Elderly Female with recently Dx MM

[JNUS]

CLINICAL BACKGROUND

A 68-year-old woman recently diagnosed with multiple myeloma presents to her GP with progressively increasing breathlessness, exercise intolerance and ankle swelling. On examination, there is bilateral pitting leg oedema to her thighs, ascites and raised JVP. The apical impulse is impalpable. An ECG shows diffusely diminished voltage. Chest X-ray is normal and the echocardiogram shows small thick ventricles and dilated atria with a thickened interatrial septum. The ventricular myocardium has a granular sparkling texture on echo, and minimal fluid in the pericardial space is noted.

What is the most likely diagnosis?

[bharat]

well Diff. Diagnosis are as follows:-
1)Right Heart failure :- Suggestive findings are:-progressively increasing breathlessness, exercise intolerance and ankle swelling. On examination, there is bilateral pitting leg oedema to her thighs, ascites and raised JVP.
2)Restrictive-Cardiomyopathy:_ supporting features are:-
a)s/s of Heart failure(Rt.)
b)exercise intolerence
c)ECG show diffusely diminished voltage. & Chest X-ray is normal
d)echo shows:- large atria, thickened ventricular wall
"The ventricular myocardium has a granular sparkling texture on echo"---i think amyloidosis should not be fibrosis/heochromatomasis
so i think this is restrictive cardiomyopathy.
3) but still no clacification is seen on CXR i like to include Constrictive pericarditis also as a diffrential diagnosis coz. PE suggesting:_ ankle swelling,The apical impulse is impalpable.
An ECG shows diffusely diminished voltage , echocardiogram shows small thick ventricles