Correct!
3. Right heart catheterization
Given the clinical context and the transthoracic echocardiographic findings, pulmonary hypertension is likely, but right heart catheterization is required to confirm this diagnosis, and that diagnosis should be established or excluded sooner rather than later. A repeat transesophageal echocardiogram could be of benefit if the findings at transthoracic echocardiography were unclear, the transthoracic echocardiogram was technically limited, or an intracardiac shunt was suspected, but these considerations are not relevant to this patient. As noted previously, in the context of systemic sclerosis, the pattern of lung injury generally does not impact the course of therapy, and therefore tissue sampling is not required and may result in a greater rate of complication given the possible pulmonary hypertension. Cardiac MRI may be of benefit in patients with various cardiac diseases, including the possibility of pulmonary hypertension, and probably provides the most accurate method to assess right ventricular function and is particularly valuable when echocardiographic examinations are technically limited. Cardiac MR can provide data suggesting the presence of, and possible cause for, pulmonary hypertension, but this examination is not a substitute for the right heart catheterization confirmation of pulmonary hypertension.
Right heart catheterization showed a mean pulmonary arterial pressure of 34 mmHg, and pulmonary capillary wedge pressure of 8 mmHg, and a pulmonary vascular resistance of 4.8 Wood units. The patient was continued on mycophenolate mofetil and oxygen therapy and did well for three months, after which she presented with worsening dyspnea, now at rest, new lower extremity edema, and worsening hypoxemia. Enhanced thoracic CT (Figure 2) was performed.
Figure 2. Contrast-enhanced CT angiography. Upper panels A-D: Representative static images. Lower left: video of CT angiography in lung window. Lower right: video of CT angiography in soft-tissue windows.
Which of the following represents the most likely diagnosis for this patient? (Click on the correct answer to proceed to the eighth and final page)