Atrial Fibrillation

Epidemiology

  • xxx

Etiology

  • Ruptured Sinus of Valsalva Aneurysm (see [[Sinus of Valsalva Aneurysm]])

Presentations

  • xxx

Clinical

(may be asymptomatic)

  • Hypotension (see Hypotension): particularly with rapid ventricular response
  • Palpitations
  • Chest Pain

New-Onset Atial Fibrillation in Sepsis

  • Epidemiology: 6-20% of patients with severe sepsis develop new-onset AF
  • Clinical
    • Patients with new-onset AF and severe sepsis are at a 4-fold increased risk of in-hospital CVA and a 7% increased risk of death, as compared with patients with no AF and patients with preexisting AF
      • Possible Mechanisms for Increased Risk of CVA in New-Onset AF in Severe Sepsis: new-onset AF might just be a marker for the sickest patients with greatest inherent CVA risk, sepsis itself might result in an increased risk for CVA (by hemodynamic collapse, coagulopathy, or systemic inflammation), or new-onset AF might be a source of cardio-embolic CVA
    • Patients with severe sepsis had a 6-fold increased risk of in-hospital CVA, as compared with hospitalized patients without severe sepsis
    • Patients with severe sepsis and preexisting AF did not have an increased CVA risk, as compared with patients without AF

      [Incident Stroke and Mortality Associated With New-Onset Atrial Fibrillation in Patients Hospitalized With Severe Sepsis JAMA 2011;306(20):doi:10.1001/jama.2011.1615]


Treatment

Rate Control Agents

  • Digoxin
  • Calcium Channel Blockers with AV Nodal Blocking Activity: diltiazem, verapamil
  • Beta Blockers: metoprolol, atenolol, etc

Anticoagulation

  • ACCP recommends ASA for pts 60-75 y/o (if no risk factors)
  • ACCP recommends coumadin (INR 2-3) for pts >60 y/o with heart disease or diabetes and in all pts >75 y/o
  • Dabigatran (Pradaxa) (See [[Dabigatran]])

Cardioversion

  • AF <48 hrs: synchronized conversion (120-200 J) without anticoagulation
  • AF >48 hrs: anticoagulation x 2 wks, then conversion (if TEE shows no clots, conversion is safe without anticoagulation).
  • Risk Factors for Recurrent AF After Conversion: age and gender are not risk factors for recurrence
    • EF <40%
    • LA >3.9 cm (long axis)
  • Pharmacologic Cardioversion
    • Dronedarone: significantly reduces the risk for hospitalization due to cardiovascular events or death in patients with paroxysmal or persistent AF or flutter
      • Decreases death rate from cardiac arrhythmia
      • Side Effects: increased creatinine, without change in renal function (due to partial inhibition of tubular organic cation transporters), low incidence of thyroid and pulmonary toxicity

Treatment of Concomitant OSA (if present)

  • Use of CPAP (>4 hrs/nt) in OSA patients with AF has been shown to decrease risk of recurrent AF after cardioversion (42% recurrence rate vs. 82% recurrence rate):
  • May be related to effects of OSA on nocturnal hypoxemia, hypercapnia, sympathetic drive, and changes in intrathoracic pressure

References

  • Hohnloser SH, et al. Effect of dronedarone on cardiovascular events in atrial fibrillation. N Engl J Med 2009;360:668-678
  • Zareba KM. Dronedarone: a new antiarrhythmic agent. Drugs Today 2006;42:75-86
  • Incident Stroke and Mortality Associated With New-Onset Atrial Fibrillation in Patients Hospitalized With Severe Sepsis JAMA 2011;306(20):doi:10.1001/jama.2011.1615