Technical implementation of percutaneous thrombus aspiration using the AngioVac system.

OBJECTIVES: The AngioVac system (AngioDynamics, Latham, NY, USA) provides a method for the minimally invasive, percutaneous aspiration of thrombus formations originating from the central venous system as well as solid matter such as lead vegetations and right atrial thrombi. METHODS: This retrospective, observational study describes the initial experience in 52 adult patients with the AngioVac system, focusing mainly on the development of the extracorporeal circuit to improve usability and safety. RESULTS: The mean patient age was 62.9 years (range 23-86 years). 22 patients were female and 30 were male. Indications for percutaneous aspiration were lead vegetations (n = 36; 69.2%), right atrial thrombi (n = 9; 17.3%), central venous thrombi (n = 5; 9.6%) and pulmonary embolisms (n = 2; 3.8%). Successful aspiration was performed in 44 cases (84.6%) and partial success was achieved in five patients (9.6%), while failure to remove thrombi or vegetations occurred in three cases (5.8%). Our practical experience led to the installation of a shunt line for recirculation and the implementation of safety features concerning air handling, which are also employed in minimally invasive extracorporeal bypass circuits. Initial tests monitored the level of negative pressure according to differences in flow and access sites but these still have to be validated on a larger scale. CONCLUSION: In this initial experience, the AngioVac system appeared to be safe regarding the extracorporeal circulation and the elimination of thrombi and lead vegetations.

Simulation-based training of critical events during cardiopulmonary bypass: importance of a critical events checklist.

OBJECTIVES: Evaluation of critical events training for clinical perfusionists is necessary to improve this educational approach. Critical events checklists are effective in reducing clinical complications, but should be tested in a simulation environment first. Individual behavior and stress response of clinical perfusionists during simulated critical events on cardiopulmonary bypass have not been evaluated yet. This study focuses on the evaluation of critical events training and critical events checklists in simulated cardiopulmonary bypass. METHODS: A total of 19 clinical perfusionists from a single hospital took part in two simulated critical event scenarios. Clinical perfusionist behavior and physiological responses were recorded using eye tracking, heart rate variability, video, and audio. In addition, workloads were determined and participants were interviewed. RESULTS: Relevant areas of interest were identified for each simulation phase. During critical event detection and subsequent decision-making, areas of interest hits and fixation durations varied with the use of a critical events checklist. Times to decision were shorter, decision quality was higher, and temporal workload was increased when the checklist was used. Evaluation of selected heart rate variability measures revealed a good correlation with pupil diameters. CONCLUSION: Evaluation of critical events during simulated cardiopulmonary bypass shows that the scenario is realistic and relevant for clinical practice. Integrating a critical events checklist improves the probability of correct decision-making and shortens the correct decision time. Temporal workload is increased when using a checklist. Eye tracking and heart rate variability are well suited to evaluate participants' behaviors and stress levels. All participants welcomed simulation training for critical incidents.

Aortic valve replacement with or without myocardial revascularization in octogenarians. Can minimally invasive extracorporeal circuits improve the outcome?

OBJECTIVE: The positive impact of minimally invasive extracorporeal circuits (MiECC) on patient outcome is expected to be most evident in patients with limited physiologic reserves. Nevertheless, most studies have limited their use to low-risk patients undergoing myocardial revascularization. As such, there is little evidence to their benefit outside this patient population. We, therefore, set out to explore their potential benefit in octogenarians undergoing aortic valve replacement (AVR) with or without concomitant myocardial revascularization. METHODS: Based on the type of the utilized ECC, we performed a retrospective propensity score-matched comparison among all octogenarians (n = 218) who received a primary AVR with or without concomitant coronary artery bypass grafting in our institution between 2003 and 2010. RESULTS: A MiECC was utilized in 32% of the patients. The propensity score matching yielded 52 matched pairs. The 30-day postoperative mortality (2% vs. 10%; p=0.2), the incidence of low cardiac output (0% vs. 6%; p=0.2) and the Intensive Care Unit (ICU) stay (2.5 ± 2.6 vs. 3.8 ± 4.7 days; p=0.06) were all in favour of the MiECC group, but failed to reach statistical significance while the 90-day postoperative mortality did (2% vs. 16%; p=0.02). CONCLUSION: MiECCs have a positive influence on the outcome of octogenarians undergoing AVR with or without concomitant coronary artery bypass grafting. Their use should, therefore, be extended beyond isolated coronary artery bypass graft (CABG) surgery.

Managing large lead vegetations in transvenous lead extractions using a percutaneous aspiration technique.

BACKGROUND: Treatment of patients with systemic infections of cardiac implantable electronic devices and large lead vegetations are a clinical challenge. In such situations patients potentially had to undergo open surgical extraction in the past. The objective of this study was to evaluate the results of a concomitant percutaneous, minimal-invasive aspiration procedure with the use of an extracorporeal circulation in transvenous lead extraction procedures in patients with large lead vegetations. RESEARCH DESIGN AND METHODS: Prior and during transvenous lead extraction procedures lead vegetations were targeted for removal with a percutaneous aspiration technique based on a veno-venous extracorporeal circulation with an in-line filter. Clinical outcomes of the procedures were retrospectively analyzed. RESULTS: This innovative and minimal-invasive treatment concept was used in 35 patients with systemic CIED infections (mean echocardiographic lead vegetation size 22.6 (12-40) mm). Complete procedural success of the aspiration procedure was seen in 88.6% of the patients. No major complication related to the aspiration procedure occurred. Clinical success of the concomitant transvenous lead extraction procedures (35 patients, 83 leads) was 97.1%. CONCLUSION: The presented data show that the aspiration procedure is safe and efficient as an adjunct in transvenous lead extraction procedures avoiding the need for open surgical extraction in such cases.

Impact of minimally invasive extracorporeal circuits on octogenarians undergoing coronary artery bypass grafting. Have we been looking in the wrong direction?

OBJECTIVES: Minimally invasive extracorporeal circuits (MiECCs) aim at the preservation of physiologic reserves, the impact of which is expected to be most evident in patients in whom these are depleted. In this context, octogenarians present a subpopulation of specific interest. METHODS: Based on the type of the utilized ECC, we performed a retrospective comparison between all octogenarians (n = 324) who received a primary coronary artery bypass in our institution from 2003 until 2010. RESULTS: An MiECC was used in 52% of patients. Preoperative variables showed that the MiECC patients were older (83 ± 2 vs 82 ± 2 years; P = 0.001), had higher incidence of renal dysfunction (8% vs 3%; P = 0.04), moderately reduced left ventricular function (43 vs 33%; P = 0.07) and lower incidence of unstable angina (20% vs 28%; P = 0.06). To overcome these differences, a propensity score matching was performed and yielded 126 matched pairs of patients. The overall transfusion of packed red blood cells (2.3 ± 2.3 vs 3.4 ± 3.2 units per patint; P = <0.001), the rate of low cardiac output (0% vs 6%; P = 0.01) and the 30-day postoperative mortality (2.4% vs 9.5%; P = 0.02) were all in favour of the MiECC group in the matched patient population. CONCLUSIONS: The MiECC concept has shown its benefits regarding both morbidity and mortality in this high-risk patient population. We believe that this beneficial effect finds its reason in a better preservation of physiologic reserves that are essential for a positive outcome in this patient group.