A 21-year-old female patient visited our hospital for febrile sensation, coughing, sputum, diarrhoea, and shortness of breath during the coronavirus disease 2019 (COVID-19) outbreak in Daegu, South Korea. Nasopharyngeal swab was positive for COVID-19. Troponin I level was 1.26 ng/mL (<0.3 ng/mL) and NT-proBNP was 1929 pg/mL (<125 pg/mL). The chest radiograph revealed a multifocal consolidation on both lung fields and cardiomegaly (Panel A). Electrocardiography showed non-specific intraventricular conduction delay and multiple premature ventricular complexes (Panel B). Echocardiography showed severe left ventricular (LV) systolic dysfunction ( Supplementary material online , Videos S1–S3). A chest computed tomography (CT) revealed a multifocal consolidation and ground-glass opacification in both lungs in the lower lobe and a peripheral dominant distribution (Panel C). On the cardiac CT, the coronary arteries were normal (Panels D–G), and the myocardium was hypertrophied due to oedema combined with a subendocardial perfusion defect on the lateral left ventricle (Panel N). Cardiac magnetic resonance imaging (MRI) revealed a diffuse high signal intensity (SI) in the LV myocardium on T2 short tau inversion recovery image (Panels H–J; SI ratio of myocardium over skeletal muscle = 2.2), and myocardial wall thickening (LV mass index: 111.3 g/m²), which suggests myocardial wall oedema. On mapping sequence, native T1 (Figure 1K–M; mid-septum, 1431 ms; lateral wall, 1453 ms, reference value ∼1150 ms) and extracellular volume (Panels P–R; mid-septum, 29.7%; lateral wall, 61%; reference value ∼25%) values were diffusely increased (Panel O). Extensive transmural late gadolinium enhancement was noted (Panels S–U). Myocarditis combined with COVID-19 was confirmed by multimodality imaging.

Background - COVID-19 has led to over 1 million deaths worldwide and has been associated with cardiac complications including cardiac arrhythmias. The incidence and pathophysiology of these manifestations remain elusive. In this worldwide survey of patients hospitalized with COVID-19 who developed cardiac arrhythmias, we describe clinical characteristics associated with various arrhythmias, as well as global differences in modulations of routine electrophysiology practice during the pandemic. Methods - We conducted a retrospective analysis of patients hospitalized with COVID-19 infection worldwide with and without incident cardiac arrhythmias. Patients with documented atrial fibrillation (AF), atrial flutter (AFL), supraventricular tachycardia (SVT), non-sustained or sustained ventricular tachycardia (VT), ventricular fibrillation (VF), atrioventricular block (AVB), or marked sinus bradycardia (HR<40bpm) were classified as having arrhythmia. De-identified data was provided by each institution and analyzed. Results - Data was collected for 4,526 patients across 4 continents and 12 countries, 827 of whom had an arrhythmia. Cardiac comorbidities were common in patients with arrhythmia: 69% had hypertension, 42% diabetes mellitus, 30% had heart failure and 24% coronary artery disease. Most had no prior history of arrhythmia. Of those who did develop an arrhythmia, the majority (81.8%) developed atrial arrhythmias, 20.7% developed ventricular arrhythmias, and 22.6% had bradyarrhythmia. Regional differences suggested a lower incidence of AF in Asia compared to other continents (34% vs. 63%). Most patients in in North America and Europe received hydroxychloroquine, though the frequency of hydroxychloroquine therapy was constant across arrhythmia types. Forty-three percent of patients who developed arrhythmia were mechanically ventilated and 51% survived to hospital discharge. Many institutions reported drastic decreases in electrophysiology procedures performed. Conclusions - Cardiac arrhythmias are common and associated with high morbidity and mortality among patients hospitalized with COVID-19 infection. There were significant regional variations in the types of arrhythmias and treatment approaches.

Background and Objectives Nonvitamin K antagonist oral anticoagulants (NOACs) require stricter medication adherence. We investigated the NOACs adherence in real-world practice. Methods We screened all patients in our cardiology department the day before their outpatient appointment, over a 5-month period. We enrolled 719 consecutive patients who were taking NOACs for atrial fibrillation. The patients were contacted by phone or text to bring the remnant pills with them without any information why. Adherence was measured by the percentage of prescribed doses taken (PDT) (number of doses taken/number of doses expected to be taken from the last prescription × 100 [%]) and the Morisky Medication Adherence Scale (MMAS)-8. Results All 4 NOACs (apixaban 47.8%, dabigatran 21.2%, rivaroxaban 18.4%, and edoxaban 12.6%) were prescribed. The mean duration that the patients had been taking NOACs was 7.2 ± 5.7 months. The PDT was 95.4 ± 9.1% in the once-daily dosing group and 93.4 ± 12.7% in the twice-daily group, and the difference was statistically significant (p = 0.017). The mean MMAS was 2.6 ± 0.8. The proportion of patients with a PDT < 80% was 7.8%. They had a significantly higher MMAS than the PDT ≥ 80% group (3.4 vs. 2.5; p = 0.000). Conclusion Most patients who were taking NOACs had excellent adherence regardless of the dosing frequency. An MMAS ≥ 3 could be used as a simple screening tool for a poor NOAC adherence.

Purpose: The exact correlation between the baseline left atrial (LA) volume (LAV) and atrial fibrillation (AF) radiofrequency catheter ablation (RFCA) outcomes and changes to the LA after AF RFCA has not yet been fully understood. We sought to evaluate the serial changes in the LAV and LA function after RFCA using 3D echocardiography. Methods: Consecutive patients who received RFCA of paroxysmal (PAF) or persistent AF (PeAF) at our center between January 2013 and March 2016 were included. Real-time 3D apical full-volume images were acquired, and a 3D volumetric assessment was performed using an automated three-beat averaging method. The LAV index (LAVI) was calculated and the LA ejection fraction (LAEF) was calculated as [LAVmax − LAVmin]/LAVmax. Results: Ninety-nine total patients were enrolled, and the mean age was 58.0 ± 8.2 years and 75 (74.7%) were male. There were 59 (59.6%) PAF patients and the remaining 40 (40.4%) had PeAF. AF recurred in 5 of 59 (8.5%) PAF and in 10 of 40 (25%) PeAF patients. The LAVImax increased on 1 day, decreased at 3 months, and then increased again at 1 year but was lower than that at baseline. The LAEF changes were similar to the volume changes but were more prominent in PeAF than PAF patients. The baseline 3D LAVImax was an independent predictor of AF recurrence after RFCA and the cut-off value was 44.13 ml/m². Conclusion: In our study, even after 3 months of scar formation due to ablation, structural remodeling of the LA continued. The changes were more prominent in the non-recurrent, PeAF patients.

Introduction: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) catheter ablation. However, a PVI alone has been considered insufficient for persistent AF. This study aimed to evaluate the efficacy of persistent AF ablation targeting complex fractionated atrial electrogram (CFAE) areas within low voltage zones identified by high-resolution mapping in addition to the PVI. Methods: We randomized 50 patients (mean age 58.4 ± 9.5 years old, 86.0% males) with persistent AF to a PVI + CFAE group and PVI only group in a 1:1 ratio. CFAE and voltage mapping was performed simultaneously using a Pentaray Catheter with the CARTO3 CONFIDENSE module (Biosense Webster, CA, USA). The PVI + CFAE group, in addition to the PVI, underwent ablation targeting low voltage areas (<0.5 mV during AF) containing CFAEs. Results: The mean persistent AF duration was 24.0 ± 23.1 months and mean left atrial dimension 4.9 ± 0.5 cm. In the PVI + CFAE group, AF converted to atrial tachycardia (AT) or sinus rhythm in 15 patients (60%) during the procedure. The PVI + CFAE group had a higher 1-year AF free survival (84.0% PVI + CFAE vs 44.0 PVI only, P = .006) without antiarrhythmic drugs. However, there was no difference in the AF/AT free survival (60.0% PVI + CFAE vs 40.0% PVI only, P = .329). Conclusion: Persistent AF ablation targeting CFAE areas within low voltage zones using high-density voltage mapping had a higher AF free survival than a PVI only. Although recurrence with AT was frequent in the PVI+CFAE group, the sinus rhythm maintenance rate after redo procedures was 76%.