Small- and moderate-size right-to-left shunts identified by saline contrast echocardiography are normal and unrelated to migraine headache.
BACKGROUND
We suspected, based on clinical experience, that the prevalence of both intracardiac and pulmonary arteriovenous malformations (PAVMs) is higher than previously reported in a healthy population when using modern ultrasound technology combined with a rigorous saline contrast echocardiogram (SCE) protocol. We hypothesized the prevalence of right-to-left shunts (RLSs) would be so high when using this sensitive technique that there would be no significant association of RLS with migraine headache.


METHODS
We recruited 104 healthy volunteers to undergo an SCE followed by completion of a migraine questionnaire. The SCEs were meticulously graded for shunt size and location based on left-sided heart contrast quantity and timing. The migraine headache questionnaire was graded by a neurologist blinded to SCE results.


RESULTS
One hundred four subjects underwent the study protocol. We found 71% of subjects exhibited evidence of RLS. Patent foramen ovale (PFO) was identified in 40 (38%), PAVM was identified in 29 (28%), and five subjects had evidence of both (5%). Based on questionnaires, 42 (40%) of the subjects had migraine headache (29% with aura). There was no significant association of migraine headache with PFO (OR, 0.59; 95% CI, 0.16-2.12; P = .54) or PAVM (OR, 0.8; 95% CI, 0.34-1.9; P = .67), although only 13 (13%) of the subjects had evidence of large RLS.


CONCLUSIONS
When using modern ultrasound technology combined with a rigorous SCE technique, the majority of healthy subjects demonstrate some degree of RLS. PAVM in an otherwise healthy population is common. Small- and moderate-size RLSs do not appear to be significantly associated with migraine headache.
Department of Internal Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA. twoods@mcw.edu
Timothy D
TD
Woods
Leanne
L
Harmann
Traci
T
Purath
Suresh
S
Ramamurthy
Sharath
S
Subramanian
Scott
S
Jackson
Sergey
S
Tarima
D000293:Adolescent; D000328:Adult; D001165:Arteriovenous Malformations / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003287:Contrast Media; D004452:Echocardiography; D005260:Female; D054092:Foramen Ovale, Patent / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008171:Lung Diseases / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000150:complications* / Q000175:diagnosis; D012965:Sodium Chloride; D011795:Surveys and Questionnaires; D055815:Young Adult
D003287:Contrast Media; D012965:Sodium Chloride