Impaired vascular function in patients with Fontan circulation.
BACKGROUND
This study was performed to evaluate the endothelial function in Fontan patients, and to investigate the associated factors which influence the endothelial function in these patients.


METHODS
Flow mediated dilatation (FMD) and nitroglycerin induced dilatation (NG) of the brachial artery, and intima media thickness (IMT) of common carotid artery (CCA) were measured in nonselected Fontan patients (n=44, age 5 to 29 years, median 14 years, 18 females) by means of high-resolution ultrasound according to the standard protocols. The results were compared to age and sex matched controls (n=25, age 5 to 27 years, median 13 years, 10 females).


RESULTS
Fontan patients presented significantly reduced FMD and NG compared with controls (FMD; 6.5+/-2.4 vs. 11.1+/-1.4%, p<0.001, NG; 13.3+/-5.2 vs. 19.4+/-6.2%; p=0.035). Twenty two percent of Fontan patients presented pure endothelial dysfunction, and 34% of patients presented combined endothelial and smooth muscle dysfunction. Although there was no correlation between FMD and IMT, Fontan patients presented increased carotid IMT (0.44+/-0.07 vs. 0.38+/-0.06 mm, p=0.008). In multivariate analysis, duration of exposure to chronic hypoxia was inversely correlated with FMD (p=0.117, hazards ratio=1.294, 95% confidence interval=0.938-1.786). There was higher FMD in patients receiving angiotensin-converting enzyme inhibitors (ACEi) compared with those not receiving ACEi (7.0+/-2.5 vs. 5.5+/-2.2%, p=0.069).


CONCLUSIONS
Endothelial dysfunction is more prevalent in Fontan patients compared with healthy controls, and the previous hypoxia is an independent factor. Although it is not statistically significant, those patients on treatment with ACEi seem to have better endothelial function.
Jin
Seon Mi
SM
Department of Pediatrics, Eulji Medical Center, Eulji University, 280-1 Hagyedong, Nowongu, Seoul 139-711, South Korea.
Noh
Chung Il
CI
Bae
Eun Jung
EJ
Choi
Jung Yun
JY
Yun
Yong Soo
YS
D000286:Administration, Sublingual; D000293:Adolescent; D001783:Blood Flow Velocity / Q000187:drug effects / Q000502:physiology; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000503:physiopathology*; D017536:Carotid Artery, Common / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D003287:Contrast Media / Q000008:administration & dosage; D004730:Endothelium, Vascular / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D018729:Fontan Procedure; D006330:Heart Defects, Congenital / Q000150:complications / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008297:Male; D005996:Nitroglycerin / Q000008:administration & dosage; D011379:Prognosis; D012720:Severity of Illness Index; D018608:Ultrasonography, Doppler; D014652:Vascular Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*
D003287:Contrast Media; D005996:Nitroglycerin