December 15th, 2014
The Latest on Culprit-Vessel vs. Multivessel Primary PCI for STEMI
Bilal Iqbal, MBBS MRCP PhD and CardioExchange Editors, Staff
The CardioExchange editors interview M. Bilal Iqbal about his study group’s real-world observational analysis of culprit-vessel versus multivessel intervention at the time of primary PCI for STEMI. The study is published in Circulation: Cardiovascular Quality and Outcomes.
CardioExchange: How do your data, results from the PRAMI trial, and findings from the unpublished CVLPRIT trial differ? And what conclusions can we draw from all of these data?
Iqbal: Certainly, a lot of recent data explores revascularization strategies for STEMI patients with multivessel disease, and the recent PRAMI and CVLPRIT randomized trials add to the evidence base. These important studies, together with future randomized trials, will define how we manage bystander coronary artery disease at the time of primary PCI. I’m not sure our observational study tells us anything new compared with previously reported registry analyses, but it does offer a more contemporary analysis in a real-world setting. We must acknowledge the limitations of observational analyses. Although we used various statistical methodologies to address measured confounders, unmeasured confounders may have affected the results. Therefore, our results should be considered hypothesis-generating.
In the CVLPRIT trial, a strategy of complete revascularization before hospital discharge was associated with improved outcomes. The PRAMI trial found that a strategy of complete revascularization at the time of primary PCI was associated with improved outcomes. Although the two trials suggest that complete revascularization is a superior strategy, the composite endpoints in these studies included outcomes that may themselves be dictated by treatment strategy (e.g., refractory angina, ischemia-driven revascularization).
In our study, the main outcome analyzed was mortality. With respect to mortality, no difference was found between the two strategies in either PRAMI or CVLPRIT. Furthermore, our study looked specifically at culprit-vessel versus multivessel intervention at the time of primary PCI (index intervention procedure), whereas CVLPIRT studied complete versus incomplete revascularization before hospital discharge. Notably, in CVLPRIT, 57% of the patients underwent multivessel revascularization at the time of the primary PCI, and the rest received complete revascularization before discharge. An important question stemming from CVLPRIT is whether outcomes are better with complete revascularization at the time of primary PCI or before hospital discharge.
CardioExchange: STEMI guidelines have traditionally recommended culprit-vessel intervention alone. Do you think the issue needs to be re-addressed by the guidelines, or are the data from your study sufficient to leave them as they are?
Iqbal: Again, our study is observational and should only be considered hypothesis-generating. Given the results of PRAMI and CVLRIT, it is clear that the issue needs to be re-addressed in the guidelines. However, further trials are required to define the optimum revascularization for patients and with STEMI and multivessel disease. We must wait and see what future studies tell us.
CardioExchange: If you have a patient who comes in with STEMI and other lesions, what are you recommending?
Iqbal: At present, our practice reflects current recommended guidelines, and we perform culprit-only PCI in the absence of cardiogenic shock and/or ongoing ischemia.
JOIN THE DISCUSSION
How does Dr. Iqbal’s study influence your perceptions of culprit-vessel versus multivessel primary PCI for STEMI?