Pulmonary Stenosis

Preliminary Diagnosis: Pulmonary Stenosis

I. What imaging technique is first-line for this diagnosis?

Trans-thoracic 2D echocardiography.

II. Describe the advantages and disadvantages of this technique for diagnosing pulmonary stenosis.

Advantages

• Offers exquisite anatomical and functional imaging.

• Does not expose patients to ionizing radiation.

• Helps detect pressure gradients and velocities across a diseased valve and helps guide treatment.

Disadvantages

• Operator dependent.

III. What are the contraindications for the first-line imaging technique?

No specific contraindications exist.

IV. What alternative imaging techniques are available?

• PA and lateral view of the chest.

• CTA.

• MR/MRA of the heart.

• Conventional cardiac catheter angiography.

V. Describe the advantages and disadvantages of the alternative techniques for diagnosing pulmonary stenosis.

PA and lateral view of the chest

Advantages

• Relatively inexpensive, portable imaging modality.

• Exposes patients to negligible ionizing radiation.

Disadvantages

• Moderately sensitive and poorly specific in detecting and diagnosing pulmonary stenosis.

• Does not allow for adequate delineation of the surrounding anatomical structures.

CTA

Advantages

• Offers exquisite detail of the anatomical structures, including vascular, soft tissue, lymphatic, and osseous structures.

Disadvantages

• Exposes patients to ionizing radiation.

• Does not allow for therapeutic intervention.

• Useful for evaluating supravalvular and peripheral pulmonary stenosis.

MR/MRA of the heart

Advantages

• Does not expose patients to ionizing radiation.

• Useful for evaluating supravalvular and peripheral pulmonary stenosis.

Disadvantages

• Expensive.

• Time consuming.

• Offers less exquisite detail of the surrounding vascular structures.

• May be subject to motion and susceptibility weighted image artifact.

• Must be cardiac gated.

Conventional cardiac catheter angiography

Advantages

• Offers exquisite detail of the cardiac valvular architecture and helps detect any other coexisting abnormalities.

• Allows for diagnosis and therapeutic intervention simultaneously.

Disadvantages

• Exposes patients to greater morbidity and mortality secondary to the invasive nature of the exam.

• Exposes patients to large amounts of ionizing radiation.

VI. What are the contraindications for the alternative imaging techniques?

PA and lateral view of the chest

• No specific contraindication. Some institutions may have pregnant patients sign consent

CTA

• May be contraindicated in pregnant patients.

• Relative contraindication in patients with renal failure and contrast allergy

MR/MRA of the heart

• Contraindicated in patients with non-MR compatible hardware.

Conventional cardiac catheter angiography

• Contraindicated in patients who are in a severe hypocoaguable state.