| Objective(s): Linear catheter ablation of the cavo-tricuspid isthmus is the most effective treatment for patients with atrial flutter and is the main ablation line after isolation of the annular pulmonary vein in patients with atrial fibrillation.The difficulty in ablating the cavo-tricuspid isthmus lies in the various anatomic structures of the cavo-tricuspid isthmus,such as the capsular bag-like depression,Eustachian ridge,and the depression between the myocardial trabeculae and the myocardial trabeculae.Therefore,this study aims to investigate the dissection of the the cavo-tricuspid isthmus in patients with atrial fibrillation and atrial flutter under the guidance of intracardiac echocardiography,in order to solve the relationship between their anatomical characteristics and ablation efficacy.Methods: This study continuously included 82 patients who underwent linear ablation of the cavo-tricuspid isthmus in the First People’s Hospital of Yunnan Province from January 2021 to December 1,2022 due to persistent atrial fibrillation,paroxysmal atrial fibrillation,and typical atrial flutter.The length of the cavo-tricuspid isthmus(at the end of the ventricular diastolic period,the distance from the Eustachian ridge to the tricuspid annular attachment point is measured on the image taken by intracardiac echocardiography)and the deepest depth were measured by the CARTO3 V6 system and intracardiac echocardiography,and the depth was divided into Straight type,Concave type,and Pouch type.The Patients were divided into two groups according to CTI length,with the long group > 35 mm and the short group ≤35 mm.According to whether there is a European flap,it is divided into a European flap group and a non-European flap group.According to whether the ablation line passed through the Pouch type of cavo-tricuspid isthmus,the part was simple group(the ablation line did not pass through the capsule type)and the complex group(the ablation line passed through the capsule type),and then the difference among the two groups of patients(such as total ablation time,total ablation AI value,total number of ablation)was analyzed.Record the total ablation AI value,total ablation time,total ablation times,etc.required for CTI ablation success.All results were statistically significant with P<0.05.Results: All 82 patients achieved acute bidirectional conduction block of the isthmus of the tricuspid valve,without cardiac tamponade,steam pop,femoral arteriovenous fistula,pseudoaneurysm,thrombosis and embolism.The total ablation AI values,total ablation time and total ablation times of different types of isthmus were as follows: 20 cases of Straight type,10998(7189-15356),473(379-559)s,24(18-42)times,42 cases of Concave type,.10911(7551-15479),410(316-616)s,30(18-39)times,20 cases of Pouch type 11993(9433-15808),523(383-681)s,31(22-40)times.The total ablation AI values,total ablation time and total ablation times of the long and short groups were as follows: 42 cases 11656(9011-15947),463(336-646)s,30(22-42)times in the long group,and 40 cases 11135(7411-15111),494(338-569)s,27(18-39)times in the short group.The total AI value,total ablation time and total ablation times with or without European valve were as follows: 25 cases12545(7666-16948),527(302-697)s,33(22-43)times with European valve,and 57 cases without European valve 10889(8659-14891),488(343-543)s,27(20-39)times.The proportion of flat type was higher in the short group than in the long group(34.0% VS 9.4%,P=0.004);The proportion of flat type in the group without European valves was higher than in the European valve group(31.6% VS 8.0%,P=0.044).There was no statistically prominent difference in the ablation time required between the long and short groups(463(336-646)s VS 494(338-569)s,P=0.74).The complex group had higher total ablation AI values(16396±5587 VS 11401±3528,P=0.024),longer total ablation time(717±310s VS 502±151s,P=0.049)and more total ablation times(42±13 VS 28±8,P=0.009)than the simple group.Conclusion(s): Linear ablation of the cavo-tricuspid isthmus guided by intracardiac echocardiography can better observe the anatomical structure of the cavo-tricuspid isthmus,and the capsular cavity-like depression structure can be intuitively found.The cavo-tricuspid isthmus anatomy of the pouch type can prolong the ablation AI value,ablation time,and number of ablation times,may improve ablation success rate.it is reasonable to adjust the linear ablation strategy according to the specific anatomical structure of the cavo-tricuspid isthmus(eg,pouch bag)under the guidance of intracardiac echocardiography. |
PDF Full Text Request