Multiscale Finite Element Modeling of Left Ventricular Growth in Simulations of Valve Disease.

Multiscale models of the cardiovascular system are emerging as effective tools for investigating the mechanisms that drive ventricular growth and remodeling. These models can predict how molecular-level mechanisms impact organ-level structure and function and could provide new insights that help improve patient care. MyoFE is a multiscale computer framework that bridges molecular and organ-level mechanisms in a finite element model of the left ventricle that is coupled with the systemic circulation. In this study, we extend MyoFE to include a growth algorithm, based on volumetric growth theory, to simulate concentric growth (wall thickening/thinning) and eccentric growth (chamber dilation/constriction) in response to valvular diseases. Specifically in our model, concentric growth is controlled by time-averaged total stress along the fiber direction over a cardiac cycle while eccentric growth responds to time-averaged intracellular myofiber passive stress over a cardiac cycle. The new framework correctly predicted different forms of growth in response to two types of valvular diseases, namely aortic stenosis and mitral regurgitation. Furthermore, the model predicted that LV size and function are nearly restored (reversal of growth) when the disease-mimicking perturbation was removed in the simulations for each valvular disorder. In conclusion, the simulations suggest that time-averaged total stress along the fiber direction and time-averaged intracellular myofiber passive stress can be used to drive concentric and eccentric growth in simulations of valve disease.

Biventricular finite element modeling of the fetal heart in health and during critical aortic stenosis.

Finite Element simulations are a robust way of investigating cardiac biomechanics. To date, it has only been performed with the left ventricle (LV) alone for fetal hearts, even though results are likely different with biventricular (BiV) simulations. In this research, we conduct BiV simulations of the fetal heart based on 4D echocardiography images to show that it can capture the biomechanics of the normal healthy fetal heart, as well as those of fetal aortic stenosis better than the LV alone simulations. We found that performing LV alone simulations resulted in overestimation of LV stresses and pressures, compared to BiV simulations. Interestingly, inserting a compliance between the LV and right ventricle (RV) in the lumped parameter model of the LV only simulation effectively resolved these overestimations, demonstrating that the septum could be considered to play a LV-RV pressure communication role. However, stresses and strains spatial patterns remained altered from BiV simulations after the addition of the compliance. The BiV simulations corroborated previous studies in showing disease effects on the LV, where fetal aortic stenosis (AS) drastically elevated LV pressures and reduced strains and stroke volumes, which were moderated down with the addition of mitral regurgitation (MR). However, BiV simulations enabled an evaluation of the RV as well, where we observed that effects of the AS and MR on pressures and stroke volumes were generally much smaller and less consistent. The BiV simulations also enabled investigations of septal dynamics, which showed a rightward shift with AS, and partial restoration with MR. Interestingly, AS tended to enhance RV stroke volume, but MR moderated that down.

Paradoxical prognostic impact of severe aortic stenosis following trans-catheter aortic valve implantation.

BACKGROUND: Aortic valve replacement is recommended for patients with "very severe" aortic stenosis (AS), irrespective of symptomatic manifestation. Nonetheless, the prognostic ramifications of "very severe" AS, as opposed to "severe" AS, subsequent to trans-catheter aortic valve implantation (TAVI) remain enigmatic. METHODS: We enrolled consecutive patients who received TAVI at our institute between May 2015 and April 2021. We scrutinized the impact of baseline "very severe" AS upon 3-year all-cause death or heart failure hospitalization following TAVI, in comparison to "severe" AS. RESULTS: A total of 239 patients (84.8 ±â€¯5.4 years old, 58 men) were included. Baseline "very severe" AS was observed in 65 (27 %) patients, who exhibited more advanced hypertrophy and higher B-type natriuretic peptide levels compared to those with "severe" AS (p < 0.05 for both). Baseline "very severe" AS was paradoxically associated with higher freedom from the primary endpoint following TAVI compared to those with "severe" AS (p = 0.01). CONCLUSIONS: The presence of baseline "very severe" AS was paradoxically associated with improved clinical outcomes subsequent to TAVI, in contrast to the cases of "severe" AS.

Prognostic impact of insomnia in patients receiving trans-catheter aortic valve replacement.

BACKGROUND: The presence of insomnia exhibits a profound association with diverse cardiovascular pathologies. However, its prognostic implications in patients undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis remain ambiguous. METHODS: This retrospective study enrolled patients who underwent TAVR for severe aortic stenosis at a prominent academic center from 2015 to 2022. The impact of insomnia, operationally defined as the prescription of soporific agents, on the two-year composite primary outcome comprising all-cause mortality and hospital readmissions was scrutinized. RESULTS: A cohort of 345 patients (median age 85 years, 99 males) was encompassed in the analysis. All subjects underwent successful TAVR and subsequent discharge. The presence of insomnia (N = 91) emerged as an independent predictor of the two-year composite endpoint, with an adjusted hazard ratio of 1.66 (95 % confidence interval 1.08-2.57, p = 0.022), significantly delineating the two-year cumulative incidence of the primary endpoint (40 % versus 30 %, p = 0.035). CONCLUSION: Approximately one-fourth of TAVR candidates manifested symptoms of insomnia, a condition autonomously correlated with heightened mortality and morbidity following the TAVR procedure. The optimal strategy for addressing insomnia in TAVR candidates constitutes a paramount consideration for future interventions.

Fetal aortic valvuloplasty for critical aortic stenosis: single-center retrospective study focusing on postnatal outcome.

OBJECTIVE: We aimed to report our experience on fetal aortic valvuloplasty (FAV) for critical aortic stenosis (AS) focusing on the postnatal evolution of the patients. METHODS: This retrospective study was approved by our local Institutional Review Board (n°2002-0128143827). All fetuses with critical AS who underwent FAV in a single center between 01/2011 and 06/2022 were included. FAV were performed under ultrasound guidance. Technical success was based upon balloon inflation across the aortic valve and improvement of the anterograde aortic flow across the aortic valve. At birth, biventricular circulation (BVC) strategy was decided assuming the left ventricle (LV) systolic and diastolic functions would ensure the systemic circulation. RESULTS: Sixty-three FAV were performed on 58 fetuses at 24.6[21.4-32.4] weeks of gestation. The procedure was successful in 52/58(89.6%) fetuses. There were 11/58(19%) in utero demises and 9/58(15.5%) terminations of pregnancy. There were no liveborn patients after the unsuccessful procedures. 38/58(65.5%) infants were delivered at a median gestational age of 38.1[29-40.6] weeks and 21/38(55.3%) of them required prostaglandin. 28/38(73.7%) [28/58(48.3%)] children entered the BVC path at birth. Among them, 20 required an aortic valvuloplasty at birth (11 percutaneous, 9 surgical) and 8 did not require any treatment at birth but of those, 5/8 underwent a surgical valvuloplasty between day 26 and day 1200 of life. 11/28(39.3%) infants with BVC at birth required a second intervention and four of them required a third intervention. Two infants who entered the BVC at birth underwent a conversion to UVC. None of the surviving children with BVC developed pulmonary hypertension. The global survival rate in case of BVC was 22/28(78.6%) at 23.3[8-112] months of life. 10 patients had UVC at birth. Among them, 6 received comfort care from birth and only 4 underwent surgery. 3/10 patients were still alive at the latest assessment (48[22-102] months). CONCLUSION: FAV for critical aortic stenosis led to anterograde aortic flow in 89.6% of the fetuses, with BVC being achieved in 48.3% (73.7% of the live born). Among patients with BVC at birth, the rate of reintervention is high but long-term survival is satisfactory. This article is protected by copyright. All rights reserved.

Contemporary outcomes of surgical aortic valve replacement in patients referred for a transcatheter approach.

OBJECTIVES: The purpose of this study is to examine which patients referred to our structural valve clinic for potential transcatheter aortic valve replacement (TAVR) are receiving surgical aortic valve replacement (SAVR) whether due to unsuitable anatomy for TAVR versus other reasons. METHODS: Individuals referred for TAVR from January 2019 to March 2022, who ultimately underwent SAVR were examined, retrospectively. Patients were divided into 2 surgical groups: TAVR was technically unsuitable (SAVR-TU) and those in which TAVR was technically feasible (SAVR-TF). RESULTS: 215 patients referred for TAVR underwent SAVR with 61 (28.4%) patients in the SAVR-TU group and 154 (71.6%) in the SAVR-TF group. The SAVR-TU group were more commonly female (52.5% vs 23.4%, p < 0.0001), had a higher incidence of stroke at baseline (9.8% vs 2.0%, p = 0.017) were frailer (5-m gait 5.2 s vs 4.7 s, p = 0.0035), and had a higher Society of Thoracic Surgery risk score (2.2 vs 1.7, p = 0.04). In the SAVR-TU group, unsuitability for TAVR was due to inadequate aortic root anatomy (86.9%), and poor peripheral access (6.6%). In the SAVR-TF group, the most common reasons for SAVR referral were concomitant coronary artery disease (42.9%), bicuspid aortic valve disease (16.9%), and concomitant aortic aneurysm (10.4%). Overall, in-hospital mortality was 1.4% with no difference between both groups. One-year survival was 96.7%. CONCLUSION: Despite a higher trend of aortic stenosis being treated with TAVR, higher risk patients unsuitable for TAVR can have SAVR with excellent outcomes. Moreover, patients with AS and concomitant other pathology should be evaluated for cardiac surgery.

Multidisciplinary approach to long-standing left bundle branch block with dyssynchrony and aortic stenosis: case report.

Background: Cardiac resynchronization therapy (CRT) is recommended for patients with symptomatic heart failure in sinus rhythm with left ventricular ejection fraction (LVEF) ≤ 35%, QRS duration ≥ 150 ms, and left bundle branch block (LBBB) morphology. However, when severe left ventricular dysfunction and cardiogenic shock are present, treatment paradigms are often limited to palliative medical therapy or advanced therapies with durable left ventricular assist device or heart transplant as the functional and survival benefit of CRT in these patients remains uncertain. Case summary: A 77-year-old white man with long-standing LBBB with dyssynchrony, severely reduced LVEF of 4%, and severe bicuspid aortic stenosis (AS) presented with worsening heart failure symptoms. After multidisciplinary heart team evaluation and pre-operative optimization, the patient underwent a surgical aortic valve replacement with simultaneous intraoperative initiation of CRT with pacemaker (CRT-P) and temporary mechanical circulatory support. Echocardiography at 44 days and 201 days post-discharge showed an LVEF of 29% and 40%, respectively. Discussion: This case demonstrates that reverse remodelling and native heart recovery were successfully achieved in a patient with advanced structural heart disease, presenting with cardiogenic shock, through an early and aggressive approach involving multidisciplinary heart team evaluation, treatment of severe AS with surgical aortic valve replacement, prophylactic intraoperative initiation of temporary mechanical circulatory support, and early initiation of CRT-P.

Current awareness and use of transthoracic echocardiography in evaluation of valvular heart disease in Kumamoto Prefecture -a report from the Kumamoto cardiovascular echocardiography standardization project.

BACKGROUND: There are few reports on transthoracic echocardiography (TTE) for the evaluation of valvular heart disease in a specific area or region. METHODS AND RESULTS: This cross-sectional questionnaire-based survey was conducted in 2023 in Kumamoto Prefecture, where 106 hospitals provide cardiology services. Ninety-three (88%) of the hospitals completed questionnaires regarding TTE. The severity of low flow/low gradient AS was evaluated by dobutamine stress echocardiography in only 7% of hospitals and exercise stress echocardiography for asymptomatic mitral regurgitation in only 5%. Multivariate logistic regression analysis revealed that participation in remote multi-institutional echocardiographic meetings and use of the Kumamoto Prefecture echocardiographic manual were significantly associated with the use of a multi-window approach (P < 0.05). CONCLUSIONS: In Kumamoto Prefecture, echocardiographic measurements are performed according to the recommendations at a relatively low rate. Dissemination of recommendations through remote meetings and the use of the echocardiographic manual may increase the likelihood of TTE being performed according to the recommendations.

Non-invasive assessment of left ventricular filling pressure in aortic stenosis.

BACKGROUND: The assessment of left ventricular (LV) filling pressure (FP) is important for the management of aortic stenosis (AS) patients. Although, it is often restricted for predict LV FP in AS because of mitral annular calcification and a certain left ventricular hypertrophy. Thus, we tested the predictive ability of the algorithm for elevated LV FP in AS patients and also applied a recently-proposed echocardiographic scoring system of LV FP, visually assessed time difference between the mitral valve and tricuspid valve opening (VMT) score. METHODS: We enrolled consecutive 116 patients with at least moderate AS in sinus rhythm who underwent right heart catheterization and echocardiography within 7 days. Mean pulmonary artery wedge pressure (PAWP) was measured as invasive parameter of LV FP. LV diastolic dysfunction (DD) was graded according to the ASE/EACVI guidelines. The VMT score was defined as follows: time sequence of opening of mitral and tricuspid valves was scored to 0-2 (0: tricuspid valve first, 1: simultaneous, 2: mitral valve first). When the inferior vena cava was dilated, one point was added and VMT score was finally calculated as 0-3. RESULTS: Of the 116 patients, 29 patients showed elevated PAWP. Ninety patients (93%) and 67 patients (63%) showed increased values for left atrium volume index (LAVI) and E/e', respectively when the cut-off values recommended by the guidelines were applied and thus the algorism predicted elevated PAWP with a low specificity and positive predictive value (PPV). VMT ≥ 2 predicted elevated PAWP with a sensitivity of 59%, specificity of 90%, PPV of 59%, and negative predictive value of 89%. An alternative algorithm that applied tricuspid regurgitation velocity and VMT scores was tested, and its predictive ability was markedly improved. CONCLUSION: VMT score was applicable for AS patients. Alternative use of VMT score improved diagnostic accuracy of guideline-recommended algorism.

The role of external iliac artery diameter indexed to BSA score in predicting vascular access complications after transfemoral transcatheter aortic valve implantation.

Introduction: Aortic stenosis is the most common primary valve disease and requires invasive treatment. Transcatheter aortic valve implantation (TAVI) from a transfemoral access is a routine intervention worldwide. Aim: To investigate the correlation between external iliac artery diameter (EIAD) indexed to body surface area (BSA) (EIAD-BSA) and access site complications in patients undergoing TAVI via transfemoral access (TF) (TF-TAVI). Material and methods: Patients underwent TF-TAVI in 2017-2019 at the Upper-Silesian Medical Center in Katowice. Based on the preoperative multi-slice computed tomography (MSCT), pre-specified measurements of the ilio-femoral vessels were performed. The results were indexed to BSA and body mass index (BMI). Complications after TAVI were defined by Valve Academic Research Consortium 3 (VARC-3). The primary outcome regarding the adverse events after TAVI was the composite of access site complications requiring surgical intervention or blood transfusion. Results: The registry included 193 unselected patients with severe symptomatic aortic stenosis. Vascular and access-related complications including bleeding occurred in 17.1% of patients. Major TAVI access site complications (VARC-3) were reported in 5.7% of patients, while minor complications (VARC-3) occurred in 2.6%. EIAD-BSA demonstrated a positive correlation with the access site complications primary endpoint. Patients with greater EIAD-BSA had a numerically higher number of access site adverse events requiring surgical intervention or blood transfusion: n = 12 (5%) vs. n = 4 (4%), p = 0.011. Conclusions: External iliac artery diameter indexed to BSA could be an underestimated indicator of unfavorable outcomes after TF-TAVI, predicting periprocedural access site complications.

Upper extremity versus lower extremity for secondary access during transcatheter aortic valve implantation: rationale and design of the randomised TAVI XS trial.

BACKGROUND: During transcatheter aortic valve implantation (TAVI), secondary access is required for angiographic guidance and temporary pacing. The most commonly used secondary access sites are the femoral artery (angiographic guidance) and the femoral vein (temporary pacing). An upper extremity approach using the radial artery and an upper arm vein instead of the lower extremity approach using the femoral artery and femoral vein may reduce clinically relevant secondary access site-related bleeding complications, but robust evidence is lacking. TRIAL DESIGN: The TAVI XS trial is a multicentre, randomised, open-label clinical trial with blinded evaluation of endpoints. A total of 238 patients undergoing transfemoral TAVI will be included. The primary endpoint is the incidence of clinically relevant bleeding (i.e. Bleeding Academic Research Consortium (BARC) type 2, 3 or 5 bleeding) of the randomised secondary access site (either diagnostic or pacemaker access, or both) within 30 days after TAVI. Secondary endpoints include time to mobilisation after TAVI, duration of hospitalisation, any BARC type 2, 3 or 5 bleeding, and early safety at 30 days according to Valve Academic Research Consortium­3 criteria. CONCLUSION: The TAVI XS trial is the first randomised trial comparing an upper extremity approach to a lower extremity approach with regard to clinically relevant secondary access site-related bleeding complications. The results of this trial will provide important insights into the safety and efficacy of an upper extremity approach in patients undergoing transfemoral TAVI.

Acute Heart Valve Emergencies.

Within the cardiac intensive care unit, prompt recognition of severe acute valvular lesions is essential because hemodynamic collapse can occur rapidly, especially when cardiac chambers have not had time for compensatory remodeling. Within this context, optimal medical management, considerations for temporary mechanical circulatory support and decisive treatments strategies are addressed. Fundamental concepts include an appreciation for how sudden changes in flow and pressure gradients between cardiac chambers can impact hemodynamic and echocardiographic findings differently compared to similarly severe chronic lesions, as well as understanding the main causes for decompensated heart failure and cardiogenic shock for each valvular abnormality.

Aortic Stenosis and Renal Function: A Bidirectional Mendelian Randomization Analysis.

BACKGROUND: Large observational studies have demonstrated a clear inverse association between renal function and risk of aortic stenosis (AS). Whether this represents a causal, reverse causal or correlative relationship remains unclear. We investigated this using a bidirectional 2-sample Mendelian randomization approach. METHODS AND RESULTS: We collected summary statistics for the primary analysis of chronic kidney disease (CKD) and AS from genome-wide association study meta-analyses including 480 698 and 653 867 participants, respectively. We collected further genome-wide association study summary statistics from up to 1 004 040 participants for sensitivity analyses involving estimated glomerular filtration rate (eGFR) derived from creatinine, eGFR derived from cystatin C, and serum urea nitrogen. Inverse-variance weighted was the primary analysis method, with weighted-median, weighted-mode, Mendelian randomization-Egger, and Mendelian randomization-Pleiotropy Residual Sum and Outlier as sensitivity analyses. We did not find evidence of a causal relationship between genetically predicted CKD liability as the exposure and AS as the outcome (odds ratio [OR], 0.94 per unit increase in log odds of genetic liability to CKD [95% CI, 0.85-1.04], P=0.26) nor robust evidence of AS liability as the exposure and CKD as the outcome (OR, 1.04 per unit increase in log odds of genetic liability to AS [95% CI, 0.97-1.12], P=0.30). The sensitivity analyses were neutral overall, as were the analyses using eGFR derived from creatinine, eGFR derived from cystatin C, and serum urea nitrogen. All positive controls demonstrated strong significant associations. CONCLUSIONS: The present study did not find evidence of a substantial effect of genetically predicted renal impairment on risk of AS. This has important implications for research efforts that attempt to identify prevention and treatment targets for both CKD and AS.

Addressing comprehensive complexities a striking familial hypercholesterolemia case study.

BACKGROUND: Premature aortic involvement and comprehensive management strategies in familial hypercholesterolemia familial hypercholesterolemia (FH), a rare autosomal dominant genetic disorder, poses significant challenges due to its propensity for elevated low-density lipoprotein cholesterol, premature coronary heart disease, and vascular atherosclerosis. CASE PRESENTATION: Unraveling Cardiovascular Complexities: A Striking Familial Hypercholesterolemia. This case study delves into a remarkable instance of FH in a 16-year-old female who presented with chest pain and worsening dyspnea. Diagnostic evaluation revealed distinct electrocardiographic changes, elevated troponin levels, and profound dyslipidemia. Remarkable findings on transthoracic echocardiography, computed tomography angiography, and catheterization prompted multidisciplinary interventions and demonstrated remarkable enhancements in ventricular function, mitral regurgitation, and aortic stenosis. CONCLUSION: The case study underscores the urgency of comprehensive management strategies in confronting the myriad challenges of FH, emphasizing the value of early intervention, innovative therapies, and rigorous imaging modalities for unraveling the intricate cardiovascular manifestations of this condition.

Lipoprotein(a): Emerging insights and therapeutics.

The strong association between lipoprotein (a) [Lp(a)] and atherosclerotic cardiovascular disease has led to considerations of Lp(a) being a potential target for mitigating residual cardiovascular risk. While approximately 20 % of the population has an Lp(a) level greater than 50 mg/dL, there are no currently available pharmacological lipid-lowering therapies that have demonstrated substantial reduction in Lp(a). Novel therapies to lower Lp(a) include antisense oligonucleotides and small-interfering ribonucleic acid molecules and have shown promising results in phase 2 trials. Phase 3 trials are currently underway and will test the causal relationship between Lp(a) and ASCVD and whether lowering Lp(a) reduces cardiovascular outcomes. In this review, we summarize emerging insights related to Lp(a)'s role as a risk-enhancing factor for ASCVD, association with calcific aortic stenosis, effects of existing therapies on Lp(a) levels, and variations amongst patient populations. The evolving therapeutic landscape of emerging therapeutics is further discussed.

Examining Lack of Referrals to Heart Valve Specialists as Mechanisms of Potential Underutilization of Aortic Valve Replacement.

BACKGROUND: Recent studies suggest that Aortic Valve Replacement (AVR) remains underutilized. AIMS: Investigate the potential role of non-referral to Heart Valve Specialists (HVS) on AVR utilization. METHODS: Patients with severe aortic stenosis (AS) between 2015 and 2018, who met class I indication for intervention, were identified. Baseline data and process-related parameters were collected to analyze referral predictors and evaluate outcomes. RESULTS: Among 981 patients meeting criteria AVR, 790 patients (80.5%) were assessed by HVS within six months of index TTE. Factors linked to reduced referral included increasing age (OR: 0.95; 95% CI: 0.94 - 0.97; P <0.001), unmarried status (OR: 0.59; 95% CI: 0.43 - 0.83; P =0.002) and inpatient TTE (OR: 0.27; 95% CI: 0.19 - 0.38; P <0.001). Conversely, higher hematocrit (OR: 1.13; 95% CI: 1.09 - 1.16; P <0.001) and eGFR (OR: 1.01; 95% CI: 1.00 - 1.02; P =0.003), mean aortic valve gradient (OR: 1.03; 95% CI: 1.01 - 1.04; P <0.001) and preserved LVEF (OR: 1.59; 95% CI: 1.02 - 2.48; P =0.04), were associated with increased referral likelihood. Moreover, patients assessed by HVS referral as a time-dependent covariate had a significantly lower two-year mortality risk than those who were not (aHR: 0.30; 95% CI: 0.23- 0.39; P < 0.001). CONCLUSION: A substantial proportion of severe AS patients meeting indications for AVR are not evaluated by HVS and experience markedly increased mortality. Further research is warranted to assess the efficacy of care delivery mechanisms, such as e-consults, and telemedicine, to improve access to HVS expertise.