J Cardiovasc Ultrasound.  2014 Jun;22(2):88-90. 10.4250/jcu.2014.22.2.88.

Exercise-Induced Intrapulmonary Arteriovenous Shunt in a Patient Complaining of Dyspnea during Strenuous Exercise

• Kim TJ
• Kim SA
• Hong SE
• Jung DM
• Choi NY
• Kim YK
• Park SA
• Kim SY
• Park WJ

• KMID: 2177466
• DOI: http://doi.org/10.4250/jcu.2014.22.2.88

Abstract

A 51-year-old highly fit man presented for dyspnea with strenuous aerobic exercise. The patient was asymptomatic and all tests were normal at rest. With increasing exercise intensity, he suddenly complained of dyspnea and showed a severe exercise-induced hypoxemia with an excessive alveolar-arterial oxygen tension difference. In agitated saline contrast echocardiography at peak exercise, a large amount of left to right shunt was identified after > 5 cardiac cycles, which suggests the presence of exercise-induced intrapulmonary arteriovenous shunt in this patient.

Keyword

Exercise; Intrapulmonary shunt; Contrast echocardiography

MeSH Terms

Anoxia
Dihydroergotamine
Dyspnea*
Echocardiography
Exercise
Humans
Middle Aged
Oxygen
Dihydroergotamine
Oxygen

Figure

• 

  Fig. 1 The agitated saline contrast echocardiography at rest showed only a few microbubbles appearing in the left heart after 9 cardiac cycles from the onset of right heart opacification.

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  Fig. 2 Computed tomography of the chest (A) and pulmonary angiography (B) to assess the presence of intrapulmonary shunt, such as pulmonary arteriovenous malformation showed no significant abnormality.

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  Fig. 3 Agitated saline contrast echocardiography done at the time the patient complained of dyspnea revealed large amount of microbubbles appearing in the left atrium and lead to complete left heart opacification after > 5 cardiac cycles from the onset of right heart opacification.

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