Refractory ventricular tachycardia and heart failure due to anti-mitochondrial antibody-positive inflammatory myopathy.

Background: Anti-mitochondrial antibody (AMA)-positive inflammatory myopathy, a rare type of idiopathic inflammatory myopathy which was frequently difficult to diagnose, can affect muscles and the structure and electrical conduction of the heart. Early identification and treatment of this myopathy can prevent serious cardiovascular adverse events and improve cardiac function.

Case Presentation: We report a patient who experienced repeated syncope, ventricular tachycardia (VT) and heart failure accompanied by weakness and muscle atrophy.

Ripple mapping-guided atrial tachycardia ablation following open-heart surgery.

Ripple mapping can make the visualization of activation conduction on a 3-dimensional voltage map and is useful tool for scar-related organized atrial tachycardia (AT). This study sought to assess the efficacy of ripple mapping for interpreting reentrant circuits and critical isthmus in postoperative ATs. 34 consecutive patients with a history of mitral valve surgery (mean age, 54.

Human trophoblast-derived exosomes attenuate doxorubicin-induced cardiac injury by regulating miR-200b and downstream Zeb1.

Human trophoblast stem cells (TSCs) have been confirmed to play a cardioprotective role in heart failure. However, whether trophoblast stem cell-derived exosomes (TSC-Exos) can protect cardiomyocytes from doxorubicin (Dox)-induced injury remains unclear. In the present study, TSC-Exos were isolated from the supernatants of human trophoblasts using the ultracentrifugation method and characterized by transmission electron microscopy and western blotting.

Next-generation sequencing identifies a novel heterozygous I229T mutation on LMNA associated with familial cardiac conduction disease.

LMNA gene encodes Lamin A and C (Lamin A/C), which are intermediate filament protein implicating in DNA replication and transcription. Mutations in LMNA are validated to cause cardiac conduction disease (CCD) and cardiomyopathy.In a Chinese family, we identified 5 members harboring the identical heterozygous LMNA (c.

Inhibition of RAGE by FPS-ZM1 alleviates renal injury in spontaneously hypertensive rats.

The current study was designed to examine the protection of RAGE-specific inhibitor FPS-ZM1 against renal injury in spontaneously hypertensive rats (SHR) and investigate the underlying mechanism. The adult male SHR were treated with FPS-ZM1 via oral gavages for 12 weeks, and age-matched male Wistar-Kyoto rats (WKY) were used as control. Treatment of SHR with FPS-ZM1 slightly reduced blood pressure, and significantly improved baroreflex sensitivity in SHR.

Brugada Syndrome Caused by Sodium Channel Dysfunction Associated with a SCN1B Variant A197V.

Objective: We aimed to identify and characterize a SCN1B variant, A197V, associated with Brugada Syndrome (BrS).

Methods: Whole-exome sequencing was employed to explore the potential causative genes in 8 unrelated clinically diagnosed BrS patients. A197V variant was only detected in exon 4 of SCN1B in a 46 year old patient, who was admitted due to syncope.

PDK1-AKT signaling pathway regulates the expression and function of cardiac hyperpolarization-activated cyclic nucleotide-modulated channels.

Aim: The enzyme 3-phosphoinositide-dependent protein kinase-1 (PDK1) is associated with cardiac and pathological remodeling and ion channel function regulation. However, whether it regulates hyperpolarization-activated cyclic nucleotide-modulated channels (HCNs) remains unclear.

Main Methods: In the atrial myocytes of heart-specific PDK1 "knockout" mouse model and neonatal mice, protein kinase B (AKT)-related inhibitors or agonists as well as knockdown or overexpression plasmids were used to study the relationship between PDK1 and HCNs.

Residual flow may increase the risk of adverse events in patients received combined catheter ablation and transcatheter left atrial appendage closure for nonvalvular atrial fibrillation: a meta-analysis.

Background: Catheter ablation (CA) and left atrial appendage closure (LAAC) have been combined into a novel one-stop procedure for patients with atrial fibrillation (AF). However, postoperative complications are relatively common in patients undergoing LAAC; the complications, including residual flow, increase in the risk of bleeding, or other adverse events, are unknown in patients receiving one-stop therapy. Therefore, we tried to evaluate the adverse events of CA and LAAC hybrid therapy in patients with nonvalvular AF.

AMPK-mediated degradation of Nav1.5 through autophagy.

The voltage-gated cardiac sodium channel, Nav1.5, is the key component that controls cardiac excitative electrical impulse and propagation. However, the dynamic alterations of Nav1.

Sex-specific mortality differences in heart failure patients with ischemia receiving cardiac resynchronization therapy.

Background: Recent studies have reported prognosis differences between male and female heart failure patients following cardiac resynchronization therapy (CRT). However, the potential clinical factors that underpin these differences remain to be elucidated.

Methods: A meta-analysis was performed to investigate the factors that characterize sex-specific differences following CRT.

CLOCK-BMAL1 regulate the cardiac L-type calcium channel subunit CACNA1C through PI3K-Akt signaling pathway.

The heterodimerized transcription factors CLOCK-BMAL1 regulate the cardiomyocyte circadian rhythms. The L-type calcium currents play important role in the cardiac electrogenesis and arrhythmogenesis. Whether and how the CLOCK-BMAL1 regulate the cardiac L-type calcium channels are yet to be determined.

Hemoptysis due to aspirin treatment alternative to warfarin therapy in a patient with atrial fibrillation.

An 80-year-old female with a history of hypertension and atrial fibrillation had been receiving warfarin anticoagulant therapy and had stably maintained an international normalized ratio (INR) within the 2.0-3.0 range.

Prolonged action potential duration in cardiac ablation of PDK1 mice.

The involvement of the AGC protein kinase family in regulating arrhythmia has drawn considerable attention, but the underlying mechanisms are still not clear. The aim of this study is to explore the role of 3-phosphoinositide-dependent protein kinase-1 (PDK1), one of upstream protein kinases of the AGC protein kinase family, in the pathogenesis of dysregulated electrophysiological basis. PDK1(F/F) αMHC-Cre mice and PDK1(F/F) mice were divided into experiment group and control group.

Deletion of PDK1 causes cardiac sodium current reduction in mice.

Background: The AGC protein kinase family regulates multiple cellular functions. 3-phosphoinositide-dependent protein kinase-1 (PDK1) is involved in the pathogenesis of arrhythmia, and its downstream factor, Forkhead box O1 (Foxo1), negatively regulates the expression of the cardiac sodium channel, Nav1.5.

The effects of A-803467 on cardiac Nav1.5 channels.

A-803467 is a selective Nav1.8 blocker, but its mechanism of action at cardiac sodium channels is uncertain. Thus, we investigated the mechanistic effects of A-803467 on cardiac sodium channels in isolated mouse ventricular myocytes and in human embryonic kidney 293 (HEK293) cell lines that transiently expressed Nav1.

Cardiac ablation of Rheb1 reduces sodium currents in infant mice.

Objective: The Ras homolog enriched in brain gene (Rheb) is a center player within the insulin/Rheb/Mammalian Target of Rapamycin (mTOR) pathway, and plays a critical role in regulating cellular growth. Rheb-/- embryos have been reported to die around midgestation, due to the defects of the development of the cardiovascular system. Recent studies from ours and another group consistently showed that Rheb1 was indispensable for the cardiac hypertrophic growth after early postnatal period.

Down-regulation of ATBF1 activates STAT3 signaling via PIAS3 in pacing-induced HL-1 atrial myocytes.

Atrial fibrillation (AF) is progressive and is the most common clinical arrhythmia. It is associated with inflammatory changes characterized by signal transducer and activator of transcription 3 (STAT3) signaling. A zinc finger homeobox 3 (ZFHX3, also named AT-motif binding factor 1, ATBF1) gene variant has been found in patients with AF.

Cardiac ablation of Rheb1 induces impaired heart growth, endoplasmic reticulum-associated apoptosis and heart failure in infant mice.

Ras homologue enriched in brain 1 (Rheb1) plays an important role in a variety of cellular processes. In this study, we investigate the role of Rheb1 in the post-natal heart. We found that deletion of the gene responsible for production of Rheb1 from cardiomyocytes of post-natal mice resulted in malignant arrhythmias, heart failure, and premature death of these mice.