Read a stress echo segment by segment and stage by stage. Each of the 17 segments is graded at rest, low dose, peak and recovery, and its response is classified. The pattern across the segments gives the territory, the extent and the conclusion.
Segment responses
Response
Rest
Low dose
Peak
Meaning
Normal
Normal
Hyperkinetic
Hyperkinetic
No ischaemia in that segment
Ischaemic
Normal
Normal
Hypo- or akinetic (or fails to augment)
Inducible ischaemia
Biphasic
Abnormal
Improves
Worsens
Viable and ischaemic (hibernation)
Sustained improvement
Abnormal
Improves
Improves further
Viable, no inducible ischaemia
Fixed
Akinetic
Akinetic
Akinetic
Scar (non-viable), especially if thin and bright
A normal segment should become hyperkinetic: it thickens more and moves further inward with dobutamine, and the cavity becomes smaller. A segment that merely stays "normal" while the rest of the ventricle becomes hyperkinetic can be an early sign of ischaemia.
Simulated proximal LAD ischaemia: normal at rest and low dose, akinetic apical and anterior segments at peak, partial recovery afterwards.
Wall motion score index (WMSI)
The WMSI is the sum of the segment scores divided by the number of segments scored (1 = normal, 2 = hypokinetic, 3 = akinetic, 4 = dyskinetic, 5 = aneurysmal). A normal ventricle has a WMSI of 1.0. Report it at rest and at peak: a rise at peak reflects the extent and severity of ischaemia.
Territory and extent
Map the abnormal segments to the coronary territories: LAD (anterior, anteroseptal and most apical segments), RCA (inferior and inferoseptal) and LCx (inferolateral and anterolateral). Abnormalities in more than one territory suggest multivessel or left main disease.
High-risk features
Ischaemia at low dose or at a low heart rate.
Extensive ischaemia: many segments or more than one territory.
LV cavity dilatation at peak, or a fall in EF instead of the normal rise.
Hypotension during stress with wall motion abnormalities.
ST elevation in leads without Q waves.
False positives and false negatives
False positives: abnormal septal motion from LBBB, RV pacing or previous cardiac surgery (the septum moves abnormally but thickens); the basal inferior and inferoseptal segments; foreshortened apical views; a hypertensive response; poor endocardial definition.
False negatives: a submaximal heart rate (often from beta-blockers), slow acquisition of peak images, a small hyperdynamic cavity, single-vessel or circumflex disease, and lateral wall dropout.
Structuring the report
Protocol: drugs and doses, atropine, peak heart rate and % of the age-predicted maximum, blood pressure response, symptoms, ECG and arrhythmia, reason for stopping.
Rest: LV size and EF, resting wall motion abnormalities, WMSI.
Stress: the response of each territory at low dose, peak and recovery; peak EF and WMSI.
Conclusion: positive, negative or non-diagnostic for inducible ischaemia; territory and extent; viability if relevant; high-risk features.
