Differential Diagnosis for 80-year-old Male with Atrial Fibrillation and Congestive Heart Failure

• Single most likely diagnosis:

  • Atrial fibrillation with rapid ventricular response (RVR) exacerbating congestive heart failure. This is likely because the patient's presentation of atrial fibrillation with RVR and symptoms of congestive heart failure (such as shortness of breath, possibly fatigue, and signs of fluid overload) are classic for this condition. The absence of chest pain and ST changes on the ECG further supports this diagnosis, as these findings are more typical of acute coronary syndrome (ACS).

• Other Likely diagnoses:

  • Acute coronary syndrome (ACS) with atypical presentation: Although the patient does not have chest pain or ST changes, the slightly elevated cTnI (0.22 ng/ml) could suggest some myocardial injury, which might be seen in ACS, especially in the context of atrial fibrillation and RVR.
  • Cardiomyopathy: Given the congestive heart failure, it's possible that the patient has an underlying cardiomyopathy (dilated, hypertrophic, etc.) that is contributing to his symptoms and atrial fibrillation.

• Do Not Miss diagnoses:

  • Pulmonary embolism (PE): Although less likely, PE can cause atrial fibrillation, RVR, and signs of heart failure, and it is crucial not to miss this diagnosis due to its high mortality rate if untreated.
  • Cardiac tamponade: This condition can cause heart failure symptoms and atrial fibrillation and is a medical emergency.
  • Aortic dissection: While typically presenting with severe chest pain, it's essential not to miss this diagnosis, as it can be catastrophic if not promptly treated.

• Rare diagnoses:

  • Thyrotoxicosis: Atrial fibrillation can be a presentation of thyrotoxicosis, especially in elderly patients, and it can also contribute to congestive heart failure.
  • Cardiac sarcoidosis: This condition can cause heart failure, atrial fibrillation, and might have a varied presentation, including elevated troponins due to myocardial involvement.