Smoldering myeloma and amyloidosis and the heart

There's not much to go by here so I dropped your title in the Claude AI app and here's what came out.

This is general information and treatment standards change, so your hematology and cardiology teams are the right source for specifics.

The key point: smoldering myeloma (SMM) by definition has no organ damage. If amyloid is found in the heart, the diagnosis is no longer "just smoldering." It is AL amyloidosis (with an underlying plasma cell disorder), and it is usually treated promptly.
How they connect
Both come from abnormal plasma cells. In AL amyloidosis, the clone makes light chains that misfold and deposit in organs, most often the heart and kidneys.
Someone can have SMM and AL amyloidosis at the same time. The amyloid, not the SMM, then drives treatment.
Not all cardiac amyloid is AL. Wild-type or hereditary transthyretin amyloid (ATTR) is common in older adults, and a monoclonal protein can be an incidental bystander. The amyloid type has to be confirmed by biopsy with mass spectrometry or typing, not assumed from the blood tests.
Heart clues that prompt a workup
Shortness of breath, swelling, fatigue, lightheadedness on standing, fainting, or arrhythmias
Thick heart walls on echo but low voltage on ECG
Persistently raised NT-proBNP or troponin
Non-heart clues: carpal tunnel, neuropathy, enlarged tongue, easy bruising around the eyes, protein in the urine
Typical evaluation: NT-proBNP and troponin, echo with strain imaging, cardiac MRI, serum free light chains and immunofixation, and a tissue biopsy (fat pad, bone marrow, or heart) with amyloid typing.
Treatment: AL cardiac amyloidosis is generally treated with plasma cell–directed therapy, commonly daratumumab-based regimens, along with careful heart failure management. Cardiac stage strongly affects outlook, so early diagnosis matters. Treatment for ATTR is different, which is why typing matters.

I have SMM and my doctors are following the eval protocols listed here. I am scheduled for a cardiac MRI and a troponin blood test. I had an echo for possible mitral valve relapse (ultimately determined I did not have) and my new cardiologist read report which noted an area of thickening in heart which prompted this testing. So nice to have an excellent doctor who is proactive.