Introduction and methods

COMPLETE Revascularization with Multivessel Percutaneous Coronary Intervention in Stsegment Elevation Myocardial Infarction

Presented at ESC Congress 2019 in Paris, France by Doctor Shamir R MEHTA (Hamilton, ON, Canada)

Patients undergoing primary percutaneous coronary intervention (PCI) to the culprit lesion for STEMI are often found to have multivessel CAD, with one or more angiographically significant non-culprit lesions. There is uncertainty on how best to manage these non-culprit lesions: should we routinely revascularize them with PCI? Or manage them conservatively with guideline-directed medical therapy alone?

While prior randomized clinical trials (RCTs) have shown non-culprit lesion PCI reduces revascularization, none were powered to detect moderate reductions in hard clinical outcomes such as CV death or myocardial infarction (MI). Meta-analyses have suggested a possible reduction in CV death or MI, but this result is fragile and no single RCT has been adequately powered to confirm this. The COMPLETE trial was designed to address this evidence gap.

Patients with STEMI with multivessel CAD and successful PCI to the culprit lesion were randomized to either complete revascularization (n=2016, routine staged PCI of all suitable non-culprit lesions [NCL] with the goal of complete revascularization) or to culprit lesion only revascularization (n=2025, no further revascularization of NCL). All patients received guideline-directed medical therapy. The complete revascularization was performed irrespective of whether patients had symptoms or not. Median follow-up was 3 years. The co-primary endpoints were the composite of CV death or new MI, and the composite of CV death, new MI or ischemia driven revascularization (IDR). Patients were recruited globally in 140 centres in 31 countries, with the largest part in Europe (1907) and North America (1778). The baseline characteristics were very compatible with a STEMI population. Patients were exceptionally well treated and >71% received ticagrelor or prasugrel at discharge.

Main results

• Complete revascularization was achieved in 90.1% after NCL-PCI, with SYNTAX score = 0, meaning there was no residual disease.
• The first co-primary outcome of CV death or new MI was seen less often in the complete revascularization group, as compared with the culprit only-group (2.7 vs. 3.7 %/year, HR: 0.74, 95%CI: 0.60-0.91, P=0.004), with a number needed to treat (NNT) over a median of 3 years, of 37.
• The second co-primary outcome of CV death, new MI or IDR was seen less often in the complete revascularization group, as compared with the culprit only-group (3.1 vs. 6.2 %/year, HR: 0.51, 95%CI: 0.43-0.61, P<0.1, with NNT of 13.
• The key secondary outcome of CV death, MI, IDR, unstable angina or class IV HF was also seen less often in the complete revascularization group than in the culprit-lesion group (4.9 vs. 8.1%, HR: 0.62, 95%CI: 0.53-0.72, P<0.001).
• Other significantly reduced secondary outcomes were MI (HR: 0.68), IDR (HR: 0.18) and unstable angina (HR: 0.53). CV death and all-cause death were not found to be significantly different between groups.
• An analysis looked into the effect of timing of the NCL PCI, by comparing the effect of during or after initial hospitalization. Median time to study NCL PCI in the complete group was 1 day (IQR: 1-3) for during the initial hospitalization, and 23 days for after hospital discharge (IQR: 12.5 – 33.5). No interaction (P=0.62) of timing was seen on the effect on CV death or new MI (HR: 0.77 during vs. 0.69 after), nor on CV death, new MI or IDR (p-interaction: 0.27, HR: 0.47 during vs 0.59 after).
• No significant differences were seen between the groups in safety and other outcomes, including stroke, stent thrombosis, major bleeding, acute kidney injury and NYHA class IV heart failure.

Conclusions

This study shows that in patients with STEMI and multi-vessel CAD, routine non-culprit lesion PCI with the goal of complete revascularization reduced CV death or new MI by 26% and CV death, new MI or IDR by 49%, as compared with culprit-lesion-only PCI. The benefit of complete revascularization was similar in those undergoing NCL PCI during the index-hospitalization and several weeks after hospital discharge. This can be explained by the fact that the benefits occur over the long term.

Discussion

During the press conference, dr Mehta was asked whether he saw these results as definite. With regard to the hard endpoints, his answer was yes. The time results are less definitive, but they point to later intervention probably being fine and earlier not being dangerous. The main message is that events occur in the long term, and they can be prevented.

- Our reporting is based on the information provided at the ESC congress -

This article was simultaneously published in N Eng J Med