Clinical Significance of Diffusion-Weighted Brain MRI Lesions After TAVR: Results of a Patient-Level Pooled Analysis.

BACKGROUND: Acute brain infarction detected by diffusion-weighted magnetic resonance imaging (DW-MRI) is common after transcatheter aortic valve replacement (TAVR), but its clinical relevance is uncertain. OBJECTIVES: The authors investigated the relationship between DW-MRI total lesion number (TLN), individual lesion volume (ILV), and total lesion volume (TLV) and clinical stroke outcomes after TAVR. METHODS: Patient-level data were pooled from 4 prospective TAVR embolic protection studies, with consistent predischarge DW-MRI acquisition and core laboratory analysis. C-statistic was used to determine the best DW-MRI measure associated with clinical stroke. RESULTS: A total of 495 of 603 patients undergoing TAVR completed the predischarge DW-MRI. At 30 days, the rate of clinical ischemic stroke was 6.9%. Acute ischemic brain injury was seen in 85% of patients with 5.5 ± 7.3 discrete lesions per patient, mean ILV of 78.2 ± 257.1 mm3, and mean TLV of 555 ± 1,039 mm3. The C-statistic was 0.84 for TLV, 0.81 for number of lesions, and 0.82 for maximum ILV in predicting ischemic stroke. On the basis of the TLV cutpoint as defined by receiver operating characteristic (ROC), patients with a TLV >500 mm3 (vs TLV ≤500 mm3) had more ischemic stroke (18.2% vs 2.3%; P < 0.0001), more disabling strokes (8.8% vs 0.9%; P < 0.0001), and less complete stroke recovery (44% vs 62.5%; P = 0.001) at 30 days. CONCLUSIONS: Our study confirms that the number, size, and total volume of acute brain infarction defined by DW-MRI are each associated with clinical ischemic strokes, disabling strokes, and worse stroke recovery in patients undergoing TAVR and may have value as surrogate outcomes in stroke prevention trials. (A Prospective, Randomized Evaluation of the TriGuard™ HDH Embolic Deflection Device During TAVI [DEFLECT III]; NCT02070731) (A Study to Evaluate the Neuro-embolic Consequences of TAVR [NeuroTAVR]; NCT02073864) (The REFLECT Trial: Cerebral Protection to Reduce Cerebral Embolic Lesions After Transcatheter Aortic Valve Implantation [REFLECT I]; NCT02536196) (The REFLECT Trial: Cerebral Protection to Reduce Cerebral Embolic Lesions After Transcatheter Aortic Valve Implantation [REFLECT II]; NCT02536196).

Incidence, Predictors, and Prognostic Impact of Neurologic Events After TAVR According to VARC-3 Criteria.

BACKGROUND: The Valve Academic Research Consortium (VARC)-3 definition for neurologic events after transcatheter aortic valve replacement (TAVR) lacks clinical validation. OBJECTIVES: This study sought to determine the incidence, predictors, and clinical impact of neurologic events following TAVR as defined by VARC-3 criteria. METHODS: This was a multicenter study including 2,924 patients with severe aortic stenosis undergoing TAVR. Based on Neurologic Academic Research Consortium (NeuroARC) classification, neurologic events were classified as NeuroARC type 1 (stroke), NeuroARC type 2 (covert central nervous system injury), and NeuroARC type 3 (transient ischemic attack and delirium). Baseline, procedural, and follow-up data were prospectively collected in a dedicated database. RESULTS: After a median follow-up of 13 (7-37) months, neurologic events occurred in 471 patients (16.1%), NeuroARC type 1, 2, and 3 in 37.4%, 4.7%, and 58.0% of cases, respectively, and the majority (58.6%) were periprocedural. Advanced age, chronic kidney disease, atrial fibrillation, major vascular complications, and in-hospital bleeding determined an increased risk of periprocedural events (P < 0.03 for all). Neurologic events occurring during the periprocedural time frame were independently associated with a substantial increase in mortality at 1 year after the intervention (HR: 1.91; 95% CI: 1.23-2.97; P = 0.004). However, although NeuroARC type 1 was associated with an increased mortality risk (IRR: 3.38; 95% CI: 2.30-5.56; P < 0.001 and IRR: 21.7; 95% CI: 9.63-49.1; P < 0.001 for ischemic and hemorrhagic stroke, respectively), the occurrence of NeuroARC type 3 events had no impact on mortality. CONCLUSIONS: Neurologic events after TAVR were associated with poorer short- and long-term survival. This correlation was related to the type of NeuroARC event defined by the VARC-3 criteria. Given the negative impact on clinical outcomes, every attempt should be made to reduce the risk of neurologic complications after TAVR.

Impact of cerebral protection on observed versus predicted in-hospital stroke in a high stroke risk TAVR cohort.

BACKGROUND: Despite impressive improvements in the safety profile of Transcatheter aortic valve replacement (TAVR), the risk for peri-procedural stroke after TAVR has not declined substantially. In an effort to reduce periprocedural stroke, cerebral embolic protection (CEP) devices have been utilized but have yet to demonstrate benefit in all-comers. There is a paucity of data supporting the utilization of CEP in TAVR patients with an anticipated high risk for peri-procedural stroke. METHODS: The Transcatheter Aortic Valve Replacement In-Hospital Stroke (TASK) score is a clinical risk tool for predicting the in-hospital stroke risk of patients undergoing transfemoral TAVR. This score was used to identify high-risk patients and calculate the expected in-hospital stroke risk. This was a single-centre cohort study in all consecutive TAVR patients who had placement of CEP. The observed versus expected ratio for peri-procedural stroke was calculated. To obtain 95% credible intervals, we used 1000 bootstrapped samples of the original cohort sample size without replacement and recalculated the TASK predicted scores. RESULTS: The study included 103 patients. The median age was 83 (IQR 78,89). 63 were male (61.1%) and 45 (43.69%) had a history of previous Stroke or TIA. Two patients had an in-hospital stroke after TAVR (1.94%). The expected risk of in-hospital stroke based on the TASK score was 3.39% (95% CI 3.07-3.73). The observed versus expected ratio was 0.57 (95% CI 0.52-0.64). CONCLUSION: In this single-center study, we found that in patients undergoing TAVR with high stroke risk, CEP reduced the in-hospital stroke risk by 43% when compared with the risk-score predicted rate. CLINICAL TRIAL NUMBER: N/A.

Quantification of Aortic Valve Fibrotic and Calcific Tissue from CTA: Prospective Comparison with Histology.

Background Quantifying the fibrotic and calcific composition of the aortic valve at CT angiography (CTA) can be useful for assessing disease severity and outcomes of patients with aortic stenosis (AS); however, it has not yet been validated against quantitative histologic findings. Purpose To compare quantification of aortic valve fibrotic and calcific tissue composition at CTA versus histologic examination. Materials and Methods This prospective study included patients who underwent CTA before either surgical aortic valve replacement for AS or orthotopic heart transplant (controls) at two centers between January 2022 and April 2023. At CTA, fibrotic and calcific tissue composition were quantified using automated Gaussian mixture modeling applied to the density of aortic valve tissue components, calculated as [(volume/total tissue volume) × 100]. For histologic evaluation, explanted valve cusps were stained with Movat pentachrome as well as hematoxylin and eosin. For each cusp, three 5-µm slices were obtained. Fibrotic and calcific tissue composition were quantified using a validated artificial intelligence tool and averaged across the aortic valve. Correlations were assessed using the Spearman rank correlation coefficient. Intermodality and interobserver variability were measured using the intraclass correlation coefficient (ICC) and Bland-Altman plots. Results Twenty-nine participants (mean age, 63 years ± 10 [SD]; 23 male) were evaluated: 19 with severe AS, five with moderate AS, and five controls. Fibrocalcific tissue composition strongly correlated with histologic findings (r = 0.92; P < .001). The agreement between CTA and histologic findings for fibrocalcific tissue quantification was excellent (ICC, 0.94; P = .001), with underestimation of fibrotic composition at CTA (bias, -4.9%; 95% limits of agreement [LoA]: -18.5%, 8.7%). Finally, there was excellent interobserver repeatability for fibrotic (ICC, 0.99) and calcific (ICC, 0.99) aortic valve tissue volume measurements, with no evidence of a difference in measurements between readers (bias, -0.04 cm3 [95% LoA: -0.27 cm3, 0.19 cm3] and 0.02 cm3 [95% LoA: -0.14 cm3, 0.19 cm3], respectively). Conclusion In a direct comparison, standardized quantitative aortic valve tissue characterization at CTA showed excellent concordance with histologic findings and demonstrated interobserver reproducibility. Clinical trial registration no. NCT06136689 Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Almeida in this issue.

The importance of MDCT in the evaluation of risk factors before the TAVI procedure and its complications after implantation.

Transcatheter aortic valve implantation (TAVI) is the alternative to surgical valve replacement, expanding its indications in the latest guidelines. Multimodal CT (MDCT) is essential in patient selection and detection of complications. Vascular complications are frequent, so it is important to analyse the anatomy of the vessels before the procedure. Regarding annular ruptures and ventricular perforations, the volume and distribution of calcium and the ventricular diameter play an important role. Finally, valve migration is a rare complication that can occur both during and after TAVI. Proper planning of the MDCT procedure reduces the risk of complications and gives the interventional cardiologist security both before and during the procedure.

Comparison of Pressure vs Volume Overload Ventricular Wall Stress in Patients With Valvular Heart Disease.

BACKGROUND: Aortic stenosis (AS) and mitral regurgitation (MR) result in different patterns of left ventricular remodeling and hypertrophy. OBJECTIVES: We characterized left ventricular wall stress (LVWS) profiles in pressure and volume-overloaded systems, examined the relationship between baseline LVWS and cardiac remodeling, and assessed the acute effects of valve intervention on LVWS using invasive pressures combined with cardiac magnetic resonance (CMR) imaging measures of left ventricular volumes/mass. METHODS: A total of 47 patients with severe AS undergoing transcatheter aortic valve replacement (TAVR) and 15 patients with severe MR undergoing MitraClip (MC) underwent a 6-minute walk test (6MWT), transthoracic echocardiogram, and CMR before their procedures. Catheters in the left ventricle were used to record hemodynamic changes before and after valve/clip deployment. This was integrated with CMR data to calculate LVWS before and after intervention. RESULTS: The TAVR group demonstrated significant reductions in systolic LVWS post procedure (median 24.7 Pa [IQR: 14 Pa] pre vs median 17.3 Pa [IQR: 12 Pa] post; P < 0.001). The MC group demonstrated significant reductions in diastolic LVWS (median 6.4 Pa [IQR: 5 Pa] pre vs median 4.3 Pa [IQR: 4.1 Pa] post; P = 0.021) with no significant change in systolic LVWS (30.6 ±1.61 pre vs 33 ±2.47 Pa post; P = 0.16). There was an inverse correlation between baseline systolic LVWS and 6MWT in the TAVR group (r = -0.31; P = 0.04). CONCLUSIONS: TAVR results in significant reductions in systolic LVWS acutely. MC results in significant reductions in diastolic LVWS. Higher baseline systolic LVWS in TAVR is associated with shorter 6MWT suggesting that in AS, LVWS may be a useful marker of early decompensation.

A Guide to Transcatheter Aortic Valve Design and Systematic Planning for a Redo-TAV (TAV-in-TAV) Procedure.

Transcatheter aortic valve replacement (TAVR) has become more common than surgical aortic valve replacement since 2016, with over 200,000 procedures globally each year. As patients increasingly outlive their TAVR devices, managing these cases is a growing concern. Treatment options include surgical removal of the old TAVR device (transcatheter aortic valve [TAV] explant) or implantation of a new transcatheter aortic valve (redo TAV). Redo TAV is complex because of the unique designs of TAV devices; compatibility issues; and the need for individualized planning based on factors such as implant depth, shape, and coronary artery relationships. This review serves as a comprehensive guide for redo TAV, detailing the design characteristics of TAV devices, device compatibility, standardized terminology, and a structured approach for computed tomography analysis. It aims to facilitate decision making, risk identification, and achieving optimal outcomes in redo TAV procedures.

3-Year Outcomes From the Evolut Low Risk TAVR Bicuspid Study.

BACKGROUND: Outcomes from transcatheter aortic valve replacement (TAVR) in low-surgical risk patients with bicuspid aortic stenosis beyond 2 years are limited. OBJECTIVES: This study aimed to evaluate 3-year clinical and echocardiographic outcomes from the Evolut Low Risk Bicuspid Study. METHODS: The Evolut Low Risk Bicuspid Study is a prospective, multicenter, single-arm study conducted in 25 U.S. CENTERS: Patients with severe aortic stenosis at low surgical risk with bicuspid aortic valve anatomy (all subtypes) underwent TAVR with a self-expanding, supra-annular Evolut R or PRO (Medtronic) bioprosthesis. An independent clinical events committee adjudicated all deaths and endpoint-related adverse events, and a central echocardiographic core laboratory assessed hemodynamic endpoints. RESULTS: An attempted implant was performed in 150 patients from December 2018 to October 2019. The mean age was 70.3 ± 5.5 years, 48% (72/150) of the patients were women, and the mean Society of Thoracic Surgeons Predicted Risk of Mortality score was 1.3% (Q1-Q3: 0.9%-1.7%). Sievers type 1 was the dominant bicuspid morphology (90.7%, 136/150). The Kaplan-Meier rates of all-cause mortality or disabling stroke were 1.3% (95% CI: 0.3%-5.3%) at 1 year, 3.4% (95% CI: 1.4%-8.1%) at 2 years, and 4.1% (95% CI: 1.6%-10.7%) at 3 years. The incidence of new permanent pacemaker implantation was 19.4% (95% CI: 12.4%-29.6%) at 3 years. There were no instances of moderate or severe paravalvular aortic regurgitation at 2 and 3 years after TAVR. CONCLUSIONS: The 3-year results from the Evolut Low Risk Bicuspid Study demonstrate low rates of all-cause mortality or disabling stroke and favorable hemodynamic performance.

Association Between Aortic Wall Thrombus and Thromboembolic Events After Transfemoral Transcatheter Aortic Valve Replacement.

BACKGROUND: Thromboembolic events, particularly strokes, remain a major complication of transcatheter aortic valve replacement (TAVR). Embolic protection devices have failed to show significant clinical benefit in large randomized clinical trials. Aortic wall thrombus (AWT) is often observed on multidetector computed tomography during TAVR work-up, but its prognostic significance is uncertain. OBJECTIVES: This study sought to evaluate the association between the presence of AWT and the incidence of thromboembolic outcomes in patients undergoing transfemoral (TF) TAVR for severe aortic stenosis. METHODS: This was a prospective cohort study of consecutive patients who underwent TF TAVR for severe aortic stenosis between January 2011 and April 2022. A dedicated scale (range: 0-10) was qualitatively used to assess AWT. The primary outcome was a composite of procedural thromboembolic events defined as ischemic stroke, blue toe syndrome, bowel ischemia, or other solid organ infarction. The secondary endpoints were ischemic strokes and procedural death. RESULTS: Of the 641 patients included, severe AWT (score ≥8) was identified in 73 (11.4%). The presence of severe AWT was strongly associated with an increase in the primary outcome (OR: 8.48; 95% CI: 3.36-21.40; P < 0.001). This relationship persisted following multivariable analysis, which adjusted for comorbidities and procedural characteristics. The presence of severe AWT was also found to be associated with an increased incidence of stroke and procedural death (OR: 5.66; 95% CI: 2.00-15.30; P = 0.002 and OR: 4.66; 95% CI: 1.80-11.30; P = 0.002, respectively). CONCLUSIONS: The presence of severe AWT on preprocedural multidetector computed tomography is strongly associated with thromboembolic complications including stroke and mortality after TF TAVR.

Valve-in-Valve-in-Valve.

In the case of the degeneration of surgical aortic valve replacement (SAVR), the transcatheter aortic valve implantation (TAVI) has become the standard. However, these valves are also susceptible to deterioration. In such instances, a new TAVI implantation may be considered. We present the case of a patient with a SAVR who underwent two TAVI procedures, spaced 8 years apart. We discuss important practical aspects, including the risk of coronary obstruction and the final valve diameter.

Myocardial transcriptomic analysis of diabetic patients with aortic stenosis: key role for mitochondrial calcium signaling.

BACKGROUND: Type 2 diabetes (T2D) is a frequent comorbidity encountered in patients with severe aortic stenosis (AS), leading to an adverse left ventricular (LV) remodeling and dysfunction. Metabolic alterations have been suggested as contributors of the deleterious effect of T2D on LV remodeling and function in patients with severe AS, but so far, the underlying mechanisms remain unclear. Mitochondria play a central role in the regulation of cardiac energy metabolism. OBJECTIVES: We aimed to explore the mitochondrial alterations associated with the deleterious effect of T2D on LV remodeling and function in patients with AS, preserved ejection fraction, and no additional heart disease. METHODS: We combined an in-depth clinical, biological and echocardiography phenotype of patients with severe AS, with (n = 34) or without (n = 50) T2D, referred for a valve replacement, with transcriptomic and histological analyses of an intra-operative myocardial LV biopsy. RESULTS: T2D patients had similar AS severity but displayed worse cardiac remodeling, systolic and diastolic function than non-diabetics. RNAseq analysis identified 1029 significantly differentially expressed genes. Functional enrichment analysis revealed several T2D-specific upregulated pathways despite comorbidity adjustment, gathering regulation of inflammation, extracellular matrix organization, endothelial function/angiogenesis, and adaptation to cardiac hypertrophy. Downregulated gene sets independently associated with T2D were related to mitochondrial respiratory chain organization/function and mitochondrial organization. Generation of causal networks suggested a reduced Ca2+ signaling up to the mitochondria, with the measured gene remodeling of the mitochondrial Ca2+ uniporter in favor of enhanced uptake. Histological analyses supported a greater cardiomyocyte hypertrophy and a decreased proximity between the mitochondrial VDAC porin and the reticular IP3-receptor in T2D. CONCLUSIONS: Our data support a crucial role for mitochondrial Ca2+ signaling in T2D-induced cardiac dysfunction in severe AS patients, from a structural reticulum-mitochondria Ca2+ uncoupling to a mitochondrial gene remodeling. Thus, our findings open a new therapeutic avenue to be tested in animal models and further human cardiac biopsies in order to propose new treatments for T2D patients suffering from AS. TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; Unique Identifier: NCT01862237.