| Objective: In some patients with chronic mountain sickness(CMS),the main pulmonary artery(MPA)is dilated.To a certain extent,MPA dilation can reflect the pulmonary hypertension.The untreated pulmonary hypertension can progress fast.Usually three years after the diagnosis will progress to ventricular failure and threaten patients’ life.This program uses the advantages of CMR in cardiac examination to explore the changes of right ventricular structure and function in patients with CMS,which MPA is dilated.Early to discovery and intervention the right heart changes can prevent right heart failure.Methods: 40 cases of male volunteers who were clinically diagnosed as CMS from December 2015 to December 2017 were collected.CMR scans were performed on all subjects using the Philips Achieva 1.5T superconducting nuclear magnetic resonance scanner and the acquired images were post-processed and analyzed.One physician measured and calculated the parameters of the right heart’s structure and function,while another physician measured the MPA diameter(d MPA).The patients(d MPA>30mm)were included in the MPA-dilated group(n = 21;mean age = 47.71 ± 9.53 years,mean living height = 3681.95 ± 261.95 m),the rest patients(d MPA ≤ 30 mm)were included in the control group(n = 19,mean age = 43.05 ± 9.33 years,average living height = 3668.42 ±312.78m).The parameters form the two physicians were independent go through the t-test to find the difference of the right heart’s structure and function related parameters from the two patients group.Results:(1)Index of the right heart structure: The value of RVLW,RVAW,RVESTD,and EDMM in the MPA-dilated group were 5.45±0.97 mm 、 4.90±0.99 mm 、33.23±6.48mm、47.91±14.42 g respectively.The control group were 3.56±0.71mm、3.24±0.61mm、25.71±4.43mm、35.92±6.08 g respectively.(2)Index of the right heart function: The value of TAPSE in the MPA-dilated group was 16.95±6.88 mm.The control group was 25.98±4.21 mm.Compared with the control group,RVLW,RVAW,RVESTD and RVEDMM in MPA-dilated group were higher,TAPSE was significantly lower(P <0.05).Conclusion: Some CMS patients’ MPA was dilated,and the structure and function of right heart in these patients were changed.Besides,the structure of right heart changes obviously and the function changes slightly in these patients compares to that in MPA normal group.CMR can detect these changes early and assess it effectively,which has practical value in clinic. |
