Final answer:
The typical echocardiographic finding in acute pulmonary embolism is right ventricular dilatation, caused by increased resistance in the pulmonary circuit that the right ventricle must overcome.
Step-by-step explanation:
The two-dimensional echocardiographic finding in acute pulmonary embolism is commonly C. Right ventricular dilatation. This occurs because when a pulmonary embolism impedes blood flow through the pulmonary circuit, it causes increased resistance against the right ventricle. The right ventricle has to work harder to pump blood through the narrowed pulmonary arteries, which can lead to dilatation. The left ventricle's workload does not initially change, so you would not see left ventricular dilatation or left ventricular hypertrophy as a direct result of an acute pulmonary embolism. However, chronic pressure overload can lead to right ventricular hypertrophy over time, which is not the usual immediate echocardiographic finding in acute cases.