2.3 Heart Failure Flashcards
What is heart failure?
- impaired ability of ventricles to fill & pump blood effectively
- heart unable to meet metabolic demands of body
- end result of many conditions
Pulmonary edema?
abnormal accumulation of fluid in interstitial tissue & alveoli of lungs.
-may be caused by cardiac & NON cardiac disorders.
Neurohormone effects on the Cardio system
Aldosterone:
- causes Na and H2O retention
- induces vasoconstriction
- increases preload and afterload
Neurohormone effects on the Cardio system
Angiotensin II:
- increases preload and afterload
- increases hypertrophy of ventricular cells with prolonged secretion
- constricts the renal vasculature
- stimulates release of aldosterone, endothelin-1, and vasopressin. (potent vasoconstrictor)
Neurohormone effects on the Cardio system
BNP:
- causes vasodilation
- promotes diuresis and natriuresis (but not enough to counteract the effects of the other hormones)
Neurohormone effects on the Cardio system
Endothelin-1:
-increases in angiotensin II and norepinephrine release
Neurohormone effects on the Cardio system
Epinephrine:
-causes vasoconstriction and increases afterload
Neurohormone effects on the Cardio system
Norepinephrine:
increases cardiac contractility
Neurohormone effects on the Cardio system
Renin:
-stimulates angiotensin II production
The heart is unable to contract forcefully enough in systole to eject adequate amounts of blood into the circulation; ejection fraction drops from 50-70% to less than 40%
What is Systolic Heart Failure
Ventricle is unable to relax adequately during diastole; ejection fraction may be normal
What is Diastolic Heart Failure
…….sounds diabolic….:)
Common causes of left-sided heart failure?
- coronary heart disease
- hypertension
Common causes of right-sided heart failure?
- conditions that restrict blood flow to the lungs
- COPD
The abrupt onset of myocardial injury, sudden decreased cardiac function…
Acute heart failure
Progressive deterioration of the heart muscle b/c of cardiomyopathies, valvular disease or coronary heart disease
Chronic heart failure
In cardiogenic pulmonary edema what is severely impaired?
The left ventricle
What is the leading cause of heart failure?
Coronary heart disease (ischemic heart disease)
Manifestations of left-sided failure?
- fatigue & activity intolerance
- syncope
- dyspnea
- SOB
- orthopnea (difficulty breathing when supine)
- cyanosis
Manifestations of right-sided failure?
- edema in feet & legs
- edema in sacrum if bedridden
- distended neck veins
- nausea & anorexia
Paroxysmal nocturnal dyspnea
waking at night acutely short of breath
Beta-Blockers
- inhibit SNS activity
- improve cardiac function
- reduce force of contraction (decreases workload)
Diuretics
- relieve symptoms related to fluid retention
- Loop diuretics often used - Lasix (furosemide)
Vasodilators
- relax smooth muscle
- reduces peripheral vascular resistance & afterload
- decreases myocardial work
- venous dilation reduces preload
Digitalis
Glycosides
- positive inotropic effect
- increase strength of contraction
- decreases SA node automaticity, slows conduction
- increases ventricular filling time.
