Abstract Optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) offers more in-depth assessment of plaque morphology, vessel sizing and post-PCI stent deployment characteristics than angiography guidance alone. Previous studies have demonstrated superiority of OCT-guided compared to angiography-guided PCI in stent implantation and expansion, with no difference in safety outcomes. Despite this, adoption of OCT-guided PCI remains low in clinical practice due to its increased procedural time, larger contrast volume, and added cost. Two large multicentre international randomised controlled trials (RCTs) were recently published. We therefore aimed to perform an up-to-date meta-analysis of RCTs comparing OCT-guided revascularisation against angiography-guided revascularisation on hard clinical outcomes. A comprehensive search of PubMed/MEDLINE and Ovid/Embase was performed, of which only RCTs were included. Two authors identified relevant articles and extracted the data independently. Any disagreements were resolved by a third author. Clinical outcome data was extracted from each study and then pooled to determine the overall risk ratio (RR) and confidence interval (CI) collectively. This was calculated with random-effects model using the Mantel-Haenszel method. All reported P values are two-sided, with significance set at P<0.05. A total of ten RCTs involving a total of 5062 patients were included. After an average follow-up of 20 months, there was no significant difference in the trial-defined composite endpoint between OCT-guided versus angiography guided revascularisation [6.8% versus 7.9%, RR 0.85, 95% CI (0.69 to 1.03), P=0.10, heterogeneity (I2)=0%]. There was also no significant difference in cardiac death [1.0% versus 1.6%, RR 0.61, 95% CI (0.36 to 1.02), P=0.06, heterogeneity (I2)=0%, Figure 1a], myocardial infarction [3.2% versus 3.7%, RR 0.86, 95% CI (0.65 to 1.15), P=0.31, I2=0%, Figure 1b] and target lesion or vessel repeat revascularisation [3.8% versus 4.1%, RR 0.95, 95% CI (0.72 to 1.25), P=0.70, I2=0%, Figure 1c] between the two arms. However, the OCT-guided revascularisation arm was associated with a significantly lower rate of stent thrombosis [0.8% versus 1.5%, RR 0.57, 95% CI (0.33 to 0.97), P=0.04, I2=0%, Figure 1d] than the angiography-guided revascularisation arm. The number-needed-to-treat (NNT) by OCT-guided revascularisation to reduce one additional stent thrombosis event was 143. In conclusion, our findings show the use of OCT-guided revascularisation led to a significant reduction in stent thrombosis compared to angiography-guided revascularisation, but there was no difference in cardiac death, myocardial infarction and repeat revascularisation. The NNT for stent thrombosis was 143 patients. Further research is needed to identity those subgroups most likely to benefit from OCT-guided revascularisation before it can be more widely adopted to significantly impact on clinical care.