Download Left Atrial Dissection After Left Ventricular Aneurysm Repair

[-99] Left Atrial Dissection After Left Ventricular Aneurysm Repair
1 Youngblood
S, 2 Pisklak P, 3 Tolpin D, 3 Pan W
Heart Institute, Baylor College of Medicine , Houston , TX, USA; 2 Baylor College of Medicine ,
Houston , TX, USA; 3 Texas Heart Institute, St. Luke’s Episcopal Hospital , Houston , TX, USA
1 Texas
Introduction: Left atrial dissection is a rare complication of cardiac surgery. Limitation of mitral inflow
can result in hemodynamic collapse, and traditional monitoring may fail to suggest the diagnosis. We
present the case of a gentleman who developed a left atrial (LA) dissection after repair of a post-infarction
ventricular aneurysm. Transesophageal echocardiography (TEE) was used to establish the diagnosis of an
atrial dissection that almost completely occluded the mitral valve, limiting ventricular filling and causing
hemodynamic instability.
Case Scenario: A 52-year-old man underwent aortocoronary bypass and repair of a large inferior
ventricular wall aneurysm. Preoperative TEE revealed an ejection fraction of 20%. Near the mitral
annulus, a polyester patch was implanted to exclude the aneurysm sac, and the patient was weaned with
difficulty from cardiopulmonary bypass (CPB) via pharmacologic and intra-aortic balloon support.
On post-CPB TEE, a hypo-echoic structure was visualized along the interatrial septum and posterior left
atrial wall that obstructed the mitral orifice. Color-flow Doppler revealed systolic blood flow within this
structure that originated from the excluded aneurysm sac. CPB was reinstituted, and the left atrium was
explored. A corresponding cavity was noted within the interatrial septum that communicated with the site
of the excluded aneurysm. After drainage and closure of the space, the patient was again weaned from
CPB, and TEE examination revealed complete LA dissection exclusion.
Discussion: LA dissection is a rare finding reported after aortocoronary bypass (1), mitral/aortic valve
repair (2,3), and pulmonary vein cannulation (4). Diagnosis requires TEE monitoring, as central venous
and pulmonary artery pressures would mirror the profile of ventricular failure. Classically, TEE reveals a
hypo-echoic space within the interatrial septum or wall. Identification of the dissection source is essential
to guide surgical repair. Color Doppler serves as a screening tool to localize the source of flow into the
dissection, and spectral Doppler can characterize the velocity of blood flow into the dissection to allow the
source to be defined as high- or low-pressure.
In this case, the LV aneurysm was incompletely excluded and the inferior wall shared by the aneurysm
and LA was disrupted resulting in diversion of blood flow into the LA wall. The dissection impeded mitral
inflow, compromising hemodynamics and causing difficult weaning from CPB. Color-flow Doppler
revealed systolic flow into the dissection from the incompletely excluded LV aneurysm along the shared
posterior wall. TEE proved vital for both diagnosing and guiding management of this rare complication.
1) Anesth Analg 2003;97:1605-7
2) Echocardiography 2000;17:259-61
3) J Cardiothorac Vasc Anesth 2011;25:309-10
4) Anesth Analg 2009;109:1409-12
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