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

Tissue doppler imaging in echocardiography : value and limitations

Tissue Doppler imaging (TDI) is a useful echocardiographic technique to evaluate global and regional myocardial systolic as well as diastolic function. It can also be used to quantify right ventricular and left atrial function. Recent studies have demonstrated its utility as a diagnostic as well as prognostic tool in different cardiac conditions including coronary artery disease, heart failure (both systolic and diastolic), valvular heart disease, cardiomyopathies as well as constrictive pericarditis. TDI measurements are also helpful to identify patients who will benefit from cardiac resynchronisation therapy. Even though it is reproducible and relatively easy to obtain, it is underutilised in routine clinical practice. TDI is readily available on most commercially available echocardiographic systems, and we recommend that TDI be used for routine clinical echocardiographic evaluation of patients

Cardiac biomarkers in Chronic Kidney Disease

The majority of patients with end stage renal disease die of cardiovascular causes. Comorbid conditions like diabetes and hypertension are shared by both chronic kidney disease (CKD) and cardiovascular disease. To help physicians to identify high risk CKD patients, there is a need of sensitive biomarker to detect subclinical cardiac abnormalities in the early stages of CKD to permit initiation of necessary therapeutic intervention.CKD results in several alterations in cardiovascular structure and function. We hypothesized that left atrial (LA) volume and LA strain would be sensitive markers of myocardial involvement in early CKD even in the presence of co existent diabetes and hypertension. We also hypothesized that LA metrics would be more sensitive parameters than LV parameters. We further hypothesized that LA metrics may be more sensitive than the measurement of N terminal brain naturetic peptide (NT- ProBNP) to detect myocardial dysfunction in CKD patients.To prove these congruent hypotheses, we recruited three groups of patients; the first group comprised of stage 3 CKD patients (30-59mL/min/1.73m2) with or without hypertension and or diabetes but without any previous cardiac events. Control groups were age and sex matched subjects with hypertension and or diabetes with normal renal function, without any previous cardiac history and the third group comprised of healthy adults. We additionally studied patients with diabetes and hypertension without CKD, to examine the independent effect of these conditions on LA parameters.We found that LA metrics were significantly reduced in both the CKD group and the risk factor matched control group, compared with normal subjects. Importantly, LA metrics were significantly altered in CKD patients compared to risk factor matched subjects indicating these parameters are sensitive markers to detect myocardial involvement despite the presence of coexistent hypertension and diabetes. LA volume and strain also showed incremental value in diagnosing myocardial dysfunction in CKD in the presence of hypertension and diabetes. Finally we compared LA parameters withNT- ProBNP; even though NT- ProBNP was significantly elevated in CKD patients compared to the control group, levels were below the upper normal reference range whereas LA metrics were significantly altered compared to control group. These findings indicate that LA metrics are a sensitive, non-invasive tool to detect myocardial involvement in early CKD

Lung cancer mimicking left atrial mass

Cardiac involvement in lung cancer is found in up to 25% of autopsy cases. However, despite the considerable mortality and morbidity associated with cardiac metastasis, antemortem diagnosis is unusual. A rare case of lung cancer presenting as a left atrial mass is reported

Exercise E/e' is a determinant of exercise capacity and adverse cardiovascular outcomes in chronic kidney disease

Objectives: This study sought to assess the relationship between E/e′ and exercise capacity in patients with chronic kidney disease (CKD) and evaluate its prognostic role. Background: Patients with CKD have diastolic dysfunction, reduced physical fitness, and elevated risk of cardiovascular disease. Methods: Patients with stage 3 and 4 CKD without previous cardiac disease underwent resting and exercise stress echocardiograms with assessment of exercise E/e′. Patients were compared to age-, sex-, and risk factor–matched control individuals and were followed annually for 5 years for cardiovascular death and major adverse cardiovascular event(s) (MACE). Exercise capacity was assessed as metabolic equivalents (METs), with reduced exercise capacity defined as METs of ≤7. Raised exercise E/e′ was defined as >13. Results: A total of 156 patients with CKD (age 62.8 ± 10.6 years; male: 62%) were compared to 156 matched control individuals. Patients with CKD were more likely to be anemic (p 13 was an independent predictor of cardiovascular death and MACE on unadjusted and adjusted hazard models. Conclusion: E/e′ is a strong predictor of exercise capacity and METs achieved by patients with CKD. Exercise capacity was reduced in patients with CKD, presumably consequent to diastolic dysfunction. Elevated exercise E/e′ in patients with CKD is an independent predictor of cardiovascular death and MACE

Changes in left atrial volume in diabetes mellitus : more than diastolic dysfunction?

To evaluate left atrial (LA) volume and function as assessed by strain and strain rate derived from 2D speckle tracking and their association with diastolic dysfunction (DD) in patients with diabetes mellitus (DM). Seventy three patients with DM were compared with age- and gender-matched normal controls; 30 patients with DM alone were compared to those with hypertension (HT) alone. The maximum LA volume, traditional measures of atrial function, 2D strain and strain rate were analysed. The LA indexed volume (LAVI) was larger in DM group than that in normal controls (38.2 9.9 vs. 20.5 4.8 ml/m(2), P 0.0001), as well as in DM alone compared with hypertensive patients (33.9 10 vs. 25.7 8 ml/m(2), P 0.0001). Global strain was significantly reduced in the DM group compared with that in normal controls (22.5 8.67 vs. 30.6 8.27; P 0.0001) but was similar with HT. There was a weak correlation between LAVI and global strain with increasing grades of DD (r 0.439, P 0.0001 and r 0.316, P 0.0001, respectively) in the diabetic group. However, there was no significant difference in LAVI between these groups. A logistic regression analysis for predictors of LAVI demonstrated that only diabetes was a determinant of LAVI. Patients with diabetes showed a significant reduction in global strain compared with normal controls but no difference with increasing grades of diastolic function. LA enlargement in DM is independent of associated HT and diastolic function. LA enlargement is associated with LA dysfunction as evaluated by 2D strain. It is likely that a combination of DD and a diabetic atrial myopathy contribute to LA enlargement in patients with DM

Exploration of cardiology patient hospital presentations, health care utilisation and cardiovascular risk factors during the COVID-19 pandemic

Objectives: COVID-19 and the lockdowns have affected health care provision internationally, including medical procedures and methods of consultation. We aimed to assess the impact of COVID-19 at two Australian hospitals, focussing on cardiovascular hospital admissions, the use of community resources and cardiovascular risk factor control through a mixed methods approach. Methods: Admissions data from the quaternary referral hospital were analysed, and 299 patients were interviewed from July 2020 to December 2021. With the admissions data, the number, complexity and mortality of cardiology hospital admissions, prior to the first COVID-19 lockdown (T0=February 2018–July 2019) were compared to after the introduction of COVID-19 lockdowns (T1=February 2020–July 2021). During interviews, we asked patients about hospital and community health resource use, and their control of cardiovascular risk factors from the first lockdown. Results: Admission data showed a reduction in hospital presentations (T0=138,099 vs T1=128,030) and cardiology admissions after the lockdown period began (T0=4,951 vs T1=4,390). After the COVID-19-related lockdowns began, there was an increased complexity of cardiology admissions (T0=18.7%, 95% CI 17.7%–19.9% vs T1=20.3%, 95% CI 19.1%–21.5%, chi-square test: 4,158.658, p<0.001) and in-hospital mortality (T0=2.3% of total cardiology admissions 95% CI 1.9%–2.8% vs T1=2.8%, 95% CI 2.3%–3.3%, chi-square test: 4,060.217, p<0.001). In addition, 27% of patients delayed presentation due to fears of COVID-19 while several patients reported reducing their general practitioner or pathology/imaging appointments (27% and 11% respectively). Overall, 19% reported more difficulty accessing medical care during the lockdown periods. Patients described changes in their cardiovascular risk factors, including 25% reporting reductions in physical activity. Conclusion: We found a decrease in hospital presentations but with increased complexity after the introduction of COVID-19 lockdowns. Patients reported being fearful about presenting to hospital and experiencing difficulty in accessing community health services

Independent echocardiographic markers of cardiovascular involvement in chronic kidney disease : the value of left atrial function and volume

Background: Chronic kidney disease (CKD) is associated with increased cardiovascular mortality and morbidity, particularly ischemic heart disease and cardiomyopathy. Newer echocardiographic techniques such as myocardial strain analysis provides the opportunity to detect early myocardial dysfunction. The aim of this study was to examine echocardiographic parameters, in particular left atrial (LA) function and volume, in patients with CKD. A further aim was to determine echocardiographic parameters that are sensitive to detect cardiovascular involvement in early CKD. Methods: Seventy-six patients with stage 3 CKD (estimated glomerular filtration rate, 30–59 mL/min/1.73 m2) with hypertension and/or diabetes mellitus, without any previous cardiac illness, were prospectively recruited. These patients were compared with subjects matched for age, sex, and risk factors (hypertension and/or diabetes mellitus) with normal renal function and 76 healthy age-matched control subjects. Two-dimensional strain analyses of the left atrium and left ventricle were performed. Comprehensive echocardiographic examinations were performed in all participants, and traditional echocardiographic parameters including indexed LA volume (LAVI) and two-dimensional strain analysis of the left ventricle and left atrium were performed in all participants. Differences among the three groups on demographic, clinical, and echocardiographic parameters were examined. Results: LA systolic strain (20.9 6 6.3%vs 27.4 6 7.9%, P < .0001) and systolic and late diastolic strain rates were altered in the CKD group, while early diastolic strain rate was similar to that in the risk factor–matched group. LAVI was significantly larger in the CKD group compared with the risk factor–matched group and healthy control subjects (38.5 610 vs 31.2 69 vs 22.3 65mL/m2, P < .0001). LV strain as well as LV systolic and early diastolic strain rates were similar in the CKD and risk factor–matched groups. LV late diastolic strain rate, a surrogate measure of LA contractile function, was, however, reduced in the CKD group. Forward logistic regression analysis showed LA global strain to be the most sensitive predictor for the presence of CKD, followed by LAVI; though LV late diastolic strain rate was reduced in the CKD group, it was not an independent predictor. Furthermore, the addition of LA strain to traditional echocardiographic parameters significantly increased the predictive power to detect cardiovascular involvement (C statistic = 0.65 vs C statistic = 0.84, P < .0001). Increased LAVI, reduced left ventricular global strain, and the presence of CKD were independent predictors of LA strain, while left ventricular mass index, E/e0 ratio, and the presence of CKD were predictors of LAVI. Conclusion: LA strain and LAVI are more sensitive parameters than traditional echocardiographic parameters as well as left ventricular strain in patients with early CKD. LA strain and LAVI may be useful to detect myocardial involvement in stage 3 CKD, and LA alterations may be consequent to increased activation of the renin-angiotensin-aldosterone pathway, causing myocardial fibrosis in CKD