case_images: PMC9523255_01
case_images: Right atrium enlargement and severe tricuspid regurgitation in a transthoracic echocardiography. Transthoracic echocardiography shows enlargement of the right atrium and a gap between the septal leaflet and anterior leaflet (A), and severe tricuspid regurgitation was pointed out from the gap (B).
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case_images: F1
case_images: Echocardiography showed severe tricuspid regurgitation (TR) with dilation of the right atrium (RA) (Figures 1A,B), mild mitral regurgitation, and preserved left ventricle (LV) EF in 58%.
case_images: Right atrium enlargement and severe tricuspid regurgitation in a trans-esophageal echocardiography. Trans-esophageal echocardiography shows spherical enlargement of the right atrium (A), severe tricuspid regurgitation swirling in the right atrium was observed (B). While the anterior, septal, and posterior leaflets were indicated when the tricuspid valve was open (C), a regurgitation port was found between the anterior, septal and posterior leaflets, which was also a severe finding (D).
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case_images: F2
case_images: Transesophageal echocardiography showed a spherical RA enlargement, and a regurgitation port was found between the anterior, septal and posterior leaflets, which was also a severe finding (Figures 2A-D).
case_images: Doppler-derived intrarenal venous flows before and after sodium-glucose cotransporter 2 inhibitor administration. After adding sodium-glucose cotransporter 2 inhibitor during 1 months, in color doppler flow images from the right and left kidney, intrarenal venous flow changed from a monophasic (A,B) to a discontinuous pattern with a systolic interruption (C,D).
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case_images: F3
case_images: Inbody 720, Japan Inc., Tokyo) (Table 2). In color doppler flow images from bilateral kidney, IRVF was changed from a monophasic (Figures 3A,B) to a discontinuous pattern with a systolic interruption that was close to a continuous pattern (Figures 3C,D), while TR velocity was decreased to 2.19 m/s.
case_images: Transcutaneous electrical vagus nerve stimulation. For active stimulation, the ear clip was attached to the tragus, which is innervated by the auricular branch of the vagus nerve.
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case_images: F4
case_images: Because tVNS was expected to safely suppress SNS activity, which was considered to be a common pathophysiology for HF and CKD, with dilatation of microvasculature, stimulation of the left ear tragus (Parasym device , Parasym Health, London, UK) (Figure 4) was accomplished after obtaining consent in order to stabilizing autonomic balance.
case_images: Doppler-derived intrarenal venous flows before and after transcutaneous electrical vagus nerve stimulation. After transcutaneous electrical vagus nerve stimulation during 1 h, while the right intrarenal venous flow was not changed as a monophasic pattern (A,C), the left intrarenal venous flow was changed from a discontinuous biphasic pattern as one fusion wave of two waves (B) to a discontinuous pattern with a systolic interruption (D).
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case_images: F5
case_images: IRVF was not changed as a monophasic pattern (Figures 5A,C), the left IRVF has been dramatically changed from a discontinuous biphasic pattern as one fusion wave of two waves (Figure 5B) to a discontinuous pattern with a systolic interruption (Figure 5D). In addition, TR velocity was changed from 2.88 to 2.61 m/s, while tricuspid annular plane systolic excursion (TAPSE) was changed from 18 to 27 mm after tVNS.
case_images: Doppler-derived intrarenal venous flows before and after transcutaneous electrical vagus nerve stimulation. Right ventricular free-wall longitudinal strain and four chamber longitudinal strain were changed before (A) and after transcutaneous electrical vagus nerve stimulation during 1 h (B).
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case_images: F6
case_images: Moreover, right ventricular (RV) free-wall longitudinal strain (RVFWSL) and RV four chamber longitudinal strain (RV4CSL) were improved from -7.9 and -8.3% to -19.5 and -19.1% after tVNS (Figure 6).