Radiofrequency Catheter Ablation of Mahaim Tachycardia in Adult Patients

Mahaim pathways causing reentrant tachycardia are rare but potentially dangerous arrhythmia. Catheter ablation is the de�nitive treatment option for individuals with this kind of tachycardia. Objective: To evaluate the e�cacy and safety of radiofrequency catheter ablation of mahaim tachycardia in adult patients. Methods: A retrospective study investigated total of 40 adult patients referred to the Cardiac Electrophysiology Department of Hayatabad medical Complex th st Peshawar from 4 January 2017 to 21 September 2022 were enrolled. Patient's age (20-68 years) of both male and female genders referred for radiofrequency ablation of mahaim tachycardia were studied. The tachycardia was invariably antidromic, resulting from anterograde conduction via the Mahaim pathway. All the cases were followed for complications. Results: The overall mean age was 43.60 ± 12.4 years. The mean ablation and �ouro time was 9.44± 6.93 minutes and 20.64 ± 9.77 minutes respectively. Hypertension and diabetes were found in 11 (27.5%) and 6 (15%) patients respectively. The successful ablation was achieved in 31 (77.5%) patients whereas 1 case was abandoned. During follow-up, one patient developed femoral hematoma as a complication. Typical Atrioventricular nodal reentry tachycardia (AVNRT) and atrial �brillation were other tachycardia found in 3 (7.5%) and 4 (10%) respectively. The incidence of congenital anomalies such as ASD Secundum, HOCM, DCM, and Ebstein Anomaly was 2 (5%), 1 (2.5%), 1 (2.5%), and 1 (2.5%) respectively. Conclusion: The present study found that Radiofrequency ablation is effective and safe for treating Mahaim tachycardia. The success rate of RFA was 77.5%.


R E S U L T S
Additionally, no substantial indication of reversing conduction has been found in Mahaim pathways.Therefore, the present study aimed to evaluate the e cacy and safety of Mahaim tachycardia radiofrequency catheter ablation in adult patients.
The incidence of congenital anomalies such as ASD Secundum, HOCM, DCM, and Ebstein Anomaly was 2 (5%), 1 (2.5%), 1 (2.5%), and 1 (2.5%) respectively.Non irrigated APT, irrigated cool ow, and non-irrigated Therapy were the different catheters used in 37 (92.5%), 1 (2.5%), and 2 (5%) respectively.Tachycardia was induced after ablation in 10 (25%) patients.Details of congenital anomalies, catheter, and ablation in tachycardia, are shown in Table 3.  [11].Patients (<20 years or >68 years) with no signs and symptoms of tachycardia were excluded.All the patients experienced symptoms and either had tachycardia or produced during an electrophysiological examination.The tachycardia was invariably antidromic, resulting from anterograde conduction via the Mahaim pathway.All the cases were followed for complications.Following providing informed written consent, all patients received electrophysiological study and ablation.Prior to intervention, all antiarrhythmic medications had been discontinued.Diazepam and diamorphine were used to sedate the patients.After con rmation of Mahaim tachycardia, a large-tip de ectable electrode catheter with a 4 mm distal electrode was inserted into the femoral vein to map the tricuspid annulus.Target ablation sites were chosen based on the existence of distinct Mahaim potentials, which mimicked signals obtained from the His bundle electrode but at different locations.Moreover, atrial pacing and Mahaim tachycardia might disassociate such p o t e n t i a l s f r o m t h e H i s b u n d l e e l e c t r o g r a m .Radiofrequency radiation was carried for up to three and a half minutes, but if no impact was noticed after 15 seconds, the supply was halted.For statistical analyses, Stata 15.1 was utilized.Data were displayed as percentages (%) or as the median (range or quartiles).The 2-test or Mann-Whitney test was used to compare groups.P<0.05 was found to be signi cant.
The overall mean age was 43.60 ± 12.483 years with an age range 20-68 years.Of the total 40 patients, there were 28 (70%) male and 12 (30%) females.The mean ablation and ouro time was 9.44 ± 6.93 minutes and 20.64 ± 9.77 minutes respectively.Hypertension and diabetes were found in 11 (27.5%) and 6 (15%) patients respectively.The successful ablation was achieved in 31 (77.5%)patients whereas 1 case was abandoned.During follow-up, 1 patient developed femoral haematoma as a complication.Typical Atrioventricular nodal reentry tachycardia (AVNRT) and atrial brillation were other tachycardia found in 3 (7.5%)and 4 (10%) respectively.Baseline characteristics of patients are shown in Table 2.  et al., and Soares et al., reported that "successful ablation of an atriofascicular bre by radiofrequency energy application on the ventricular side of the tricuspid annulus at a place where catheter tip pressure produced serendipitous elimination of pre-excitation" [17,18].Moreover, it has also been proposed that catheter-induced The present study found that Radiofrequency ablation is effective and safe for treating Mahaim tachycardia.Additional auxiliary pathways appear to be frequent in patients with this kind of tachycardia .The success rate of RFA was 77.5%.The detection of Mahaim potentials reveals the majority of pathways, allowing for effective ablation and the elimination of this tachycardia.

Table 1 :
Age-wise distribution of patients

Table 3 :
Details of congenital anomalies, catheter, and ablation in tachycardia

Table 2 :
Baseline characteristics of patients