Mitral regurgitation: Difference between revisions

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==Clinical Features==
==Clinical Features==
 
*Heart failure symptoms
*Atrial dilatation and [[atrial fibrillation]]
*[[Pulmonary hypertension]]
*Ischemic mitral incompetency, following [[myocardial infarction]] or [[LV aneurysm]]
**Most common mechanism of MR in developed countries
**Dysfunction of ventricular wall leads to papillary muscle dysfunction
**Posterior papillary muscle and supporting ventricular wall most commonly affected


==Differential Diagnosis==
==Differential Diagnosis==

Revision as of 03:52, 23 January 2017

Background

  • Annual incidence of degenerative Mitral Valve (MV) disease ~3% in industrialized countries causing MR[1]
  • Other etiologies of MR:
  • Criteria for MV repair[2]:
    • Development of NYHA class II symptoms
    • Deterioration in LV function
    • LV end systolic diameter < 4.5 cm with EF > 60% to protect LV function[3]
  • However, recent evidence suggests best outcomes of MV repair are in asymptomatic or minimally symptomatic patients selected for surgery soon after echo dx[4]

Clinical Features

  • Heart failure symptoms
  • Atrial dilatation and atrial fibrillation
  • Pulmonary hypertension
  • Ischemic mitral incompetency, following myocardial infarction or LV aneurysm
    • Most common mechanism of MR in developed countries
    • Dysfunction of ventricular wall leads to papillary muscle dysfunction
    • Posterior papillary muscle and supporting ventricular wall most commonly affected

Differential Diagnosis

Valvular Emergencies

Evaluation

  • Most common cause is papillary / chordae rupture after MI[5]
    • Day 2-7
  • MI, Endocarditis, Trauma
  • Severe dyspnea, tachycardia, pulmonary edema
  • Suspect if new-onset pulmonary edema + normal heart size
  • Cardiogenic shock may develop
  • S4, apical systolic murmur

Important to note; Clinical evaluation may be misleading leading to underestimation of mitral regurgitation severity. The classic holosystolic murmur can be much reduced in intensity. The tachycardia may make the murmur difficult to even appreciate. Even transthoracic echocardiography with color Doppler may be inadequate and underestimate the degree of regurgitation. [6]

Management[7]

Medical therapy is simply a measure to aid hemodynamic stabilization before surgery. The following measures may help to achieve hemodynamic stabilization before surgery.

  • Appropriate treatment if myocardial infarction to include cath or thrombolysis
  • Pulmonary edema
    • Oxygen
    • Nitrates and diuresis may improve filling pressures and treat edema
    • Early intubation for impending respiratory failure
  • Decrease afterload
    • Nitroprusside can be considered in normotensive patients to increase cardiac output and decrease MR
    • Intra aortic balloon pump may decrease afterload, increase forward cardiac output and reduce regurgitation
  • Inotropes
    • Dobutamine pressor of choice as alpha agonism and increased afterload minimal compared to beta agonism[8]
    • Do not alleviate tachycardia with beta-blockers as mild to mod tachycardia allows less time for LV to backfill


Consult Cards/CT Surgery!
  • Only real treatment is emergency surgery

See Also

References

  1. Kouchoukos NT. Problems in mitral valve replacement. In: Kirklin TW. eds. Advances in Cardiovascular Surgery. Grune & Stratton, New York,1973:205-16.
  2. Adams DH, Anyanwu AC. Seeking a higher standard for degenerative mitral valve repair: begin with etiology. J Thorac Cardiovasc Surg 2008;136:551-6.
  3. Mohan JC and Mohan V. Subclinical left ventricular systolic dysfunction in chronic mitral regurgitation and its potential impact on management: quo vadis? Indian Heart J. 2012 May; 64(3): 249–253.
  4. Anders S, Said S, Schulz F, et al. Mitral valve prolapse syndrome as cause of sudden death in young adults. Forensic Sci Int 2007;171:127-30
  5. Kosowsky JM: Infective Endocarditis and Valvular Heart Disease, in Marx JA, Hockberger RS, Walls RM, et al (eds): Emergency Medicine: Concepts and Clinical Practice, ed. 7. St. Louis, Mosby, Inc., 2010, (Ch) 81: p.1072-1074.
  6. Mitral Regurgitation, Ahmed MI, McGiffin DC, O'Rourke RA, Dell Italia LJ. Current Problems in Cardiology Volume 34, Issue 3, March 2009, Pages 93–136
  7. DiSandro D et al. Acute Mitral Regurgitation Treatment & Management. eMedicine. Dec 28, 2015. http://emedicine.medscape.com/article/758816-treatment.
  8. Sonoda M et al. Effects of Dobutamine Infusion on Mitral Regurgitation. Echocardiography. 1998 Jan;15(1):13-20.