Secondary Mitral Regurgitation

Question 1

What is the estimated prevalence of mitral regurgitation (MR) in the United States?

Answer 1

1.7% overall; increases to 9.3% in those >75 years of age

MR is one of the most common valvular heart disorders.

Question 2

How is primary mitral regurgitation classified?

Answer 2

Due to a structural or degenerative abnormality of the mitral valve, chordae tendineae, papillary muscles, or mitral annulus.

Question 3

What characterizes secondary or functional mitral regurgitation?

Answer 3

Occurs in the absence of organic mitral valve disease, usually due to left ventricular dysfunction.

Question 4

Is secondary MR more common than primary MR?

Answer 4

Yes, secondary MR is more common than primary MR.

Question 5

What is the prognosis associated with secondary MR?

Answer 5

Worse prognosis primarily related to the severity of the underlying left ventricular dysfunction.

Question 6

What structural changes can lead to secondary MR?

Answer 6

LV dilation due to ischemic or nonischemic cardiomyopathy can impair leaflet coaptation.

Question 7

What are the two types of mitral regurgitation?

Answer 7

Ischemic and nonischemic.

Question 8

What usually causes ischemic mitral regurgitation?

Answer 8

LV remodeling after myocardial infarction causing papillary muscle displacement.

Question 9

What conditions can lead to nonischemic mitral regurgitation?

Answer 9

Hypertension or idiopathic dilated cardiomyopathy.

Question 10

What is the association of secondary MR severity with clinical outcomes?

Answer 10

Associated with all-cause mortality and heart failure hospitalization.

Question 11

What echocardiographic findings are used to classify the severity of MR?

Answer 11

Mild, moderate, or severe.

Question 12

What is the effective regurgitant orifice area (EROA) for severe primary MR?

Answer 12

≥40 mm².

Question 13

What is the effective regurgitant orifice area (EROA) for severe secondary MR?

Answer 13

≥20 mm².

Question 14

What is the role of exercise echocardiography in assessing MR?

Answer 14

Useful when symptoms appear disproportionate to resting MR severity.

Question 15

What are some predictors of failed MitraClip placement?

Answer 15

• Greater EROA * Baseline transmitral pressure gradient ≥4 mm².

Question 16

What pharmacological treatments may help patients with LV dysfunction and secondary MR?

Answer 16

• Carvedilol * Metoprolol * ACE inhibitors.

Question 17

What is the goal of therapy for secondary MR?

Answer 17

To relieve symptoms, improve quality of life, reduce HF hospitalizations, and potentially improve survival.

Question 18

What is cardiac resynchronization therapy (CRT) recommended for?

Answer 18

Selected HF patients with LV dyssynchrony.

Question 19

What effect does CRT have on secondary MR?

Answer 19

Overall MR severity decreases with restoration of synchronous ventricular contraction.

Question 20

True or False: The predictive value of exercise echocardiography is perfect.

Answer 20

False.

Question 21

Fill in the blank: The severity of secondary MR can vary during the _______.

Answer 21

cardiac cycle.

Question 22

What was the sample size of the InSync Randomized Clinical Evaluation trial?

Answer 22

450 patients

Question 23

What functional class of heart failure patients was included in the InSync trial?

Answer 23

NYHA functional class III/IV

Question 24

What were the key outcomes of CRT in the InSync trial?

Answer 24

Reductions in LV end-diastolic and end-systolic volumes, improved LVEF, sustained reductions in MR

Question 25

In the study of 63 HF patients with moderate to severe MR, what percentage improved by ≥1 grade?

Answer 25

43%

Question 26

What is the association between improvement of severe secondary MR and prognosis?

Answer 26

Better prognosis

Question 27

What percentage of patients experience improvement after CRT for severe secondary MR?

Answer 27

No more than one-half

Question 28

What does secondary MR indicate?

Answer 28

It is secondary to disease of the LV, not of the valve itself

Question 29

How does heart failure associated with secondary MR compare to heart failure without MR?

Answer 29

Worse prognosis

Question 30

What does the MitraClip do?

Answer 30

Clips the mitral leaflets together, reducing MR

Question 31

What were the findings of the Mitra-FR trial regarding MitraClip?

Answer 31

No reduction in repeated hospitalizations or mortality

Question 32

What were the findings of the COAPT trial regarding MitraClip?

Answer 32

Reduced rehospitalizations and mortality in patients with severe MR and modest LV dilation

Question 33

What is now FDA approved for the treatment of severe symptomatic secondary MR?

Answer 33

MitraClip

Question 34

What is the role of guideline-directed medical therapy in patients with moderate or severe secondary MR?

Answer 34

Sometimes effective in reducing secondary MR and improving prognosis

Question 35

What is less clear regarding treatment options for persistent severe secondary MR?

Answer 35

The appropriate role of surgical and transcatheter interventions

Question 36

What is a key factor in making treatment decisions for secondary MR?

Answer 36

Accurate assessment of MR severity

Question 37

True or False: Surgical approaches to secondary MR have shown improved survival compared to medical therapy.

Answer 37

False

Question 38

Fill in the blank: The MitraClip creates a _______ orifice, reducing MR.

Answer 38

figure of 8