Japanese Registry Confirms PCI, CABG ‘Comparable’ for Less Complex Left Main Disease

Download this article's Factoid in PDF (& PPT for Gold Subscribers)

Coronary artery bypass graft (CABG) surgery and percutaneous coronary intervention (PCI) are both suitable for treating unprotected left main disease when lesion complexity is low or moderate. But in patients with higher Syntax scores, PCI leads to more adverse events at 3 years, according to Japanese registry data published online June 21, 2012, ahead of print in the American Journal of Cardiology.

Researchers led by Takeshi Kimura, MD, of Kyoto University (Kyoto, Japan), identified 1,005 patients with unprotected left main CAD among nearly 16,000 patients enrolled at 26 Japanese centers in the CREDO-Kyoto PCI/CABG Registry Cohort-2 from 2005 to 2007. In all, 36.3% of those with left main underwent PCI (98% receiving stents, mostly DES), and 63.7% underwent CABG. The latter group tended to have more complex coronary anatomy, higher numbers of target lesions, and more anastomoses.

At 3 years, Kaplan-Meier estimates showed that the rates of combined death/MI/stroke (primary endpoint) as well as several individual endpoints including death, cardiac death, MI, and coronary revascularization (defined as PCI or CABG for any reason) all were elevated in PCI compared with CABG patients. Stroke rates, however, were similar between the 2 groups (table 1).

Table 1. Cumulative Outcomes at 3 Years

^a Primary endpoint.

Yet when multivariable analysis was performed to adjust for differences in baseline clinical characteristics, only coronary revascularization remained higher in the PCI vs. CABG groups (HR 5.83; 95% CI 3.74-9.09; P < 0.0001).

Syntax scores were available for 932 patients (92.7%), with median scores indicating less complexity seen in the PCI vs. CABG groups (26.5 vs. 30; P < 0.0001). When patients were stratified by Syntax score into low, medium, and high categories, 3-year incidence of the primary composite was statistically similar for both interventions at the lower end of the spectrum. Patients with high Syntax scores, however, fared much worse with PCI than with CABG (table 2).

Table 2. Death/MI/Stroke Risk at 3 Years by Syntax Score

The SYNTAX trial “reported comparable safety and efficacy” for PCI and CABG in left main disease, leading to updated clinical guidelines that now regard “PCI an alternative to CABG in patients with less complex coronary anatomy or in patients with high surgical risk,” Dr. Kimura and colleagues note, stressing that SYNTAX and other randomized trials are too small to draw definitive conclusions. Such findings “should be interpreted cautiously for application to daily clinical practice because selected patients with relatively low risk profiles were generally enrolled in randomized trials. Therefore, results from large-scale observational studies are also important.”

CREDO-Kyoto registry data support to the utility of the Syntax score for risk stratification in this setting, the investigators say, advising that PCI “should be discouraged [in those with high scores] unless the operative risk is prohibitively high. In contrast, long-term clinical outcome of PCI seemed to be comparable to that of CABG in patients with a low or intermediate Syntax score, supporting the recent trend for expanding the use of PCI in this category of patients with [unprotected left main CAD].”

The ongoing EXCEL trial comparing PCI with everolimus-eluting stents vs. CABG in 2,600 patients with left main disease and Syntax scores below 33 will provide further guidance, they predict.

 

---

Source:
Shiomi H, Morimoto T, Hayano M, et al. Comparison of long-term outcome after percutaneous coronary intervention versus coronary artery bypass grafting in patients with unprotected left main coronary artery disease (from the CREDO-Kyoto PCI/CABG Registry Cohort-2). Am J Cardiol. 2012;Epub ahead of print.

 

 

Related Stories:

• PCI for Left Main Disease Uncommon in US Clinical Practice
• Long-term Safety of PCI vs. CABG for Left Main Disease Depends on Syntax Score
• Randomized Trial Clouds Debate Over DES, CABG in Left Main Disease

Click here for a listing of companies that provide support to the Cardiovascular Research Foundation, owner and operator of TCTMD.