Discusssion

Cardiac pseudoaneurysm is defined as a rupture of the myocardium that is contained by pericardial adhesions or the epicardial wall. Myocardial rupture directly causing death reportedly occurs in 7% to 10% of patients after acute myocardial infarction; pseudoaneurysm, a contained rupture, is reportedly a rare complication of myocardial infarction. Pseudoaneurysm can also occur after cardiac surgery, chest trauma, and endocarditis. The wall of a pseudoaneurysm consists of fibrous tissue and lacks the structural elements found in a normal cardiac wall.
Various imaging methods have been used to diagnose pseudoaneurysm, including two-dimensional echocardiography, computed tomography, magnetic resonance imaging, and left ventricular angiography. Chest radiography sometimes shows a localized bulge on the cardiac silhouette.
Contrast angiography was the first imaging method used to detect pseudoaneurysms. The presence of a periventricular sac that communicated with the left ventricle through a narrow orifice was considered most suggestive of a pseudoaneurysm. This finding differs from findings in a true aneurysm, which typically has a large communicating neck. In addition, pseudoaneurysms appear avascular on coronary angiography.
The echocardiographic detection of pseudoaneurysm was first reported in 1975. The echocardiographic features typical of pseudoaneurysms include sharp discontinuity of the endocardial image at the site of communication of the pseudoaneurysm with the left ventricular cavity and an orifice that is relatively narrow in comparison with the diameter of the pseudoaneurysm. Pulsed-wave and color flow Doppler echocardiography have been useful in visualizing the high-velocity, turbulent, bi-directional flow between the left ventricle and a pseudoaneurysm.
On computed tomography, pseudoaneurysms are characterized by an abrupt disappearance of the myocardial wall at the border of the pseudoaneurysm. Magnetic resonance imaging shows the low signal of the pericardium, which constitutes the only wall of the pseudoaneurysm.
An important clinical feature of pseudoaneurysms is their reported propensity for further rupture and fatal outcome. Because of these observations, early surgery is recommended even for asymptomatic patients.