What does an Rv (Respiratory Volume) ap (airway pressure) of 43 millimeters indicate?

RV ap 43 millimeters Indicates Right Ventricular Enlargement

RV ap 43 millimeters indicates moderate right ventricular enlargement, which is an important echocardiographic finding that may suggest right-sided heart pressure overload or pulmonary hypertension. 1

Understanding Right Ventricular Measurements

• RV ap refers to the right ventricular anterior-posterior dimension, which is a standard echocardiographic measurement used to assess right ventricular size 1
• Normal RV dimension is ≤33 mm when measured from the apical four-chamber view 1
• A measurement of 43 mm indicates moderate enlargement of the right ventricle, exceeding the accepted cut-off value for normal RV size 1

Clinical Significance

• RV enlargement is often associated with:

  • Right ventricular pressure overload, as seen in pulmonary hypertension 1
  • Right ventricular volume overload, as seen in significant tricuspid or pulmonary regurgitation 1
  • Right ventricular dysfunction 1

• In the context of the case described in the evidence, this finding was associated with:

  • Severe hypokinesia of the mid-free wall of the right ventricle 1
  • McConnell sign (normally contracting RV apex with mid-free wall hypokinesia) 1
  • Elevated RV systolic pressure of 50 mm Hg 1
  • Pulmonary embolism, which was later confirmed by CT imaging 1

Associated Echocardiographic Findings to Consider

When RV enlargement is present, additional echocardiographic parameters should be evaluated:

• Tricuspid regurgitation velocity to estimate pulmonary artery systolic pressure 1
• RV function parameters such as:
  • Tricuspid annular plane systolic excursion (TAPSE) 1
  • RV fractional area change (normal >32%) 1
  • Interventricular septal flattening or "D-shaped" left ventricle 1
• Right atrial size (normal maximal volume ≤33 mL/m²) 1
• Inferior vena cava diameter and collapsibility (normal diameter <2.1 cm) 1

Differential Diagnosis Based on RV Enlargement

• Pulmonary embolism (acute or chronic) 1
• Pulmonary hypertension (various groups) 1
• Significant tricuspid regurgitation 1
• Right ventricular cardiomyopathy 1
• Congenital heart disease with right-sided volume or pressure overload 1
• Chronic lung disease with cor pulmonale 2

Clinical Approach When RV Enlargement is Detected

• Assess for symptoms of right heart failure or pulmonary hypertension 1
• Evaluate for potential causes:
  • Consider pulmonary embolism, especially with acute onset 1
  • Assess for chronic lung diseases that may lead to pulmonary hypertension 2
  • Look for valvular heart disease, particularly involving right-sided valves 1
• Additional diagnostic testing may include:
  • Complete echocardiographic assessment of right heart function and pulmonary pressures 1
  • CT pulmonary angiography if pulmonary embolism is suspected 1
  • Right heart catheterization for definitive diagnosis of pulmonary hypertension 1

Pitfalls and Caveats

• RV measurements are highly dependent on the imaging plane and technique used 1
• A single measurement should not be interpreted in isolation but in the context of other clinical and echocardiographic findings 1
• In acute right ventricular pressure overload (e.g., acute pulmonary embolism), the RV may not have time to dilate significantly despite severe hemodynamic compromise 1
• Respiratory variations can affect RV measurements, so images should be acquired during end-expiration when possible 1