What is the best method to diagnose pulmonary hypertension?

Cardiac catheterization is considered the gold standard for diagnosing pulmonary hypertension as it directly measures the pressures within the pulmonary arteries. This invasive procedure provides accurate measurements of pulmonary artery pressures, cardiac output, and wedge pressures, helping to differentiate between different types of pulmonary hypertension and assess the severity of the condition.

While a 2D echocardiogram can support the diagnosis by suggesting elevated pulmonary pressures through indirect measures such as right ventricular size and function, the definitive diagnosis and quantification of pulmonary hypertension require cardiac catheterization. Thus, confirming the echocardiographic findings with cardiac catheterization ensures the accuracy of the diagnosis, especially in complex cases.

The other options, such as a bubble study or the presence of peripheral edema, do not provide a direct measurement of pulmonary artery pressures and therefore cannot definitively diagnose pulmonary hypertension. A bubble study can be useful in evaluating for right-to-left shunts but is not specific to pulmonary hypertension. Peripheral edema is a symptom that can accompany various conditions, including heart failure, and is not specific enough to confirm a diagnosis of pulmonary hypertension on its own.