Severe Acute Stent Malapposition After Drug-Eluting Stent Implantation: Effects on Long-Term Clinical Outcomes

Abstract

Background Theeffectsofsevereacutestentmalapposition( ASM )afterdrug-eluting stentimplantationonlong-termclinicaloutcomesare not clearly understood. We evaluatedlong-termclinicaloutcomesofsevereASM using optical coherence tomography. Methods and Results We pooled patient- and lesion-level data from 6 randomized studies. Five studies investigated follow-updrug-eluting stentstrut coverage and one investigated ASM . In this data set, a total of 436 patients with 444 lesions underwent postintervention optical coherence tomography examination and these data were included in the analysis.SevereASM was defined as lesions with ≥400μm of maximum malapposed distance or ≥1mm of maximum malapposed length. Composite events (cardiac death, target lesion-related myocardial infarction, target lesion revascularization, andstentthrombosis) were compared between patients with and withoutsevereASM . The postintervention optical coherence tomography findings indicated that 62 (14.2%) patients had lesions with ≥400μm of maximum malapposed distance and 186 (42.7%) patients had lesions with ≥1mm of maximum malapposed length. The 5-yearclinicalfollow-up was completed in 371 (86.1%) of the eligible 431 patients. The cumulative rate of composite events was similar among the patients in each group during 5-year follow-up: 3.3% in patients with ASM ≥400μm of maximum malapposed distance versus 3.1% in those with no ASM or ASM <400μm of maximum malapposed distance ( P=0.89), and 1.2% in patients with ASM ≥1mm of maximum malapposed length versus 4.6% in those with no ASM or ASM <1mm of maximum malapposed length ( P=0.06). Conclusions During the 5-year follow-up, ASMseveritywas not associated withlong-termclinicaloutcomesin patients treated withdrug-eluting stents.