Use of the Ostial Flash Balloon in Aorto-Ostial Chronic Total Occlusion Percutaneous Coronary Intervention
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J INVASIVE CARDIOL 2025. doi:10.25270/jic/24.00263. Epub January 13, 2025.
Abstract
Background. The use of the Ostial Flash balloon (Ostial Corporation) has received limited study in aorto-ostial chronic total occlusion (CTO) percutaneous coronary artery intervention (PCI).
Methods. The authors evaluated the outcomes of Ostial Flash balloon use in a large CTO-PCI registry (PROGRESS-CTO, NCT02061436).
Results. The Ostial Flash balloon was used in 54 of 907 aorto-ostial CTO PCIs in 905 patients (6.0%). The mean patient age was 65.1 ± 10.7 and 80.6% were men, with a high prevalence of diabetes mellitus, hypertension, prior PCI, and prior myocardial infarction. The mean occlusion length was 40.5 ± 25.1 mm, 52.2% had moderate to severe calcification, and the mean Japanese-CTO score was 2.8 ± 1.1. Lesions treated with the Ostial Flash balloon were more frequently located in the right aorto-ostium (79.6% vs 66.0%, P = .002). In the Ostial Flash group, the most common successful CTO crossing technique was antegrade wiring (46.3%), followed by the retrograde approach (40.7%); intravascular imaging was used in 61.1% of cases. Technical success (92.6% vs 87.9%, P = .300) and the incidence of major adverse cardiac events (MACE) (5.6% vs 3.6%, P = .450) was similar in the Ostial Flash vs non-Ostial Flash patients, respectively. In multivariable analysis, PCI of proximal right coronary artery CTOs was independently associated with use of the Ostial Flash balloon (odds ratio 2.2; 95% CI, 1.1-4.8; P = .036).
Conclusions. The Ostial Flash balloon is infrequently used in aorto-ostial CTO PCI. Although there were no differences in MACE with use of the balloon, randomized controlled trials are needed to determine its effectiveness.
Introduction
Aorto-ostial chronic total occlusions (CTO) originate within 3 to 5 mm from the vessel ostium1 and are often complex because of the lack of good antegrade guide support and heavy calcification.2,3 Ostial CTOs have been associated with lower technical and procedural success.2-6 Optimal stent deployment is important to avoid potential complications such as (1) incomplete stent coverage of the ostium, (2) excessive stent overhang into the aorta, (3) stent under expansion, and (4) stent deformation.7
The Ostial Flash balloon (Ostial Corporation) was designed to optimize stent implantation of aorto-ostial coronary lesions by flaring the proximal stent struts against the aortic wall.8 There is limited data on use of the Ostial Flash balloon in aorto-ostial CTO percutaneous coronary intervention (PCI).9 We examined the frequency and outcomes of Ostial Flash balloon use in aorto-ostial CTO PCI in a multicenter contemporary CTO-PCI registry.
Methods
Patient population
We analyzed the clinical and angiographic characteristics and procedural outcomes of 907 aorto-ostial CTO PCIs performed in 905 patients between 2013 and 2024 at 24 centers participating in the PROGRESS-CTO registry (Prospective Global Registry for the Study of CTO Intervention; Clinicaltrials.gov identifier: NCT02061436) registry. Cases without data on Ostial Flash balloon use and non-aorto-ostial CTOs were excluded (Figure 1).
Study data were gathered and managed using the Research Electronic Data Capture (REDCap) tools, which are maintained by the Minneapolis Heart Institute Foundation.10,11 The study was approved from the institutional review board of each participating center.
Definitions
Coronary CTOs were described as coronary lesions exhibiting a Thrombolysis In Myocardial Infarction (TIMI) grade 0 flow for a minimum duration of 3 months. The estimated duration of the occlusion was determined clinically by assessing the onset of angina, a history of myocardial infarction (MI) in the region supplied by the target artery, or by comparing with previous angiographic results. A CTO was classified as aorto-ostial if it was situated within 5 mm of the aortocoronary ostium.
Calcification was evaluated via angiography as mild (small spots), moderate (affecting ≤ 50% of the reference lesion diameter), or severe (affecting > 50% of the reference lesion diameter). Moderate tortuosity was defined as the presence of at least 2 bends greater than 70° or 1 bend exceeding 90°, while severe tortuosity was defined as 2 bends greater than 90° or 1 bend over 120° in the CTO vessel. Retrograde crossing was identified when an attempt was made to cross the lesion through a collateral vessel or bypass graft supplying the target vessel distal to the lesion. Antegrade dissection/re-entry referred to an antegrade PCI in which a guidewire was deliberately directed into the extra plaque space proximal to the lesion or when guidewire re-entry into the distal true lumen was attempted following intentional or unintentional extra plaque guidewire passage.
Technical success was defined as the successful revascularization of a CTO resulting in a residual diameter stenosis of less than 30% within the treated segment and restoration of TIMI grade 3 antegrade flow.12 Procedural success was defined as achieving technical success without any major adverse cardiac events (MACE) during the hospital stay. In‐hospital MACE included any of the following adverse events before discharge: mortality, MI, recurrent symptoms requiring urgent repeat revascularization of the target vessel through PCI or coronary artery bypass graft (CABG), tamponade needing either pericardiocentesis or surgery, and stroke. The Fourth Universal Definition of MI (type 4a MI) was used for defining MI.13
The Japanese CTO (J-CTO) score was calculated as outlined by Morino et al14 and the PROGRESS‐CTO score was calculated as described by Christopoulos et al.15 The PROGRESS‐CTO complication scores were assessed following the approach detailed by Simsek et al,16 and the PROGRESS-CTO perforation score was calculated according to the methodology provided by Konstantinis et al.17
Ostial Flash balloon
The Ostial Flash system has 2 balloons: a large, low-pressure proximal balloon for flaring the stent struts against the vessel ostium, and a smaller, high-pressure distal balloon for angioplasty. The system has 3 radio-opaque markers: the proximal marker indicates the proximal end of the anchoring balloon and should be placed in the aorta; the mid-marker shows the starting point of the angioplasty ballon and should be positioned at the vessel ostium; and the distal marker indicates the distal end of the angioplasty balloon. The Ostial Flash balloon is currently available in diameters from 3.0 to 5.0 mm and distal balloon lengths between 8 and 12 mm (Figure 2).
Statistical analysis
Categorical variables were expressed as percentages and compared using the Pearson’s chi-square test. Continuous variables were reported as mean ± SD or median (interquartile range) and were analyzed using the independent-samples t-test for normally distributed data and the Mann-Whitney U-test for non-parametric data, as appropriate. The Mann-Kendall test for monotonic trend was used to assess trend significance. The effect of the procedural characteristics on use of the Ostial Flash balloon was analyzed using univariable logistic regression, while the selection of confounders for multivariable logistic regression was guided by reasonable assumptions regarding their causal influence on device use. Minimum sample size for multivariable logistic regression was calculated with the “pmsampsize” package for R, as suggested by Riley et al.18 For new model development, events per predictor parameter level determined as 9.1; therefore, 6 parameters determined to add the analysis. The final model included the following variables: age (per 10 years), male gender, left main coronary artery and proximal right coronary artery (RCA) CTO, occlusion length (per 10 mm), and proximal cap ambiguity. Collinearity was evaluated using the variance inflation factor test, with values below 3 indicating no significant multicollinearity. The model fit was assessed using a modified Hosmer-Lemeshow goodness-of-fit test, as suggested by Nattino et al.19 All statistical analyses were conducted using R Statistical Software, version 4.3.1 (R Foundation for Statistical Computing). A 2-tailed P-value of less than 0.05 indicated statistical significance.
Results
Clinical characteristics
During the study period, the Ostial Flash balloon was used in 54 of 907 (6.0%) aorto-ostial CTO PCIs performed at 24 centers. At least 1 Ostial Flash balloon was used in 11 centers, with an overall usage rate of 8.7% among these centers. Most operators at these centers utilized the Ostial Flash balloon (Supplemental Table).
The baseline characteristics of the study population are shown in Table 1. Mean age was 65.1 ± 10.7 years and 80.6% of the patients were men, with high prevalence of diabetes mellitus, hypertension, dyslipidemia, prior PCI, prior CABG, and prior MI. The baseline characteristics of the Ostial Flash patients were similar to the non-Ostial Flash patients, except for hypertension, which was less common in Ostial Flash patients (72.2% vs 88.1%, P < .001), and baseline left ventricular ejection fraction, which was higher in Ostial Flash patients (53.5% vs 49.4%, P = .036) (Table 1).
The most common presentation was stable angina (70.9%). Preprocedural computed tomography angiography (CTA) planning was more commonly done in Ostial Flash patients (17.4% vs 7.5%, P = .025) (Table 1).
Angiographic and procedural characteristics
The primary arterial access site was most commonly femoral (87.0%) and the most common catheter size in the Ostial Flash group was 8 French (Fr) (57.4%). The femoral access site was used similarly in both groups (87.0% vs 84.5%, P = .763). The Ostial Flash group was more likely to use larger catheters (7 Fr: 38.9% vs 29.7%, 8 Fr: 57.4% vs 51.8%; P = .041) (Table 2).
The most common target vessel ostium was the right aorto-ostium (66.8%), followed by the left aorto-ostium (33.0%) and bypass graft ostium (0.2%). The mean J-CTO score of the overall study population was 2.83 ± 1.14. Mean occlusion length was 40.5 ± 25.1 mm, and 52.2% had moderate to severe calcification (Table 2).
The angiographic and procedural characteristics of the Ostial Flash patients were similar with the remaining patients, but the Ostial Flash balloon was more likely to be used in the right aorto-ostial lesions (79.6% vs 66.0%, P = .002) and in larger vessels (3.31 ± 0.60 vs 3.11 ± 0.57, P = .047) and less likely to be used in vessels with a side branch at the proximal cap (26.5% vs 50.5%, P = .001) (Table 2).
In the Ostial Flash group, the most common successful crossing strategy was antegrade wiring (46.3%), followed by retrograde wiring (40.7%) and antegrade dissection and reentry (11.1%). Intravascular imaging (IVI) was similarly used in the Ostial Flash and non-Ostial Flash groups (61.1% vs 62.1%, P = .882). (Table 3). The most common reason for IVI was stent sizing (45.6%), followed by stent optimization (44.1%) and wiring guidance (7.0%) (Figure 3A).
The average size of the Ostial Flash balloons was 4.2 ± 0.4 mm in diameter and 8.31 ± 1.1 mm in length. The most common Ostial Flash balloon sizes were 4.0 x 8 mm for right aorto-ostium lesions and 4.5 x 8 mm for left aorto-ostium lesions.
Procedural outcomes
Patients treated with the Flash Ostial balloon had similar procedure (136 [98-180] vs 135 [96-192] minutes; P = .613) and fluoroscopy (54 [33-73] vs 55 [34-82] minutes; P = .677) times and air kerma radiation doses (2.3 [1.3-3.7] vs 2.2 [1.2-3.6] Gray; P = .831) (Table 3) compared with those who did not receive the Ostial Flash. Technical (92.6% vs 87.9%, P = .300) and procedural (90.7% vs 85.8%, P = .307) success and the incidence of major cardiac adverse events (MACE) (5.6% vs 3.6%, P = .450) were similar in both groups (Figure 3B). In-hospital MACE occurred in 3 of 54 (5.6%) (Table 4) patients treated with Ostial Flash balloon: 1 (1.9%) patient died due to retroperitoneal bleeding, 1 (1.9%) patient experienced a periprocedural myocardial infarction (MI) due to side branch occlusion due to dissection of ramus intermedius, and 1 (1.9%) patient experienced an ischemic stroke.
Temporal trend of use and Flash Ostial balloon utilization predictors
Use of the Ostial Flash balloon did not change over time (P-for-trend = 0.465) (Figure 3C). In multivariable analysis, the Ostial Flash balloon was more likely to be used in proximal RCA CTOs (odds ratio 2.25; 95% CI, 1.06-4.79; P = .036; Hosmer-Lemeshow, P = .875) (Figure 3D).
Discussion
To the best of our knowledge, this is the first systematic study of Ostial Flash balloon use in aorto-ostial CTOs. The main findings were that the Ostial Flash balloon was used in 6.0% of the patients with aorto-ostial CTO and was more likely to be used in proximal right aorto-ostial CTOs.
Aorto-ostial CTOs are often found in patients with multiple comorbidities and are often complex with high prevalence of blunt/no stump, proximal cap ambiguity, and moderate to severe calcification.2,3,20 As a result, they often require retrograde crossing2,3,20(Figure 4). For PCI of aorto-ostial CTOs, it is important to evaluate whether there is a stump that can be used for antegrade crossing and whether satisfactory guide catheter support can be achieved.21 In our study, 70.1% of the patients had blunt or no stump, and lesion complexity was high (mean J-CTO score: 2.8). Similarly, Ojeda et al reported that 73.8% of patients with aorto-ostial CTOs had blunt/no stump and the mean J-CTO score was 3.1.3 As a result, the retrograde approach is frequently utilized in aorto-ostial CTOs.
Appropriate planning with angiography in multiple projections, aortography, or preprocedural CTA is important to reduce potential risks, assess calcification and the proximal cap, and select the optimal crossing strategy.7 In our study, preprocedural CTA planning was more frequently used for aorto-ostial CTO PCIs that involved use of the Flash Ostial balloon.
IVI is particularly important for stent optimization during aorto-ostial CTO PCI. Before stent implantation, IVI can identify lesion characteristics that may require plaque modification techniques, such as intravascular lithotripsy and rotational or orbital atherectomy, and can also assist in precise stent sizing.7 After stent implantation, IVI can identify inadequate stent coverage, under-expansion, ostial miss, or stent overhang into the aorta.7,22 The use of IVI has been associated with a lower risk of MACE.22 In our study, IVI was used in 61% of the Ostial Flash cases, mainly for stent sizing and stent optimization.
PCI of aorto-ostial CTOs can be challenging due to (1) difficulty or inability engaging the lesion with a guide catheter, (2) poor catheter support for antegrade crossing, (3) risk for aortocoronary dissection, (4) ostial miss due to incomplete coverage of the vessel ostium or excessive stent protrusion into the aorta resulting in higher restenosis risk, (5) stent under-expansion, (6) acute stent recoil, and (7) proximal stent deformation due to vessel size mismatch or guide manipulation.7,8,23
The Ostial Flash balloon flares the ostial stent struts against the aortic wall, reducing excessive stent protrusion into the aorta.8 Additionally, flaring the ostial struts can decrease the risk of proximal stent deformation because of vessel size mismatch or guide catheter manipulation. Stent under-expansion can lead to stent failure and target lesion revascularization.24,25 Use of the Ostial Flash balloon has been associated with larger ostial luminal area compared with standard stent implantation, which could decrease the risk of stent under-expansion and restenosis.8
In a single-center study of 13 aorto-ostial PCIs using the Ostial Flash balloon (53.9% were CTO PCIs), the technical success was 100%.8 In the same study, in-hospital MACE occurred in 1 of 13 (7.7%) patients because of femoral artery pseudoaneurysm.8 In our study in-hospital, MACE occurred in 3 of 54 (5.5%) patients (1 mortality, 1 periprocedural MI, 1 ischemic stroke).
The most common aorto-ostial CTO location is in the right aorto-ostium.1-3,20 Proximal RCA CTO was the only factor that was independently associated with use of the Flash Ostial balloon. However, the Ostial Flash balloon is not available in all cardiac catheterization laboratories, requires large diameter guide catheters, and is bulky, sometimes failing to deliver to the target lesion.
Limitations
Our study has limitations. PROGRESS-CTO is an observational study with all inherent limitations. Quantitative coronary analysis for the angiograms was not conducted, and there was no adverse event adjudication. We did not have long-term follow-up. Finally, cases were performed at experienced CTO-PCI centers, which limits the generalizability of the study’s findings to less experienced centers.
Conclusions
The Ostial Flash balloon was used in 6.0% of aorto-ostial CTO PCIs. Although there were no differences in MACE with use of the balloon, randomized controlled trials are needed to determine its effectiveness.
Affiliations and Disclosures
Deniz Mutlu, MD1; Dimitrios Strepkos, MD1; Pedro EP Carvalho, MD1; Michaella Alexandrou, MD1; Ahmed Al-Ogaili, MD1; Sandeep Jalli, MD1; Khaldoon Alaswad, MD2; Farouc A. Jaffer, MD3; Rhian Davies, DO, MS4; Paul Poommipanit, MD5; Jarrod Frizzel, MD6; Basem Elbarouni, MD7; Jaikirshan J Khatri, MD8; Sevket Gorgulu, MD9; Omer Goktekin, MD10; Ramazan Ozdemir, MD11; Mahmut Uluganyan, MD11; Ahmed ElGuindy, MD12; Yasser Sadek, MD13; Yousif Ahmed, BMedSci, BMBS, PhD14; Mir B. Basir MD2; Leah Raj, MD15; Luiz Ybarra, MD, PhD16; Bilal Murad MD1; Bavana V. Rangan, BDS, MPH1; Olga C. Mastrodemos, BA1; Lorenzo Azzalini MD, PhD, MSc17; Yader Sandoval, MD1; M. Nicholas Burke, MD1; Emmanouil S. Brilakis, MD, PhD1
From the 1Minneapolis Heart Institute and Minneapolis Heart Institute Foundation, Abbott Northwestern Hospital, Minneapolis, Minnesota; 2Henry Ford Cardiovascular Division, Detroit, Michigan; 3Massachusetts General Hospital, Boston, Massachusetts; 4WellSpan York Hospital, York, Pennsylvania; 5University Hospitals, Case Western Reserve University, Cleveland, Ohio; 6The Christ Hospital, Cincinnati, Ohio; 7St. Boniface General Hospital, Winnipeg, Manitoba, Canada; 8Cleveland Clinic, Cleveland, Ohio; 9Biruni University Medical School, Istanbul, Turkey; 10Memorial Bahcelievler Hospital, Istanbul, Turkey; 11Bezmialem Vakif University, Istanbul, Turkey; 12Aswan Heart Center, Magdi Yacoub Foundation, Egypt; 13National Heart Center, Cairo, Egypt; 14Yale University, New Haven Hospital, New Haven, Connecticut; 15Vanderbilt University, Nashville, Tennessee; 16Western University, London, Ontario, Canada; 17University of Washington, Seattle, Washington.
Acknowledgments
The authors are grateful for the philanthropic support of our generous anonymous donors (2), and the philanthropic support of Drs. Mary Ann and Donald A Sens; Mrs. Diane and Dr. Cline Hickok; Mrs. Wilma and Mr. Dale Johnson; Mrs. Charlotte and Mr. Jerry Golinvaux Family Fund; the Roehl Family Foundation; the Joseph Durda Foundation; Ms. Marilyn and Mr. William Ryerse; Mr. Greg and Mrs. Rhoda Olsen. The generous gifts of these donors to the Minneapolis Heart Institute Foundation’s Science Center for Coronary Artery Disease (CCAD) helped support this research project.
Disclosures: Dr Alaswad receives consulting/speaker honoraria from Boston Scientific, Abbott Vascular, Teleflex, and CSI. Dr Jaffer receives consulting/speaker honoraria from Canon, Biotronik, Teleflex, Boston Scientific, Heartflow, Siemens, and Mercator; and is a shareholder in Fastwave, DurVena, and Intravascular Imaging, Inc. Dr Davies receives speaker honoraria from Abiomed, Asahi Intec, Boston Scientific, Medtronic, Siemens Healthineers, Shockwave, and Teleflex; and serves on the advisory boards of Abiomed, Boston Scientific, Medtronic, and Rampart. Dr Poommipanit receives consulting honoraria from Medtronic, Asahi Intecc, and Abbott Vascular. Dr Khatri receives personal honoraria for proctoring and speaking from Abbott Vascular, Medtronic, Terumo, Shockwave, and Boston Scientific. Dr. Gorgulu receives consulting/speaker honoraria from APT medical, Translumina Therapeutics, RSR medical, Tepa Saglik. Dr Basir receives consulting/speaker honoraria from Abiomed, Boston Scientific, Chiesi, Saranas, and Zoll. Dr Azzalini receives consulting/speaker honoraria from Abbott, Teleflex, GE Healthcare, Reflow Medical, Cardiovascular Systems Inc, and Abiomed; and serves on the advisory boards of Abiomed and GE Healthcare. Dr Sandoval receives consulting/speaker honoraria from Abbott Diagnostics, Roche Diagnostics, Zoll, Philips, CathWorks, HeartFlow, and Cleerly; is an associate editor of JACC Advances; and holds patent 20210401347. Dr Burke receives consulting honoraria and has received speaker honoraria from Abbott Vascular and Boston Scientific. Dr Brilakis receives consulting/speaker honoraria from Abbott Vascular, the American Heart Association (associate editor, Circulation), Biotronik, Boston Scientific, Cardiovascular Innovations Foundation (Board of Directors), Cordis, CSI, Elsevier, GE Healthcare, Haemonetics, IMDS, Medtronic, and Teleflex; receives research support from Boston Scientific and GE Healthcare; is the owner of Hippocrates LLC; and is a shareholder in MHI Ventures, Cleerly Health, Stallion Medical, and TrueVue, Inc. The remaining authors report no financial relationships or conflicts of interest regarding the content herein.
Address for correspondence: Emmanouil S. Brilakis, MD, PhD, Minneapolis Heart Institute, 920 E 28th Street #300, Minneapolis, MN 55407, USA. Email: esbrilakis@gmail.com; X: @dnzmtlu, @CCAD_MHIF, @LAzzaliniMD, @yadersandoval, @esbrilakis
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