15.1 LV Systolic Function, Simpson EF, Regional Motion, and Output

Build EF from valid volumes

Left ventricular ejection fraction, or LVEF, is the fraction of end-diastolic volume ejected during systole. It is not synonymous with myocardial contractility, stroke volume, or cardiac output. Record heart rate, rhythm, blood pressure, loading interventions, and ventilation because each can change an EF without changing intrinsic myocardium. Acquire nonforeshortened apical four- and two-chamber views with comparable long-axis lengths and the true apex visible. A rounded, shortened apex underestimates both volumes and may distort EF. Reposition the transducer before tracing rather than extending a contour beyond visible anatomy.

For the biplane method of disks, identify end-diastole at mitral closure or the largest LV cavity and end-systole at aortic closure or the smallest cavity. Trace the compacted myocardium–cavity interface in each view and phase. Follow the compacted endocardial boundary without detouring around individual papillary muscles or trabeculations; the volume contour therefore includes those structures within the measured LV chamber. Close the contour at the mitral annular plane without including LA. The software divides both views into corresponding disks to calculate EDV and ESV. Then:

LVEF = (EDV − ESV) / EDV × 100

An EDV of 150 mL paired with an ESV of 60 mL yields 90 mL of stroke volume and a 60% ejection fraction. Index volumes to body surface area, but EF itself is a percentage. The conventional 2-D normal LVEF ranges are 52%–72% in men and 54%–74% in women; use current laboratory, sex-, and method-specific references. Three-dimensional EF is preferred when a complete, high-quality dataset is feasible because it avoids geometric assumptions. It can still fail from dropout, stitching, incomplete pyramids, low temporal resolution, or incorrect automated borders. Preserve whether EF was visual, biplane, 3-D, or contrast-derived for serial interpretation.

Grade regional motion in multiple views

Evaluate wall thickening and inward endocardial excursion, not motion alone. Divide the LV into the standard 17-segment model and confirm each segment in orthogonal apical and short-axis planes whenever possible. Normal or hyperkinetic tissue thickens and moves inward; hypokinesis means reduced thickening and excursion, akinesis means absent or nearly absent thickening, and dyskinesis means paradoxical systolic expansion. Aneurysmal tissue has persistent diastolic deformation as well as abnormal systolic behavior. Name the segment, grade, and view quality rather than reporting a vague regional abnormality.

Translation, tethering, foreshortening, reverberation, and dropout can simulate abnormal motion. Basal inferoseptal or basal inferior excursion may be reduced by fibrous attachments while thickening remains preserved. LBBB, RV pacing, postoperative motion, RV pressure loading, and cardiomyopathy create noncoronary patterns. Compare adjacent segments and views, track the same tissue from diastole to systole, and reduce depth and sector width without losing landmarks. Strain can support subtle dysfunction but depends on tracking, frame rate, vendor, load, and timing; it does not replace a technically sound visual assessment.

Global and regional measures answer different questions. A small infarct may produce a clear regional abnormality with preserved EF, while diffuse cardiomyopathy can reduce EF without a territorial pattern. Acute severe MR may show a normal or high EF because blood ejects into a low-impedance LA even when forward output is poor. A sudden afterload increase can lower EF without new necrosis. Report regional motion, volumes, EF, loading, valve lesions, and image limitations together; do not diagnose ischemia from one low EF.

Calculate forward stroke volume and output

Doppler forward stroke volume is LVOT cross-sectional area × LVOT VTI. Measure LVOT diameter inner-edge to inner-edge in a correctly aligned parasternal long-axis plane at the same level represented by the PW sample. Calculate area as π × (diameter / 2)². From an apical long-axis or five-chamber window, place PW just proximal to the aortic valve in laminar flow, align parallel, and trace the dense modal VTI edge. Because diameter is squared, a small diameter error produces a much larger stroke-volume error. Moving the sample into acceleration, tracing noise, or mixing beats also biases output.

Cardiac output = stroke volume × heart rate, and cardiac index = cardiac output / BSA. Convert mL to liters before reporting output. Simpson stroke volume, EDV minus ESV, represents total LV ejection; LVOT Doppler measures forward systemic ejection. They may disagree with significant MR or AR, intracardiac shunt, arrhythmia, or mismatched timing and borders. Cross-check values rather than averaging them. A low cardiac output can coexist with preserved EF when EDV and stroke volume are both small, while a dilated LV may eject a large volume despite a reduced percentage. A defensible systolic report explains how each number was obtained and whether physiology supports it.

Verify serial change and flow meaning

Before calling recovery or deterioration, confirm that image plane, border convention, rhythm sampling, analysis method, blood pressure, and loading state are comparable. Reanalyze prior source images when a small numerical change conflicts with chamber size, regional motion, or clinical physiology. LVOT systolic stroke volume is antegrade aortic ejection; with important AR it includes recirculating volume and should not be equated with net systemic output.

EF is load and geometry dependent

A precise Simpson percentage can still mislead when the apex is foreshortened, borders are incomplete, loading has changed, or severe regurgitation separates total from forward ejection. Interpret EF with volumes, regional motion, output, valves, rhythm, and blood pressure.