NEW YORK (Reuters Health) – For STEMI patients with multivessel coronary disease undergoing primary percutaneous coronary intervention, outcomes are better when revascularization is targeted to just the culprit vessel rather than to multiple coronary lesions, according to a new study.

“This meta-analysis supports current guidelines discouraging performance of multivessel primary PCI for STEMI,” the authors advise in the August 9 issue of the Journal of the American College of Cardiology. “When significant nonculprit vessel lesions are suitable for PCI, they should only be treated during staged procedures.”

Dr. Pieter J. Vlaar, with University Medical Center Groningen in the Netherlands, and colleagues note that up to 65% of patients with ST-segment elevation myocardial infarction have multivessel disease. Current guidelines recommend primary PCI should be confined to culprit lesions, but other strategies are to perform PCI on culprit and nonculprit lesions at the same time, or to treat culprit lesions first followed by staged procedures on nonculprit lesions.

To compare these three strategies, the team identified four prospective and 14 retrospective studies comparing either all three approaches or permutations of two of the three strategies. The data covered a total of 40,280 patients with ST-elevation MI and multivessel disease.

A meta-analysis of the pooled data indicated that, compared with the staged PCI strategy, short-term mortality was worse with PCI of the culprit lesion only (odds ratio 3.03) or with multivessel PCI (odds ratio 5.31).

Short-term mortality was better with culprit PCI than multivessel PCI in general (odds ratio 0.66) and in cases of cardiogenic shock (odds ratio 0.68), according to the report.

Long-term outcomes followed the same pattern, with multivessel PCI consistently associated with the highest mortality rates.

In discussing the findings, Dr. Vlaar and colleagues point out that the timing of the staged procedures or switching to coronary artery bypass were not investigated in the studies.

They conclude, “More prospective research should be performed to investigate which strategy is superior in both hemodynamic stable and unstable STEMI patients (CABG vs. culprit PCI vs. staged PCI vs. multivessel PCI). We, therefore, propose a prospective international registry to investigate these strategies.”

Meanwhile, the findings are supported by another paper in the journal. Dr. Ran Kornowski, at the Rabin Medical Center in Petah Tikva, Israel, and colleagues report on a subset of 668 STEMI patients with multivessel disease in the HORIZONS-AMI trial who received PCI on multiple vessels in a single procedure or in staged procedures.

One-year mortality rates in the two groups were 9.2% vs. 2.3%, respectively, yielding a hazard ratio of: 4.1 (p<0.0001) with the single-procedure approach, the researchers found. There was also a trend toward greater 1-year rates of major adverse cardiovascular events (18.1% vs 13.4%, p=0.08).

In an accompanying editorial, Dr. John A. Bittl, with the Ocala Heart Institute in Florida, notes that these findings cannot be applied to every situation. “Multivessel PCI may be necessary in some STEMI patients who have multiple complex lesions and do not improve after culprit PCI,” he writes.

J Am Coll Cardiol 2011;58:692–714.