Relationship between pulmonary arterial hypertension and galectin in patients with human immunodeficiency virus infection

Introduction: The rate of pulmonary arterial hypertension in patients with human immunodeficiency virus (HIV) infection is 2500 times greater than in the general population. In patients with unexplained dyspnea there is an indication for echocardiography to detect HIV-related cardiovascular complications. Previous studies have shown that galectin-3 levels increase in HIV infections. At the same time, there were studies in which high levels of Galectin-3 were detected in patients with high pulmonary artery pressure. Our study was planned to determine the predictive value of serum Gal-3 level for PAH presence in HIV-infected adults with dyspnea by evaluating estimated systolic pulmonary artery pressure, right ventricular functions and right ventricular strain findings via echocardiography. Materials and Methods: The study was a single-center, prospective trial. Written consents were taken from all the 30 adults with HIV infection and dyspnea, who meet the inclusion criterias and have no other etiology that may define their dyspnea. All study population underwent transthoracic echocardiography. Blood samples were taken and Galectin-3 was studied. Participants were grouped due to the mean Gal-3 level. Participants' estimated systolic pulmonary artery pressure were calculated over tricuspid regurgitant flow maximum velocity. Values over 30 mmHg were associated with an elevated systolic pulmonary artery pressure. Results: 9 (30%) of the participants were female and 21 (70%) was male. Mean age of the participants was 46,27±14'. Mean TAPSE was 20,01±3,4 mm, mean tricuspid lateral annulus s' velocity was 13,45±2,21 cm/sn, mean RVFAC was %38,12±7,72, mean RVSTRAIN was -23,26±3,6. Mean tricuspid regurgitant flow maximum velocity was 2,32±0,38 m/sn. Mean estimated systolic pulmonary artery pressure was 27,2±7,6 mmHg. Mean Galectin-3 level of the participants was 17,12±5,32 ng/ml. This value was found to be higher than mean Gal-3 level of healthy population. 3 (10%) of the participants had an estimated systolic pulmonary artery pressure of over 30 mmHg. Mean Galectin-3 level of these 3 participants was 20,26±3.41 ng/ml, mean TAPSE was 19,33±2.51, mean S' 14,26±2.73, mean RVFAC as 40,93±11.86, mean RVSTRAIN was -25,6±3.7. When groups were compared due to Gal-3 levels, there was not a significant difference between two groups for RV systolic function parameters. Participants with higher Gal-3 levels were older. HIV infected patients with dyspnea was evaluated in our study. Mean Gal-3 value was found to be higher than mean Gal-3 level of healthy population. There were studies which show the relationship between Gal-3 and pulmonary arterial hypertension. Also some studies blamed Gal-3 in pulmonary arterial hypertension pathogenesis. Is high Gal-3 level an early finding in this group of patients without significant change in pulmonary arterial pressure and right ventricular function? Echocardiographic follow-up parameters of these cases with high and low Gal-3 levels will help to test this hypothesis. We used transthoracic echocardiography for the diagnosis of PAH. Right heart catheterization was not administered. Right heart catheterization is the gold standard method for assessment of pulmonary artery pressure and helps in the treatment approach of the cases with high pulmonary artery pressure. Due to the low proportion of HIV in the etiology of pulmonary hypertension, we can assume that the study population is limited. Randomized studies with larger case populations and different galectin-3 cut-off values may provide different information about the relationship between Galectin-3 levels and pulmonary hypertension in HIV.