OTW balloon-facilitated antegrade true lumen puncture (OFATP): a novel simplified technique for chronic total occlusion recanalization—a case report

Abstract

Background

Achieving precise guidewire puncture into the intraplaque entry point remains a key challenge in antegrade chronic total occlusion (CTO) intervention, as not all lesions have a side branch adjacent to the entry point for real-time intravascular ultrasound guidance. This difficulty is a major contributor to subsequent haematoma expansion, intervention failure, and even complications.

Case summary

A 48-year-old man was admitted for heart failure with mildly reduced ejection fraction. Coronary angiography revealed two-vessel disease: two-segment severe stenosis of the right coronary artery (RCA) and a CTO of the proximal left anterior descending (LAD) artery. The patient declined coronary artery bypass grafting and consented to percutaneous coronary intervention. A staged approach was adopted, with RCA intervention performed first, followed by readmission for elective LAD intervention. During LAD intervention, over-the-wire balloon-assisted guidewire puncture enabled efficient antegrade guidewire crossing of the occluded segment into the distal true lumen. The patient was asymptomatic and was discharged 2 days postoperatively.

Discussion

This case highlights the potential utility of OTW balloon-facilitated antegrade true lumen puncture (OFATP) as an interventional technique in the antegrade approach.

Learning points.

• The OFATP technique may provide a feasible strategy for CTO recanalization, particularly in resource-limited settings.

• The OFATP technique may improve central puncture of the CTO proximal cap and intraplaque access.

Introduction

Chronic total occlusion (CTO) revascularization represents one of the most challenging and technically complex procedures in interventional cardiology.^1,2 Antegrade wiring (AW) represents the preferred initial strategy for most CTO lesions.^3,4 However, accurate antegrade guidewire cannulation poses a formidable challenge when no side branches are present at the occlusion ostium to facilitate intravascular ultrasound-guided wiring. Even with adjunctive strategies such as parallel wiring and tip detection–antegrade dissection re-entry (TD-ADR), reliable guidewire penetration into the true lumen remains difficult to achieve. Techniques including the BASE technique and ‘Scratch and Go’ may be used to optimize successful guidewire entry into the native vascular structure; however, these manoeuvres often result in extensive false lumen formation. False lumen expansion and intramural haematoma propagation are the primary mechanisms underlying failure of the antegrade approach. In the present case, OTW balloon-assisted antegrade puncture allowed efficient intraplaque guidewire entry into the occlusion ostium without significant haematoma. With subsequent guidewire escalation, the guidewire was successfully navigated across the CTO lesion entirely within the plaque, resulting in successful intervention.

Summary figure

First admission	Heart failure with mildly reduced ejection fraction Coronary angiography revealing two-segment severe stenosis of RCA and CTO of LAD Two drug-eluting stents implanted in two segments of the RCA
Second admission	The OFATP Technique Facilitates Antegrade Guidewire Penetration Into The Entry Point Successful Antegrade Recanalization Of Complex Long-Segment LAD CTO

Case presentation

A 48-year-old male patient was admitted with ischaemic cardiomyopathy. Echocardiography revealed left ventricular dilatation with a left ventricular ejection fraction of 45%. Coronary angiography demonstrated two-vessel coronary artery disease, including two-segment severe stenosis of the right coronary artery (RCA) and CTO of the proximal left anterior descending artery (LAD). Indications for revascularization were present. The patient declined coronary artery bypass grafting and underwent staged percutaneous coronary intervention (PCI). RCA intervention was performed first, with two drug-eluting stents implanted in the proximal and distal diseased segments, respectively.

Successful revascularization of the LAD-CTO was accomplished using the OFATP technique. Vascular access was established via the right femoral artery with a 7F sheath for left coronary catheterization, and the right radial artery with a 6F sheath for right coronary catheterization. Dual-coronary injection angiography delineated a CTO lesion in the proximal left anterior descending (LAD) artery, characterized by an absence of a tapered stump, a small side branch arising from the occlusion entry, an occlusion length of approximately 30 mm, poor distal vessel quality, and a relatively healthy landing zone in close proximity to the bifurcation (J-CTO score = 2) (Figure 1A). Multiple collateral channels originated from RCA supplying the distal LAD vasculature (Figure 1B).

Figure 1.

Coronary angiogram and IVUS evaluation of chronic total occlusion and illustration of the OFATP technique. A) CTO in the proximal LAD artery with a blunt stump and a long length of occlusion. B) Several interventional collateral channels originated from the RCA to the distal LAD. C) Final angiogram. D) Intravascular ultrasound image of the CTO entrance and proximal cap. E) Intravascular ultrasound image showing the wire positioned in the central lumen. F) Illustration of the ‘OTW balloon-facilitated antegrade true lumen puncture’ (OFATP) technique. CTO: chronic total occlusion, IVUS: Intravascular ultrasound, LAD: left anterior descending, OFATP: OTW balloon-facilitated antegrade true lumen puncture, RCA: right coronary artery.

A 2.5 × 15 mm OTW balloon (Boston Scientific, USA) was advanced to the proximal LAD, positioned as close to the CTO entry as possible over a workhorse guidewire, and inflated to nominal pressure (6 atm). Subsequently, the guidewire was exchanged for a Gaia 1st wire (ASAHI, Japan) to attempt antegrade cap puncture. Under the guidance of multiple angiographic projections and retrograde contrast injection from the contralateral RCA, the Gaia 1st wire successfully crossed the proximal CTO cap and was gently advanced distally. After traversing approximately 5 mm of the occlusive segment, the OTW balloon was withdrawn with the aid of an extension wire, and a Corsair microcatheter (ASAHI, Japan) was introduced over the guidewire. The guidewire was further manipulated, but inadvertently entered the subintimal space. A dual-lumen microcatheter was then deployed, and the parallel wire technique was performed using a Pilot 200 guidewire (Abbott, USA) in combination with a Gaia 3rd wire (ASAHI, Japan). Ultimately, the Pilot 200 guidewire was successfully navigated into the distal true LAD lumen, which was verified by contralateral coronary angiography.

Following pre-dilation with a 1.5 mm low-profile balloon, intravascular ultrasound (IVUS) imaging confirmed successful entry into the proximal true lumen, with a discrete true lumen segment measuring approximately 12 mm (Figure 1D). IVUS-guided stent implantation was subsequently performed. Four stents were implanted in a tandem fashion from the distal to the mid-proximal LAD. After high-pressure post-dilation using non-compliant balloons, a satisfactory final angiographic result was achieved (Figure 1C).

The key procedural parameters were as follows: total procedural time, 95 min; fluoroscopic time, 61 min; radiation dose, 1523 mGy; and contrast volume, 150 mL. No peri-procedural complications occurred. The patient remained asymptomatic post-procedurally and was free from major adverse cardiovascular events (MACE) throughout the 12-month follow-up period.

Discussion

In this report, we present a novel and simple technique for CTO recanalization: OTW balloon-facilitated antegrade true lumen puncture (OFATP). Currently, the AW technique remains the first-line strategy for the majority of coronary CTO recanalization procedures, owing to its relative technical simplicity and favourable safety profile.⁵ However, the success of the AW approach critically depends on precise puncture of the CTO proximal cap, which ensures that the guidewire remains confined within the vascular architecture, ideally within the plaque. The present case featured a LAD CTO with both entry and exit sites unfavourable for intraplaque navigation. The side branch near the occlusion entry was not amenable to real-time IVUS-guided antegrade wire puncture. Despite the availability of multiple interventional collateral channels for a retrograde approach, the patient’s impaired cardiac function precluded a prolonged retrograde procedure, which would have carried an increased risk of myocardial ischaemia. Importantly, given the absence of significant proximal lesions, achieving a successful central lumen puncture could improve the chances of advancing the antegrade wire into the plaque. To address these challenges, we employed the OFATP technique, which resulted in IVUS-confirmed proximal cap intraplaque puncture and facilitated antegrade revascularization of this complex LAD CTO.

Four key technical principles define the OFATP technique. First, the OTW balloon must be positioned as close as possible to the CTO entrance. Second, the proximal coronary segment should be healthy, straight, and of adequate calibre to accommodate the OTW balloon. Third, the OTW balloon diameter is selected with a balloon-to-artery ratio of 0.8–1.0 relative to the native proximal coronary artery. Fourth, after puncturing the proximal cap and advancing the guidewire several millimetres, the OTW balloon is withdrawn and exchanged for a conventional microcatheter. The choice of exchange method depends on guiding catheter size: an extension wire is used for a large OTW balloon with a ≤7F guiding catheter, whereas a trapping balloon is preferred for a small OTW balloon with an ≥8F guiding catheter.

The OFATP technique offers several advantages. First and foremost, it ensures that the guidewire is positioned and oriented toward the centre of the lumen within the 3D vessel architecture (Figure 1E). This significantly increases the likelihood of central puncture of the CTO entry point and entry into the intraplaque—a feature particularly valuable for blunt stump CTOs, as illustrated in our case. Second, OTW balloon inflation enhances overall system support and guidewire penetration force, similar to a power puncture. Third, by obstructing antegrade blood flow, balloon inflation decreases the risk of haematoma formation. Fourth, the OFATP technique allows easy conversion to other approaches, such as parallel wiring, antegrade dissection re-entry (ADR), and TD-ADR. Furthermore, we provide a brief comparison of different antegrade techniques for CTO PCI, as detailed in Supplementary Material  S1.

Several limitations should be acknowledged. First, the OFATP technique is not applicable to ostial or near-ostial CTOs, those with a major side branch adjacent to the occlusion entry, or lesions preceded by diffusely diseased or severely tortuous coronary segments. Second, careful sizing of the OTW balloon is essential to prevent overinflation-induced vascular injury, and intravascular imaging modalities such as IVUS may be beneficial in this regard. Third, further studies are needed to confirm whether the OFATP technique can shorten procedural and fluoroscopic times and enhance procedural success rates.

Conclusion

For non-tortuous CTO lesions with a sufficient non-eccentric landing zone proximal to the occlusion entry, the OFATP technique may represent an effective and straightforward alternative for antegrade guidewire puncture.

Lead author biography

Dr Maohuan Lin graduated from Sun Yat-sen University in 2006.He is currently the Deputy Director of the Coronary Heart Disease Department at Sun Yat-sen Memorial Hospital. He specializes in percutaneous coronary intervention.

Supplementary material

Supplementary material is available at European Heart Journal – Case Reports online.

Consent: The authors confirm that written informed consent was obtained from the patient for the submission and publication of this case report, in accordance with COPE guidelines.

Funding

This study was supported by grants from the National Natural Science Foundation of China (Grant No. 82570322), the Guangdong Basic and Applied Basic Research Foundation (Grant Nos. 2021A1515012042 and 2023A1515012443), the Guangzhou Science and Technology Program (Grant No. 2023A3J0699) to Prof. Maohuan Lin; the National Natural Science Foundation of China (Grant No. 82300387), the Guangzhou Science and Technology Projects (Grant No. 2024A04J4679) to Dr. Qi Guo.

Data availability

Data sharing is not applicable to this article since no datasets were generated or analyzed in this case report.