IMAGING IN CARDIAC AMYLOIDOSIS ; TRENDS IN DIAGNOSIS AND GUIDING THERAPY

Transcription

1 IMAGING IN CARDIAC AMYLOIDOSIS ; TRENDS IN DIAGNOSIS AND GUIDING THERAPY Mohamed Abo Mandour, MD. Al-Azhar University Cardiac amyloidosis is an under appreciated cause of HF The bottom line pathologic mechanism is extracellular deposition of fibrillary proteins However, there are at least three different pathophysiologic substrates and types of cardiac amyloidosis I) AL cardiac amyloid Immunoglobulin light chains Plasma cells in the bone marrow Treatment involves chemotherapeutics II) Transthyretin (ATTR) related cardiac amyloidosis misfolded monomers or diamers of tetrameric transthyretin protein (TTR) o Mutant TTR (ATTRm familial amyloid cardiomyopathy) owild type TTR (ATTRwt, also known as senile systemic amyloidosis, SSA) 1

2 Cardiac Amyloidosis is a relatively common disease: The most common ATTRm allele is the valine to isoleucine substitution at position 122 (V122I) In approximately 3.5% of African Americans ATTRwt cardiomyopathy found at autopsy in 30% of patients with HFpEF 75 years Endomyocardial biopsy is the gold standard for definitive diagnosis (with either immunohistochemistry or mass spectroscopy) Limitations : Limited availability and needs particular expertise Extent or distribution of disease Progression or response to treatment May lead to delayed care Many older adults are reluctant to undergo invasive procedures 2

3 Therefore, the clinical need for a non-invasive imaging modality is a must To establish diagnosis Differentiate AL from ATTR subtypes Quantify the extent of amyloid infiltration Monitor disease progression Monitor response to treatment 3

4 CARDIAC AMYLOIDOSIS UPDATES 4

5 NUCLEAR IMAGING AL ATTR Semi-quantitative analysis of 99mTc-PYP uptake In a negative (A) and positive subject (B) are shown 1 hour after radiotracer infusion. ROI circles are depicted in red and the contralateral comparison circle is depicted in blue Bokhari et al. Circ

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7 Value of SPECT and SPECT/CT 7

8 Monitoring of therapy o A case of systemic AL amyloidosis with advanced cardiac involvement. o The patient was treated with a bortezomib-based regime with a complete hematological response. o A = positive 99mTc-DPD scan at baseline with grade 3 cardiac uptake. o B = Follow up 99mTc-DPD scan after 3 years, with marked reduction in the cardiac uptake. Wechalekar, JNC, 2016 Wechalekar, JNC,

9 Rest F-18 florbetapir PET images showing diffuse biventricular uptake of radiotracer in a patient with cardiac amyloidosis. Falk et al. Circ Cardiovasc Imaging. 2014;7:

10 Falk et al. Circ Cardiovasc Imaging. 2014;7: ECHOCARDIOGRAPHY IN AMYLOIDOSIS 10

11 Salinaro et al. Eur HJ-cardiovascular imaging,

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13 CMR IN AMYLOIDOSIS 13

14 o Abnormal diastolic function o Biatrial enlargement o Concentric thickening of the left ventricle o Reduced systolic function of both ventricles Late enhancement image shows enhancement over the entire subendocardial circumference Variably extending into the neighboring myocardium Sometimes it is difficult to find the optimal inversion time for nulling the normal myocardium Falk et al. Circ cardiovasc Imaging 2014; 7:

15 AL Vs. ATTR by CMR Markedly elevated myocardial T1 time in the AL cardiac amyloid patient and ATTR patient into the red range of the colour scale (the elevation is higher in AL, i.e. more red) compared to the normal control (green) and the patient with hypertrophic cardiomyopathy. Fontana et al. Circulation, 2015;132:

16 In Summary Cardiac Amyloidosis is a relatively common cause of HFpEF Echocardiography with decreased basal and preserved apical strain is highly suggestive of cardiac amyloidosis CMR can measure ECV and show typical DHE patterns of amyloidosis TC PYP imaging is currently the most sensitive and specific tool in ATTR cardiac amyloidosis Echocardiography, CMR and PYP are highly reliable tools in monitoring therapy Specialized Amyloidosis service is highly recommended in our institutions 16

17 Thank You for your attention 17