Unprotected left main PCI was performed less frequently compared with all other PCI, according to a study published in JAMA Cardiology.
Although infrequent, unprotected left main PCI was performed more often in patients who were older and had more comorbidities, according to the study.
“There are several possibilities to explain the limited rates of [unprotected left main] PCI in contemporary practice,” Javier A. Valle, MD, MSCS, interventional cardiologist with Rocky Mountain Veterans Affairs Medical Center and interventional cardiology fellow at University of Colorado Anschutz Medical Campus in Aurora, and colleagues wrote. “One is likely the comfort and experience that referring physicians have with CABG. Its historical efficacy and operator and institutional experience may influence referring physicians to send patients with [unprotected left main] stenosis for coronary artery bypass surgery despite data suggesting equivalent short-term and midterm outcomes in patients with lower anatomic complexity.”
Researchers analyzed data from 3,342,162 patients (mean age, 64.2 years; 67% men) from the CathPCI Registry who underwent PCI from April 2009 to July 2016. Information collected from the registry included procedural, demographic and clinical characteristics. These data were compared between patients who underwent unprotected left main PCI and those who underwent all other PCI in 2-year increments. The CathPCI risk model was used to estimate procedural risk for mortality.
The primary outcome of interest was in-hospital major adverse clinical events, defined as a composite of MI, death, stroke or emergent CABG. Assessments were also performed on individual aspects of the primary outcome.
Of the patients in the study, 33,128 underwent unprotected left main PCI. The rate of these procedures increased from 0.7% of all PCI procedures performed in the third quarter of 2015 to 1.3% in the second quarter of 2016.
Compared with patients who underwent all other PCI procedures, those who underwent unprotected left main PCI were older (71.8 years vs. 64.1 years) and had a higher burden of medical comorbidities such as HF (27.7% vs. 10%), peripheral artery disease (21.8% vs. 9.7%), cerebrovascular disease (21.6% vs. 10.6%) and diabetes (40.4% vs. 35%).
The mean annualized volume of unprotected left main PCI for operators in the registry was 0.5 procedures, and 16.7% of operators performed an average of one or more unprotected left main PCI annually. The mean annualized volume for institutions was 3.2 procedures, with 53.7% performing an average of one or more unprotected left main PCI annually.
After adjusting for covariates, patients who underwent unprotected left main PCI had greater odds of major adverse clinical events compared with those who underwent all other PCI (OR = 1.46; 95% CI, 1.39-1.53).
Comparisons with other trials
Patients from the CathPCI Registry who underwent unprotected left main PCI had more medical comorbidities and were significantly older compared with those in recent trials, according to the researchers.
“Concentrating [unprotected left main] PCI performance to experienced centers and high volume operators could potentially facilitate improved outcomes,” Valle and colleagues wrote. “Alternatively, broadening use of [unprotected left main] PCI among lower-risk patients (more similar to those seen in clinical trials) may augment operator and institutional volumes to attain operator experience and comfort among patients more likely to have successful procedures.” – by Darlene Dobkowski
Disclosures: Valle reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.