“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,” said Glenn N. Levine, MD, FACC, FAHA, cochair of the writing committee, 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. He is also chair-elect of the ACC/AHA Task Force on Clinical Practice Guidelines.
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 IIb recommendation).
In past iterations of the guidelines, treatment of other partially blocked arteries at the time of primary PCI was given a Class III-harm recommendation. This recommendation was based on prior 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 that “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 IIb 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. As well, in three of the four studies, multivessel PCI was beneficial.
The best timing to treat non-culprit arteries, however, 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 prior to a primary PCI procedure to implant a stent, using a device to aspirate or create suction to remove the blood clot from the blocked artery, was downgraded to Class III (no benefit) from Class IIa (is reasonable) for patients with a heart attack due to completely blocked arteries. The change in this recommendation was based on the results of three recent randomized trials (INFUSE-MI, TASTE, and TOTAL), as well as an analysis of all available data on this procedure.
“Based on new evidence, the writing group concluded that there was no benefit with the routine use of aspiration thrombectomy,” stated Dr. Levine. 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.
“This document is intended to provide a timely update based on new evidence to assist clinical decision-making,” stated Dr. Levine. The main document and its online data supplement provide further details to inform decision-making in individual cases.
Download the “2015 ACC/AHA/SCAI Focused Update on Primary Percutaneous Coronary Intervention for Patients With ST-Elevation Myocardial Infarction: An Update of the 2011 ACCF/AHA/SCAI Guideline for Percutaneous Coronary Intervention and the 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction”
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