Left Septal Atrial Tachycardias: Electrocardiographic and Electrophysiologic Characterization of a Paraseptal Focus

Left Septal Atrial Tachycardias. Objective: The objective was to characterize the electrocardiographic and electrophysiological features of focal atrial tachycardia (FAT) originating from the left septum (LS). Background: FAT is recognized to occur at predefined anatomic locations rather than randomly throughout the atria. We describe the ECG and EP features of ATs originating from the LS as an important site for apparent perinodal tachycardias. Methods: Nine patients presenting with LS FAT from a consecutive series of 384 underwent EP/RFA for symptomatic FAT. Results: The mean age was 56 ± 12 years; 7 female with symptoms for 36 ± 28 months. P wave morphology (PWM) was negative/positive in lead V1 and across the precordial leads and negative or negative/positive in inferior leads in all patients. Tachycardia was incessant in 6 out of 9 patients with a mean tachycardia cycle length 421 ± 56 milliseconds. His A was ahead of P wave in all patients (mean ?15 ± 5 milliseconds) and earlier than CS proximal (mean 4 ± 9 milliseconds). Successful acute focal ablation achieved at a mean of 31 ± 12 milliseconds ahead of P wave with no recurrences at a mean follow‐up of 30 ± 28 months. Conclusion: Although the left septum is an uncommon site for focal AT an awareness of this location for harboring foci is particularly important when mapping apparently right‐sided septal tachycardias. (J Cardiovasc Electrophysiol, Vol. 24, pp. 413‐418, April 2013)     

Long-Term Clinical Outcomes of Underdosed Direct Oral Anticoagulants in Patients with Atrial Fibrillation and Atrial Flutter

BackgroundAlthough direct oral anticoagulants (DOACs) have been shown to be effective at reducing the risk of stroke in patients with atrial fibrillation/flutter (AF), they are sometimes underdosed off-label to mitigate their associated higher bleeding risk. We sought to evaluate frequency and clinical outcomes of inappropriate underdosing of DOACS in patients with AF.MethodsWe conducted a study of subjects with AF who had a clinical indication for stroke prophylaxis (with a congestive heart failure, hypertension, age ≥75 years, diabetes mellitus, stroke or transient ischemic attack, vascular disease, age 65 to 47 years, sex category [CHA₂DS₂-VASc] of 2 or greater) and were prescribed 1 of the 4 clinically approved DOACs (apixaban, rivaroxaban, dabigatran, or edoxaban). We compared all-cause mortality, composite of stroke and systemic embolism, composite of myocardial infarction (MI), acute coronary syndromes (ACS), and coronary revascularization, and major bleeding between patients appropriately dosed and inappropriately underdosed.ResultsA total of 8125 patients met inclusion criteria, with a mean follow up of 2.2 ± 2 years. Of those, 1724 patients (21.2%) were inappropriately dosed. After adjusting for baseline variables, there was no difference in all-cause mortality, risk of stroke or systemic embolism, International Society on Thrombosis and Haemostasis (ISTH) major bleeding, or composite of myocardial infarction, acute coronary syndromes, or coronary revascularization between patients appropriately dosed and inappropriately underdosed. In subgroup analysis, only apixaban demonstrated an increased incidence all-cause mortality (hazard ratio [HR] 1.24, 95% confidence interval [CI] 1.03-1.49) with inappropriate underdosing. There was no difference in the remaining clinical outcomes noted on subgroup analysis.ConclusionUnderdosing of DOACs did not minimize risk of bleeding, systemic embolization or all-cause mortality in patients with AF. Inappropriate underdosing with apixaban in particular was associated with increased all-cause mortality.     

Animal models for SARS-CoV-2 and SARS-CoV-1 pathogenesis,transmission and therapeutic evaluation

There is a critical need to develop animal models to alleviate vaccine and drug development difficulties against zoonotic viral infections. The coronavirus family, which includes severe acute respiratory syndrome coronavirus 1 and severe acute respiratory syndrome coronavirus 2, crossed the species barrier and infected humans, causing a global outbreak in the 21^st century. Because humans do not have pre-existing immunity against these viral infections and with ethics governing clinical trials, animal models are therefore being used in clinical studies to facilitate drug discovery and testing efficacy of vaccines. The ideal animal models should reflect the viral replication, clinical signs, and pathological responses observed in humans. Different animal species should be tested to establish an appropriate animal model to study the disease pathology, transmission and evaluation of novel vaccine and drug candidates to treat coronavirus disease 2019. In this context, the present review summarizes the recent progress in developing animal models for these two pathogenic viruses and highlights the utility of these models in studying SARS-associated coronavirus diseases.     

Use of ACIST™ contrast injection device in carotid artery stenting in high-surgical-risk patients

ObjectiveThe objective is to see if use of the ACIST? device during carotid stenting would be feasible without an increase in primary end points when compared to historic controls.BackgroundCarotid stenting has been studied as an effective alternative to endarterectomy in high-surgical-risk patients. Traditional angiography involves manual contrast injection. It leads to excess contrast volume and greater fluoroscopy times. The Acist contrast injection device helps with the regulation and lowering of contrast volume.MethodsThis is a consecutive, non-randomized, open-label, multiple-operator-based study. Inclusion criteria were as follows: (a) subject is considered at high risk for carotid endarterectomy, (b) subject requires percutaneous carotid angioplasty and stenting for carotid disease, and (c) subject must be asymptomatic with ≥ 80% stenosis of the internal and/or common carotid artery. The primary end points measured were, death from any cause, myocardial infarction, transient ischemic attack or stroke within 30 days of intervention. Secondary end points were contrast volume and fluoroscopy time.ResultsFour operators in one institution performed interventions from June 2007 to May 2012 on 133 consecutive patients. They were predominantly men (59.4%). The mean age (SD) was 73.64 (7.952) years. Stroke occurred in 3% (N = 4), transient ischemic attack in 0.8% (N = 1) and myocardial infarction in 0.8% (N = 1). Three study subjects died (2.3%). The mean (SD) contrast volume was 121.24 (67.79) mL. The mean (SD) fluoroscopy time was 18.34 (11.31) minutes.ConclusionsThe use of the ACIST? device was feasible in carotid stenting in a high-risk population without an increase in end points when compared to historic controls.     

Lung Scedosporiosis in Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome

A 31-year-old African American woman with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/ AIDS) (recent CD4 count of 66/mm³) presented to the emergency room with a tension pneumothorax that required an emergent chest tube placement. Computed tomography scan showed fungus balls in multiple lung cavities and surrounding infiltrates. The patient showed remarkable improvement with voriconazole suggesting aspergillosis. However, the patient was serologically negative for Aspergillus and other common fungal infections. Because of a persistent air leak, surgical intervention was needed. The histological finding was consistent with invasive mycosis, and cultures were positive for Scedosporium apiospermum. Literature review showed that, among patients with HIV/AIDS, Scedosporium can present from focal localized to systemic disease, is resistant to traditional antifungal agents, and may respond to prompt management with voriconazole.     

Pharmacologic Therapy of Chronic Heart Failure

Over the past 2 decades, investigators have learned more about the pathophysiologic changes that occur in systolic and diastolic dysfunction. Ironically, in some cases, the biologic pathways that have protected the heart during acute dysfunction are the same pathways that cause progressive deleterious effects with chronic activation. In particular, it is the activation of the neurohormonal system that has a significant impact on disease progression. As a result, the neurohormonal system has provided a key target for pharmacologic therapy in patients with heart failure secondary to systolic dysfunction. These targets include the renin-angiotensin-aldosterone system as well as the sympathetic nervous system. Neurohormonal manipulation, however, is often ineffective in the pharmacologic therapy of patients with endstage heart failure, therefore other treatment strategies - including the use of inotropic agents to improve pump function and diuretics to control fluid balance are needed.     

Sexually transmitted diseases in children

Sexually transmitted diseases (STDs) cause considerable morbidity among their victims. This is true even for children. Unfortunately, this aspect has not received due attention and remains a relatively ignored field. We carried out a study of the clinico-epidemiological profile of STDs among the pediatric patients who attended the STD clinic of a tertiary care hospital. Pediatric patients who presented with STDs from January of 1995 to February of 2001 constituted the subject material of this study. A detailed clinical examination and relevant laboratory investigations were carried out in all patients. A total of 15,453 STD patients were seen during this period, out of which 127 were children, giving a prevalence of 0.82% pediatric STD cases. The peak incidence of STDs was seen in the age group of 10-14 years (66.1%). Most of them were illiterate (61.4%) and from low socio-economic backgrounds (70.9%). Notably, 17.3% were from remand homes. The predominant STDs observed among these children were syphilis (25.2%), including six cases of congenital syphilis, vulvo-vaginal candidiasis (11.8%), condyloma-acuminata (14.2%), herpes progenitalis (8.7%) and traumatic lesions (7.9%). Histories or signs of abuse were present in 74% of the patients. Only two cases during the span of the study were HIV positive. Pediatric STDs remain a hidden and neglected problem. Children constituted 0.82% of all STD patients in our series. This may represent only the tip of the iceberg, because several features, including some operational problems, are responsible for underdiagnosis of pediatric STDs. If not treated promptly and adequately, they may result in significant physical and emotional sequelae in children. Thus, it is essential to develop strategies to prevent sexual abuse and to have adequate counselling measures, especially in juvenile delinquents.