Temporal Trends in Diagnostic Testing Patterns for Wild-Type Transthyretin Amyloid Cardiomyopathy in the Medicare Fee-for-Service Population.

Wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM) is frequently misdiagnosed or diagnosed late in the disease course. ATTRwt-CM can be diagnosed invasively through tissue biopsy, but current diagnostic recommendations indicate technetium-99m pyrophosphate (99mTc-PYP) bone scintigraphy is an acceptable noninvasive alternative. The relative use of these confirmatory diagnostic tests in routine clinical practice is unknown. A retrospective observational study assessed temporal trends in biopsy and 99mTc-PYP scintigraphy and differences in patient characteristics using in/outpatient claims data from the US Medicare fee-for-service database. Claims prevalence for biopsy alone (≥1 claim for cardiac/extracardiac biopsy), imaging alone (≥1 claim for 99mTc-PYP scintigraphy), and both tests and patient demographic, geographic, and clinical characteristics were examined. Of patients (n = 1226) receiving an ATTRwt-CM diagnostic code, 29%, 47%, and 24% were diagnosed by biopsy alone, 99mTc-PYP scintigraphy alone, and both tests, respectively. Patients with claims for 99mTc-PYP scintigraphy alone were older than those with claims for biopsy alone (79.9 vs 76.5; p <0.001). Fewer patients in the southern United States and more patients in the northeastern United States had claims for 99mTc-PYP scintigraphy alone than biopsy alone (p <0.001). There was a temporal trend toward more claims for 99mTc-PYP scintigraphy alone (odds ratio 1.21; p <0.001) and both tests (odds ratio 1.10; p = 0.008) versus biopsy alone. From 2017 to 2019, claims increased for 99mTc-PYP scintigraphy alone. In conclusion, these data suggest a growing preference for the noninvasive imaging technique, which has high sensitivity/specificity, usability, and accessibility and may help facilitate earlier disease diagnosis. United States regional differences in the use of 99mTc-PYP scintigraphy highlight the need for education initiatives.

Functional and Economic Impact of INOCA and Influence of Coronary Microvascular Dysfunction.

OBJECTIVES: This study sought to better characterize the quality of life and economic impact in patients with symptoms of ischemia and no obstructive coronary disease (INOCA) and to identify the influence of coronary microvascular dysfunction (CMD). BACKGROUND: Patients with INOCA have a high symptom burden and an increased incidence of major adverse cardiac events. CMD is a frequent cause of INOCA. The morbidity associated with INOCA and CMD has not been well-characterized. METHODS: Sixty-six patients with INOCA underwent stress cardiac magnetic resonance with calculation of myocardial perfusion reserve (MPR); MPR 2.0 to 2.4 was considered borderline-reduced (possible CMD) and MPR <2.0 was defined as reduced (definite CMD). Subjects completed quality of life questionnaires to assess the morbidity and economic impact of INOCA. Questionnaire results were compared between INOCA patients with and without CMD. In addition, logistic regression was used to determine the predictors of CMD within the INOCA population. RESULTS: The prevalence of definite CMD was 24%. Definite or borderline CMD was present in 59% (MPR ≤2.4). Patients with INOCA reported greater physical limitation, angina frequency, and reduced quality of life compared to referent stable coronary artery disease and acute myocardial infarction populations. In addition, Patients with INOCA reported frequent time missed from work and work limitations, suggesting a substantial economic impact. No difference was observed in reported symptoms between INOCA patients with and without CMD. Glomerular filtration rate and body-mass index were significant predictors of CMD in multivariable regression analysis. CONCLUSIONS: INOCA is associated with high morbidity similar to other high-risk cardiac populations, and work limitations reported by Patients with INOCA suggest a substantial economic impact. CMD is a common cause of INOCA but is not associated with increased morbidity. These results suggest that there is significant symptom burden in the INOCA population regardless of etiology.