LAUSR

The transradial approach (TRA) for percutaneous coronary intervention (PCI) has gained widespread acceptance during the past few decades. The radial artery is easily compressible, not surrounded by major venous and nervous structures, and an adequate collateral arterial network is present. As a result, the risk of vascular complications after TRA is negligible. Multiple randomized trials demonstrated that a transfemoral approach (TFA) is associated with a significantly higher risk of bleeding, pseudoaneurysm and arteriovenous fistula formation, cardiac events, and mortality after PCI. This has been demonstrated in PCI for stable coronary artery disease and acute coronary syndromes, both with and without persistent ST-segment elevation. Moreover, vascular complication rates after TFA are only modestly reduced using vascular closure devices. In chronic total occlusion (CTO), a hybrid approach is increasingly being used to achieve revascularization: use of dual arterial access is the key to improve the safety and effectiveness of the procedure. CTO PCI procedures are commonly performed by means of largebore, dual-catheter TFA as routine strategy without using radial access. Nevertheless, the feasibility of a fully transradial (fTRA) approach in CTO PCI has already been documented, and several observational studies have shown promising results in terms of application of lesion complexity and procedural success rates when compared with those of the conventional TFA. Of interest, a recent subanalysis of the RECHARGE registry investigating the procedural outcomes of CTO PCI performed by an fTRA approach has reported comparable success rates as compared with transfemoral procedures, including subgroups of patients with higher lesion complexity (J-CTO score ≥ 3). Starting from this perspective, the so-called “Minimalistic Hybrid Algorithm” has the purpose to minimize the use of double access, large-bore catheters, and femoral approach without compromising efficacy, adopting a revascularization strategy that maintains available all the four possible options for crossing the CTO lesions (the antegrade wire escalation or antegrade dissection re-entry, the retrograde wire escalation, and retrograde dissection re-entry). However, the order in which they are attempted is focused on the priority of minimizing double access and femoral approach. In this issue of Catheterization and Cardiovascular Interventions, Zivelonghi et al bring the minimalist approach into the CTO PCI arena. They evaluated the results and the outcome of 100 consecutive patients undergoing CTO PCI between March 2016 and October 2017 using the so-called “Minimalistic Hybrid Algorithm.” All CTO complexity scenarios were observed in the minimalistic approach group, and the mean J-CTO score was 1.9 ± 1.2 and PROGRESS was 0.9 ± 0.9. Very complex CTO lesions (namely, J-CTO score ≥ 3) constituted one-third (33.2%) of the patients in the “minimalistic approach” group lesions with lower complexity scores and the presence of microchannel or nonambiguous cap could be approached with a single 6F catheter (transradial or transulnar) without contralateral injection and by means of antegrade wire escalation with soft wires supported by a microcatheter. In the case of an ineffective procedure, in the presence of interventional collaterals, the same radial/ulnar access should be converted to a retrograde access and adopted to attempt retrograde collateral crossing, then followed (in the case of successful retrograde collateral crossing) by a second 6F transradial/ transulnar access for antegrade approach and procedural completion by means of retrograde wire escalation or reverse-controlled antegrade and retrograde subintimal tracking (R-CART). Of the 100 CTO PCI performed in the study period, 91(91%) were successfully approached according to the algorithm. It is noteworthy that in 52 procedures, the approach consisted of single catheter access, 94.2% of which were transradial. All available techniques were successfully adopted including 20 (24.7%) R-CART techniques. Overall Received: 20 December 2019 Accepted: 20 December 2019