Discussion
Incidence of left atrial dissection is low and is reported to be 0.16%
following mitral valve surgery and 0.02% following coronary artery
bypass grafting . This condition is being increasingly recognized
following surgery because of increased use of TEE since 1990. Left
atrial dissection following PCI is less common and literature search is
limited to sporadic case reports, it is only after 2000 that case
reports of LatD as a complication of percutaneous procedures started
appearing in literature
Left atrial dissection has a variable clinical course. Cases described
have ranged from self-limiting stable disease to lethal outcomes.
Mortality rate of up to 13.8% has been described in surgical
literature. Left atrial dissection presents immediately and majority of
the cases, though it has been reported to occur months or even
years after the procedure. Dyspnea is the commonest presenting symptom
and present in about a quarter of the patients. Chest pain and
arrhythmias have been reported, about 10% of the patients are
asymptomatic.
Our case was readily recognized by transthoracic echocardiography.
Duplication of left atrial free wall is the most common abnormality seen
on echocardiography . Left atrial dissection, especially if there is
thrombus in the false lumen, can mimic left atrial mass. Cardiac
tamponade, hiatal hernia, plueropericardial cysts causing extrinsic
compression of the left atrium can also mimic left atrial
dissection.Multimodality imaging has been recommended to confirm
diagnosis of this rare condition. In our case CT scanning coupled with
TTE corroborated the diagnosis.
Pathogenesis of left atrial dissection is varied. Majority of the cases
arise from injury along the AV junction which results in separation of
the endocardium of the left atrium causing the dissection cavity. Other
entry points are also possible and likely explain LatD arising from
aortic valve replacement, percutaneous coronary interventions and
pulmonary vein cannulation Similar to the cases reported by Solzbach and
Cresce et al, we too believe that a distal perforation from guide wire
manipulation resulted in left atrial injury.
Indication for surgery should be based on clinical presentation. in
patients with hemodynamic instability prompt surgical approach is
warranted. Surgical technique involves obliteration of the false cavity
and addressing the entry point if possible. Medical management or
non-operative approach, supported by serial imaging is reasonable in a
stable patient. Reversal of anticoagulation when feasible should also be
considered.
List of figures:
Figure
1: LA dissection 2C view
(arrow)
Figure 2: LA dissection 4C view (arrow)
Figure 3: LA filled with thrombus
(star)
Figure
4: LA thrombus with active leak (arrow)