Initial Outcomes of AnteOwl IVUS-Based 3D Wiring Using the Tip Detection Method for CTO Intervention

Development and validation of a nomogram for major adverse cardiovascular events after chronic total occlusion percutaneous coronary intervention for ischemic heart failure

BACKGROUND

Chronic total occlusion percutaneous coronary intervention (CTO-PCI) is an available means of revascularization in patients with ischemic heart failure (IHF). However, the prognosis of IHF patients undergoing CTO-PCI remains unclear due to the lack of reliable clinical predictive tools.

AIM

This study aimed to establish a nomogram for major adverse cardiovascular events (MACE) after CTO-PCI in IHF patients.

METHODS

Sixty-seven potential predictive variables for MACE in 560 IHF patients undergoing CTO-PCI were screened using least absolute shrinkage and selection operator regression. A nomogram was constructed based on multivariable Cox regression to visualize the risk of MACE, and then evaluation was carried out using the concordance index (C-index), time-independent receiver operating characteristic (timeROC) curves, calibration curves, and decision curve analysis (DCA).

RESULTS

During a median follow-up of 32.0 months, there were 208 MACE occurrences. Seven variables were selected for nomogram construction: age, left ventricular ejection fraction, left ventricular end-diastolic diameter, N-terminal precursor B-type diuretic peptide, bending, and use of intravascular ultrasound and beta-blockers. The C-index was 0.715 (0.680-0.750) and the internal validation result was 0.715 (0.676-0.748). The timeROC area under the curve at 6 months, 1 year, and 2 years was 0.750 (0.653-0.846), 0.747 (0.690-0.804), and 0.753 (0.708-0.798), respectively. The calibration curves and DCA showed the nomogram had acceptable calibration and clinical applicability.

CONCLUSIONS

We developed a simple and efficient nomogram for MACE after CTO-PCI in IHF patients, which helps in early risk stratification and postoperative management optimization.

Tip Detection-Antegrade Dissection and Re-Entry With New Puncture Wire in CTO Intervention: Revolution Through 3D-Wiring

Background

The authors devised the tip detection (TD) method and developed AnteOwl WR intravascular ultrasound to standardize intravascular ultrasound-based 3-dimensional wiring for intraplaque tracking in chronic total occlusion (CTO)-percutaneous coronary intervention (PCI). The TD method also allowed antegrade dissection and re-entry (ADR). Combining TD-ADR with Conquest Pro 12 Sharpened Tip (CP12ST) wire, a new ADR wire with the strongest penetration force developed to date, enabled re-entry anywhere except calcification sites.

Objectives

This study investigated the efficacy and feasibility of TD-ADR by comparison of procedural outcomes with Stingray-ADR in CTO-PCI.

Methods

Twenty-seven consecutive CTO cases treated by TD-ADR with CP12ST wire between August 2021 and April 2023 and 27 consecutive CTO cases treated by Stingray-ADR with Conquest 8-20 (CP20) wire between March 2018 and July 2021 were retrospectively enrolled as the TD-ADR by CP12ST wire group and Stingray-ADR by CP20 wire group, respectively, from 4 facilities that could share technical information on these procedures.

Results

The success rate of the ADR procedure was significantly improved (27 of 27 cases [100%] vs 18 of 27 cases [67%], respectively; P = 0.002) and total procedural time was significantly reduced (median procedural time: 145.0 [Q1-Q3: 118.0-240.0] minutes vs 185.0 [Q1-Q3: 159.5-248.0] minutes, respectively; P = 0.028) in the TD-ADR by CP12ST wire group compared to the Stingray-ADR by CP20 wire group. There were few in-hospital major adverse cardiac and cerebrovascular events or no complications in either group.

Conclusions

TD-ADR by CP12ST wire can standardize highly accurate ADR in CTO-PCI.

Efficacy of Intravascular Ultrasound-Based 3D Wiring Using the Tip Detection Method for CTO Intervention

To perform intravascular ultrasound (IVUS)-based real-time 3-dimensional wiring in chronic total occlusion percutaneous coronary intervention, we devised a tip detection method and developed AnteOwl WR (AO)-IVUS, which is an upgraded version of Navifocus WR (Navi)-IVUS with an added pull back transducer system. We compared the procedural outcomes of AO-IVUS-based 3-dimensional wiring using the tip detection method (n = 30) and Navi-IVUS-based conventional wiring (n = 17) in chronic total occlusion percutaneous coronary intervention. The success rate of IVUS-guided wiring was markedly improved in the AO-IVUS group compared with the Navi-IVUS group (93% vs 59% of cases, respectively; P = 0.007). In cases of successful IVUS-guided wiring, the IVUS-guided wiring time was markedly improved in the AO-IVUS group compared with the Navi-IVUS group (9 ± 8 minutes vs 24 ± 26 minutes, respectively; P = 0.001). There were 2 successful cases of tip detection-antegrade dissection and re-entry in the AO-IVUS group.

Tip detection-antegrade dissection and reentry using intravascular ultrasound in chronic total occlusion intervention: first human case report

Background

It has been considered impossible to perform antegrade dissection and reentry (ADR) by simply puncturing with a guidewire using the intravascular ultrasound (IVUS) observation without the support of the Stingray system.

Case summary

A 78-year-old man suffered from effort angina pectoris due to a chronic total occlusion (CTO) lesion in the left circumflex coronary artery. A retry percutaneous coronary intervention for the CTO lesion was attempted at our hospital. The J-CTO score was 3. The first guidewire entered the subintimal space. We moved onto Stingray-ADR using the angiographic observation, but the guidewire could not be led into the true lumen. AnteOwl WR-IVUS (AO-IVUS) observation revealed a distal true lumen in which the inner lumen was maintained 5 mm beyond the CTO exit. We decided to perform the tip detection-ADR using the AO-IVUS observation. The tip detection method allowed the tip of the penetration wire to puncture the wall between the subintima and the true lumen in an exactly vertical direction, resulting in the successful creation of a reentry point. The CTO lesion was dilated with one drug-eluting stent, and normal antegrade blood flow was achieved.

Discussion

Since the tip detection method enables accurate punctures, it may allow for ADR by simply puncturing using a guidewire. Due to this method being performed using the IVUS observation, it is likely more reliable than Stingray-ADR using the angiographic observation.