Assessment and Management of Atrial Fibrillation in Older Adults with Frailty.

Atrial fibrillation (AF) is a major driver of morbidity and mortality among older adults with frailty. Moreover, frailty is highly prevalent in older adults with AF. Understanding and addressing the needs of frail older adults with AF is imperative to guide clinicians caring for older adults. In this review, we summarize current evidence to support the assessment and management of older adults with AF and frailty, incorporating numerous recent landmark trials and studies in the context of the 2023 US AF guideline.

Frailty and Cardiovascular Health.

The incidence of frailty and cardiovascular disease (CVD) increases as the population ages. There is a bidirectional relationship between frailty and CVD, and both conditions share several risk factors and underlying biological mechanisms. Frailty has been established as an independent prognostic marker in patients with CVD. Moreover, its presence significantly influences both primary and secondary prevention strategies for adults with CVD while also posing a barrier to the inclusion of these patients in pivotal clinical trials and advanced cardiac interventions. This review discusses the current knowledge base on the relationship between frailty and CVD, how managing CVD risk factors can modify frailty, the influence of frailty on CVD management, and future directions for frailty detection and modification in patients with CVD.

Initiation of oral anticoagulation in US older adults newly diagnosed with atrial fibrillation during hospitalization.

BACKGROUND: Atrial fibrillation is a common cause of stroke among older adults and is often first detected during hospitalization, given frequent use of cardiac telemetry. METHODS: In a 20% national sample of Medicare fee-for-service beneficiaries, we identified patients aged 65-or-older newly diagnosed with atrial fibrillation while hospitalized in 2016. Our primary outcome was an oral anticoagulant claim within 7-days of discharge. Multivariable logistic regression analyses assessed relationships between anticoagulation initiation and thromboembolic and bleeding risk scores while controlling for demographics, frailty, comorbidities, and hospitalization characteristics. RESULTS: Among 38,379 older adults newly diagnosed with atrial fibrillation while hospitalized (mean age 78.2 [SD 8.4]; 51.8% female; 83.3% white), 36,633 (95.4%) had an indication for anticoagulation and 24.6% (9011) of those initiated an oral anticoagulant following discharge. Higher CHA2 DS2 -VASc score was associated with a small increase in oral anticoagulant initiation (predicted probability 20.5% [95% CI, 18.7%-22.3%] for scores <2 and 24.9% [CI, 24.4%-25.4%] for ≥4). Elevated HAS-BLED score was associated with a small decrease in probability of anticoagulant initiation (25.4% [CI, 24.4%-26.4%] for score <2 and 23.1% [CI, 22.5%-23.8%] for ≥3). Frailty was associated with decreased likelihood of oral anticoagulant initiation (24.7% [CI, 23.2%-26.2%] for non-frail and 18.1% [CI, 16.6%-19.6%] for moderately-severely frail). Anticoagulant initiation varied by primary reason for hospitalization, with predicted probability highest among patients with a primary diagnosis of atrial fibrillation (46.1% [CI, 45.0%-47.3%]) and lowest among those with non-cardiovascular conditions (13.8% [CI, 13.3%-14.3%]) and bleeds (3.6% [CI, 2.4%-4.8%]). CONCLUSIONS: Oral anticoagulant initiation is uncommon among older adults newly diagnosed with atrial fibrillation during hospitalization, even among patients hospitalized primarily for atrial fibrillation and patients with high thromboembolic risk. Clinicians should discuss risks and benefits of oral anticoagulants with all inpatients found to have atrial fibrillation.

Histopathology of the Mitral Valve Residual Leaflet in Obstructive Hypertrophic Cardiomyopathy.

BACKGROUND: Mitral valve (MV) elongation is a primary hypertrophic cardiomyopathy (HCM) phenotype and contributes to obstruction. The residual MV leaflet that protrudes past the coaptation point is especially susceptible to flow-drag and systolic anterior motion. Histopathological features of MVs in obstructive hypertrophic cardiomyopathy (OHCM), and of residual leaflets specifically, are unknown. OBJECTIVES: The purpose of this study was to characterize gross, structural, and cellular histopathologic features of MV residual leaflets in OHCM. On a cellular-level, we assessed for developmental dysregulation of epicardium-derived cell (EPDC) differentiation, adaptive endocardial-to-mesenchymal transition and valvular interstitial cell proliferation, and genetically-driven persistence of cardiomyocytes in the valve. METHODS: Structural and immunohistochemical staining were performed on 22 residual leaflets excised as ancillary procedures during myectomy, and compared with 11 control leaflets from deceased patients with normal hearts. Structural components were assessed with hematoxylin and eosin, trichrome, and elastic stains. We stained for EPDCs, EPDC paracrine signaling, valvular interstitial cells, endocardial-to-mesenchymal transition, and cardiomyocytes. RESULTS: The residual leaflet was always at A2 segment and attached by slack, elongated and curlicued, myxoid chords. MV residual leaflets in OHCM were structurally disorganized, with expanded spongiosa and increased, fragmented elastic fibers compared with control leading edges. The internal collagenous fibrosa was attenuated and there was collagenous tissue overlying valve surfaces in HCM, with an overall trend toward decreased leaflet thickness (1.09 vs 1.47 mm, P = 0.08). No markers of primary cellular processes were identified. CONCLUSIONS: MV residual leaflets in HCM were characterized by histologic findings that were likely secondary to chronic hemodynamic stress and may further increase susceptibility to systolic anterior motion.