乌鸦传媒

Even among high-volume cardiovascular interventionalists, more experience was tied to better outcomes of stenting the left main coronary artery, data from a Chinese hospital showed.

After accounting for several differences between groups, among patients whose left main percutaneous coronary intervention (PCI) was performed by an "experienced" interventional cardiologist performing at least 15 such cases per year for at least 3 years in a row, compared with their peers who saw a less experienced operator averaging only 12 left main cases annually.

This difference held up both at 30-day follow-up (0.5% versus 2.1%, adjusted HR 0.22, 95% CI 0.09-0.59) and at 3 years (2.5% versus 4.6%, adjusted HR 0.49, 95% CI 0.29-0.84).

Furthermore, there was a trend towards a decreased risk of stent thrombosis with high-volume operators at 30 days (0.4% versus 1.1%, adjusted HR 0.34, 95% CI 0.11-1.06), , of Fu Wai Hospital in Beijing, and colleagues reported online in .

"Our study has potentially important clinical implications. It is the first study to conclusively show that operator experience affects prognosis after high-risk PCI, in this case left main PCI," they wrote.

"This is an important finding because the impact of operator experience on outcomes after mainstream (simple) PCI is a matter of active debate. Some PCI procedures are more technically demanding than others ... It is likely that operator experience has a greater influence on the outcomes of complex PCI procedures than more simple procedures."

Moreover, Gao's group showed that operator experience was important regardless of stent number, lesion location (proximal versus distal), and intravascular ultrasound use.

"Incorporating operator experience and volume in an already validated stratification model such as the SYNTAX score and the SYNTAX score II improved the discrimination capability of these score algorithms," the authors added.

The investigation included 1,948 consecutive patients who underwent unprotected left main PCI at Fu Wai Hospital between 2004 and 2011 done by 25 operators.

The 28% of operators called experienced in the study -- doing at least 15 left main PCIs per year for at least 3 consecutive years -- performed the majority (73%) of left main PCIs in Gao's study. The patients they saw tended to have more complex and extensive coronary artery disease.

As for the limitations of the single-center study, Gao's group listed its retrospective nature and the low event rate observed.

And can these results be generalized to practice in other countries?

The U.S. paints a very different picture of what constitutes an "experienced" left main PCI operator, according to , of the University of California San Francisco, and , of Baylor Scott & White Health in Temple, Texas.

Based on National Cardiovascular Data Registry (NCDR) data, the average operator only performed two such procedures, they wrote in their accompanying editorial.

"Using the same criteria for low- and high-volume operators as Xu et al., 86% of the NCDR operators performed 4 or fewer unprotected left main coronary artery PCIs annually, and only 1% of NCDR operators performed ≥15 [left main] PCIs per year. The high-volume NCDR operators performed 709 of the 8,420 annual [left main] PCI procedures in the United States (8.4%)."

"These numbers are a stark contrast compared with the experience reported by Xu et al. and perhaps should be a wake-up call to the interventional community," Brindis and Dehmer wrote, calling the concept of the center of excellence "frankly overused to the point that it now has little meaning."

"If the interventional community follows the lead of Xu et al., a 'center of excellence' for [left main] PCI should be one with experienced, high-volume operators that can show good outcomes. The NCDR data demonstrate some evidence of a modest pattern of selective referral to high-volume operators, but clearly the vast majority of these procedures are performed by low-volume operators."