Familial hypercholesterolemia affects microvascular autoregulation in children.
OBJECTIVE
Familial hypercholesterolemia (FH) impairs macrovascular endothelial function in childhood and causes an increase of cardiovascular risk in later life. Whether microvascular function is affected in children with FH is unknown. The aim of this study was to investigate the impact of FH on microvascular autoregulation in children by post occlusive reactive hyperemia (PORH).


METHODS
PORH of the skin was assessed using laser Doppler fluxmetry. Baseline perfusion, biological zero, defined as no-flow laser Doppler signal during suprasystolic occlusion, peak perfusion after release of suprasystolic occlusion, as well as time to peak perfusion and recovery time, defined as time until baseline perfusion is resumed, were measured in 16 children, who were diagnosed with FH according to current guidelines, and in 91 healthy controls.


RESULTS
In children with FH, peak perfusion was higher (FH: 1.60±0.68 vs. controls: 1.26±0.50 AU [arbitrary units], p=0.02), recovery time was longer (110±42.61 vs. 83.18±35.08 s, p=0.01) and biological zero was lower than in controls (0.12±0.04 vs. 0.18±0.05 AU, p<0.001). Baseline perfusion and time to peak were not different between children with FH and controls (baseline perfusion: 0.43±0.21 vs. 0.38±0.15 AU, p=0.18; time to peak: 15.44±12.25 vs. 18.18±17.79 s, p=0.56).


CONCLUSIONS
For the first time the present study reveals an impact of FH on microvascular autoregulation in children: the differences of PORH between children with FH and controls indicate an affected autoregulation of microvascular blood flow in FH, which has its onset in childhood.
Department of Medicine II, Division of Angiology, Medical University of Vienna, Austria.
Oliver
O
Schlager
Kurt
K
Widhalm
Alexandra
A
Hammer
Aura
A
Giurgea
Christian
C
Margeta
Maria
M
Fritsch
Sonja
S
Zehetmayer
Renate
R
Koppensteiner
Michael E
ME
Gschwandtner
Andrea
A
Willfort-Ehringer
D000293:Adolescent; D001794:Blood Pressure; D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006706:Homeostasis; D006801:Humans; D006937:Hypercholesterolemia / Q000188:drug therapy / Q000235:genetics* / Q000503:physiopathology*; D006940:Hyperemia / Q000503:physiopathology*; D000960:Hypolipidemic Agents / Q000627:therapeutic use; D008297:Male; D055806:Microvessels / Q000503:physiopathology*; D012867:Skin / Q000098:blood supply
D000960:Hypolipidemic Agents