Could any of the echocardiographic measurements be artifacts due to suboptimal image quality despite the patient’s normal ejection fraction (55–60%) and normal diastolic function?

Could Measurements Be Artifacts Due to Limited Image Quality?

Yes, several measurements in this echocardiogram are likely artifactual or unreliable due to the acknowledged suboptimal image quality, despite the preserved ejection fraction and normal diastolic function. 1

Critical Discrepancies Suggesting Artifact

The most concerning finding is the severely reduced cardiac index of 1.53 L/min/m² and stroke volume index of 21 mL/m², which are profoundly abnormal and completely inconsistent with:

• Normal EF (55-60%)
• Normal diastolic function (E/e' = 8.8, e' velocities >10 cm/s)
• Normal chamber sizes
• Normal wall motion
• Normal valvular function

This internal inconsistency strongly indicates measurement artifact rather than true pathology. 1

Specific Measurements Most Vulnerable to Artifact

LVOT Measurements (Primary Source of Error)

The LVOT diameter of 1.7 cm is unusually small and likely represents the most significant measurement error. Even minor errors in LVOT diameter measurement are exponentially magnified because:

• Stroke volume calculation uses the formula: SV = π × (LVOT diameter/2)² × VTI
• A 2mm underestimation in LVOT diameter can reduce calculated stroke volume by ~20-25%
• Poor image quality makes accurate LVOT diameter measurement particularly challenging 2

The LVOT VTI of 18.4 cm is borderline low-normal, which combined with the small LVOT diameter, produces the spuriously low stroke volume and cardiac output.

Why These Measurements Are Artifact

In a patient with normal EF and diastolic function, the cardiac index should be ≥2.5 L/min/m² at rest. The reported value of 1.53 L/min/m² would indicate severe cardiogenic shock, which is clinically incompatible with:

• Normal chamber dimensions (LVIDd 3.8 cm, LVIDs 2.7 cm)
• Normal wall thickness
• Normal TAPSE (2.2 cm)
• Absence of significant valvular disease

Impact of Image Quality on Accuracy

European guidelines explicitly state that "when image quality is suboptimal/poor, the use of advanced echo techniques such as strain and 3D may become misleading" and that "a judgement of examination quality is important as the lack of some parameters can lead to inconclusive diagnosis." 1

Research demonstrates that:

• Image quality significantly affects measurement accuracy, with poor quality reducing agreement with cardiac MRI from ICC 0.81-0.87 (good quality) to 0.64-0.84 (poor quality) 3
• LVOT measurements are particularly susceptible to positioning errors and image plane artifacts 2
• Boundary tracing errors and geometric assumptions compound in patients with suboptimal windows 2

Clinical Interpretation

The preserved EF, normal diastolic parameters, and normal chamber dimensions represent the most reliable findings because:

• EF assessment is relatively robust even with suboptimal images when endocardial borders are visible
• Tissue Doppler velocities (e' = 13 cm/s) are less dependent on image quality
• Chamber dimensions can be measured if any adequate windows are obtained

The LVOT-derived hemodynamic calculations should be disregarded as they are internally inconsistent with the structural and functional findings.

Recommendations

Do not base clinical decisions on the cardiac output/cardiac index measurements in this study. Instead:

• Rely on the EF, diastolic function parameters, and chamber dimensions for clinical assessment
• If hemodynamic assessment is clinically necessary, consider:
  • Repeat echocardiography with contrast enhancement (improves accuracy and reproducibility) 4
  • Alternative imaging modality (cardiac MRI)
  • Direct hemodynamic assessment if critically important

The patient's cardiac function should be considered normal based on the reliable parameters (EF, diastolic function, chamber sizes), and the low cardiac output measurements should be attributed to technical artifact from suboptimal image quality affecting LVOT measurements. 1

{"question": "Could any of the echocardiographic measurements be artifacts due to suboptimal image quality despite the patient's normal ejection fraction (55–60%) and normal diastolic function?"}