Revascularization Volumes Halved Over 13 Years

Debra L Beck

February 19, 2020

Over the 13-year period ending in 2016, revascularization procedural volumes have dropped by half, although the percentage of percutaneous coronary intervention (PCI) procedures done for myocardial infarction (MI) have more than doubled, a new administrative study shows.

During the same period, risk-adjusted in-hospital mortality rates after coronary artery bypass grafting (CABG) have also improved, whereas in PCI for ST-segment elevation myocardial infarction (STEMI), they've hovered stubbornly around 5%.

"I actually started this study because I wanted to see whether STEMI patients who get PCI are doing better over time, and what we found was that, while the CABG cohort saw a substantial reduction in mortality by almost half, with PCI, in-hospital mortality remained about 5% over time and didn't change," said Mohamed Alkhouli, MD, the Mayo Clinic, Rochester, Minnesota.

To better understand temporal trends and outcomes of patients undergoing coronary revascularization in the United States, the researchers analyzed retrospective data from the Nationwide Inpatient Sample (NIS) database covering patients undergoing PCI or CABG from January 1, 2003 to December 31, 2016.

NIS sampling covers more than 97% of the American population, making this the largest and longest report on revascularization trends in the United States in recent years.

Researchers reported the findings of their study online February 14 in JAMA Network Open.

A total of 12,062,081 revascularization hospitalizations were identified: about 8.69 million (72.0%) PCIs and 3.37 million CABGs.

Risk-adjusted in-hospital mortality after PCI increased modestly between 2003 and 2016 for patients with STEMI, from 4.9% to 5.3% (P < .001 for trend), but mostly remained stable after PCI for non-STEMI (1.6% for both periods; = .18) or unstable angina-stable ischemic heart disease (SIHD, 0.8% to 1.0%; P < .001).

In the CABG cohort, risk-adjusted in-hospital mortality decreased significantly from 2003 to 2016, from 5.6% to 3.4% (< .001 for trend) for patients undergoing CABG in the context of AMI.

"Part of it could be that we are doing PCI in more complex patients [and the risk adjustment isn't sufficient], but it's still something that needs to be better understood and should be food for thought to better understand why we haven't been able to improve outcomes in those individuals," said editorial writer Debabrata Mukherjee, MD, Texas Tech University, El Paso.

PCI and CABG Volumes Down

The COURAGE trial was first presented in 2007 and showed that, for patients with SIHD, revascularization did not improve outcomes over optimal medical therapy. Based on the findings of this current study, it appears that message was heard loud and clear.

PCI volume decreased from 777,780 in 2003 to 440,505 in 2016, or from 366 to 180 per 100,000 American adults, a "dramatic decrease of about half, indexed to the population," said Alkhouli in an interview.

However, the percentage of PCIs done for MI more than doubled, from 22.8% in 2003 to 53.1% in 2016.

"I think it's a result of the recognition that stable patients are likely to be okay managed medically based on the COURAGE trial and other trials. The ISCHEMIA [trial] may even support a further decrease in the future and I think it will be interesting to repeat the same study in another 5 years," said Alkhouli.

Alkhouli noted that many catheterization laboratories may not be suffering from these drops in volume because of the concurrent uptick in other endovascular procedures.

"I think [the decrease] wasn't dramatically visible because of the increase in peripheral interventions and structural heart disease procedures over the years," he said. "So, the cath lab is still doing ten cases a day, or whatever, but the mix of cases has changed." He noted that other smaller studies corroborate this decrease in PCI.

Similarly, annual CABG volumes decreased from 159 to 82 per 100,000 American adults, but CABG for MI increased from 19.5% to 28.2%.

Both Alkhouli and Mukherjee told | Medscape Cardiology that they see this drop in procedures as a real win.

"I'd give the American College of Cardiology credit for coming out with appropriateness criteria to make sure that people are appropriately using things like fractional flow reserve to make sure that we are treating lesions that are truly hemodynamically significant," said Mukherjee.

He suggested that with better use of primary and secondary preventive therapies — including newer and more potent antiplatelet and antithrombic agents, PCSK9 inhibitors, and ω3 fatty acids — down the line "revascularization may be rarely indicated in those with SIHD.

Alkhouli and Mukherjee reported no conflicts of interest.

JAMA Netw Open. Published online February 14, 2020. Full text, Editorial


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: