Patients’ demographics characteristics are summarized in Table 1. Patients were elderly (mean age 76 ± 8 years) and the majority (60%) were men who had paroxysmal AF (52%). The most frequent comorbidities were hypertension (84%), hyperlipidemia (68%), and smoking (70%). All patients had a CHAD2DS2-VASc score ≥ 2 (mean 4.4 ± 1.5) and the HAS-BLED score ranged between 1–5 (mean 2.7 ± 0.9). Most patients (60%) were receiving non–vitamin K antagonist oral anticoagulants as antithrombotic therapy.
Table 1. Baseline characteristics (N=50)
Variable
|
Value
|
Age (years)
|
76±8
|
Male, n (%)
|
30 (60)
|
Body mass index (kg/m2)
|
29.2±4.4
|
Body surface area (m2)
|
1.99±0.26
|
Heart rate (bpm)
|
73±14
|
Systolic Blood Pressure (mmHg)
|
132±33
|
Diastolic Blood Pressure (mmHg)
|
73±14
|
Smoking, n (%)
|
35 (70)
|
Diabetes, n (%)
|
19 (38)
|
Hypertension, n (%)
|
42 (84)
|
Hyperlipidemia, n (%)
|
34 (68)
|
Chronic obstructive pulmonary disease, n (%)
|
7 (14)
|
Chronic kidney disease, n (%)
|
13 (26)
|
History of stroke or transit ischemic attack, n (%)
|
17 (34)
|
Type of Atrial fibrillation
Paroxysmal, n (%)
Persistent, n (%)
Long-standing persistent, n (%)
Permanent, n (%)
|
26 (52)
9 (18)
5 (10)
10 (20)
|
CHA2DS2-Vasc Score
2
3
4
5
6
7
|
5 (10)
11 (22)
11 (22)
9 (18)
9 (18)
5 (10)
|
Antithrombotic therapy
NOAC, n (%)
Warfarin, n (%)
Aspirin, n (%)
|
30 (60)
4 (8)
16 (32)
|
Data are presented as mean ± standard deviation, or n (percentage). NOAC: non–vitamin K antagonist oral anticoagulants.
|
The distribution of implanted device sizes was as follows: 21 mm device in 5 patients (10%), 24 mm device in 16 patients (32%), 27 mm device in 13 patients (26%), 30 mm device in 7 patients (14%) and 33 mm device in 9 patients (18%).
Three-dimensional measurements of the LAA orifice were feasible in 50 of 52 (96%) patients. As shown in Fig. 2, there was a significant increase of all dimensions of the LAA orifice following LAA occlusion with the Watchman device: diameter 1 (pre-device 18.1 ± 3.2 vs. post-device 21.5 ± 3.4 mm, p < 0.001), diameter 2 (20.6 ± 3.9 vs. 22.1 ± 3.6 mm, p < 0.001), minimum diameter (17.6 ± 3.1 vs. 21.3 ± 3.4 mm, p < 0.001), maximum diameter (21.5 ± 3.9 vs. 22.4 ± 3.6 mm, p = 0.022), circumference (63.6 ± 10.7 vs. 69.6 ± 10.5 mm, p < 0.001), area (3.1 ± 1.1 vs. 3.9 ± 1.2 cm2, p < 0.001).
The percent increase was 18.8% for diameter 1, 7.3% for diameter 2, 21.0% for minimum diameter, 4.2% for maximum diameter, 9.4% for circumference and 25.8% for area. We compared the percent increase in area -the LAA orifice dimension that showed the greatest percentage increase after the Watchman implant- according to the AF type and the implanted device size. The percent increase in area was not statistically different in patients with paroxysmal AF than in those with other types of AF (22.8%, IQR: 12.4–52.5 vs. 17.5%, IQR: 4.6–31.3, p = 0.114); and it was similar in patients who received larger Watchman devices (27, 30 and 33 mm) than in those who received smaller devices (21 and 24 mm) (20.0%, IQR: 12.8–34.5 vs. 18.7%, IQR: 7.8–45.0, p = 0.989).
Eccentricity index decreased and showed a value closer to l after device placement (pre-device 1.23 ± 0.16 vs. post-device 1.06 ± 0.06, p < 0.001), which means that the LAA orifice changed from an ellipsoid geometry to a more circular shape.
As shown in Fig. 3, there was no significant difference in the LUPV peak S velocity pre and post LAA occlusion (0.29 ± 0.15 vs. 0.30 ± 0.14 cm/s, p = 0.637) nor in the peak LUPV peak D velocity (0.47 ± 0.19 vs. 0.48 ± 0.20 cm/s, p = 0.549).
Table 2 shows the results of the reliability analysis of 3D measurements of LAA orifice. Intra-observer reliability was good to excellent for diameter 1, and excellent for diameter 2, minimum diameter, maximum diameter, circumference, and area. Inter-observer reliability was good to excellent for all parameters. Table S1 in the Supplementary Material shows the reliability analysis separating the pre- and post-device measurements. Intra-observer agreement was better in the post-device measurements, mainly for diameter 1 and minimum diameter, while the inter-observer agreement was better in the pre-device measurements.
Table 2. Intra- and Inter-Observer Variabilities in 3D Measurements of LAA orifice
LAA orifice parameters
|
Intra-observer reliability
|
p value
|
Inter-observer reliability
|
p value
|
Diameter 1
|
0.97
[0.89-0.99]
|
<0.001
|
0.97
[0.87-0.99]
|
<0.001
|
Diameter 2
|
0.98
[0.91-0.99]
|
<0.001
|
0.97
[0.86-0.99]
|
<0.001
|
Minimum diameter
|
0.98
[0.90-0.99]
|
<0.001
|
0.97
[0.88-0.99]
|
<0.001
|
Maximum diameter
|
0.97
[0.90-0.99]
|
<0.001
|
0.95
[0.82-0.99]
|
<0.001
|
Circumference
|
0.98
[0.95-0.99]
|
<0.001
|
0.96
[0.83-0.99]
|
<0.001
|
Area
|
0.99
[0.97-0.99]
|
<0.001
|
0.97
[0.86-0.99]
|
<0.001
|
Data are presented as intraclass correlation coefficient [95% confidence intervals]. LAA: left atrial appendage.
|
Peri-device leak was noted in 11 (22 %) patients, all size ≤2 mm. The post-device eccentricity index tended to be higher, meaning a more circular LAA orifice, in patients with peri-device leak compared with those without leak although the difference was not statistically significant (1.07 ± 0.10 vs. 1.05 ± 0.05, respectively, p = 0.319).