Detection of Obstructive Coronary Artery Disease Using Peak Systolic Global Longitudinal Strain Derived by Two-Dimensional Speckle-Tracking: A Systematic Review and Meta-Analysis.

BACKGROUND: Global longitudinal strain (GLS) is well validated and has important applications in contemporary clinical practice. The aim of this analysis was to evaluate the accuracy of resting peak GLS in the diagnosis of obstructive coronary artery disease (CAD). METHODS: A systematic literature search was performed through July 2015 using four databases. Data were extracted independently by two authors and correlated before analyses. Using a random-effect model, the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and summary area under the curve for GLS were estimated with their respective 95% CIs. RESULTS: Screening of 1,669 articles yielded 10 studies with 1,385 patients appropriate for inclusion in the analysis. The mean age and left ventricular ejection fraction were 59.9 years and 61.1%. On the whole, 54.9% and 20.9% of the patients had hypertension and diabetes, respectively. Overall, abnormal GLS detected moderate to severe CAD with a pooled sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 74.4%, 72.1%, 2.9, and 0.35 respectively. The area under the curve and diagnostic odds ratio were 0.81 and 8.5. The mean values of GLS for those with and without CAD were -16.5% (95% CI, -15.8% to -17.3%) and -19.7% (95% CI, -18.8% to -20.7%), respectively. Subgroup analyses for patients with severe CAD and normal left ventricular ejection fractions yielded similar results. CONCLUSION: Current evidence supports the use of GLS in the detection of moderate to severe obstructive CAD in symptomatic patients. GLS may complement existing diagnostic algorithms and act as an early adjunctive marker of cardiac ischemia.

High Intensity Interval versus Moderate Intensity Continuous Training in Patients with Coronary Artery Disease: A Meta-analysis of Physiological and Clinical Parameters.

INTRODUCTION: Exercise-based cardiac rehabilitation for patients with coronary artery disease (CAD) significantly improves their outcome, although the optimal mode of exercise training remains undetermined. Previous analyses have been constrained by small sample sizes and a limited focus on clinical parameters. Further, results from previous studies have been contradicted by a recently published large RCT. METHOD: We performed a meta-analysis of published randomised controlled trials to compare high intensity interval training (HIIT) and moderate intensity continuous training (MCT) in their ability to improve patients' aerobic exercise capacity (VO2peak) and various cardiovascular risk factors. We included patients with established coronary artery disease without or without impaired ejection fraction. RESULTS: Ten studies with 472 patients were included for analyses (218 HIIT, 254 MCT). Overall, HIIT was associated with a more pronounced incremental gain in participants' mean VO2peak when compared with MCT (+1.78mL/kg/min, 95% CI: 0.45-3.11). Moderate intensity continuous training however was associated with a more marked decline in patients' mean resting heart rate (-1.8/min, 95% CI: 0.71-2.89) and body weight (-0.48kg, 95% CI: 0.15-0.81). No significant differences were noted in the level of glucose, triglyceride and HDL at the end of exercise program between the two groups. CONCLUSION: High intensity interval training improves the mean VO2peak in patients with CAD more than MCT, although MCT was associated with a more pronounced numerical decline in patients' resting heart rate and body weight. The underlying mechanisms and clinical relevance of these results are uncertain, and remain a potential focus for future studies.

Heart-type fatty acid binding protein in early diagnosis of myocardial infarction in the era of high-sensitivity troponin: a systematic review and meta-analysis.

INTRODUCTION: Heart-type fatty acid binding protein (HT FABP) is an emerging biomarker of ischaemic myocardial necrosis. While previous studies have demonstrated its additive value when compared to contemporary troponin assays in the diagnosis of acute myocardial infarction (AMI), its utility in the era of high-sensitivity troponin (hsTn) assays remains undetermined. METHODOLOGY: A systematic review and meta-analysis of relevant studies was performed comparing the diagnostic performance of HT FABP both alone and in conjunction with hsTn in the early diagnosis and exclusion of AMI. RESULTS: A systematic literature search yielded eight eligible studies including 3395 patients. Of these, 716 patients (21.1%) were eventually diagnosed with AMI. The pooled sensitivity and specificity for hsTn on admission was 82.5% (95% confidence interval [CI]: 79.8-85.0%) and 89.7% (95% CI: 88.7-90.6%), respectively, while the area under the curve (AUC) for the summary receiver operating characteristics (ROC) curve is 0.92 (SE 0.02). While the pooled specificity (84.6%, 95% CI: 83.2-85.9%) of admission HT FABP is similar to hsTn for the early diagnosis of AMI (P = 0.07), its pooled sensitivity (63.5%, 95% CI: 59.9-67.1%, P < 0.001) is significantly worse. Accordingly, the AUC of the summary ROC curve for HT FABP (0.79, SE 0.03) is inferior to hsTn (P < 0.0001). The addition of HT FABP to hsTn resulted in no improvement in the sensitivity (P = 0.058) and worsened the specificity (P = 0.001) in the early diagnosis of AMI compared to hsTn alone. CONCLUSION: HT FABP does not appear to improve the diagnostic accuracy of hsTn, and consequently its routine use currently cannot not be recommended.

Recommended changes to diagnostic criteria for gestational diabetes: impact on workload.

BACKGROUND: Gestational diabetes mellitus (GDM) is recognised as a significant problem in pregnancy. Changes to GDM diagnostic criteria have been proposed following analysis of data from the Hyperglycemia and Adverse Pregnancy Outcome (HAPO) study. We sought to assess the impact on the workload for GDM management in Australia that would occur if these changes were adopted. AIM: To assess the impact on health professional workload, specifically management of the number of additional women who would be diagnosed with GDM, should the newly recommended diagnostic criteria be adopted in Australia. METHODS: We analysed oral glucose tolerance test results undertaken in pregnant women at two large pathology services in South West and Northern Sydney. We calculated GDM rates using current Australasian Diabetes in Pregnancy Society (ADIPS) Australian Criteria and the rates using the proposed new criteria. RESULTS: These workload data compare ADIPS and proposed International Association of Diabetes and Pregnancy Study Groups Criteria. In a high-risk population examined in two time periods, the estimated increase in workload was 29.0% (based on November 2005 to August 2007 data) and 31.9% (based on September 2007 to August 2009 data). Data from Northern Sydney indicated a 21.7% increased workload (based on September 1998 to July 2009 data). CONCLUSIONS: If the newly recommended changes to the diagnostic criteria for GDM are implemented in Australia, we may need to change the way we currently structure our services to manage GDM, to cope with the workload impact of the significantly increased number of women who would require management. In some units this change will be substantial.