MITRAL STENOSIS

1. Definition - mitral valve thickens and gets narrower, blocking blood flow from the left atrium to left ventricle.
2. Physiology
• function of the heart is the transport of oxygen, carbon dioxide, nutrients and waste products
• cardiac cycle consists of:
• systole - the phase of contraction during which the chambers eject blood
• diastole - the phase of relaxation during which the chambers fill with blood. When heart pumps, myocardial layer contracts and relaxes.
1. blood flow:
• deoxygenated blood enters the right atrium through the superior and inferior vena cava
• enters the right ventricle via the tricuspid valve
• travels through the pulmonic valve to pulmonary arteries and lungs
• oxygenated blood returns from lungs through the pulmonary veins into left atrium and enters the left ventricle via bicuspid (mitral) valve.
• from the left ventricle, through the aortic valve through the aorta to the systemic circulation
• the heart itself is supplied with blood by the left and right coronary arteries
• the vascular system is a continuous network of blood vessels.
1. the arterial system consists of arteries, arterioles and capillaries and delivers oxygenated blood to tissues
2. oxygen, nutrients and metabolic waste are exchanged at the microscopic level
3. the venous system, veins and venules, returns the blood to the heart
3. Epidemiology
1. of clients with mitral stenosis, 2/3 are female
2. most cases of mitral stenosis are caused by rheumatic fever
4. Findings
• mild - no findings
• moderate to severe
1. dyspnea on exertion
2. paroxysmal nocturnal dyspnea
3. orthopnea
4. weakness, fatigue, and palpitations
• peripheral and facial cyanosis in severe cases
• jugular vein distention
• with severe pulmonary hypertension or tricuspid stenosis - ascites
• edema
• hepatomegaly
• diastolic thrill at the cardiac apex
• when client lies on left side, loud S1 or opening snap and a diastolic murmur at the apex
• crackles in lungs
5. Management
1. antiarrhythmics if needed
2. if medication fails, atrial fibrillation is treated with cardioversion.
3. low-sodium diet - to prevent fluid retention
4. oxygen if needed - to prevent hypoxia
5. surgery - mitral commissurotomy or valvotomy
6. Nursing interventions
1. the cardio-care six
2. observe closely for findings of heart failure, pulmonary edema, and reactions to drug therapy.
3. if client has had surgery, watch for hypotension, arrhythmias, and thrombus formation.
4. monitor the cardio seven
5. client and family
6. explain the need for long-term antibiotic therapy and the need for additional antibiotics before dental care.
7. report early findings of heart failure such as dyspnea or a hacking, nonproductive cough.
7. Diagnostic studies/findings
1. history and physical exam
2. EKG- for changes of left atrial enlargement and right ventricle enlargement
3. echocardiogram - for restricted movement of the mitral valves and diastolic turbulance