CT-determined tricuspid annular dilatation is associated with persistence of tricuspid regurgitation after transcatheter aortic valve replacement

Introduction

Moderate or severe tricuspid regurgitation (TR) can be observed in 11% to 27% of patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Even though in most patients an improvement of TR can be achieved after TAVR, the persistence of severe or massive TR after the procedure is associated with increased all-cause mortality.

Purpose

The aim of this study was to investigate if tricuspid annular dilatation (TAD) measured in pre-procedural CT among TAVR patients who had at least moderate TR at baseline could serve as a predictor for the persistence of TR. Moreover, the predictive value of TR persistence on the composite of 2-year mortality or tricuspid valve intervention was analysed.

Methods

We examined 151 patients with severe AS and at least moderate concomitant TR at baseline, who were treated with TAVR from April 2013 to December 2019. TR persistence was defined as the same or a higher grade of TR in the follow-up echocardiography at least 30 days after the procedure compared to preprocedural TR grade. To identify patients with TAD, the maximum septolateral diameter of the tricuspid annulus was measured in pre-procedural cardiac computed tomography images and normalized to the body surface area.

Results

The median value of 25.5 mm/m2 was determined as cut-off value for TAD. Out of 151 patients with moderate or more TR before TAVR, 75 patients (49.7%) were above the threshold of 25.5 mm/m2. Improvement of TR after TAVR of at least one grade was significantly more frequent in patients without TAD than with TAD (59% vs. 32%, corresponding odds ratio for persistence of TR: 3.06, 95% confidence interval: 1.50–6.35, p=0.001) (Figure 1A). Multivariable logistic regression analysis with adjustment for baseline TR severity confirmed that the predictive value of TAD for TR persistence after TAVR was irrespective of baseline TR (adjusted odds ratio: 2.79, 95% confidence interval: 1.42–5.59, p=0.003). Tricuspid valve intervention was conducted in 11 patients with TAD after TAVR (14.6%) and in no patients without TAD. Accordingly, at 2-years, tricuspid valve intervention-free survival was lowest among patients with TAD and persistent TR (Figure 1B).

Conclusion

Our analysis demonstrates for the first time that in patients undergoing TAVR for severe AS and at least moderate concomitant TR, CT-derived TAD is associated with persistence of TR after the procedure. Furthermore, TR persistence is associated with an adverse outcome.

Funding Acknowledgement

Type of funding sources: None.

Suture-based vs. pure plug-based vascular closure devices for VA-ECMO decannulation

Background

VA-ECMO is a valuable treatment option for patients in cardiogenic shock, but complications during decannulation may worsen the overall outcome. To date, no larger study has ever compared suture-based to pure plug-based vessel closure devices for VA-ECMO decannulation.

Purpose

The aim of the study was to compare the efficacy and safety of suture-based to pure plug-based vascular closure devices for veno-arterial extracorporeal membrane oxygenation (VA-ECMO) decannulation for patients with cardiogenic shock.

Methods

In this retrospective study, the outcome of 33 patients with suture-based closure devices implanted between 02/2019 to 05/2020 were compared to 38 patients with plug-based closured device implanted between 06/2020 to 11/2021.

Results

Closure device success rate was 88% in the suture-based group versus 97% in the plug-based group (Figure 1, p=0.27). Median number of devices used was two for patients with suture-based closure device and 1 for patients with plug-based closure device (p<0.01). Severe bleeding was more frequent in the suture-based (21%) compared to the plug-based group (3%) (Figure 2, p=0.04). Ischemic complications occurred in 6% with suture-based and 5% with plug-based device (p=1.00). Pseudoaneurysm formation was detected in 3% in both groups (p=1.00). Application of the femoral compression system was required in 27% of patient with suture-based closure device and 11% of patients with plug-based closure device (p=0.13). No switch to open vascular surgery due to closure device failure occurred in both groups.

Conclusions

Based on our retrospective analysis, we propose that plug-based vascular closure should be the preferred option for VA-ECMO decannulation. This hypothesis should be further tested in a randomized trial.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft

TAVR in patients with low-flow low-gradient aortic stenosis – outcome data after three years from one large centre

Background

The outcome of patients with low-flow low-gradient (LFLG) aortic stenosis after transcatheter aortic valve replacement (TAVR) is not well evaluated. Long-term clinical success is thought to be less pronounced in LFLG patients compared to patients with high gradient (HG) aortic stenosis.

Purpose

The purpose of this study was to characterise different LFLG groups and determine their outcome after TAVR. We hypothesised that there would be relevant differences in baseline characteristics and patient survival after TAVR.

Methods

All patients undergoing TAVR for severe aortic stenosis at our centre between 2013 and 2019 were included in the study. Patients have been split into groups according preinterventional echocardiography data according to mean pressure gradient (dPmean), ejection fraction (EF), and stroke volume index (SVi). Patients with a dPmean <40 mmHg and SVi ≤35 ml/m2 were subdivided into classical low-flow low-gradient (cLFLG, EF <50%) and paradoxical low-flow (pLFLG, EF ≥50%). Patients with previous aortic valve replacement or severe aortic regurgitation were excluded from the analysis.

Results

1,772 patients were analysed (mean follow-up 2.2 years, median age 81.7 [77.5–85.7] years) and split into groups: HG, 953 patients (54.3%), cLFLG, 446 patients (25.2%), and pLFLG 373 patients (21.1%). Baseline characteristics showed significant differences (p<0.01), among others, in sex (male sex, HG 46.1% vs. cLFLG 69.5% vs. pLFLG 44.5%), rate of atrial fibrillation (HG 20.3% vs. cLFLG 36.3% vs. pLFLG 41.6%), coronary artery disease (HG 56.2% vs. cLFLG 73.5% vs. pLFLG 63.4%), and grade 3 or 4 mitral regurgitation (HG 2.2% vs. cLFLG 5.5% vs. pLFLG 6.8%). Accordingly, Society of Thoracic Surgeons (STS) Scores differed significantly: HG, 3.0 [2.0–5.0], cLFLG, 5.0 [3.0–7.3] pLFLG, 3.9 [2.2–6.0] (p<0.01).

Rates of periprocedural complications including death, device failure, pericardial effusion, stroke or myocardial infarction were comparable between groups. Mortality rate (figure 1) was highest for cLFLG patients (43.4% [95% confidence interval, 37.3–48.6%]) compared to HG (25.1% [21.6–28.5%]) or pLFLG (32.9% [26.9–38.4%]), Log-rank test, <0.001. Corresponding hazard ratios were 2.1 [1.7–2.6] (p<0.001) for cLFLG and 1.5 [1.2–2.0] (p<0.001) for pLFLG. Similar results were obtained when adjusting to STS score (figure 2).

Conclusion

In this all-comer analysis, almost half of the patients belong toLFLG groups with considerable differences in patient characteristics. While equally safe during the procedure, patients with LFLG aortic stenosis show increased 3-year mortality rates compared to patients with HG aortic stenosis. Further studies evaluating this are needed.

Funding Acknowledgement

Type of funding sources: None. Figure 1. 3-year mortalityFigure 2. STS score-adjusted mortality

Quantification of physical activity with activity tracking after transfemoral aortic valve replacement (TAVR)

Background and hypothesis

TAVR is a well-established, safe and effective therapy for severe symptomatic aortic stenosis (AS), but improvement of physical activity after TAVR is difficult to assess objectively. The aim of this study was to quantify improvement of physical activity with Activity Tracking after TAVR with special focus on the different low-gradient subtypes of AS.

Methods

All patients who underwent TAVR for severe AS in our center between 01/2019 and 12/2019 were screened. Participants received an Activity Tracker for 7 days at two times: after hospital discharge following TAVR procedure and 6 months thereafter. The difference of mean daily steps was defined as study endpoint.

Results

The analysis is based on 230 patients. The median age was 79.7 years with 53.7% male participants. The median aortic valve area (AVA) was 0.75 cm2 and median mean pressure gradient was 38.7 mmHg (Table 1). The median amount of daily steps was 4409 [IQR 2581–7487] steps/day after hospital discharge and 5326 [IQR 3045–8668] steps/day 6 months thereafter. On a patient base, median difference of steps per day was Δ 529 [IQR −702–2152]). Whenever possible, patients were categorized into different subgroups of AS. Patients with high-gradient (HG) AS showed significant improvement in difference of daily steps at 6 months-FUP (Δ 951 [IQR −378–2.323], p<0.001), as well as patients with paradox low-flow-low-gradient (LFLG) AS (Δ 1392 [IQR −609–4444], p=0.02). Patients with classical LFLG AS also showed an improvement of daily steps at 6-months-FUP but without statistical significance (Δ 192 [IQR −687–770], p=0.79). Patients with a normal-flow-low-gradient (NFLG) AS have no significant difference in daily steps after 6-months and show a tendency of decline in daily steps at 6-months-FUP (Δ −300 [IQR −1334–1406], p=0.67) (Figure 1).

Conclusions

This is the first study of this sample size to evaluate physical activity after TAVR with an objective and reproducible method. Overall, physical activity improved significantly 6 months after TAVR and daily steps per day increased in all subtypes of AS besides NFLG AS, where a tendency of decline in daily steps without statistical significance was shown. However the increase in daily steps did not reach statistical significance in classical LFLG AS patients.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

Incremental prognostic value of tricuspid annular dilatation over the STS score

Background

Transcatheter aortic valve replacement (TAVR) is the treatment of choice in most patients with severe aortic stenosis. The Society of Thoracic Surgeons (STS) score is a well established risk score to estimate morbidity, mortality and procedural risk of patients undergoing TAVR. However, tricuspid annular Dilatation (TAD), which is an increasingly recognized pathology associated with increased mortality, is not implemented in the STS Score.

Purpose

The purpose of this analysis was to investigate the incremental prognoctic value of TAD over the STS score.

Methods

Maximal septo-lateral diameter of the tricuspid annulus was measured in 923 patients on 3-dimensional MDCT datasets. A cut-off of 23 mm/m2 body-surface area was revealed by receiver-operating curve statistics and used to define TAD. Incremental prognostic Information was tested with c-index statistics and continuous net reclassification improvement (NRI). Patients were followed for 2 years and all-cause mortality was defined as study endpoint.

Results

Of 923 patients included in this analyis, TAD was found in 370 patients (40%). Patients with TAD had a significantly higher mortality (hazard ratio 2.18 with 95% CI 1.71 and 2.78, p<0.001). The mean STS score in the investigated patient cohort was 5.6±5.0. TAD provided incremental prognostic Information over the STS score when assessed with c-index statistics (rise from 0.63 to 0.66, p<0.01) or continuous NRI (0.209 with 95% CI 0.127 and 0.292, p<0.001). Estimated survival rates at 2 years were 88.2% (95% CI 84.5 and 92.1) in patients with a low STS score (<4) and no TAD and 57.5% (95% CI 51.1 and 64.7) in patients with a high STS score (>4) and TAD. Estimated survival rates in patients with a low STS score and TAD and patients with a high STS score and no TAD were similiar (75.8% with 95% CI 68.9 and 83.5 and 74.8% with 95% CI 69.2 and 80.7, respectively). Kaplan-Meier curves are shown in Figure 1.

Conclusion

TAD is a common entity in patients undergoing TAVR for severe aortic stenosis. It is associated with significantly higher mortality and provides incremental prognostic Information over the STS score.

Funding Acknowledgement

Type of funding source: None

P5584Causes of death within the first year after transcatheter aortic valve implantation: Lessons from EVERY-TAVI registry

Background

According to current recommendations, transcatheter aortic valve implantation (TAVI) should only be performed among patients with a life expectancy of at least one year. However, many deaths occur within the first year after TAVI.

Purpose

To assess the causes of death within one year after TAVI.

Methods

Data was taken between November 2007 and December 2017 from the EVERY-TAVI registry. Patients who died during TAVI or experienced mechanical complications requiring surgery were excluded from the analysis. We assessed the causes of death over 3 periods post-TAVI: within the first 30 days, between 30 and 90 days, and between 90 and 365 days.

Results

Overall, 2389 patients underwent TAVI without mechanical complications. Among them, 320 (1.3%) died within one year. Age was the main cause of death, accounting for 73 deaths (22.8%), followed by heart failure (20.6%) and infections (18.7%). During the first month, cardiogenic shock was the main cause of death (25.4%), followed by infections (22.2%) and terminal heart failure (20.6%), while age was responsible of only one death (1.6%). During the two following months, heart failure was the main cause of death (33.3%), followed by infections (21.2%), and the percentage of deaths due to age increased to 18.2%. After 3 months, age was the main cause of death (31.4%), followed by infection (16.8%) and heart failure (16.2%).

Causes of death within one year of TAVI Cause of death All (n=320) <30 days (n=63) 30–90 days (n=66) >90 days (n=191) Older age, n (%) 73 (22.8) 1 (1.6) 12 (18.2) 60 (31.4) Terminal heart failure, n (%) 66 (20.6) 13 (20.6) 22 (33.3) 31 (16.2) Infection, n (%) 60 (18.7) 14 (22.2) 14 (21.2) 32 (16.8) Terminal renal failure, n (%) 26 (8.1) 4 (6.3) 5 (7.6) 17 (8.9) Cardiogenic shock, n (%) 26 (8.1) 16 (25.4) 4 (6.1) 6 (3.1) Malignancies, n (%) 18 (5.6) 0 (0.0) 2 (3.0) 16 (8.4) Sudden death, n (%) 17 (5.3) 6 (9.5) 2 (3.0) 9 (4.7) Stroke, n (%) 12 (3.7) 4 (6.3) 2 (3.0) 6 (3.1) Accident, n (%) 7 (2.2) 2 (3.2) 0 (0.0) 5 (2.6) Myocardial infarction, n (%) 7 (2.2) 2 (3.2) 2 (3.0) 3 (1.6) Non-cardiac surgery, n (%) 5 (1.6) 1 (1.6) 1 (1.5) 3 (1.6) Pulmonary embolism, n (%) 3 (0.9) 0 (0.0) 0 (0.0) 3 (1.6)

Conclusion

Cardiogenic shock is the main cause within the first month after TAVI, while older age is the main cause overall and after the initial months, highlighting the need to more carefully selection of patients undergoing TAVI.

Connexin 40 promoter-based enrichment of embryonic stem cell-derived cardiovascular progenitor cells

BACKGROUND

Pluripotent embryonic stem (ES) cells that can differentiate into functional cardiomyocytes as well as vascular cells in cell culture may open the door to cardiovascular cell transplantation. However, the percentage of ES cells in embryoid bodies (EBs) which spontaneously undergo cardiovascular differentiation is low (<10%), making strategies for their specific labeling and purification indispensable.

METHODS

The human connexin 40 (Cx40) promoter was isolated and cloned in the vector pEGFP. The specificity of the construct was initially assessed in Xenopus embryos injected with Cx40-EGFP plasmid DNA. Stable Cx40-EGFP ES cell clones were differentiated and fluorescent cells were enriched manually as well as via fluorescence-activated cell sorting. Characterization of these cells was performed with respect to spontaneous beating as well as via RT-PCRs and immunofluorescent stainings.

RESULTS

Cx40-EGFP reporter plasmid injection led to EGFP fluorescence specifically in the abdominal aorta of frog tadpoles. After crude manual enrichment of highly Cx40-EGFP-positive EBs, the appearance of cardiac and vascular structures was increased approximately 3-fold. Immunofluorescent stainings showed EGFP expression exclusively in vascular-like structures simultaneously expressing von Willebrand factor and in formerly beating areas expressing alpha-actinin. Cx40-EGFP-expressing EBs revealed significantly higher numbers of beating cardiomyocytes and vascular-like structures. Semiquantitative RT-PCRs confirmed an enhanced cardiovascular differentiation as shown for the cardiac markers Nkx2.5 and MLC2v, as well as the endothelial marker vascular endothelial cadherin.

CONCLUSIONS

Our work shows the feasibility of specific labeling and purification of cardiovascular progenitor cells from differentiating EBs based on the Cx40 promoter. We provide proof of principle that the deleted CD4 (DeltaCD4) surface marker-based method for magnetic cell sorting developed by our group will be ideally suitable for transference to this promoter.