Review of Movahed's sign (D shaped left ventricle seen on gated SPECT) suggestive of right ventricular overload.

Recently, D shaped ventricle seen on gated SPECT imaging (Movahed's sign) has shown to correlate with right ventricular overload similar to the D shape ventricle seen on echocardiography. Right ventricle (RV) imaging during gated SPECT studies is challenging because of the low tracer uptake due to relatively smaller right ventricular myocardial mass and lower coronary flow to the RV. Increased mass or workload causes higher tracer uptake in the RV wall secondary to increase in RV wall thickness and higher coronary flow. Furthermore, increased RV volume or pressure load can cause displacement of the septum towards the left ventricle causing septal flattening and a D shaped configuration of the left ventricular septum. This is an important finding that should be a part of nuclear gated SPECT interpretation.