Vancouver IM LMR

In today’s noon report, we work through the case of a 66M, no known medical history, who presents with severe hypoxemia after 2 weeks of SOBOE and an episode of chest pain 2 days prior. Initial ddx included acute heart failure exacerbation vs pneumosepsis.

Eventually, he was found to have cardiogenic pulmonary edema due to acute MR from a ruptured posterior papillary muscle after missed MI!

See the didactic slide deck (including ECG and echo) here.

Key takeaways:

• Differential diagnosis for acute (flash) pulmonary edema:
  • Increased preload (volume overload, acute AR or MR)
  • Decreased contractility (MI, new onset tachyarrhythmia)
  • Increased afterload (HTN, e.g. in renovascular HTN)

• Acute MR in native valves:
  • Ischemic usually from papillary muscle rupture/ displacement
  • Nonischemic usually from ruptured mitral chordae tendinae (flail leaflet) due to:
    • Myxomatous disease (MVP)
    • Infective endocarditis
    • Rheumatic heart disease
    • Spontaneous rupture, trauma
• Clinical manifestations:
  • Decrescendo early systolic murmur heard at LSB or base is classic; if the jet is posteriorly ejected the murmur may be easier heard at the back
  • However, acute MR may be silent – absence of systolic murmur does not reliably rule out MR
  • In a minority of cases can result in asymmetric pulmonary edema which can mimic lobar pneumonia!

• Management
  • Medical stabilization
    • Reduce afterload (target lowest BP needed to perfuse organs) – vasodilators
    • Reduce preload – diuretics, venodilators, NIPPV
    • Maintain MAP (inotropes e.g. low dose epinephrine, dobutamine)
  • Definitive management requires intervention (interventional cardiology or cardiothoracic surgery) for mitral valve repair/ replacement!