Effects of candesartan on cardiac sympathetic nerve activity in patients with congestive heart failure and preserved left ventricular ejection fraction.
OBJECTIVE
We sought to evaluate the effects of angiotensin receptor blocker (ARB) on cardiac sympathetic nerve activity (CSNA) in patients with congestive heart failure (CHF) with a preserved left ventricular ejection fraction (LVEF).


BACKGROUND
Approximately 50% of patients with CHF have preserved LVEF. It is reported that ARB therapy improves CSNA in CHF patients and reduced LVEF. However, the effect of ARB therapy on CSNA evaluated by iodine-123 meta-iodobenzylguanidine ((123)I-MIBG) scintigraphy has not been determined in CHF patients with preserved LVEF.


METHODS
We selected 50 patients with nonischemic CHF and LVEF >40% who were treated with standard therapy. Twenty-five patients were randomized to also receive candesartan, whereas the remaining 25 patients received placebo. The delayed heart/mediastinum count (H/M) ratio, delayed total defect score (TDS), and washout rate (WR) were determined by (123)I-MIBG scintigraphy before and six months after treatment. The LV end-diastolic volume and LVEF were determined by echocardiography, and the plasma brain natriuretic peptide (BNP) concentration was also measured.


RESULTS
In patients receiving candesartan, (123)I-MIBG scintigraphic and echocardiographic parameters were significantly improved after treatment. In contrast, there were no significant changes in these parameters in patients receiving placebo. There was a significant correlation between the changes in (123)I-MIBG scintigraphic findings and the percent change in BNP from baseline to six months in patients receiving candesartan (TDS: r = 0.587, p < 0.005; H/M ratio: r = -0.509, p < 0.01; WR: r = 0.602, p < 0.005).


CONCLUSIONS
Adding candesartan to standard therapy can improve CSNA and LV performance in CHF patients with preserved LVEF.
Kasama
Shu
S
Department of Cardiovascular Medicine, Gunma University School of Medicine, Maebashi, Japan. s-kasama@bay.wind.ne.jp
Toyama
Takuji
T
Kumakura
Hisao
H
Takayama
Yoshiaki
Y
Ichikawa
Shuichi
S
Suzuki
Tadashi
T
Kurabayashi
Masahiko
M
D019797:3-Iodobenzylguanidine / Q000627:therapeutic use; D000368:Aged; D000369:Aged, 80 and over; D047228:Angiotensin II Type 1 Receptor Blockers / Q000009:adverse effects / Q000627:therapeutic use*; D000959:Antihypertensive Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001562:Benzimidazoles / Q000009:adverse effects / Q000627:therapeutic use*; D001713:Biphenyl Compounds; D002306:Cardiac Volume / Q000187:drug effects; D004311:Double-Blind Method; D004359:Drug Therapy, Combination; D004452:Echocardiography; D005260:Female; D006321:Heart / Q000294:innervation*; D006333:Heart Failure / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000187:drug effects; D020097:Natriuretic Peptide, Brain / Q000097:blood; D013318:Stroke Volume / Q000187:drug effects*; D013777:Tetrazoles / Q000009:adverse effects / Q000627:therapeutic use*; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome; D016277:Ventricular Function, Left / Q000187:drug effects*
D047228:Angiotensin II Type 1 Receptor Blockers; D000959:Antihypertensive Agents; D001562:Benzimidazoles; D001713:Biphenyl Compounds; D013777:Tetrazoles; D020097:Natriuretic Peptide, Brain; D019797:3-Iodobenzylguanidine; C081643:candesartan