Differential Diagnosis for EF 71% with Low Risk PET Myocardial Perfusion Study
Single Most Likely Diagnosis
- Microvascular Coronary Disease: This condition is characterized by reduced flow reserve in the coronary microvasculature, which can lead to ischemia during stress or increased demand, despite the absence of significant epicardial coronary artery disease. The reduced flow reserve in the circumflex distribution and the minor fixed basal lateral defect on the PET myocardial perfusion study support this diagnosis.
Other Likely Diagnoses
- Coronary Artery Disease with Non-Obstructive Lesions: Although the PET study is low risk for significant ischemia, the presence of a minor fixed defect and reduced flow reserve could indicate non-obstructive coronary artery disease that does not significantly impair blood flow at rest but may during stress.
- Cardiac Syndrome X: This condition presents with chest pain and evidence of ischemia on diagnostic tests, but without obstructive coronary artery disease. The reduced flow reserve and minor perfusion defect could be consistent with this diagnosis.
Do Not Miss Diagnoses
- Coronary Artery Vasospasm (Prinzmetal’s Angina): Although less likely, this condition can cause reduced flow reserve and ischemia without significant fixed obstructive lesions. It is crucial to consider due to its potential for severe and unpredictable ischemic episodes.
- Aortic Stenosis: Severe aortic stenosis can lead to reduced coronary flow reserve due to increased left ventricular pressure and wall stress. Although the EF is preserved, significant aortic stenosis could explain the findings and is a critical diagnosis not to miss due to its implications for treatment and prognosis.
Rare Diagnoses
- Cardiac Sarcoidosis: This condition can cause patchy myocardial inflammation and fibrosis, potentially leading to perfusion defects and reduced flow reserve. It is less common but should be considered, especially if other systemic symptoms or diagnostic findings suggestive of sarcoidosis are present.
- Cardiac Amyloidosis: Amyloid deposition in the heart can lead to restrictive cardiomyopathy and potentially affect coronary flow reserve. Although rare, it's an important consideration in the differential diagnosis due to its distinct treatment and prognosis.