Search Results (52)

Myocardial viability assessment plays a critical role in the clinical management of patients with ischemic heart disease, particularly in guiding revascularization decisions. Various non-invasive imaging modalities have been developed and refined to evaluate viable myocardium, each offering unique insights into myocardial perfusion, metabolism, and contractile function. This review examines the comparative strengths and limitations of key imaging techniques. Understanding the pathophysiological basis and diagnostic capabilities of these modalities enables clinicians to tailor viability assessments to individual patient profiles, ultimately enhancing decision-making and optimizing outcomes in ischemic cardiomyopathy. Full article

Background/Objectives: Although cardiac resynchronization therapy (CRT) plays an established role in the management of heart failure, a significant proportion of patients do not respond despite appropriate candidate selection. The optimization of CRT pacing is one strategy to enhance response. Fusion pacing algorithms aim to synchronize intrinsic right ventricular (RV) conduction with paced left ventricular (LV) activation, resulting in a more physiological ventricular depolarization pattern. This approach may improve electrical synchrony and enhance left ventricular contraction compared to conventional simultaneous biventricular pacing. The aim of this study was to compare the acute, beat-to-beat effects of standard biventricular pacing versus fusion pacing on myocardial function, using both conventional and speckle-tracking echocardiography in heart failure patients with left bundle branch block (LBBB). Methods: In total, 27 heart failure patients (21 men and 6 women) with reduced ejection fraction (EF < 35%), left bundle branch block (QRS > 150 ms), and newly implanted CRT-D systems (Abbott) underwent echocardiographic assessment immediately after device implantation. Echocardiographic parameters—including left atrial strain, left ventricular strain, TAPSE, mitral and tricuspid valve function, and cardiac output—were measured at 5 min intervals under three different pacing conditions: pacing off, simultaneous biventricular pacing, and fusion pacing using Abbott’s SyncAV^® algorithm. Results: In our study, CRT led to a significant shortening of the QRS duration from 169 ± 19 ms at baseline to 131 ± 17 ms with standard biventricular pacing, and further to 118 ± 16 ms with fusion pacing (p < 0.05). Despite the electrical improvement, no significant changes were observed in global longitudinal strain (GLS: −9.15 vs. −9.39 vs. −9.13; p = NS), left ventricular stroke volume (67.5 mL vs. 68.4 mL vs. 68.5 mL; p = NS), or left atrial parameters including strain, area, and ejection fraction. However, fusion pacing was associated with more homogeneous segmental strain patterns, improved aortic valve closure time, and enhanced right ventricular function as reflected by tissue Doppler-derived S’. Conclusions: Immediate QRS narrowing observed in CRT patients—particularly with fusion pacing optimization—is associated with a more homogeneous pattern of left ventricular contractility and improvements in selected measures of mechanical synchrony. However, these acute electrical changes do not translate into immediate improvements in stroke volume, global LV strain, or left atrial function. Longer-term follow-up is needed to determine whether the electrical benefits of CRT, especially with fusion pacing, lead to meaningful hemodynamic improvements. Full article

Heart failure with preserved ejection fraction (HFpEF) represents nearly half of all heart failure cases and remains diagnostically challenging due to its heterogeneous pathophysiology and often subtle myocardial dysfunction. Conventional echocardiographic parameters, such as left ventricular ejection fraction (LVEF) and the left atrial volume index (LAVI), frequently fail to detect early functional changes. Advanced echocardiographic techniques have emerged as valuable tools for early diagnosis and risk stratification. Global Longitudinal Strain (GLS) allows for the identification of subclinical systolic dysfunction, even with preserved LVEF. Left Atrial Strain (LAS), particularly reservoir and pump strain, provides sensitive markers of diastolic function and elevated filling pressures, offering additional diagnostic and prognostic insights. Myocardial Work (MW), through non-invasive pressure–strain loops, enables load-independent assessment of contractility, while Right Ventricular Free Wall Longitudinal Strain (RVFWLS) captures early right heart involvement, often present in advanced HFpEF. The integration of these advanced parameters can enhance diagnostic precision and guide personalized treatment strategies. This review highlights the current evidence and clinical applications of strain-based imaging in HFpEF, underscoring the importance of a multiparametric, pathophysiology-oriented approach in heart failure evaluation. Full article

Sodium–glucose cotransporter 2 inhibitors (iSGLT2) have become the fourth pillar of the medical treatment for heart failure with reduced ejection fraction (HFrEF). However, the mechanisms of action of iSGLT2 remain poorly understood. The effectiveness of combined ARNI and iSGLT2 therapy in left ventricular (LV) remodeling is still under study. We aim to investigate the effects of ARNI + iSGLT2 combination therapy in patients affected by HFrEF in terms of ventricular remodeling using speckle tracking echocardiography (STE). In this observational study, 136 patients with HFrEF taking ARNI were enrolled. All patients were evaluated at baseline (before iSGLT2), at 3 months and at 12 months from the beginning of iSGLT2 therapy. Echocardiographic parameters, including STE analysis and volumetric and LV contractile function indices, were collected at the three timepoints. The objectives were (1) to evaluate the effects of ARNI + iSGLT2 combination therapy on ultrasound (US) measurements; (2) to evaluate the effects on the variation of laboratory data indicative of HF (NT-pro-BNP); and (3) to evaluate the medium-long term impact of the ARNI + iSGLT2 combination therapy in terms of major cardiovascular events (MACVE). After only three months of combined ARNI + iSGLT2 therapy, we reported a significant improvement in ventricular and atrial volumetric indices, systolic function indices and myocardial deformation parameters assessed by STE. We also reported a significant decrease in NTproBNP levels. This trend was confirmed at 12 months follow-up. Furthermore, narrowing down the analysis to patients who were already treated with ARNI when they started taking iSGLT2, we reported similar results in the improvement of US parameters and NTproBNP levels. Our study has shown that the ARNI + iSGLT2 combination therapy leads to a clinical improvement and positive ventricular remodeling. Even the single introduction of additional iSGLT-2 in HFrEF patients on an otherwise optimized therapy resulted in a significant improvement in US and laboratory variables. The results of our study suggest implementing iSGLT-2 therapy as soon as possible, as the structural and functional cardiac improvements achieved by these drugs are achieved in the short term and maintained in the long term. Full article

Feline hyperthyroidism is the most frequent endocrinopathy in adult and senior cats, frequently leading to cardiac changes characterised by a hypertrophic cardiomyopathy (HCM) phenotype, which may partially reverse with appropriate treatment. However, the structural and molecular alterations in the myocardium can persist and closely resemble those observed in hypertrophic cardiomyopathy. Despite this clinical overlap, protein expression patterns in the hearts of hyperthyroid cats remain poorly understood. This study aimed to evaluate the myocardial expression of desmin, a key contractile protein, as well as calreticulin and interleukin-10 proteins involved in cardiac remodelling and response to injury. Left ventricular samples were obtained from 16 hyperthyroid cats, 12 cats with HCM, and 10 healthy controls. Immunohistochemical staining was performed to assess the expression patterns of the selected proteins. Our findings revealed that, despite median left ventricular dimensions not being significantly different from ones observed in healthy animals, cats with hyperthyroidism exhibited similar alterations in desmin and interleukin-10 expression to those seen in HCM-affected cats. These changes were associated with cardiomyocyte degeneration and coronary artery narrowing, suggesting a shared pathway of myocardial injury independent of the primary disease. Full article

Background/Objectives: Dobutamine stress echocardiography (DSE) is a non-invasive diagnostic technique commonly employed in routine clinical practice to identify coronary artery disease. Emerging echocardiographic methods, including strain and strain rate imaging, quantify alterations in myocardial contractility and may improve the diagnostic accuracy of DSE. The main aim of this study was to assess the correlation between visual interpretation and longitudinal strain during dobutamine stress echocardiography. Methods: Our study was observational and was conducted at the Cardiology Clinic of the University Clinical Center of the Republic of Srpska. It included 70 patients who underwent dobutamine stress echocardiography. The patients were divided into two groups (diagnostic and viable study). A visual assessment of segmental contractility of the left ventricle was performed, as well as an assessment of contractility with longitudinal strain (LS) during the test. Results: The median baseline LS of segments without impaired contractility in the diagnostic study was −20% (−21 to −18) and, at the peak of the test, −22% (−23 to −21), which was statistically significant (p < 0.05). The median baseline LS in the segments with impaired contractility was −17% (−18 to −16) and, at the peak of the test, −13% (−15 to −12), which was statistically significant (p < 0.05). In the viability study, the average baseline LS in the segments with improved contractility was −8% (−11 to −7) and, at the peak of the test, −14% (−17 to −13), which was statistically significant (p < 0.05). The average baseline LS in the segments without improved contractility was −6% (−5 to −7) and, at the peak of the test, −2% (−3 to −0), which was statistically significant (p < 0.05). Conclusions: Our study indicates a good correlation between a visual assessment of left ventricular segment contractility and longitudinal strain during dobutamine stress echocardiography. Full article

Cardiovascular diseases are the leading cause of morbidity and mortality worldwide, underscoring the urgent need for novel therapeutic targets and strategies. The kinase MARK4 (MAP (microtubule-associated proteins)/microtubule affinity-regulating kinase 4) regulates microtubule-associated proteins pivotal for cell polarity, protein stability, and intracellular signaling. Animal models of heart failure revealed elevated MARK4 levels, which correlated with impaired cardiac contractility. However, the involvement of MARK4 and its potential as a molecular drug target has not yet been explored in the myocardium of cardiovascular patients. We investigated the MARK4 mRNA expression in human myocardial biopsies of 152 high-risk cardiovascular patients undergoing cardiac surgery. Comprehensive echocardiography as well as testing for sleep-disordered breathing (SDB), a critical comorbidity in heart failure, were assessed preoperatively. We observed a substantial upregulation of myocardial MARK4 expression in patients with impaired cardiac contractility, resulting in an inverse correlation with the left ventricular ejection fraction. Myocardial MARK4 expression also correlated with echocardiographic E/e’, a central parameter of diastolic dysfunction. Mechanistically, our analyses revealed that MARK4 expression increases in SDB and under hypoxic conditions, as evidenced by significant correlations between myocardial MARK4 expression and factors like mean oxygen saturation, time with oxygen saturation below 90%, and the oxygen desaturation index. Multivariable regression analysis revealed that both left ventricular ejection fraction and mean oxygen saturation were independently associated with dysregulated MARK4 levels, even when controlling for important clinical covariables as potential confounders. Taken together, our findings demonstrate that MARK4 expression is highly increased in the myocardium of cardiovascular high-risk patients, suggesting it is a potential molecular target against cardiovascular diseases. Full article

Cardiac computed tomography (CT) has rapidly advanced, becoming an invaluable tool for diagnosing and prognosticating various cardiovascular diseases. While echocardiography and cardiac magnetic resonance imaging (CMR) remain the gold standards for myocardial assessment, modern CT technologies offer enhanced spatial resolution, making it an essential tool in clinical practice. Cardiac CT has expanded beyond coronary artery disease evaluation, now playing a key role in assessing cardiomyopathies and structural heart diseases. Innovations like photon-counting CT enable precise estimation of myocardial extracellular volume, facilitating the detection of infiltrative disorders and myocardial fibrosis. Additionally, CT-based myocardial strain analysis allows for the classification of impaired myocardial contractility, while quantifying cardiac volumes and function remains crucial in cardiomyopathy evaluation. This review explores the emerging role of cardiac CT in cardiomyopathy phenotyping, emphasizing recent technological advancements. Full article

The prevalence of heart failure, driven significantly by ischemic heart disease, continues to rise globally. Myocardial viability—the potential ability of dysfunctional myocardium to recover contractile function after revascularization—remains an ongoing key area of research in managing ischemic cardiomyopathy. Advances in imaging modalities, including PET/SPECT, cardiac MRI, and dobutamine stress echocardiography, have enabled identification of viable myocardium that can potentially predict their functional recovery following revascularization. Despite these advances, recent evidence from major trials questions the routine reliance on viability testing for revascularization guidance. These studies found a limited correlation between myocardial viability and improved outcomes in key metrics including mortality. Furthermore, they highlighted the effectiveness of guideline-directed medical therapy in improving left ventricular function independent of revascularization. This narrative review explores the concept of myocardial viability, its assessment through contemporary imaging techniques, its clinical utility in decision making for revascularization, and future directions. Full article

Background and Objectives: Cardiac involvement in COVID-19 has been confirmed during the acute stage of the infection. However, the prevalence and spectrum of post-infectious cardiac dysfunction remain incompletely clarified. The objective of our study was to evaluate the frequency of echocardiographic changes 2 years after hospitalization for moderate and severe COVID-19 in patients with no previously known cardiac pathology. Material and Methods: We conducted a retrospective cohort study analyzing severity markers of COVID-19 infection and echocardiographic parameters assessed ≥2 years after the acute illness, based on recent guideline recommended algorithm for echocardiographic diagnostic of left ventricular (LV) dysfunction. Results: The study included 50 Caucasian patients, 60% male, 54% aged < 65 years, and 32% with severe forms of the disease. The primary comorbidities were hypertension, obesity, and diabetes. COVID-19 severity correlated with the computed tomography (CT) lung lesion score and a neutrophil-to-lymphocyte ratio >6 but was not associated with post-COVID-19 echocardiographic changes. Left ventricular ejection fraction (LVEF) was reduced in only 18% of cases, but global longitudinal strain (GLS) impairment was observed in 46% of patients, contributing to the LV systolic subclinical dysfunction in 61%. Impaired LV diastolic disfunction with normal pressure filling was present in 30.61% of cases and with elevated pressure 10.2%. Conclusions: COVID-19 is an independent predictive factor for GLS impairment, which can indicate myocardial contractile dysfunction, even in patients with asymptomatic heart disease. This underscores the importance of regular echocardiographic monitoring for patients recovering from moderate to severe COVID-19. Full article

Hypertrophic cardiomyopathy (HCM) is often characterized by augmented cardiac contractility, which frequently remains undetectable in its early stages. Emerging evidence suggests that hypercontractility is linked to mitochondrial defects that develop early in HCM progression. However, imaging markers for identifying these early alterations in myocardial function are lacking. We used cardiac magnetic resonance feature tracking (CMR-FT) to assess myocardial strain in a Mybpc3-knockin (KI) mouse model that mimicked human HCM. While homozygous (HOM) mice exhibited cardiac hypertrophy, heterozygous (HET) mice represented an early, asymptomatic stage of HCM. To explore mitochondrial contributions to hypercontractility, we evaluated mitochondrial integrity via scanning electron microscopy (SEM) and correlated these findings with strain abnormalities. Young HET female, but not male mice exhibited significant torsion abnormalities (p = 0.02), reduced left ventricular global longitudinal strain (LVGLS, p = 0.009), and impaired right ventricular global longitudinal strain (RVGLS, p = 0.035) compared to the controls. Strain abnormalities correlated strongly with mitochondrial morphological alterations, including changes in volume and area distribution (R > 0.7). Abnormal myocardial strain patterns, including torsion and GLS, serve as early markers of HCM and are closely associated with underlying mitochondrial dysfunction. The HET Mybpc3-KI HCM model provides important insights into the initial stages of HCM progression, highlighting strain abnormalities and sex-specific differences to enhance early diagnosis and therapeutic strategies. Full article

Background/Objectives: Diffuse myocardial fibrosis and altered deformation are relevant prognostic factors in aortic stenosis (AS) patients. The aim of this exploratory study was to investigate the relationship between myocardial strain, and myocardial extracellular volume (ECV) in patients with severe AS with a photon-counting detector (PCD)-CT. Methods: We retrospectively included 77 patients with severe AS undergoing PCD-CT imaging for transcatheter aortic valve replacement (TAVR) planning between January 2022 and May 2024 with a protocol including a non-contrast cardiac scan, an ECG-gated helical coronary CT angiography (CCTA), and a cardiac late enhancement scan. Myocardial strain was assessed with feature tracking from CCTA and ECV was calculated from spectral cardiac late enhancement scans. Results: Patients with cardiac amyloidosis (n = 4) exhibited significantly higher median mid-myocardial ECV (48.2% versus 25.5%, p = 0.048) but no significant differences in strain values (p > 0.05). Patients with prior myocardial infarction (n = 6) had reduced median global longitudinal strain values (−9.1% versus −21.7%, p < 0.001) but no significant differences in global mid-myocardial ECV (p > 0.05). Significant correlations were identified between the global longitudinal, circumferential, and radial strains and the CT-derived left ventricular ejection fraction (EF) (all, p < 0.001). Patients with low-flow, low-gradient AS and reduced EF exhibited lower median global longitudinal strain values compared with those with high-gradient AS (−15.2% versus −25.8%, p < 0.001). In these patients, the baso-apical mid-myocardial ECV gradient correlated with GLS values (R = 0.28, p = 0.02). Conclusions: In patients undergoing PCD-CT for TAVR planning, ECV and GLS may enable us to detect patients with cardiac amyloidosis and reduced myocardial contractility Full article

Impaired contractility after myocardial infarction (MI) causes cardiogenic shock. MARK4 activity impairs contractility post-MI by increasing α-tubulin detyrosination. We assessed the impact of naringenin, a small-molecule MARK4 inhibitor, on contractility post-MI. Naringenin (Nar) was encapsulated in PEG-PCL to augment bioavailability. Wistar rats were randomized to receive either MI + micellized naringenin (0.3 mg/kg) [MI-NarMic], MI + naringenin (0.3 mg/kg) in 1% DMSO [MI-NarDMSO], MI + empty micelle [MI-Mic], MI alone [MI-Untreated], or no MI [Sham]. MI was induced via left anterior descending artery ligation. Invasive hemodynamics with pressure–volume catheterization, cardiomyocyte contractility, and ventricular protein abundance were assessed one day post-MI. A total of 45 rats underwent hemodynamic assessment. MI-NarMic rats demonstrated decreased α-tubulin detyrosination relative to MI-Untreated rats (p < 0.05). Myocytes isolated from peri-infarct tissue had increased contraction and relaxation velocities in MI-NarMic versus MI-Untreated rats (both p < 0.0001). MI-NarMic rats had higher ejection fractions than MI-Mic and MI-Untreated rats (63 ± 3% v. 48 ± 5% vs. 39 ± 4%, p < 0.05) and similar levels to Sham (61 ± 1%, p = 0.97) and MI-NarDMSO (54 ± 5%) rats (p > 0.05). MI-Nar rats had greater stroke work and lower end-diastolic pressure and tau than MI-Untreated rats (all p < 0.05). Micellized naringenin is a translatable agent with the potential to rescue hemodynamics post-MI by inhibiting MARK4 and mitigating myocardial α-tubulin detyrosination. Full article

Radiation therapy (RT) is widely used to treat thoracic cancers but carries a risk of radiation-induced heart disease (RIHD). This study aimed to detect early markers of RIHD using machine learning (ML) techniques and cardiac MRI in a rat model. SS.BN3 consomic rats, which have a more subtle RIHD phenotype compared to Dahl salt-sensitive (SS) rats, were treated with localized cardiac RT or sham at 10 weeks of age. Cardiac MRI was performed 8 and 10 weeks post-treatment to assess global and regional cardiac function. ML algorithms were applied to differentiate sham-treated and irradiated rats based on early changes in myocardial function. Despite normal global left ventricular ejection fraction in both groups, strain analysis showed significant reductions in the anteroseptal and anterolateral segments of irradiated rats. Gradient boosting achieved an F1 score of 0.94 and an ROC value of 0.95, while random forest showed an accuracy of 88%. These findings suggest that ML, combined with cardiac MRI, can effectively detect early preclinical changes in RIHD, particularly alterations in regional myocardial contractility, highlighting the potential of these techniques for early detection and monitoring of radiation-induced cardiac dysfunction. Full article

Background: Cardiovascular diseases rank as the top global cause of mortality, particularly acute myocardial infarction (MI). MI arises from the blockage of a coronary artery, which disrupts blood flow and results in tissue death. Among therapeutic approaches, bioactives from medicinal plants emerge as promising for the development of new medicines. Objectives: This study explored the effects of naringenin (NAR 100 mg/kg), a flavonoid found in citrus fruits, in normotensive (NTR) and spontaneously hypertensive (SHR) rats, both subjected to isoproterenol (ISO 85 mg/kg)-induced MI. Results: Post-treatment assessments indicated that NAR reduced blood pressure and minimized clot formation, particularly notable in the SHR group, which helps mitigate damage related to hypertension and ISO exposure. Additionally, NAR effectively restored KCl-induced contractility in the aortas of both NTR and SHR groups. NAR treatment reduced reduced glutathione (GSH) and lipid hydroperoxides (LOOH) values and recovered the activity of the antioxidant enzymes catalase (CAT) and glutathione-s-transferase (GST) in NTR groups. Moreover, myocardial damage assessed through histological analyses was reduced in groups treated with NAR. Conclusions: The results highlight significant pathophysiological differences between the groups, suggesting that NAR has protective potential against ISO-induced cardiac damage, warranting further investigation into its protective effects and mechanisms. Full article