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DOI 10.11603/ijmmr.2413-6077.2021.1.12258

RADIATION EXPOSURE IN ACCESSORY PATHWAY ABLATION 
PROCEDURES IN CARDIAC ELECTROPHYSIOLOGY: A RETROSPECTIVE 
ANALYSIS

*M. Ali1,2, B. Banavalikar1, M.K. Ghadei1, A. Kottayan1,  
D. Padmanabhan1, J. Shenthar1

1 – DEPARTMENT OF CARDIAC ELECTROPHYSIOLOGY, SRI JAYADEVA INSTITUTE OF CARDIOVASCULAR 
SCIENCES AND RESEARCH, BANGALORE, INDIA

2 – DEPARTMENT OF CARDIOLOGY, SHER-I-KASHMIR INSTITUTE OF MEDICAL SCIENCES,  
SRINAGAR, KASHMIR, INDIA

Background. Radiofrequency catheter ablation (CA) has been the treatment of choice in patients with 
accessory pathway (AP)-mediated tachycardias. Most of these procedures are done under fluoroscopic guidance, 
leading to significant radiation exposure to the patient and the laboratory personnel. In this analysis, we have 
looked at the amount of radiation exposure in AP CA procedures performed without the support of a three-
dimensional electroanatomic mapping system. We have analyzed changes in exposure indices over the study 
period and the impact of change in fluoroscopy frame rate (FFR).

Objectives. The objectives of this study are to quantify radiation exposure in accessory pathway ablation 
procedures; to analyze the radiation exposure trend over time; and to evaluate the effect of fluoroscopy frame 
rate reduction on the radiation exposure indices in these procedures.

Methods. All the AP ablation procedures performed at our institute from January 2016 to December 2019 
were retrospectively analyzed. The collected data were age, sex, location of APs based on successful site of ablation 
on fluoroscopy, procedure time, fluoroscopy time, and dose-area product (DAP). Effective dose (ED) was estimated 
from DAP. The data of procedures performed before January 2018 (“pre” group) were compared with those of 
the procedures performed after that date (“post” group). Pre-group procedures were performed at an FFR of 7.5 
frames per second (fps), and post-group procedures – at an FFR of 3.75 fps.

Results. The total number of procedures included in the analysis was 635. The mean age of the patients was 
39±14 years, and 401 of them (63%) were males. The most common location of the APs was left lateral (38%). 
Procedure time and radiation indices showed a significant decrease over the study period (p < 0.001). Post group 
procedures had significantly shorter procedure time and lower radiation exposure than pre group procedures. 

Conclusions. A decrease in the FFR was associated with a significant reduction in radiation exposure in AP 
ablation procedures

KEYWORDS: accessory pathway; catheter ablation; dose-area product; fluoroscopy time; radiation 
exposure.

Introduction

International Journal of Medicine and Medical Research 
2021, Volume 7, Issue 1, p. 28-34
copyright © 2021, TNMU, All Rights Reserved

*Corresponding author: Dr. Muzaffar Ali, Department of Car-
diology, SKIMS, Srinagar, Kashmir, India. Email: dralimuzaf-
far@gmail.com

The ablation of accessory pathways (AP) 
using radiofrequency energy was first intro-
duced by Borggrefe and colleagues in 1987 
when they ablated a right-sided accessory 
pathway for the first time in humans using 
radiofrequency energy [1]. Since then, radio-
frequency ablation has been the treatment of 
choice in patients with accessory pathway-
mediated tachycardias [2,3]. Although radio-
frequency ablation for AP-mediated tachy-
cardias is a highly efficacious and safe treatment 

option, some of the adverse effects of this 
procedure are not because of the procedure 
itself but because of the ionizing radiation used 
to visualize the catheters during the procedure. 
Ionizing radiation exposure affects the patient 
and the laboratory personnel because of the 
fluoroscopic imaging used during cardiac 
electrophysiology (EP) procedures. 

The ionizing radiation exposure can cause 
long-term hazardous effects, including malig-
nancy, cataract formation, thyroid dysfunction, 
dermatitis, germline mutations, etc. This is due 
to double-strand breaks induced in the DNA 
backbone brought about by the free radicals 

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generated due to the exposure of ionizing 
radiations [4]. 

The hazard of radiation exposure increases 
with the higher radiation dose, which in turn 
increases with the longer duration of EP pro-
cedure for the patient and increase in the 
number of EP procedures for the laboratory 
staff. Thus, it is essential to evaluate the benefit 
of the intended EP procedure over the risk of 
expected exposure to ionizing radiation and 
minimize the radiation exposure levels to mini-
mum achievable levels for both the patients 
and the laboratory staff to have an overall 
beneficial outcome of the EP procedure [4].

One way to decrease radiation exposure in 
cardiac electrophysiology procedures is to use 
a lower fluoroscopy frame rate. We have pre-
viously reported of the impact of fluoroscopy 
frame rate reduction in complex catheter 
ablation procedures performed under a three-
dimensional electroanatomic mapping system 
[5]. In this study, we analyzed radiation expo-
sure indices in our laboratory’s AP ablation 
procedures. We have also analyzed the impact 
of fluoroscopy frame rate reduction on radiation 
exposure indices during these procedures. 

The objectives of this study are: to quantify 
radiation exposure in accessory pathway ab-
lation procedures; to analyze the radiation 
exposure trend over time; and to evaluate the 
effect of fluoroscopy frame rate reduction on 
the radiation exposure indices in these pro-
cedures.

Methods
A retrospective analysis of accessory path-

way ablation procedures carried out in a tertiary 
care referral institute in Southern India was 
performed. The data were collected from 
January 2016 to December 2019. The data 
available were age, sex, location of successful 
ablation, fluoroscopy time, and dose area 
product (DAP). 

Procedures without such data were exclu_
ded. Patients with multiple accessory pathways 
were also excluded from the analysis. The 
procedure time for catheter ablation procedures 
was defined as the time from the administration 
of a local anesthetic agent to removing ca-
theters from the patient’s body. Our institute 
has an ongoing cardiac electrophysiology 
fellowship program, and the fellows assist in all 
the catheter ablation procedures performed in 
our laboratory. Four physicians performed the 
catheter ablation procedures with an experience 
of 21, 11, 6, and 4 years in interventional 

electrophysiology. All the catheter ablation 
procedures were performed without three-
dimensional electroanatomic mapping. The 
institute has an active EP fellowship program 
running since 2009, and the fellows assist in all 
the procedures performed in the laboratory. 
The laboratory is equipped with the Philips 
Allura Xper FD 10 system (Philips Healthcare, 
the Netherlands), and all the procedures were 
performed using the same system.

The fluoroscopy frame rate used in the 
laboratory was 7.5 fps before February 2018. 
From the beginning of February 2018, fluo-
roscopy at 3.75 fps have been used. The location 
of the accessory pathways was determined by 
the location of successful ablation in the left 
anterior oblique (LAO) projection, as shown in 
Figure 1.

The Effective Dose (ED, mSv) was estimated 
from DAP provided by the X-ray system by 
multiplying DAP with the following conversion 
factors depending on the age of the patient: 
5-10 years of age: 1.0; 10-15 years of age: 0.6; 
15-20 years of age: 0.4; adult females: 0.28 and 
adult males: 0.2. Lifetime attributable risk (LAR) 
of cancer incidence and mortality was derived 
from the ED by multiplying it with 0.0001/mSv 
(the standardized BEIR VII conversion factor) 
[5].

The data were summarized using standard 
descriptive statistics and presented as the 
arithmetic means with standard deviation (SD) 
or median with interquartile range, as appro-
priate. Nonparametric statistical tests like the 
Kruskal-Wallis test and the Mann-Whitney U 
test were used to analyze the procedure time 
and radiation exposure parameters over the 
study period and the effect of fluoroscopy fra-

Fig. 1. Location of accessory pathways as seen on a left ante-
rior oblique (LAO) projection.
HB: His Bundle; LAL: left anterolateral; LL: left lateral; LPL: left 
posterolateral; LP: left posterior; LPS: left posteroseptal; RPS: 
right posteroseptal; RP: right posterior; RPL: right posterolat-
eral; RL: right lateral; RAL: right anterolateral; RA: right ante-
rior; RAS/PH: right anteroseptal/para-Hisian; MS: midseptal.

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me rate over various parameters, respectively. 
The level of significance was fixed at p<0.05.

Institutional ethical committee approval 
was not applied for this retrospective analysis. 
Informed consent was obtained from all pa-
tients before the procedures, which included 
the clause that their data could be used for 
scientific purposes in the future.

Statistical Package for the Social Sciences 
(SPSS), version 20, was used to perform sta-
tistical analysis.

Results
Six hundred and thirty-five pathway ablation 

procedures were included in the analysis. The 
mean age of the patients was 39±14 years. The 
mean age of male patients (n=401; 63% of the 
total) was 39±13 years, and female patients 
(n=234; 37% of the total) were 40±14 years.

The location of the accessory pathways and 
the associated procedure time and radiation 
indices are presented in Table 1. The number 
of the pathways ablated from the left side was 

372 (58.6%), and that from the right were 263 
(41.4%). The most common location of the 
ablated pathways was left lateral, which was 
38.4 % of all the pathways, and the second most 
common location was right posteroseptal, 
which was 27.2% of all the pathways. The least 
common location of accessory pathways was 
mid septal (0.3%) followed by right anterolateral 
(0.5%) and right anterior (0.5%) locations.

Trends in various indices over the study 
period are shown in Table 2. 15% (96) of all the 
procedures were performed in 2016. In the 
years 2017, 2018, and 2019 the proportion of 
the procedures performed was 23% (149), 31% 
(196), and 31% (194), respectively.

Trends in the indices before (pre group) and 
after (post group) the change in fluoroscopy 
frame rate are shown in Table 3. 41% of the 
procedures (n=260) were performed under 
fluoroscopy frame rate of 7.5 fps, and 59% of 
the procedures (n=375) were performed under 
fluoroscopy frame rate of 3.75 fps.

Discussion

Table 1. Procedure time and radiation indices based on the successful location of ablation  
on fluoroscopy in left anterior oblique projection

Pathways No. (%) ProcedureTime (min)
Fluoroscopy
Time (min)

DAP
(cGy/cm2)

ED
(mSv)

LAR,
%

LAL 18 (2.8) 55 (45-98) 10 (8-14) 538 (313-706) 1.1 (0.8-1.5) 0.01 (0.008-0.02)
LL 244 (38.4) 55 (45-75) 11 (8-17) 796 (480-1343) 1.8 (1.1-3.1) 0.02 (0.01-0.03)
LPL 34 (5.4) 55 (44-81) 12 (7-17) 787 (483-1884) 1.9 (1.0-4.1) 0.02 (0.01-0.04)
LP 22 (3.5) 58 (48-66) 13 (7-19) 1014 (456-1570) 2.3 (1.1-3.5) 0.02 (0.01-0.03)
LPS 54 (8.5) 80 (55-106) 20 (10-29) 1637 (795-2384) 3.6 (1.8-5.3) 0.04 (0.02-0.05)
RPS 173 (27.2) 60 (43-90) 13 (8-19) 988 (465-1609) 2.1 (1.1-3.6) 0.02 (0.01-0.04)
RP 12 (1.9) 60 (36-94) 15 (7-26) 1372 (411-3420) 2.7 (0.8-8.2) 0.03 (0.01-0.08)
RPL 24 (3.8) 69 (55-100) 19 (11-26) 1220 (738-2448) 3.5 (1.8-5.5) 0.04 (0.02-0.06)
RL 27 (4.3) 90 (70-120) 27 (15-43) 1534 (848-2529) 3.6 (1.7-7.5) 0.04 (0.02-0.08)
RAL 3 (0.5) 105 (45-105) 17 (11-17) 701 (288-701) 2.8 (0.6-2.8) 0.03 (0.005-0.3)
RA 3 (0.5) 65 (60-65) 21 (18-21) 1596 (723-1596) 4.4 (1.5-4.4) 0.04 (0.01-0.4)
AS/PH 19 (3.0) 65 (46-80) 15 (7-18) 555 (441-862) 1.2 (0.9-2.3) 0.01 (0.01-0.02)
MS 2 (0.3) 100 (45-100) 21 (7-21) 1549 (377-1549) 3.1 (0.8-3.1) 0.01 (0.007-0.01
Total 635 (100.0) 60 (45-90) 13 (8-19) 889 (488-1660) 2.1 (1.1-3.7) 0.02 (0.01-0.04)

Notes: LAL: left anterolateral; LL: left lateral; LPL: left posterolateral; LP: left posterior; LPS: left posteroseptal; RPS: right pos-
teroseptal; RP: right posterior; RPL: right posterolateral; RL: right lateral; RAL: right anterolateral; RA: right anterior; RAS/PH: 
right anteroseptal/para-Hisian; HB: His bundle; MS: midseptal.

Table 2. Change in procedure time and radiation indices over the study period

Year Number Procedure  time (mins)
Fluoroscopy  
time (mins) DAP (cGy/cm

2) ED (mSv) LAR, %

2016 96 75 (51-94) 19 (11-25) 1254 (751-2527) 3.1 (1.6-5.8) 0.03 (0.02-0.06)
2017 149 75 (60-110) 17 (12-30) 1604 (789-2713) 3.5 (1.8-5.7) 0.04 (0.02-0.06)
2018 196 60 (45-80) 12 (9-17) 798 (445-1284) 1.8 (1.0-3.1) 0.02 (0.01-0.03)
2019 194 50 (40-65) 9 (6-12) 596 (335-1079) 1.4 (0.8-2.4) 0.01 (0.008-0.02)

p-value <0.001 <0.001 <0.001 <0.001 <0.001

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The main findings of our study are:
a. There was a significant increase in the 

number of catheter ablation procedures 
performed in our laboratory over the study 
period.

b. The procedure time and the radiation 
indices (fluoroscopy time, DAP, ED, and LAR) 
significantly decreased over the study period 
(p<0.001 for all the parameters).

c. The trend of a significant decrease in pro-
cedure time and radiation exposure continued 
when the data were divided into two groups 
based on the fluoroscopy frame rate (p<0.001 
for all the parameters).

The radiation indices reported in different 
studies of catheter ablation procedures are pre-
sented in Table 4. The radiation indices re ported 
are comparable to that of the published data.

Injury caused by exposure to ionizing ra-
diation can be classified into two groups: a) the 
deterministic effects and b) the stochastic 
effects. Deterministic effects are dose-de pen-
dent (e.g., cataracts and skin injuries). A 
threshold radiation dose is a radiation dose 

below which the deterministic effects are not 
produced.

On the other hand, even a tiny radiation 
dose involves an increased risk of stochastic 
effects (e.g., cancer), and the chances of 
suffering that effect are directly proportional 
to the radiation dose.

As no radiation dose is safe, the policy of 
maintaining radiation exposure level is depen-
dent on the “as low as reasonably achievable” 
(ALARA) principle. [4]

Some of the factors that influence the 
extent of ionizing radiation exposure in a 
cardiac EP laboratory are: 

1) Operator dependent: a) experience of 
the operators, b) training of operators with 
simulators, c) radiation awareness of the staff, 
d) C-arm projection used during the procedure, 
e) fluoroscopy frame rate, f) cine duration, 
g) cine substitution by stored fluoroscopy, 
h) fluoroscopy use during catheter removal 
from the body, i) collimation of the X-ray 
system, j) pelvic radiation, k) written report of 
the patient’s radiation exposure during the 
procedure.

Table 3. Impact of fluoroscopy frame rate change on procedure time and radiation indices.  
Pre-group: procedures performed at 7.5 fps; post-group: procedures performed at 3.75 fps

Number Procedure time (mins)
Fluoroscopy 
time (mins)

DAP
(cGy/cm2)

ED
(mSv)

LAR,
%

Pre 260 75 (55-104) 18 (12-27) 1432 (780-2564) 3.2 (1.8-5.7) 0.03 (0.02-0.06)
Post 375 55 (40-75) 10 (7-15) 698 (392-1176) 1.6 (0.9-2.7) 0.02 (0.01-0.03)

p-value <0.001 <0.001 <0.001 <0.001 <0.001

Table 4. Reported radiation exposure in catheter ablation of supraventricular tachycardias (SVT). 
Adapted from [9]

Study Type of study Number of patients
Fluoroscopy 
time (mins) DAP (cGy/cm

2) Effective Dose (mSv)
Smith IR et al. 
[10]

Retrospective AVNRT 270
AVRT 135

2.1 (1.3-4.5)
23.8 (13.4-45.3)

260 (170-610)
2690 (1600-5410)

–

Rogers DP  
et al. [7]

Observational Pre DRM 147 
(AVNRT/AVRT)
Post DRM 257
(AVNRT/AVRT)

– 2040±2690

800±1030

3.3

1.24

Heidbuchel H 
et al. [4]

EHRA practical 
guide

– – – 4.4 (1.6-25)

Casella M  
et al. [6]

Multicentre 
randomized

Pre DRM 128
Post DRM 134

14.32 (9.08-
22.43)

0 (0-0.2)

2036 (54–5297)
278 (80–791)

8.87 (3.67–22.01)
0 (0–0.08)

See J et al. 
[11]

Observational Pre DRM AVRT 55
Post DRM AVRT 44

49.0 ± 36.3
14.1 ± 13.4

3292 ± 3282.7
654.4 ± 645.5

–

Casella M  
et al. [9]

Retrospective 979 (SVT) 13(6-21) 1721(727-3884) 4.1(1.8-9.1)

Our data Retrospective Pre 260
Post 375

18 (12-27)
10 (7-15)

1432 (780-2564)
698 (392-1176)

3.2 (1.8-5.7)
1.6 (0.9-2.7)

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2) Patient dependent: a) body habitus of the 
patient, b) arrhythmic lesion to be ablated.

3) Technology dependent: a) X-ray system, 
b) combination with computed tomography 
(CT), c) three-dimensional electroanatomic 
mapping systems, d) shielding of the laboratory 
personnel. [4]

The factors that lead to decreased radiation 
exposure in the cardiac EP laboratory are:

1) Operator dependent: a) expert operators, 
b) operators who have been trained with 
simulators, c) radiation aware staff, d) predo-
minant usage of right anterior oblique C-arm 
projection than an anteroposterior of left 
anterior oblique projection, e) low frame rate 
of fluoroscopy (<6 fps), f) short cine duration, 
g) frequent cine substitution by stored fluo-
roscopy, h) catheter withdrawal from the body 
without using fluoroscopy, i) optimized and 
adapted collimation, j) avoidance of pelvic 
radiation, k) a written report of the patient’s 
radiation exposure that includes air kerma or 
dose area product received during the pro-
cedure.

2) Patient dependent: lean body habitus of 
the patients, supraventricular tachycardia 
ablation than atrial fibrillation ablation or 
ventricular tachycardia ablation, 

3) Technology dependent: cardiac EP tuned 
X-ray system which has been adequately 
maintained and inspected for quality control, 
no preprocedural or rotational computed 
tomography, the predominant use of three-
dimensional electroanatomic mapping systems, 
proper shielding which includes above and 
below the table or cabin shielding [4].

One of the most efficient ways to decrease 
radiation exposure during the ablation of 
accessory pathways is to perform these 
procedures with the help of three-dimensional 
electroanatomic mapping, which has been 
shown to decrease radiation exposure in such 
procedures significantly.

No-Party trial was the first multicentre, 
prospective, randomized trial that compared 
conventional fluoroscopy-guided catheter 
ablation procedures with procedures performed 
using the three-dimensional electroanatomic 
mapping system in the patients undergoing EP 
study for supraventricular tachycardias, 36% of 
whom were AP ablation procedures [6]. In this 
trial, three-dimensional electroanatomic 
mapping significantly reduced fluoroscopy time 
and ED (0 seconds and 0 mSv) when compared 
to the procedures performed under fluoroscopic 
guidance (859 seconds and 8.87 mSv) (p<0.00001).

But the use of three-dimensional electro-
anatomic mapping systems is restricted due to 
various logistic reasons (availability, lack of 
expertise); we need to find alternative ways to 
decrease radiation exposure during catheter 
ablation procedures [4].

Rogers A J et al. conducted a study to 
evaluate the effect of radiation dose-reduction 
maneuver on the radiation exposure in EP 
laboratory. Atrioventricular nodal reentrant and 
AP-mediated tachycardia was 64% of catheter 
ablation procedures. They showed that with the 
simple maneuver of removing a secondary 
radiation grid to improve image quality and 
reducing the fluoroscopy pulse rate from 12.5 
to 6.25 pulses/second, a radiation dose reduced 
from 20.4 to 8.0 Gycm2. Additionally, the risk of 
radiation-related fatal malignancy was reduced 
by 63 due to the implementation of the 
maneuver. This study showed the importance 
of selecting electrophysiology laboratory 
parameters in reducing radiation exposure 
during catheter ablation procedures [7].

Voskoboinik A et al. conducted a prospective 
study to analyze the trends in radiation 
exposure during AF ablation at a single center 
over 12 years. A significant and progressive 
decrease in the fluoroscopy time and ED was 
observed over time. The significant decrease in 
the patient and operator radiation exposure 
was attributed to increased operator experience, 
higher annual case volume, technology 
evolution over time, and recent use of contact 
force-sensing catheters. [8]

More recently, Casella M et al. have reported 
fluoroscopy data from their retrospective 
analysis of various EP and device implantation 
procedures at a large volume laboratory over 
7 years. Fluoroscopy time, DAP, and ED showed 
a statistically significant reduction trend for all 
EP procedures. Based on the obtained results, 
it was proposed that a combination of operator 
awareness about the fluoroscopy-associated 
risk and technological advancement can be 
used for optimizing the use of fluoroscopy in 
EP procedures [9].

One of the significant limitations of this 
study, other than being a retrospective 
analysis, is that one can argue that a significant 
decrease in the procedure duration can solely 
explain the changes in the radiation exposure 
in the procedure time, which is also reflected 
in the decrease in the fluoroscopy time. If there 
is a significant decrease in the procedure time, 
the radiation exposure will automatically 
decrease.

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Some of the other limitations of this study 
are that data regarding some of the other 
factors that influence radiation exposure during 
procedures (e.g., body mass index of the 
patients, cine exposure duration during the 
procedures) performed under fluoroscopy was 
not available. This study is based on retrospective 
data collected from a single center, and the 
results cannot be generalized to other centers. 
As already alluded to, radiation exposure also 
depends on the individual expertise of 
operators, but data regarding the radiation 
exposure of individual operators was not 
available. 

We propose that in our study, the decrease 
in the radiation indices is not solely because of 
the reduction in fluoroscopy frame rate but 
because of other factors, too, one being a more 
than 200% increase in the yearly number of 
ablation procedures performed over the study 
period. Any modern electrophysiology labo-
ratory will face the same scenario. 

Conclusions
A reduction in the fluoroscopy frame rate 

and improvement in the electrophysiology 
laboratory workflow leads to a significant 
decrease in the radiation exposure during 
catheter ablation procedures of accessory 
pathway-mediated tachycardias.

Conflict of interest
The authors declare no conflict of interest.
Authors’ contributions
Muzaffar Ali: formal analysis, writing – 

original draft, investigation, formal analysis. 
Bharatraj Banavalikar: writing – reviewing and 
editing, investigation, formal analysis. Milan 
Kumar Ghadei: formal analysis, writing – original 
draft, investigation, formal analysis. Anju 
Kottayan: formal analysis, writing – original 
draft, investigation, formal analysis. Deepak 
Padmanabhan: writing – reviewing and editing, 
investigation, formal analysis. Jayaprakash 
Shenthar: conceptualization, methodology, 
writing – reviewing and editing

ІОНІЗУюЧЕ ОПРОМІНЕННЯ ПРИ РАДІОЧАСТОТНІй АБЛЯЦІЇ ДОДАТКОВИХ 
шЛЯХІВ ПРОВЕДЕННЯ У ЕЛЕКТРОфІЗІОЛОГІЇ СЕРЦЯ: РЕТРОСПЕКТИВНИй 
АНАЛІЗ

*M. Ali1,2, B. Banavalikar1, M.K. Ghadei1, A. Kottayan1, D. Padmanabhan1, J. Shenthar1
1 – DEPARTMENT OF CARDIAC ELECTROPHYSIOLOGY, SRI JAYADEVA INSTITUTE OF CARDIOVASCULAR SCIENCES 

AND RESEARCH, BANGALORE, INDIA
2 – DEPARTMENT OF CARDIOLOGY, SHER-I-KASHMIR INSTITUTE OF MEDICAL SCIENCES, SRINAGAR,  

KASHMIR, INDIA

Вступ. Радіочастотна катетерна абляція (КА) метод вибору лікування у пацієнтів з тахікардією, 
додатковими шляхами (ДШ). Більшість таких процедур проводиться під флюо роскопічним наглядом, 
що призводить до значного опромінення пацієнта та персоналу лабораторії. У цьому аналізі ми 
розглянули радіаційне опромінення в процедурах КАДШ, виконаних без підтримки тривимірної системи 
електроанатомічного відображення. Ми проаналізували зміни показників експозиції за період 
дослідження та вплив зміни частоти кадрів флюороскопії (FFR).

Мета. Метою цього дослідження є (1) кількісна оцінка радіаційного опромінення в процедурах абляції 
додаткових шляхів, (2) аналіз тенденції радіаційного опромінення з часом та (3) оцінка впливу зменшення 
частоти кадрів флюороскопії на показники радіаційного опромінення під час цієї процедури.

Методи. Ми ретроспективно проаналізували всі процедури абляції ДШ, проведені в нашому 
інституті з січня 2016 року по грудень 2019 року. Зібрані дані: вік, стать, місце розташування ДШ на 
основі успішного місця абляції на флюороскопії, час процедури, час флюороскопії та індекс доза опро-
мінення відносно площі (DAP). Ефективну дозу (ЕД) оцінювали за DAP. Дані процедур, проведених до січня 
2018 р. (група “До”), порівнювались із даними процедур, проведених після цієї дати (група “Після”). 
Процедури групи “До” виконувались із частотою FFR 7,5 кадрів в секунду (fps), а процедури групи “Після” – 
з частотою FFR 3,75 fps.

Результати. Загальна кількість процедур, включених до аналізу, становила 635. Середній вік 
пацієнтів становив 39±14 років, і 401 з них (63%) були чоловіками. Найчастіше зустрічалися ліво-
латеральні ДШ (38%). Показники тривалості процедури та опромінення зменшилися протягом періоду 
дослідження (р<0,001). Процедури групи “Після” мали значно коротший час проведення КА та менший 
радіаційний вплив, ніж процедури групи “До”.

Висновки. Зменшення FFR було пов'язане зі значним зменшенням радіаційного опромінення в 
процедурах абляції ДШ.

КЛЮЧОВІ СЛОВА: додаткові шляхи проведення; катетерна абляція; дозування опромінення; 
час флюороскопії; радіаційне опромінення.

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ISSN 2413-6077. IJmmR 2021 Vol. 7 Issue 1

Information about the authors
Muzaffar Ali MD, DM: Department of Cardiac Electrophysiology, Sri Jayadeva Institute of Cardiovascular 

Sciences and Research, Bangalore, India. 
ORCID 0000-0002-3489-5864, email: dralmuzaffar@gmail.com
Bharatraj Banavalikar MD, DM: Department of Cardiac Electrophysiology, Sri Jayadeva Institute of 

Cardiovascular Sciences and Research, Bangalore, India. 
ORCID 0000-0003-1116-3967, email: bharatrajnb@gmail.com
Milan Kumar Ghadei MD, DM: Department of Cardiac Electrophysiology, Sri Jayadeva Institute of 

Cardiovascular Sciences and Research, Bangalore, India. dr.milan80@gmail.com
Anju Kottayan BSc: Department of Cardiac Electrophysiology, Sri Jayadeva Institute of Cardiovascular 

Sciences and Research, Bangalore, India. anjukottayan@gmail.com
Deepak Padmanabhan MD, DM: Department of Cardiac Electrophysiology, Sri Jayadeva Institute of 

Cardiovascular Sciences and Research, Bangalore, India. 
ORCID 0000-0002-9127-9275, email: deepak.padmanabhan@gmail.com
Jayaprakash Shenthar MD, DM, FACC, FRCP (Lond): Department of Cardiac Electrophysiology, Sri 

Jayadeva Institute of Cardiovascular Sciences and Research, Bangalore, India. 
ORCID 0000-0003-4509-7515, email: jpsbhat@gmail.com

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Received 23 May 2021; revised 20 Jun 2021; 
accepted 22 Jun 2021.

This is open access article distributed under the Creative Com-
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distribution, and reproduction in any medium, provided the 
original work is properly cited.

M. Ali et al.