Left Atrial Appendage Occlusion Under Miniaturized Transesophageal Echocardiographic Guidance and Conscious Sedation: Multicenter European Experience.

BACKGROUND: Left atrial appendage occlusion (LAAO) procedures are widely guided by standard transesophageal echocardiography (TEE) probes, requiring general anesthesia in most patients. The use of miniaturized TEE probes allows for LAAO guidance under local anesthesia and offers an attractive imaging alternative to standard TEE probes. OBJECTIVES: The aim of this study was to assess the safety and efficacy of miniaturized TEE probes for procedural guidance of LAAO. METHODS: Multicenter retrospective observational study of LAAO procedures performed under miniaturized TEE guidance and conscious sedation. The primary efficacy endpoint was technical success. The secondary efficacy endpoint was procedural success (technical success without major periprocedural complications). The safety outcome was a composite of major periprocedural complications. RESULTS: A total of 546 consecutive LAAO procedures were performed in 5 European centers. Technical success was achieved in 534 (98.0%) patients. Sixteen major periprocedural complications occurred in 15 (2.9%) patients, yielding a procedural success rate of 97.0%. Conversion to general anesthesia was required in 4 (0.7%) patients. Short-term imaging follow-up was available in 422 patients with an incidence of major (>5 mm) TEE-detected residual leaks of 0.7%, complete LAA occlusion of 82.2% on cardiac computed tomography, and device-related thrombus of 5%. As compared with procedural 2-dimensional imaging for device sizing, preprocedural assessment by 3-dimensional imaging resulted in improved technical success (100% vs 95.0%; P < 0.001). CONCLUSIONS: LAAO under conscious sedation and miniaturized TEE guidance is safe and feasible with a high rate of technical success and a low rate of periprocedural complications.

Impact of Device Implant Depth After Left Atrial Appendage Occlusion.

BACKGROUND: Device-related thrombus (DRT) remains one of the main concerns after left atrial appendage occlusion (LAAO). Several risk factors have been proposed, but most cannot be modulated. A modifiable factor such as device implantation depth is a potential target to adjust the risk for DRT. OBJECTIVES: The aim of this study was to assess the impact of LAAO device implantation depth as a predisposing factor for DRT. METHODS: The study included patients who underwent successful LAAO at 9 centers in Europe and Canada. Patients were classified into 2 groups: proximal device implantation (covered pulmonary ridge [PR] in the lobe and disc cohort or <5 mm from the PR in the single-lobe cohort) and distal device implantation (uncovered PR in the disc and lobe cohort and ≥5 mm in the single-lobe cohort). RESULTS: A total of 1,317 patients were included. Among these, proximal and distal device implantation was achieved in 732 (55%) and 585 (45%) patients, respectively. No differences in procedural outcomes were observed between the groups. At follow-up, patients with proximal implantation had a lower incidence of DRT (2.3%) than those with distal implantation (12.2%) (P < 0.001). Deeper device implantation and a larger uncovered left atrial appendage area were associated with a higher incidence of DRT (P < 0.001), regardless of device type. In multivariable analysis, distal implant (HR: 5.92; 95% CI: 3.39-10.36) and no or single antiplatelet therapy (HR: 1.62; 95% CI: 0.99-2.62) emerged as independent predictors of DRT. CONCLUSIONS: LAAO device implantation depth is an independent risk factor for DRT. Deeper device implantation and larger uncovered left atrial appendage areas were associated with a higher incidence of DRT.

Case Report: About a Case of Hyperammonemia Syndrome Following Lung Transplantation: Could Metagenomic Next-Generation Sequencing Improve the Clinical Management?

Background: Mycoplasma hominis and Ureaplasma spp. are responsible for opportunistic infections in transplant patients, sometimes causing a life-threatening hyperammonemia syndrome. Both pathogens are not identified with standard microbiology techniques, resulting in missed or delayed diagnosis. We present a clinical case that illustrates the added value that next-generation sequencing (NGS) may offer in the diagnosis of respiratory infections in immune-compromised patients. Results: A 55 years-old man with idiopathic pulmonary fibrosis underwent double lung transplantation. He received antibiotic prophylaxis with piperacillin-tazobactam and azythromycin. At day 4 post-transplantation (PTx), the patient presented an acute respiratory distress. A broncho-alveolar lavage (BAL) was performed. At day 5 PTx, the patient presented a status epilepticus due to diffuse cerebral oedema. Serum ammonia concentration was 661 µg/dL. BAL bacterial culture was negative. Because of the clinical presentation, special cultures were performed and identified 100.000 CFU/mL of M. hominis and Ureaplasma spp. and specific PCRs were positive for M. hominis and Ureaplasma parvum. Antibiotic therapy was shifted to therapeutic dose of azithromycin and doxycycline; within 48 h ammonia serum concentrations returned to normal but the coma persisted several weeks, followed by a persistent frontal lobe syndrome. A follow-up BAL was performed on day 11 Ptx. The Mycoplasma/Ureaplasma culture was negative, yet the specific PCRs remained positive. Bacterial culture found 100 CFU/mL of Staphylococcus aureus and viral culture was positive for Herpes Simplex Virus-1. These results were confirmed by metagenomic next-generation sequencing (mNGS). In the bacterial fraction, the majority of reads belonged to Corynebacterium propinquum (34.7%), S. aureus (24.1%) and Staphylococcus epidermidis (17.1%). Reads assigned to M. hominis, Ureaplasma urealyticum and parvum represented 0.71, 0.13, and 0.04% of the bacterial fraction and corresponded to 6.9 × 103, 9.7 × 102, and 3.7 × 102 genome equivalents per mL of BAL fluid, respectively. These results are in favor of a cure of the atypical infection. Conclusions: mNGS offered added diagnostic and quantitative values compared to PCR tests, which can remain positive after resolved infections. The initiation of appropriate antibiotic therapy would have occurred earlier on, possibly resulting in a better clinical outcome if mNGS had been performed in a routine fashion.