A Prospective, Single-Arm, Multicenter Trial of Ultrasound-Facilitated, Catheter-Directed, Low-Dose Fibrinolysis for Acute Massive and Submassive Pulmonary Embolism: The SEATTLE II Study.

OBJECTIVES: This study conducted a prospective, single-arm, multicenter trial to evaluate the safety and efficacy of ultrasound-facilitated, catheter-directed, low-dose fibrinolysis, using the EkoSonic Endovascular System (EKOS, Bothell, Washington). BACKGROUND: Systemic fibrinolysis for acute pulmonary embolism (PE) reduces cardiovascular collapse but causes hemorrhagic stroke at a rate exceeding 2%. METHODS: Eligible patients had a proximal PE and a right ventricular (RV)-to-left ventricular (LV) diameter ratio ≥0.9 on chest computed tomography (CT). We included 150 patients with acute massive (n = 31) or submassive (n = 119) PE. We used 24 mg of tissue-plasminogen activator (t-PA) administered either as 1 mg/h for 24 h with a unilateral catheter or 1 mg/h/catheter for 12 h with bilateral catheters. The primary safety outcome was major bleeding within 72 h of procedure initiation. The primary efficacy outcome was the change in the chest CT-measured RV/LV diameter ratio within 48 h of procedure initiation. RESULTS: Mean RV/LV diameter ratio decreased from baseline to 48 h post-procedure (1.55 vs. 1.13; mean difference, -0.42; p < 0.0001). Mean pulmonary artery systolic pressure (51.4 mm Hg vs. 36.9 mm Hg; p < 0.0001) and modified Miller Index score (22.5 vs. 15.8; p < 0.0001) also decreased post-procedure. One GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries)-defined severe bleed (groin hematoma with transient hypotension) and 16 GUSTO-defined moderate bleeding events occurred in 15 patients (10%). No patient experienced intracranial hemorrhage. CONCLUSIONS: Ultrasound-facilitated, catheter-directed, low-dose fibrinolysis decreased RV dilation, reduced pulmonary hypertension, decreased anatomic thrombus burden, and minimized intracranial hemorrhage in patients with acute massive and submassive PE. (A Prospective, Single-arm, Multi-center Trial of EkoSonic® Endovascular System and Activase for Treatment of Acute Pulmonary Embolism (PE) [SEATTLE II]; NCT01513759).

Final results of the Chronic Total Occlusion Crossing With the Ocelot System II (CONNECT II) study.

PURPOSE: To evaluate the safety and effectiveness of the optical coherence tomography-guided Ocelot catheter to cross femoropopliteal chronic total occlusions (CTOs). METHODS: The CONNECT II study was a prospective, multicenter, non-randomized single-arm study of the safety and effectiveness of the Ocelot catheter in CTO crossing. Key inclusion criteria were a 99% to 100% stenosed femoropopliteal segment, lesion length between 1 and 30 cm, and resistance to guidewire crossing. The main exclusion criterion was a severely calcified target vessel. The primary safety endpoint was 30-day major adverse events (MAE), while the primary effectiveness endpoint was successful CTO crossing (i.e., guidewire placement in the distal true lumen) with the Ocelot catheter. Endpoint analysis was based on pre-specified objective performance criteria. Between February and June 2012, 100 patients (55 men; mean age 69 years) were enrolled. Most of the CTOs (94%) were in the superficial femoral artery (SFA); mean lesion length was 16.6±9.3 cm. RESULTS: Through 30 days, 2 patients experienced MAE (significant perforations) related to the Ocelot catheter. The Ocelot catheter successfully crossed 97% of target CTOs either alone (72%), in conjunction with an assist device (18%), or in conjunction with a re-entry device (7%). Both primary safety and effectiveness endpoints were met. CONCLUSION: The Ocelot catheter with optical coherence tomography guidance offers physicians a reliable option for crossing femoral and popliteal chronic total occlusions with low MAE rates.

A multicenter experience evaluating chronic total occlusion crossing with the Wildcat catheter (the CONNECT study).

OBJECTIVE: Percutaneous techniques for crossing femoropopliteal chronic total occlusions (CTOs) offer an alternative to bypass surgery in patients deemed to be at increased risk due to advanced age or comorbidities. Recent reports document good success rates in catheters designed to reconstitute peripherally occluded arteries following failed guidewire passage. The Wildcat catheter (Avinger, Redwood City, Calif) is a novel device with a rotating distal tip and deployable wedges fashioned for channeling a passage through arterial occlusions. This report describes the results of a prospective, multicenter, nonrandomized trial evaluating the safety and efficacy of the Wildcat device when crossing de novo or restenotic femoropopliteal CTOs. METHODS: Between August 2010 and April 2011, patients with peripheral arterial disease due to a femoropopliteal CTO>1 cm and ≤35 cm were evaluated for study enrollment at 15 U.S. sites. During treatment, the physician initially attempted to cross the CTO using conventional guidewires per protocol; if the guidewire successfully crossed, the patient was considered a screen failure and the Wildcat was not deployed. At 30 days, patients were reevaluated. The primary efficacy end point was successful crossing of the Wildcat into the distal true lumen as confirmed by angiography. Primary safety end points included no in-hospital or 30-day major adverse events, no clinically significant perforation or embolization, and no grade C or greater dissection. Additional data collected included lesion length, degree of calcification, and location. RESULTS: Eighty-eight patients were enrolled in the trial. Of these, the Wildcat device was used in 84 patients (95%) per protocol. Successful CTO crossing was reported and confirmed by independent review in 89% (75/84) of cases with 5% (4/84) major adverse events as defined in the protocol (predominantly perforations sealed with balloon inflation). There were no clinically relevant events associated with any of the perforations. The mean CTO length was 174±96 mm (range, 15-350 mm). Approximately 57% (n=48) of all lesions were categorized as containing at least moderate calcification. Eighty-nine percent (n=75) of vessels recanalized were superficial femoral arteries. CONCLUSIONS: In this multicenter study, the Wildcat catheter demonstrated an 89% crossing success rate with little associated morbidity. The Wildcat catheter is a viable device for crossing moderately calcified femoropopliteal CTOs.