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Transthyretin amyloid cardiomyopathy (ATTR‐CM) is caused by the cardiac deposition of insoluble amyloid fibrils formed by misfolded transthyretin proteins and is associated with various cardiac symptoms, such as progressive heart failure, conduction disturbance, and arrhythmia. The implementation of 99mtechnetium (99mTc)‐labelled bone radiotracer scintigraphy for diagnosing ATTR‐CM has enabled accurate diagnosis of the disease with high sensitivity and specificity and positioned this diagnostic modality as an integral part of disease diagnostic algorithms. In 2020, 99mTc‐pyrophosphate scintigraphy received exceptional approval for Japanese national health insurance reimbursement as a diagnostic method of ATTR‐CM. Nevertheless, the utility of 99mTc‐labelled bone radiotracer scintigraphy and the importance of an early diagnosis of suspected ATTR‐CM using this technique have yet to be internalized as common practice by general cardiologists, and guidance on daily clinical scenarios to consider this technique for a diagnosis of suspected ATTR‐CM is warranted. In this review, we discuss the utility of 99mTc‐labelled bone radiotracer scintigraphy for the early diagnosis of ATTR‐CM based on published literature and the outcomes of an advisory board meeting. This review also discusses clinical scenarios that could support early diagnosis of suspected ATTR‐CM as well as common pitfalls, correct implementation, and future perspectives of 99mTc‐labelled bone radiotracer scintigraphy in daily clinical practice. The clinical scenarios to consider 99mTc‐labelled bone radiotracer scintigraphy in daily practice may include, but are not limited to, patients with a family history of the hereditary type of disease; elderly patients (aged ≥60 years) with unexplained cardiac findings (e.g. cardiac hypertrophy associated with abnormalities on an electrocardiogram, heart failure with preserved ejection fraction associated with unexplained left ventricular hypertrophy, and heart failure with reduced ejection fraction associated with atrial fibrillation and left ventricular hypertrophy); and patients with cardiac hypertrophy associated with diastolic dysfunction, right ventricular/interatrial septum/valve thickness, left ventricular sparkling, or apical sparing. Cardiac hypertrophy and persistent elevation in cardiac troponin in elderly patients are also suggestive of ATTR‐CM. 99mTc‐labelled bone radiotracer scintigraphy is also recommended in patients with characteristic cardiac magnetic resonance findings (e.g. diffuse subendocardial late gadolinium enhancement patterns, native T1 increase, and increase in extracellular volume) or patients with cardiac hypertrophy and bilateral carpal tunnel syndrome.

Surgical treatment is an effective therapy and the gold standard for patients with left ventricular outflow tract obstruction (LVOTO) and drug‐refractory symptoms. However, it is difficult to arrange a concrete surgical plan due to the heterogenous and complex cardiac anatomy. Three‐dimensional (3D) printing is an emerging technology that is able to reproduce complex cardiac anatomy. Here, we present two patients with LVOTO in whom we created 3D printed models. In these two patients, we compared the 3D printed model and the intraoperative findings and confirmed that the 3D printed model we created could reproduce the complex cardiac anatomy including the interventricular septum, papillary muscles, and abnormally thickened chordae. By using 3D printed models, cardiologists and surgeons can comprehend the complex 3D cardiac structure and spatial positional relationship preoperatively and perform surgical rehearsal. 3D printing could be a valuable tool for the management of patients with LVOTO.

Tafamidis meglumine, a transthyretin (TTR) stabilizer, is effective in delaying the progression of neuropathy in TTR amyloidosis with Val30Met mutations. However, its efficacy in TTR amyloid cardiomyopathy is not fully elucidated. Herein, we report a 73-year-old Japanese man with a diagnosis of TTR amyloid cardiomyopathy with Val30Met mutation treated with tafamidis. To evaluate treatment response, cardiac magnetic resonance imaging was performed before and after 12 months of tafamidis treatment. Native T1, extracellular volume, and left ventricular mass showed no obvious worsening, and findings of other diagnostic studies also supported the efficacy of tafamidis to delay the progression of amyloid cardiomyopathy. Our case suggests that serial native T1 and extracellular volume may be novel non-invasive imaging methods to monitor the treatment response to TTR stabilizers in cardiac amyloidosis and also that tafamidis may be effective in suppressing cardiac progression in TTR amyloid cardiomyopathy with Val30Met mutation.

Although left ventricular (LV) systolic dysfunction in patients suffering from Takayasu arteritis (TA) has been reported, little is known regarding the development of heart failure in these patients. We report a novel finding of active TA and familial hypercholesterolaemia presenting with severe LV dysfunction through multimodality assessments of LV systolic dysfunction.

Both surgical myectomy and percutaneous transluminal septal myocardial ablation are effective treatments for drug-refractory symptomatic hypertrophic obstructive cardiomyopathy (HOCM). However, in some cases, it is not easy to elucidate the abnormal structure of left ventricular outflow obstruction to adopt these treatments. Here, we presented a young female patient with drug-refractory symptomatic HOCM. In this case, contrast-enhanced computed tomography enabled us to assess the suitability of percutaneous transluminal septal myocardial ablation. By creating three-dimensional printed models using computed tomography data, we could also visualize intracardiac structure and simulate the surgical procedure. A multimodality assessment strategy is useful for evaluating patients complicated with drug-refractory symptomatic HOCM.

The left ventricle is a less frequent location of cardiac myxomas overall. Meanwhile, cardiac myxomas related to Carney complex (CNC), which is a multiple neoplasia syndrome involving cardiac, endocrine, neural, and cutaneous tumours, more frequently occur in the left ventricle compared with sporadic cardiac myxomas. Herein, we report a case of a 20-year-old woman with CNC who underwent complete surgical excision of a large and mobile left ventricular myxoma. In our case, echocardiography performed 4 years earlier was normal. This case highlights the importance of annual follow-up by echocardiography in patients with CNC, because early diagnosis of cardiac myxomas might improve their prognosis. Besides, we should bear in mind the possibility of CNC if the patients have cardiac myxoma in a cardiac chamber other than the left atrium at a younger age.