CARDIOVASCULAR MODULE: CARDIAC VALVULAR DISORDERS Adult Medical-Surgical Nursing.
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CARDIOVASCULAR MODULE: CARDIAC VALVULAR DISORDERS
Adult Medical-Surgical Nursing
Cardiac Valvular Disorders: Description
The cardiac valves are: AorticPulmonary MitralTricuspidDisorders lead to poor blood flow through the
heart, and may lead to ↓ cardiac output
Cardiac Valvular Disorders: Classification
Stenosis
Incompetence
Cardiac Valve Stenosis
Narrowing of the valve
Increases demand on the myocardium to pump blood through the valve
Cardiac Valve Incompetence
Incompetence/ regurgitation: A damaged valve which leaks and does not
close properly
Leads to:Backflow of blood during systole and
increased back pressure↓ cardiac output
Cardiac Valvular Disorder: Aetiology
CongenitalAgeing: wear and tear Rheumatic heart disease or bacterial
endocarditis:An auto-immune response following
Rheumatic fever (less common now) or streptococcal throat infection
→ endocarditis and chronic bacterial vegetation around valve/ valves
Cardiac Valvular Disorder: Diagnosis
History and clinical findingsChest XrayECGEchocardiographyCardiac catheterisation: reveals degree of
closure / incompetence
Prevalent Conditions
Mitral stenosis
Mitral incompetence
Aortic stenosis
Aortic incompetence
Mitral Stenosis
Mitral Stenosis: Pathophysiology
Narrowing of mitral valve:This causes left atrium to force blood to left
ventricle → dilatation/ hypertrophy of left atriumAtrial fibrillation: risk of thrombus/ emboli
Backflow/ congestion in pulmonary circulation leads to:
Increased workload of right ventricle →Right heart failure
Mitral Stenosis: Clinical Manifestations
Fatigue/ dizziness (low cardiac output)Respiratory problems: Dyspnoea, cough, frequent chest infections,
haemoptysisAtrial fibrillation (dysrythmia): weak often
irregular pulse (risk of emboli)
Diastolic murmur on auscultation
Mitral Stenosis: Medical Management
Treat congestive heart failure:Diuretics, Digoxin, vasodilators (reduce
afterload)Anti-dysrythmicsAnticoagulants (longterm to prevent emboli)Antibiotics prior to dental or surgical
procedures (to prevent endocarditis)
Mitral Stenosis: Surgery
Valvotomy
Valve replacement:An animal or human valveAn artificial valve (prosthesis)**With an artificial valve long-term
anticoagulants required (risk of thrombus)
Mitral Incompetence
Mitral Incompetence: Pathophysiology
The mitral valve does not close and leaks causing:
Backflow of blood during systole from left ventricle to left atrium
→ cardiac output is reduced→ increased pressure, dilatation and
hypertrophy of left atriumPulmonary congestion → Right heart failure
Mitral Incompetence: Clinical Manifestations
Maybe symptomless
Fatigue and weaknessPalpitations on exertionDyspnoea and coughSystolic murmur at apex on auscultation
Mitral Incompetence: Surgery
Surgical intervention is necessary as progressively cardiac output is reduced and pulmonary congestion increased:
Valvuloplasty (repair)Valve replacement
Medical management of symptoms
Aortic Stenosis
Aortic Stenosis: Pathophysiology
Narrowing of the aortic valve Causes increased filling and effort of the left
ventricle (forcing blood through) →
Left ventricular hypertrophy Left ventricular failure (maybe acute
pulmonary oedema)
Aortic Stenosis: Clinical Manifestations
Faintness/ dizziness (low cardiac output) Angina:O2 demand of hypertrophied left ventricleSlow forceful systole reduces diastole and
filling time for coronary circulationDyspnoea:If LVF: Copious blood-stained frothy sputum
Aortic Stenosis: Auscultation
Loud systolic murmur over aortic area and vibration of turbulent blood felt by a hand over the apex
Aortic Stenosis: Management
Medical:Treat angina and symptoms of LVF: Vasodilators, Digoxin, diuretics,
anticoagulantsAntibiotics prior to dental work or surgery to
prevent endocarditis
Surgery:ValvotomyValve replacement
Aortic Incompetence
Aortic Incompetence: Pathophysiology
Aortic valve is damaged and leakingBlood regurgitates from aorta during
diastole into left ventricle → dilatationLeft ventricle hypertrophies to force
emptying into the aorta → increased systolic BP Arterial vasodilatation to compensate (↓ peripheral resistance): ↓ diastolic BP(↑ pulse pressure) → LVF
Aortic Incompetence: Clinical
Manifestations
Forceful heartbeatDyspnoea on exertion and fatigueParoxysmal nocturnal dyspnoea and
orthopnoea (may lead to LVF)↑ pulse pressure, “water-hammer” pulse
(rapid strong pulse which then collapses)Diastolic murmur on auscultation
Aortic Incompetence: Management
Medical management of LVFAntibiotic cover for dental or surgery to
prevent endocarditis
Surgery: Aortic valve replacement(This is the preferred management)Anticoagulants long-term if artificial valve
Nursing Responsibilities
Physical examinationECG monitoringWeight, vital signs, fluid balanceICU nursing post-surgeryPatient education on diet, degree of exercise
and rest, medicationsPsychological/ emotional support
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