Performance of the New BioMonitor 2-AF Insertable Cardiac Monitoring System: Can Better be Worse?

BACKGROUND: Implantable loop recorders (ILR) are valuable tools for the investigation of patients with suspected arrhythmias. The BioMonitor 2-AF is a novel insertable ILR with enhanced atrial fibrillation (AF) detection algorithm and remote monitoring capability. OBJECTIVE: The objective of this first-in-human study with the BioMonitor 2-AF was to analyze course of P-wave sensing performance and R-wave amplitude, prevalence of false and correctly sensed and classified episodes, and effectiveness of remote monitoring. METHODS: All 19 patients who underwent ILR insertion were included in the BIOTRONIK Home Monitoring® system (BIOTRONIK GmbH, Berlin, Germany). Daily changes in P-wave and R-wave sensing were analyzed over 6 weeks. A breathing test (in- and expiration) was performed in two different body positions at baseline and during a 6-week in-house follow-up to investigate alterations of P-wave and R-wave sensing. RESULTS: R-wave amplitude and the high P-wave visibility (94.4%) remained unchanged during the follow-up period. In most patients both an increase and decrease of R-wave amplitude, and in some cases a complete R-wave vector change (31.6%), was documented during the "breathing test." Change of body position did not alter R-wave sensing amplitude mostly. "Breathing test" and change of body position had no effect on P-wave sensing performance. In 15.8% of the patients, misclassification of episodes as AF or high ventricular rates due to P-wave oversensing occurred. No ILR-related complication occurred. Automatic transmission via BIOTRONIK Home Monitoring® was successful 100% of the time. CONCLUSION: This study demonstrates that the BioMonitor 2-AF is a safe and effective tool for continuous cardiac monitoring.

[Clinical courses and costs for hospitalizations of potentially immunocompromised COVID-19 patients in Germany]. / Klinische Verläufe und Kosten für Hospitalisierungen von COVID-19-Patienten mit potenziell eingeschränktem Immunsystem in Deutschland.

BACKGROUND: Patients at increased risk of inadequate immune response to COVID-19 vaccinations due to their underlying disease or therapy are potentially vulnerable to severe COVID-19 courses. The aim is to assess the population size, clinical courses and hospitalization costs of these patients in Germany. METHODS: This retrospective cohort study is based on extrapolations of a representative sample of statutory health insurance (SHI) claims data from 2020. Clinical COVID-19 courses, hospitalization costs and durations are compared between the insured group at increased risk for inadequate immune response to COVID-19 vaccinations (risk group) and the insured group without this risk. RESULTS: There are approximately 1.82 million SHI-insured individuals in the risk group, of whom an estimated 240 000 insured individuals do not develop a humoral immune response after 3 COVID-19 vaccinations. The risk group shows higher proportions with COVID-19 (relative risk [RR] 1.21; 95 % confidence interval [95 % CI] 1.20-1.23), hospitalizations for COVID-19 (RR 3.40; 95 % CI 3.33-3.48), hospitalizations for COVID-19 with intensive care treatment (RR 1.36; 95 % CI 1.30-1.42), and mortality (RR 5.14; 95 % CI 4.97-5.33) compared with the group without risk. In addition, hospitalizations in the risk group are on average 18 % longer (15.36 days vs. 13.00 days) and 19 % more expensive (12 371 € vs. 10 410 €). Expected hospitalization costs in the risk group are four times greater than in the group without risk (4115 € vs. 1017 €). CONCLUSIONS: The risk group is vulnerable to COVID-19 and requires additional resources in the German hospital sector. This results in a need for further protective measures. Further studies are needed to evaluate the impact of different viral variants, active and passive immunizations, and therapies on clinical COVID-19 courses and their costs.

Retrospective, Observational Analysis on the Impact of SARS-CoV-2 Variant Omicron in Hospitalized Immunocompromised Patients in a German Hospital Network-The VISAGE Study.

AIMS: Endemic SARS-CoV-2 infections still burden the healthcare system and represent a considerable threat to vulnerable patient cohorts, in particular immunocompromised (IC) patients. This study aimed to analyze the in-hospital outcome of IC patients with severe SARS-CoV-2 infection in Germany. METHODS: This retrospective, observational study, analyzed administrative data from inpatient cases (n = 146,324) in 84 German Helios hospitals between 1 January 2022 and 31 December 2022 with regard to in-hospital outcome and health care burden in IC patients during the first 12 months of Omicron dominance. As the primary objective, in-hospital outcomes of patients with COVID-19-related severe acute respiratory infection (SARI) were analyzed by comparing patients with (n = 2037) and without IC diagnoses (n = 14,772). Secondary analyses were conducted on IC patients with (n = 2037) and without COVID-19-related SARI (n = 129,515). A severe in-hospital outcome as a composite endpoint was defined per the WHO definition if one of the following criteria were met: intensive care unit (ICU) treatment, mechanical ventilation (MV), or in-hospital death. RESULTS: In total, 12% of COVID-related SARI cases were IC patients, accounting for 15% of ICU admissions, 15% of MV use, and 16% of deaths, resulting in a higher prevalence of severe in-hospital courses in IC patients developing COVID-19-related SARI compared to non-IC patients (Odds Ratio, OR = 1.4, p < 0.001), based on higher in-hospital mortality (OR = 1.4, p < 0.001), increased need for ICU treatment (OR = 1.3, p < 0.001) and mechanical ventilation (OR = 1.2, p < 0.001). Among IC patients, COVID-19-related SARI profoundly increased the risk for severe courses (OR = 4.0, p < 0.001). CONCLUSIONS: Our findings highlight the vulnerability of IC patients to severe COVID-19. The persistently high prevalence of severe outcomes in these patients in the Omicron era emphasizes the necessity for continuous in-hospital risk assessment and monitoring of IC patients.

Magnetic field-induced interactions between phones containing magnets and cardiovascular implantable electronic devices: Flip it to be safe?

BACKGROUND: Recent case reports and small studies have reported activation of the magnet-sensitive switches in cardiovascular implantable electronic devices (CIEDs) by the new iPhone 12 series, initiating asynchronous pacing in pacemakers and suspension of antitachycardia therapies in implantable cardioverter-defibrillators (ICDs). OBJECTIVE: The purpose of this prospective single-center observational study was to quantify the risk of magnetic field interactions of the iPhone 12 with CIEDs. METHODS: A representative model of each CIED series from all manufacturers was tested ex vivo. Incidence and minimum distance necessary for magnet mode triggering were analyzed in 164 CIED patients with either the front or the back of the phone facing the device. The magnetic field of the iPhone 12 was analyzed using a 3-axis Hall probe. RESULTS: Ex vivo, magnetic interference occurred in 84.6% with the back compared to 46.2% with the front of the iPhone 12 facing the CIED. In vivo, activation of the magnet-sensitive switch occurred in 30 CIED patients (18.3%; 21 pacemaker, 9 ICD) when the iPhone 12 was placed in close proximity over the CIED pocket and the back of the phone was facing the skin. Multiple binary logistic regression analysis identified implantation depth (95% confidence interval 0.02-0.24) as an independent predictor of magnet-sensitive switch activation. CONCLUSION: Magnetic field interactions occur only in close proximity and with precise alignment of the iPhone 12 and CIEDs. It is important to advise CIED patients to not put the iPhone 12 directly on the skin above the CIED. Further recommendations are not necessary.

Wearable cardioverter-defibrillator: friend or foe in suspected myocarditis?

AIM: Wearable cardioverter defibrillator (WCD, LifeVest, and Zoll) therapy has become a useful tool to bridge a temporarily increased risk for sudden cardiac death. However, despite extensive use, there is a lack of evidence whether patients with myocarditis and impaired LVEF may benefit from treatment with a WCD. METHODS AND RESULTS: We conducted a single-centre retrospective observational study analysing patients with a WCD prescribed between September 2015 and April 2020 at our institution. In total, 135 patients were provided with a WCD, amongst these 76 patients (mean age 48.9 ± 13.7 years; 84.2% male) for clinically suspected myocarditis. Based on the results of the endomyocardial biopsy and, where available cardiac magnetic resonance imaging, 39 patients (51.3%) were diagnosed with myocarditis and impaired LVEF and 37 patients (48.7%) with dilated cardiomyopathy (DCM) without evidence of cardiac inflammation. The main immunohistopathological myocarditis subtype was lymphocytic myocarditis in 36 (92.3%) patients, and four patients (10.3%) of this group had an acute myocarditis. Three patients had cardiac sarcoidosis (7.7%). Ventricular tachycardia occurred in seven myocarditis (in total 41 VTs; 85.4% non-sustained) and one DCM patients (in total one non-sustained ventricular tachycardia). Calculated necessary WCD wearing time until ventricular tachycardia occurrence is 86.41 days in myocarditis compared with 6.46 years in DCM patients. CONCLUSIONS: Our data suggest that myocarditis patients may benefit from WCD therapy. However, as our study is not powered for outcome, further randomized studies powered for the outcome morbidity and mortality are necessary.

The effect of iron deficiency on cardiac resynchronization therapy: results from the RIDE-CRT Study.

AIMS: Cardiac resynchronization therapy (CRT) improves functional status, induces reverse left ventricular remodelling, and reduces hospitalization and mortality in patients with symptomatic heart failure, left ventricular systolic dysfunction, and QRS prolongation. However, the impact of iron deficiency on CRT response remains largely unclear. The purpose of the study was to assess the effect of functional and absolute iron deficiency on reverse cardiac remodelling, clinical response, and outcome after CRT implantation. METHODS AND RESULTS: The relation of iron deficiency and cardiac resynchronization therapy response (RIDE-CRT) study is a prospective observational study. We enrolled 77 consecutive CRT recipients (mean age 71.3 ± 10.2 years) with short-term follow-up of 3.3 ± 1.9 months and long-term follow-up of 13.0 ± 3.2 months. Primary endpoints were reverse cardiac remodelling on echocardiography and clinical CRT response, assessed by change in New York Heart Association classification. Echocardiographic CRT response was defined as relative improvement of left ventricular ejection fraction ≥ 20% or left ventricular global longitudinal strain ≥ 20%. Secondary endpoints were hospitalization for heart failure and all-cause mortality (mean follow-up of 29.0 ± 8.4 months). At multivariate analysis, iron deficiency was identified as independent predictor of echocardiographic (hazard ratio 4.97; 95% confidence interval 1.15-21.51; P = 0.03) and clinical non-response to CRT (hazard ratio 4.79; 95% confidence interval 1.30-17.72, P = 0.02). We found a significant linear-by-linear association between CRT response and type of iron deficiency (P = 0.004 for left ventricular ejection fraction improvement, P = 0.02 for left ventricular global longitudinal strain improvement, and P = 0.003 for New York Heart Association response). Iron deficiency was also significantly associated with an increase in all-cause mortality (P = 0.045) but not with heart failure hospitalization. CONCLUSIONS: Iron deficiency is a negative predictor of effective CRT therapy as assessed by reverse cardiac remodelling and clinical response. Assessment of iron substitution might be a relevant treatment target to increase CRT response and outcome in chronic heart failure patients.