S. R. Ramee

Distal filter Protection during saphenous vein graft stenting: Technical and clinical correlates of efficacy

OBJECTIVES The aim of this study was to evaluate the clinical, angiographic, and technical factors related to successful stenting of diseased saphenous vein grafts (SVGs) using a novel filter-based distal protection device. BACKGROUND Protection of the distal microvasculature with a balloon occlusion and aspiration system has been shown to reduce atherothrombotic embolization and peri-procedural myocardial infarction (MI) after percutaneous coronary intervention (PCI) in SVGs. The safety, efficacy, and technical factors relating to procedural success with filter-based distal protection devices are unknown. METHODS Percutaneous coronary intervention was performed in 60 lesions in 48 patients undergoing SVG intervention with the FilterWire EX distal protection system in a phase I experience at six sites. A larger phase II study was then performed in 248 lesions in 230 SVGs at 65 U.S. centers. RESULTS Cumulative adverse events to 30 days occurred in 21.3% of patients in phase I, including a 19.1% rate of MI. Numerous anatomic, device-specific, and operator-related contributors to these adverse events were identified, resulting in significant changes to the protocol and instructions for use. Subsequently, despite similar clinical and angiographic characteristics to the phase I patients, the 30-day adverse event rate in phase II was reduced to 11.3% (p = 0.09), due primarily to a lower incidence of peri-procedural Q-wave and non-Q-wave MI. CONCLUSIONS Distal protection during SVG PCI with the FilterWire EX is associated with a low rate of peri-procedural adverse events compared to historical controls. A unique set of anatomic, technical, and operator-related issues exist with distal filters which, if ignored, may reduce their effectiveness.

One-year clinical outcomes with SAPIEN 3 transcatheter aortic valve replacement in high-risk and inoperable patients with severe aortic stenosis

Background: In the initial PARTNER trial (Placement of Aortic Transcatheter Valves) of transcatheter aortic valve replacement for high-risk (HR) and inoperable patients, mortality at 1 year was 24% in HR and 31% in inoperable patients. A recent report of the 30-day outcomes with the low-profile SAPIEN 3 transcatheter aortic valve replacement system demonstrated very low rates of adverse events, but little is known about the longer-term outcomes with this device. Methods: Between October 2013 and September 2014, 583 HR (65%) or inoperable (35%) patients were treated via the transfemoral (84%) or transapical/transaortic (16%) access route at 29 US sites. Major clinical events at 1 year were adjudicated by an independent clinical events committee, and echocardiographic results were analyzed by a core laboratory. Results: Baseline characteristics included age of 83 years, 42% female, and median Society of Thoracic Surgeons score of 8.4%. At the 1-year follow-up, survival (all-cause) was 85.6% for all patients, 87.3% in the HR subgroup, and 82.3% in the inoperable subgroup. Survival free of all-cause and cardiovascular mortality in the transfemoral patients from the HR cohort was 87.7% and 93.3%, respectively. There was no severe paravalvular leak. Moderate paravalvular leak (2.7%) was associated with an increase in mortality at 1 year, whereas mild paravalvular leak had no significant association with mortality. Symptomatic improvement as assessed by the percentage of patients in New York Heart Association class III and IV (90.1% to 7.7% at 1 year; P<0.0001) and by Kansas City Cardiomyopathy Questionnaire overall summary score (improved from 46.9 to 72.4; P<0.0001) was marked. Multivariable predictors of 1-year mortality included alternative access, Society of Thoracic Surgeons score, and disabling stroke. Conclusions: In this large, adjudicated registry of SAPIEN 3 HR and inoperable patients, the very low rates of important complications resulted in a strikingly low mortality rate at 1 year. Between 30 and 365 days, the incidence of moderate paravalvular aortic regurgitation did not increase, and no association between mild paravalvular leak and 1-year mortality was observed, although a small increase in disabling stroke occurred. These results, which likely reflect device iteration and procedural evolution, support the use of transcatheter aortic valve replacement as the preferred therapy in HR and inoperable patients with aortic stenosis. Clinical Trial Registration : URL: http://www.clinicaltrials.gov. Unique identifier: NCT01314313.

Infrapopliteal drug-eluting stents for chronic limb ischemia

Objective: We report our experience with the elective placement of below‐knee, drug‐eluting stents in patients with chronic limb ischemia. Background: Infrapopliteal percutaneous transluminal angioplasty has been associated with a lower rate of procedural success and high rate of restenosis because of the small size of the tibial vessels and the prevalence of calcified and diffuse atherosclerotic disease. Prior published data reports 3‐year patency rates below 25%. Bare metal stents have been reported in bailout situations. Drug‐eluting stents have markedly reduced restenosis compared to bare metal stents in the coronary vasculature, but there is little data supporting the use of these devices below the knee. Methods: Elective placement of drug‐eluting stents in infrapopliteal lesions was performed on 10 patients with severe (≥Fontaine Stage IIb) claudication (n = 1) or limb‐threatening ischemia (n = 9) (rest pain, nonhealing ulcers and gangrene). Results: A total of 17 drug‐eluting stents were electively placed in 12 below‐knee arteries in 10 patients, resulting in an average of 1.7 ± 0.7 stents per patient. The mean lesion length was 24.8 ± 10.9 mm, the mean total stent length was 38.3 ± 19.1 mm, and the mean nominal stent diameter was 2.8 ± 0.3 mm. One patient required target vessel revascularization (TVR) at 3 weeks because of stent thrombosis. TVR was 10% at 12.4 ± 6.5 months of follow‐up. Clinically driven angiography in three different patients was performed at 4, 15, and 16 months and confirmed drug‐eluting stent patency in each case. Conclusions: The use of below‐knee drug‐eluting stents is feasible and appears to be safe in our small series of complex infrapopliteal lesions causing chronic limb ischemia. The occurrence of a single case of stent thrombosis warrants continued observation in this cohort. Prospective clinical trials will be necessary to confirm the benefits and justify the costs of this strategy for treating patients with infrapopliteal culprit lesions and chronic limb ischemia.

Optical properties of fiber optic surgical tips.

The optical emission pattern of experimental sphere-tipped fibers and an assortment of shapes of sapphire-tipped fibers has been measured. The emission patterns were recorded in both air and water. These patterns show that cone and wedge shaped tips unexpectedly have focusing properties. The observed patterns help give an understanding of the results that the tips produce on tissues. The optical analysis suggests ways of improving tip designs.

Three-year follow-up after intravascular γ-radiation for in-stent restenosis in saphenous vein grafts: Radiation Therapy for Vein Graft ISR

The Washington Radiation for In‐Stent Restenosis Trial in Saphenous Vein Grafts (SVG WRIST) demonstrated safety and efficacy of intravascular radiation therapy (IRT) for the treatment of in‐stent restenosis (ISR) in SVG at 12 months. In this study, we aimed to examine whether the safety and efficacy of IRT is durable up to 36 months. One hundred twenty patients with diffuse ISR in SVG underwent balloon angioplasty, laser or atherectomy ablation, and/or additional stenting. After successful intervention, patients were randomly assigned in a double‐blind fashion to intravascular treatment with a ribbon containing either iridium (Ir)‐192 (n = 60) or nonradioactive seeds (n = 60). The prescribed dose at 2 mm from the source was either 14 or 15 Gy in vessels 2.5–4.0 mm or 18 Gy in vessels > 4.0 mm in diameter. At 36 months, target lesion revascularization (TLR; 43% vs. 66%; P = 0.02) and target lesion revascularization‐major adverse cardiac event (TLR‐MACE; 49% vs. 71%; P = 0.02) rates continued to be lower in the IRT group, but both target vessel revascularization (TVR; 59% vs. 71%; P = 0.17) and TVR‐MACE (63% vs. 77%; P = 0.11) rates were not. In SVG WRIST, patients with ISR treated with IRT had a marked reduction in the need for repeat TLR at 36 months, with sustained clinical benefit at 3 years despite late recurrences, which were more pronounced in the radiation group.