Epicardial access for the treatment of cardiac arrhythmias

Since the introduction of percutaneous epicardial access for the purpose of mapping and ablation of cardiac arrhythmias, this technique has become an important adjunct and at times the preferred approach to treat certain cardiac arrhythmias. In addition, this approach is currently also being considered for a number of other cardiovascular applications such as epicardial pacing, left atrial appendage ligature occlusion, etc. The focus of this review is to discuss relevant aspects of pericardial anatomy, and various methods of epicardial access.     

The Modified Ablation Guided by Ibutilide Use in Chronic Atrial Fibrillation (MAGIC-AF) Study: clinical background and study design

The MAGIC‐AF Study. Background: Beyond pulmonary vein isolation (PVI), adjuvant ablation at the sites of complex fractionated atrial electrograms (CFAE) has been shown to improve the long‐term success of catheter ablation of persistent atrial fibrillation (AF). However, this approach often requires extensive ablation due to the widespread distribution of CFAE within the left atrium. An optimal strategy would identify areas of CFAE which, when selectively targeted with ablation, result in AF termination with an acceptable long‐term freedom from AF. It is possible that the intraprocedural administration of an antiarrhythmic drug may help accomplish this. Objective: The Modified Ablation Guided by Ibutilide Use in Chronic AF (MAGIC‐AF) Study is an international multicenter prospective randomized double‐blinded clinical trial assessing the utility of the intraprocedural administration of 0.25 mg of intravenous ibutilide before performing CFAE ablation. The primary efficacy endpoint of this study will be the freedom from AF at 1 year after a single procedure off antiarrhythmic agents. Safety endpoints will include procedural and radiofrequency ablation time as well as overall procedural complication rate. Methods: Patients undergoing a first ever catheter ablation procedure for persistent AF will be included. Individuals with hypertrophic cardiomyopathy, complex congenital heart disease including atrial septal defects, and ejection fraction <35% will be excluded from the study. All patients will first undergo PVI. Those patients who remain in AF will then be randomized in a 1:1 fashion to receive either 0.25 mg intravenous ibutilide or saline placebo followed by a CFAE based ablation strategy. Two hundred randomized patients will be enrolled in this study—100 in each study arm. Conclusion: The MAGIC‐AF study will assess the utility of a combined pharmaco‐ablative strategy in patients with persistent AF undergoing a CFAE based ablation strategy.     

Deep learning early warning system for embryo culture conditions and embryologist performance in the ART laboratory

Staff competency is a crucial component of the in vitro fertilization (IVF) laboratory quality management system because it impacts clinical outcomes and informs the key performance indicators (KPIs) used to continuously monitor and assess culture conditions. Contemporary quality control and assurance in the IVF lab can be automated (collect, store, retrieve, and analyze), to elevate quality control and assurance beyond the cursory monthly review. Here we demonstrate that statistical KPI monitoring systems for individual embryologist performance and culture conditions can be detected by artificial intelligence systems to provide systemic, early detection of adverse outcomes, and identify clinically relevant shifts in pregnancy rates, providing critical validation for two statistical process controls proposed in the Vienna Consensus Document; intracytoplasmic sperm injection (ICSI) fertilization rate and day 3 embryo quality.

     

Use of a Food and Drug Administration-Approved Type 1 Diabetes Mellitus Simulator to Evaluate and Optimize a Proportional-Integral-Derivative Controller

Background

Clinical studies have shown that the Medtronic proportional-integral-derivative (PID) control with insulin feedback (IFB) provides stable 24 h glucose control, but with high postprandial glucose. We coupled this algorithm to a Food and Drug Administration-approved type 1 diabetes mellitus simulator to determine whether a proportional-derivative controller with preprogrammed basal rates (PD_BASAL) would have better performance.

Methods

We performed simulation studies on 10 adult subjects to (1) obtain the basal profiles for the PD_BASAL controller; (2) define the pharmacokinetic/pharmacodynamic profile used to effect IFB, (3) optimize the PID and PD_BASAL control parameters, (4) evaluate improvements obtained with IFB, and (5) develop a method to simulate changes in insulin sensitivity and assess the ability of each algorithm to respond to such changes.

Results

PD_BASAL control significantly reduced peak postprandial glucose [252 (standard error = 11) versus 279 (14) mg/dl; p < .001] and increased nadir glucose [102 (3) versus 92 (3) mg/dl; p < .001] compared with PID control (both implemented with IFB). However, with PD_BASAL control, fasting glucose remained elevated following a 30% decrease in insulin sensitivity [156 (6) mg/dl; different from the target of 110 mg/dl; p < .001] and remained below target following a 30% increase in insulin sensitivity [84 (2) mg/dl; p < .001]. In both cases, PID control returned glucose levels to target.

Conclusions

PD_BASAL provides better postprandial glucose control than PID but is not appropriate for subjects whose basal requirements change with insulin sensitivity. Simulations used to compare different control strategies should assess this variability.