Seara Francisco Javier García, Juanatey José Ramón González, Sande José Luis Martínez, Veloso Pedro Rigueiro, Reino Antonio Pose, Román Alfonso Varela, Cerrato José Cabezas, Peña Miguel Gil de la
Cardiology Department, Hospital Clínico Universitario de Santiago de Compostela, Spain.
Ann Noninvasive Electrocardiol. 2003 Jan;8(1):47-54. doi: 10.1046/j.1542-474x.2003.08108.x.
We report the reduction of QT and QTc dispersion in patients treated for 7 years with enalapril for systemic hypertension with left ventricular (LV) hypertrophy. We assess the correlation between QT dispersion and LV mass during this period and at the end of an 8-week period of suspension of enalapril treatment after 5 years.
Twenty-four previously untreated patients with this condition took enalapril (20 mg twice daily) for 7 years, except during an 8-week period following 5-year follow-up. Cardiovascular parameters were determined by two-dimensional guided M-mode echocardiography, and QT interval was measured, in a pretreatment placebo phase, 8 weeks and 1, 3, 5, and 7 years after the start of the therapy, at the end of the 8-week suspension effected after 5 years, and 8 weeks after the end of the suspension.
Therapy rapidly reduced blood pressure (BP) from 156/105 mmHg to normal values: 134/84 mmHg after 8 weeks' treatment, 130-84 mmHg at 7-year follow-up (P < 0.001 with respect to the placebo phase). LV mass index decreased progressively until at 5-year follow-up the reduction had reached 39% (P < 0.001), after which neither LV mass nor any other structural parameter underwent any further significant change. During this time, QT dispersion (DeltaQT) and the dispersion of "corrected" QT (DeltaQTc) decreased significantly: DeltaQT (from 61 +/- 21 to 37 +/- 13 ms) and DeltaQTc (from 67 +/- 27 to 41 +/- 16 ms). After suspension of treatment for 8 weeks following 5-year follow-up, DeltaQT was 40 +/- 14 ms and DeltaQTc was 44 +/- 17 ms; there were no significant changes either in DeltaQT and DeltaQTc or LV hypertrophy although BP had returned to pretreatment values (BP: 150 +/- 16; 101 +/- 10 mmHg).
Long-term enalapril treatment of hypertensive patients with LV hypertrophy induces marked regression of LV mass and improvement of QT dispersion. These improvements occur on a longer timescale than improvement in BP, and are not affected by transient changes in BP values.
我们报告了使用依那普利治疗系统性高血压伴左心室（LV）肥厚7年的患者QT和QTc离散度降低的情况。我们评估了在此期间以及5年后停用依那普利治疗8周结束时QT离散度与左心室质量之间的相关性。
24例此前未接受过治疗的此类患者服用依那普利（每日两次，每次20mg）7年，但在5年随访后的8周期间除外。通过二维引导M型超声心动图测定心血管参数，并在治疗前安慰剂阶段、治疗开始后8周、1年、3年、5年和7年、5年后8周停药结束时以及停药结束后8周测量QT间期。
治疗迅速将血压（BP）从156/105mmHg降至正常水平：治疗8周后为134/84mmHg，7年随访时为130/84mmHg（相对于安慰剂阶段，P<0.001）。左心室质量指数逐渐下降，直至5年随访时下降了39%（P<0.001），此后左心室质量和任何其他结构参数均未发生进一步的显著变化。在此期间，QT离散度（DeltaQT）和“校正”QT离散度（DeltaQTc）显著降低：DeltaQT（从61±21降至37±13ms）和DeltaQTc（从67±27降至41±16ms）。5年随访后停药8周，DeltaQT为40±14ms，DeltaQTc为44±17ms；尽管血压已恢复到治疗前水平（血压：150±16；101±10mmHg），但DeltaQT、DeltaQTc或左心室肥厚均无显著变化。
长期使用依那普利治疗高血压伴左心室肥厚患者可使左心室质量显著消退并改善QT离散度。这些改善发生的时间尺度比血压改善的时间尺度更长，且不受血压值短暂变化的影响。
