Vascular calcification in South African dialysis patients: ethnic variation, prevalence, detection and haemodynamic correlates.

AIM: Studies from the US have shown little effect of ethnicity on vascular calcification in dialysis patients. This has not been examined in the multi-ethnic population of South Africa where genetic and environmental differences may exist. We assessed the extent and severity of vascular calcification in South African dialysis patients according to race and known risk factors. We further evaluated the association of abdominal aorta calcification with coronary artery calcification. METHOD: Seventy-five CKD-5D patients and 20 healthy controls were enrolled consecutively. All subjects underwent chest computed tomography for coronary calcium score and abdominal X-ray for abdominal aorta calcium score. Ambulatory blood pressure monitoring was generated via radial artery applanation tonometry. RESULTS: Coronary calcification was present in 38.6% of patients and was associated with age and prior cardiovascular disease on multivariate analyses. The median coronary calcium score in black patients was 0 (IQR 0) and 66 in non-Blacks (IQR 383, P < 0.001); controls had a coronary calcium score of 0 (IQR 0). Black race remained a significant negative predictor for coronary calcification after adjustment, prevalence ratio = 0.14 and 95% confidence interval (CI): 0.0-0.53. Vascular calcification was not associated with any ambulatory blood pressure parameter. Using receiver operator characteristic curves, an abdominal aorta calcification score of ≥1 showed an area under the curve of 0.83 to predict a coronary calcium score ≥ 10. CONCLUSION: Black race appears to protect from vascular calcification in South African CKD-5D patients and this warrants further study regarding the underlying mechanism. The abdominal X-ray is a useful screening tool for coronary calcification.

Proptosis with Increased Orbital Fat in an Obese Patient.

Computational tomography (CT) is a well-documented modality in the workup of proptosis. We present a case of proptosis due to increased orbital fat in an obese patient. We review the literature to discuss the most likely causes of increased orbital fat, and we discuss the utility of CT imaging in assessing this pathology.

Review of cardiovascular magnetic resonance in human immunodeficiency virus-associated cardiovascular disease.

Despite ongoing advances in the treatment of patients with human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS), they remain a major global public health concern conferring an increased risk of morbidity and mortality in affected individuals. This is, in part, because of the widespread dysfunction imposed by HIV and its treatment on the cardiovascular system, including the myocardium, valvular apparatus, pericardium and coronary, pulmonary and peripheral vasculature. In recent times, cardiovascular magnetic resonance (CMR) imaging has emerged as the gold standard tool for assessment of a variety of indications, allowing comprehensive characterisation of functional, morphological, metabolic and haemodynamic sequelae of several cardiovascular pathologies. Furthermore, continued advancement in imaging techniques has yielded novel insights into the underlying pathophysiology and guides future therapeutic strategies. In this article, we review the various clinical phenotypes of HIV-associated cardiovascular disease and highlight the utility of CMR in their assessment.

Diagnosing cardiac disease during pregnancy: imaging modalities.

Pregnant women with known or suspected cardiovascular disease (CVD) often require cardiovascular imaging during pregnancy. The accepted maximum limit of ionising radiation exposure to the foetus during pregnancy is a cumulative dose of 5 rad. Concerns related to imaging modalities that involve ionising radiation include teratogenesis, mutagenesis and childhood malignancy. Importantly, no single imaging study approaches this cautionary dose of 5 rad (50 mSv or 50 mGy). Diagnostic imaging procedures that may be used in pregnancy include chest radiography, fluoroscopy, echocardiography, invasive angiography, cardiovascular computed tomography, computed tomographic pulmonary angiography, cardiovascular magnetic resonance (CMR) and nuclear techniques. Echocardiography and CMR appear to be completely safe in pregnancy and are not associated with any adverse foetal effects, provided there are no general contra-indications to MR imaging. Concerns related to safety of imaging tests must be balanced against the importance of accurate diagnosis and thorough assessment of the pathological condition. Decisions about imaging in pregnancy are premised on understanding the physiology of pregnancy, understanding basic concepts of ionising radiation, the clinical manifestations of existent CVD in pregnancy and features of new CVD. The cardiologist/physician must understand the indications for and limitations of, and the potential harmful effects of each test during pregnancy. Current evidence suggests that a single cardiovascular radiological study during pregnancy is safe and should be undertaken at all times when clinically justified. In this article, the different imaging modalities are reviewed in terms of how they work, how safe they are and what their clinical utility in pregnancy is. Furthermore, the safety of contrast agents in pregnancy is also reviewed.

Two cases of cardiac sarcoidosis in pregnant women with supraventricular arrhythmia.

We present two cases of cardiac sarcoidosis whose first presentation was in pregnancy. All findings confirmed the diagnosis of sarcoidosis with cardiac involvement in both patients. The first patient, a 37-year-old, presented with dizziness and atrial fibrillation at 16 weeks' gestation. Echocardiography revealed thickened interventricular septum with a speckled pattern. Cardiac MRI after delivery showed myocardial oedema/inflammation corresponding with the same regions with early enhancement and epicardial delayed enhancement in the basal to mid-inferoseptal and basal anterior left ventricular myocardial segments. Transbronchial biopsy revealed histology of scanty fragments of inflamed bronchial mucosa. The second patient, a 31-year-old, was 17 weeks pregnant when she presented with daily palpitations and shortness of breath. She had prolonged episodes of supraventricular tachycardia. Echocardiography revealed a speckled septal and right ventricular wall pattern. Cardiac MRI after delivery showed basal and mid-ventricular mesocardial and epicardial enhancement, most compatible with sarcoidosis.

Vascular calcification is not associated with increased ambulatory central aortic systolic pressure in prevalent dialysis patients.

INTRODUCTION: Central aortic systolic pressure (CASP) strongly predicts cardiovascular outcomes. We undertook to measure ambulatory CASP in 74 prevalent dialysis patients using the BPro (HealthStats, Singapore) device. We also determined whether coronary or abdominal aortic calcification was associated with changes in CASP and whether interdialytic CASP predicted ambulatory measurement. METHODS: All patients underwent computed tomography for coronary calcium score, lateral abdominal radiography for aortic calcium score, echocardiography for left ventricular mass index and ambulatory blood pressure measurement using BPro calibrated to brachial blood pressure. HealthStats was able to convert standard BPro SOFT(®) data into ambulatory CASP. RESULTS: Ambulatory CASP was not different in those without and with coronary (137.6 vs 141.8 mmHg, respectively, p = 0.6) or aortic (136.6 vs 145.6 mmHg, respectively, p = 0.2) calcification. Furthermore, when expressed as a percentage of brachial systolic blood pressure to control for peripheral blood pressure, any difference in CASP was abolished: CASP: brachial systolic blood pressure ratio = 0.9 across all categories regardless of the presence of coronary or aortic calcification (p = 0.2 and 0.4, respectively). Supporting this finding, left ventricular mass index was also not different in those with or without vascular calcification (p = 0.7 and 0.8 for coronary and aortic calcification). Inter-dialytic office blood pressure and CASP correlated excellently with ambulatory measurements (r = 0.9 for both). CONCLUSION: Vascular calcification was not associated with changes in ambulatory central aortic systolic pressure in this cohort of prevalent dialysis patients. Inter-dialytic blood pressure and CASP correlated very well with ambulatory measurement.