Hyperacute Iatrogenic Atrial Septal Defect Expansion Driven by Tricuspid Regurgitation Jet Impingement

Figures

• 

  Figure 1. Transthoracic Echocardiography Upon Admission Apical 4-chamber view with color Doppler. (A) Severe atrial functional mitral regurgitation with a significant eccentric jet. (B) Moderate-to-severe functional tricuspid regurgitation. The massive biatrial enlargement and advanced remodeling serve as the mechanical substrate for subsequent hemodynamic deterioration.

• 

  Figure 2. Baseline iASD Assessment Immediately Post-M-TEER Intraprocedural transesophageal echocardiography at the conclusion of the procedure. (A) Two-dimensional (2D) color Doppler showing the initial left-to-right shunt after 24-F sheath withdrawal. (B) 3D quantification analysis demonstrating an iatrogenic atrial septal defect (iASD) orifice area of 0.51 cm2 (major/minor axis: 15.5/4.5 mm). LA = left atrium; M-TEER = mitral transcatheter edge-to-edge repair; RA = right atrium.

• 

  Figure 3. Acute Hemodynamic Collapse and Mechanical Ominous Sign Bedside transthoracic echocardiography during cardiogenic shock. (A) Successfully reduced mitral regurgitation (mild) but significantly exacerbated severe tricuspid regurgitation (TR). (B) High-velocity TR jet directly impinging on the interatrial septum. (C and D) Subcostal view revealing a large iatrogenic atrial septal defect with bidirectional shunting: (C) left-to-right and (D) right-to-left flow. (E) Color Doppler M-mode confirming the complex bidirectional shunt.

• 

  Figure 4. Rapid Morphological Evolution Emergency transesophageal echocardiography during the acute phase. (A) Side-by-side 2-dimensional B-mode and color Doppler views capturing the high-velocity tricuspid regurgitation jet surging directly into the iASD, acting as a “hydrodynamic wedge.” (B) Repeat 3-dimensional quantification analysis documenting a dramatic expansion of the iASD; the orifice area more than doubled to 1.22 cm2 (major/minor axis: 18.5/6.0 mm). This rapid evolution underscores the mechanical fragility of the remodeled septum under the mechanical stress of high-kinetic eccentric jet impingement. iASD = iatrogenic atrial septal defect; LA = left atrium; RA = right atrium.

• 

  Figure 5. Final Result of Emergency Iatrogenic ASD Closure Transesophageal echocardiography after device release. Still image demonstrating the 18-mm Occlutech Figulla Flex II ASD occluder in its final position. The thinned, overstretched interatrial septum is securely sandwiched between the disks. This was achieved through a stationary deployment technique (Video 4) to avoid further mechanical tearing. The precise alignment ensures complete shunt elimination while preserving the integrity of the friable tissue. ASD = atrial septal defect.

• 

  Figure 6. Postprocedural Recovery and Device Stability Transthoracic echocardiography on postprocedural day 1. (A) Stable mitral repair (mild mitral regurgitation) and elimination of the iatrogenic shunt. (B) Reduction in TR to a moderate level. (C) The persistent TR jet is seen directly impinging on the occluder, which acts as a mechanical barrier, protecting the friable septum from further tearing. TR = tricuspid regurgitation.

• 

  Visual Summary. The Mechanical Vicious Cycle of iASD Expansion This figure integrates a mechanistic schema (left) with sequential echocardiographic evidence (right) to illustrate the process of septal failure. Top (Initial State): 3D quantification (3DQ) analysis demonstrates a stable initial iASD with an orifice area of 0.51 cm2. Middle (The Trigger): Color Doppler captures the high-velocity TR jet surging directly into the iASD. This illustrates the “hydrodynamic wedge” effect, concentrating mechanical stress on the friable septal margins. Bottom (Catastrophic Expansion): Repeat 3DQ analysis documents a dramatic expansion of the iASD; the orifice area more than doubled to 1.22 cm2. Conclusion: In patients with advanced atrial cardiomyopathy, the concentrated kinetic energy of a tricuspid regurgitation jet can act as a “hydrodynamic wedge,” triggering rapid mechanical failure of the atrial septum and subsequent cardiogenic shock. aFMR = atrial functional mitral regurgitation; GC = guiding catheter; HF = heart failure; iASD = iatrogenic atrial septal defect; LA = left atrium; LAP = left atrial pressure; LV = left ventricular; M-TEER = mitral transcatheter edge-to-edge repair; RA = right atrium;…