What cardiac condition would prevent diastolic right ventricular collapse?

Diastolic right ventricular collapse is a phenomenon typically associated with severe pressure overload on the right ventricle, which can occur in certain clinical scenarios such as cardiac tamponade or pulmonary hypertension. In the case of pulmonary hypertension, the elevated pressure in the pulmonary artery leads to an increased right ventricular systolic pressure; therefore, the right ventricle is less likely to collapse during diastole due to the pressure differential created.

In contrast, conditions such as cardiac tamponade are characterized by the accumulation of fluid in the pericardial space, which exerts pressure on the heart and can lead to diastolic collapse of the right ventricle. Myocardial infarction can lead to changes in myocardial contractility and may not directly cause right ventricular collapse, while aortic stenosis primarily affects the left side of the heart and does not generally influence right ventricular mechanics in the same manner.

Thus, pulmonary hypertension prevents diastolic right ventricular collapse by imposing higher pressures that maintain the structural integrity of the right ventricle during the diastolic filling phase.