乌鸦传媒

Coronary artery bypass grafting (CABG) still holds several clear-cut advantages over percutaneous coronary intervention (PCI), according to surgeons who revisited the data from the SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) trial.

Cardiac death due to MI was 10 times as common with PCI as with CABG among high-risk patients, noted , of Heart Hospital Baylor Plano in Texas, and colleagues in an article published online in .

There are a number of important takeaways from , the team wrote: "The incremental benefit of surgery is greater the higher the SYNTAX score, that is, the worse and more diffuse the coronary disease. For patients in the lowest SYNTAX score, the group advantages of surgery versus PCI were not statistically significant. ... It may be that PCI is an effective treatment option for those subgroups. Trials of that hypothesis in low and intermediate SYNTAX score left main disease [such as the EXCEL trial] are under way."

However, it is clear that the advantages of CABG over PCI continue to widen over time -- and the degree of revascularization achieved by either method may be to blame, Mack et al wrote.

Incomplete revascularization occurred in 43.3% of patients in the PCI arm and 36.8% of patients in the CABG arm of SYNTAX. Incomplete revascularization was tied to an increased risk for major adverse cardiac or cerebrovascular events 3 years after PCI, but incomplete revascularization in the CABG group could not be identified as a predictor for worse outcomes.

"If there is consideration of PCI for patient-related reasons, consideration of the amount of residual untreated disease that will remain after PCI is important because that adversely affects prognosis."

In an accompanying , , of Cleveland Clinic wrote: "Unlike PCI, which treats only the stenosis present at the time of revascularization, CABG treats both the current stenosis and any future stenosis that develops proximal to the distal anastomoses."

When a vessel is totally occluded or the stenosis is complex, performing PCI may be "difficult, dangerous, and even impossible, leading to incomplete revascularization and residual ischemia," whereas performing CABG in these vessels is "no more difficult than for an isolated, noncomplex stenosis."

For , and , both of Sunnybrook Health Sciences Centre in Toronto, the decision of PCI versus CABG should fall into the hands of a multidisciplinary heart team. What's more, "it behooves cardiac surgeons to adopt measures to reduce further the perioperative complications -- in particular, stroke -- and also late graft failure."

Writing in a separate in the same issue, Deb and Fremes said: "To this end, there have been advances in off-pump techniques and, more recently, a push toward arterial revascularization. As well, it is important to emphasize that the results of both PCI and CABG are enhanced by optimal medical therapy and that continuous research and advances in pharmacotherapy are therefore paramount."

Mack and colleagues noted that critics have pointed to the dated nature of the SYNTAX trial, arguing that newer-generation drug-eluting stents would have produced different results. "However, that is not the case," they wrote, citing the in which adverse events still occurred more frequently in everolimus-eluting stent recipients (15.3% versus 10.6% for CABG, P=0.004).

"Although there is a strong patient preference for a less-invasive treatment of their coronary artery disease [CAD], patients with advanced disease should be made aware that the choice of PCI puts them at increased risk of death relative to CABG, and a full and transparent discussion should occur regarding the implications of their decision."

Sabik agreed: "This review of SYNTAX confirms what we already know -- CABG is the standard of care for patients with multivessel CAD. The authors should be congratulated for continuing this discussion and advocating for patients with complex CAD to receive the best revascularization therapy."