PCI at Centers Without Surgical Backup ‘Probably OK,’ Nationwide Data Suggests

NEW ORLEANS, LA—Performing PCI at hospitals without surgical backup seems to be safe for a wide variety of patients, from STEMI to elective procedures, according to national registry data.

The findings should inform the long-running debate over whether centers without on-site surgery capabilities should be required to transfer patients to primary PCI centers, be permitted to solely perform primary PCI on patients who need emergent treatment, or perform all types of PCI procedures, in part to be able to maintain proficiency for emergency cases.

“This is the first real-world study showing that it's probably OK to do PCI at off-site centers,” Kashish Goel, MD (Mayo Clinic, Rochester, MN), who presented the research in a poster session yesterday at the American Heart Association Scientific Sessions 2016, told TCTMD.

This is the first real-world study showing that it's probably OK to do PCI at off-site centers. Kashish Goel

But despite the new numbers, some still harbor concerns. “From a public health perspective, I wonder if we don't have too many cath labs,” said Timothy Henry, MD (Cedars-Sinai Heart Institute, Los Angeles, CA), who was not involved in the study. “We have to be careful that as we create small-volume places that we are still able to handle the complexity.”

A Mortality Signal

The study included data from the Nationwide Inpatient Sample of almost seven million patients who received PCI in the United States between 2003 and 2012. Overall, 5.7% of the procedures were performed at centers without on-site cardiac surgery capabilities, and the proportion of these PCIs increased with time (1.8% in 2003 to 12.7% in 2013; P < 0.001 for trend).

Hospitals lacking surgical backup were more likely to perform primary PCI than those that had it (34% vs 20%; P < 0.001), rates for NSTE ACS were similar regardless (41.8% vs 42.6%), and elective PCI tended to be performed mostly at hospitals with CABG availability (24.1% vs. 38.2%). However, rates of each of these types of PCI increased over time at hospitals without on-site surgery.

In-hospital mortality was lower for patients treated at PCI centers with on-site surgery (1.4% vs. 1.9%; OR 0.74; 95% CI 0.72-0.75), but the difference disappeared after the researchers adjusted for demographics, risk factors, hospital characteristics, and procedural indication (OR 1.01; 95% CI 0.98-1.03). In subgroup analyses, patients 75 years old or younger (OR 0.94), diabetics (OR 0.94), and those with prior CABG (OR 0.83) were less likely to die in the hospital when undergoing PCI at centers with surgical backup.

From a public health perspective, I wonder if we don't have too many cath labs. Timothy Henry

Results of this study should not encourage every regional center to open a cath lab, Goel said, but these findings should be reassuring to patients, who would prefer to not be transferred long distances to high-volume centers, as this can be hard on their families.

Henry was more concerned. “PCI has become relatively safe, and so low-risk PCIs certainly you can do [at centers without surgical backup],” he said. “The problem is, even any signal for mortality is a little worrisome to me.”

For Henry, the study’s findings are “a little discouraging,” especially in terms of STEMI patients, which “need experienced centers” to be treated at. “The way for us currently to make progress in terms of the mortality with myocardial infarction is to work on out-of-hospital cardiac arrest and advanced cardiogenic shock,” he added.

Notably, annual PCI volume was equal to or less than 200 cases in almost two-thirds of the off-site surgery centers, while 81% of the on-site surgery center cases were at hospitals with annual PCI volumes of more than 400. Operator experience should play a big role as to whether a patient at a regional center without surgical backup should be transferred or not, Goel said.

“The interventional cardiologists should feel comfortable doing the procedures. Obviously [if there is] anything that makes them uncomfortable, the patient should be transferred,” he commented.

One limitation of the study, according to Goel, is the lack of data on which patients were transferred, why, and what happens to them after. Since the patients who are transferred to hospitals with on-site surgery typically are sicker or in cardiogenic shock, “it's possible that in-hospital mortality was maybe slightly underestimated at off-site centers,” he said.

“But the main message that we're giving is that [all PCI patients] are most likely safe” receiving PCI at centers without surgical capabilities, Goel concluded.