No abstract

Background: The most commonly used parameter of cardiac function in the chronic kidney disease (CKD) patient is ejection fraction (EF), using transthoracic echocardiography (TTE). EF is a highly load-dependent measurement, which varies considerably in CKD patients undergoing haemodialysis. The aim of this pilot study was to evaluate a novel measure of myocardial function, left ventricular twist, which is defined as the 'wringing action of the heart', using speckletracking echocardiography in CKD patients before and after haemodialysis. Methods: Twenty-six patients were recruited from the Chris Hani Baragwanath Hospital haemodialysis unit. TTE was performed according to a detailed standardised protocol before and after a single haemodialysis session. Echocardiography was also performed on 26 age-and gendermatched healthy subjects. Results: The mean age of the control versus CKD group was 44 ± 11.4 and 43.4 ± 12.2 years, respectively; 46% were male. Apical rotation was diminished in CKD patients compared to controls (4.83 ± 2.3 vs 6.31 ± 1.6 °; p = 0.01) despite no difference in EF (61.7 ± 6.2 vs 58.8 ± 13; p = 0.68). There were no differences in the components of twist: apical rotation, basal rotation and net twist before and after dialysis, despite an increase in EF (58.8 ± 13.7 vs 61.2 ± 13.6; p = 0.02) following dialysis. Conclusion: Unlike EF, the components of twist are relatively independent of changes in haemodynamic load seen during dialysis. The decrease in apical rotation may represent an early marker of cardiac pathology in the late-stage CKD patient.

Background: Acute kidney injury (AKI) occurs commonly within the hospital setting and is associated with a high rate of morbidity and mortality. Factors such as social, economic and ethical dilemmas are closely associated with initiation of dialysis in the public health sector. Methods: A retrospective review of 324 patients presenting with kidney failure who were initiated on acute dialysis at the Chris Hani Baragwanath Hospital was carried out over a 2-year period from July 2009 to June 2011. Results: The mean age at presentation was 40 ± 13 years; 57% of patients were male and 92% were Black. HIV positivity occurred in 26% of patients. The leading indications for acute dialysis included decompensated chronic kidney disease (38.9%), acute tubular necrosis (ATN) (38.3%), HIV-related kidney disease (13.6%), malaria (5.7%), pregnancy-related kidney disease (7.4%) and glomerulonephritis (7.4%). ATN was the predominant cause of AKI in HIV-positive patients. The overall renal recovery rate was 31%, and the overall mortality rate was 23%. About 44.6% of patients had chronic consequences, with 23% being transferred to chronic renal replacement therapy (RRT) and 21.6% transferred to renal outpatients (ROPD) with cessation of dialysis; 1.4% were lost to follow-up. While HIV-positive patients had a better renal recovery rate compared to HIV-negative patients (36% versus 26%; p < 0.0001), they had a higher mortality rate compared to their HIV-negative counterparts (34% versus 19%; p < 0.0001). Conclusion: AKI remains a common presentation that often requires dialysis, a precious resource in an already overburdened health system, and occurs at similar rates in HIV-positive and HIV-negative patients. The underlying aetiology of AKI at Chris Hani Baragwanath resembles that of other developing countries with ATN, malaria, sepsis and pregnancy-induced kidney injury amongst the leading causes. High mortality rates were observed in patients with ATN, in both HIV-positive and HIV-negative patients.