Table 1.

Scoring system for LA SEC (11).

Grade	Definition
0	None (absence of echogenicity)
1+	Mild (minimal echogenicity located in the LA appendage or sparely distributed in the main cavity of the left atrium; may be detectable only transiently during the cardiac cycle; imperceptible at operating gain settings for two dimensional echocardiographic analysis)
2+	Mild to moderate (more dense swirling pattern than grade 1+ but with similar distribution; detectable without increased gain settings)
3+	Moderate (dense swirling pattern in the LAA, generally associated with somewhat lesser intensity in the main cavity; may fluctuate in intensity but detectable constantly throughout the cardiac cycle)
4+	Severe (intense echo density and very slow swirling patterns in the LAA, usually with similar density in the main cavity)