Exam 22 - Valvular Heart Disease

• Study guide for valvular heart disease

Definitions:

• Stenosis is the thickening of valve tissue, leading to narrowing
• Insufficiency (Regurgitation) is when the valve cannot close completely
• Valve replacement is replacing a stenosed or incompetent valve with a bioprosthetic or mechanical valve

Etiology/Pathophysiology:

• The Valves ensure directional blood flow through the heart
• Valves open and close passively in response to pressure changes
• Blood flows from the body via the vena cava to the right atrium, through the tricuspid valve to the right ventricle, through the pulmonary valve to the pulmonary artery and lungs
• Blood returns to the left atrium, goes through the mitral valve to the left ventricle, and out the aorta to the body
• Valvular heart disease occurs when valves are damaged, and can be congenital in children, adolescents, and adults
• Rheumatic fever can be a prominent factor, with symptoms appearing 10-40 years after rheumatic fever
• The left side of the heart (mitral and aortic valves) is more affected due to higher blood volume and workload

Types of Valvular Heart Disorders:

• Mitral stenosis and insufficiency is often caused by rheumatic fever
• Mitral prolapse is the weakening of valve leaflets and cords, causing prolapse into the left atrium
• Aortic stenosis (AS) is commonly due to atherosclerosis
• Aortic insufficiency (AI) can result from infective endocarditis or hypertension
• Tricuspid stenosis is rare, but linked to IV drug use and rheumatic fever
• Pulmonary stenosis is congenital

Clinical Manifestations

• Clinical manifestations depend on the specific disease
• Clinical manifestations are related to decreased cardiac output and the severity of heart failure

Assessment:

• Subjective data includes what the patient reports
• History of rheumatic heart fever
• Inability to perform ADLs without fatigue or shortness of breath
• Chest pain: Quality, onset, duration, precipitating and alleviating factors
• Lightheadedness, dizziness, or fainting
• Dyspnea, exertional dyspnea, and nocturnal dyspnea (s/s of heart failure).
• Objective data is what is observed of:
• Murmurs: Note character and location to identify the affected valve
• Breath sounds: Crackles, wheezing
• Edema: Pitting or non-pitting

Diagnostic Tests:

• Chest radiograph: Looking for calcification
• Echocardiogram: Detects valvular regurgitation
• Cardiac catheterization: Confirms valvular disease

Medical Management:

• Activity limitations
• Sodium-restricted diet

Medications:

• Diuretics reduce volume overload
• Cardiac glycosides control atrial fibrillation
• Antidysrhythmics manage arrhythmias
• Anticoagulants (e.g., Warfarin) following valve surgery
• Antibiotics are a prophylaxis for infective endocarditis

Surgical Intervention:

• Surgical intervention is indicated when medical therapy is no longer effective or there is evidence of progressive myocardial failure
• Valve repair is an open commissurotomy (surgical splitting of the fused mitral valve) for mitral valve stenosis
• Valve replacement uses prosthetic or mechanical valves
• Includes porcine, heterograft (tissue from one species to another), homograft (tissue from same species), and ball in cage valves

Care for Patient with Valvular Heart Disease includes focus on decreased cardiac output:

• Activity intolerance: Balance rest with activity, get assistance as needed, use prescribed oxygen
• Symptom relief and promoting comfort: Administer medications like Digoxin, diuretics, antidysrhythmics, and oxygen
• Fluid volume excess: Assess respiratory and cardiovascular systems, check for edema and capillary refill, monitor I&O, weigh daily, maintain sodium-restricted diet

Patient Teaching:

• Medications: Importance of antibiotics for preventing endocarditis, anticoagulant therapy after valve surgery, and taking medications as prescribed
• Diet management: Salt-restricted diet
• Activity limitations: Balance rest and activity
• Diagnostic tests: Prothrombin time or INR monitoring for those on anticoagulants
• Disease process: Symptoms to report to the healthcare provider
• Prophylaxis: Notify all healthcare providers of valvular heart disease for prophylactic treatment before procedures; maintain good oral hygiene to prevent endocarditis