The best way to transcatheter aortic valve implantation: From standard to new approaches

Procedural success in transaxillary transcatheter aortic valve implantation according to type of transcatheter heart valve: results from the multicenter TAXI registry

BACKGROUND

Transaxillary (TAx) transcatheter aortic valve implantation (TAVI) is a preferred alternative access in patients ineligible for transfemoral TAVI.

AIMS

This study used the Trans-AXillary Intervention (TAXI) registry to compare procedural success according to different types of transcatheter heart valves (THV).

METHODS

For the TAXI registry anonymized data of patients treated with TAx-TAVI were collected from 18 centers. Acute procedural, early and 1-month clinical outcomes were adjudicated in accordance with standardized VARC-3 definitions.

RESULTS

From 432 patients, 368 patients (85.3%, SE group) received self-expanding (SE) THV and 64 patients (14.8%, BE group) received balloon-expandable (BE) THV. Imaging revealed lower axillary artery diameters in the SE group (max/min diameter in mm: 8.4/6.6 vs 9.4/6.8 mm; p < 0.001/p = 0.04) but a higher proportion of axillary tortuosity in BE group (62/368, 23.6% vs 26/64, 42.6%; p = 0.004) with steeper aorta-left ventricle (LV) inflow (55° vs 51°; p = 0.002) and left ventricular outflow tract (LVOT)-LV inflow angles (40.0° vs 24.5°; 0.002). TAx-TAVI was more often conducted by right sided axillary artery in the BE group (33/368, 9.0% vs 17/64, 26.6%; p < 0.001). Device success was higher in the SE group (317/368, 86.1% vs 44/64, 68.8%, p = 0.0015). In logistic regression analysis, BE THV were a risk factor for vascular complications and axillary stent implantation.

CONCLUSIONS

Both, SE and BE THV can be safely used in TAx-TAVI. However, SE THV were more often used and were associated with a higher rate of device success. While SE THV were associated with lower rates of vascular complications, BE THV were more often used in cases with challenging anatomical circumstances.

Features and outcomes of bailout repeat transcatheter aortic valve implantation (TAVI): the Bailout Acute TAVI-in-TAVI to Lessen Events (BATTLE) international registry

AIM

Transcatheter aortic valve implantation (TAVI) is a mainstay in the management of severe aortic stenosis in patients with intermediate to prohibitive surgical risk. When a single TAVI device fails and cannot be retrieved, TAVI-in-TAVI must be performed acutely, but outcomes of bailout TAVI-in-TAVI have been incompletely appraised. We aimed at analyzing patient, procedural and outcome features of patients undergoing bailout TAVI-in-TAVI in a multicenter registry.

METHODS

Details of patients undergoing bailout TAVI-in-TAVI, performed acutely or within 24 h of index TAVI, in 6 international high-volume institutions, were collected. For every case provided, 2 same-week consecutive controls (prior TAVI, and subsequent TAVI) were provided. Outcomes of interest were procedural and long-term events, including death, myocardial infarction, stroke, access site complication, major bleeding, and reintervention, and their composite (i.e. major adverse events [MAE]).

RESULTS

A total of 106 patients undergoing bailout TAVI-in-TAVI were included, as well as 212 controls, for a total of 318 individuals. Bailout TAVI-in-TAVI was less common in younger patients, those with higher body mass index, or treated with Portico/Navitor or Sapien devices (all p < 0.05). Bailout TAVI-in-TAVI was associated with higher in-hospital rates of death, emergency surgery, MAE, and permanent pacemaker implantation (all p < 0.05). Long-term follow-up showed that bailout TAVI-in-TAVI was associated with higher rates of death and MAE (both < 0.05). Similar findings were obtained at adjusted analyses (all p < 0.05). However, censoring early events, outlook was not significantly different when comparing the two groups (p = 0.897 for death, and p = 0.645 for MAE).

CONCLUSIONS

Bail-out TAVI-in-TAVI is associated with significant early and long-term mortality and morbidity. Thus, meticulous preprocedural planning and sophisticated intraprocedural techniques are of paramount importance to avoid these emergency procedures.

Acquired Thrombocytopenia in Contemporary Transcatheter Aortic Valve Prosthesis

BACKGROUND

 Postprocedural thrombocytopenia is a known phenomenon following transcatheter aortic valve implantation (TAVI). The aim of this study is to evaluate whether postinterventional platelet kinetics differ when comparing the current generation of balloon-expandable valve (BEV) and self-expanding valve (SEV) prostheses.

METHODS

 We performed a retrospective analysis of patients undergoing TAVI at our facility between 2017 and 2019. Patients were stratified according to the type of prosthesis used: BEV or SEV. Hematocrit-corrected platelet counts were calculated to account for dilution. Nadir platelet counts (lowest recorded platelet count), drop platelet counts (DPC; highest relative platelet drop from baseline), and severity of thrombocytopenia during the discourse and at discharge were assessed.

RESULTS

 Of the 277 included patients, 212 received SEV and 65 BEV. BEV patients were younger (81.8 ± 4.4 years vs 79.7 ± 6.8 years, p = 0.03). Further demographic characteristics were similar between groups. Implanted SEV were larger (p < 0.001) and had shorter procedural times (p < 0.01). There were no significant differences in postprocedural discourse. Postinterventional platelet drop was more pronounced in BEV patients in several evaluated metrics: mean DPC (24.3 ± 10.9% vs 18.8 ± 14.8%, p < 0.01), patients with DPC > 30% (n = 19, 29.2%, vs n = 33, 15.6%, p = 0.02), and also when comparing platelet kinetics.

CONCLUSION

 Despite improvements in outcome, the current generation of balloon-expandable TAVI prostheses carries a predisposition for postprocedural thrombocytopenia even when the effects of dilution are accounted for.

Prognostic Impact of Mitral Regurgitation Before and After Transcatheter Aortic Valve Replacement in Patients With Severe Low-Flow, Low-Gradient Aortic Stenosis

Background There is little evidence about the prognostic role of mitral regurgitation (MR) in patients with low-flow, low-gradient aortic stenosis undergoing transcatheter aortic valve replacement (TAVR). The aim of this study was to assess the prevalence and outcome implications of MR severity in patients with low-flow, low-gradient aortic stenosis undergoing TAVR, and to evaluate whether MR improvement after TAVR could influence clinical outcome. Methods and Results This study included consecutive patients with low-flow, low-gradient aortic stenosis undergoing TAVR at 2 Italian high-volume centers. The study population was categorized according to the baseline MR severity and to the presence of MR improvement at discharge. The primary outcome was the composite of all-cause death and hospitalization for worsening heart failure up to 1 year. The study included 268 patients; 57 (21%) patients showed MR >2+. Patients with MR >2+ showed a lower 1-year survival free from the primary outcome (P<0.001), all-cause death (P<0.001), and heart failure hospitalization (P<0.001) compared with patients with MR ≤2+. At multivariable analysis, baseline MR >2+ was an independent predictor of the primary outcome (P<0.001). Among patients with baseline MR >2+, MR improvement was reported in 24 (44%) cases after TAVR. The persistence of MR was associated with a significantly reduced survival free from the primary outcome, all-cause death, and heart failure hospitalization up to 1 year. Conclusions In this study, the presence of moderately severe to severe MR in patients with low-flow, low-gradient aortic stenosis undergoing TAVR portends a worse clinical outcome at 1 year. TAVR may improve MR severity in nearly half of the patients, resulting in a potential outcome benefit after discharge.

Fluoroscopically guided vascular and cardiac transcatheter procedures: a comparison of occupational and patient dose by anatomical region

X-ray guided procedures are being performed by an increasing variety of medical specialties. Due to improvements in vascular transcatheter therapies, there is an increasing overlap of imaged anatomy between medical specialties. There is concern that non-radiology fluoroscopic operators may not have sufficient training to be well informed of the potential implications of radiation exposure and mitigation strategies to reduce dose. This was a prospective, observational, single center study to compare occupational and patient dose levels when imaging different anatomical regions during fluoroscopically guided cardiac and endovascular procedures. Occupational radiation dose was measured at the level of the temple of 24 cardiologists and 3 vascular surgeons (n = 1369), 32 scrub nurses (n = 1307) and 35 circulating nurses (n = 885). The patient dose was recorded for procedures (n = 1792) performed in three angiography suites. Abdominal imaging during endovascular aneurysm repair (EVAR) procedures was associated with a comparatively high average patient, operator and scrub nurse dose despite additional table-mounted lead shields. Air kerma was relatively high for procedures performed in the chest, and chest + pelvis. Higher dose area product and staff eye dose were recorded during procedures of the chest + pelvis due to the use of digital subtraction angiography to evaluate access route prior to/during transaortic valve implantation. Scrub nurses were exposed to higher average radiation levels than the operator during some procedures. Staff should be cognizant of the potentially higher radiation burden to patients and exposed personnel during EVAR procedures and cardiac procedures using digital subtraction angiography.

Transcatheter aortic valve implantation with Allegra: procedural and mid-term outcomes according to experience phase in a high-volume center

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has revolutionized the management of aortic stenosis. We aimed at appraising effectiveness of a new self-expandable TAVI device.

METHODS

We retrospectively analyzed our institutional experience with Allegra (Biosensors, Morges, Switzerland) for TAVI, focusing on procedural outcomes and 1-month adverse events. We explored the impact of operator experience with this device, dividing patients according to their time of intervention.

RESULTS

Between 2018 and 2021, a total of 50 patients underwent TAVI with Allegra, with average age of 81 years, 80% women, and 50% at low or intermediate surgical risk. No major significant difference in baseline patient features were found when comparing Phase 1 and Phase 2, except for baseline left ventricular ejection fraction and New York Heart Association, which were worse in Phase 1. All procedures were performed transfemorally and percutaneously, with predilation in 94% and postdilation in 36%, yielding device success in 98%, and procedural success in 96%. No significant differences in procedural features were found when comparing Phase 1 vs. Phase 2 (all P>0.05). One-month follow-up was also favorable, with no significant difference in adverse outcomes according to phase, and a total of 1 (4%) death, 1 (4%) myocardial infarction, 1 (4%) minor vascular complication, and 4 (8%) permanent pacemaker implantations. Consistent findings were obtained at exploratory 6-month follow-up.

CONCLUSIONS

The Allegra TAVI device is associated with favorable short-to-midterm outcomes in experienced hands. Operators already proficient with other devices can achieve satisfactory results even in the early phase of adoption of Allegra.

TAVI-CT score to evaluate the anatomic risk in patients undergoing transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) requires thorough preprocedural planning with non-invasive imaging, including computed tomography (CT). The plethora of details obtained with thoraco-abdominal CT represents a challenge for accurate and synthetic decision-making. We devised and tested a comprehensive score suitable to summarize CT exams when planning TAVI. An original comprehensive scoring system (TAVI-CT score) was devised, including details on cardiac, aortic, iliac and femoral artery features. The score was applied to a prospectively collected series of patients undergoing TAVI at our institution, driving decision making on access and prosthesis choice. Different TAVI-CT score groups were compared in terms of procedural success, acute complications, and early clinical outcomes. We included a total of 200 undergoing TAVI between February 2020 and May 2021, with 74 (37.0%) having a low (0–2) TAVI-CT score, 50 (25.0%) having a moderate (3) TAVI-CT score, and 76 (38.0%) having a high (≥ 4) TAVI-CT score. Male gender was the only non-CT variable significantly associated with the TAVI-CT score (p = 0.001). As expected, access choice differed significantly across TAVI-CT scores (p = 0.009), as was device choice, with Portico more favored and Allegra less favored in the highest TAVI-CT score group (p = 0.036). Acute outcomes were similar in the 3 groups, including device and procedural success rates (respectively p = 0.717 and p = 1). One-month follow-up showed similar rates of death, myocardial infarction, stroke, and bleeding, as well as of a composite safety endpoint (all p > 0.05). However, vascular complications were significantly more common in the highest TAVI-CT score group (p = 0.041). The TAVI-CT score is a simple scoring system that could be routinely applied to CT imaging for TAVI planning, if the present hypothesis-generating findings are confirmed in larger prospective studies.

Strategies for Facilitating Totally Percutaneous Transfemoral TAVR Procedures

Transcatheter aortic valve replacement (TAVR) has transformed the treatment of aortic stenosis and should ideally be performed as a totally percutaneous procedure via the transfemoral (TF) approach. Peripheral vascular disease may impede valve delivery, and vascular access site complications are associated with adverse clinical outcome and increased mortality. We review strategies aimed to facilitate TF valve delivery in patients with hostile vascular anatomy and achieve percutaneous management of vascular complications.

Commissural alignment with new-generation self-expanding transcatheter heart valves during aortic replacement

Preserving coronary artery access is a crucial goal during transcatheter aortic valve replacement (TAVR) procedures, especially in case of self-expandable transcatheter heart valve (SE-THV) implantation. In this light, a proper commissural alignment is needed to avoid the risk of coronary obstruction and to permit easy vessels re-cannulation for diagnostic and interventional purposes. New-generation SE-THVs have been furnished of different markers, able to guide operators to perform a correct commissural alignment. In this case series, we describe key procedural aspects of commissural alignment for the different available SE-THVs, providing a step-by-step tutorial for each device. Lastly, we illustrate a commissural alignment in a contrast-zero TAVR.

Assessing the Best Prognostic Score for Transcatheter Aortic Valve Implantation (from the RISPEVA Registry)

The ACC/TVT score is a specific predictive model of in-hospital mortality for patients undergoing transcatheter aortic valve implantation (TAVI). The aim of this study was to test its predictive accuracy in comparison with standard surgical risk models (Logistic Euroscore, Euroscore II, and STS-PROM) in the population of TAVI patients included in the multicenter RISPEVA (Registro Italiano GISE sull'impianto di Valvola Aortica Percutanea) registry. The study cohort included 3293 patients who underwent TAVI between 2008 and 2019. The 4 risk scores were calculated for all patients. For all scores, the capability to predict 30-day mortality was assessed by means of several analyses testing calibration and discrimination. The ACC/TVT score showed moderate discrimination, with a C-statistics for 30-day mortality of 0.63, not significantly different from the standard surgical risk models. The ACC/TVT score demonstrated, in contrast, better calibration compared with the other scores, as proved by a greater correspondence between estimated probabilities and the actual observations. However, when the ACC/TVT score was tested in the subgroup of patients treated in a more contemporary period (from 2016 on), it revealed a slight tendency to lose discrimination and to overestimate mortality risk. In conclusion, in comparison with the standard surgical risk models, the ACC/TVT score demonstrated better prediction accuracy for estimation of 30-day mortality in terms of calibration. Nevertheless, its predictive reliability remained suboptimal and tended to worsen in patients treated more recently.

Thrombocytopenia Complicating Transcatheter Aortic Valve Implantation: Differences Between Two New-Generation Devices

Thrombocytopenia after TAVI is common and clinically detrimental. Retrospectively, we observed Portico recipients had a more profound platelet drop than Evolut recipients. We thus investigated periprocedural platelet damage and/orpro-inflammatory state in 64 TAVI recipients at baseline and after implantation. Platelet damage was assessed by annexin V staining and monocyte-phagocytic phenotype was assessed according to CD14/CD36 expression. Serum cytokines were measured in 20 patients. The formaldehyde-based storage solution altered platelets. When, before being loaded onto the delivery system, Portico underwent one additional flushing to those recommended, the receiving patients showed thrombocytopenia, platelet damage, and CD36-monocyte count were mitigated. A general increase in IL-6 was recorded in overall TAVI recipients, but a high serum level of IL-8, a potent thrombocytopenia inducer, was measured in Portico recipients only, including those with extra-rinsed valve. Our study suggests a platelet-injury effect by storage-solution and generates the hypothesis of a role for the biomaterial in stimulating innate-immunity. Larger prospective studies are needed.

Baseline, procedural and outcome features of patients undergoing transcatheter aortic valve implantation according to different body mass index categories

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has become first-line treatment for severe aortic valve stenosis in patients with moderate, high or prohibitive surgical risk. However, access site complications may occur more frequently in extreme body mass index (BMI) categories. The aim of this study was to describe the features and outcomes of patients undergoing TAVI in a comprehensive Italian prospective clinical registry, focusing on BMI classes.

METHODS

A national prospective database was queried for baseline, procedural, and outcome details of patients undergoing TAVI according to established BMI categories: underweight (BMI <18.5 kg/m²), normal weight (BMI 18.5-24.9 kg/m²), overweight (BMI 25.0-29.9 kg/m²), and obese (BMI≥30 kg/m²). Short- and long-term outcomes, including major adverse events (MAE), i.e. the composite of death, stroke, myocardial infarction, major vascular complication, major bleeding, or renal failure, were appraised with bivariate and multivariable analyses.

RESULTS

A total of 3075 subjects were included, 64 (2.1%) were underweight, 1319 (42.9%) were normal weight, 1152 (37.4%) were overweight, and 540 (17.6%) were obese. Several baseline differences were evident, including gender, diabetes mellitus, renal function, chronic obstructive pulmonary disease, surgical scores, and left ventricular ejection fraction (LVEF) (all P<0.05). Several procedural differences were also evident, including percutaneous approach, predilation, prosthesis type and size (all P<0.05), with postprocedural aortic regurgitation >2+ significantly more common in underweight patients (P<0.05). Nonetheless, unadjusted analysis for one-month outcomes showed similar rates for fatal and non-fatal outcomes, including MAE (all P>0.05), with the notable exception of permanent pacemaker implantation, which was more common in higher BMI classes (P=0.010) Unadjusted analysis for long-term events showed an increased rate of death in underweight patients (P=0.024). Multivariable adjusted analysis confirmed the increased risk of permanent pacemaker implantation in obese patients (P=0.015 when comparing obese vs. normal weight subjects), but disproved differences in long-term mortality and other outcomes (P>0.05 for all comparisons).

CONCLUSIONS

Irrespective of BMI class, TAVI is associated with favorable outcomes in surgical high-risk risk patients, with the notable exclusion of permanent pacemaker implantation, which is significantly more common in obese subjects.