Misra Kumar Haraprasad, Das Mangala Charana, Ramani Y Roja
Assistant Professor, Department of Pharmacology, MIMS , Vizianagaram, Andhra Pradesh, India .
J Clin Diagn Res. 2013 Jul;7(7):1352-5. doi: 10.7860/JCDR/2013/5416.3127. Epub 2013 Jul 1.
An increase in the Left Ventricular Mass as a result of muscle hypertrophy, has emerged as a powerful pressure independent risk factor for the cardiovascular mortality and morbidity. It is associated with a risk of death that is 3 times greater than the risk which is associated with hypertension alone. For the development of Left Ventricular Hypertrophy (LVH), in addition to a chronic increase in the pressure and/or volume overload, an elevation in the plasma ACE activity, plasma aldosterone levels, and the angiotensin-II concentrations play a major role .In this study, the effect of Telmisartan, a selective angiotension-II receptor blocker, was compared with that of Atenolol, a selective β1adrenergic receptor blocker, on the regression of LVH in the patients of essential hypertension.
Essential hypertensive patients with LVH were selected for this study, as per the inclusion and exclusion criteria. This study was carried out on two groups of hypertensive patients with LVH: Group-1: The patients who were taking telmisartan 80 mg OD. Group-2: The patients who were taking atenolol 50 mg OD. The blood pressure was measured and echocardiography was done in both the groups, prior to the treatment and 6 months after the treatment in the Department of Cardiology, MKCG Medical College Hospital, Brahmapur, India. The data were analysed by using the Student's 't' test.
In the cases of Left Ventricular Mass Index (LVMI), which is a better indicator of LVH, in the Atenolol group, the mean value changed from 143.93 ± 2.44 gm/m(2) to 130.16 ± 2.88 gm/m(2) (t=5.83,p<0.01versus baseline).In the Telmisartan group, the mean value changed from 184.67 ± 7.14 gm/m(2) to 133.41± 4.24 gm/m(2) (t=12.12, p<0.001versus baseline). On comparing Telmisartan with Atenolol, Telmisartan was found to produce a greater (27.49%) reduction than Atenolol (9.68%). In the Telmisartan group, 13 patients out of 26 patients achieved a target value of LVMI that was <134 gm/m(2) in males and <110 gm/m(2) in females (50%). In the Atenolol group, only 9 patients out of 22patients achieved a target value (40.90%).
Thus, Telmisartan a selective AT1antagonist, possesses pharmacological effects beyond a blood pressure reduction in which the blockade of the AT1receptor may lead to attenuation of the growth promoting action of Ang II. From this study, it is clear that Telmisartan is superior to Atenolol in achieving a regression of LVH, which is a better indicator of the cardiovascular morbidity and mortality.
因心肌肥厚导致的左心室质量增加，已成为心血管疾病死亡率和发病率的一个强大的、与压力无关的危险因素。它所关联的死亡风险比仅与高血压相关的风险高出3倍。对于左心室肥厚（LVH）的发展，除了压力和/或容量超负荷的慢性增加外，血浆ACE活性、血浆醛固酮水平和血管紧张素II浓度的升高也起主要作用。在本研究中，将选择性血管紧张素II受体阻滞剂替米沙坦与选择性β1肾上腺素能受体阻滞剂阿替洛尔对原发性高血压患者左心室肥厚消退的影响进行了比较。
根据纳入和排除标准，选择患有左心室肥厚的原发性高血压患者进行本研究。本研究针对两组患有左心室肥厚的高血压患者开展：第1组：每日服用80毫克替米沙坦的患者。第2组：每日服用50毫克阿替洛尔的患者。在印度布拉马普特拉的MKCG医学院医院心脏病科，于治疗前及治疗6个月后，对两组患者进行血压测量并进行超声心动图检查。数据采用学生t检验进行分析。
左心室质量指数（LVMI）是左心室肥厚的一个更好指标，在阿替洛尔组中，其平均值从143.93±2.44克/平方米变为130.16±2.88克/平方米（t=5.83，与基线相比p<0.01）。在替米沙坦组中，平均值从184.67±7.14克/平方米变为133.41±4.24克/平方米（t=12.12，与基线相比p<0.001）。将替米沙坦与阿替洛尔进行比较时，发现替米沙坦的降低幅度（27.49%）大于阿替洛尔（9.68%）。在替米沙坦组中，26名患者中有13名（50%）男性达到LVMI目标值<134克/平方米，女性<110克/平方米。在阿替洛尔组中，22名患者中只有9名（40.90%）达到目标值。
因此，选择性AT1拮抗剂替米沙坦具有降压以外的药理作用，其中AT1受体的阻断可能导致血管紧张素II促生长作用的减弱。从本研究可以清楚地看出，在实现左心室肥厚消退方面，替米沙坦优于阿替洛尔，而左心室肥厚是心血管发病率和死亡率的一个更好指标。
