Controversy and Conflict in the Treatment of Acute Decompensated Heart Failure: Nesiritide as Evidence-Based Treatment

Inotropic therapy: an important role in the treatment of advanced symptomatic heart failure

Inotropic therapy remains an option in the management of patients with advanced heart failure symptoms from systolic dysfunction who do not respond to conventional therapies. The decision to use this class is largely predicated on an accurate evaluation of the patient's fluid and perfusion status. Selection of the appropriate agent and dosing regimens requires an understanding of the underlying pathophysiology of heart failure and concomitant therapy. Most important, the goals of care should be stated clearly, given inherent risks associated with this class of drug.

Risk and safety assessment of exogenous human brain natriuretic peptide in cynomolgus monkeys (Macaca fascicularis)--a subchronic study

Safety evaluation of synthetic human brain natriuretic peptide (shBNP) was carried out in cynomolgus monkeys (Macaca fascicularis) by 2-week intravenous toxicity studies. System exposure was also assessed throughout the whole administration. Three test groups received doses of 432, 1440 and 4320 microg/kg/day of shBNP, with a high infusion rate of 36 mL/kg/hr for 30 min compared to the clinical protocol of continuous infusion over 24h. Commercially available recombinant human brain natriuretic peptide (rhBNP) of 1440 microg/kg/day was used as positive control. The 2-week repeated intravenous doses of shBNP resulted in reversible increased serum LDH and CPK in monkeys receiving 1440 and 4320 microg/kg/day dose with no pertinent histopathological changes. Some changes related to the pharmacologic effects of BNP including hypotension was observed after administration. No treatment-related mortalities or renal dysfunction were found. Controversy about the safety issue of BNP as an exogenous hormone concerning ventricular remodeling and myocardial cell apoptosis, coupled with our results, were also discussed. The no-observed-adverse-effect level (NOAEL) was considered to be 432 microg/kg /day, which is about 20 times higher than the commonly used clinical dose. The results of the present study advocate the safety of shBNP in cynomolgus monkeys at levels used in the study.

B type natriuretic peptide--a diagnostic breakthrough in peri-operative cardiac risk assessment?

The B-type natriuretic peptides; B-type natriuretic peptide and N-terminal pro-B-type natriuretic peptide, are increasing being used as biomarkers for the diagnosis, management and prognostication of cardiac failure, but their application in the peri-operative period is unclear. This review examines the current understanding of the role of B-type natriuretic peptides in both the operative and non-operative settings. Normal values, diagnostic thresholds, monitoring targets and significant prognostic levels are identified. Using this as a background, the role of B-type natriuretic peptides in the prediction of peri-operative mortality and morbidity is examined and potential confounders, such as renal failure and body mass index, which may impact significantly on the utility of the biomarkers, are discussed. Clinical recommendations with regard to its use are made and a research agenda is proposed for future peri-operative studies.