Left atrial reservoir strain by speckle tracking echocardiography : association with exercise capacity in chronic kidney disease

BACKGROUND: Left atrial (LA) function plays a pivotal role in modulating left ventricular performance. The aim of our study was to evaluate the relationship between resting LA function by strain analysis and exercise capacity in patients with chronic kidney disease (CKD) and evaluate its utility compared with exercise E/e’. METHODS AND RESULTS: Consecutive patients with stage 3 and 4 CKD without prior cardiac history were prospectively recruited from outpatient nephrology clinics and underwent clinical evaluation and resting and exercise stress echocardiography. Resting echocardiographic parameters including E/e’ and phasic LA strain (LA reservoir [LASr], conduit, and contractile strain) were measured and compared with exercise E/e’. A total of 218 (63.9±11.7 years, 64% men) patients with CKD were recruited. Independent clinical parameters associated with exercise capacity were age, estimated glomerular filtration rate, body mass index, and sex (P<0.01 for all), while independent resting echocardiographic parameters included E/e’, LASr, and LA contractile strain (P<0.01 for all). Among resting echocardiographic parameters, LASr demonstrated the strongest positive correlation to metabolic equivalents achieved (r=0.70; P<0.01). Receiver operating characteristic curves demonstrated that LASr (area under the curve, 0.83) had similar diagnostic performance as exercise E/e’ (area under the curve, 0.79; P=0.20 on DeLong test). A model combining LASr and clinical metrics showed robust association with metabolic equivalents achieved in patients with CKD. CONCLUSIONS: LASr, a marker of decreased LA compliance is an independent correlate of exercise capacity in patients with stage 3 and 4 CKD, with similar diagnostic value to exercise E/e’. Thus, LASr may serve as a resting biomarker of functional capacity in this population

Implicit bias in stroke care : a recurring old problem in the rising incidence of young stroke

Stroke is a leading cause of morbidity and mortality worldwide. Although the majority of strokes affect the elderly, the incidence of stroke in young patients is on the rise. Prompt recognition of stroke symptoms and time critical therapies play a key role in management and prognosis of this condition. This is especially critical in young stroke patients, for whom delays in early recognition and treatment can result in many years of disability with associated social and financial burden. Misdiagnosis and unwarranted variation in treatment of stroke in young patients is problematic. Clinician implicit bias, the unconscious and unintentional process of judgement in healthcare decision-making, is a contributor to the short-falls in outcomes in this population. Interventions in this process have been shown to improve clinical outcomes in young stroke patients and represent an active area of study

Cardiac vignette : isolated pulmonary regurgitation

Isolated pulmonary regurgitation (PR) is a rare occurrence with only a handful of documented cases worldwide. Though usually well tolerated in childhood, chronic PR can eventually lead to RV dysfunction and ventricular arrhythmias. In this cardiac vignette, we describe a case of isolated PR in a young female presenting with syncope and explore the natural history, different investigative modalities as well as issues in clinical management of this rare condition

Drivers of hospitalization in atrial fibrillation : a contemporary review

Atrial fibrillation (AF)–related hospitalization has risen over the last 2 decades and is the most influential determinant of total disease-related expenditure. In this review article, we describe several identified drivers of hospitalization from several registries and large-scale clinical trials, including key cardiovascular and non-traditional risk factors. We also discuss available assessment tools for discerning overall risk of hospitalization, including AF symptom scores, thrombosis and bleeding disposition, and non-invasive cardiac structural assessment. Finally, we highlight the different treatment paradigms that have been proven to reduce AF burden, progression, and hospitalization in the literature

Determinants of LA reservoir strain : independent effects of LA volume and LV global longitudinal strain

Background: Left atrial (LA) deformation during the reservoir phase (LASr) has demonstrated strong prognostic value in different clinical settings. Although determinants of left atrial reservoir strain including left atrial relaxation, left atrial compliance, and left ventricular longitudinal systolic function are fairly well defined, there is incomplete information regarding the effect of left atrial volume on this relationship which is the focus of our study. Method: Consecutive patients without prior cardiac disease referred for transthoracic echocardiography were prospectively recruited. All participants underwent clinical assessment, transthoracic echocardiography (TTE), and screening exercise stress test. Only patients with normal left ventricular ejection fraction (LVEF) without left ventricular hypertrophy (LVH) or myocardial ischemia on stress testing were included. Results: A total of 260 patients (57% male, mean age 59 ± 14 years) were included. 70% had hypertension, 33% had diabetes mellitus, and 31% had both HTN and DM. On multivariate analysis, age, e’, LAVI, and LV GLS (P < .01 for all) showed an independent association with LASr. Of interest, at lower tertiles of LAVI, a linear decrease in LASr was observed parallel to worsening LV GLS, whilst at higher tertiles of LAVI, the reduction in LASr was non-linear implying that LA enlargement, consequent to LA remodeling, had an incremental effect on LASr. Conclusion: Age, e’, LV GLS, and LAVI were independently associated with LASr. LA remodeling reflected by larger LAVI had an incremental negative association with LASr independent of LV GLS

Embolic stroke of undetermined source : approaches in risk stratification for cardioembolism

Ischemic stroke is a leading cause of morbidity and mortality worldwide. Embolic stroke of undetermined source has been recently proposed to categorize nonlacunar ischemic strokes without confirmed etiology after adequate investigation with a likely embolic stroke mechanism. A strategy of empirical anticoagulation for embolic stroke of undetermined source patients is attractive but may only be beneficial in a select subset of patients. Strategies which would help identify the subset of embolic stroke of undetermined source patients most likely to have cardioembolic origin of stroke, and hence benefit from anticoagulation, are needed. This article will review current evidence which may be useful in the development of a risk stratification approach based on arrhythmia monitoring, cardiac imaging, and clinical risk stratification. This approach may be beneficial in clinical practice in improving patient outcomes and reducing stroke recurrence in this population; however, further work is required with active trials underway

Integrated care in atrial fibrillation : a road map to the future

Atrial fibrillation (AF) is the most commonly encountered arrhythmia in clinical practice with an epidemiological coupling appreciated with advancing age, cardiometabolic risk factors, and structural heart disease. This has resulted in a significant public health burden over the years, evident through increasing rates of hospitalization and AF-related clinical encounters. The resultant gap in health care outcomes is largely twinned with suboptimal rates of anticoagulation prescription and adherence, deficits in symptom identification and management, and insufficient comorbid cardiovascular risk factor investigation and modification. In view of these shortfalls in care, the establishment of integrated chronic care models serves as a road map to best clinical practice. The expansion of integrated chronic care programs, which include multidisciplinary team care, nurse-led AF clinics, and use of telemedicine, are expected to improve AF-related outcomes in the coming years. This review will delve into current gaps in AF care and the role of integrated chronic care models in bridging fragmentations in its management

Usefulness of left atrial strain to predict end stage renal failure in patients with chronic kidney disease

Left atrial (LA) enlargement predicts adverse cardiovascular events in patients with chronic kidney disease (CKD). The aim of our study was to evaluate the value of LA reservoir strain, a novel measure of LA function, as a prognostic marker for adverse renal outcomes. A total of 280 patients (65.8 ± 12.2years, 63% male) with stable Stage 3 and 4 CKD without prior cardiac history were evaluated with transthoracic echocardiography and prospectively followed for up to 5 years. The primary end point was progressive renal failure, which was the composite of death from renal cause, end-stage renal failure and/or doubling of serum creatinine. Over a mean follow up of 3.9 ± 2.7years, 56 patients reached the composite endpoint. By log rank test, older age, lower baseline eGFR, anemia, diabetes mellitus, higher urinary albumin/creatinine ratio, number of antihypertensive medications, higher indexed left ventricular mass, larger LA volumes, and impaired LA reservoir strain were significant predictors of the composite outcome (p <0.01 for all). Multi-variable Cox regression analysis found LA reservoir strain, eGFR, number of antihypertensive medications and urinary albumin/creatinine ratio were independent predictors for progressive renal failure (p <0.01 for all). Impaired LA reservoir strain was associated with a 2.5-fold higher risk of the composite outcome (HR 2.51, 95% CI 1.19 to 5.30, p = 0.02) and was the only echocardiographic parameter that predicted progressive renal failure independent of established clinical risk factors for end-stage renal failure. Its utility requires validation in high risk CKD patients with cardiac disease

Clinical and cardiac structural predictors of atrial fibrillation persistence

Aims: The persistence of atrial fibrillation (AF) has been associated with differential clinical outcomes, with studies showing that persistent and permanent AF results in increased morbidity and mortality when compared to the paroxysmal subtype. Given the established prognostic implications of AF subtype, we sought to discern the clinical and structural cardiac parameters associated with persistent/ permanent AF. Materials and methods: Consecutive patients admitted to our institution between January 2013 and January 2018 with a primary diagnosis of non-valvular AF who underwent comprehensive transthoracic echocardiography were retrospectively appraised. Assessment of clinical and echocardiographic parameters was undertaken and compared according to AF subtype. Results: Of 1010 patients, 665 (mean age 66.8 ± 13.5 years, 53% men) had comprehensive transthoracic echocardiography on index admission and were included in the primary analysis. The majority of patients (n = 468; 70%) had paroxysmal AF while 197 (30%) had persistent/ permanent AF. Multivariable logistic regression analysis showed that heart failure (adjusted OR 3.135; 95% CI 2.099 to 4.682, P < .001), right atrial (RA) area ≥18 cm2(adjusted OR 2.147; 95% CI 1.413 to 3.261, P < .001) and left atrial emptying fraction (LAEF) ≤34% (adjusted OR 2.959; 95% CI 1.991 to 4.398, P < .001) were independent predictors of persistent /permanent AF. Conclusions: The presence of heart failure, increased RA size and impaired LA function were associated with persistent/ permanent AF. These clinical and cardiac structural risk markers of AF persistence may identify a target population for early intervention to prevent adverse cardiovascular outcomes

Association of left atrial metrics with atrial fibrillation rehospitalization and adverse cardiovascular outcomes in patients with nonvalvular atrial fibrillation following index hospitalization

Background: Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice, with significant clinical and economic burdens, largely driven by adverse cardiovascular outcomes and AF-related hospitalization. Left atrial (LA) parameters have been shown to have prognostic value in cardiovascular disease states. We sought to evaluate the prognostic value of measures of LA size and function, as measured through LA volume index and LA emptying fraction (LAEF), respectively, for AF rehospitalization and long-term adverse outcomes in patients with nonvalvular AF following index hospitalization. Methods: In this retrospective study, 594 consecutive patients (mean age, 67.8 ± 13.6 years, 53% men) admitted to a tertiary referral center with nonvalvular AF were assessed. Patients who underwent transthoracic echocardiography during their index admission and had complete follow-up data were included and followed for a mean period of 33.18 ± 21.27 months for the primary outcome of AF rehospitalization. The secondary outcome was a composite of all-cause death and major adverse cardiovascular events. Results: The primary outcome occurred in 250 (42%) patients, and the secondary outcome occurred in 219 (37%) patients. On multivariable regression analysis, LAEF had an independent association with AF rehospitalization (hazard ratio [HR] = 0.967; 95% CI, 0.953-0.982; P <.01), and time-dependent receiver operating characteristic curves demonstrated LAEF to have strong diagnostic accuracy in predicting early and intermediate AF rehospitalization. Both LA volume index (HR = 1.014; 95% CI, 1.003-1.026; P =.01) and LAEF (HR = 0.982; 95% CI, 0.970-0.993; P <.01) were associated with all-cause death and major adverse cardiovascular events. Conclusions: Adverse LA remodeling, as reflected through LA enlargement and reduced LA mechanical function, is associated with AF rehospitalization and long-term adverse cardiovascular outcomes in hospitalized patients with nonvalvular AF