[Cardiac amyloidosis--cardiovascular magnetic resonance imaging as a valuable diagnostic tool]

A 90-year-old man presented at the emergency room with symptoms of severe heart failure. A few weeks earlier he had been seen with the same symptoms at another hospital where the diagnosis of severe aortic valve stenosis had been made and aortic valve replacement was recommended. However, the patient did not consent to surgery and was discharged after medical treatment.

Echocardiography demonstrated global hypertrophy, pronounced at the ventricular septum. Interestingly the transaortic pressure gradient was only slightly elevated, revealing mild aortic stenosis. Thus, for work-up of discrepancies between the recent and previous (in the other hospital) exam results, cardiac magnetic resonance imaging (CMR) was performed.

CMR planimetry confirmed that the aortic stenosis was only mild. However, contrast CMR revealed typical circular subendocardial late gadolinium enhancement in the entire left ventricle, which is typically seen in cardiac amyloidosis. This diagnosis was confirmed by endomyocardial biopsy revealing transthyretin-type amyloidosis.

Recompensation was achieved using diuretics and usual heart failure medication. Unfortunately, there is no causal treatment for transthyretin-type amyloidosis. However, the unnecessary aortic valve replacement surgery could be avoided.

CMR is capable to precisely assess the aortic valve area even in cases with discrepant findings by other techniques. In addition, contrast CMR allows noninasive detection of myocardial abnormalities in living patients. Based on the pattern of contrast enhancement, differentiation between etiologies is possible.