Differential Diagnosis for 70-year-old Male with Repeated Syncope and Collapse

Given the cardiac ECHO findings and the patient's symptoms of repeated syncope and collapse, the following differential diagnoses are considered:

• Single Most Likely Diagnosis

  • Hypertrophic Cardiomyopathy (HCM) with Outflow Tract Obstruction: Although the ECHO shows only mildly increased left ventricular wall thickness, which might not be typical for HCM, the presence of syncope, a normal ejection fraction, and the absence of other clear causes of syncope (like significant valvular disease or reduced systolic function) make this a consideration. The mildly increased wall thickness could be an early sign or a variant of HCM.

• Other Likely Diagnoses

  • Aortic Stenosis: Despite the ECHO not mentioning aortic valve disease, aortic stenosis can cause syncope due to obstructed outflow. It's possible that the stenosis is not severe enough to be detected or was missed.
  • Cardiac Conduction System Disease (e.g., Sick Sinus Syndrome, AV Block): These conditions can lead to syncope due to inadequate cardiac output during episodes of bradycardia or asystole. The normal ECHO does not rule out conduction system diseases.
  • Vasovagal Syncope: A common cause of syncope, especially in older adults, which might not have a clear cardiac cause identifiable on ECHO.

• Do Not Miss Diagnoses

  • Aortic Dissection: Although the ECHO does not directly suggest this, aortic dissection can cause syncope and is a life-threatening condition that requires immediate diagnosis and treatment. It might not always be evident on a standard ECHO.
  • Pulmonary Embolism: Can cause syncope due to acute right ventricular overload. The ECHO shows normal right ventricular function, but this does not rule out a recent or small pulmonary embolism.
  • Cardiac Tumor (e.g., Myxoma): Although rare, cardiac tumors can cause obstructive symptoms and syncope. The ECHO did not mention any masses, but it's essential to consider given the symptom of syncope.

• Rare Diagnoses

  • Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC): Given the normal right ventricular function and dimensions, this is less likely, but it can cause syncope due to ventricular arrhythmias.
  • Left Atrial Myxoma: Although the left atrial dimension is normal, a myxoma could be present and cause intermittent obstruction leading to syncope.
  • Takotsubo Cardiomyopathy: Typically presents with acute left ventricular dysfunction, which is not seen here, but could be considered if there were recent stressors and the ECHO was done after recovery of systolic function.