Impact of valvular resistance on aortic regurgitation after transcatheter aortic valve replacement according to the type of prosthesis

BACKGROUND

The impact of aortic valvular resistance (VR) on the degree of post-transcatheter aortic valve replacement (TAVR) aortic regurgitation (AR) remains unclear. The objective of the study was to investigate the relationship between VR and paravalvular AR after TAVR.

METHODS

Between August 2007 and December 2015, 708 TAVR patients had sufficient data to calculate VR before the intervention and were eligible for the present analysis. The patient population was dichotomized according to VR. The association between VR and post-TAVR AR was separately assessed by prosthesis type.

RESULTS

Among patients with low VR (LVR; < 238 dynes/cm⁵), 176 (49.7%) patients were treated with balloon-expandable (BE) valves and 178 (51.3%) patients with self-expandable (SE) transcatheter valves. Among patients with high VR (HVR ≥ 238), 147 (41.5%) and 207 (68.5%) patients received BE and SE, respectively. Baseline characteristics were similar in both groups irrespective of the type of valve. Patients with HVR had a 2.5-fold risk of ≥ moderate post-TAVR AR compared to patients with LVR. Both, HVR (HR_adj 2.45, 95% CI 1.33-4.51) and the use of SE (HR_adj 3.11, 95% CI 1.66-5.82), emerged as independent predictors of ≥ moderate post-TAVR AR. Moderate or greater post-AR was consistently predicted in patients treated with SE (HR_adj 2.42, 95% CI 1.22-4.80) irrespective of the level of VR.

CONCLUSIONS

HVR is associated with a nearly 2.5-fold increased risk of moderate or greater post-TAVR AR and is an independent predictor of post-TAVR AR.

Transcatheter aortic valve implantation utilizing a non-occlusive balloon for predilatation

BACKGROUND

Balloon aortic valvuloplasty (BAV) is routinely performed preceding transcatheter aortic valve implantation (TAVI). Among risks inherent in BAV is low cardiac output due to rapid ventricular pacing (RVP), especially in patients with severely impaired left ventricular function. We herein report early experience utilizing a non-occlusive balloon for BAV (TrueFlow™, BARD, Peripheral Vascular, Tempe, AZ, US), which does not require RVP.

METHODS

Between 11/2016 and 10/2017, 27 consecutive patients received TAVI using a non-occlusive balloon valvuloplasty catheter for predilatation and a self-expandable transcatheter heart valve (77.8% female, 81.7 ± 6.6 years, logEuroSCORE I 15.8 ± 10.3%, STS Prom Score 2.5 ± 0.5%). Hemodynamic measurements and acute outcome data were analyzed according to updated Valve Academic Research Consortium definitions.

RESULTS

Procedure time, fluoroscopy time and amount of contrast agent were 74.5 ± 17.4 min, 16.7 ± 6.9 min and 156.9 ± 92.7 ml. Device success and early combined safety were 100% and 92.6% (25/27). Effective BAV without RVP after the first inflation was achieved in 92.6% of the patients (25/27). Continuous recording of hemodynamics documented no relevant systemic pressure drop during BAV. Postdilatation with a regular balloon was required in 10/27 patients. No death was observed during 30-day follow-up. Resultant mean transvalvular gradient was 6.0 ± 3.5 mm Hg. In one patient a moderate paravalvular leakage was seen.

CONCLUSIONS

In this series of TAVI utilizing a novel non-occlusive balloon, safety and efficacy were demonstrated. Adequate predilatation was achieved in all cases without need for RVP and with stable hemodynamics. These results will have to be confirmed in larger patient cohorts.

Spotlight on the SAPIEN 3 transcatheter heart valve

Transcatheter aortic valve implantation (TAVI) is increasingly performed in patients with severe aortic stenosis. The efficacy and safety have been demonstrated in large randomized trials in patients with high- or intermediate operative risk. With latest-generation transcatheter heart valve (THV) systems, growing operator experience and improved patient selection, clinical outcome has significantly improved with a decline of TAVI-related complications. In this review, the Edwards SAPIEN 3 THV is discussed in terms of technology, procedural advances and complication trends and future developments.

Imaging for structural heart procedures: focus on computed tomography

The success and continued rapid clinical integration of transcatheter valve technologies relies on imaging modalities to guide safe and effective device deployment. In particular, cardiac imaging, using both echocardiography and CT, is an integral resource for the multidisciplinary team. These modalities can provide valuable insight for the proceduralist at each stage of transcatheter-based valve insertion, as they can be used reliably to define the anatomy of interest and its relationship to surrounding structures, determine accurate device sizing, assess patients for valve-in-valve procedures, and screen for adverse features or procedural contraindications. We provide an overview of some of the key aspects of the use of CT and echocardiography in the context of transcatheter aortic valve replacement (TAVR), as well as transcatheter mitral valve replacement (TMVR).

Computed tomography predictors of mortality, stroke and conduction disturbances in women undergoing TAVR: A sub-analysis of the WIN-TAVI registry

BACKGROUND

Aortic valve calcification patterns were associated with short- and long-term outcomes in previous small observational datasets of patients undergoing transcatheter aortic valve implantation (TAVI). The specific impact of multi detector-row computed tomography (MDCT) findings on outcomes in women has not been reported. We sought to describe the associations between MDCT characteristics and clinical outcomes in a registry of 547 women undergoing TAVI.

METHODS

WIN-TAVI is the first all-female registry to study the safety and effectiveness of TAVI in women (n = 1019). Thirteen sites participated in the MDCT sub-study and contributed pre-TAVI MDCT studies in 547 consecutive subjects. All MDCT data were analyzed in an independent core lab blinded to clinical outcomes. Key measurements included number of valve leaflets, aortic annulus area and perimeter, left and right coronary artery height, aortic cusp calcium volume, commissural calcification and left ventricular outflow tract (LVOT) calcification. Calcium volume of the aortic valvular complex was quantified using a threshold relative to patient-specific contrast attenuation in the arterial blood pool. We examined univariate and multivariate associations between ECG-gated contrast MDCT characteristics and 1-year mortality or stroke, new pacemaker implantation and new onset atrial fibrillation (AF).

RESULTS

The CT sub-study sample had a mean age of 82.8 ± 6.3 years, mean logistic EuroSCORE of 17.8 ± 11.3%, and mean STS score of 8.2 ± 7.4%. Transfemoral access was used in 89.6% of patients. After multivariate adjustment, moderate or severe LVOT calcification was an independent predictor of 1-year mortality or stroke (HR = 1.91; 95% CI: 1.11-3.30; p = 0.02). Calcium volume in the right coronary cusp was an independent predictor of new pacemaker (HR = 1.18 per 100 m³ increment; p = 0.04), whereas calcium volume of the non-coronary cusp had a protective effect (HR = 0.78 per 100 mm³ increment; p = 0.004). Severe calcification of the non-coronary/right-coronary commissure was an independent predictor of new AF (HR = 5.1; p = 0.008).

CONCLUSION

Computed tomography provides important prognostic information in women undergoing TAVI. Moderate or severe LVOT calcification is associated to an almost two-fold increased risk of mortality or stroke at one year. Different calcification patterns of the aortic valve may predict diverse rhythm abnormalities.

Comparative analysis of balloon- versus mechanically-expandable transcatheter heart valves considering landing zone calcification

BACKGROUND

The balloon-expandable Sapien 3 (Edwards Lifesciences, Irvine, CA, USA) and the mechanically-expandable Lotus valve (Boston Scientific, Marlborough, MA, USA) are established devices for transcatheter aortic valve implantation. We sought to compare both transcatheter heart valves (THV) under consideration of the extent of THV landing zone calcification.

METHODS

This retrospective analysis includes consecutive patients with severe aortic stenosis treated with Sapien 3 (S3; n=212) or Lotus (n=61) THV via transfemoral access. Outcome was assessed according to VARC II definitions. Rate of paravalvular leakage (PVL), periprocedural stroke, and permanent pacemaker implantation (PPI) was adjusted for THV landing zone calcification as calculated by multi-slice computed tomography.

RESULTS

There was no difference in preoperative risk (all results as follows S3 vs. Lotus: STS-PROM 5.9±5.6% vs. 4.8±2.6%, p=0.14), rate of device success (95.3% vs. 95.1%, p=0.67), 30-day mortality (1.9% vs. 4.9%, p=0.16), periprocedural stroke (1.4% vs. 4.9%, p=0.27), and major access site complications (9.4% vs. 9.8%, p=0.93). PPI was more frequent (19.4% vs. 34.4%, p=0.01) and significant PVL was less frequent (≥mild PVL: 17.6% vs. 3.7%, p=0.04) after Lotus implantation. No association was found between landing zone calcification and periprocedural stroke rate (OR 1.19, 95%CI 0.92-1.54, p=0.17) or need for PPI (OR 1.04, 95%CI 0.91-1.18, p=0.57). The extent of landing zone calcification was associated with risk for PVL ≥mild (OR 1.21, 95%CI 1.03-1.42, p=0.02). After adjusting for landing zone calcification risk for PVL ≥mild was lower with the Lotus valve (OR 0.15, 95%CI 0.02-0.54, p=0.01).

CONCLUSION

Both THVs yield comparable procedural and clinical outcomes except for a higher PPI rate with the Lotus valve, which is independent from the extent of landing zone calcification. The extent of landing zone calcification is associated with an increased risk for PVL for both THV, but is significantly reduced with the Lotus valve.

Transcatheter aortic valve implantation using the ACURATE TA™ system: 1-year outcomes and comparison of 500 patients from the SAVI registries

OBJECTIVES: The ACURATE TA^TM system is a self-expanding transcatheter heart valve system designed for transapical access which has been proven to be safe and effective in the controlled setting of clinical trials. The SAVI-1 and SAVI-2 registries aimed to assess whether these promising outcomes can be translated into all-comers clinical routine.

METHODS: From November 2011 to 2012 (SAVI-1), and November 2013 to 2014 (SAVI-2), a total of 500 patients were enrolled in the prospective, all-comers, multicentre, multinational SAVI registries. Patients were treated according to the standard of care at their respective hospitals. We report and compare 30-day and 1-year clinical outcomes between SAVI-1 and -2.

RESULTS: Patients were 80.8 ± 6.1 years old, the mean logistic EuroSCORE-I was 23.4 ± 14.3%. Valves were deployed under rapid pacing in 71.3% of the procedures in SAVI-1, and in 3.6% in SAVI-2. There was no relevant difference in clinical and echocardiographic outcomes between SAVI-1 and SAVI-2. Overall mortality at 30 days and 1 year was 6.8% and 19.9%, the stroke rate was 2.2% and 3.7%, respectively; 10.2% of patients had received a permanent pacemaker, and no transcatheter valve-related complications after discharge were observed. Paravalvular leakage ≥2+ was reported in 1.9% of the patients at the early follow-up, and in 2.6% at the 1-year follow-up.

CONCLUSIONS: The SAVI-registries have confirmed that transapical implantation using the ACURATE TA^TM device is safe and effective in an all-comers setting with low complication rates and stable performance outcomes at short-term and 1 year; outcomes were similar between SAVI-1 and -2. ClinicalTrials.gov: NCT02663375

Relation Between Left Ventricular Outflow Tract Calcium and Mortality Following Transcatheter Aortic Valve Implantation

Left ventricular outflow tract (LVOT) calcium is known to be associated with adverse procedural outcomes after transcatheter aortic valve implantation (TAVI), yet its effect on midterm outcomes has not been previously investigated. The aim of this study was to determine the influence of LVOT calcium on 2-year mortality after TAVI. A total of 537 consecutive patients underwent TAVI and 2 groups were established, stratified based on the severity of the LVOT calcium. The primary outcome was 2-year overall survival rate. The ≥moderate LVOT calcium group included 107 patients (19.9%) and the remaining 430 patients (80.1%) were included in the ≤mild LVOT calcium group. After a median follow-up of 717 days (interquartile range 484 to 828), the Kaplan-Meier analysis revealed that the 2-year overall survival probability was significantly lower in the ≥moderate LVOT calcium group than in the ≤mild LVOT calcium group (log-rank p = 0.001). On a Cox hazard model, ≥moderate LVOT calcium was associated with increased all-cause mortality after TAVI (hazard ratio 1.74, p = 0.009). In the subgroup analysis, based on valve designs, SAPIEN 3-TAVI done in the setting of ≥moderate LVOT calcium had a relatively similar survival probability as those of ≤mild LVOT calcium (log-rank p = 0.18), which is in contrast with older generation valves (log-rank p = 0.001). In conclusion, patients with ≥moderate LVOT calcium were shown to have a lower survival probability in the midterm follow-up after TAVI, compared with those with ≤mild LVOT calcium. Patients with high-grade LVOT calcium should be monitored with longer-term follow-ups after TAVI.

Update on the significance of postprocedural aortic regurgitation after transcatheter aortic valve replacement on postprocedural prognosis

Transcatheter aortic valve replacement (TAVR) is an established therapy for patients with aortic stenosis and a high surgical risk. Recent data on intermediate-risk patients will probably enlarge the indication for TAVR. In the beginning of the TAVR era, relevant (>mild) aortic regurgitation (AR) was a common finding after TAVR; it was associated with worse outcome compared with patients without significant AR. To date, several improvements in imaging, grading of severity and treatment have been done and will be discussed in this article. AR after TAVR still is a strong and independent predictor of 1-year mortality and every effort should be made to prohibit its development.

Comparison of outcomes using balloon-expandable versus self-expanding transcatheter prostheses according to the extent of aortic valve calcification

BACKGROUND

Device landing zone (DLZ) calcification is an important determinant of procedural success in transcatheter aortic valve implantation (TAVI).

OBJECTIVE

To evaluate the impact of DLZ calcification on procedural outcome with different types of transcatheter heart valves (THVs).

METHODS

Aortic valve calcium density (AVC_dens) was determined by non-contrast-enhanced computed tomography in 1232 patients undergoing transfemoral TAVI. We stratified the outcome data according to the extent of AVC_dens (mild, moderate, severe) and compared balloon-expandable (BE) with self-expanding (SE) THV. Moreover, THVs were subdivided according to their radial force (BE: high; SE_mod: moderate; SE_low: low).

RESULTS

With BE THV, PVR ≥2° (2.1 vs. 7.9%; p < 0.001), post-dilatation (12.3 vs. 36.6%; p < 0.001), malpositioning (8.4 vs. 13.0%; p = 0.01), device embolization (0.4 vs. 2.6%; p = 0.004), and the need for a second valve (1.2 vs. 3.6%; p = 0.01) were less frequent than with SE devices, but mean transaortic gradients at discharge were higher [12.0 mmHg (8.0-15.0) vs. 9.0 mmHg (6.0-11.0); p < 0.001], and aortic root injury was more frequent (2.7 vs. 0.8%; p = 0.01). In cases of severe calcification, differences between BE and SE THV regarding PVR, post-dilatation, and hemodynamics were mostly pronounced, followed by patients with moderate AVC_dens. In cases with low AVC_dens, the best outcomes with respect to PVR, pacemaker implantation, and hemodynamics were achieved with SE_low THV.

CONCLUSIONS

In severe and moderate DLZ calcification, BE devices may have advantages, whereas in mild DLZ calcification, SE_low THV showed the most favorable profile.

First experience with transfemoral transcatheter aortic valve implantation without prior balloon pre-dilatation using a latest generation repositionable and retrievable transcatheter heart valve†

OBJECTIVES

: The aim of this study was to prove technical feasibility and document haemodynamic and clinical outcomes of transcatheter aortic valve implantation (TAVI) with the latest generation repositionable and retrievable Lotus™ transcatheter heart valve (THV) without prior balloon-aortic valvuloplasty (BAV). It has been demonstrated for self-expandable and balloon-expandable THV that implantation without prior BAV is not only feasible and safe but also results in lower fluoroscopy times and amounts of contrast agent while yielding non-inferior haemodynamic and clinical outcome. To date no reports exist for TAVI without BAV for the Lotus™ THV.

METHODS

: A consecutive patient series received direct transfemoral (TF)-TAVI without prior BAV using the Lotus™ valve system. Baseline, intraprocedural and acute follow-up data up to 30 days were retrospectively collected. Clinical endpoints were adjudicated in accordance with the updated standardized Valve Academic Research Consortium (VARC)-2 definitions.

RESULTS

: A total of 9 patients received direct TF-TAVI using the Lotus THV (77.7% female, 82.5 ± 5.3 years, logistic European System for Cardiac Operative Risk Evaluation I 14.2 ± 13.7%). Device success according to VARC-2 definitions was achieved in 100% (9/9) of the patients. Peak and mean transvalvular gradients as determined by transthoracic echocardiography prior to discharge decreased from 51.5 ± 17.3 to 24.4 ± 10.4 mmHg and 29.5 ± 9.6 to 13.2 ± 5.2 mmHg (both P  <   0.01). Effective orifice area increased from 0.9 ± 0.2 to 1.9 ± 0.3 cm 2 ( P  <   0.01). No paravalvular leakage (PVL) ≥ moderate was detected. All-cause 30-day mortality was 11.1% (1/9), with one death due to ischaemic enteritis.

CONCLUSIONS

: In our series, TF-TAVI without prior BAV using this particular THV technical feasibility, no increased incidence of significant paravalvular leakage, and good haemodynamic and clinical outcome in selected patients. These results will have to be confirmed in larger patient numbers for further clinical evaluation and before general recommendations regarding patient selection can be made.

Dual source computed tomography based analysis of stent performance, its association with valvular calcification and residual aortic regurgitation after implantation of a balloon-expandable transcatheter heart valve

Objectives

The aim of this study was to investigate the mutual influence of valvular calcifications and transcatheter aortic valve stent geometry during and after implantation of a balloon-expandable SAPIEN ® /SAPIEN XT ® prostheses. Aortic valve calcification has been linked with adverse complications after transcatheter aortic valve implantation (TAVI). However, little is known about the fate of the calcifications after TAVI as well as its influence on transcatheter heart valve geometry.

Methods

Thirty one patients underwent cardiac dual source computed tomography (DSCT) before and after a TAVI with the Edwards SAPIEN/SAPIEN XT ® prostheses. Detailed DSCT image analysis was performed with Mimics ® and 3Matic ® (both Materialise, Leuven, Belgium).

Results

Implanted stents reached an average degree of expansion of 84% and achieved good circularity despite the presence of fairly oval native annuli and a heterogeneous degree of valvular calcification. Both, the degree of stent expansion and the degree of stent eccentricity were inversely related to the degree of oversizing, but independent of the degree of valvular calcification and native annular ovality. Visualization of the position of calcific debris before and after TAVI showed that calcifications were shifted upwards and outwards as a consequence of the implantation procedure. The degree of stent eccentricity was related to residual aortic regurgitation grade ≥2.

Conclusions

The SAPIEN ® /SAPIEN XT ® prostheses achieved good degrees of stent expansion and circularity regardless of the morphology of the landing zone. Increased stent ovality was associated with an elevated risk for aortic regurgitation. The total calcification volume, degree of annular ovality and stent expansion were not associated with residual AR.

Predilatation Prior to Transcatheter Aortic Valve Implantation: Is it Still a Prerequisite?

Predilatation has been historically considered a mandatory step before transcatheter aortic valve implantation (TAVI) since it facilitates valve crossing and prosthesis delivery, ensures optimal valve expansion and improves hemodynamic stability during valve deployment. However, as a result of procedural evolution over time, direct TAVI (without pre-implantation balloon aortic valvuloplasty) has emerged as an interesting option to simplify the procedure and to avoid potential valvuloplasty-related complications. Several real-world retrospective studies and one small randomised study have shown that direct TAVI (with both self-expanding and balloon-expandable prostheses) is feasible, safe and associated with outcomes similar to standard TAVI with pre-implantation balloon aortic valvuloplasty. In the absence of high-quality, robust evidence, the current review aims to discuss the advantages and disadvantages of omitting predilatation prior to TAVI.

Impact of Different Iterations of Devices and Degree of Aortic Valve Calcium on Paravalvular Regurgitation After Transcatheter Aortic Valve Implantation

The iterations of the SAPIEN prosthesis might impact the incidence and grade of paravalvular regurgitation (PVR). The aim of this study was to assess the impact of iterations of balloon-expandable valves (SAPIEN, SAPIEN XT, and SAPIEN 3) and degree of aortic valve calcification (AVC) on the severity of PVR after transcatheter aortic valve implantation (TAVI). Comprehensive echocardiographic examinations and multidetector computed tomography (MDCT) were performed in 272 patients (127 men, 81 ± 7 years old, logistic EuroScore of 21 ± 13%) who underwent TAVI with 23- and 26-mm balloon-expandable valves. The degree of AVC was assessed with MDCT. PVR grade was assessed with echocardiography. The cover index was calculated as (prosthesis area - MDCT annulus area)/prosthesis area. SAPIEN, SAPIEN XT, and SAPIEN 3 prostheses were implanted in 103 patients (38%), 105 patients (38.5%), and 64 patients (23.5%), respectively. Significant PVR (≥moderate) occurred in 14%, 10%, and 0% of patients receiving the SAPIEN, SAPIEN XT, and SAPIEN 3, respectively (p = 0.010). Across the groups, the aortic annulus size, degree of calcification, and cover index were comparable. Larger burden of AVC was independently associated with significant PVR (odds ratio 3.48, p = 0.006) after adjusting for age, body surface area, gender, aortic annulus area, cover index, and prosthesis iteration. SAPIEN 3 was associated with lower frequency of significant PVR (odds ratio 0.31, p = 0.002). In conclusion, the incidence of significant PVR significantly decreased over time with improvement in valve design. SAPIEN 3 was associated with less significant PVR after TAVI independently of the AVC burden.

An up-to-date overview of the most recent transcatheter implantable aortic valve prostheses

Over the past decade transcatheter aortic valve implantation (TAVI) has evolved towards the routine therapy for high-risk patients with severe aortic valve stenosis. Technical refinements in TAVI are rapidly evolving with a simultaneous expansion of the number of available devices. This review will present an overview of the current status of development of TAVI-prostheses; describes the technical features and applicability of each device and the clinical data available.