CClinicalTrials.gg
Sign In
RecruitingNCT06917378Updated Dec 18, 2025

TRIO CTO (Taiwan Research Initiative on Coronary Total Occlusion)

An observational study in Chronic Total Occlusion (CTO), sponsored by National Taiwan University Hospital. Recruiting at 3 sites in Taiwan. Open to participants aged 20 Years to 120 Years. Per ClinicalTrials.gov, last updated 2025-12-18.

Sponsored by National Taiwan University Hospital · Observational

From the registry’s dates

  • Started Jan 2017; still recruiting 9 years 9 months later.
Study type
Observational
Model
Case-control
Time perspective
Retrospective
Enrollment
5,000
Ages
20 Years to 120 Years
Sex
All
01

Study summary

Coronary chronic total occlusions (CTO) present a significant challenge in the field of interventional cardiology. These complex lesions, characterized by complete blockage of a coronary artery for a prolonged duration, often require specialized techniques and strategies to achieve successful revascularization.

Read the detailed description

Using this consortium, we will establish a multicenter cohort to evaluate the clinical parameters, angiographic characteristics, interventional techniques, and clinical outcomes involved in coronary CTO intervention. 3 subprojects are listed here.

Subproject 1 intends to develop a novel algorithm integrating antegrade and retrograde scoring system to optimize the CTO intervention and determine the optimal timing for primary retrograde approach. Current algorithm for CTO intervention.

Subproject 2 aims to examine the strategies and outcomes of CTO involving bifurcations. Bifurcation CTO lesions present unique challenges due to their complex anatomy. Opening of the main vessel while preserving important branches is crucial for ensuring favorable long-term clinical prognosis. This subproject will investigate different strategies and devices employed in bifurcation CTO PCI to assess their efficacy and safety outcomes.

Subproject 3 investigates the treatment strategies for right coronary artery (RCA) CTOs with concomitant left main disease, which present a unique and intricate scenario, requiring careful consideration of revascularization strategies.

02

Conditions studied

  • Chronic Total Occlusion (CTO)

Keywords

  • CTO
  • Coronary Chronic Total Occlusion
  • Coronary artery disease
  • Coronary intervention
  • Collateral channel
03

In context

Coronary Artery Disease

5,598 studies on the registry are indexed under Coronary Artery Disease; 957 are open to participants now.

This study's planned enrollment of 5,000 is above the median of 336 across 1,947 observational studies indexed under Coronary Artery Disease.

Browse Coronary Artery Disease studies →

Lead sponsor

National Taiwan University Hospital is the lead sponsor of 2,563 studies on the registry; 569 are open to participants now.

Of its 11 completed or terminated interventional studies of FDA-regulated products, 2 (18%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
20 Years to 120 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

Study population

  1. Over 20 years old
  2. Chronic total occlusion confirmed by coronary angiography, and noted for more than 3 months

Inclusion criteria

  1. Over 20 years old
  2. Chronic total occlusion confirmed by coronary angiography, and noted for more than 3 months

Exclusion criteria

Exclusion criteria Nil

05

Study design

Observational model
Case-control
Time perspective
Retrospective
Enrollment
5,000 participants (estimated)
Patient registry
No

Groups and cohorts

  • Successful CTO intervention

    Successful CTO intervention, subgrouped by strategies, ex. antegrade or retrograde approach

    Procedure: Percutaneous coronary intervention of coronary chronic total occlusion

  • Failed CTO intervention

    Failed CTO intervention, subgrouped by strategies, ex. antegrade or retrograde approach

    Procedure: Percutaneous coronary intervention of coronary chronic total occlusion

  • No CTO intervention

    CTO was not intervened

Interventions

  • ProcedurePercutaneous coronary intervention of coronary chronic total occlusion

    Coronary CTO was identified by coronary angiography, and its revascularization was attempted by either antegrade, retrograde or both approach.

    Also known as: PCI to CTO

06

What researchers measure

Primary outcomes

  1. Number of participants with technical success of CTO revascularization

    Successful CTO recanalization with \<20% residual stenosis within the treated segment and restoration of Thrombolysis in Myocardial Infarction grade 3 antegrade flow, without side branch loss

    Time frame: 1 day

  2. Number of participants with collateral channel tracking success

    retrograde guidewire crossing the CC to reach the distal cap of CTO segment.

    Time frame: 1 day

  3. Number of participants with major adverse cerebral cardiovascular events

    Death, CV death, myocardial infarction, stroke, repeat revascularization

    Time frame: 5 years

Secondary outcomes

  1. Number of participants with periprocedural myocardial infarction

    Confirmed by

    Time frame: 1 day

  2. Number of participants with periprocedural complications

    Periprocedural myocardial infarction, vessel perforation, stroke, urgent or emergent revascularization

    Time frame: 1 day

07

Study locations

3 of 3 sites recruiting
  • Chang Gung Memorial Hospital
    New Taipei City, Taiwan
    Recruiting
  • National Taiwan University Hospital
    Taipei, Taiwan
    Recruiting
  • Taipei Veterans General Hospital
    Taipei, Taiwan
    Recruiting
08

References and documents

Publications

  • Rossello X, Pujadas S, Serra A, Bajo E, Carreras F, Barros A, Cinca J, Pons-Llado G, Vaquerizo B. Assessment of Inducible Myocardial Ischemia, Quality of Life, and Functional Status After Successful Percutaneous Revascularization in Patients With Chronic Total Coronary Occlusion. Am J Cardiol. 2016 Mar 1;117(5):720-6. doi: 10.1016/j.amjcard.2015.12.001. Epub 2015 Dec 12. PubMed 26747733 ↗
  • Chen S, Karmpaliotis D, Redfors B, Shlofmitz E, Ben-Yehuda O, Crowley A, Mehdipoor G, Puskas JD, Kandzari DE, Banning AP, Morice MC, Taggart DP, Sabik JF 3rd, Serruys PW, Kappetein AP, Stone GW. Does an occluded RCA affect prognosis in patients undergoing PCI or CABG for left main coronary artery disease? Analysis from the EXCEL trial. EuroIntervention. 2019 Aug 9;15(6):e531-e538. doi: 10.4244/EIJ-D-19-00263. PubMed 31186220 ↗
  • Fefer P, Knudtson ML, Cheema AN, Galbraith PD, Osherov AB, Yalonetsky S, Gannot S, Samuel M, Weisbrod M, Bierstone D, Sparkes JD, Wright GA, Strauss BH. Current perspectives on coronary chronic total occlusions: the Canadian Multicenter Chronic Total Occlusions Registry. J Am Coll Cardiol. 2012 Mar 13;59(11):991-7. doi: 10.1016/j.jacc.2011.12.007. PubMed 22402070 ↗
  • Wu EB, Brilakis ES, Mashayekhi K, Tsuchikane E, Alaswad K, Araya M, Avran A, Azzalini L, Babunashvili AM, Bayani B, Behnes M, Bhindi R, Boudou N, Boukhris M, Bozinovic NZ, Bryniarski L, Bufe A, Buller CE, Burke MN, Buttner A, Cardoso P, Carlino M, Chen JY, Christiansen EH, Colombo A, Croce K, de Los Santos FD, de Martini T, Dens J, di Mario C, Dou K, Egred M, Elbarouni B, ElGuindy AM, Escaned J, Furkalo S, Gagnor A, Galassi AR, Garbo R, Gasparini G, Ge J, Ge L, Goel PK, Goktekin O, Gonzalo N, Grancini L, Hall A, Hanna Quesada FL, Hanratty C, Harb S, Harding SA, Hatem R, Henriques JPS, Hildick-Smith D, Hill JM, Hoye A, Jaber W, Jaffer FA, Jang Y, Jussila R, Kalnins A, Kalyanasundaram A, Kandzari DE, Kao HL, Karmpaliotis D, Kassem HH, Khatri J, Knaapen P, Kornowski R, Krestyaninov O, Kumar AVG, Lamelas PM, Lee SW, Lefevre T, Leung R, Li Y, Li Y, Lim ST, Lo S, Lombardi W, Maran A, McEntegart M, Moses J, Munawar M, Navarro A, Ngo HM, Nicholson W, Oksnes A, Olivecrona GK, Padilla L, Patel M, Pershad A, Postu M, Qian J, Quadros A, Rafeh NA, Ramunddal T, Prakasa Rao VS, Reifart N, Riley RF, Rinfret S, Saghatelyan M, Sianos G, Smith E, Spaedy A, Spratt J, Stone G, Strange JW, Tammam KO, Thompson CA, Toma A, Tremmel JA, Trinidad RS, Ungi I, Vo M, Vu VH, Walsh S, Werner G, Wojcik J, Wollmuth J, Xu B, Yamane M, Ybarra LF, Yeh RW, Zhang Q. Global Chronic Total Occlusion Crossing Algorithm: JACC State-of-the-Art Review. J Am Coll Cardiol. 2021 Aug 24;78(8):840-853. doi: 10.1016/j.jacc.2021.05.055. PubMed 34412818 ↗
  • Galassi AR, Werner GS, Boukhris M, Azzalini L, Mashayekhi K, Carlino M, Avran A, Konstantinidis NV, Grancini L, Bryniarski L, Garbo R, Bozinovic N, Gershlick AH, Rathore S, Di Mario C, Louvard Y, Reifart N, Sianos G. Percutaneous recanalisation of chronic total occlusions: 2019 consensus document from the EuroCTO Club. EuroIntervention. 2019 Jun 20;15(2):198-208. doi: 10.4244/EIJ-D-18-00826. PubMed 30636678 ↗
  • Huang CC, Lee CK, Meng SW, Hung CS, Chen YH, Lin MS, Yeh CF, Kao HL. Collateral Channel Size and Tortuosity Predict Retrograde Percutaneous Coronary Intervention Success for Chronic Total Occlusion. Circ Cardiovasc Interv. 2018 Jan;11(1):e005124. doi: 10.1161/CIRCINTERVENTIONS.117.005124. PubMed 29311284 ↗

Individual participant data

Plan to share: No

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 18, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06917378
Lead sponsor
National Taiwan University Hospital
Collaborators
Chang Gung Memorial Hospital, Taipei Veterans General Hospital, Taiwan
Responsible party
National Taiwan University Clinical Trial Center (Hsien-Li Kao, Director of Cardiovascular Center, National Taiwan University Hospital) — Principal investigator
First posted
Apr 8, 2025
Start date
Jan 1, 2017
Primary completion
Dec 31, 2034 (estimated)
Completion
Dec 31, 2034 (estimated)
Last update
Dec 18, 2025

Study contacts

Chih Fan Yeh
Contact
nicholas.yeh@gmail.com
+8862-23123456 ext. 263912
Hsien-Li Kao, MD
principal investigator · National Taiwan University Hospital

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies in this condition

Coronary Artery Disease→

Other studies from this sponsor

National Taiwan University Hospital

Start the discussion