Characteristics of Heart Failure:
• Heart can’t pump enough blood to meet body’s metabolic needs
• Results in intravascular & interstitial volume overload & poor tissue perfusion
• Reduce exercise tolerance, reduced quality of life, & shortened life span
• Commonly caused by coronary artery disease
• Incidence of heart failure increase with age
• Prognosis depends on underlying cause & response to treatment
Causes:
• Atherosclerotic, rheumatic, congenital, or ischemic heart disease
• MI
• HTN
• Cardiomyopathy
• Valvular diseases
• Arrhythmias
• COPD
Pathophysiology
Left-sided Heart Failure
• Ineffective left ventricular contractile function
• Pumping ability of left ventricle fails, cardiac output falls
• Blood backs up into the left atrium & then into the lungs
Right- sided Heart failure
• Ineffective right ventricular contractile function
• Blood back ups into the right atrium & peripheral circulation
• Patient gains weight & develops peripheral edema
Systolic dysfunction
• Left ventricle can’t pump enough blood out to systemic circulation
• Blood backs up into pulmonary circulation & pressure ↑in pulmonary venous system
• Cardiac output falls; weakness & fatigue occur
Diastolic dysfunction
• Ability of LV to relax & fill during diastole is reduced & stroke volume falls
• Higher volumes needed in ventricles to maintain cardiac output