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enlargement and annular dilatation
with or without left ventricular dysfunction. This pathophysiological process has had more recognition in recent years. 12
DIAGNOSIS
History and physical examination
ASSESSMENT of patients with
chronic MR begins with a detailed medical history and physical examination. In those with chronic MR, symptoms may vary from asymptomatic to severely dyspnoeic.
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SMART-Servier Medical Art / CC BY / bit. ly / 3HN8rtH |
MRI( CMR) and invasive right and left heart catheterisation. CMR is generally more accurate and reproducible than catheterisation for quantitating MR volume, LV volume and LV ejection fraction( LVEF). 19 Left ventriculogram, invasive measurement of cardiac output and pulmonary pressures can provide additional information to inform decision making regarding treatment.
MANAGEMENT
General considerations
DECIDING on the best treatment for
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Absence of symptoms in the chronic |
MR is based on multiple variables, |
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phase may be explained by pro- |
including the type, severity, patient |
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gressive left atrial enlargement; |
comorbidities, associated cardiac |
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this allows for accommodation of |
changes and experience of the treat- |
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the large regurgitant volume in the |
ing centre. A comprehensive assess- |
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dilated left atrium without a signifi- |
ment of patient history, physical |
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cant increase in pressure, which does |
examination and diagnostic tests in a |
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not then cause dyspnoea. Patients |
specialised heart valve centre is vital |
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typically tend to reduce their activity |
to provide individualised treatment |
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to avoid symptoms. It is important |
for each patient. 10 |
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to ask the patient and family members what the patient can currently undertake compared with their previous activities. Exercise testing may |
Primary mitral regurgitation
Medical therapy has a limited role
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unmask symptoms in asymptomatic |
in acute MR. Diuretics can be used |
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patients. 13 |
to reduce filling pressures and ino- |
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As the compensatory mech- |
tropic agents to increase contractil- |
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anisms become overwhelmed, |
ity. There is no evidence to support |
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patients develop a gradual reduction in exercise tolerance and exertional shortness of breath. Fatigue and pal- |
the use of medical therapy in chronic stable MR and preserved LVEF. 13 In patients with MR and reduced LVEF, |
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pitations are also common symp- |
guideline-directed heart failure ther- |
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toms of severe MR. |
apy is needed, in conjunction with |
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Regarding physical examination, |
20, 20A other treatments. |
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complete assessment of MR always |
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includes evaluation for fluid overload, signs of heart failure and suggestive heart sounds( see figure 5). |
Figure 1. Chronic mitral regurgitation. |
INTERVENTION The European Society of Cardiology guidelines for the treatment |
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Common signs of MR include a dis- |
of MR appear in figure 8. In sum- |
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placed apex beat, loud systolic murmur and cardiomegaly. 14 In patients with primary MR, the presence of S3 plus a short diastolic murmur is usually associated with a significant MR. 14 Radiation of the murmur of primary MR can provide a hint regarding the underlying leaflet pathology. Murmurs from the anterior leaflet are |
BruceBlaus / CC BY / bit. ly / 3SDk396 |
mary, intervention is indicated in all asymptomatic patients with severe MR. Intervention is also indicated in patients with severe MR and highrisk features like reduced LVEF, enlarged left atrium and increased pulmonary pressures.
If no symptoms or high-risk features are present, watchful waiting
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generally directed towards the axilla, while murmurs from a flail posterior leaflet radiate anteriorly. Second- |
with close follow-up is a reasonable option. 15 When intervention is indicated surgery remains the first line |
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ary MR murmurs are generally best |
of therapy, unless the heart team rec- |
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heard at the apex. Atrial fibrillation |
ommends against it, because of its |
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and other arrythmias are commonly |
greater higher efficacy in treating pri- |
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associated with MR. 14 |
mary MR. 21 |
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Investigation
Transthoracic echocardiogram( TTE)
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If the heart team decide that the patient is suitable for surgery, then valve repair, not replacement, is the |
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and transoesophageal echocardio- |
first surgical choice, because valve |
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gram( TOE, the gold standard) are |
repair is associated with a greater |
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vital investigations to diagnose, evaluate severity, assess anatomy, aetiology, mechanism, associated findings, |
life expectancy compared with MV replacement. 5 Successful repair of primary MR at the right time and |
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and guide choice of therapy in MR. 3 TTE( 2D images and doppler) is the |
performed in an experienced centre results in life expectancy similar to |
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initial assessment, given its non-invasive nature and easy availability.
When assessing the severity of
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that of normal age-matched population. 22 When repair is not possible, MV replacement is a good alternative |
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MR, guidelines recommend integra- |
option. 22 |
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tion of qualitative( for example, MV |
While surgery remains the first |
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morphology and colour flow jet area), |
choice for patients with primary MR, |
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semiquantitative( vena contracta |
surgical risk is prohibitive in a large |
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[ the narrowest part of the jet that is |
percentage of patients because of |
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just distal to the regurgitant orifice ] |
old age and comorbidities. In these |
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width and pulmonary vein flow), and |
patients, transcatheter MV implan- |
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quantitative( regurgitant volume and |
tation is a safe option. Transcatheter |
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regurgitant orifice area) measures in |
MV repair is an emerging technol- |
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15, 16 the assessment.
While in some cases TTE provides sufficient information for assessment of MR, TOE is mostly needed for a
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Figure 2. Mitral valve regurgitation. |
ogy in cardiology, and it is rapidly evolving. Because of the complexity of MV apparatus, there are multiple devices in the experimental |
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full assessment. TOE provides better quality images, and it is more accurate in the assessment of eccentric jets. 17 In addition, the‘ en face’ view of the MV obtained using 3D echo |
helps visualise the anatomic details of the MV apparatus and differentiates between primary and secondary MR with high level of certainty. 3D TOE is highly precise in locating prolapsing |
scallops( P1 [ anterior or medial scallop ], P2 [ middle scallop ], and P3 [ posterior or lateral scallop ]; see figures 6 and 7), and can be used to understand highly specific details required |
for both surgical and transcatheter repair. 18
Other modalities( very rarely indicated) that can be useful in assessment of MR are non-invasive cardiac
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phase. Currently, transcatheter MV edge to edge repair( TEER) using mitral clip( Abbott Vascular) or PAS- CAL( Edwards Lifesciences) devices are the most mature, with the most |