sirolimus and Renal-Artery-Obstruction

Because of higher acute and long-term success rates compared with balloon angioplasty alone, percutaneous stent implantation has become an accepted therapy for the treatment of atherosclerotic renal artery stenosis. Restenosis rates after successful renal stent placement vary from 6 up to 40%, depending on the definition of restenosis, the diameter of the treated vessel segment and comorbidities. The safety and efficacy of drug-eluting stents for the treatment of renal-artery stenosis is poorly defined. The recently published GREAT study is the only prospective study, comparing bare-metal and sirolimus-coated low profile stent systems in renal artery stenosis, showing a relative risk reduction of angiographic binary in-stent restenosis by 50%. This is an opinion paper on indications, current treatment options and restenosis rates following renal artery stenting and the potential use of drug-eluting stents for this indication.

Topics: Drug-Eluting Stents; Humans; Immunosuppressive Agents; Recurrence; Renal Artery Obstruction; Sirolimus; Treatment Outcome

To evaluate the patency of sirolimus-eluting stents (SES) compared to bare-metal stents (BMS) in the treatment of atherosclerotic renal artery stenosis (RAS).. Between November 2001 to June 2003, 105 consecutive symptomatic patients (53 men; mean age 65.7 years) with RAS were treated with either a bare-metal (n=52) or a drug-eluting (n=53) low-profile Palmaz-Genesis peripheral stent at 11 centers in a prospective nonrandomized trial. The primary endpoint was the angiographic result at 6 months measured with quantitative vessel analysis by an independent core laboratory. Secondary endpoints were technical and procedural success, clinical patency [no target lesion revascularization (TLR)], blood pressure and antihypertensive drug use, worsening of renal function, and no major adverse events at 1, 6, 12, and 24 months.. At 6 months, the overall in-stent diameter stenosis for BMS was 23.9%+/-22.9% versus 18.7%+/-15.6% for SES (p=0.39). The binary restenosis rate was 6.7% for SES versus 14.6% for the BMS (p=0.30). After 6 months and 1 year, TLR rate was 7.7% and 11.5%, respectively, in the BMS group versus 1.9% at both time points in the SES group (p=0.21). This rate remained stable up to the 2-year follow-up but did not reach significance due to the small sample. Even as early as 6 months, both types of stents significantly improved blood pressure and reduced antihypertensive medication compared to baseline (p<0.01). After 6 months, renal function worsened in 4.6% of the BMS patients and in 6.9% of the SES group. The rate of major adverse events was 23.7% for the BMS group and 26.8% for the SES at 2 years (p=0.80).. The angiographic outcome at 6 months did not show a significant difference between BMS and SES. Renal artery stenting with both stents significantly improved blood pressure. Future studies with a larger patient population and longer angiographic follow-up are warranted to determine if there is a significant benefit of drug-eluting stents in treating ostial renal artery stenosis.

Topics: Aged; Angioplasty, Balloon; Antihypertensive Agents; Blood Pressure; Cardiovascular Agents; Europe; Female; Follow-Up Studies; Humans; Hypertension; Kidney Function Tests; Male; Metals; Middle Aged; Prospective Studies; Prosthesis Design; Radiography; Recurrence; Renal Artery; Renal Artery Obstruction; Renal Insufficiency; Research Design; Sirolimus; Stents; Time Factors; Treatment Outcome; Vascular Patency

Atherosclerosis accounts for most adult cases of renal artery stenoses (RAS). Revascularization of atherosclerotic RAS is beneficial in terms of improved blood pressure control, preservation of renal function and overall decrease of cardiovascular risk, in particular in mononephric patients. Endovascular stenting has been proven superior to percutaneous transluminal angioplasty (PTA) alone in terms of initial success and restenosis rates in atherosclerotic RAS. In this case report revascularization of atherosclerotic RAS in a mononephric patient is presented and the long-term follow-up and complications of PTA and stenting are illustrated. Our case is the first report of fracture of a sirolimus-eluting stent overlapped to a previously implanted Palmaz-Schatz in the left renal artery. The mechanisms and possible remedies of this complication are discussed.

Topics: Angioplasty; Atherosclerosis; Drug-Eluting Stents; Humans; Male; Middle Aged; Renal Artery; Renal Artery Obstruction; Risk Factors; Sirolimus; Time Factors; Treatment Outcome; Ultrasonography

The objective of this study was to analyze the use of sirolimus-eluting stent (SES) placement for the treatment of renal artery in-stent restenosis (RA-ISR). The optimal treatment of RA-ISR has not been fully elucidated to date. We retrospectively analyzed consecutive patients from our institution who underwent treatment of RA-ISR with a SES from May 2004 to June 2006. Using duplex ultrasound, RA-ISR (> 60% diameter) was determined by peak systolic velocity (PSV) > 300 cm/s and renal aortic ratio (RAR) > 4.0. Renal function (creatinine) and blood pressure were measured at baseline and follow-up. SESs were implanted in 16 patients (22 renal arteries) during the study period. The study cohort was predominantly female (75%) with a mean age of 68 +/- 12 years. RA-ISR was treated with SESs with a mean diameter of 3.5 mm and mean length of 17.9 +/- 3.8 mm. The mean post-dilation balloon diameter was 4.8 +/- 0.6. The baseline renal artery PSV was 445 +/- 131 cm/s with a mean RAR of 5.0 +/- 1.6. Follow-up information was available in 21 renal arteries. During a median follow-up of 12 months (range: 9-15 months), 15 renal arteries (71.4%) developed recurrence of ISR by ultrasonographic criteria. Univariate analysis revealed that female sex was an independent predictor of recurrence of ISR after SES implantation (p < 0.05). In conclusion, placement of a SES for the treatment of ISR in renal arteries is associated with high initial technical success but significant restenosis on duplex ultrasonography at follow-up.

Topics: Aged; Aged, 80 and over; Angioplasty, Balloon; Cardiovascular Agents; Drug-Eluting Stents; Female; Hemodynamics; Humans; Hypertension, Renovascular; Kidney; Male; Middle Aged; Radiography; Recurrence; Renal Artery Obstruction; Retrospective Studies; Risk Assessment; Risk Factors; Sirolimus; Stents; Time Factors; Treatment Outcome; Ultrasonography, Doppler, Duplex

Renal artery stenosis may cause or exacerbate hypertension and renal failure. Percutaneous transluminal renal artery stent placement, increasingly the first-line therapy for ostial atherosclerotic renal artery stenosis, can be complicated by in-stent restenosis weeks to months after the procedure. There is currently no consensus for the treatment of in-stent restenosis. Sirolimus-eluting stents have been shown to be effective to treat in-stent restenosis in the coronary circulation. We report a case of sustained 24-month patency after repair of recurrent renal artery in-stent restenosis with use of a sirolimus-eluting stent.

Topics: Aged; Angioplasty, Balloon; Cardiovascular Agents; Drug-Eluting Stents; Humans; Hypertension, Renovascular; Male; Metals; Prosthesis Design; Radiography; Renal Artery Obstruction; Secondary Prevention; Sirolimus; Stents; Time Factors; Treatment Outcome; Vascular Patency

Higher rates of clinical and angiographic restenosis have been reported after coronary stenting in patients with significant chronic kidney disease (CKD). Whether drug-eluting stents (DES) can reduce long-term clinical events in CKD patients compared with bare metal stents (BMS) has not been established.. The study enrolled 104 consecutive significant CKD patients (estimated creatinine clearance <60 ml/min) treated with DES for 142 de novo coronary lesions, comprising 76 patients treated with sirolimus-eluting stents (SES) for 106 lesions and 28 patients treated with paclitaxel-eluting stents (PES) for 36 lesions. Data from these patients were compared to those from a control group comprising 50 patients treated with BMS during the preceding 1 year.. There were no differences in terms of baseline clinical characteristics except that the patients of the DES group were older, had a higher ratio of insulin treatment for diabetes mellitus, and had a more frequent history of previous percutaneous coronary intervention. The patients in the DES group had more unfavorable lesion characteristics with smaller reference vessel diameter (2.8 mm versus 3.3 mm; P<0.001) and longer lesion length (28.8 mm versus 20.5 mm; P<0.001) than those in the BMS group. Compared to BMS, DES implantation had a lower 1-year major adverse cardiac events rate (cardiac death, non-fatal myocardial infarction or target vessel revascularization) (12% versus 26%; P=0.042). There were no significant differences between the SES and PES groups in terms of clinical outcomes.. DES implantation for de novo coronary lesions in significant CKD patients reduces 1-year clinical events compared with BMS implantation.

Topics: Cardiovascular Agents; Coronary Angiography; Coronary Restenosis; Drug-Eluting Stents; Female; Humans; Kidney Failure, Chronic; Male; Middle Aged; Paclitaxel; Renal Artery Obstruction; Retrospective Studies; Risk Factors; Sirolimus; Stents; Time Factors; Treatment Outcome

To describe restenosis and clinical outcomes with drug-eluting stents (DESs) and compare them to those of bare metal stents (BMSs) in the treatment of symptomatic atherosclerotic renal artery stenosis (RAS) in the same patients.. A retrospective study was performed of all patients with RAS treated with a DES (Taxus Express 2 or Cypher). DESs were used for RASs with luminal vessel diameters of 4 mm or smaller and BMSs were used for those larger than 4 mm.. Sixteen patients (eight women; mean age, 72 years +/- 8) underwent treatment of 27 RASs for worsening renal function (n = 10) and uncontrolled hypertension (n = 6). Eighteen RASs were treated with 23 DESs (Cypher, n = 12; Taxus, n = 11) and nine were treated with BMSs. The average follow-up was 22 months +/- 10. After the procedure, the mean systolic blood pressure decreased significantly (P < .05), with no change in the mean diastolic pressure, serum creatinine, or number of antihypertensive medications. By Kaplan-Meier estimates, the 1- and 2-year patency rates for DESs were 78% and 68%, respectively; and for BMSs, the respective rates were 58% and 47% (P = NS). The average diameters of RASs were 3.4 mm +/- 0.6 in the DES group and 5.3 mm +/- 0.6 in the BMS group (P < .05). There were two technical failures (7.7%) in the DES group. There was one minor complication and a non-flow-limiting dissection.. DESs were used to treat RASs with good technical results and low restenosis rates compared with BMSs despite the smaller artery diameters in the DES group.

Topics: Aged; Aged, 80 and over; Angiography; Drug-Eluting Stents; Female; Gadolinium DTPA; Humans; Immunosuppressive Agents; Male; Middle Aged; Paclitaxel; Proportional Hazards Models; Recurrence; Renal Artery Obstruction; Retrospective Studies; Sirolimus; Stents; Treatment Outcome; Tubulin Modulators; Ultrasonography; Vascular Resistance