Cardiothoracic Surgery Dr.Mohammed J. Jameel FIBMS.Th.CVS.Senior Lecturer. Department of Surgery, College of Medicine, Al-Mustansiriyah University, Baghdad, Iarq.

Mitral Valve Disease: 1. Mitral stenosis: Lec : 2 Mitral Valve Disease: 1. Mitral stenosis: Etiology:- 1.Rheumatic heart disease. 2. Calcific degeneration. 3. Cardiac Tumor like left atrial myxoma 4. Congenital mitral stenosis Pathophsiology:- The development of mitral stenosis is usually progressive in which the normal surface area of valve decrease from 4-6 cm2 to about 1-1.5 cm2 at this stage it is called Moderate mitral stenosis and patient become symptomatic . When valve surface area decrease to 0.8 cm2 the condition called Severe mitral stenosis.

Pathophsiology Mitral stenosis lead to increase in the left atrial pressure leading to pulmonary venous congestion and pulmonary hypertension this produce left atrial dilatation and atrial fibrillation this will decrease the volume of blood which pass from the left atrium to left ventricle which depend mainly on the left atrial contraction therefore left ventricle end diastolic volume decrease and stroke volume and cardiac output decrease also.   Clinical Features:- 1. Exertional dyspnea 2. Decrease exercise capacity 3. Orthopnea 4. Paroxysmal nocturnal dyspnea 5. Pulmonary oedema 6. Atrial fibrillation 7. Embolic episode Auscultation: 1.Loud first heart sound. 2. Diastolic murmur at cardiac apex.

Diagnosis: by echo which shows: 1. Valve surface area 2. Transvalvular pressure gradient. 3. Asses leaflet mobility, calcification and subvalvular fusion. Management:- 1.Mitral valve repair: two methods Percutaneous balloon valvoplasty Open mitral commissurutomy: it allows mobilization of fused papillary muscles and removal of left atrial clot. It can be done for patient with moderate mitral stenosis with non calcified valve.

2. Mitral valve replacement: TYPES of available valve A. Mechanical bileaflet valve: This require life- long anticoagulation with warfarin, suitable for young patient with long life expectancy, require careful INR monitor which must be kept between 2-3 B. Tissue valve (either bovine or porcine): 1. does not require warfarin therapy. 2. suitable for old patient and young female who desire to be pregnant. 3. Durability is between 5-10 years, sometimes re- operation may be needed.

2. Mitral valve insufficiency: Etiology:- 1. Degenerative disease 50-60 % 2. Rheumatic fever 15-20 % 3. Ischemic disease 15-20 % 4. Endocarditis 5. Congenital abnormalities 6. Cardiomyopathy Pathology: The mitral valve composed of:- 1. Annulus. 2. Leaflets. 3.Chordae. 4. Papillay muscles. A defect in any one of these components may create mitral insufficiency.

Pathophysiology: The regurgitation of part of left ventricle stroke volume to left atrium will decrease forward blood flow and increase left atrial pressure leading to pulmonary congestion and volume over load on left ventricle, this will lead to dilatation of both left atrium and left ventricle. Clinical features: In acute Mitral Regurgitation symptoms of congestive heart failure may develop suddenly. In chronic cases patient complains from exertional dyspnea, decrease exercise capacity which progress to pulmonary congestion and left ventricle dysfunction. On auscultation apical pansystolic murmur radiate to axilla.

Diagnosis: by echo which shows 1. Site of pathology in the valve. 2. Size of cardiac chambers. 3. The volume of forward cardiac output. Indications for surgery: 1. Symptomatic patient. 2. Recent onset of atrial fibrillation. 3. Asymptomatic patient with ejection fraction less than 50%( severe mitral insufficiency

Operative Methods:  1. Mitral valve replacement when the valve is severely damaged. 2. Mitral valve repair when there is minimum damage to valve element, this can be done by one or combination of the following procedures. Commissurotomy to free fused leaflets from each other. Annuloplasty to correct the size of dilated annulus. Suturing of perforated leaflets. Repair of damaged chordae or rupture papillary muscle.  

Aortic valve disease: 1. Aortic stenosis: Etiology:- 1.Congenital 30 % (bicuspid valve). 2. Rheumatic disease 10-15 %. 3. Calcific valve stenosis 60 % (degenerative disease). Pathophsiology:-Aortic stenosis leads to reduction in the ejection fraction and increase transvalvular pressure gradient and increase myocardial work load producing left ventricle hypertrophy. Normal aortic valve has cross sectional area 2.5-3.5cm2 Moderate aortic stenosis 1.2-1 cm2 Severe aortic stenosis 0.8 cm2 or less Clinical features:- 1. Decrease exercise capacity. 2. Heart failure. 3. Angina. 4. Syncope.

Diagnosis: - By Echo which shows : measure transvalvular pressure gradient. Calculate valve surface area. Measure blood flow velocity across the valve. Show the degree of leaflet immobility and left ventricle hypertrophy. Indication for surgery: 1. Symptomatic patient. 2. Asymptomatic patient with moderate to severe aortic stenosis Operative methods: Aortic valve replacement by either: Mechanical valve which requires lifelong warfarin. Autograft valve in which pulmonary valve is harvested and implanted instead of aortic valve together with coronary artery re-implantation and homograft tissue valve is put in the pulmonary area (Ross procedure).

2. Aortic Regurgitation:- Etiology:- 1. Degenerative diseases. 2. Endocarditis. 3. Rheumatic heart diseases 4. Conginital. 5. Aortic root dilatation. Pathophiology: - Blood will return from aorta to left ventricle during diastolic phase producing left ventricular volume overload and dilatation Clinical features:- 1. Dyspnea on exertion. 2. Palpitation. 3. Wide pulse pressure 4. Angina due to decrease diastolic pressure which reduce coronary perfusion 5. Diastolic murmur in left third intercostal space when patient lean forwards.

Indications for surgery:- Diagnosis:- By echo: 1.Measures the degree of valvular insufficiency. 2. Measures left ventricle size. Indications for surgery:- Symptomatic patient. Asymptomatic patient with severe Aortic insufficiency. Aortic valve is replaced with mechanical valve with lifelong warfarin therapy.