What is the initial diagnostic approach for a patient requiring a cardiac assessment using a 2D (two-dimensional) echocardiogram?

Initial Diagnostic Approach for 2D Echocardiography Cardiac Assessment

The initial diagnostic approach for a patient requiring cardiac assessment using a 2D echocardiogram should begin with a transthoracic echocardiography (TTE) performed with the highest-frequency transducer possible to enable high-resolution detailed evaluation of cardiac structures. 1

Standard Imaging Protocol

Essential Views and Imaging Planes

• Parasternal views: Short-axis at level of aortic valve, short-axis of left ventricle, long-axis of left ventricle
• Apical views: Four-chamber, two-chamber, and five-chamber views
• Subcostal views: For right heart assessment and in patients with poor acoustic windows
• Suprasternal notch views: For assessment of aorta and great vessels 1, 2

Specific Coronary Artery Assessment

When coronary artery evaluation is needed, focus on:

• Left main coronary artery (LMCA)
• Left anterior descending (LAD)
• Left circumflex
• Right coronary artery (proximal, middle, and distal segments)
• Posterior descending coronary artery 1

Key Parameters to Assess

Left Ventricular Function

• Ejection fraction (LVEF): Normal >50-55%, mildly reduced 45-50%, moderately reduced 30-45%, severely reduced <30%
• End-diastolic and end-systolic volumes: Indexed to body surface area
• Wall motion abnormalities: Regional assessment using 17-segment model
• Global longitudinal strain (GLS): For detection of subclinical dysfunction 2

Right Ventricular Function

• RV size and systolic function
• Tricuspid annular plane systolic excursion (TAPSE)
• RV fractional area change
• Estimated pulmonary artery systolic pressure 2

Valvular Assessment

• Aortic valve: Morphology, stenosis (valve area, mean/peak gradients), regurgitation
• Mitral valve: Morphology, stenosis (valve area, mean gradient), regurgitation
• Tricuspid valve: Morphology, regurgitation, annular diameter
• Pulmonic valve: Morphology, stenosis, regurgitation 1, 2

Diastolic Function

• Mitral inflow pattern (E/A ratio)
• Tissue Doppler velocities at mitral annulus (e')
• E/e' ratio (>15 suggests elevated left atrial pressure)
• Pulmonary vein flow velocities
• Left atrial size and volume 1, 2

Special Considerations

Sedation Requirements

• Sedation is frequently needed for children <3 years of age
• May also be required for older, irritable children
• If initial study quality is poor due to lack of sedation, a sedated study should be repeated within 48 hours 1

Technical Specifications

• Studies should be recorded in dynamic video or digital cine format
• Use the highest-frequency transducer possible, even for older children/adults
• Multiple imaging planes and transducer positions are required for optimal visualization 1

Follow-up Protocol

• For patients with valvular heart disease: Annual or semi-annual surveillance of LV function
• For patients with moderate to severe mitral regurgitation: Echocardiography every 6-12 months
• For patients with mild abnormalities: Yearly clinical evaluation with echocardiography only if clinical evidence of worsening 1

Common Pitfalls and Limitations

• Poor acoustic windows: Consider using contrast agents or transesophageal echocardiography (TEE) if transthoracic images are inadequate 1
• M-mode measurement errors: Particularly in patients with abnormally shaped ventricles or segmental wall motion abnormalities 2
• Load-dependent indices: Diastolic function parameters are affected by loading conditions and require careful interpretation 2
• Overestimation of stenosis: Can occur with high heart rates, arrhythmias, and motion artifacts 1

By following this systematic approach to 2D echocardiography, clinicians can obtain comprehensive cardiac assessment that guides diagnosis and management decisions to improve patient outcomes.