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Dr. Jeff Hersh: When exercise takes your breath away

Dr. Jeff Hersh

Q: My 15-year-old daughter gets extremely short of breath when she does athletics, but otherwise does not seem to have any breathing problems. It has gotten so bad that she has had to withdraw from her soccer team. Her doctor treated her for asthma with an inhaler, but that did not help. She saw a pulmonary specialist who did a methacholine challenge test and other lung tests, and from this the specialist concluded she doesn't have asthma. Now they think she has Vocal Cord Dysfunction. What is this? Could this be her heart? Could it be asthma despite what they have said?

A: I will discuss Vocal Cord Dysfunction (VCD) today, but first let me address a couple of other issues you bring up.

Exercise-induced asthma is pretty common in kids, so it seems reasonable that this was the condition that was first suspected. Since her symptoms did not respond to a bronchodilator inhaler, and her methacholine test and lung functions tests showed she did not have asthma according to her pulmonary doctor, asthma seems a very unlikely cause of her symptoms.

Anything is possible in medicine, but an old article I found from Clinical Pediatrics looked at 180 children and adolescents with chest pain and/or shortness of breath associated with exercise, and found that none of them had heart abnormalities. Despite this, it is reasonable to have an exercise test done. Let me explain why.

There are many things that can cause exercise-induced shortness of breath in children/adolescents, including exercise-induced hyperventilation (where someone breaths faster and deeper than needed due to stress, anxiety or other reasons), supraventricular tachycardia (SVT, where the heart goes extremely fast due to the electrical circuits in the heart functioning abnormally), VCD, and others (e.g., laryngeal spasm, foreign body obstruction, laryngomalacia).

Evaluating someone while they have their symptoms is often very revealing of the cause of those symptoms, so an exercise test is a logical next step.

VCD is when the vocal cords inappropriately close during respiration, causing obstruction. This little-known condition is more common than many suspect; it is diagnosed in up to 10 percent of patients referred for asthma who don't respond to aggressive treatment. It is more common in females and can occur at any age, although it is most common in adolescents and young adults.

Typical symptoms of VCD include shortness of breath (often with exertion), wheezing and cough, similar to asthma. However, VCD symptoms do not respond to asthma medications, and this is often when the diagnosis is suspected.

VCD can be triggered by acid reflux, respiratory irritants and exercise, as well as other possible triggers. VCD is best diagnosed by evaluating the patient during an attack. At these times, lung functions tests, and even more specifically direct visualization of the vocal cords by an ear, nose and throat (ENT) specialist, can confirm the diagnosis.

If a trigger of VCD can be identified for a particular patient, avoidance of the trigger or treatment to minimize its affects (such as treatment for acid reflux) can be useful. Treatment specifically for VCD revolves around teaching the patient to relax their vocal cords during an attack. A speech therapist familiar with this condition can teach the patient relaxation and breathing exercises (such as controlled and relaxed exhalations, relaxation of the shoulder muscles and use of diaphragm and abdominal muscles). For some patients behavioral psychotherapy can also be useful. I found one reference that noted efficacy for exercise-induced VCD with the inhaled anticholinergic medication ipratropium bromide.

For patients with good response to these treatments, the prognosis is good, and most of these responders can return to their athletic activities. For non-responders, other treatments, such as injection of botulinum toxin, have been used, although efficacy of these treatments is variable. I could not find much on the long-term follow-up of adolescents diagnosed with VCD, but one limited study I did find noted that almost all of the patients had resolution of symptoms within about three years.

Patients who have been diagnosed with asthma but who have had no improvement despite aggressive asthma therapy may need evaluation for possible VCD. Consultation with a speech therapist that has expertise treating this condition is indicated once the diagnosis has been confirmed.

Jeff Hersh, Ph.D., M.D., F.A.A.P., F.A.C.P., F.A.A.E.P., can be reached at DrHersh@juno.com.