Faculty Bibliography

Occult atrial fibrillation (AF) can be the underlying cause for cryptogenic stroke (CS). Implantable loop recorders (ILRs) have become an important tool for long-term arrhythmia monitoring in CS patients. Office-based ILR implantation by nonelectrophysiologist physicians is increasingly common. To report the real world diagnostic yield and accuracy of remote ILR monitoring in high risk CS patients, we retrospectively analyzed 145 consecutive patients with CS who underwent ILR implantation between October 2014 and October 2018 at New York University Langone Health. A certified device technician and an electrophysiologist adjudicated all transmissions. The yield and accuracy of Reveal LINQ Intra Cardiac Monitor (ICM), a fourth generation device, was compared to that of TruRhythm Detection algorithm (fifth generation device). AF was diagnosed in 17 patients (12%) over a mean follow-up of 28 ± 12 months. The median time to diagnosis was 7.4 ± 21.3 months. A total of 1,637 remote transmissions (scheduled- and auto-triggered alerts: 756; patient-triggered: 881) were adjudicated. The positive predictive value for AF episodes in the scheduled interrogations increased from 4% in the Reveal LINQ ICM to 16% in the TruRhythm LINQ. Of 881 patient-triggered transmissions, none were found to be true positive. In the Reveal LINQ ICM, for scheduled transmissions, primary causes of false positive (FP) were atrial ventricular premature complexes (80%). In the TruRhythm LINQ, for scheduled transmissions, primary cause of FP were T-wave over-sensing (87%). In conclusion, the real world diagnostic yield of ILR for patients with CS remains suboptimal, with at least 84% of AF alerts being FP. Patient-riggered events did not correlate with arrhythmia and the necessity of patient triggering in this population should be questioned. Expert interpretation of recordings is critical to assure accurate diagnosis.

BACKGROUND:Increased peak luminal esophageal temperature (LET) is associated with increased risk of esophageal injury following left atrial posterior wall (LAPW) ablation. The magnitude, distribution, and risk factors of LET increase with high power short duration (HPSD) LAPW ablation are not well understood. OBJECTIVE:We aimed to describe the spatial and temporal characteristics of LET changes associated with HPSD LAPW RFA. METHODS:LET was sampled at 20Hz using a 12-point esophageal temperature monitor (CIRCA S-CATH, Circa Scientific, Inc.) in 16 patients undergoing LAPW ablation. Esophageal temperature sensor position and lesion locations were recorded using an electroanatomic mapping system with fluoroscopic integration (CARTO 3, CARTOUNIVU, Biosense Webster, Inc). Point-by-point LAPW ablation was performed at 50W for 6s. The first 20 LAPW lesions were individually analyzed in each patient. RESULTS:LET increase ≥4°C (8 lesions: Max LET 5.8°C), 2-4°C (34 lesions), and 1-2°C (58 lesions) occurred at 9±2 mm, 8±2 mm, and 13±2mm from sensors, respectively. Lesions placed >20mm from a temperature sensor did not result in an LET increase ≥2°C. Temperature resolution to within 1°C of baseline occurred at ∼60s after cessation of RF. Consecutive lesions resulting in additive heating of at least 1°C occurred in 17 lesion pairs with an inter-lesion distance of 9±4mm and inter-lesion time of 21±4s. CONCLUSION/CONCLUSIONS:HPSD LAPW ablation can result in severe esophageal temperature increases. Significant LET increase will be undetected when lesions are >20mm away from a temperature sensor. Additive LET increase was observed with consecutive lesions placed less than 20mm apart within 60s.

INTRODUCTION AND AIMS: Ablation of atrial fibrillation (AF) has evolved rapidly in the decade since its inception. We aimed to review the results of this evolution as reflected in the published literature. METHODS: Publications through 2005 were reviewed, and data included if there was information on the technique used, and follow-up of at least 6 months. RESULTS: More than 23,000 patients met criteria for inclusion. There has been a steady improvement in reported outcomes (P<0.001). Variations on radiofrequency catheter ablation for pulmonary vein isolation result in apparent elimination ("cure") or improvement of AF in 75%, and surgical techniques are even better. CONCLUSIONS: Catheter ablation of AF is now a mainstream procedure. Continuing technical advances are needed to achieve better results with more uniformity and reduced procedure times.

An elevated triglyceride (TG)/high-density lipoprotein (HDL) ratio has been described as a predictor of insulin resistance and cardiovascular events. We evaluated whether a TG/HDL ratio > or = 3.5 was associated with the burden of coronary artery disease (CAD) on cardiac catheterization. A retrospective chart review of 156 consecutive adults presenting to the Montefiore Medical Center Emergency Department with symptoms of unstable angina and no known history of CAD who underwent cardiac catheterization as part of their index hospitalization was performed. TG and HDL data were available in 100 patients within 6 months prior to admission and no more than 24 hours after presentation. A priori, a burden of CAD score was developed. On multivariate analysis, a TG/HDL ratio > or = 3.5 was associated with the burden of CAD (odds ratio, 2.87; 95% confidence interval, 1.03-7.96; p = 0.04). Further study is warranted.