET-1 on intracellular calcium transient and its mechanisms. Neonatal rat cardiomyocytes were prepared and calcium transient was measured using fura-2. Treatment with ET-1 for 48 h prolonged calcium transient decay. In the presence of thapsigargin, ET-1 did not alter calcium transient decay. On the other hand, the prolonged calcium transient decay was maintained even when sodium was removed from the bath solution. These results indicate that ET-1-induced prolongation of calcium transient decay is mainly due to the suppression of calcium uptake by sarcoplasmic reticulum, but not inhibition of the sodium/calcium exchanger. Northern blotting analysis revealed that sarcoplasmic reticulum ATPase (SERCA2) mRNA was decreased in ET-1-treated cardiomyocytes, and that this decrease was inhibited by BQ-123 but not by BQ-788. Moreover, pretreatment with chelerythrine partially restored the ET-1-induced decrease in SERCA2 mRNA, whereas phorbol 12-myristate 13-acetate markedly reduced SERCA2 gene expression. Real-time RT-PCR analysis showed abundant ETA receptor gene expression in cardiomyocytes. ET-1 reduces SERCA2 gene expression through the ETA receptor and PKC pathway, and prolongs intracellular calcium transient decay. Specific inhibition of the ETA receptor may be a possible therapeutic strategy for improving cardiac performance.

A prospective multicenter registry of 0.010-inch guidewire and compatible system for chronic total occlusion: the PIKACHU registry.

OBJECTIVES: The aim of this study was to evaluate the safety and effectiveness of a 0.010-inch guidewire and a balloon catheter for treatment of chronic total occlusion (CTO). BACKGROUND: Pathological studies have shown that 60-70% of CTO lesions have microchannels of sizes equal to or less than 0.010 inch. METHODS: The PIKACHU registry is a prospective, multicenter registry study. A 0.010-inch guidewire had to be used as the first guidewire to attempt to pass the CTO lesion. The primary endpoint was device success using a 0.010 system. RESULTS: A total of 141 patients with 141 lesions were enrolled. The median duration of occlusion was 9 months (range 3-156). Average guiding catheter size was 5.8 +/- 0.7 Fr. and TRI was 76.6 %. CTOs were mostly between 10-20 mm long, observed in 53 occlusions. There were 107 lesions (75.9%) with bending of more than 45 degrees. Calcification was seen in 91 lesions (64.5%). A 0.010-inch guidewire was successfully passed through in 97 of 141 lesions (68.8%). A 0.010-inch guidewire compatible balloon catheter was passed in 87 of the 97 lesions (88.7%) and final PCI success was achieved in all the cases. The overall clinical success rate was 87.9% (124/141). No MACE or bleeding complications were observed. CONCLUSION: The PIKACHU registry data suggest that the 0.010-inch system is safe and practicable for treatment of CTO lesions.