New complication risk scores developed after wider updated analysis of data from the PROGRESS-CTO trial could help to better estimate the risks of periprocedural complications in patients undergoing chronic total occlusion (CTO) percutaneous coronary intervention (PCI), say those behind the new scores.
The study, published online Monday and in the July 25 issue of JACC: Cardiovascular Interventions, noted that while it is known that CTO PCI carries an increased risk of complications, the assessment and estimation for risk of complications is not well-defined.
“Assessment of the procedural risks and benefits is essential for patient counseling and procedural planning,” noted the authors, led by Bahadir Simsek, MD, from the Minneapolis Heart Institute.
“While several scores have been developed to assess the likelihood of technical success in CTO PCI, there are only a few tools that assess the risk of complications,” they said.
“We analyzed a large multicenter CTO PCI registry to update the previously developed PROGRESS-CTO complications score, and to develop separate risk scores for in-hospital mortality, pericardiocentesis, and acute myocardial infarction (MI).”
Simsek and colleagues developed risk scores for in-hospital major adverse cardiovascular events (MACE), mortality, pericardiocentesis, and acute MI in patients undergoing CTO PCI using data from the PROGRESS-CTO (Prospective Global Registry for the Study of Chronic Total Occlusion Intervention) trial.
PROGRESS-CTO includes data on CTO PCI procedures performed at 40 centers in the United States, Canada, Greece, Turkey, Egypt, Russia and Lebanon between 2012 and 2022. Logistic regression prediction modeling was used to identify independently associated variables before the models were internally validated with bootstrapping, said the team.
Initial analysis of data showed that among 10,487 CTO PCIs, in-hospital MACE occurred in 215 (2.05%), mortality in 47 (0.45%), pericardiocentesis in 83 (1.08%), and acute MI in 66 (0.63%). Technical success was significantly higher in patients without MACE (87% vs 66%; P < 0.001).
Patients who experienced MACE were older (age 68 vs 64; P < 0.001), more likely to be women (27% vs 19%; P = 0.004), and to have a history of heart failure (40% vs 29%; P = 0.001), a history of chronic lung disease (20% vs 14%; P = 0.032), moderate-severe calcification (67% vs 46%; P < 0.001), higher J-CTO score (2.9 vs 2.4; P < 0.001), and “lower” successful crossing with antegrade wiring (26% vs 55%; P < 0.001), said Simsek and colleagues.
“Our study identified risk factors for MACE, mortality, pericardiocentesis, and acute MI in patients undergoing CTO PCI, and created 4 internally validated risk scores and accompanying risk percentages with acceptable to excellent discrimination,” said the authors.
The final model for MACE included: ≥65 years of age (1 point), moderate-severe calcification (1 point), blunt stump (1 point), antegrade dissection and re-entry (ADR; 1 point), female (2 points) and retrograde (2 points). The final model for mortality included: ≥65 years of age (1 point), left ventricular ejection fraction ≤45% (1 point), moderate-severe calcification (1 point), ADR (1 point) and retrograde (1 point).
Meanwhile, the final model for pericardiocentesis included: ≥65 years of age (1 point), female (1 point), moderate-severe calcification (1 point), ADR (1 point) and retrograde (2 points); while the final model for acute MI included: prior coronary artery bypass graft surgery (1 point), atrial fibrillation (1 point) and blunt stump (1 point).
The C-statistics of the models were 0.74 for MACE, 0.80 for mortality, 0.78 for pericardiocentesis, and 0.72 for acute MI, Simsek and colleagues reported, noting that external validation of the newly developed scores is now needed.
‘Checks all the boxes’
Writing in an accompanying editorial, Lorenzo Azzalini, MD, PhD, MS, from the University of Washington, noted that technological developments and the systematic organization of modern techniques into procedural algorithms has allowed success rates for PCI CTO to increase over the last 10 to 15 years – with success rates up from below 70% in the past to greater than 90% more recently.
“However, an excessive emphasis on the “holy grail” of technical success (ie, aggressively using all available techniques to open the CTO during the index procedure) came at the cost of increasing complication rates,” said the editorialist, noting the initial PROGRESS-CTO complication score was developed in 2016 to estimate the risk of in-hospital MACE.
The expert said the new updates to the PROGRESS-CTO risk prediction tool, which now provides four different scores to estimate risk of MACE, mortality, tamponade requiring pericardiocentesis, and acute MI, are “most awaited.”
“What makes a risk score useful for interventional cardiologists, and CTO operators in particular? A truly relevant score must: 1) provide some meaningful information to patients and clinicians; 2) be easy to calculate; and 3) be widely applicable to all sorts of procedures and reproducible in many different practices,” said Azzalini.
“The new PROGRESS-CTO complication scores check all those boxes: they provide relevant information on the risk of life-threatening complications that the clinician can use to inform patients before the procedure, are quick and easy to calculate, have been validated in over 10,000 antegrade, retrograde, and antegrade dissection re-entry procedures, and are derived from the collective experience of several CTO operators with different degrees of experience across 4 continents.”
Simsek B, Kostantinis S, Karacsonyi J, et al. Predicting Periprocedural Complications in Chronic Total Occlusion Percutaneous Coronary Intervention: The PROGRESS-CTO Complication Scores. JACC Cardiovasc Interv 2022;15:1413-1422.
Azzalini L. The New PROGRESS-CTO Complication Scores: The Peace of Mind of Taking a Calculated Risk JACC Cardiovasc Interv 2022;15:1423-1426.
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