Described as a “landmark study”, the SYNTAX trial, presented in the HOT LINE II session, is the first randomised, controlled clinical trial to compare PCI using a drug-eluting stent to CABG in patients with left main disease and three vessel disease.
All patients in the trial were assessed by a multidisciplinary team which included an interventional cardiologist and cardiac surgeon. If both felt they could offer equivalent
revascularisaton, patients were randomised in a 1:1 fashion to PCI (which used a paclitaxel-eluting coronary stent ) or CABG.
Altogether, the trial enrolled 1800 patients in its randomised arm from 62 EU sites and 23 US sites.
Results described yesterday showed that the 12-month primary endpoint rates for MACCE (Major Adverse Cardiovascular or Cerebrovascular Event rate, including all-cause death, stroke, MI and repeat revascularisation) were 17.8% for PCI and 12.1% for CABG (p=0.0015). However, outcome in the trial’s secondary endpoint (the combined rate of all-cause death, stroke and MI, with revascularisation removed) was 7.6% for PCI and 7.7% for CABG (p=0.98).
The rate of stroke, however, was 0.6% for PCI and 2.2 % for CABG (p=0.003).
Other findings from the 12-month data showed that the rate of symptomatic graft occlusion was 3.4% in the CABG group, and the rate of stent thrombosis in the PCI group 3.3% (P=0.89).
“The study failed to meet its primary endpoint for non-inferiority,” conceded investigator Patrick Serruys (Rotterdam, Netherlands), adding that the outcome was nevertheless
“hypothesis generating”. He said: “The results for the first time open the way for DES in patients with more complex anatomy and advanced disease who have traditionally been treated with CABG.”
“The good news is that both PCI and CABG have improved,” said discussant Christian Hamm (Bad Nauheim, Germany).
The “all comes” design of SYNTAX meant that patients who were not considered “eligible” for the randomised trial were enrolled into two registries, 192 to a PCI registry
and 644 to a CABG registry.
Results from the registry analysis were also presented yesterday and showed that the total MACCE rate in the PCI registry was 20.4% at 12 months, and in the CABG 8.8%.
“The registry shows that, for patients not considered eligible for CABG, PCI is a viable option,” said principal investigator Friedrich Mohr (Leipzig, Germany). “The surgical results are excellent for patients who are not candidates for PCI.”
View the complete SYNTAX presentation slides here