Kamis, 17 April 2014

Heart Failure

Prevalence
Affects nearly 5 million Americans currently, >500,000 new cases diagnosed each year
Cost
Annual direct cost in >10 billion dollars
Incidence increased with age
Effects 1-2% of patient from 50-59-years-old and 10% of patient over the age of 75
Frequency
It is the most common inpatient diagnosis in the US for patients over 65 years of age
Visits to their family practitioner on average 2-3 times per year
Gender
Men> women in those between 40 and 75 years of age
The sexes are equal over 75 years of age  



Systolic Dysfunction (Decreased Contractility)
Reduction in muscle mass (e.g., myocardial infarction)
Dilated cardiomyopathies
Ventricular hypertrophy
Pressure overload (e.g., systemic or pulmonary hypertension,
aortic or pulmonic valve stenosis)
Volume overload (e.g., valvular regurgitation, shunts, high-output states)
 
Diastolic Dysfunction (Restriction in Ventricular Filling)
Increased ventricular stiffness
Ventricular hypertrophy (e.g., hypertrophic cardiomyopathy,
other examples above)
Infiltrative myocardial diseases (e.g., amyloidosis, sarcoidosis,
endomyocardial fibrosis)
Myocardial ischemia and infarction
Mitral or tricuspid valve stenosis
Pericardial disease (e.g., pericarditis, pericardial tamponade)
 
Pathophysiology of Heart Failure
Hemodynamic Model
Neurohumoral Adaptations
“double-edged swords”
Renin-Angiotensin-Aldosterone System
Sympathetic Nervous System
Antidiuretic Hormone
Atrial and B-type Natriuretic Peptides
Endothelin
 
 
 
Clinical Presentation 
Asymtomatic to cardiogenic shock
Primary symptoms :
Dyspnea (particularly on excertion)
fatique
Exercise intolerance
Pulmonary symptoms :
Orthopnea
Paroxysmal nocturnal dyspnea
Tachypnea
Cough
Fluid overload