High-Yield CMR for Cardiac Amyloidosis

Summary: Looking beyond non-specific LV hypertrophy, confirm post-contrast timing before diagnosing “myocardium-first” darkening.

Heart of Darkness: Noting myocardial involvement, characterizing LGE, measuring disease extent parametrically—CMR creates clarity for cardiac amyloidosis. Classically, Dr. Matthew D. Cham said at ARRS26, cardiac amyloidosis presents with concentric LV hypertrophy on initial cine or SSFP imaging.

• The Catch? Concentric LV hypertrophy is highly non-specific and easily mimics commoners (e.g., systemic hypertension).
• Cham’s Solution: Contrast kinetics vis-à-vis specialized sequence.

TI Scout: The Look-Locker sequence provides key contrast kinetics by observing the order of tissue nulling:

• Normal: Cavity nulls first; myocardium nullification afterwards.
• Amyloidosis: Myocardium nulls first, then the lumen darkens.

Patchy Involvement: When amyloid deposition is focal or non-uniform, distinguishing normal from diseased becomes quite challenging.

• And if a tech accidentally runs Look-Locker before contrast injection, healthy myocardium will null first—creating false-positive “amyloid pattern” in otherwise normal patient.