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Various experimental mouse models are extensively used to research human diseases, including atrial fibrillation, the most common cardiac rhythm disorder. Despite this, there are no comprehensive mathematical models that describe the complex behavior of the action potential and [Ca2+]i transients in mouse atrial myocytes. Here, we develop a novel compartmentalized mathematical model of mouse atrial myocytes that combines the action potential, [Ca2+]i dynamics, and β-adrenergic signaling cascade for a subpopulation of right atrial myocytes with developed transverse-axial tubule system. The model consists of three compartments related to β-adrenergic signaling (caveolae, extracaveolae, and cytosol) and employs local control of Ca2+ release. It also simulates ionic mechanisms of action potential generation and describes atrial-specific Ca2+ handling as well as frequency dependences of the action potential and [Ca2+]i transients. The model showed that the T-type Ca2+ current significantly affects the later stage of the action potential, with little effect on [Ca2+]i transients. The block of the small-conductance Ca2+-activated K+ current leads to a prolongation of the action potential at high intracellular Ca2+. Simulation results obtained from the atrial model cells were compared with those from ventricular myocytes. The developed model represents a useful tool to study complex electrical properties in the mouse atria and could be applied to enhance the understanding of atrial physiology and arrhythmogenesis. NEW & NOTEWORTHY A new compartmentalized mathematical model of mouse right atrial myocytes was developed. The model simulated action potential and Ca2+ dynamics at baseline and after stimulation of the β-adrenergic signaling system. Simulations showed that the T-type Ca2+ current markedly prolonged the later stage of atrial action potential repolarization, with a minor effect on [Ca2+]i transients. The small-conductance Ca2+-activated K+ current block resulted in prolongation of the action potential only at the relatively high intracellular Ca2+.

Speckle tracking echocardiography (STE), and more recently, cardiovascular magnetic resonance myocardial feature tracking (CMR-FT) provides insight into all phases of atrial function. The aim of our study was to compare all phases of RA strain using CMR-FT and STE and also assess the relationship between RA and LA strain. A total of 61 healthy volunteers with mean age of 45 ± 13 years had adequate tracking for analysis on CMR-FT and 2D-STE. Females had larger RA reservoir strain (39 ± 15% vs. 32 ± 13%, p = 0.046) and conduit strain (26 ± 12% vs. 20 ± 9%, p = 0.03) when compared to males, but was not the case with booster strain (14 ± 7% vs. 12 ± 6%, p = 0.45). In comparison with STE derived strain, the RA reservoir and conduit strain were not significantly different between CMR-FT and the three echocardiography gating methods (p > 0.05 for all). Noticeably, there were no significant differences in strain and strain rate between RA and LA function using CMR-FT (p > 0.05 for all). RA strain and strain rate using CMR-FT had fair and good intra- and inter-observer reproducibility and had superior reproducibility compared to STE derived strain.

Sex-specific outcome data following myocardial infarction (MI) are inconclusive with some evidence suggesting association of female sex and increased major adverse cardiac events (MACE). Since mechanistic principles remain elusive, we aimed to quantify the underlying phenotype using cardiovascular magnetic resonance (CMR) quantitative deformation imaging and tissue characterisation.In total, 795 ST-elevation MI patients underwent post-interventional CMR imaging. Feature-tracking (CMR-FT) was performed in a blinded core-laboratory. Left ventricular function was quantified using ejection fraction (LVEF) and global longitudinal/circumferential/radial strains (GLS/GCS/GRS). Left atrial function was assessed by reservoir (εs), conduit (εe) and booster-pump strains (εa). Tissue characterisation included infarct size, microvascular obstruction and area at risk. Primary endpoint was the occurrence of MACE within 1 year.Female sex was associated with increased MACE (HR 1.96, 95% CI 1.13-3.42, p = 0.017) but not independently of baseline confounders (p = 0.526) with women being older, more often diabetic and hypertensive (p 0.001) and of higher Killip-class (p = 0.010). Tissue characterisation was similar between sexes. Women showed impaired atrial (εs p = 0.011, εe p 0.001) but increased systolic ventricular mechanics (GLS p = 0.001, LVEF p = 0.048). While atrial and ventricular function predicted MACE in men only LV GLS and GCS were associated with MACE in women irrespective of confounders (GLS p = 0.036, GCS p = 0.04).In men ventricular systolic contractility is impaired and volume assessments precisely stratify elevated risks. In contrast, women experience reduced atrial but increased ventricular systolic strain. This may reflect ventricular diastolic failure with systolic compensation, which is independently associated with MACE adding incremental value to sex-specific prognosis evaluation.

OBJECTIVES Atrial function in Fontan patients is unknown. Our goal was to report the relationship of atrial function with the cardiac index and atrial function and clinical outcome through longer follow-up periods. METHODS Twelve patients were followed up for over 20 years after their first Fontan operation. Atrial function, including the expansion index, atrial ejection fraction, passive ejection fraction and active ejection fraction, was examined using cardiac computed tomography. The relationship of atrial function with the cardiac index and failing Fontan patients was analysed. RESULTS Twelve Fontan patients were included. The median follow-up period after the first Fontan operation was 27 (range, 21-33) years, and the median age of those examined was 33.5 (range, 24-60) years. There were 6 male patients (50%). The cardiac index showed a significant positive correlation with the expansion index (P = 0.02), the atrial ejection fraction (P = 0.035), and the active ejection fraction (P = 0.013). The expansion index (39.2 ± 19.6 vs 64.1 ± 3.9), atrial ejection fraction (26.6 ± 10.9 vs 39.0 ± 1.5%), booster pump (15.6 ± 9.0 vs 31.3 ± 3.5) and cardiac index (2.1 ± 0.3 vs 2.5 ± 0.2 L/min/m2) were significantly lower in patients with a history of arrhythmia than in patients without a history of arrhythmia (P CONCLUSIONS Patients with atrial arrhythmia and signs of Fontan failure have lower atrial function than those without.

The left atrium is a dynamic chamber with peculiar characteristics. Stressors and disease mechanisms may deeply modify its structure and function, leading to left atrial remodelling and disease. Left atrial disease is a predictor of poor outcomes. It may be a consequence of left ventricular systolic and diastolic dysfunction and neurohormonal and inflammatory activation and/or actively contribute to the progression and clinical course of heart failure through multiple mechanisms such as left ventricular filling and development of atrial fibrillation and subsequent embolic events. There is growing evidence that therapy may improve left atrial function and reverse left atrial remodelling. Whether this translates into changes in patient's prognosis is still unknown. In this review we report current data about changes in left atrial size and function across different stages of development and progression of heart failure. At each stage, drug therapies, lifestyle interventions and procedures have been associated with improvement in left atrial structure and function, namely a reduction in left atrial volume and/or an improvement in left atrial strain function, a process that can be defined as left atrial reverse remodelling and, in some cases, this has been associated with improvement in clinical outcomes. Further evidence is still needed mainly with respect of the possible role of left atrial reverse remodelling as an independent mechanism affecting the patient's clinical course and as regards better standardization of clinically meaningful changes in left atrial measurements. Summarizing current evidence, this review may be the basis for further studies.

Background: The Cystic fibrosis (CF) is an autosomal recessive inherited disease. The mutation of the transmembrane conductance regulator gene causes the mucous to be more viscous. Due to the respiratory organ complications, changes in heart structure and function often occur. The right ventricle (RV) is frequently affected, but the left ventricle (LV) can be impaired as well. There are no data on atrial function and structure in this group of patients. Aim: We investigated the left and right atrial function and mechanics in CF patients, and their predictive value regarding the mortality. Methods: A total of 82 CF patients (18 of them died until the June 2019, and 64 survived, 2 Groups) and 32 healthy subjects, who underwent TTE between the October 2012 and December 2016, were included in this retrospective study. Patients with heart, liver, kidney, lung or malignant disease were excluded, as well as those with inadequate images (n=15). All non-echocardiographic parameters were gained from the subjects’ histories. The echo-images assessment was performed “offline” on an EchoPAC 201 Program by a single blinded examiner. Statistical analysis was done in IBM SPSS 25.0 Program by applying adequate tests. Results: The three groups did not differ in age and sex. Non-survivors had lower body mass index (BMI) than the other two groups. The control group had greater LV diameters, but the relative wall thickness (RWT) was greater in CF groups. The diastolic dysfunction was more frequent in CF non-survivor group than in others, whereas systolic function did not differ. LA volume index (LAVi), E/e’ and E/A had significantly greater values in non-survivors. RV parameters was similar between the groups. The values of tricuspid annular plane systolic excursion (TAPSE) was reduced significantly in CF patient groups. CF patients had greater RAVi and PAP than the controls. The global LA strain (total, positive and negative) did not show any differences among the groups. The global LA early diastolic strain rate was diminished significantly in CF patients. The total strain and positive strain values in 4-chamber view were significantly decreased in the groups with patients, as was the LA early diastolic strain rate also. Strain and strain rate was without significance between the groups in 2-chamber view. The RA strain and strain rate parameters showed no difference. Two parameters were predictors of mortality in CF patients: LAVi and RAVi. Conclusion: CF patients had larger atria, especially the non-survivors, than the controls. CF patients had decreased conduit and reservoir function. RA function did not differ from the controls. LAVi and RAVi were predictors of a fatal outcome. This work highlights the importance of the atrial assessment in CF patients., Hintergrund: Die zystische Fibrose ist eine autosomal-rezessive vererbte Erkrankung. Die Mutation des transmembrane conductance regulator Gens verursacht den dickflüssigen Mukus. Aufgrund der respiratorischen Komplikationen, kann es zu Veränderungen in der Funktion und Struktur des Herzens vorkommen. Die rechte Kammer ist oft betroffen, aber auch die linke Kammer kann Veränderungen aufweisen. Es liegen in der Literatur keine Daten zur atrialen Funktion und Struktur bei diesen Patienten vor. Ziel: Das Ziel der Arbeit ist die Einschätzung der linken und der rechten atrialen Funktion und Mechanik bei CF Patienten und dessen Wertes bezüglich der Mortalität. Methoden: 82 CF Patienten (18 bis June 2019 gestorben und 64 überlebt, 2 Gruppen) und 32 Probanden, die einer TTE Untersuchung in Zeitspanne von Oktober 2012 und Dezember 2016 unterzogen wurden, wurden in der retrospektiven Studie eingeschlossen. Patienten mit Herz-, Leber-, Nieren-, Lungen- und Krebserkrankungen sowie jene mit inadäquaten Aufnahmen (n=15) wurden ausgeschlossen. Alle nicht echokardiographischen Parameter wurden aus den Patientenakten erhoben. Die Auswertung der echokardiographischen Aufnahmen erfolgte „offline“ mittels EchoPAC 201 Programm, von einem verblindeten Untersucher. Statistische Analyse erfolgte mittels IBM SPSS 25.0 Programms und der entsprechenden Tests. Ergebnisse: Die 3 Gruppen ähnelten sich im Alter und Geschlecht. Die nicht überlebende Gruppe wies einen niedrigeren BMI als die anderen Gruppen auf. LV Diameter war größer in der Kontrollgruppe, aber RWT war niedriger. Diastolische Dysfunktion war häufiger in CF nicht-überlebende Gruppe als in den anderen zwei, aber hinsichtlich der systolischen Dysfunktion gab es keinen Unterschied. LAVi, E/e‘ und E/A waren höher in der nicht-überlebende Gruppe. RV Parameter zeigten keinen Unterschied zwischen den Gruppen, bis auf TAPSE, das kleiner in CF Gruppen war. RAVi und PAP waren größer bei CF Patienten als bei Kontrollen. Die globale LA Strain (total, positiv und negativ) zeigte keinen Unterschied zwischen den Gruppen. Die globale LA früh diastolische Strain Rate war niedriger bei CF Patienten. Die totale und positive LA Strain und LA früh-diastolische Strain Rate im 4-Kammer Blick waren niedriger in CF Gruppen. Wir fanden keinen Unterschied in Strain und Strain Rate zwischen den Gruppen im 2- Kammer Blick und für den rechten Vorhof. 2 Parameter stellen prognostische Faktoren für die Mortalität bei CF Patienten dar: LAVi und RAVi. Schlussfolgerung: Beide Vorhöfe sind größer bei CF Patienten, besonders bei nicht überlebende als bei Kontrollen. LA conduit and reservoir Funktionen sind niedriger bei CF Patienten. RA Funktion ist ähnlich zwischen den Gruppen. LAVi und RAVi sind Prädiktoren der Mortalität. Unsere Arbeit betont die Signifikanz der atrialen Bewertung bei CF Patienten.

L'ictus i la insuficiència cardíaca son dues patologies amb elevada morbimortalitat. L'ictus criptogènic (ICr) es defineix como un ictus d'etiologia desconeguda després d'excloure causes potencials i pot arribar fins al 30% dels ictus isquèmics. Estudis previs han demostrat que la fibril·lació auricular (FA) silent segueix sent una possible causa de cardioembolisme i no és infrequent la seva detecció durante el seguiment dels pacients amb ICr. Actualment, la insuficiència cardíaca (IC) és una patologia prevalent, on la disfunció de l'auricula esquerra (AE) pot ser causa o conseqüència. En ambdues malalties, l'estudi funcional de l'AE mitjançant tècniques d'imatge, pot proporcionar paràmetres útils en la pràctica clínica. Per aquesta raò, l'objetiu d'aquesta tesi consistí en avaluar la funció auricular per ecocardiografía amb speckle tracking per al diagnòstic de FA en ICr i com a marcador pronòstic en IC aguda. Es van realitzar dos estudis prospectius que van incloure consecutivament a pacients ingressats per ICr en el primer estudi i per IC aguda en el segon estudi. A tots se'ls practicà un ecocardiograma que va incloure l'estudi de la mida auricular, la fracció d'ejecció auricular esquerra (FEAE) i el strain auricular per speckle tracking. Als pacients ingressats per ICr se'ls va implantar un Holter insertable previ a l'alta de l'hospital i la FA es definí com un episodi de durada ≥ 1 minut en els primers 12 mesos. Als pacientes ingressats per IC aguda es va fer un seguiment clínic a l'alta per a detectar events adversos amb la variable composta de primer reingrès per IC i/o mort cardíaca. En el primer estudi es van incloure 75 pacients consecutius amb ICr amb edat mitja de 76 ± 9 anys (56% varons) i una elevada prevalença d'hipertensió arterial (75%). Es diagnosticà FA en 37 (49%) dels casos. El volum auricular indexat (OR: 1,13; IC al 95%: 1,05-1,21; p = 0,001), la FEAE (OR: 0,80; IC al 95%: 0,72-0,89; p 34mL/m2, atrial dysfunction was associated with AF. In 20 of 53 (38%) patients with non-dilatated atrium, AF was detected and 18 of them also showed atrial dysfunction. Moreover, cut-off values were obtained to distinguish between population with and without AF: LAEF 55%, PALS 21.4% and PACS 12.9%. In the second study related to acute HF, 122 consecutive patients were included, aged 72 ± 11 years (68% men). The three HF phenotypes according to the left ventricular ejection fraction were represented and also sinus rhythm and AF were included. The group with worse atrial function had more decompensated HF than first acute HF and higher E/e' ratio. The AF group had worse atrial function than sinus rhythm. Adverse clinical events happened in 79 (64.8%) cases with a median follow-up of 3.73 years: first rehospitalizations for HF in 65 and cardiac deaths in 14 patients. The group with worse atrial function analysed by strain (reservoir phase or PALS) or LAEF was associated with more rehospitalization for HF and/or cardiac death (PALS HR 2.33; IC 95%: 1.20- 4.52; p = 0.012; LAEF HR 2.24; IC 95%: 1.14-4.38; p = 0.018). In conclusion, the atrial function study by echocardiography with speckle tracking is useful in clinical practice. Its application in CrS allows improving atrial myopathy diagnosis associated with silent AF and its quantification in acute HF is related to adverse clinical outcomes with increased risk of HF readmission and/or cardiac death.

Objectives The aim of this study was to characterize left atrial (LA) pathology in explanted hearts with transthyretin amyloid cardiomyopathy (ATTR-CM); LA mechanics using echocardiographic speckle-tracking in a large cohort of patients with ATTR-CM; and to study the association with mortality. Background The clinical significance of LA involvement in ATTR-CM is of great clinical interest. Methods Congo red staining and immunohistochemistry was performed to assess the presence, type, and extent of amyloid and associated changes in 5 explanted ATTR-CM atria. Echo speckle tracking was used to assess LA reservoir, conduit, contractile function, and stiffness in 906 patients with ATTR-CM (551 wild-type (wt)-ATTR-CM; 93 T60A-ATTR-CM; 241 V122I-ATTR-CM; 21 other). Results There was extensive ATTR amyloid infiltration in the 5 atria, with loss of normal architecture, vessels remodeling, capillary disruption, and subendocardial fibrosis. Echo speckle tracking in 906 patients with ATTR-CM demonstrated increased atrial stiffness (median [25th-75th quartile] 1.83 [1.15-2.92]) that remained independently associated with prognosis after adjusting for known predictors (lnLA stiff: HR: 1.23; 95% CI: 1.03-1.49; P = 0.029). There was substantial impairment of the 3 phasic functional atrial components (reservoir 8.86% [5.94%-12.97%]; conduit 6.5% [4.53%-9.28%]; contraction function 4.0% [2.29%-6.56%]). Atrial contraction was absent in 22.1% of patients whose electrocardiograms showed sinus rhythm (SR) “atrial electromechanical dissociation” (AEMD). AEMD was associated with poorer prognosis compared with patients with SR and effective mechanical contraction (P = 0.0018). AEMD conferred a similar prognosis to patients in atrial fibrillation. Conclusions The phenotype of ATTR-CM includes significant infiltration of the atrial walls, with progressive loss of atrial function and increased stiffness, which is a strong independent predictor of mortality. AEMD emerged as a distinctive phenotype identifying patients in SR with poor prognosis., Central Illustration

Human atrial and ventricular contractions have distinct mechanical characteristics including speed of contraction, volume of blood delivered and the range of pressure generated. Notably, the ventricle expresses predominantly β-cardiac myosin while the atrium expresses mostly the α-isoform. In recent years exploration of the properties of pure α- & β-myosin isoforms have been possible in solution, in isolated myocytes and myofibrils. This allows us to consider the extent to which the atrial vs ventricular mechanical characteristics are defined by the myosin isoform expressed, and how the isoform properties are matched to their physiological roles. To do this we Outline the essential feature of atrial and ventricular contraction; Explore the molecular structural and functional characteristics of the two myosin isoforms; Describe the contractile behaviour of myocytes and myofibrils expressing a single myosin isoform; Finally we outline the outstanding problems in defining the differences between the atria and ventricles. This allowed us consider what features of contraction can and cannot be ascribed to the myosin isoforms present in the atria and ventricles.

Introducao Os cistos sanguineos no coracao sao frequentemente reconhecidos como benignos. Geralmente nao causam sintomas clinicos e sao frequentemente encontrados em bebes menores de dois meses. Na maioria dos casos, os cistos sanguineos estao nas valvulas cardiacas ou suas estruturas de suporte. Os cistos cardiacos em adultos sao extremamente raros, especialmente nas câmaras do coracao. Aqui, relatamos um caso de doenca cardiaca valvular complicada com um cisto sanguineo no atrio direito. As ecocardiografias transtoracica, de contraste e esofagica foram utilizadas [...]

In the past, we generated transgenic mice that overexpress the human histamine 2 (H

Background Significant left-ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy (HCM) may result in symptoms and is associated with adverse outcomes. Although disopyramide can reduce resting gradients, nearly 30% of HCM patients do not respond. We sought to study the clinical and echocardiographic variables associated with disopyramide-induced LVOT-gradient reduction. Methods Forty-one disopyramide-treated HCM patients (average daily-dose 305 mg) were subdivided into two groups: (1) nineteen responders, with a reduction of LVOT-gradients of at least 30% from baseline, and (2) twenty-two non-responders, in whom LVOT-gradients did not change or increased following treatment. All patients had a thorough clinical and echocardiographic assessment pre- and post-treatment initiation. Results Patients who responded to disopyramide had better pretreatment left ventricular (LV) systolic function (LV ejection fraction of 67.9 ± 5.6% vs. 59.7 ± 5.8%, p = 0.0001), better LV global longitudinal strain (−17.9 ± 2.3% vs. −16.1 ± 2.5%, p = 0.048), less mitral regurgitation, smaller LV size (indexed LV end-systolic volume of 16.2 ± 5.1 ml/m2 vs. 23.2 ± 6.8 ml/m2, p = 0.001), and lower LV maximal wall thickness (17.2±3 mm vs.19.2 ± 3.4 mm, p = 0.046). Baseline left atrial (LA) volumes were significantly lower in the responders, with higher indices of LA ejection fraction (62 ± 11.2% vs. 50.5 ± 12.2%, p = 0.005), systolic LA strain (34 ± 12.4% vs. 25.8 ± 10.6%, p = 0.04), and LA strain-rate (1.34 ± 0.49%/sec vs. 0.99 ± 0.24%/sec, p = 0.012). In multivariable analysis, the presence of reduced LV systolic function and systolic LA strain-rate remained independently associated with poor response to disopyramide. Conclusions Obstructive HCM patients with more severe disease at baseline tend to respond less to disopyramide treatment. In those patients, early referral for alcohol septal ablation or myectomy surgery should be considered.

Chloroform has been used over decades in anesthesia before it was replaced by other volatile anesthetics like halothane or sevoflurane. Some of the reasons were inadmissible side effects of chloroform like bradycardia or neural illness. In the present study, we identified members of the G protein-activated inwardly rectifying potassium channel family (Kir3) expressed in Xenopus oocytes as potential common molecular targets for both the neural and cardiac effects of chloroform. Millimolar concentration currents representing a 1:10000 dilution of commercially available chloroform were used in laboratories that augment neuronal Kir3.1/3.2 currents as well as cardiac Kir3.1/3.4. This effect was selective and only observed in currents from Kir3 subunits but not in currents from Kir2 subunits. Augmentation of atrial Kir3.1/3.4 currents leads to an effective drop of the heart rate and a reduction in contraction force in isolated mouse atria.

Aims Galectin‐3 (Gal‐3) is implicated in the pathogenesis of heart failure and is also influenced by ageing. This study aims to determine the extent to which Gal‐3 levels estimate odds of myocardial dysfunction in ageing cohorts, ‘upstream’ prior to clinical disease. Methods and results Four hundred seventy‐five asymptomatic subjects underwent simultaneous assessments of cardiovascular structure and function, with measurements of circulating Gal‐3. Myocardial dysfunction was defined as impaired myocardial relaxation (ratio of peak velocity flow in early diastole E (m/s) to peak velocity flow in late diastole by atrial contraction A (m/s)

Heart failure affects >26 million patients worldwide. Current cardiac devices save lives, but patients suffer complications. Hence, improved devices are needed. Realheart TAH is a novel total artificial heart which has shown promising results in acute pig studies. However, the device design needed to be evaluated in humans. Virtual implantations demonstrated the device fits in two of three patients, but that there was some interference with the left lung. Herein, we used an innovative 3D-printed model with swivelling device components to test the device in human cadavers. Our new method demonstrated how to optimize design to improve the surgical fit.

With the aid of cardiac imaging techniques, recent numerical simulations of left ventricular flow can be patient-specific to better mimic physiological conditions. However, studies with a dynamic mitral valve (MV) remain extremely limited. Even so, the left atrium (LA) is usually simplified to be tubular regardless of its complex structure. Studies on the effect of this simplification are limited and observations are controversial. In this study, both tubular and generic atriums were incorporated in patient-specific simulations with and without the MV to qualitatively and quantitatively estimate the effects of the atrial model on downstream ventricular flow. The patient-specific model was generated based on cardiac magnetic resonance (CMR) images of a healthy volunteer, and the dynamic motion of the MV was defined by the contours acquired along long-axis images. Based on the simulations, the influence of the atrial vortices on ventricular flow was significant in the valveless models in terms of flow structure, kinetic energy (KE) and circulation. Although these effects were suppressed in the presence of the MV, the atrial vortices that survived the passage were not trivial, which was evidenced by reduced strength of circulation and undesired flow pattern in the apical region. The flow structure in the generic atrium also dominated the development of ventricular flow in the valveless model. After the MV was incorporated, its effects on the downstream ventricular flow were considerably reduced but not eliminated. Therefore, a proper modelling of atrial flow is necessary, especially for subjects with high ejection fraction (EF).

Demirel-Yilmaz, Emine/0000-0002-2476-6225; Derici, Mehmet Kursat/0000-0002-8260-7492; Guray, Tulin/0000-0003-4572-1429 WOS: 000455010800015 PubMed: 30529467 Phosphodiesterase enzymes (PDEs) are responsible for the adjustment of cyclic nucleotide levels. Alterations in PDE expressions in different tissues cause conflicts between functional and clinical effects of PDE inhibitors. Therefore, the aim of this study was to investigate the gene and protein expressions and the functional role of PDEs in atrium and ventricle of rat heart The expressions of PDEs were examined in cardiac intact tissues and enzymatically isolated cells. The effects of PDE1-5 inhibitors (vinpocetine, EHNA, milrinone, rolipram, sildenafil, and IBMX) on basal and isoprenaline-stimulated contractions and sinus rate were recorded in the isolated spontaneously beating right atrium and electrically stimulated left papillary muscles. The mRNA and protein levels of PDEs were significantly different in atrial and ventricular intact tissues and isolated myocytes. Atrial contractions were increased with vinpocetine while suppressed by EHNA, milrinone, rolipram, sildenafil and IBMX. Milrinone, sildenafil and IBMX increased the heart rate whereas vinpocetine caused negative chronotropy. Papillary muscle contractions have been increased only with the vinpocetine and IBMX. Both the expression and the action of PDE-1-5 show atrial and ventricular differences. Therefore, these differences should be taken into account in the experimental or therapeutic approaches of the heart. Ankara University Research Foundation Ankara, TurkeyAnkara University [13B3330007] This study was supported by a research grants, 13B3330007 from the Ankara University Research Foundation Ankara, Turkey.

Studies performed in controlled laboratory conditions have shown that environmental thermal application may induce various circulatory changes. We aimed to demonstrate the effect of local climate on hemodynamics according to echocardiography. Echocardiographic studies conducted in ambulatory patients, 18 yr of age or older, between January 2012 and July 2016, at our medical center, for whom climate data on the day of the echocardiogram study were available, were retrospectively included in case climate data. Discomfort index, apparent temperature, temperature-humidity index, and thermal index were computed. Echocardiograms conducted in hotter months (June–November) were compared with those done in colder months (December–May). The cohort consisted of 11,348 individuals, 46.2% women, and mean age of 57.9 ± 18.1 yr. Climate indexes correlated directly with stroke volume ( r = 0.039) and e′ (lateral r = 0.047; septal r = 0.038), and inversely with systolic pulmonary artery pressure (SPAP; r = −0.038) (all P values < 0.05). After adjustment for age and sex, echocardiograms conducted during June–November had a lower chance to show e′ septal < 7 cm/s (odds ratio 0.88, 95% confidence interval 0.78–0.98, P = 0.017) and SPAP > 40 mmHg (odds ratio 0.81, 95% confidence interval 0.67–0.99, P = 0.04) compared with those conducted in other months. The authors concluded that climate may affect hemodynamics, according to echocardiographic assessment in ambulatory patients. NEW & NOTEWORTHY In the present study, we examined 11,348 individuals who underwent ambulatory echocardiography. Analyses of the echocardiographic studies demonstrated that environmental thermal stress, i.e., climate, may affect hemodynamics. Most notably were the effects on diastolic function. Higher values of mitral e′, stroke volume, as well as ejection fraction, and lower values of systolic pulmonary artery pressure and tricuspid regurgitation were demonstrated on hotter days and seasons.

BACKGROUND Septal myectomy relieves left ventricular outflow obstruction (LVOTO) and is associated with excellent long-term outcomes. LVOTO is associated with diastolic dysfunction and increased left atrial (LA) size. We sought to investigate the changes in LA volumes and function postmyectomy and the association between these changes with clinical outcomes postmyectomy. METHODS Sixty-six hypertrophic cardiomyopathy patients undergoing myectomy were retrospectively studied. Preprocedural and 6- to 18-month postmyectomy follow-up transthoracic echocardiographic images were obtained. LA volumes and strain were assessed by two-dimensional speckle-tracking echocardiography. RESULTS Left atrial volumes, that is, indexed maximal, minimal, and pre-A volumes reduced postmyectomy, yet remained increased compared to controls (105.6 ± 34.5 mL vs 84.9 ± 26.7 mL, 45.2 ± 25.7 mL vs 35.4 ± 22.6 mL, 70.1 ± 31.4 mL vs 35.4 ± 22.6 mL, respectively, P

Background The Bachmann bundle (BB) is one of the major interatrial muscular connections. Macroscopic anatomy and electrophysiological properties of BB have so far not been linked, and differences in activation patterns are most likely due to anatomical variations. Objectives The goals of this study were to analyze different activation patterns and couple those wavefronts to epicardial morphological structures on cadaveric hearts. Methods High-resolution epicardial mapping over BB during sinus rhythm was performed in 185 patients undergoing coronary artery bypass graft surgery. The epicardial atrial musculature was macroscopically examined in 19 postmortem dissected human hearts, which are different from those examined in the mapping study. The morphology of BB and surrounding interatrial connections were evaluated. Activation patterns were subsequently linked to morphological variance found in the dissected hearts. Results Epicardial mapping showed that BB is activated in a right-to-left direction in the majority of patients. In almost one-third of patients, a wavefront emerging or entering in the middle of BB was also observed. In some patients, left-to-right activation of BB was observed. BB was macroscopically present in all postmortem hearts. In addition, a newly found posterosuperior bundle was consistently seen, joining BB from the posterior border over the interatrial groove. Other connections identified were the septopulmonary bundle and posterior interatrial connections. Conclusion The morphological interatrial connections correspond to the interatrial pathways observed with high-resolution epicardial mapping of BB. Of these connections, BB and the posterosuperior bundle seem to be most consistent, both morphologically and electrophysiologically.