Geographic miss with aorto-ostial coronary stent implantation: insights from high-resolution coronary computed tomography angiography

The everolimus eluting Synergy MegatronTM drug-eluting stent platform: Early outcomes from the European Synergy MegatronTM Implanters' Registry

BACKGROUND

The Synergy MegatronTM is an everolimus-drug eluting stent that may offer advantages in the treatment of aorto-ostial disease and large proximal vessels.

AIMS

To report the short- to medium-term clinical outcomes from the European Synergy MegatronTM Implanters' Registry.

METHODS

This registry was an investigator-initiated study conducted at 14 European centers. The primary outcome was target lesion failure (TLF), defined as the composite of cardiovascular death, target vessel myocardial infarction (MI), and target lesion revascularisation.

RESULTS

Five hundred seventy-five patients underwent PCI with MegatronTM between 2019 and 2021. Patients were 69 ± 12 years old, 26% had diabetes mellitus, 24% had moderate-severe left ventricular impairment and 59% presented with an acute coronary syndrome. 15% were deemed prohibitively high risk for surgical revascularisation. The target vessel involved the left main stem in 55%, the ostium of the RCA in 13% and was a true bifurcation (Medina 1,1,1) in 50%.  At 1 year, TLF was observed in 40 patients, with 26 (65%) occurring within the first 30 days. The cumulative incidence of TLF was 4.5% at 30 days and 8.6% (95% CI 6.3-11.7) at 1 year. The incidence of stent thrombosis was 0.5% with no late stent thromboses. By multivariate analysis, the strongest independent predictors of TLF were severe left ventricular impairment (HR 3.43, 95% CI: 1.67-6.76, p < 0.001) and a target vessel involving the left main (HR 4.00 95% CI 1.81-10.15 p = 0.001).

CONCLUSIONS

Use of the Synergy MegatronTM everolimus eluting stent in a 'real-world' setting shows favorable outcomes at 30 days and 1 year.

Mechanisms and treatment outcomes of ostial right coronary artery in-stent restenosis

BACKGROUND

Despite a high rate of in-stent restenosis (ISR) after stenting the right coronary artery (RCA) ostium, the mechanism of ostial RCA ISR is not well understood.

AIMS

We aimed to clarify the cause of ostial RCA ISR using intravascular ultrasound (IVUS).

METHODS

Overall, 139 ostial RCA ISR lesions were identified with IVUS, pre-revascularisation. Primary ISR mechanisms were classified as follows: 1) neointimal hyperplasia (NIH); 2) neoatherosclerosis; 3) ostium not covered by the stent; 4) stent fracture or deformation; 5) stent underexpansion (old minimum stent area <4.0 mm2 or stent expansion <50%); or 6) a protruding calcified nodule.

RESULTS

The median duration from prior stenting was 1.2 (first quartile 0.6, third quartile 3.1) years. The primary mechanisms of ISR were NIH in 25% (n=35) of lesions, neoatherosclerosis in 22% (n=30), uncovered ostium in 6% (n=9) (biological cause 53%, n=74), stent fracture or deformation in 25% (n=35), underexpansion in 11% (n=15), and protruding calcified nodules in 11% (n=15) (mechanical cause 47%, n=65). Including secondary mechanisms, 51% (n=71) of ostial RCA ISRs had stent fractures that were associated with greater hinge motion of the ostial-aorta angle during the cardiac cycle. The Kaplan-Meier rate of target lesion failure at 1 year was 11.5%. When the mechanically caused ISRs were treated without new stents, they suffered a higher subsequent event rate (41.4%) compared with non-mechanical causes or mechanical causes treated without restenting (7.8%, unadjusted hazard ratio 6.44, 95% confidence interval: 2.33-17.78; p<0.0001).

CONCLUSIONS

Half of the ostial RCA ISRs were due to mechanical causes. Subsequent event rates were high, especially in mechanically caused ISRs treated without the implantation of a new stent.

The Use of Bumper Wire Technique and Intravascular Ultrasound for Precise Aorto-Ostial Stenting

Background

Aorto-ostial interventions are challenging due to the limitations of contemporary equipment, imprecise ostial demarcation, and problematic ostial lesion characteristics. Suboptimal stent placement is common and portends worse clinical outcomes. Procedural and long-term outcomes of the bumper wire technique with intravascular ultrasound (IVUS) assessment have not been investigated.

Methods

A single-center retrospective study was conducted. Patients who underwent ostial lesion percutaneous coronary intervention (PCI) with the bumper wire technique between January 2019 and September 2020 were identified. The primary endpoint was to determine the geographic miss rate defined by inadequate ostial coverage or excess stent protrusion of &gt; 2 mm by IVUS or angiography. The secondary endpoint was target lesion failure (TLF) at 6 months after PCI, defined as the composite of cardiovascular death, target vessel myocardial infarction (MI), and target lesion revascularization.

Results

In total, 45 patients were identified. The average age was 71.7 years old, and 85.4% were men. Indication for PCI was acute coronary syndrome in about a third of patients. Twenty-six patients had left main ostial lesions and 19 patients had right coronary artery ostial lesions. Geographic miss was detected in two patients (4.4%): one patient (2.2%) had excess proximal stent protrusion and one patient (2.2%) had an ostial miss. Six patients were lost to follow-up. TLF, stroke, or major bleeding were not observed in any of the patients.

Conclusion

The bumper wire technique is safe and efficient with low rates of geographic miss or adverse clinical outcomes. This is the first study to confirm precise aorto-ostial stent implantation with the bumper wire technique using IVUS confirmation.

Clinical Outcomes after Additional Dynamic Renal® Stent Implantation for Stent Recoil in Ostial Coronary Lesions

Background: Interventional treatment of aorto-ostial coronary stenoses is limited by stent recoil and suboptimal angiographic results, leading to restenosis and frequent re-interventions. As a potential bail-out strategy for stent recoil, implantation of an additional stent to increase radial force has been reported. Thus, we sought to investigate clinical outcomes after additional implantation of a Dynamic Renal^® stent (DRS), a non-coronary; bare-metal stent with very high radial force, in aorto-ostial coronary stenoses. Methods: Patients treated by implantation of DRSs for stent recoil in the ostial right coronary artery or the left main stem were identified from the hospital database. Baseline clinical and procedural characteristics were compared to patients who underwent re-intervention for in-stent-restenosis in similar segments by either implantation of conventional drug-eluting stents (DES) or paclitaxel-coated balloons (PCB). Clinical follow-ups were performed up to three years following re-intervention with the assessment of death, target lesion reintervention (TLR), and major adverse cardiac events (MACE) as a combination death, myocardial infarction and target vessel revascularization. Kaplan–Meier analyses were performed for event-free survival between the three groups. Results: Between 05/2013 and 07/2019, 28 patients underwent DRS implantation of aorto-ostial coronary lesions. In comparison with 49 patients with DES implantation and 29 patients undergoing PCB treatment, no relevant differences in baseline parameters were identified. Median follow-up was 714 days, with an available follow-up of >1 year after intervention in 82.1% of patients. In the entire study cohort at two years after re-intervention, the TLR rate was 16% (17 patients), the MACE rate 37% (39 patients), and all-cause mortality 9% (10 patients), with no significant differences between the three groups. Conclusions: DRS implantation for treating stent recoil of aorto-ostial coronary lesions resulted in a high rate of TLR, and was associated with similar risk for death and MACE compared to treatment of in-stent-restenosis with DES or PCB. Randomized, larger comparisons of contemporary DES in patients exclusively presenting with stent recoil are necessary to further define the efficacy and safety of this approach.

Optimal Fluoroscopic Projections of Coronary Ostia and Bifurcations Defined by Computed Tomographic Coronary Angiography

OBJECTIVES

The aim of this study was to define the optimal fluoroscopic viewing angles of both coronary ostia and important coronary bifurcations by using 3-dimensional multislice computed tomographic data.

BACKGROUND

Optimal fluoroscopic projections are crucial for coronary imaging and interventions. Historically, coronary fluoroscopic viewing angles were derived empirically from experienced operators.

METHODS

In this analysis, 100 consecutive patients who underwent computed tomographic coronary angiography (CTCA) for suspected coronary artery disease were studied. A CTCA-based method is described to define optimal viewing angles of both coronary ostia and important coronary bifurcations to guide percutaneous coronary interventions.

RESULTS

The average optimal viewing angle for ostial left main stenting was left anterior oblique (LAO) 37°, cranial (CRA) 22° (95% confidence interval [CI]: LAO 33° to 40°, CRA 19° to 25°) and for ostial right coronary stenting was LAO 79°, CRA 41° (95% CI: LAO 74° to 84°, CRA 37° to 45°). Estimated mean optimal viewing angles for bifurcation stenting were as follows: left main: LAO 0°, caudal (CAU) 49° (95% CI: right anterior oblique [RAO] 8° to LAO 8°, CAU 43° to 54°); left anterior descending with first diagonal branch: LAO 11°, CRA 71° (95% CI: RAO 6° to LAO 27°, CRA 66° to 77°); left circumflex bifurcation with first marginal branch: LAO 24°, CAU 33° (95% CI: LAO 15° to 33°, CAU 25° to 41°); and posterior descending artery and posterolateral branch: LAO 44°, CRA 34° (95% CI: LAO 35° to 52°, CRA 27° to 41°).

CONCLUSIONS

CTCA can suggest optimal fluoroscopic viewing angles of coronary artery ostia and bifurcations. As the frequency of use of diagnostic CTCA increases in the future, it has the potential to provide additional information for planning and guiding percutaneous coronary intervention procedures.

Clinical impact of the gap-angle ratio in patients with ostial lesions of the right coronary artery undergoing percutaneous coronary intervention

The aim of this study was to investigate the incidence of binary restenosis and its predictors in patients with ostial lesions of the right coronary artery (RCAos) who underwent percutaneous coronary intervention (PCI). RCAos are associated with a high incidence of restenosis, and the implantations of drug-eluting stents for RCAos have not been fully elucidated. The study participants included 75 patients (72.3 ± 9.5 years, 72% men) who underwent PCI for RCAos at our institution between November 2001 and May 2017. The angle between the greater curvature of the aortic wall and the right coronary artery take-off in the diastolic and systolic phases in the left anterior oblique position view was investigated. Clinical outcome was defined as binary restenosis at follow-up coronary angiography. We also evaluated target lesion failure (TLF) defined as a composite of cardiac mortality, target vessel myocardial infarction, and target lesion revascularization (TLR). The incidence of binary restenosis was 48.0% (n = 36) of the entire cohort. The incidence of TLF was 49.3% (n = 37) of the entire cohort, which was mainly driven by TLR (36.0%, n = 27). The area under the curve of the gap-angle ratio [(difference between the maximum and minimum angles)/(minimum angle); GAR] for binary restenosis was 0.73, and the cutoff value was 0.306 (sensitivity 67%, specificity 82%). The patients were divided into two groups: a low-GAR (< 0.306; n = 30) and high-GAR group (> 0.306; n = 45). Binary restenosis was more frequent in the high-GAR group than in the low-GAR group (76.7% vs. 28.9%, p = 0.007). The cumulative rate of TLF was significantly higher in the high-GAR group when compared with the low-GAR group (53.3% vs. 40.0%, p = 0.01), which was mainly driven by TLR (56.7% vs. 22.2%, p = 0.01). High-GAR (> 0.306) [OR 2.66 (1.34-5.31), p = 0.005] and stent under expansion [OR 2.37 (1.10-5.11), p = 0.03] were found to be independent predictors of binary restenosis after adjustment for multiple confounders. Multivariable analysis also revealed that high-GAR (> 0.306) [OR 2.06 (1.02-4.14), p = 0.03] and stent under expansion [OR 2.82 (1.28-6.19), p = 0.01] were independent predictors of TLF. We suggest that GAR (> 0.306) predicts binary restenosis and TLF in patients undergoing PCI for RCAos.

A 3-year experience of a simple, novel technique for accurate ostial/non-ostial coronary stenting: The buddy balloon anchor stent technique

OBJECTIVE

To evaluate the safety and efficacy of a new technique for accurate ostial/non-ostial coronary stenting in percutaneous coronary intervention (PCI).

BACKGROUND

Accurate stent localization is a key factor impacting the postoperative success of patients undergoing PCI. However, the accurate localization of some lesions, especially ostial lesions, is very difficult to achieve, because they are often complicated by bobbing or to-and-fro movement of the stent during cardiac contractions.

METHODS

We report a novel technique of precise ostial/non-ostial stenting based on the buddy balloon anchor stent (BBAS) technique. Between May 2014 and July 2017, 47 patients with significant ostial/non-ostial coronary stenosis that required accurate stenting were included in this study. Of them, 23 patients were treated using the conventional method and the remaining 24 patients were treated using (BBAS) technique. Evaluation was then performed using intravascular ultrasound (IVUS) in the procedural, or coronary computed tomography angiography (CCTA) in the follow up.

RESULTS

Using the BBAS technique, the procedural success was achieved in all 24 (100%) cases. IVUS was performed in seven patients (29.17%) and no procedural complications occurred. All six failed cases that occurred among patients with right coronary artery and left anterior descending artery ostial stenosis treated using the conventional method, the lesions were subsequently successfully re-stented using the BBAS technique. After a follow-up of 3-36 months, CCTA was performed in 11 patients (45.83%), all the stents were in the accurate position. There were no major cardiovascular events of death, myocardial infarction, or target lesion revascularization.

CONCLUSION

BBAS is a simple, highly successful and safe technique for accurate stenting of difficult ostial/nonostial coronary stenosis lesions.

GuideLiner extension catheter-facilitated side strut stenting technique for the treatment of right coronary artery ostial in-stent restenosis

Percutaneous coronary intervention (PCI) for the treatment of right coronary artery (RCA) ostial in-stent restenosis (ISR) can be challenging. The technical difficulties are compounded by excessive stent protrusion into the aorta, preventing coaxial engagement of the guiding catheter and wiring through the central stent lumen. Through this review, we aim to highlight the practical challenges encountered during the treatment of ostial RCA ISR through PCI and evaluate the various interventional techniques that have been used. We describe the first reported case of a GuideLiner extension catheter-facilitated side-strut stenting for the treatment of ostial RCA ISR and demonstrate the safety and feasibility of this novel technique.