SARS-CoV-2 spike receptor-binding domain is internalized and promotes protein ISGylation in human induced pluripotent stem cell-derived cardiomyocytes.

Although an increased risk of myocarditis has been observed after vaccination with mRNA encoding severe acute respiratory syndrome coronavirus 2 spike protein, its underlying mechanism has not been elucidated. This study investigated the direct effects of spike receptor-binding domain (S-RBD) on human cardiomyocytes differentiated from induced pluripotent stem cells (iPSC-CMs). Immunostaining experiments using ACE2 wild-type (WT) and knockout (KO) iPSC-CMs treated with purified S-RBD demonstrated that S-RBD was bound to ACE2 and internalized into the subcellular space in the iPSC-CMs, depending on ACE2.

Usefulness of electron microscopy in the diagnosis of wild-type transthyretin cardiac amyloidosis.

Wild-type transthyretin cardiac amyloidosis (ATTRwt) has been recognized as an important cause of heart failure with preserved ejection fraction; thus, its accurate diagnosis is crucial. Herein, we describe the case of a 76-year-old man who presented with dyspnea and palpitation. On observing the laboratory evaluations and clinical course, we suspected cardiac amyloidosis.

A cavotricuspid isthmus pouch revealed to be a breakout site for gap conduction of recurrent common atrial flutter.

A cavotricuspid isthmus pouch can be a breakout site for gap conduction of cavotricuspid isthmus block line. If the previous block line is electrically silent, high-density 3-D mapping and pouchgraphy are useful to find the pouch and ablate within it.

Pseudoblock of cavotricuspid isthmus via detouring gap conduction.

To detect detouring gap conduction, as demonstrated in this case, 3-D mapping is useful in addition to conventional methods.

Disappearance of an anticoagulation-resistant left atrial appendage thrombus after administration of low-dose pimobendan.

Anticoagulation therapy is essential for preventing thrombus formation in the left atrial appendage (LAA) and subsequent ischemic strokes in patients with atrial fibrillation (AF). The complete disappearance of any existing LAA thrombi is crucial before AF ablation. Currently, warfarin and direct oral anticoagulants are widely used for this purpose.

Incidence of deep vein thrombosis from screening by venous ultrasonography in Japanese patients.

The aim of the present study was to investigate the incidence of deep vein thrombosis (DVT) patients in a Japanese population by screening them with venous ultrasonography. This retrospective, single-center analysis examined 963 patients who underwent venous ultrasonography in 2015. The primary outcome was the incidence of DVT, and secondary outcomes were predictive factors of DVT in patient characteristics, treatment strategy for DVT patients, and proportion of post thrombotic syndrome (PTS).