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

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

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

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

Early effects of ticagrelor versus clopidogrel on peripheral endothelial function after non-ST-elevation acute coronary syndrome and assessment of its relationship with coronary microvascular function

Peripheral endothelial dysfunction is an independent predictor of adverse long-term prognosis after acute coronary syndrome. Data are lacking on the effects of oral P2Y12-inhibitors on peripheral endothelial function in non–ST-elevation acute coronary syndrome (NSTEACS). Furthermore, the relation between peripheral endothelial function and invasive indexes of coronary microvascular function in NSTEACS is unclear. Between March 2018 and July 2020, hospitalized patients with NSTEACS were randomized (1:1) to ticagrelor or clopidogrel. Peripheral endothelial function was assessed with brachial artery flow-mediated vasodilation (FMD). Invasive indexes of coronary microvascular function were obtained using an intracoronary pressure-temperature sensor-tipped wire. In 70 patients included, mean age was 58.6 years, 78.6% (n = 55) were male and 20% (n = 14) had diabetes mellitus. Compared with clopidogrel, ticagrelor significantly improved FMD (14.2 ± 5.4% vs 8.9 ± 5.3%, p 34 as the threshold, with 77.6% sensitivity and 52.4% specificity. In patients who did not have a percutaneous coronary intervention, an FMD of 11.49% identified an IMR of >34 with 84.6% sensitivity and 80% specificity. In conclusion, ticagrelor significantly improved peripheral endothelial function compared with clopidogrel in patients with NSTEACS. There was a significant correlation between brachial artery FMD and IMR of the infarct-related artery

Chronic kidney disease is independently associated with alterations in left atrial function

Background: Chronic kidney disease (CKD) is associated with increased cardiovascular morbidity and mortality; hence detection of early cardiovascular involvement in CKD is important to prevent future adverse cardiovascular events. Left atrial (LA) enlargement and dysfunction has been reported in end stage renal disease. However, there is a paucity of published data regarding the evaluation of LA function in CKD using noninvasive imaging parameters. In this study, we evaluated biplane LA volume as well as LA function (LA global systolic strain (GS) and strain rate [SR]) in stage 3 CKD patients (eGFR 30-59 mL/min per 1.73 m2) to determine if LA function parameters are more significantly altered by the presence of CKD in addition to changes due to hypertension alone. Methods: Thirty-three CKD patients (eGFR 30-59 mL/min per 1.73 m2) with hypertension were compared to 33 normal controls and 34 hypertensive (HT) subjects with normal renal function; all participants underwent a detailed transthoracic echocardiogram. Indexed biplane LA volume (LAVI), LA segmental function, and GS and SR (systolic, early, and late diastole) derived from tissue Doppler imaging (TDI) were measured. Univariate predictors of LA strain were determined. Multiple logistic regression analysis was used to examine the effect of patient group (i.e. CKD) on GS and SR as well as LAVI. Results: Left atrial volume indexed was significantly increased in both the HT and CKD with HT group compared to normal controls (28 ± 9 mL/m2 vs. 28 ± 9 mL/m2 vs. 23 ± 5 mL/m2, respectively, P = 0.02). However, LAVI was similar in the HT and CKD with HT group (28 ± 9 mL/m2 vs. 28 ± 9 mL/m2; P = NS). LA GS and SR were reduced in both the CKD with HT and HT group, compared to controls. However, a significantly lower LA GS was present in the CKD with HT group (Controls vs. HT vs. CKD with HT: 54.9 ± 14.5% vs. 34.5 ± 6.2% vs. 25.7 ± 9.3%, respectively; P = 0.001). To examine the effect of group, (i.e. presence of CKD) multiple logistic regression analysis was performed with univariate predictors including indexed left ventricular mass (LVMI), LV diastolic grade, LAVI, peak A-wave velocity, β-blocker therapy, GS and SR; this demonstrated that CKD had an independent effect on LA GS and SR (systolic, early, and late diastole). GS demonstrated moderate correlation with systolic blood pressure (r = -0.5, P = 0.01), diastolic grade (r = -0.5, P = 0.01), E′ velocity (r = 0.6, P = 0.0001), peak A velocity (r = -0.5, P = 0.004), and LAVI (r = -0.6, P = 0.002). Conclusions: Left atrial dysfunction is evident in stage 3 CKD with associated LA enlargement. This study demonstrates that LA GS and SR were reduced in the CKD group despite similar LAVI in the CKD with HT and HT group. Hence LA GS and SR may be a more sensitive noninvasive tool to detect cardiovascular involvement in CKD

Coronary angiography and angioplasty without onsite cardio-thoracic surgical backup in a new cardiac catheterisation lab : a single-centre experience

Coronary angiography and angioplasty have previously been shown to be performed safely and successfully by experienced staff without onsite cardiothoracic surgery backup. This study aimed to report the performance of a single centre in New South Wales (NSW). Methods and Results: All consecutive patients (n = 812) who underwent angiography and or angioplasty at the cardiac catheterisation lab, between 29 August 2016 and 31 December 2017, at Campbelltown Hospital were evaluated. The lab initially performed angiography only. The angioplasty program commenced on 18 September 2017. Patients with significant coronary artery disease requiring complex angioplasty or coronary artery bypass graft (CABG) were transferred to a nearby tertiary hospital. In total, 527 patients underwent angiography during the angiography only period, and 222 patients underwent angiography with 63 angioplasties during the angioplasty period. Patient demographics included: mean age 64 ± 12 years, mean body mass index 30.6 kg/m2, 64% males, 34% with diabetes, 65% with hypertension, and 50% with dyslipidaemia. Among the procedures, 270 (33%) were performed for non-ST-elevation myocardial infarction (NSTEMI), 68 (8.4%) for unstable angina, three (0.3%) for STEMI, and 471 (58%) for stable coronary heart disease. Vascular access was obtained via radial in 542 patients (67%). A same day discharge program was implemented based on specific safety criteria. Seven patients (0.86%) had minor haematoma at the access site (0.18% radial vs 2.2% femoral, p = 0.007). One patient had localised radial artery dissection, which was managed conservatively. There were no major adverse cardiac events (death, myocardial infarction, major bleeding or stroke), or emergency surgery. Conclusion: Favourable clinical outcomes with minimal complications were experienced during the first year. These results were consistent with previously published data from other NSW centre

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

Cardiac invasive electrophysiology studies with radiofrequency ablation without onsite cardiothoracic surgical back-up in a new cardiac electrophysiology laboratory : single-centre experience

ntroduction: Previous studies of invasive cardiac electrophysiology (EP) and radiofrequency catheter ablation (RFA) concluded that procedures can be safely performed successfully in selected groups of patients, by experienced staff, without on-site cardiothoracic surgery back-up. We aim to report a single centre experience. Methods and results: All consecutive patients (n = 57) who underwent cardiac EP studies and/or RFA at a cardiac EP laboratory, between 12 October 2016 and 13 December 2017 at Campbelltown Hospital in New South Wales, were evaluated. The cardiac EP laboratory was opened in October 2016 with one EP session per week. Patients who require complex RFA procedures such as pulmonary vein isolation for atrial fibrillation and ventricular tachycardia ablation were transferred to a nearby tertiary hospital. Median age was 57 years (interquartile range 39–54 years) and 63% were male. The indications and numbers of invasive EP studies and RFA are shown in the Figure 1. There were no access site complications, no major adverse cardiovascular events (death, stroke, major bleeding, perforation, tamponade, or complete heart block). No patients required emergency surgery. Conclusion: Cardiac EP studies with RFA are safely performed in certain indications for procedures without surgical back-up. Favourable clinical outcomes were obtained without complications during the first year experience. These results are consistent with the current published data