Pulmonary vein isolation by radiosurgery: implications for non-invasive treatment of atrial fibrillation.

Aims: Electrical isolation of the pulmonary veins (PVs) has been established in clinical routine as a curative treatment for atrial fibrillation (AF). While catheter ablation carries procedural risks, radiosurgery might be able to non-invasively induce lesions at the PV ostia to block veno-atrial electrical conduction. This porcine feasibility and dose escalation study determined the effect of radiosurgery on electrophysiologic properties of the left atrial-PV junction.

Dose-escalation study for cardiac radiosurgery in a porcine model.

Purpose: To perform a proof-of-principle dose-escalation study to radiosurgically induce scarring in cardiac muscle tissue to block veno-atrial electrical connections at the pulmonary vein antrum, similar to catheter ablation.

Methods And Materials: Nine mini-pigs underwent pretreatment magnetic resonance imaging (MRI) evaluation of heart function and electrophysiology assessment by catheter measurements in the right superior pulmonary vein (RSPV). Immediately after examination, radiosurgery with randomized single-fraction doses of 0 and 17.

Propofol in bronchoalveolar lavage during anaesthesia.

Background: The lung protecting effect of propofol requires methods to measure the propofol concentration of the epithelial line fluid covering the alveolar surface. We hypothesized that (1) propofol can be determined in bronchoalveolar lavage (BAL) by reversed phase high performance liquid chromatography with fluorescence detection. (2) Positive end-expiratory pressure (PEEP) ventilation may have an effect on propofol concentration in BAL (cpB).

Time course of ethanol and propofol exhalation after bolus injection using ion molecule reaction-mass spectrometry.

The transit of ethanol from blood to breath gas is well characterised. It is used for intraoperative monitoring and in forensic investigations. A further substance, which can be measured in breath gas, is the phenol propofol.

Impact of valves in a biomechanical heart model assisting failing hearts.

Experimental valveless muscular blood pumps (biomechanical hearts) in goats can pump more than 1 L.min(-1), but due to a high pendulum volume, no significant flow contribution to the circulation is gained. Thus valved and valveless biomechanical hearts were compared for efficacy.

Bio-technologies for a glandular stem cell cardiomyopexy.

The glandular stem cell cardiomyopexy should become a treatment option for end-stage heart failure. It combines an expected regenerative potential of transformed adult glandular stem cells into cardiomyocytes within the myocardium or onto the myocardium of the recipient and the potential of a hypercapillarized latissimus dorsi muscle (LDM) wrapped around the heart for stem cell nutrition and girdling.

Assessment of regional lung recruitment and derecruitment during a PEEP trial based on electrical impedance tomography.

Objective: To investigate whether electrical impedance tomography (EIT) is capable of monitoring regional lung recruitment and lung collapse during a positive end-expiratory pressure (PEEP) trial.

Design: Experimental animal study of acute lung injury.

Subject: Six pigs with saline-lavage-induced acute lung injury.

Changes in corneal hysteresis after clear corneal cataract surgery.

Purpose: To assess the changes in corneal hysteresis (CH) as measured by the Ocular Response Analyzer (ORA; Reichert Ophthalmic Instruments, Buffalo, New York, USA) to describe the influence of clear corneal cataract surgery on corneal viscoelastic properties and intraocular pressure (IOP) measured by noncontact tonometry (NCT) and Goldmann applanation tonometry (GAT).

Design: Retrospective, interventional, comparative study.

Methods: One hundred and one eyes of 101 consecutive patients who underwent routine clear corneal cataract surgery were evaluated.

Differences of propofol concentrations in mammalian whole blood and in corresponding plasma samples analyzed by high performance liquid chromatography.

Background: In preparation for a study of the pharmacokinetics and elimination of propofol, a frequently used intravenous narcotic, we sought for a simple but accurate method for determining the drug in biological fluids from various mammalian species.

Materials And Methods: We established an isocratic high performance liquid chromatography (HPLC) assay with fluorimetric detection for quantification of propofol, studied the analytical characteristics of the method, and measured the narcotic in heparinized whole blood and corresponding plasma samples drawn from 5 subjects each of humans, pigs, sheep and goats prior to and after 10 minutes of constant infusion of propofol.

Results: Following protein precipitation with methanol, propofol was quantified in the alcoholic phase.

Discontinuous monitoring of propofol concentrations in expired alveolar gas and in arterial and venous plasma during artificial ventilation.

Background: Analyzing propofol concentration in expired alveolar gas (cPA) may be considered as a convenient, noninvasive method to follow the propofol concentration in plasma (cPPL). In the current study, the authors established procedures to measure cPA and cPPL for the assessment of their relation in two animal models during anesthesia.

Methods: Expired alveolar gas and mixed venous and arterial blood were simultaneously sampled during continuous application of propofol for general anesthesia to three goats and three pigs.

Strategies for the reduction of cerebral microembolism during transmyocardial laser revascularization.

Background And Objectives: During transmyocardial laser revascularization (TMLR), multiple microembolic signals (MES) can be detected in cerebral arteries. We sought to characterize composition and clinical relevance of these MES and to evaluate strategies to reduce cerebral microembolization during TMLR.

Study Design/materials And Methods: TMLR was performed in pigs.

Development of muscular blood pumps performed in a one-step operation.

Up to now, the employment of skeletal muscle ventricles (SMVs) has required a two-step operation, that is, first, the construction followed by a vascular delay and electrical conditioning, and second, the integration into circulation by a second operation. As shown previously, clenbuterol increased the power of electrically conditioned SMVs wrapped around a mock system. These clenbuterol-supported SMVs pumped successfully from construction to several months against a pressure of 60-70 mm Hg.