Tip detection-antegrade dissection and re-entry method as a bailout technique for coronary perforation in chronic total occlusion intervention: a case report.

Background: Chronic total occlusion (CTO) percutaneous coronary intervention (PCI) increases the risk of complications. Case summary: In CTO-PCI of the right coronary artery, AnteOwl WR intravascular ultrasonography (AO-IVUS; Terumo Corp., Tokyo, Japan) revealed that the antegrade guidewire had entered the subintimal space just beyond the CTO entrance and created a perforation outside the vessel approximately 1 cm distal to it. As the distal part of the AO-IVUS was outside the vessel, its removal worsened the bleeding; hence, it was left in place. Tip detection-antegrade dissection and re-entry techniques were performed using a Conquest Pro 12 Sharpened Tip guidewire (Asahi Intecc Co., Ltd, Aichi, Japan). The Conquest Pro 12 Sharpened Tip guidewire successfully re-entered from the subintimal space into the true lumen immediately before the perforation site. Because the perforation and re-entry sites were adjacent to each other, a covered stent was placed, which enabled simultaneous haemostasis at the perforation site and recanalization of the CTO lesion. Discussion: Although AnteOwl WR intravascular ultrasonography (AO-IVUS)-based tip detection-antegrade dissection and re-entry is an advanced technique, we believe that it is valuable for various PCI cases.