1. Valvular Heart Disease: The Mitral Valve

2. Case
A 45 year old man presents to establish care. He was told many years ago that he needed antibiotics prior to dental work because there was a problem with a heart valve. He has occasional palpitations. On exam he has brisk carotid upstrokes and a holosystolic murmur is heard best at the apex along with an S3 and a diastolic rumble.

3. Case What is the next best step? Do nothing, this murmur is benign
Do an exercise stress test because the patient may have CAD and ischemic heart disease
Do nothing, exam findings suggest mild disease
Order an echocardiogram
Refer the patient to a cardiologist for further evaluation

4. Case
An echocardiogram shows moderately dilated left atrium, a normal appearing left ventricle with am EF of 55%, a prolapsing posterior mitral leaflet and severe MR. Now you should:
Tell the patient to continue antibiotic prophylaxis prior to the dental work
Have the patient follow up with a annual echo
Refer the patient for valve surgery
Refer the patient for a defibrilator to prevent sudden death from MVP

5. What Makes A Heart Murmur?
High blood flow through a normal or abnormal orifice
Forward flow through a narrowed or irregular orifice
Backward flow through an incompetent valve

6. These Murmurs Are Benign
Mid systolic murmur at the left sternal border with grade 2 or less with a normal S1 and S2 and no other abnormal findings in an otherwise asymptomatic patient
Associated with normal or increased blood flow across normal valves

7. These Murmurs Need Further Evaluation
Diastolic Murmurs
Continuous Murmurs
Systolic
Loud
Early systolic
Late systolic
Holosystolic

8. Strategy For The Evaluation Of Cardiac Murmurs
Bonow. JACC

9. When To Order An Echo Class I Class III
Diastolic, continuous, holosystolic, late systolic, clicks, radiation to neck or back
Symptoms of underlying cardio-pulmonary disease
Grade 3 or louder mid systolic murmurs
Class III
Mid systolic mumur grade II or less thought to be innocent

10. Mitral Valve Disease: From Many Structures
Mitral leaflets
Chordae
Papillary muscles
Mitral anulus
Otto. NEJM, 2001.

11. Etiology of Mitral Regurgitation
Organic (Primary pathology of the leaflets)
Degenerative
Rheumatic
Endocarditis
Congenital
Functional (Secondary to myocardial process)
Ischemic
Dilated cardiomyopathy
Hypertrophic cardiomyopathy

12. Enriquez-Serano. Contemporary Cardiology, 2009.

13. Mitral Regurgitation: Epidemiology
Prevalence: >5,000,000
Incidence: >650,000 new cases/year in the US
Most common discharge diagnosis
Most common cause of readmission < 60 days
Cost: > 34.8 billion annualy
FIGURE 25-1 Prevalence rates of heart failure by gender and age in the United States between 1988 and 1994—the Third National Health and Nutrition Examination Survey (NHANES III). Among men (blue), the prevalence increased from 18 cases per 1000 in those aged 45 to 54 years to 98 cases per 1000 in those aged 75 years and older. Among women (purple), the prevalence increased from 13 cases per 1000 in those aged 45 to 54 years to 97 cases per 1000 in those aged 75 years and older.  (Data from American Heart Association: Heart Disease and Stroke Statistics—2003 Update. Dallas, American Heart Association, 2002.)
Rosamond. Circulation, 2008.
Braunwald

14. Pathophysiology Volume overload ->
LV dilation
LA dilation
Acute: Rapidly increasing LA/PV pressures-> pulmonary edema
Chronic: Slow enlargement of the LA with low pressures
Left ventricular dilation and increased EF followed by LV deterioration
Foster. NEJM, 2002.

15. Hemodynamic Stages of Mitral Regurgitation
Libby. Braunwald’s Heart Disease. 8th Ed.

16. Natural History of Severe MR
Libby. Braunwald’s Heart Disease. 8th Ed.

17. Degenerative Mitral Valve Disease: Mitral Valve Prolapse
Most common organic mitral valve disease
Incidence about 2-3%
Usually results in mitral valve prolapse
Variable histology
Increased extracellular matrix
Thickened and redundant
Chordal elongation
Sanders. Forensic Science International, 2007.

18. Complications Chordal rupture and flail leaflet Heart failure
12% of patients
Most common in older men
Heart failure
Sudden death AF
Endocarditis
Most common compliation, but rare (100cases/100,000 patient years)
Higher risk with flail leaflet

19. Mitral Regurgitation: Mitral Valve Prolapse
Foster. NEJM

20. Echocardiogram: Flail Mitral Leaflet
Foster. NEJM

21. Endocarditis
Destruction of tissue by infection
About 5% of severe MR

22. Mitral Regurgitation From Connective Tissue Disease

23. Functional Mitral Regurgitation
Affects 15-20% with HF, 12% 30 days post MI
Leaflets are normal
Coaptation is incomplete
Can also be associated with papillary muscle rupture
Marasco. Heart, Lung and Circulation, 2008.

24. Prosthetic Valve Failure
Alexander. Circulation, 1995.

25. Prosthetic Valve Failure
Novarro. JASE, 2000.

26. St Jude Mitral Valve
Butany. J Clin Path, 2005

27. Physical Exam Findings
Brisk carotid upstrokes, laterally displaced forceful apical impulse
Murmur: characteristics don’t reliably predict severity
Similar to AS, TR and VSD
Constant intensitiy, holosystolic, loud blowing, apical with axillary radiation
Dimimished S1, split S2, possible S3 and loud P2
Highly variable depending on structures involved

28. Dynamic Auscultation Intervention
Hypertrophic Obstructive Cardiomyopathy
Aortic Stenosis
Mitral Regurgitation
Mitral Valve Prolapse
Valsalva ↑ ↓
↑ or ↓
Standing
↑ or unchanged
Handgrip or squatting
↓ or unchanged
Supine position with legs elevated
Unchanged
Exercise
Amyl nitrite ↑↑
Isoproterenol
Libby. Braunwald’s Heart Disease. 8th Ed.

29. XR Findings Prominent left atrial enlargement
Left ventricular enlargement
Pulmonary edema in acute MR
Enriquez-Serano. Contemporary Cardiology, 2009.

30. Atrial Fibrillation Affects 50% of Patients Within 10 Years
Enriquez-Serano. Contemporary Cardiology, 2009.

31. Acute Mitral Regurgitation Elevated PAP and Large PCWP V Waves
Libby. Braunwald’s Heart Disease. 8th Ed.

32. Variable Presentations of Mitral Regurgitation
Enriquez-Serano. Contemporary Cardiology, 2009.

33. Mitral Regurgitation Severity By Echo
Structural
LA size
LV size
Mitral leaflets and apparatus
Doppler
Jet area and characterisitics
Mitral inflow
Pulmonary vein flow
Quantitative
Regurgitant orifice area
Vena contracta
Right ventricle
Zoghbi. JASE, 2003.

34. Medical Management Diuretics to maintain euvolemia
Digoxin and beta blocker for rate control
Medical therapy directed at underlying ischemia
No benefits to vasodilators
Afterload reduction and inotropic support in acute mitral regurgitation

35. Survival: Medical Management of Organic MV Regurgitation
Mild
Moderate
Severe
Enriquez-Serano. Contemporary Cardiology, 2009.

36. Mitral Valve Prolapse Repair
Foster. NEJM

37. Prosthetic Mitral Valve
Bloomfield. Heart, 2002.

38. Survival After Surgical Correction By EF
Libby. Braunwald’s Heart Disease. 8th Ed.

39. Repair vs Replacement Repair can be accomplished in 80-90% Advantages
Possible lower mortality rates
Possible reduced need for anticoagulation
Lower risk of endocarditis
Foster. NEJM

40. Possible Survival Benefit With Mitral Valve Repair
Shuhaiber. EJCTS, 2007.

41. Chronic Severe MR
Bonow. JACC, 2006.

42. Percutaneous Therapies
1/3 of European patients with severe valve disease are denied surgery
1/2 of patients with severe symptomatic MR
Piazza. JACC, 2009.
Feldman. JACC, 2009

43. Mitral Stenosis Most commonly from rheumatic fever: 99%
2-20 years until symptoms of MS
Likely worsened by recurrent RF
Also
Congenital
CTD, RA
Mucopolysaccharidoses
Mimicks
Tumors
Infection
membranes

44. Hemodynamics Normal valve orifice 4-6 cm2
Small valve area requires higher pressure gradient
Symptoms precipitated by fast heart rate
Higher LA-LV pressure gradient
Lower cardiac output
Libby. Braunwald’s Heart Disease. 8th Ed.

45. Hemodynamics: Why Symptoms Develop
Increased left atrial pressure
Increase in left ventricular diastolic pressure
Pulmonary hypertension
Everything is worse with exercise
Chronic atrial changes lead to arrhythmia

46. Clinical Findings Presentation Exam findings
Dyspnea, hemoptysis, chest pain, arrhythmia, embolic events, hoarseness
Exam findings
Accentuated S1
Opening snap- at the apex with the diaphragm
A2-OS snap good indicator of severity
Findings of pulmonary hypertension
Low pitched rumbling murmur at the apex
Maneuvers that increase mitral flow increase murmur and decrease A2-OS time

47. Echo Determinants Of Mitral Stenosis Severity
Baumgartner. JASE, 2009.

48. Echo Determinants Of Mitral Stenosis Severity
Mild
Moderate
Severe
Valve Area (cm2)
>1.5
<1.0
Mean Gradient (mmHg)
<5
5-10
>10
PAP (mmHg)
<30
30-50
>50

49. Mitral Valvuloplasty Score
Baumgartner. JASE, 2009.

50. Natural History of 159 Patients With Un-Operated Mitral Valve Disease
Expected survival
Mitral stenosis
Mitral regurgitation
Libby. Braunwald’s Heart Disease. 8th Ed.

51. Management Approach to Mitral Stenosis
Nobuyoshi. Circulation, 2009.

52. Percutaneous Valvuloplasty
Nobuyoshi. Circulation, 2009.

53. Long Term Outcome For Percutaneous Valvuloplasty
Libby. Braunwald’s Heart Disease. 8th Ed.

54. Endocarditis Prophylaxis
Prosthetic valve material
Prior endocarditis
Congenital heart disease
Unrepaired cyanotic
For 6 months following repair with prosthetic material
Following incomplete repair with prosthetic material
Transplant recipient with abnormal valves