Efficacy/Safety Study of Valsartan and Chlorthalidone Conjugate Treatment Compared to Simple Treatment for Hypertension

Inclusion Criteria: * Patient with diagnosis of arterial hypertension defined as: * Systolic blood pressure greater or equal to 140 and lower than 180 mmHg * Diastolic blood pressure greater or equal to 90 and lower than 110 mmHg * Non controlled patients with antihypertensive treatment (blood pressure values: Systolic blood pressure \> 140 mmHg and/or Diastolic blood pressure \> 90 mmHg) or patients antihypertensive treatment-naïve. * Likelihood of attending consultations according to the trial chronogram. * Informed Consent Signature. Exclusion Criteria: * Diagnosis of severe or malignant arterial hypertension defined as: * Systolic blood pressure greater or equal to 180 mmHg * Diastolic blood pressure greater or equal to 110 mmHg * Patients with secondary arterial hypertension of any etiology. * Pregnant women or women with childbearing potential who are not using appropriate contraception methods; women planning to become pregnant during the trial. * Patients with history of Acute Myocardial Infarction o Angina Pectoris within the 6 months prior to the trial initiation. * Diagnosis of Cerebrovascular Disease (CVD) o Transient Ischemic Attack (TIA) within the 6 previous months. * Patients with Severe Renal Disease defined by serum Creatinine levels higher than 1.5 mg/dl. * Diagnosed or suspected unilateral or bilateral renal artery stenosis. * History of non remitting cancer within the 5 years prior to the trial initiation. * Patients with Hypokalemia or Hyperkalemia. * Patients receiving Valsartan or Chlortalidone during the 14 previous days. * Patients with known hypersensitivity to Valsartan or Chlorthalidone. * Unstable patients with antecedent of hospitalization within the 4 days prior to their enrollment in the trial. * Patients with history of drugs and alcohol abuse within the last year. * Patients who have taken part in other clinical trial within the 4 weeks prior to the initiation of this research. * Patients with any other clinical condition that the investigator deems may affect the patient follow-up.