Cardiac function in relation to rhythm outcome after intraoperative epicardial left atrial cryoablation

Figures & data

Figure 1. M-mode registration of mitral annulus motion. Atrial contraction (A) is marked. During atrial systole, the left atrial maximal longitudinal axis excursion was measured as the maximum mitral motion during the left atrial contraction.

Table I. Patient characteristics.

	Cryoablation + CABG (n = 35)	CABG alone (n = 35)	p^#
Age; years	71.7 ± 5.3 (54–81)	70.1 ± 6.8 (53–84)	0.36
Sex; male/female (n)	32/3	32/3	1.00
Body mass index	27.2 ± 3.3 (22.7–36.5)	28.3 ± 3.2 (20.7–38.0)	0.04
Sinus/AF (n)	17/18	11/24	0.22
Type of AF
Paroxysmal/persistent	20 (57)	21 (60)	1.00
AF history; months (0/1)*	114 ± 112 (11–353)	59 ± 76 (4–264)	0.04
Permanent	15 (43)	14 (40)	1.00
AF history; months (0/3)	103 ± 53 (17–208)	139 ± 91 (16–299)	0.36
Other comorbitidy
Hypertension	21 (60)	23 (66)	0.80
Diabetes mellitus	10 (29)	11 (31)	1.00
History of embolic stroke/TIA	8 (23)	1 (3)	0.03
Myocardial infarction	24 (69)	16 (46)	0.09
Hyperlipidemia	26 (74)	26 (74)	1.00
Chronic obstructive pulmonary disease	2 (6)	1 (3)	1.00
Heart failure	4 (11)	3 (9)	1.00
PCI-procedures	4 (11)	7 (20)	0.51
Symptomatology
NYHA functional class (2/0)			0.50**
I	13 (39)	18 (51)
II	14 (42)	10 (29)
IIIA	4 (12)	5 (14)
IIIB	2 (6)	2 (6)
LVEF; % (4/3)	54.1 ± 11.0 (25–70)	52.8 ± 7.8 (38–70)	0.28
Left atrial area; cm² (4/3)	25.4 ± 5.8 (17–38)	28.0 ± 6.4 (18–48)	0.10
Right atrial area; cm² (4/3)	20.5 ± 5.5 (11–37)	23.1 ± 5.9 (14–45)	0.08
Medication
Betablocker	25 (71)	29 (83)	0.39
Calcium channel blocker	0 (0)	2 (6)	0.49
Digoxin	9 (26)	6 (17)	0.56
Sotalol	5 (14)	1 (3)	0.20
Amiodarone	2 (6)	0 (0)	0.49
ACE-inhibitors/ARB	16 (46)	20 (57)	0.47
Lipid lowering drugs	21 (60)	23 (66)	0.80
Diuretics	12 (34)	15 (43)	0.62
Warfarin/LMWH	20 (57)	19 (54)	1.00
Aspirin/Clopidogrel	24 (69)	20 (57)	0.46

ACE, angiotensin converting enzyme; AF, atrial fibrillation; ARB, angiotensin receptor blocker; CABG, coronary artery bypass grafting; DC, direct current; LMWH, low molecular weight heparin; LVEF, left ventricular ejection fraction; NYHA, New York Heart Association; PCI, percutaneous coronary intervention; TIA, transient ischemic attack.

All results are presented as n (%) or mean ± sd (min-max), unless otherwise stated, n = number.

^#For difference between treatment groups.

*Number of patients with missing information in the two treatment groups, respectively.

**Ordered degree of functional class used in p-values calculation.

Figure 2. Kaplan-Meier curve showing the freedom from documented atrial fibrillation after the three month therapy stabilization period.

Table II. Patients before surgery and at follow-up 22 ± 6 months postoperatively (all echocardiographic data included in the results, only patients with echo at corresponding time points included).

	Patients before surgery			Patients at follow-up
	Cryo	Controls	p	Cryo	Controls	p
Males/Females; n	30/3	29/3	1.00	25/3	28/3	1.00
Age (years)	72 ± 5	70 ± 7	0.38	71 ± 5	70 ± 7	0.57
AF paroxysmal/permanent/persistent^#; n	18/15/0	15/13/4	0.14	16/12/0	16/11/4	0.19
AF duration# (years) (0/4/0/3)*	10 ± 8	8 ± 8	0.12	9 ± 8	7 ± 8	0.13
median (min-max)	6 (1–29)	3 (< 1–25)		6 (1–29)	3 (< 1–25)
Sinus/AF or AFL	15/18	11/21	0.45	18/10	11/20	0.04
Heart rate (bpm) (1/0/0/1)*	70 ± 13	71 ± 15	0.81	71 ± 16	67 ± 15	0.33
LV diameter (mm) (6/3/0/1)*	48 ± 5	51 ± 6	0.06	50 ± 6	51 ± 7	0.48
LVEF (%) (2/0/3/1)*	54 ± 11	53 ± 8	0.28	50 ± 10	46 ± 11	0.12
Left atrial area (cm²) (2/0/0/0)*	25 ± 6	28 ± 6	0.10	29 ± 7	30 ± 6	0.35
Right atrial area (cm²) (2/0/2/1)*	21 ± 5	23 ± 6	0.08	24 ± 6	26 ± 6	0.04

All results are presented as mean ± S.D., unless otherwise stated, n, number; bpm, beats per minute.

*Number of patients where information was missing in the four groups, respectively.

#at baseline.

Table III. Patients with sinus rhythm both before surgery and at follow-up 22 ± 6 months postoperatively (only patients with echo both before surgery and at follow-up included).

	Cryo patients (n = 12)			Control patients (n = 9)
	Before surgery	At follow-up	p^#	Before surgery	At follow-up	p^#	p^##
Age (years)	72 ± 6			70 ± 8
AF paroxysmal/permanent/persistent; n	12/0/0			9/0/0
AF duration (years)	9 ± 8			7 ± 9
median (min-max)	6 (1–24)			3 (< 1–22)
Heart rate (bpm) (1/0)*	60 ± 8	63 ± 10	0.43	65 ± 13	59 ± 9	0.07	0.04
LV diameter (mm) (1/1)*	45 ± 5	49 ± 5	0.03	51 ± 7	50 ± 5	0.78	0.04
LVEF (%) (2/0)*		59 ± 6	56 ± 8	0.03	55 ± 9	53 ± 8	0.50
0.61
Left atrial area (cm²)	21 ± 4	26 ± 5	0.002	24 ± 4	26 ± 5	0.06	0.28
Right atrial area (cm²)	18 ± 4	21 ± 4	0.01	19 ± 3	23 ± 4	0.02	0.99
Mitral flow velocity during atrial systole (m/s) (1/0)*	0.76 ± 0.14	0.51 ± 0.20	0.002	0.70 ± 0.21	0.64 ± 0.26	0.27	0.009
Mitral annular excursion during atrial contraction (cm) (2/0)*	0.60 ± 0.18	0.46 ± 0.15	0.01	0.50 ± 0.14	0.49 ± 0.18	0.65	0.11

All results are presented as mean ± S.D., unless otherwise stated, n, number; bpm, beats per minute.

*Number of patients where information was missing in the cryo and control groups, respectively.

^#For change within group; ^## for difference in change between cryo and control groups.

Table IV. Patients with atrial fibrillation/flutter both before surgery and at follow-up 22 ± 6 months postoperatively (only patients with echo both before surgery and at follow-up included).

	Cryo patients (n = 9)			Control patients (n = 17)
	Before surgery	At follow-up	p^#	Before surgery	At follow-up	p^#	p^##
Age (years)	70 ± 7			70 ± 6
AF paroxysmal/permanent/persistent; n	0/9/0			3/11/3
AF duration (years) (0/3)*	8 ± 5			9 ± 8
median (min-max)	8 (1–17)			6 (< 1–25)
Heart rate (bpm)	76 ± 8	83 ± 18	0.34	72 ± 13	74 ± 16	0.81	0.45
LV diameter (mm) (1/2)*	51 ± 4	49 ± 6	0.19	51 ± 6	51 ± 6	0.81	0.28
LVEF (%)	47 ± 15	45 ± 11	0.47	53 ± 8	44 ± 9	0.002	0.21
Left atrial area (cm²) (1/0)*	30 ± 7	33 ± 8	0.047	30 ± 7	33 ± 5	0.03	0.94
Right atrial area (cm²) (2/0)*	24 ± 4	28 ± 7	0.09	26 ± 6	29 ± 6	0.0006	0.96

All results are presented as mean ± S.D., unless otherwise stated, n, number; bpm, beats per minute.

*number of patients where information was missing in the cryo and control groups, respectively.

^# for change within group; ^## for difference in change between cryo and control groups.