High-Resolution Cardiac Magnetic Resonance Imaging Techniques for the Identification of Coronary Microvascular Dysfunction

ObjectivesThis study assessed the ability to identify coronary microvascular dysfunction (CMD) in patients with angina and nonobstructive coronary artery disease (NOCAD) using high-resolution cardiac magnetic resonance (CMR) and hypothesized that quantitative perfusion techniques would have greater accuracy than visual analysis.BackgroundHalf of all patients with angina are found to have NOCAD, while the presence of CMD portends greater morbidity and mortality, it now represents a modifiable therapeutic target. Diagnosis currently requires invasive assessment of coronary blood flow during angiography. With greater reliance on computed tomography coronary angiography as a first-line tool to investigate angina, noninvasive tests for diagnosing CMD warrant validation.MethodsConsecutive patients with angina and NOCAD were enrolled. Intracoronary pressure and flow measurements were acquired during rest and vasodilator-mediated hyperemia. CMR (3-T) was performed and analyzed by visual and quantitative techniques, including calculation of myocardial blood flow (MBF) during hyperemia (stress MBF), transmural myocardial perfusion reserve (MPR: MBF_HYPEREMIA / MBF_REST), and subendocardial MPR (MPR_ENDO). CMD was defined dichotomously as an invasive coronary flow reserve <2.5, with CMR readers blinded to this classification.ResultsA total of 75 patients were enrolled (57 ± 10 years of age, 81% women). Among the quantitative perfusion indices, MPR_ENDO and MPR had the highest accuracy (area under the curve [AUC]: 0.90 and 0.88) with high sensitivity and specificity, respectively, both superior to visual assessment (both p < 0.001). Visual assessment identified CMD with 58% accuracy (41% sensitivity and 83% specificity). Quantitative stress MBF performed similarly to visual analysis (AUC: 0.64 vs. 0.60; p = 0.69).ConclusionsHigh-resolution CMR has good accuracy at detecting CMD but only when analyzed quantitatively. Although omission of rest imaging and stress-only protocols make for quicker scans, this is at the cost of accuracy compared with integrating rest and stress perfusion. Quantitative perfusion CMR has an increasingly important role in the management of patients frequently encountered with angina and NOCAD.     

Diabetic heel ulcer in the Sudan: determinants of outcome

Heel ulceration, on average, costs 1.5 times more than metatarsal ulceration. The aim of this study was to analyze the determinant factors of healing in diabetic patients with heel ulcers and the late outcomes at Jabir Abu Eliz Diabetic Centre Khartoum, Khartoum, Sudan. Data were collected prospectively for 96 of 100 diabetic patients presenting with heel ulcers at the Jabir Abu Eliz Diabetic Centre Khartoum from May 2003 to January 2005. Late outcome was assessed 3 years later (February 2008). Heeling was achieved in one half of the patients (n = 48). In the remaining 48 patients, 22 ended with major lower extremity amputation and 22 were still receiving wound care. A total of 8 patients died, 4 in each group, the healed and unhealed. The most significant determinants of healing using a logistic multivariate regression model, 95% confidence intervals, and odds ratios included a shorter duration of diabetes (p < .009), adequate lower limb perfusion (p < .043), and a superficial foot ulcer (p < .012). Three years later, of the 88 patients who could be traced, 78 were alive and 59 had healed ulcers (7 had died of unrelated causes and 3 of diabetic-related complications), and no additional lower extremity amputation was recorded. Mortality in the series was 18 patients, of whom 14 had undergone a previous lower extremity amputation. Superficial heel ulcers in diabetic patients with a short history of diabetes and with good limb circulation are more likely to heal within an average duration of 25 weeks. At 3 years of follow-up, 75% showed a favorable outcome for ulcer healing, and 22 patients underwent lower extremity amputation (25%), of whom 14 were dead within 3 years.     

An audit of the predictors of outcome in status epilepticus from a resource‐poor country: a comparison with developed countries

Aim. Status epilepticus is a neurological emergency with significant morbidity and mortality. This study describes the clinical profile, treatment, and predictors of outcome of status epilepticus in a tertiary referral centre in a developing country and aims to highlight the similarities and differences from data available from the western world. Methods. A retrospective analysis of data of patients treated for status epilepticus was conducted from prospectively maintained records, between January 2000 and September 2010. The demographic data, clinical profile and investigations (including neuroimaging and EEG), aetiology, treatment, and outcomes were studied and compared with data available from the western world. Results. The analysis included 108 events in 84 patients. A single episode of status epilepticus was treated in 72 patients (86%) and multiple status epilepticus events, ranging from two to six per patient, were managed in 12 patients (14%). Mean age was 24.1±20.3 years and 63% were males. The types of status epilepticus included convulsive status in 98 (90.7%), non‐convulsive status in seven (6.5%), and myoclonic status in three (2.8%). The majority of events (60%) were remote symptomatic, 16% were acute symptomatic, 16% were of unexplained aetiology, and 8% were progressive symptomatic. In 85 events (79%), status epilepticus could be aborted with first and second‐line drugs. The remaining 23 events (21%) progressed to refractory status epilepticus, among which, 13 (56%) were controlled with continuous intravenous midazolam infusion. Case fatality rate was 11%, neurological sequelae were reported in 22%, and 67% returned to baseline. Acute symptomatic status, older age, altered sensorium at the time of admission, and delayed hospitalisation were predictors of poor outcome. Conclusions. Aetiology was the most important determinant of outcome of status epilepticus, as in reports from the western world, with remote symptomatic aetiology secondary to gliosis being the most common. Treatment delay was frequent and adversely affected the outcome.     

Benzene's toxicity: a consolidated short review of human and animal studies

A large population of humans is exposed to benzene from various occupational and environmental sources. Benzene is an established human and animal carcinogen. Exposure to benzene has been associated with leukaemia in humans and several types of malignancies in animals. The exact mechanism of benzene-induced toxicity is poorly understood. It is believed that benzene exerts its adverse effects by metabolic activation to toxic metabolites. Certain benzene metabolites are genotoxic and mutagenic. This consolidated short-review is composed of human and animal studies to summarize the adverse effects of benzene with special reference to molecular mechanisms involved in benzene-induced toxicity.     

Spontaneous pneumomediastinum mimicking acute pericarditis

ST elevations on electrocardiogram (ECG) have a broad differential diagnosis that can vary from benign to more ominous pathologies. These include early repolarization, coronary vasospasm, acute pericarditis, ST‐elevation myocardial infarction, ventricular aneurysms, and dissecting aneurysm of the aorta reaching the pericardium. ST‐segment changes may also provide a clue to the presence of spontaneous pneumomediastinum (SPM). These ECG changes are seldom reported in literature. We describe two SPM cases with concomitant pneumopericardium that closely mimicked acute pericarditis with a deceptive clinical spectrum.