Toward a sequential provisional coronary bifurcation stenting technique. From kissing balloon to re-POT sequence

The specific anatomy of coronary bifurcations makes them prime sites of atherogenesis and complicates revascularization. Account must be taken of the systematic difference in diameter between the 3 constituent vessels so as to minimize final side-branch ostium obstruction and maintain the law of conservation of flow, while respecting the bifurcation angles. Kissing balloon inflation (KBI) was long recommended, but never clearly demonstrated clinical benefit in single-stent provisional stenting. The detrimental proximal overstretch induced by simultaneous inflation of balloons, observed clinically and confirmed experimentally, probably explains this inefficacy. Advances in knowledge of bifurcation pathophysiology and experimental bench studies gradually led to the development of a new purely sequential technique, re-POT, without balloon juxtaposition, comprising 3 successive steps: (1) initial "proximal optimization technique" (POT), (2) side-branch opening, and (3) final POT. In contrast to KBI, re-POT has been progressively assessed from bench to first clinical study. The aim of the present review is to present the pathophysiological specificities of coronary bifurcations, and some explanations for the failure of KBI which led to the development of a new purely sequential coronary bifurcation provisional stenting strategy, based on re-POT.