Increased lipoprotein(a) is associated with reduced myocardial vasoreactivity in young healthy men.
OBJECTIVE
We examined the association between lipoprotein(a) and myocardial vasoreactivity in healthy men.


METHODS
Thirty non-smoking healthy men (age 34+/-6 years) were studied: 9 had increased lipoprotein(a) (>200 mg/L) concentrations (lipoprotein(a) 317 (range 218-550) mg/L) and 21 had normal lipoprotein(a) (<200 mg/L) concentrations (lipoprotein(a) 57 (range 13-156) mg/L). The myocardial blood flow measurements were performed basally and during adenosine infusion (140 microg/kg/min) with or without simultaneous physiological hyperinsulinemia (insulin infusion at a rate of 1 mU/kg/min) using positron emission tomography and [(15)O]H(2)O.


RESULTS
Basal myocardial blood flow was similar between the subjects with increased and normal lipoprotein(a) (0.76+/-0.20 and 0.79+/-0.20 mLg(-1) min(-1), NS). Adenosine-stimulated flow tended to be reduced in subjects with increased lipoprotein(a) (3.1+/-0.7 mLg(-1) min(-1) versus 3.7+/-1.1 mLg(-1) min(-1), respectively, p=0.1). During physiological hyperinsulinemia adenosine-stimulated flow was further enhanced in both groups but significantly blunted in subjects with increased lipoprotein(a) (3.7+/-0.8 mLg(-1) min(-1) versus 4.8+/-1.4 mLg(-1) min(-1), respectively, p=0.03). This difference remained significant after simultaneous controlling for BMI, HbA1c, LDL-cholesterol, HDL-cholesterol and blood pressure (p=0.04).


CONCLUSIONS
Already young healthy men with lipoprotein(a) concentrations greater than 200mg/L are characterized by impaired myocardial vasoreactivity.
Sundell
Jan
J
Turku PET Centre, Turku University Central Hospital, P.O. Box 52, FIN-20521 Turku, Finland. jan.sundell@utu.fi
Laine
Hanna
H
Raitakari
Olli T
OT
Luotolahti
Matti
M
Nuutila
Pirjo
P
Viikari
Jorma
J
Knuuti
Juhani
J
D000241:Adenosine / Q000008:administration & dosage; D000328:Adult; D001794:Blood Pressure; D003326:Coronary Circulation / Q000187:drug effects / Q000502:physiology*; D006339:Heart Rate; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood*; D008297:Male; D010104:Oxygen Radioisotopes; D049268:Positron-Emission Tomography; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*; D014665:Vasodilator Agents / Q000008:administration & dosage
D017270:Lipoprotein(a); D010104:Oxygen Radioisotopes; D014665:Vasodilator Agents; D000241:Adenosine