Clinical Outcomes in Patients Treated With Biodegradable-Polymer Biolimus-Eluting Stents and 6 Months of Dual-Antiplatelet Therapy: The French eBiomatrix 6-Month DAPT Registry

BACKGROUND

Dual-antiplatelet treatment (DAPT) has conventionally been prescribed for 1 year after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation. Recent evidence suggests that a duration of only 6 months may be equally safe and effective when using contemporary DES options.

OBJECTIVE

The aim of this study was to assess clinical outcomes in patients treated with the BioMatrix biodegradable-polymer coated biolimus-eluting stent (BP-BES; Biosensors International) who received only 6 months of DAPT.

METHODS

This prospective "all-comers" registry enrolled 2038 patients in France. Following PCI, DAPT was started for a recommended period of 6 months. Patients were followed up at 6 and 24 months. The primary endpoint of major adverse cardiac and cerebrovascular event (MACCE) was a composite of all-cause death, cerebrovascular accidents, non-fatal myocardial infarction, or clinically driven target-vessel revascularization. Secondary endpoints included stent thrombosis (ST) and major bleeding (MB).

RESULTS

The mean age of the study population was 67 ± 10.5 years and 77% of patients were male. Follow-up data were available in 96.9% and 95.3% of patients at 6 and 24 months, respectively. At 6 months, the incidences of MACCE, ST, and MB were 3.1%, 0.3%, and 0.4%, respectively. At 24 months, 21.2% of patients were still on DAPT and the cumulative incidences of MACCE, ST, and MB were 9.7%, 0.54%, and 0.79%, respectively.

CONCLUSIONS

In this unselected population of patients undergoing PCI with a BP-BES, a 6-month duration of DAPT after implantation is safe and effective.

Predicting the Need For Permanent Pacing After Implantation of the Repositionable Lotus Transcatheter Aortic Valve

BACKGROUND

The need for permanent pacemaker implantation (PPI) following transcatheter aortic valve implantation (TAVI) is a recognized complication due to compression of the cardiac conduction system. PPI rates vary according to type of TAVI device, implantation technique, and patient-related factors.

METHODS

We analyzed the baseline characteristics, and then the preprocedure and daily postprocedure electrocardiograms (ECGs) of 101 consecutive patients who underwent TAVI using the Lotus valve (Boston Scientific) between 2013 and 2015.

RESULTS

Mean patient age was 81.7 ± 7.7 years, 56% were male. and 21 patients were excluded because of baseline atrial fibrillation or a pre-existing PPI. Of the remaining 80 patients, a total of 28 (35%) underwent PPI at a mean 2.7 days after TAVI. There were no differences in development of new left bundle-branch block between the two groups (65% PPI group vs 74% no-PPI group; P=.37). The initial PR interval did not differ between groups (183 ms PPI group vs 184 ms no-PPI group). The PR interval increased by day 1 post procedure (232 ms PPI group vs 195 ms no-PPI group; P<.01) and day 2 (267 ms PPI group vs 211 ms no-PPI group; P<.05).

CONCLUSIONS

Patients with a PR interval ≤230 ms on day 1 or ≤260 ms on day 2 post TAVI using the Lotus device are at very low risk of requiring PPI, irrespective of the presence of left bundle-branch block, and can be safely discharged without prolonged monitoring.

Automatic segmentation of optical coherence tomography pullbacks of coronary arteries treated with bioresorbable vascular scaffolds: Application to hemodynamics modeling

Background / Objectives

Automatic algorithms for stent struts segmentation in optical coherence tomography (OCT) images of coronary arteries have been developed over the years, particularly with application on metallic stents. The aim of this study is three-fold: (1) to develop and to validate a segmentation algorithm for the detection of both lumen contours and polymeric bioresorbable scaffold struts from 8-bit OCT images, (2) to develop a method for automatic OCT pullback quality assessment, and (3) to demonstrate the applicability of the segmentation algorithm for the creation of patient-specific stented coronary artery for local hemodynamics analysis.

Methods

The proposed OCT segmentation algorithm comprises four steps: (1) image pre-processing, (2) lumen segmentation, (3) stent struts segmentation, (4) strut-based lumen correction. This segmentation process is then followed by an automatic OCT pullback image quality assessment. This method classifies the OCT pullback image quality as ‘good’ or ‘poor’ based on the number of regions detected by the stent segmentation. The segmentation algorithm was validated against manual segmentation of 1150 images obtained from 23 in vivo OCT pullbacks.

Results

When considering the entire set of OCT pullbacks, lumen segmentation showed results comparable with manual segmentation and with previous studies (sensitivity ~97%, specificity ~99%), while stent segmentation showed poorer results compared to manual segmentation (sensitivity ~63%, precision ~83%). The OCT pullback quality assessment algorithm classified 7 pullbacks as ‘poor’ quality cases. When considering only the ‘good’ classified cases, the performance indexes of the scaffold segmentation were higher (sensitivity >76%, precision >86%).

Conclusions

This study proposes a segmentation algorithm for the detection of lumen contours and stent struts in low quality OCT images of patients treated with polymeric bioresorbable scaffolds. The segmentation results were successfully used for the reconstruction of one coronary artery model that included a bioresorbable scaffold geometry for computational fluid dynamics analysis.

The effect of elective implantation of the ABSORB bioresorbable vascular scaffold on coronary microcirculation: Serial assessment using the index of microcirculatory resistance

INTRODUCTION

Stenting with metal stents can affect microcirculatory function. The impact of BVS on the microvascular network has not been studied.

METHODS

A total of 30 patients with bifurcation disease of Medina (X,X,0) scheduled for elective PCI with the ABSORB BVS were studied. Pressure wire studies were performed before and after scaffold implantation and at a mean follow-up of 9 months. At each time point, FFR, IMR, and CFR were calculated using the thermodilution method.

RESULTS

Following scaffold implantation, FFR change from pre-PCI, post-PCI and follow-up was 0.76, 0.92 and 0.91, respectively (P < 0.001 from pre to post-PCI and P = 0.91 from post-PCI to follow-up). There was a statistically significant improvement between pre- and post-procedural IMR (median 27.7 to 17.9, P = 0.02) and CFR (median 2.2 to 2.9, P = 0.02). Median IMR at follow-up (23.6) remained numerically lower than pre-procedure but this was not statistically significant (P = 0.05). Similarly, while median CFR at follow-up remained at post-procedural level (2.9), this effect did not reach statistical significance (P = 0.06).

CONCLUSION

There is an immediate reduction in microvascular resistance after elective BVS implantation but this effect is not sustained long term.

Initial experience of a large, self-expanding, and fully recapturable transcatheter aortic valve: The UK & Ireland Implanters' registry

OBJECTIVES

The UK & Ireland Implanters' registry is a multicenter registry which reports on real-world experience with novel transcatheter heart valves.

BACKGROUND

The 34 mm Evolut R transcatheter aortic valve is a self-expanding and fully recapturable transcatheter aortic valve, designed to treat patients with a large aortic annulus.

METHODS

Between January 2017 and April 2018, clinical, procedural and 30-day outcome data were prospectively collected from all patients receiving the 34 mm Evolut R valve across 17 participating centers in the United Kingdom and Ireland. The primary efficacy outcome was the Valve Academic Research Consortium-2(VARC-2)-defined endpoint of device success. The primary safety outcome was the VARC-2-defined composite endpoint of early safety at 30 days.

RESULTS

A total of 217 patients underwent attempted implant. Mean age was 79.5 ± 8.8 years and Society of Thoracic Surgeons Predicted Risk of Mortality Score 5.2% ± 3.4%. Iliofemoral access was used in 91.2% of patients. Device success was 79.7%. Mean gradient was 7.0 ± 4.6 mmHg and effective orifice area 2.0 ± 0.6 cm² . Paravalvular regurgitation was more than mild in 7.2%. A new permanent pacemaker was implanted in 15.7%. Early safety was demonstrated in 91.2%. At 30 days, all-cause mortality was 3.2%, stroke 3.7%, and major vascular complication 2.3%.

CONCLUSIONS

Real-world experience of the 34 mm Evolut R transcatheter aortic valve demonstrated acceptable procedural success, safety, valve function, and incidence of new permanent pacemaker implantation.

A randomized trial comparing two stent sizing strategies in coronary bifurcation treatment with bioresorbable vascular scaffolds - The Absorb Bifurcation Coronary (ABC) trial

BACKGROUND

Limited information is available on the use of Bioresorbable Vascular Scaffold (BVS) in bifurcations involving significant side branches. When treating bifurcation disease with metal stents, the recommendation is to choose a stent diameter based on the distal main vessel diameter. Whether this sizing strategy is applicable to BVS is currently unknown.

METHODS

We randomised 37 patients undergoing elective PCI for 'false' bifurcation disease (Medina 0,1,0; 1,0,0; 1,1,0) to receive BVS based either on proximal or distal reference diameters. Optical Frequency Domain Imaging (OFDI) measurements were performed pre BVS insertion to obtain proximal and distal reference diameters and post implantation. BVS size was chosen according to the proximal or distal reference diameter as per randomisation. Implantation was performed using the PSP technique tailored to bifurcation stenting. OFDI was repeated post implantation to confirm satisfactory expansion and apposition.

RESULTS

Baseline demographics between the two groups were similar. Patients were aged 62.8 ± 3.3 years; 76% were male. Mean side branch diameter was 2.24 ± 0.13 mm. TIMI III flow in the main vessel was achieved in all cases. Side branch occlusion occurred in 1 case (2.7%). In the distal-sizing arm, there was a greater incidence of significant malapposition (>300 μm) at the proximal end of the scaffold on OCT (2.3% versus 0.8%, p 0.023). The incidence of distal edge dissections was numerically greater in the proximal-sizing group but this was not statistically significant (31.3% vs 11.8%, p 0.17).

CONCLUSION

Both proximal and distal sizing strategies have similar procedural complication rates when using the ABSORB BVS to treat coronary bifurcations. However a proximal sizing strategy is associated with less malapposition and may be preferable.

Initial Experience of a Second-Generation Self-Expanding Transcatheter Aortic Valve: The UK & Ireland Evolut R Implanters' Registry

OBJECTIVES

The authors present the UK and Irish real-world learning curve experience of the Evolut R transcatheter heart valve.

BACKGROUND

The Evolut R is a self-expanding, repositionable, and fully recapturable second-generation transcatheter heart valve with several novel design features to improve outcomes and reduce complications.

METHODS

Clinical, procedural, and 30-day outcome data were prospectively collected for the first 264 patients to receive the Evolut R valve in the United Kingdom and Ireland.

RESULTS

A total of 264 consecutive Evolut R implantations were performed across 9 centers. The mean age was 81.1 ± 7.8 years, and the mean logistic European System for Cardiac Operative Risk Evaluation score was 19.9 ± 13.7%. Procedural indications included aortic stenosis (72.0%), mixed aortic valve disease (17.4%), and failing aortic valve bioprostheses (10.6%). Conscious sedation was used in 39.8% of patients and transfemoral access in 93.6%. The procedural success rate was 91.3%, and paravalvular leak immediately after implantation was mild or less in 92.3%. Major complications were rare: cardiac tamponade in 0.4%, conversion to sternotomy in 0.8%, annular rupture in 0.0%, coronary occlusion in 0.8%, major vascular in 5.3%, acute kidney injury in 6.1%, new permanent pacemaker implantation in 14.7%, and procedure-related death in 0.0%. At 30-day follow-up, survival was 97.7%, paravalvular leak was mild or less in 92.3%, and the stroke rate was 3.8%.

CONCLUSIONS

This registry represents the largest published real-world experience of the Evolut R valve. The procedural success rate was high and safety was excellent, comparable with previous studies of the Evolut R valve and other second-generation devices. The low rate of complications represents an improvement on first-generation devices.

Left Main Stem Percutaneous Coronary Intervention - Data and Ongoing Trials

Left main stem (LMS) disease is associated with significant morbidity and mortality. Traditionally coronary artery bypass grafting (CABG) has been the gold standard for treatment of these lesions. However over the past decade, percutaneous coronary intervention (PCI) has assumed a more prominent role in the treatment of LMS disease. With the advent of newer drug-eluting stents (DES) with an improved risk factor profile, better intravascular imaging modalities and careful patient selection, the use of PCI in this cohort is expanding. We review the current data to support this and discuss the on-going trials that will hopefully shed more light into the management of this complex disease.

Transradial Secondary Arterial Access for Transcatheter Aortic Valve Implantation: Experience and Limitations

OBJECTIVES

The transradial approach limits vascular complications in coronary interventions. The same may be true for transcatheter aortic valve implantation (TAVI). We present our experience using secondary transradial arterial access.

METHODS

Secondary transradial arterial access has been our default strategy for TAVI since 2007. Procedural data is collected prospectively. We assessed procedural success and complications.

RESULTS

Data from 282 patients aged 81±5.2 yrs was examined. Secondary arterial access was transradial (74%), femoral (24%) and none (2%). Secondary femoral access was reserved for failed radial access (3%), anatomical anomalies (4%), operator preference (7%), trial requirements (6%) or proctor preference (4%). The principal pathology was aortic stenosis (90.8%), aortic regurgitation (6.7%) or a combination (2.5%). CoreValve (91.4%), Edwards (7%) or Lotus valves (1.7%) were delivered via transfemoral (88.6%), direct aortic (5.3%), subclavian (3.9%) or transapical approaches (1.8%). Significant vascular complications occurred in 25 cases (9.4%), including surgical repair of a failed percutaneous closure device (n=16), ilio-femoral dissection (n=3), iliac perforations (n=3), plaque disruption (n=1) and false aneurysm (n=2), one of which was from the secondary femoral access site. There was no local vascular complication from the secondary radial site.

CONCLUSIONS

The transradial secondary access route for TAVI is safe and effective. The transradial route may limit vascular access complications from secondary transfemoral access.

An unusual cause of ST elevation myocardial infarction (STEMI)

A 67-year-old Caucasian woman presented to clinic with a 2-month history of worsening shortness of breath on exertion and a single episode of chest pain 1 week before. Her ECG in clinic showed ST elevation inferiorly and she was admitted from clinic for further investigations as inpatient. She was initiated on the acute coronary syndrome protocol and underwent emergency left heart catheterisation on the day of admission. The coronary angiogram revealed large aneurysmal dilations in the right coronary artery and left main stem. A ventriculogram showed poor left ventricular (LV) systolic function in line with subsequent transthoracic echocardiogram, which revealed her to have an left ventricular ejection-fraction (LVEF) of approximately 20%. It was agreed with the cardiothoracic surgeons to treat the aneurysms non-operatively and start low-molecular weight heparin. Furthermore the underlying biventricular impairment was treated with ACE-inhibitors, β-blockers and diuretic therapy (loop and potassium-sparing). The strategy was to prevent further thrombus formation with the aneurysmal vessels and to achieve this the patient was initiated on lifelong warfarin. Other medical risk factors were optimised and patient started on statin medication. The aneurysm was monitored with serial CTs with a view to reconsider surgical intervention if any evidence of dilation. This case highlights an unusual cause of ST elevation myocardial infarction.