to the bedside…

• Rate.
  • 134 bpm
• Rhythm.
  • Regular.
  • No obvious P’s.
• Axis.
  • Markedly rightward [ +156* ]
• Intervals.
  • PR – n/a
  • QRS – 90msec
  • QTc ~ 420msec
• Additional.
  • RBBB pattern (< 120msec therefore incomplete)
  • Right ventricular hypertrophy w/ RV strain pattern
    • very large R-wave (V1) [>>7mm] + R/S >>1
    • deep S-wave [V6] + R/S <1.
    • ST depression + TWI (V1-3)
  • ?Flutter wave V2.

Interpretation.

• Young female w/ chest pain.
• Narrow complex tachycardia w/out clear P-waves
  • is this SVT or Atrial flutter ??
• Incomplete RBBB w/ right ventricular hypertrophy & strain pattern.

• Differential Dx:
  • ?Pulmonary embolism with right-heart strain
  • ?chronic lung disease w/ cor pulmonale or pulmonary hypertension
  • ?underlying congenital heart disease

Your patient looks very well.

• Alert & speaking full sentences.
• Observations:
  • SaO2 100% on room air.
  • P 134. BP 126/-. RR 20.
  • Afebrile.
• Obvious old, well-healed midline-sternotomy scar.
• Clear chest.

“It’s ok Doc, I’ve had this before” she tells you.

Her background:

• Transposition of Great Vessels.
• Mustard procedure (see below).
• Recurrent atrial flutter.
• Previous electrophysiology studies  [multiple re-entry circuits identified and ablated].

Atrial flutter with right ventricular hypertrophy secondary to congenital heart disease.

• We discuss the pro’s & con’s of  electrical vs chemical cardioversion.
• Electrical cardioversion is chosen.
  • Ketofol (30/30mg)
  • 50J synchronised shock…

• She is discharged a few hours later !!