Craig M. Walker

Long-term angiographic and clinical outcome after implantation of a ballon-expandable stent in the native coronary circulation☆

Objectives. The purpose of this study was to examine the long-term clinical and angiographic outcome after coronary implantation. Background. Previous reports haw shown a discordance between the excellent initial angiographic results and subsequent adverse clinical events after coronary artery stenting. Methods. Single Palmaz-Schatz stents were electively implanted in the native coronary arteries of 300 consecutive patients. Angiograms were obtained at baseline, after balloon angioplasty, after stent implantation and at 6 months after implantation. Films were analyzed by a panel of engiographers utilizing en automated edge detection program, Clinical events, including death, myocardial infarction, coronary bypass surgery and repeat angioplasty, were recorded for 1 year. Results. Although there were no acute in-laboratory vessel closures, stent thrombosis occurred in 14 patients (4.7%) at a mean ±SD of 5 ± 3 days after implantation. Two hundred fifty-eight (90%) of 286 eligible patients had follow-up angiography at 6.1 ± 2.2 months after stent implantation. Minimal lumen diameter increased from 0.80 ± 039 mm at baseline to 1.65 +- 0.51 mm after angioplasty and further increased to 2.55 ± 0.49 mm after stent placement (p = 0.0001). At follow-up there was a 0.85-mm late loss in lumen diameter, with a final minimal lumen diameter at 6 months of 1.70 ± 0.71 mm. Restenosis, defined as ≥ 50% diameter stenosis at follow-up, occurred in 14% of patients with previously untreated lesions and in 39% of patients with previous angioplasty (p < 0.001). Clinical events after 1 year for the entire group of 300 patients included death in 0.7%, myocardial infarction in 3.7%, bypass grafting in 8% and repeat angioplasty in 13%. Freedom from any adverse clinical event was 80% for all treated patients and 87% for those with previously untreated lesions. Conclusions. Elective use of this balloon-expandable stent in the native coronary circulation is associated with a low restenosis rate by quantitative angiography in previously untreated lesions and a favorable clinical outcome with an excellent event-free survival rate at 1 year.

Immediate results and late outcomes after stent implantation in saphenous vein graft lesions: The multicenter U.S. Palmaz-Schatz stent experience

OBJECTIVES This study reports the multicenter registry experience evaluating the safety and efficacy of the Palmaz-Schatz stent in the treatment of saphenous vein graft disease. BACKGROUND Saphenous vein graft angioplasty is associated with frequent periprocedural complications and a high frequency of restenosis. Stent implantation has been shown to reduce restenosis, with improved long-term outcomes in the treatment of native coronary artery disease. Preliminary experience with stent placement in the treatment of saphenous vein graft lesions has been favorable. METHODS Twenty U.S. investigator sites enrolled a total of 589 symptomatic patients (624 lesions) for treatment of focal vein graft stenoses between January 1990 and April 1992. Follow-up angiography was performed at 6 months, and the clinical course of all study patients was prospectively collected at regular intervals for up to 12 months. RESULTS Stent delivery was successful in 98.8% of cases, and the procedural success rate was 97.1%. The lesion diameter stenosis decreased from 82 +/- 12% (mean +/- SD) before to 6.6 +/- 10.2% after treatment. Major in-hospital complications occurred in 17 patients (2.9%); stent thrombosis was found in 8 (1.4%); and major vascular or bleeding complications were noted in 83 (14.3%). Six-month angiographic follow-up revealed an overall restenosis rate (> or = 50% diameter stenosis) of 29.7%. Multivariate logistic regression analysis indicated that 1) restenotic lesions, 2) smaller reference vessel size, 3) history of diabetes mellitus, and 4) higher percent poststent diameter stenosis were independent predictors of restenosis. The 12-month actuarial event-free survival was 76.3%. CONCLUSIONS Stent implantation in patients with focal saphenous vein graft lesions can be achieved with a high rate of procedural success, acceptable major complications, reduced angiographic restenosis and favorable late clinical outcome compared with historical balloon angioplasty control series. The rigorous anticoagulation regimen after stent placement results in more frequent vascular and other bleeding complications. Future randomized studies comparing standard balloon angioplasty with stent implantation are warranted to properly assess the full impact of stent placement in the treatment of saphenous vein graft lesions.

Multicenter Trial of the Wallstent in the Iliac and Femoral Arteries

PURPOSE To report the results of the FDA phase II, multicenter trial of the Wallstent in the iliac and femoral arteries. PATIENTS AND METHODS Two hundred twenty-five patients entered the trial. Stents were placed in the iliac system in 140 patients and in the femoral system in 90 (five patients required both iliac and femoral stents). Clinical patency was measured over 2 years by means of life-table analysis with use of clinical and hemodynamic data and the Rutherford scale. Angiographic patency was measured at 6 months. RESULTS In the iliac system the primary clinical patency was 81% at 1 year and was 71% at 2 years. The secondary clinical patency was 91% and 86%, respectively. The 6-month angiographic patency was 93%. In the femoral system the primary clinical patency was 61% at 1 year and 49% at 2 years. The secondary patency was 84% and 72%, respectively. The 6-month angiographic patency was 80%. CONCLUSIONS The results are similar to those with the Palmaz stent in the iliac system and with angioplasty alone in the iliac and femoral systems.

Fate of lesion-related side branches after coronary artery stenting

OBJECTIVES The aim of this study was to assess the immediate and long-term patency of lesion-associated side branches after coronary artery stenting. BACKGROUND The possible adverse effects related to implantation of coronary stents are not completely known. An important potential complication of stenting is side branch occlusion due to mechanical obstruction or thrombosis. METHODS Serial coronary angiography was performed in 153 patients (167 lesions) at baseline, after conventional balloon angioplasty, immediately after Palmaz-Schatz stent placement and at 6 months. The patency of side branches, where present, was analyzed at each of these points. RESULTS Of 167 lesions stented, 57 stent placements spanned 66 side branches with a diameter > or = 1 mm. Twenty-seven (41%) of these side branches had > or = 50% ostial stenosis before standard balloon angioplasty. Six side branches became occluded after standard balloon angioplasty and remained occluded after stenting. Of the 60 side branches patent after conventional angioplasty, 57 (95%) remained patent immediately after stenting. All three side branches that became occluded after stenting had > or = 50% ostial stenosis at baseline. All 60 side branches, including the 3 initially occluded after stenting, were patent at 6-month follow-up. CONCLUSIONS These findings demonstrate that 1) acute side branch occlusion due to coronary stenting occurs infrequently; 2) when side branch occlusion occurs, it is associated with intrinsic ostial disease; and 3) the patency of side branch ostia is well maintained at long-term follow-up.

Midterm Outcomes from the TALON Registry: Treating Peripherals with SilverHawk: Outcomes Collection

Purpose: To determine midterm clinical outcomes among patients with lower extremity peripheral arterial disease who underwent revascularization with catheter-based plaque excision (PE). Methods: Between August 2003 and February 2005, 19 institutions participating in the observational, nonrandomized, multicenter TALON registry enrolled 601 consecutive patients (353 men; mean age 70±11, range 36–98) with 1258 symptomatic lower extremity atherosclerotic lesions (748 limbs) treated by plaque excision with the SilverHawk catheter. Approximately 50% of the patients had diabetes, and nearly one third of the procedures were indicated for Rutherford ischemia category ≥4. Mean lesion lengths above and below the knee, respectively, were 62.5±68.5 mm (interquartile range [IQR], 20.0–80.0) and 33.4±42.7 mm (IQR 15.0–37.5). The primary endpoints of the study were target lesion revascularization (TLR) at 6 and 12 months. Results: The device achieved ≤50% residual diameter stenosis in 94.7% of lesions; procedural success was 97.6%. Nearly half (41.9%) of the procedures involved PE of ≥2 lesions. Nearly three quarters (73.3%) of the lesions did not require adjunctive therapy, and stent placement following PE occurred in only 6.3% of lesions. The 6- and 12-month rates of survival free of TLR were 90% and 80%, respectively. Rates of TLR were similar among patients with diabetes (11%) and without diabetes (9%). In the multivariate analysis, significant predictors of TLR at 6 months were a history of MI or coronary revascularization (HR 5.49, 95% CI 1.87 to 16.10, p=0.0008), multiple (≥2) lesions (HR 1.37, 95% CI 1.11 to 1.70, p=0.0019), and increasing Rutherford category (HR 1.84, 95% CI 1.28 to 2.65, p=0.0003). Lesion length >50 mm was associated with a 2.9-fold increased risk for TLR (HR 2.88, 95% CI 1.18 to 7.01, p=0.012); lesion length >100 mm was associated with a 3.3-fold increase in TLR (HR 3.32, 95% CI 1.15 to 9.56, p=0.016). Conclusion: In patients undergoing revascularization for lower extremity atherosclerotic disease, catheter-based PE achieves favorable procedural success and avoids the need for repeat revascularization at midterm follow-up. These findings support PE as a primary endovascular therapy for patients undergoing lower extremity arterial revascularization.

Procedural and Clinical Outcomes with Catheter-Based Plaque Excision in Critical Limb Ischemia

Purpose: To examine the safety and efficacy of catheter-based plaque excision as an alternative therapy to surgery, conventional angioplasty, and/or stenting in high-risk patients with critical limb ischemia (CLI). Methods: Between August 2003 and August 2004, a prospective evaluation was conducted of consecutive patients with CLI (Rutherford category ≥5) who were treated with endovascular plaque excision at 7 institutions. This study enrolled 69 patients (37 women; mean age 70±12 years, range 43–93) with CLI involving 76 limbs. Clinical outcomes were prospectively followed for 6 months. The primary endpoint was major adverse events (death, myocardial infarction, unplanned amputation, or repeat target vessel revascularization) at 30 days. Visible healing of ulcerated tissue, avoidance of any amputation, and performance of less extensive amputation than initially planned were also assessed. Results: Procedural success was achieved in 99% of cases. Major adverse events occurred in 1% of patients at 30 days and 23% at 6 months. The target lesion revascularization rate was 4%, and there were no unplanned limb amputations. Amputation was less extensive than initially planned or avoided altogether in 92% of patients at 30 days and 82% at 6 months. Conclusion: Catheter-based plaque excision is a safe and effective revascularization method for patients with CLI. These findings support further study of this modality as a singular or adjunctive endovascular therapy for limb salvage in CLI.

Novel simultaneous combination chemical thrombolysis/rheolytic thrombectomy therapy for acute critical limb ischemia: The power‐pulse spray technique

The novel power‐pulse spray (P‐PS) technique maximizes and combines the advantages and minimizes the disadvantages of both chemical thrombolysis (CT) and rheolytic thrombectomy (RT). Forty‐nine consecutive patients with iliofemoral thrombotic occlusion were treated via P‐PS technique. Using a 6 Fr RT catheter, saline prime was exchanged for thrombolytic solution [group 1, 10–20 mg tenecteplase (TNK)/50 cc saline, n = 25; group 2, 1,000,000 urokinase (UK)/50 cc saline, n = 24]. The outflow port was closed, then the catheter was advanced at 1 mm increments while pulsing lytic agent. After 30‐min lysis time, RT and definitive treatment of the underlying stenosis were performed. Procedure success was 23/25 (92%) and 22/24 (91.6%) for group 1 and 2, respectively. The mean total procedure time was 72 and 75 min in group 1 and 2, respectively. Thirty‐day limb salvage was 91% in both groups. There were no major surgical complications. The P‐PS technique is safe and effective using either UK or TNK, offering several potential advantages over monotherapy, including more rapid revascularization, decreases systemic lytic exposure and bleeding complications while facilitating both CT and RT capacity and efficacy. Catheter Cardiovasc Interv 2004;63:512–522.

Randomized Controlled Study of Excimer Laser Atherectomy for Treatment of Femoropopliteal In-Stent Restenosis: Initial Results From the EXCITE ISR Trial (EXCImer Laser Randomized Controlled Study for Treatment of FemoropopliTEal In-Stent Restenosis)

OBJECTIVES The purpose of this study was to evaluate the safety and efficacy of excimer laser atherectomy (ELA) with adjunctive percutaneous transluminal angioplasty (PTA) versus PTA alone for treating patients with chronic peripheral artery disease with femoropopliteal bare nitinol in-stent restenosis (ISR). BACKGROUND Femoropopliteal stenting has shown superiority to PTA for lifestyle-limiting claudication and critical limb ischemia, although treating post-stenting artery reobstruction, or ISR, remains challenging. METHODS The multicenter, prospective, randomized, controlled EXCITE ISR (EXCImer Laser Randomized Controlled Study for Treatment of FemoropopliTEal In-Stent Restenosis) trial was conducted across 40 U.S. centers. Patients with Rutherford Class 1 to 4 and lesions of target lesion length ≥4 cm, vessel diameter 5 to 7 mm were enrolled and randomly divided into ELA + PTA and PTA groups by a 2:1 ratio. The primary efficacy endpoint was target lesion revascularization (TLR) at 6-month follow up. The primary safety endpoint was major adverse event (death, amputation, or TLR) at 30 days post-procedure. RESULTS Study enrollment was stopped at 250 patients due to early efficacy demonstrated at a prospectively-specified interim analysis. A total of 169 ELA + PTA subjects (62.7% male; mean age 68.5 ± 9.8 years) and 81 PTA patients (61.7% male; mean age 67.8 ± 10.3 years) were enrolled. Mean lesion length was 19.6 ± 12.0 cm versus 19.3 ± 11.9 cm, and 30.5% versus 36.8% of patients exhibited total occlusion. ELA + PTA subjects demonstrated superior procedural success (93.5% vs. 82.7%; p = 0.01) with significantly fewer procedural complications. ELA + PTA and PTA subject 6-month freedom from TLR was 73.5% versus 51.8% (p < 0.005), and 30-day major adverse event rates were 5.8% versus 20.5% (p < 0.001), respectively. ELA + PTA was associated with a 52% reduction in TLR (hazard ratio: 0.48; 95% confidence interval: 0.31 to 0.74). CONCLUSIONS The EXCITE ISR trial is the first large, prospective, randomized study to demonstrate superiority of ELA + PTA versus PTA alone for treating femoropopliteal ISR. (Randomized Study of Laser and Balloon Angioplasty Versus Balloon Angioplasty to Treat Peripheral In-stent Restenosis [EXCITE ISR]; NCT01330628).

Wallgraft Endoprosthesis for the Percutaneous Treatment of Femoral and Popliteal Artery Aneurysms

Purpose: To evaluate the safety and efficacy of the Wallgraft Endoprosthesis for the treatment of femoropopliteal artery aneurysms. Methods: From October 1997 to April 2000, 17 patients (13 men; mean age 73.5 ± 7.1 years) with 7 femoral and 13 popliteal artery aneurysms underwent percutaneous aneurysm exclusion using the Wallgraft Endoprosthesis as part of a larger clinical trial. The mean aneurysm diameters were 37.6 ± 12.9 mm and 22.3 ± 8.7 mm, respectively. Results: Acute procedural success was 100% for femoral aneurysms and 92.3% (12/13) in the popliteal artery owing to one endoleak that resolved after 1 month. There were no complications, and the mean length of stay was 2.2 ± 3.8 days. Six-month and 1-year aneurysm exclusion rates were 100% for both locations, but 4 (31%) popliteal stent-grafts thrombosed in follow-up. Three were recanalized, but the fourth underwent bypass grafting after 3 thrombotic episodes. The 1-year primary and secondary patency rates were both 100% for the femoral aneurysms and 69% and 92%, respectively, for popliteal repairs. No procedure or device-related deaths occurred. Conclusions: Treatment of aneurysms in the femoropopliteal segment appears to be safe and effective with the Wallgraft Endoprosthesis, although longer follow-up in a larger patient group will be needed to determine this techniques potential versus surgical repair.

Intraoperative innominate and common carotid intervention combined with carotid endarterectomy: a "true" endovascular surgical approach.

Purpose: To report the technique of carotid endarterectomy (CEA) combined with retrograde balloon angioplasty and stenting of proximal “tandem” lesions in the supra-aortic trunk. Technique: Intraoperative techniques in 34 patients with 23 left common carotid artery (CCA) and 11 innominate artery lesions included general anesthesia, low-dose dextran, prosthetic patching, selective shunting, 8-F sheath entry into the native CCA before the CEA, manual CCA sizing, and balloon-expandable stent placement after predilation. The technique has a high procedural success rate (97%) and appears durable. Over a mean 34-month follow-up, 2 >70% ostial CCA restenoses were found at 24 months. Conclusions: Intraoperative innominate or left CCA balloon angioplasty/stenting combined with carotid endarterectomy is safe, effective, and durable.