HEART FAILURE (HF)
Results when the myocardium cannot maintain the cardiac output that is required for normal metabolism and venous return
Fundamental abnormality impaired LV contractility => downward shift in the Frank Starling curve => any cardiac stress that increase venous return and cardiac pressures is not met by improved contractility and stroke volume =>decreased forward flow and increased backflow/congestion
Any Etiology -> LV dysfunction -> compensatory hormonal activation (Sympathetic system, Renin/Angiotensin/Aldosterone system) and release of vasodilatory peptides (Natriuretic peptides) -> failure of compensatory mechanisms -> end stage HF
Types of HF:
Systolic vs diastolic
Systolic = decreased Ejection fraction = less than 40% 50% incidence
Diastolic = impaired ventricular relaxation = decreased ventricular compliance 50%
* history and physical exam not useful in differentiating the two need ECHO *
Left vs right
Acute vs Chronic vs Terminal
a) Acute = Decompensated HF
Extremis = APE, Cardiogenic Shock (CS)
APE = congestion + hypertension
CS = congestion + hypotension + severe decrease in perfusion
Not in extremis = Worsening Baseline symptoms
b) Chronic: =Compensated HF
c) Terminal = End stage
Etiologies:
CAD, HTN most common causes
- Arrhythmias
- Myocardial diseases (infection/inflammation/infiltrative/cardiomyopathies)
- Others Beri-Beri, Thyroid, Pagets
Reasons for acute decompensation :
Myocardial ischemia/infarction
Uncontrolled HTN
Infection
Arrhythmia
Non-compliance
NSAIDS
Negative inotropic medications
ED management:
Hx kind of failure (old chart), reasons for decompensation,
P/E JVD, S3, murmurs
EKG
CxRay negative xray does not exclude HF; findings = dilated upper lobe vessels, enlarged PA, enlarged SVC, fluid pleural, interstitial, alveoli
Cardiac markers
*TIPS: ASYMPTOMATIC cardiac ischemia can precipitate HF newly or decompensate chronic ones
* TIPS: Xrays negative early on in HF, Pulmonary Contusion and Pneumonia
Beta Natriuretic Peptide (BNP) levels:
Vasodilator peptide from the ventricles in response to stretch of ventricles (failing heart)
Counter regulatory to SNS (sympathetic) and RAAAS (rennin/angio/aldosterone)
USES
increased with HF; useful for Dx = clinical + > 100pg/ml
related to prognosis lesser 6 month hospitalizations and 1 year deaths
correlates with PCWP and NYHA classifications of HF
Treatment:
a) APE = congestion + hypertension
Sit upright with LEGS DANGLING
100% O2
Diuretics -
IV Lasix
If never been on lasix : 40mg IV push
If been : double last 24 hour dose, if no effect in 20 minutes, double further ( Foleys needed !!)
If allergic to sulfa can only use Ethacrynic acid
* TIPS : Sulfa in Furosemide, Bumetanide, Torsemide and Acetazolamide
IV Morphine decreases anxiety, preload, pain, and adrenergic response in vascular beds
Nitrates - if SBP > 100
S/L nitro .4 mg q 1 min
IV nitro start 10 micrograms/min, increase by 5-10 mics/min, based on BP and symptoms
Nitroprusside if still high BP and symptoms,
ACE inhibitors s/l capoten, IV vasotec
Beta-Blockers 2 edged sword best avoided /left to the specialists and unit setting
When ACEI contraindicated choices are:
Digoxin, Spironolactone, combo of Hydralazine /Isosorbide Dinitrate
Non Invasive Ventilation use CPAP (BiPAP shows increased mortality !!
Inotropes: a bridge to definitive therapy
Dobutamine, Dopamine, Milrinone
Dobutamine for acute HF with SBP > 90
Dopamine for acute HF with SBP < 90
Milrinone for acute HF in cases of chronic HF ( down regulation of beta receptors)
b) Cardiogenic Shock = congestion + hypotension + decreased perfusion
* TIPS: 20/40/80 -
20 % incidence in MI
40% LV mass lost
80% mortality
Rx Inotropes, Balloon pump
New Stuff :
a) Nesiritide recombinant DNA form of BNP
mechanism of action vasodilator, decreased AL, PreL, Sodium and H2O loss, Anti- RAAS, SNS
uses in APE, CS
compared to dobutamine less arrhythmia risk, less death rates
b) DVT prophylaxis
HF predisposes to DVT !!
Use Enoxaprin 40 mg SC once a day decrease of DVT risk by 65%
* TIPS : careful with the use of diuretics and vasodilators in all the following scenarios:
- - Diastolic dysfunction
- - RV infarctions
- - LV outflow tract obstructions aortic stenosis , HCMP
