C31 UPDATE ON SUPRA–ANNULAR SIZING OF TRANSCATHETER AORTIC VALVE PROSTHESES IN RAPHE–TYPE BICUSPID AORTIC VALVE DISEASE ACCORDING TO THE LIRA METHOD

Aims

Recent evidences have shown that transcatheter heart valve (THV) anchoring in BAV patients might occur at the raphe–level, known as the LIRA (Level of Implantation at the RAphe) plane. A novel supra–annular sizing method based on the measurement of the perimeter at the raphe–level (LIRA–method) was shown to be safe and effective in 20 consecutive BAV patients with severe aortic stenosis. The purpose of this study was to confirm the safety and the efficacy of the LIRA method in a larger study population.

Methods

the LIRA plane method was applied to all consecutive patients with raphe–type BAV disease between November 2018 to October 2021 in our centre. We prospectively sized TAVI prosthesis according to the manufacture recommendations on the basis of baseline CT scan perimeters at the LIRA plane. Post–procedural device success, defined according to Valve Academic Research Consortium–2 (VARC–2) criteria, was evaluated in the overall cohort.

Results

50 patients were identified as having a raphe–type BAV disease at pre–TAVI CT scans. Mean patient age was 80 ± 6.2 years. Three different BAV anatomies (47 patients with BAV type 1 and 3 patients with BAV type 2) were implanted with different types of TAVI prostheses (28 Acurate Neo/Neo 2, 21 Core Valve Evolut R/Pro,1 Lotus) sized prospectively according to the LIRA plane method. In all patients, there was a significant discrepancy between LIRA and virtual basal ring (VBR) (mean perimeter LIRA 73.1 ± 8.3 mm vs mean perimeter VBR 81.5 ± 6.6 mm; p < 0.001). The median prosthesis size was 26 mm (23–27). Pre–dilatation was frequently performed (88%) with a median balloon size of 20 mm (20–23), whereas post–dilatation was applied in 26% of the cases with a median balloon size of 23 mm (22–24). The LIRA plane method appeared to be highly successful (100% VARC–2 device success) with no procedural mortality, no valve migration, residual trivial/mild paravalvular leak with no cases of moderate–severe regurgitation and no cases of mean gradient >20 mmHg pre–discharge. The rate of new pacemaker implantation was 10%.

Conclusions

Supra–annular sizing according to the LIRA plane method confirmed to be safe with a high device success in a larger study population. The application of the LIRA plane method might optimize TAVI prosthesis sizing in patients with raphe–type BAV disease.

Multiparametric assessment of the intraprocedural result after transcatheter mitral valve edge-to-edge repair proceduret

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Research grant

OnBehalf

n/a

Background. Quantification of residual mitral regurgitation (MR) after transcatheter edge-to-edge mitral valve repair (TMVr) is challenging.

Objectives.  To evaluate the feasibility and the performance of an intraprocedural multiparametric approach based on echocardiographic and invasive hemodynamic parameters and to develop a multiparametric scoring system for MR grading after TMVr, and to compare this approach against currently recommended methods. 

Methods. Ninety-three consecutive patients treated with MitraClip (April 2019-July 2020) were enrolled. The protocol of MR evaluation included: 2D and 3D color-Doppler (3D-vena contracta area- 3D-VCA), pulsed-wave Doppler (pulmonary vein- PV flow, stroke volume), continuous-wave Doppler (jet density), morphological parameters (spontaneous echocontrast) and invasive hemodynamic (mean left atrial pressure-LAP, V-wave) at baseline and after clip implantation. A multiparametric score (M-score) was calculated by including the significant predictors (3D-VCA, dense jet on CWD, final LAP, final V wave) of primary endpoint (CV death or HF related hospitalization) at one year follow-up, weighted according to the corresponding odds ratio, to predict the clinical outcome at one-month and one-year follow-up. 

Results. The final study population included 86 pts (mean age 78.3 +8.9yrs, 54.6% primary MR). Procedural success was achieved in 78 pts (90.7%). 3D-VCA (AUC 0.808) and current method for MR grading (AUC 0.801) were comparable predictors of lack of symptom improvement (<5 point change in KCCQ-OS score) at one-month (p = 0.398, DeLong’s test). The M-score performed similarly as predictor of one-month follow-up but was a better predictor of primary endpoint at 1-year (AUC 0.919) compared to single parameters (p = 0.005 vs 3D-VCA DeLong"s test) and currently recommended methods for MR grading (p = 0.006 DeLong"s test). The optimal cut-off was 2 points with 86.7% sensitivity and 83.1% specificity.

Conclusion. We evaluated intraprocedural TMVr result in a multiparametric approach showing that 3D-VCA alone is comparable to current recommended method for MR grading. However, the integration of echocardiographic and invasive hemodynamic parameters into a multiparametric score provided a further added value for predicting clinical outcome  at one-year compared to currently recommended methods for MR grading and to 3D-VCA.

428 Prognostic implications of the relationship between effective regurgitant orifice area and left ventricle end diastolic volume in patients with functional mitral regurgitation treated with MitraClip

Funding Acknowledgements

none

Background

The distinction between proportionate and disproportionate functional mitral regurgitation (FMR), based on the relationship between effective regurgitant orifice area (EROA) and left ventricle end diastolic volume (LVEDV), has recently been proposed as a possible new clinical and physiopathological framework to identify patients that could likely benefit from transcatheter mitral repair.

Purpose The aim of our study was to explore the possible prognostic implications of the EROA/LVEDV ratio in patients with FMR treated with MitraClip.

Methods – Baseline EROA/LVEDV was calculated in 137 patients with at least moderate-to-severe, symptomatic FMR treated with MitraClip. All patients underwent clinical, biochemichal and echocardiographic evaluation before MitraClip. EROA was calculated using PISA method. The primary outcome was a composite end-point of all-cause death or re-hospitalization for heart failure (HF).

Results – The median follow-up was 1.1 years. The primary outcome occurred in 59 patients (43 %). Population study showed a LVEDVi 113.52± 32.16 mL/m2, LVEF 29.75± 10.06% and EROA 39.45± 15.43 mm2.. The cut-off value of EROA/LVEDV ratio for primary outcome, identified by receiver operating characteristic curve, was 0.15 (AUC 0,65, p = 0.002) with a sensitivity and specificity of 78% and 52%, respectively. Patients were divided in two groups according to the identified cut-off. Patients with higher ratio (Group I, n = 88) presented a less dilated LV (LVEDVi: 105.1 ± 29.6 mL/m2 vs 128.2 ± 31.9 mL/m2, p < 0.001; LVESVi: 73.1 ± 27.7 mL/m2 vs 94.9 ± 29.05 mL/m2, p < 0.001), and a more severe MR (EROA: 47.9 ± 12.1 mm2 vs 25.1 ± 8.3 mm2, p < 0.001; vena contracta: 7.2 ± 1.3 mm vs 6.5 ± 1.3 mm, p = 0.008). There were no significant differences of left ventricle ejection fraction, right ventricle systolic function and systolic pulmonary pressure between the groups. At univariate analysis, EROA/LVEDV ratio >0.15 (HR = 2.223, 95% CI 1.121-4.411, p = 0.022), baseline evidence of atrial fibrillation (HR = 1.949, 95% CI 1.156-3.283, p = 0.012) and baseline pro-BNP (HR= 1.000, 95% CI 1.000-1.000, p = 0,001) were associated with a worse clinical outcome. At multivariate Cox-regression analysis, both EROA/LVEDV ratio >0.15 and baseline pro-BNP values were identified as independent predictors (HR 2.941, 95% CI 1.035-8.353, p = 0.043; HR = 1.000, 95% CI 1.000-1.000, p = 0.002, respectively). At Kaplan-Meier survival analysis, patients with EROA/LVEDV >0.15 had a significant lower freedom from composite endpoint (log-rank χ2 =5.517, p= 0.019; Fig. 1).

Conclusion

Our data show that EROA/LVEDV ratio was an independent predictor of adverse clinical outcome in FMR patients treated with MitraClip. This preliminary experience shows that this index could help to identify subgroups of patients with potential different clinical benefits from Mitraclip therapy. However, further and extended data are needed to provide more precise evidence.

Abstract 428 Figure. Fig. 1

P43673D analysis of mitral annular reshape with third generation MitraClip XTr in functional and degenerative mitral regurgitation

The 3rd generation Mitraclip XTr was recently introduced to improve device performance, through longer clip arms that should allow better grasping of the mitral leaflets, thus improving coaptation and results eventually. Several studies have demonstrated additional effects such as the reshape of the mitral annulus immediately after clip implantation.

The aim of our study was to evaluate the mitral valve (MV) annular remodelling with MitraClip XTr.

Between March 2018 and November 2018, 75 consecutive patients were enrolled. The population was divided in two groups: functional mitral regurgitation (FMR) and degenerative mitral regurgitation (DMR).

The 3D MV datasets at baseline and immediately after the procedure were acquired and then analysed with semiautomatic MVQ software (QLAB Cardiac 3DQ v.10.0; Philips Medical Systems).

The software provides the following parameters: annular diameters (antero-posterior, AP, and inter-commissural, IC), circumference, area, height and ellipsicity (IC/AP ratio as percentage); saddle-index, defined as annular height to IC diameter ratio was derived.

The 3D post-processing was feasible in 54 patients (108 3D datasets): 28 had FMR (52%) and 26 had DMR (48%).

An average of 1.8 clips per patient were implanted: 2 clips in 38 (70%), 1 clip in 14 (26%) and 3 clips in 2 (4%) patients. The position was central in 93% of the procedures.

Results are reported in table 1. In the FMR group, a reduction in the AP diameter (p=0.001), an increase in both IC diameter (p=0.001) and annular ellipsicity (p<0.001) were observed.

In the DMR group, an increase in annular ellipsicity (p=0,008) and in saddle-index (p<0.05) were observed.

Table 1 Functional mitral regurgitation (N=28) Degenerative mitral regurgitation (N=26) Pre-clip Post-clip P-value Pre-clip Post-clip P-value IC diameter (mm) 39.3±4.2 41.9±4.1 0.001 40.9±6.5 41.8±5.8 0.257 AP diameter (mm) 32.8±4.6 30.4±3.2 0.001 32.6±4.8 31.7±4.5 0.199 Annular Height (mm) 5.1±1.8 5.4±1.8 0.336 4.8±1.9 5.7±2.2 0.026 3D circumference (mm) 122.7±15.1 123.5±11 0.718 123.5±19.0 124.0±17.1 0.812 3D area (mmq) 1128.0±280 1113.7±206 0.752 1160±346.7 1156.8±318.0 0.926 Annular ellipsicity (%) 121.5±12.2 138.5±11.8 0.0005 125.9±9.6 132.4±10.7 0.008 Saddle index 13.0±4 13.0±4 0.957 11.8±4.2 13.6±4.2 0.048

Our study demonstrates that the XTr implantation produces a MV annular remodelling both in FMR and DMR probably with different mechanisms. In FMR the MV annulus resulted more elliptical, wheras in DMR the geometrical modifications involve both the ellipsicity and the saddle-shape morphology.

P4728Prognostic implications of the relationship between effective regurgitant orifice area and left ventricle end diastolic volume in patients with functional mitral regurgitation treated with MitraClip

Background

The distinction between proportionate and disproportionate functional mitral regurgitation (FMR), based on the relationship between effective regurgitant orifice area (EROA) and left ventricle end diastolic volume (LVEDV), has recently been proposed as a possible new clinical and physiopathological concept to identify patients that could likely benefit from transcatheter mitral repair.

Purpose

The aim of our study was to explore the possible prognostic implications of the EROA/LVEDV ratio in patients with FMR treated with MitraClip.

Methods

Baseline EROA/LVEDV ratio was calculated in 72 patients with moderate-to-severe, symptomatic FMR treated with MitraClip. All patients underwent clinical, biochemichal and echocardiographic evaluation before MitraClip. EROA was calculated using PISA method. The primary outcome was a composite end-point of all-cause death or re-hospitalization for heart failure (HF).

Results

The median follow-up was 1 year. The primary outcome occurred in 25 patients (34.7%). The cut-off value of EROA/LVEDV ratio for primary outcome, identified by receiver operating characteristic curve, was 0.15 (p=0.007) with a sensitivity and specificity of 72 and 68%, respectively. Patients were divided in two groups according to the identified cut-off. Patients with higher ratio (Group I, n=35) presented a less dilated LV (LVEDVi: 113.2±33.4 mL vs 129.3±29.3 mL, p=0.033; LVESV: 140.7±49.0 mL vs 171.1±47.4 mL, p=0.010), a better LV systolic function (LVEF: 31.9±9.5% vs 27.8±5.8%, p=0.028) and a more severe MR (EROA: 44.5±12.9 mm2 vs 24.5±6.8 mm2, p<0.001; vena contracta: 7.4±1.5 mm vs 6.7±1.0 mm, p=0.045). Patients with lower ratio (Group II, n=37) showed a reduced prevalence of MV annular dilation (57.1% vs 91.7%, p=0.005) and a worse RV function (s'TDI: 9.2±2.2 cm/s vs 10.5±2.9 cm/s, p=0.039). At univariate analysis, EROA/LVEDV ratio >0.15 (HR = 2.467, 95% CI 1.017–5.982, p=0.046) and severe pulmonary hypertension (HR = 2.481, 95% CI 1.030–5.976, p=0.043) were associated with a worse clinical outcome. At multivariate Cox-regression analysis, both EROA/LVEDV ratio >0.15 and severe pulmonary hypertension were identified as independent predictors (HR 3.203, 95% CI 1–310–7.832, p=0.011; HR = 3.280, 95% CI 1.326–8.116, p=0.010, respectively).

Figure 1

Conclusion

Our data show that EROA/LVEDV ratio was an independent predictor of adverse clinical outcome in FMR patients treated with MitraClip. This preliminary experience shows that this index could help to identify subgroups of patients with potential different clinical benefits from MitraClip therapy. However, further and extended data are needed to provide more precise evidence.

Acknowledgement/Funding

None

Review of the MitraClip clinical evidence

MitraClip system is the only catheter-based device for percutaneous mitral valve repair available for clinical use, after receipt of the CE Mark in 2008, while it is currently under review for FDA approval in the US. To date, over 3500 MitraClip implants have been performed worldwide, mainly in high risk surgical patients. The aim of this review is to review all the current evidences of the MitraClip therapy in an aim to define its clinical role in the treatment of mitral regurgitation (MR).

Patient selection for MitraClip therapy impaired left ventricular systolic function

Mitral regurgitation (MR) is a disabling disease associated with poor prognosis and high incidence of clinical events if left untreated. To reduce the invasiveness of the surgical approach, different types of transcatheter procedures are becoming available. The MitraClip procedure (Abbott Vascular Inc. Menlo Park, CA, USA) is yet the only catheter-based procedure available in clinical practice at the moment. The device has been evaluated in a number of preclinical studies, registries and in FDA approved clinical trials. (EVEREST trial, ACCESS-EU trial). Indication and timing of intervention is a crucial step in the diagnostic-therapeutic pathway of patients with mitral regurgitation. The aim of this review is to clarify the potential of MitraClip in clinical practice, particularly focusing on patient selection for this novel therapy. Patient selection and overall decision making is strongly influenced by anatomical and clinical factors. Decision-making in degenerative MR (DMR) vs. functional (FMR) can be quite different. Generally, MitraClip is effective in treating either type II or IIIb dysfunction (at the moment FMR is the main indication for MitraClip in Europe, according to the ACCESS registry data). The relative role of MitraClip and surgery in the management of patients with MR is still unclear. From the global initial experience, MitraClip therapy could be complementary to surgery in those patients at high risk for surgery who have ideal anatomical characteristics for implantation. The procedure is quite predictable in patients with favorable anatomy. In patients with suboptimal anatomy, if the risk of surgery is too high, MitraClip could be still indicated sometimes. Our preliminary experience suggests that in patients with DMR, the EVEREST anatomical criteria are strong predictors of early and mid-term success. According to it, MitraClip therapy is appropriate in those DMR patients with high surgical risk and ideal anatomy for clip implantation according to the EVEREST criteria. In FMR refractory to medical therapy and resynchronization therapy, MitraClip could be considered as first option therapy, particularly in those patients with comorbidities, or advanced age, being the operative risk of surgery above 5% in this population. In the future, novel devices, improved knowledge, more efficient imaging and transcatheter mitral prosthetic valve implantation may expand the indications to those patients currently not treated by MitraClip for anatomical unsuitability, and may improve the results both in term of early efficacy and long term durability.