Transcript B-Type Natriuretic Peptide

B-Type Natriuretic Peptide
Julianna L. Murphy
Pharm.D. Candidate
Dr. Ali Rahimi, Preceptor
September 2, 2011
Natriuretic Peptides
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3 types in mammals
Atrial natriuretic peptide (ANP)
 B-type natriuretic peptide (BNP)
 C-type natriuretic peptide (CNP)
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Regulate blood volume/pressure
 Inhibit cardiac hypertrophy
 Stimulate long bone growth
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B-type Natriuretic Peptide
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Primarily synthesized in the heart
Released by ventricles in response to excessive
stretching of cardiac muscle cells
Co-secreted with NT-proBNP
Synthesis of BNP
Action at Target Cells
© 2004 European Society of Cardiology
Effects of BNP
Effects of BNP

Reduces sodium
reabsorption
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Increases sodium
excretion
Other Effects of BNP
Central and peripheral sympathoinhibitory
effects
 Activation threshold of vagal afferents is
lowered
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suppresses the reflex tachycardia
 Suppresses reflex vasoconstriction
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BNP Clearance
Lysosomal degradation via NPR-C
receptor
 Enzymatic degradation via neutral
endopeptidase
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BNP Pharmacotherapy:
Nesiritide (Natrecor)
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Human BNP (hBNP)
Manufactured in E. coli using recombinant DNA
technology
Indicated to treat acutely decompensated congestive
heart failure, with dyspnea at rest or minimal activity.
Nesiritide Study
Impact of Early Initiation of
Intravenous Therapy for Acute
Decompensated Heart Failure
on Outcomes in ADHERE
Peacock, W., et al. Cardiology. (2007)107(1):44-51.
Purpose
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To determine the impact of early ED initiation of acute
decompensated heart failure (ADHF)-specific therapy,
as indicated by nesiritide use, on subsequent outcomes
Patient Population
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Identified patients with initial systolic blood
pressure > 90 mmHg and negative cardiac
biomarkers
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hospitalized after presentation to the ED
received nesiritide but no other intravenous vasoactive
drugs
Admissions for heart failure between October
2001 and January 2004
> 270 participating hospitals
Inclusion/Exclusion Criteria
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Inclusions:
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Emergency Department (ED) was a patient’s initial point of
care before admission
Received nesiritide at any point during hospitalization
Nesiritide sole vasoactive drug therapy
Exclusions:
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Initial abnormal elevation in markers of myocardial injury
Systolic blood pressure < 90 mmHg
Group Differentiation
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Patients who first received nesiritide in ED
labeled as ‘EDN’
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1,613 patients
Patients who first received nesiritide in an
inpatient unit labeled as ‘INN’
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2,687 patients
Outcome Measures
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Total length of stay in hospital (LOS)
Prolonged hospital LOS
Transfer to intensive care unit (ICU)
Total ICU LOS
Asymptomatic status at discharge
Discharged to home
In-hospital mortality
Results
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Compared to the INN group, EDN patients:
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Had a shorter adjusted mean total hospital LOS (5.2
vs. 6.9 days; p< 0.001)
Less likely to require transfer to ICU from another
inpatient unit (OR: 0.301; 95% CI: 0.206–0.440)
More likely to be discharged home (OR: 1.154; 95%
CI: 1.005–1.325)
Results
Results
Results
Results
Results
Limitations
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Variations in patient management among participating
institutions
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Time to treatment with nesiritide varied in both groups
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Study not randomized, controlled, or blinded
Authors’ Conclusions
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The data suggests that a strategy of early initiation of
ADHF-specific therapy in the ED is associated with
shorter and improved overall course of hospitalization.
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More studies are needed to study the benefits and any
risks of initiating nesiritide therapy earlier in the course
of treatment for ADHF.
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Level of Evidence: IIb
References
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‘Biological variation of the natriuretic peptides and their role in monitoring patients
with heart failure.” Wu, A; et al. European Journal of Heart
Failure. (2004) 6 (3): 355-358.
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“Brain and Other Natriuretic Peptides: Molecular Aspects.” Vanderhayden, Marc, et
al. European Journal of Heart Failure. 2004, 3: 261-268.
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“Coronary vasodilator effects of BNP: mechanisms of action in coronary
conductance and resistance arteries.” Zellner, C; et al. The American Journal of
Physiology. 1999 Mar;276(3 Pt 2):H1049-57
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“Impact of Early Initiation of Intravenous Therapy for Acute Decompensated Heart
Failure on Outcomes in ADHERE.” Peacock, W.; et al. Cardiology.
(2007)107(1):44-51.
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“Natriuretic Peptides.” Basic and Clinical Pharmacology. 11th edition. Katzung, B.,
ed.