Clinical Implications of Left Atrial Appendage Flow Patterns in Nonrheumatic Atrial Fibrillation: Results

Clinical Implications of Left Atrial Appendage Flow Patterns in Nonrheumatic Atrial Fibrillation: ResultsPatient Сharacteristics
All the patients were divided into two groups based on the differences in LAA flow patterns. In patients in group 1 (n = 17), irregular but well-defined LAA emptying and filling Doppler flow signals could be recorded (Fig 2). Patients in group 2 (n = 12), there were very low flow signals and, sometimes, no blood flow signal could be detected in the LAA (Fig 3). The baseline variables of patients in these two groups are listed in Table 1. There were no significant differences in age, sex, mean duration of AF, left ventricular end-diastolic dimension, left ventricular ejection fraction, or current use of anticoagulant or antiplatelet agents between these two groups. However, the left atrial diameter was significantly larger in group 2 patients (42.8 ±4.2 mm vs 36.6 ± 8.8 mm; p < 0.05). canadian neightbor pharmacy

The LAA size and LAA function in these two groups of patients were compared in Table 2. No significant difference was found in LAA maximal area between these two groups (5.2 ±2.1 cm2 vs 5.0 ± 1.9 cm2; p = NS). However, patients in group 1 tended to have better LAA ejection fraction (42.6 ±14.1 vs 26.4 ±15.2; p < 0.05) and higher LAA peak emptying velocity (0.36 ±0.16 vs 0.13 ±0.03; p< 0.001).
LAA SEC and Thrombus Formation
The incidence of LAA SEC and thrombus formation in patients between these two groups was compared in Table 3. The LAA SEC was detected in 9 of 29 patients (31 percent) by TEE, and none of this could be detected by transthoracic echocardiography. All nine patients had LAA SEC occurring with left atrium SEC at the same time. Three of 29 patients (10.3 percent) had LAA thrombus, and no thrombus was found in the main left atrial cavity in all 29 patients. Three patients with LAA thrombus had LAA SEC. Thus, LAA thrombus existed in 3 of 9 patients (33.3 percent) with LAA SEC, but in none of 20 patients without LAA SEC (p < 0.001). The incidence of LAA SEC was significantly higher in group 2 patients (p < 0.001) who had poorer LAA function. However, there was no difference in LAA thrombus formation between these two groups.

Figure-2

Figure 2. Left: Transesophageal echocardiography showing the sample volume (arrowhead) in the left atrial appendage (LAA) cavity. Right: Irregular but well-defined LAA emptying and filling Doppler signals were recorded.

Figure-3

Figure 3. Left: Transesophageal echocardiography showing the sample volume (arrowhead) in the left atrial appendage (LAA) cavitv. Right: Very low flow signals were recorded and, sometimes, no signals at all (arrow) could be detected.

Table 1 — Baseline Variables Among Patients With Two Different LAA Flow Patterns

Group 1 (n = 17) Group 2 (n = 12) p Value
Age, yr 63.6 ±10.7 64.0 ± 9.9 NS
Men/women 13/4 9/3 NS
Mean AF duration, mo 33.7 30.8 NS
Current aspirin use 8/17 5/12 NS
Current warfarin use 0/17 1/12 NS
LVEDD, mm 49.2 ± 6.9 48.1 ±5.7 NS
LVEF, % 65.9 ± 10.7 66.4 ± 10.8 NS
LAD, mm 36.6 ±8.8 43.1 ±4.1 <0.05

Table 2 — LAA Size and LAA Functin Among Patients With Two Different LAA Flow Patterns

Croup 1 (n = 17) Group 2 (n = 12) p Value
LAA maximal area, cm2 5.2 ±2.1 5.0 ±1.9 NS
LAA EF, % 42.6 ±14.1 26.4 ± 15.2 <0.05
LAA peak emptying velocity, m/s 0.36 ±0.16 0.13 ±0.03 <0.001

Table 3 — LAA SEC and Thrombus Formation Among Patients With Two Different LAA Flow Patterns

Group 1 (n = 17) Group 2 (n = 12) p Value
LAA SEC 1/17 8/12 <0.001
LAA thrombus 1/17 2/12 NS*
This entry was posted in Nonrheumatic Atrial Fibrillation and tagged echocardiography, ejection fraction, thromboembolism, thrombus.