DENVER — Patients with acute MI complicated by cardiogenic shock demonstrated significantly higher 30-day survival rates with culprit lesion PCI versus multivessel PCI, according to a new study that challenges current guidelines.

The findings, presented Oct. 30 at the annual Transcatheter Cardiovascular Therapeutics (TCT) scientific symposium, could immediately change practice, experts said. In a randomized clinical trial of 706 patients with multivessel disease, all-cause mortality at 30 days was 43.3 percent for those undergoing PCI on the culprit lesion only versus 51.5 percent for multivessel PCI. That’s a relative risk reduction of 16 percent.

The multicenter European study, called CULPRIT-SHOCK, is the largest randomized trial in cardiogenic shock, a relatively rare but dangerous condition in which the heart is unable to pump enough blood to meet the body’s needs. It is often fatal if immediate revascularization isn’t achieved.

“Once we knew this data, we stopped doing multivessel PCI in patients with cardiogenic shock,” said principal investigator Holger Thiele, MD, director of the Heart Center Leipzig at University Hospital in Leipzig, Germany. “We are now only doing culprit lesion-only PCI and then we assess the patient later on to see if the patient needs additional staged revascularization because these data are so convincing with the mortality reduction.”

In addition to presenting the research at TCT, Holger and colleagues published their paper simultaneously in The New England Journal of Medicine.

“I think this is a landmark study and absolutely it will change our practice in the U.S.,” said Cindy L. Grines, MD, chair of cardiology at the Hofstra Northwell School of Medicine, who was not involved in the study.

“We’ve jumped on the bandwagon regarding multivessel PCI after some of the trials in Europe in the study population, but I think registries always suggested that there was higher mortality and the benefits of multivessel PCI in the acute setting were really just the reduction of recurrent ischemia. With this landmark trial, I think we’re going to take a step back and really try to limit the patients treated with multivessel PCI, but that’s not to say they may not benefit from a staged procedure.”

Thiele and colleagues used the primary endpoint of 30-day mortality or severe renal failure requiring renal replacement therapy. Forty-six percent of culprit lesion patients met that endpoint compared to 55.4 percent of multivessel PCI patients. Thiele said the higher dosage of contrast dye related to longer multivessel procedures (250 milliliters on average vs. 190 mL) could be one reason for the additional complications, but said further research is necessary to determine the specific causes for lower risk in culprit lesion-only PCI.

Multiple panelists at TCT pointed out the overall mortality among the study population was still near 50 percent at 30 days, suggesting there is a long way to go in treating these patients.

But for now, Thiele suggested clinicians “keep it simple” regarding PCI for acute MI complicated by cardiogenic shock. Widespread use of the shorter, simpler technique should also provide an economic benefit as well, predicted David J. Cohen, MD, the director for cardiovascular research at Saint Luke’s Mid America Heart Institute in Kansas City, Missouri.

“This seems like a case where less is more. … It’s hard to believe an economic analysis would not show this is cost-saving as well, so I think this is a win-win,” he said.