Editorial for "Remodeling in Aortic Stenosis With Reduced and Preserved Ejection Fraction: Insight on Motion Abnormality Via 3D+Time Personalized LV Modelling in Cardiac MRI"

Level of Evidence

5

Technical Efficacy Stage

2

Accurate diagnosis of apical hypertrophic cardiomyopathy using explainable advanced electrocardiogram analysis

AIMS

Typical electrocardiogram (ECG) features of apical hypertrophic cardiomyopathy (ApHCM) include tall R waves and deep or giant T-wave inversion in the precordial leads, but these features are not always present. The ECG is used as the gatekeeper to cardiac imaging for diagnosis. We tested whether explainable advanced ECG (A-ECG) could accurately diagnose ApHCM.

METHODS AND RESULTS

Advanced ECG analysis was performed on standard resting 12-lead ECGs in patients with ApHCM [n = 75 overt, n = 32 relative (<15 mm hypertrophy); a subgroup of which underwent cardiovascular magnetic resonance (n = 92)], and comparator subjects (n = 2449), including healthy volunteers (n = 1672), patients with coronary artery disease (n = 372), left ventricular electrical remodelling (n = 108), ischaemic (n = 114) or non-ischaemic cardiomyopathy (n = 57), and asymmetrical septal hypertrophy HCM (n = 126). Multivariable logistic regression identified four A-ECG measures that together discriminated ApHCM from other diseases with high accuracy [area under the receiver operating characteristic (AUC) curve (bootstrapped 95% confidence interval) 0.982 (0.965-0.993)]. Linear discriminant analysis also diagnosed ApHCM with high accuracy [AUC 0.989 (0.986-0.991)].

CONCLUSION

Explainable A-ECG has excellent diagnostic accuracy for ApHCM, even when the hypertrophy is relative, with A-ECG analysis providing incremental diagnostic value over imaging alone. The electrical (ECG) and anatomical (wall thickness) disease features do not completely align, suggesting that future diagnostic and management strategies may incorporate both features.

Stromal Cell-SLIT3/Cardiomyocyte-ROBO1 Axis Regulates Pressure Overload-Induced Cardiac Hypertrophy

BACKGROUND

Recently shown to regulate cardiac development, the secreted axon guidance molecule SLIT3 maintains its expression in the postnatal heart. Despite its known expression in the cardiovascular system after birth, SLIT3's relevance to cardiovascular function in the postnatal state remains unknown. As such, the objectives of this study were to determine the postnatal myocardial sources of SLIT3 and to evaluate its functional role in regulating the cardiac response to pressure overload stress.

METHODS

We performed in vitro studies on cardiomyocytes and myocardial tissue samples from patients and performed in vivo investigation with SLIT3 and ROBO1 (roundabout homolog 1) mutant mice undergoing transverse aortic constriction to establish the role of SLIT3-ROBO1 in adverse cardiac remodeling.

RESULTS

We first found that SLIT3 transcription was increased in myocardial tissue obtained from patients with congenital heart defects that caused ventricular pressure overload. Immunostaining of hearts from WT (wild-type) and reporter mice revealed that SLIT3 is secreted by cardiac stromal cells, namely fibroblasts and vascular mural cells, within the heart. Conditioned media from cardiac fibroblasts and vascular mural cells both stimulated cardiomyocyte hypertrophy in vitro, an effect that was partially inhibited by an anti-SLIT3 antibody. Also, the N-terminal, but not the C-terminal, fragment of SLIT3 and the forced overexpression of SLIT3 stimulated cardiomyocyte hypertrophy and the transcription of hypertrophy-related genes. We next determined that ROBO1 was the most highly expressed roundabout receptor in cardiomyocytes and that ROBO1 mediated SLIT3's hypertrophic effects in vitro. In vivo, Tcf21+ fibroblast and Tbx18+ vascular mural cell-specific knockout of SLIT3 in mice resulted in decreased left ventricular hypertrophy and cardiac fibrosis after transverse aortic constriction. Furthermore, α-MHC+ cardiomyocyte-specific deletion of ROBO1 also preserved left ventricular function and abrogated hypertrophy, but not fibrosis, after transverse aortic constriction.

CONCLUSIONS

Collectively, these results indicate a novel role for the SLIT3-ROBO1-signaling axis in regulating postnatal cardiomyocyte hypertrophy induced by pressure overload.

[Predictive value of cardiac magnetic resonance imaging for adverse left ventricular remodeling after acute ST-segment elevation myocardial infarction]

OBJECTIVE

To assess the value of cardiac magnetic resonance (CMR) imaging for predicting adverse left ventricular remodeling in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

We retrospectively analyzed the clinical data and serial CMR (cine and LGE sequences) images of 86 STEMI patients within 1 week and 5 months after percutaneous coronary intervention (PCI), including 25 patients with adverse LV remodeling and 61 without adverse LV remodeling, defined as an increase of left ventricular end-systolic volume (LVESV) over 15% at the second CMR compared to the initial CMR. The CMR images were analyzed for LV volume, infarct characteristics, and global and infarct zone myocardial function. The independent predictors of adverse LV remodeling following STEMI were analyzed using univariate and multivariate Logistic regression methods.

RESULTS

The initial CMR showed no significant differences in LV volume or LV ejection fraction (LVEF) between the two groups, but the infarct mass and microvascular obstructive (MVO) mass were significantly greater in adverse LV remodeling group (P < 0.05). Myocardial injury and cardiac function of the patients recovered over time in both groups. At the second CMR, the patients with adverse LV remodeling showed a significantly lower LVEF, a larger left ventricular end-systolic volume index (LVESVI) and a greater extent of infarct mass (P < 0.001) with lower global peak strains and strain rates in the radial, circumferential, and longitudinal directions (P < 0.05), infarct zone peak strains in the 3 directions, and infarct zone peak radial and circumferential strain rates (P < 0.05). The independent predictors for adverse LV remodeling following STEMI included the extent of infarct mass (AUC=0.793, 95% CI: 0.693-0.873; cut-off value: 30.67%), radial diastolic peak strain rate (AUC=0.645, 95% CI: 0.534-0.745; cut-off value: 0.58%), and RAAS inhibitor (AUC= 0.699, 95% CI: 0.590-0.793).

CONCLUSION

The extent of infarct mass, peak radial diastolic strain rate, and RAAS inhibitor are independent predictors of adverse LV remodeling following STEMI.

Recurrence After Atrial Fibrillation Ablation and Investigational Biomarkers of Cardiac Remodeling

BACKGROUND

Recurrence after atrial fibrillation (AF) ablation remains common. We evaluated the association between recurrence and levels of biomarkers of cardiac remodeling, and their ability to improve recurrence prediction when added to a clinical prediction model.

METHODS AND RESULTS

Blood samples collected before de novo catheter ablation were analyzed. Levels of bone morphogenetic protein-10, angiopoietin-2, fibroblast growth factor-23, insulin-like growth factor-binding protein-7, myosin-binding protein C3, growth differentiation factor-15, interleukin-6, N-terminal pro-brain natriuretic peptide, and high-sensitivity troponin T were measured. Recurrence was defined as ≥30 seconds of an atrial arrhythmia 3 to 12 months postablation. Multivariable logistic regression was performed using biomarker levels along with clinical covariates: APPLE score (Age >65 years, Persistent AF, imPaired eGFR [<60 ml/min/1.73m2], LA diameter ≥43 mm, EF <50%; which includes age, left atrial diameter, left ventricular ejection fraction, persistent atrial fibrillation, and estimated glomerular filtration rate), preablation rhythm, sex, height, body mass index, presence of an implanted continuous monitor, year of ablation, and additional linear ablation. A total of 1873 participants were included. A multivariable logistic regression showed an association between recurrence and levels of angiopoietin-2 (odds ratio, 1.08 [95% CI, 1.02-1.15], P=0.007) and interleukin-6 (odds ratio, 1.02 [95% CI, 1.003-1.03]; P=0.02). The area under the receiver operating characteristic curve of a model that only contained clinical predictors was 0.711. The addition of any of the 9 studied biomarkers to the predictive model did not result in a statistically significant improvement in the area under the receiver operating characteristic curve.

CONCLUSIONS

Higher angiopoietin-2 and interleukin-6 levels were associated with recurrence after atrial fibrillation ablation in multivariable modeling. However, the addition of biomarkers to a clinical prediction model did not significantly improve recurrence prediction.

Kielin/chordin-like protein deficiency aggravates pressure overload-induced cardiac dysfunction and remodeling via P53/P21/CCNB1 signaling in mice

Targeting cardiac remodeling is regarded as a key therapeutic strategy for heart failure. Kielin/chordin-like protein (KCP) is a secretory protein with 18 cysteine-rich domains and associated with kidney and liver fibrosis. However, the relationship between KCP and cardiac remodeling remains unclear. Here, we aimed to investigate the role of KCP in cardiac remodeling induced by pressure overload and explore its potential mechanisms. Left ventricular (LV) KCP expression was measured with real-time quantitative PCR, western blotting, and immunofluorescence staining in pressure overload-induced cardiac remodeling in mice. Cardiac function and remodeling were evaluated in wide-type (WT) mice and KCP knockout (KO) mice by echocardiography, which were further confirmed by histological analysis with hematoxylin and eosin and Masson staining. RNA sequence was performed with LV tissue from WT and KO mice to identify differentially expressed genes and related signaling pathways. Primary cardiac fibroblasts (CFs) were used to validate the regulatory role and potential mechanisms of KCP during fibrosis. KCP was down-regulated in the progression of cardiac remodeling induced by pressure overload, and was mainly expressed in fibroblasts. KCP deficiency significantly aggravated pressure overload-induced cardiac dysfunction and remodeling. RNA sequence revealed that the role of KCP deficiency in cardiac remodeling was associated with cell division, cell cycle, and P53 signaling pathway, while cyclin B1 (CCNB1) was the most significantly up-regulated gene. Further investigation in vivo and in vitro suggested that KCP deficiency promoted the proliferation of CFs via P53/P21/CCNB1 pathway. Taken together, these results suggested that KCP deficiency aggravates cardiac dysfunction and remodeling induced by pressure overload via P53/P21/CCNB1 signaling in mice.

Gabapentin attenuates cardiac remodeling after myocardial infarction by inhibiting M1 macrophage polarization through the peroxisome proliferator-activated receptor-γ pathway

OBJECTIVES

Inflammation regulates ventricular remodeling after myocardial infarction (MI), and gabapentin exerts anti-inflammatory effects. We investigated the anti-inflammatory role and mechanism of gabapentin after MI.

METHODS

Rats were divided into the sham group (n = 12), MI group (n = 20), and MI + gabapentin group (n = 16). MI was induced by left coronary artery ligation. The effects of gabapentin on THP-1-derived macrophages were examined in vitro.

RESULTS

In vivo, 1 week after MI, gabapentin significantly reduced inducible nitric oxide synthase (iNOS; M1 macrophage marker) expression and decreased pro-inflammatory factors (tumor necrosis factor [TNF]-α and interleukin [IL]-1β). Gabapentin upregulated the M2 macrophage marker arginase-1, as well as CD163 expression, and increased the expression of anti-inflammatory factors, including chitinase-like 3, IL-10, and transforming growth factor-β. Four weeks after MI, cardiac function, infarct size, and cardiac fibrosis improved after gabapentin treatment. Gabapentin inhibited sympathetic nerve activity and decreased ventricular electrical instability in rats after MI. Tyrosine hydroxylase and growth-associated protein 43 were suppressed after gabapentin treatment. Gabapentin downregulated nerve growth factor (NGF) and reduced pro-inflammatory factors (iNOS, TNF-α, and IL-1β). In vitro, gabapentin reduced NGF, iNOS, TNF-α, and IL-1β expression in lipopolysaccharide-stimulated macrophages. Mechanistic studies revealed that the peroxisome proliferator-activated receptor-γ antagonist GW9662 attenuated the effects of gabapentin. Moreover, gabapentin reduced α2δ1 expression in the macrophage plasma membrane and reduced the calcium content of macrophages.

CONCLUSION

Gabapentin attenuates cardiac remodeling by inhibiting inflammation via peroxisome proliferator-activated receptor-γ activation and preventing calcium overload.

COMPArison of Multi-Point Pacing and ConvenTional Cardiac Resynchronization Therapy Through Noninvasive Hemodynamics Measurement: Short- and Long-Term Results of the COMPACT-MPP Study

Invasive hemodynamic studies have shown improved left ventricular (LV) performances when cardiac resynchronization therapy/defibrillator is delivered through multipoint pacing (MPP). Nowadays, strategies have become available that allow studying the same hemodynamic parameters at a noninvasive level. The aim of the present study was to evaluate the clinical implication of using a patient-tailored approach for cardiac resynchronization therapy programming based on noninvasively assessed LV hemodynamics to identify the best biventricular pacing modality between standard single-site pacing (STD) and MPP for each patient. Therefore, 51 patients with heart failure (age 69 ± 9 years, 35 men, 27% ischemic etiology) implanted with cardiac resynchronization therapy/defibrillator underwent noninvasive LV function assessment through photoplethysmography before hospital discharge for addressing dP/dt and stroke volume in both pacing modalities (STD and MPP). The modality that performed better in terms of hemodynamic improvement was permanently programmed. Global longitudinal strain (GLS) was also assessed, and repeated at 3 months. Compared with intrinsic rhythm (928 ± 486 mm Hg/s), dP/dtmax showed a trend to increase in both biventricular pacing modes (1,000 ± 577 mm Hg/s in STD, 1,036 ± 530 mm Hg/s in MPP, p = NS). MPP was associated with a wider hemodynamic improvement than was STD and was the modality of choice in 34 of 51 patients (67%). GLS at predischarge did not differ between groups (-10.3 ± 3.8% vs -10.2 ± 3.5%), but significant improvement of ejection fraction at 1 month (34.4 ± 5.3%, p <0.001) and of GLS at 3 months (-12.9 ± 2.9%, p <0.005) was observed across the entire cohort. At 3 months, 77% of patients were classified as responders. Interestingly, long-term (3 years) follow-up unveiled a reduction in all-cause mortality in the MPP group compared with the STD group. In conclusion, cardiac resynchronization therapy programming guided by acute noninvasive hemodynamics favored MPP modality and caused short-term LV positive remodeling and improved long-term outcomes. Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT04299360.

Human amniotic MSCs-mediated anti-inflammation of CD206hiIL-10hi macrophages alleviates isoproterenol-induced ventricular remodeling in mice

BACKGROUND

Human amniotic mesenchymal stem cells (hAMSCs) derived from amniotic membrane have multilineage differentiation, immunosuppressive, and anti-inflammation which makes them suitable for the treatment of various diseases.

OBJECTIVE

This study aimed to explore the therapeutic effect and molecular mechanism of hAMSCs in ventricular remodeling (VR).

METHODS

hAMSCs were characterized by a series of experiments such as flow cytometric analysis, immunofluorescence, differentiative induction and tumorigenicity. Mouse VR model was induced by isoproterenol (ISO) peritoneally, and the therapeutic effects and the potential mechanisms of hAMSCs transplantation were evaluated by echocardiography, carboxy fluorescein diacetate succinimidyl ester (CFSE) labeled cell tracing, histochemistry, qRT-PCR and western blot analysis. The co-culturing experiments were carried out for further exploring the mechanisms of hAMSCs-derived conditioned medium (CM) on macrophage polarization and fibroblast fibrosis in vitro.

RESULTS

hAMSCs transplantation significantly alleviated ISO-induced VR including cardiac hypertrophy and fibrosis with the improvements of cardiac functions. CFSE labeled hAMSCs kept an undifferentiated state in heart, indicating that hAMSCs-mediated the improvement of ISO-induced VR might be related to their paracrine effects. hAMSCs markedly inhibited ISO-induced inflammation and fibrosis, seen as the increase of M2 macrophage infiltration and the expressions of CD206 and IL-10, and the decreases of CD86, iNOS, COL3 and αSMA expressions in heart, suggesting that hAMSCs transplantation promoted the polarization of M2 macrophages and inhibited the polarization of M1 macrophages. Mechanically, hAMSCs-derived CM significantly increased the expressions of CD206, IL-10, Arg-1 and reduced the expressions of iNOS and IL-6 in RAW264.7 macrophages in vitro. Interestingly, RAW264.7-CM remarkably promoted the expressions of anti-inflammatory factors such as IL-10, IDO, and COX2 in hAMSCs. Furthermore, the CM derived from hAMSCs pretreated with RAW264.7-CM markedly inhibited the expressions of fibrogenesis genes such as αSMA and COL3 in 3T3 cells.

CONCLUSION

Our results demonstrated that hAMSCs effectively alleviated ISO-induced cardiac hypertrophy and fibrosis, and improved the cardiac functions in mice, and the underlying mechanisms might be related to inhibiting the inflammation and fibrosis during the ventricular remodeling through promoting the polarization of CD206hiIL-10hi macrophages in heart tissues. Our study strongly suggested that by taking the advantages of the potent immunosuppressive and anti-inflammatory effects, hAMSCs may provide an alternative therapeutic approach for prevention and treatment of VR clinically.

Crosstalk between endothelial cells with a non-canonical EndoMT phenotype and cardiomyocytes/fibroblasts via IGFBP5 aggravates TAC-induced cardiac dysfunction

Heart failure (HF) is a complex chronic condition characterized by structural and functional impairments. The differentiation of endothelial cells into myofibroblasts (EndoMT) in response to cardiac fibrosis is controversial, and the relative contribution of endothelial plasticity remains to be explored. Single-cell RNA sequencing was used to identify endothelial cells undergoing fibrotic differentiation within 2 weeks of transverse aortic constriction (TAC). This subset of endothelial cells transiently expressed fibrotic genes but had low expression of alpha-smooth muscle actin, indicating a non-canonical EndoMT, which we named a transient fibrotic-like phenotype (EndoFP). The role of EndoFP in pathological cardiac remodeling may be correlated with increased levels of osteopontin. Cardiomyocytes and fibroblasts co-cultured with EndoFP exhibited heightened pro-hypertrophic and pro-fibrotic effects. Mechanistically, we found that the upregulated expression of insulin-like growth factor-binding protein 5 may be a key mediator of EndoFP-induced cardiac dysfunction. Furthermore, our findings suggested that Rab5a is a novel regulatory gene involved in the EndoFP process. Our study suggests that the specific endothelial subset identified in TAC-induced pressure overload plays a critical role in the cellular interactions that lead to cardiac fibrosis and hypertrophy. Additionally, our findings provide insight into the mechanisms underlying EndoFP, making it a potential therapeutic target for early heart failure.

Factors associated with changes in echocardiographic parameters following kidney transplantation

BACKGROUND

Chronic kidney disease leads to cardiac remodelling of multifactorial origin known as "uraemic cardiomyopathy", the reversibility of which after kidney transplantation (KT) remains controversial. Our objectives were to assess, in the modern era, changes in echocardiographic parameters following KT and identify predictive clinical and biological factors associated with echocardiographic changes.

METHODS

One hundred six patients (mean age 48 ± 16, 73% male) who underwent KT at the University Hospital of Nancy between 2007 and 2018 were retrospectively investigated. Pre- and post-KT echocardiography findings (8.6 months before and 22 months after KT on average, respectively) were centralised, blind-reviewed and compared.

RESULTS

A majority of patients (60%) had either a left ventricular (LV) ejection fraction < 50%, at least moderately abnormal LV mass index or left atrial (LA) dilatation at pretransplanted echocardiography. After KT, LV remodelling and diastolic doppler indices did not significantly change whereas LA volume index (LAVI) increased (35.9 mL/m2 post-KT vs. 30.9 mL/m2 pre-KT, p = 0.006). Advancing age, cardiac valvular disease, delayed graft function, lower post-KT haemoglobin, and more severe post-KT hypertension were associated with higher LAVI after KT. Higher post-KT serum creatinine, more severe post-KT hypertension and lower pre-KT blood calcium levels were associated with a deterioration in LAVI after KT.

DISCUSSION/CONCLUSION

Adverse remodelling of the left atrial volume occurred after KT, predominantly in patients with lower pre-KT blood calcium, poorer graft function and post-KT hypertension. These results suggest that a better management of modifiable factors such as pre-KT hyperparathyroidism or post-KT hypertension could limit post-KT cardiac remodelling.

High serum fibroblast growth factor 21 levels were related to the prognosis and ventricular remodeling of heart failure patients with mildly reduced and reduced ejection fraction

INTRODUCTION

Previous studies have shown that fibroblast growth factor 21 (FGF21) is involved in the ventricular remodeling process in heart failure with preserved ejection fraction (HFpEF). We hypothesized that high levels of FGF21 correlated with the ventricular remodeling of heart failure patients with mildly reduced (HFmrEF) and reduced ejection fraction (HFrEF).

METHODS

A total of 203 participants with HFmrEF or HFrEF were enrolled and followed up from June 2018 to June 2021. 68 subjects without heart failure (HF) underwent physical examinations during the same time were selected as the control group. The primary endpoint was the occurrence of major adverse cardiovascular events (MACEs), which were defined as all-cause or cardiac mortality and rehospitalization for decompensation. Serum FGF21 levels were measured early the next morning after admission using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The FGF21 levels were significantly higher in patients with HFmrEF or HFrEF than that in the control group (213.57 ± 42.65 pg/mL, 222.93 ± 34.36 pg/mL vs 171.00 ± 12.86 pg/mL, p < .001). The serum levels of FGF21 and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were both higher in the endpoint event group than those of non-endpoint event group regardless of the HFmrEF or HFrEF group (p < .001). Spearman's correlation revealed that FGF21 was positively correlated with left ventricular end-systolic diameter left ventricular end-diastolic diameter left ventricular mass index (p < .01). Moreover, there was a negative correlation between FGF21 and left ventricular ejection fraction in addition to relative wall thickness (p < .001). The area under the receiver operating characteristic (ROC) curve (AUC) of FGF21 was 0.874. The optimal cut-off value of FGF21 determined by ROC curve was 210.11 pg/mL. The Kaplan-Meier analysis demonstrated that the low FGF21 levels group had an increased MACE-free survival rate compared with the high FGF21 levels group. On univariate and multivariate Cox analysis, it was seen that both serum FGF21 and NT-proBNP were independent predictors of a poor prognosis in HF patients.

CONCLUSION

Baseline levels of FGF21 and NT-proBNP were related to the ventricular remodeling of patients with a mildly reduced or reduced ejection fraction. FGF21 and NT-proBNP both had good prognostic value for MACEs in heart failure patients with a mildly reduced and reduced ejection fraction.

Relationship between ODI and sleep structure of obstructive sleep apnea and cardiac remodeling

PURPOSE

The purpose of the study was to evaluate the quantitative relationship between Oxygen Desaturation Index (ODI) and sleep structure of obstructive sleep apnea (OSA) and cardiac remodeling.

METHODS

In this study, patients were enrolled from January 2015 to October 2022, and were divided into 3 groups according to AHI: patients with AHI < 15, patients with 15 ≤ AHI < 30, and 260 patients with AHI ≥ 30. Stratified linear regression was used to analyze independent risk factors for cardiac remodeling in OSA.

RESULTS

A total of 479 patients were enrolled. We found that compared with AHI < 15 group (n = 120), the group with AHI > 30 (n = 260) had increased left atrial anteroposterior diameter, left ventricular end-diastolic internal diameter, left ventricular posterior wall thickness, right ventricular anteroposterior diameter, and interventricular septal thickness (P < 0.05). The group with 15 ≤ AHI ≤ 30 (n = 99) had increased left atrial anteroposterior diameter (P < 0.05). Multivariate linear regression revealed that N2 sleep was an independent risk factor for left ventricular posterior wall thickness, with positive correlation (p < 0.05). N3 sleep was an independent risk factor for transverse right atrial diameter and right ventricular anteroposterior diameter, with negative correlation (P < 0.05). ODI was an independent risk factor for interventricular septal thickness, with positive correlation (P < 0.05). The arousal index was an independent risk factor for increased left atrial anteroposterior diameter, with positive correlation (P < 0.05).

CONCLUSIONS

Increased ODI is an independent risk factor for interventricular septal thickness, while decreased slow wave sleep is an independent risk factor for right heart remodeling in OSA.

Granzyme B PET imaging inflammation and remodeling in myocardial infarction

PURPOSE

This study aimed to evaluate whether granzyme B (GzmB)-targeted positron emission tomography (PET) imaging agent (68 Ga-grazytracer) can characterize cardiac inflammation and remodeling in myocardial infarction (MI).

METHODS

Rats with MI were subjected to GzmB-targeted PET/CT on post-operative days 1, 3, 6, 14, and 28. Autoradiography, Masson staining, immunohistochemistry, and ELISA were performed to verify the inflammatory response and remodeling after MI in vitro. Rats were treated with GzmB inhibitor Z-IETD-FMK to improve cardiac remodeling. Cardiac function tests were performed by echocardiography at 6 weeks after MI.

RESULTS

The highest uptake of 68 Ga-grazytracer was observed on day 3 after MI compared with the values obtained on the other days (0.294 ± 0.03% ID/g at 3 days vs. 0.122 ± 0.01% ID/g in the sham group, P < 0.001). Immunohistochemistry showed significantly high expression of GzmB and CD8, in line with the PET/CT imaging results. Autoradiography revealed 68 Ga-grazytracer accumulation in the infarcted myocardium. The 68 Ga-grazytracer uptake of treated rats was significantly reduced compared with that in the MI groups (0.184 ± 0.03%ID/g vs. 0.286 ± 0.03%ID/g; P < 0.001). Echocardiography showed that the left ventricular ejection fraction was lower in the MI groups than in the ischemia reperfusion group. GzmB inhibitor treatment was shown to be effective in improving cardiac function without significantly shortening infarct size.

CONCLUSIONS

This study demonstrated the potential of 68 Ga-grazytracer imaging to delineate adverse inflammatory responses and pathological cardiac remodeling, which can help predict heart function. PET/CT imaging-guided therapy may reduce myocardial injury and improve heart function in MI.

Association Between Elevated Body Mass Index and Cardiac Organ Damage in Children and Adolescents: Evidence and Mechanisms

INTRODUCTION

Although a number of pathophysiological aspects of childhood obesity have been reported, few information are available on obesity-related cardiac organ damage.

AIM

The present study was aimed at assessing the impact of anthropometric, blood pressure (BP) and metabolic variable on cardiac structure and function in youth.

METHODS

In 78 subjects aged 5-16 years attending the outpatient clinic of cardiovascular risk (Valencia, Spain) anthropometric and metabolic variables, clinic and ambulatory BP and echocardiographic parameters were assessed. Subjects were also classified according to the presence of insulin resistance.

RESULTS

Subjects mean age (± SD) amounted to 12.03 ± 2.4 years and males to 53.8%. Ten subjects were normoweight, 11 overweight, 39 obese, and 18 severely obese. No significant difference in office and ambulatory BP was detected among different bodyweight groups. A significant direct correlation was observed between left ventricular mass index (LVMI) and obesity markers [body mass index (BMI): r = 0.38, waist circumference (WC): r = 0.46, P < 0.04 for both]. Left ventricular hypertrophy, relative wall thickness and left atrial diameter were significantly related to BMI and WC. In contrast, office and ambulatory BP were unrelated to other variables, and differences in LVMI among different BP phenotypes were not significant. When partitioning the population by insulin resistance, LVMI, adjusted for confounders, was significantly greater in the insulin-resistant group.

CONCLUSIONS

In children and adolescents characterized by different body weight patterns, weight factors "per se" and the related insulin resistance state appear to represent the main determinants of LVMI and left ventricular hypertrophy, independently on BP values and BP phenotypes.

Lysophosphatidic Acid-Mediated Inflammation at the Heart of Heart Failure

PURPOSE OF REVIEW

The primary aim of this review is to provide an in-depth examination of the role bioactive lipids-namely lysophosphatidic acid (LPA) and ceramides-play in inflammation-mediated cardiac remodeling during heart failure. With the global prevalence of heart failure on the rise, it is critical to understand the underlying molecular mechanisms contributing to its pathogenesis. Traditional studies have emphasized factors such as oxidative stress and neurohormonal activation, but emerging research has shed light on bioactive lipids as central mediators in heart failure pathology. By elucidating these intricacies, this review aims to: Bridge the gap between basic research and clinical practice by highlighting clinically relevant pathways contributing to the pathogenesis and prognosis of heart failure. Provide a foundation for the development of targeted therapies that could mitigate the effects of LPA and ceramides on heart failure. Serve as a comprehensive resource for clinicians and researchers interested in the molecular biology of heart failure, aiding in better diagnostic and therapeutic decisions.

RECENT FINDINGS

Recent findings have shed light on the central role of bioactive lipids, specifically lysophosphatidic acid (LPA) and ceramides, in heart failure pathology. Traditional studies have emphasized factors such as hypoxia-mediated cardiomyocyte loss and neurohormonal activation in the development of heart failure. Emerging research has elucidated the intricacies of bioactive lipid-mediated inflammation in cardiac remodeling and the development of heart failure. Studies have shown that LPA and ceramides contribute to the pathogenesis of heart failure by promoting inflammation, fibrosis, and apoptosis in cardiac cells. Additionally, recent studies have identified potential targeted therapies that could mitigate the effects of bioactive lipids on heart failure, including LPA receptor antagonists and ceramide synthase inhibitors. These recent findings provide a promising avenue for the development of targeted therapies that could improve the diagnosis and treatment of heart failure. In this review, we highlight the pivotal role of inflammation induced by bioactive lipid signaling and its influence on the pathogenesis of heart failure. By critically assessing the existing literature, we provide a comprehensive resource for clinicians and researchers interested in the molecular mechanisms of heart failure. Our review aims to bridge the gap between basic research and clinical practice by providing actionable insights and a foundation for the development of targeted therapies that could mitigate the effects of bioactive lipids on heart failure. We hope that this review will aid in better diagnostic and therapeutic decisions, further advancing our collective understanding and management of heart failure.

Phenylacetyl glutamine (PAGln) enhances cardiomyocyte death after myocardial infarction through β1 adrenergic receptor

This study aims to explore the roles of phenylacetyl glutamine (PAGln) on myocardial infarction (MI) pathogenesis. Here, using targeted metabolomics analysis, it was found that the plasma metabolite PAGln was upregulated in coronary artery disease (CAD) patients and MI mice and could be an independent risk factor for CAD. In vivo and in vitro functional experiments revealed that PAGln pretreatment enhanced MI-induced myocardial injury and cardiac fibrosis, as evident by the increased infarct size, cardiomyocyte death, and the upregulated expression of cardiac fibrosis markers (Col1a1 and α-SMA). Combined with RNA-sequencing analysis and G protein-coupled receptor (GPCR) inhibitor, we found that the GPCR signaling activation is essential for PAGln-mediated effects on cardiomyocyte death. Furthermore, drug affinity responsive target stability and cellular thermal shift assay demonstrated that PAGln could interact with β1-adrenergic receptor (AR). Moreover, β1-AR blocker treatment indeed extended the cardiac remodeling after PAGln-enhanced MI. These results suggest that PAGln might be a potential therapeutic target for extending the cardiac remodeling window in MI patients that signals via β1-AR.

Left ventricular remodeling and long-term outcomes of aortic stenosis patients receiving 19 mm Mosaic

Mosaic valve shows higher pressure gradient after aortic valve replacement compared to other same size labeled prostheses in postoperative echocardiogram. The purpose of this study was to evaluate the mid-term echocardiogram findings and long-term clinical outcomes of patients receiving a 19 mm Mosaic. Forty-six aortic stenosis patients receiving 19 mm Mosaic and 112 patients receiving either 19 mm Magna or Inspiris, who underwent mid-term follow-up echocardiogram were included in the study. Mid-term hemodynamic measurements evaluated by trans-thoracic echocardiogram and long-term outcomes were compared. Patients receiving Mosaic were significantly older (Mosaic: 76 ± 5.1 years vs. Magna/Inspiris: 74 ± 5.5 years, p = 0.046) and had smaller body surface area (Mosaic: 1.40 ± 0.114m2 vs. Magna/Inspiris: 1.48 ± 0.143m2, p < 0.001). There were no significant differences in comorbidities and medications. Post-operative echocardiogram performed at 1 week after the surgery showed higher maximum pressure gradient in patients receiving Mosaic (Mosaic: 38 ± 13.5 mmHg vs. Magna/Inspiris: 31 ± 10.7 mmHg, p = 0.002). Furthermore, mid-term echocardiogram follow-up performed at median duration of 53 ± 14.9 months after the surgery continuously showed higher maximum pressure gradient in patients receiving Mosaic (Mosaic: 45 ± 15.6 mmHg vs. Magna/Inspiris: 32 ± 13.0 mmHg, p < 0.001). However, there were no significant difference in changes in left ventricular mass from baseline in both groups. Kaplan-Meyer curve also showed no difference in long-term mortality and major adverse cardiac and cerebrovascular event between the two groups. Although the pressure gradient across the valve evaluated by echocardiogram was higher in 19 mm Mosaic compared to 19 mm Magna/Inspiris, there were no significant differences in left ventricular remodeling and long-term outcomes between the two groups.

Contrast-enhanced cardiac MRI is superior to non-contrast mapping to predict left ventricular remodeling at 6 months after acute myocardial infarction

OBJECTIVES

Parametric mapping constitutes a novel cardiac magnetic resonance (CMR) technique enabling quantitative assessment of pathologic alterations of left ventricular (LV) myocardium. This study aimed to investigate the clinical utility of mapping techniques with and without contrast agent compared to standard CMR to predict adverse LV remodeling following acute myocardial infarction (AMI).

MATERIALS AND METHODS

A post hoc analysis was performed on sixty-four consecutively enrolled patients (57 ± 12 years, 54 men) with first-time reperfused AMI. Baseline CMR was obtained at 8 ± 5 days post-AMI, and follow-up CMR at 6 ± 1.4 months. T1/T2 mapping, T2-weighted, and late gadolinium enhancement (LGE) acquisitions were performed at baseline and cine imaging was used to determine adverse LV remodeling, defined as end-diastolic volume increase by 20% at 6 months.

RESULTS

A total of 11 (17%) patients developed adverse LV remodeling. At baseline, patients with LV remodeling showed larger edema (30 ± 11 vs. 22 ± 10%LV; p < 0.05), infarct size (24 ± 11 vs. 14 ± 8%LV; p < 0.001), extracellular volume (ECVinfarct; 63 ± 12 vs. 47 ± 11%; p < 0.001), and native T2infarct (95 ± 16 vs. 78 ± 17 ms; p < 0.01). ECVinfarct and infarct size by LGE were the best predictors of LV remodeling with areas under the curve (AUCs) of 0.843 and 0.789, respectively (all p < 0.01). Native T1infarct had the lowest AUC of 0.549 (p = 0.668) and was inferior to edema size by T2-weighted imaging (AUC = 0.720; p < 0.05) and native T2infarct (AUC = 0.766; p < 0.01).

CONCLUSION

In this study, ECVinfarct and infarct size by LGE were the best predictors for the development of LV remodeling within 6 months after AMI, with a better discriminative performance than non-contrast mapping CMR.

CLINICAL RELEVANCE STATEMENT

This study demonstrates the predictive value of contrast-enhanced and non-contrast as well as conventional and novel CMR techniques for the development of LV remodeling following AMI, which might help define precise CMR endpoints in experimental and clinical myocardial infarction trials.

KEY POINTS

• Multiparametric CMR provides insights into left ventricular remodeling at 6 months following an acute myocardial infarction. • Extracellular volume fraction and infarct size are the best predictors for adverse left ventricular remodeling. • Contrast-enhanced T1 mapping has a better predictive performance than non-contrast standard CMR and T1/T2 mapping.

Infertility and Subclinical Antecedents of Heart Failure With Preserved Ejection Fraction in the Framingham Heart Study

BACKGROUND

Infertility has been shown to be associated with a greater risk of incident heart failure with preserved ejection fraction. We studied the association of infertility with subclinical markers of heart failure with preserved ejection fraction, including echocardiographic signs of cardiac remodeling and cardiac biomarkers.

METHODS AND RESULTS

A history of infertility was ascertained in 2002 women enrolled in the Framingham Heart Study. We examined the association of infertility with echocardiographic measures and cardiac biomarkers with multivariable-adjusted linear regression models. Among 2002 women (mean age 40.84 ± 9.71 years), 285 (14%) reported a history of infertility. Infertility was associated with a greater E/e' ratio (β = 0.120, standard error 0.057, P = .04), even after adjustment for common confounders. Infertility was not associated with other echocardiographic measures or cardiac biomarkers.

CONCLUSIONS

Infertility was associated with a greater E/e' ratio, a marker of diastolic dysfunction that may signal earlier subclinical cardiac remodeling in women with infertility.

Restrictive annuloplasty on remodeling and survival in patients with end-stage ischemic cardiomyopathy

OBJECTIVES

To elucidate the influence of concomitant restrictive mitral annuloplasty (RMA) on postoperative left ventricular (LV) reverse remodeling and survival in patients with ischemic cardiomyopathy undergoing coronary artery bypass grafting (CABG).

METHODS

This study comprised 157 patients with ischemic cardiomyopathy (LV ejection fraction ≤40%) who underwent CABG and completed echocardiographic examination at 1 year after surgery, with 84 (54%) undergoing concomitant RMA for clinically relevant ischemic mitral regurgitation. The primary end point was postoperative reduction in LV end-systolic volume index (LVESVI). The secondary end point was overall survival. Median follow-up was 5.1 years.

RESULTS

At baseline, patients who underwent CABG with RMA had a larger LVESVI (83 ± 23 vs 75 ± 24 mm; P = .046). One-year postoperatively, CABG with RMA reduced the LVESVI more than did CABG alone (37% vs 21% from baseline; P < .001), yielding nearly identical postoperative LVESVI (53 ± 27 vs 61 ± 26 mm; P = .065). In multivariable logistic regression analysis, concomitant RMA was associated with significant LV reverse remodeling (odds ratio, 2.79; 95% CI, 1.34-5.78; P = .006). The prevalence in moderate or severe mitral regurgitation was not different between the groups (7% vs 10%; P = .58). Survival rates were similar between the groups (5 years, 78% vs 83%; P = .35).

CONCLUSIONS

In patients with ischemic cardiomyopathy undergoing CABG, concomitant RMA was associated with significant reduction in LVESVI. The influence of LV reverse remodeling on survival remains undetermined.

NAD in pathological cardiac remodeling: Metabolic regulation and beyond

Nicotinamide adenine dinucleotide (NAD) coenzymes are carriers of high energy electrons in metabolism and also play critical roles in numerous signaling pathways. NAD metabolism is decreased in various cardiovascular diseases. Importantly, stimulation of NAD biosynthesis protects against heart disease under different pathological conditions. In this review, we describe pathways for both generation and catabolism of NAD coenzymes and the respective changes of these pathways in the heart under cardiac diseases, including pressure overload, myocardial infarction, cardiometabolic disease, cancer treatment cardiotoxicity, and heart failure. We next provide an update on the strategies and treatments to increase NAD levels, such as supplementation of NAD precursors, in the heart that prevent or reverse cardiomyopathy. We also introduce the approaches to manipulate NAD consumption enzymes to ameliorate cardiac disease. Finally, we discuss the mechanisms associated with improvements in cardiac function by NAD coenzymes, differentiating between mitochondria-dependent effects and those independent of mitochondrial metabolism.

Effects evaluation of different exercises on subclinical left ventricular dysfunction in obese rats by speckle-tracking echocardiography

OBJECTIVE

To identify subclinical left ventricle dysfunction (LVD) in obese rats by speckle-tracking echocardiography, and to evaluate the effects of 12-week Moderate-Intensity Continuous Training (MICT) or High-Intensity Interval Training (HIIT) on LV geometry, histology and function in obese rats.

METHODS

Eighteen male standard or obese Sprague-Dawley rats were randomly divided into the Control group, the MICT group, and the HIIT group. Exercise interventions were conducted for 12 weeks, with equal total load and increased intensity gradient. Using dual-energy X-ray, two-dimensional speckle-tracking echocardiography, pulse Doppler, and HE staining to evalucate body shape, LV morphology, structure, and myocardial mechanics function.

RESULTS

(1) Both MICT and HIIT have good weight loss shaping effect. (2) The LV of obese rats underwent pathological remodeling, with decreased longitudinal contractility and synchrony, and increased circumferential contractility and synchrony. (3) Exercise can inhibit LV pathological remodeling, improve myocardial mechanical function. HIIT is superior to MICT. (4) The global longitudinal strain of obese rats in the HIIT group showed a significant correlation with Fat% and Lean%.

CONCLUSION

Obesity can induce LV pathological remodeling and subclinical dysfunction. Compared with MICT, 12-week HIIT can effectively inhibit the pathological remodeling of LV and promote the benign development of myocardial mechanical function in obese rats.

Amphiregulin improves ventricular remodeling after myocardial infarction by modulating autophagy and apoptosis

Myocardial infarction (MI) is defined as sudden ischemic death of myocardial tissue. Amphiregulin (Areg) regulates cell survival and is crucial for the healing of tissues after damage. However, the functions and mechanisms of Areg after MI remain unclear. Here, we aimed to investigate Areg's impact on myocardial remodeling. Mice model of MI was constructed and Areg-/- mice were used. Expression of Areg was analyzed using western blotting, RT-qPCR, flow cytometry, and immunofluorescence staining. Echocardiographic analysis, Masson's trichrome, and triphenyltetrazolium chloride staining were used to assess cardiac function and structure. RNA sequencing was used for unbiased analysis. Apoptosis and autophagy were determined by western blotting, TUNEL staining, electron microscopy, and mRFP-GFP-LC3 lentivirus. Lysosomal acidity was determined by Lysotracker staining. Areg was elevated in the infarct border zone after MI. It was mostly secreted by macrophages. Areg deficiency aggravated adverse ventricular remodeling, as reflected by worsening cardiac function, a lower survival rate, increased scar size, and interstitial fibrosis. RNA sequencing analyses showed that Areg related to the epidermal growth factor receptor (EGFR), phosphoinositide 3-kinase/protein kinase B (PI3K-Akt), mammalian target of rapamycin (mTOR) signaling pathways, V-ATPase and lysosome pathways. Mechanistically, Areg exerts beneficial effects via increasing lysosomal acidity to promote autophagosome clearance, and activating the EGFR/PI3K/Akt/mTOR signaling pathway, subsequently inhibiting excessive autophagosome formation and apoptosis in cardiomyocytes. This study provides a novel evidence for the role of Areg in inhibiting ventricular remodeling after MI by regulating autophagy and apoptosis and identifies Areg as a potential therapeutic target in ventricular remodeling after MI.

B cell subsets contribute to myocardial protection by inducing neutrophil apoptosis after ischemia and reperfusion

A robust, sterile inflammation underlies myocardial ischemia and reperfusion injury (MIRI). Several subsets of B cells possess the immunoregulatory capacity that limits tissue damage, yet the role of B cells in MIRI remains elusive. Here, we sought to elucidate the contribution of B cells to MIRI by transient ligation of the left anterior descending coronary artery in B cell-depleted or -deficient mice. Following ischemia and reperfusion (I/R), regulatory B cells are rapidly recruited to the heart. B cell-depleted or -deficient mice exhibited exacerbated tissue damage, adverse cardiac remodeling, and an augmented inflammatory response after I/R. Rescue and chimeric experiments indicated that the cardioprotective effect of B cells was not solely dependent on IL-10. Coculture experiments demonstrated that B cells induced neutrophil apoptosis through contact-dependent interactions, subsequently promoting reparative macrophage polarization by facilitating the phagocytosis of neutrophils by macrophages. The in vivo cardioprotective effect of B cells was undetectable in the absence of neutrophils after I/R. Mechanistically, ligand-receptor imputation identified FCER2A as a potential mediator of interactions between B cells and neutrophils. Blocking FCER2A on B cells resulted in a reduction in the percentage of apoptotic neutrophils, contributing to the deterioration of cardiac remodeling. Our findings unveil a potential cardioprotective role of B cells in MIRI through mechanisms involving FCER2A, neutrophils, and macrophages.

Left bundle branch pacing better preserves ventricular mechanical synchrony than right ventricular pacing: a two-centre study

AIMS

Left bundle branch pacing (LBBP) has been shown to better maintain electrical synchrony compared with right ventricular pacing (RVP), but little is known about its impact on mechanical synchrony. This study investigates whether LBBP better preserves left ventricular (LV) mechanical synchronicity and function compared with RVP.

METHODS AND RESULTS

Sixty patients with pacing indication for bradycardia were included: LBBP (n = 31) and RVP (n = 29). Echocardiography was performed before and shortly after pacemaker implantation and at 1-year follow-up. The lateral wall-septal wall (LW-SW) work difference was used as a measure of mechanical dyssynchrony. Septal flash, apical rocking, and septal strain patterns were also assessed. At baseline, LW-SW work difference was small and similar in two groups. SW was markedly decreased, while LW work remained mostly unchanged in RVP, resulting in a larger LW-SW work difference compared with LBBP (1253 ± 687 mmHg·% vs. 439 ± 408 mmHg·%, P < 0.01) at last follow-up. In addition, RVP more often induced septal flash or apical rocking and resulted in more advanced strain patterns compared with LBBP. At 1 year follow-up, LV ejection fraction (EF) and global longitudinal strain (GLS) were more decreased in RVP compared with LBBP (ΔLVEF: -7.4 ± 7.0% vs. 0.3 ± 4.1%; ΔLVGLS: -4.8 ± 4.0% vs. -1.4 ± 2.5%, both P < 0.01). In addition, ΔLW-SW work difference was independently correlated with LV adverse remodelling (r = 0.42, P < 0.01) and LV dysfunction (ΔLVEF: r = -0.61, P < 0.01 and ΔLVGLS: r = -0.38, P = 0.02).

CONCLUSION

LBBP causes less LV mechanical dyssynchrony than RVP as it preserves a more physiologic electrical conduction. As a consequence, LBBP appears to preserve LV function better than RVP.

[Index of microcirculatory resistance is associated with left ventricular remodeling in patients with acute anterior ST-segment elevation myocardial infarction undergoing emergency primary percutaneous coronary intervention]

OBJECTIVE

To evaluate whether index of microcirculatory resistance (IMR) is associated with left ventricular (LV) remodeling in acute anterior ST elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PPCI).

METHODS

This was a single-center retrospective cohort study. The patients with first anterior STEMI who received PPCI from January 2014 to August 2017 in Peking University Third Hospital was enrolled. After PPCI, IMR was measured immediately by using pressure/temperature guidewire. The success rate of IMR measurement was 100%. Also we collected some related clinical data from the medical records and laboratory results. Infarct size [assessed as creatine kinase (CK) peak], echocardiography at baseline and 1 year follow-up were assessed. LV adverse remodeling (LVAR) was defined as ≥20% increase in LV end-diastolic volume (LVEDV).

RESULTS

A total of forty-three patients were enrolled, with an average age of (58.7±12.4) years.The patients were divided into two groups as IMR ≤25 and IMR>25 by normal values recommended by previous literature. Compared with IMR ≤25 group, IMR>25 group had a higher percentage of initial thrombolysis in myocardial infraction (TIMI) grade 0 (95.7% vs. 65.0%, P=0.029), higher serum CK peak value [4 090 (383, 15 833)vs. 1 580 (396, 5 583), P=0.004]. The IMR>25 group suffered higher rates of ventricular aneurysm (30.4% vs. 5.0%, P=0.021). There was no difference in LVEDV [(111.0±18.8) mL vs. (115.0±23.6) mL, P=0.503] between the two groups 1 day after MI, but after 1 year, LVEDV in IMR>25 group was significantly higher than in IMR≤25 group [(141.5±33.7) mL vs. (115.9±27.9) mL, P=0.018]. The incidence of LVAR was more significant in IMR>25 group (47.4% vs. 11.8%, P=0.024). Binary Logistics regression showed that IMR [B=0.079, exp(B) (95%CI)=1.082 (1.018－1.149), P=0.011] and serum triglyceride level [B=1.610, exp(B) (95%CI)=5.005 (1.380－18.152), P=0.014] were the predictors of LVAR 1 year after MI. IMR had a good predictive value for LVAR 1 year after MI [area under the curve (AUC)=0.749, P=0.019], IMR>29 was a good cutoff value with sensitivity 81.8% and specificity 68.0%.

CONCLUSION

Our study elaborates that immediate measurement of IMR after PPCI in patients with STEMI can reflect the microvascular function.And IMR could be used as a quantitative biomarker to predict LVAR after STEMI.

Strength training improves heart function, collagen and strength in rats with heart failure

BACKGROUND/OBJECTIVES

Myocardial infarction (MI) frequently leads to cardiac remodeling and failure with impaired life quality, playing an important role in cardiovascular deaths. Although physical exercise is a well-recognized effective non-pharmacological therapy for cardiovascular diseases, the effects of strength training (ST) on the structural and functional aspects of cardiac remodeling need to be further documented. In this study, we aimed to investigate the role of a linear block ST protocol in the rat model of MI.

METHODS AND RESULTS

After 6 weeks of MI induction or sham surgery, male adult rats performed ST for the following 12 weeks. The ladder-based ST program was organized in three mesocycles of 4 weeks, with one load increment for each block according to the maximal carrying load test. After 12 weeks, the infarcted-trained rats exhibited an increase in performance, associated with reduced cardiac hypertrophy and pulmonary congestion compared with the untrained group. Despite not changing MI size, the ST program partially prevented cardiac dilatation and ventricular dysfunction assessed by echocardiography and hemodynamics, and interstitial fibrosis evaluated by histology. In addition, isolated cardiac muscles from infarcted-trained rats had improved contractility parameters in a steady state, and in response to calcium or stimuli pauses.

CONCLUSIONS

The ST in infarcted rats increased the capacity to carry mass, associated with attenuation of cardiac remodeling and pulmonary congestion with improving cardiac function that could be attributed, at least in part, to the improvement of myocardial contractility.

Impact of thrombus aspiration on left ventricular remodeling and function in patients with ST-segment elevation myocardial infarction: A meta-analysis of randomized controlled trials

BACKGROUND

Routine thrombus aspiration (TA) does not improve clinical outcomes in patients with ST-segment-elevation myocardial infarction (STEMI), although data from meta-analyses suggest that patients with high thrombus burden may benefit from it. The impact of TA on left ventricular (LV) functional recovery and remodeling after STEMI remains controversial. We aimed to pool data from randomized controlled trials (RCTs) on the impact of TA on LV function and remodeling after primary percutaneous coronary intervention (pPCI).

METHODS

PubMed and CENTRAL databases were scanned for eligible studies. Primary outcome measures were: LV ejection fraction (LVEF), LV end diastolic volume (LVEDV), LV end systolic volume (LVESV) and wall motion score index (WMSI). A primary pre-specified subgroup analysis was performed comparing manual TA with mechanical TA.

RESULTS

A total of 28 studies enrolling 4990 patients were included. WMSI was lower in TA group than in control (mean difference [MD] -0.11, 95% confidence interval [CI] -0.19 to -0.03). A greater LVEF (MD 1.91, 95% CI 0.76 to 3) and a smaller LVESV (MD -6.19, 95% CI -8.7 to -3.6) were observed in manual TA group compared to control. Meta regressions including patients with left anterior descending artery (LAD) involvement showed an association between TA use and the reduction of both LVEDV and LVESV (z = -2.13, p = 0.03; z = -3.7, p < 0.01) and the improvement in myocardial salvage index (z = 2.04, p = 0.04).

CONCLUSION

TA is associated with improved LV function. TA technique, total ischemic time and LAD involvement appears to influence TA benefit on post-infarction LV remodeling.

Cardiac Remodeling After Hypertensive Pregnancy Following Physician-Optimized Blood Pressure Self-Management: The POP-HT Randomized Clinical Trial Imaging Substudy

BACKGROUND

Hypertensive pregnancy disorders are associated with adverse cardiac remodeling, which can fail to reverse in the postpartum period in some women. The Physician-Optimized Postpartum Hypertension Treatment trial demonstrated that improved blood pressure control while the cardiovascular system recovers postpartum associates with persistently reduced blood pressure. We now report the effect on cardiac remodeling.

METHODS

In this prospective, randomized, open-label, blinded end point trial, in a single UK hospital, 220 women were randomly assigned 1:1 to self-monitoring with research physician-optimized antihypertensive titration or usual postnatal care from a primary care physician and midwife. Participants were 18 years of age or older, with preeclampsia or gestational hypertension, requiring antihypertensives on hospital discharge postnatally. Prespecified secondary cardiac imaging outcomes were recorded by echocardiography around delivery, and again at blood pressure primary outcome assessment, around 9 months postpartum, when cardiovascular magnetic resonance was also performed.

RESULTS

A total of 187 women (101 intervention; 86 usual care) underwent echocardiography at baseline and follow-up, at a mean 258±14.6 days postpartum, of which 174 (93 intervention; 81 usual care) also had cardiovascular magnetic resonance at follow-up. Relative wall thickness by echocardiography was 0.06 (95% CI, 0.07-0.05; P<0.001) lower in the intervention group between baseline and follow-up, and cardiovascular magnetic resonance at follow-up demonstrated a lower left ventricular mass (-6.37 g/m2; 95% CI, -7.99 to -4.74; P<0.001), end-diastolic volume (-3.87 mL/m2; 95% CI, -6.77 to -0.98; P=0.009), and end-systolic volume (-3.25 mL/m2; 95% CI, 4.87 to -1.63; P<0.001) and higher left and right ventricular ejection fraction by 2.6% (95% CI, 1.3-3.9; P<0.001) and 2.8% (95% CI, 1.4-4.1; P<0.001), respectively. Echocardiography-assessed left ventricular diastolic function demonstrated a mean difference in average E/E' of 0.52 (95% CI, -0.97 to -0.07; P=0.024) and a reduction in left atrial volumes of -4.33 mL/m2 (95% CI, -5.52 to -3.21; P<0.001) between baseline and follow-up when adjusted for baseline differences in measures.

CONCLUSIONS

Short-term postnatal optimization of blood pressure control after hypertensive pregnancy, through self-monitoring and physician-guided antihypertensive titration, associates with long-term changes in cardiovascular structure and function, in a pattern associated with more favorable cardiovascular outcomes.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04273854.

Roxadustat Versus Erythropoietin: The Comparison of Efficacy in Reversing Ventricular Remodeling in Dialysis Patients with Anaemia

Background: Renal anaemia and left ventricular hypertrophy are the main complications of chronic kidney disease and are shared among dialysis patients. This retrospective study aimed to compare the efficacies of the hypoxia-inducible factor prolyl hydroxylase inhibitor roxadustat and recombinant human erythropoietin in reversing ventricular remodeling in dialysis patients with renal anaemia. Methods: A total of 204 participants underwent baseline examinations, including echocardiograms and laboratory tests, before being administered either treatment for at least 24 weeks from January 2018 to October 2021, after which follow-up examinations were conducted at 6 months. Propensity score matching based on key variables included age, gender, cardiovascular diseases, cardiovascular medications, dialysis course and the vascular access at baseline was performed to include populations with similar characteristics between groups. Results: In total, 136 patients were included with roxadustat or recombinant human erythropoietin. The left ventricular mass index after treatment with roxadustat and recombinant human erythropoietin both significantly decreased after 6 months, but there was no significant difference in the change in left ventricular mass index between the two groups. In addition, the left ventricular end-diastolic diameters and left ventricular wall thickness, systolic blood pressure, and diastolic blood pressure significantly decreased in the roxadustat group. Roxadustat and recombinant human erythropoietin also increased haemoglobin significantly, but there was no significant difference in the change in haemoglobin between the two groups. The results of multiple linear regression showed that the change in haemoglobin was independent factor affecting the improvement of left ventricular mass index. Conclusions: The increase of haemoglobin was associated with improving left ventricular hypertrophy in dialysis patients. However, the beneficial effects between roxadustat and recombinant human erythropoietin on left ventricular mass index did not show clear superiority or inferiority in six months.

Montelukast, an available and safe anti-asthmatic drug, prevents maladaptive remodelling and maintains cardiac functionality following myocardial infarction

Preclinical and clinical data indicate that the 5-lipoxygenase pathway becomes activated in cardiovascular diseases suggesting an important role of CysLTs in atherosclerosis and in its ischemic complications. This study aims to investigate the effects of montelukast, a CysLTR-1 antagonist, in a mouse model of myocardial infarction (MI). C57BL/6N female mice were subjected to coronary artery ligation and received montelukast (10 mg/kg/day, intraperitoneal) or vehicle. Montelukast exerted beneficial effects in the infarcted area, decreasing mRNA expression of inflammatory genes, such Il1β and Ccl2 (p < 0.05), at 48 h after MI, and reducing infarct size and preventing ischemic wall thinning (p < 0.05) at 4 weeks. Furthermore, montelukast counteracted maladaptive remodelling of whole heart. Indeed, montelukast reduced LV mass (p < 0.05) and remote wall thickening (p < 0.05), and improved cardiac pumping function, as evidenced by increased global ejection fraction (p < 0.01), and regional contractility in infarcted (p < 0.05) and in remote non-infarcted (p < 0.05) myocardium. Finally, montelukast prevented cardiomyocytes hypertrophy (p < 0.05) in remote myocardium, reducing the phosphorylation of GSK3β, a regulator of hypertrophic pathway (p < 0.05). Our data strongly demonstrate the ability of montelukast to contrast the MI-induced maladaptive conditions, thus sustaining cardiac contractility. The results provide evidences for montelukast "repurposing" in cardiovascular diseases and in particular in myocardial infarction.

Hypoxia Attenuates Pressure Overload-Induced Heart Failure

BACKGROUND

Alveolar hypoxia is protective in the context of cardiovascular and ischemic heart disease; however, the underlying mechanisms are incompletely understood. The present study sought to test the hypothesis that hypoxia is cardioprotective in left ventricular pressure overload (LVPO)-induced heart failure. We furthermore aimed to test that overlapping mechanisms promote cardiac recovery in heart failure patients following left ventricular assist device-mediated mechanical unloading and circulatory support.

METHODS AND RESULTS

We established a novel murine model of combined chronic alveolar hypoxia and LVPO following transverse aortic constriction (HxTAC). The HxTAC model is resistant to cardiac hypertrophy and the development of heart failure. The cardioprotective mechanisms identified in our HxTAC model include increased activation of HIF (hypoxia-inducible factor)-1α-mediated angiogenesis, attenuated induction of genes associated with pathological remodeling, and preserved metabolic gene expression as identified by RNA sequencing. Furthermore, LVPO decreased Tbx5 and increased Hsd11b1 mRNA expression under normoxic conditions, which was attenuated under hypoxic conditions and may induce additional hypoxia-mediated cardioprotective effects. Analysis of samples from patients with advanced heart failure that demonstrated left ventricular assist device-mediated myocardial recovery revealed a similar expression pattern for TBX5 and HSD11B1 as observed in HxTAC hearts.

CONCLUSIONS

Hypoxia attenuates LVPO-induced heart failure. Cardioprotective pathways identified in the HxTAC model might also contribute to cardiac recovery following left ventricular assist device support. These data highlight the potential of our novel HxTAC model to identify hypoxia-mediated cardioprotective mechanisms and therapeutic targets that attenuate LVPO-induced heart failure and mediate cardiac recovery following mechanical circulatory support.

High-Intensity Interval Training Is Associated With Improved 10-Year Survival by Mediating Left Ventricular Remodeling in Patients With Heart Failure With Reduced and Mid-Range Ejection Fraction

BACKGROUND

This study aimed to assess the left ventricular (LV) remodeling response and long-term survival after high-intensity interval training (HIIT) in patients with various heart failure (HF) phenotypes during a 10-year longitudinal follow-up.

METHODS AND RESULTS

Among 214 patients with HF receiving guideline-directed medical therapy, those who underwent an additional 36 sessions of aerobic exercise at alternating intensities of 80% and 40% peak oxygen consumption (V ̇ $$ \dot{\mathrm{V}} $$ O2peak) were considered HIIT participants (n=96). Patients who did not undergo HIIT were considered participants receiving guideline-directed medical therapy (n=118). Participants with LV ejection fraction (EF) <40%, ≥40% and <50%, and ≥50% were considered to have HF with reduced EF, HF with mid-range EF, and HF with preserved EF, respectively. V ̇ $$ \dot{\mathrm{V}} $$ O2peak, serial LV geometry, and time to death were recorded. In all included participants, 10-year survival was better (P=0.015) for participants who underwent HIIT (80.3%) than for participants receiving guideline-directed medical therapy (68.6%). An increased V ̇ $$ \dot{\mathrm{V}} $$ O2peak, decreased minute ventilation carbon dioxide production slope, and reduced LV end-diastolic diameter were protective factors against all-cause mortality. Regarding 138 patients with HF with reduced EF (P=0.044) and 36 patients with HF with mid-range EF (P=0.036), 10-year survival was better for participants who underwent HIIT than for participants on guideline-directed medical therapy. Causal mediation analysis showed a significant mediation path for LV end-diastolic diameter on the association between HIIT and 10-year mortality in all included patients with HF (P<0.001) and those with LV ejection fraction <50% (P=0.006). HIIT also had a significant direct association with 10-year mortality in patients with HF with LV ejection fraction <50% (P=0.027) but not in those with LV ejection fraction ≥50% (n=40).

CONCLUSIONS

Reversal of LV remodeling after HIIT could be a significant mediating factor for 10-year survival in patients with HF with reduced EF and those with HF with mid-range EF.

MicroRNA-30d and -483-3p for bi-ventricular remodelling and miR-126-3p for pulmonary hypertension in advanced heart failure

AIMS

MicroRNAs play a role in pathogenic mechanisms leading to heart failure. We measured a panel of 754 miRNAs in the myocardial tissue and in the serum of patients with heart failure with reduced ejection fraction due to dilatative idiopathic cardiomyopathy (DCM, N = 10) or ischaemic cardiomyopathy (N = 3), referred to left ventricular assist device implant. We aim to identify circulating miRNAs with high tissue co-expression, significantly associated to echocardiographic and haemodynamic measures.

METHODS AND RESULTS

We have measured a panel of 754 miRNAs in the myocardial tissue [left ventricular (LV) apex] and in the serum obtained at the same time in a well selected study population of end-stage heart failure with reduced ejection fraction due to either DCM or ischaemic cardiomyopathy, referred to continuous flow left ventricular assist device implant. We observed moderate agreement for miR-30d, miR-126-3p, and miR-483-3p. MiR-30d was correlated to LV systolic as well as diastolic volumes (r = 0.78, P = 0.001 and r = 0.80, P = 0.005, respectively), while miR-126-3p was associated to mPAP and PCWP (r = -0.79, P = 0.007 and r = -0.80, P = 0.005, respectively). Finally, serum miR-483-3p had an association with right ventricular end diastolic diameter (r = -0.73, P = 0.02) and central venous pressure (CVP) (r - 0.68 p 0.03).

CONCLUSIONS

In patients with DCM, few miRNAs are co-expressed in serum and tissue: They are related to LV remodelling (miR-30d), post-capillary pulmonary artery pressure (miR-126-3p), and right ventricular remodelling/filling pressures (miR-483-3p). Further studies are needed to confirm their role in diagnosis, prognosis or as therapeutic targets in heart failure with reduced ejection fraction.

The impact of phosphodiesterase-5 inhibition or angiotensin-converting enzyme inhibition on right and left ventricular remodeling in heart failure due to chronic volume overload

While phosphodiesterase-5 inhibition (PED5i) may prevent hypertrophy and failure in pressure-overloaded heart in an experimental model, the impact of PDE5i on volume-overload (VO)-induced hypertrophy is unknown. It is also unclear whether the hypertrophied right ventricle (RV) and left ventricle (LV) differ in their responsiveness to long-term PDE5i and if this therapy affects renal function. The goal of this study was to elucidate the effect of PDE5i treatment in VO due to aorto-caval fistula (ACF) and to compare PDE5i treatment with standard heart failure (HF) therapy with angiotensin-converting enzyme inhibitor (ACEi). ACF/sham procedure was performed on male HanSD rats aged 8 weeks. ACF animals were randomized for PDE5i sildenafil, ACEi trandolapril, or placebo treatments. After 20 weeks, RV and LV function (echocardiography, pressure-volume analysis), myocardial gene expression, and renal function were studied. Separate rat cohorts served for survival analysis. ACF led to biventricular eccentric hypertrophy (LV: +68%, RV: +145%), increased stroke work (LV: 3.6-fold, RV: 6.7-fold), and reduced load-independent systolic function (PRSW, LV: -54%, RV: -51%). Both ACF ventricles exhibited upregulation of the genes of myocardial stress and glucose metabolism. ACEi but not PDE5i attenuated pulmonary congestion, LV remodeling, albuminuria, and improved survival (median survival in ACF/ACEi was 41 weeks vs. 35 weeks in ACF/placebo, p = .02). PDE5i increased cyclic guanosine monophosphate levels in the lungs, but not in the RV, LV, or kidney. PDE5i did not improve survival rate and cardiac and renal function in ACF rats, in contrast to ACEi. VO-induced HF is not responsive to PDE5i therapy.

2,5-Dimethyl-celecoxib induces early termination of inflammatory responses by transient macrophage accumulation and inhibits the progression of cardiac remodeling in a mouse model of cryoinjury-induced myocardial infarction

In our previous study, we reported that 2, 5-dimethyl-celecoxib (DM-C), a derivative of celecoxib, prevents cardiac remodeling in different mouse models of heart failure, including myocardial infarction (MI). The inflammatory response after MI affects the progression of cardiac remodeling, wherein the immune cells, mainly macrophages, play crucial roles. Therefore, we evaluated the effect of DM-C on macrophages in a cryoinjury-induced myocardial infarction (CMI) mouse model. We observed that DM-C attenuated the deterioration of left ventricular ejection fraction and cardiac fibrosis 14 d after CMI. Gene expression of pro-inflammatory cytokines at the infarct site was reduced by DM-C treatment. Analysis of macrophage surface antigens revealed that DM-C induced transient accumulation of macrophages at the infarct site without affecting their polarization. In vitro experiments using peritoneal monocytes/macrophages revealed that DM-C did not directly increase the phagocytic ability of the macrophages but increased their number, thereby upregulating the clearance capacity. Moreover, DM-C rapidly excluded the cells expressing necrotic cell marker from the infarct site. These results suggested that DM-C enhanced the clearance capacity of macrophages by transiently increasing their number at the infarct site, and terminated the escape from the inflammatory phase earlier, thereby suppressing excessive cardiac remodeling and ameliorating cardiac dysfunction.

Left ventricular reverse remodeling following initiation of sacubitril/valsartan for heart failure with reduced ejection fraction and low blood pressure

Sacubitril/valsartan has become an important first-line drug for symptomatic heart failure (HF) patients, especially with left ventricular (LV) ejection fraction (LVEF) < 50%. However, the impact of sacubitril/valsartan on cardiovascular outcomes, especially LV reverse remodeling for such patients with low blood pressure, remains uncertain. We retrospectively studied 164 HF patients with LVEF < 50% who were treated with sacubitril/valsartan from two institutions. Echocardiography was performed before and 9.5 ± 5.1 months after initiation of maximum tolerated dose of sacubitril/valsartan. The maximum tolerated dose of sacubitril/valsartan was lower for the low blood pressure group (≤ 100 mmHg in systole) than for the non-low blood pressure group (> 100 mmHg in systole) (165 ± 106 mg vs. 238 ± 124 mg, P = 0.017). As expected, significant LV reverse remodeling was observed in the non-low blood pressure group after initiation of sacubitril/valsartan. It was noteworthy that significant LV reverse remodeling was also observed in the low blood pressure group after initiation of sacubitril/valsartan (LV end-diastolic volume: 177.3 ± 66.0 mL vs. 137.7 ± 56.1 mL, P < 0.001, LV end-systolic volume: 131.6 ± 60.3 mL vs. 94.6 ± 55.7 mL, P < 0.001, LVEF: 26.8 ± 10.3% vs. 33.8 ± 13.6%, P = 0.015). Relative changes in LV volumes and LVEF after initiation of sacubitril/valsartan were similar for the two groups. In conclusion, significant LV reverse remodeling occurred after initiation of sacubitril/valsartan, even in HF patients with LVEF < 50% and systolic blood pressure ≤ 100 mmHg.

Effects of Electronic Cigarette Vaping on Cardiac and Vascular Function, and Post-myocardial Infarction Remodeling in Rats

The effect of electronic cigarette (E-cig) vaping on cardiac and vascular function during the healing phase of myocardial infarction (MI), and post-MI remodeling was investigated. Sprague Dawley rats were subjected to left coronary artery ligation to induce MI. One week later, rats were randomized to receive either 12 weeks of exposure to purified air (n = 37) or E-cig vapor (15 mg/ml of nicotine) (n = 32). At 12 weeks, cardiac and vascular function, and post-MI remodeling were assessed. Baseline blood flow in the femoral artery did not differ between groups, but peak reperfusion blood flow was blunted in the E-cig group (1.59 ± 0.15 ml/min) vs. the air group (2.11 ± 0.18 ml/min; p = 0.034). Femoral artery diameter after reperfusion was narrower in the E-cig group (0.54 ± 0.02 mm) compared to the air group (0.60 ± 0.02 mm; p = 0.023). Postmortem left ventricular (LV) volumes were similar in the E-cig (0.69 ± 0.04 ml) and air groups (0.73 ± 0.04 ml; p = NS); and myocardial infarct expansion index did not differ between groups (1.4 ± 0.1 in E-cig group versus 1.3 ± 0.1 in air group; p = NS). LV fractional shortening by echo did not differ between groups at 12 weeks (E-cig at 29 ± 2% and air at 27 ± 1%; p = NS). Exposure to E-cig during the healing phase of MI was associated with altered vascular function with reduced femoral artery blood flow and diameter at reperfusion, but not with worsened LV dilation or worsened cardiac function.

Ferrostatin-1 Blunts Right Ventricular Hypertrophy and Dysfunction in Pulmonary Arterial Hypertension by Suppressing the HMOX1/GSH Signaling

Ferroptosis plays a critical role in pulmonary arterial hypertension (PAH)-induced right ventricular (RV) dysfunction, but key genes remain largely unclear. We here identified HMOX1 as an essential ferroptosis-related differentially expressed gene in PAH by bioinformatic analysis using FerrDb, GSE119754, and GSE3675 datasets, respectively. Notably, there were marked increases in HMOX1 and iron levels in RV of monocrotaline-induced PAH rats with reduced TAPSE levels. More importantly, treatment with ferrostatin-1 effectively attenuated RV hypertrophy, remodeling, myocardial fibrosis, and dysfunction in PAH rats. In cultured H9C2 cells and primary neonatal rat cardiomyocytes, pretreatment with ferrostatin-1 and knockdown HMOX1 by siRNA strikingly blunted hypoxia-induced promotion of lipid peroxidation, ferroptosis, and cardiomyocyte injury by potentiating glutathione (GSH) and nitric oxide signaling, respectively. In summary, ferrostatin-1 attenuates RV hypertrophy, fibrosis, and dysfunction in PAH by suppressing the HMOX1/GSH signaling. Targeting HMOX1 ferroptosis signaling functions as a potential therapeutic strategy for patients with PAH.

The effect of sodium-glucose cotransporter 2 inhibitors on left cardiac remodelling in heart failure with reduced ejection fraction: Systematic review and meta-analysis

AIMS

The therapeutic mechanism of sodium-glucose cotransporter 2 inhibitors (SGLT2i) on left cardiac remodelling in patients with heart failure with reduced ejection fraction (HFrEF) is not well-established. This study meta-analysed the impact of SGLT2i on left cardiac structure and function in patients with HFrEF.

METHODS AND RESULTS

Online databases were queried up to April 2023 for trials reporting indicators of left cardiac structure and function in patients with HFrEF treated with SGLT2i. Data from studies were pooled using a random-effects model to derive weighted mean differences (WMDs) and 95% confidence intervals (CIs). Six trials were included (n = 555). Compared with control, SGLT2i significantly improved left ventricular end-diastolic volume (LVEDV; WMD: -17.07 ml [-23.84, -10.31]; p < 0.001), LVEDV index (WMD: -5.62 ml/m2 [-10.28, -0.97]; p = 0.02), left ventricular end-systolic volume (LVESV; WMD: -15.63 ml [-26.15, -5.12]; p = 0.004), LVESV index (WMD: -6.90 ml/m2 [-10.68, -3.11]; p = 0.001), left ventricular ejection fraction (WMD: 2.71% [0.70, 4.72]; p = 0.008), and left atrial volume index (WMD: -2.19 ml/m2 [-4.26, -0.11]; p = 0.04) in patients with HFrEF. SGLT2i use was associated with a non-significant trend towards a reduction in left ventricular mass index (WMD: -6.25 g/m2 [-12.79, 0.28]; p = 0.06). No significant impact on left ventricular global longitudinal strain was noted (WMD: 0.21% [-0.25, 0.67]; p = 0.38).

CONCLUSIONS

Sodium-glucose cotransporter 2 inhibitors improve cardiac structure and function in patients with HFrEF.

The effects of daily dose of intense exercise on cardiac responses and atrial fibrillation

Atrial fibrillation (AF) is a supraventricular tachyarrhythmia that is strongly associated with cardiovascular (CV) disease and sedentary lifestyles. Despite the benefits of exercise on overall health, AF incidence in high-level endurance athletes rivals that of CV disease patients, suggesting a J-shaped relationship with AF. To investigate the dependence of AF vulnerability on exercise, we varied daily swim durations (120, 180 or 240 min day-1 ) in 7-week-old male CD1 mice. We assessed mice after performing equivalent amounts of cumulative work during swimming (i.e. ∼700 L O2  kg-1 ), as determined from O2 consumption rates (V ̇ O 2 ${\dot V_{{{\mathrm{O}}_2}}}$ ). The meanV ̇ O 2 ${\dot V_{{{\mathrm{O}}_2}}}$ during exercise increased progressively throughout the training period and was indistinguishable between the swim groups. Consistent with similar improvements in aerobic conditioning induced by swimming, skeletal muscle mitochondria content increased (P = 0.027) indistinguishably between exercise groups. Physiological ventricular remodelling, characterized by mild hypertrophy and left ventricular dilatation, was also similar between exercised mice without evidence of ventricular arrhythmia inducibility. By contrast, prolongation of daily swim durations caused progressive and vagal-dependent heart rate reductions (P = 0.008), as well as increased (P = 0.005) AF vulnerability. As expected, vagal inhibition prolonged (P = 0.013) atrial refractoriness, leading to reduced AF vulnerability, although still inducible in the 180 and 240 min swim groups. Accordingly, daily swim dose progressively increased atrial hypertrophy (P = 0.003), fibrosis (P < 0.001) and macrophage accumulation (P = 0.006) without differentially affecting the ventricular tissue properties. Thus, increasing daily exercise duration drives progressively adverse atrial-specific remodelling and vagal-dependent AF vulnerability despite robust and beneficial aerobic conditioning and physiological remodelling of ventricles and skeletal muscle. KEY POINTS: Previous studies have suggested that a J-shaped dose-response relationship exists between physical activity and cardiovascular health outcomes, with moderate exercise providing protection against many cardiovascular disease conditions, whereas chronic endurance exercise can promote atrial fibrillation (AF). We found that AF vulnerability increased alongside elevated atrial hypertrophy, fibrosis and inflammation as daily swim exercise durations in mice were prolonged (i.e. ≥180 min day-1 for 6 weeks). The MET-h week-1 (based on O2  measurements during swimming) needed to induce increased AF vulnerability mirrored the levels linked to AF in athletes. These adverse atria effects associated with excessive daily exercise occurred despite improved aerobic conditioning, skeletal muscle adaptation and physiological ventricular remodelling. We suggest that atrial-specific changes observed with exercise arise from excessive elevations in venous filling pressures during prolonged exercise bouts, which we argue has implications for all AF patients because elevated atrial pressures occur in most cardiovascular disease conditions as well as ageing which are linked to AF.

Left ventricular concentric hypertrophy with cardiac magnetic resonance imaging improves risk stratification in patients with Duchenne muscular dystrophy: a prospective cohort study

BACKGROUND

The development of left ventricular (LV) remodeling has been associated with an increased cardiovascular risk and cardiogenic death, and different patterns of remodeling result in varying levels of prognosis.

OBJECTIVE

To investigate the association between different patterns of LV remodeling and clinical outcomes in the preclinical stage of patients with Duchenne muscular dystrophy (DMD).

MATERIALS AND METHODS

A total of 148 patients with DMD and 43 sex- and age-matched healthy participants were enrolled. We used the four-quadrant analysis method to investigate LV remodeling based on cardiac magnetic resonance (MR) imaging. Kaplan-Meier curves were generated to illustrate the event-free survival probability stratified by the LV remodeling pattern. Cox regression models were constructed and compared to evaluate the incremental predictive value of the LV remodeling pattern.

RESULTS

During the median follow-up period of 2.2 years, all-cause death, cardiomyopathy, and ventricular arrhythmia occurred in 5, 35, and 7 patients, respectively. LV concentric hypertrophy (hazard ratio 2.91, 95% confidence interval 1.47-5.75, P=0.002) was an independent predictor of composite endpoint events. Compared to the model without LV concentric hypertrophy, the model with LV concentric hypertrophy had significant incremental predictive value (chi-square value 33.5 vs. 25.2, P=0.004).

CONCLUSION

Age and late gadolinium enhancement positivity were positively correlated with clinical outcomes according to the prediction models. LV concentric hypertrophy was also an independent predictor for risk stratification and provided incremental value for predicting clinical outcomes in the preclinical stage of patients with DMD.

Association of 20-Year Longitudinal Depressive Symptoms With Left Ventricular Geometry Outcomes in the Coronary Artery Risk Development in Young Adults Study: A Role for Androgens?

OBJECTIVE

Depression is a risk factor for coronary heart disease and left ventricular hypertrophy (LVH) is a potent predictor of coronary heart disease events. Whether depression is associated with LVH has received limited investigation. This study assessed cross-sectional and 20-year longitudinal associations of depressive symptoms with LVH outcomes after accounting for important known confounders.

METHODS

From 5115 participants enrolled in 1985-1986 in the Coronary Artery Risk Development in Young Adults Study, 2533 had serial measures of depressive symptoms and subsequent echocardiography to measure normal LV geometry, concentric remodeling, and LVH. The primary exposure variable was trajectories of the Center for Epidemiologic Studies Depression (CES-D) scale score from 1990-1991 to 2010-2011. Multivariable polytomous logistic regression was used to assess associations of trajectories with a composite LV geometry outcome created using echocardiogram data measured in 2010-2011 and 2015-2016. Sex-specific conflicting results led to exploratory models that examined potential importance of testosterone and sex hormone-binding globulin.

RESULTS

Overall CES-D and Somatic subscale trajectories had significant associations with LVH for female participants only. Odds ratios for the subthreshold (mean CES-D ≈ 14) and stable (mean CES-D ≈ 19) groups were 1.49 (95% confidence interval = 1.05-2.13) and 1.88 (95% confidence interval = 1.16-3.04), respectively. For female participants, sex hormone-binding globulin was inversely associated with LVH, and for male participants, bioavailable testosterone was positively associated with concentric geometry.

CONCLUSIONS

Findings from cross-sectional and longitudinal regression models for female participants, but not male ones, and particularly for Somatic subscale trajectories suggested a plausible link among depression, androgens, and LVH. The role of androgens to the depression-LVH relation requires additional investigation in future studies.

Left ventricular remodeling in twin pregnancy, noninvasively assessed using hemodynamic forces and pressure-volume relation analysis: prospective, cohort study

This study was designed to prospectively investigate the pattern of intraventricular hemodynamic forces (HDFs) associated with left ventricular (LV) function and remodeling in women with uncomplicated twin pregnancy. Transthoracic echocardiography was performed on 35 women (aged 35.9 ± 4.7-yr old) during gestation (T1, <14 wk; T2, 14-27 wk; T3, >28 wk) and 6-7 mo after delivery (T0). LV HDFs were computed from echocardiography long-axis data sets using a novel technique based on endocardial boundary tracking, both in apex-base (A-B) and latero-septal (L-S) directions. HDF distribution was evaluated by L-S over A-B HDF ratio (L-S:A-B HDF ratio). At T1, L-S:A-B HDF ratio was higher than in T0 (P < 0.05) indicating HDF misalignment. At T2, a slight impairment of cardiac function was then recorded with a reduction of global longitudinal strain (GLS) and left ventricular end-systolic elastance (Ees) at pressure-volume relationship analysis versus T1 (both P < 0.05). Finally, at T3, when HDF misalignment and LV contractility reduction (GLS and Ees) were all restored, a rightward shift of the end-diastolic pressure-volume relationship (EDPVR) with an increase of ventricular capacitance was documented. In twin pregnancy, HDF misalignment in the first trimester precedes the slight temporary decrease in left ventricular systolic function in the second trimester; at the third trimester, a rightward shift of the EDPVR was associated with a realignment of HDF and normalization of ventricular contractility indexes. These coordinated changes that occur in the maternal heart during twin pregnancy suggest the role of HDFs in cardiac remodeling.NEW & NOTEWORTHY These changes indicate that 1) the misalignment of hemodynamic forces (HDFs) precedes a mild reduction in systolic function in twin pregnancy and 2) the positive left ventricular (LV) response to hemodynamic stress is mainly due to an improved diastolic function with enhanced LV cavity compliance.

Cardiovascular Effects of Chronic Hormone Therapy: Study on Olympic Female Athletes

Female physiology is regulated after puberty by the menstrual cycle, whose hormonal fluctuations create a multitude of effects on several systems, including the cardiovascular one. The use of hormone therapy (HT) is quite common in female athletes, and data on cardiovascular effects in this population are lacking. We sought to investigate the effects of HT in highly trained athletes to assess any difference associated with HT on cardiac remodeling, exercise capacity, and clinical correlates. We studied 380 female elite athletes (mean age 25.5 ± 4.8) competing in endurance and mixed sports; 67 athletes (18%) were in chronic HT therapy. All athletes underwent baseline electrocardiography, exercise electrocardiography stress test, transthoracic echocardiogram, and complete blood tests, including lipid profile and inflammation indexes. The echocardiographic study showed a characteristic left ventricular (LV) remodeling, defined by lower LV mass index (86.2 vs 92.5 g/m2, p <0.006), end-diastolic LV diameter (28.3 vs 29.4 mm/m2, p <0.004), and end-diastolic LV volume (61.82 vs 67.09 ml/m2, p <0.010) compared with controls, without changes in systolic function and diastolic relaxation/filling indexes. A lower burden of ventricular arrhythmias on exercise was observed in HT athletes (1.5% vs 8.6% in those without therapy, p = 0.040). Linear regression analysis showed that HT had an independent effect on LV end-diastolic diameter indexed (p = 0.014), LV end-diastolic volume indexed (p = 0.030), and LV mass indexed (p = 0.020). In conclusion, chronic treatment with HT in female athletes is associated with less cardiac remodeling, including a lower LV cavity, volume, and mass, with preserved systolic and diastolic function, and decreased burden of exercise-induced ventricular arrhythmias. HT, therefore, appears to be responsible for a more economic but equally efficient cardiac adaptation to intensive athletic conditioning.

Myocardial sodium-glucose cotransporter 2 expression and cardiac remodelling in patients with severe aortic stenosis: The BIO-AS study

AIM

Cardiac remodelling plays a major role in the prognosis of patients with aortic stenosis (AS) and could impact the benefits of aortic valve replacement. Our study aimed to evaluate the expression of sodium-glucose cotransporter 2 (SGLT2) gene and protein in patients with severe AS stratified in high gradient (HG) and low flow-low gradient (LF-LG) AS and its association with cardiac functional impairments.

METHODS AND RESULTS

Gene expression and protein levels of main biomarkers of cardiac fibrosis (galectin-3, sST2, serpin-4, procollagen type I amino-terminal peptide, procollagen type I carboxy-terminal propeptide, collagen, transforming growth factor [TGF]-β), inflammation (growth differentiation factor-15, interleukin-6, nuclear factor-κB [NF-κB]), oxidative stress (superoxide dismutase 1 [SOD1] and 2 [SOD2]), and cardiac metabolism (sodium-hydrogen exchanger, peroxisome proliferator-activated receptor [PPAR]-α, PPAR-γ, glucose transporter 1 [GLUT1] and 4 [GLUT4]) were evaluated in blood samples and heart biopsies of 45 patients with AS. Our study showed SGLT2 gene and protein hyper-expression in patients with LF-LG AS, compared to controls and HG AS (p < 0.05). These differences remained significant even after adjusting for age, gender, body mass index, history of diabetes mellitus, arterial hypertension, and coronary artery disease. SGLT2 gene expression was positively correlated with: (i) TGF-β (r = 0.72, p < 0.001) and collagen (r = 0.73, p < 0.001) as markers of fibrosis; (ii) NF-κB (r = 0.36, p < 0.01) and myocardial interleukin-6 (r = 0.68, p < 0.001) as markers of inflammation: (iii) SOD2 (r = -0.38, p < 0.006) as a marker of oxidative stress; (iv) GLUT4 (r = 0.33, p < 0.02) and PPAR-α (r = 0.36, p < 0.01) as markers of cardiac metabolism.

CONCLUSION

In patients with LF-LG AS, SGLT2 gene and protein were hyper-expressed in cardiomyocytes and associated with myocardial fibrosis, inflammation, and oxidative stress.