Patients with paradoxical low-flow, low-gradient aortic stenosis gain the least benefit from TAVI among all hemodynamic subtypes.

BACKGROUND: Substantial controversy exists regarding the clinical benefit of patients with severe paradoxical low-flow, low-gradient aortic stenosis (PLF-LG AS) from TAVI. Therefore, we compared post-TAVI benefit by long-term mortality (all-cause, CV and SCD), clinical improvement of heart failure symptoms, and cardiac reverse remodelling in guideline-defined AS subtypes. METHODS: We prospectively included 250 consecutive TAVI patients. TTE, 6mwt, MLHFQ, NYHA status and NT-proBNP were recorded at baseline and 6 months. Long-term mortality and causes of death were assessed. RESULTS: 107 individuals suffered from normal EF, high gradient AS (NEF-HG AS), 36 from low EF, high gradient AS (LEF-HG), 52 from "classic" low-flow, low-gradient AS (LEF-LG AS), and 38 from paradoxical low-flow, low-gradient AS (PLF-LG AS). TAVI lead to a significant decrease in MLHFQ score and NT-proBNP levels in all subtypes except for PLF-LG. Regarding reverse remodelling, a significant increase in EF and decrease in LVEDV was present only in subtypes with reduced baseline EF, whereas a significant decrease in LVMI and LAVI could be observed in all subtypes except for PLF-LG. During a follow-up of 3-5 years, PLF-LG patients exhibited the poorest survival among all subtypes (HR 4.2, P = 0.0002 for CV mortality; HR 7.3, P = 0.004 for SCD, in comparison with NEF-HG). Importantly, PLF-LG was independently predictive for CV mortality (HR 2.9 [1.3-6.9], P = 0.009). CONCLUSIONS: PLF-LG patients exhibit the highest mortality (particularly CV and SCD), the poorest symptomatic benefit and the least reverse cardiac remodelling after TAVI among all subtypes. Thus, this cohort seems to gain the least benefit.

Cardiac fibrosis as a predictor for sudden cardiac death after transcatheter aortic valve implantation.

BACKGROUND: Cardiac fibrosis plays a major pathophysiological role in any form of chronic heart disease, and high levels are associated with poor outcome. Diffuse and focal cardiac fibrosis are different subtypes, which have different pathomechanisms and prognostic implications. The total fibrosis burden in endomyocardial biopsy tissue was recently proved to play an independent prognostic role in aortic stenosis patients after transcatheter aortic valve implantation (TAVI). AIMS: Here, for the first time, we aim to assess the specific impact of different fibrosis subtypes on sudden cardiac death (SCD) as a primary reason for cardiovascular mortality after TAVI. METHODS: The fibrosis pattern was assessed histologically in the left ventricular biopsies obtained during TAVI interventions in 161 patients, who received a structured follow-up thereafter. RESULTS: Receiver operating characteristic analyses, performed 6, 12, 24 and 48 months after TAVI, showed diffuse, but not focal, fibrosis as a significant predictor for SCD at all timepoints, with the highest area under the curve at the first time point and a decrease in its SCD predictivity over time. In both multivariate Cox proportional hazards and Fine-Gray competing risk models, including both fibrosis subtypes, as well as age, sex and ejection fraction, high diffuse fibrosis remained statistically significant. Accordingly, it represents an independent SCD predictor, most importantly for the occurrence of early events. CONCLUSIONS: The burden of diffuse cardiac fibrosis plays an important and independent prognostic role regarding SCD early after TAVI. Therefore, the histological evaluation of fibrosis topography has value as a prognostic tool for TAVI patients and may help to tailor individualised approaches to optimise their postinterventional management.

CMR-based cardiac phenotyping in different forms of heart failure.

Heart failure (HF) is a heterogenous disease requiring precise diagnostics and knowledge of pathophysiological processes. Since structural and functional imaging data are scarce we hypothesized that cardiac magnetic resonance (CMR)-based analyses would provide accurate characterization and mechanistic insights into different HF groups comprising preserved (HFpEF), mid-range (HFmrEF) and reduced ejection fraction (HFrEF). 22 HFpEF, 17 HFmrEF and 15 HFrEF patients as well as 19 healthy volunteers were included. CMR image assessment contained left atrial (LA) and left ventricular (LV) volumetric evaluation as well as left atrioventricular coupling index (LACI). Furthermore, CMR feature-tracking included LV and LA strain in terms of reservoir (Es), conduit (Ee) and active boosterpump (Ea) function. CMR-based tissue characterization comprised T1 mapping as well as late-gadolinium enhancement (LGE) analyses. HFpEF patients showed predominant atrial impairment (Es 20.8%vs.25.4%, p = 0.02 and Ee 8.3%vs.13.5%, p = 0.001) and increased LACI compared to healthy controls (14.5%vs.23.3%, p = 0.004). Patients with HFmrEF showed LV enlargement but mostly preserved LA function with a compensatory increase in LA boosterpump (LA Ea: 15.0%, p = 0.049). In HFrEF LA and LV functional impairment was documented (Es: 14.2%, Ee: 5.4% p < 0.001 respectively; Ea: 8.8%, p = 0.02). This was paralleled by non-invasively assessed progressive fibrosis (T1 mapping and LGE; HFrEF > HFmrEF > HFpEF). CMR-imaging reveals insights into HF phenotypes with mainly atrial affection in HFpEF, ventricular affection with atrial compensation in HFmrEF and global impairment in HFrEF paralleled by progressive LV fibrosis. These data suggest a necessity for a personalized HF management based on imaging findings for future optimized patient management.

NaV1.8 as Proarrhythmic Target in a Ventricular Cardiac Stem Cell Model.

The sodium channel NaV1.8, encoded by the SCN10A gene, has recently emerged as a potential regulator of cardiac electrophysiology. We have previously shown that NaV1.8 contributes to arrhythmogenesis by inducing a persistent Na+ current (late Na+ current, INaL) in human atrial and ventricular cardiomyocytes (CM). We now aim to further investigate the contribution of NaV1.8 to human ventricular arrhythmogenesis at the CM-specific level using pharmacological inhibition as well as a genetic knockout (KO) of SCN10A in induced pluripotent stem cell CM (iPSC-CM). In functional voltage-clamp experiments, we demonstrate that INaL was significantly reduced in ventricular SCN10A-KO iPSC-CM and in control CM after a specific pharmacological inhibition of NaV1.8. In contrast, we did not find any effects on ventricular APD90. The frequency of spontaneous sarcoplasmic reticulum Ca2+ sparks and waves were reduced in SCN10A-KO iPSC-CM and control cells following the pharmacological inhibition of NaV1.8. We further analyzed potential triggers of arrhythmias and found reduced delayed afterdepolarizations (DAD) in SCN10A-KO iPSC-CM and after the specific inhibition of NaV1.8 in control cells. In conclusion, we show that NaV1.8-induced INaL primarily impacts arrhythmogenesis at a subcellular level, with minimal effects on systolic cellular Ca2+ release. The inhibition or knockout of NaV1.8 diminishes proarrhythmic triggers in ventricular CM. In conjunction with our previously published results, this work confirms NaV1.8 as a proarrhythmic target that may be useful in an anti-arrhythmic therapeutic strategy.

2-Year Outcomes of an Atrial Shunt Device in HFpEF/HFmrEF: Results From REDUCE LAP-HF II.

BACKGROUND: The REDUCE LAP-HF II (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure II) trial found that, compared with a sham procedure, the Corvia Atrial Shunt did not improve outcomes in heart failure with preserved or mildly reduced ejection fraction. However, after 12-month follow-up, "responders" (peak-exercise pulmonary vascular resistance <1.74 WU and absence of a cardiac rhythm management device) were identified. OBJECTIVES: This study sought to determine: 1) the overall efficacy and safety of the atrial shunt vs sham control after 2 years of follow-up; and 2) whether the benefits of atrial shunting are sustained in responders during longer-term follow-up or are offset by adverse effects of the shunt. METHODS: The study analyzed 2-year outcomes in the overall REDUCE LAP-HF II trial, as well as in responder and nonresponder subgroups. The primary endpoint was a hierarchical composite of cardiovascular death or nonfatal ischemic/embolic stroke, total heart failure events, and change in health status. RESULTS: In 621 randomized patients, there was no difference between the shunt (n = 309) and sham (n = 312) groups in the primary endpoint (win ratio: 1.01 [95% CI: 0.82-1.24]) or its individual components at 2 years. Shunt patency at 24 months was 98% in shunt-treated patients. Cardiovascular mortality and nonfatal ischemic stroke were not different between the groups; however, major adverse cardiac events were more common in those patients assigned to the shunt compared with sham (6.9% vs 2.7%; P = 0.018). More patients randomized to the shunt had an increase in right ventricular volume of ≥30% compared with the sham control (39% vs 28%, respectively; P < 0.001), but right ventricular dysfunction was uncommon and not different between the treatment groups. In responders (n = 313), the shunt was superior to sham (win ratio: 1.36 [95% CI: 1.02-1.83]; P = 0.037, with 51% fewer HF events [incidence rate ratio: 0.49 [95% CI: 0.25-0.95]; P = 0.034]). In nonresponders (n = 265), atrial shunting was inferior to sham (win ratio: 0.73 [95% CI: 0.54-0.98]). CONCLUSIONS: At 2 years of follow-up in REDUCE LAP-HF II, there was no difference in efficacy between the atrial shunt and sham groups in the overall trial group. The potential clinical benefit identified in the responder group after 1 and 2 years of follow-up is currently being evaluated in the RESPONDER-HF (Re-Evaluation of the Corvia Atrial Shunt Device in a Precision Medicine Trial to Determine Efficacy in Mildly Reduced or Preserved Ejection Fraction Heart Failure) trial. (Reduce Elevated Left Atrial Pressure in Patients With Heart Failure II [REDUCE LAP-HF II]; NCT03088033).

Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment.

The aetiology of heart failure with preserved ejection fraction (HFpEF) is heterogenous and overlaps with that of several comorbidities like atrial fibrillation, diabetes mellitus, chronic kidney disease, valvular heart disease, iron deficiency, or sarcopenia. The diagnosis of HFpEF involves evaluating cardiac dysfunction through imaging techniques and assessing increased left ventricular filling pressure, which can be measured directly or estimated through various proxies including natriuretic peptides. To better narrow down the differential diagnosis of HFpEF, European and American heart failure guidelines advocate the use of different algorithms including comorbidities that require diagnosis and rigorous treatment during the evaluation process. Therapeutic recommendations differ between guidelines. Whilst sodium glucose transporter 2 inhibitors have a solid evidence base, the recommendations differ with regard to the use of inhibitors of the renin-angiotensin-aldosterone axis. Unless indicated for specific comorbidities, the use of beta-blockers should be discouraged in HFpEF. The aim of this article is to provide an overview of the current state of the art in HFpEF diagnosis, clinical evaluation, and treatment.

Atrial Shunt Device Effects on Cardiac Structure and Function in Heart Failure With Preserved Ejection Fraction: The REDUCE LAP-HF II Randomized Clinical Trial.

Importance: Although the results of A Study to Evaluate the Corvia Medical Inc IASD System II to Reduce Elevated Left Atrial Pressure in Patients with Heart Failure (REDUCE LAP-HF II) trial were neutral overall, atrial shunt therapy demonstrated potential efficacy in responders (no latent pulmonary vascular disease and no cardiac rhythm management device). Post hoc analyses were conducted to evaluate the effect of shunt vs sham stratified by responder status. Objective: To evaluate the effect of atrial shunt vs sham control on cardiac structure/function in the overall study and stratified by responder status. Design, Setting, and Participants: This was a sham-controlled randomized clinical trial of an atrial shunt device in heart failure with preserved ejection fraction (HFpEF)/HF with mildly reduced EF (HFmrEF). Trial participants with evaluable echocardiography scans were recruited from 89 international medical centers. Data were analyzed from April 2023 to January 2024. Interventions: Atrial shunt device or sham control. Main Outcome Measures: Changes in echocardiographic measures from baseline to 1, 6, 12, and 24 months after index procedure. Results: The modified intention-to-treat analysis of the REDUCE LAP-HF II trial included 621 randomized patients (median [IQR] age, 72.0 [66.0-77.0] years; 382 female [61.5%]; shunt arm, 309 [49.8%]; sham control arm, 312 [50.2%]). Through 24 months, 212 of 217 patients (98%) in the shunt arm with evaluable echocardiograms had patent shunts. In the overall trial population, the shunt reduced left ventricular (LV) end-diastolic volume (mean difference, -5.65 mL; P <.001), left atrial (LA) minimal volume (mean difference, -2.8 mL; P =.01), and improved LV systolic tissue Doppler velocity (mean difference, 0.69 cm/s; P <.001) and LA emptying fraction (mean difference, 1.88 percentage units; P =.02) compared with sham. Shunt treatment also increased right ventricular (RV; mean difference, 9.58 mL; P <.001) and right atrial (RA; mean difference, 9.71 mL; P <.001) volumes but had no effect on RV systolic function, pulmonary artery pressure, or RA pressure compared with sham. In the shunt arm, responders had smaller increases in RV end-diastolic volume (mean difference, 5.71 mL vs 15.18 mL; interaction P =.01), RV end-systolic volume (mean difference, 1.58 mL vs 7.89 mL; interaction P =.002), and RV/LV ratio (mean difference, 0.07 vs 0.20; interaction P <.001) and larger increases in transmitral A wave velocity (mean difference, 5.08 cm/s vs -1.97 cm/s; interaction P =.02) compared with nonresponders randomized to the shunt, suggesting greater ability to accommodate shunted blood through the pulmonary circulation enabling LA unloading. Conclusions and Relevance: In this post hoc analysis of the REDUCE LAP-HF II trial, over 2 years of follow-up, atrial shunting led to reverse remodeling of left-sided chambers and increases in volume of right-sided chambers consistent with the shunt flow but no change in RV systolic function compared with sham. Changes in cardiac structure/function were more favorable in responders compared with nonresponders treated with the shunt, supporting the previously identified responder group hypothesis and mechanism, although further evaluation with longer follow-up is needed. Trial Registration: ClinicalTrials.gov Identifier: NCT03088033.

Randomized investigation of the MitraClip device in heart failure: Design and rationale of the RESHAPE-HF2 trial design.

AIMS: The safety and effectiveness of the MitraClip device to treat functional mitral regurgitation (FMR) has been tested in previous clinical trials yielding somewhat heterogeneous results in heart failure (HF) patients. Over time, the MitraClip device system has been modified and clinical practice evolved to consider also less severely diseased HF patients with FMR for this therapeutic option. The RESHAPE-HF2 trial aims to assess the safety and effectiveness of the MitraClip device system on top of medical therapy considered optimal in the treatment of clinically significant FMR in symptomatic patients with chronic HF. METHODS: The RESHAPE-HF2 is an investigator-initiated, prospective, randomized, parallel-controlled, multicentre trial designed to evaluate the use of the MitraClip device (used in the most up-to-date version as available at sites) plus optimal standard of care therapy (device group) compared to optimal standard of care therapy alone (control group). Eligible subjects have signs and symptoms of HF (New York Heart Association [NYHA] class II-IV despite optimal therapy), and have moderate-to-severe or severe FMR, as confirmed by a central echocardiography core laboratory; have an ejection fraction between ≥20% and ≤50% (initially 15-35% for NYHA class II patients, and 15-45% for NYHA class III/IV patients); have been adequately treated per applicable standards, and have received appropriate revascularization and cardiac resynchronization therapy, if eligible; had a HF hospitalization or elevated natriuretic peptides (B-type natriuretic peptide [BNP] ≥300 pg/ml or N-terminal proBNP ≥1000 pg/ml) in the last 90 days; and in whom isolated mitral valve surgery is not a recommended treatment option. The trial has three primary endpoints, which are these: (i) the composite rate of total (first and recurrent) HF hospitalizations and cardiovascular death during 24 months of follow-up, (ii) the rate of total (i.e. first and recurrent) HF hospitalizations within 24 months, and (iii) the change from baseline to 12 months in the Kansas City Cardiomyopathy Questionnaire overall score. The three primary endpoints will be analysed using the Hochberg procedure to control the familywise type I error rate across the three hypotheses. CONCLUSIONS: The RESHAPE-HF2 trial will provide sound evidence on the MitraClip device and its effects in HF patients with FMR. The recruitment was recently completed with 506 randomized patients.

Transition from asymptomatic to symptomatic systolic chronic heart failure: rationale and design of TransitionCHF.

AIMS: Chronic systolic heart failure (CHF) is a major health burden. A relevant number of patients shows asymptomatic left ventricular dysfunction (ALVSD) before symptomatic CHF or becomes asymptomatic after initiating heart failure therapy. Clinical course, prognosis, and response to pharmacological and device-based treatment are largely unknown in these two distinct groups of patients. Current pharmacological and interventional therapies do neither properly address the underlying pathophysiology nor prevent malignant loss of function. New therapeutic paradigms are needed to stop the progression from asymptomatic to symptomatic heart failure. Key questions are what causes progression of clinically asymptomatic New York Heart Association (NYHA) I heart failure to overt heart failure (>NYHA I) in some but not all patients and the underlying reasons for this transition. This requires the identification of disease mechanisms and biomarkers that predict outcome in well-defined cohorts for innovative preclinical and clinical trials. METHODS AND RESULTS: TransitionCHF is a prospective, multicentre, longitudinal pathophysiological evaluation cohort study in patients with asymptomatic systolic dysfunction NYHA I and left ventricular ejection fraction ≤40%. The cohort comprises both incidental findings and patients who had become asymptomatic after a previous symptomatic event. TransitionCHF has recruited 1000 patients with ALVSD caused by various aetiologies in 20 university heart failure clinics across Germany. Both patients with and without comorbidities at study entry will be recruited. Patients will be systematically investigated and followed up annually over the course of the study. The primary composite endpoint is time to hospitalization for heart failure and cardiovascular death. The secondary endpoints assess time to all-cause mortality, to cardiovascular mortality, to heart failure mortality, to all-cause hospitalization, to heart failure hospitalization, and to recurrent heart failure hospitalizations, as well as time to assist device implantation/transplantation. Additional investigations focusing on biomarkers, comorbidities, gender aspects, nutrition, and functional parameters including quality of life will be performed. CONCLUSIONS: TransitionCHF will provide a more thorough pathophysiological understanding of the progression of asymptomatic systolic dysfunction into symptomatic heart failure that will help develop therapies tailored to prevent progressive heart failure.

Rest and exercise-stress estimated pulmonary capillary wedge pressure using real-time free-breathing cardiovascular magnetic resonance imaging.

BACKGROUND: Identification of increased pulmonary capillary wedge pressure (PCWP) by right heart catheterization (RHC) is the reference standard for the diagnosis of heart failure with preserved ejection fraction (HFpEF). Recently, cardiovascular magnetic resonance (CMR) imaging estimation of PCWP at rest was introduced as a non-invasive alternative. Since many patients are only identified during physiological exercise-stress, we hypothesized that novel exercise-stress CMR-derived PCWP emerges superior compared to its assessment at rest. METHODS: The HFpEF-Stress Trial prospectively recruited 75 patients with exertional dyspnea and diastolic dysfunction who then underwent rest and exercise-stress RHC and CMR. HFpEF was defined according to PCWP (overt HFpEF ≥15 mmHg at rest, masked HFpEF ≥25 mmHg during exercise-stress). CMR-derived PCWP was calculated based on previously published formula using left ventricular mass and either biplane left atrial volume (LAV) or monoplane left atrial area (LAA). RESULTS: LAV (rest/stress: r = 0.50/r = 0.55, p < 0.001) and LAA PCWP (rest/stress: r = 0.50/r = 0.48, p < 0.001) correlated significantly with RHC-derived PCWP while numerically overestimating PCWP at rest and underestimating PCWP during exercise-stress. LAV and LAA PCWP showed good diagnostic accuracy to detect HFpEF (area under the receiver operating characteristic curve (AUC) LAV rest 0.73, stress 0.81; LAA rest 0.72, stress 0.77) with incremental diagnostic value for the detection of masked HFpEF using exercise-stress (AUC LAV rest 0.54 vs stress 0.67, p = 0.019, LAA rest 0.52 vs stress 0.66, p = 0.012). LAV but not LAA PCWP during exercise-stress was a predictor for 24 months hospitalization independent of a medical history for atrial fibrillation (hazard ratio (HR) 1.26, 95% confidence interval 1.02-1.55, p = 0.032). CONCLUSION: Non-invasive PCWP correlates well with the invasive reference at rest and during exercise stress. There is overall good diagnostic accuracy for HFpEF assessment using CMR-derived estimated PCWP despite deviations in absolute agreement. Non-invasive exercise derived PCWP may particularly facilitate detection of masked HFpEF in the future.

Impact of epicardial adipose tissue on cardiac function and morphology in patients with diastolic dysfunction.

AIMS: This study aimed to identify the impact of increased epicardial adipose tissue (EAT) and its regional distribution on cardiac function in patients with diastolic dysfunction. METHODS AND RESULTS: Sixty-eight patients with exertional dyspnoea (New York Heart Association ≥II), preserved ejection fraction (≥50%), and diastolic dysfunction (E/e' ≥ 8) underwent rest and stress right heart catheterization, transthoracic echocardiography, and cardiovascular magnetic resonance (CMR). EAT volumes were depicted from CMR short-axis stacks. First, the impact of increased EAT above the median was investigated. Second, the association of ventricular and atrial EAT with myocardial deformation at rest and during exercise stress was analysed in a multivariable regression analysis. Patients with high EAT had higher HFA-PEFF and H2FPEFF scores as well as N-terminal prohormone of brain natriuretic peptide levels (all P < 0.048). They were diagnosed with manifest heart failure with preserved ejection fraction (HFpEF) more frequently (low EAT: 37% vs. high EAT: 64%; P = 0.029) and had signs of adverse remodelling indicated by higher T1 times (P < 0.001). No differences in biventricular volumetry and left ventricular mass (all P > 0.074) were observed. Patients with high EAT had impaired atrial strain at rest and during exercise stress, and impaired ventricular strain during exercise stress. Regionally increased EAT was independently associated with functional impairment of the adjacent chambers. CONCLUSIONS: Patients with diastolic dysfunction and increased EAT show more pronounced signs of diastolic functional failure and adverse structural remodelling. Despite similar morphological characteristics, patients with high EAT show significant cardiac functional impairment, in particular in the atria. Our results indicate that regionally increased EAT directly induces atrial functional failure, which represents a distinct pathophysiological feature in HFpEF.

Prognostic and diagnostic implications of impaired rest and exercise-stress left atrial compliance in heart failure with preserved ejection fraction: Insights from the HFpEF stress trial.

BACKGROUND: With emerging therapies, early diagnosis of heart failure with preserved ejection fraction (HFpEF) comes to the fore. Whilst the reference standard of exercise-stress right heart catheterisation is well established, the clinical routine struggles between feasibility of exercise-stress and diagnostic accuracy of available tests. METHODS: The HFpEF Stress Trial (DZHK-17) prospectively enrolled 75 patients with exertional dyspnoea and echocardiographic signs of diastolic dysfunction (E/e' > 8) who underwent simultaneous rest and exercise-stress echocardiography and right heart catheterisation (RHC). HFpEF was defined according to pulmonary capillary wedge pressure (HFpEF: PCWP rest: ≥15 mmHg stress: ≥25 mmHg). Patients were classified as non-cardiac dyspnoea (NCD) in the absence of HFpEF and cardiovascular disease. LA compliance was defined as reservoir strain (Es)/(E/e'). Follow-up was conducted after 4 years to evaluate cardiovascular hospitalisation (CVH). RESULTS: The final study population included 68 patients (HFpEF n = 34 and NCD n = 34) of which 23 reached the clinical endpoint, 1 patient was lost to follow-up. Patients with HFpEF according to the HFA-PEFF score (≥5 points) had significantly lower LA compliance at rest (p < 0.001) compared to patients with a score ≤ 4. LA compliance at rest outperformed E/e' (AUC 0.78 vs 0.87, p = 0.024) and showed a statistical trend to outperform Es (AUC 0.79 vs 0.87, p = 0.090) for the diagnosis of HFpEF. LA compliance at rest predicted CVH (HR 2.83, 95% CI 1.70-4.74, p < 0.001) irrespective of concomitant atrial fibrillation. CONCLUSIONS: LA compliance at rest can be obtained from clinical routine imaging and bears strong diagnostic and prognostic accuracy. Addition of LA compliance can improve the role of echocardiography as the primary test and gatekeeper.

Circulating miR-let7a levels predict future diagnosis of chronic thromboembolic pulmonary hypertension.

Distinct patterns of circulating microRNAs (miRNAs) were found to be involved in misguided thrombus resolution. Thus, we aimed to investigate dysregulated miRNA signatures during the acute phase of pulmonary embolism (PE) and test their diagnostic and predictive value for future diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH). Microarray screening and subsequent validation in a large patient cohort (n = 177) identified three dysregulated miRNAs as potential biomarkers: circulating miR-29a and miR-720 were significantly upregulated and miR-let7a was significantly downregulated in plasma of patients with PE. In a second validation study equal expression patterns for miR-29a and miR-let7a regarding an acute event of recurrent venous thromboembolism (VTE) or deaths were found. MiR-let7a concentrations significantly correlated with echocardiographic and laboratory parameters indicating right ventricular (RV) dysfunction. Additionally, circulating miR-let7a levels were associated with diagnosis of CTEPH during follow-up. Regarding CTEPH diagnosis, ROC analysis illustrated an AUC of 0.767 (95% CI 0.54-0.99) for miR-let7a. Using logistic regression analysis, a calculated patient-cohort optimized miR-let7a cut-off value derived from ROC analysis of ≥ 11.92 was associated with a 12.8-fold increased risk for CTEPH. Therefore, miR-let7a might serve as a novel biomarker to identify patients with haemodynamic impairment and as a novel predictor for patients at risk for CTEPH.

Epicardial adipose tissue as an independent predictor of long-term outcome in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement.

BACKGROUND: Accurate risk stratification is important to improve patient selection and outcome of patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). As epicardial adipose tissue (EAT) is discussed to be involved in cardiovascular disease, it could be useful as a marker of poor prognosis in patients with severe AS undergoing TAVR. METHODS: A total of 416 patients diagnosed with severe AS by transthoracic echocardiography were assigned for TAVR and enrolled for systematic assessment. Patients underwent clinical surveys and 5-year long-term follow-up, with all-cause mortality as the primary endpoint. EAT volume was quantified on pre-TAVR planning CTs. Patients were retrospectively dichotomized at the median of 74 cm3 of EAT into groups with low EAT and high EAT volumes. Mortality rates were compared using Kaplan-Meyer plots and uni- and multivariable cox regression analyses. RESULTS: A total number of 341 of 416 patients (median age 80.9 years, 45% female) were included in the final analysis. Patients with high EAT volumes had similar short-term outcome (p = 0.794) but significantly worse long-term prognosis (p = 0.023) compared to patients with low EAT volumes. Increased EAT volumes were associated with worse long-term outcome (HR1.59; p = 0.031) independently from concomitant cardiovascular risk factors, general type of AS, and functional echocardiography parameters of AS severity (HR1.69; p = 0.013). CONCLUSION: Increased EAT volume is an independent predictor of all-cause mortality in patients with severe AS undergoing TAVR. It can be easily obtained from pre-TAVR planning CTs and may thus qualify as a novel marker to improve prognostication and management of patient with severe AS. TRIAL REGISTRATION: DRKS, DRKS00024479.

Histological assessment of cardiac amyloidosis in patients undergoing transcatheter aortic valve replacement.

AIMS: Studies have reported a strongly varying co-prevalence of aortic stenosis (AS) and cardiac amyloidosis (CA). We sought to histologically determine the co-prevalence of AS and CA in patients undergoing transcatheter aortic valve replacement (TAVR). Consequently, we aimed to derive an algorithm to identify cases in which to suspect the co-prevalence of AS and CA. METHODS AND RESULTS: In this prospective, monocentric study, endomyocardial biopsies of 162 patients undergoing TAVR between January 2017 and March 2021 at the University Medical Centre Göttingen were analysed by one pathologist blinded to clinical data using haematoxylin-eosin staining, Elastica van Gieson staining, and Congo red staining of endomyocardial biopsies. CA was identified in only eight patients (4.9%). CA patients had significantly higher N-terminal pro-brain natriuretic peptide (NT-proBNP) levels (4356.20 vs. 1938.00 ng/L, P = 0.034), a lower voltage-to-mass ratio (0.73 vs. 1.46 × 10-2 mVm2/g, P = 0.022), and lower transaortic gradients (Pmean 17.5 vs. 38.0 mmHg, P = 0.004) than AS patients. Concomitant CA was associated with a higher prevalence of post-procedural acute kidney injury (50.0% vs. 13.1%, P = 0.018) and sudden cardiac death [SCD; P (log-rank test) = 0.017]. Following propensity score matching, 184 proteins were analysed to identify serum biomarkers of concomitant CA. CA patients expressed lower levels of chymotrypsin (P = 0.018) and carboxypeptidase 1 (P = 0.027). We propose an algorithm using commonly documented parameters-stroke volume index, ejection fraction, NT-proBNP levels, posterior wall thickness, and QRS voltage-to-mass ratio-to screen for CA in AS patients, reaching a sensitivity of 66.6% with a specificity of 98.1%. CONCLUSIONS: The co-prevalence of AS and CA was lower than expected, at 4.9%. Despite excellent 1 year mortality, AS + CA patients died significantly more often from SCD. We propose a multimodal algorithm to facilitate more effective screening for CA containing parameters commonly documented during clinical routine. Proteomic biomarkers may yield additional information in the future.

Preclinical evaluation of CRISPR-based therapies for Noonan syndrome caused by deep-intronic LZTR1 variants.

Gene variants in LZTR1 are implicated to cause Noonan syndrome associated with a severe and early-onset hypertrophic cardiomyopathy. Mechanistically, LZTR1 deficiency results in accumulation of RAS GTPases and, as a consequence, in RAS-MAPK signaling hyperactivity, thereby causing the Noonan syndrome-associated phenotype. Despite its epidemiological relevance, pharmacological as well as invasive therapies remain limited. Here, personalized CRISPR-Cas9 gene therapies might offer a novel alternative for a curative treatment in this patient cohort. In this study, by utilizing a patient-specific screening platform based on iPSC-derived cardiomyocytes from two Noonan syndrome patients, we evaluated different clinically translatable therapeutic approaches using small Cas9 orthologs targeting a deep-intronic LZTR1 variant to cure the disease-associated molecular pathology. Despite high editing efficiencies in cardiomyocyte cultures transduced with lentivirus or all-in-one adeno-associated viruses, we observed crucial differences in editing outcomes in proliferative iPSCs vs. non-proliferative cardiomyocytes. While editing in iPSCs rescued the phenotype, the same editing approaches did not robustly restore LZTR1 function in cardiomyocytes, indicating critical differences in the activity of DNA double-strand break repair mechanisms between proliferative and non-proliferative cell types and highlighting the importance of cell type-specific screens for testing CRISPR-Cas9 gene therapies.

Angiotensin Receptor-Neprilysin Inhibition (Sacubitril/Valsartan) Reduces Structural Arterial Stiffness in Middle-Aged Mice.

BACKGROUND: Increasing arterial stiffness is a prominent feature of the aging cardiovascular system. Arterial stiffening leads to fundamental alterations in central hemodynamics with widespread detrimental implications for organ function resulting in significant morbidity and death, and specific therapies to address the underlying age-related structural arterial remodeling remain elusive. The present study investigates the potential of the recently clinically available dual angiotensin receptor-neprilysin inhibitor (ARNI) sacubitril/valsartan (LCZ696) to counteract age-related arterial fibrotic remodeling and stiffening in 1-year-old mice. METHODS AND RESULTS: Treatment of in 1-year-old mice with ARNI (sacubitril/valsartan), in contrast to angiotensin receptor blocker monotherapy (valsartan) and vehicle treatment (controls), significantly decreases structural aortic stiffness (as measured by in vivo pulse-wave velocity and ex vivo aortic pressure myography). This phenomenon appears, at least partly, independent of (indirect) blood pressure effects and may be related to a direct antifibrotic interference with aortic smooth muscle cell collagen production. Furthermore, we find aortic remodeling and destiffening due to ARNI treatment to be associated with improved parameters of cardiac diastolic function in aged mice. CONCLUSIONS: This study provides preclinical mechanistic evidence indicating that ARNI-based interventions may counteract age-related arterial stiffening and may therefore be further investigated as a promising strategy to improve cardiovascular outcomes in the elderly.