Utility of right ventricular wall thickness by CT Scan in detecting Pulmonary Arterial Hypertension among adult Filipinos using 2D echocardiography as reference standard.

Background. Pulmonary arterial hypertension (PAH) is characterized by abnormally elevated blood pressure of the pulmonary circulation. Studies have suggested that right ventricular thickness can also be used to detect the presence of PAH. RV wall thickness can be measured in CT scan studies with contrast. This study aims to determine if pulmonary hypertension can be detected and qualified using the thickness of the right ventricular wall in chest CT scan with contrast.

Method. One hundred twenty-three (123) adult subjects with CT scan of the chest with IV contrast and 2Dechocardiographic study done were included in the study. The thickness of the anterior right ventricular wall was determined in the CT scan studies. The systolic pulmonary artery pressure measurement derived by 2D-echocardiography based on the TR jet was retrieved from the subject's hospital record.

Results. There is good correlation between the RV wall thickness and systolic pulmonary artery pressure derived by 2D-echocardiography (r=0.655) p=0.000). An RV wall thickness cut-off value of 3.2 mm for normal for detecting the presence of pulmonary arterial hypertension has a sensitivity, specificity, positive predictive value and negative predictive values of 70.4%, 72.5%,66.7% and 75.8%, respectively kappa=0.426;p=0.000). There was poor agreement between groups in classifying pulmonary artery hypertension as mild, moderate or severe using different RV wall thickness cut-off values for each category (Kappa=0.368, p=0.000).

Conclusion. RV wall thickness can be used to detect the presence of pulmonary arterial hypertension; however, it cannot be used to estimate the severity of the pulmonary arterial hypertension as to mild, moderate or severe.