Registry study details advancement of CTO interventions in Europe
Experienced operators in Europe are treating chronic total occlusions (CTOs) with increasing procedural success despite attempting more complex lesions over time, according to a report from the European Registry of CTO published in Circulation: Cardiovascular Interventions.
The study shows the temporal trends in practical techniques, procedural outcomes and in-hospital complications associated with CTO percutaneous coronary intervention (PCI) from 2008 through June 2015—highlighting areas of progress but also indicating room for further improvement. It contained information on 17,626 procedures performed by 53 experienced operators, all of whom have performed at least 300 CTO PCIs including 50 per year.
Procedural success increased from 79.7 percent to 89.3 percent over the study period. That metric was defined by a final residual stenosis of less than 20 percent upon visual assessment and a Thrombolysis in Myocardial Infarction flow grade of 3 after recanalization.
These gains came despite operators growing bolder; the complexity of lesions as defined by the mean J-CTO score increased from 1.76 in 2008 to 2.17 in 2015.
Senior author Georgios Sianos, MD, PhD, with AHEPA University Hospital in Thessaloniki, Greece, and colleagues credited the progress to an increased understanding of CTO PCI as well as technological innovations in guidewires and other devices.
“CTO PCI evolved for a decade and is reaching a period of standardization in terminology and practice,” the researchers wrote. “Patients with increasing comorbidities and lesion complexity are currently treated with a success rate of >90%. … CTOs are not anymore an isolated anatomic entity but the leading edge of the complex PCI field and as such should be considered and evolve further in parallel with technological evolution.”
Before recent advances, CTO PCIs comprised only a small portion of PCIs due to low rates of success compared with non-CTO PCI. That’s in spite of coronary CTOs being identified in up to 20 percent of patients with coronary artery disease, with the highest incidence among older individuals and those with diabetes or heart failure—conditions associated with a CTO prevalence exceeding 40 percent, according to the authors.
Additional findings from the European Registry of CTO include that in-hospital mortality dropped from 0.4 percent to 0.1 percent from 2008 to 2015, while the in-hospital complication rates hovered in the 4.4 percent to 5.2 percent range throughout the study period. Utilization of a retrograde approach jumped from 10.1 percent to 29.9 percent, while adoption of antegrade dissection/re-entry also improved but topped out at 5.5 percent.
Sianos et al. noted their results might not apply to less-experienced operators throughout Europe—a point echoed by the authors of a related editorial.
“Outcomes across all institutions and operators are less favorable: in an analysis from National Cardiovascular Data Registry technical success was 59%, although higher volume operators had better success and lower complication rates,” wrote Emmanouil S. Brilakis, MD, PhD, and M. Nicholas Burke, MD, both with the Minneapolis Heart Institute.
“Bridging this gap will require continued education and evolution of techniques and equipment. At present, concentrating CTO PCI (especially for more complex CTOs) to experienced operators and centers will likely provide the best outcomes.”
The editorialists said local preferences and cost may limit the uptake of antegrade dissection and re-entry, although additional training and addressing cost barriers could increase the availability of the technique and potentially improve outcomes. They believe the work by Sianos et al.—along with reports from other CTO registries—provide good benchmarks to aid clinician decision-making and discussions with patients.
However, the European analysis also leaves several unanswered questions, Burke and Brilakis said, including whether patients’ symptoms improved over the long term and how big of a gap in outcomes exists between the interventional cardiologists in this study and the rest of those on the continent.
“Fifty-three operators are not enough for all of Europe: how many other operators are at various stages of development in CTO PCI and what can be done to increase their number so that all patients in need have access to state-of-the-art CTO PCI?” Burke and Brilakis wrote.
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.