New Guidance Issued for Multivessel PCI and Thrombectomy in STEMI Patients

October 21, 2015—New guidance on the use of multivessel percutaneous coronary interventions (PCI) and thrombectomy in patients with myocardial infarction caused by completely blocked arteries was issued in a focused update from the American College of Cardiology, the American Heart Association, and the Society for Cardiovascular Angiography and Interventions, in collaboration with the American College of Emergency Physicians.

The focused update on primary PCI for patients with ST-elevation myocardial infarction (STEMI) was drafted by writing committee cochair Glenn N. Levine, MD, et al. It is available online in the Journal of the American College of Cardiology, Circulation, and Catheterization and Cardiovascular Interventions. The scope of the update was limited to the setting of primary PCI and the relevant considerations for multivessel PCI and thrombus aspiration, noted the societies. The main document and its online data supplement provide further details to inform decision making in individual cases.

In the announcement, Dr. Levine stated, “This document is intended to provide a timely update based on new evidence to assist clinical decision making.” Dr. Levine is Professor of Medicine at Baylor College of Medicine, and Director of the Cardiac Care Unit at the Michael E. DeBakey VA Medical Center in Houston, Texas. He is also Chair-elect of the ACC/AHA Task Force on Clinical Practice Guidelines.

According to the societies, new evidence from recent clinical trials has shown that treating other partially blocked arteries may be safe and beneficial in selected patients with multivessel disease. The focused update states that treating the other blocked arteries with a stent may be considered in patients with STEMI who are hemodynamically stable at the time of the primary PCI (class 2b recommendation).

In past iterations of the guidelines, treatment of other partially blocked arteries at the time of primary PCI was given a class 3-harm recommendation. This recommendation was based on previous nonrandomized study data, which suggested worse outcomes in patients who underwent contemporaneous PCI of vessels other than the one causing the heart attack.

The new recommendation states, “PCI of a noninfarct artery may be considered in selected patients with STEMI and multivessel disease who are hemodynamically stable, either at the time of primary PCI or as a planned staged procedure,” and designates this as a class 2b recommendation. This recommendation was based on the results from four recent randomized clinical trials (PRAMI, CvLPRIT, DANAMI 3-PRIMULTI, PRAGUE-13) that did not demonstrate an increased risk of harm when performing multivessel PCI. In three of the four studies, multivessel PCI was beneficial.

The best timing to treat nonculprit arteries is not known, and no recommendation on timing of treating these other arteries was made because of insufficient evidence. The focused update states that “physicians should integrate clinical data, lesion severity/complexity, and the risk of contrast nephropathy to determine the optimal strategy” when considering the indications for and timing of multivessel PCI (primary or staged).

Despite this change in the recommendation regarding multivessel PCI in hemodynamically stable patients, the writing committee emphasized that it is not an endorsement of its routine use in all patients with STEMI and multivessel disease.

The recommendation for the routine use of manual aspiration thrombectomy before a primary PCI procedure to implant a stent, use a device to aspirate, or create suction to remove the blood clot from the blocked artery, was downgraded to class 3 (no benefit) from class 2a (is reasonable) for patients with a heart attack caused by completely blocked arteries. The change in this recommendation was based on the results of three recent randomized trials (INFUSE-AMI, TASTE, and TOTAL), as well as an analysis of all available data on this procedure.

In the joint announcement, Dr. Levine commented, “While we knew that treating the culprit artery that is completely blocked by implanting a stent is beneficial, it was previously not considered safe to treat other partially blocked (nonculprit) arteries during the same procedure.” He added, “Based on new evidence, the writing group concluded that there was no benefit with the routine use of aspiration thrombectomy.” Whether a selective or “bailout” use of aspiration thrombectomy in some patients has any usefulness is not well established, and to date no specific patient subgroup that may benefit from aspiration thrombectomy has been identified.