Differential Diagnosis for Right to Left Shunting and Elevated Right Ventricular Pressure
- Single Most Likely Diagnosis
- Patent Foramen Ovale (PFO) or Atrial Septal Defect (ASD) with pulmonary hypertension: This is likely because the presence of right to left shunting on a bubble test is indicative of an intracardiac shunt, and elevated right ventricular pressure from tricuspid regurgitation can be a sign of pulmonary hypertension, which can lead to right to left shunting in the presence of a PFO or ASD.
- Other Likely Diagnoses
- Ventricular Septal Defect (VSD) with pulmonary hypertension: Similar to PFO or ASD, a VSD can cause right to left shunting, especially if pulmonary hypertension develops, increasing the pressure in the right ventricle and causing shunting from right to left.
- Pulmonary Embolism with pulmonary hypertension: A large pulmonary embolism can increase right ventricular pressure and, in the presence of a PFO, cause right to left shunting.
- Do Not Miss Diagnoses
- Pulmonary Arteriovenous Malformation (PAVM): Although less common, PAVMs can cause right to left shunting and should not be missed due to their potential for significant morbidity if untreated.
- Hepatopulmonary Syndrome: This condition, characterized by intrapulmonary vascular dilatations in the setting of liver disease, can cause hypoxemia and right to left shunting, making it a critical diagnosis not to miss.
- Rare Diagnoses
- Congenital heart diseases such as Ebstein’s anomaly or Tetralogy of Fallot with pulmonary atresia: These conditions can present with right to left shunting and elevated right ventricular pressures but are less common in a 56-year-old patient without a known history of congenital heart disease.
- Sinus Venosus ASD or Coronary Sinus ASD: These are less common types of atrial septal defects that can cause right to left shunting but are rare compared to other forms of ASD or PFO.