Left ventricular remodeling in heart failure: current concepts in clinical significance and assessment

miR-320a in serum exosomes promotes myocardial fibroblast proliferation via regulating the PIK3CA/Akt/mTOR signaling pathway in HEH2 cells

MicroRNAs (miRNAs/miRs) serve an important role in the pathogenesis of chronic heart failure (CHF). A number of reports have illustrated the regulatory effect of serum exosomal miRNA on myocardial fibrosis. The present study aimed to investigate the expression of miR-320a in serum exosomes, as well as the effect of miR-320a on myocardial fibroblast proliferation. Serum exosome samples from 10 patients with CHF and 5 healthy volunteers were obtained and characterized. mRNA and protein expression levels were measured via reverse transcription-quantitative PCR and western blotting, respectively. The content of soluble growth stimulation expressed gene 2 (sST2) was determined via ELISA. HEH2 cell viability and apoptosis were detected by performing MTT assays and flow cytometry, respectively. The results demonstrated that serum miR-320a expression levels and sST2 content were significantly increased in patients with CHF compared with healthy controls, and the expression of serum miR-320a was significantly correlated with clinical CHF indexes. miR-320a expression levels were significantly increased in exosomes isolated from patients with CHF compared with those isolated from healthy controls. Phosphoinositide-3-kinase catalytic α polypeptide gene (PIK3CA) expression levels and sST2 content were increased in HEH2 cells following transfection with miR-320a mimics compared with NC-mimic, whereas miR-320a inhibitor displayed contrasting effects by reduced the cell viability and apoptosis in myocardial fibroblasts compared with the NC-inhibitor group. The protein expression levels of collagen I, collagen III, α-smooth muscle actin, phosphorylated (p)-mTOR (ser 2448)/mTOR, p-Akt (ser 473)/Akt, p-Akt (thr 308)/Akt and PIK3CA were significantly increased in miR-320a mimic-transfected HEH2 cells compared with the NC-mimics groups. By contrast, miR-320a inhibitor notably downregulated the expression levels of these proteins compared with the NC-inhibitor group. Collectively, the results of the present study demonstrated that miR-320a promoted myocardial fibroblast proliferation via regulating the PIK3CA/Akt/mTOR signaling pathway in HEH2 cells, suggesting that serum exosomal miR-320a may serve as a potential biomarker for the diagnosis of CHF.

Left Ventricular Remodeling and Myocardial Work: Results From the Population-Based STAAB Cohort Study

Introduction: Left ventricular (LV) dilatation and LV hypertrophy are acknowledged precursors of myocardial dysfunction and ultimately of heart failure, but the implications of abnormal LV geometry on myocardial function are not well-understood. Non-invasive LV myocardial work (MyW) assessment based on echocardiography-derived pressure-strain loops offers the opportunity to study detailed myocardial function in larger cohorts. We aimed to assess the relationship of LV geometry with MyW indices in general population free from heart failure.

Methods and Results: We report cross-sectional baseline data from the Characteristics and Course of Heart Failure Stages A-B and Determinants of Progression (STAAB) cohort study investigating a representative sample of the general population of Würzburg, Germany, aged 30–79 years. MyW analysis was performed in 1,926 individuals who were in sinus rhythm and free from valvular disease (49.3% female, 54 ± 12 years). In multivariable regression, higher LV volume was associated with higher global wasted work (GWW) (+0.5 mmHg% per mL/m², p < 0.001) and lower global work efficiency (GWE) (−0.02% per mL/m², p < 0.01), while higher LV mass was associated with higher GWW (+0.45 mmHg% per g/m², p < 0.001) and global constructive work (GCW) (+2.05 mmHg% per g/m², p < 0.01) and lower GWE (−0.015% per g/m², p < 0.001). This was dominated by the blood pressure level and also observed in participants with normal LV geometry and concomitant hypertension.

Conclusion: Abnormal LV geometric profiles were associated with a higher amount of wasted work, which translated into reduced work efficiency. The pattern of a disproportionate increase in GWW with higher LV mass might be an early sign of hypertensive heart disease.

Prognostic value of cardiovascular magnetic resonance left ventricular volumetry and geometry in patients receiving an implantable cardioverter defibrillator

BACKGROUND

Current indications for implantable cardioverter defibrillator (ICD) implantation for sudden cardiac death prevention rely primarily on left ventricular (LV) ejection fraction (LVEF). Currently, two different contouring methods by cardiovascular magnetic resonance (CMR) are used for LVEF calculation. We evaluated the comparative prognostic value of these two methods in the ICD population, and if measures of LV geometry added predictive value.

METHODS

In this retrospective, 2-center observational cohort study, patients underwent CMR prior to ICD implantation for primary or secondary prevention from January 2005 to December 2018. Two readers, blinded to all clinical and outcome data assessed CMR studies by: (a) including the LV trabeculae and papillary muscles (TPM) (trabeculated endocardial contours), and (b) excluding LV TPM (rounded endocardial contours) from the total LV mass for calculation of LVEF, LV volumes and mass. LV sphericity and sphere-volume indices were also calculated. The primary outcome was a composite of appropriate ICD shocks or death.

RESULTS

Of the 372 consecutive eligible patients, 129 patients (34.7%) had appropriate ICD shock, and 65 (17.5%) died over a median duration follow-up of 61 months (IQR 38-103). LVEF was higher when including TPM versus excluding TPM (36% vs. 31%, p < 0.001). The rate of appropriate ICD shock or all-cause death was higher among patients with lower LVEF both including and excluding TPM (p for trend = 0.019 and 0.004, respectively). In multivariable models adjusting for age, primary prevention, ischemic heart disease and late gadolinium enhancement, both LVEF (HR per 10% including TPM 0.814 [95%CI 0.688-0.962] p = 0.016, vs. HR per 10% excluding TPM 0.780 [95%CI 0.639-0.951] p = 0.014) and LV mass index (HR per 10 g/m2 including TPM 1.099 [95%CI 1.027-1.175] p = 0.006; HR per 10 g/m2 excluding TPM 1.126 [95%CI 1.032-1.228] p = 0.008) had independent prognostic value. Higher LV end-systolic volumes and LV sphericity were significantly associated with increased mortality but showed no added prognostic value.

CONCLUSION

Both CMR post-processing methods showed similar prognostic value and can be used for LVEF assessment. LVEF and indexed LV mass are independent predictors for appropriate ICD shocks and all-cause mortality in the ICD population.

Expedient assessment of post-infarct remodeling by native cardiac magnetic resonance imaging in mice

Novel therapeutic strategies aiming at improving the healing process after an acute myocardial infarction are currently under intense investigation. The mouse model plays a central role for deciphering the underlying mechanisms on a molecular and cellular level. Therefore, we intended to assess in-vivo post-infarct remodeling as comprehensively as possible using an expedient native magnetic resonance imaging (MRI) in the two most prominent infarct models, permanent ligation (PL) of the left anterior descending artery (LAD) versus ischemia reperfusion (I/R). Mice were subjected to either permanent or transient (45 min) occlusion of the LAD. After 3 weeks, examinations were performed with a 7-Tesla small animal MRI system. Data analysis was performed with the freely available software Segment. PL resulted in a massive dilation of the left ventricle, accompanied by hypertrophy of the non-infarcted myocardium and a decline of contractile function. These effects were less pronounced following I/R compared to healthy animals. Single plane assessments were not sufficient to capture the specific differences of left ventricular (LV) properties between the two infarct models. Bulls-eye plots were found to be an ideal tool for qualitative LV wall assessment, whereas a multi-slice sector-based analysis of wall regions is ideal to determine differences in hypertrophy, lateral wall thinning and wall thickening on a quantitative level. We combine the use of polar map-based analysis of LV wall properties with volumetric measurements using simple CINE CMR imaging. Our strategy represents a versatile and easily available tool for serial assessment of the LV during the remodeling process. Our study contributes to a better understanding of the effects of novel therapies targeting the healing of damaged myocardium.

New approach for quantification of left ventricular function from low-dose gated bloodpool SPECT: Validation and comparison with conventional methods in patients

BACKGROUND

Planar equilibrium radionuclide angiocardiography (ERNA) has been used as the gold standard for assessment of left ventricular (LV) function for over three decades. However, this imaging modality has recently gained less favor due to growing concerns about radiation exposure. We developed a novel approach that involves integrating short axis slices of gated bloodpool SPECT for quantification of LV function with improved signal-to-noise ratio and reduced radioactive dose while maintaining image quality and quantitative precision.

METHODS

Twenty patients referred for ERNA underwent standard in vitro 99mTc-labeling of red blood cells (RBC), and were initially imaged following a low-dose (~ 8 mCi) injection using a dedicated cardiac SPECT camera, and then had planar imaging following a high-dose (~ 25 mCi) injection. Four different quantification methods were utilized to assess the LV function and were compared for quantitative precision and inter-observer reproducibility of the quantitative assessments.

RESULTS

The Yale method resulted in the most consistent assessment of LV function compared with the gold standard high-dose ERNA method, along with excellent inter-observer reproducibility.

CONCLUSIONS

The new low-dose 99mTc-RBC imaging method provides precise quantification of LV function with a greater than 67% reduction in dose and may potentially improve assessment of regional function.

Percutaneous Mitral Valve Annuloplasty in Patients With Secondary Mitral Regurgitation and Severe Left Ventricular Enlargement

OBJECTIVES

This study sought to determine the effect of percutaneous mitral valve annuloplasty with the Carillon device versus guideline-directed medical therapy (GDMT) alone in patients with secondary mitral regurgitation (MR) and severe left ventricular (LV) enlargement.

BACKGROUND

The clinical impact of the Carillon device in patients with severe LV dilation is not well established.

METHODS

This is a pooled analysis involving 3 prospective trials (TITAN [Transcatheter Implantation of Carillon Mitral Annuloplasty Device], TITAN II, and REDUCE FMR [CARILLON Mitral Contour System for Reducing Functional Mitral Regurgitation] trials) in which patients with functional MR and severe LV enlargement (LV end-diastolic diameter >65 mm) were treated with GDMT and the Carillon device versus GDMT alone. Key outcomes of this analysis were changes over 1 year of follow-up in mitral valve and LV echocardiographic parameters, functional outcome, quality of life, mortality, and heart failure hospitalization (HFH).

RESULTS

A total of 95 patients (67 in the Carillon group, 28 in the GDMT group) with severe LV enlargement were included. In the Carillon group, all mitral valve and LV morphology parameters were significantly improved at 1 year. Regurgitant volume decreased by 12 ml (p < 0.001), MR grade decreased by 0.6 U (p < 0.001), LV end-diastolic volume decreased by 25 cm3 (p = 0.005), and LV end-systolic volume decreased by 21 cm3 (p = 0.01). Significant functional improvement differences were also noted between the Carillon group and the GDMT group including an improvement of Kansas City Cardiomyopathy Questionnaire score (15 ± 4 vs. 6 ± 6; p = 0.03). The incidence of HFH was 29.9% versus 50.0% and the cumulative rate of HFH was 0.43 versus 0.75 (p < 0.001).

CONCLUSIONS

In patients with functional MR and severe LV enlargement, the Carillon device improved mitral valve function, LV morphology, and functional outcome compared with patients receiving GDMT only. Preoperative LV dimension should not be a limiting factor when evaluating patient eligibility or anticipated response to therapy with the Carillon device.

Biologics and their delivery systems: Trends in myocardial infarction

Cardiovascular disease is the leading cause of death around the world, in which myocardial infarction (MI) is a precipitating event. However, current therapies do not adequately address the multiple dysregulated systems following MI. Consequently, recent studies have developed novel biologic delivery systems to more effectively address these maladies. This review utilizes a scientometric summary of the recent literature to identify trends among biologic delivery systems designed to treat MI. Emphasis is placed on sustained or targeted release of biologics (e.g. growth factors, nucleic acids, stem cells, chemokines) from common delivery systems (e.g. microparticles, nanocarriers, injectable hydrogels, implantable patches). We also evaluate biologic delivery system trends in the entire regenerative medicine field to identify emerging approaches that may translate to the treatment of MI. Future developments include immune system targeting through soluble factor or chemokine delivery, and the development of advanced delivery systems that facilitate the synergistic delivery of biologics.

Therapies Targeted at Non-Coding RNAs in Prevention and Limitation of Myocardial Infarction and Subsequent Cardiac Remodeling-Current Experience and Perspectives

Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented.

Lack of Relationship between Fibrosis-Related Biomarkers and Cardiac Magnetic Resonance-Assessed Replacement and Interstitial Fibrosis in Dilated Cardiomyopathy

The relationship between circulating fibrosis-related molecules and magnetic resonance-assessed cardiac fibrosis in dilated cardiomyopathy (DCM) is poorly understood. To compare circulating biomarkers between DCM patients with high and low fibrosis burdens, we performed a prospective, single-center, observational study. The study population was composed of 100 DCM patients (87 male, mean age 45.2 ± 11.8 years, mean ejection fraction 29.7% ± 10.1%). Replacement fibrosis was quantified by means of late gadolinium enhancement (LGE), whereas interstitial fibrosis was assessed via extracellular volume (ECV). Plasma concentrations of cardiotrophin-1, growth differentiation factor-15, platelet-derived growth factor, procollagen I C-terminal propeptide, procollagen III N-terminal propeptide, and C-terminal telopeptide of type I collagen were measured. There were 44% patients with LGE and the median ECV was 27.7%. None of analyzed fibrosis serum biomarkers were associated with the LGE or ECV, whereas NT-proBNP was independently associated with both LGE and ECV, and troponin T was associated with ECV. None of the circulating fibrosis markers differentiated between DCM patients with and without replacement fibrosis, or patients stratified according to median ECV. However, cardiac-specific markers, such as NT-proBNP and hs-TnT, were associated with fibrosis. Levels of circulating markers of fibrosis seem to have no utility in the diagnosis and monitoring of cardiac fibrosis in DCM.

Increased oxygenation is associated with myocardial inflammation and adverse regional remodeling after acute ST-segment elevation myocardial infarction

OBJECTIVES

To explore the relationships between oxygenation signal intensity (SI) with myocardial inflammation and regional left ventricular (LV) remodeling in reperfused acute ST-segment elevation myocardial infarction (STEMI) using oxygenation-sensitive cardiovascular magnetic resonance (OS-CMR).

METHODS

Thirty-three STEMI patients and 22 age- and sex-matched healthy volunteers underwent CMR. The protocol included cine function, OS imaging, precontrast T1 mapping, T2 mapping, and late gadolinium enhancement (LGE) imaging. A total of 880 LV segments were included for analysis based on the American Heart Association 16-segment model. For validation, 15 pigs (10 myocardial infarction (MI) model animals and 5 controls) received CMR and were sacrificed for immunohistochemical analysis.

RESULTS

In the patient study, the acute oxygenation SI showed a stepwise rise among remote, salvaged, and infarcted segments compared with healthy myocardium. At convalescence, all oxygenation SI values besides those in infarcted segments with microvascular obstruction decreased to similar levels. Acute oxygenation SI was associated with early myocardial injury (T1: r = 0.38; T2: r = 0.41; all p < 0.05). Segments with higher acute oxygenation SI values exhibited thinner diastolic walls and decreased wall thickening during follow-up. Multivariable regression modeling indicated that acute oxygenation SI (β = 2.66; p < 0.05) independently predicted convalescent segment adverse remodeling (LV wall thinning). In the animal study, alterations in oxygenation SI were correlated with histological inflammatory infiltrates (r = 0.59; p < 0.001).

CONCLUSIONS

Myocardial oxygenation by OS-CMR could be used as a quantitative imaging biomarker to assess myocardial inflammation and predict convalescent segment adverse remodeling after STEMI.

KEY POINTS

• Oxygenation signal intensity (SI) may be an imaging biomarker of inflammatory infiltration that could be used to assess the response to anti-inflammatory therapies in the future. • Oxygenation SI early after myocardial infarction (MI) was associated with left ventricular segment injury at acute phase and could predict regional functional recovery and adverse remodeling late after acute MI. • Oxygenation SI demonstrated a stepwise increase among remote, salvaged, and infarcted segments. Infarcted zones with microvascular obstruction demonstrated a higher oxygenation SI than those without. However, the former showed less pronounced changes over time.

Splenic Volume Index Determined Using Computed Tomography upon Admission Is Associated with Readmission for Heart Failure Among Patients with Acute Decompensated Heart Failure

The spleen is associated with inflammation, and the size of the spleen is affected by hemodynamic congestion and sympathetic stimulation. However, the association between splenic size and prognosis in patients with heart failure remains unknown. Between January 2015 and March 2017, we analyzed 125 patients with acute decompensated heart failure who were assessed by computed tomography (CT) on the day of admission. The spleen was measured by 3-dimensional CT and then the patients were assigned to groups according to their median splenic volume indexes (SpVi; splenic volume/body surface area). We then compared their baseline characteristics and rates of readmission for heart failure after one year. The median SpVi was 63.7 (interquartile range: 44.7-95.3) cm³/m². Age did not significantly differ between the groups. Patients with a high SpVi had more significantly enlarged left atria and left ventricles. Multiple regression analysis identified significant positive correlations between SpVi and posterior wall thickness as well as left ventricular mass index. Kaplan-Meier analysis revealed lower event-free rates in the patients with a high, than a low SpVi (P = 0.041, log-rank test). After adjustment for potential cofounding factors, SpVi was independently associated with readmission for heart failure (Hazard ratio, 2.25; 95% confidence interval, 1.01-5.02; P = 0.047). In conclusion, increased splenic volume is independently associated with readmission for heart failure among patients with acute decompensated heart failure.

Effect of Neprilysin Inhibition on Left Ventricular Remodeling in Patients With Asymptomatic Left Ventricular Systolic Dysfunction Late After Myocardial Infarction

BACKGROUND

Patients with left ventricular (LV) systolic dysfunction after myocardial infarction are at a high risk of developing heart failure. The addition of neprilysin inhibition to renin angiotensin system inhibition may result in greater attenuation of adverse LV remodeling as a result of increased levels of substrates for neprilysin with vasodilatory, antihypertrophic, antifibrotic, and sympatholytic effects.

METHODS

We performed a prospective, multicenter, randomized, double-blind, active-comparator trial comparing sacubitril/valsartan 97/103 mg twice daily with valsartan 160 mg twice daily in patients ≥3 months after myocardial infarction with a LV ejection fraction ≤40% who were taking a renin angiotensin system inhibitor (equivalent dose of ramipril ≥2.5 mg twice daily) and a β-blocker unless contraindicated or intolerant. Patients in New York Heart Association class ≥II or with signs and symptoms of heart failure were excluded. The primary outcome was change from baseline to 52 weeks in LV end-systolic volume index measured using cardiac magnetic resonance imaging. Secondary outcomes included other magnetic resonance imaging measurements of LV remodeling, change in NT-proBNP (N-terminal pro-B-type natriuretic peptide) and high-sensitivity cardiac troponin I, and a patient global assessment of change questionnaire.

RESULTS

From July 2018 to June 2019, we randomized 93 patients with the following characteristics: mean age, 60.7±10.4 years; median time from myocardial infarction, 3.6 years (interquartile range, 1.2-7.2); mean LV ejection fraction, 36.8%±7.1%; and median NT-proBNP, 230 pg/mL (interquartile range, 124-404). Sacubitril/valsartan, compared with valsartan, did not significantly reduce LV end-systolic volume index; adjusted between-group difference, -1.9 mL/m² (95% CI, -4.9 to 1.0); P=0.19. There were no significant between-group differences in NT-proBNP, high-sensitivity cardiac troponin I, LV end-diastolic volume index, left atrial volume index, LV ejection fraction, LV mass index, or patient global assessment of change.

CONCLUSIONS

In patients with asymptomatic LV systolic dysfunction late after myocardial infarction, treatment with sacubitril/valsartan did not have a significant reverse remodeling effect compared with valsartan. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03552575.

Long-term prognosis analysis of PARACHUTE device implantation in patients with ischemic heart failure: a single-center experience of Chinese patients

BACKGROUND

Heart failure (HF) is one of the leading causes of mortality and morbidity. The PARACHUTE device is designed to partition for left ventricular (LV) apical aneurysm post extensive anterior myocardial infarction (MI). However, the long-term prognosis of the PARACHUTE device post-implantation is unclear.

METHODS

From November 2015 to April 2017, six subjects with New York Heart Association Classes II, III and IV ischemic HF, LV ejection fraction between (LVEF) 15 and 40%; and LV anterior apical aneurysm were enrolled in our center. The cumulative event rates for MI, hospitalization, and mortality were documented. Further assessment of LVEF, LV end-diastolic diameter (LVEDD), and estimated pulmonary artery pressure were determined by echocardiography core laboratory. For quantitative data comparison, paired t-test was employed.

RESULTS

Device implantation was successful in all six enrolled subjects, and acute device association adverse events were not observed. At 4.6 ± 1.7 years follow-up, major adverse cardiac events (MACEs) were found in 50% patients, and the survival rate was 86.7%. We observed that the LVEF was significantly elevated after deployment (46.00 ± 6.00% vs. 35.83 ± 1.47%, P = 0.009). Besides, the LVEDD elevated after MI (51.17 ± 3.71 vs. 62.83 ± 3.25, P < 0.001) was revealed, but the device sustained preserved LVEDD after implantation.

CONCLUSION

The PARACHUTE device is an alternative therapy for patients with severe LV maladaptive remodeling. However, the device seems to increase the HF ratio.

TRIAL REGISTRATION

NCT02240940.

Myocardial Infarction Induces Cardiac Fibroblast Transformation within Injured and Noninjured Regions of the Mouse Heart

Heart failure (HF) is associated with pathological remodeling of the myocardium, including the initiation of fibrosis and scar formation by activated cardiac fibroblasts (CFs). Although early CF-dependent scar formation helps prevent cardiac rupture by maintaining the heart's structural integrity, ongoing deposition of the extracellular matrix in the remote and infarct regions can reduce tissue compliance, impair cardiac function, and accelerate progression to HF. In our study, we conducted mass spectrometry (MS) analysis to identify differentially altered proteins and signaling pathways between CFs isolated from 7 day sham and infarcted murine hearts. Surprisingly, CFs from both the remote and infarct regions of injured hearts had a wide number of similarly altered proteins and signaling pathways that were consistent with fibrosis and activation into pathological myofibroblasts. Specifically, proteins enriched in CFs isolated from MI hearts were involved in pathways pertaining to cell-cell and cell-matrix adhesion, chaperone-mediated protein folding, and collagen fibril organization. These results, together with principal component analyses, provided evidence of global CF activation postinjury. Interestingly, however, direct comparisons between CFs from the remote and infarct regions of injured hearts identified 15 differentially expressed proteins between MI remote and MI infarct CFs. Eleven of these proteins (Gpc1, Cthrc1, Vmac, Nexn, Znf185, Sprr1a, Specc1, Emb, Limd2, Pawr, and Mcam) were higher in MI infarct CFs, whereas four proteins (Gstt1, Gstm1, Tceal3, and Inmt) were higher in MI remote CFs. Collectively, our study shows that MI injury induced global changes to the CF proteome, with the magnitude of change reflecting their relative proximity to the site of injury.

Inflammageing in the cardiovascular system: mechanisms, emerging targets, and novel therapeutic strategies

In the elderly population, pathological inflammation has been associated with ageing-associated diseases. The term 'inflammageing', which was used for the first time by Franceschi and co-workers in 2000, is associated with the chronic, low-grade, subclinical inflammatory processes coupled to biological ageing. The source of these inflammatory processes is debated. The senescence-associated secretory phenotype (SASP) has been proposed as the main origin of inflammageing. The SASP is characterised by the release of inflammatory cytokines, elevated activation of the NLRP3 inflammasome, altered regulation of acetylcholine (ACh) nicotinic receptors, and abnormal NAD+ metabolism. Therefore, SASP may be 'druggable' by small molecule therapeutics targeting those emerging molecular targets. It has been shown that inflammageing is a hallmark of various cardiovascular diseases, including atherosclerosis, hypertension, and adverse cardiac remodelling. Therefore, the pathomechanism involving SASP activation via the NLRP3 inflammasome; modulation of NLRP3 via α7 nicotinic ACh receptors; and modulation by senolytics targeting other proteins have gained a lot of interest within cardiovascular research and drug development communities. In this review, which offers a unique view from both clinical and preclinical target-based drug discovery perspectives, we have focused on cardiovascular inflammageing and its molecular mechanisms. We have outlined the mechanistic links between inflammageing, SASP, interleukin (IL)-1β, NLRP3 inflammasome, nicotinic ACh receptors, and molecular targets of senolytic drugs in the context of cardiovascular diseases. We have addressed the 'druggability' of NLRP3 and nicotinic α7 receptors by small molecules, as these proteins represent novel and exciting targets for therapeutic interventions targeting inflammageing in the cardiovascular system and beyond.

Predictors of improvement of left ventricular systolic function after catheter ablation of persistent atrial fibrillation in patients with heart failure with reduced ejection fraction

Although several studies have suggested that catheter ablation (CA) of atrial fibrillation (AF) can improve left ventricular ejection fraction (LVEF) in patients with heart failure with reduced ejection fraction (HFrEF), the predictor of improvement of LVEF is unclear. A total of 401 patients with persistent AF underwent an initial CA between September 2014 and October 2019 in our hospital. Among them, we analyzed consecutive patients with moderately or severely reduced LVEF (< 50%) measured by transthoracic echocardiography (TTE) within 2 months before CA and underwent follow-up TTE during sinus rhythm at 6 months or more after CA. These patients were categorized into two groups: improve group (I group) with the absolute improvement of LVEF ≥ 10% at follow-up TTE, and non- improve group (NI group) with the absolute improvement of LVEF < 10% at follow-up TTE. We compared patient characteristics, ablation procedures, and clinical outcomes between the two groups. 81 patients were analyzed, and I group consisted of 48 patients (59%). In the univariate analysis, absence of ischemic cardiomyopathy, left ventricular end-diastolic diameter (LVEDD), and absence of recurrence of AF between 3 and 6 months after CA were associated with improvement of LVEF. A receiver operating characteristics analysis determined the suitable cut-off value for LVEDD was 53 mm (sensitivity: 62.2%, specificity: 86.2%, area under curve: 0.762). A multivariate analysis showed that LVEDD < 53 mm was independently associated with improvement of LVEF (odds ratio 2.58, 95% confidence interval 1.29-6.12; P = 0.021). In conclusion, LVEDD < 53 mm might be an independent predictor of improvement of LVEF after CA of persistent AF in HFrEF patients.

A New Therapeutic Candidate for Cardiovascular Diseases: Berberine

Cardiovascular diseases (CVD) are the leading cause of death in the world. However, due to the limited effectiveness and potential adverse effects of current treatments, the long-term prognosis of CVD patients is still discouraging. In recent years, several studies have found that berberine (BBR) has broad application prospects in the prevention and treatment of CVD. Due to its effectiveness and safety for gastroenteritis and diarrhea caused by bacterial infections, BBR has been widely used in China and other Asian countries since the middle of the last century. The development of pharmacology also provides evidence for the multi-targets of BBR in treating CVD. Researches on CVD, such as arrhythmia, atherosclerosis, dyslipidemia, hypertension, ischemic heart disease, myocarditis and cardiomyopathy, heart failure, etc., revealed the cardiovascular protective mechanisms of BBR. This review systematically summarizes the pharmacological research progress of BBR in the treatment of CVD in recent years, confirming that BBR is a promising therapeutic option for CVD.

Association of Hypertensive Disorders of Pregnancy With Left Ventricular Remodeling Later in Life

BACKGROUND

Hypertensive disorders of pregnancy (HDP) are associated with short-term cardiac structure and function abnormalities, but later life changes are not well studied.

OBJECTIVES

This study aimed to determine if HDP history is associated with echocardiographic differences 8 to 10 years after delivery, and if subgroups with placental maternal vascular malperfusion (MVM) lesions or current hypertension may be particularly affected.

METHODS

Women with pregnancies delivered from 2008 to 2009 were selected from a clinical cohort with abstracted pregnancy and placental pathology data to undergo transthoracic echocardiography (2017 to 2020). Medical history, blood pressure, and weight were measured at the study visit.

RESULTS

The authors enrolled 132 women (10 ± 1 years post-delivery, age 38 ± 6 years): 102 with normotensive pregnancies and 30 with HDP: pre-eclampsia (n = 21) or gestational hypertension (n = 9). Compared with women with normotensive pregnancies, those with HDP history were more likely to have current hypertension (63% vs. 26%; p < 0.001). After adjusting for age, race, MVM lesions, body mass index, current hypertension, and hemoglobin A1c, women with HDP history had higher interventricular septal thickness (β = 0.08; p = 0.04) and relative wall thickness (β = 0.04; p = 0.04). In subgroup analyses, those with both HDP history and current hypertension had a higher proportion of left ventricular remodeling (79.0%) compared with all other groups (only HDP [36.4%; p = 0.01], only current hypertension [46.2%; p = 0.02], and neither HDP nor hypertension [38.2%; p < 0.001]), and lower mitral inflow E/A and annular e'. Accounting for placental MVM lesions did not impact results.

CONCLUSIONS

Women with both HDP history and current hypertension have pronounced differences in left ventricular structure and function a decade after pregnancy, warranting continued surveillance and targeted therapies for cardiovascular disease prevention.

The Effect of Blood Lipids on the Left Ventricle: A Mendelian Randomization Study

Background

Cholesterol and triglycerides are among the most well-known risk factors for cardiovascular disease.

Objectives

This study investigated whether higher low-density lipoprotein (LDL) cholesterol and triglyceride levels and lower high-density lipoprotein cholesterol level are causal risk factors for changes in prognostically important left ventricular (LV) parameters.

Methods

One-sample Mendelian randomization (MR) of 17,311 European individuals from the UK Biobank with paired lipid and cardiovascular magnetic resonance data was performed. Two-sample MR was performed by using summary-level data from the Global Lipid Genetics Consortium (n = 188,577) and UK Biobank Cardiovascular Magnetic Resonance substudy (n = 16,923) for sensitivity analyses.

Results

In 1-sample MR analysis, higher LDL cholesterol was causally associated with higher LV end-diastolic volume (β = 1.85 ml; 95% confidence interval [CI]: 0.59 to 3.14 ml; p = 0.004) and higher LV mass (β = 0.81 g; 95% CI: 0.11 to 1.51 g; p = 0.023) and triglycerides with higher LV mass (β = 1.37 g; 95% CI: 0.45 to 2.3 g; p = 0.004). High-density lipoprotein cholesterol had no significant association with any LV parameter. Similar results were obtained by using 2-sample MR. Observational analyses were frequently discordant with those derived from MR.

Conclusions

MR analysis demonstrates that LDL cholesterol and triglycerides are associated with adverse changes in cardiac structure and function, in particular in relation to LV mass. These findings suggest that LDL cholesterol and triglycerides may have a causal effect in influencing cardiac morphology in addition to their established role in atherosclerosis. (J Am Coll Cardiol 2020;76:2477-88).

Genistein Prevents Nitric Oxide Deficiency-Induced Cardiac Dysfunction and Remodeling in Rats

Genistein is an isoflavone found in soybeans. This study evaluates the protective effects of genistein on N^ω-nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertension, cardiac remodeling, and dysfunction in rats. Male Wistar rats were treated with L-NAME 40 mg/kg/day together for 5 weeks, with or without genistein at a dose of 40 or 80 mg/kg/day or lisinopril 5 mg/kg/day (n = 8 per group). Genistein prevented L-NAME-induced hypertension in rats. Increases in the left ventricular weight, metalloproteinase-2, metalloproteinase-9, and collagen type I intensity were observed in L-NAME rats, and these changes were attenuated in the genistein-treated group. Genistein reduced circulating angiotensin-converting enzyme activity and angiotensin II concentrations in L-NAME rats. L-NAME increased plasma and cardiac malondialdehyde and vascular superoxide generations, as well as reductions of serum and cardiac catalase activities in rats. Plasma nitrate/nitrite were protected in the genistein-treated group. Genistein prevented the L-NAME-induced overexpression of angiotensin II receptor type I (AT₁R), nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit 2 (gp91^phox), and transforming growth factor beta I (TGF-β1) in hypertensive rats. In conclusion, genistein exhibited a cardioprotective effect in hypertensive rats in this study. The molecular mechanisms might be mediated by suppression of oxidative stress through the Ang II/AT₁R/NADPH oxidase/TGF-β1 signaling pathway.

Eccentric Left Ventricular Hypertrophy and Left and Right Cardiac Function in Chronic Heart Failure with or without Coexisting COPD: Impact on Exercise Performance

Aim

Our aim was to assess: 1) the impact of the eccentric left ventricular hypertrophy (ELVH) on exercise performance in patients diagnosed with chronic heart failure (CHF) alone and in patients with co-existing CHF and chronic obstructive pulmonary disease (COPD) and 2) the relationship between left and right cardiac function measurements obtained by doppler echocardiography, clinical characteristics and primary measures of cardiorespiratory fitness.

Methods

The current study included 46 patients (CHF:23 and CHF+COPD:23) that performed advanced pulmonary function tests, echocardiography and symptom-limited, incremental cardiopulmonary exercise testing (CPET) on a cycle ergometer.

Results

Patients with CHF+COPD demonstrated a lower work rate, peak oxygen uptake (VO₂), oxygen pulse, rate pressure product (RPP), circulatory power (CP) and ventilatory power (VP) compared to those only diagnosed with CHF. In addition, significant correlations were observed between VP and relative wall thickness (r: 0.45 p: 0.03),V_E/VCO₂ intercept and Mitral E/e' ratio (r: 0.70 p: 0.003) in the CHF group. Significant correlations were found between indexed left ventricle mass and RPP (r: -0.47; p: 0.02) and relative VO₂ and right ventricle diameter (r: -0.62; p: 0.001) in the CHF+COPD group.

Conclusion

Compared to a diagnosis of CHF alone, a combined diagnosis of CHF+COPD induced further impairments in cardiorespiratory fitness. Moreover, echocardiographic measures of cardiac function are related to cardiopulmonary exercise performance and therefore appear to be an important therapeutic target when attempting to improve exercise performance and functional capacity.

Rationale and methods of a randomized trial evaluating the effect of neprilysin inhibition on left ventricular remodelling

AIMS

In patients at high risk of heart failure following myocardial infarction (MI) as a result of residual left ventricular systolic dysfunction (LVSD), the angiotensin receptor neprilysin inhibitor sacubitril/valsartan may result in a greater attenuation of adverse left ventricular (LV) remodelling than renin angiotensin aldosterone system inhibition alone, due to increased levels of substrates for neprilysin with vasodilatory, anti-hypertrophic, anti-fibrotic, and sympatholytic effects.

METHODS

We designed a randomized, double-blinded, active-comparator trial to examine the effect of sacubitril/valsartan to the current standard of care in reducing adverse LV remodelling in patients with asymptomatic LVSD following MI. Eligible patients were ≥3 months following MI, had an LV ejection fraction ≤40% as measured by echocardiography, were New York Heart Association functional classification I, tolerant of an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker at equivalent dose of ramipril 2.5 mg twice daily or greater, and taking a beta-blocker unless contraindicated or intolerant. Patients were randomized to sacubitril/valsartan (target dose 97/103 mg twice daily) or valsartan (target dose 160 mg twice daily). The primary endpoint will be change in LV end-systolic volume indexed for body surface area measured using cardiac magnetic resonance imaging over 52 weeks from randomization. Secondary endpoints include other magnetic resonance imaging-based metrics of LV remodelling, biomarkers associated with LV remodelling and neurohumoral activation, and change in patient well-being assessed using a patient global assessment questionnaire.

CONCLUSIONS

This trial will investigate the effect of neprilysin inhibition on LV remodelling and the neurohumoral actions of sacubitril/valsartan in patients with asymptomatic LVSD following MI.

Eccentric hypertrophy in an animal model of mid- and long-term premature ventricular contraction-induced cardiomyopathy

BACKGROUND

Tachycardia and heart rate irregularity are proposed triggers of premature ventricular contraction-induced cardiomyopathy (PVC-cardiomyopathy). Bigeminal premature atrial and ventricular contractions (PACs and PVCs) increase heart rate and result in rhythm irregularities but differ in their effects on ventricular synchrony. Comparing chronic bigeminal PACs with PVCs would provide insights into mechanisms of PVC-cardiomyopathy.

OBJECTIVE

To compare the impact of chronic PACs and PVCs on ventricular hemodynamics, structure, and function.

METHODS

Pacemakers were implanted in 27 canines to reproduce atrial (PACs, n = 7) or ventricular bigeminy (PVCs, n = 11) for 12 weeks, and compared to sham-operated animals (n = 9). Four additional animals were exposed to long-term bigeminal PVCs (48 weeks). Hemodynamic changes were assessed using a pressure-transducing catheter at baseline and 12 weeks. Cardiac remodeling was monitored by transthoracic echocardiography throughout the 12- and 48-week protocols in the respective groups.

RESULTS

PVC group demonstrated a significant decrease in left ventricular (LV) ejection fraction and contractility (max dP/dt), impaired LV lusitropy (min dP/dt), and increase in LV dimensions and LV mass at 12 weeks without further deterioration beyond 16 weeks. Despite increased LV mass, relative wall thickness decreased, consistent with eccentric hypertrophy. No significant cardiac remodeling was noted in either sham or PAC groups at 12 weeks.

CONCLUSION

In contrast to bigeminal PACs, PVCs result in a cardiomyopathy characterized by reduced LV ejection fraction, LV dilation, and eccentric hypertrophy that plateaus between 12 and 16 weeks. The lack of remodeling in chronic PACs suggests that tachycardia and heart rate irregularity do not play a significant role on the development of PVC-cardiomyopathy.

Advanced In Vitro Modeling to Study the Paradox of Mechanically Induced Cardiac Fibrosis

In heart failure, cardiac fibrosis is the result of an adverse remodeling process. Collagen is continuously synthesized in the myocardium in an ongoing attempt of the heart to repair itself. The resulting collagen depositions act counterproductively, causing diastolic dysfunction and disturbing electrical conduction. Efforts to treat cardiac fibrosis specifically have not been successful and the molecular etiology is only partially understood. The differentiation of quiescent cardiac fibroblasts to extracellular matrix-depositing myofibroblasts is a hallmark of cardiac fibrosis and a key aspect of the adverse remodeling process. This conversion is induced by a complex interplay of biochemical signals and mechanical stimuli. Tissue-engineered 3D models to study cardiac fibroblast behavior in vitro indicate that cyclic strain can activate a myofibroblast phenotype. This raises the question how fibroblast quiescence is maintained in the healthy myocardium, despite continuous stimulation of ultimately profibrotic mechanotransductive pathways. In this review, we will discuss the convergence of biochemical and mechanical differentiation signals of myofibroblasts, and hypothesize how these affect this paradoxical quiescence. Impact statement Mechanotransduction pathways of cardiac fibroblasts seem to ultimately be profibrotic in nature, but in healthy human myocardium, cardiac fibroblasts remain quiescent, despite continuous mechanical stimulation. We propose three hypotheses that could explain this paradoxical state of affairs. Furthermore, we provide suggestions for future research, which should lead to a better understanding of fibroblast quiescence and activation, and ultimately to new strategies for the prevention and treatment of cardiac fibrosis and heart failure.

Heartech® left ventricular partitioning device improves left ventricular systolic function of patients with chronic heart failure post-myocardial infarction at 1-year follow-up

OBJECTIVES

This study presents 1-year follow-up data of echocardiographic outcomes in patients who received the Heartech® left ventricular (LV) partitioning device (LVPD) (Xinrui Medical Equipment Co. Ltd., Shanghai, China).

BACKGROUND

Our first-in-man study of the Heartech® LVPD confirmed its safety and efficacy in patients with chronic heart failure (HF) post-myocardial infarction (MI) 1 month post-implantation. This subsequent study reports the echocardiographic outcomes of these patients at 1 year of follow-up.

METHODS

Fifteen patients with HF post-MI from three cardiac intervention centers in China were successfully implanted with the Heartech® LVPD via percutaneous ventricular restoration procedures. Echocardiographic parameters-including LV systolic function, diastolic function, two-dimensional speckle-tracking analysis, and right ventricular systolic function-were obtained before device implantation and at 1 month and 1 year postoperatively.

RESULTS

There was no deterioration of LV diastolic function, specific strain parameters, or right ventricular function at 1 year. Relative to the echocardiographic parameters recorded before the procedure, the LV ejection fraction (32.47 ± 6.98% vs. 42.5 ± 7.41%; p = .001) was significantly improved at 1 year, while the LV end-diastolic volume index (106.29 ± 28.01 vs. 83.30 ± 31.71; p = .005) and end-systolic volume index were significantly reduced (72.47 ± 22.77 vs. 50.00 ± 19.70; p = .001).

CONCLUSIONS

One-year echocardiographic follow-up results confirmed that no deterioration of LV diastolic function or specific strain parameters was observed and LV systolic function was significantly improved in patients with HF post-MI who were implanted with the Heartech® LVPD.

Results of surgical ventricular reconstruction in a specialized center and in comparison to the STICH trial: Rationale and study protocol for a patient-level pooled analysis

INTRODUCTION

Post-infarction left ventricular remodeling is associated with increased mortality in patients with ischemic heart disease. Surgical ventricular reconstruction (SVR) in addition to coronary artery bypass grafting (CABG) has been proposed to reduce left ventricular volume and improve clinical outcomes. The Surgical Treatment for Ischemic Heart Failure (STICH) trial found that the addition of SVR to CABG did not reduce the rates of death or rehospitalization in the 5 years after surgery compared to CABG alone. Like all randomized trials, STICH has limitations and it has been hypothesized that it may have underestimated the treatment effect of SVR. The aim of this study is to evaluate the results of SVR in one of the largest contemporary single-center series and to compare the results with those of the STICH trial using individual patient's data.

METHODS AND ANALYSIS

Individual data of patients who underwent SVR with or without CABG will be obtained from San Donato University Hospital in Milan. Using multivariable Cox regression analysis, significant prognostic indicators in this cohort will be identified. We will then compare the San Donato cohort to individual patient's data from the SVR arm of Hypothesis 2 of the STICH trial and from both arms of the STICH Extended Study (STICHES). To reduce confounders, propensity score adjustment will be used for this comparison. The primary endpoint will be all-cause mortality. Data will be merged and analyzed independently at Weill Cornell Medicine in New York.

Left ventricular regional glucose metabolism in combination with septal scar extent identifies CRT responders

BACKGROUND

Cardiac resynchronization therapy (CRT) is effective in selective heart failure (HF) patients, but non-response rate remains high. Positron emission tomography (PET) may provide a better insight into the pathophysiology of left ventricular (LV) remodeling; however, its role for evaluating and selecting patients for CRT remains uncertain.

PURPOSE

We investigated if regional LV glucose metabolism in combination with myocardial scar could predict response to CRT.

METHODS

Consecutive CRT-eligible HF patients underwent echocardiography, cardiac magnetic resonance (CMR), and ¹⁸F-fluorodeoxyglucose (FDG) PET within 1 week before CRT implantation. Echocardiography was additionally performed 12 months after CRT and end-systolic volume reduction ≥ 15% was defined as CRT response. Septal-to-lateral wall (SLR) FDG uptake ratio was calculated from static FDG images. Late gadolinium enhancement (LGE) CMR was analyzed semi-quantitatively to define scar extent.

RESULTS

We evaluated 88 patients (67 ± 10 years, 72% males). ¹⁸F-FDG SLR showed a linear correlation with volumetric reverse remodeling 12 months after CRT (r = 0.41, p = 0.0001). In non-ischemic HF patients, low FDG SLR alone predicted CRT response with sensitivity and specificity of more than 80%; however, in ischemic HF patients, specificity decreased to 46%, suggesting that in this cohort low SLR can also be caused by the presence of a septal scar. In the multivariate logistic regression model, including low FDG SLR, presence and extent of the scar in each myocardial wall, and current CRT guideline parameters, only low FDG SLR and septal scar remained associated with CRT response. Their combination could predict CRT response with sensitivity, specificity, negative, and positive predictive value of 80%, 83%, 70%, and 90%, respectively.

CONCLUSIONS

FDG SLR can be used as a predictor of CRT response and combined with septal scar extent, CRT responders can be distinguished from non-responders with high diagnostic accuracy. Further studies are needed to verify whether this imaging approach can prospectively be used to optimize patient selection.

Multiscale Analysis of Extracellular Matrix Remodeling in the Failing Heart

RATIONALE

Cardiac ECM (extracellular matrix) comprises a dynamic molecular network providing structural support to heart tissue function. Understanding the impact of ECM remodeling on cardiac cells during heart failure (HF) is essential to prevent adverse ventricular remodeling and restore organ functionality in affected patients.

OBJECTIVES

We aimed to (1) identify consistent modifications to cardiac ECM structure and mechanics that contribute to HF and (2) determine the underlying molecular mechanisms.

METHODS AND RESULTS

We first performed decellularization of human and murine ECM (decellularized ECM) and then analyzed the pathological changes occurring in decellularized ECM during HF by atomic force microscopy, 2-photon microscopy, high-resolution 3-dimensional image analysis, and computational fluid dynamics simulation. We then performed molecular and functional assays in patient-derived cardiac fibroblasts based on YAP (yes-associated protein)-transcriptional enhanced associate domain (TEAD) mechanosensing activity and collagen contraction assays. The analysis of HF decellularized ECM resulting from ischemic or dilated cardiomyopathy, as well as from mouse infarcted tissue, identified a common pattern of modifications in their 3-dimensional topography. As compared with healthy heart, HF ECM exhibited aligned, flat, and compact fiber bundles, with reduced elasticity and organizational complexity. At the molecular level, RNA sequencing of HF cardiac fibroblasts highlighted the overrepresentation of dysregulated genes involved in ECM organization, or being connected to TGFβ1 (transforming growth factor β1), interleukin-1, TNF-α, and BDNF signaling pathways. Functional tests performed on HF cardiac fibroblasts pointed at mechanosensor YAP as a key player in ECM remodeling in the diseased heart via transcriptional activation of focal adhesion assembly. Finally, in vitro experiments clarified pathological cardiac ECM prevents cell homing, thus providing further hints to identify a possible window of action for cell therapy in cardiac diseases.

CONCLUSIONS

Our multiparametric approach has highlighted repercussions of ECM remodeling on cell homing, cardiac fibroblast activation, and focal adhesion protein expression via hyperactivated YAP signaling during HF.

Colchicine treatment early after infarction attenuates myocardial inflammatory response demonstrated by 14C-methionine imaging and subsequent ventricular remodeling by quantitative gated SPECT

OBJECTIVE

Colchicine has been used as an anti-inflammatory agent and may be cardioprotective after acute myocardial infarction (AMI). We investigated how colchicine administration after AMI affects the myocardial inflammatory response using ¹⁴C-methionine and subsequent ventricular remodeling using single-photon emission computed tomography (SPECT) in a rat model of AMI.

METHODS

The left coronary artery (LCA) was occluded for 30 min followed by reperfusion. ¹⁴C-methionine was injected at 20 min before sacrifice. The LCA was re-occluded at 1 min before sacrifice and ^99mTc-methoxyisobutylisonitrile (^99mTc-MIBI) was injected. Colchicine was administered intraperitoneally from day 1 to the day before ¹⁴C-methionine injection. Dual-tracer autoradiography of the left ventricular short-axis slices was performed. The methionine uptake ratio in an ischemic area was calculated. ^99mTc-MIBI gated SPECT assessed end-diastolic volume (EDV), end-systolic volume (ESV) and left ventricular ejection fraction (LVEF). On Cluster of Differentiation 68 with 4',6-diamidino-2-phenylindole (CD68/DAPI) staining the positive myocardial cell percentage in an ischemic area was calculated.

RESULTS

In control rats, ¹⁴C-methionine uptake ratios on day 3 and 7 were 1.87 ± 0.15 and 1.39 ± 0.12, respectively. With colchicine, the uptake was reduced on days 3 (1.56 ± 0.26, p = 0.042) and 7 (1.23 ± 0.10, p = 0.030). Colchicine treated rats showed smaller EDV, ESV, and higher LVEF compared with control rats. At 8 weeks, those in control rats were 864 ± 115 μL, 620 ± 100 μL, 28.4 ± 2.5%, and in colchicine rats 665 ± 75 μL, 390 ± 97 μL, 42.2 ± 8.5% (p = 0.012, 0.0061, 0.0083), respectively. In control rats, CD68/DAPI positive myocardial cell percentages on days 3 and 7 were 38.4 ± 1.9% and 24.0 ± 2.4%, respectively. With colchicine, the percentages were reduced significantly on both days 3 (31.5 ± 2.0%, p < 0.0001) and 7 (12.0 ± 1.6%, p < 0.0001) as compared with the control.

CONCLUSIONS

Short-term colchicine treatment after AMI attenuated the post-AMI inflammatory response and subsequent ventricular remodeling and dysfunction. ¹⁴C-methionine imaging and gated ^99mTc-MIBI SPECT would be feasible to monitor the effectiveness of anti-inflammatory therapy and left ventricular function.

The Role of False Tendons in Left Ventricular Remodeling and Secondary Mitral Regurgitation After Acute Myocardial Infarction

BACKGROUND

Left ventricular false tendons (LVFT) are common structures visualized on transthoracic echocardiography (TTE). The present study tested the hypothesis that LVFT, via a possible 'constraint' mechanism, attenuate left ventricular (LV) remodeling and secondary mitral regurgitation after acute myocardial infarction.

METHODS

Seventy-one patients admitted to the Coronary Care Unit following an ST-elevation (n = 63) or non-ST-elevation (n = 8) myocardial infarction were analyzed; 29 (41%) had LVFT, and 42 (59%) did not (no-LVFT). All had a TTE and at least 1 follow-up study after revascularization. The χ² analysis, Student's t-test, and Mann Whitney U test were used for the statistical analyses.

RESULTS

The mean age (64 vs. 66 years), left ventricular ejection fraction (LVEF) (41% vs. 39%), left ventricular end-diastolic diameter (LVEDd) index (23 mm/m² for both), and prevalence of ≥ moderate secondary/functional mitral regurgitation (MR) (17% vs. 14%) were similar between the LVFT and no-LVFT groups. At 1-year follow-up, there was no significant difference in chamber remodeling amongst the LVFT versus no-LVFT group when assessed by: 1) ≥ 10% decrease in the relative LVEF (24% vs. 26%; p = 0.83); 2) ≥ 10% increase in the LVEDd index (41% vs. 38%, p = 0.98); and, 3) ≥ 10% increase in the LV mass index (48% vs. 41%, p = 0.68). There was no difference in the prevalence of ≥ moderate secondary/functional MR (17% vs. 12%, p = 0.77). Outcomes remained similar when stratifying by LVFT morphology or ischemic territory.

CONCLUSIONS

In patients with mild to moderate LV dysfunction and normal chamber size, LVFT do not affect the development of LV remodeling or secondary/functional MR post-myocardial infarction.

The protective effect of isosteviol sodium on cardiac function and myocardial remodelling in transverse aortic constriction rat

Pathological hypertrophy contributes to heart failure and there is not quite effective treatment to invert this process. Isosteviol has been shown to protect the heart against ischaemia-reperfusion injury and isoproterenol-induced cardiac hypertrophy, but its effect on pressure overload-induced cardiac hypertrophy is still unknown. Pressure overload induced by transverse aortic constriction (TAC) causes cardiac hypertrophy in rats to mimic the pathological condition in human. This study examined the effects of isosteviol sodium (STVNa) on cardiac hypertrophy by the TAC model and cellular assays in vitro. Cardiac function test, electrocardiogram analysis and histological analysis were conducted. The effects of STVNa on calcium transient of the adult rat ventricular cells and the proliferation of neonatal rat cardiac fibroblasts were also studied in vitro. Cardiac hypertrophy was observed after 3-week TAC while the extensive cardiac dysfunction and electronic remodelling were observed after 9-week TAC. Both STVNa and sildenafil (positive drug) treatment reversed the two process, but STVNa appeared to be more superior in some aspects and did not change calcium transient considerably. STVNa also reversed TAC-induced cardiac fibrosis in vivo and TGF-β1-induced fibroblast proliferation in vitro. Moreover, STVNa, but not sildenafil, reversed impairment of the autonomic nervous system induced by 9-week TAC.

PM2.5 inducing myocardial fibrosis mediated by Ang II/ERK1/2/TGF-β1 signaling pathway in mice model

OBJECTS

To discuss the influence of PM2.5 on myocardial fibrosis and related mechanism.

METHODS

PM2.5 particles were prepared into different concentrations of solution to drip into the mice's trachea twice each week. The mice were divided into five groups, Blank control group (C group), NS control group (J group), high dose group (G group, 10 mg/kg), medium dose group (Z group, 5 mg/kg), and 1ow dose group (D group, 2.5 mg/kg). After 6 weeks, the myocardial fibrosis was observed by HE and Masson staining. The expression of Ang II, ERK1/2, and TGF-β1 was examined by Western Blotting (WB) and Real time PCR (RT-PCR).

RESULTS

The higher dose PM2.5 was administrated, the worse the myocardial fibrosis was in PM2.5 groups. The expression of Ang II, ERK1/2, and TGF-β1 was increased in higher dose groups in protein and mRNA level.

CONCLUSION

1. PM2.5 induced the cardiac fibrosis. 2. PM2.5 dripped into trachea in mice model activated the expression of Ang II, ERK1/2, and TGF-β1. The activation of renin-angiotensin system (RAS) was suggested to participate in the cardiac fibrosis induced by PM2.5.

Role of Speckle Tracking in the Evaluation of Left Ventricular Remodeling After Streptokinase Infusion in Patients with Acute Anterior Myocardial Infarction

Background. Left ventricular (LV) remodeling is an adverse consequence after acute myocardial infarction.Aim. To assess the role of speckle tracking in the evaluation of LV remodeling after streptokinase infusion in patients with acute anterior ST-segment elevation myocardial infarction (STEMI).Material and methods. A total of 200 patients with first acute anterior STEMI received streptokinase as a reperfusion therapy were included. Conventional echocardiography and speckle tracking were performed within 3 days of admission and 3 months later. According to the development of LV remodeling, patients were classified into two groups. Group (I) patients with LV remodeling (60 patients) and group (II) patients without remodeling (140 patients).Results. Patients with LV remodeling had lower global longitudinal (GLS) and circumferential (GCS) strain values (-13.19±4.57 vs. -18.90±4.23 % and -13.16±4.27 vs. -17.16±3.3 %, respectively, p<0.001). GLS cutoff value of >-13.5 was shown to have the best diagnostic accuracy (sensitivity =60.0% & specificity =87.1%) in predicting LV remodeling (AUC 0.816, 95% confidence interval [CI] 0.754-0.877, p<0.001). GCS cutoff value of >-16.21 was shown to have the best diagnostic accuracy (sensitivity =75.0% & specificity =71.4%) in predicting LV remodeling (AUC 0.785, 95%CI 0.719-0.85, p<0.001).Conclusion. Speckle tracking echocardiography either longitudinal or circumferential strain has good sensitivity and specificity in predicting LV remodeling after acute myocardial infarction.

Multiple Intravenous Injections of Valproic Acid-Induced Mesenchymal Stem Cell from Human-Induced Pluripotent Stem Cells Improved Cardiac Function in an Acute Myocardial Infarction Rat Model

Mounting evidence indicates that the mesenchymal stem cell (MSC) injection is safe and efficacious for treating cardiomyopathy; however, there is limited information relating to multiple intravenous injections of human-induced pluripotent stem cell-derived mesenchymal stem cell (hiPSC-MSC) and long-term evaluation of the cardiac function. In the current study, MSC-like cells were derived from human-induced pluripotent stem cells through valproic acid (VPA) induction and continuous cell passages. The derived spindle-like cells expressed MSC-related markers, secreted angiogenic and immune-regulatory factors, and could be induced to experience chondrogenic and adipogenic differentiation. During the induction process, expression of epithelial-to-mesenchymal transition- (EMT-) related gene N-cadherin and vimentin was upregulated to a very high level, and the expression of pluripotency-related genes Sox2 and Oct4 was downregulated or remained unchanged, indicating that VPA initiated EMT by upregulating the expression of EMT promoting genes and downregulating that of pluripotency-related genes. Two and four intravenous hiPSC-MSC injections (10⁶ cells/per injections) were provided, respectively, to model rats one week after acute myocardial infarction (AMI). Cardiac function parameters were dynamically monitored during a 12-week period. Two and four cell injections significantly the improved left ventricular ejection fraction and left ventricular fractional shortening; four-injection markedly stimulated angiogenesis reduced the scar size and cell apoptosis number in the scar area in comparison with that of the untreated control model rats. Although the difference was insignificant, the hiPSC-MSC administration delayed the increase of left ventricular end-diastolic dimension to different extents compared with that of the PBS-injection control. No perceptible immune reaction symptom or hiPSC-MSC-induced tumour formation was found over 12 weeks. Compared with the PBS-injection control, four injections produced better outcome than two injections; as a result, at least four rounds of MSC injections were suggested for AMI treatment.

Signalling pathways linking cysteine cathepsins to adverse cardiac remodelling

Adverse cardiac remodelling clinically manifests as deleterious changes to heart architecture (size, mass and geometry) and function. These changes, which include alterations to ventricular wall thickness, chamber dilation and poor contractility, are important because they progressively drive patients with cardiac disease towards heart failure and are associated with poor prognosis. Cysteine cathepsins contribute to key signalling pathways involved in adverse cardiac remodelling including synthesis and degradation of the cardiac extracellular matrix (ECM), cardiomyocyte hypertrophy, impaired cardiomyocyte contractility and apoptosis. In this review, we highlight the role of cathepsins in these signalling pathways as well as their translational potential as therapeutic targets in cardiac disease.

Long-term prognosis of patients treated by coronary sinus-based percutaneous annuloplasty: single centre experience

AIMS

This study aims to report long-term mortality, echocardiographic, and clinical outcomes of patients receiving treatment for functional mitral regurgitation (FMR) with the Carillon device.

METHODS AND RESULTS

This was a single centre analysis of prospectively collected data from patients treated with the Carillon Mitral Contour System for symptomatic congestive heart failure despite guideline-directed medical therapy, who were included from a single centre from the TITAN II study. All patients presented with New York Heart Association (NYHA) class 2 or greater symptoms, grade 2+ to 4+ FMR, left ventricular enlargement, and reduced ejection fraction. Surviving patients were evaluated for long-term follow-up post-procedure, averaging 6.9 years. Fifteen (15) patients (mean age 72 years, 60% male, 100% NYHA class III or IV, 50% MR grade 3+ or 4+) were treated with the Carillon device. The Kaplan-Meier mortality rate was 40% at 6 years of follow-up. Long-term survival through 6 years was associated with echocardiographic improvement in mitral regurgitation (change in effective regurgitant orifice area in survivors versus non-survivors from baseline to 1 year follow-up, -9.0 ± 5.6 vs. -1.7 ± 1.5, P = 0.02) and clinical status at 12 months (difference in NYHA at 1 year follow-up between survivors versus non-survivors, P = 0. 05) which was sustained throughout follow-up. All patients at 6 year follow-up had ≤2+ MR, with 6 of 7 having 0-1+ MR. Left ventricular end-diastolic volume was reduced from 154.0 ± 65.7 mL at baseline to 104.5 ± 59.2 mL at 6 year follow-up, P = 0.03 in survivors with both measurements.

CONCLUSIONS

Among patients with congestive heart failure treated with the Carillon device, long-term survival is associated with favourable 1 year and sustained improvements in mitral regurgitation, left ventricular volume, ejection fraction, and clinical status.

Chest radiography of contemporary trans-catheter cardiovascular devices: a pictorial essay

There is a plethora of cardiovascular devices used for therapy and monitoring, and newer devices are being introduced constantly. As a result of advancement of medical technology and rapid development of such technology to address unmet needs across cardiovascular care, multiple conditions which were previously treated surgically or with medications now benefit from trans-catheter device-based evaluation and management. Moreover, innovation to existing technology has transformed the structural design of many traditional cardiovascular devices, making them safer and enabling easier deployment within the chest (catheter-based versus surgical). A post-procedure chest radiography (CXR) is often the first routine imaging test ordered in these patients. A CXR is a relatively inexpensive and noninvasive imaging tool, which can be obtained at the patient's bedside if needed. Commonly implanted cardiovascular devices can be quite easily checked for appropriate positioning on routine CXRs. Potential complications associated with mal-positioning of such devices may be life-threatening. Such complications often manifest early on CXRs and may not be readily apparent on clinical examination. Prompt recognition of such abnormal radiographic appearances is critical for timely diagnosis and effective management. Clinicians need to be familiar with new devices in order to assess proper placement and identify complications related to mal-positioning. This pictorial essay aims to describe the radiologic appearances of contemporary cardiovascular devices, review indications for their usage and potential complications, and discuss magnetic resonance imaging (MRI) compatibility.

Increasing heart vascularisation after myocardial infarction using brain natriuretic peptide stimulation of endothelial and WT1+ epicardial cells

Brain natriuretic peptide (BNP) treatment increases heart function and decreases heart dilation after myocardial infarction (MI). Here, we investigated whether part of the cardioprotective effect of BNP in infarcted hearts related to improved neovascularisation. Infarcted mice were treated with saline or BNP for 10 days. BNP treatment increased vascularisation and the number of endothelial cells in all areas of infarcted hearts. Endothelial cell lineage tracing showed that BNP directly stimulated the proliferation of resident endothelial cells via NPR-A binding and p38 MAP kinase activation. BNP also stimulated the proliferation of WT1⁺ epicardium-derived cells but only in the hypoxic area of infarcted hearts. Our results demonstrated that these immature cells have a natural capacity to differentiate into endothelial cells in infarcted hearts. BNP treatment increased their proliferation but not their differentiation capacity. We identified new roles for BNP that hold potential for new therapeutic strategies to improve recovery and clinical outcome after MI.

Combination of serum TIMP-3, CA125, and NT-proBNP in predicting ventricular remodeling in patients with heart failure following acute myocardial infarction

Background

Left ventricular remodeling is the basic pathological mechanism of heart failure following acute myocardial infarction (AMI). Determining sensitive indexes for the early prediction of ventricular remodeling is important for the prevention of heart failure. This study aims to investigate the value of serum TIMP-3, CA125, and NT-proBNP in predicting ventricular remodeling in patients with heart failure following AMI.

Methods

From May 2017 to May 2018, 93 patients with heart failure following AMI were enrolled in the study. The participants were divided into two groups: the ventricular remodeling group (n=51) and the non-ventricular remodeling group (n=42). In addition, 47 healthy subjects who underwent physical examinations in the same period were enrolled as controls. Serum TIMP-3, CA125, and NT-proBNP were measured, in addition to the left ventricular wall thickness (LVWT) and left ventricular mass index (LVMI). The correlation of serum TIMP-3, CA125, and NT-proBNP with the LVWT and LVMI was analyzed, and its value in predicting ventricular remodeling was evaluated.

Results

Serum TIMP-3 level was lower (P<0.05) and CA125 and NT-proBNP levels were higher (P<0.05) in both the ventricular remodeling and non-ventricular remodeling groups compared with the control group. Furthermore, the serum TIMP-3 level was lower in the ventricular remodeling group compared with the non-ventricular remodeling group (P<0.05), while the levels of CA125 and NT-proBNP were higher in the ventricular remodeling group compared with the non-ventricular remodeling group (P<0.05). The serum TIMP-3 level was negatively correlated with the LVWT and LVMI, while serum CA125 and NT-proBNP levels were positively correlated with the LVWT and LVMI, respectively. The area under the receiver operating characteristic curve of the combination of serum TIMP-3, CA125, and NT-proBNP levels in predicting ventricular remodeling was 0.850, and the prediction sensitivity and specificity were 74.51% and 87.71%, respectively.

Conclusions

The combination of serum TIMP-3, CA125, and NT-proBNP can improve the sensitivity and specificity of predicting ventricular remodeling and can aid in the early prevention and treatment of heart failure.

Randomized Trial of Empagliflozin in Nondiabetic Patients With Heart Failure and Reduced Ejection Fraction

BACKGROUND

Large clinical trials established the benefits of sodium-glucose cotransporter 2 inhibitors in patients with diabetes and with heart failure with reduced ejection fraction (HFrEF). The early and significant improvement in clinical outcomes is likely explained by effects beyond a reduction in hyperglycemia.

OBJECTIVES

The purpose of this study was to assess the effect of empagliflozin on left ventricular (LV) function and volumes, functional capacity, and quality of life (QoL) in nondiabetic HFrEF patients.

METHODS

In this double-blind, placebo-controlled trial, nondiabetic HFrEF patients (n = 84) were randomized to empagliflozin 10 mg daily or placebo for 6 months. The primary endpoint was change in LV end-diastolic and -systolic volume assessed by cardiac magnetic resonance. Secondary endpoints included changes in LV mass, LV ejection fraction, peak oxygen consumption in the cardiopulmonary exercise test, 6-min walk test, and quality of life.

RESULTS

Empagliflozin was associated with a significant reduction of LV end-diastolic volume (-25.1 ± 26.0 ml vs. -1.5 ± 25.4 ml for empagliflozin vs. placebo, respectively; p < 0.001) and LV end-systolic volume (-26.6 ± 20.5 ml vs. -0.5 ± 21.9 ml for empagliflozin vs. placebo; p < 0.001). Empagliflozin was associated with reductions in LV mass (-17.8 ± 31.9 g vs. 4.1 ± 13.4 g, for empagliflozin vs. placebo, respectively; p < 0.001) and LV sphericity, and improvements in LV ejection fraction (6.0 ± 4.2 vs. -0.1 ± 3.9; p < 0.001). Patients who received empagliflozin had significant improvements in peak O₂ consumption (1.1 ± 2.6 ml/min/kg vs. -0.5 ± 1.9 ml/min/kg for empagliflozin vs. placebo, respectively; p = 0.017), oxygen uptake efficiency slope (111 ± 267 vs. -145 ± 318; p < 0.001), as well as in 6-min walk test (81 ± 64 m vs. -35 ± 68 m; p < 0.001) and quality of life (Kansas City Cardiomyopathy Questionnaire-12: 21 ± 18 vs. 2 ± 15; p < 0.001).

CONCLUSIONS

Empagliflozin administration to nondiabetic HFrEF patients significantly improves LV volumes, LV mass, LV systolic function, functional capacity, and quality of life when compared with placebo. Our observations strongly support a role for sodium-glucose cotransporter 2 inhibitors in the treatment of HFrEF patients independently of their glycemic status. (Are the "Cardiac Benefits" of Empagliflozin Independent of Its Hypoglycemic Activity? [ATRU-4] [EMPA-TROPISM]; NCT03485222).

Effect of Empagliflozin on Left Ventricular Volumes in Patients With Type 2 Diabetes, or Prediabetes, and Heart Failure With Reduced Ejection Fraction (SUGAR-DM-HF)

BACKGROUND

Sodium-glucose cotransporter 2 inhibitors reduce the risk of heart failure hospitalization and cardiovascular death in patients with heart failure and reduced ejection fraction (HFrEF). However, their effects on cardiac structure and function in HFrEF are uncertain.

METHODS

We designed a multicenter, randomized, double-blind, placebo-controlled trial (the SUGAR-DM-HF trial [Studies of Empagliflozin and Its Cardiovascular, Renal and Metabolic Effects in Patients With Diabetes Mellitus, or Prediabetes, and Heart Failure]) to investigate the cardiac effects of empagliflozin in patients in New York Heart Association functional class II to IV with a left ventricular (LV) ejection fraction ≤40% and type 2 diabetes or prediabetes. Patients were randomly assigned 1:1 to empagliflozin 10 mg once daily or placebo, stratified by age (<65 and ≥65 years) and glycemic status (diabetes or prediabetes). The coprimary outcomes were change from baseline to 36 weeks in LV end-systolic volume indexed to body surface area and LV global longitudinal strain both measured using cardiovascular magnetic resonance. Secondary efficacy outcomes included other cardiovascular magnetic resonance measures (LV end-diastolic volume index, LV ejection fraction), diuretic intensification, symptoms (Kansas City Cardiomyopathy Questionnaire Total Symptom Score, 6-minute walk distance, B-lines on lung ultrasound, and biomarkers (including N-terminal pro-B-type natriuretic peptide).

RESULTS

From April 2018 to August 2019, 105 patients were randomly assigned: mean age 68.7 (SD, 11.1) years, 77 (73.3%) male, 82 (78.1%) diabetes and 23 (21.9%) prediabetes, mean LV ejection fraction 32.5% (9.8%), and 81 (77.1%) New York Heart Association II and 24 (22.9%) New York Heart Association III. Patients received standard treatment for HFrEF. In comparison with placebo, empagliflozin reduced LV end-systolic volume index by 6.0 (95% CI, -10.8 to -1.2) mL/m² (P=0.015). There was no difference in LV global longitudinal strain. Empagliflozin reduced LV end-diastolic volume index by 8.2 (95% CI, -13.7 to -2.6) mL/m² (P=0.0042) and reduced N-terminal pro-B-type natriuretic peptide by 28% (2%-47%), P=0.038. There were no between-group differences in other cardiovascular magnetic resonance measures, diuretic intensification, Kansas City Cardiomyopathy Questionnaire Total Symptom Score, 6-minute walk distance, or B-lines.

CONCLUSIONS

The sodium-glucose cotransporter 2 inhibitor empagliflozin reduced LV volumes in patients with HFrEF and type 2 diabetes or prediabetes. Favorable reverse LV remodeling may be a mechanism by which sodium-glucose cotransporter 2 inhibitors reduce heart failure hospitalization and mortality in HFrEF. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03485092.

Predictive value of early cardiac magnetic resonance imaging functional and geometric indexes for adverse left ventricular remodelling in patients with anterior ST-segment elevation myocardial infarction: A report from the CIRCUS study

BACKGROUND

Postinfarction adverse left ventricular (LV) remodelling is strongly associated with heart failure events. Conicity index, sphericity index and LV global functional index (LVGFI) are new LV remodelling indexes assessed by cardiac magnetic resonance (CMR).

AIM

To assess the predictive value of the new indexes for 1-year adverse LV remodelling in patients with anterior ST-segment elevated myocardial infarction (STEMI).

METHODS

CMR studies were performed in 129 patients with anterior STEMI (58±12 years; 78% men) from the randomized CIRCUS trial (CMR substudy) treated with primary percutaneous coronary intervention and followed for the occurrence of major adverse cardiovascular events (MACE) (death or hospitalization for heart failure). Conicity index, sphericity index, LVGFI, infarct size and microvascular obstruction (MVO) were assessed by CMR performed 5±4 days after coronary reperfusion. Adverse LV remodelling was defined as an increase in LV end-diastolic volume of ≥15% by transthoracic echocardiography at 1 year.

RESULTS

Adverse LV remodelling occurred in 27% of patients at 1 year. Infarct size and MVO were significantly predictive of adverse LV remodelling: odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.05 (P<0.001) and OR 1.12, 95% CI 1.05-1.22 (P<0.001), respectively. Among the newly tested indexes, only LVGFI was significantly predictive of adverse LV remodelling (OR 1.10, 95% CI 1.03-1.16; P=0.001). In multivariable analysis, infarct size remained an independent predictor of adverse LV remodelling at 1 year (OR 1.05, 95% CI 1.02-1.08; P<0.001). LVGFI and infarct size were associated with occurrence of MACE: OR 1.21, 95% CI 1.08-1.37 (P<0.001) and OR 1.02, 95% CI 1.00-1.04 (P=0.018), respectively. Conicity and sphericity indexes were not associated with MACE.

CONCLUSIONS

LVGFI was associated with adverse LV remodelling and MACE 1 year after anterior STEMI.

Predicted Cardiac Hemodynamic Consequences of the Renal Actions of SGLT2i in the DAPA-HF Study Population: A Mathematical Modeling Analysis

The Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF) study demonstrated that dapagliflozin, a sodium-glucose cotransporter-2 inhibitor (SGLT2i), reduced heart failure hospitalization and cardiovascular death in patients with heart failure with reduced ejection fraction (HF-rEF), with and without type 2 diabetes mellitus. Multiple potential mechanisms have been proposed to explain this benefit, which may be multifactorial. This study aimed to quantify the contribution of the known natriuretic/diuretic effects of SGLT2is to changes in cardiac hemodynamics, remodeling, and fluid homeostasis in the setting of HF-rEF. An integrated cardiorenal mathematical model was used to simulate inhibition of SGLT2 and its consequences on cardiac hemodynamics in a virtual population of HF-rEF patients generated by varying model parameters over physiologically plausible ranges and matching to baseline characteristics of individual DAPA-HF trial patients. Cardiovascular responses to placebo and SGLT2i over time were then simulated. The baseline characteristics of the HF-rEF virtual population and DAPA-HF were in good agreement. SGLT2i-induced diuresis and natriuresis that reduced blood volume and interstitial fluid volume, relative to placebo within 14 days. This resulted in decreased left ventricular end-diastolic volume and pressure, indicating reduced cardiac preload. Thereafter, blood volume and interstitial fluid volume again began to accumulate, but pressures and volumes remained shifted lower relative to placebo. After 1 year, left ventricle mass was lower and ejection fraction was higher than placebo. These simulations considered only hemodynamic consequences of the natriuretic/diuretic effects of SGLT2i, as other mechanisms may contribute additional benefits besides those predictions.

Circulating exosomal microRNAs as emerging non-invasive clinical biomarkers in heart failure: Mega bio-roles of a nano bio-particle

Exosomes are nano-sized extracellular vesicles containing a cell-specific biologically active cargo of proteins and genetic materials. Exosomes are constitutively released from almost all cell-types and affect neighboring or distant cells through a complex intercellular exchange of the genetic information and/or regulation of certain gene expressions that change the function and behavior of recipient cells. Those released into body fluids are the major mediators of intercellular communications. The success of the biological functions of exosomes is highly mediated by the effective transfer of microRNAs (miRs). Exosomes secreted by a damaged or diseased heart can exhibit alterations in the miRs' profile that may reflect the cellular origin and (patho)physiological state, as a "signature" or "fingerprint" of the donor cell. It has been shown that the transportation of cardiac-specific miRs in exosomes can be rapidly detected and measured, holding great potential as biomarkers in heart diseases. Currently, the search for new biomarkers of heart diseases remains a large and increasing enterprise. Notably, circulating exosomal miRs (Exo-miRs) have successfully gained huge interests for their diagnostic and prognostic potentials. The present review highlights circulating Exo-miRs explored for diagnosis/prognosis and outcome prediction in patients with heart failure (HF). To this end, we explain the feasibility of exosomes as clinical biomarkers, discuss the priority of circulating Exo-miRs over non-exosomal ones as a biomarker, and then outline reported circulating Exo-miRs having the biomarker function in HF patients, together with their mechanism of action. In conclusion, circulating Exo-miRs represent emerging diagnostic (Exo-miR-92b-5p, Exo-miR-146a, Exo-miR-181c, and Exo-miR-495) and prognostic (Exo-miR-192, Exo-miR-194, Exo-miR-34a, Exo-miR-425, Exo-miR-744) biomarkers for HF.

Sex-Based Differences in Outcomes After Mitral Valve Surgery for Severe Ischemic Mitral Regurgitation: From the Cardiothoracic Surgical Trials Network

OBJECTIVES

This study investigated sex-based differences in outcomes after mitral valve (MV) surgery for severe ischemic mitral regurgitation (SIMR).

BACKGROUND

Whether differences in outcomes exist between men and women after surgery for SIMR remains unknown.

METHODS

Patients enrolled in a randomized trial comparing MV replacement versus MV repair for SIMR were included and followed for 2 years. Endpoints for this analysis included all-cause mortality, major adverse cardiovascular and cerebrovascular events (MACCE) (defined as the composite of death, stroke, hospitalization for heart failure, worsening New York Heart Association functional class or MV re-operation), quality of life (QOL), functional status, and percentage of change in left ventricular end-systolic volume index (LVESVI) from baseline through 2 years.

RESULTS

Of 251 patients enrolled in the trial, 96 (38.2%) were women. Compared with men, women had smaller LV volumes and effective regurgitant orifice areas (EROA) but greater EROA/left ventricular (LV) end-diastolic volume ratios. At 2 years, women had higher rates of all-cause mortality (27.1% vs. 17.4%, respectively; adjusted hazard ratio [adjHR]: 1.85; 95% confidence interval [CI]: 1.05 to 3.26; p = 0.03) and of MACCE (49.0% vs. 38.1%, respectively; adjHR: 1.58; 95% CI: 1.06 to 2.37; p = 0.02). Women also reported worse QOL and functional status at 2 years. There were no significant differences in the percentage of change over 2 years in LVESVI between women and men (adjβ: -10.4; 95% CI: -23.4 to 2.6; p = 0.12).

CONCLUSIONS

Women with SIMR displayed different echocardiographic features and experienced higher mortality and worse QOL after MV surgery than men. There were no significant differences in the degree of reverse LV remodeling between sexes. (Comparing the Effectiveness of Repairing Versus Replacing the Heart's Mitral Valve in People With Severe Chronic Ischemic Mitral Regurgitation [Severe Ischemic Mitral Regurgitation]; NCT00807040).

Targeted Injection of a Truncated Form of Tissue Inhibitor of Metalloproteinase 3 Alters Post-Myocardial Infarction Remodeling

Infarct expansion can occur after myocardial infarction (MI), which leads to adverse left ventricular (LV) remodeling and failure. An imbalance between matrix metalloproteinase (MMP) induction and tissue inhibitors of MMPs (TIMPs) can accelerate this process. Past studies have shown different biologic effects of TIMP-3, which may depend upon specific domains within the TIMP-3 molecule. This study tested the hypothesis that differential effects of direct myocardial injections of either a full-length recombinant TIMP-3 (F-TIMP-3) or a truncated form encompassing the N-terminal region (N-TIMP-3) could be identified post-MI. MI was induced in pigs that were randomized for MI injections (30 mg) and received targeted injections within the MI region of F-TIMP-3 (n = 8), N-TIMP-3 (n = 9), or saline injection (MI-only, n = 11). At 14 days post-MI, LV ejection fraction fell post-MI but remained higher in both TIMP-3 groups. Tumor necrosis factor and interleukin-10 mRNA increased by over 10-fold in the MI-only and N-TIMP-3 groups but were reduced with F-TIMP-3 at this post-MI time point. Direct MI injection of either a full-length or truncated form of TIMP-3 is sufficient to favorably alter the course of post-MI remodeling. The functional and differential relevance of TIMP-3 domains has been established in vivo since the TIMP-3 constructs demonstrated different MMP/cytokine expression profiles. These translational studies identify a unique and more specific therapeutic strategy to alter the course of LV remodeling and dysfunction after MI. SIGNIFICANCE STATEMENT: Using different formulations of tissue inhibitor of matrix metalloproteinase-3 (TIMP-3), when injected into the myocardial infarction (MI) region, slowed the progression of indices of left ventricular (LV) failure, suggesting that the N terminus of TIMP-3 is sufficient to attenuate early adverse functional events post-MI. Injections of full-length recombinant TIMP-3, but not of the N-terminal region of TIMP-3, reduced relative indices of inflammation at the mRNA level, suggesting that the C-terminal region affects other biological pathways. These unique proof-of-concept studies demonstrate the feasibility of using recombinant small molecules to selectively interrupt adverse LV remodeling post-MI.

miR-145 attenuates cardiac fibrosis through the AKT/GSK-3β/β-catenin signaling pathway by directly targeting SOX9 in fibroblasts

Myocardial infarction (MI) will inevitably result in cardiac fibrosis. In this study, we investigated the effect of microRNA-145 (miR-145) and transcription factor sex-determining region Y box 9 (SOX9) in the production of cardiac fibrosis induced by MI. MI rat models were established by left anterior descending coronary artery (LAD) occlusion. Four weeks after LAD, the cardiac fibrosis level was assessed by Masson's trichrome staining. Cardiac fibroblasts (CFs) exposed to hypoxia were used to simulate MI-induced fibrosis. Flow cytometry, cell counting kit-8, and transwell assays were used to examine changes in CF apoptosis, proliferation, and migration, respectively. miR-145 expression was measured by quantitative real-time polymerase chain reaction. Immunofluorescence and Western blot analysis were performed to determine the relative expression of proteins. In comparison to the sham-operated group, the expression of miR-145 was significantly downregulated in the infarction peripheral area, whereas, SOX9 was upregulated. In the infarcted heart, the overexpression of miR-145 significantly ameliorated cardiac fibrosis and cardiac function, and there was a negative correlation between miR-145 and SOX9 expressions in hypoxic CFs in vitro. In addition, SOX9 was verified to be a functional target of miR-145. Overexpression of miR-145 or inhibition of SOX9 decreased CF proliferation, migration, and fibrosis, but augmented their apoptotic rate. Moreover, the upregulation of miR-145 or suppression of SOX9 inhibited AKT and β-catenin signaling in hypoxic CFs. Taken together, this study highlights a potential treatment for cardiac fibrosis through the targeted regulation of SOX9 by miR-145, and our findings indicate that miR-145 exerts anti-fibrotic effects in MI via the negative regulation of SOX9 and its downstream AKT/GSK-3β/β-catenin pathways.

β-adrenergic activation may promote myosin light chain kinase degradation through calpain in pressure overload-induced cardiac hypertrophy: β-adrenergic activation results in MLCK degradation

BACKGROUND

β-adrenergic activation is able to exacerbate cardiac hypertrophy. Myosin light chain kinase (MLCK) and its phosphorylated substrate, phospho-myosin light chain 2 (p-MLC2), play vital roles in regulating cardiac hypertrophy. However, it is not yet clear whether there is a relationship between β-adrenergic activation and MLCK in the progression of cardiac hypertrophy. Therefore, we explored this relationship and the underlying mechanisms in this work.

METHODS

Cardiac hypertrophy and cardiomyocyte hypertrophy were induced by pressure overload and isoproterenol (ISO) stimulation, respectively. Echocardiography, histological analysis, immunofluorescence and qRT-PCR were used to confirm the successful establishment of the models. A β-blocker (metoprolol) and a calpain inhibitor (calpeptin) were administered to inhibit β-adrenergic activity in rats and calpain in cardiomyocytes, respectively. The protein expression levels of MLCK, myosin light chain 2 (MLC2), p-MLC2, myosin phosphatase 2 (MYPT2), calmodulin (CaM) and calpain were measured using western blotting. A cleavage assay was performed to assess the degradation of recombinant human MLCK by recombinant human calpain.

RESULTS

The β-blocker alleviated cardiac hypertrophy and dysfunction, increased MLCK and MLC2 phosphorylation and decreased calpain expression in pressure overload-induced cardiac hypertrophy. Additionally, the calpain inhibitor calpeptin attenuated cardiomyocyte hypertrophy, upregulated MLCK and p-MLC2 and reduced MLCK degradation in ISO-induced cardiomyocyte hypertrophy. Recombinant human calpain degraded recombinant human MLCK in vitro in concentration- and time-dependent manners, and this degradation was inhibited by the calpain inhibitor calpeptin.

CONCLUSION

Our study suggested that β-adrenergic activation may promote the degradation of MLCK through calpain in pressure overload-induced cardiac hypertrophy.