1、Valvular Heart Disease,Ni Chao, M.D. Division of Cardiology,Objectives,To understand the pathophysiology of the major VHDs To learn how to examine the patient To understand the principles of laboratory diagnosis To learn the fundamentals for treatment of cardiac valve abnormalities,Mitral Stenosis,E
2、tiology,Almost always the result of rheumatic fever Less common causes Congenital MS Systemic lupus erythematosus Rheumatoid arthritis Atrial myxoma Bacterial endocarditis.,Epidemiology,Rare in industrialized countries in patients 40 Very common in developing countries, esp. South Asia with severe d
3、isease often at early age (20) 2/3 of all patients with MS are female. The onset of symptoms is usu. between the 3rd and 4th decades.,Pathology,The mitral valve area (MVA) is normally 4-6 cm2 in adult Acute rheumatic fever causes immune-medi-ated inflammation of the mitral and other valves The leafl
4、ets thickened and the commissures fused along with thickening and shortening of the chordae tendineae narrowing of the mitral valve orifice,Pathophysiology,MVA reduced to 2 cm2: increased left atrial pressure (LAP) is necessary for normal trans-mitral flow MVA reduced to 1cm2: a LAP of 25 mm Hg is r
5、equired a rise in: Pulmonary venous preesure (PVP) Pulmonary capillary wedge pressure (PCWP)exertional dyspnea,Pathophysiology,Progressive dilation of the LA predisposes mural thrombi and atrial fibrillation Chronic elevation of LAP pulmonary hypertension, tricuspid and pulmonary re-gurgitation righ
6、t heart failure,Pathophysiology,Patients at high risk are of mural thrombi over 35 years old atrial fibrillation with a low cardiac output (CO) having a large left atrial appendage. Atrial fibrillation in up to 40% of patients decreases CO by 20%.,Clinical Manifestations,Histories of rheumatic fever
7、, murmur Dyspnea Palpitations Chest pain Hemoptysis Edema Thromboembolism,Physical Examination,Low-pitched diastolic rumble Opening snap S1, atrial fibrillation, P2 RV heave Elevated neck veins, hepatomegaly, ascites, pedal edema Coexistent murmurs Thromboembolic events,Chest X-Ray,Left atrial enlar
8、gement Pulmonary edema Prominence of pulmonary arteries Enlargement of right ventricle,EKG,Left, right atrial abnormalities atrial fibrillationRight Venticular hypertrophy,Echocardiogram,Enlarged LA Markedly thickened, often calcified MV with very narrow, “fish-mouth“ shaped orifice Delayed LV filli
9、ng with transmitral gradient in diastole,Echocardiogram,RV hypertrophy, RV hypokinesis TV thickness, stenosis or regurgitation Pulmonary hypertension LV function usually preserved,Severity of Mitral Stenosis,Natural History,In industrialized countries, 20-25 year latent period between episodes of rh
10、eumatic fever and clinical signs of MS Once mild symptoms develop, progression to complete disability is very rapid (5 years) without intervention Time course more fulminant in developing countries,ManagementMedical,Salt reduction Diuretics Control of heart rate with digoxin Anti-arrhythmic drugs Pr
11、evention of thromboemboli with adequate anti-coagulants,ManagementSurgical,Interventional therapy indicated for mitral valve area of 1.0 cm2 Mitral commisurotomy or mitral valve replace-ment are common surgical approaches For selected patients (primarily young with pure MS), mitral balloon valvulopl
12、asty is a successful option,Mitral Regurgitation,EtiologiesAcute,Endocarditis (most often caused by Staphylo-coccus aureus) Papillary muscle rupture (from infarction) or dysfunction (from ischemia) Chordal rupture (from myxomatous valvular disease),Etiologies Chronic,Rheumatic fever Mitral valvular
13、prolapse Marfan syndrome Cardiomyopathy,PathophysiologyAcute,Abrupt elevation of LA pressure in setting of LA with normal size and compliance Backflow into pulmonary circulation with elevated PVP and PCWP and pulmonary edema Decreased forward flow of CO, hypotension and shock occur often,Pathophysio
14、logy Chronic,Gradual elevation of LA pressure with dilat-ation of LA and LV Increased preload and eccentric LV hyper-trophy, LV function falls Elevated pulmonary vascular filling Pul-monary hypertension,Clinical manifestations,Dyspnea on exertion Paroxysmal nocturnal dyspnea Orthopnea Palpitations E
15、dema,Physical Examination,Laterally displaced PMI, RV heave Holosystolic murmur S3 gallop Atrial fibrillation Loud, palpable P2 Signs of endocarditis Thromboembolic events,Chest X-ray,Dilated LV (chronic) Pulmonary vascular redistribution (chronic) pulmonary edema (acute and chronic),EKG,Left ventri
16、cular hypertrophy Left or/and right atrial enlargement Atrial fibrillation Nonspecific ST-T wave changes Ischemic ST-T wave changes Myocardial infarction,Echocardiogram,Dilated LA, LV, RA, RV Decreased LV function Mitral regurgitation Segmental wall motion abnormalities (if in-farction) Vegetations
17、(if endocarditis),Severity of Mitral Regurgitation,Exercise Radionuclide Ventriculography,Fall in LV ejection fraction (5% decline in ejection fraction) indicating incipient LV dysfunction Dilated LV, LA, RV, RA,Cardiac Catheterization,Elevated LVEDP, PVP, PCWP and PAP Coronary artery occlusions (if
18、 infarction),Natural History,Time course is variable for chronic form Extent of LV cavity dilatation is inversely related to survival 5 year survival of patients treated medically is 45-80% depending on exercise limitation Acute form is associated with much higher mortality,Management Medical,Salt r
19、eduction Diuretics Digoxin Vasodilators (ACEIs, nitrates, hydralazine) Anticoagulation Anti-arrhythmics Intra-aortic balloon pump (IABP),Management Surgical,Mitral valve repair or replacement: must be performed before LV function too seriously compromised,Aortic Stenosis,Etiologies,Bicuspid aortic v
20、alve (most common con-genital anomaly) Calcification of tri-leaflet aortic valve Congenital unileaflet valve Rheumatic fever (1% of patients with isolated aortic valve disease - usually also involves mitral valve),Epidemiology,Largest group is 70-90 y/o with disease on tri-leaflet valves Next larges
21、t group is 45-60 y/o with disease on bicuspid aortic valves There is also a small group of patients with congenital AS,Pathophysiology,Obstruction to LV outflowthe LV hyper-trophies Aadequate cardiac output at rest preserved for years with increasing trans-aortic gradient,Pathophysiology,When the AV
22、A0.7 cm2, CO may be normal at rest but fails to rise with exertion due to obstruction to LV emptying from stenotic valve The LV dilates with longstanding AS,Pathophysiology,Progressive LV dysfunctiona fall in SV, CO and the LV-aortic gradient while the LAP, PCP, PAP, LVDP, RVDP increase The dilatati
23、on of mitral valve annulus MR the LV mass increases, diminished LV com-pliance, increased diastolic stiffness,Clinical Manifestations,Syncope Angina Heart failure Emboli Endocarditis,Physical Exam,Loud systolic murmur, radiates to the neck Sustained point of maximal impulse Diminished and delayed ca
24、rotid upstroke (parvus et tardus) Precordial thrill Single, soft S2 valve, S4 Aortic ejection sounds (heard after S1),Chest X-ray,Calcific aortic valve Tortuous aorta LA enlargement LV enlargement (late),EKG,LV hypertrophy LA abnormality Interventricular conduction delay,Echocardiogram,LV hypertroph
25、y Thickened, immobile aortic valve Dilated aortic root (post-stenotic dilatation) LV-aortic gradient LA enlargement MR, LV dilatation (late),Severity of Aortic Stenosis,Cardiac Catheterization,LV- aortic gradient Coexistent coronary artery disease may be present but is unrelated to development of AS
26、,Natural History,May be asymptomatic for years despite severe obstruction Development of certain symptoms portends a bad prognosis Aangina (average survival 3 years) Syncope (average survival 2 years) Heart failure average survival 1.5 years),Management Medical,Endocarditis prophylaxis Anti-arrhythm
27、ics No specific role for medical therapy,Management Surgical,Aortic valve replacement: improved survival and LV function even in those with pre-operative LV dysfunction as well as in octogenarians Aortic balloon valvuloplasty: purely palliative, survival or adequate long-term benefits improved not i
28、mproved Reserved for pt who cannot tolerate surgery.,Aortic Regurgitation,Etiologies Acute,Infective endocarditis Trauma Aortic dissection,Etiologies Chronic Primary valvular,Rheumatic fever Bicuspid valve Marfan Ehlers-Danlos Ankylosing spondylitis Lupus,Etiologies Chronic Aortic root disease,Syphi
29、lis Osteogenesis imperfecta Aortic dissection Behcet syndrome Reiter syndrome Hypertension,Pathophysiology Chronic,The entire SV ejected into the high pressure aorta in aortic regurgitation (AR) Part of the SV leaks back into the ventricle during diastole An increase in LVEDV to maintain effective f
30、orward flow,Pathophysiology Chronic,LV dilatation occurs as does a significant increase in LV stress The LV mass dramatically increases, often greater than LV mass in AS LVEDP remain relatively normal until late in disease LVEF usually normal and may increase with exercise,Pathophysiology Chronic,A
31、fall in the LVEF with exercise portends the onset of intrinsic LV dysfunction With longstanding AR, LV dysfunction en-sures with decreased LVEF, SV, CO and increased LVEDP, LAP, PVP and PCWP,Pathophysiology Acute,The ventricle does not have time to dilate in response to the increased ventricular loa
32、d With part of the stroke volume leaking back into the ventricle in diastole, the effective CO falls The rapid rise in LV pressure due to acute AR causes the mitral valve to close early,Clinical Manifestations,Dyspnea on exertion Paroxysmal nocturnal dyspnea Orthopnea Palpitations Angina Cyanosis/sh
33、ock (acute),Physical Examination Chronic,Diastolic decrescendo murmur Dilated point of maximal impulse Rapidly collapsing pulse (water-hammer or Corrigan pulse) Head bobbing (deMusset sign) Capillary pulsations (Quincke pulses) S3,Physical Examination Chronic,Wide aortic pulse pressure with systolic
34、 hypertension Pistol-shot sounds of the femoral arteries Low pitched diastolic rumble due to narrowing of mitral valve orifice by AR jet (Austin-Flint),Physical Examination Acute,Normal pulse pressure Soft or absent S1 Soft diastolic murmur Cyanosis, shock, vasoconstriction,Chest X-ray,Enlarged LV T
35、ortuous, dilated aorta (mainly chronic),EKG,LV hypertrophy (chronic but not acute form) Interventricular conduction delay PR prolongtion,Echocardiogram,Chronic form: dilated LV; marked LV hyper-trophy, dilated aortic root, aortic regurgitation, enlarged LA, thickened aortic valve Acute form: normal
36、LV cavity size, aortic regurgitation, early closure of mitral valve,Severity of Aortic Regurgitation,Radionuclide Ventriculography,Dilated LV Normal LV ejection fraction at rest with fall in ejection fraction with exertion (chronic form),Cardiac Catheterization,Chronic: markedly dilated LV; coronary
37、 arteries often normal despite angina; aortic root injection of contrast dye shows severity of AR. LV end-diastolic pressure elevated only late in chronic form of disease Acute: normal LV cavity size; very high LV end-diastolic pressure,Natural History,Chronic Survival is 75% at 5 years Once symptom
38、atic, death usually occurs within 4 years of angina and 2 years of heart failure Acute form has high mortality without surgical repair,Management Chronic,Mild or moderate AR or severe AR in patients with good exercise tolerance and normal LV function can be managed with salt restriction, diuretics, vasodilators Patients with severe AR and symptoms or with evidence of LV dysfunction should be considered for aortic valve replacement,Management Acute,Medical emergency requiring urgent surgical replacement of damaged aortic valve IABP contra-indicated (would increase AR),
