We show that particularly weak German banks used the European Central Bank’s very long-term refinancing operations (VLTROs) to evergreen exposures to zombie firms. Zombie firms that obtain more credit after the introduction of the VLTROs had a substantially elevated subsequent default probability. This suggests that either positive private information did not materialize or the decision to engage in zombie lending was not driven by any such private information. At the time of loan extension, banks that resort to the VLTRO report lower borrower-specific probabilities of default, reduce loan loss provisions and lower their credit standards relative to banks who lend to the same firm but have not resorted to the VLTRO. Zombie firms, which obtained additional funding from banks relying to a larger extent on VLTRO funding, in turn increase their accounts payable and advance payments received from downstream and upstream firms. This suggests that suppliers relying on banks’ lending decisions as a signal about borrowers’ credit quality might be misled by banks’ zombie lending to extend more trade credit to zombie firms exposing suppliers to elevated contagion risk.
Control problems frequently arise in scientific and industrial applications, where the objective is to steer a dynamical system from an initial state to a desired target state. Recent advances in deep learning and automatic differentiation have made it increasingly practical to apply these methods to control problems. This paper provides an accessible overview of how neural networks and modern machine learning frameworks can be used to parameterize control inputs for both discrete-time and continuous-time systems, encompassing deterministic and stochastic dynamics. Applications are highlighted across multiple domains, including biology, engineering, physics, and medicine. For continuous-time dynamical systems, neural ordinary differential equations (neural ODEs) provide a useful approach to parameterizing control inputs, while in discrete-time settings, custom control-input parameterizations can be implemented and optimized using automatic differentiation. Overall, the methods presented offer practical solutions for control tasks that are computationally demanding or analytically intractable, making them valuable for complex real-world applications.
BACKGROUND:Patients undergoing orthotopic transcatheter tricuspid valve replacement (TTVR) frequently present with a cardiac implantable electronic device (CIED) lead traversing the tricuspid valve. OBJECTIVES:This study sought to investigate the clinical, procedural, and lead-related outcomes of orthotopic TTVR in patients with transvalvular CIED leads. METHODS:All consecutive patients enrolled in the multicenter TRIPLACE (Global Multicenter Registry on Transcatheter Tricuspid Valve Replacement) registry were included for analysis. Patients were stratified based on the presence of a CIED lead traversing the tricuspid valve. Changes in lead function parameters were assessed after TTVR in a subset of these patients who had pacemaker lead parameter data recorded. Lead failure was defined as structural or electrical malfunction requiring new lead or CIED insertion. RESULTS:Among 395 patients, 104 (26.3%) had transvalvular CIED leads. Procedural success, symptomatic improvement, and 30-day mortality were comparable between those with and without CIED. Patients with CIED leads had lower rates of mild or less residual tricuspid regurgitation (82.6% vs 91.4%; P < 0.041) and higher rates of moderate or greater paravalvular leak (17.1% vs 7.1%; P < 0.017). Lead failure occurred in 5.8% over a median follow-up time of 183 days, with modest changes in pacing thresholds. No significant increase in adverse events or mortality was observed at 30 days. CONCLUSIONS:Orthotopic TTVR in patients with transvalvular CIED leads can be safely and effectively performed with low rates of lead failure. Significant paravalvular leak and residual tricuspid regurgitation is more common with a jailed lead. These patients require close CIED follow-up with alternative pacing strategies in place, particularly when pacing dependent. (Global Multicenter Registry on Transcatheter TRIcuspid Valve RePLACEment [TRIPLACE]; NCT06033274).
AIMS:Atrial fibrillation (AF) ablation by pulmonary vein isolation (PVI) and left atrial appendage closure (LAAC) are increasingly performed as standalone procedures. Given that PVI and LAAC share the same access route, a combined approach of pulsed field ablation (PFA)-based PVI and LAAC might be beneficial. The COCONUT study focused on safety, efficacy, and outcomes combining PVI by PFA with LAAC in one procedure. METHODS:This is a retrospective, multinational registry study. The primary endpoints were the following: (1) primary safety endpoint: serious adverse events; and (2) primary efficacy endpoint: success of PVI and LAA closure defined as the ability to isolate all pulmonary veins and the successful closure of the LAA. For secondary endpoints, peri-procedural data and follow-up data were collected. RESULTS:A total of 155 patients from 22 centres of nine European countries were treated by concomitant pentaspline catheter PFA-based PVI and LAAC. The mean CHA2DS2-VA score was 3.1 ± 1.4. The primary efficacy endpoint was achieved at 97.4% with successful PVI at 100% and successful LAAC in 151/155 patients (97.4%). The primary safety endpoint was observed in 3/155 patients (1.9%). Transoesophageal echocardiography and/or CCTA 67 ± 26 days after the procedure showed no device embolization and no device-related thrombus, 24/151 (15.9%) patients showed peri-device gaps of <5 mm while gaps of >5 mm have been observed in 3/151 (2.0%). Among 137/155 patients with available arrhythmia, a follow-up >6 months at 78.1% showed sinus rhythm. CONCLUSION:In this large multicentre study, concomitant PFA-based AF ablation and LAA closure proved to be feasible, effective, and safe and overall procedure duration was short.
