Chambers that are Border Forming on the PA Examination

 There are Two Basic Common Shapes of Cardiomegaly

CARDIOMEGALY – TWO BASIC TYPES -OVOID and TRIANGULAR
The ovoid form which suggests left ventricular dominance and triangular form which suggests right ventricular dominance.
Ashley Davidoff MD

The Ovoid Form of Cardiomegaly – Consider LVE

SHAPE OF THE LEFT VENTRICLE
The enlarged LV (a,b) is shaped like an oval and it is likened to a rugby ball or an American football placed on the field at kick off time. LVE on CXR is mostly assessed by an increased cardiothoracic ratio as well as the accentuation of the ovoid shape. (lower images c, d,e, f)
Ashley Davidoff MD

Vector of the Enlarging LV  – Rotate  Down and to the Left

VECTOR FOR LV ENLARGEMENT
DOWN AND OUT
The left ventricle (LV) enlarges in a posterior, downward and lateral direction resulting in the characteristic changes of LVE on CXR
Ashley Davidoff MD

Clinical  Exam – Focal LV Thrust

The Triangular Form of Cardiomegaly 

Consider RVE or any disease from the left side that may cause RVE eg mitral stenosis

TRIANGULAR SHAPED HEART – SUGGESTING RIGHT VENTRICULAR DOMINANCE.     MITRAL STENOSIS PULMONARY HYPERTENSION
71 year old Asian female with rheumatic heart disease dominated by calcific mitral stenosis mild MR, moderate tricuspid regurgitation and secondary pulmonary hypertension.
Ashley Davidoff MD

Note the Basic Shape of the RV is Triangular in almost all Views

Vector of the Enlarging RV – Rotate  Laterally to the Right

Clinical  Exam of the RV  – Diffuse Anterior Parasternal Heave

What about the Right Atrium (RA) and Right Heart Border?

The RA does not make much a statement on the frontal CXR unless very large

The Enlarged Right Atrium

The right atrium is the most difficult chamber to assess unless it is very large in which case it will manifest on the frontal CXR with a very large right paravertebral border.

• • enlarged, globular heart
  • narrow pedicle
  • gross enlargement of the right atrial shadow, i.e. increased convexity in the lower half of the right cardiac border
    • right atrial convexity is more than 50% of the cardiovascular height
    • right atrial margin is more than 5.5 cm from the midline

The Left Atrium

3 signs

• • Carinal Angle
  • Double Density
  • Filling in of the Left Atrial Appendage Bay

The Carina and the Carinal Angle

NORMAL FRONTAL CXR NORMAL ASYMMETRIC BRANCHING OF MAINSTEM BRONCHI
The normal CXR shows the characteristic asymmetric branching of the main stem bronchi. The right is short and stout and slightly more vertical while the left is long and thin and slightly more obtuse.
The normal carinal angle is between 40-80 degrees.
Ashley Davidoff MD

ASYMMETRIC BRANCHING PATTERN – RIGHT SHORT AND STOUT AND THE LEFT LONG AND THIN
CARINAL ANGLE – 40-80 degrees
Ashley Davidoff MD

 The Abnormal Carinal Angle

MITRAL STENOSIS WITH ENLARGED LEFT ATRIUM – WIDENED CARINAL ANGLE DOUBLE DENSITY ENLARGED LEFT ATRIAL APPENDAGE
The frontal CXR demonstrates findings consistent with mitral stenosis including a widened carinal angle (teal blue and black arc), a double density (red arc) and an enlarged left atrial appendage (maroon arc).
The overall shape of the heart is triangular suggesting right ventricular enlargement. A mitral valve prosthesis is in position
Courtesy of Radiopaedia

PARTS OF THE ENLARGED HEART ON  FRONTAL CXR  in MITRAL STENOSIS PULMONARY HYPERTENSION AND COR BOVINUM
71 year old Asian female with rheumatic heart disease dominated by calcific mitral stenosis mild MR, moderate tricuspid regurgitation and secondary pulmonary hypertension.
The frontal view shows an enlarged RA (light blue) characterized by a prominent right heart border. The right ventricle is enlarged as noted by the triangular shape of the cardiac silhouette, an the upturned (“proud breast”) appearance of the left heart border, both reminiscent of RVE. The left atrium is also significantly enlarged characterised by the widened carina and the straight heart border caused by a combination of atrial appendage enlargement and pulmonary hypertension.  The LV (maroon) is normal in size
Ashley Davidoff MD

The Shapes of the Heart in Health and Disease

From top left ti right and across the rows they are:  The normal heart , the “football” of LV enlargement the “triangle” or “proud breast” of RV enlargement, “snowman” of total anomalous pulmonary venous return,  big PA mogul of pulmonary hypertension,  “egg on its side” of D transposition of the great vessels,   “boot shaped” heart seen in both pulmonary atresia and Tetralogy of Fallot, the long smooth combined Ao and PA mogul that has a differential diagnosis of L transposition, absence of the pericardium, and juxtaposition of the atrial appendages, the box shaped large heart of Ebstein’s anomaly, dextrocardia , and the water bottle” heart of a large pericardial effusion. 07197 Images are  a combination of images from a personal collection and borrowed from the internet for educational purposes only. Some of the  sources are unknown and are used for educational  purposes alone 86774b02

Normal Pulmonary Artery

Pulmonary Hypertension