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AbstractPurpose: To obtain morphologic and functional information in patients with dissection of the descending aorta using contrast-enhanced MR angiography (MRA) and MR blood flow quantification of the true and false lumina. Material and Methods: Fourteen patients were studied prospectively using a 1.5 T unit. MRA was performed with a 3D FISP sequence (TR/TE/flip angle 4.7/1.9 ms/30°) after injection of 0.2 mmol Gd-DTPA per kg b.w. Flow quantification with phase velocity mapping was done at the level of the diaphragm using a 2D FLASH technique (TR/TE/flip angle 28/6.5 ms/30°) with an average temporal resolution of 23 frames per cardiac cycle (34 ms). A spectral broadening index was applied to quantify the amount of flow irregularity within both channels of the aorta. Extension of the dissection and involvement of the major branch vessels were analyzed. Results: The mean flow volume per minute was 1982 ml (SD 1083 ml) in the true and 1052 ml (SD 763 ml) in the false lumen. Average peak-velocities were 98 cm/s (SD 33 cm/s) in the true channel and 47 cm/s (SD 26 cm/s) in the false channel. Ten patients had bidirectional flow in the false lumen with a reflux volume ranging between 6.8% and 98%. Only 1 patient presented with bidirectional flow in the true lumen (reflux volume 15%). A significantly higher degree of flow irregularity was found in the false lumen compared with the true channel. Conclusion: Different hemodynamic patterns were found in aortic dissection. Their prognostic value and the impact on therapy, specifically percutaneous interventional procedures, have to be further studied. [ABSTRACT FROM AUTHOR]

Extended lesions of the lung parenchyma are often seen in association with blunt chest trauma. Blood aspiration, atelectasis and the formation of bronchopleural fistulae can lead to early respiratory deterioration and the development of severe post-traumatic complications (pneumonia, acute respiratory distress syndrome). Diagnostic and therapeutic bronchoscopy is essential on admission. This procedure helps to estimate the severity and extent of parenchymal lesions even before chest X-ray signs are noted. Bronchoalveolar lavage is needed for removal of aspirates. In our study bronchoalveolar lavage on admission reduced bacterial contamination and pneumonia in comparison to patients not lavaged. A new method for closure of bronchopleural fistulae is described. Fibrin instillation after balloon catheter occlusion leads to a significant reduction of tidal volume loss (greater than 50% in average). [ABSTRACT FROM AUTHOR]

Background: Cardiac allograft rejection and vasculopathy are the main factors limiting long-term survival after heart transplantation.In this pilot study we investigated whether non-invasive methods are beneficial to detect cardiac allograft rejection (Grade 03 R) and cardiac allograft vasculopathy. Thus we compared multi-slice computed tomography and magnetic resonance imaging with invasive methods like coronary angiography and left endomyocardial biopsy.Methods: 10 asymptomatic long-term survivors after heart transplantation (8 male, 2 female, mean age 52.1 +/- 12 years, 73 +/- 11 months after transplantation) were included. In a blinded fashion, coronary angiography and multi-slice computed tomography and ventricular endomyocardial biopsy and magnetic resonance imaging were compared against each other.Results: Cardiac allograft vasculopathy and atherosclerosis were correctly detected by multi-slice computed tomography and coronary angiography with positive correlation (r = 1). Late contrast enchancement found by magnetic resonance imaging correlated positively (r = 0.92, r2 = 0.85, p < 0.05) with the histological diagnosis of transplant rejection revealed by myocardial biopsy. None of the examined endomyocardial specimen revealed cardiac allograft rejection greater than Grade 1 R.Conclusion: A combined non-invasive approach using multi-slice computed tomography and magnetic resonance imaging may help to assess cardiac allograft vasculopathy and cardiac allograft rejection after heart transplantation before applying more invasive methods. [ABSTRACT FROM AUTHOR]

BACKGROUND: Cerebral protection during surgery for acute aortic dissection type A relies on hypothermic circulatory arrest, either alone or in conjunction with cerebral perfusion. METHODS AND RESULTS: The perioperative and intraoperative conditions of 1558 patients submitted from 44 cardiac surgery centers in German-speaking countries were analyzed. Among patients with acute aortic dissection type A, 355 (22.8%) underwent surgery with hypothermic circulatory arrest alone. In 1115 patients (71.6%), cerebral perfusion was used: Unilateral antegrade cerebral perfusion (ACP) in 628 (40.3%), bilateral ACP in 453 (29.1%), and retrograde perfusion in 34 patients (2.2%). For 88 patients with acute aortic dissection type A (5.6%), no circulatory arrest and arch intervention were reported (cardiopulmonary bypass-only group). End points of the study were 30-day mortality (15.9% overall) and mortality-corrected permanent neurological dysfunction (10.5% overall). The respective values for the cardiopulmonary bypass-only group were 11.4% and 9.1%. Hypothermic circulatory arrest alone resulted in a 30-day mortality rate of 19.4% and a mortality-corrected permanent neurological dysfunction rate of 11.5%, whereas the rates were 13.9% and 10.0%, respectively, for unilateral ACP and 15.9% and 11.0%, respectively, for bilateral ACP. In contrast with the ACP groups, there was a profound increase in mortality when systemic circulatory arrest times exceeded 30 minutes in the hypothermic circulatory arrest group (P<0.001). Mortality-corrected permanent neurological dysfunction correlated significantly with perfusion pressure in the ACP groups. CONCLUSIONS: This study reflects current surgical practice for acute aortic dissection type A in Central Europe. For arrest times less than 30 minutes, hypothermic circulatory arrest and ACP lead to similar results. For longer arrest periods, ACP with sufficient pressure is advisable. Outcomes with unilateral and bilateral ACP were equivalent. [ABSTRACT FROM AUTHOR]

Objective: Protection of the myocardium against ischemia/reperfusion injury is a major challenge in cardiac surgery and cardiology. A cardioprotective role of heat shock proteins (Hsp), in particular Hsp 70, against ischemia has been demonstrated. A prerequisite for clinical exploitation of high Hsp 70 levels in the heart during ischemia is the determination of the efficacy and the kinetics of cardiac Hsp synthesis in vivo. Methods: We examined Hsp 70 and other immediate early genes, that are induced by cardioplegia and reperfusion, in right atrial biopsies taken from 15 patients during coronary artery bypass grafting. Specimens were obtained before cardioplegia and after ending of reperfusion and subsequently studied by immunohistochemistry and Western blot analyses. Results: Overall Hsp 70 increased 2.0±1.1-fold (P<0.01) in the nucleus as well as in the cytosol of myocytes and endothelial cells during open-heart surgery. As determined by comparison to a dilution series of recombinant protein, Hsp 70 levels amounted up to 6‰ of total cellular protein. The increase of Hsp 70 correlated well with the duration of cardioplegia and reperfusion (P<0.005) showing a markedly accelerated increase at periods longer than 2 h. Further, the immediate early gene c-Fos also increased 2.4±2.2-fold during open-heart surgery (P<0.05), whereas other members of the Hsp family, like Hsp 27 and Hsp 90, showed no significant changes in protein levels during cardioplegia and reperfusion. Conclusions: These findings demonstrate that protein levels of Hsp 70 in the myocardium increase to significant amounts within few hours after induction. The optimum time point for induction of Hsp 70 appears to be at least 2 h before open-heart surgery. [Copyright &y& Elsevier]

An abstract of the medical research "On the pathology of malignant pulmonary tumors after percutaneous radiofrequency ablation," byu S. Kröber, S. Clasen, A. Böhmches, P. Pereira, H. Aebert and B. Bültmann is presented.