A Fib / A Flutter

Atrial Fibrillation: Progress Note should include the following components
  • AF: Paroxysmal / Persistent / Longstanding persistent / Permanent - RVR +/- - For Stroke Prevention:  Calculate Risk of  Stroke (CHADS2-VaSC) and the risk of Bleeding on Anticoagulation (HAS BLED) - Rate vs Rhythm Control Strategy 
  • New onset A fib - Look for cause (PE, OSA, HTN, Structural heart disease, hyperthyroidism) - Also, decide when to ablate by cardioversion for new onset A Fib

Appreciate AF definition; Also, appreciate Non-Valvular AF 
A fib duration of > 6 min or > 6 hr of atrial fib causes increased risk of stroke. Any duration a fib in a high risk chadvasc patient should be treated , but no data to suggest if duration < 6 min

Patient with A fib and HCM are at high risk of stroke, and should be anti-coagualted even though low CHADS VaSC of 0. HCM is treated like non-valvular a fib. 
GI bleeding due to embolic ischemia is common. Such patients need to be on oral anticoagulation. 
CHAD VaSC of 1 in a women due to gender is to be disregarded. It counts if other risk factor is present.

Anticoagulation In Atrial Fibrillation

Warfarin reduces the risk of stroke by 64 %
NOAC vs warfarin in A fib
  • No data of NOAC for Cr Cl < 30
  • NOAC not indicated for ESRD 
  • If INR is at goal at >70% of the time, warfarin is effective in reducing the risk of stroke. In all the studies of NOAC vs Warfarin for A Fib, INR was at goal in 50-68%. Non-had >70% 
  • On warfarin, unable to reach the therapeutic INR is not same as non-compliant.
    • Genetic factors??
    • Also, patient on NOAC are not necessarily compliant 
Watchman is reasonable in selected patients
  • Not all patients with A fib are from atrial appendages. .... % are. 
  • Appropriate rationale is used
    • Eg. Patient has had recurrent fall that is getting worse. You can put watchman, and continue anti-coat for 45 days after implant until watchman is endothelised, then we can stop anti-coag. 

Dosing of Anticoagulation and Dose adjustment in Renal Failure:

Rate Control: Common medications and dosing and Selection 

Rhythm Control - Selection of Strategy

Important Additional Concepts in Atrial Fibrillation

A Flutter. 2:1 Conduction. 

A flutter: 4:1 conduction
Discordant p wave polarity between V1 and Inferior leads: Hence, is a typical flutter 
Counterclockwise: Negative in V1 (positive in inferior leads)

Same patient with Variable conduction giving irregular heart rate 

NOAC in Non-Valvular Atrial Fibrillation
Case Discussion: 
37 yo F is seen 1 week after C-section for 6 hrs of SOB with palpitation. Found to have A fib with RVR. HTN diagnosed in third trimester. ECHO shows LVH and LA dilatation. How would you manage this patient?
  • For RVR: Diltiazem drip
  • Stroke Prevention: Anti-coag for 1 month after cardioversion
  • Rhythm / Rate Control : Cardioversion
  • Etiology: HTN, Sleep Apnea Screeing