Original Contribution

Frequency and Outcomes of Ad Hoc Versus Planned Chronic Total Occlusion Percutaneous Coronary Intervention: Multicenter Experience

Yader Sandoval, MD1,2;  Peter Tajti, MD2,3;  Aris Karatasakis, MD4,5;  M. Nicholas Burke, MD2; Barbara A. Danek, MD4,5; Dimitri Karmpaliotis, MD, PhD6;  Khaldoon Alaswad, MD7;  Farouc A. Jaffer, MD, PhD8;  Robert W. Yeh, MD9; Mitul Patel, MD10;  Ehtisham Mahmud, MD10;  Oleg Krestyaninov, MD11;  Dmitrii Khelimskii, MD11;   James W. Choi, MD12;  Anthony H. Doing, MD13;  Catalin Toma, MD14;  R. Michael Wyman, MD15;  Barry Uretsky, MD16;   Santiago Garcia, MD17; Michalis Koutouzis, MD18;  Ioannis Tsiafoutis, MD18;  Elizabeth Holper, MD19; Jeffrey W. Moses, MD6;  Nicholas J. Lembo, MD6;  Manish Parikh, MD6;  Ajay J. Kirtane, MD6;  Ziad A. Ali, MD6;  Darshan Doshi, MD6;  David E. Kandzari, MD20;  Judit Karacsonyi, MD3,5;  Bavana V. Rangan, BDS, MPH5;  Craig Thompson, MD21;  Subhash Banerjee, MD5;  Emmanouil S. Brilakis, MD, PhD2,5


Abstract: Background. For patients needing coronary chronic total occlusion (CTO) percutaneous coronary intervention (PCI), a planned, staged intervention has been recommended by experts. Ad hoc CTO-PCI, however, occurs in practice. Methods. Observational, contemporary, multicenter, international registry. Our goals were to determine the frequency, characteristics, procedural techniques, and outcomes of patients who underwent ad hoc vs planned CTO-PCI. Results. Among 2282 patients who underwent CTO-PCI between 2012 and 2017, 318 (14%) were ad hoc. Patients undergoing ad hoc CTO-PCI had lower J-CTO, PROGRESS CTO, and PROGRESS Complications scores. Antegrade-wire escalation was used more often in ad hoc PCI (96% vs 81%; P<.001), whereas antegrade-dissection re-entry (22% vs 32%) and retrograde approaches (14% vs 38%) were more common in planned PCI (P<.001). There was no difference in ad hoc vs planned PCI in technical (85% vs 86%) and procedural success (84% vs 84%). In-hospital major adverse cardiac events (MACE) were more common in patients who underwent planned procedures (0.6% vs 2.9%; P=.02). Multivariable analyses showed that ad hoc CTO-PCI was not associated with technical success or MACE. Conclusions. Ad hoc CTO-PCI occurs more commonly in less complex lesions and is associated with similarly high success rates as planned CTO-PCI in lower J-CTO score lesions, suggesting that ad hoc CTO-PCI may be an acceptable option for experienced hybrid operators in carefully selected cases. Complex cases, as quantified by the J-CTO score, have a higher in-hospital MACE rate and should preferably be performed following proper planning and preparation.

J INVASIVE CARDIOL 2019;31(5):133-139. Epub 2019 January 15.

Key words: calcification, chronic total occlusion, high-risk PCI

Percutaneous coronary intervention (PCI) is currently performed at the same time as diagnostic angiography (ad hoc) in >80% of cases.1-3 Expert consensus recommendations suggest that ad hoc PCI is acceptable in patients with acute coronary syndromes, including both ST-segment elevation and non-ST segment elevation myocardial infarction and cardiogenic shock, and patients with simple coronary lesions that are on optimal medical therapy in whom there is evidence of inducible ischemia and appropriate consent has been obtained.1,2

For patients with higher-risk lesion(s) and complex coronary anatomy, however, such as chronic total occlusions (CTOs), a delayed (staged or planned) approach has been recommended.1,2 For patients needing CTO-PCI, a planned, staged intervention (not ad hoc) has been advocated for several reasons. First, it allows enough time for informed patient consent after discussion of the risks, benefits, goals, and alternatives (such as medical therapy or surgical revascularization) of the procedure, as well as the anticipated success rates. Second, it allows thorough procedural planning and preparation to minimize the risks and maximize the likelihood of success.4 Third, it reduces the amount of contrast and radiation dose administered to the patient in a single procedure.

We analyzed a large, international, contemporary, multicenter registry to determine the frequency, characteristics, procedural techniques, and outcomes of patients who underwent ad hoc vs planned CTO-PCI.


We examined the clinical records of patients who underwent CTO-PCI between May 2012 and February 2017 by experienced, high-volume operators at 18 CTO-PCI centers (Supplemental Appendix S1). Patients in whom information detailing whether the procedure was ad hoc vs planned was not available were excluded from analysis. Data collection was performed prospectively and retrospectively and recorded in a database (PROGRESS-CTO; ClinicalTrials.gov Identifier: NCT02061436). Some centers enrolled patients during part of the study due to participation in other studies. The study was approved by the institutional review board of each site.

Coronary CTOs were defined as coronary lesions with Thrombolysis in Myocardial Infarction (TIMI) grade 0 flow of at least 3-month duration. Estimation of the occlusion duration was based on first onset of anginal symptoms, prior history of myocardial infarction in the target-vessel territory, or comparison with a prior angiogram. Calcification was assessed by angiography as mild (spots), moderate (involving ≤50% of the reference lesion diameter), and severe (involving >50% of the reference lesion diameter). Moderate proximal vessel tortuosity was defined as the presence of at least 2 bends >70° or 1 bend >90°, and severe tortuosity as 2 bends >90° or 1 bend >120° in the CTO vessel. Interventional collaterals were defined as collaterals deemed by the operator to be amenable to crossing by a guidewire and a microcatheter. A procedure was defined as retrograde if an attempt was made to cross the lesion through a collateral vessel supplying the target vessel distal to the lesion; if not, the procedure was classified as antegrade only. Antegrade dissection/re-entry (or antegrade subintimal) was defined as antegrade PCI during which a guidewire was intentionally introduced into the subintimal space proximal to the lesion, or re-entry into the distal true lumen was attempted following intentional or inadvertent subintimal guidewire crossing.

Technical success of CTO-PCI was defined as successful CTO revascularization with achievement of <30% residual diameter stenosis within the treated segment and restoration of TIMI grade 3 antegrade flow. Procedural success was defined as achievement of technical success with no in-hospital major adverse cardiac event (MACE). In-hospital MACE included any of the following adverse events prior to hospital discharge: death, myocardial infarction, recurrent symptoms requiring urgent repeat target-vessel revascularization with PCI or coronary artery bypass graft (CABG) surgery, tamponade requiring either pericardiocentesis or surgery, and stroke. Periprocedural and late in-hospital myocardial infarctions were defined according to the Third Universal Definition of Myocardial Infarction.5 The J-CTO score was calculated as described by Morino et al,6 the PROGRESS CTO score as described by Christopoulos et al,7 and the PROGRESS Complications score as described by Danek et al.8

Statistical analyses. Categorical variables were expressed as percentages and compared using Pearson’s Chi-square test or Fisher’s exact test. Continuous variables were presented as mean ± standard deviation or median (interquartile range), and were compared using the t-test or Wilcoxon rank-sum test. Stepwise logistic regression with backward elimination was performed to determine clinical and angiographic characteristics independently associated with technical success and MACE. Variables with P<.10 on univariate analysis were included in multivariate models. All statistical analyses were performed with JMP version 13.0 (SAS Institute). Two-sided P-values of <.05 were considered statistically significant.


Among 2282 patients (2335 CTO lesions) undergoing CTO-PCI, a total of 318 (14%) were ad hoc. The baseline characteristics of the patients who underwent ad hoc vs planned CTO-PCI are shown in Table 1. The frequency of ad hoc CTO-PCI case per center ranged from 0%-73% (median, 5.9%) (Figure 1). As compared with patients who underwent planned CTO-PCI, patients who underwent ad hoc PCI were less likely to have prior CABG and prior PCI, but were more likely to have diabetes mellitus and cerebrovascular disease. Most CTO-PCIs were performed for either symptom relief (70%) or ischemia reduction (11%).

Lesion and procedural characteristics. The lesion characteristics of patients who underwent ad hoc vs planned CTO-PCI are shown in Table 2. As compared with patients undergoing planned PCI, those who underwent ad hoc PCI had lower rates of moderate/severe calcification, moderate/severe tortuosity, prior failed CTO-PCI, proximal cap ambiguity, and interventional collaterals.

Patients who underwent planned CTO-PCI had more complex lesions than those who underwent ad hoc PCI, as shown by higher J-CTO and Progress-CTO scores. Technical success varied according to J-CTO score, with success rates being similar among ad hoc and planned CTO-PCI in low J-CTO scores, but lower success rates in high J-CTO score cases that were performed ad hoc (Figure 2).

Procedural techniques and outcomes are shown in Table 3. Dual injection was performed less frequently in the ad hoc group (37% vs 71%; P<.001). Non-CTO PCI rates were higher in those undergoing ad hoc CTO-PCI vs planned CTO-PCI (47% vs 25%; P<.001). Antegrade-wire escalation was used more often in the ad hoc group (96% vs 81%; P<.001), whereas antegrade-dissection reentry (22% vs 32%) and retrograde (14% vs 38%) were more common in the planned PCI group. Patients who underwent ad hoc PCI had shorter procedural time (86 minutes vs 128 minutes; P<.001) and fluoroscopy time (29 minutes vs 47 minutes; P<.001), but larger contrast volume (270 mL vs 250 mL; P<.01), with no difference in air kerma dose (3.4 Gray vs 3.1 Gray; P=.27). There was no difference in ad hoc vs planned PCI in technical success rate (85% vs 86%; P=.60) and procedural success rate (84% vs 84%; P>.99). In-hospital MACE, however, were more common in those undergoing planned procedures (0.6% vs 2.9%; P=.02).

Multivariable analysis for technical success (Figure 3) demonstrated that bifurcation at the distal cap, prior myocardial infarction, and proximal cap ambiguity were associated with lower odds of technical success. Multivariate analysis for MACE (Figure 4) indicated that age, prophylactic mechanical support, and the use of a retrograde approach were associated with increased risk for MACE. Ad hoc PCI did not influence the likelihood of technical success (OR, 0.98; 95% CI, 0.60-1.59; P=.92) or MACE (OR, 0.39; 95% CI, 0.09-1.66; P=.20).


This study provides several insights into the frequency and outcomes of ad hoc vs planned PCI for CTO lesions. Despite expert recommendations suggesting that CTO-PCI should be performed in a planned fashion, our study demonstrates that ad hoc CTO-PCI occurs frequently (14% of all CTO-PCIs), especially in simpler lesions. Ad hoc CTO-PCI was associated with excellent technical and procedural success rates, similar to those achieved in planned procedures, particularly in patients with lower J-CTO scores. These findings suggest that experienced CTO-PCI operators may be able to successfully identify patients in whom ad hoc PCI is feasible. Furthermore, the incidence of MACE in patients undergoing ad hoc CTO-PCI was similar to non-CTO PCI (<1%) supporting appropriate patient selection.

These findings are consistent with the historical progression of coronary angioplasty and PCI, in which a gradual transition has occurred across time from early PCI requiring cardiac surgery and anesthesia on standby, to contemporary practice, in which ad hoc PCI occurs frequently, even at sites with no surgical back-up.1,2,9 In the future, it is conceivable that as the number of hybrid operators able to offer high-success and low-risk procedures increases, ad hoc CTO-PCI may be increasingly performed in select cases. Outside the United States, ad hoc CTO-PCI has been reported to occur frequently, with data from the ALKK PCI registry involving 35 interventional centers in Germany showing that ~74% of CTO-PCIs (n = 674) were performed ad hoc, albeit with a lower success rate (~68%).10 In our international multicenter registry involving 18 centers, three centers with at least 100 CTO-PCI procedures had ad hoc CTO-PCI rates exceeding 20%, ranging from 23%-73%, demonstrating that such a trend exists at present in select expert CTO-PCI centers.

Ad hoc CTO-PCI was more commonly performed in less complex lesions, but was associated with a similarly high success rate and a significantly lower complication rate as compared with planned CTO-PCI. Several questions are raised by these findings. First, while technical success rates were similar with ad hoc and planned CTO-PCI, given the lower complexity of cases who underwent ad hoc PCI, it is debatable whether higher success rates could be achieved with adequate preparation and planning. Second, the lower incidence of adverse events observed in ad hoc PCI – ie, lower in-hospital MACE rate, fewer coronary perforations, and fewer vascular access complications – is likely related to the lower complexity of these cases, as compared to planned PCI cases in which J-CTO and PROGRESS scores were significantly higher. More importantly, we demonstrate that technical success comparing ad hoc vs planned cases differs by case complexity, with low J-CTO score cases having similar technical success rates as planned procedures, but CTO-PCIs with high J-CTO scores having lower success rates when performed ad hoc. These findings suggest that ad hoc PCI may be best avoided in more complex cases.

As a result of ad hoc PCI being performed in simpler CTO lesions, the use of antegrade dissection/re-entry and retrograde crossing was higher in planned CTO-PCI cases. Dual injection (a pillar of CTO-PCI) was under-utilized in ad hoc CTO-PCI (only 37% of cases). Furthermore, compared with patients undergoing planned CTO-PCI, the incidence of non-CTO PCI was significantly higher in patients undergoing ad hoc CTO-PCI – a finding that may contribute to the higher use of contrast volume in patients undergoing ad hoc procedures, in addition to the contrast volume used for the diagnostic angiography during ad hoc cases.

Several challenges remain for performing ad hoc CTO-PCI and were not addressed by our study. First, challenges exist in regard to patient consent.11,12 Patients with suspected coronary artery disease referred to the cardiac catheterization laboratory are often quoted high procedural success rates and low complication rates on the basis of data for routine PCI; such rates, however, do not apply to CTO-PCI, which is associated with lower success rates and higher complication rates. Therefore, among the reasons to stage and plan PCI rather than proceed with an ad hoc procedure is to pause in order to discuss the distinct therapeutic alternatives, as well as both estimate and discuss procedural risks and benefits. Alternatively, it may be argued that since CTOs are common in contemporary practice,13 the consent process should also include an upfront discussion on the possibility of finding more complex anatomical lesions, such as CTOs, as well as a discussion on the potential risks, benefits, and therapies available. Second, there are logistical challenges related to procedural scheduling that may occur by performing ad hoc PCI. CTO procedures have longer procedural times in comparison to non-CTO lesions. Therefore, in cardiac catheterization laboratories with a limited number of operators and/or rooms available, it may be challenging to embark on complex procedures while other patients are waiting. For this reason, CTO operators have advocated scheduling “CTO days” in which the cardiac catheterization laboratory team/staff is prepared to proceed with planned CTO procedures.

Study limitations. Our study has several limitations. First, comparisons between the ad hoc and planned CTO-PCI groups are challenging because of significant differences in baseline characteristics. However, our goal was to examine the frequency and characteristics of patients undergoing ad hoc procedures in contemporary CTO-PCI practice. Second, this is an observational, multicenter, international, registry-based study with its intrinsic limitations. No core laboratory analysis was performed. The observed practice patterns reflect high-volume, expert operators, and may not apply to operators who are early in their learning curve for CTO-PCIs, who may benefit from thorough planning and preparation.


In a large, international, contemporary registry, ad hoc CTO-PCI was performed in 14% of cases. Ad hoc CTO-PCI was more commonly performed in less complex lesions, but was associated with similarly high success as planned CTO- PCI in lower J-CTO score lesions, suggesting that ad hoc CTO-PCI may be an acceptable option for carefully selected cases, if performed by experienced hybrid operators.

Acknowledgments. Study data were collected and managed using Research Electronic Data Capture (REDCap) electronic data capture tools hosted at the University of Texas Southwestern Medical Center in Dallas, Texas. REDCap is a secure, web-based application designed to support data capture for research studies, providing: (1) an intuitive interface for validated data entry; (2) audit trails for tracking data manipulation and export procedures; (3) automated export procedures for seamless data downloads to common statistical packages; and (4) procedures for importing data from external sources.


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From the 1Mayo Clinic, Department of Cardiovascular Diseases, Rochester, Minnesota; 2Minneapolis Heart Institute, Abbott Northwestern Hospital and Minneapolis Heart Institute Foundation, Minneapolis, Minnesota; 3University of Szeged, Division of Invasive Cardiology, Second Department of Internal Medicine and Cardiology Center, Szeged, Hungary; 4Rutgers University-New Jersey Medical School, Newark, New Jersey; 5VA North Texas Health Care System and University of Texas Southwestern Medical Center; 6Columbia University, New York, New York; 7Henry Ford Hospital, Detroit, Michigan; 8Massachusetts General Hospital, Boston, Massachusetts; 9Beth Israel Deaconess Medical Center, Boston, Massachusetts; 10VA San Diego Healthcare System and University of California San Diego, La Jolla, California; 11Meshalkin Siberian Federal Biomedical Research Center, Ministry of Health of Russian Federation, Novosibirsk, Russian Federation; 12Baylor Heart and Vascular Hospital, Dallas, Texas; 13Medical Center of the Rockies, Loveland, Colorado; 14University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania; 15Torrance Memorial Medical Center, Torrance, California; 16VA Central Arkansas Healthcare System, Little Rock, Arkansas; 17Minneapolis Healthcare System and University of Minnesota, Minneapolis, Minnesota; 18Korgialeneio-Benakeio Hellenic Red Cross General Hospital of Athens, Athens, Greece; 19The Heart Hospital Baylor Plano, Dallas, Texas; 20Piedmont Heart Institute, Atlanta, Georgia; and 21Boston Scientific, Natick, Massachusetts.

Funding: The Progress CTO registry has received support from the Abbott Northwestern Hospital Foundation. Research reported in this publication was supported by the Clinical and Translational Science Awards Program of the National Institutes of Health (Bethesda, MD, USA) under grant number UL1-RR024982. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.

PROGRESS-CTO ClinicalTrials.gov identifier: NCT02061436

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Karmpaliotis reports speakers’ bureau income from Abbott Vascular, Medtronic, and Boston Scientific. Dr Alaswad reports consultant income from Boston Scientific, Abbott Vascular, and Terumo. Dr Jaffer reports consultant income from Boston Scientific, Siemens, and Merck; non-financial research support from Abbott Vascular; research grant from National Institutes of Health (HLR01-108229). Dr Yeh reports a Career Development Award (1K23HL118138) from the National Heart, Lung, and Blood Institute. Dr Patel reports speakers’ bureau income from Astra Zeneca. Dr Mahmud reports clinical trial support from Boston Scientific, Corinudus, and Gilead; consultant income from the Medicines Company; speakers’ bureau income from Medtronic. Dr Burke reports consulting and speaker honoraria from Abbott Vascular and Boston Scientific. Dr Wyman reports honoraria/consulting/speaking fees from Boston Scientific, Abbott Vascular, and Asahi Intecc. Dr Garcia reports consultant income from Medtronic. Dr Moses reports consultant income from Boston Scientific and Abiomed. Dr Lembo reports speakers’ bureau income from Medtronic; advisory board income from Abbott Vascular and Medtronic. Dr Kirtane reports Institutional research grants from Boston Scientific, Medtronic, Abbott Vascular, Abiomed, St. Jude Medical, Vascular Dynamics, and Glaxo. Dr Ali reports grant support and consultant income from St. Jude Medical and Infraredx. Dr Parikh reports speakers’ bureau income from Abbot Vascular, Medtronic, CSI, Boston Scientific; advisory boards for Medtronic, Abbott Vascular, and Philips. Dr Rangan reports research grants from Infraredx and Spectranetics. Dr Banerjee reports research grants from Gilead and The Medicines Company; consultant/speaker honoraria from Covidien and Medtronic; ownership in MDCare Global (spouse); intellectual property in HygeiaTel. Dr Brilakis reports consulting/speaker honoraria from Abbott Vascular, Boston Scientific, CSI, Elsevier, GE Healthcare, Medicure, Infraredx, and Medtronic; research support from Regeneron and Siemens; board of directors for Cardiovascular Innovations Foundation; board of trustees for Society of Cardiovascular Angiography and Interventions. The remaining authors report no conflict of interest regarding the content herein.

Manuscript submitted November 6, 2018, and accepted November 19, 2018.

Address for correspondence: Emmanouil S. Brilakis, MD, PhD, Minneapolis Heart Institute, 920 E. 28th Street #300, Minneapolis, MN 55407. Email: esbrilakis@gmail.com