Thank you Naina for presenting the case of an elderly man with 20 packyear smoking history presenting with acute onset of dyspnea and scant hemoptysis, found to have new onset A fib and L heart failure secondary to severe mitral regurgitation resulting from papillary muscle rupture!

Clinical Pearls

• In patients with severe mitral regurgitation (MR) and a normal L atrium size, think about acute causes of MR.  TEE is often indicated to better visualize the valve structure and determine need for operative intervention.
• MR can be caused by papillary muscle rupture, especially 3-7 days post MI.  Other etiologies of rupture include endocarditis and myxomatous valve degeneration.
• Patients with rupture present with acute onset hypotension, pulmonary edema, and a hyperactive precordium. A systolic murmur is not always present!
• Treatment:
  • Aggressive afterload reduction AND
  • Surgery (high mortality rate 20-25%)

Atrial Fribrillation

Categories:

• Paroxysmal (terminates within 7 days)
• Persistent (>7 days)
• Long-standing persistent (>1 year)

Differential for new onset A fib: (PIRATES!)

• Pulmonary (OSA, PE, COPD, PNA)
• Ischemia/infarction/CAD*
• Rheumatic heart disease/mitral regurgitation
• Alcohol/anemia (high output failure
• Thyrotoxicosis/toxins (stimulants)
• Electrolytes/endocarditis
• Sepsis/sick sinus syndrome
• Other: HTN*, congenital heart disease, previous cardiac surgery, viral infections

* Most common causes in the US.

Treatment:

• Rate control (preferred method based on AFFIRM and RACE trials)
  • Beta blockers
  • Calcium channel blockers ⇒ contraindicated in decompensated heart failure
  • Digoxin ⇒ avoid use in renal failure, hypokalemia, hypomagnesemia, or hypercalcemia
  • Amiodarone
• Rhythm control
  • Methods:
    • Chemical (~30% success rate)
      • Class III (amiodarone, sotalol, ibutilide)
    • Electrical (synchronized to QRS, ~80% success rate)
  • Preferred modality in
    • Hemodynamically unstable
    • Young patient (age <65) or good functional status
    • Early in natural history of disease
    • Failure of rate control agents
    • Heart failure

Complications post MI:

Figure from article by Reed et al. Lancet. 2017.

Papillary muscle rupture:

• Posteromedial muscle is 6-12x more likely because blood supply is through PDA only. Anterolateral muscle receives dual supply from LAD and LCx.
• Clinical presentation
  • Acute onset hypotension, pulmonary edema
  • Hyperactive precordium
  • Mid, late, or holosystolic murmur with widespread radiation (though many have no murmur!)
  • Diagnosis requires TTE/TEE
  • Treatment:
    • Aggressive afterload reduction
    • Urgent/emergent surgical intervention (20-25% mortality)