Percutaneous coronary intervention (PCI) is associated with greater risks for long-term adverse cardiovascular events than surgery in patients with chronic total occlusion (CTO) and multivessel coronary disease, new research shows.
But among patients whose SYNTAX Score II favored PCI or demonstrated equipoise between PCI and coronary artery bypass grafting (CABG), the two strategies yielded similar risks for the primary endpoint of death, myocardial infarction (MI), or stroke at 5 years.
“CABG may still be the gold standard for patients with CTO and multivessel disease, however, state-of-the-art PCI with appropriate indication could be considered an alternative means of revascularization in the clinical setting,”
Bo Xu, MBBS, Fu Wai Hospital, Beijing, China, said at PCR e-Course 2020, the virtual meeting of the Congress of European Association of Percutaneous Cardiovascular Interventions (EuroPCR).
PCI is emerging as a possible alternative means of revascularization for CTO with multivessel disease, but no randomized trials or large registries have been designed to compare long-term outcomes, he noted. The present study, comprising 4324 consecutive patients, is thought to be the largest retrospective study to date.
“This is a very large, single-center retrospective study and as I’m saying this, already you start thinking maybe it’s not going to tell us a lot. I’d like to convince you of the opposite,” said dedicated discussant William Wijns, professor of cardiology, National University of Ireland, Galway, and codirector of EuroPCR.
Follow-up rates were extremely high, adverse events were independently adjudicated, and adjustment was made for 23 patient-level covariates in logistic regression analysis, he said.
Wijns also pointed out the sheer scale of the Fu Wai Hospital, which is equipped with 17 catheterization labs and five hybrid operating rooms, and performed about 20,000 PCIs in 2019 alone. “A good center in the West would perform 1600 PCI in a year; the [Chinese] colleagues are performing that a month.”
The study’s 2264 CABG patients and 2060 PCI patients had a CTO for at least 3 months prior to revascularization and were followed clinically at 1 month, 6 months, 1 year, and thereafter annually up to 5 years.
The CABG group was older than the PCI group, more likely to be smokers, and to have a lower ejection fraction, severely calcified lesions, lesions greater than 29 mm, and higher SYNTAX and Japanese-CTO scores.
At 30 days, all-cause mortality was comparable between the CABG and PCI groups (1.0% vs 0.4%).
The composite of death, MI, or stroke at 5 years occurred in 12.1% of patients in the CABG group and in 11.4% of the PCI group, Xu reported in a late-breaking trial session.
After inverse probability of treatment weighting, however, PCI was associated with a higher risk for the primary composite endpoint than CABG (hazard ratio [HR], 1.21; 95% confidence interval [CI], 1.02-1.44).
PCI was also linked with higher adjusted risks for all-cause mortality (HR, 1.32; 95% CI, 1.04-1.67), cardiac mortality (HR, 1.81; 95% CI, 1.31-2.49), MI (HR, 7.00; 95% CI, 4.58-10.68), and repeat revascularization (HR, 7.93; 95% CI, 6.01-10.46), but a lower risk for stroke (HR, 0.37; 95% CI, 0.25-0.54).
In subgroup analysis stratified by SYNTAX Score II, risk for the primary endpoint was similar for PCI and CABG among patients with PCI or PCI/CABG equipoise recommendations (11.1% vs 12.5%; adjusted HR, 0.94; 95% CI, 0.75-1.17).
Conversely, PCI was linked with a significantly higher risk for the primary endpoint (12.2% vs 11.5%; adjusted HR, 1.55; 95% CI, 1.14-2.09) and 5-year, all-cause mortality (5.9% vs 6.3%; adjusted HR, 1.65; 95% CI, 1.09-2.49) among patients where the SYNTAX Score II supported CABG.
In sensitivity analyses, if PCI could provide complete revascularization or reasonably incomplete revascularization — meaning a PCI residual SYNTAX Score II of 8 or less — then PCI and CABG had similar risks for the primary outcome, Xu said.
If the SYNTAX score was greater than 8, however, PCI was associated with a significantly higher risk for the primary outcome. “And even if we only compare PCI with a successful recanalization of the CTO, the overall result was not changed, still favouring CABG,” he said.
Following the presentation, session moderator Davide Capodanno, MD, PhD, University of Catania, Italy, said, “As usual, it’s all about risk when you have to decide for one procedure or another. Of course, in these very complex patients, CABG for most but maybe PCI has a role for very selected indications.”
The definition of adequate or certain PCI contains just four simple criteria but they have not been underscored in the past, Wijns observed. The emphasis has been on whether the patient has an advanced SYNTAX score for 3-vessel disease (score < 22) or left main disease (score < 33) but it’s also important to consider the criteria of whether the myocardium downstream of the CTO is viable or is causing symptoms.
“Funny enough, of all the patients who underwent PCI, only 25% of them were classified as adequate PCI according to these criteria and as much as 65% of the patients who underwent CABG actually could have been adequate for PCI,” he said. “So there is room for improvement in the selection of patients.”
“I think we can use these four criteria to help us and factor them in among the list of variables that we are looking at during the heart team discussion,” he said.
Xu and Capodanno have disclosed no relevant financial relationships. Wijns reports honorarium from Abbott Vascular, Biotronik, MicroPort, and Terumo; and grants/research support from MicroPort and Terumo.
Congress of European Association of Percutaneous Cardiovascular Interventions (EuroPCR): PCR e-Course 2020. Presented June 26, 2020.