It’s Leaky... MITRAL REGURGITATION Rami Khouzam, MD Mitral Regurgitation • Anatomy: 3 basic mechanisms of MR: 1- Alteration of Mitral leaflets, commissures, or annulus 2- Defective tensor.

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Transcript It’s Leaky... MITRAL REGURGITATION Rami Khouzam, MD Mitral Regurgitation • Anatomy: 3 basic mechanisms of MR: 1- Alteration of Mitral leaflets, commissures, or annulus 2- Defective tensor.

It’s Leaky...
MITRAL REGURGITATION
Rami Khouzam, MD
Mitral Regurgitation
• Anatomy:
3 basic mechanisms of MR:
1- Alteration of Mitral leaflets, commissures, or
annulus
2- Defective tensor apparatus
3- Alterations of LV and LA size & function
1- Alteration of Mitral leaflets, commissures,
or annulus:
• MVP: most common cause of isolated MR.
Posterior leaflet more frequent and severe.
Greater in men. Increases with age.
• Rheumatic fever
• Mitral annulus calcification: age-related
• Infective endocarditis
• Congenital: cleft of anterior MV associated
with primum ASD
2- Defective tensor apparatus:
• Abnormal chordae tendineae: Idiopathic/
endocarditis/ MVP/ Trauma
• Papillary muscle dysfunction:
Posteromedial > anterolateral (vulnerability
to ischemia & infarction): single blood
supply
3- Alterations of LV and LA size & function:
• Alteration of position and axis of papillary
muscle
• Mitral ring dilatation
Key points...
• Mitral prolapse is the most common
cause of isolated MR
• Ischemia:  dysfunction/rupture of
papillary muscle. Posteromedial >
anterolateral
• LV enlargement & abnormal
contractile function are common
causes of MR
Pathophysiology of MR
1. Acute Stage
2. Chronic Compensated Stage
3. Chronic Decompensated Stage
Key points...
• Acute severe MR is characterized by normalsized chambers, high EF, & pulmonary
congestion.
• Chronic compensated severe MR is typified
by few symptoms, enlargement of the LV &
LA, and high EF
• Chronic decompensated severe MR is typified
by enlargement of the LV & LA, pulmonary
congestion, and normal to low EF
• A “normal range” EF in the setting of severe
MR usually implies LV systolic dysfunction
Clinical syndrome of MR
Acute MR
• If severe: pulmonary congestion
• S3 S4
• Systolic murmur: short, soft or absent
Chronic MR
Prolonged asymptomatic interval.
Fatigue/ generalized weakness
Laterally displaced, enlarged apical impulse
Severe MR: apical thrill
Early aortic closure
Holosystolic murmur: intensity does not correlate with
severity of regurgitant flow
Anterior leaflet MR: Radiates to axilla frequently
Posterior leaflet abnormality:  regurgitant flow anteriorly
 radiation to aortic area, and all precordium
Short diastolic apical rumble in the absence of MS: high
diastolic transmitral flow & severe MR
Key points...
• Acute severe MR: short or soft murmur because
of low LV-LA pressure gradient
• Nonspecific fatigue & weakness may represent
early symptoms of chronic severe MR
• Duration of apical impulse in chronic severe MR
is related to LV systolic function
• Posterior leaflet prolapse: murmur to aortic area
• Amyl nitrite distinguishes diastolic rumble of
mixed MS & MR () from that due to isolated
severe MR ()
Evaluation of MR
EKG
LAE
Atrial fibrillation
LVH
Nonspecific ST-T changes
CXR
LVE
LAE (straightening left border, atrial double density,
elevation of left main-stem bronchus)
Pulmonary venous congestion
Echocardiography
In some cases, TEE is better to assess the
anatomy of the MV, to rule out atrial
thrombus, gather supplemental data in
quantitative & qualitative measures of
regurgitation severity (but not always
necessary).
Determination of severity
Over 20 variables described.
Color flow Doppler
Atrial side:
Small jet occupying < 20 % of LA: mild
20- 40 %: moderate
Large jet > 40 % and extending into the pulmonary veins): severe
Ventricular side: PISA proximal flow acceleration (proximal
isovelocity surface area): concentric series of hemispheric rings of
alternating colors, each ring denoting an isovelocity of aliasing.
The diameter of the ring closest to the regurgitant orifice is
measured and, in severe mitral regurgitation, usually approaches
1 cm.
Pulsed and continuous wave Doppler of mitral inflow
E > 1.4 m/sec
E/A ratio > 2
(Finding an A-wave dominant pattern of mitral inflow makes
severe mitral regurgitation very unlikely).
Uniformly dense jet throughout its duration, well-defined
envelope
 TR peak velocity: pulmonary hypertension.
Doppler of pulmonary veins: show systolic flow reversal
Doppler of pulmonary veins
(pulse Doppler of the left and right upper pulmonary
veins from the apical four-chamber view). Normal
pulmonary venous flow is antegrade during both
ventricular systole and diastole (ventricular systolic
component dominates), with slight retrograde flow during
atrial systole. In hemodynamically severe mitral
regurgitation, the flow in one or more pulmonary veins
(depending upon the direction of the jet) will show
systolic flow reversal
Index of severity
Based on 6 variables, each scored on a scale of 0 to 3 then
averaged
1- Color Doppler regurgitant jet width and penetration
2- Color Doppler PISA diameter
3- Continuous wave Doppler characteristics of the regurgitant jet
4- Continuous wave Doppler TR derived PAP
5- Pulse wave Doppler pulmonary venous flow pattern
6- Left atrial size by 2D- echocardiography
(Mild MR: index 1.7, Severe MR (regurgitant fraction >40
percent) : index 1.8, A value 2.2 identified patients with severe
mitral regurgitation with a sensitivity, specificity, and positive
predictive value of 90, 88, and 79 percent, respectively).
Cardiac catheterization
Right heart cath: Prominent “V” wave on
PCWP tracing
Left heart cath/ Ventriculogram: Only when
- noninvasive data are discordant or
- technically limited or
- differ from the clinical perception of the
severity of MR or ventricular function.
Angiographic grading: many variables..
Sellars criteria
Key points...
• No EKG or CXR findings pathognomonic
of MR
• Echo is invaluable for assessing cause &
severity of MR, size and function of LV, LA,
RV
• Left ventriculography is most useful when
noninvasive data discordant or technically
limited or differ from clinical impression of
the severity of MR, or ventricular function
Mitral valve prolapse
• Click: systolic billowing of a portion of mitral leaflet into LA
• Maneuvers that ventricular preload (Valsalva, standing):
prolapse, click & murmur earlier in cardiac cycle.
• Progression to severe MR: more in men, and advancing age
• MVP & severe MR: managed as severe MR
• Antibiotic prophylaxis: when?
- Click & murmur, or
- Click & echo: significant leaflet thickening or regurgitation
• B-Blocker: for MVP/palpitations/atypical CP/anxiety
• ASA: TIA in the setting of MVP
Natural history of MR
• Depends on its cause
• Time course of progressive LV dysfunction
in chronic MR is variable & unpredictable
• Acute worsening of MR suggests chordal
rupture, infection, new arrhythmia, or
ischemia
Outcome after surgical correction of MR
(The unnatural history)
• Current surgical practice is to operate on patients with
severe MR before the development of heart failure or
ventricular dysfunction, if possible
• Preoperative EF: best predictor of long-term mortality,
CHF, & postoperative LV function
• End-systolic dimension: significant predictor
• A. fib more than 3 months preoperatively associated with
high risk of postoperative arrhythmia persistence and need
for long-term anticoagulation
Treatment of Acute severe MR
• i.v. vasodilators (Na nitroprusside),
i.v. inotropes, IABP
• Mitral valve Repair or Replacement
• Endocarditis: delay surgery if possible (risk
of recurrence), unless progressive heart
failure, unresponsive to antibiotics,
intracardiac abscess, recurrent systemic
embolization
Treatment of Chronic Nonischemic MR
• Dental hygiene/ Antibiotic prophylaxis
• Treat contributing underlying disease
• No data to indicate diuretics or vasodilators
(or both) provide morbidity or mortality
benefit
• Every patient should be considered for
surgery
Indications for surgery for chronic mitral
regurgitation
SYMPTOMS
LV EF
LVESD
NYHA II - IV
> 60 %
< 45 mm
Asymptomatic or symptomatic
50 - 60 %
= 45 mm
Asymptomatic or symptomatic
< 50 % or
= 45 mm
Pulmonary artery systolic pressure = 50 mmHg
MV REPAIR
Who gets it??
• Repair should be performed preferentially whenever
possible: favorable predictor of operative mortality, late
survival, postoperative EF.
• High risk patients: severe LV dysfunction (EF < 35 %,
CI < 1.5 L/min per m2)
• MR: posterior leaflet, non-rheumatic, noninfective,
noncalcific, nonischemic: most amenable to repair
Treatment of MR d.t. Ischemia or
Cardiomyopathy
• Maximal medical therapy: FIRST
• MVR (Mitral annular rings)
Key points...
• Patients with acute severe MR & hemodynamic
instability require rapid evaluation, aggressive
stabilization, & early valve operation
• Patients with acute severe MR & hemodynamic
stability: semielective surgery
• Indications for valve surgery in endocarditis:
progressive heart failure, resistance to antibiotics,
intracardiac abscess, recurrent systemic
embolization despite therapy
• Severe chronic MR & NYHA class III or IV, EF < 60 %,
End-systolic diameter > 45 mm, or end-systolic
volume > 50 mL/m2: Definite Surgery
Key points...
• Emerging indications for MV Replacement:
Flail leaflet, paroxysmal or recent A. Fib,
pulmonary HTN
• Impaired LV function: Valve repair preferred
• NO Repair in:
rheumatic, ischemic, endocarditis, anterior or
bileaflet prolapse, significant calcification
QUESTIONS
Question 20 of 264
Which one of the following statements about mitral valve prolapse is
incorrect?
A. The degree of echocardiographic thickening of the mitral
valve is related to long-term prognosis.
B. Clinical auscultatory phenomena as well as
echocardiographic documentation should be present for the
diagnosis of mitral valve prolapse.
C. Most symptoms in patients with the mitral valve prolapse
syndrome are related to the severity of mitral regurgitation.
D. Echocardiographic mitral valve prolapse may be seen in
normal individuals after volume depletion.
The correct answer is C.
Several clinical and autopsy studies have demonstrated that patients
with mitral valve prolapse and thick mitral valve leaflets are at high
risk for the development of complications. The diagnosis of mitral
valve prolapse as a general rule should be based on auscultatory and
confirmatory echocardiographic findings, and not on "soft"
echocardiographic or nonspecific auscultatory findings.
Echocardiographic mitral valve prolapse may be seen in normal
individuals after volume depletion or a decrease in intravascular
volume. Symptoms in patients with mitral valve prolapse may be
directly related to the severity of regurgitation. Certain patients with
mitral valve prolapse, however, may have symptoms related to
autonomic dysfunction (mitral valve prolapse syndrome). For the
diagnosis of mitral valve prolapse syndrome, mitral valve prolapse
should be present.
A 55-year-old African-American man is referred to you for evaluation of a murmur. The
murmur was first noted five years ago. He denies any symptoms, but admits that he has
always done little physical activity. He states that he no longer walks to the office, and does
not have to walk stairs to the third floor because there is an elevator. Family history: Both his
78-year-old father and his 48-year-old brother have heart murmurs, but are doing well.
Physical examination: BP 110/70 mm Hg, pulse 80/minute, respirations 15/minute. Neck
veins 5 cm. Carotid upstroke is normal without bruits. Lungs are clear to auscultation and
percussion. Point of maximal impulse is diffuse in the 5th intercostal space in the
midclavicular line and forceful. First and second heart sounds are normal. There is a grade
III/VI systolic murmur crescendo to the second sound, best heard at the apex, but radiating
well to the base. There are no S4 or S3 gallops and no other abnormalities.
Laboratory: Chest X-ray: Prominent LV, normal lung fields. ECG: LV hypertrophy by
voltage, no ST-T wave changes. Valve 2D echo-Doppler: Floppy mitral valve, severe
posterior leaflet prolapse, moderately severe mitral regurgitation (MR) with the jet directed
anterior-medially. LV end-diastolic diameter is 5.8 cm and LA diameter 4.5 cm. His EF is
estimated at 45-50%.
What is the most appropriate recommendation for treatment for this patient?
A. Follow medically with close observation and repeat echo if there is a clinical change.
B. Start enalapril and repeat echo in four months.
C. Send to surgery for mitral valve replacement.
D. Send to surgery for mitral valve repair.
E. Start long-acting nifedipine and repeat echo in one year.
The correct answer is D.
This man has MR and has the best pathology for successful
mitral valve repair. To require mitral replacement would be
very unusual with posterior leaflet prolapse and would be a
harder decision to make in this man who claims to be
asymptomatic, if it were necessary. Both options B and E
are incorrect because this man has an EF at the lower limits
of normal or mildly decreased, indicating a decreased
myocardial contractility in the presence of moderately
severe MR.
Question 51 of 264
A 36-year-old woman presents with sudden severe dyspnea. She had
mitral valve replacement five years ago with a St. Jude valve and ran
out of warfarin two weeks ago. Physical examination shows signs of
pulmonary edema and right heart failure. She is afebrile, BP is 130/86,
and pulse is 95 with sinus rhythm. TEE shows a large mass impairing
the mobility of one of the bileaflets.
The best initial management strategy would be which one of the
following?
A. Immediate valve replacement.
B. High-dose IV antibiotics.
C. A loading dose of heparin.
D. IV thrombolytic therapy.
E. IV enalapril.
The correct answer is D.
Acute valve thrombosis is a catastrophic complication of
prosthetic valve replacement and is almost always a result of
inadequate chronic anticoagulation. Because of the rarity of
this problem (0.2% per patient-year), there is not a great deal
of experience with any form of management. When clinical
suspicion is high, cinefluoroscopy or TEE should be done to
confirm the diagnosis. If thrombus is believed to be present
and the patient is hemodynamically stable, thrombolytic
therapy should be tried first followed by heparin, provided
there are no contraindications to this approach. If there are
contraindications to thrombolytics but not heparin, the latter
can be tried first. If there is no improvement in 48-72 hours or
if the patient decompensates, surgery is indicated.
Question 101 of 264
In which of the following diseases is pregnancy difficult, but
not highly risky to the mother and fetus?
A. Eisenmenger's syndrome.
B. Primary pulmonary hypertension.
C. Mitral prolapse with significant mitral regurgitation.
D. Prior peripartum cardiomyopathy with heart failure.
E. The Marfan syndrome with dilated aortic root.
The correct answer is C.
The CV system must be able to handle a doubling of cardiac output during
pregnancy. Thus, cardiopulmonary diseases that obstruct blood flow are
usually contraindications to pregnancy because both the mother and fetus get
inadequate blood flow. Thus, obstruction to pulmonary flow due to the
Eisenmenger reaction or primary pulmonary hypertension fits into this
category, but hypertrophic cardiomyopathy does not. The increased cardiac
output increases venous return to the left heart, resulting in LV enlargement
and less obstruction. In fact, during pregnancy, the murmur of hypertrophic
obstructive cardiomyopathy may lessen or even disappear, causing the
diagnosis to be missed.
Prior peripartum cardiomyopathy with heart failure is a contraindication to
pregnancy because of the high incidence of recurrent failure and death.
Hormonal changes during pregnancy alter vascular walls, making them more
distensible. This is a normal mechanism to adapt to higher cardiac output;
however, in the patient with the Marfan syndrome and an enlarged aortic
root, it can lead to increased wall stress and aortic rupture or dissection.
Question 153 of 264
A 52-year-old woman goes into acute pulmonary edema after an
auto accident. She has a mild concussion and bruises on her
upper body. ECG shows sinus tachycardia and nonspecific ST-T
wave changes. Physical exam shows BP 123/72, pulse 110
regular, diffuse pulmonary rales, a grade 2 early systolic murmur,
and a third heart sound.
What is the most likely diagnosis?
A. Ruptured papillary muscle.
B. AMI.
C. Cardiac contusion.
D. Noncardiogenic pulmonary edema.
E. Pulmonary contusion.
The correct answer is A.
Cardiac problems discovered following an auto accident raise
the question of whether the cardiac condition caused the
accident or vice versa. In this case, there is no cardiac history
preceding or during the accident, but only later. The ECG is not
suggestive of AMI, but it cannot be eliminated based on the
information given. The physical examination is consistent with
CHF (i.e., rales and third heart sound), and myocardial
contusion or ruptured papillary muscle could lead to pulmonary
edema. The early systolic murmur is characteristic of severe
acute mitral regurgitation due to papillary muscle rupture since
the resultant severe regurgitation rapidly eliminates the gradient
between the LV and atrium during systole, shortening what
would ordinarily be a holosystolic murmur. Thus, the best
answer is ruptured papillary muscle.
Question 163 of 264
A referring physician treating a patient with an inferior wall MI
calls you. The patient received thrombolytic therapy and seemed
to be stabilizing nicely. On the third day after the infarction, the
patient became acutely short of breath and is now in pulmonary
edema with a BP of 80 mm Hg systolic. On examination, the
jugular venous pressure is normal and auscultation of the heart
reveals no murmur or gallop. The ECG is unchanged.
The correct diagnosis in this case is:
A. Ruptured ventricular septum.
B. Papillary muscle rupture with severe mitral regurgitation.
C. Massive pulmonary embolism.
D. Infarct extension.
E. RV infarction.
The correct answer is B.
This is a typical presentation of a patient with inferior wall
MI and rupture of a papillary muscle several days after the
initial event. This complication can be treated with great
success if recognized and surgery to replace/repair the
valve is accomplished without delay. The lack of a murmur
is not unusual and probably relates to prompt equilibration
of LV and LA pressures. Involvement of the posterior
papillary muscle is more common as a result of a more
common single artery supplying this structure. Infarct
extension is unlikely in view of the unchanged ECG. An
RV infarction is unlikely in view of the normal jugular
venous pressure.
A 68-year-old Caucasian male has been a patient of yours for 10 years. He has had
insulin-treated diabetes mellitus for 14 years, known CAD with an MI 12 years ago, and
CABG 12 years ago. He follows his regimen of diet and exercises moderately, including
playing golf. In the past six months he has noted new bilateral ankle edema toward the
end of the day, as well as mild dyspnea on exertion. He denies chest discomfort. His
medications have been furosemide 40 mg daily, atorvastatin 40 mg daily, metoprolol
6.25 mg bid, isosorbide mononitrate 60 mg daily, ezetimibe 10 mg daily, aspirin 325 mg
daily, losartan/hydrochlorothiazide combination 100 mg/25 mg daily, dixogin 0.125 mg
qd, and rosiglitazone metformin combination 2/500 mg daily.
Laboratory work has shown total cholesterol 177 mg/dl, LDL cholesterol 77 mg/dl,
HDL cholesterol 48 mg/dl, and triglyceride 92 mg/dl. Renal, hepatic, and hematologic
functions were normal. Two-hour postprandial glucose was 134 mg/dl.
His ECG shows an old anterior MI and left anterior hemiblock; an echocardiogram
shows an LVEF of 0.38. The LA is mildly enlarged. There is moderate mitral
regurgitation. You should, as your first strategy:
A. Refer for mitral valve surgery.
B. Refer for biventricular pacing.
C. Increase his furosemide to 80 mg daily.
D. Begin spironolactone 25 mg daily.
E. Increase his losartan to 200 mg daily.
The correct answer is D.
The therapeutic issue is deciding what is maximum medical therapy in
this man with left- and now right-sided heart failure. There is little to
be gained by doubling his dose of losartan. While you may need to
increase his furosemide for comfort due to fluid retention, the best first
step is to add spironolactone, which should not only affect diuresis, but
contribute to improvement in LV systolic performance through its
renin-angiotensin effects. The device interventions may be considered
after maximum medical therapy has been achieved in reference to both
the number and dosage of the drugs. Mitral valve surgery is possible in
many patients with advanced failure, but in this case, the degree of
mitral regurgitation may lessen considerably with optimal medical
therapy, and additional evaluation including catheterization is needed
to make the decision if severe mitral regurgitation persists. He does not
currently meet accepted indications for ICD placement with his EF
above 35%.
Question 197 of 264
Which one of the following conditions is not considered a
contraindication to pregnancy?
A. Eisenmenger's syndrome.
B. Moderate primary pulmonary hypertension.
C. The Marfan syndrome with aortic root dilatation.
D. Moderately severe mitral regurgitation.
The correct answer is D.
The risk of pregnancy to the patient with pulmonary
hypertension is so great that pregnancy is not considered
an option. Similarly, the risk of aortic dissection is quite
high in those patients with the Marfan syndrome and aortic
root dilatation, so that pregnancy is contraindicated. So
long as LV function is normal, patients with mitral
regurgitation tolerate the hypervolemia of pregnancy.
Question 116 of 264
A 30-year-old black woman suddenly develops severe tachypnea and tachycardia
two days after open reduction of a comminuted fracture of the right femur. You are
called to see her in the recovery room. Physical exam: BP is 85/40 mm Hg. Pulse is
120/minute and irregular. Respiratory rate is 28/minute. Neck veins are 15 cm.
Lungs: No rales. Cardiac: Left anterior precordial lift. S2 widely split. A grade II/VI
short systolic ejection murmur is heard loudest at the third intercostal space left
sternal border. There is an S3 that increases with inspiration. Liver is palpable 35 cm
below the right costal margin. No pedal edema. Lab: Chest X-ray: Decreased
vascular markings in the right lower lobe and left upper lobe. Small pleural effusion
right costophrenic angle. ECG: Right axis deviation, RBBB, AF. Echo Doppler;
dilated poorly contracting RV. Dilated RA. Normal size LA and LV.
The Doppler jet of tricuspid regurgitation is most likely to be:
A. 1 m/sec.
B. 2 m/sec.
C. 3 m/sec.
D. 4 m/sec.
E. 5 m/sec.
The correct answer is C.
The case is that of a patient with a fracture who develops the classical
picture of acute massive pulmonary embolism. Such a patient with
extreme increase in RV afterload has no opportunity to hypertrophy to
compensate, dilates the RV, then fails. Such a ventricle cannot generate
systolic pressures much above 50 mm Hg. The tricuspid jet by the
modified Bernoulli equation:
P (m Hg) + 4x [Vcm/sec]2
Where P = the pressure drop across the tricuspid value
And V = the maximum jet velocity that can be used to estimate the
pulmonary artery systolic pressure
P + maximal RA pressure reflected by the jugular venous pressure =
estimated RV systolic
pressure, which in the absence of pulmonic infundibular and/or
valvular stenosis equals the
systolic pressure of the pulmonary artery.
Question 142 of 264
Abnormal septal motion can be seen in patients with each
of the following except:
A. CABG, postop.
B. A pacemaker.
C. LBBB.
D. Severe mitral regurgitation.
E. Constrictive pericarditis.
The correct answer is D.
Abnormal septal motion can be seen in CABG patients or
valve patients and is considered a "postop" septum. In
addition, the septum has abnormal motion when it is
electrically activated in an unusual fashion, as would be
the case for a patient with an LBBB or a pacemaker (when
the septum is activated right to left). Also, patients with
constrictive pericarditis typically have an abnormal septal
bounce. Patients with severe mitral regurgitation do not
have abnormal septal motion unless they have one of the
previously listed conditions (or severe pulmonary
hypertension or right-sided volume overload as well) in
addition to their mitral regurgitation.
Formulas for evaluation of MR
• RV = PISA x Velocity
(PISA determined as the aliasing velocity)
• PISA = 2 r2
• RV = ROA x VTI
• ROA = RV/VTI
[RV: Regurgitant Volume, PISA: Proximal
Isovelocity Surface Area, ROA: Regurgitant Orifice
Area or ERA: Effective Reugurgitant Area, VTI:
Velocity Time Integral]