[Requirements for outpatient care after implantation of a ventricular assist device : Views of patients and their relatives]. / Anforderungen an die ambulante Versorgung nach Implantation eines ventrikulären Herzunterstützungssystems : Sichtweise von Patienten und Angehörigen.

Ventricular assist device (VAD) implantation has developed into a well-established option when conservative treatment of terminal heart failure has been exhausted. Figures from 2015 make this clear: only 283 heart transplantations were performed nationwide but 959 VAD systems were implanted. It is noteworthy that the survival times with a VAD are approaching the survival times after heart transplantation. Patients with VADs have a life-long dependency on their proximity to specialists. So far, the requirements for outpatient care have not been systematically recorded from the perspective of VAD patients and their relatives. In September 2016, VAD patients (n = 30) and their relatives (n = 25) were anonymously questioned about their views on postoperative outpatient care. For this purpose, the VAD Patient Satisfaction Survey was adapted to the needs of this study. Patients with VADs and their relatives were found to experience their daily life with a VAD in a positive manner. Information, training, accessibility and regular contacts with the implantation clinic and the VAD coordinator are important pillars of outpatient care after VAD implantation. Almost 95% of surveyed patients regarded good home support as an important factor that makes life with a VAD easier. These aspects should be taken into account in the care of patients living with a VAD.

[Sense of Coherence Scale according to Antonovsky as a possible predictor for return to work for cardiac surgery intensive care patients]. / "Sense-of-coherence"-Skala nach Antonovsky als möglicher Prädiktor für den Wiedereinstieg in das Berufsleben für herzchirurgische Intensivpatienten.

BACKGROUND: For cardiac surgery patients who were employed prior to surgery, the return to their professional life is of special importance. In addition to medical reasons, such as pre-existing conditions, the success of the operation or postoperative course and patient-intrinsic reasons, which can be assessed with the Sense of Coherence (SOC) scale by Antonovsky, may also play a role in the question of a possible return into working life. METHODS: In this study 278 patients (invasive coronary artery bypass graft surgery and/or surgery on heart valves, age < 60 years, employed) were questioned postoperatively via post with the SOC questionnaire. The SOC questionnaire was used in addition to questions about return to work. The cohort was stratified according to the time of return to work. Subsequently, the point of maximum sensitivity and specificity was determined for the total SOC score and the prediction power was considered. RESULTS: Of the 278 patients, 61 questionnaires (22%) were considered as eligible and included in the analysis. Of these, 47 participants had returned to work after undergoing cardiac surgery and 14 participants had not. We observed significant differences in SOC values between both groups (146.07 ± 29.76 versus 124.29 ± 28.8, p = 0.020). Patients that returned to work within the first 6 months after surgery showed even higher SOC scores (148.56 ± 28.98, p = 0.034). CONCLUSION: Patients with an SOC score < 130 are at greater risk not to return to their professional life after cardiac surgery. The SOC is an easily obtainable score that reliably predicts the probability of return to work after cardiac surgery.

A core outcome set for all types of cardiac surgery effectiveness trials: a study protocol for an international eDelphi survey to achieve consensus on what to measure and the subsequent selection of measurement instruments.

BACKGROUND: Cardiovascular disease (CVD) is a major contributor to the burden of disease and the number one cause of death worldwide. From 1990 until today, more people died from coronary heart disease than from any other cause. CVD is regularly treated with minimally or non-minimally invasive off- or on-pump cardiothoracic surgery and several interventions related to the outcome of the surgical procedures have been evaluated in clinical trials, but heterogeneity in outcome reporting hinders comparison of interventions across trials and limits the ability of research synthesis. This problem is encountered with the introduction of core outcome sets (COSs), which should be measured and reported, as a minimum, in all clinical trials for a specific clinical field. METHODS/DESIGN: This study protocol describes the methods used to develop a COS for all types of cardiac surgery effectiveness trials. We aim to reach consensus on what to measure in an international three-round eDelphi exercise involving adult patients in need or after cardiothoracic surgery, cardiothoracic surgeons, cardiologists, anaesthesiologists, nursing staff and researchers with expertise in this particular field of medical research. Subsequently, outcome measurement instruments (how to measure) will be determined. Recommendations on COS development given by the Core Outcome Measures in Effectiveness Trials (COMET) Initiative and the Outcome Measures in Rheumatology (OMERACT) Initiative were followed. DISCUSSION: The proposed COS aims to provide methodological guidance for future cardiothoracic surgical trials to ensure the comparability of effects of interventions across studies and enable research synthesis. This does not imply that primary outcomes should always and exclusively be those of the COS. However, to ensure the comparability of results across trials, the outcomes included in this COS should be considered for inclusion besides measuring trial-specific clinical endpoints.

A novel application for assessing diaphragmatic function by ultrasonic deformation analysis in noninvasively ventilated healthy young adults.

PURPOSE: Noninvasive pressure support ventilation is intended to relieve the load on respiratory muscles and to prevent exhaustion. This includes continuous positive airway pressure (CPAP) as well as pressure support ventilation (PSV). Speckle tracking echocardiography (STE) allows quantification of tissue deformation by tracing characteristic grayscale patterns, independent of the acquisition angle. The aim of the present study was to assess the applicability of using STE as a way to investigate diaphragm movement using deformation analysis as a parameter for respiratory workload. MATERIALS AND METHODS: Healthy male subjects (n = 13, 27 ±â€Š7 years) were treated while in a seated supine position with the following respirator settings: regular breathing, 5 mbar CPAP, CPAP + 5 / + 10 / + 15 mbar PSV. A 2 - 4 MhZ M5S phased array sector transducer was used on a Vivid E 9 (GE, Horton, Norway) to visualize the diaphragm. The inspiratory peak transverse strain was measured as a parameter of maximal inspiratory muscle workload and compared to the M-mode-based fractional thickening (FT). RESULTS: Both the FT and the transverse strain increased significantly under CPAP and PSV. The transverse strain correlated well with the FT (r = 0.753; p < 0.001). CONCLUSION: The results measured by STE were comparable to the M-mode-based measurements. The capturing of a larger diaphragmatic sample area and movement tracking possibly lead to higher precision compared to one-dimensional M-mode. The use of STE in patients might provide a reproducible, bedside method to analyze the respiratory workload. Due to the larger sampling area, it might prove superior to mere M-mode acquisition.

Feasibility and safety of xenon compared with sevoflurane anaesthesia in coronary surgical patients: a randomized controlled pilot study.

BACKGROUND: To date, only limited data exist about the use of xenon as an anaesthetic agent in patients undergoing cardiac surgery. The favourable cardio- and neuroprotective properties of xenon might attenuate postoperative complications, improve outcome, and reduce the incidence of delirium. Thus, the aims of this study were to investigate the feasibility and safety of balanced xenon anaesthesia in patients undergoing cardiac surgery and to gather pilot data for a future randomized multicentre study. METHODS: Thirty patients undergoing elective coronary artery bypass grafting were enrolled in this randomized, single-blind controlled trial. They were randomized to receive balanced general anaesthesia with either xenon (45-50 vol%) or sevoflurane (1-1.4 vol%). The primary outcome was the occurrence of adverse events (AEs). Secondary outcome parameters were feasibility criteria (bispectral index, perioperative haemodynamic, and respiratory profile) and safety parameters (dosage of study treatments, renal function, intraoperative blood loss, need for inotropic support, regional cerebral tissue oxygenation). Furthermore, at predefined time points, systemic and pulmonary haemodynamics were assessed by the use of a pulmonary artery catheter. RESULTS: There were no patient characteristic differences between the groups. Patients undergoing xenon anaesthesia did not differ with respect to the incidence of AE (6 vs 8, P=0.464) compared with the sevoflurane group. No differences were detected regarding secondary feasibility and safety criteria. The haemodynamic and respiratory profile was comparable between the treatment groups. CONCLUSIONS: Balanced xenon anaesthesia is feasible and safe compared with sevoflurane anaesthesia in patients undergoing coronary artery bypass surgery. Acronym CARDIAX: A pre- and post-coronary artery bypass graft implantation disposed application of xenon. Clinical trial registration ClinicalTrials.gov: NCT01285271; EudraCT-number: 2010-023942-63. Approved by the ethics committee 'Ethik-Kommission an der Medizinischen Fakultät der Rheinisch-Westfälischen Technischen Hochschule Aachen (RWTH Aachen)': EK-218/10.

Influence of aortic dimensions on the hemodynamic performance of small aortic valve prostheses: impact on patient/prosthesis mismatch.

BACKGROUND: Since Doppler echocardiography takes no account of pressure recovery, the true hemodynamic burden of aortic valve prostheses remains vague. The purpose of this study was to elucidate the methodological error of Doppler gradient estimation by means of a model demonstrating the different influence of aortic root diameters on net and Doppler gradients, respectively. This matters especially in small valves and the related patient/prosthesis mismatch calculation. METHODS: Two bileaflet small aortic valve prostheses (19 mm SJM Regent® and On-X® valve) were tested using a pulsatile circulatory mock loop simulator with two different aortic models: one with statistically normal diameters according to annular size, another one simulating an aortic aneurysm of 50 mm. Doppler and simultaneously recorded net gradients as well as systolic energy losses were obtained for different hemodynamic conditions. RESULTS: In all measurements a significant amount of pressure recovery was observed. In cases of aortic aneurysm systolic energy loss increased significantly for each cardiac output at each heart rate ( P < 0.0028), reflected by a significant ( P < 0.0001) increase in net gradients. The corresponding Doppler gradients were unchanged. This indicates significantly less pressure recovery ( P < 0.0001) in the aneurysmatic aorta. CONCLUSIONS: Geometry of the ascending aorta considerably alters aortic valve hemodynamic parameters. The hemodynamic function of small aortic valve prostheses, especially with corresponding normal outflow dimensions, is much better than expected from Doppler gradients. Thus, calculation of a patient/prosthesis mismatch can be misleading.

A four-muscle-flap for thoracomyoplasty in patients with sacrificed thoracodorsal vessels.

UNLABELLED: Defects after prior posterolateral thoracotomy and with concomitant bronchiopleural fistula remain a challenge for the plastic surgeon. In most of the cases, the thoracodorsal artery division after posterolateral thoracotomy impairs the vascularisation supply of the latissimus dorsi, resulting in the loss of this option for closure of the pleural cavity. Therefore, the adequate filling of residual empyema space and/or surgical closure of the bronchial stump insufficiency needs additional tissue to overcome this situation. We present an alternative approach using a four-muscle-flap technique including the infraspinatus, the subscapularis and the teres major and minor muscle group, all pedicled from the subscapular artery as a part of a modified thoracomyoplasty technique for closing the residual empyema space and bronchial stump insufficiency. METHODS: Between 2002 and 2008, we performed the four-muscle-flap on seven patients (mean age 68±7.9 years) with residual empyema space. Three cases were combined with a bronchopleural fistula. All patients received a two-stage procedure. First, the thoracic surgeons performed an open-window thoracostomy. This procedure was followed by the definitive surgical treatment after 3-6 months. In cases with an additional bronchial insufficiency, the stump was covered in with a subscapularis muscle. The infraspinatus and the teres muscle group were used to fill the pleural cavity, in combination with the thoracoplasty. RESULTS: In this series, no mortality connected to the procedure was noted. The mean postoperative stay in the intensive care unit (ICU) was 3±2.9 days and the patients were discharged from the hospital after 15±7.6 days. Minor postoperative complications occurred in two cases. Shoulder abduction in all patients was possible up to 90° and has decreased around 15±10° postoperatively. CONCLUSIONS: The division of the thoracodorsal pedicle and the consecutive loss of the latissimus as a reconstructive option remain challenging. The lower shoulder girdle muscles (infraspinatus, subscapularis, teres minor and major) are an adequate alternative for filling residual empyema spaces. The constraint in shoulder movement is minor and acceptable in such situations.

Marfan Syndrome: when to operate TAA(A)s?

Marfan Syndrome is a heritable disorder of connective tissue leading to aortic aneurysms and other cardiovascular complications associated with reduced life expectancy. Marfan patients with thoracic aortic aneurysms (TAAs) or with thoracoabdominal aortic aneurysms (TAAAs) should be treated by means of open surgery, requiring an extensive protocol, including extracorporeal circulation, neuromonitoring and adjunctive modalities to provide organ protection. Then, open surgical repair of TAA(A)s are associated with excellent results. However, in the last time a gradual change to endovascular treatment in Marfan patients is observable. Particularly in patients with an increased surgical risk due to redo sternotomy or thoracotomy, endovascular treatment might be an alternative due to its less invasive approach. Consequently, thoracic endovascular aortic repair comprises a therapeutic alternative in individual situations even in Marfan patients, when the landing zones are safe and appropriate. In cases of failed endovascular therapy, however, conversion to open surgery remains still an option with acceptable results, although the distal and proximal clamping positions change inappropriate with larger extensions due to the aortic stent.

Modified technique for thoracomyoplasty after posterolateral thoracotomy.

OBJECTIVE: Thoracomyoplasty after prior posterolateral thoracotomy (PLT) remains a challenge for the thoracic surgeon. Thoracodorsal artery division after PLT impairs the vascularization supply of the latissimus dorsi muscle (LDM) resulting in muscle mass reduction due to distal atrophy. This makes adequate filling of residual empyema space and/or surgical closure of bronchial stump insufficiency more difficult, and they require alternative surgical procedures. We present an alternative approach using a four-muscle flap technique to include the infraspinatus, the subscapularis and the teres major muscle group, all pedicled from the subscapular artery as a part of a modified thoracomyoplasty technique for closing residual empyema space and bronchial stump insufficiency. METHODS: Between 2002 and 2008 we performed the technique in 7 patients with residual empyema space. Three patients had post-tuberculosis syndrome, 2 had postpneumectomy empyema, and 2 had chronic parapneumonic empyema. Three cases were combined with a bronchopleural fistula. All patients underwent a two-stage procedure. First, open window thoracostomy was performed followed by definitive surgical treatment after 3-6 months. In all cases with bronchial insufficiency the stump was covered with a subscapularis muscle flap. The infraspinatus and the teres muscle group were used in combination with a local thoracoplasty. RESULTS: Mean age was 68 +/- 7.9 years. Time from open window thoracostomy to thoracomyoplasty averaged 4 +/- 1.3 months. The number of resected ribs ranged between 4 and 8. Mean postoperative stay in the ICU was 3 +/- 2.9 days. The thoracic drains were removed after 5 +/- 2.3 days. Total hospital stay was 15 +/- 7.6 days. No hospital mortality was noted. Minor postoperative complications occurred in 2 cases. Shoulder function without pain allowed abduction up to 90 degrees. Function was decreased by 16 +/- 9 degrees compared to preoperative evaluation. No severe progressive scoliosis was noted. CONCLUSIONS: Division of the LDM and its vascular supply after posterolateral thoracotomy results in a reduction of muscle mass. The shoulder girdle muscles offer an adequate alternative to fill residual empyema space with acceptable long-term results and restriction in shoulder motion. In all cases with bronchial fistula, bronchial stump closure with a pedicled subscapular muscle was an effective alternative operative technique.

Hypothermia exerts negative inotropy in human atrial preparations: in vitro-comparison to rabbit myocardium.

AIM: We investigated the effect of mild hypothermia on the contractility and calcium response of atrial and ventricular myocardium. METHODS: Human atrial tissue was excised during cannulation process from patients undergoing elective open heart surgery following informed consent. Trabeculae were carefully dissected and compared to rabbit atrial and ventricular trabeculae. All probes were electrically stimulated while clamped to a force transducer and suspended in buffer media. Developed force, time to peak tension and time to 50% of relaxation were measured during mild hypothermia (37-31 degrees C). SR Ca++-content was studied by rapid cooling contractures, Ca++-responsiveness by a stepwise increase of extracellular calcium concentration to 10 mM. RESULTS: Hypothermia decreased twitch tension and SR Ca++-content in human atrial myocardium but increased contractility and SR Ca++-content in rabbit atrial and rabbit ventricular myocardium. Cooling induced a lengthening of contraction and relaxation times in all preparations. In all preparations the positive inotropic response to calcium was diminished at 34 degrees C and almost abolished at 31 degrees C. CONCLUSIONS: In contrast to rabbit ventricular and atrial myocardium, human atrial myocardium showed a negative inotropic effect when exposed to hypothermia. This alteration could be secondary to a declined SR-Ca++ storage and decreased atrial calcium sensitivity. Calcium dependent inotropy is suppressed at temperatures below 34 degrees C.

Surgical management of a left main stem coronary artery aneurysm.

Left main stem aneurysms are rarely described and the optimal treatment is controversially discussed. A majority of these patients undergo medical treatment with antiplatelet or anticoagulation drugs. Surgery is just recommended in symptomatic patients or when there is the risk of thromboembolic events or rupture. We report on a 51-year-old patient suffering from intermittent angina pectoris in whom an aneurysm of the left main stem was diagnosed by coronary angiography. The patient underwent successful surgical management with aneurysm closure and reconstruction of the left main stem by a segment of the great saphenous vein. This report summarizes the main treatment options for left main stem aneurysms and discusses the role of cardiac surgery for this rare disease.

Inhaled iloprost to control pulmonary artery hypertension in patients undergoing mitral valve surgery: a prospective, randomized-controlled trial.

BACKGROUND: Pulmonary hypertension (PHT) is common in patients undergoing mitral valve surgery and is an independent risk factor for the development of acute right ventricular (RV) failure. Inhaled iloprost was shown to improve RV function and decrease RV afterload in patients with primary PHT. However, no randomized-controlled trials on the intraoperative use of iloprost in cardiac surgical patients are available. We therefore compared the effects of inhaled iloprost vs. intravenous standard therapy in cardiac surgical patients with chronic PHT. METHODS: Twenty patients with chronic PHT undergoing mitral valve repair were randomized to receive inhaled iloprost (25 microg) or intravenous nitroglycerine. Iloprost was administered during weaning from cardiopulmonary bypass (CPB). Systemic and pulmonary haemodynamics were assessed with pulmonary artery catheterization and transoesophageal echocardiography. Milrinone and/or inhaled nitric oxide were available as rescue medication in case of failure to wean from CPB. RESULTS: Inhaled iloprost selectively decreased the pulmonary vascular resistance index after weaning from CPB (208 +/- 108 vs. 422 +/- 62 dyn.s/cm(5)/m(2), P<0.05), increased the RV-ejection fraction (29 +/- 3% vs. 22 +/- 5%, P<0.05), improved the stroke volume index (27 +/- 7 vs. 18 +/- 6 ml/m(2), P<0.05) and reduced the transpulmonary gradient (10 +/- 4 vs. 16 +/- 3 mmHg, P<0.05). In all patients receiving inhaled iloprost, weaning from CPB was successful during the first attempt. In contrast, three patients in the control group required re-institution of CPB and had to be weaned from CPB using rescue medication. CONCLUSIONS: In patients with pre-existing PHT undergoing mitral valve surgery, inhaled iloprost is superior to intravenous nitrogylycerine by acting as a selective pulmonary vasodilator, reducing RV afterload and moderately improving RV-pump performance.

[MRI of the heart following implantation of a left ventricular apico-aortic conduit]. / Kernspintomografie zur umfassenden Untersuchung des Herzens nach Implantation von linksventrikulären apikoaortalen Conduits.

PURPOSE: To investigate the potential of ECG-triggered MRI for the evaluation of postoperative anatomy and function of the heart and conduit following implantation of a left-ventricular apico-aortic conduit. MATERIALS AND METHODS: 5 patients (2 female, 3 male, mean age 72.5 years) were examined using a 1.5 Tesla whole-body MRI (Gyroscan Intera, Philips Medical Systems, Best, The Netherlands) following apico-aortic conduit surgery due to severe aortic valve stenosis. The reason for performing conduit implantation instead of aortic valve replacement was the risk of injuring a bypass graft from prior coronary artery bypass surgery. Cine steady-state-free-precession (SSFP) sequences were used to assess ventricular function, navigator-gated 3D-SSFP and breath-hold, time-resolved contrast-enhanced MR angiography was used to display the postoperative anatomy, and 2D-gradient echo sequences with an inversion pulse to suppress the signal of the healthy myocardium were used to evaluate potential myocardial scarring. Flow sensitive gradient echo sequences were performed to determine the blood flow in the conduit. RESULTS: In all patients the apico-aortic conduit proved to be open with a maximum flow velocity of 126 (+ 43) cm/s. The postoperative anatomy was able to be evaluated in all patients and perioperative myocardial infarction was able to be ruled out. The mean ejection fraction of the left ventricle was 44.2 + 6.2 % with a mean volume of 80 + 20.6 ml per heart beat. CONCLUSION: ECG-triggered MRI is a reliable method for the evaluation of postoperative anatomy and function following implantation of a left ventricular apico-aortic conduit.

[The cardiac surgeon's role in intensive care]. / Intensivmedizin aus Sicht des Herzchirurgen.

During recent years there has been an ongoing process of profound change in German hospitals to save money because of governmental directives. This is also true for the management of hospitals and their departments, leading to new interdisciplinary wards. Therefore this article discusses the management of intensive care units from the cardiac surgeon's view and presents the "Aachen Model" as a possible solution.

Intrathoracic implantation of a continuous flow left ventricular assist device--the microdiagonal blood pump.

AIM: All existing ventricular assist devices are associated with a considerable number of serious complications. We report on our first animal tests with a newly developed microdiagonal blood pump (MDP). METHODS: Six female calves underwent MDP implantation. The inflow and outflow conduit were anastomosed to the left atrium and the descending aorta. The MDP was placed in the left phrenicocostal sinus. Pump flow was adjusted to 2-3 L/min. Hemodynamic and echocardiographic data as well as blood samples were measured over the test period of 7 days. Thereafter, all internal organs and the pump were explanted for thorough examination. RESULTS: Mean arterial (90.5+/-12.1102.7+/-8.7 mmHg) and mean pulmonary arterial (17.3+/-2.420.6+/-2.7 mmHg) pressures remained stable during the test period. Cardiac output (5.4+/-0.5 = or >3.5+/-0.5 L/min) decreased postoperatively due to partial unloading of the heart. Left ventricular end-diastolic (4.4+/-0.5= or >3.8+/-0.4 cm) and end-systolic (3.4+/-0.5 =or >2.9+/-0.4 cm) diameters decreased after MDP implantation and did not change during the test period. Mean number of platelets (550+/-57 =or >350+/-86 x 103/microL) and hemoglobin (13.2+/-1.3 = or >11.9+/-0.8 g/dL) decreased perioperatively due to surgical reasons and recovered in the postoperative course. Free hemoglobin was slightly enhanced in the postoperative course. CONCLUSION: Our results demonstrate that the MDP is suitable for intrathoracic implantation and provides a reliable left ventricular unloading.

APOE alleles are not associated with calcific aortic stenosis.

OBJECTIVES: To analyse the association of APOE alleles with aortic stenosis (AS) in a large study population. METHODS: Patients with AS (n = 538) and a control group of the same age without heart disease (n = 536) were recruited. Left heart catheterisation was performed and mean gradient, aortic valve area, presence of stenotic coronary artery disease (CAD) and cardiovascular risk factors (hypercholesterolaemia, hypertension, smoking, diabetes mellitus and family history of CAD) were assessed. The frequency of the APOE major alleles e2, e3 and e4 was assessed by genotyping the polymorphisms APOE334 and APOE472 with a 5' exonuclease assay (TaqMan). RESULTS: Mean gradient across the aortic valve in cases was 50 (SD 20) mm Hg corresponding to a mean aortic valve area of 0.84 (SD 0.34) cm(2). 270 patients with AS had stenotic CAD. Among patients with AS, the prevalence of hypercholesterolaemia (64% v 40%, p < 0.001), smoking (43% v 27%, p < 0.001), diabetes (27% v 17%, p < 0.01), family history of CAD (30% v 21%, p 0.10). CONCLUSION: APOE e4 is not associated with AS, reflecting the different genetic backgrounds of CAD and AS.

Perioperative risk of aortic valve replacement after coronary artery bypass grafting.

OBJECTIVE: To evaluate the operative risk of aortic valve replacement (AVR) after coronary artery bypass grafting (CABG). METHODS: Twenty patients (sixteen male, four female) underwent AVR 1.5-20 years (mean: 8.2) after CABG. RESULTS: Patients had received a mean number of four bypass grafts (2-5) with the use of the left internal thoracic artery in seventeen patients. Mean age at the time of AVR was 70.5 years (57-82). All patients suffered from an aortic stenosis with a mean orifice area of 0.74 cm (2) (0.34-1.1) and a mean pressure gradient of 52.4 mm Hg (22-78). Ten mechanical (mean diameter 23.6 mm, 21-27) and ten biological (22.1 mm, 19-25) prostheses were implanted. Mean duration of surgery, cardiopulmonary bypass (CPB) and cross-clamp time were 322.1 (205-645), 169.2 (87-411), and 77.1 (46-128) minutes, respectively. Fourteen patients had an uneventful postoperative course. A temporary neurological impairment, renal failure, and re-intubation for respiratory insufficiency for nine hours occurred in one patient each. Two patients died postoperatively (day 3 and 10) due to multiple cerebral infarctions. One patient required a replacement of the ascending aorta in deep hypothermia and re-implantation of the bypasses. He suffered from gastrointestinal bleeding on postoperative day 14 and expired on day 81 because of multi-organ failure. CONCLUSION: Aortic valve replacement after coronary artery bypass grafting is associated with an enhanced perioperative risk requiring meticulous decision-making and a sophisticated operative technique.

Impact of pressure recovery in the evaluation of the Omnicarbon tilting disc valve.

BACKGROUND: Pressure recovery is not taken into account when calculating trans-prosthetic gradients after mechanical valve replacement using Doppler echocardiography. This may lead to underestimation of valvular performance. METHODS: Simultaneous measurement of Doppler and direct trans-prosthetic gradients was performed in a circulatory mock loop simulator with physiologic parameters at different heart rates and cardiac outputs for small-sized aortic Omnicarbon tilting disc valves (19 - 21 mm). RESULTS: In all adjustments the Doppler gradient significantly overestimated the net transvalvular gradient. The amount of pressure recovery averaged 59.3 %. CONCLUSIONS: Doppler echocardiography does not allow for pressure recovery, which is a significant phenomenon in the hemodynamic function of the Omnicarbon tilting disc valve. Valve performance is much better than expected from Doppler gradients.