[Effect of pulse wave velocity on coronary flow reserve in patients with essential hypertension].

Objective: To observe the effect of pulse wave velocity (PWV) on coronary flow reserve (CFR) in patients with essential hypertension (EH).

Methods: 108 patients with EH were divided into three groups according to the blood pressure (BP) status and antihypertensive drug therapy (ADT): group A (n = 41, with ADT and BP failing to reach the standard), group B (n = 27, with high BP and without ADT), and group C (n = 40, with ADT and BP reaching the standard). Twenty-five sex, age, body mass index, waist/hip ratio, heart rate, fasting glycemia and lipid level-matched healthy persons were used as controls (group D). PWV, CFR, left ventricle mass index (LVMI), E/A ratio, left ventricle isovolumetric relaxation time (IVRT), left ventricular ejection fraction (LVEF) were detected in each group. Correlation analysis was conducted.

Results: (1) the PWV values in group A, B, and C were 12.7 m/s +/- 1.3 m/s, 11.9 m/s +/- 2.2 m/s, and 9.6 m/s +/- 0.9 m/s respectively, all significantly higher than that in the group D (8.9 m/s +/- 0.7 m/s, all P < 0.05) and with significant differences between group A and group C and between group B and group C (both P < 0.05). The CFR values in group A, B, and C were 2.56 +/- 0.18, 2.54 +/- 0.19, and 2.97 +/- 0.19 respectively, all significantly lower than that in group D (3.26 +/- 0.26, all P < 0.05), with significant differences between group A and group C and between group B and group C (both P < 0.05). The values of average peak velocity of baseline (APVb) in groups A, B, and C were 38 cm/s +/- 4 cm/s, 36 cm/s +/- 4 cm/s, and 34 cm/s +/- 4 cm/s respectively, significantly higher than that in group D (29 cm/s +/- 4 cm/s, all P < 0.05), without significant difference among group A, B, and C. (2) The values of LVMI in group A, B, and C were 117 g/m(2) +/- 8 g/m(2), 113 g/m(2) +/- 11 g/m(2), and 98 g/m(2) +/- 11 g/m(2) respectively, all significantly higher than that of group D (88 g/m(2) +/- 7 g/m(2), all P < 0.05), with significant differences between group A and group C and between group B and group C. The E/A ratios in groups A and B were 0.76 +/- 0.19 and 0.87 +/- 0.18 respectively, significantly lower than those in group C and D (1.08 +/- 0.18 and 1.19 +/- 0.15 respectively, all P < 0.05). The values of IVRT in group A, B and C were 134 ms +/- 11 ms, 138 ms +/- 11 ms, and 109 ms +/- 12 ms respectively, all significantly higher than that in group D (84 ms +/- 12 ms, all P < 0.05) with a significant difference between group A and group C and between group B and group C (both P < 0.05). There was no significant difference of LVEF among different groups. (3) Stepwise linear regression of PWV showed that the factors significantly influencing PWV were age, LVMI, E/A ratio and SBP, the factors significantly influencing CFR were LVMI and PWV, and PWV was significant negatively correlated to CFR and significant positively correlated to APVb.

Conclusion: PWV is increased in hypertensive patients. The increase of LVMI and increase of PWV contribute to the decrease of CFR in hypertensive patients. Increase of PWV that attributes to left ventricular hypertrophy and decrease of E/A ratio in patients with hypertension leads to further decrease of CFR. Decrease of CFR in hypertensive patients may cause cardiovascular diseases. Early detection and prevention of increased PWV may decrease the morbidity of cardiovascular diseases.