Cardiol Res

Cardiology Research, ISSN 1923-2829 print, 1923-2837 online, Open Access

Article copyright, the authors; Journal compilation copyright, Cardiol Res and Elmer Press Inc

Journal website https://www.cardiologyres.org

Original Article

Volume 13, Number 2, April 2022, pages 97-103

Ablation Index Outcome in Redo Persistent Atrial Fibrillation Ablation: Results of a Short-Term Study

Figure 1. Kaplan-Meier analysis of AF recurrence at 12 months between the AI and CF groups, following redo PVI procedure, with adjusted 3-month blanking period. Y-axis demonstrates cumulative data for each group. Once AF was detected, the patient’s data were censored from follow-up. Blue line represents the AI interventional group. Red line represents the CF group. AF: atrial fibrillation; AI: ablation index; CF: contact force; PVI: pulmonary vein isolation.

Figure 2. Kaplan-Meier analysis of AF recurrence at 24 months between the AI and CF groups, following redo PVI procedure, with adjusted 3-month blanking period. Blue line represents the AI interventional group. Red line represents the CF group. AF: atrial fibrillation; AI: ablation index; CF: contact force; PVI: pulmonary vein isolation.

**Table 1.** Summary of Patient Demographics, Anti-Arrhythmic Drugs and Procedure Details
	Group 1: AI (n = 17)	Group 2: CF (n = 22)	P-value
*There was significantly higher rate of PVI ablation alone in group 2, the patients who underwent the CF procedure. The incidence of additional ablation lines was higher in the AF group. AI: ablation index; CF: contact force; PVI: pulmonary vein isolation; CKD: chronic kidney disease; LA: left atrium; LVEF: left ventricular ejection fraction.
Number, n	17	22	0.71
Female, n (%)	3 (18%)	6 (26%)	0.50
Age (yrs)	62 (57 - 67)	62 (57 - 67)	0.38
Weight (kg)	95 (87 - 103)	89.8 (81 - 98.5)	0.32
Height (m)	1.79 (1.74 - 1.8)	1.8 (1.76 - 1.84)	0.52
Comorbidities
Hypertension, n (%)	4 (24%)	7 (32%)	0.58
Obstructive sleep apnea, n (%)	0	2 (9%)	0.21
Obesity, n (%)	0	1 (5%)	0.39
Coronary artery disease, n (%)	2 (13%)	3 (14%)	0.88
Dyslipidemia, n (%)	0	3 (14%)	0.12
CKD, n (%)	1 (6%)	2 (9%)	0.72
LA volume (ml³)	29.5 (24.6 - 35.3)	36.6 (36.3 - 46.6)	0.12
LA diameter (cm)	4.6 (4.15 - 5.05)	4.38 (4.03 - 4.73)	0.66
LVEF (%)	58 (52.8 - 63.2)	61 (56.4 - 65.6)	0.85
CHADS₂VASC Score (n)	1.28 (1.1 - 1.4)	1.45 (1.3 - 1.6)	0.67
PV Reconnection, n (%)	17 (100%)	19 (86%)	0.10
Anti-arrhythmic
Bisoprolol, n (%)	6 (35%)	10 (45%)	0.54
Sotalol, n (%)	7 (41%)	8 (36%)	0.77
Metoprolol, n (%)	1 (6%)	2 (9%)	0.72
Drondarone, n (%)	1 (6%)	-	0.26
Flecainide, n (%)	3 (18%)	2 (9%)	0.41
Amiodarone, n (%)	1 (6%)	3 (14%)	0.44
Verapamil, n (%)	1 (6%)	-	0.26
Procedure details
Procedure time (min)	111.6 (98.8 - 124.4)	133 (116.3 - 149.7)	0.055
Fluoroscopy time (min)	12.5 (8.3 - 16.7)	11.5 (9.2 - 13.8)	0.49
Radiation dose (mGy)	51 (32.9 - 69.1)	48.7 (30.5 - 66.9)	0.14
Additional lines
PVI alone, n (%)	3 (18%)	8 (36%)	0.01*
PVI + 1 additional ablation line, n (%)	11 (65%)	12 (55%)	0.70
PVI + 2 additional ablation line, n (%)	3 (18%)	2 (9%)	0.74

Table 1. Summary of Patient Demographics, Anti-Arrhythmic Drugs and Procedure Details

Group 1: AI (n = 17)

Group 2: CF (n = 22)

P-value

*There was significantly higher rate of PVI ablation alone in group 2, the patients who underwent the CF procedure. The incidence of additional ablation lines was higher in the AF group. AI: ablation index; CF: contact force; PVI: pulmonary vein isolation; CKD: chronic kidney disease; LA: left atrium; LVEF: left ventricular ejection fraction.

Number, n

0.71

Female, n (%)

3 (18%)

6 (26%)

0.50

Age (yrs)

62 (57 - 67)

0.38

Weight (kg)

95 (87 - 103)

89.8 (81 - 98.5)

0.32

Height (m)

1.79 (1.74 - 1.8)

1.8 (1.76 - 1.84)

0.52

Comorbidities

Hypertension, n (%)

4 (24%)

7 (32%)

0.58

Obstructive sleep apnea, n (%)

2 (9%)

0.21

Obesity, n (%)

1 (5%)

0.39

Coronary artery disease, n (%)

2 (13%)

3 (14%)

0.88

Dyslipidemia, n (%)

3 (14%)

0.12

CKD, n (%)

1 (6%)

2 (9%)

0.72

LA volume (ml³)

29.5 (24.6 - 35.3)

36.6 (36.3 - 46.6)

0.12

LA diameter (cm)

4.6 (4.15 - 5.05)

4.38 (4.03 - 4.73)

0.66

LVEF (%)

58 (52.8 - 63.2)

61 (56.4 - 65.6)

0.85

CHADS₂VASC Score (n)

1.28 (1.1 - 1.4)

1.45 (1.3 - 1.6)

0.67

PV Reconnection, n (%)

17 (100%)

19 (86%)

0.10

Anti-arrhythmic

Bisoprolol, n (%)

6 (35%)

10 (45%)

0.54

Sotalol, n (%)

7 (41%)

8 (36%)

0.77

Metoprolol, n (%)

1 (6%)

2 (9%)

0.72

Drondarone, n (%)

1 (6%)

0.26

Flecainide, n (%)

3 (18%)

2 (9%)

0.41

Amiodarone, n (%)

1 (6%)

3 (14%)

0.44

Verapamil, n (%)

1 (6%)

0.26

Procedure details

Procedure time (min)

111.6 (98.8 - 124.4)

133 (116.3 - 149.7)

0.055

Fluoroscopy time (min)

12.5 (8.3 - 16.7)

11.5 (9.2 - 13.8)

0.49

Radiation dose (mGy)

51 (32.9 - 69.1)

48.7 (30.5 - 66.9)

0.14

Additional lines

PVI alone, n (%)

3 (18%)

8 (36%)

0.01*

PVI + 1 additional ablation line, n (%)

11 (65%)

12 (55%)

0.70

PVI + 2 additional ablation line, n (%)

3 (18%)

2 (9%)

0.74

**Table 2.** Summary of Follow-Up, Outcomes and Complications
	Group 1: AI (n = 17)	Group 2: CF (n = 22)	P-value
AI: ablation index; CF: contact force; AAD: anti-arrhythmic drug.
AAD change
Escalation, n (%)	2 (12%)	7 (32%)	0.15
De-escalation, n (%)	11 (65%)	6 (27%)	0.02
No change, n (%)	4 (14%)	9 (41%)	0.27
Complications
Intraprocedural complication	0	0	-
Post-procedure complications	0	0	-

Table 2. Summary of Follow-Up, Outcomes and Complications

Group 1: AI (n = 17)

Group 2: CF (n = 22)

P-value

AI: ablation index; CF: contact force; AAD: anti-arrhythmic drug.

AAD change

Escalation, n (%)

2 (12%)

7 (32%)

0.15

De-escalation, n (%)

11 (65%)

6 (27%)

0.02

No change, n (%)

4 (14%)

9 (41%)

0.27

Complications

Intraprocedural complication

Post-procedure complications