Browsing by Author "Van Heerden, B. B."

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    99mTc-MIBI stress-rest myocardial perfusion scintigraphy in patients with complete left bundle branch block
    (2001) Ellmann, A.; Van Heerden, P. D. R.; Van Heerden, B. B.; Klopper, J. F.
    Background. Patients with complete left bundle branch block (LBBB) often show a false-positive ischaemic pattern in the interventricular septum on thallium-201 (201Tl) stress-rest myocardial perfusion scintigraphy. Equivocal results have been reported with technetium-99m labelled hexakis-methoxyisobutyl isonitrile (99mTc-MIBI) in such patients. The aim of this retrospective study was to determine the effect of LBBB on the septal uptake of 99mTc-MIBI during stress-rest single photon emission computed tomography (SPECT) scintigraphy. Methods. We studied 75 consecutive patients with LBBB, referred for 99mTc-MIBI stress-rest SPECT. Studies were evaluated by visual analysis using a semi-quantitative grading technique. In all patients with abnormal septal segments, the presence or absence of ischaemic heart disease was confirmed either clinically or by means of angiographical examination. Results. Forty-three patients (57.3%) had completely normal studies. Only 15 (20%) had septal abnormalities (11 with reversible and 4 with fixed defects), while 17 patients (22.7%) had abnormal segments in areas other than the interventricular septum. Except for 1 patient lost to follow-up, ischaemic heart disease was confirmed in all the patients with septal changes. Conclusion. We conclude that 99mTc-MIBI is more specific than 201Tl for identifying ischaemic heart disease in the presence of LBBB.
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    Die effek van heparien-geinduseerde styging in vrye plasmatiroksien op die hartritme na miokardiale infarksie
    (Health and Medical Publishing Group (HMPG), 1985-12) Van Heerden, B. B.; Klopper, J. F.; Weich, H. F. H.; Van Heerden, P. D. R.
    It is well known that an acute myocardial infarction is accompanied by a rise in levels of plasma free fatty acids (FFA), which may lead to a subsequent increase in cardiac arrhythmias. Administration of heparin to patients after an acute myocardial infarction gives rise to an increase both in plasma FFA levels and plasma free thyroxine levels. If administered without a fatty meal the rise in FFA is not accompanied by an increase in arrhythmias. The effect of the heparin-induced rise in plasma free thyroxine on cardiac rhythm has never been investigated. The aim of the present study was to investigate a possible arrhythmic effect of a heparin induced increase in plasma free thyroxine in a group of patients with acute myocardial infarction. We were able to confirm a significant heparin-induced rise in plasma free thyroxine levels, as measured by the effective thyroxine ratio. Although a slightly significant increase in ventricular premature beats could be demonstrated after heparin administration when using the Wilcoxon rank sum test for statistical analysis (but not when the paired t-test was utilized), no significant correlation with free thyroxine levels could be found. Heparin administration to patients suffering from myocardial infarction seems to be safe in terms of a possible arrhythmic effect.
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    Interrogating patient-centredness in undergraduate medical education using an integrated behaviour model
    (Taylor & Francis Group, 2017) Archer, E.; Bitzer, E.; Van Heerden, B. B.
    Background: Patient-centredness, an approach that puts the patient at the centre of the consultation, thus focusing on patients instead of on his/her diseases, has been identified by most medical schools as a desired core competence of their graduates. Despite some curriculum initiatives, medical students often display a lack of patient-centredness upon graduation. This bears reason for concern and it was thus deemed important to explore possible factors that influence the teaching and learning of patient-centredness in an undergraduate medical curriculum. The article suggests a framework that can assist programme developers to conceptualise the teaching and learning of patient-centredness across an undergraduate curriculum. Methods: A qualitative exploratory case study design was used for the study with final-year medical students. Themes of meaning were deduced from the data by employing components of an Integrated Behavior Model (IBM) of Fishbein. Results: The findings of the study revealed that seven factors play a role: background characteristics of students, attitudinal factors, subjective norms (the hidden curriculum), student self-efficacy, acquired skills and knowledge, the environment or context within which patient-centredness is taught and learnt, as well as assessment of learning. Conclusions: Patient-centredness is a complex construct and authors often write about only one of its components. This paper attempts to consider the total undergraduate medical curriculum students are exposed to when they learn about being patient-centred. The teaching and learning of such a multidimensional construct require a comprehensive approach in order to be effective and the IBM seems to be a useful and applicable theoretical model to apply.
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    Making use of an existing questionnaire to measure patient-centred attitudes in undergraduate medical students : a case study
    (Health & Medical Publishing Group, 2014-09) Archer, E.; Bezuidenhout, J.; Kidd, M.; Van Heerden, B. B.
    Background. Patient-centred care is widely acknowledged as important to achieve improved patient outcomes in healthcare. Therefore, it is vital that medical schools should foster this attitude in their students. Studies report that students are becoming less patient-centred in the period between entry to medical school and graduation. Objective. To determine the shift in attitude towards patient-centredness in a group of South African undergraduate medical students. Simultaneously, the reliability and validity of the Patient-Practitioner Orientation Scale (PPOS) in our context were measured. Methods. A cross-sectional survey was undertaken by asking all the medical students from year 1 to year 6 to complete the PPOS. The mean PPOS score for each cohort was calculated using SPSS for Windows. Reliability and validity testing was conducted using Cronbach’s alpha and confirmatory and exploratory factor analysis. Results. The average return rate across the 6 years of study was 81%. The results indicated low initial scores on the PPOS and a decrease in scores over the years of study, with the most dramatic drop being from year 1 to year 2. The PPOS showed poor validity and reliability in our context. Conclusion. The study appears to indicate the same decrease in patient-centredness in our students as has been shown in other studies using this tool. However, the low reliability and validity of the PPOS in our environment means that the result should be interpreted with caution. Factors such as our medical students’ not having had first-hand experience of the doctor-patient relationship and second-language issues may play a role. It is recommended that the PPOS not be used in our context without further exploration of the factors contributing to this loss of reliability and validity.
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    South African medical schools : current state of selection criteria and medical students’ demographic profile
    (Health & Medical Publishing Group, 2016-01) Van der Merwe, L. J.; Van Zyl, G. J.; St. Clair Gibson, A.; Viljoen, M.; Iputo, J. E.; Mammen, M.; Chitha, W.; Perez, A. M.; Hartman, N.; Fonn, S.; Green-Thompson, L.; Ayo-Ysuf, O. A.; Botha, G. C.; Manning, D.; Botha, S. J.; Hift, R.; Retief, P.; Van Heerden, B. B.; Volmink, J.
    ENGLISH SUMMARY : Background: Selection of medical students at South African (SA) medical schools must promote equitable and fair access to students from all population groups, while ensuring optimal student throughput and success, and training future healthcare practitioners who will fulfil the needs of the local society. In keeping with international practices, a variety of academic and non-academic measures are used to select applicants for medical training programmes in SA medical schools. Objectives: To provide an overview of the selection procedures used by all eight medical schools in SA, and the student demographics (race and gender) at these medical schools, and to determine to what extent collective practices are achieving the goals of student diversity and inclusivity. Methods: A retrospective, quantitative, descriptive study design was used. All eight medical schools in SA provided information regarding selection criteria, selection procedures, and student demographics (race and gender). Descriptive analysis of data was done by calculating frequencies and percentages of the variables measured. Results: Medical schools in SA make use of academic and non-academic criteria in their selection processes. The latter include indices of socioeconomic disadvantage. Most undergraduate medical students in SA are black (38.7%), followed by white (33.0%), coloured (13.4%) and Indian/Asian (13.6%). The majority of students are female (62.2%). The number of black students is still proportionately lower than in the general population, while other groups are overrepresented. Conclusion: Selection policies for undergraduate medical programmes aimed at redress should be continued and further refined, along with the provision of support to ensure student success.
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    Die waarde van speldgatkollimator-opnames in die flikkergrafiese diagnose van werwelpatologie
    (Health & Medical Publishing Group, 1989) Van Heerden, B. B.; Prins, M. J.
    Recent findings suggested a possible role for pinhole collimator scintigraphy to differentiate between metastases, infection and fractures of the vertebrae. The aim of this study was to verify these findings and to ascertain whether we could identify any other specific scintigraphic patterns. The study group consisted of 58 patients. A metastatic pattern was obtained in 18 patients, while 16 showed the compression fracture pattern, 3 the tuberculosis pattern and 1 the pyogenic infection pattern. The study was considered normal in 4 patients and showed a nonspecific pattern in 4. Sensitivity was 85% for the metastatic pattern and 83% for the compression fracture pattern. Specificity was 94% for both patterns. Unique new patterns were identified in Paget's disease and in degenerative disease of the vertebrae (12 patients). Pinhole scintigraphy of the vertebrae is a valuable aid for detecting specific diseases of the vertebrae. Our findings suggest a valuable new role for skeletal scintigraphy, improving the specificity and obviating, in most cases of vertebral disease, the need for additional investigations.