ORBITA-CTO

In carefully selected patients with symptomatic single-vessel chronic total occlusion, CTO PCI improved angina symptoms compared with a placebo procedure, supporting CTO PCI as a true symptom-relief intervention beyond placebo effect when performed in appropriate patients by experienced CTO operators.

Study design

  • Multicenter, randomized, blinded, placebo-controlled trial
  • First placebo-controlled trial specifically evaluating CTO PCI
  • CTO PCI vs sham/placebo procedure
  • Blinding maintained with auditory isolation, deep conscious sedation, and overnight stay
  • Antianginal medications stopped at randomization and reintroduced using a patient-initiated protocol
  • N = 50 randomized
  • Follow-up: 24 weeks

Population

  • Stable angina or angina equivalent attributed to a CTO
  • Single-vessel coronary CTO
  • No significant bystander coronary disease
  • Evidence of ischemia and viability in the CTO territory
  • J-CTO score ≤3
  • Accepted for CTO PCI by specialist CTO operator/heart team
  • Median age 64 years
  • Most patients were male

Interventions

  • CTO PCI: 25
  • Placebo procedure: 25
  • All patients underwent invasive angiography with bilateral access
  • Placebo arm underwent a sham procedure designed to mimic CTO PCI
  • Successful CTO crossing achieved in 96% of PCI patients
  • Approximately 30% of CTO PCI cases required a retrograde approach

Primary outcome

  • Angina symptom score at 24 weeks
  • Score incorporated daily angina episodes, antianginal medication use, and override events
  • CTO PCI significantly improved angina symptom score vs placebo
  • OR 4.38; 95% credible interval 1.57-12.69
  • Probability of benefit: 99.6%
  • Primary endpoint met
CTO PCI vs Placebo
Primary endpoint: improved angina symptom score at 24 weeks
5.0 3.75 2.5 1.25 0
4.38
CTO PCI
1.00
Placebo
OR 4.38 | 95% CrI 1.57-12.69
Primary endpoint: odds of improved angina symptom score at 24 weeks compared with placebo.

Secondary outcomes

  • CTO PCI produced approximately 30.6 additional angina-free days over 168 days
  • Angina frequency improved more with CTO PCI than placebo
  • Seattle Angina Questionnaire domains improved, including angina frequency, physical limitation, and quality of life
  • Physician-assessed CCS angina class improved with CTO PCI
  • No clear difference in antianginal medication use during follow-up
  • No deaths or myocardial infarctions occurred during follow-up

Safety

  • No deaths reported
  • No myocardial infarctions reported
  • No withdrawals due to worsening angina
  • One patient randomized to PCI was withdrawn during the procedure because of a complication
  • Trial was small and not powered for hard clinical safety endpoints

Interpretation

  • ORBITA-CTO shows that CTO PCI provides true placebo-adjusted angina benefit in selected patients
  • The benefit was symptomatic, not a demonstrated reduction in death or MI
  • Results apply best to symptomatic single-vessel CTO with documented ischemia/viability and J-CTO ≤3
  • Generalizability is limited by small sample size, highly selected anatomy, and experienced CTO operators
  • CTO PCI should remain a symptom-driven intervention rather than routine revascularization for all CTOs
Khan, S., Sajjad, U., Fawaz, S., et al. (2026). A randomized, placebo-controlled trial of chronic total occlusion percutaneous coronary intervention in stable angina: The ORBITA-CTO trial. Journal of the American College of Cardiology. https://doi.org/10.1016/j.jacc.2026.03.027