Clinical Research & Data, Complete Revascularization, Protected PCI

TCT 2021: MCS During High-Risk PCI and PROTECT IV


Gregg W. Stone, MD, explores evidence for the use of mechanical circulatory support (MCS) during high-risk PCI (HRPCI) and provides an update on the ongoing PROTECT IV randomized controlled trial (RCT). Dr. Stone, the principal investigator of PROTECT IV, gave this presentation at the 2021 Transcatheter Cardiovascular Therapeutics (TCT) conference.

Dr. Stone begins with a succinct definition of complex and high-risk PCI (“CHIP”) patients as patients with multiple comorbidities, complex coronary artery disease that’s “not easy to revascularize in the best of circumstances”, and hemodynamic compromise. “And then you’ve got a triad of a situation where it’s hard for the interventionalist to complete, successfully, an optimal procedure in the cath lab.”

He asks, “Will MCS improve both procedural outcomes and allow the interventionalist to do a better job getting better long-term outcomes?” To answer this, he reviews the scant existing high quality randomized trial data from BCIS-1 and PROTECT II RCT, as well as observational data from the National Inpatient Sample (NIS) database, USpella registry, and PROTECT III study, highlighting the improvement in trial and registry results as best practices are developed and implemented over time.

Dr. Stone then explores why the Impella® heart pump may improve outcomes after high-risk PCI, beyond enhancing acute procedural safety. One possibility, he explains is that Impella gives operators more time to achieve complete revascularization. He reviews data from the Roma-Verona registry and RESTORE EF registry, emphasizing, “So complete revascularization really matters. And Impella gives you the time to achieve that complete revascularization in high-risk PCI in CHIP patients.” Dr. Stone also discusses the increasing evidence that Impella reduces contrast nephropathy, perhaps through improving renal blood flow during the procedure, citing data published by Michael Flaherty, MD, and data from the cVAD study.

“So, what do the guidelines say given all this information?” he asks. “Well, surprisingly, almost nothing… So, we really don’t have a lot of evidence to guide us. So, this brings us to the PROTECT IV trial, which is a major, massive undertaking.” Here’s what Dr. Stone had to say about PROTECT IV:

  • “We’ll be randomizing 1250 to 2500 patients with all sorts of coronary syndromes, with complex PCI, left main, triple vessel disease, complex lesions, who are not appropriate for surgery. And these patients will be randomized equally to the Impella CP® device versus the control, which will be either no support or balloon pump according to the operator.”
  • “Our hypothesis is that by providing hemodynamic stability during high-risk, complex PCI, Impella will facilitate improved stent optimization and more complete revascularization that will enhance not only early, but late outcomes.”
  • “We also have some incredibly important substudies about right heart catheterization, renal function with daily creatinines through 7 days, and viability substudies to determine which lesions should be revascularized with CMR at baseline and 6 months.”
  • “We’ve got about 32 patients randomized to date and hopefully within a couple years we’ll bring you the results of this important study.”

Related Content


Real World Evidence Leading to RECOVER IV

William O’Neill, MD, discusses the development of best practices for treating AMI cardiogenic shock leading to the RECOVER IV RCT.


Best Practices for Treating High-Risk PCI Patients

Jason Wollmuth, MD, discusses large-bore access and intravascular imaging best practices for treating high-risk PCI patients.


Improved Outcomes with Contemporary Practices in PROTECT III

Jeffrey Moses, MD, provides an overview of high-risk PCI clinical trials that are setting the stage for PROTECT IV RCT.

View more resources