Prevalence, Management, and Outcome of Atrial Fibrillation and Other Supraventricular Arrhythmias in COVID-19 Patients.

COVID-19 mainly affects the respiratory system but has been correlated with cardiovascular manifestations such as myocarditis, heart failure, acute coronary syndromes, and arrhythmias. Cardiac arrhythmias are the second most frequent complication affecting about 30% of patients. Several mechanisms may lead to an increased risk of cardiac arrhythmias during COVID-19 infection, ranging from direct myocardial damage to extracardiac involvement. The aim of this review is to describe the role of COVID-19 in the pathogenesis of cardiac arrhythmias and provide a comprehensive guidance for their monitoring and management.

Incidence of Device-Related Thrombosis in Watchman Patients Undergoing a Genotype-Guided Antithrombotic Strategy.

OBJECTIVES: This study sought to report the incidence of device-related thrombosis (DRT) and thromboembolic (TE) events when an alternative to clopidogrel is prescribed in loss-of-function (LOF) allele carriers of the cytochrome P450 2C19 (CYP2C19) gene. BACKGROUND: LOF polymorphisms of the CYP2C19 gene are associated with reduced hepatic bioactivation of clopidogrel. METHODS: A total of 1,002 Watchman patients were included. Six hundred forty-five patients underwent CYP2C19 genetic testing; among patients with clopidogrel resistance, clopidogrel was replaced by either prasugrel (pilot cohort) or half dose direct oral anticoagulant ([DOAC]/Group 1), both in combination with aspirin. We compared the incidence of DRT/TE events among genotyped patients and a control group which received standard dual antiplatelet therapy (DAPT) (Group 2; n = 357). All reported events occurred during a timeframe between 45- and 180-day follow-up transesophageal echocardiograms, when the 2 different antithrombotic strategies (genotype-guided vs standard DAPT) were adopted. RESULTS: In the pilot cohort (n = 244), bleeding events occurred in 10.2% of patients who received aspirin plus prasugrel, leading to early discontinuation of the prasugrel-based protocol. DOAC Group 1 patients (n = 401), 25.7% were reduced metabolizers, and clopidogrel was replaced by half dose direct oral anticoagulant. DRT was documented in 1 (0.2%) patient of Group 1 and 7 (1.96%) patients of Group 2 (log-rank P = 0.021). The composite endpoint of DRT/TE events was significantly lower among patients receiving a genotype-guided antithrombotic strategy (0.75% vs 3.10%; log-rank P = 0.017). CONCLUSIONS: In Watchman patients, a genotype-based antithrombotic strategy with aspirin plus half dose DOAC in reduced clopidogrel metabolizers was superior to standard DAPT with respect to DRT/TE events.

Does periprocedural anticoagulation management of atrial fibrillation affect the prevalence of silent thromboembolic lesion detected by diffusion cerebral magnetic resonance imaging in patients undergoing radiofrequency atrial fibrillation ablation with open irrigated catheters? Results from a prospective multicenter study.

BACKGROUND: Silent cerebral ischemia (SCI) has been reported in 14% of cases after catheter ablation of atrial fibrillation (AF) with radiofrequency (RF) energy and discontinuation of warfarin before AF ablation procedures. OBJECTIVE: The purpose of this study was to determine whether periprocedural anticoagulation management affects the incidence of SCI after RF ablation using an open irrigated catheter. METHODS: Consecutive patients undergoing RF ablation for AF without warfarin discontinuation and receiving heparin bolus before transseptal catheterization (group I, n = 146) were compared with a group of patients who had protocol deviation in terms of maintaining the therapeutic preprocedural international normalized ratio (patients with subtherapeutic INR) and/or failure to receive pretransseptal heparin bolus infusion and/or ≥2 consecutive ACT measurements <300 seconds (noncompliant population, group II, n = 134) and with a group of patients undergoing RF ablation with warfarin discontinuation bridged with low molecular weight heparin (group III, n = 148). All patients underwent preablation and postablation (within 48 hours) diffusion magnetic resonance imaging. RESULTS: SCI was detected in 2% of patients (3/146) in group I, 7% (10/134) in group II, and 14% (21/148) in group III (P <.001). "Therapeutic INR" was strongly associated with a lower prevalence of postprocedural silent cerebral ischemia (SCI). Multivariable analysis demonstrated nonparoxysmal AF (odds ratio 3.8, 95% confidence interval 1.5-9.7, P = .005) and noncompliance to protocol (odds ratio 2.8, 95% confidence interval 1.5-5.1, P <.001] to be significant predictors of ischemic events. CONCLUSION: Strict adherence to an anticoagulation protocol significantly reduces the prevalence of SCI after catheter ablation of AF with RF energy.

Assessment of temperature, proximity, and course of the esophagus during radiofrequency ablation within the left atrium.

BACKGROUND: Left atrioesophageal fistula is a devastating complication of atrial fibrillation ablation. There is no standard approach for avoiding this complication, which is caused by thermal injury during ablation. The objectives of this study were to evaluate the course of the esophagus and the temperature within the esophagus during pulmonary vein antrum isolation (PVAI) and correlate these data with esophagus tissue damage. METHODS AND RESULTS: Eight-one patients presenting for PVAI underwent esophagus evaluation that included temperature probe placement. Esophagus course was obtained with computed tomography, 3D imaging (NAVX), or intracardiac echocardiography. For each lesion, the power, catheter and esophagus temperature, location, and presence of microbubbles were recorded. Lesion location and esophagus course were defined with 6 predetermined left atrial anatomic segments. Endoscopy evaluated tissue changes during and after PVAI. Of 81 patients, the esophagus coursed near the right pulmonary veins in 23 (28.4%), left pulmonary veins in 31 (38.3%), and mid-posterior wall in 27 (33%). Esophagus temperature was significantly higher during left atrial lesions along its course than with lesions elsewhere (38.9+/-1.4 degrees C, 36.8+/-0.5 degrees C, P<0.01). Lesions that generated microbubbles had higher esophagus temperatures than those without (39.3+/-1.5 degrees C, 38.5+/-0.9 degrees C, P<0.01). Power was not predictive of esophagus temperatures. Distance between the esophagus and left atrium was 4.4+/-1.2 mm. CONCLUSIONS: Lesions near the course of the esophagus that generated microbubbles significantly increased esophagus temperature compared with lesions that did not. Power did not correlate with esophagus temperatures. Esophagus variability makes the avoidance of lesions along its course difficult. Rather than avoiding posterior lesions, emphasis could be placed on better esophagus monitoring for creation of safer lesions.

Usefulness of intracardiac Doppler assessment of left atrial function immediately post-pulmonary vein antrum isolation to predict short-term recurrence of atrial fibrillation.

Doppler assessments of pulmonary venous (PV) and left atrial appendage flows are useful surrogates of left atrial (LA) function, but it is unknown if these can predict atrial fibrillation (AF) recurrence after pulmonary vein antrum isolation. We compared Doppler surrogates of LA function immediately after pulmonary vein antrum isolation in patients with AF recurrence versus matched patients without recurrence. Patients with a 6-month recurrence had significantly lower LA appendage peak emptying velocity (19 +/- 10 vs 29 +/- 11 cm/s) and lower peak PV systolic wave velocity (36 +/- 17 vs 46 +/- 22 cm/s) compared with those without, suggesting that intracardiac Doppler assessment of LA function after AF ablation predicts AF recurrence.