LAUSR

Recently, the SINGA-PACLI TRIAL, a randomized controlled trial comparing drug-coated balloon angioplasty (DCBA) (Passeo-18 Lux, Biotronik; with 3 lg of paclitaxel per square millimeter of balloon surface coated in a delivery matrix of n-Butyryl tri-n-hexyl citrate) versus conventional balloon angioplasty (PTA) (Passeo-18, Biotronik) for treating below-the-knee arteries (BTK) in critical limb ischemia (CLI), was published in ‘‘Radiology’’ [1]. In this prospective double-blind superiority study, patients with critical limb ischemia and atherosclerotic disease in the below-the-knee-arteries were randomized for DCBA or PTA after stratification for diabetes and renal failure. The primary efficacy endpoint was angiographic primary patency (less than 50% stenosis at angiography) at 6 months. Secondary endpoints through 12 months were composed of major adverse events including death and major amputation, wound healing, limb salvage, clinically driven target lesion revascularization and amputation-free survival. There was no significant difference regarding the primary endpoint at 6 months, in the DCBA group (30 of 70 (43%) patients) versus the PTA group (26 of 68 (38%) patients) (P = 0.48). Amputation-free survival was significantly better through 12 months in the PTA group (53 of 68 (78%) patients) versus the DCBA group (41 of 70 (59%) of patients) (P = 0.01). The percentage of death was similar through 12 months in both groups; 21% in the DCBA group vs 16% in the PTA group (P = 0.43). The authors conclude that their trial failed to meet its primary efficacy end point of superior 6-months primary patency of DCBA compared with PTA and that among the secondary efficacy and clinical end points only amputationfree survival over 12 months was significantly different, in favor of PTA. The authors discuss that, similar to the IN.PACT-DEEP and BIOLUX P-II trials, the SINGA-PACLI Trial shows no efficacy benefit of DCBA versus PTA. The IN.PACTDEEP trial reported an increased major amputation rate at 12 months for DCBA [2]. Although there is no clear explanation for these findings, it has been suggested that embolization of medication applied to the PTA balloon may have contributed to the results. The authors of the present trial again cannot give an explanation for the difference in amputation-free survival in disfavor for the DCBA group. Regarding these negative findings, however, we should remain cautious before using DCB below the knee in patients with CLI. Perhaps our expectations are too high when pushing coated balloons through narrow and calcified crural arteries in an attempt to deliver drugs for a longer period to the arterial wall with a few minutes of balloon inflation. Although the results of drug-coated balloons (DCB) below the knee in CLI are again disappointing in the SINGA-PACLI trial, results of drug eluting stents (DES) BTK seem to be consistently better. The Achilles trial, YUKON-BTX, DESTINY and PADI trial all reported improved morphological and clinical results with the use of DES vs PTA or bare metal stents [3, 4]. Use of a metal scaffold may facilitate more consistent drug release. & Hans van Overhagen [email protected]