Primary mitral valve regurgitation Daniela Panayotova University - - PowerPoint PPT Presentation

Primary mitral valve regurgitation

Daniela Panayotova University Hospital St. Marina Varna, Bulgaria

Normal mitral valve structure

Normal mitral valves leaflets have four well-defined tissue layers, from the atrial to the ventricular aspect, these layers were the Auricularis, the Spongiosa, the Fibrosa, and the Ventricularis Each layer, containing characteristic cells and extracellular matrix, plays a different role

normal mitral valve

• the average valve leaflet thickness of clear zone is 0.7–0.9 mm
• percentage of the Spongiosa in relation to the valve thickness was

variable but almost 10%–20%

The main pathological hallmarks in degenerative mitral valve disease

• Abnormal accumulations of mucopolysaccharide in the spongiosa
• Infiltration to the Fibrosa as a structural core for valve tissue
• The layered architecture is destroyed
• Valve thickening and structural fragility are induced
• Individual collagen bundles are fragmented, coiled, disrupted
• Decreased consistency is derived from the complicated structure
• Similar changes are observed in chordal tendineae

The main pathological hallmarks in degenerative mitral valve disease

Immune activity against extracellular matrix proteins (such as fibrin and elastin18) and collagen I and III19)

• Rabkins, et al. hypothesized that activated metalloproteinase (MMP) and

cathepsins secretion by valvular interstitial cells (VICs) in mitral valves mediates extracellular matrix degeneration in cases with myxomatous degeneration

Pathohistological differences betw een FED and BML

Histologic sections of BML. Mucopolysaccharide were widely infiltrating into the Spongiosa, which thickened the valve in the BML group, giving the appearance of cystic spaces Histologic sections of FED. Valve tissue is usually thinner than in BML and its four-layer architecture of the leaflet tissue is almost preserved proportion of the Spongiosa is 30% proportion of the Spongiosa is over 50%

Carpentier Classification of mitral regurgitation

Two diferent mechnisms of regurgitation

Billowing – systolic protrusion of leaflet body above the annulus

• plane. Free edge remaining at or

below the annular plane during end-systole Prolapse – free edge of the leaflet above the plane of the annulus at end-systole, disruption of coaptation

Lang RM, Tsang W, Weinert L, Mor-Avi V, Chandra S. J Am Coll Cardiol 2011

Classification

Carpentier, et al. classified patients with degenerative mitral valve disease into two different forms on the basis of clinical patterns and gross appearance:

billowing mitral leaflet (BML) Barlow’s Disease fibroelastic deficiency (FED)

Degenerative mitral valve disease is divided into several subtypes according to clinical variability

Lang RM, Tsang W, Weinert L, Mor-Avi V, Chandra S. J Am Coll Cardiol 2011

Difference betw een Barlow ’s Disease and Fibroelastic Deficiency

Barlow’s Disease (BML)

• severely dilated annulus
• multiple segments of the leaflet(s)

showed billowing into the atrial side thickened with excess tissue

• prolapse has a wide and low shape

as a “plateau”

• thickened, elongated and fused

chordae with occasional calcification

• Calcification of papilary muscles

Fibroelastic Deficiency

• localized prolapse with healthy

adjacent segments

• area of prolapse is small
• the leaflet is typically flail with a high

prolapse height as a “tower”

• elongation of the chords is localized in

a few segments

• visible ruptured chords
• in most of cases only posterior

leaflet(P2) is involved

• the annulus is not dilated or is only

slightly dilated

Clinical characteristics of degenerative mitral valve disease

Barlow’s Disease (BML)

• patients are more likely to be

middle- aged, and they have a long-term evolution of mitral valve insufficiency (10–20 years) FED

• elderly patients, who did not have

a long history of a murmur

• disease duration tended to be

shorter and presented frequently with ruptured chordae

Special characteristics of BML

The posterior leaflet displaced toward the LA free wall away from the ventricular hinge → cul-de-sac along posterior annulus →anular fissures and calcification

Differentiation of Barlow ’s Disease From FED Using Prolapse Height, Volume

Chandra S, Lang RM et al., Circ Imaging 2011

Differentiation of Barlow ’s Disease From FED Using Prolapse Height, Volume, and PV-PH Ratio

FED ← 1.15ml ˃ PV ˃ 1.15ml → Barlow In some cases FED PV ˃ 1.15ml → PV-PH ratio, a novel parameter of prolapse, was able to differentiate Barlow’s disease from FED more precisely than crude prolapse volume or height PV-PH ratio Barlow ˃ 0.3 PV-PH ratio FED ˂ 0.3

Grading mitral regurgitation severity

Zoghbi WA, Enriquez-Sarano M, et al. J Am Soc Echocardiogr. 2003;16:777802.

Stages of primary mitral regurgitation

Nishimura et al 2014 AHA/ACC Valvular Heart Disease Guideline

Predictors of poor outcome in primary MR

Clinical characteristics Biologic markers Echo findings Advance age Elevated BNP Low EF ˂ 60% Symptoms of CHF EROA ˃ 40mm² Atrial fibrilation Left atrial index ≥ 60ml/m² Poor exercise capacity Pulmonary hypertemsion Abnormal LV strain

Outcome of Asymptomatic degenerative Mitral Regurgitation

Patients with a left atrial index 40 ml/m2 have lower 2-year survival and more cardiac events than those with mild or no left atrial enlargement. In this cohort, mitral surgery is associated with decreased mortality and cardiac events.

Julien Magne Heart 2012;98:584e591

Outcome of Asymptomatic degenerative Mitral Regurgitation

Maurice Enriquez-Sarano, M.D., N Engl J Med 2005;352:875-83.

456 patients (mean [±SD] age, 63±14 years; 63 percent men; ejection fraction, 70±8 percent) with asymptomatic organic mitral regurgitation, quantified according to current recommendations (regurgitant volume, 66±40 ml per beat; effective regurgitant orifice, 40±27 mm 2 ).

New biomarkers for primary mitral regurgitation

• High-density lipoprotein
• Apolipoprotein- A1
• Haptoglobin
• Haptoglobin-α2 chain

levels significantly decreased proportionally to the degree of mitral regurgitation when compared to controls

Indications for surgery for MR

Nishimura et al. JACC Vol. 63, No. 22, 2014 2014 AHA/ACC Valvular Heart Disease Guideline

Identify the prolapsing scallop( more then 3 segments)

Identify the prolapsing scallop (more then 3 segments)

Identify the prolapsing scallop (more then 3 segments)

Identify the prolapsing scallop( more then 3 segments+ruptured cords)

Identify the prolapsing scallop (A2)

Identify the prolapsing scallop (A2)

Identify the prolapsing scallop (P2)

Identify the prolapsing scallop (P2)

Identify the prolapsing scallop (P3)

Indicators for stress echocardiography in primary MR

• assessment of patients whose symptoms or LV dysfunction appear

disproportionate to the severity of MR at rest

• To define asymptomatic patients with severe MR with normal cavity

dimensions and good LV function

those who have a good prognosis who can avoid surgery those who are more likely to progress to symptoms and LV dysfunction who need surgery ear

Stress echocardiography for moderate MR

• 40mm² ˃ ERO ˃ 20mm²
• 60ml˃ RV ˃ 30ml

As a functional MR, degenerative MR can be dynamic with stress – induced changes One – forth of patients develop severe MR during stress

• ↑ ERO ≥ + 10 mm²
• ↑ RV ≥ + 15ml

Srtess Echo

Magne et al. JACC Vol. 56, No. 4, July 20, 2010:300–9

Changes in MR (RV)

RV ˃ 60ml 30ml ˂ RV ≤ 60ml

RV ˃ 60ml 30ml ˂ RV ≤ 60ml RV ≤ 30 ml

Changes in MR (ERO)

ERO ˃ 40 mm²

20mm² ˂ ERO ≤ 40mm² ERO ˃ 40mm² 20mm² ˂ ERO ≤ 40mm² ERO ≤ 20 mm²

Why does primary MR worsen during exercise?

• changes in LV and annular geometry
• papillary muscle traction, resulting in the fibrosis

Stress echocardiography -

correct identification of surgical candidates

EROA ↑ ˃ 10mm² RV ↑ ˃ 15ml Peak TR maximal velocity and calculation for PASP PASP ˃ 60mmHg Peak LVEF LVEF fail to improve by ≥4% Global longitudinal strain GLS fail to improve by ≥ 1.9% e BNP ↑ ≥ 90 pg/ml ( at rest ˃40 pg/ml)

Simptom-free survival

Magne et al. JACC Vol. 56, No. 4, 2010

Symptom-free survival of patients with marked exercise-induced increase in RV (≥ +15 ml) compared with those with marked decrease (˃ -15 ml) or no marked change (˂ +15 ml and ˃ -15 ml).

Prognostic importance of left ventricular longitudinal function in asymptomatic degenerative mitral regurgitation

Julien Magne Heart 2012;98:584e591

Prognostic importance of left ventricular longitudinal function in asymptomatic degenerative mitral regurgitation

reduction in GLS from rest reduction in GLS to exercise

Impact of a left Ventricular ejection index in asymptomatic primary MR

LV ejection index (LVEI) = Indexed LV end−systolic diameter LVOT TVI LVEI ˃ 1.13

• an independent predictor of postoperative LV dissfunction
• a powerful determinant of postoperative cardiovascular mortality

Impact of a left Ventricular ejection index in asymptomatic primary MR

LVOT TVI – 17,4 cm BSA – 1.75 m² Indexed LVESD – 14.9/m² LVEI – 0.84

The echocardiography – prediction of complexity of MV repair

• Multisegment involvement
• Anterior leaflet prolapse
• Scarcity of leaflet tissue
• Severe calcification
• Prolapsing height
• Annular dilatation ˃ 50mm

After MV repair