Atrial septal dissection after mitral valve replacement demonstrated by transesophageal echocardiography

Left atrial dissection: pathogenesis, clinical course, and transesophageal echocardiographic recognition

Left atrial dissection is an uncommon entity. It is generally associated with mitral valve replacement, but other predisposing factors should be considered in pathogenesis. We discuss a series of 11 patients with pathologically confirmed left atrial dissection who had been diagnosed previously by transesophageal echocardiography. Predisposing factors and surgical or pathologic findings were reviewed to identify the pathogenic mechanism and to explain the clinical course, hemodynamic disorder, and echocardiographic features. Dissection of the coronary sinus secondary to retrograde cardioplegia, endocarditis, cardiac rupture after myocardial infarction, and blunt chest trauma also could be related to its development. Transesophageal echocardiography identified a mobile intimal flap of the atrial wall that was creating a false chamber and allowed accurate diagnosis of prosthetic mitral valve function, endocarditis complications, and a left ventricular pseudoaneurysm after acute myocardial infarction. Color flow Doppler was particularly useful in identifying complications: communication between the false chamber and true left atria, permitting mitral regurgitation through the periannular route; development of atrial shunts; and severe tricuspid regurgitation caused by disruption of the anterior papillary muscle.

Dissection of atrial septum after mitral valve replacement

We report a patient who presented with paraprosthetic leak complicated by dissection of the interatrial septum after mitral valve replacement. A review of the literature provides confirmation that only 3 cases have been previously reported of this potential, albeit extremely rare, complication of prosthetic mitral valve replacement. Prosthesis oversizing and improper mitral annular handling appeared to be the predisposing factors of this complication.