One-year results from the FLXibility post-approval study: final real-world clinical outcomes with a next-generation left atrial appendage closure device

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Boston Scientific Corporation, Marlborough, MA, USA

Background

The WATCHMAN FLX left atrial appendage (LAA) closure device received CE-mark and FDA approval based on the results of the PINNACLE FLX IDE study, but evidence of outcomes with this next-generation device in everyday clinical practise is limited.

Purpose

The FLXibility Post-Approval Study collected real-world data on patients implanted with a WATCHMAN FLX in a routine clinical practise.

Methods

Patients were implanted with a WATCHMAN FLX per local standard of care, with a subsequent first follow-up visit from 45-120 days post-implant and a final follow-up at 1 year post procedure. A Clinical Event Committee adjudicated all major adverse events and TEE/CT imaging results were adjudicated by a core laboratory.

Results

Among 300 patients enrolled at 17 centres in Europe, the mean age was 74.6±8.0 years, mean CHA2DS2-VASc score was 4.3±1.6, mean HAS-BLED score was 2.6±1.0, and 62.1% were male. The device was successfully implanted in 99.0% (297/300) of patients; 97.0% (289/298) required only 1 device for an implantation attempt and no patient required >2 devices. TEE was used for 78% of procedures and ICE for 22%. The post-implant medication regimen was DAPT for 87.3% (262/300). At first follow-up, among 170 patients with evaluable imaging, 87.6% (149/170) had no leak, 12.4% (21/170) had leak >0mm to ≤5mm with 16 (9.4%) of these <3mm, and no patient had leak >5mm, per core lab adjudication. At 1 year, 93.3% (280/300) patients had final follow-up or death. At final follow-up, 61% of patients were on a single antiplatelet medication, 21% were on DAPT, 6% were on a direct oral anticoagulation medication, and 12% were not taking any antiplatelet/anticoagulation medication. One-year all-cause mortality was 10.8% (32/295), among which 5.1% (15/295) were cardiovascular or unexplained. Disabling stroke occurred in 1.0% (3/295) of patients and nondisabling stroke also in 1.0% (3/295) of patients; all were nonfatal. No patient experienced a systemic embolism. Device-related thrombus was detected in 2.4% (7/295) patients. Pericardial effusion requiring surgery or pericardiocentesis occurred in 1.0% (3/295), with all of these events occurring in the first 7 days post-procedure. Cumulative BARC-3 or -5 bleeding occurred in 3.7% (11/300) of patients from 0 to 7 days, in 7.3% (22/300) at 6 months, and in 8.1% (24/295) patients at 1 year. One patient (0.3%) had a peri-procedural device embolisation, with no subsequent device embolisations or any device migration reported for any patient through 1 year.

Conclusions

The WATCHMAN FLX device had excellent procedural success rates, with high effective LAA closure rates and low serious adverse event rates in everyday clinical practise.

Transcatheter aortic valve implantation with the LOTUS Edge system: early European experience

Aims

To evaluate the clinical outcomes of transcatheter aortic valve implantation (TAVI) with the recently commercialised LOTUS EdgeTM system.

Methods and results

We performed a multicentre, single-arm, retrospective registry to generate early information on patients undergoing TAVI with the LOTUS EdgeTM system following its commercial release in July 2019. Novel features of this second-generation device include increased flexibility of the delivery catheter, enhanced visualisation of the locking mechanism and the depth guard technology to reduce left ventricular outflow tract interaction and, potentially, reduce the risk of permanent pacemaker (PPM) implantation. All endpoints were defined according to the VARC-2 definitions and were reported by the treating site.

A total of 286 consecutive patients from 18 participating centres were included. The mean age and STS score were 81.2±6.9 years and 5.2±5.4%, respectively. Most procedures were performed under local anaesthesia (97.2%) via transfemoral access (98.6%).

Successful vascular access, valve delivery and deployment and system retrieval were achieved in 97.6% of cases. 30-day rates of all-cause mortality (2.1%, N=6) and stroke (3.5%, N=10) were acceptable. Disabling, life-threatening or major bleeding occurred in 3.8% and major vascular complications in 2.1%. The incidence of new PPM implantation was 27.1% among all patients and 32.2% among pacemaker-naive patients. After TAVI, the mean transvalvular pressure gradient was 11.9±5.6 mmHg and the mean aortic valve area was 1.9±0.9 cm2. The rate of moderate paravalvular leak was 2.1% with no cases of severe paravalvular leak.

Conclusions

Early experience with the LOTUS EdgeTM system demonstrated acceptable 30-day clinical outcomes with impressively low rates of paravalvular leak. The requirement for new PPM remained high in this early experience. Further study is required to understand if improving operator experience with the device can reduce PPM rates.

Funding Acknowledgement

Type of funding source: None

New onset left bundle branch block after transcatheter aortic valve implantation and the effect on long-term survival – a UK wide experience

Introduction

New onset left bundle branch block (LBBB) is the most common conduction disturbance associated with transcatheter aortic valve implantation (TAVI). It has been shown to adversely affect cardiac function and increase re-hospitalisation, although its impact on mortality remains contentious.

Methods

We conducted an observational cohort analysis of all TAVI procedures performed by 13 heart teams in the United Kingdom from inception of their structural programmes until 31st July 2013. The primary outcome was 1-year all-cause mortality. Secondary outcomes included left ventricular ejection fraction (LVEF) at 30 days and need for a post-TAVI permanent pacemaker (PPM).

Results

1785 patients were eligible for inclusion to the study. The primary analysis cohort was composed of 1409 patients with complete electrocardiographic (ECG) data pre- and post-TAVI. Pre-existing LBBB was present in 200 (14.2%) patients. New LBBB occurred in 323 (22.9%) patients post TAVI, which resolved in 99 (7%) patients prior to discharge. A balloon-expandable device was implanted in 968 (69%) patients, whilst 421 (30%) patients received a self-expandable valve. New LBBB was observed in 120 (12.4%) and 192 (45.6%) patients receiving a balloon- or self-expandable prosthesis respectively.

Overall 1-year all-cause mortality post TAVI was 18.7%. New onset LBBB was not associated with an increase in 1-year all-cause mortality (p=0.416). Factors that were associated with mortality included an increasing logistic EuroScore (p=0.05), history of previous balloon aortic valvuloplasty (p=0.001), renal impairment (p=0.003), previous myocardial infarction with pre-existing LBBB (p=0.028) and atrial fibrillation (p=0.039). Lower baseline peak and mean AV gradients were also associated with greater mortality at 1 year (p=0.001), likely reflecting underlying left ventricular dysfunction.

In the majority of patients, LVEF remained unchanged following TAVI. Interestingly, the presence or absence of new onset LBBB did not affect LVEF improvement at 30 days. 10% of patients required a PPM post TAVI. Predictors of PPM included new LBBB (OR 2.6, p<0.001), pre-TAVI left ventricular systolic impairment (OR 1.2, p=0.037), a self-expandable device (p<0.001), and pre-existing RBBB (OR 4.0, p<0.001).

Conclusions

These findings suggest that new onset LBBB post TAVI does not increase mortality at 1 year or adversely affect LVEF at 30 days.

Funding Acknowledgement

Type of funding source: None

94Course of contained annulus ruptures after TAVI: the ENCORE (European contained rupture)-registry

Background

An asymptomatic contained rupture (CR) of the aortic annulus is a rare complication of transcatheter aortic valve implantation (TAVI). Their clinical implication is unclear so far.

Purpose

To determine the long-term outcomes in patients with CR.

Methods

The ENCORE-registry is a multicenter registry (6 centers across Europe) of patients with CR diagnosed on post-TAVI computed tomography angiography (CTA) or transesophageal echocardiography (TEE).

Results

A total of 21 patients (mean age 81.9±4.1 years, 81% balloon-expandable TAVI-prostheses) were diagnosed with CR (62% located adjacent to the left coronary cusp, mean size of lesions was 15.3±6.9 x 8.5±3.3 x 8.5±2.3 mm). Seventeen were diagnosed among a total of 1602 consecutive routine post-TAVI CTA (incidence 1.1%), two in TEE and two in post-TAVI CTA (each conducted due to suspicion of periinterventional complications). During a mean follow-up of 2.3±1.7 years nine patients (43%) died from non-cardiac causes. None of the patients exhibited symptoms or underwent interventional treatment related to the CR, no sudden cardiac death occurred. A follow-up CTA, performed in eleven patients 240±176 days post-TAVI, revealed stable CR findings in seven, regression in one, and remission in three patients.

Conclusion

The results of our ENCORE-registry demonstrate a benign course of initially asymptomatic contained ruptures of the aortic annulus after TAVI supporting a watch-and-wait approach in these patients. Thus, no specific treatment seems to be necessary.

3326Infective endocarditis after transcatheter aortic valve implantation: findings from a UK nationwide linkage study

Introduction

Infective endocarditis (IE) is a potentially fatal complication of prosthetic valve replacement and increasing use of transcatheter aortic valve implantation (TAVI) has resulted in a new elderly and frail population at increased risk of IE. The incidence of IE after TAVI and factors that influence the risk and subsequent outcome are relatively unknown.

Purpose

To describe the incidence, predictors, echocardiographic findings, microbiology and clinical outcomes of IE following TAVI in the United Kingdom (UK).

Methods

Patients who underwent TAVI between Jan 1 2007 and Dec 31 2016 were identified from the UK TAVI database held by the National Institute for Cardiovascular Outcomes Research. For this cohort, all hospital admissions with a primary diagnosis of IE were identified by linkage with the NHS Hospital Episode Statistics Admitted Patient Care database, or by contact with regional TAVI centres. Additional information concerning clinical presentation, imaging findings, microbiology, management and patient outcome were obtained where possible from the treating physician.

Results

A total of 16,014 patients underwent TAVI, of whom 157 developed IE over a median follow-up of 23.8 (IQR 7.8–52.4) months - an overall incidence of 0.98% (0.53% at one year post-TAVI). The mean age of patients with IE was 79.2±7.8 years, and 69% were male. The median time to IE following TAVI was 10.0 (IQR 4.0–22.3) months.

On multivariate analysis, IE was significantly more common in men (HR 2.05, 95% CI 1.35–3.11, p=0.001) and in patients receiving mechanically-expandable (HR 2.15, 95% CI 1.16–4.01, p=0.015) or balloon-expandable valves (HR 1.60, 95% CI 1.01–2.52, p=0.045) compared to self-expanding valves. IE was also more common in those with an aortic valve peak gradient following TAVI deployment greater than median (HR 1.81, 95% CI 1.23–2.67, p=0.003).

The most common presenting symptom was fever (present in 67.1%). The most frequent causal organisms were enterococci (25.9%), followed by oral streptococci (16.4%) and Staphylococcus aureus (11.8%). Transoesophageal echocardiography demonstrated vegetations in 72.5% of patients, most commonly on the TAVI valve leaflets (58.8%). Only 8.24% of patients underwent surgical valve intervention.

Survival rates at hospital discharge and one year follow up were 61.4% and 54.4%, respectively. Specific factors associated with one-year mortality were cardiogenic shock (HR 4.6, 95% CI 2.1–10.3, p=0.0002), septic shock (HR 3.4, 95% CI 1.4–8.3, p=0.006) and stroke (HR 4.9, 95% CI 1.46–16.7, p=0.01).

Conclusions

The incidence of IE one year after TAVI was 0.53% and greater risk was associated with male sex, mechanically-expandable and balloon-expandable valves, and elevated post-deployment valve gradient. Enterococci were the most common causative organism. Overall survival at one year was 54.4%, with adverse outcome predicted by cardiogenic shock, septic shock or stroke.

P2807Clinical outcomes with cobalt chromium biolimus eluting drug-eluting stents compared with stainless steel biolimus eluting drug-eluting stents in all-comers patients

Aims

Thinner stent struts may improve deliverability, conformability and reduce vessel injury. We report the first clinical outcomes of the thinner strut (84–88um) cobalt chromium biolimus eluting stent from the Biomatrix Alpha registry and compare these with objective performance criteria from the stainless steel BioMatrix Flex arm of the Leaders study.

Methods

A total of 1257 patients were studied: 400 patients from 12 centres receiving ≥1 Biomatrix Alpha stent were prospectively enrolled into the Biomatrix Alpha registry and then underwent a pre-specified comparison with 857 patients who received a Biomatrix Flex stent in the Leaders study. The primary endpoint was major adverse cardiac events (MACE) defined as the composite of cardiac death, myocardial infarction (MI) or clinically driven target vessel revascularization (TVR) at 9 months. Assuming a 9.2% event rate with BioMatrix Flex, a one-sided type I error (α) of 0.05, and a 4% non-inferiority margin, a sample size of 400 in the Biomatrix alpha registry had >80% power to conclude non-inferiority.

Results

Baseline characteristics in the Alpha registry were typical of an all-comers population with a mean age of 64.7±11.3, diabetes 19%, current smoking 21%, dyslipidemia 57%, hypertension 57%, total stent length per lesion 25.49±13.45, mean stents per procedure 1.59±0.88 and overlapping stents in 13.4%. Observed MACE at 9 months with Alpha was 3.94% (upper limit 5.98%) vs. 9.28% MACE rate with Flex stents in Leaders, which met pre-specified criteria for non-inferiority (p<0.001) and on post hoc testing for superiority yielded p<0.001 for Alpha vs Flex. Secondary endpoints with Alpha included clinically-driven TVR 2.6%, all-cause mortality rate 1.51% and definite/probable stent thrombosis 0.25%.

While both Alpha and Leaders enrolled all-comers, Alpha included longer total stent length per lesion (25.49 vs 23.85mm, p<0.001) and more stents per procedure (mean 1.59 vs 1.34; p<0.001) but fewer patients with diabetes (19% vs 26%; p=0.0087), dyslipidemia (57 vs 65%; p=0.0037), prior MI (18.8% vs 32.2%; p<0.001) or acute coronary syndrome (41% vs 55%; p<0.001). To correct for these imbalances and to assess robustness further, a propensity score at the patient level data was undertaken (total sample size of 1257 patients; 400 from the Alpha registry and 857 from the LEADERS study). A propensity score stratification method was used obtaining 5 quintiles for adjusted analysis (each of the 5, containing 251 or 252 patients, 20%). In each of the strata as well as at the aggregate level, a p valve<0.005 was obtained confirming non-inferiority for the primary endpoint.

Conclusion

The thinner strut (84–88um) cobalt chromium Biomatrix Alpha stent demonstrated low MACE rates at 9 months which were non-inferior to MACE outcomes with the stainless steel Biomatrix Flex in the Leaders study. The robustness of this finding was further confirmed by a propensity score analysis.

Acknowledgement/Funding

Biosensors

Percutaneous paravalvular leak closure for symptomatic aortic regurgitation after CoreValve transcatheter aortic valve implantation

OBJECTIVES

We present a case series of five patients in whom percutaneous paravalvular leak closure with the AVP4 device has been undertaken for symptomatic aortic regurgitation after CoreValve TAVI.

BACKGROUND

Significant post-procedure aortic regurgitation (AR) is often difficult to assess, and is an important predictor of adverse outcome following TAVI. Paravalvular leak closure is an established procedure for surgical aortic prostheses, and has been undertaken for Edwards TAVIs, but has not been described for closure of CoreValve paravalvular leaks.

METHODS AND RESULTS

Five patients were treated (mean age 81 ± 4 years) with residual grade 3-4 AR following placement of a single CoreValve (n = 2), double CoreValve (n = 2) or CoreValve within a bioprosthetic AVR (n = 1). The mean time post TAVI implantation was 308 ± 269 days. All patients were symptomatic with persistent NYHA Grade III dyspnoea. 6 devices were deployed successfully, with mean procedure time of 109 ± 23 min. There were no procedural complications and all patients were discharged home by Day 2. Residual AR after treatment was grade 0 (n = 2), grade 1 (n = 1), grade 2 (n = 1) and grade 3 (n = 1). Symptomatic improvement was noted in all 4 patients who have been reviewed in clinic since.

CONCLUSIONS

This small series demonstrates the feasibility of paravalvular leak closure with the CoreValve TAVI, despite the adverse aortic lattice. The AVP4 device is ideally suited to this situation as it will pass through a 0.038' lumen and can therefore be delivered down standard diagnostic catheters.

Changing the coronary bifurcation angles after stenting procedures: the relevance to the technique and unfavorable outcome (Three-dimensional analysis)

AIM

Percutaneous transluminal balloon co-ronary angioplasty (PTCA) of coronary bifurcations is associated with a low success rate, higher rate of complications and need for revascularazation. We sought to analyze: 1) the change in 3D measurement of angles following stenting of coronary bifurcations; and 2) if changes in these angles might predict unfavourable outcomes.

METHODS

Coronary angiograms of 102 patients with bifurcation lesions were analyzed with 3D software (CardiOp-B) before and after stenting. The change in angle between the proximal main artery and side branch (BA), and between the distal main artery and side branch (BS) were measured. A change of ≥ 5° after stenting was considered significant. The results were compared with clinical follow-up.

RESULTS

Bifurcation lesions included 66 left anterior descending/first diagonal (LAD/D1) lesions, 15 left main stem (LMS) lesions, 19 atrioventricular circumflex/obtuse marginal (AVCx/OM) lesions, and 2 coronary artery (RCA) crux lesions. BA and BS measured 138.3° ± 17.2° and 64.3° ± 20.6° respectively. Stent deployment altered BA and BS significantly in 80-90% of cases. Furthermore, BS correlated positively with the magnitude of change in BS after stenting. BA was unaffected by the complexity of the stenting procedure, whereas BS increased significantly in complex versus simple stenting strategies (P<0.05). Procedure related complications occurred in 15.6% of patients. The incidence of in-hospital complications was lower when BA was increased (P<0.05). The one year incidence of the composite of in-hospital complications and late complications was also significantly lower when BA was increased by ≥ 5° (P=0.027). A decrease of BA was associated with 80% more complications compared to cases where BA was increased. No correlation was found between the change of BS and procedural or late complications.

CONCLUSION

3D measurements of coronary bifurcation angles prior to stenting can predict changes in bifurcation geometry after stenting. A decrease in BA after stenting is a strong predictor for less favourable outcomes of coronary bifurcation stenting procedures.

Permanent pacemaker insertion after CoreValve transcatheter aortic valve implantation: incidence and contributing factors (the UK CoreValve Collaborative)

BACKGROUND

Permanent pacemaker (PPM) requirement is a recognized complication of transcatheter aortic valve implantation. We assessed the UK incidence of permanent pacing within 30 days of CoreValve implantation and formulated an anatomic and electrophysiological model.

METHODS AND RESULTS

Data from 270 patients at 10 centers in the United Kingdom were examined. Twenty-five patients (8%) had preexisting PPMs; 2 patients had incomplete data. The remaining 243 were 81.3±6.7 years of age; 50.6% were male. QRS duration increased from 105±23 to 135±29 milliseconds (P<0.01). Left bundle-branch block incidence was 13% at baseline and 61% after the procedure (P<0.001). Eighty-one patients (33.3%) required a PPM within 30 days. Rates of pacing according to preexisting ECG abnormalities were as follows: right bundle-branch block, 65.2%; left bundle-branch block, 43.75%; normal QRS, 27.6%. Among patients who required PPM implantation, the median time to insertion was 4.0 days (interquartile range, 2.0 to 7.75 days). Multivariable analysis revealed that periprocedural atrioventricular block (odds ratio, 6.29; 95% confidence interval, 3.55 to 11.15), balloon predilatation (odds ratio, 2.68; 95% confidence interval, 2.00 to 3.47), use of the larger (29 mm) CoreValve prosthesis (odds ratio, 2.50; 95% confidence interval, 1.22 to 5.11), interventricular septum diameter (odds ratio, 1.18; 95% confidence interval, 1.10 to 3.06), and prolonged QRS duration (odds ratio, 3.45; 95% confidence interval, 1.61 to 7.40) were independently associated with the need for PPM.

CONCLUSION

One third of patients undergoing a CoreValve transcatheter aortic valve implantation procedure require a PPM within 30 days. Periprocedural atrioventricular block, balloon predilatation, use of the larger CoreValve prosthesis, increased interventricular septum diameter and prolonged QRS duration were associated with the need for PPM.

Transradial coronary intervention without pre-screening for a dual palmar blood supply

It is usual practice to determine the presence of collateral blood supply to the hand prior to radial artery cannulation. We propose that pre-screening for a dual palmar vascular supply is not necessary and the presence of a palpable radial pulse is sufficient to allow successful radial artery cannulation. We retrospectively analysed our interventional PTCA registry, including only patients who had a transradial procedure without being pre-screened with an Allen's test or plethysmography. We report our data including complications the day after the procedure and at 30 days, and provide an up to date discussion on the need to assess patients for a dual palmar blood supply prior to transradial intervention.

Percutaneous closure of an aortic paravalvular leak via the transradial approach

Percutaneous closure of aortic and mitral paraprosthetic leaks using the Amplatzer occluders (muscular ventricular septal defect occluder) is now a well recognized procedure although as "off label" use. Aortic paravalvular leak closure is usually carried out via transfemoral puncture, but problems with this approach include the need to stop warfarin and the inadequate length of standard delivery sheaths. We report the first case of percutaneous aortic paravalvular leak closure through the radial artery route.

Transient ST-segment changes associated with mitral valvuloplasty using the Inoue balloon

We describe unexplained transient inferior ST-segment elevation on the electrocardiogram during Inoue mitral valvuloplasty in 8 patients from a series of 108. Electrocardiographic changes were associated with chest pain in 7 patients, and although the clinical features were suggestive of myocardial ischemia, no cause for this could be found.