Different effects of temocapril and cadralazine on electrocardiographic voltages and left ventricular mass in patients with essential hypertension.

To assess whether electrocardiographic variables are useful to detect the regression of left ventricular (LV) mass after long-term antihypertensive treatment, we related electrocardiographic voltages to echocardiographic variables before and after treatment with an ACE inhibitor, temocapril (TEM), or direct vasodilator, cadralazine (CAD). Twenty-one patients with essential hypertension were treated with either TEM (n = 11) or CAD (n = 10) for one year. LV mass index (LVMI) by echocardiography and Sokolow-Lyon voltage (SV1 + RV5), Cornell voltage (RaVL + SV3) and RV5 + RV6 by standard 12-lead electrocardiographic voltages were determined before and after treatment. Both drugs decreased blood pressure to the same extent. Both Sokolow-Lyon voltage and RV5 + RV6 tended to decrease in the ACE group (40.0 +/- 9.4 to 37.2 +/- 9.4 mm and 44.7 +/- 13.5 to 41.7 +/- 11.7 mm, respectively, N.S.), but not in the CAD group (38.4 +/- 6.8 to 39.7 +/- 7.7 mm and 42.9 +/- 10.4 to 46.8 +/- 11.2 mm, respectively, N.S.). LVMI decreased in the ACE group (-24 +/- 22 g/m2), whereas it increased in the CAD group (37 +/- 27 g/m2, p < 0.01). Change in LVMI was correlated with the changes in RV5 + RV6 and Sokolow-Lyon voltage (r = 0.73, p < 0.01 and r = 0.70, p < 0.01, respectively), but not with that in Cornell voltage. These results indicated that the changes in voltage criteria of RV5 + RV6 and Sokolow-Lyon are useful to assess the change in LVM after antihypertensive treatment in patients with essential hypertension although voltage variables in electrocardiogram were not sensitive to detect changes in LVMI.