The effect of hyperhomocysteinemia on aortic distensibility in healthy individuals.

OBJECTIVE

Elevated plasma homocysteine (HCY) levels have been associated with increased risk for cardiovascular disease. Aortic distensibility and aortic pulse wave velocity (PWV) are indices of aortic elasticity. The potential effect of acute hyperhomocysteinemia (HHCY) on the elastic properties of the aorta in healthy individuals is not known. The aim of the present study was to determine the effect of acute methionine-induced HHCY on aortic distensibility and PWV in healthy individualsand the effect of acute HHCY on myocardial performance of the left ventricle (Tei index).

METHODS

Thirty healthy volunteers were included in this crossover study. An oral methionine (100 mg/kg) or water load was given in random order on separate days at weekly intervals. Aortic distensibility and Tei index were determined non-invasively by ultrasonography at baseline and 3 h after methionine or water consumption, while PWV was measured by applanation tonometry at baseline and every 1 h for the same time interval.

RESULTS

Oral methionine induced an increase in total plasma HCY concentrations (P < 0.001), whereas HCY concentrations did not change after water consumption. Aortic distensibility decreased 3 h after methionine load (P < 0.001) and Tei index increased (P < 0.001), suggesting worsening compared with baseline values. Water consumption had no effect on aortic distensibility or Tei index values. PWV values did not change after either methionine or water consumption.

CONCLUSIONS

Acute methionine-induced HHCY reduces aortic distensibility and worsens myocardial performance in healthy individuals. Further research is warranted to examine in the long term the direct effects of HHCY on cardiovascular function and the indirect effects on structural remodeling.