Valvular heart disease. Mitral valve презентация

Natural History of
Mitral Regurgitation
With acute mitral regurgitation, left atrial compliance is predominantly fixed; therefore the left atrial pressure and pulmonary capillary wedge pressure can rise dramatically if the regurgitant volume is sufficiently large, resulting in pulmonary edema.

Chronic Mitral Regurgitation
Patients with chronic mitral regurgitation will have a long latent period before becoming symptomatic

Mitral Regurgitation hemodynamics
In patients with significant mitral regurgitation, prominent v-waves are seen on the left atrial pressure tracing due to simultaneous antegrade and retrograde filling of the left atrium from pulmonary venous inflow and mitral regurgitation. With pure mitral regurgitation, a rapid y-descent may also be present due rapid antegrade flow across the mitral valve as a result of the elevated left atrial to left ventricular pressure gradient

Symptoms
Fatigue & weakness – due to ? CO – predominant complaint
Exertional dyspnea & cough – pulmonary congestion
Palpitations – due to atrial fibrillation (occur in 75% of pts.)
Edema, ascites – Right-sided heart failure

Sings
Atrial fibrillation
Cardiomegally
Apical pansystolic murmur +/- thrill
Soft S1, apical S3
Signs of pulmonary venous congestion (crepitations, pulmonary edema, effusions)
Signs of pulmonary hypertension & right heart failure

escardio.org
2017

Rick A. Nishimura et al. Circulation. 2014;129:2440-2492

Type IIIb (restricted leaflet closing)
▪ Regional/global LV dysfunction
▪ LV & Papillary muscles geometry changes
▪ Papillary muscles ischemic damage
▪ MV annulus dilatation;
▪Posterior leaflet restriction

MitraClip device

Mitral Stenosis

Mitral Stenosis Etiologies:
Rheumatic valvular disease - the most common cause of mitral stenosis.
Congenital deformities - infancy or early childhood.
Systemic Diseases - systemic lupus erythematosus, rheumatoid arthritis or carcinoid syndrome.
Pseudo-mitral stenosis -anatomically normal . Obstruction of transvalvular flow is caused by an extrinsic structure such as a cardiac tumor (most commonly an atrial myxoma), large vegetations, physiological rather than anatomical restriction of mitral leaflet excursion, as can be seen with severe aortic regurgitation, or congenital atrial membranes as seen with cor triatriatum.
Dense mitral annular calcification (MAC) - with extension into the mitral valve leaflets and restriction in leaflet motion.

Rheumatic Valvular Disease
Rheumatic fever is a collagen vascular disorder which occurs following group A beta-hemolytic streptococcal infections (strep throat).
Develops several weeks following an acute strep infection
Presents as a multi-systemic inflammatory condition (involving the heart, joints and CNS system)
Histologically, rheumatic fever is characterized by inflammatory changes leading to damage of collagen fibers and ground substance in connective tissue

Rheumatic Mitral Stenosis

Acute Rheumatic Fever:
Modified Jones’ criteria
Major
Carditis (Myocarditis, pericarditis, valvulitis)
Polyarthritis
Sydenham’s chorea
Subcutaneous nodules
Erythema marginatum
Minor
Arthralgia
Fever
Raised ESR/cRP
EKG: prolonged PR interval
Diagnosis requires:
2 major criterion
1 major + 2 minor criterion

Acute Rheumatic Fever: Presentation

Acute Rheumatic Fever:
Some clinical signs
Erythema marginatum

Acute
Phase
Chronic
Phase
valve leaflet inflammation can result in transient regurgitant murmurs and mid diastolic murmurs (the latter known as a Carey-Coombs murmur) due to turbulent blood flow across inflamed valve leaflets.
there is progressive thickening and fibrosis of the mitral valve commissures, leaflets and chordae leading to valvular stenosis or a combination of stenosis and regurgitation.

Mitral Valve Stenosis: Sings
Palpation:
Small volume pulse
Tapping apex-palpable S1
Palpable S2
Atrial fibrillation
Signs of raised pulmonary capillary pressure
Crepitations, pulmonary edema, effusions
Signs of pulmonary hypertension
RV heave, loud P2
Auscultation:
Loud S1
S2 to OS interval inversely proportional to severity
Diastolic rumble: length proportional to severity
In severe MS with low flow- S1, OS & rumble may be inaudible

Hemodynamics of MS
Left ventricular pressure rises above left atrial pressure in early systole causing the mitral valve to close. This corresponds with S1.
Following valve closure, the mitral valve rebounds into the left atrium causing a small deflection in the left atrial pressure tracing which corresponds with the c-wave.
Left atrial pressure increases during ventricular systole as a result of left atrial filling from the pulmonary venous return. This increase in atrial pressure corresponds with the v-wave.
When left atrial pressure rises above the descending portion of the left ventricular pressure curve, the mitral valve opens marking the beginning of ventricular diastole, during which the left atrium empties and left atrial pressure falls.
During late diastole, the left atrium contracts, creating a transient increase in the left atrial pressure tracing. This corresponds with the a-wave.

Mitral Valve Stenosis
HEMODYNAMICS

What is the impact of chronic elevation in left atrial pressures on the remainder of the cardiopulmonary system?
Blood flows from the superior vena cava (SVC) and inferior vena cava (IVC) right atrium (RA), across the tricuspid valve (TV) the right ventricle (RV) blood is ejected into the pulmonary artery (PA) pulmonary capillary bed (PC) pulmonary veins (PVs) left atrium (LA), across the mitral valve (MV) left ventricle (LV) pumped into the systemic circulation.
Under normal conditions, left atrial and left ventricular pressures are equal at the end of diastole when the mitral valve is fully opened.

With mitral stenosis, there is impedance to left atrial emptying.
Left atrial pressure rises to maintain antegrade flow across the stenotic valve, creating a pressure gradient between the LA and LV.
This elevation in LA pressure is passively transmitted back across the pulmonary vascular bed leading to pulmonary hypertension through passive congestion.
This is sometimes referred to as post-capillary block.

With ongoing passive congestion, reactive vasoconstriction occurs in the pre-capillary beds (“pre-capillary block") causing additional increases in pulmonary arterial and right heart pressures.
This, in turn, contributes to progressive RV enlargement and dysfunction.
If left uncorrected, obliterative changes may occur in the pulmonary vascular bed, in the form of intimal hyperplasia and medial hypertrophy, which over time, contribute to worsening pulmonary hypertension.

Precapillary Block
Fatigue
Exhaustion
Weakness
Tiredness
Right-sided failure
Edema, hepatomegaly
Tricuspid insufficiency
Cyanosis(peripheral)
Large heart
Mild jaundice
Hoarseness
Signs and symptoms of low CO
Postcapillary Block
Dyspnea, DOE
Orthopnea, PND
Pulmonary edema
Hemoptysis, cough
Left-sided failure
Small heart
Pulmonary congestion
No edema

With ongoing passive congestion, reactive vasoconstriction occurs in the pre-capillary beds (“pre-capillary block") causing additional increases in pulmonary arterial and right heart pressures.
This, in turn, contributes to progressive RV enlargement and dysfunction.
If left uncorrected, obliterative changes may occur in the pulmonary vascular bed, in the form of intimal hyperplasia and medial hypertrophy, which over time, contribute to worsening pulmonary hypertension.

Mitral Valve Stenosis: Symptoms
Dyspnea and cough (pulmonary vascular congestion and pulmonary hypertension)
Orthopnea (related to positional increases in preload when assuming a supine position)
Chest pain (related to right ventricular hypertrophy and pulmonary hypertension)
Hoarseness (compression of the recurrent laryngeal nerve from a dilated pulmonary artery. (Ortner’s syndrome) )
Peripheral edema (pulmonary hypertension, right heart failure, and chronic elevation in peripheral venous hydrostatic pressure)
Fatigue (low output state)
Systemic thromboembolism

Auscultatory findings
With a structurally normal mitral valve, there is no significant LA to LV diastolic pressure gradient at end diastole.
In the absence of medical conditions causing hyperdynamic flow, no diastolic murmur should be appreciated.

With mild mitral stenosis, left atrial pressure is elevated creating a LA to LV pressure gradient during early diastole. This pressure gradient results in turbulent flow which can be appreciated on cardiac auscultation as a low pitched diastolic murmur often referred to as a diastolic rumble.
As the LA to LV pressure gradient equilibrates towards mid diastole, the rumble diminishes or disappears, but can reappear in late diastole during atrial contraction with pre-svstolic accentuation of the murmur.
Auscultatory findings

As mitral stenosis increases in severity, left atrial pressure continues to rise to a point where the LA to LV pressure gradient persists throughout diastole generating diastolic rumble which persist throughout the diastolic filling period. This is often described as a holodiastolic rumble.
In addition, the severity of mitral stenosis can be assessed based on the timing of the closure of the aortic valve (S2) and onset of the mitral valve opening snap.
Auscultatory findings

S1 S2 OS S1
First heart sound (S1) is loud and snapping
Opening snap (OS)
Low pitch diastolic rumble at the apex
Pre-systolic accentuation
Mitral Valve Stenosis:
Physical Examination

Mitral Valve Stenosis: Pathophysiology
Normal valve area: 4-6 cm2
Mild mitral stenosis:
MVA 1.5-2.5 cm2
Minimal symptoms
Mod. mitral stenosis
MVA 1.0-1.5 cm2 usually does not produce symptoms at rest
Severe mitral stenosis
MVA < 1.0 cm2
Symptoms occur mitral valve orifice <2cm²

Chest XR

Type IIIa (restricted leaflet opening)
Domelike anterior leaflet movement, restriction of posterior leaflet
subvalvular fusions

Rick A. Nishimura et al. Circulation. 2014;129:2440-2492

Rick A. Nishimura et al. Circulation. 2014;129:2440-2492

Rick A. Nishimura et al. Circulation. 2014;129:2440-2492

Rick A. Nishimura et al. Circulation. 2014;129:2440-2492

Percutaneous balloon valvuloplasty
Carpentier A. “Reconstructive valve surgery” 2010

Percutaneous balloon valvuloplasty

Mitral Valve Repair
Carpentier A. “Reconstructive valve surgery” 2010