Follow-up Study On The Exercise Capacity And Ventilatory Efficiency In The Patients With Pulmonary Thromboembolism

[Objective] To study the changes of Ventilatory efficiency and exercisecapacity during Cardiopulmonary Exercise Testing (CPET) in patients withpulmonary thromboembolism after anticoagulant therapy from2weeks to6months.[Methods] Cardiopulmonary exercise testing,pulmonary function testand arterial blood gas analysis was performed in30patients with PTE afteranticoagulant therapy2weeks (early phase) and6months after (late phase).In addition,another30healthy volunteers (the control group) were given thesame tests.[Results](1) There were no significant differences in age[(57.47±11.33)vs.(60.27±6.23)years], gender and BMI[(24.02±2.61) vs.(23.85±2.94)kg/m2,P>0.05].(2) The resting parameters from ABG and PFT， such as PaO2,FVC%pred, FEV1%pred, MVV%pred, TLC%pred, DLCO%pred in the PTEgroup after treatment of2weeks and6months both were significantly lowerthan those of the control group（P<0.05），thus, P(A-a)O2was higher than thatin the control group（P<0.01）.(3) After treatment for6months, FVC%pred improved obviously in the PTE group （P<0.01）, other resting parameters, such as PaO2, FEV1%pred,MVV%pred, TLC%pred, DLCO%pred had no significant statistical differencesthan the early phase（P>0.05）.(4) In the two groups of PTE patients, AT, AT-VO2%pred, peak LOAD,peakLOAD%pred, peak VO2, peakVO2%pred were significantly lower thanin the control group（P<0.01）. While other parameters such as lowestVE/VCO2, lowestVE/VCO2%pred, AT-VE/VCO2, AT-VE/VCO2%pred,VE/VCO2slope, VE/VCO2slope%pred were significantly higher than in thecontrol group（P<0.001）.(5) After treatment for6months, peak LOAD, peak LOAD%pred, peakVO2, peak VO2%pred increased significantly in the PTE group (P <0.01), inaddition, lowestVE/VCO2and lowestVE/VCO2%pred decreased significantly（P=0.001）, other parameters such as AT, AT-VO2%pred, AT-VE/VCO2,AT-VE/VCO2%pred, VE/VCO2slope or VE/VCO2slope%pred had nosignificant statistical differences than the early phase（P>0.05）（6）In PTE group, the raised of PeakVO2%pred from2weeks to6months had a correlation with the decreased of lowestVE/VCO2%pred（r=0.639，p＜0.001）but not the increased of FVC%pred （r=0.058，p=0.769）.[Conclusion] After regular anticoagulation for6months in patients withacute pulmonary thromboembolism,the exercise capacity. Improvedsignificantly and the ventilation efficiency may improved gradually,but all of themcould not fully recover.