Pulmonary hypertension due to left heart disease with pulmonary arterial wedge pressure <= 15mmHg

Background. Pulmonary hypertension due to left heart disease (PH-LHD) is the most prevalent type of pulmonary hypertension (PH). The hemodynamic diagnostic standard of pulmonary arterial wedge pressure (PAWP) >15mmHg that is traditionally recommended by guidelines is being challenged. Methods. To address this problem, we analyzed the data of 154 patients with PHLHD admitted to our center from April 2013 to March 2018. Pharmacological or nonpharmacological treatment of underlying left heart disease was offered to all 154 patients. Results. In total, there were 24 patients (15.6%) with PAWP =15mmHg. Comparison of echocardiography and right heart catheterization parameters between the two groups (PAWP >15mmHg and PAWP =15mmHg) showed that the group with PAWP =15mmHg had smaller left ventricular diameter, higher cardiac output, lower pressure and higher oxygen saturation in the pulmonary artery, right atrium, right ventricle, and superior vena cava. No significant difference was found regarding dilated cardiomyopathy, diabetesmellitus, hypertension, atrial fibrillation, and left heart valvular disease, but a significant difference was found for coronary heart disease (higher morbidity in group with PAWP =15mmHg) between the two groups. Conclusion. We found that 15.6% of the patients with PH-LHD under pharmacological or nonpharmacological treatment had PAWP =15mmHg. These results suggest that the diagnostic criterion of PAWP and the characteristics for this group of patients should be further investigated.