Percutaneous photoacoustic debulking of infra-inguinal atherosclerotic disease- early European experience with a novel, solid-state, pulsed -wave, ultraviolet 355 nm laser

The broad spectrum of clinical manifestations caused by peripheral arterial disease [PAD] and the morphologic heterogeneity of associated atherosclerotic lesions present a considerable management challenge. Endovascular interventions are recognized an effective treatment for PAD. Within this revascularization strategy the role of atherectomy debulking modalities continue to evolve. Accordingly, the study herein assessed the efficacy and safety of a novel, solid state, Nd: YAG pulsed-wave [355 nm wavelength] laser atherectomy in the treatment of symptomatic infra-inguinal PAD. The EX-PAD-01 study, a prospective, single-arm, open label trial enrolled 50 patients (38 males, 12 females; mean age 64 years] with symptomatic peripheral arterial disease, who underwent percutaneous revascularization with a novel, solid state, pulsed-wave [355 nm wavelength] laser atherectomy followed with adjunct treatment. The Ankle-brachial index [ABI], Rutherford classification for chronic limb ischemia and the walking impairment questionnaire [WIQ] were used for assessment of the index clinical condition of the enrolled patients, for post procedure evaluation and during follow-up. Accordingly, the patients were followed for 12-months with repeated direct physician contact visits. Fifty-three atherosclerotic stenoses (51 femoropopliteal, 2 tibial) with a mean length of 7.4 cm. (ranged 1cm to 25cm) were treated. There were 79% occlusions, and 61% containing moderate-to-severe calcifications. The pre-procedure stenosis was 95.3 ± 10.3%, the Rutherford classification for chronic limb ischemia [CLI] was 2.90 ± 0.54 ranging between 2-4 and the WIQ 34.6 ± 8.62. Technical success was achieved in 52 of the 53 (98%) target lesions. Following laser debulking the baseline stenosis was reduced from 95.3 ± 10.3% to 61.3 ± 25.5% [ [p < 0.0001] and with adjunct balloon/stenting to final of 14.0 ± 14.0% [p < 0.0001]. Embolic protection devices were utilized in 6 [12%] patients. At 30-day post procedure evaluation the ABI increased from baseline of 0.57 ± 0.14 to 0.94 ± 0.14 [p < 0.0001] and no major adverse effects or device adverse effects were detected. At 6 months follow -up the ABI was 0.84 ± 0.20% (p < 0.0001 vs. initial) and at 1 year follow-up 0.79 ± 0.16 (P = 0.0001 vs. initial) without major adverse events. Out of 46 [92%] patients who reached the 12 months follow-up mark, 2 [4.3%] experienced clinically driven target lesion revascularization. Sustained clinical benefit for up to 12 months post procedure was demonstrated through documentation of statistically significant decrease of Rutherford CLI class as well as concomitant improvement in WIQ score and an increase of ABI value. The primary patency rate, as defined by peak systolic velocity ratio (PSVR) of < 2.5m/second was 95.7% (22 of 23) and 81.8% (18 of 22) at 6 months and 12 months, respectively. In an early European clinical experience with a series of 50 patients with symptomatic peripheral arterial disease, the novel Nd: YAG solid state, pulsed- wave 355nm cardiovascular laser atherectomy device provided effective and safe revascularization treatment. Follow-up at 6 and 12 months, respectively, substantiate the efficacy, safety profile and clinical merits of this novel laser. Thus, this device is useful in the management of select patients with symptomatic infra-inguinal atherosclerotic lesions.Clinical Trial Registration: Clinical trials.gov number: NTC02556255.