Key Information
Clinical pathways in the evaluation and management of cardiac amyloidosis (CA) are haphazard in Malaysia. Presented here are two cases that serve as examples of how diagnosis of CA can often be missed or delayed, leading to serious consequences. A complex interplay between various factors contributes to this, including lack of expertise and facilities to support early recognition and confirmation of CA affecting laboratory services, radiological services, and expertise in the disease. A lack of coordinated care involving various disciplines and subspecialties has been a barrier in establishing a national-level clinical pathway for CA. Additionally, there is poor awareness among clinicians surrounding CA, where limited experience in managing the disease is concentrated in major centres. Building an amyloidosis network may be the way forward, as the onus is on clinicians to improve the way they communicate with each other.
Keywords
Cardiac amyloidosis, transthyretin cardiac amyloidosis, light chain cardiac amyloidosis, Malaysia, global perspectives
Disclosure:The authors have no conflicts of interest to declare. Received:12 August 2023 Accepted:29 January 2024
Published online:02 April 2024 Citation:Journal of Asian Pacific Society of Cardiology 2024;3:e05
DOI:https://doi.org/10.15420/japsc.2023.32
Informed Consent: All patients have given written informed consent.
Correspondence Details:Raja Ezman Raja Shariff, Department of Cardiology, Universiti Teknologi MARA Sungai Buloh, Jalan Hospital, 47000, Selangor, Malaysia. E: rajaezman@gmail.com
Open Access: This work is open access under the CC-BY-NC 4.0 License which allows users to copy, redistribute and make derivative works for non-commercial purposes, provided the original work is cited correctly.
In the past decade, there has been increasing interest surrounding cardiac amyloidosis (CA), partly due to the availability of effective therapies for transthyretin CA (ATTR-CA).1,2 Unfortunately, such progress has been largely limited to developed countries, with little to no progress seen in countries like Malaysia. In fact, clinical pathways in the initial evaluation and management of CA remain sparse in Malaysia, although an Asian consensus document does exist.3 There is a complex interplay between various factors (Figure 1), and using two case examples, we highlight these barriers.
Case 1
An 81-year-old man presented to a district hospital following an 18-month history of worsening dyspnoea, reduced effort tolerance and peripheral oedema. Clinical examination revealed a blood pressure of 95/68 mmHg with oxygen saturation of 88% on room air. The patient appeared cachectic, with dullness to percussion and reduced breath sounds in the right lower zone of his lungs. Initial N-terminal pro B-type natriuretic peptide (NT-proBNP) was 24,000 ng/l and high-sensitivity troponin T was 78 mmol/l. Transthoracic echocardiography (TTE) demonstrated preserved a left ventricular ejection fraction (LVEF) of 60%, severe left ventricular hypertrophy (Figure 2) with markedly reduced medial e’ (0.02 m/s) and lateral e’ (0.03 m/s). The patient was referred to and later reviewed at our clinic 6 months after his initial presentation. A clinical suspicion of CA was raised, leading to a cardiac MRI. Patchy, transmural late gadolinium enhancement (LGE) was seen, but unfortunately, extracellular volume (ECV) quantification was not performed as it was unavailable. Instead, non-conventional dark blood pool sequence was performed revealing diffuse, heterogenous transmural LGE, suggestive of infiltrative disease. Alongside the MRI, monoclonal light chain assessment was performed with unremarkable results, but it accrued a 2-month delay due to being outsourced for immunofixation. The patient was then referred for a technetium-99m pyrophosphate (Tn-99m PYP) scan which had to be performed externally to the National Cancer Institute due to limited expertise at the centre and neighbouring hospital (Figure 2). The test, which took approximately 3 months to obtain, demonstrated a heart:contralateral (H:CL) ratio of 1.69 and Perugini grade 3, which were highly diagnostic of ATTR-CA.