COMMENT
Acute post-infarction posterior VSD causes a left to right shunt with
increased pulmonary blood flow resulting in biventricular failure. An
early surgical intervention without optimizing the hemodynamics can lead
to high mortality (4). In addition, surgical repair of the posteriorly
positioned VSD can be more challenging and is often associated with
higher mortality (1, 2). Mechanical circulatory support in the form of a
veno-arterial ECMO can help stabilize the patient and drain the right
ventricle, thus preventing acute pulmonary edema. Moreover left
ventricle can be decompressed into the right ventricle through the VSD
so that left ventricular distention can also be avoided. Hence a VA ECMO
can help the patient to recover from acute cardiogenic shock and give
time for the VSD to fibrose so as to aid in operative repair (5).
Both trans-atrial and trans-ventricular techniques have been described
in the literature to access the post-infarction posterior VSD. We feel
the trans-atrial approach is associated with less bleeding complications
but a higher need of tricuspid valve replacement in comparison to a
trans-ventricular repair (6). In our case, the papillary muscle to the
posterior leaflet of the tricuspid valve had already necrosed and
ruptured, resulting in severe tricuspid regurgitation. Hence,
replacement of tricuspid valve was likely going to be mandatory.
Based on our experience, we recommend that all patients in cardiogenic
shock due to a post-infarct posterior VSD should be considered for VA
ECMO support. Staged right atrial approach gives excellent exposure and
helps avoid morbidity and mortality due to bleeding complications
associated with ventriculotomy. The timing of the surgical intervention
should be tailored depending upon the hemodynamic stability and presence
of the cardiogenic shock.