Lung ultrasound as a translational approach for non-invasive assessment of heart failure with reduced or preserved ejection fraction in mice

Aims: Heart failure (HF) has become an epidemic and constitutes a major medical, social, and economic problem worldwide. Despite advances in medical treatment, HF prognosis remains poor. The development of efficient therapies is hampered by the lack of appropriate animal models in which HF can be reliably determined, particularly in mice. The development of HF in mice is often assumed based on the presence of cardiac dysfunction, but HF itself is seldom proved. Lung ultrasound (LUS) has become a helpful tool for lung congestion assessment in patients at all stages of HF. We aimed to apply this non-invasive imaging tool to evaluate HF in mouse models of both systolic and diastolic dysfunction. Methods and results: We used LUS to study HF in a mouse model of systolic dysfunction, dilated cardiomyopathy, and in a mouse model of diastolic dysfunction, diabetic cardiomyopathy. LUS proved to be a reliable and reproducible tool to detect pulmonary congestion in mice. The combination of LUS and echocardiography allowed discriminating those mice that develop HF from those that do not, even in the presence of evident cardiac dysfunction. The study showed that LUS can be used to identify the onset of HF decompensation and to evaluate the efficacy of therapies for this syndrome. Conclusions: This novel approach in mouse models of cardiac disease enables for the first time to adequately diagnose HF non-invasively in mice with preserved or reduced ejection fraction, and will pave the way to a better understanding of HF and to the development of new therapeutic approaches.This study was supported by grants from the Spanish Ministerio de Economia y Competitividad (SAF2015-65722-R), Comunidad Autonoma de Madrid (2010-BMD2321, FIBROTEAM Consortium), European Union's FP7 (CardioNeT-ITN-289600, CardioNext-ITN-608027) and the Spanish Instituto de Salud Carlos III (CPII14/00027 to E.L-P, RD12/0042/0054 to B.I. and RD12/0042/066 to P.G.-P. and E.L-P). This work was also supported by the Plan Estatal de I+D+I 2013-2016 - European Regional Development Fund (FEDER) "A way of making Europe", Spain. The CNIC is supported by the Ministry of Economy, Industry and Competitiveness (MINECO) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (MINECO award SEV-2015-0505).S

Clinical phenotypes and prognosis of dilated cardiomyopathy caused by truncating variants in the TTN Gene.

Background: Truncating variants in the TTN gene (TTNtv) are the commonest cause of heritable dilated cardiomyopathy. This study aimed to study the phenotypes and outcomes of TTNtv carriers. Methods: Five hundred thirty-seven individuals (61% men; 317 probands) with TTNtv were recruited in 14 centers (372 [69%] with baseline left ventricular systolic dysfunction [LVSD]). Baseline and longitudinal clinical data were obtained. The primary end point was a composite of malignant ventricular arrhythmia and end-stage heart failure. The secondary end point was left ventricular reverse remodeling (left ventricular ejection fraction increase by ≥10% or normalization to ≥50%). Results: Median follow-up was 49 (18–105) months. Men developed LVSD more frequently and earlier than women (45±14 versus 49±16 years, respectively; P=0.04). By final evaluation, 31%, 45%, and 56% had atrial fibrillation, frequent ventricular ectopy, and nonsustained ventricular tachycardia, respectively. Seventy-six (14.2%) individuals reached the primary end point (52 [68%] end-stage heart failure events, 24 [32%] malignant ventricular arrhythmia events). Malignant ventricular arrhythmia end points most commonly occurred in patients with severe LVSD. Male sex (hazard ratio, 1.89 [95% CI, 1.04–3.44]; P=0.04) and left ventricular ejection fraction (per 10% decrement from left ventricular ejection fraction, 50%; hazard ratio, 1.63 [95% CI, 1.30–2.04]; P<0.001) were independent predictors of the primary end point. Two hundred seven of 300 (69%) patients with LVSD had evidence of left ventricular reverse remodeling. In a subgroup of 29 of 74 (39%) patients with initial left ventricular reverse remodeling, there was a subsequent left ventricular ejection fraction decrement. TTNtv location was not associated with statistically significant differences in baseline clinical characteristics, left ventricular reverse remodeling, or outcomes on multivariable analysis (P=0.07). Conclusions: TTNtv is characterized by frequent arrhythmia, but malignant ventricular arrhythmias are most commonly associated with severe LVSD. Male sex and LVSD are independent predictors of outcomes. Mutation location does not impact clinical phenotype or outcomes.pre-print1,66 M

Mitochondrial haplogroups associated with end-stage heart failure and coronary allograft vasculopathy in heart transplant patients

[Aims]: Mitochondrial haplogroups are known to influence individual predisposition to a wide spectrum of metabolic and degenerative diseases, including ischaemic cardiovascular diseases. We have examined the influence of the mitochondrial DNA (mtDNA) background on the development of human end-stage heart failure (HF) in patients undergoing heart transplantation. The influence of mtDNA haplogroups on the incidence of transplant-related complications, mainly cardiac allograft vasculopathy (CAV), and on post-transplant survival was also studied. [Methods and results]: The most common mitochondrial haplogroups in European populations were genotyped in 450 heart transplant recipients, 248 heart transplant donors, and 206 healthy controls. Mitochondrial haplogroups were determined by PCR amplification of short mtDNA fragments, followed by restriction fragment length polymorphism analysis. After adjustment for age and sex the frequency of haplogroup H was significantly higher in heart transplant recipients than in controls [OR: 1.86 (95 confidence intervals, CI: 1.272.74), P=0.014], and in heart donors [OR: 1.47 (95 CI: 0.992.19), P=0.032]. Likewise, haplogroup Uk was found significantly more frequently among CAV patients than in non-CAV heart allograft recipients [OR: 4.1 (95 CI: 1.51-11.42), P=0.042]. Finally, heart donor haplogroups had no influence on the morbidity or mortality after heart transplantation. [Conclusions]: Mitochondrial haplogroups behave like risk factors for the progress to end-stage HF in a Spanish cardiac transplant population. Mitochondrial DNA variants may have some influence on the appearance of cardiac transplant complications. © 2011 The Author.This work was supported by the Instituto de Salud Carlos III (ISCIII) (grant number PI 06/0205 to B.B. and PI 07/0167 to R.G.); Comunidad de Madrid (grant number GEN-0269/2006 to R.G.); Ministerio de Ciencia e Innovación (SAF2010-22153-C03-03 to C.V.); and Sociedad Española de Cardiología (2008 to M.G.B.). M.E.G. is a Senior Fellow and receives grant support from the Center for Biomedical Research on Rares Diseases (CIBERER); M.E.V. is a Junior Fellow and receives grant support from REDINSCOR, a clinical and scientific research network on heart failure supported by ISCIII.Peer Reviewe

Development and Validation of a Prediction Model and Score for Transthyretin Cardiac Amyloidosis Diagnosis: T-Amylo.

BACKGROUND Although transthyretin cardiac amyloidosis (ATTR-CA) is often underdiagnosed, clinical suspicion is essential for early diagnosis. OBJECTIVES The aim of this study was to develop and validate a feasible prediction model and score to facilitate the diagnosis of ATTR-CA. METHODS This retrospective multicenter study enrolled consecutive patients who underwent 99mTc-DPD scintigraphy for suspected ATTR-CA. ATTR-CA was diagnosed if Grade 2 or 3 cardiac uptake was evidenced on 99mTc-DPD scintigraphy in the absence of a detectable monoclonal component or by demonstration of amyloid by biopsy. A prediction model for ATTR-CA diagnosis was developed in a derivation sample of 227 patients from 2 centers using multivariable logistic regression with clinical, electrocardiography, analytical, and transthoracic echocardiography variables. A simplified score was also created. Both of them were validated in an external cohort (n = 895) from 11 centers. RESULTS The obtained prediction model combined age, gender, carpal tunnel syndrome, interventricular septum in diastole thickness, and low QRS interval voltages, with an area under the curve (AUC) of 0.92. The score had an AUC of 0.86. Both the T-Amylo prediction model and the score showed a good performance in the validation sample (ie, AUC: 0.84 and 0.82, respectively). They were tested in 3 clinical scenarios of the validation cohort: 1) hypertensive cardiomyopathy (n = 327); 2) severe aortic stenosis (n = 105); and 3) heart failure with preserved ejection fraction (n = 604), all with good diagnostic accuracy. CONCLUSIONS The T-Amylo is a simple prediction model that improves the prediction of ATTR-CA diagnosis in patients with suspected ATTR-CA.Part of this project was funded by Pfizer through an independent general research grant (number 64764667). This study has been partially funded by Instituto de Salud Carlos III through the project "PI20/01379” (co-funded by European Regional Development Fund/ European Social Fund "A way to make Europe"/"Investing in your future"). The CNIC is supported by the ISCIII, MCIN, the Pro-CNIC Foundation, and the Severo Ochoa grant (CEX2020-001041-S). Dr Basurte Elorz has received a consultant fee from Pfizer. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.S

β3 adrenergic agonist treatment in chronic pulmonary hypertension associated with heart failure (SPHERE-HF): a double blind, placebo-controlled, randomized clinical trial.

AIMS Pulmonary hypertension (PH) associated with left heart disease is an increasingly prevalent problem, orphan of targeted therapies, and related to a poor prognosis, particularly when pre- and post-capillary PH combine. The current study aimed to determine whether treatment with the selective β3 adrenoreceptor agonist mirabegron improves outcomes in patients with combined pre- and post-capillary PH (CpcPH). METHODS AND RESULTS The β3 Adrenergic Agonist Treatment in Chronic Pulmonary Hypertension Secondary to Heart Failure (SPHERE-HF) trial is a multicentre, randomized, parallel, placebo-controlled clinical trial that enrolled stable patients with CpcPH associated with symptomatic heart failure. A total of 80 patients were assigned to receive mirabegron (50 mg daily, titrated till 200 mg daily, n = 39) or placebo (n = 41) for 16 weeks. Of them, 66 patients successfully completed the study protocol and were valid for the main analysis. The primary endpoint was the change in pulmonary vascular resistance (PVR) on right heart catheterization. Secondary outcomes included the change in right ventricular (RV) ejection fraction by cardiac magnetic resonance or computed tomography, other haemodynamic variables, functional class, and quality of life. The trial was negative for the primary outcome (placebo-corrected mean difference of 0.62 Wood units, 95% confidence interval [CI] -0.38, 1.61, p = 0.218). Patients receiving mirabegron presented a significant improvement in RV ejection fraction as compared to placebo (placebo-corrected mean difference of 3.0%, 95% CI 0.4, 5.7%, p = 0.026), without significant differences in other pre-specified secondary outcomes. CONCLUSIONS SPHERE-HF is the first clinical trial to assess the potential benefit of β3 adrenergic agonists in PH. The trial was negative since mirabegron did not reduce PVR, the primary endpoint, in patients with CpcPH. On pre-specified secondary outcomes, a significant improvement in RV ejection fraction assessed by advanced cardiac imaging was found, without differences in functional class or quality of life.The SPHERE-HF trial is an investigator-initiated noncommercial trial independent of the pharmaceutical industry. This work was funded by a grant from Fundació La Marató de TV3 (20151730-31-32) to A.G.-A. as the coordinator. A.G.A. was granted by Instituto de Salud Carlos III INT19/00022, PI17/00995 and PI20/00742 during the study period. B.I. is funded by the European Commission (ERC-Consolidator Grant agreement No. 819775), the Spanish Ministry of Science and Innovation (PID2019-110369RB-I00), and the Comunidad de Madrid (S2017/BMD-3867 RENIM-CM). The CNIC is supported by the Ministerio de Ciencia, Innovación y Universidades and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (CEX2020-001041-S). CNIC imaging facilities are part of the ICTS ReDIB. IDIBAPS belongs to the CERCA Programme and receives partial funding from the Generalitat de Catalunya. The study funders were not involved in the study design; the collection, analysis, or interpretation of data; the writing of the manuscript; or the decision to submit the paper to publication. Conflict of interest: CNIC and Fundació Clínic per a la recerca biomèdica hold a patent for the use of beta-3 agonists for the treatment of pulmonary hypertension (B.I., A.G.A., and V.F. are co-inventors). All other authors have nothing to disclose.S

Formin Homology 2 Domain Containing 3 (FHOD3) Is a Genetic Basis for Hypertrophic Cardiomyopathy.

The genetic cause of hypertrophic cardiomyopathy remains unexplained in a substantial proportion of cases. Formin homology 2 domain containing 3 (FHOD3) may have a role in the pathogenesis of cardiac hypertrophy but has not been implicated in hypertrophic cardiomyopathy. This study sought to investigate the relation between FHOD3 mutations and the development of hypertrophic cardiomyopathy. FHOD3 was sequenced by massive parallel sequencing in 3,189 hypertrophic cardiomyopathy unrelated probands and 2,777 patients with no evidence of cardiomyopathy (disease control subjects). The authors evaluated protein-altering candidate variants in FHOD3 for cosegregation, clinical characteristics, and outcomes. The authors identified 94 candidate variants in 132 probands. The variants' frequencies were significantly higher in patients with hypertrophic cardiomyopathy (74 of 3,189 [2.32%]) than in disease control subjects (18 of 2,777 [0.65%]; p  FHOD3 is a novel disease gene in hypertrophic cardiomyopathy, accounting for approximately 1% to 2% of cases. The phenotype and the rate of cardiovascular events are similar to those reported in unselected cohorts. The FHOD3 gene should be routinely included in hypertrophic cardiomyopathy genetic testing panels