Thursday, February 02, 2006

Radiology Thursday: Dyspnea and Training for a Marathon

This is a 29 year old woman who presents with a complaint of dyspnea while running. She is otherwise completely healthy and never has had any medical problems.
However, she did note some epidoses of episodic dyspnea as a child. She describes her physical activity as mostly sedentary until the last three years of her life when she took up running. Recently, she has been trying to increase her mileage in preparation for her first marathon. She can run about 5 miles at a time now, but will often have to stop at about 2 miles because of dyspnea. She states that she has not been increasing her pace.

What abnormality does this CXR suggest and how would you proceed?

5 comments - CLICK HERE to read & add your own!:

Jennings said...

The PA view is fairly unremarkable. Here are my random thoughts:
- There does not appear to be hyperinflation (8 intercostals and diaphragms not flat) but on the lateral the bases appear very dark so I was originally thinking about lower-lobe emphysema or bullae (i.e. A1AT) but this is probably a big over-call...
- The pulmonary arteries do not seem to be enlarged (in a young female with dyspnea I would worry about pulmonary hypertension either idiopathic or autoimmune-related).
- On the lateral there is very little in terms of retrosternal space. Could there be an issue with the anterior mediastinum?
- there are some scattered calcified nodes in the upper lung zones.

Baleeiro said...

She does have pectus excavatum with a little displacement of the cardiac silhouette to the left on the PA. It is usually asymptomatic but older patients or patients who are now more active (as in this case) may feel more aware of their limitation.
It can be associated with other conditions such as Marfan's though and maybe she has some underlying cardiac disease (such as an ASD) which may also explain the dyspnea.

Mendez said...

As Jennings correctly pointed out and Baleeiro affirmed, there is no retrosternal space.

She has pectus excavatum. The degree can be assessed by several different measurements by PA/LAT or chest CT. However, there is no good correleation between this measurement and symptoms.

Two measures that can be used are:

- <10cm between posterior border of sternum and anterior border of thoracic vertebra on lateral (she measures about 6.3cm)
- AP/transverse diameter on PA/LAT < 0.4 (she measures 0.25)

How would you proceed with evaluation?

Jennings said...

Does she show restriction on pulmonary function testing? If the PFT's showed restriction with normal MiP's and a normal HRCT, that would be good enough for diagnosis I would think.
I thought this condition was treatable (surgically)in the pediatric population because, but would it be too late by adulthood?

DKeena said...

A CPET would be helpful to get a better idea of the degree of physiologic compromise, and whether it is a respiratory or cardiac limitation. An echo (+/- exercise) would be helpful as well.

If there is a respiratory limitation on CPET with normal baseline PFT's- I would consider getting a methacholine challenge (or emperic Rx) to exclude bronchospasm before attributing it all to the pectus.