Catheter Ablation of Left Ventricular Summit Arrhythmias from Adjacent Anatomic Vantage Points

Idiopathic ventricular arrhythmias (VA), particularly left ventricular outflow tract (LVOT) VA accounts for up to 10% of all VAs referred for ablative therapy. In addition to being infrequent, its intricate anatomy and its pathophysiology make catheter ablation (CA) of these arrhythmias a challenge even for experts. In this scenario, detailed right ventricular outflow tract as well as LVOT electroanatomic mapping including epicardial mapping are essential. In this article, we will emphasize our approach toward the CA technique used for LVOT VA, particularly IVS and/or LVS VA originating from intramural foci, along with its acute and long-term efficacy and safety.

Fluoroless Catheter Ablation of Left Ventricular Summit Arrhythmias: A Step-by-Step Approach

Prolonged use of fluoroscopy during catheter ablation (CA) of arrhythmias is associated with a significant exposure to ionizing radiation and risk of orthopedic injuries given the need for heavy protective equipment. CA of ventricular arrhythmias (VAs) arising from the left ventricular (LV) summit is challenging, requiring a vast knowledge of the intricate cardiac anatomy of this area and careful imaging delineation of the different anatomical structures, which is frequently performed using fluoroscopic guidance. Certain techniques, including pericardial mapping and ablation, use of intracoronary wires, and mapping and ablation inside the coronary venous system have been proposed, further prolonging fluoroscopy time. Fluoroless CA procedures are feasible with currently available technology and appear to have similar safety and efficacy outcomes compared with conventional techniques. To successfully perform fluoroless CA of LV summit arrhythmias, it is important to be fully acquainted with intracardiac echocardiography (ICE) imaging and electroanatomic mapping (EAM). We will describe our approach to perform fluoroless CA in LV summit VAs.

T-wave inversion as a manifestation of COVID-19 infection: a case series

Purpose

Cardiac involvement with COVID-19 infection has become evident by elevated troponin, cardiac arrhythmias, ST segment elevation, myocarditis, fulminant heart failure, and sudden cardiac death. We aimed to describe the association of COVID-19 and T-wave inversion (TWI) in a large case series.

Methods

We conducted an observational, retrospective study of confirmed COVID-19 cases with at least one electrocardiogram (ECG) in a large hospital in New York City (March 23, 2020–April 23, 2020). Patients with new TWI or pseudonormalization were further analyzed. Mortality and the need for invasive mechanical ventilation were the main outcomes.

Results

A total of 3225 patients were screened; 195 (6%) were selected for further analysis: 181 with TWI and 14 with T-wave pseudonormalization. Mean age was 66 ± 7 years; 51% were male. TWI were more commonly noted in the lateral (71%), followed by anterior (64%), inferior (57%), and septal (26%) leads. A total of 44 patients (23%) had elevated troponin. A total of 50 patients died (26%). Mortality rates of 35%, and 52% were observed in patients with diffuse TWI, and elevated troponin, respectively. Mortality rate of 80% was observed in patients with both elevated troponin and diffuse TWI. Additionally, 30% of the entire cohort and 58% of patients with elevated troponin required invasive mechanical ventilation.

Conclusion

Our study demonstrates that new TWI is a relatively common finding in COVID-19 patients. Importantly, our findings suggest that new TWI or T-wave pseudonormalization, particularly with elevated troponin, was associated with higher rates of mechanical ventilation and in-hospital mortality.

Supplementary Information

The online version of this article (10.1007/s10840-020-00896-7) contains supplementary material, which is available to authorized users.

Endovascular management of inferior vena cava filter thrombotic occlusion

Objective Inferior vena cava occlusion is a potentially life-threatening complication related to caval filters. We present our experience with filter-induced inferior vena cava occlusion in order to assess the feasibility, safety, and effectiveness of endovascular management. Methods A retrospective review of all patients undergoing inferior vena cava filter placement over a 60-month study period was performed. From this cohort, a total of 10 cases of inferior vena cava occlusion after filter placement were identified. Demographics, clinical data, procedures, and outcomes were extracted. Patients were followed to the last clinic visit or until they died. Results One-hundred eighty filters were placed by our group practice during the study period. Of those, a total of 10 patients were identified. Overall, there were 7 males; the mean age was 57.1 years (25-78 years). The median time between inferior vena cava filter placement and filter occlusion was 105 days (range 5-4745 days). All patients were clinically symptomatic at the time of their presentation. Nine out of 10 patients were successfully managed endovascularly. Trellis™-8 thrombectomy was the most common endovascular strategy performed ( n = 9). Four patients had balloon angioplasty, two of those with stent placement for chronically occluded inferior vena cava/iliac veins. No thromboembolic complications developed during a median follow-up period of 233 days (range 4-1083 days). Conclusions Endovascular management of inferior vena cava occlusion is feasible, safe, and effective in decreasing thrombus burden in the presence of an inferior vena cava filter. Further studies evaluating long-term inferior vena cava patency and optimal surveillance regimen after endovascular management of filter-related inferior vena cava occlusion are warranted.

Simultaneous coking and dealumination of zeolite H-ZSM-5 during the transformation of chloromethane into olefins

Chloromethane conversion into light olefins leads to distinct deactivation pathways in zeolite H-ZSM-5 compounded with bentonite and α-Al₂O₃ as binder and filler.