Differential Diagnosis for Recent Onset of Sinus Rhythm with Wide QRS and Premature Ventricular Contractions

The patient's recent triple bypass surgery and medication regimen provide a complex background for the development of new cardiac rhythm disturbances. The following differential diagnoses are categorized based on their likelihood and potential impact:

• Single Most Likely Diagnosis

  • Hyperkalemia: Given the patient's use of Eliquis (an anticoagulant that can increase the risk of bleeding) and bumetanide (a loop diuretic that can cause electrolyte imbalances), along with the recent surgery, hyperkalemia is a plausible cause. Wide QRS complexes can be a sign of hyperkalemia, which can also predispose to premature ventricular contractions (PVCs).

• Other Likely Diagnoses

  • Digoxin Toxicity: The patient is on digoxin, and toxicity can cause a variety of arrhythmias, including those with wide QRS complexes and PVCs. Factors such as renal function and electrolyte balance can influence digoxin levels.
  • Electrolyte Imbalance (Hypokalemia, Hypomagnesemia): Besides hyperkalemia, other electrolyte disturbances can affect cardiac rhythm. Hypokalemia and hypomagnesemia, potentially exacerbated by diuretic use (bumetanide), can lead to arrhythmias.
  • Cardiac Ischemia or Infarction: Recent bypass surgery does not exclude the possibility of new or recurrent ischemia, which can cause arrhythmias, including those with wide QRS complexes and PVCs.

• Do Not Miss Diagnoses

  • Pulmonary Embolism: Although less likely to directly cause wide QRS complexes, a pulmonary embolism can lead to acute right heart strain, potentially resulting in arrhythmias. Given the patient's recent surgery and anticoagulation, this is a critical diagnosis not to miss.
  • Cardiac Tamponade: Post-surgical cardiac tamponade can cause arrhythmias among other symptoms. It's a life-threatening condition that requires immediate attention.

• Rare Diagnoses

  • Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): This condition can cause ventricular arrhythmias but would be less likely given the patient's presentation and recent surgical history.
  • Brugada Syndrome: Characterized by a specific pattern on the ECG that can include a wide QRS, but it's rare and less likely in this context without a suggestive family history or previous episodes.
  • Sarcoidosis or Other Infiltrative Cardiomyopathies: These conditions can cause arrhythmias but would be unusual without other systemic symptoms or a known history of such conditions.