ABSTRACT
Objective: 1) To compare the efficacy of two drugs, Amlodipine and hydrochlorothiazide (HCTZ), in elderly Thai patients with isolated systolic hypertension (ISH) in terms of regression of left ventricular hypertrophy (LVH) and blood pressure control. 2) To detect the short (six months) and medium (18 months) terms of clinical outcomes of major cardiovascular events, i.e., congestive heart failure (CHF), myocardial infarction (MI), cerebrovascular disorders (CVD), death and minor clinical outcomes or adverse drug effects. This is a prospective randomized control study. Methods: From October 1997 to March 2000, 200 elderly patients with ISH, mean age of 69.3 years, were randomized into two groups, to receive either Amlodipine or HCTZ as a primary drug. Their baseline clinical data, blood chemistry, ECG, and echocardiography (ECHO) were evaluated. Regression of LVH was re-examined at six months; BP measurement was measured every 3 months for 18 months; and, clinical outcomes were followed at the end of study. Clinical end points were defined as death, myocardial infarction, and congestive heart failure. Results: Sixty-six percent of all patients had LVH by the ECHO criteria. After six months of monotherapy, there was regression of LVH in both groups (p < 0.01), but no difference in the reduction of LVMI between the two groups (p = 0.33). There was a significant reduction in BPsys in both treatment groups (p < 0.01). Those who received Amlodipine had more frequent side effects and were withdrawn from the study (p =0.02). The major adverse drug effect was leg edema (Amlodipine). However, more patients in the HCTZ group required additional drugs (Prazosin) in order to control BP to the desired level (39.2% vs 14.5%, p < 0.001). There was no statistical difference in clinical end points during follow-up. Difference of total drugs costs for one year of treatment was 8,084 Baht/patient in favor of the HCTZ regimen. Conclusion: It is suggested that a low dose of the HCTZ regimen is more cost effective when compared with Amlodipine and should be considered as the first antihypertensive agent of choice for ISH in the Thai elderly.
ABSTRACT
Mitral stenosis still remains a major problem in Southeast Asia including Thailand. It contributes to the morbidity and mortality related to thromboembolism which was associated with the left atrial thrombus. However, the pathogenesis of left atrial thrombus in these patients is not completely understood. Therefore, the objective of this study was to investigate the coagulation and platelet activity including the function of the endocardium in the left atrium and peripheral circulation in patients with mitral stenosis who were free of left atrial thrombus and to compare those hematologic markers activity in the peripheral venous blood between the patients with mitral stenosis and the control. Thirty-six patients with moderate to severe mitral stenosis were included in the study. Most of the patients were in functional class II and 50 per cent had atrial fibrillation. Blood was obtained from the femoral vein, femoral artery, pulmonary artery and left atrium of these patients before heparin was administered to determine the value of various hematologic markers. In the control group, blood for determining the hematologic markers was collected only from the antecubital vein. The results of this study demonstrated that the levels of prothrombin activation fragment 1+2 (F1+2), thrombin-antithrombin III complex (TAT) and Beta-thromboglobulin (beta-TG) in the left atrium of the patients with mitral stenosis were significantly higher than those in the femoral vein and femoral artery, whereas the level of thrombomodulin was significantly lower in the left atrium compared with the femoral artery and vein. When comparing with the control group, the levels of TAT, plasminogen activator inhibitors-1 (PAI-1) from the peripheral vein were significantly higher and the level of thrombomodulin was also significantly lower in the patients with mitral stenosis. In conclusion, the present study demonstrated an abnormal hypercoagulable state of the left atrium and systemic circulation related to the abnormalities of coagulation, platelets and the endocardium which may cause the formation of left atrial thrombus in patients with mitral stenosis.