Prominent Right Ventricle on MPI: RV Hypertrophy

D. Right ventricular hypertrophy (RVH) or elevated RV pressure (pulmonary hypertension, severe tricuspid regurgitation)

The right ventricle is normally thin-walled (much thinner than the LV), so it takes up proportionally less tracer and is usually faintly seen or invisible on standard dose MPI. When the RV myocardium is significantly hypertrophied (from chronically elevated RV pressure — as in pulmonary arterial hypertension, cor pulmonale, or significant RV outflow obstruction), its mass is increased and it becomes prominently visible on MPI, similar in intensity to the LV. Prominent RV visualization is therefore a marker for RV pressure overload. This finding can also be seen in RV infarction (from RCA occlusion proximal to the RV branches), where it may appear as an RV perfusion defect.