What defines pulmonary hypertension in terms of mean PA pressure?

Pulmonary hypertension is defined as an increase in mean pulmonary arterial pressure. The correct threshold for diagnosis is a mean pulmonary artery pressure greater than 25 mmHg at rest. This condition is significant because it indicates that there is an increased pressure in the pulmonary circulation, which can lead to various symptoms and complications, including heart failure and reduced exercise tolerance.

Option C reflects the accepted medical criteria for pulmonary hypertension, making it the correct choice. Understanding this definition is crucial for assessing patients who may present with symptoms suggestive of pulmonary issues, enabling timely diagnosis and treatment.

The other options represent values that are lower than the established threshold and do not meet the clinical criteria for diagnosing pulmonary hypertension.