Background: Optical coherence tomography (OCT) allows for precise analysis of coronary artery morphology and optimized planning of revascularization. Following stent implantation OCT might detect edge dissection, underexpansion, malapposition, or residual disease and might contribute to additional treatment approaches. The applicability of OCT in percutaneous coronary intervention (PCI) was demonstrated in elective settings before, but data on efficacy under urgent conditions during acute coronary syndrome (ACS) are limited. The current meta-analysis aimed to assess the effects of OCT-guided vs. angiography-guided PCI in treatment of ACS.

Methods: A literature search was performed using Medline, Web of Sciences, and Cochrane Library to identify potential studies published since implementation of each database. The last search was performed on 31.10.2022. Records and full-text articles were independently screened by two authors (SMM, MM). All randomized and non-randomized controlled trials (RCT and non-RCT) assessing the effect of OCT-guided vs. angiography-guided PCI in patients with ACS were eligible. In non-randomized trials, matched data were preferred over crude data. ACS was defined as ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), or unstable angina. The primary end point was major adverse cardiac events (MACE), a composite of cardiac mortality, myocardial infarction, and target vessel revascularization. The individual components and all-cause mortality were separately analyzed as secondary efficacy endpoints.

Results: Seven cohorts reporting on 2512 patients with ACS were eligible for quantitative analysis. Of these, 78.7% were male, 63.8% had hypertension, 23.1% had diabetes, 58.2% had dyslipidemia and 49.3% were smoker. The median age ranged from 54.5 to 73 years. STEMI (64.4%) was the predominant type of ACS, followed by NSTEMI (27%) and unstabile angina (9.8%). 1213 patients underwent OCT-guided and 1299 patients angiography-guided PCI (including 197 patients with additional fractional-flow reserve calculation). The median follow-up ranged from 6 to 25 months. OCT-guided PCI was associated with a 30% lower likelihood of MACE in comparison to angiography-guided PCI (n=6 trials, OR 0.70; 95% CI: 0.52-0.96, p=0.03, I²: 15%, figure 1). OCT-guided PCI significantly decreased cardiac mortality compared to angiography (n=3 trials, OR 0.50; 95% CI: 0.25-0.99, p=0.05, I²: 0%). But the comparison of OCT-guided and angiography-guided PCI did not result in a difference in all-cause mortality (n=4 trials, OR 1.21; 95% CI: 0.5-2.96, p=0.67, I²: 13%). The risk of subsequent myocardial infarction was not different between the groups (n=6 trials, OR 0.84; 95% CI: 0.5-1.41, p=0.50, I²: 0%). The need for target vessel (n=6 trials, OR 0.55; 95% CI: 0.25-1.22, p=0.14, I²: 54%) or target lesion revascularization did not significantly differ between the groups (n=2 trials, OR 0.24; 95% CI: 0.05-1.12, p=0.07, I²: 15).

PCI guided by OCT was associated with significantly lower rate of major adverse cardiac events compared to angiography in patients with acute coronary syndrome. This advantage was driven primarily by decreased cardiac mortality. These data show a potential benefit of use of OCT in ACS.