An unusual case of cardiac amyloidosis

A Comprehensive Review on Chemistry and Biology of Tafamidis in Transthyretin Amyloidosis

Transthyretin amyloid cardiomyopathy and Transthyretin amyloid peripheral neuropathy are progressive disease conditions caused by Transthyretin amyloidosis (ATTR) fibril infiltration in the tissue. Transthyretin (TTR) protein misfolding and amyloid fibril deposits are pathological biomarkers of ATTR-related disorders. There are various treatment strategies targeting different stages in pathophysiology. One such strategy is TTR tetramer stabilization. Recently, a new TTR tetramer stabilizer, tafamidis, has been introduced that reduces the protein misfolding and amyloidosis and, consequently, disease progression in ATTR cardiomyopathy and peripheral neuropathy. This review will provide a comprehensive overview of the literature on tafamidis discovery, development, synthetic methods, pharmacokinetics, analytical methods and clinical trials. Overall, 7 synthetic methods, 5 analytical methods and 23 clinical trials have been summarized from the literature.

Detection and Diagnosis of Cardiac Amyloidosis in Egypt

Cardiac amyloidosis is a life-threatening disease that occurs when amyloid proteins, most commonly immunoglobulin light chain or transthyretin, mutate or become unstable, misfold, deposit as amyloid fibrils, and accumulate in the myocardium. Early diagnosis of cardiac amyloidosis is hindered by insufficient awareness, specifically regarding clinical red flags and diagnostic pathways. Cardiac amyloidosis diagnosis comprises two important phases, clinical suspicion (phase one) followed by definitive diagnosis (phase two). Each phase is associated with specific clinical techniques. For example, clinical features, electrocardiography, echocardiography, and cardiac magnetic resonance imaging serve to raise suspicion of cardiac amyloidosis and facilitate early diagnosis, whereas laboratory tests (i.e., blood or urine electrophoresis with immunofixation), biopsy, scintigraphy-based nuclear imaging, and genetic testing provide a definitive diagnosis of cardiac amyloidosis. In Egypt, both the lack of cardiac amyloidosis awareness amongst healthcare providers and the unavailability of clinical expertise for the use of diagnostic techniques must be overcome to improve the prognosis of cardiac amyloidosis in the region. Previously published diagnostic algorithms for cardiac amyloidosis have amalgamated techniques that can raise clinical suspicions of cardiac amyloidosis with those that definitively diagnose cardiac amyloidosis. Though such algorithms have been successful in developed countries, diagnostic tools like echocardiography, scintigraphy, and cardiac magnetic resonance imaging are not ubiquitously available across Egyptian facilities. This review presents the current state of knowledge regarding cardiac amyloidosis in Egypt and outlines a new diagnostic algorithm which leverages regional nuclear imaging expertise. Importantly, the proposed diagnostic algorithm guides accurate amyloid-typing to mitigate misdiagnosis and erroneous treatment selection and improve the cardiac amyloidosis diagnostic accuracy in Egypt.

The Value of Left Atrial Volume Changes in Predicting Cardiotoxicity in Patients Undergoing Anthracycline Chemotherapy

In order to study the value of left atrial volume three-dimensional echocardiography in predicting cardiotoxicity in patients with multiple myeloma undergoing anthracycline chemotherapy, a total of 53 patients with multiple myeloma who are treated in the Department of Hematology of our hospital from January 2018 to December 2020 are selected as the research object, and all patients underwent three cycles (T1-T3) of chemotherapy. Before and after each cycle of chemotherapy, the patients are examined with 3D ultrasound and serology detection. These patients are divided into the cardiotoxicity group and noncardiotoxicity group. The serological indexes and three-dimensional echocardiographic parameters between two groups are compared. Multivariate logistic regression is used to determine the independent risk factors of cardiotoxicity in patients undergoing chemotherapy. And ROC curves are performed to evaluate the diagnostic value of related indicators in predicting cardiotoxicity. A total of 53 patients with multiple myeloma are included in this study. Serological indexes (T3 cTnI and T3 Pro-BNP), T2 LAVmin, T3 LAVmin, T2 LAVprep, and T3 LAVprep in the cardiotoxicity group are significantly higher than those in the noncardiotoxicity group. Multivariate logistic regression further found that T3 cTnI, T3 Pro-BNP, T2 LAVmin, T3 LAVmin, T2 LAVprep, T3 LAVprep could be used to predict the occurrence of cardiotoxicity (P < 0.05). The results of ROC curves showed that T3 LAVmin had the most diagnostic efficiency of cardiotoxicity (AUC = 0.938; sensitivity 75.72%; specificity 93.82%). Detection of changes in left atrial volume using three-dimensional ultrasound could be used as strong predictors of cardiotoxicity caused by anthracycline chemotherapy drugs in patients with multiple myeloma.

Myocardial Injury in Multiple Myeloma Patients With Preserved Left Ventricular Ejection Fraction: Noninvasive Left Ventricular Pressure-Strain Myocardial Work

Introduction

Over one-half of patients with multiple myeloma (MM) die of heart failure or arrhythmia. Left ventricular ejection fraction (LVEF) is used to describe left ventricular systolic function. However, depressed LVEF means advanced stage of left ventricular dysfunction in patients with MM. Left ventricular pressure-strain-derived myocardial work (LVMW) is a novel and noninvasive method for evaluating LV function related to LV dynamic pressure load. MW is assessed by LV MW index (LVMWI), constructive work, wasted work, and LV MW efficiency (LVMWE). In this study, we aimed to investigate the value of LVMW in cardiac function assessment and clinical prognosis of MM patients with preserved LVEF.

Methods

A total of 72 subjects, including 40 untreated MM patients with preserved EF (including the thick wall and normal wall groups) and 32 non-MM patients, were enrolled in this study. Laboratory data and clinical history of all the patients were collected. All the patients underwent comprehensive echocardiographic examinations and then LVMWI and LVMWE were calculated. Moreover, cardiac adverse events (CAEs) were observed in MM patients treated with bortezomib-based therapy after 6 months and the prognostic value of MW was assessed.

Results

(1) LV myocardial global work index (GWI), myocardial global work efficiency (GWE), and global longitudinal strain (GLS) were lower in the thick wall group of patients with MM compared with the normal wall group and controls. Cardiac segmental analysis of LVMWI in patients with MM showed an apical sparing pattern; (2) The area under the curve (AUC) of GWE for judging the disease severity based on the Revised International Staging System (R-ISS) was 0.835 (95% CI: 0.684–0.933, p < 0.05); (3) GWE, Lg_dFLC, and arrhythmia were independent risk factors of CAEs. The AUC of GWE for predicting CAEs in MM patients treated with bortezomib-based therapy for 6 months follow-up was 0.896 (95% CI: 0.758–0.970, p < 0.05).

Conclusion

MM Patients with preserved EF had subclinical LV systolic dysfunction, which was worse in the thick wall group. LVMWI was presented as “apical sparing” in patients with MM. A lower LVGWE may have a predictive value for CAEs in patients with MM after 6 months of follow-up.