Clinical Analysis And Follow-up Of Transcatheter Occlusion In 940 Children With Patent Ductus Arteriosus

Objective:To assess the safety,efficacy,outcomes and complications of transcatheter Patent Ductus Arteriosus(PDA)occlusion by analyzing the clinical data of pediatric patients treated in Shandong Provincial Hospital from December 1998 to January 2020.Method:Retrospectively reviewed the clinical and follow-up data of 940 pediatric patients with PDA underwent transcatheter occlusion procedure from December 1998 to January 2020 in Shandong Provincial Hospital.All baseline demographic and clinical information were collected from electronic medical records.Contacting patients 1 year or more postoperatively by phone-call additional follow-up.Result:1.Successful occlusion of PDA was achieved in 934(934/940,99.4%)of patients.Among them,620 patients were female and 314 were male.The age ranged from 2.5 months up to 17.5 years old,with mean age of 3.56±3.16 years.The body weight ranged from 4.4kg to 73kg,with mean weight of 15.85±9.78kg.The minimum diameter of PDA measured by TTE ranged from 1.0 mm to 12.5 mm,with mean diameter of 3.36±1.60 mm.The minimum diameter of PDA measured by angiography ranged from 0.4 mm to 12 mm,with mean diameter of 2.81±1.58 mm.According to the Krichenko’s classification,the PDA was classified as type A(267/934,28.62%).type B(20/934,2.13%),type C(643/934,68.40%),type D(1/940,0.11%)and type E(6/934,0.74%)777 generation 1 occluders(777/934,83.19%)had been deployed,the diameter was ranged from 4mm to 24mm,with the mean diameter of 6.92±2.48mm.77 generation 2 occluders(77/934,8.25%)had been deployed,the diameter was ranged from 3mm to 6mm,with the mean diameter of 3.90±0.60mm.62 coils(62/934,6.64%)had been deployed,the diameter was ranged from 5mm to 6mm,with the mean diameter of 5.10±0.30mm.19 other occluders(19/934,2.02%)had been deployed.The successful occlusion rate showed no significant difference in groups divided by the characteristic of neither PDA nor patients(P>0.05)2.According to the linear regression,the minimum diameter of PDA measured by TTE were different from the value measured by angiography.The diameter measured by angiography(mm)=0.78 x the diameter measured by TTE+0.20(r=0.787P=0.000).The result could be slightly larger than the actual diameter.3.According to the linear regression,as for the first generation PDA occluder,the diameter of occluder=1.40 × PDA diameter+2.68(r=0.828 P=0.000).The size was also associated with patient’s age.Young children might have a better fit with the reasonably larger occluder.As for the second generation PDA occluder,the diameter of occluder=1.03 X PDA diameter+2.56(r=0.680 P=0.000).4.Complications of transcatheter occlusion occurred in 137 patients(137/934,14.67%),including 5 severe complications(5/936,0.54%),26 major complications(26/936.2.78%)and 106 mild complications(106/934,11.35%).No death occurred during the full period.Occluder dislocation occurred in 2 patients.Emergency surgeries were administrated to retrieve the occluder.Occluder displacement occurred in 1 patient and resulted in aortic relatively stenosis.The patient got conservative treatment and was still under routine clinical visit.Rupture of tricuspid chordae tendineae and secondary tricuspid regurgitation occurred in 2 patients.Both of them underwent surgical repairs and recovered well.Major complications including thrombocytopenia(15/934,1.61%),vessel complications(8/934,0.86%),junctional rhythm(2/934,0.21%),and secondary acute mechanical hemolysis caused be resident shunt(1/934,0.11%).1 patient with pseudoaneurysm and 1 patient with external iliac arteriovenous fistula underwent surgery repair.1 patient with resident shunt underwent another transcatheter occlusion.Other patients with major complications were recovered after conservation treatment except Mild complications including resident shunt(105/934,11.24%)and hematoma at puncture position(1/934,0.11%).The diameter of resident shunt was up to 2.1mm and all of them naturally disappeared in 6 month.The complication rate was different in ages and bodyweights(P<0.05).Patients aging under 6 months,6～12 months,1～3 years and 3～6 years had the major complication rate of 10%,7.41%,4.76%and 2.21%.No major complications occurred in patients above 6 years old.Patients weighing 4～8 kg and 8～15 kg had the major complication rate of 11.58%and 4.20%.Only 1 case of major complication occurred in a patient weighing 15kg.5.Low bodyweight(P=0.000),large PDA diameter(P=0.001)and pulmonary artery hypertension(P=0.000)were risk factors of resident shunt.The OR of Patients weighing 4～8kg and 8～15kg opposite to patients with bodyweight over 15kg was 5.27 and 2.39 The OR of combination of PAH and large PDA diameter was 1.61 and 1.36.6.Postoperative fever(P=0.000),resident shunt(P=0.001),large occluder size(P=0.005)were risk factors of thrombocytopenia.The OR of Postoperative fever,resident shunt and large occluder size was 13.37,12.71,2.04.7.Follow-up data was available in 33.09%of enrolled patients.The postoperative follow-up time ranged from 1 month to 18 years with the median of 12 months.The follow-up rates were 82.76%,83.16%,38.64%,41.46%,13.71%for patients underwent the occlusion in 1 year,]～2 years,2～3 years,3～5 years and above 5 years.No mid-long-term complication after 1 week postoperatively was observed during the follow-up period8.The enlargement of left atrium was more significant in patients under 1 year old(P<0.05).The enlargement of left ventricle was more significant in patients under 1 year old and patients above 12 years old(P<0.05).The recovery rate of both left atrium and left ventricle showed no difference among all age groups in 24 hours postoperatively.There is a significant decreasing of both left atrial and ventricular size in 24 hours postoperatively.A quick recovery can be observed in the first month postoperatively.The dimension of left atrium would be slightly higher to normal range in 1 month and the dimension of left ventricle would be in normal range in the same time.About 45%of patients would have a regular sized atrium and over 85%of patients would have a regular sized ventricle in the first year postoperatively.Furthermore,the relative size and recovery rate also showed no difference among all age groups(P>0.05).Conclusion:1.The success rate of transcatheter occlusion in 940 children with PDA in our center is 99.4%and it is not associated with age or bodyweight.Meanwhile,the severe complication rate is 0.54%with no death of complications occurred.It presents that transcatheter occlusion in children with patent ductus arteriosus has a high success rate with low complication rate and should be considered as the first choice for treatment.2.The diameter of PDA measured by TTE is linear positive correlated with the diameter measured by angiography.It’s an efficient way to assess the condition of PDA while the measured diameter is commonly slightly larger.3.The diameter of occluder is linear positive correlated with the diameter of PDA.As for the first generation of PDA occluder,the diameter of occluder=1.40×PDA diameter+2.68.As for the second generation PDA occluder,the diameter of occluder=1.03 X PDA diameter+2.56.4.The total complication rate is 14.67%while the severe and major complication rate is 3.32%.No emerging complication after 1 week postoperatively has been observed.The complication of transcatheter PDA occlusion includes occluder dislocation or displacement,rupture of tricuspid chordae tendineae,thrombocytopenia,pseudoaneurysm,thrombosis,junctional rhythm,hemolysis,resident shunt and hematoma.Occluder dislocation and rupture of tricuspid chordae tendineae should be treated by surgery in time.Low bodyweight,large PDA diameter and pulmonary artery hypertension are risk factors of resident shunt.Postoperative fever,resident shunt,large occluder size are risk factors of thrombocytopenia.5.The complication rate presenting a rising trend as age and bodyweight decreasing.Comparing with patients above 3 years old,the complication rate is as high as 3.3 times in those aged under 1 year old.Patients weighing 4～8kg has a 2.8 times higher complication rate to patients weighing 8-15kg.Patients younger than 1 year old or lighter than 8kg should delay the schedule for transcatheter occlusion under the regular assessment if there is no emergency health condition.6.The size of left atrium and left ventricle is significantly enlarged before the occlusion.There is a significant decreasing of both left atrial and ventricular size in 24 hours postoperatively.The dimension of left atrium would be slightly larger to normal range in 1 month and the dimension of left ventricle would be in normal range in the same time.Nearly half of patients would have a regular sized atrium and most of patients would have a regular sized ventricle in the first year postoperatively.