Differential Diagnosis
- Single most likely diagnosis
- Cardiac Amyloidosis: The patient's CMR showing a large amount of LGE at the mid-wall of the inferior and lateral wall, and subendocardial throughout the anterior wall, is highly suggestive of an infiltrative process like cardiac amyloidosis. The patient's age, history of CAD, and improvement in EF also support this diagnosis.
- Other Likely diagnoses
- Light Chain Amyloidosis (AL Amyloidosis): The patient's lab results showing an abnormal free kappa/lambda ratio and a faint band in IgM kappa on IFE suggest the possibility of AL amyloidosis, although the ratio is not significantly elevated.
- Monoclonal Gammopathy of Undetermined Significance (MGUS): The patient's lab results showing a faint band in IgM kappa and elevated total IgG and IgM levels could be indicative of MGUS, which can be a precursor to AL amyloidosis.
- Do Not Miss
- Myocardial Infarction: Given the patient's history of CAD and NSTEMI, it is essential to consider the possibility of another myocardial infarction, especially if the patient presents with symptoms such as chest pain or shortness of breath.
- Hypertrophic Cardiomyopathy: Although less likely, hypertrophic cardiomyopathy could present with similar CMR findings, and it is crucial to consider this diagnosis to avoid missing a potentially deadly condition.
- Rare diagnoses
- Transthyretin Amyloidosis (ATTR): This is a rare form of amyloidosis that can present with similar CMR findings, although it is less likely given the patient's lab results.
- Sarcoidosis: This condition can cause infiltrative cardiomyopathy and present with similar CMR findings, although it is less likely given the patient's age and lack of other symptoms suggestive of sarcoidosis.
- Fabry Disease: This is a rare genetic disorder that can cause infiltrative cardiomyopathy, although it is less likely given the patient's age and lack of other symptoms suggestive of Fabry disease.