Prevalence, mutational spectrum and clinical implications of clonal hematopoiesis of indeterminate potential in plasma cell dyscrasias.

Clonal hematopoiesis of indeterminate potential (CHIP) is common both in healthy individuals and patients with hematological cancers. Recent studies have showed worse prognosis for patients with multiple myeloma (MM) and non-Hodgkin lymphoma undergoing stem cell transplant, that have concomitant presence of CHIP. Data regarding the clinical and biological role of CHIP in plasma cell dyscrasias (PCDs) is rapidly increasing. However, the prevalence and prognostic implication of CHIP in patients with MM outside of the transplant setting, and in those with other more indolent PCDs remains elusive. Here we explored the prevalence and clinical implications of CHIP detected through next-generation sequencing in 209 patients with PCDs including MM, light chain (AL) amyloidosis (ALA), monoclonal gammopathy of undetermined significance (MGUS), and smoldering multiple myeloma (SMM). To avoid attributing the mutations to the plasma cell clone, CHIP was defined as the presence of DNMT3A, TET2, or ASXL1 mutations in the peripheral blood or bone marrow (DTA-CH). The prevalence of DTA-CH was 19% in patients with PCDs, with no difference between each PCD. TET2 (23%) and DNMT3A (22%), were the most frequently mutated genes. DTA-CH correlated with older age in MM (P = .001) and MGUS/SMM (P = 0.0007), as well as with coronary artery disease or congestive heart failure in MM (P = .03). DTA-CH did not predict worse OS or PFS in either MM or ALA, nor it predict higher risk of progression to MM in patients with MGUS/SMM. Our results overall further elucidate the prevalence and mutational spectrum of CHIP in PCDs, providing more information regarding the clinical relevance of CHIP in this patient population.

High-Throughput Precision Phenotyping of Left Ventricular Hypertrophy With Cardiovascular Deep Learning.

IMPORTANCE: Early detection and characterization of increased left ventricular (LV) wall thickness can markedly impact patient care but is limited by under-recognition of hypertrophy, measurement error and variability, and difficulty differentiating causes of increased wall thickness, such as hypertrophy, cardiomyopathy, and cardiac amyloidosis. OBJECTIVE: To assess the accuracy of a deep learning workflow in quantifying ventricular hypertrophy and predicting the cause of increased LV wall thickness. DESIGN, SETTINGS, AND PARTICIPANTS: This cohort study included physician-curated cohorts from the Stanford Amyloid Center and Cedars-Sinai Medical Center (CSMC) Advanced Heart Disease Clinic for cardiac amyloidosis and the Stanford Center for Inherited Cardiovascular Disease and the CSMC Hypertrophic Cardiomyopathy Clinic for hypertrophic cardiomyopathy from January 1, 2008, to December 31, 2020. The deep learning algorithm was trained and tested on retrospectively obtained independent echocardiogram videos from Stanford Healthcare, CSMC, and the Unity Imaging Collaborative. MAIN OUTCOMES AND MEASURES: The main outcome was the accuracy of the deep learning algorithm in measuring left ventricular dimensions and identifying patients with increased LV wall thickness diagnosed with hypertrophic cardiomyopathy and cardiac amyloidosis. RESULTS: The study included 23 745 patients: 12 001 from Stanford Health Care (6509 [54.2%] female; mean [SD] age, 61.6 [17.4] years) and 1309 from CSMC (808 [61.7%] female; mean [SD] age, 62.8 [17.2] years) with parasternal long-axis videos and 8084 from Stanford Health Care (4201 [54.0%] female; mean [SD] age, 69.1 [16.8] years) and 2351 from CSMS (6509 [54.2%] female; mean [SD] age, 69.6 [14.7] years) with apical 4-chamber videos. The deep learning algorithm accurately measured intraventricular wall thickness (mean absolute error [MAE], 1.2 mm; 95% CI, 1.1-1.3 mm), LV diameter (MAE, 2.4 mm; 95% CI, 2.2-2.6 mm), and posterior wall thickness (MAE, 1.4 mm; 95% CI, 1.2-1.5 mm) and classified cardiac amyloidosis (area under the curve [AUC], 0.83) and hypertrophic cardiomyopathy (AUC, 0.98) separately from other causes of LV hypertrophy. In external data sets from independent domestic and international health care systems, the deep learning algorithm accurately quantified ventricular parameters (domestic: R2, 0.96; international: R2, 0.90). For the domestic data set, the MAE was 1.7 mm (95% CI, 1.6-1.8 mm) for intraventricular septum thickness, 3.8 mm (95% CI, 3.5-4.0 mm) for LV internal dimension, and 1.8 mm (95% CI, 1.7-2.0 mm) for LV posterior wall thickness. For the international data set, the MAE was 1.7 mm (95% CI, 1.5-2.0 mm) for intraventricular septum thickness, 2.9 mm (95% CI, 2.4-3.3 mm) for LV internal dimension, and 2.3 mm (95% CI, 1.9-2.7 mm) for LV posterior wall thickness. The deep learning algorithm accurately detected cardiac amyloidosis (AUC, 0.79) and hypertrophic cardiomyopathy (AUC, 0.89) in the domestic external validation site. CONCLUSIONS AND RELEVANCE: In this cohort study, the deep learning model accurately identified subtle changes in LV wall geometric measurements and the causes of hypertrophy. Unlike with human experts, the deep learning workflow is fully automated, allowing for reproducible, precise measurements, and may provide a foundation for precision diagnosis of cardiac hypertrophy.

Future Perspectives of Cardiovascular Biomarker Utilization in Cancer Survivors: A Scientific Statement From the American Heart Association.

Improving cancer survival represents the most significant effect of precision medicine and personalized molecular and immunologic therapeutics. Cardiovascular health becomes henceforth a key determinant for the direction of overall outcomes after cancer. Comprehensive tissue diagnostic studies undoubtedly have been and continue to be at the core of the fight against cancer. Will a systemic approach integrating circulating blood-derived biomarkers, multimodality imaging technologies, strategic panomics, and real-time streams of digitized physiological data overcome the elusive cardiovascular tissue diagnosis in cardio-oncology? How can such a systemic approach be personalized for application in day-to-day clinical work, with diverse patient populations, cancer diagnoses, and therapies? To address such questions, this scientific statement approaches a broad definition of the biomarker concept. It summarizes the current literature on the utilization of a multitude of established cardiovascular biomarkers at the intersection with cancer. It identifies limitations and gaps of knowledge in the application of biomarkers to stratify the cardiovascular risk before cancer treatment, monitor cardiovascular health during cancer therapy, and detect latent cardiovascular damage in cancer survivors. Last, it highlights areas in biomarker discovery, validation, and clinical application for concerted efforts from funding agencies, scientists, and clinicians at the cardio-oncology nexus.

Racial and Ethnic Disparities in Transthyretin Cardiac Amyloidosis.

Purpose of Review: Transthyretin amyloid cardiomyopathy (ATTR-CM) is a life-threatening disease that disproportionately affects older adults and people of African descent. This review discusses current knowledge regarding racial and ethnic disparities in the diagnosis and management of ATTR-CM. Recent Findings: Historically, ATTR-CM was thought to be a rare cause of heart failure. Recent evidence has shown that ATTR-CM is more common among older adults, men, and people of African descent. In addition, significant geographic variation exists in the identification of amyloid cardiomyopathy. Despite the high burden of ATTR-CM among Black individuals, most clinical data for ATTR-CM are from North America and Europe. Moreover, only a minority of clinical trial participants thus far have been Black patients. In addition to racial differences, socioeconomic disparities may be further compounded by the potentially prohibitive cost and limited accessibility of disease-modifying ATTR therapies. Summary: ATTR-CM is an important cause of heart failure that disproportionately affects people of African descent. Efforts to promote earlier identification of ATTR-CM in general practice will likely improve clinical outcomes for all groups. Future trials should strive to enroll a higher proportion of Black patients. Furthermore, enhanced efforts are warranted to improve treatment accessibility among racial and ethnic minority groups that may be more likely to be affected by ATTR-CM.

Outcomes in Patients With Cardiac Amyloidosis Undergoing Heart Transplantation.

OBJECTIVES: The purpose of this study is to report outcomes after heart transplantation in patients with cardiac amyloidosis based on a large single-center experience. BACKGROUND: Cardiac amyloidosis causes significant morbidity and mortality, often leading to restrictive cardiomyopathy, progressive heart failure, and death. Historically, heart transplantation outcomes have been worse in patients with cardiac amyloidosis compared with other heart failure populations, in part due to the systemic nature of the disease. However, several case series have suggested that transplantation outcomes may be better in the contemporary era, likely in part due to the availability of more effective light chain suppressive therapies for light chain amyloidosis. METHODS: This study examined all patients seen between 2004 and 2017, either at the Stanford University Medical Center or the Kaiser Permanente Santa Clara Medical Center, who were diagnosed with cardiac amyloidosis and ultimately underwent heart transplantation. This study examined pre-transplantation characteristics and post-transplantation outcomes in this group compared with the overall transplantation population at our center. RESULTS: During the study period, 31 patients (13 with light chain amyloidosis and 18 with transthyretin [ATTR] amyloidosis) underwent heart transplantation. Patients with ATTR amyloidosis were older, were more likely to be male, had worse baseline renal function, and had longer waitlist times compared with both patients with light chain amyloidosis and the overall transplantation population. Post-transplantation, there were no differences in post-operative bleeding, renal failure, infection, rejection, or malignancy. There was no significant difference in mortality between patients who underwent heart transplantation for amyloid cardiomyopathy and patients who underwent heart transplantation for all other indications. CONCLUSIONS: In carefully selected patients with cardiac amyloidosis, heart transplantation can be an effective therapeutic option with outcomes similar to those transplanted for other causes of heart failure.

Management of Cardiac Amyloidosis: Do's and Don'ts.

Cardiac amyloidosis is a potentially deadly disease characterized by progressive infiltration of amyloid fibrils, and it is increasingly recognized as an underdiagnosed but important cause of heart failure. Given its unique pathogenesis, there are key differences in the management of cardiac amyloidosis compared with other forms of heart failure. Moreover, the 2 common forms of cardiac amyloidosis, transthyretin and light-chain amyloidosis, are distinct entities with varying clinical manifestations and prognoses, leading to the need for tailored approaches to management. In the past decade, there have been many significant advances in the diagnosis and treatment of both forms of cardiac amyloidosis. For example, in selected cases, transthyretin cardiac amyloidosis can be diagnosed noninvasively with the use of bone scintigraphy imaging, avoiding the need for a biopsy. Effective, more targeted therapies have been developed for both transthyretin and light-chain amyloidosis. However, these treatments are much more effective in early stages of disease before significant end-organ amyloid deposition has occurred. Consequently, it is increasingly imperative that clinicians aggressively screen at-risk groups, identify early signs of disease, and initiate treatment. Finally, once thought to be ill advised, heart transplantation should be considered in carefully selected patients with end-stage cardiac amyloidosis, because transplant outcomes in these patients is now similar to other those for other cardiomyopathies. Given these and other recent changes in clinical practice, this article discusses several key considerations for the clinical care of patients with cardiac amyloidosis.

Harnessing Cardiac Regeneration as a Potential Therapeutic Strategy for AL Cardiac Amyloidosis.

PURPOSE OF REVIEW: Cardiac regeneration has received much attention as a possible means to treat various forms of cardiac injury. This review will explore the field of cardiac regeneration by highlighting the existing animal models, describing the involved molecular pathways, and discussing attempts to harness cardiac regeneration to treat cardiomyopathies. RECENT FINDINGS: Light chain cardiac amyloidosis is a degenerative disease characterized by progressive heart failure due to amyloid fibril deposition and light chain-mediated cardiotoxicity. Recent findings in a zebrafish model of light chain amyloidosis suggest that cardiac regenerative confers a protective effect against this disease. Cardiac regeneration remains an intriguing potential tool for treating cardiovascular disease. Degenerative diseases, such as light chain cardiac amyloidosis, may be particularly suited for therapeutic interventions that target cardiac regeneration. Further studies are needed to translate preclinical findings for cardiac regeneration into effective therapies.

Diagnosis and Treatment of Cardiac Amyloidosis Related to Plasma Cell Dyscrasias.

Light chain amyloidosis is a deadly disease in which a monoclonal plasma cell dyscrasia produces misfolded immunoglobulin light chains (AL) that aggregate and form rigid amyloid fibrils. The amyloid deposits infiltrate one or more organs, leading to injury and severe dysfunction. The degree of cardiac involvement is a major driver of morbidity and mortality. Early diagnosis and treatment are crucial to prevent irreversible end-organ damage and improve overall survival. Treatment of AL cardiac amyloidosis involves eliminating the underlying plasma cell dyscrasia with chemotherapy and pursuing supportive heart failure management.

Emerging Therapies for Transthyretin Cardiac Amyloidosis.

PURPOSE OF REVIEW: Transthyretin cardiac amyloidosis is an underdiagnosed, undertreated disease which is associated with significant morbidity and mortality. This review will discuss the recent advancements in novel therapies for transthyretin amyloidosis. RECENT FINDINGS: In recent phase 3 clinical trials, transthyretin stabilizers (tafamidis) and transthyretin silencers (patisiran and inotersen) have proven to be effective therapies for various forms of transthyretin amyloidosis. Understanding the recent and upcoming clinical trials for transthyretin amyloidosis will be important for improving the management of this challenging disease.

Geographic Disparities in Reported US Amyloidosis Mortality From 1979 to 2015: Potential Underdetection of Cardiac Amyloidosis.

Importance: Cardiac amyloidosis is an underdiagnosed disease and is highly fatal when untreated. Early diagnosis and treatment with the emerging novel therapies significantly improve survival. A comprehensive analysis of amyloidosis-related mortality is critical to appreciate the nature and distribution of underdiagnosis and improve disease detection. Objective: To evaluate the temporal and regional trends in age-adjusted amyloidosis-related mortality among men and women of various races/ethnicities in the United States. Design, Setting, and Participants: In this observational cohort study, death certificate information from the Centers for Disease Control and Prevention's Wide-ranging ONline Data for Epidemiologic Research database and the National Vital Statistics System from 1979 to 2015 was analyzed. A total of 30 764 individuals in the United States with amyloidosis listed as the underlying cause of death and 26 591 individuals with amyloidosis listed as a contributing cause of death were analyzed. Exposures: Region of residence. Main Outcomes and Measures: Age-adjusted mortality rate from amyloidosis per 1 000 000 population stratified by year, sex, race/ethnicity, and state and county of residence. Results: Of the 30 764 individuals with amyloidosis listed as the underlying cause of death, 17 421 (56.6%) were men and 27 312 (88.8%) were 55 years or older. From 1979 to 2015, the reported overall mean age-adjusted mortality rate from amyloidosis as the underlying cause of death doubled from 1.77 to 3.96 per 1 000 000 population (2.32 to 5.43 in men and 1.35 to 2.80 in women). Black men had the highest mortality rate (12.36 per 1 000 000), followed by black women (6.48 per 1 000 000). Amyloidosis contributed to age-adjusted mortality rates as high as 31.73 per 1 000 000 in certain counties. Most southern states reported the lowest US mortality rates despite having the highest proportions of black individuals. Conclusions and Relevance: The increased reported mortality over time and in proximity to amyloidosis centers more likely reflects an overall increase in disease diagnosis rather than increased lethality. The reported amyloidosis mortality is highly variable in different US regions. The lack of higher reported mortality rates in states with a greater proportion of black residents suggests underdiagnosis of amyloidosis, including cardiac forms of the disease, in many areas of the United States. Better understanding of the determinants of geographic and racial disparity in the reporting of amyloidosis deaths are warranted.

Novel pharmacotherapies for cardiac amyloidosis.

Amyloidosis refers to a range of protein misfolding disorders that can cause organ dysfunction through progressive fibril deposition. Cardiac involvement often leads to significant morbidity and mortality and increasingly has been recognized as an important cause of heart failure. The two main forms of cardiac amyloidosis, light chain (AL) and transthyretin (ATTR) amyloidosis, have distinct mechanisms of pathogenesis. Recent insights have led to the development of novel pharmacotherapies with the potential to significantly impact each disease. This review will summarize the preclinical and clinical data for these emerging treatments for AL and ATTR amyloidosis.