Nicolas W. Shammas

Evaluation Of Diabetic Patients For Renal And Pancreas Transplantation: Noninvasive Screening for Coronary Artery Disease Using Radionuclide Methods

Pharmacologic stress thallium scintigraphy is commonly performed in the risk assessment of diabetic patients with nephropathy before kidney and/or pancreas transplantation; however, controversy exists regarding the tests accuracy in detecting coronary artery disease. Our purpose was to compare pharmacologic stress thallium scintigraphy and also exercise radionuclide ventriculography with coronary angiography in diabetic patients undergoing evaluation for transplantation. In addition, we also determined the association of the test results with outcome after transplantation. The medical records of 47 patients (mean age, 37+/-9 years) without clinical evidence of coronary artery disease were reviewed. Forty-one patients had pharmacologic stress thallium scintigraphy performed during their evaluation. Sensitivity was 62% and specificity was 76% for detecting > or = 75% coronary artery stenosis (sensitivity was 53% and specificity was 73% for > or = 50% stenosis). Thirty-five patients had exercise radionuclide ventriculography performed. Sensitivity was 50% and specificity was 67% for detecting > or = 75% coronary artery stenosis (sensitivity was 44% and specificity was 63% for > or = 50% stenosis). Thirty patients had both pharmacologic stress thallium scintigraphy and exercise radionuclide ventriculography performed; when either test was abnormal, sensitivity in the detection of > or = 50% or > or = 75% stenosis tended to increase compared with pharmacologic stress thallium scintigraphy alone (0.05<P<0.10), whereas specificity decreased (P<0.01). The incidence of adverse cardiac outcomes was identical for patients with abnormal thallium scintigrams and undergoing transplantation (2/11) compared with patients with normal scintigrams and undergoing transplantation (4/22). We conclude that: (1) pharmacologic stress thallium scintigraphy and exercise radionuclide ventriculography are suboptimal screening tests for coronary artery disease in diabetic patients awaiting kidney and/or pancreas transplantation; (2) using the two radionuclide tests in combination results in a decrease in specificity; and (3) patients with abnormal thallium scintigrams can receive transplants with outcomes similar to those for patients with normal thallium scintigrams.

Pilot Trial of Cryoplasty or Conventional Balloon Post-Dilation of Nitinol Stents for Revascularization of Peripheral Arterial Segments: The COBRA Trial

OBJECTIVES The purpose of this study is to compare post-dilation strategies of nitinol self-expanding stents implanted in the superficial femoral artery of diabetic patients with peripheral arterial disease. BACKGROUND Endovascular treatment of superficial femoral artery disease with nitinol self-expanding stents is associated with high rates of in-stent restenosis in patients with diabetes mellitus. METHODS We conducted a prospective, multicenter, randomized, controlled clinical trial of diabetic patients to investigate whether post-dilation of superficial femoral artery nitinol self-expanding stents using a cryoplasty balloon reduces restenosis compared to a conventional balloon. Inclusion criteria included diabetes mellitus, symptomatic peripheral arterial disease, and superficial femoral artery lesions requiring implantation of stents>5 mm in diameter and >60 mm in length. Primary endpoint was binary restenosis at 12 months, defined as ≥2.5-fold increase in peak systolic velocity by duplex ultrasonography. RESULTS Seventy-four patients, with 90 stented superficial femoral artery lesions, were randomly assigned to post-dilation using cryoplasty (n=45 lesions) or conventional balloons (n=45 lesions). Mean lesion length was 148±98 mm, mean stented length was 190±116 mm, mean stent diameter was 6.1±0.4 mm, and 50% of the lesions were total occlusions. Post-dilation balloon diameters were 5.23±0.51 mm versus 5.51±0.72 mm in the cryoplasty and conventional balloon angioplasty groups, respectively (p=0.02). At 12 months, binary restenosis was significantly lower in the cryoplasty group (29.3% vs. 55.8%, p=0.01; odds ratio: 0.36, 95% confidence interval: 0.15 to 0.89). CONCLUSIONS Among diabetic patients undergoing implantation of nitinol self-expanding stents in the superficial femoral artery, post-dilation with cryoplasty balloon reduced binary restenosis compared to conventional balloon angioplasty. (Study Comparing Two Methods of Expanding Stents Placed in Legs of Diabetics With Peripheral Vascular Disease [COBRA]; NCT00827853).

JetStream Rotational and Aspiration Atherectomy in Treating In-Stent Restenosis of the Femoropopliteal Arteries: Results of the JETSTREAM-ISR Feasibility Study.

Purpose: To evaluate the outcomes and stent-device interaction of the JetStream atherectomy device in the treatment of in-stent restenosis (ISR) of the femoropopliteal segment. Methods: The JetStream XC atherectomy device, a rotational cutter with aspiration capacity, was evaluated in a prospective cohort of 29 patients (mean age 69.9±11.7 years; 11 men) with femoropopliteal ISR in 32 limbs (ClinicalTrials.gov identifier NCT01722877). Lesion length was 17.4±13.1 cm. The primary effectiveness outcome was acute success (≤30% residual narrowing with no serious adverse events). The primary safety endpoint was major adverse events. Secondary endpoints included clinically driven target lesion revascularization (TLR) at 6 months and 1 year and loss of stent integrity as assessed by an angiographic core laboratory. Results: Treated length was 19.5±12.9 cm. Acute success was obtained in 29/32 (91%) limbs. Acute device success (<50% residual narrowing after atherectomy alone) was 76% (22/29). Adjunctive balloon angioplasty was performed in all cases at a mean pressure of 11.6±3.3 atm. Embolic filter protection was used in 16 (50%) of 32 limbs. Macrodebris was noted in 2 (12%) of 16 filters. Distal embolization requiring treatment occurred in 3/32 (9.4%) limbs (2 with no filter). Other non-procedure-related adverse events were 1 (3%) death (nonvascular) and 1 (3%) case of major bleeding. There were no new stent fractures or deformities (n=24) postatherectomy. Follow-up was completed on 27 patients (29 limbs) at 6 and 12 months. TLR at these time points occurred in 4/29 (14%) and 12/29 (41%) patients. Patency (duplex-derived peak systolic velocity ratio <2.4) was 72% at 6 months. Conclusion: JetStream atherectomy using the XC device has favorable acute results in treating femoropopliteal ISR with high procedure success, no device-stent interaction, and favorably low TLR rates. A multicenter trial is needed to confirm these results.

Femoropopliteal Artery Stent Thrombosis Report From the Excellence in Peripheral Artery Disease Registry

Background—There are limited data on femoropopliteal artery stent thrombosis (ST), which is a serious adverse outcome of peripheral artery interventions. Methods and Results—Index procedures resulting in femoropopliteal ST were compared with stent procedures without subsequent ST in the Excellence in Peripheral Artery Disease registry. The study data had a total of 724 cases of stent procedures and 604 unique patients. Femoropopliteal ST occurred in 26 of 604 patients (4.3%) over a median follow-up of 6 months post procedure. ST was more likely to occur in men (96.3% versus 82.2%; P=0.026) and to have an initial intervention for chronic total occlusions (88.5% versus 64.0%; P=0.01). There was no significant difference in ST between drug-coated and bare-metal stents (4.4% versus 3.4%; P=0.55), but the rate of ST was significantly higher with self-expanding covered stent grafts compared with bare-metal stents (10.6% versus 3.4%; P=0.02). ST was significantly associated with an increased risk of 12-month major adverse limb events (hazard ratio, 4.99; 95% confidence interval, 2.31–10.77; P<0.001) compared with no ST. On multivariate analysis, treatment of chronic total occlusion lesions (odds ratio, 3.46; 95% confidence interval, 0.98–12.20; P=0.05) and in-stent restenosis lesions (odds ratio, 5.30; 95% confidence interval, 1.83–15.32; P=0.002) were independently associated with an increased risk of ST. Conclusions—In a multicenter peripheral interventional registry, femoropopliteal ST occurred in 4.3% of patients who underwent stent procedures, and it was associated with treatment of chronic total occlusions and in-stent restenosis lesions, and had higher 12-month major adverse limb events. Clinical Trial Registration—URL: http://www.clinicaltrials.gov. Unique identifier: NCT01904851.

Comparative assessment of guidewire and microcatheter vs a crossing device-based strategy to traverse infrainguinal peripheral artery chronic total occlusions

Purpose: To compare success rates of a guidewire and microcatheter strategy vs the use of specialized crossing devices to traverse infrainguinal peripheral artery chronic total occlusions (CTOs). Methods: For this analysis, data on 438 consecutive infrainguinal CTO interventions in 438 patients (mean age 63.2 years; 402 men) performed between August 2006 and May 2014 were extracted from the multicenter Excellence in Peripheral Artery Disease (XLPAD) database (ClinicalTrials.gov; identifier NCT01904851). Primary technical success constituted placement of a guidewire in the true lumen, past the distal CTO cap, with the initial crossing strategy. Results: A wire-catheter strategy was used in 295 (67.4%) and a specialized CTO crossing device in 143 (32.6%) patients (p<0.001). Primary crossing technical success was higher with CTO devices (72.1% vs 51.9%, p<0.001). The primary wire-catheter arm used significantly more secondary CTO devices (28.1% vs 17.5%) and/or provisional re-entry devices (26.7% vs 4.9%) compared with the primary CTO device arm (both p<0.001). Secondary crossing technical success (defined as crossing with an alternate strategy: 67.5% vs 71.4%, p=1.000), provisional crossing technical success (defined as use of a re-entry device: 84.2% vs 87.5%, p=0.768), and procedure success (93.6% vs 90.9%, p=0.332) were similar between the wire-catheter and CTO device strategies, respectively. No differences were observed in periprocedural complications or 30-day adverse events; however, at 12 months, there was a significantly higher surgical revascularization rate in the primary wire-catheter arm (8.8% vs 2.8%, p=0.025). Conclusion: Infrainguinal peripheral artery CTO crossing is frequently attempted with a wire-catheter technique; however, an initial CTO crossing device approach is associated with higher primary technical success. Overall procedure success is similar with both strategies.

One-year outcomes of the U.S. and Japanese regulatory trial of the Misago stent for treatment of superficial femoral artery disease (OSPREY study)

OBJECTIVE The purpose of this study was to assess the safety and efficacy of the Misago stent (Terumo Corp, Tokyo, Japan) in occlusive and stenotic superficial femoral artery (SFA) disease. METHODS The safety and efficacy of the Misago SFA stent were evaluated prospectively in this initial collaboration trial between Japan and the United States. Because this trial enrolled patients mainly from Japan and the United States and because there is a question as to whether a race difference exists in SFA stent performance, the race difference on outcome was also analyzed. In addition, results were compared with a prior SFA stent trial. RESULTS The Misago stent was implanted in 261 subjects with TransAtlantic Inter-Society Consensus (TASC) type A and type B SFA lesions (201 subjects in the United States, 50 in Japan, 9 in Taiwan, 1 in South Korea). The mean age of the patients was 69.3 ± 10.0 years, and the mean lesion length was 83.8 ± 41.3 mm. The overall 12-month primary patency rate and clinically driven target lesion revascularization were 82.9% and 13.0%, respectively. Regional differences within the Occlusive/Stenotic Peripheral Artery Revascularization Study (OSPREY) and outcomes between U.S. and Asian patients were similar, including primary patency (82.9% vs 83.0%; P = .889), clinically driven target lesion revascularization (13.4% vs 11.7%; P = .829), stent fracture rate (1.3% vs 0.0%; P = 1.000), and stent thrombosis rate (0.5% vs 0.0%; P = 1.000). CONCLUSIONS OSPREY 12-month data showed satisfactory outcome of the Misago stent for the treatment of TASC type A and type B SFA lesions and appears to be comparable to recent stent trials. In addition, the lack of difference in outcome among races supports the value of international trials.

Current Role of Atherectomy for Treatment of Femoropopliteal and Infrapopliteal Disease

Atherectomy improves the acute procedural success of a procedure whether treating de novo or restenotic (including in-stent) disease. Intermediate follow-up results seem to be in favor of atherectomy in delaying and reducing the need for repeat revascularization in patients with femoropopliteal in-stent restenosis. Recent data suggest that avoiding cutting into the external elastic lamina is an important factor in reducing restenosis. The interplay between directional atherectomy and drug-coated balloons is unclear.

Adjunctive stent use during endovascular intervention to the femoropopliteal artery with drug coated balloons: Insights from the XLPAD registry

With growing use of drug-coated balloons (DCB) for femoropopliteal (FP) artery interventions, there is limited information on rates of real-world adjunctive stent use and its association with short and long-term outcomes. We report on 225 DCB treated FP lesions in 224 patients from the Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851) between 2014 and 2016. Cochran–Mantel–Haenszel and Wilcoxon rank sum statistics were used to compare stented (planned or ‘bail-out’) versus non-stented DCB treated lesions. Stents were implanted in 31% of FP DCB interventions. Among the 70 stents implanted, 46% were for ‘bail-out’ indications and 54% were planned. Lesions treated with stents were longer (mean 150 mm vs 100 mm; p < 0.001) and less likely to be in-stent restenosis lesions (10% vs 28%; p=0.003). Stenting was significantly more frequent in complex FP lesions, including chronic total occlusions (66% vs 34%; p < 0.001). For bail-out stenting, interwoven nitinol stents were the most common type (50%) followed by drug-eluting stents (34%) and bare-metal stents (22%). There were no differences in peri-procedural complication rates or 12-month target limb revascularization rates (18.6% vs 11.6%; p=0.162) or 12-month amputation rates (11.4% vs 11%; p=0.92) between lesions where adjunctive stenting was used versus lesions without adjunctive stenting, respectively. In conclusion, in a contemporary ‘real-world’ adjudicated multicenter US registry, adjunctive stenting was necessary in nearly a third of the lesions, primarily for the treatment of more complex FP lesions, with similar short and intermediate-term clinical outcomes compared with non-stented lesions. ClinicalTrials.gov Identifier: NCT01904851

Long-term outcomes with Jetstream atherectomy with or without drug coated balloons in treating femoropopliteal arteries: A single center experience (JET-SCE)

BACKGROUND The long-term outcome of Jetstream atherectomy (JA) with or without adjunctive drug coated balloons (DCB) in a real-world setting remains unknown. We report 16-month target lesion revascularization (TLR) rates on patients treated for femoropopliteal (FP) artery disease with JA in a single center by one operator. METHODS From 1/1/12 to 8/24/16 a total of 311 procedures were performed with atherectomy by a single operator at a single center. Of these procedures, 75 met inclusion and exclusion criteria. This report evaluates the outcomes of these 75 patients treated at index and who were followed up to 16 months. The primary endpoint of the study was clinically driven TLR. Patients were stratified by the use of DCB (vs angioplasty (PTA)) post-JA. TLR was calculated by excluding bailout stenting as TLR. Survival analysis for TLR over time was plotted. RESULTS 75 patients (49.3% male, mean age 68.0 years, 54.7% diabetes) with de novo or restenotic FP lesions whose symptoms were classified as Rutherford category I-V were enrolled. Adjunctive PTA was performed on 50 patients (26 de novo, 13 in-stent restenosis, 3 non-stent restenosis, 8 mixed lesions) and adjunctive DCB (LUTONIX® 24, IN.PACT® 1) on 25 patients (21 de novo, 1 in-stent restenosis, 2 non-stent restenosis, 1 mixed lesion) (p = 0.0249). There was no difference in the median treated length between the adjunctive PTA (15 cm) and DCB (10 cm) groups (p = 0.0530). The estimated freedom from TLR (fTLR) was significantly higher with atherectomy and adjunctive DCB compared to atherectomy with adjunctive PTA at 12 months (94.7% vs 68.0%, p = 0.002) and 16 months (94.4% vs 54%; p = 0.002). CONCLUSIONS In a single center cohort of JA reflecting real-world practice, JA with DCB had a superior TLR rate up to 16-month follow-up when compared to JA with PTA in treating all comers FP arterial disease.

COMPARATIVE ASSESSMENT OF SUBINTIMAL VERSUS INTRALUMINAL CROSSING OF INFRAINGUINAL CHRONIC TOTAL OCCLUSION LESIONS

Background: Subintimal (SI) and intraluminal (IL) crossing of infrainguinal chronic total occlusion (CTO) lesions is frequently used, however, comparative outcomes are lacking. This study compares postprocedural complications and outcomes between these two techniques. Methods: We selected 1,335 CTO