Background: Ambulatory Blood Pressure Monitoring may improve the risk/benefit ratio of treatments in advanced systolic heart failure by detecting impact of medical treatment on circadian variability of BP. Objective: To evaluate the circadian variability of blood pressure in patients with advanced systolic heart failure and impact of medical treatment. Methods: Prospective controlled study. We studied 28 patients with NYHA functional class IV congestive heart failure. Twenty four hour AMBPM was performed twice (at decompensation stage NYHA class IV and compensation stage NYHA class II) and data of both readings were analyzed and detection of LV contractility by ECHO. Results: .Three deaths occurred after the 1st reading and four deaths occurred after the 2nd reading. Twenty two patients (78.6%) are male. Mean age of the patients was 55.3±13.2 years, 15 patients (53.6%) are hypertensive, 12patients (42.9%) are diabetic, 18 patients (64.3%) are smoker and 10 patients (35%) have positive family history of idiopathic cardiomyopathy. Systolic BP dipping (SBP dipping) improved and became after medical treatment (1%-9%) in10 patients (55.5%) , (>9%) in 3 patients (16.6% ) and became (<1%) in 5 patients(27.7%) with improvement . Diastolic BP dipping(DBP dipping) improved and became after medical treatment (1%-9%) in10 patients (55.5%) , (>9%) in 4 patients (22% ) and became (<1%) in 3 patients(16.6%) with improvement.SBP dipping and DBP dipping improved after medical treatment by statistically significant p value ( P value=0.001and P value=0.019) respectively. Pt with SBP dipping -3.00 ± 4.97% related strongly to survival by significant P value (0.02). Conclusion: Medical treatment restored some degree of autonomic control in patients with CHF, as reflected by improvement of circadian patterns of blood pressure and reaching to a near normal variability of circadian patterns of blood pressure.