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BACKGROUND: Studies determining the reliability of the World Heart Federation (WHF) anterior mitral valve leaflet (AMVL) measurement are limited by the introduction of bias in their test-retest analyses. This study sought to determine the reliability of the current AMVL measurement while controlling for systematic bias. METHODS: Retrospective analysis of echocardiographic data from 16 patients with previous acute rheumatic fever was performed. Included in this study was an optimized cine loop of the mitral valve (MV) [reader-optimized measurement (ROM]) in the parasternal long-axis view and an optimized still image of the MV obtained from the same cine loop [specialist-optimized image (SOI)]. Each still image and associated cine loop was quadruplicated and randomized to determine intra- and inter-rater agreement and quantify the impact of zoom on AMVL measurement. RESULTS: Specialist-optimized image without zoom reflected the highest degree of agreement in both cohorts with an ICC of 0.29 and 0.46. The agreement in ROM images without zoom was ICC of 0.23 and 0.45. The addition of zoom to SOI decreased agreement further to an ICC of 0.20 and 0.36. The setting associated with the poorest agreement profile was ROI with zoom with an ICC of 0.13 and 0.34, respectively. The intra-rater agreement between readers in both cohorts was moderate across all settings with an ICC ranging between 0.64 and 0.86. CONCLUSIONS: The WHF AMVL measurement is only moderately repeatable within readers and demonstrates poor reproducibility that was not improved by the addition of a zoom-optimized protocol. Given our study findings, we cannot advocate the current WHF AMVL measurement as a reliable assessment for RHD.
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Insuficiencia de la Válvula Mitral , Cardiopatía Reumática , Humanos , Válvula Mitral/diagnóstico por imagen , Reproducibilidad de los Resultados , Estudios Retrospectivos , Cardiopatía Reumática/diagnóstico por imagenRESUMEN
Aims: The World Heart Federation (WHF) criteria identify a large borderline rheumatic heart disease (RHD) category that has hampered the implementation of population-based screening. Inter-scallop separations (ISS) of the posterior mitral valve leaflet, a recently described normal variant of the mitral valve, appears to be an important cause of mild mitral regurgitation (MR) leading to misclassification of cases as WHF 'borderline RHD'. This study aims to report the findings of the Echo in Africa project, a large-scale RHD screening project in South Africa and determine what proportion of borderline cases would be re-classified as normal if there were a systematic identification of ISS-related MR. Methods and results: A prospective cross-sectional study of underserved secondary schools in the Western Cape was conducted. Participants underwent a screening study with a handheld (HH) ultrasound device. Children with an abnormal HH study were re-evaluated with a portable laptop echocardiography machine. A mechanistic evaluation was applied in cases with isolated WHF 'pathological' MR (WHF 'borderline RHD'). A total of 5255 participants (mean age 15± years) were screened. A total of 3439 (65.8%) were female. Forty-nine cases of WHF 'definite RHD' [9.1 cases/1000 (95% confidence interval, CI, 6.8-12.1 cases/1000)] and 104 cases of WHF 'borderline RHD' [19.5 cases/1000 (95% CI, 16.0-23.7 cases/1000)] were identified. Inter-scallop separations-related MR was the underlying mechanism of MR in 48/68 cases classified as WHF 'borderline RHD' with isolated WHF 'pathological' MR (70.5%). Conclusion: In a real-world, large-scale screening project, the adoption of a mechanistic evaluation based on the systematic identification of ISS-related MR markedly reduced the number of WHF 'screen-positive' cases misclassified as WHF 'borderline RHD'. Implementing strategies that reduce this misclassification could reduce the cost- and labour burden on large-scale RHD screening programmes.
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INTRODUCTION: International guidance suggests that injury-associated haemorrhagic shock should be resuscitated using blood products. However, in low- and middle-income countries resuscitation emphasises the use of crystalloids - mainly due to poor access to blood products. This study aimed to estimate the amount of blood loss from serious injury in relation to available emergency blood products at a secondary-level, public Cape Town hospital. METHODS: This retrospective, cross-sectional study included all injured patients cared for in the resuscitation area of Khayelitsha Hospital's emergency centre over a fourteen-week period. Injuries were coded using the Abbreviated Injury Scale, which was then used to estimate blood loss for each patient using an algorithm from the Trauma Audit Research Network. Descriptive statistics were used to describe blood volume lost and blood units required to replace losses greater than 15% circulating blood volume. Four units of emergency blood are stored in a dedicated blood fridge in the emergency centre. Platelets and fresh plasma are not available. RESULTS: A total of 389 injury events were enrolled of which 93 were excluded due to absent clinic data. The mean age was 29 (±10)â¯years. We estimated a median of one unit of blood requirement per week or weekend, up to a maximum of eight or six units, respectively. Most patients (nâ¯=â¯275, 94%) did not have sufficient injury to warrant transfusion. Overall, one person would require a transfusion for every 15 persons with a moderate to serious injury. CONCLUSION: The volume of available emergency blood appears inadequate for injury care, and doesn't consider the need for other causes of acute haemorrhage (e.g. gastric, gynaecological, etc.). Furthermore, lack of other blood components (i.e. plasma and platelets) presents a challenge in this low-resourced setting. Further research is required to determine the appropriate management of injury-associated haemorrhage from a resource and budget perspective.
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INTRODUCTION: Intentional self-poisoning is a significant part of the toxicological burden experienced by emergency centres. The aim of this study was to describe all adults presenting with intentional self-poisoning over a six-month period to the resuscitation unit of Khayelitsha Hospital, Cape Town. METHODS: Adult patients with a diagnosis of intentional self-poisoning between 1 November 2014 and 30 April 2015 were retrospectively analysed after eligible patients were obtained from the Khayelitsha Hospital Emergency Centre database. Missing data and variables not initially captured in the database were retrospectively collected by means of a chart review. Summary statistics were used to describe all variables. RESULTS: A total of 192 patients were included in the analysis. The mean age was 27.3â¯years with the majority being female (nâ¯=â¯132, 68.8%). HIV-infection was a comorbidity in 39 (20.3%) patients, while 13 (6.8%) previously attempted suicide. Presentations per day of the week were almost equally distributed while most patients presented after conventional office hours (nâ¯=â¯152, 79.2%), were transported from home (nâ¯=â¯124, 64.6%) and arrived by ambulance (nâ¯=â¯126, 65.6%). Patients spend a median time of 3h37m in the resuscitation unit (interquartile range 1â¯h 45â¯m-7â¯h 00â¯m; maximum 65â¯h 49â¯m). Patient acuity on admission was mostly low according to both the Triage Early Warning Score (non-urgent nâ¯=â¯100, 52.1%) and the Poison Severity Score (minor severity nâ¯=â¯107, 55.7%). Pharmaceuticals were the most common type of toxin ingested (261/343, 76.1%), with paracetamol the most frequently ingested toxin (nâ¯=â¯48, 25.0%). Eleven patients (5.7%) were intubated, 27 (14.1%) received N-acetylcysteine, and 18 (9.4%) received benzodiazepines. Fourteen (7.3%) patients were transferred to a higher level of care and four deaths (2%) were reported. DISCUSSION: Intentional self-poisoning patients place a significant burden on emergency centres. The high percentage of low-grade acuity patients managed in a high-acuity area is of concern and should be investigated further.