Karuppiah Arunachalam

A novel method of standardized myocardial infarction in aged rabbits

The incidence of both myocardial infarction (MI) and sudden cardiac death increases with age. Here, we describe the development of a minimally invasive large animal model of MI that can be applied to young or aged animals. We demonstrate that rabbit coronary anatomy is highly variable, more so than described in previous literature. In this work, we categorize the coronary pattern of 37 young rabbits and 64 aged rabbits. Aged rabbits had a higher degree of branching from the left main coronary artery. Standardizing the model across age cohorts required a new approach, targeting an area of myocardium rather than a specific vessel. Here, we present a method for achieving a reproducible infarct size, one that yielded a consistent scar encompassing ~30% of the apical left ventricular free wall. The models consistency allowed for more valid comparisons of MI sequelae between age cohorts.NEW & NOTEWORTHY This study describes the coronary angiographic imaging of young and aged rabbits. We developed and improved a novel minimally invasive approach for coil embolization that targets a specific area of myocardium and yielded a consistent scar encompassing ~30% of the left ventricular free wall of young and aged rabbit hearts.

Bloodstream infections due to extended-spectrum β-lactamase-producing Enterobacteriaceae among patients with malignancy: a systematic review and meta-analysis

Extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-PE) are an increasing cause of resistant infections among patients with malignancy. This study sought to estimate the prevalence of bloodstream infections (BSIs) caused by ESBL-PE in this population and to examine regional and temporal differences. The PubMed and EMBASE databases (to 30 April 2016) were searched to identify studies reporting ESBL-PE BSI rates among patients with malignancies. Of 593 non-duplicate reports, 22 studies providing data on 5650 BSI cases satisfied the inclusion criteria. Among all BSIs the pooled prevalence of ESBL-PE was 11% (95% CI 8-15%) and among Gram-negative BSIs it was 21% (95% CI 16-27%). Among patients with haematological malignancies, the pooled ESBL-PE prevalence was 11% (95% CI 8-15%), whereas no studies providing specific data on patients with solid tumours were identified. Stratifying per geographic region, the pooled prevalence was 7% each in Europe (95% CI 5-11%), the Eastern Mediterranean region (95% CI 4-11%) and South America (95% CI 2-14%), 10% in the Western Pacific region (95% CI 4-19%) and 30% in Southeast Asia (95% CI 18-44%). Importantly, there was a 7.1% annual increase in the ESBL-PE incidence (P = 0.004). Overall, ca. 1 in 10 BSIs in patients with malignancy is caused by ESBL-PE and in some areas this rate can be as high as 1 in 3 cases. Additionally, the incidence of these resistant infections is rising. These findings should be considered when selecting empirical antimicrobial therapy and should prompt strict adherence to antimicrobial stewardship.

Readmission Among Hospitalized Patients: An Important Health Care Issue

“Hospital Readmissions Following Physician Call System Change: A Comparison of Concentrated and Distributed Schedules” is an interesting research article by Yarnell et al published in the July issue of The American Journal of Medicine. It was interesting in terms of assessing the changes in the physician call system that affect the quality of health care. But I would like to emphasize a few important details that are important in terms of outcome and future research studies. It would be more informative if reasons for readmissions and type of readmissions were addressed. The reason for readmission is important, as it will help quantify the burden of distribution among medical conditions and facilitate improvement in patient care. Planned readmissions are another important cause for readmission, and lack of information on them may falsely increase the total number of readmissions. Rehospitalization also helps to assess the

PVCs, PVC-Induced Cardiomyopathy, and the Role of Catheter Ablation

Premature ventricular contractions (PVCs) are common arrhythmias noticed in the clinical setting because of premature depolarization of the ventricular myocytes. Although often thought to be reflective of underlying disease rather than intrinsically harmful, PVCs have recently been linked with worse outcomes in patients without significant cardiac disease. Long-term exposure to a high PVC burden can lead to the development of PVC-induced cardiomyopathy. The pathogenesis of this condition is poorly understood at the current time. Many studies have suggested that catheter ablation of these PVCs may result in reversal of the PVC-induced cardiomyopathy. This article will go over the natural history of PVCs and PVC-induced cardiomyopathy, as well as review the current literature on the role of catheter ablation in treating PVC-induced cardiomyopathy.

Coronary Sinus Anatomy and its Importance-evidence based Review

Coronary sinus is the largest cardiac venous channel and its increasingly used during electrophysiological procedures like LV pacing, biventricular ICD lead placement and ablation. There are few other novel procedures under research including stem cell delivery in case of ischemic myocardium. Coronary sinus anatomy, its variations in tributaries and the clinical implications are discussed in this review article.