How myocardial damage leads to heart failure:
Left-sided Heart Failure
• Increased workload & end diastolic volume enlarge the LV
• Diminished function allows blood to pool in the ventricle & atrium back up into the pulmonary veins & capillaries
• Rising capillary pressure pushes sodium & water into interstitial space
• Fluid in the extremities moves into the systemic circulation
• RV becomes stressed because it’s pumping against a greater pulmonary vascular resistance & LV pressure
Right-sided Heart Failure
• Stressed right ventricle enlarges with the formation of stretched tissue
• Blood pools in the right ventricle & right atrium
• Backed-up blood also distends the visceral veins
• Rising capillary pressure forces excess fluid from the capillaries into the interstitial space
Key Signs & Symptoms
Left-sided Heart Failure
• Dyspnea
• Orthopnea
• Paroxysmal nocturnal dysnea
• Reduced sympathetic stimulation while sleeping
• Pulmonary congestion
• Tachycardia
• S3
• S4
• Cool, pale skin
• Restlessness
Right-sided Heart Failure
• Jugular vein distention
• Positive hepatojugular reflux
• Hepatomegaly
Complications
• Pulmonary edema
• Acute renal failure
• Arrhythmias
• Activity intolerance
• Renal impairment
• Cardiac cachexia
Diagnosis
• Increased pulmonary vascular markings
• Interstitial edema
• Pleural effusion
• Tachycardia
• Extrasystoles
• Abnormal liver function tests
• Elevated BUN& creatinine
• Prothrombin time maybe prolonged
• Elevated pulmonary artery & pulmonary wedge pressures
• Radionuclide ventriculography, diastolic dysfunction, ejection fraction may be normal
Treatment
• Diuretics
• ACE inhibitors
• Vasodilators
• Digoxin
• Beta-adrenergic blockers
• Sodium-restricted diet
• Antiembolism stockings
• Surgical valve replacement
• Coronary artery bypass grafting
• PTCA
• Stenting
• Mechanical VAD