17-Segment Model — LV Segmental Analysis & Coronary Territory Map

Echo Reference — Chamber Quantification

LV Segmental Analysis

Interactive 17-segment bull's-eye plot with coronary artery territory mapping. Click any segment to see its name, number, coronary supply, and which echo views best visualise it.

Interactive Diagram

17-Segment Bull's-Eye

Click or tap any segment to view details. Segments are colour-coded by primary coronary artery territory.

LAD

LCx

RCA

Variable (LAD or LCx or RCA)

Click or tap any segment on the bull's-eye to see its name, number, coronary territory, and the echo views that best visualise it.

Level

Coronary territory

Best views

Wall

Segments by Apical View

Each standard apical view visualises 6 wall segments (basal, mid, and apical levels of two opposing walls) plus the apex.

Apical 4-Chamber

1 — Basal lateral (5)

2 — Mid lateral (11)

3 — Apical lateral (16)

4 — Apical septal (14)

5 — Mid inferoseptal (9)¹

6 — Basal inferoseptal (3)¹

+ Apex (17)

Apical 2-Chamber

1 — Basal anterior (1)

2 — Mid anterior (7)

3 — Apical anterior (13)

4 — Apical inferior (15)

5 — Mid inferior (10)

6 — Basal inferior (4)

+ Apex (17)

Apical 3-Chamber (LAX)

1 — Basal anterolateral (6)²

2 — Mid anterolateral (12)²

3 — Apical lateral (16)²

4 — Apical septal (14)²

5 — Mid anteroseptal (8)

6 — Basal anteroseptal (2)

+ Apex (17)

¹ A4C septum: The septum in the apical 4-chamber view corresponds to the inferoseptum (segments 3, 9, 14), not the anteroseptum. The anteroseptum (segments 2, 8) is seen in the apical 3-chamber / long-axis view.

² A3C lateral wall: The lateral wall in the apical 3-chamber view corresponds to the anterolateral wall (segments 6, 12), while the apical segments (14, 16) overlap with the 4-chamber view.

Coronary Artery Territory Mapping

Primary coronary supply for each segment. Note that there is significant inter-individual variability, particularly at the junctions between territories (inferior, inferolateral, and apical segments). The apex (segment 17) is most commonly supplied by the LAD but can be supplied by any of the three vessels.

#	Segment	Level	Primary Artery
1	Basal anterior	Basal	LAD
2	Basal anteroseptal	Basal	LAD
3	Basal inferoseptal	Basal	RCA
4	Basal inferior	Basal	RCA
5	Basal inferolateral	Basal	LCx
6	Basal anterolateral	Basal	LCx
7	Mid anterior	Mid	LAD
8	Mid anteroseptal	Mid	LAD
9	Mid inferoseptal	Mid	RCA
10	Mid inferior	Mid	RCA
11	Mid inferolateral	Mid	LCx
12	Mid anterolateral	Mid	LCx
13	Apical anterior	Apical	LAD
14	Apical septal	Apical	LAD
15	Apical inferior	Apical	RCA
16	Apical lateral	Apical	LCx
17	Apex	Apex	Variable (usually LAD)

Coronary dominance: Standard coronary territory maps assume right-dominant circulation (~80–85% of individuals). In left-dominant or co-dominant systems, the inferior and inferolateral segments may be supplied by the circumflex rather than the RCA. Territory assignment should therefore be interpreted with clinical and angiographic context.

Wall Motion Score

Each segment is graded on a standardised scale. The wall motion score index (WMSI) is calculated as the sum of individual segment scores divided by the number of segments visualised. A normal WMSI is 1.0.

Score	Wall Motion	Description
1	Normal or hyperkinetic	Normal endocardial inward motion and systolic wall thickening
2	Hypokinetic	Reduced endocardial inward motion and wall thickening
3	Akinetic	Absent endocardial inward motion and wall thickening
4	Dyskinetic	Outward systolic motion (paradoxical bulging)
5	Aneurysmal	Diastolic deformation with systolic dyskinesis

Stress echo interpretation: During stress echocardiography, new or worsening regional wall motion abnormalities indicate inducible ischaemia. The distribution of affected segments suggests the likely coronary territory, while the number of involved segments correlates with ischaemic burden and risk. Interpretation should consider coronary dominance, prior infarction, and the possibility of multivessel disease.

WMSI and prognosis: An elevated wall motion score index is associated with worse prognosis following myocardial infarction, with values above ~1.5–1.7 indicating significantly increased risk. Serial changes in WMSI are useful for tracking recovery or deterioration in ventricular function.

References

Lang RM, et al. Recommendations for Cardiac Chamber Quantification by Echocardiography in Adults: An Update from the American Society of Echocardiography and the European Association of Cardiovascular Imaging. J Am Soc Echocardiogr. 2015;28:1–39.
Cerqueira MD, et al. Standardized Myocardial Segmentation and Nomenclature for Tomographic Imaging of the Heart: A Statement for Healthcare Professionals from the Cardiac Imaging Committee of the Council on Clinical Cardiology of the American Heart Association. Circulation. 2002;105:539–542.
Mitchell C, et al. Guidelines for Performing a Comprehensive Transthoracic Echocardiographic Examination in Adults: Recommendations from the American Society of Echocardiography. J Am Soc Echocardiogr. 2019;32(1):1–64.

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