title: Mechanisms, pathophysiology, and clinical aspects of incomplete stent apposition.
abstract: Incomplete stent apposition (ISA) is characterized by the lack of contact of at least 1 stent strut with the vessel wall in a segment not overlying a side branch; it is more commonly found in drug-eluting stents than bare-metal stents. The accurate diagnosis of ISA, initially only possible with intravascular ultrasound, can currently be performed with higher accuracy by optical coherence tomography, which also enables strut-level assessment due to its higher axial resolution. Different circumstances related both to the index procedure and to vascular healing might influence ISA occurrence. Although several histopathology and clinical studies linked ISA to stent thrombosis, potential selection bias precluded definitive conclusions. Initial studies usually performed single time point assessments comparing overall ISA percentage and magnitude in different groups (i.e., stent type), thus hampering a comprehensive understanding of its relationship with vascular healing. Serial intravascular imaging studies that evaluated vascular response heterogeneity recently helped fill this gap. Some particular clinical scenarios such as acute coronary syndromes, bifurcations, tapered vessels, overlapping stents, and chronic total occlusions might predispose to ISA. Interventional cardiologists should be committed to optimal stent choices and techniques of implantation and use intravascular imaging guidance when appropriate to aim at minimizing acute ISA. In addition, the active search for new stent platforms that could accommodate vessel remodeling over time (i.e., self-expandable stents) and for new polymers and/or eluting drugs that could induce less inflammation (hence, less positive remodeling) could ultimately reduce the occurrence of ISA and its potentially harmful consequences.
authors: Division of Cardiology, Ferrarotto Hospital, University of Catania, Catania, Italy; Division of Interventional Cardiology, Pitangueiras Hospital, Jundiaí, SP, Brazil; Harrington Heart and Vascular Institute, University Hospitals, Case Medical Center, Cleveland, Ohio.
authors: Guilherme F
authors: GF
authors: Attizzani
authors: Division of Cardiology, Ferrarotto Hospital, University of Catania, Catania, Italy; Excellence Through Newest Advances (ETNA) Foundation, Catania, Italy. Electronic address: dcapodanno@gmail.com.
authors: Davide
authors: D
authors: Capodanno
authors: Division of Cardiology, Ferrarotto Hospital, University of Catania, Catania, Italy.
authors: Yohei
authors: Y
authors: Ohno
authors: Division of Cardiology, Ferrarotto Hospital, University of Catania, Catania, Italy; Excellence Through Newest Advances (ETNA) Foundation, Catania, Italy.
authors: Corrado
authors: C
authors: Tamburino
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects* / Q000379:methods; D017023:Coronary Angiography / Q000379:methods; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000401:mortality / Q000473:pathology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy*; D003328:Coronary Thrombosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000401:mortality / Q000473:pathology*; D054855:Drug-Eluting Stents / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011475:Prosthesis Failure; D018570:Risk Assessment; D012720:Severity of Illness Index; D020123:Sirolimus / Q000627:therapeutic use; D015607:Stents / Q000009:adverse effects*; D015996:Survival Rate; D041623:Tomography, Optical Coherence
chemical_list: D020123:Sirolimus
keywords: drug-eluting stent(s); incomplete stent apposition; intravascular ultrasound; optical coherence tomography; percutaneous coronary intervention; stent malapposition