Giant Aneurysm of the Right Coronary Artery: Multimodality Imaging and Interventional Management.

A large (40-mm) circular structure in the right atrioventricular groove was detected by transthoracic echocardiography and was diagnosed as a giant aneurysm of the right coronary artery. Through invasive mapping by a guide extension catheter, the aneurysm could be excluded by implantation of 3 overlapping stent grafts. (Level of Difficulty: Beginner.).

Culture of Spirogyra sp. in a flat-panel airlift photobioreactor.

Spirogyra is a green filamentous freshwater algae on which recent studies reveal several promising properties and potential application possibilities in biotechnology. However, little is known about cultivation of Spirogyra and even less about large-scale cultivations in closed growth systems. Therefore, the aim of the present study was to elaborate the growth kinetics of Spirogyra sp. in a commercially available and scalable photobioreactor. For this purpose, Spirogyra sp. was grown indoors in distinct flat-panel airlift photobioreactors equipped with culture-flow directing installations. Hereby, special attention was laid on light administration and specific light availability and it was found that Spirogyra sp., in combination with the photobioreactor in question, required high photon-flux densities (100 µmol m-2 s-1 gDW-1) for maximum proliferation which is in accordance with its abundance in epipelagial waters in nature. Applying photon-flux densities of up to 1400 µmol m-2 s-1, a maximum volumetric productivity and final biomass concentration of 1.15 gDW L-1 day-1 and 14.28 gDW L-1 were achieved, respectively, the highest to be reported for the alga. To the knowledge of the authors, this is the first report on the growth of Spirogyra in a flat-panel photobioreactor.

ECMO and cytokine removal for bridging to surgery in a patient with ischemic ventricular septal defect - a case report.

Even in the modern era of percutaneous coronary intervention, postinfarction ventricular septal defect (VSD) remains a serious and often lethal complication. Whether or not immediate surgical repair or delaying surgery a few days aided by intra-aortic counterpulsation provides the optimal strategy remains a matter of debate. An interdisciplinary approach of intensivists and cardiac surgeons in this setting is mandatory. We report the use of veno-arterial extracorporeal membrane oxygenation and extracorporeal blood purification therapy (CytoSorb®) as bridging to surgical closure in a patient with an ischemic VSD leading to protracted cardiogenic shock after posterior myocardial infarction.

Growth of Cyanobacterium aponinum influenced by increasing salt concentrations and temperature.

The increasing requirement of food neutral biofuels demands the detection of alternative sources. The use of non-arable land and waste water streams is widely discussed in this regard. A Cyanobacterium was isolated on the area of a possible algae production side near a water treatment plant in the arid desert region al-Wusta. It was identified as Cyanobacterium aponinum PB1 and is a possible lipid source. To determine its suitability of a production process using this organism, a set of laboratory experiments were performed. Its growth behavior was examined in regard to high temperatures and increasing NaCl concentrations. A productivity of 0.1 g L-1 per day was measured at an alga density below 0.75 g L-1. C. aponinum PB1 showed no sign of altered growth behavior in media containing 70 g L-1 NaCl or less. Detection of a negative effect of NaCl on the growth using Pulse-Amplitude-Modulation chlorophyll fluorescence analysis was not more sensitive than optical density measurement.

Forty-one-month follow-up of the Symmetry aortic connector system for proximal venous anastomosis.

OBJECTIVE: Results of short- and midterm follow-up studies of the patency rate of the Symmetry aortic connector systems (St Jude Medical, Inc, Minneapolis, Minn) are controversial. Long-term follow-up studies are still lacking (so far, the longest mean follow-up period was 19 months). The aim of our study was (1) to evaluate the patency rate of this device over a longer time-period and (2) to analyze risk factors for graft occlusion. METHODS: Between November 2000 and July 2003, 76 Symmetry aortic connector systems were implanted in 42 patients. At follow-up, 24 patients with 44 mechanical connectors were studied with 64-slice cardiac computed tomography. Eight patients had died previously, 6 patients refused to undergo a computed tomographic scan, and 4 patients had to be excluded because of impaired renal function. RESULTS: From a total of 44 mechanical connectors studied, 24 (55%) were occluded, 20 (45%; confidence intervals 31%-61%) were patent, and 7 of these grafts showed stenosis in the area of the connector. Mean follow-up was 41 +/- 10 months (18-52 months). Sex, age, left main stenosis, hyperlipidemia, hypertension, renal failure, target vessel, stenosis of the target vessel, diameter of the target vessel, type of surgical intervention, diabetes, ejection fraction, postoperative anticoagulation regimen, and the connector size showed no significant influence on the bypass graft patency (P > .05). The bypass graft flow was recognized to be the only risk factor for bypass graft occlusion (P = .0256). CONCLUSION: Midterm follow-up data show a high number of occluded Symmetry aortic connector system vein grafts. On the basis of these observations, the use of the connector was abandoned at our institution.

Influence of a tilting prosthetic mitral valve orientation on the left ventricular flow - an experimental in vivo magnetic resonance imaging study.

OBJECTIVE: Orientation-related monoleaflet mechanical valve flow and velocity studies in the downstream are limited in mitral valve replacement studies. METHODS: In five sheep, ventricular blood flow was visualized prior to the implantation of a Medtronic Hall tilting valve model. In six sheep, the implant orientation was either anatomical (disc aligned with the anterior leaflet) or anti-anatomical. The mitral subvalvular apparatus was preserved. Sheep were positioned within an 1.5 T field strength MR scanner (Magnetom Sonata; Siemens) to assess time-dependent three dimensional blood flow. RESULTS: The preoperative ventricular velocity profiles presented negligible individual variances. Streamlines passed homogeneously without any spatial differences in flow velocities into the left ventricle. Starting from the anatomical position, blood entered mainly through the major orifice of the mechanical valve. The single artificial leaflet mimicked the rudder effect of the natural anterior mitral leaflet, preventing blood streaming directly towards the septum. The area with inhomogeneous blood velocities in the ventricle increased but not significantly from the preoperative status. The non-axial inflow not directed directly to the apex converted to a similar helix as observed in the preoperative cases. Anti-anatomical orientation of the prosthesis caused a significant increase in turbulence immediately after passing the mitral prosthesis. The main stream was changed so significantly that the blood flow shifted towards the septum and caused higher velocities of the stream profiles and turbulence apically. CONCLUSIONS: To achieve optimal hemodynamics, orientation of the mitral tilting valve has to be considered carefully, as has been long known from aortic valve replacement studies.

Superior left atrial approach to the mitral valve: incidence of postoperative arrhythmia.

BACKGROUND AND AIM OF THE STUDY: The superior left atrial approach to mitral surgery involves exposure of the mitral valve through a longitudinal, craniocaudally orientated incision in the roof of the left atrium. The study aim was to evaluate the incidence of postoperative arrhythmias following this procedure. METHODS: Fifty-nine patients underwent either mitral valve repair (n = 20), mitral valve replacement (n = 26) or an associated procedure (n = 13), including aortic valve replacement, coronary artery bypass grafting and atrial septal defect closure. Eight patients had undergone previous surgery on the mitral valve. Patients were classified according to their preoperative rhythm: sinus rhythm (SR), paroxysmal or chronic atrial fibrillation (AF), or permanent pacing. Changes in cardiac rhythm were evaluated postoperatively, after four weeks, and at late follow up (mean 23.8 months). RESULTS: Preoperatively, 24 patients had shown SR, 10 had paroxysmal AF, 24 had chronic AF, and one patient had permanent pacing. At the time of discharge, SR was recorded in 18 patients who had SR preoperatively, in seven who had paroxysmal AF preoperatively, and in one patient who had chronic AF preoperatively. At follow up, SR was seen in 19 patients with preoperative SR, in seven with paroxysmal AF preoperatively, and in two with chronic AF preoperatively. Four patients received permanent pacemakers postoperatively due to total heart block or bradycardia. CONCLUSION: The superior left atrial approach to mitral valve surgery appears to be safe as it maintains the sinus rhythm in a high proportion of patients postoperatively. In addition, it is not normally prone to technical complications.

Dissociation of slow waves and fast oscillations above 200 Hz during GABA application in rat somatosensory cortex.

Fast electrical oscillations (FOs; > 200 Hz), superimposed on vibrissa-evoked slow potentials, may support rapid sensory integration in neocortex. Yet, while it is well established that the positive/negative (P1/N1) slow wave of the somatosensory evoked potential primarily reflects sequential activation of supragranular and infragranular pyramidal cells mediated chiefly via excitatory chemical synaptic pathways, little is known about the generation of FOs. In this study, laminar current source-density analysis and principal component analysis indicated that FOs are generated by two dipolar current sources situated in the supra- and infragranular layers, similar in laminar location to the two current dipoles associated with the slow wave. However, exogenous GABA application reversibly abolished the N1 slow wave, leaving the P1 intact, while the FO was unaffected by GABA. Furthermore, reductions in both supra- and infragranular cortical unit discharge during application of GABA suggests that FO generation is not dependent on the same intracortical synaptic circuits that are associated with the N1 slow wave. These data suggest a marked functional dissociation between neural mechanisms underlying the slow and fast components of the vibrissa-evoked response.

MR imaging-based port placement planning for totally endoscopic coronary artery bypass grafting.

An easy applicable method for pre-operative port position planning for totally endoscopic coronary artery bypass (TECAB) grafting based on magnetic resonance (MR) coronary angiography and image post-processing is introduced and analyzed. For this, combined left main (LM) and left anterior descending (LAD) coronary arteries of 21 subjects (14 patients, 7 healthy volunteers with similar habitus) were investigated in MR by means of transversally orientated, three-dimensional (3D), fat-saturated, breath-hold true fast imaging with steady state precession sequences with real-time navigator-based slice following. For the healthy volunteers, the vertical dimension of the total 3D slab was enlarged to enable TECAB planning. Optimal endoscopic port positions were determined via image analysis and geometric methods. 13.8+/-2.1 cm mean continuously visible length of combined LM and LAD coronary arteries (no statistical difference between patients and healthy volunteers) allowed visualizing typical regions for suturing of the anastomosis in all 21 cases. The mean horizontal distance of the optimal endoscopic port position from the center of the sternum was 7.0+/-1.3 cm. In conclusion, MR imaging-based port position planning is feasible. Variability in the determined port positions indicates the necessity of adaptation of port positioning even for subjects with similar habitus.