Acute HF Flashcards
Epidemiology of Acute HF (8)
Approximately ¾ of patients present to ED
Average age is 72.4 years
Over 1 million hospitalizations each year
75% due to insult in exisiting HF patient
25% de novo HF
5% due to disease progression
Average length of stay is 4 - 5 days
Rehospitalization occurs in 50% of patients!
Cardiac Index (CI)
CI = CO/m2
CI is expressed at L/min/m2
Normal range 2.5-4 L/min/m2
Utility: determinant of O2 delivery and perfusion
You would predict that CI is __low____ in patient with ADHF
Cardiac Output
volume of blood ejected from left ventricle during systole (L/min)
Pulmonary capillary wedge pressure (PCWP)
pulmonary artery occlusion pressure (PAOP)
Normal range 8-12 mmHg
Indirectly measures end diastolic volume
Utility: determinant of patient’s preload / volume status
You would predict that PCWP is __high__in patient with ADHF
Arginine Vasopressin (AVP)
Hormone secreted by posterior pituitary to maintain water homeostasis Also known as antidiuretic hormore Actions Inhibits renal excretion of free water Potent vasoconstriction
Elevated AVP levels in heart failure
Diagnostic value of BNP
100-500 pg/ml has a high sensitivity towards “cardiac issues”
A clinician will use this to differentiate between cardiac and non-cardiac causes of pulmonary congestion/edema
Also, in a patient with a baseline of BNP, any sharp increase is an indicator of a worsening of their HF
Acute decompensated heart failure
There has been an insult/problem to the body (NSAIDS, cocaine, trauma, excess salt) where there is not enough blood being distributed through the body
- Cyanotic, fluid edema, pulm edema
3 ADHF compensatory mechanisms
ET-1
AVP
BNP/ANP
Endothelin-1 (ET-1)
Actions Potent vasoconstriction Induces cardiac remodeling Decreases renal blood flow (GFR) Also acts to further stimulate the RAAS and SNS systems
Elevated ET-1 levels in heart failure and other diseases
Atrial Natriuretic Peptide (ANP)
B-type Natriuretic Peptide (BNP)
ANP is released from atrial myocardium in response to atrial dilation and stretch
BNP is released from ventricular myocardium in response to elevated end diastolic volume (preload)
Both ANP and BNP are elevated in ADHF patients
Actions: vasodilation, natriuresis, diuresis
BNP “helps us”; it balances ET-1 and AVP
Used as a diagnostic tool, very valuable from differentiating between ADHF and PNA
Two main reasons how ADHF occurs
Decreased CO/CI
Sodium/H2O retention
Neurohormonal Actions of ANP and BNP
Antagonizes RAAS
Inhibits SNS
Antagonizes ET-1
Results in peripheral and coronary vasodilation
Renal Actions of ANP and BNP
increases GFR
diuresis
natriuresis
Non-drug related precipitating factors for ADHF
Ischemia Arrhythmias Uncontrolled HTN Dietary indiscretion (high Na diets) Pulmonary embolism Valvular dysfunction Disease progression Thyroid disorders Electrolyte abnormalities Anemia Infection Worsening renal function Non compliance
Drugs that cause water and Na retention (4)
Corticosteroids
NSAIDs (ibuprofen, naproxen)
Thiazolidinediones (pioglitazone, rosiglitazone)
Some antibiotics
Drugs that decrease cardiac contractility
Alcohol Beta blockers Non-dihydropyridine CCB Some antiarrhythmics Some chemotherapy agents (doxorubicin)
ADHERE registry
Factors for in-hospital mortality include
BUN ≥ 43 mg/dL
SBP < 115 mmHg
SCr ≥ 2.75 mg/dL
Mortality is 20%