Accuracy of the PARIS score and PCI complexity to predict ischemic events in patients treated with very thin stents in unprotected left main or coronary bifurcations

Guglielmo Gallone, Fabrizio D'Ascenzo, Federico Conrotto, Francesco Costa, Davide Capodanno, Saverio Muscoli, Alaide Chieffo, Imori Yoichi, Mauro Pennacchi, Giorgio Quadri, Ivan Nuñez-Gil, Pier Paolo Bocchino, Francesco Piroli, Ovidio De Filippo, Cristina Rolfo, Wojciech Wojakowski, Daniela Trabattoni, Zenon Huczek, Giuseppe Venuti, Andrea MontaboneAndrea Rognoni, Radoslaw Parma, Filippo Figini, Satoru Mitomo, Giacomo Boccuzzi, Alessio Mattesini, Enrico Cerrato, Wojciech Wańha, Grzegorz Smolka, Bernardo Cortese, Nicola Ryan, Mario Bo, Carlo di Mario, Ferdinando Varbella, Francesco Burzotta, Imad Sheiban, Javier Escaned, Gerard Helft, Gaetano Maria De Ferrari

Research output: Contribution to journalArticlepeer-review


Background: The PARIS risk score (PARIS-rs) and percutaneous coronary intervention complexity (PCI-c) predict clinical and procedural residual ischemic risk following PCI. Their accuracy in patients undergoing unprotected left main (ULM) or bifurcation PCI has not been assessed. Methods: The predictive performances of the PARIS-rs (categorized as low, intermediate, and high) and PCI-c (according to guideline-endorsed criteria) were evaluated in 3,002 patients undergoing ULM/bifurcation PCI with very thin strut stents. Results: After 16 (12–22) months, increasing PARIS-rs (8.8% vs. 14.1% vs. 27.4%, p <.001) and PCI-c (15.2% vs. 11%, p =.025) were associated with higher rates of major adverse cardiac events ([MACE], a composite of death, myocardial infarction [MI], and target vessel revascularization), driven by MI/death for PARIS-rs and target lesion revascularization/stent thrombosis for PCI-c (area under the curves for MACE: PARIS-rs 0.60 vs. PCI-c 0.52, p-for-difference <.001). PCI-c accuracy for MACE was higher in low-clinical-risk patients; while PARIS-rs was more accurate in low-procedural-risk patients. ≥12-month dual antiplatelet therapy (DAPT) was associated with a lower MACE rate in high PARIS-rs patients, (adjusted-hazard ratio 0.42 [95% CI: 0.22–0.83], p =.012), with no benefit in low to intermediate PARIS-rs patients. No incremental benefit with longer DAPT was observed in complex PCI. Conclusions: In the setting of ULM/bifurcation PCI, the residual ischemic risk is better predicted by a clinical risk estimator than by PCI complexity, which rather appears to reflect stent/procedure-related events. Careful procedural risk estimation is warranted in patients at low clinical risk, where PCI complexity may substantially contribute to the overall residual ischemic risk.

Original languageEnglish
JournalCatheterization and Cardiovascular Interventions
Publication statusAccepted/In press - 2020


  • bifurcation
  • dual antiplatelet therapy
  • left main
  • risk stratification

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Cardiology and Cardiovascular Medicine


Dive into the research topics of 'Accuracy of the PARIS score and PCI complexity to predict ischemic events in patients treated with very thin stents in unprotected left main or coronary bifurcations'. Together they form a unique fingerprint.

Cite this