'Just the two of us': single-operator interventional left atrial appendage closure-a case report.

Background: Different procedural strategies have been published targeting to facilitate transcatheter left atrial appendage closure (LAAc). We demonstrate feasibility of a procedural set-up allowing single-operator LAAc in a selected patient. Case summary: A 87-year-old male with persistent Afib (CHA2DS2VASc, five; HASBLED, three) was referred to our hospital for LAAc. Pre-procedural planning and device sizing with three-dimensional transesophageal echocardiography (3DTEE) confirmed a non-complex anatomy of the essential anatomical structures predicting suitability for LAAc. Therefore, the procedure was performed with a simplified single-operator interventional approach. Intraprocedural TEE guidance, device preparation, and LAAc were accomplished by the interventionalist himself. For procedural guidance, the TEE probe was arranged and handled in a technique comparable to the use of intracardiac echocardiography (ICE). Procedure time (skin-to-skin) was 21 min, left atrial access time 9 min, and fluoroscopy time was 4:28 min without the use of contrast dye. The patient was discharged the following day in good medical conditions. Discussion: To the best of our knowledge, this is the first report on successful single-operator LAAc in a selected patient. The intervention, pre-procedural screening, and intraprocedural 3D TEE were performed by one single experienced interventionalist. This simplified technique is based on a standardized pre-procedural imaging-protocol with 3D echocardiography. According to our experience, this streamlined approach is a valuable option in non-complex LAAc cases. In the growing field of structural cardiac interventions, this approach might be an interesting option for centres with limited personal and technical resources.

A comparison of two-dimensional and real-time 3D transoesophageal echocardiography and angiography for assessing the left atrial appendage anatomy for sizing a left atrial appendage occlusion system: impact of volume loading.

AIMS: Correct sizing of a left atrial appendage (LAA) closure system is important to avoid redeployment of the device and peri-device leaks. The aims of this study were to assess the significance of two-dimensional transoesophageal echocardiography (2D-TEE), real-time 3D transoesophageal echocardiography (RT 3D-TEE) and angiography for measuring the size of the LAA landing zone and to determine the impact on sizing an LAA closure device. Furthermore, we investigated the relevance of volume loading on LAA size. METHODS AND RESULTS: In a prospective study, 46 patients underwent 2D-TEE and RT 3D-TEE 24 hours prior to LAA closure, at the beginning of the procedure and just before the procedure after volume loading with an average of 1,035±246 ml. Angiography was performed immediately before the implantation. Maximal diameter (2.2±0.4 versus 2.3±0.4 cm; p<0.01), perimeter (6.5±1.0 versus 6.8±1.0 cm, p<0.01) and area (3.2±1.0 versus 3.5±1.1 cm², p<0.01) of the LAA increased significantly after volume loading. The highest correlation (R) between measurements and LAA device size was found for RT 3D-TEE-derived perimeter (R=0.97) and area (R=0.96), whereas the maximal diameter (R=0.78) measured by 2D-TEE and angiography (R=0.76) correlated less closely. Sizing based on an RT 3D-TEE-measured perimeter resulted only in 4% of undersizing the implanted device. Peri-device leaks occurred in seven cases (15%) and were associated with a lower compression of LAA devices (7±1.3% versus 14±3.2% for patients without leaks, p<0.001). CONCLUSIONS: Volume loading before LAA closure increases LAA dimensions significantly. RT 3D-TEE measurements show a closer correlation to LAA closure device size than 2D-TEE or angiographic measurements.

Excessive methaemoglobinaemia and multi-organ failure following 4-DMAP antidote therapy.

This report describes the clinical history of a patient intoxicated with methyl isocyanate (MIC), a toxic agent first receiving attention in 1984 after a mass accident in a pesticide plant in Bhopal, India, and treated with the cyanide-specific antidote 4-DMAP. The numerous clinical conditions requiring 39-day intensive care treatment included ARDS, renal and hepatic failure, haemolysis, bone marrow depression, septic encephalopathy and critical illness polyneuropathy. The most outstanding condition, however, was a methaemoglobinemia of 86.7%, which was predominantly related to the use of 4-DMAP, although uptake of MIC may have been a significant contributing factor. Since significant cyanide intoxication could be excluded clinically and by laboratory testing in the initial phase of emergency treatment, most of the clinical effects were due to the side-effects of the antidote therapy. Due to intensive therapy, the patient survived without any neurological or organ deficit. This case shows that antidotes should be used cautiously in cases where uncertainties about the nature of the underlying toxic agent exist. This may prevent severe side-effects associated with antidote therapy, e.g. 4-DMAP, if there is-as in our case-a mismatch between the toxic agent and the antidote.