Novel high-frequency vibration approach for recanalization of difficult coronary and peripheral chronic total occlusions

In all of endovascular medicine, the most challenging subset of lesions to treat remains chronic total occlusions (CTOs). Treatment options for CTOs, both in the coronary and peripheral vasculature, continue to be a significant unmet clinical need and opportunity facing interventional cardiology. CTOs usually comprise of a combination of fibrocalcific and thrombotic elements that have been in existence for more than 30 days. There is inconsistency and a lack of consensus in the literature here, as some have defined CTOs anywhere from 2 weeks [1–3] to 3 months [2,4]. Chronically occluded coronary arteries account for approximately a third of patients undergoing diagnostic coronary angiography [5]. At present, there are three methods for treatment of coronary CTOs: percutaneous intervention, coronary artery bypass surgery and medical management. New-wire strategies to treat CTOs, such as the retrograde approach, appear promising [6]; however, these procedures require suitable anatomy, a specific armamentarium and are generally challenging procedures that cannot be performed in all high-volume centers. These new tools and approaches need to be used thoughtfully and in the right anatomical and clinical context. Similar to coronary artery disease, peripheral artery occlusive disease (PAOD) – at a conservative estimate – affects between 6 and 12 million people in the USA alone and is associated with significant long-term morbidity, mortality and reduction in quality of life. Of these patients, 50% have one or more chronically occluded lower extremity arteries that cause PAOD symptoms [7]. Currently, there are four methods for treatment of lower extremity CTOs: conservative management, peripheral bypass surgery, amputation or percutaneous intervention [8]. Conservative management for PAOD, such as medical therapy, diet modification, smoking cessation and exercise, is partially efficacious, but rarely completely eliminates either the symptoms or the objective evidence of the ischemia [7]. It tends to be lifestyle-limiting and the pain that that often accompanies exertional activity causes the patients to avoid exercise, which often leads to weight gain, glucose intolerance and a downward spiral to lassitude and senescence. Peripheral artery bypass surgery is effective so long as the distal target vessel is anatomically suitable for insertion of a bypass graft. The limitations of the bypass surgery are well known and include significant patient morbidity, risk of surgical mortality and significant expense, as well as Chronic total occlusions (CTOs) continue to be quite prevalent and still present as some of the most challenging lesions for the coronary and/or peripheral interventionalist. Recanalization success rates have been historically low and the potential for adverse events are typically higher than the more common procedures of angioplasty and stenting. At present, there are two paths to successful CTO recanalization; the subintimal approach and the central lumen approach. The subintimal approach tracks a standard guidewire around the occlusion and through the subintimal plane, while the luminal approach attempts to recanalize the occlusion through the central lumen of the artery. After failure to stay in the true lumen, a bypass is essentially created around the occlusion through the adventitia. This may lead to adverse events. A central luminal approach may provide increased safety and more therapeutic options to the clinician and may ultimately deliver enhanced longer-term outcomes owing to the optimization of luminal therapy. In this article, we investigate the CROSSER® catheter as a device that may allow physicians to recanalize coronary and peripheral CTOs in the central lumen, thereby maximizing the therapeutic options and optimizing longer-term results.