Evaluating The Incidence Of Pulmonary Vein Stenosis After Circumferential Pulmonary Vein Electrical Isolation In Atrial Fibrillation

BACKGROUD:Pulmonary venous stenosis(PVS)is one of the complications that occurred after radiofrequency ablation of atrial fibrillation(AF)but failed to attract enough attentions.Severe PVS can cause pulmonary hemodynamic disorders and eventually lead to pulmonary hypertension,and cause recurrent lung infections,pulmonary nodules,pleural effusion and other diseases.The prognosis of severe PVS is poor,and the mortality rate due to untimely treatment is high.Therefore,early diagnosis and active treatment of PVS after Circumferential Pulmonary Vein Electrical Isolation(CPVI)through postoperative imaging follow-up is important.Pulmonary vein CTA is an economical and effective method for detecting PVS.This study followed 93 patients with AF fibrillation ablation in our hospital by pulmonary vein CTA to study the incidence of PVS and the characteristics of narrow pulmonary veins.OBJECTIVES:This study aimed to detect the incidence of PVS in patients with AF after CPVI by CT angiography(CTA),and to evaluate the effect of radiofrequency ablation of AF on the diameter of the pulmonary vein.METHODS:93 patients with AF who underwent CPVI from 2016 to 2019 were enrolled.All patients collected baseline data,echocardiographic data and left atrium reconstruction data before ablation,including left atrium diameter,pulmonary vein shape,pulmonary vein diameter,etc.Every month after the ablation,the patient will be followed up by telephone or outpatient clinic to check for PVS symptoms such as chest tightness,chest pain,and cough.At the 1st,3rd and 6th month after operation,the routine examinations such as echocardiography and Holter were completed.In the third month,the pulmonary vein CTA examination was completed,and the pulmonary vein CTA was used to judge the occurrence of PVS after CPVI in these patients.Then using the direct contrast method and the indirect contrast method to calculate the degree of PVS,and divided it into mild stenosis(diameter reduced<50%),moderate(diameter reduced by 50%-70%),and severe(diameter reduction≥70%).Patients were divided into stenosis group and non-stenosis group according to whether there was PVS after operation.Independent sample T test and chi-square test were used to compare whether there was statistical difference in baseline data between two groups.Using univariate Logistic regression to analyze whether there are risk factors of PVS.The independent sample T test was used to analyze whether the results obtained by the direct comparison method and the indirect comparison method were statistically different.RESULTS:At present,we have found a total of 31(33.33%)patients with PVS by follow-up.According to the data obtained by direct contrast method and indirect contrast method,the incidence of PVS can be sorted as:left inferior pulmonary vein(LIPV),right inferior pulmonary vein(RIPV),left superior pulmonary vein(LSPV),right superior pulmonary vein(RSPV).The average pulmonary stenosis was ranked as:LIPV,LSPV,RIPV,RSPV.Analyzing the results obtained by the direct contrast method and the indirect contrast method,it can be seen that these two measurement methods have no statistical difference.Of all patients with PVS,only 1 patient presented with the chief complaint of cough and mild chest congestion before the examination.According to the CTA examination,the LSPV of the patient was thinner than before,and the LIPV was narrower than before and thrombosis occurred.The remaining patients did not complain of significant discomfort.During the follow-up,a total of two patients developed severe PVS,but they had no obvious symptoms and no PVS progressed during long-term follow-up.Therefore,there is no intervention was performed.Two other patients had mild PVS with pulmonary venous thrombosis,and were given anticoagulant therapy with novel oral anticoagulant for more than one month.Then the thrombus disappeared after another follow-up.CONCLUSIONS:①In this study,patients with AF have a 33.33%chance of developing PVS after CPVI,but most of them are mild stenosis with no clinical symptoms.②This study showed that the incidence of PVS is ranked as:LIPV,RIPV,LSPV,RSPV,and the mean pulmonary vein stenosis degree is ranked as:LIPV,LSPV,RIPV,RSPV.③This study suggested that both direct contrast method and indirect contrast method can be used to calculate the degree of PVS.