Valvular heart disease

Question 1

2 Atrioventricular Valves

Answer 1

Valves that connect the atria to the ventricles
Mitral valve - connects the left atrium to the left ventricle
Tricuspid valve - connects the right atrium and right ventricle

Question 2

2 semilunar valves

Answer 2

Semilunar valves are the valves connecting the ventricles to the great vessels
Aortic - connects the left ventricle to the aorta
Pulmonic - connects the right ventricle to the pulmonary artery

Question 3

Valvular heart disease is defined according to:

Answer 3

1. valve (s)
2. functional alteration:
   a) stenosis
   b) regurgitation

Question 4

Stenosis

Answer 4

• Valve orifice restricted
• Forward blood flow impeded
• Pressure gradient across open valve - increases because of the increased resistance to flow.

Question 5

Regurgitation

Answer 5

• (aka) valvular incompetence or insufficiency
• incomplete closure of valve leaflets
• results in backward flow of blood

Question 6

Mitral Stenosis: what causes it?

Answer 6

most cases are from rheumatic heart disease
rheumatic mitral stenosis is most prevalent in developing countries

Question 7

What is mitral stenosis and how does it effect pressure gradient in the heart

Answer 7

Contractures & adhesions between commissures - > structural deformities -> obstruction of blood flow -> results in pressure difference between LA & LV
increased pressure and volume in LA and increased pulmonary vascular pressure - pulmonary hypertension

Question 7

How does rheumatic endocarditis effect the valves

Answer 7

causes scarring of valve leaflets & cordae tendineae

Question 7

Clinical Manifestations of mitral regurgitation
Acute and Chronic

Answer 7

Acute: thready pulses, cool, clammy extremities
Chronic: may be asymptomatic for years, symptoms of LV HF

Question 7

Clinical Manifestations of Mitral Stenosis (5)

Answer 7

• Exertional dypsnea (d/t decreased lung compliance)
• Atrial fibrillation (fatigue, palpitation)
• hemoptysis (pulmonary hypertension)

Question 7

Symptoms of LV HF

Answer 7

weakness, fatigue, d/t decreased CO, dyspnea gradually progressing to orthopnea, nocturnal dyspnea, respiratory distress that awakens the patient, exertional dyspnea

Question 8

Mitral Valve Regurgitation

Answer 8

Incomplete mitral valve closure
Blood flows backward from LV to LA during systole
LA and LV have to work harder to generate adequate CO
Eventual enlargement of LA, ventricular hypertrophy and dilation

Question 9

Mitral Valve Regurgitation is related to defect from: (5)

Answer 9

Mitral leaflet
Mitral annulus
Chordae tendineae
Papillary muscles
LA & LV

Question 10

Most cases of Mitral Valve Regurgitation are caused by: (5)

Answer 10

MI, chronic rheumatic heart disease, mitral valve prolapse, ischemia of papillary muscles, or infective carditis

Question 11

Aortic Stenosis

Answer 11

causes a thickening and narrowing of the valve between the LV and aorta. narrowing creates a smaller opening for blood to flow through. blood flow from the heart to the rest of the body is reduced or blocked
Causes obstruction of blood flow from LV to aorta during systole -> LV hypertrophy and increased myocardial O2 consumption

Question 11

Congenital aortic stenosis

Answer 11

usually discovered in childhood, adolescence, or young adulthood

Question 12

Aortic Stenosis In older adults

Answer 12

result of rheumatic fever or degeneration

Question 13

In rheumatic fever

Answer 13

fusion of commissures and secondary calcification - causes valve leaflets to stiffen and retract -> results in stenosis

Question 14

IF AS is from rheumatic fever what accompanies it?

Answer 14

mitral valve disease

Question 15

Aortic Valve Regurgitation

Answer 15

May be result of primary disease of aortic valve leaflets or aortic root
Backward blood flow from aorta - into left V, when aortic v should be closed which results in volume overload

Question 16

Causes of Acute AR (3)

Answer 16

from infective endocarditis, trauma, aortic dissection

Question 17

causes of chronic AR

Answer 17

generally results of rheumatic heart disease, a congenital bicuspid aortic valve, syphilis

Question 18

Clinical manifestations of Aortic Valve Stenosis: Classic triad and how much does it have to be stenosed to get these?

Answer 18

Symptoms develop when valve orifice decreases to 1/3 of its normal size
1. Angina
2. Syncope
3. Exertional dyspnea

Question 19

Should nitro be given in aortic valve stenosis?

Answer 19

Use of nitro is not recommended because it reduces preload (by vasodilating veins) and preload is necessary to open the stiffened aortic valve and can cause significant decrease in BP.
- preload is the amount of stretch your heart has when it is most full right before it empties.

Question 20

Clinical manifestations of Aortic valve regurgitation: acute

Answer 20

sudden manifestation of severe dyspnea, chest pain, progression to shock

Question 21

Clinical manifestations of Aortic valve regurgitation: Chronic

Answer 21

Exertional dyspnea, fatigue, orthopnea, paroxysmal nocturnal dyspnea
Water hammer pulse - a strong quick beat that collapses immediately
Generally asymptomatic for years, then presents with symptoms after myocardial dysfunction has occured

Question 22

Conservative management of Valvular Heart Disease

Answer 22

Prevention of recurrent rheumatic fever and infective endocarditis
Depends on the valve involved and severity of disease
Preventing exacerbation of HF, acute pulmonary edema, thrombo-embolism, and recurrent IE
If signs of heart failure
- vasodilators, positive inotropes, beta-blockers, low sodium diet, diuretics

Question 23

Percutaneous Aortic Valve Replacement

Answer 23

For people who are at high risk for surgical treatment
Replacement via femoral artery, performed in catheterization lab

Question 24

Percutaneous Transluminal Balloon Valvuloplasty

Answer 24

Splits open fused commissures
Used for mitral tricuspid and pulmonic. less often for aortic

Question 25

Are valve surgeries curative?

Answer 25

Surgical all-types of valve surgery are palliative not curative and the patient will require life-long health care.

Question 26

Mechanical prosthetic valves

Answer 26

More durable and lasts longer
Increased risk of thrombo-embolism, require long-term anticoagulation therapy

Question 27

Biological prosthetic valves

Answer 27

Bovine, porcine, and human cardiac tissue
Does not require anticoagulant therapy
Less durable

Question 28

Diagnosis for valvular heart disease

Answer 28

Based on
History
Physical Exam
Echo - shows valve structure, function & chamber size
Cardiac Catheterization (esp surgical option)
- reveals pressure changes in cardiac chambers, measures pressure gradients across valves and quantifies the size of valve openings

Question 29

Post-op Nursing Care: ICU (8)

Answer 29

hemodynamic monitoring - continuous VS, q15 min initially. 12-lead ECG
resp: ventilated, routine ABG, respiratory therapists role
CXR
Pain control (IV morphine, PO T3
Accurate I&O (manage blood loss, chest tube output q1h, U/O, CVP q1h
N/G to intermittent low wall suction
Wound: sternal incision
Mobility - post-extubation/PT

Question 30

Post-op Nursing Care: Stepdown Unit (8)

Answer 30

• H2T physical assessment
• Pain control (PO T3)
• Titrate O2 to maintain SpO2 > 95%
• D/C CVP lines, chest tubes, Foley cath
• Dangle (sit up) on the edge of bed; may sit up in chair
• Electrolyte replacement (may use diuretics)
• Resume cariac meds and pre-op meds & subcut heparin
• DB &C q1h while awake & mobilize