Left Atrial Wall Dissection after Mitral Valve Replacement
A 68-year-old Korean female presented with moderate mitral stenosis, mild mitral regurgitation, moderate tricuspid regurgitation and mild aortic regurgitation. She had no past medical history other than valve diseases and was scheduled for mitral valve replacement and tricuspid annuloplasty. Standard monitors were placed, and right radial arterial cannulation was done for continuous blood pressure monitoring. After preoxygenation, general anesthesia was induced with propofol and remifentanil, infused with a target-site concentration-control infusion device (Base Prima Orchestra, Fresenius Vial, Brezins, France). Tracheal intubation was done with a 7.0 mm tube and a triple lumen central catheter (via left subclavian vein) and Swan-Ganz catheter (PAC: Swan-Ganz CCOmbo V Model 774HF75w: Edwards Lifesciences LLC, Irvine, CA, USA) (via right internal jugular vein) were placed. Continuous cardiac output monitoring and mixed venous oxygen saturation monitoring was done by CCO/Oxymetry/volumetric monitor (Vigilance Monitor: Edwards Lifesciences LLC, Irvine, CA, USA). Transesophageal echocardiography (TEE) findings were consistent with previous transthoracic echocardiography (TTE). During surgery, radiofrequency ablation was done around the coronary sinus and pulmonary vein box lesion, and right side Maze procedure was done. The mitral valve was replaced with a St. Jude Medical (St. Jude Medical Inc., St. Paul, MN, USA) supra-epic 29 mm tissue valve. The LA auricle was externally obliterated with a 5-0 prolene continuous suture and a tricuspid annuloplasty was done with a Duran ring (Medtronic, Minneapolis, MN, USA) 27 mm. After closing the atrium, the patient was weaned off cardiopulmonary bypass with inotropic support of 5 µg/kg/min of dobutamine. The TEE exam during weaning showed a well-seated prosthetic valve and no paravalvular leakage; however, the patient developed posterolateral atrial wall dissection. A false chamber formed in the LA wall and was 2 × 2.5 cm in size (). A surgeon explored the heart externally but could not find any engorgement. The TEE showed small blood flow pouring into the false chamber but it decreased and disappeared in 30 minutes. The false chamber did not seem to increase in size and showed spontaneous echogenic contrast, that is, no communication with the true atrial space. Additionally, the pulmonary venous flow was not hindered by that chamber (). We had a discussion with the surgeon and concluded the risk of re-exploring and repairing the dissection exceeded that of the dissection itself. The patient was uneventfully weaned off CPB. Total CPB time was 4 hours 47 minutes; the aortic cross clamp time was 3 hours 45 minutes. Follow-up TTE taken 6 days after surgery showed normal pulmonary vein flow, and the false chamber was not visible (). The patient agreed to have her case presented to the public for academic purposes.