Transcatheter Aortic Valve Replacement Reverses Heyde Syndrome: A Case Report of Severe Aortic Stenosis and Gastrointestinal Bleeding

Figures

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  Figure 1. (A) Transthoracic echocardiography (TTE) images of the patient: the maximum peak gradient (AV maxPG) across the AV was 76.71 mmHg, the maximum systolic flow velocity (AV Vmax) was 4.38 m/s, and the mean gradient (AV mean PG) was 46.72 mmHg. (B) Transesophageal echocardiography showing a severely calcified aortic valve, suggestive of severe aortic stenosis.

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  Figure 2. Aortic valve area (AVA) of 0.60 cm2, measured by planimetry in TOE (green outline).

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  Figure 3. Video capsule endoscopy demonstrating vascular lesions in the small bowel. (A) Angiodysplasia is visualized as a discrete, reddish, ectatic lesion on the mucosal surface. (B) Telangiectasias appear as multiple, punctate, red spots scattered throughout the small bowel mucosa, indicative of dilated capillaries.

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  Figure 4. Calcified aortic leaflets (A) and mildly dilated ascending thoracic aorta with calcified plaques (B). (A) Detailed view of calcified aortic valve leaflets, highlighted by color markers (green, yellow, and red) that correspond to different regions of interest. Calcification is visible as dense areas in the images, indicating mineral deposits that reduce leaflet flexibility and affect valve function. (B) A three-dimensional reconstruction of the ascending thoracic aorta reveals mild dilation and the presence of calcified plaques along the vessel wall. The calcifications are depicted as dense, irregular structures within the aortic wall. (C) Computed tomography angiography demonstrating the angle between the aortic annulus plane and the axial plane (annular angulation) at 41°, suitable for TAVR.

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  Figure 5. Pre-procedural imaging demonstrating favorable iliofemoral anatomy for transcatheter aortic valve replacement (TAVR). (A) Three-dimensional reconstruction of the right iliofemoral artery shows adequate vessel diameter and minimal tortuosity, supporting safe vascular access for TAVR. Cross-sectional measurements at multiple levels indicate average diameters ranging from 5.2 mm to 8.1 mm, ensuring compatibility with delivery systems. (B) Corresponding reconstruction of the left iliofemoral artery reveals similarly favorable dimensions, with average diameters ranging from 5.9 mm to 8.3 mm and smooth vessel pathways.

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  Figure 6. Coronary angiography demonstrating no significant atherosclerotic lesions. (A) Right coronary artery visualized in the left anterior oblique (LAO) cranial projection, showing smooth vessel contours and uninterrupted blood flow. (B) Left coronary artery depicted in the right anterior oblique (RAO) caudal projection, illustrating clear lumen without evidence of stenosis or irregularities. (C) Left coronary artery visualized in the left anterior oblique (LAO) cranial projection, confirming favorable anatomy and absence of obstructive lesions. These findings suggest optimal coronary perfusion conditions and low risk of ischemic complications.

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  Figure 7. Successful deployment of the aortic valve prosthesis with optimal positioning confirmed. A pigtail catheter is positioned at the aortic valve (AV) to monitor hemodynamic parameters during deployment. An electrostimulation lead is visible in the right ventricle (RV), ensuring temporary pacing support throughout the procedure to allow valve deployment, as well as a prophylactic measure in case of iatrogenic 3rd-degree heart block.

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  Figure 8. The pathophysiology of Heyde’s syndrome. Severe aortic stenosis produces high shear stress (>5000 dyne/cm2: the threshold for von Willebrand factor to change its conformation from globular to elongated shape). The elongated shape of the vWF exposes the A2 domain, allowing ADAMTS13 to bind and cleave vWF multimers into monomers, thereby reducing its clotting activity and VEGF-A inhibition. Clotting activity reduction predisposes the patient to bleeding, especially from the gastrointestinal mucosa. Increased concentrations of VEGF-A promote angiogenesis, leading to gastrointestinal angiodysplasia.