Papillary Muscle Of Left Ventricle Research Articles

Left Ventricular Papillary Muscle: Anatomy, Pathophysiology, and Multimodal Evaluation.

As an integral part of the mitral valve apparatus, the left ventricle papillary muscle (PM) controls mitral valve closure during systole and participates in the ejection process during left ventricular systole. Mitral regurgitation (MR) is the most immediate and predominant result when the PM is structurally or functionally abnormal. However, dysfunction of the PM is easily underestimated or overlooked in clinical interventions for MR-related diseases. Therefore, adequate recognition of PM dysfunction and PM-derived MR is critical. In this review, we systematically describe the normal anatomical variations in the PM and the pathophysiology of PM dysfunction-related diseases and summarize the commonly used parameters and the advantages and disadvantages of various noninvasive imaging modalities for the structural and functional assessment of the PM.

Ablation of premature ventricle contraction arising from papillary muscle without intracardiac echo using point-by-point mapping

Abstract Background Catheter radiofrequency ablation (RFA) of ventricular arrhythmias (VAs) arising from the left ventricle's papillary muscles (PM) has been associated with inconsistent results due to difficulties in 3D reconstruction of this intraventricular structure. The use of intracardiac echo-guided ablation allows for the 2D visualisation of the PM and the guiding of ablation catheter. Cryo energy allows stable contact with the target structure during ablation. These two techniques have been shown to increase the success rate of ablation (77% reported - 1) but don’t allow the construction of the 3D map of papillary muscle with activation during PVC. Using a combination of point-by-point mapping (PbP) along with "fast anatomical mapping" (FAM) (Carto® 3 System) allows 3D reconstruction of the PM geometry with activation. These may increase the accuracy of PVC origin targeting. Aim This study aims to assess the feasibility and success rate of RFA of PVC arising from the papillary muscles of the left ventricle. Methods and results We retrospectively analysed 214 patients treated with RFA for PVCs in two institutions. PVC arose from PM in 12(5.6%) cases (65±20 years old; 42% males; 33% with ejection fraction>50%; 8.3% antero-lateral PM). Initial detailed FAM of the left ventricle was performed using PVC pattern matching via transaortic or transmitral approach. Then, all points with preexcitation to QRS onset were copied from FAM into the new PbP map. That automatically created the geometry of PM with an activation map inside the LV shell. Irrigated high power (50 W) RFA was performed at the site of earliest activation at the PM shell. The acute success rate was 75% (n=9) without complications. PVC recurrence at 12-month follow-up was 11% (n=1 out of 9). Conclusions RFA of PVC arising from papillary muscles using point-by-point mapping is feasible and associated with a success rate comparable to the previously reported one when intracardiac echo-guided ablation is used.

Morphological Assessment and Possible Clinical Implications of the Left Ventricle Papillary Muscles. Study in a Colombian Population Sample

Morphological Assessment and Possible Clinical Implications of the Left Ventricle Papillary Muscles. Study in a Colombian Population Sample

Abstract 9841: Outcomes Following Biventricular Repair of Atrioventricular Septal Defect With a Single Left Ventricular Papillary Muscle

Introduction: In patients with atrioventricular septal defect (AVSD) with single papillary muscle attachments in the left ventricle (LV), the left AV valve (LAVV) is at risk for suboptimal repair. This study aimed to evaluate outcomes following repair of AVSD with single LV papillary muscle attachments and to identify preoperative predictors of postoperative LAVV outcomes. Methods: All patients with AVSD and anatomically or functionally single LV papillary muscle who underwent biventricular repair at our institution from 07/01/2000 - 07/01/2020 were retrospectively reviewed. Univariate analysis was used to identify associations between patient demographics, preoperative echocardiographic measures, and surgical characteristics with the degree of LAVV stenosis or regurgitation postoperatively and the need for reintervention on the LAVV. Results: Of 38 patients included, nearly all (97%) were repaired with no or partial closure of the LAVV cleft. Freedom from LAVV reintervention was 91% and 84% at 1 and 3 years. Five patients (13%) required reintervention on the LAVV with a median time to reintervention of 3.3 months post-AVSD repair; indication was LAVV regurgitation for four of the five patients. Preoperative LAVV regurgitation > mild was associated with an increased risk for LAVV reintervention (p= 0.02). At discharge, 63% of patients had > mild LAVV regurgitation and 5% had > mild LAVV stenosis. At most recent follow-up, 32% had > mild LAVV regurgitation and 12% had > mild LAVV stenosis. Patients with younger age at repair and preoperative AV valve index <0.67 had significantly increased risk of > mild LAVV regurgitation at discharge (p=0.01 and p=0.04, respectively), however this did not persist at most recent follow-up. More pronounced unbalance of the AVSD was not associated with postoperative LAVV stenosis. Conclusions: Despite concern for repair in patients with AVSD and single papillary muscle attachments, surgical outcomes are favorable with low risk for reintervention. Risk of LAVV stenosis is low when repair of LAVV cleft is modified. Preoperative LAVV regurgitation, younger age at repair, and more pronounced unbalance of the AVSD predicted early postoperative LAVV regurgitation, with improvement over time.

Optimal catheter-tissue contact value for ablation of ventricular arrythmias originating from the left ventricular papillary muscles

Abstract Funding Acknowledgements Type of funding sources: None. Background Good catheter-tissue contact is mandatory to create effective ablation lesions. The minimal contact force (CF) value for successful ablation of arrhythmias originating from the left ventricle (LV) was reported at the 8-10 g level, however, optimal CF values for ablation of arrhythmias arising from papillary muscles (PM) are not known. Purpose To determine optimal CF value for ablation of arrhythmias from LV PM. Methods Twenty-four consecutive patients (mean age 57,9 ± 11,9 years, 16 males) who from May 2017 to June 2020 underwent ablation of premature ventricular complexes (PVC) originating from LV PM were included. The primary endpoints were an acute procedural success (total elimination of PVC) and long-term success (median 27 months). Ablation was performed with the use of the CARTO electro-anatomical system and intracardiac echocardiography (ICE). Results Acute success – complete abolition of PVC, was obtained in 23 (96%) patients. The fluoroscopy time was 3,9 ± 3,5 min and the procedure duration was 114,8 ± 38 min. The mean number of applications was 8,74 ± 6,78 and the mean application time - 518,5 ± 437,25 sec. The mean CF during successful ablations was 3,1 ± 1,5 g, with 3 ± 1,1 g and 3,18 ± 1,8 g for anterolateral and posteromedial PM, respectively (p= 0,809975). The mean CF during one unsuccessful ablation was 3 g. At control Holter ECG, the mean PVC burden in all patients was reduced from 28,36 ± 14,48 % to 2,42 ± 2 %: in the anterolateral PM group from 18 ± 8 % to 2,6 ± 2 % (p= 0,005415) and in the posteromedial PM group - from 34,8 ± 13,7 % to 1,7 ± 1,3 % (p= 0,012694). During long-term follow-up (median 27, IQR 17-34) there was one recurrence among 23 patients who had acutely successful procedures. Conclusion The values of CF for successful ablation of PVC originating from LV PM are lower than those for ablation in other parts of LV. The values slightly exceeding 3 g seem to be sufficient to achieve ablation success.

Three dimensional modeling of atrioventricular valves provides predictive guides for optimal choice of prosthesis.

Inaccuracies in intraoperative and preoperative measurements and estimations may lead to adverse outcomes such as patient-prosthesis mismatch. We aim to measure the relation between different dimensions of the atrioventricular valve complex in explanted porcine heart models. After a detailed physical morphology study, a cast of the explanted heart models was made using silicon-based materials. Digital models were obtained from three-dimensional scanning of the casts, showing the measured annulopapillary distance was 2.50 ± 0.18 cm, and 2.75 ± 0.36 cm for anterior and posterior papillary muscles of left ventricle, respectively. There was a significant linear association between the mitral annular circumference to anterior–posterior distance (p = 0.003, 95% CI 0.78–3.06), mitral annular circumference to interpapillary distance (p = 0.009, 95% CI 0.38–2.20), anterior–posterior distance to interpapillary distance (p = 0.02, 95% CI 0.10–0.78). Anterior–posterior distance appeared to be the most important predictor of mitral annular circumference compared to other measured distances. The mean length of the perpendicular distance of the tricuspid annulus, a, was 2.65 ± 0.54 cm; b was 1.77 ± 0.60 cm, and c was 3.06 ± 0.55 cm. Distance c was the most significant predictor for tricuspid annular circumference (p = 0.006, 95% CI 0.28–2.84). The anterior–posterior distance measured by three-dimensional scanning can safely be used to predict the annular circumference of the mitral valve. For the tricuspid valve, the strongest predictor for the circumference is the c-distance. Other measurements made from the positively correlated parameters may be extrapolated to their respective correlated parameters. They can aid surgeons in selecting the optimal prosthesis for the patients and improve procedural planning.

Algorithm for diagnosis and typing of ALCAPA syndrome

ALCAPA syndrome was characterized by anomalous origin of left coronary artery from pulmonary artery. Its clinical presentation is varied and although it is an anomaly of congenital origin, it is not exclusive to pediatric ages. Its epidemiological documentation is difficult. We aimed to make the non-invasive diagnosis of the ALCAPA syndrome and its variants. An observational, prospective and cross-sectional study was conducted with 31 patients with a positive echocardiographic diagnosis of ALCAPA syndrome at Pediatric Cardio Center “William Soler” from 2005 to 2018. The variables with significance for diagnosis were the echocardiographic visualization of the anomalous connection and the reversed flow in the left coronary artery. The variables with significance for typing were age at diagnosis, ischemia in the electrocardiogram, echocardiographic visualization of left ventricle papillary muscles fibrosis, presence of severe mitral regurgitation, left ventricle spheroidal remodeling, left ventricle ejection fraction, left ventricular end-diastolic volume index, and left ventricular end-diastolic diameter index. An algorithm integrated by various diagnostic modalities associated with echocardiography as a tool for the detection of ALCAPA was developed. The documentation of the diagnostic and classificatory aspects of the syndrome is possible by detecting echocardiographic elements in conjunction with electrocardiographic and radiological aspects.

Endogenous asymmetric dimethylarginine accumulation precipitates the cardiac and mitochondrial dysfunctions in type 1 diabetic rats

Myocardial mitochondrial function and biogenesis are suppressed in diabetes, but the mechanisms are unclear. Increasing evidence suggests that asymmetric dimethylarginine (ADMA) is associated with diabetic cardiovascular complications. This study was to determine whether endogenous ADMA accumulation contributes to cardiac and mitochondrial dysfunctions of diabetic rats and elucidate the potential mechanisms. Diabetic rat was induced by single intraperitoneal injection of streptozotocin (50 mg/kg). N-acetylcysteine was given (250 mg/kg/d) by gavage for 12w. Cardiac function was detected by echocardiography. Left ventricle papillary muscles were isolated to examine myocardial contractility. Myocardial ATP and mitochondrial DNA contents were measured to evaluate mitochondrial function and biogenesis. Endogenous ADMA accumulation was augmented resulting in decreased nitric oxide (NO) production and increased oxidative stress, suggesting NO synthase (NOS) uncoupling in the myocardium of T1DM rats compared with control rats. ADMA augmentation was associated with cardiac and mitochondrial dysfunctions along with myocardial uncoupling protein-2 (UCP2) upregulation and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) downregulation in T1DM rats. Exogenous ADMA could directly inhibit myocardial contractility, mitochondrial function and biogenesis in parallel with decreasing NO content and PGC-1α expression while increasing oxidative stress and UCP2 expression in papillary muscles and cardiomyocytes. Treatment with antioxidant N-acetylcysteine, also an inhibitor of NOS uncoupling, either ameliorated ADMA-associated cardiac and mitochondrial dysfunctions or reversed ADMA-induced NO reduction and oxidative stress enhance in vivo and in vitro. These results indicate that myocardial ADMA accumulation precipitates cardiac and mitochondrial dysfunctions in T1DM rats. The underlying mechanism may be related to NOS uncoupling, resulting in NO reduction and oxidative stress increment, ultimate PGC-1α down-regulation and UCP2 up-regulation.

Isolated obesity resistance condition or associated with aerobic exercise training does not promote cardiac impairment.

Mechanisms involved in cardiac function and calcium (Ca2+) handling in obese-resistant (OR) rats are still poorly determined. We tested the hypothesis that unsaturated high-fat diet (HFD) promotes myocardial dysfunction in OR rats, which it is related to Ca2+ handling. In addition, we questioned whether exercise training (ET) becomes a therapeutic strategy. Male Wistar rats (n=80) were randomized to standard or HFD diets for 20 weeks. The rats were redistributed for the absence or presence of ET and OR: control (C; n=12), control + ET (CET; n=14), obese-resistant (OR; n=9), and obese-resistant + ET (ORET; n=10). Trained rats were subjected to aerobic training protocol with progressive intensity (55-70% of the maximum running speed) and duration (15 to 60 min/day) for 12 weeks. Nutritional, metabolic, and cardiovascular parameters were determined. Cardiac function and Ca2+ handling tests were performed in isolated left ventricle (LV) papillary muscle. OR rats showed cardiac atrophy with reduced collagen levels, but there was myocardial dysfunction. ET was efficient in improving most parameters of body composition. However, the mechanical properties and Ca2+ handling from isolated papillary muscle were similar among groups. Aerobic ET does not promote morphological and cardiac functional adaptation under the condition of OR.

Late Gadolinium Enhancement of Left Ventricular Papillary Muscles in Patients with Mitral Regurgitation.

ObjectiveArrhythmogenic mitral valve prolapse (MVP) is an important cause of sudden cardiac death characterized by fibrosis of the papillary muscles or left ventricle (LV) wall, and an association between late gadolinium enhancement (LGE) of the LV papillary muscles and ventricular arrhythmia in MVP has been reported. However, LGE of the papillary muscles may be observed in other causes of mitral regurgitation, and it is not limited to patients with MVP. This study was to evaluate the association of LGE of the LV papillary muscles or ventricular wall on cardiac magnetic resonance imaging (CMR) and ventricular arrhythmia in patients with mitral regurgitation.Materials and MethodsThis study included 88 patients (mean age ± standard deviation, 58.3 ± 12.0 years; male, 42%) with mitral regurgitation who underwent CMR. They were allocated to the MVP (n = 43) and non-MVP (n = 45) groups, and their LGE images on CMR, clinical characteristics, echocardiographic findings, and presence of arrhythmia were compared.ResultsLV myocardial wall enhancement was more frequent in the MVP group than in the non-MVP group (28% vs. 11%, p = 0.046). Papillary muscle enhancement was observed in 7 (7.9%) patients. Of the 43 patients with MVP, 15 (34.8%) showed LGE in the papillary muscles or LV myocardium, including 12 (27.9%) with LV myocardial wall enhancement and 4 (9.3%) with papillary muscle enhancement. One patient with bilateral diffuse papillary muscle enhancement experienced sudden cardiac arrest due to ventricular fibrillation. Univariable logistic regression analysis showed that high systolic blood pressure (BP; odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01–1.09; p = 0.027) and ventricular arrhythmia (OR, 6.84; 95% CI, 1.29–36.19; p = 0.024) were significantly associated with LGE of the papillary muscles.ConclusionLGE of the papillary muscles was present not only in patients with MVP, but also in patients with other etiologies of mitral regurgitation, and it was associated with high systolic BP and ventricular arrhythmia. Papillary muscle enhancement on CMR should not be overlooked.

Deep Learning-based Automated Segmentation of Left Ventricular Trabeculations and Myocardium on Cardiac MR Images: A Feasibility Study.

To develop and evaluate a complete deep learning pipeline that allows fully automated end-diastolic left ventricle (LV) cardiac MRI segmentation, including trabeculations and automatic quality control of the predicted segmentation. This multicenter retrospective study includes training, validation, and testing datasets of 272, 27, and 150 cardiac MR images, respectively, collected between 2012 and 2018. The reference standard was the manual segmentation of four LV anatomic structures performed on end-diastolic short-axis cine cardiac MRI: LV trabeculations, LV myocardium, LV papillary muscles, and the LV blood cavity. The automatic pipeline was composed of five steps with a DenseNet architecture. Intraobserver agreement, interobserver agreement, and interaction time were recorded. The analysis includes the correlation between the manual and automated segmentation, a reproducibility comparison, and Bland-Altman plots. The automated method achieved mean Dice coefficients of 0.96 ± 0.01 (standard deviation) for LV blood cavity, 0.89 ± 0.03 for LV myocardium, and 0.62 ± 0.08 for LV trabeculation (mean absolute error, 3.63 g ± 3.4). Automatic quantification of LV end-diastolic volume, LV myocardium mass, LV trabeculation, and trabeculation mass-to-total myocardial mass (TMM) ratio showed a significant correlation with the manual measures (r = 0.99, 0.99, 0.90, and 0.83, respectively; all P < .01). On a subset of 48 patients, the mean Dice value for LV trabeculation was 0.63 ± 0.10 or higher compared with the human interobserver (0.44 ± 0.09; P < .01) and intraobserver measures (0.58 ± 0.09; P < .01). Automatic quantification of the trabeculation mass-to-TMM ratio had a higher correlation (0.92) compared with the intra- and interobserver measures (0.74 and 0.39, respectively; both P < .01). Automated deep learning framework can achieve reproducible and quality-controlled segmentation of cardiac trabeculations, outperforming inter- and intraobserver analyses.Supplemental material is available for this article.© RSNA, 2020.

Myocardial Dysfunction in Cirrhotic Cardiomyopathy is Associated with Alterations of Phospholamban Phosphorylation and IL-6 Levels

Decreased cardiac contractility has been observed in cirrhosis, but the mechanisms that initiate and maintain cardiac dysfunction are not entirely understood. We test the hypothesis that cirrhotic cardiomyopathy is related to deterioration of myocardial contractility due to alterations in calcium-handling proteins expression. In addition, we evaluated whether cardiac pro-inflammatory cytokine levels are associated with this process. Cirrhosis was induced by thioacetamide (TAA, 100mg/kg/i.p., twice weekly for eight weeks). The myocardial performance was evaluated in isolated left ventricle papillary muscles under basal conditions and after inotropic challenge. The cardiac calcium handling protein expression was detected by Western blotting. Cardiac TNF-α and IL-6 levels were measured by ELISA. Thioacetamide induced liver cirrhosis, which was associated with cirrhotic cardiomyopathy characterized by invivo left ventricular diastolic and systolic dysfunction as well as cardiac hypertrophy. Invitro baseline myocardial contractility was lower in cirrhosis. Also, myocardial responsiveness to post-rest contraction stimulus was declined. Protein expression for RYR2, SERCA2, NCX, pPBL Ser16 and L-type calcium channel was quantitatively unchanged; however, pPBL Thr17 was significantly lower while IL-6 was higher. Our study demonstrates that cirrhotic cardiomyopathy is associated with decreased cardiac contractility with alteration of phospholamban phosphorylation in association with higher cardiac pro-inflammatory IL-6 levels. These findings provided molecular and functional insights about the effects of liver cirrhosis on cardiac function.

Relationship between papillary muscles abnormalities and apparently unexplained infero-lateral T-wave inversion in athletes

Abstract Aims To evaluate by cardiac magnetic resonance (CMR) if left ventricle papillary muscle abnormalities, such as hypertrophy and abnormal location, may be the anatomo-functional substrates responsible for TWI inversion in lateral or infero-lateral leads in otherwise healthy athletes. Methods We included competitive athletes with TWI in lateral or infero-lateral leads in the absence of cardiac diseases detected by CMR. The control population included healthy athletes with normal ECG, matched for age and gender. We compared thickness, volume (both absolute and relative to the cardiac mass) and position of the papillary muscles between cases and controls. Results We included 53 athletes with apparently unexplained TWI in the lateral or infero-lateral leads (median age 20 years (17–42), 86.8% males) and 53 athletes with no TWI matched for age and gender. 4 patients (7.6%) had family history for cardiomyopathy or sudden cardiac death. Athletes with TWI showed more hypertrophic papillary muscles compared to controls, with statistically significant difference in diameter, area and volume (p&amp;lt;0.01). The median ratio between the papillary muscles and the left ventricular mass was 4.4% among athletes with TWI versus 3% among those without TWI (p&amp;lt;0.001). Papillary muscles showed apical displacement in 47% of cases, compared to 17% in the control group (p=0.001). Conclusions Idiopathic TWI in lateral or infero-lateral leads is associated with left ventricle papillary muscle hypertrophy and their apical displacement detected by CMR. The comprehension of clinical and prognostic significance of papillary muscle abnormalities responsible for these ventricular repolarization alterations requires further studies. Example Funding Acknowledgement Type of funding source: None

Multipolar mapping for catheter ablation of premature ventricular complexes originating from papillary muscles in the structurally normal heart: a case series

BackgroundPrevious studies on radiofrequency catheter ablation of premature ventricular complexes (PVCs) arising from the left ventricle (LV) papillary muscles (PM) show a modest procedural success rate with higher recurrence rate. Our study sought to explore the utility of using a multipolar mapping with a steerable linear duodecapolar catheter for ablating the PM PVCs.MethodsDetailed endocardial multipolar mapping was performed using a steerable linear duodecapolar catheter in 6 consecutive PM PVCs patients with structurally normal heart. The clinical features and procedural data as well as success rate were analysed.ResultsLV endocardial electroanatomic mapping was performed in all patients via a retrograde aortic approach using a duodecapolar mapping catheter. All patients displayed a PVC burden with 16.2 ± 5.4%. Duodecapolar catheter mapping demonstrated highly efficiency with an average procedure time (95.8 ± 7.4 min) and fluoroscopy time (14.2 ± 1.5 min). The mean number of ablation applications points was 6.8 ± 1.9 with an average overall ablation duration of 6.1 ± 3.0 min. The values of earliest activation time during mapping using duodecapolar catheter were 37.8 ± 7.2 ms. All patients demonstrated acute successful ablation, and the PVC burden in all patients after an average follow-up of 8.5 ± 2.0 months was only 0.7%. There were no complications during the procedures and after follow-up.ConclusionsMapping and ablation of PM PVCs using a duodecapolar catheter facilitated the identification of earliest activation potentials and pace mapping, and demonstrated a high success rate during follow-up.

1045 T1-mapping and CMR feature tracking in mitral valve prolapse

Abstract BACKGROUND Several studies suggest that mitral valve prolapse (MVP) can be related to sudden cardiac death, owing to sustained ventricular arrhythmias (VAs). In patients with sudden cardiac death and complex VAs, a high percentage of either left ventricle (LV) papillary muscle fibrosis or inferobasal fibrosis has been described using cardiac magnetic resonance (CMR) with late gadolinium enhancement technique (LGE). However, LGE presents several technical limitations and requires contrast agent administration. Thanks to T1 mapping (T1-map) and feature tracking (FT) techniques, CMR may identify myocardial fibrosis and deformation abnormalities respectively. We sought to demonstrate that, in patients with MVP, T1 map can accurately identify the presence of myocardial fibrosis which, being related to myocardial stiffness, is associated to abnormal deformation indexes at CMR FT strain evaluation. METHODS Consecutive patientswith indication to mitral valve surgery for severe mitral regurgitation due to mitral valve prolapse were prospectively enrolled. CMR including Modified Look-Locker (MOLLI) sequences for T1 mapping was performed in each patient. In addition, CMR FT analysis of steady state free precession (SSFP) cine images was performed to obtain 2D global and segmental circumferential and radial strains. RESULTS 70 consecutive patients (age: 59 ± 12) were successfully evaluated with CMR. T1 native values were significantly higher in the basal and mid LV inferolateral wall compared to the remote myocardium (1074 ± 67 vs 1046 ± 40 msec, p&amp;lt; 0.001). Moreover, the average radial and circumferential strains of the basal and mid LV inferolateral were significantly reduced compared to those of the remote myocardium (21.1 ± 10.4 and -12.8 ± 5.6 vs 31.6 ± 9.1 and -17.3 ± 3.6 respectively, p &amp;lt; 0.001). CONCLUSIONS In patients with MVP and severe mitral regurgitation native T1 values of the LV inferolateral are higher as compared to remote myocardium and associated with reduced circumferential and radial strains. T1 mapping and CMR FT strain may be used as tools for the early identification of tissue changes in the LV inferolateral myocardial segment. Further studies are needed to evaluate if these changes are able to predict LGE development and are associated with higher risk for VAs

The activity of transforming growth factor-β in young age with marfanoid habitus

According to contemporary views, hereditary connective tissue disorders divided classified Marfan syndrome, Loeys-Dietz’s, Ehlers-Danlos syndrome, the primary mitral valve prolapse. It is known that the fibrillinopaty, which include the Marfan syndrome and Loeys-Dietz’s is characterized by activation of TGF-β signaling pathway. With high le vels of TGF-β attributed most of these clinical manifestations these diseases – aneurysm of the aorta, arahnodaktylya, duralectasy. Assessment of the activity of TGF-β in persons with marfanoid habitus has not previously been studied.&#x0D; Materials and methods. As part of this work, surveyed 70 people: 61 patients young age (median age of 20.1 ± 2.1 years), among which 36 boys and 25 girls and 9 men with verified diagnosis Marfan syndrome (median age 27.9 ± 9.3 years). All survey performed Echocardiography with a targeted search of small anomalies of heart.&#x0D; Results. Correlation analysis showed a direct and reliable connection between arahnodaktylya and concentration of TGF-β1 in serum (r = 0.4, p = 0.05). For young people with signs of marfanoid habitus are characterized by reliably a higher concentration in the serum of both isoforms of TGF-β. Excess of threshold levels of TGF-β1 revealed at 20% of the core group and not found at all in the control (p &lt; 0.05). Among persons with exceedances of threshold values for at least one faction of the TGF-β patients with signs of marfanoid habitus met almost three times more often than in the group with normal values of TGF-β (p = 0.01, χ2 = 5.58). In the group of persons with marfanoid habitus and increases TGF-β are detected more frequently such as atrial septal aneurysm, false chord left ventricle papillary muscles, incremental, deflection of shutters of the mitral valve in 1-2 mm, asymmetry tricuspid aortic valve.

HAND1 loss-of-function within the embryonic myocardium reveals survivable congenital cardiac defects and adult heart failure.

To examine the role of the basic Helix-loop-Helix (bHLH) transcription factor HAND1 in embryonic and adult myocardium. Hand1 is expressed within the cardiomyocytes of the left ventricle (LV) and myocardial cuff between embryonic days (E) 9.5-13.5. Hand gene dosage plays an important role in ventricular morphology and the contribution of Hand1 to congenital heart defects requires further interrogation. Conditional ablation of Hand1 was carried out using either Nkx2.5 knockin Cre (Nkx2.5Cre) or α-myosin heavy chain Cre (αMhc-Cre) driver. Interrogation of transcriptome data via ingenuity pathway analysis reveals several gene regulatory pathways disrupted including translation and cardiac hypertrophy-related pathways. Embryo and adult hearts were subjected to histological, functional, and molecular analyses. Myocardial deletion of Hand1 results in morphological defects that include cardiac conduction system defects, survivable interventricular septal defects, and abnormal LV papillary muscles (PMs). Resulting Hand1 conditional mutants are born at Mendelian frequencies; but the morphological alterations acquired during cardiac development result in, the mice developing diastolic heart failure. Collectively, these data reveal that HAND1 contributes to the morphogenic patterning and maturation of cardiomyocytes during embryogenesis and although survivable, indicates a role for Hand1 within the developing conduction system and PM development.

Study of Numbers of Papillary Muscles in Left Ventricle of Fetal Hearts of Gestational Age from 14 to 40 Weeks

Study of Numbers of Papillary Muscles in Left Ventricle of Fetal Hearts of Gestational Age from 14 to 40 Weeks

Percutaneous cryoablation for papillary muscle ventricular arrhythmias after failed radiofrequency catheter ablation.

Catheter ablation of ventricular arrhythmias (VA) from the papillary muscles (PM) is challenging due to limited catheter stability and contact on the PMs with their anatomic complexity and mobility. This study aimed to evaluate the effectiveness of cryoablation as an adjunctive therapy for PM VAs when radiofrequency (RF) ablation has failed. We evaluated a retrospective series of patients who underwent cryoablation for PM VAs when RF ablation had failed. The decision to switch to cryoablation was at the operator's discretion when intracardiac echocardiography (ICE) suggested that cryoablation might be more effective in achieving catheter stability and energy delivery. Sixteen patients underwent cryoablation of PM VAs between 2014 and 2016 after RF ablation was unsuccessful. VAs originated from the anterolateral left ventricle (LV) PM (six patients), posterolateral LV PM (six patients), and right ventricle PM (four patients). VAs were predominantly frequent premature ventricular complexes (PVCs); however, patients with sustained ventricular tachycardia and PVC-triggered VF were also represented. Fifteen of the 16 patients were treated with cryoablation; in one patient, a procedural complication with retrograde aortic access precluded treatment. In all patients treated with cryoablation, contact and stability was confirmed with ICE to be superior to the RF catheter, and there was acute and long-term elimination of VAs. Cryoablation is a useful adjunctive therapy in ablation of PM VAs, providing excellent procedural outcomes even when RF ablation has failed. Cryoablation catheters are less maneuverable than RF ablation catheters and care is required to avoid complications.

Comparative Study Between the Papillary Muscles of the Right Ventricle and the Left Ventricle Papillary Muscles

Abstract We used formalinized heart dissection obtained from forensic laboratory in Constanta, analyzing the papillary muscles and their tendon chordae. We studied at the papillary muscles the number of forms that could be in single or multiple muscular bodies, encountering more than five body muscles in a papillary muscle group. We measured using caliper graduated in millimeters, the height of each papillary muscle body (from the base to its upper end) and its thickness at the base and at its upper extremity. Chordae tendon we examined in terms of their origin and number at the level of each papillary muscle, the dimensions (length and thickness), orientation and how they end at the atrioventricular valves. We noted the presence of „false”chordae tendineae, which were disposed between the papillary muscle and the ventricular wall. The results were compared with data in the literature that I had the opportunity to consult