Most PCIs in US Now Done With Radial Access

The percentage of PCIs performed with radial artery access has increased substantially in the United States, but rates still lag behind those seen elsewhere in the world, registry data show.

In 2013, US operators did a little more than one in five PCIs with radial access, but nearly three in five procedures were handled with radial access in 2022, a 2.8-fold increase. In line with the randomized, controlled trials, radial access was associated with lower risks of in-hospital mortality, major access-site bleeding, and other major vascular complications.

“It’s a pretty significant shift just in a matter of 10 years: going from 20% to almost 60%,” lead investigator Reza Fazel, MD (Beth Israel Deaconess Medical Center, Boston, MA), told TCTMD. “I think that’s very encouraging, but there’s obviously still room for further growth. We’re still not caught up with Europe, Japan, and other parts of the world.”

Following a number of randomized trials showing the benefits of radial over femoral access, including MATRIX, RIVAL, RIFLE-STEACS, and others, the American College of Cardiology/American Heart Association guidelines for the management of ACS and chronic coronary artery disease say radial access should be the default access strategy (class 1 recommendation, level of evidence A) to reduce the risk of bleeding, vascular complications, and mortality. The European Society of Cardiology guidelines for the management of patients with acute and chronic coronary syndromes also strongly recommend radial access over the femoral approach when patients undergo PCI or invasive angiography.

The United Kingdom, Canada, and Japan, among others, were early adopters, with more than 90% of procedures performed in those countries done via radial access. In 2007, only 1.0% of PCIs were performed via radial access in the US, but the percentage had grown to 16.0% by 2012, according to data from the CathPCI Registry. By 2015, the percentage was greater, but femoral access was still the dominant strategy.

“In the past 15 or 20 years, there’s been a lot of interest in the benefits of radial access,” said Fazel. “There’s been at least six randomized trials, but the last one was almost 10 years ago. In parallel with this, there’s been a lot of effort to make femoral access safer, such as with ultrasound guidance, use of bivalirudin and closure devices, and so forth. So, there’s been some evolution.”

Beyond 2015, though, there are few data regarding use of radial access in the US. That led researchers to initiate the study, which was published this week in the European Heart Journal.

Better Outcomes With Radial Access

The researchers, using data from the National Cardiovascular Disease Registry (NCDR) CathPCI Registry, captured 6,658,479 PCIs performed at 1,906 US sites between January 2013 and June 2022. To look at comparative outcomes between radial and femoral access, they focused on 2,244,115 PCIs performed after April 2018, when a new version of the CathPCI Registry data collection form was available.

Between 2013 and 2022, 40% of PCIs were performed radially, increasing from 20.3% to 57.5% during this period. This represents an average absolute increase of 4.1% per year (P < 0.001 for trend). Trends were similar in patients undergoing PCI for ACS and chronic coronary disease. Among PCIs for STEMI, use of radial access increased from 13.3% to 55.6% during the study. The rise in radial PCI was seen across all US regions, but use was highest in the Northeast and Mountain regions.

Among 9,271 individual operators, the median rate of radial access was 50.6%. A little more than 5% of operators didn’t use the radial artery for any cases during the study, while 25.3% did more than 80% of PCIs via radial access.   

The adjusted rate of in-hospital mortality, which was estimated from an instrumental variable analysis, was significantly lower with radial versus femoral access (1.16% vs 1.31%; P < 0.001), as were the risks of major access-site bleeding (0.34% vs 0.98%; P < 0.001) and other vascular complications (0.12 vs 0.32; P < 0.001). In contrast, the risk of ischemic stroke was modestly, although significantly, elevated with radial versus femoral access (0.32% vs 0.27%; P < 0.001).

“There’s a very wide distribution,” said Fazel, referring to the uptake of radial PCI among individual operators. “I think it highlights the issue, when there’s that kind of variability, and the impact on outcomes is pretty clear, that there’s still a lot of room for education. One thing I suspect is that the further along folks are in their career, the harder it is to make the shift. If you’ve been doing femoral access for 30 years, the inertia is a little harder to get through.”

The goal is not for every PCI to be performed via radial access, but rates beyond 90% should be a reasonable goal, he said. There will always be cases that need to be done via the femoral artery, such as those that require mechanical support or when there are anatomical limitations, so physicians will need to maintain this skill.

Regarding the stroke finding, Fazel said there is some “physiologic plausibility” behind the small risk given the way catheters are manipulated in the innominate artery, which might embolize plaque and/or thrombus. A higher risk of stroke has not been seen in any of the randomized trials to date, although given the absolute 0.05% difference seen here, those studies would have been far too small to detect any differences. A meta-analysis published several years back hinted at a higher risk of stroke, but the finding wasn’t statistically significant, he said.

The researchers suggest that any potential risk of stroke could be mitigated by using adequate anticoagulation and by minimizing catheter manipulation with the use of long sheaths in the ascending aorta.