Successful weaning from extracorporal circulation using a pumpless extracorporal lung assist device in a patient with intraoperative hypercapnic lung failure during aortic valve replacement.

We present a case of a 59-year-old female suffering from massive pulmonary edema with consecutive hypercapnic lung failure immediately following elective aortic valve replacement. Due to severe restrictive ventilation disorder, mechanical ventilation was inadequate. A pumpless lung assist (PECLA, iLA, Novalung®, Talheim, Germany)--a device for extracorporeal carbon dioxide elimination--was used for successful weaning from extracorporeal circulation (ECC). Within 24 hours respiratory function had normalized and the patient could be extubated. The further clinical course and follow-up at 3 months remained uneventful. This report describes the first intraoperative use of the PECLA device in a cardiac surgery patient to promote weaning from ECC.

Female gender does not increase perioperative risk in coronary bypass surgery.

INTRODUCTION: Female gender has been identified as an independent risk factor for perioperative mortality in several risk scores for cardiac surgery. Since no explanation has been given for this, this study aimed to evaluate potential differences in the distribution of other risk factors between the genders. PATIENTS AND METHODS: 10 714 consecutive coronary bypass patients were analyzed retrospectively. The distribution of the risk factors as used in the EuroSCORE was evaluated. Diabetes mellitus was added to the analysis as an additional risk factor. Patients aged between 60 and 70 years without any additional risk factors were directly compared in a subgroup analysis. Statistical analysis was done using the T-test or chi-square test where appropriate. RESULTS: Female patients were significantly older compared to male ones (69.1 ± 8.5 vs. 65.4 ± 4 years, P < 0.05). The distribution of the analyzed risk factors did not differ except for diabetes mellitus: female patients were more likely to present with diabetes (42 % vs. 29 %, P < 0.05) and in diabetic patients, the incidence of insulin dependency was higher in female patients (50 % vs. 33 %, P < 0.05). Overall perioperative mortality was higher in female patients (2.7 % vs. 1.8 %, P < 0.05). This difference increased when diabetes was present (3.9 % vs. 1.8 %, P < 0.05) and was even higher in insulin-dependent patients (4.9 % vs. 1.9 %, P < 0.05). However, when adjusting for age and diabetes, the differences were reduced. This was most evident when subgroups of age-adjusted patients without any additional risk factors were analyzed: no gender-specific difference in perioperative mortality was observed. CONCLUSIONS: Female gender itself did not present as an independent risk factor. The presence of diabetes mellitus increased the risk in female patients significantly more than in male patients. The higher prevalence of diabetes in female patients in combination with the older age at presentation might result in the higher overall mortality observed in female patients compared to men.

Preoperative platelet inhibition with ASA does not influence postoperative blood loss following coronary artery bypass grafting.

INTRODUCTION: Platelet inhibition is thought to increase perioperative blood loss in patients with planned coronary artery bypass grafting (CABG). This retrospective study reviews the results of over 10 000 patients with CABG, comparing continued platelet inhibition with preoperative disruption of this therapy. PATIENTS AND METHODS: From 1995 to 2007, 12 023 patients underwent isolated CABG and were included in this study. The data were evaluated with regard to preoperative aspirin therapy, EuroScore relevant risk factors, and the operative results. Parameters of the operative outcome were in-hospital mortality, perioperative infarctions, reexploration rate, strokes, pericardial tamponade, blood transfusions, and perioperative drainage loss. RESULTS: The patients were divided into two groups: group A (continuous aspirin therapy till surgery [n = 2519]), and group B (patients with preoperative interruption of their aspirin therapy for at least five days [n = 9504]). There was no difference between the groups with regard to age, EuroScore (4.3 +/- 2.8 vs. 4.2 +/- 2.9), emergency cases (8.8 % vs. 8.7 %), left main stenoses (17.9 % vs. 17.6 %), duration of surgery (198 +/- 53 vs. 198 +/- 52 min.) and sex distribution. The postoperative drainage loss did not differ between groups A and B (834 +/- 781 ml vs. 902 +/- 811 ml), nor did the number of postoperatively administered red cell packages (0.88 +/- 2.7 vs. 1.01 +/- 2.9). When analyzing the three subgroups "on-pump primary CABG", "OPCAB procedures", and "redo CABG", again no difference was found in the main outcome parameters. Only the redo CABG of group B had a higher reexploration rate compared to group A (5 % vs. 3.3 %, P < 0.05). CONCLUSION: Preoperative aspirin therapy does not seem to influence the operative outcome of isolated CABG. Therefore, the often given recommendation to stop this therapy prior to elective CABG procedures should be abandoned.

Combined cardiac surgical procedures in octogenarians: operative outcome.

INTRODUCTION: The number of patients with an indication for cardiac surgery in their ninth decade of life is increasing. This study analyses the single-center results with combined and redo cardiac surgical procedures in octogenarians retrospectively. PATIENTS AND METHODS: Three groups were evaluated: (I) Two hundred and thirty six patients with combined cardiac surgical procedures, mean age 83.1 +/- 2.5 years, 107 male (129 female). Combined aortic valve replacement (AVR) and aorto coronary bypass (ACB) was done in 215, double valve replacement (DVR) in 21. (II) AVR + ACB-group: 215 patients out of group I. (III) Control group consisting of 124 patients with a mean age of 74.1 +/- 2.8 years (range 70-79.9 years) who received combined AVR and ACB. Risk stratification was done using the additive and logistic Euro-score; values are given as mean +/- standard deviation and were compared using either the t-test or the Chi-square test. RESULTS: The observed mortality in group I was 9.3%. Re-intubation was observed in 10.2% and was one major risk factor for in-hospital mortality. As second risk factor, DVR could be identified. 14.8% required hemodialysis postoperatively, but this affected only the length of stay on intensive care unit (ICU) but not mortality. When comparing group II with group III, mortality was higher (10% vs. 4%), the need for hemodialysis was more frequent (16.3% vs. 4.9%), and the incidence of postoperative psycho-syndromes was also higher (26% vs. 8.1%, all: P < 0.05). The duration of ventilation (2.7 +/- 7.7 vs. 1.6 +/- 4.3 days) and the length of stay on ICU (8.2 +/- 8.8 vs. 5.7 +/- 6.4) were longer without reaching statistical significance (P > 0.05). The Euro-score overestimated the real mortality in all groups. CONCLUSIONS: Octogenarians requiring combined cardiac surgical procedures required more resources and had a higher in-hospital mortality compared to younger patients. The observed in-hospital mortality was much lower than the predicted justifying the indication for surgical therapy in these patients. Patient selection, however, seems to be important but the Euro-score alone was rather ineffective in predicting poor outcome.

Safety of a cardiac surgical training program over a twelve-year period.

INTRODUCTION: The operative results of cardiac surgical procedures performed either by staff surgeons or trainees were compared to evaluate whether there is any additional risk to the patient in operations carried out by trainees. PATIENT AND METHODS: Between 1994 and 2006, 13 197 operations were done by 9 staff surgeons (S-group) and were compared to 1925 operations performed by 10 residents during their training program (R-group). In both groups, subgroups were defined in which patients either underwent isolated coronary artery bypass grafting (CABG) or aortic valve replacement (AVR). Isolated CABG was performed in 8725 cases (S-group) and 1706 cases (R-group). AVR was done in 1273 patients (S-group) and 191 patients in the R-group. The groups were compared with regard to length of surgery, in-hospital mortality, reexploration for bleeding, sternal wound complications, preoperative infarction and stroke. For overall risk stratification, the EuroSCORE was used. In the CABG groups, the KCH score was additionally used. RESULTS: Overall mortality was 0.5 % in the R-group (predicted mortality: 4.6 +/- 5 %) compared to 2 % in the S-group (predicted mortality: 6.9 +/- 7.9 %). Analyzing the CABG groups, mortality was 0.7 % in the R-group (predicted: 1.9 +/- 1.8 %) compared to 1.3 % in the S-group (predicted: 2.1 +/- 2.3 %). The rate of reexplorations for bleeding was 1 % in the R-group compared to 2 % in the S-group ( P < 0.05). Duration of extracorporeal circulation (ECC) was slightly longer in the R-group (95.8 +/- 33 compared to 85.5 +/- 28.3 minutes) without reaching statistical significance ( P > 0.05). Analyzing the AVR group, there was a 0.6 % mortality in the R-group (predicted: 6.5 +/- 6 %) compared to 3.1 % in the S-group (predicted: 8.8 +/- 8 %). Again, there were significantly more reexplorations for bleeding in the S-group (0.6 % vs. 2.8 %, P < 0.05). Time on ECC was longer in the R-group (101.6 +/- 21.6 vs. 96.6 +/- 35 minutes) with a resulting longer cross-clamping time (71.2 +/- 17.1 vs. 63.5 +/- 21 minutes). CONCLUSIONS: Training in cardiac surgery can be done with excellent results and no additional risk to the patients. Both groups performed similarly and had outcomes better than the predicted mortality. Training was mostly performed with isolated coronary artery bypass grafting procedures, resulting in only a small surgical spectrum at the time of board certification.

Mechanical aortic and mitral valve replacement in infants and children.

BACKGROUND: The aim of this study was to evaluate early and late outcomes after mechanical systemic heart valve replacement in pediatric patients. METHODS: Between October 1981 and December 2003, 32 children (mean age 7.2 +/- 5.4 years; 4 months - 15.9 years) underwent mechanical mitral (MVR, n = 17), aortic (AVR, n = 13) or double valve replacement (DVR, n = 2) with St. Jude Medical valves. Twenty-two patients (69 %) had undergone previous cardiac surgery. Anticoagulation self-management was used since 1995. RESULTS: The operative mortality was 3.1 %. Perioperative complications were complete heart block (n = 5), ventricular fibrillation (n = 1) and myocardial infarction (n = 1) and were exclusively related to patients with MVR. Mean calculated valve size ratio (geometric prosthesis orifice area/normal valve size area) was 1.72 (1.07 - 2.85) for AVR and 1.4 (0.88 - 3.12) for MVR. Mean follow-up was 9.1 +/- 6.6 years (range 0.4 - 23.2 years, cumulative 283 patient-years). There were two late deaths in patients with MVR. Actuarial survival after 10 years was 93.8 %. Late complications were endocarditis (n = 2), minor hemorrhagic event (n = 1), and stroke (n = 1). Anticoagulation self-management is well accepted by all patients/parents. Overall 10-year freedom from any anticoagulation-related adverse event with phenprocoumon was 89.1 % (1.2 %/patient year). Nine patients required reoperations: redo-MVR (outgrowth of prostheses (n = 3), pannus overgrowth (n = 2), closure of paravalvular leak after AVR (n = 2), partial aortic valve thrombosis (n = 1) and redo-DVR (n = 1 for endocarditis). Freedom from reoperation after 10 years was 80.9 %. CONCLUSIONS: Mechanical valve prostheses are a valuable option for left-sided heart valve replacement in pediatric patients. Perioperative morbidity was exclusively related to patients with MVR. Oversizing was often possible to avoid early reoperation for outgrowth. The operative mortality and long-term morbidity are acceptable. Anticoagulation self-management is safe and well accepted.

Systemic mechanical heart valve replacement in children under 16 years of age.

UNLABELLED: We report the early and late outcome following left-sided mechanical heart valve replacement in children. Between 10/1981 and 02/2001, 27 children (13 male, mean age 7.2 +/- 5.2 years, range 0.53-15.7 years) underwent mechanical mitral (MVR 16), aortic (AVR 9) or double valve replacement (DVR 2) with St. Jude Medical valves. Eighteen children (66.7%) had undergone previous cardiac surgery. Valve disease was congenital in 23, due to endocarditis in 2 and rheumatic in 2 patients. Concomitant cardiac surgery was performed in 12 patients (44.4%). Operative mortality was 3.7% (1/27). Perioperative complications were complete heart block (5) and myocardial infarction (1). Mean follow-up was 6.5+/-5.9 years (range 0.4-19 years, total 169.9 patient-years). There was one valve-related late death due to mitral valve thrombosis without phenprocoumon. Actuarial survival after 1, 5 and 10 years was 93, 93 and 93%. Late complications included endocarditis (2), minor hemorrhagic event (1) and stroke (1). Overall 10-year freedom from any anticoagulation-related adverse event under phenprocoumon was 91% (1.3%/patient year). Eight patients required reoperations: re-MVR (5; outgrowth of the prostheses (3), pannus overgrowth (2)), closure of paravalvular leak after AVR (2), and re- DVR (1; endocarditis). Actuarial freedom from reoperation after 1, 5 and 10 years was 96, 88 and 76%. CONCLUSION: Mechanical valve prostheses are a valuable option for left-sided heart valve replacement in pediatric patients with good results. Operative mortality and the incidence of any valve-related events as endocarditis, reoperation, thromboembolism or anticoagulation related bleeding is acceptable.

Cardiac surgery in a patient with haemophilia A.

In this report we describe the successful cardiac surgery in a patient with haemophilia A. To undergo to triple on-pump coronary artery bypass grafting the level of factor VIII was estimated to be 100 %, during the operation and the first postoperative week. To reach this level, bolus therapy with B-domain deleted recombinant factor VIII was administered in a low substitution scheme. There was no bleeding complication. The patient discharged on the 14th postoperative day.

Seeding of human vascular cells onto small diameter polyurethane vascular grafts.

INTRODUCTION: Thrombogenicity of small diameter vascular prostheses might be reduced by complete coverage of the luminal surface with vascular cells. We investigated cell seeding on polyurethane vascular prostheses (PUVP). METHODS: 45 PUVP were divided into three groups of n = 15 each: Group A (diameter 20 mm, gamma-sterilized), Group B (diameter 4 mm, gamma-sterilized), and Group C (diameter 4 mm, ethylene oxid [Eto]-sterilized). Human smooth muscle cells (SMC), fibroblasts (FB), and endothelial cells (EC) were isolated from saphenous vein segments and expanded in culture. PUVPs were pre-seeded with a mixed culture of FBs and SMCs (mean 7.7 +/- 2.3 x 10(6) cells) followed by EC seeding (mean 4.4 +/- 0.9 x 10(6) cells). Seven days after cell seeding, PUVPs were perfused under a pulsatile flow. Flow definitions were as follows: adaption phase: low flow, resulting pressure: 60/30 mm Hg; high flow: resulting pressure: 160/50 mm Hg, lasting for 4 hours in all groups. Three subgroups were defined out of each group, differing in the perfusion strategy: high flow immediately, adaption phase of 15 minutes followed by high flow, and adaption phase of 30 minutes followed by high flow. Specimens were taken after each seeding procedure, prior to and after perfusion, and then examined using a scanning electron microscope (SEM) and immunohistochemical staining procedures. RESULTS: Pre-seeding with the mixed culture revealed a better initial adhesion in Groups A and B compared to group C (76% vs. 41%). In Groups A and B, EC seeding (adhesion 72%) resulted in a confluent EC layer. Immunohistochemical stainings were positive for collagen IV, laminin, CD31, and factor VIII, but negative for eNOS. In Group C, only isolated cells were found after each seeding procedure, which rounded up and vanished during the next days. When perfused with high-flow immediately, Group A and B prostheses revealed small defects (< 10% of the surface) of all cell layers. After perfusion with an adaption phase of 15 minutes only few defects were found within the EC layer with an intact basement membrane. An adaption phase of 30 minutes resulted in a confluent cell layer without significant cell defects. After perfusion, the endothelial cells also stained positive for eNOS. CONCLUSION: Seeding of a mixed culture consisting of FBs and SMC resulted in an excellent EC adhesion and resistance to shear stress. Cell attachment was better on gamma-sterilized PUVPs compared to Eto-sterilization. The cells obviously maintained their ability to adapt to shear stress.

Delayed repair of stanford type-A dissection following fulminant cerebral infarction.

We report an impressive case in which a complete infarction of the right hemisphere due to an acute occlusion of the right carotid artery had developed. After cerebral decompression and neurological rehabilitation, the persisting dissection of the ascending aorta and both carotid arteries was successfully repaired in one session.

A low-flow adaptation phase improves shear-stress resistance of artificially seeded endothelial cells.

INTRODUCTION: The purpose of this study was to evaluate the effect of different adaptation phases on the shear-stress resistance of endothelial cells seeded artificially onto vascular prostheses and biological heart valves. MATERIAL AND METHODS: Human endothelial cells (EC), fibroblasts (FB), and smooth muscle cells (SMC) were isolated from vena saphena magna pieces and expanded in culture. Group A: 15 polyurethane vascular grafts (20 mm diameter) were seeded with FB and SMC (53 +/- 1.2 million cells), followed by EC seeding (39 +/- 0.9 million cells). Group B: eight stentless porcine valves (Freestyle, Medtronic, USA) were seeded with FB (68 +/- 1.5 million cells) and EC (42 +/- 1.1 million cells). Shear-stress testing was done under pulsatile flow (pulse rate: 80 pulses/min.). Adaptation phase: flow was set to 0.9 +/- 0.3 l/min (systolic pressure: 40 - 50 mm Hg). High flow was 3.2 +/- 0.6 l/min. (systolic pressure: 140 - 160 mm Hg) and lasted over four hours in all groups. The vascular grafts were divided into three groups (n = 5 each): group 1 (high flow immediately), group 2 (adaptation phase of 15 minutes), and group 3 (adaptation phase of 30 minutes). The valves either were given high flow immediately (n = 4) or had an adaptation phase of 30 minutes (n = 4). Specimens were obtained after cell seeding, before, and after perfusion. RESULTS: A confluent EC layer was achieved on all grafts. After perfusion without adaptation, large defects within the cell layer were found. No FB and SMC were seen at the bottom of these defects. In group B, the defects were largest on the ventricular surface of the leaflets. After an adaptation phase of 15 minutes in group A, only a few defects within the EC layer were detected with a still confluent FB and SMC. After a 30-minute adaptation phase defects within the EC layer were very rare and no interruption of the underlying FB and SMC layer was seen. Immunohistochemical staining for factor VIII and CD31 proved the EC to be viable and staining for collagen IV and laminin revealed the formation of a basement membrane. After perfusion, the specimen also stained positive for eNOS. CONCLUSION: An adaptation phase of 30 minutes proved to be sufficient to allow artificially seeded endothelial cells to adapt to shear stress. The formation of a basement membrane was of great importance for the maintenance of a confluent EC layer.

Myoblasts for survive 16 weeks after intracardiac transfer and start differentiation.

INTRODUCTION: Skeletal myoblasts have been shown to survive transfer into myocardial scar tissue. The purpose of this study was to investigate differentiation after intramyocardial transplantation. Additionally, we evaluated an intravital fluorescence dye. MATERIALS AND METHODS: Skeletal myoblasts were harvested from 8 male inbred Lewis rats and expanded in culture. For each transplantation planned, 10(6) cells were trypsinized and incubated for three minutes with 2 ml of buffered PKH-26 solution (Sigma, St. Louis). This dye was integrated into the cell membrane. After washing three times, the cells were plated again for two more days. The cells were then transplanted into the hearts of 60 female Lewis-rats, mean weight 380 g (260 - 450 g). At implantation, 10(6) cells suspended in 100 microliters were injected into the apex region of the left ventricle. 12 animals served as the control group with only cell medium injected. Animals were sacrificed after 1, 2, 6, 8, 12, and 16 weeks (n = 10 each). The hearts were explanted and serial frozen sections of the hearts were prepared for detecting labeled cells. Sections with labeled cells were stained immunohistochemically for Myo D1 (myogenic origin), n-cam (early myotubes), desmin (muscular filament), myosin light chain (muscular contractile protein), and connexin 43 (tight junction). RESULTS: Cell labeling was successful in all cases. After two days, the myoblasts had recovered from the staining procedure. The fluorescing dye, however, was only rarely transmitted by cell division. Marked cells were found in the intercellular spaces between the cardiac myofibers in at least 8 animals from each group. No fibrotic reaction or inflammation was seen surrounding the transplanted cells. Up to 6 weeks after implantation, the cells stained positive for n-cam and Myo D1, and particularly for desmin. More n-cam positive cells were found than labeled cells, indicating cell division after the cell transfer. Two animals suffered sudden death after a follow-up time of 8 and 10 weeks, which was possibly due to cardiac arrhythmia. After 8 weeks, the cells formed conglomerates and stained positive for desmin, myosin light chain, and connexin 43. The cells were not structurally integrated into the recipient myocardial tissue, however. CONCLUSIONS: Myoblasts divided further after transplantation into rat myocardium. Positive staining for desmin demonstrated the development of myofibers. Starting at 8 weeks after transplantation, the cells started differentiation without reaching structural integration during follow-up. Labeling the cells with PKH-26 proved to be a reliable method to detect the cells.

Five years of experience with mitral valve homografts.

INTRODUCTION: The main advantages of mitral homografts are preservation of the subvalvular apparatus and avoidance of life-long anticoagulation. In this communication, we will present our five-year experience using mitral homografts in mitral valve surgery. PATIENTS AND METHODS: Since 1996, 14 patients (mean age 46 +/- 8 years, range 27 - 65 years have had mitral homografts implanted. Thirteen patients had mitral valve replacement; the septal leaflet of the tricuspid valve was replaced in one case. The indications were mitral (n = 6) or tricuspid endocarditis (n = 1), mitral valve stenosis (n = 3), and combined mitral valve disease (n = 4). Complete mitral homografts were implanted in eight patients; partial homografts were used in six cases. Preoperatively, the dimensions of the left ventricle and the mitral valve were measured by transoesophageal echocardiography (TOE). The mean left ventricular ejection fraction was 56 +/- 9%, the mean end-diastolic diameter 58 +/- 6 mm. The technique described by Acar/Carpentier was adapted for implantation; a Carpentier ring was implanted in all cases for annular stabilization. The patients had anticoagulative therapy which was discontinued when stable sinus rhythm was present after three months postoperatively. Follow-up included clinical examination, ECG, and echocardiography, and was initiated six months postoperatively and continued on a yearly basis. The following parameters were determined by echocardiography--left atrial size, left ventricular end-diastolic and end-systolic diameter, pressure gradient across the mitral valve (c/w Doppler, Bernoulli's equation), and mitral regurgitation. RESULTS: All patients survived surgery; the mean operation-time was 281 +/- 37 minutes. Intraoperative TOE revealed a first degree insufficiency in 7 patients. Follow-up was completed in all patients, with a mean period of 30 months (6 - 60 months). Two patients had an acute endocarditis two years postoperatively, requiring repeat valve replacement with a mechanical prosthesis. An additional patient had to be reoperated due to chordal rupture three years postoperatively. All three patients had mitral valve stenosis as the initial indication for surgery and had received a complete homograft. In the remaining eleven patients, the morphological and functional state of the implanted grafts remained unchanged during follow-up. The freedom from valve-related events was 93% after one year, 86% after two years, and 79% after three years. At six-month follow-up, ECG and echocardiography revealed sinus rhythm and sufficient atrial contractions in 13 cases. At the last follow-up, the pressure gradients were 3.4 +/- 0.6 mmHg for complete homografts and 2.8 +/- 0.6 mmHg for partial homografts. In five cases, a mild insufficiency was documented, while six patients presented with competent grafts. CONCLUSIONS: Mitral homografts can be used with acceptable mid-term results in selected cases with good left ventricular function and only slightly dilated left ventricles. Partial mitral homografts represent an additional technique, especially for mitral valve repair in patients with acute endocarditis. The susceptibility to bacterial infections of a homograft makes strict prophylaxis against endocarditis mandatory.

Homografts in patients with combined disease of the aortic valve and the ascending aorta: an alternative to the classical Bentall procedure.

BACKGROUND AND AIM OF THE STUDY: In patients with aneurysms or dissections of the ascending aorta and additional aortic valve disease, valve-containing composite grafts are used in clinical routine. The study aim was to present our experience with homografts for aortic valve replacement extended by a vascular prosthesis as an alternative to the classical Bentall procedure. METHODS: Thirty consecutive patients (mean age 46+/-14 years) were included in this study. Indications for valve replacement were aortic stenosis (n = 15), aortic insufficiency (n = 6), combined aortic valve disease (n = 6), endocarditis of the native valve (n = 1), and endocarditis of a previously placed bioprosthesis (n = 2). The mean diameter of the ascending aorta was 5.6+/-0.5 cm; one patient had an acute dissection (diameter 4.4 cm). For valve replacement, cryopreserved homografts (mean size 24+/-2 mm) were used in a mini-root technique, and the ascending aorta was replaced by collagen-coated vascular prostheses (mean diameter 28+/-3 mm). The size of the vascular prosthesis was adjusted to the diameter of the sinutubular junction of the implanted homograft. Follow up included annual clinical examinations, transthoracic echocardiography and ultrafast computed tomography (CT) scans. RESULTS: All patients survived surgery, and no deaths occurred during follow up. None of the patients had postoperative anticoagulation, and no thromboembolic events were noted. Follow up was complete, with an average 48 months (range: 6 to 84 months). Doppler echocardiography revealed trivial to mild aortic regurgitation in nine patients postoperatively, with no deterioration during follow up. No pathologic pressure gradients over the aortic valves were measured at Doppler echocardiography; the mean valvular orifice area was 2.5+/-0.3 cm2. At ultrafast CT, normal homograft anatomy including the sinotubular junction, no calcifications, and no signs of annular dilatation were seen. In the patient who had surgery for acute endocarditis of the native valve, ultrafast CT revealed a small pseudoaneurysm below the left coronary artery, without need for reoperation. CONCLUSION: Short- and mid-term results show that cryopreserved homografts extended by small-sized vascular prostheses can be used safely for Bentall procedures in selected cases where the diameter of the aortic valve annulus is moderately dilated.

Pseudoaneurysm complicating homograft aortic valve replacement--two different--courses and strategies.

The courses of two patients with pseudoaneurysm formation following aortic valve replacement using homografts are reported. Both patients had aortic valve replacement due to acute infective endocarditis with paravalvular abscess formation. The first case had an uneventful postoperative course; but on routine echocardiography, a pseudoaneurysm located at the left coronary commissure was found at one year follow-up. As the pseudoaneurysm was completely asymptomatic, the patient was followed up carefully at six months intervals. The second patient also had pseudoaneurysm formation postoperatively, but he presented one year after surgery with fever and elevated leucocyte count. He had surgical revision of the pseudoaneurysm because no other reason for an infection could be found. Four months later he presented again with infection signs and pseudoaneurysm formation. This time, the homograft was completely excised and another homograft was implanted. One year after the final operation, he is now free from re-infection. The two presented courses show that pseudoaneurysms complicating aortic valve replacement should be managed according to attendant circumstances and symptoms.

Clinical use of a computer-enhanced surgical robotic system for endoscopic coronary artery bypass grafting on the beating heart.

The aim of the study was to perform endoscopic coronary artery bypass grafting on the beating heart using a surgical robotic system. In the study, the surgical system ZEUS was used in combination with 3D visualization for endoscopic coronary artery bypass grafting in 25 patients. In a total of 10 cases, the coronary artery anastomosis was done on the beating heart using endoscopic stabilizers without cardiopulmonary bypass. In all cases, total OR time ranged from 4.0 to 8.0 hours (median 5.5 h); the times for endoscopic coronary artery anastomoses ranged from 14 to 50 minutes (median 25 minutes) with no difference between arrested-heart or beating-heart procedures. All patients had an uneventful angiographic control result. An endoscopic coronary artery anastomosis is possible on the arrested as well as on the beating heart.

[Pseudoaneurysm after Bentall's procedure in acute aortic dissection type A: diagnosis using electron beam tomography]. / Pseudoaneurysma nach Bentall-Operation bei Versorgung einer Typ A-Dissektion: Diagnosefindung durch Elektronenstrahl-Tomographie.

Pseudoaneurysms are a rare complication following replacement of the ascending aorta or aorto-coronary bypass surgery. We report a case with replacement of the aorta ascendens, the aortic valve, and venous aorto-coronary bypass grafting, in whom a pseudoaneurysm developed at the site of one proximal bypass anastomosis. For the preoperative diagnosis, an ultrafast-CT (Electron Beam Tomography, EBT) was done, as neither the pseudoaneurysm, nor the venous graft could be visualized by selective coronary angiography.

Three-dimensional video and robot-assisted port-access mitral valve operation.

BACKGROUND: In order to minimize surgical trauma, video-assisted mitral valve operation has been started using the Port-Access technique with the addition of a three-dimensional visualization system (Vista Cardiothoracic Systems Inc, Westborough, MA) and a voice-controlled camera-holding robotic arm (Aesop; Computer Motion Inc, Goleta, CA). METHODS: Port-Access mitral valve replacement or repair (PAMVR) was undertaken using an endovascular cardiopulmonary bypass (CPB) system. Fifty patients underwent Port-Access mitral valve replacement or repair. A three-dimensional thoracoscope was inserted allowing complete three-dimensional projection of the mitral valve (Vista). In the last 20 patients, the camera was attached to a robotic arm (Aesop), which allowed stabilization and voice-activated movement of the camera. Mitral valve repair was performed in 26 patients, and the valve was replaced in 24 patients with a mechanical valve prosthesis. RESULTS: Median time of operation was 4.2 hours, aortic cross-clamp time 83 minutes, CPB time 125 minutes, intensive care unit stay 1.5 days and hospitalization 9.0 days. Three months follow-up was complete in 40 patients, with 34 patients (85%) in New York Heart Association class I and 6 patients in class II. Mortality was 0% and rate of reoperation was 2%, with a follow-up time up to 1.5 years postoperatively. CONCLUSIONS: Using three-dimensional video and robotic assistance, it was possible to minimize the length of skin incision, but at the same time to optimally visualize the whole mitral valve apparatus in order to perform true Port-Access mitral valve operation, including various repair techniques.

Tumors of the cardiac valves: imaging findings in magnetic resonance imaging, electron beam computed tomography, and echocardiography.

We describe the findings from various cross-sectional imaging modalities in patients with cardiac valve adherent masses. The techniques are discussed, and imaging findings are compared with the results of cardiac surgery. All three patients had neurological symptoms and/or cardiac murmurs. Transthoracic and/or transesophageal echocardiography revealed the cardiac mass in all three. For differentiation of thrombus and cardiac neoplasm magnetic resonance imaging (MRI) was also performed in all three patients and electron-beam computed tomography (EBCT) in two. Fast segmented cine gradient-echo MRI techniques provided mass depiction in all patients, while T1-weighted spin-echo imaging failed in mass detection in one patient. None of the patients showed evidence of valve regurgitation or stenosis in flow sensitive cine MRI. EBCT excluded mass calcifications in both patients and reliably demonstrated the valve attached lesions. Although echocardiography is the modality of choice in evaluating cardiac masses and especially valve attached masses, MRI and EBCT provide additional information about tissue characteristics and allows an excellent overview of the cardiac and paracardiac morphology. Fast segmented cine gradient-echo MRI is especially able to depict even small tumors attached to rapidly moving cardiac valves, and valve competence can be easily assessed within the same examination.

Mitral valve surgery utilizing homografts: early results.

BACKGROUND AND AIM OF THE STUDY: Mitral valve repair is superior to prosthetic valve replacement due to preservation of the subvalvular apparatus. We used cryopreserved homografts for mitral valve replacement in selected cases, in whom valve repair would not have been successful. METHODS: Cryopreserved homografts were used in 10 patients (four males, six females; mean age 47 +/- 8 years; range: 27-65 years), for either complete (n = 7) or partial (n = 3) mitral valve replacement. Surgery was indicated due to acute endocarditis (n = 3), stenosis (n = 4) or combined mitral valve disease (n = 3). Transesophageal echocardiography (TEE) was performed to determine correct homograft size; these values were compared with intraoperative measurements of valvular dimensions. The function of the implanted grafts was examined intraoperatively by TEE. Follow up included clinical examination, electrocardiography and echocardiography. RESULTS: All patients survived surgery. Intraoperative TEE revealed mild insufficiency (grade I) in six cases and no insufficiency in four. The papillary muscle-mitral annulus distance was the most reliable preoperative echocardiographic parameter to determine the required homograft. Mean pressure gradients were 3.2 +/- 0.7 mmHg for complete and 2.4 +/- 0.5 mmHg for partial homograft replacement. Sinus rhythm was present in all cases at discharge. Mean follow up was 24 months (range: 6-36 months). At six-month and one-year follow up, the pressure gradients had risen slightly to 3.4 +/- 0.6 mmHg (complete) and 2.8 +/- 0.6 mmHg (partial). To date, four patients had competent grafts, and six presented with an insufficiency (grade I). All patients had normal left ventricular function (EF 65 +/- 6%) at their last follow up; there were no signs of endocarditis during the follow up period. CONCLUSION: Mitral homografts for valve replacement or repair are recommended in selected cases in whom conservative reconstruction techniques are not possible. The avoidance of long-term anticoagulation therapy and preservation of left ventricular geometry are clear advantages to other mitral valve prostheses.