"

Parasternal Views

Bailey Freeman, DNP, CRNA and Angela Mordecai

Quick Facts
Procedure
Confirmation Steps
Documentation Requirements
Scope Guide

Quick Facts

  • First-line views in many cardiac POCUS protocols
  • Provide optimal visualization of left ventricular function
  • Allow assessment of valvular structures (particularly mitral, aortic)
  • Generally easier to obtain than apical views

 

Indications

Parasternal views in cardiac POCUS are indicated for:

  • Assessment of left ventricular function
  • Evaluation of valvular pathology
  • Screening for pericardial effusion
  • Assessment of left ventricular wall thickness

 

Absolute Contraindications

  • No specific contraindications beyond general POCUS limitations

 

Relative Contraindications

  • May be difficult in patients with COPD
  • Challenging in obesity
  • Limited by chest wall deformities

Procedure

 

Equipment Needed:

  1. Cardiac (phased array) probe
  2. Ultrasound gel
  3. Patient in supine or left lateral decubitus position
  4. Ultrasound machine with cardiac preset

Parasternal View Technique

PARASTERNAL LONG AXIS (PLAX)

  1. Position patient in supine or left lateral decubitus position
  2. Place probe at 3rd-4th intercostal space, left sternal border
  3. Direct indicator toward patient’s right shoulder
  4. Adjust depth to include all cardiac structures including pericardium
  5. Fine-tune by sliding probe between intercostal spaces
  6. Use “heel-toe” tilting motion to optimize image

 

PARASTERNAL SHORT AXIS (PSAX)

  1. From PLAX position, rotate probe 90° clockwise
  2. Direct indicator toward patient’s left shoulder
  3. Maintain same intercostal space initially
  4. Adjust position to visualize different levels:
    • Base (valvular level)
    • Mid-papillary muscle level
    • Apical level
  5. Tilt probe to sweep from base to apex

 

OPTIMIZATION TECHNIQUES

  1. Have patient briefly hold breath at end-expiration
  2. Adjust probe pressure for optimal contact
  3. Try different intercostal spaces if needed
  4. Adjust patient position for better windows

 

View-Specific Imaging Details

PARASTERNAL LONG AXIS

Anatomy Visualized

  • Structures seen:
    • Left ventricle
    • Right ventricle (anterior portion)
    • Left atrium
    • Aortic valve
    • Mitral valve
    • Aortic root and proximal ascending aorta
    • Pericardium
  • Normal proportions:
    • Left atrium approximately 1/3 of view
    • Aortic root approximately 1/3 of view
    • Right ventricle approximately 1/3 of view

Clinical Assessment

  • Function evaluation:
    • LV contractility
    • Anterior and posterior wall motion
    • Interventricular septal motion
  • Structural assessment:
    • Chamber sizes
    • Wall thickness
    • Valve morphology and function
    • Pericardial space
Long Axis Echo Probe Position and Anatomy. Adapted from “Basic Cardiac Point-of-Care Ultrasound” by Matthew Lipton, MD is licensed under CC BY 4.0

 

PARASTERNAL SHORT AXIS

Anatomy Visualized

  • Base level:
    • Aortic valve (circular with three cusps)
    • Tricuspid valve
    • Pulmonic valve
    • Right ventricular outflow tract
  • Mid-papillary level:
    • Circular left ventricle
    • Papillary muscles
    • Right ventricle (crescent shape)
  • Apical level:
    • Smaller circular left ventricle
    • Apex of heart

Clinical Assessment

  • Function evaluation:
    • Global and regional wall motion
    • Symmetry of contraction
    • Papillary muscle motion
  • Structural assessment:
    • LV size and shape
    • RV size and shape
    • Wall thickness
    • Valve morphology at base level

 

Short Axis Echo Probe Position and Anatomy. Adapted from “Basic Cardiac Point-of-Care Ultrasound” by Matthew Lipton, MD is licensed under CC BY 4.0

 

Confirmation Steps

PLAX CONFIRMATION

  • Verify key structures:
    • LV, RV, LA all visible
    • Aortic and mitral valves visualized
    • Pericardium identified
  • Correct orientation:
    • Apex to the left of screen
    • Base to the right
    • True long axis view of LV
  • Rule of thirds applied:
    • LA, aortic root, and RV approximately equal size

PSAX CONFIRMATION

  • Verify circular LV:
    • True short axis with symmetrical appearance
    • Papillary muscles identified at mid-level
    • RV appears as crescent shape
  • Base level confirmation:
    • Aortic valve with three cusps visible
    • Surrounding structures identified
  • Mid-level confirmation:
    • Both papillary muscles visualized
    • Circular, symmetrical LV

 

Documentation Requirements

  • Images at end-systole and end-diastole
  • Views showing relevant pathology
  • Measurements if performed (LV dimensions, wall thickness)
  • Multiple PSAX levels when relevant
  • Video clips showing dynamic function


SCOPE GUIDE

Strategies & Clinical Optimization

Image Optimization Techniques

  • Patient positioning
    • Left lateral decubitus position improves windows
    • Proper breathing instructions (end-expiration hold)
    • Slight elevation of left side of chest
  • Probe adjustments
    • “Heel-toe” tilting motion
    • Gentle but firm pressure
    • Minimal movements between intercostal spaces
  • Machine settings
    • Appropriate depth
    • Focused gain adjustment
    • Use of harmonic imaging when available

Troubleshooting Poor Windows

  • Alternative approaches
    • Try one intercostal space higher or lower
    • Request deeper inspiration or expiration
    • Adjust probe frequency if available
  • Special populations
    • COPD: Try more lateral approach
    • Obesity: Use more pressure, lower frequency
    • Elderly: Account for calcifications
  • Technical factors
    • Ensure adequate gel application
    • Optimize room lighting
    • Proper probe grip technique

Assessment Tips

  • Functional evaluation
    • Compare end-diastolic to end-systolic volumes
    • Look for wall thickening during systole
    • Assess all visible segments
  • Rule of thirds application
    • Visual estimation of chamber proportions
    • Assessment of LA dilation
    • RV size evaluation

 

Pearls

  • PLAX is excellent for LV function, aortic/mitral valve assessment
  • PSAX at mid-papillary level is ideal for global LV function assessment
  • Look for symmetrical contraction of all LV segments
  • A normal heart will reduce its cavity size by more than half during systole
  • Maintain probe position over intercostal space to avoid rib shadowing

Key Observations

  • Normal findings:
    • Symmetric LV contraction
    • Thin, well-defined valve leaflets
    • No pericardial effusion
    • Proportional chambers
  • Pathologic findings:
    • Wall motion abnormalities
    • Chamber enlargement
    • Wall thickness changes
    • Valve abnormalities
    • Pericardial effusion
  • Technical tips:
    • Slow, controlled probe movements
    • Use anatomical knowledge to predict structures
    • Compare findings between views

Quick Resources

Key Measurements

  • Normal LV diastolic diameter: 3.5-5.6 cm
  • Normal septal wall thickness: 0.6-1.0 cm
  • Normal LV posterior wall thickness: 0.6-1.0 cm
  • Normal LA diameter: 2.7-3.8 cm

Key Images/Diagrams

 

 

Parasternal long axis view. Turn the probe indicator towards the right shoulder. LV, Left ventricle; RV, Right ventricle; AV, Aortic valve; LVOT, Left ventricle outflow tract; MV, Mitral Valve. Clips created with the use of Z-anatomy.

 

Anatomical Views

  • PLAX landmark structures
  • PSAX levels comparison
  • Rule of thirds diagram
  • Normal chamber proportions

Critical Angles

  • Proper probe positions
  • Sweeping technique visualization
  • Probe rotation angles
  • Heel-toe adjustment technique

References

1. American Society of Echocardiography guidelines for chamber quantification
2. International consensus guidelines on cardiac POCUS

Media Attributions

License

Icon for the Creative Commons Attribution-NonCommercial 4.0 International License

The Scope Copyright © by Bailey Freeman, DNP, CRNA and Angela Mordecai is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, except where otherwise noted.

Share This Book