RV Failure in Pulmonary Hypertension Amplified by Secondary Hemochromatosis

Introduction A 38-year-old female with history of beta thalassemia requiring several blood transfusions yearly presented with fatigue and dyspnea. Case Report Transthoracic echocardiogram (TTE) revealed severe RV dysfunction and severe tricuspid regurgitation (figure 1) with elevated estimated RV systolic pressure. A presumptive diagnosis of right heart failure secondary to PH was made and the patient was empirically started on PH-specific therapy. The PH team was consulted. Careful review of the TTE revealed several features that were inconsistent with a RV failing due to high afterload. Systolic interventricular septal flattening occurs when the RV is being subjected to a high pulmonary vascular resistance (PVR). Notching of the RV outflow tract (RVOT) Doppler and earlier time to peak velocity (acceleration time) occurs with high pulmonary arterial impedance. None of these features were present on TTE. Right heart catheterization was confirmatory, demonstrating right atrial pressure 19 mmHg, pulmonary artery pressure 33/22 mmHg, wedge pressure 8 mmHg, PVR 4 Woods units, and cardiac index 2.6 L/min/m2. The degree of RV dysfunction was felt to be out of proportion to the degree of PH. Taken together with frequent premature ventricular contractions, cardiac MRI was performed to evaluate for another etiology of RV failure. T2 measurements were consistent with cardiac iron overload (figure 1). Serum ferritin was 26,713 ng/mL. Secondary hemochromatosis was diagnosed due to frequent blood transfusions for thalassemia management. The patient underwent IV iron chelation therapy with improvement in RV function and tricuspid regurgitation. Summary The severity of RV failure should be interpreted relative to the severity of PVR elevation in PH. Septal position and RVOT Doppler assessment on TTE can provide valuable insight into the physiology and mechanism of right ventricular failure. This case demonstrates this application, with subsequent use of MRI to confirm a rare diagnosis of RV failure due to secondary hemochromatosis