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The current study examines the role of action-depicting gestures in conversational turns by focusing on their semantic characteristics and temporal position in relation to their verbal affiliates (action verbs or more complex verb phrases). The data are video recordings of naturally occurring interactions in multilingual construction sites in Norway. The analysis distinguishes two modes of action depiction: generic depictions, which represent the action as a general type, and contextualized depictions, which in addition include deictic references to the spatio-material environment or iconic representations of the specific manner of action performance. These two modes typically occupy different positions in the turn. Generic depictions are mostly initiated before the verbalization of the action or are synchronized with it, while contextualized depictions mostly start simultaneously with the verbalization and extend beyond the verb phrase or the turn. The pre-positioned and synchronized generic gestures are shown to serve as a practice for facilitating recognition of the verbalized action and may be temporally manipulated in order to pre-empt understanding problems in the face of reduced common linguistic resources. The post-positioned contextualized depictions serve instead to add specifying information about aspects of the action referred to and thereby to complement or supplement the meaning of the verb phrase, securing understanding of action specifics. The study contributes to research on gesture-speech synchrony by demonstrating how variation in the alignment of action depiction and syntax is used to direct the recipient’s attention toward different interactional goals.

In consecutively interpreted conversations, long multi-unit turns pose an interactional problem, as the interpreter may need to intervene into the turn space of the current speaker to interpret. This paper explores multimodal practices employed by medical professionals and interpreters to manage the temporary suspension of extended turns-in-progress. Using data from video-interpreted hospital encounters, we show how video-mediation poses challenges to the fine-tuned coordination involved in creating temporary suspension. We identify one practice used by medical professionals by which they produce turns in several chunks, or ‘installments’, temporarily suspending the ongoing turn and allowing the interpreter to begin interpreting. When a medical professional does not suspend their longer turns, the interpreter more actively signals the medical professionals, for instance through use of pre-beginning signals, to suspend the progressivity of their turn and yield for interpreting. We explore at what place during medical professionals' ongoing multi-unit turns interpreting is made relevant, how this is done and by whom.

This study explores practices employed by a person with aphasia (PWA) and his wife to organize joint planning sequences and negotiate deontic rights (a participants' entitlement to initiate planning sequences and the entitlement to accept or reject a plan). We analyze two different conversations between a man with aphasia and his wife and their adult daughter. Using Conversation Analysis (CA), we identify practices that further the PWA's participation in the interaction while planning afternoon activities together with his wife. The PWA contributes to the planning talk by initiating and modifying planning sequences. The spouse supports his participation by aligning with his initiated actions and inviting him to collaborate in planning talk she initiates. Deontic authority is shared between the conversation partners and the PWA's agency is facilitated even during disagreement. The analysis offers insight into practices that allow a PWA to use his limited communicative resources to contribute competently to planning talk.

Background Cardiovascular disease is common in kidney transplant recipients. They are considered high risk surgery candidates due to comorbidity and immunosuppression. We assessed short-term results of open-heart surgery in kidney transplant recipients and matched controls between 1989 – 2016 at our center. Methods Ninety-five patients underwent open heart surgery (48 coronary artery bypass grafting, 27 valve replacements or repairs and 29 combined procedures) after kidney transplantation. Controls (n=95) were matched for age, sex, type and year of surgery. Mean follow-up was 5.6 (4.9) years. Independent two-sample t-test and chi-square test were used to compare continuous variables and frequencies, respectively. Logistic regression was used to identify preoperative risk factors for 30-day mortality. Results Included were 76 men and 19 women; mean age 60.3 (11.1) years, 7.1 (5.6) years after transplantation. Kidney transplants had lower renal function, more hypertension, but less pulmonary hypertension than matched controls. Intraoperative data was comparable between kidney transplants and controls. Kidney transplants experienced more frequent acute kidney injury (57% versus 23%, p

Background— This article presents an update of the results achieved by modern surgery in congenital heart defects (CHDs) over the past 40 years regarding survival and the need for reoperations, especially focusing on the results from the past 2 decades. Methods and Results— From 1971 to 2011, all 7038 patients P P =0.003), and 5-year cumulative survival was 88.8% versus 95.0% ( P =0.0003). In simple versus complex defects, 434 (11.6%) versus 985 (33.8%) patients needed at least 1 reoperation before 16 years of age. In complex defects, 5-year cumulative freedom of reoperation among patients operated on in 1990 to 1999 versus 2000 to 2011 was 66% versus 73% ( P =0.0001). Conclusions— Highly significant, sequential improvements in survival and reductions in reoperations after CHD surgery were seen. A future challenge is to find methods to reduce the need for reoperations and further reduce long-term mortality.

Background Extracorporeal membrane oxygenation (ECMO) is increasingly used to save patients with severe cardiopulmonary failure at high risk of dying, but the long-term psychiatric outcome of the treatment has not been studied. Methods Twenty-eight adults who survived ECMO were subjected to psychiatric assessment 5 years after ECMO by means of interviews (MINI-Neuropsychiatric Interview and Montgomery-Asberg Depression Rating Scale) and psychometrics [Neuroticism and social conformity (EPQ-N+L); General Health Questionnaire (GHQ), Hospital Anxiety Depression Scale; Aggression Questionnaire, Toronto Alexithymia Scale, and Giessener somatic symptom checklist (GBB)]. Results Fifteen patients (54%) suffered lifetime psychiatric disorders prior to ECMO. After ECMO, 11 subjects (39%) developed new psychiatric disorders, mostly organic mental (18%), obsessive-compulsive disorders (OCD) 15%, and/or post-traumatic stress disorders (PTSD) 11%. These 11 patients reported higher scores on Montgomery-Asberg Depression Rating Scale (MADRS), GHQ, EPQ-N, and GBB. Disregarding the presence of psychiatric disorders at follow-up, ECMO patients reported high levels of distress, physical aggression, anger, and alexithymic traits. Conclusions Severe life-threatening cardiovascular or pulmonary failure with subsequent ECMO is associated with an increased prevalence of long-term psychiatric disorders and distress. Studies addressing the etiology and prevalence of psychiatric consequences after ECMO are needed.

Mediastinitis after coronary artery bypass grafting (CABG) gives a longstanding chronic inflammation and has a detrimental negative effect on long-term survival. For this reason, we aimed to study the effect of mediastinitis on graft patency after CABG. The epidemiologic design was of an exposed (mediastinitis, n = 41) versus non-exposed (non-mediastinitis, controls, n = 41) cohort with two endpoints: (i) obstruction of saphenous vein grafts (SVG) and (ii) obstruction of the internal mammary artery (IMA) grafts. The graft patency was evaluated with coronary CT-angiography examination at a median follow-up of 2·7 years. The number of occluded SVG in the mediastinitis group was 18·9% versus 15·5% in the control group. Using generalized estimating equations model with exchangeable matrix, and confounding effect of ischaemic time and patients age, we found no significant association between presence of mediastinitis and SVG obstruction [rate ratio (RR) = 0·96, 95% CI (0·52-2·67), P = 0·697]. The number of occluded IMA grafts was 10·5% in the mediastinitis group and 2·4% in the control group. Using the Poisson regression model, we estimated RR = 5·48, 95% CI (1·43-21·0) and P = 0·013. There was a significant association between mediastinitis and IMA graft obstruction, when controlling for the confounding effect of ischaemic time, body mass index, presence of diabetes mellitus and the number of diseased vessels. Presence of mediastinitis increases the risk of IMA graft obstruction. This may confirm the importance of inflammation as a major contributor to the pathogenesis of atherosclerosis and explain the negative effect of mediastinitis on a long-term survival.

Mediastinitis is treated with either vacuum-assisted closure (VAC) or traditional closed drainage (TCD) with irrigation. The aim of the study was to determine the effect of the two treatments on mortality and re-infection rate in a source population, using 21 314 consecutive patients undergoing isolated coronary artery bypass grafting (CABG) from January 1997 to October 2010. Median observation time was 2·9 years in the VAC group and 8·0 years in the TCD group. The epidemiological design was of an exposed (VAC, n = 64) versus non-exposed (TCD, n = 66) cohort with two endpoints: (1) mortality and (2) failure of sternal wound healing or re-infection. The crude effect of treatment technique versus endpoint was estimated by univariate analysis. Stratification analysis by the Mantel-Haenszel method was performed to quantify confounders and to pinpoint effect modifiers. Adjustment for confounders was performed using Cox regression analysis. Mediastinitis was diagnosed 6-105 (median 14) days after primary operation in the VAC group and 13 (5-29) days in the TCD group. There was no difference between groups in long-term survival. Failure of sternal wound healing or re-infection occurred less frequently in the VAC group (6%) than in the TCD group (21%; relative risk = 0·29, 95% CI = 0·06-0·88, P = 0·01). There are concerns for increase in right ventricle rupture in VAC compared with TCD. There was no difference in survival after VAC therapy and TCD therapy of post-CABG mediastinitis. Failure of sternal wound healing or re-infection was more common after TCD therapy.

The purpose of this study was to investigate whether global longitudinal strain measured by two-dimensional speckle tracking echocardiography could detect incipient myocardial dysfunction in patients with chronic aortic regurgitation (AR). Disclosing left ventricular (LV) dysfunction is of decisive importance for optimal timing of surgery but challenging because of the altered loading conditions.Forty-seven patients referred for aortic valve replacement because of chronic AR were studied, along with 31 healthy controls. Myocardial deformation as determined by longitudinal, circumferential, and radial strain was calculated using two-dimensional speckle-tracking echocardiography technique, in addition to LV volumes, dimensions, and ejection fraction. Strain values were normalized to end-diastolic volume to correct for the volume dependency of deformation.Global systolic longitudinal strain was significantly lower in patients with AR before surgery compared with the healthy controls (-17.5 ± 3.1% vs -22.1 ± 1.8%, P.01), while global circumferential strain and LV ejection fraction did not differ (-21.7 ± 3.4% vs -22.6 ± 2.5%, P = .22 and 59 ± 5% vs 59 ± 6%, P = .59, respectively). However, differences between patients and controls were evident for both longitudinal and circumferential strain when normalized to end-diastolic volume (-0.09 ± 0.04 vs -0.23 ± 0.08, P.01, and -0.11 ± 0.05 vs -0.24 ± 0.08, P.01, respectively). In contrast to their absolute values, both normalized variables demonstrated improvement in myocardial shortening after valve replacement (P.01).The study demonstrated reduced global longitudinal strain in patients with chronic AR with preserved LV ejection fractions. Global longitudinal strain might therefore disclose incipient myocardial dysfunction with a consequent potential for improved timing of aortic valve surgery.

Serious pulmonary failure may be treated with extracorporeal membrane oxygenation (ECMO) when other treatment has failed. The aim of this study was to analyze pre-operative risk factors of early mortality in patients who underwent either veno-arterial (VA) ECMO or veno-venous (VV) ECMO for pulmonary failure. We studied a total of 26 risk factors in 72 patients with severe pulmonary insufficiency treated with ECMO. All consecutive cases treated at our institution between Sept 1990 and Aug 2007 were included. Univariate analysis and multiple logistic regression analysis were performed on 26 risk factors. The end point was early mortality (any death within 30 days of ECMO treatment). Thirty-six (50%) of the patients died within 30 days of treatment. Age, gender, body mass index(BMI)(adults), cause of pulmonary failure, pre-ECMO treatment with nitric oxide(NO), intra-aortic balloon pump(IABP), and type of ventilation did not significantly influence early mortality. Neither pre-operative blood gas results, oxygenation index or pre-operative PaO2/FiO2ratio, nor mean ventilator days prior to ECMO gave any indications on early mortality. Liver function did not predict early mortality, but pre-ECMO serum creatinine levels were significantly lower in patients who survived. Treatment with ECMO in patients with severe pulmonary failure may save lives. It is, however, difficult to predict outcome when initiating ECMO. In this analysis, only pre-operative serum creatinine levels correlated with survival. None of the other parameters, including those which were used to select patients for ECMO treatment, could significantly predict the outcome.

Background Serious heart and pulmonary failure may be treated with extracorporeal membrane oxygenation (ECMO). The aim of this follow-up study was a multimodal assessment of outcome in children surviving ECMO at our hospital from 1991 to 2004. Methods Twenty-two children were, on average, 1.18 years old (SD = 1.92; range, 0.1 to 7.8) when ECMO was initiated. Average age at follow-up was 7.2 years (range, 1.8 to 13.9). Thirteen children were treated for cardiac and nine for pulmonary failure. Venoarterial ECMO was performed in 21 patients and venovenous ECMO in one patient. The protocol included a review of patients records, clinical, neurologic and neuropsychologic, and radiological examinations, electroencephalogram, and interviews with the parents. Results Moderate or severe impairment in at least two clinical assessments were found in 16 (72.7%) children. Five (22.7%) children had cerebral palsy and 15 (68.2%) had moderate or severe cognitive impairment. Eight (36%) children had pathological radiologic findings. Pathological electroencephalograms were found in 11 (50%) patients including four (18.2%) with epileptic activity. Children with radiologic findings had a slightly worse cognitive outcome. There was no association between the neurophysiologic findings and the neuropsycohologic performance or the radiologic findings. Based on parental assessment, only four children had pathological scores. Conclusions All children, except for two, came walking to the follow-up visit. All parents were positive to the ECMO treatment, and reported a good or slightly reduced quality of life for their child. Cerebral sequelae were frequently found in children treated with ECMO. The need for treatment and support should be assessed in order to optimize their physical and psychosocial functioning.

Background Bosnia and Herzegovina did not have invasive cardiac diagnosis or cardiac surgery before the recent war. With assistance from the United States and Norway, a cardiovascular clinic was developed. This study reports center-specific and surgeon-specific clinical outcomes. Since off-pump coronary bypass grafting surgery was prioritized in the treatment of coronary disease, a comparison was made between operations performed with and without cardiopulmonary bypass. Methods Surgeons and key staff members were trained in the United States. A Norwegian data management system for cardiac surgery was implemented and cases entered after quality review of the data. A total of 1276 patients were entered; operations were performed with cardiopulmonary bypass in 540 and without in 736. The primary surgeon was entered as a variable in an anonymous fashion. Results Overall mortality for coronary bypass grafting surgery was 1.6%, and the major complication rate was 4.5%. Patients operated on off-pump received fewer grafts and had a shorter length of stay. Unfavorable outcome was more common in patients when cardiopulmonary bypass was used in the operation. Regression analysis demonstrated that the European System for Cardiac Operative Risk Evaluation (EuroSCORE) and use of cardiopulmonary bypass were predictors of poor outcome. The individual surgeon factor did not impact on outcomes. Conclusions Our study confirms that coronary artery bypass grafting surgery may be performed safely in a poor country in a hospital without experience with cardiac surgery. Selection of talented staff and cooperation with international cardiac centers are crucial. Off-pump coronary artery bypass grafting surgery is suitable for a new center and does not require more training than standard procedures.

Background After more than a decade of experience with off-pump coronary bypass surgery, still no consensus exists concerning its benefit on clinical outcome compared to the on-pump technique. In this 12-month follow-up, we compare off-pump and on-pump surgery on the appearance of graft patency, myocardial function, and clinical outcome. Methods One hundred twenty patients were randomized to off-pump or on-pump coronary surgery. Angiography was performed intraoperatively, at 3 and 12 months. Global myocardial function was estimated by magnetic resonance imaging (MRI) preoperatively and 12 months postoperatively, as well as functional class and stress testing. Results After 12 months internal mammary artery patency was 94% in the off-pump group and 96% in the on-pump group. Vein graft patency was 80% and 87%, respectively. No statistically significant difference between the two groups existed. There were no differences in exercise capacity improvement and attenuation of symptoms between the groups. Conclusions At 12-months follow-up, off-pump coronary bypass surgery provided the same angiographic graft patency as the on-pump technique. Improvement in functional class and exercise capacity was the same in both groups.

Objective The use of aortic connector systems for proximal vein grafts in off-pump coronary artery bypass grafting might minimize aortic manipulation by eliminating the need for partial aortic clamping. The objective of this study was to asses whether use of a Symmetry connector (St Jude Medical, Inc, St Paul, Minn) reduced intraoperative cerebral embolization. Methods Thirty-two consecutive patients underwent off-pump coronary artery bypass grafting. Sixteen patients received at least one mechanical proximal vein graft anastomosis with a Symmetry aortic connector system. Sixteen patients representing the control group underwent operations with standard suturing techniques using partial aortic clamping. During surgical intervention, all patients were monitored continuously with multifrequency transcranial Doppler scanning, which detected and differentiated cerebral emboli. Results There were significantly more cerebral emboli in the Symmetry group (median, 36) compared with the control group (median, 11; P = .027). This was due to a higher number of gaseous emboli in the Symmetry group than in the control group (median, 27 vs 8; P = .014), whereas there was no significant difference regarding the number of solid emboli (median, 7 vs 3; P = .139). Conclusion Use of a Symmetry connector system during proximal vein graft anastomosis increased the number of emboli to the brain compared with a standard technique in coronary bypass surgery without cardiopulmonary bypass.

Objective The objective of this study was to investigate the patency in saphenous vein coronary bypass grafts in which the proximal anastomoses were performed with automatic connector devices or with a traditional suture technique. Methods Forty-six patients underwent coronary artery bypass grafting without cardiopulmonary bypass by using one thoracic graft and one or more saphenous vein grafts. Grafts were attached to the aorta with a Symmetry connector (St Jude Medical, Inc, St Paul, Minn) in 23 patients, and partial occlusion of the aorta and sutured anastomoses were used in 23 other patients. Grafts were studied intraoperatively with transit time flowmetry and angiography and revised if necessary. Angiography was repeated after 3 to 5 months. Results Intraoperative graft patency did not differ between the 2 groups. Follow-up angiography demonstrated excellent thoracic graft patency. Vein graft patency decreased to 50% in the Symmetry group, whereas it was 90% in the suture group ( P = .01). Twenty-five percent of the Symmetry grafts had significant stenosis in the connector. Conclusion Saphenous vein grafts anastomosed to aorta with the Symmetry proximal connector have low intermediate patency compared with those with traditionally sutured anastomoses. We do not recommend the routine use of this device in coronary artery bypass operations.

Objective Simple linear resection and endoventricular patch plasty are alternative techniques to repair postinfarction left ventricular aneurysm. The aim of the study was to compare these 2 methods with regard to early mortality and long-term survival. Methods We retrospectively reviewed 159 patients undergoing operations between 1989 and 2003. The epidemiologic design was of an exposed (simple linear repair, n=74) versus nonexposed (endoventricular patch plasty, n=85) cohort with 2 endpoints: early mortality and long-term survival. The crude effect of aneurysm repair technique versus endpoint was estimated by odds ratio, rate ratio, or relative risk and their 95% confidence intervals. Stratification analysis by using the Mantel-Haenszel method was done to quantify confounders and pinpoint effect modifiers. Adjustment for multiconfounders was performed by using logistic regression and Cox regression analysis. Survival curves were analyzed with the Breslow test and the log-rank test. Results Early mortality was 8.2% for all patients, 13.5% after linear repair and 3.5% after endoventricular patch plasty. When adjusted for multiconfounders, the risk of early mortality was significantly higher after simple linear repair than after endoventricular patch plasty (odds ratio, 4.4; 95% confidence interval, 1.1-17.8). Mean follow-up was 5.8 ± 3.8 years (range, 0-14.0 years). Overall 5-year cumulative survival was 78%, 70.1% after linear repair and 91.4% after endoventricular patch plasty. The risk of total mortality was significantly higher after linear repair than after endoventricular patch plasty when controlled for multiconfounders (relative risk, 4.5; 95% confidence interval, 2.0-9.7). Linear repair dominated early in the series and patch plasty dominated later, giving a possible learning-curve bias in favor of patch plasty that could not be adjusted for in the regression analysis. Conclusions Postinfarction left ventricular aneurysm can be repaired with satisfactory early and late results. Surgical risk was lower and long-term survival was higher after endoventricular patch plasty than simple linear repair. Differences in outcome should be interpreted with care because of the retrospective study design and the chronology of the 2 repair methods.

The aim of the study was to identify predictors for survival after repair of postinfarction left ventricular aneurysm.We retrospectively reviewed the records of 149 patients who had an operation for postinfarction left ventricular aneurysm between 1989 and 2001. The following variables were recorded: preoperative clinical, angiographic, and echocardiographic findings and operative procedures. Outcomes were early mortality (30 days) and long-term survival. Risk factors were pinpointed using t test or Mann-Whitney test, contingency tables, and survival curves. Independent risk factors were identified by logistic regression and Cox regression methods. Mean follow-up was 5.8 years (range, 0 to 13.8 years).The early mortality (30 days) rate was 8.7% altogether, and the 5-year cumulative survival rate was 77%. Advanced age, history of ventricular arrhythmia, three-vessel disease, and linear repair technique were independent risk factors for early and total mortality. Poor left ventricular function predicted reduced long-term survival but did not increase surgical risk. Survival was not affected by gender, diabetes, type and severity of symptoms, anterior or posterior aneurysm, revascularization of the left anterior descending artery, or number of distal anastomoses.Postinfarction left ventricular aneurysm can be repaired with acceptable surgical risk and long-term survival. Survival is reduced in cases with advanced age, history of ventricular arrhythmia, three-vessel disease, poor left ventricular function, and linear repair of the aneurysm.

Mediastinitis after open heart operation is an infrequent, but life-threatening complication with a reported incidence rate between 1% and 4%. Hospital mortality is estimated at 10% to 35%. The aim of the present work was to study the systemic inflammatory reaction as judged by complement activation and cytokine and chemokines release in patients with mediastinitis after open heart operation.Seven patients with clinical signs of mediastinitis were included. Three patients had undergone coronary artery bypass grafting, whereas 4 patients had combined coronary artery bypass grafting, valve replacement, or valvuloplasty. Blood samples were drawn before induction of anesthesia and at the time of reoperation, and thereafter daily during the hospital stay. Controls comprised similar patients with an uneventful postoperative course.The terminal SC5b-9 complement complex concentration in the mediastinitis patients was substantially higher compared with the controls (p0.001), and the terminal SC5b-9 complement complex values showed no overlap between the two groups. Interleukin-8, stromal cell-derived factor-1alpha and IL-6 concentrations were also significantly higher in the mediastinitis group than in the control group (p0.001), but with considerable overlap between the groups. Interleukin-1beta, interleukin-10, and monocyte chemoattractant protein-1 concentrations were slightly higher in the mediastinitis group, and no differences were seen for the tumor necrosis factor-alpha.During mediastinitis, the complement is activated and the cytokines and chemokines, interleukin-6, interleukin-8, and stromal cell-derived factor-1alpha are released. These proteins may be involved in the pathogenesis of this complication. Terminal SC5b-9 complement complex may be an indicator to discriminate mediastinitis patients from those with uneventful course.

Cardiopulmonary bypass causes a systemic inflammatory reaction, which leads to endothelial activation with increased expression of adhesion molecules. The study aim was to test whether activated endothelial cells secrete measurable amounts of soluble adhesion molecules during the time course of routine heart surgery, and whether these markers correlate with cellular activation responses. Endothelial cells from human umbilical cords were cultured by standard methods and stimulated with endotoxin. After 2 h, the expression of membrane-bound E-selectin on the cells had increased significantly ( p= 0.04), whereas soluble VCAM-1 (sVCAM-1) had increased significantly in the culture media ( p= 0.03). In agreement with these findings, sVCAM-1 increased from 399 ng/ml (median) to 581 ng/ml within 3 h postoperatively in sera from 11 patients undergoing open heart surgery ( p= 0.003). sVCAM-1, therefore, may be suitable as an early marker of endothelial activation related to the systemic inflammation after open heart surgery. The clinical significance of sVCAM-1 measurements must be further evaluated in future patient studies.

Background . Intracutaneous suture technique has been our standard method for closing sternal wounds in cardiac surgery, mainly for cosmetic reasons. However, an increased rate of postoperative infections has been reported in cosmetic surgery with this method compared with the percutanous or transcutaneous closure technique. A comparison of these two techniques in cardiac surgery is presented. Methods . In a randomized study, 300 patients were selected to intracutaneous suture (n = 150) or percutanous suture (n = 150). The endpoints were superficial and deep sternal wound infections within 6 weeks postoperatively. Results . The total infection rate was lower in the percutanous group compared with the intracutaneous group (3% versus 8%) ( p = 0.007). The superficial infection rate was lower in the percutaneous group (2.3% versus 6.7%) ( p = 0.01), whereas there was no statistically significant difference in the deep infection rate between the groups. Conclusions . The percutaneous suture technique reduces the incidence of superficial wound infections, but not the deep infection rate in open heart surgery. There was no difference in the cosmetic results on a visual scale, assessed by the patients.

(2000). Off-pump vs On-pump Surgery: A Review. Scandinavian Cardiovascular Journal: Vol. 34, No. 1, pp. 7-11.

Objective: Our objective was to study mechanisms for reduced complement activation by heparin coating of cardiopulmonary bypass equipment in clinical heart surgery. Methods: Adults undergoing elective coronary artery bypass grafting were randomized to cardiopulmonary bypass with Duraflo II heparin-coated (n = 15) or uncoated (n = 14) sets (Duraflo coating surface; Baxter International, Inc, Deerfield, Ill). Blood samples were analyzed with the use of enzyme immunoassays for C1rs-C1 inhibitor complexes and the activation products Bb, C4bc, C3bc, C5a-desArg, and the terminal complement complex. Data were compared by repeated-measures analysis of variance. Results: C1 was activated during bypass, and increases in C1rs-C1 inhibitor complexes were larger with heparin coating (P = .03). C4bc increased after administration of protamine, without intergroup differences (P = .69). Bb (P = .22) and C5a-desArg (P = .13) tended to increase less with heparin coating. Formation of C3bc (P = .03) and the terminal complement complex (P < .01) was significantly reduced with heparin coating. C5a-desArg increased 2-fold during bypass, whereas the terminal complement complex increased 10- to 20-fold. Maximal terminal complement complex concentrations were significantly correlated to maximal Bb and C3bc (R = 0.6, P < .001), but not to C1rs-C1 inhibitor complexes or C4bc (R < 0.05, P > .8). Conclusions: C1 activation during bypass was increased by heparin coating, but further classical pathway activation was held in check until administration of protamine. Heparin coating significantly inhibited C3bc and terminal complement complex formation. Terminal complement complex concentrations were related to alternative pathway activation and may be useful for evaluation of differences in bypass circuitry. Increases and intergroup differences in terminal complement complex concentrations were much larger than those in C5a-desArg. (J Thorac Cardiovasc Surg 1999;117:803-9)

Objectives: 1. To study possible clinical benefits of heparin-coated cardiopulmonary bypass in patients with a broad range of preoperative risk factors. 2. To evaluate the correlation between the terminal complement complex and clinical outcome. 3. To identify clinical predictors of complement activation and correlates of granulocyte activation during cardiac surgery. Methods: Blood samples from adults undergoing elective cardiac surgery with Duraflo II heparin-coated (n = 81) or uncoated (n = 75) cardiopulmonary bypass sets (Duraflo coating surface; Baxter International, Inc, Deerfield, Ill) were analyzed for activation of complement (C3 activation products, terminal complement complex), granulocytes (myeloperoxidase, lactoferrin), and platelets (β-thromboglobulin) by enzyme immunoassays. Preoperative risk was assessed by means of the “Higgins' score.” Complications (cardiac, renal, pulmonary, gastrointestinal, and central nervous system dysfunction, infections, death) were registered prospectively. Data were analyzed by analysis of variance, logistic regression, and linear regression. Results and conclusions: Sixty-seven percent of the patients had predefined risk factors. Complications developed in 53 patients (34%), equivalently with and without heparin-coated bypass sets (P = .44-.82), despite a significant reduction in complement and granulocyte activation by heparin coating. No clear-cut relationship between the terminal complement complex and outcome was found, even if it was significant in the models for renal and central nervous system dysfunction and infections (P = .006). The Higgins' score was significantly related to complement activation (P < .05). Approximately 50% of the variation in granulocyte activation was explained by complement (P ≤ .01) and platelet activation (P < .05), heparin/protamine dose ratio (P = .02), duration of cardiopulmonary bypass (P < .01), and gender (P < .05). Therefore measures reducing complement activation alone will not necessarily reduce granulocyte activation sufficiently for clinical significance. (J Thorac Cardiovasc Surg 1999;117:794-802)

The beneficial effects of the intraaortic balloon pump (IABP) in providing circulatory support must be weighed against its complications, particularly its vascular trauma.Five hundred nine patients who underwent open heart operations at our institution and who were treated with the IABP from January 1980 through December 1994 were studied retrospectively to assess IABP-related vascular complications and their independent preoperative predictors and the implications of IABP-related vascular complications on the patients' mortality, morbidity (clinical sepsis and organ failure), and long-term survival.Early vascular complications occurred in 56 patients (11%) and major complications occurred in 41 patients (8%). The latter consisted of aortic perforation in 1 patient, aortoiliac dissection in 2 patients, and limb ischemia in 38 patients. Logistic regression analysis identified concomitant peripheral vascular disease (p0.001), elevated preoperative end-diastolic pressure, small body surface area, and large catheter size (p0.05) as independent risk factors for IABP-related major vascular complications in patients who survived the day of operation. Late IABP-related sequelae occurred in 10 patients, 9 of whom had had early vascular complications. The presence of vascular complications per se was not a significant independent factor among other risk factors for mortality, morbidity, or long-term survival.Careful clinical assessment of the aortofemoral vascular tree is a cornerstone of early diagnosis and early intervention and usually prevents limb loss. The significant decrease in major vascular complications that has occurred over the last 5 years can be explained by the increased use of catheters with smaller diameters. The timing of IABP insertion in relation to operation and the duration of IABP use were the only device-related risk factors identified for morbidity and survival.

Postoperative organ dysfunction after cardiac operations has been related to the damaging effects of cardiopulmonary bypass (CPB). These complications are considered to be mediated partly by complement activation and subsequent activation of leucocytes due to the contact between blood and the large nonendothelial surfaces in the bypass circuit. Removal of leucocytes by filtration during the reperfusion period may potentially reduce the postoperative morbidity after CPB. Forty patients undergoing elective, primary coronary artery bypass grafting were randomized to initial identical bypass circuits until the aortic crossclamp was released. Then, the ordinary arterial line filter was closed and either a leucocyte depletion filter ( n = 20), or a control filter ( n = 20) was incorporated in the circuits during the reperfusion period of CPB. Blood samples were drawn at fixed intervals and analysed for white blood cell and platelet counts, plasma concentration of myeloperoxidase, C3-complement activation products, the terminal complement complex, and interleukins (IL)-6 and -8. The numbers of circulating white blood cells in the leucocyte-depleted group decreased during the reperfusion period from 5.5 (4.8-6.8) to 5.3 (4.4-6.2) × 109/l, and increased in the control group from 6.5 (5.1-8.0) to 7.4 (5.7-9.0) × 109/l. Two hours postoperatively the total white blood cell count in the leucocyte-depleted group was 14.7 (12.1-17.2) × 109/l, and in the control group 17.6 (14.5-20.7) × 109/l. The differences between the groups were statistical significant ( p= 0.05). There were no statistically significant differences between the groups with regard to other test parameters or clinical data. We conclude that the use of leucocyte filters during the reperfusion period in elective coronary artery bypass surgery significantly reduced the number of circulating leucocytes, whereas no effects were seen for granulocyte activation measured as myeloperoxidase release, platelet counts, complement activation, or IL-6 and -8 release. The clinical benefit of leucocyte filters in routine or high risk patients remains to be demonstrated and is suggested to be dependent on both the efficacy and the biocompatibility of the filters.

Cardiopulmonary bypass (CPB) exposes blood to large, foreign surfaces. This exposure may activate the cellular and humoral inflammatory systems, resulting in inflammatory reactions and organ dysfunction. Coating the inner surfaces of the bypass circuit may help alleviate these side-effects. The objective of this study was to determine the influence of two new surface treatments on blood cell and complement activation. Oxygenator and tubing sets coated with synthetic polymers ( n = 7) or heparin ( n = 7) were compared to uncoated sets ( n = 7) in an in vitro model of CPB. The circuits were run at 4 l/min and recirculated for 120 min. The inflammatory response was assessed at regular intervals by platelet counts, and activation of complement, leucocytes and platelets. We found that the median platelet counts decreased from 127 to 122 × 109/l (not significant, NS) in the synthetic polymer sets, from 96 to 88 × 109/l (NS) in the heparin-coated sets, and from 93 to 54 × 109/l ( p < 0.01) in the uncoated sets after 2 h of recirculation. There were significant differences in platelet counts between the coated sets and the uncoated set at end of experiments ( p < 0.05). Beta-thromboglobulin (BTG) concentrations increased in the synthetic polymer sets from 166 to 352 ng/ml ( p < 0.01), in the heparin coated sets from 336 to 1168 ng/ml ( p < 0.01), and in the uncoated sets from 301 to 3149 ng/ml ( p < 0.01) after 2 h of recirculation. The differences in BTG at termination of the experiments were significant among all three sets ( p < 0.05). Myeloperoxidase (MPO) concentrations in the synthetic polymer sets increased from 63 to 86 μg/l ( p < 0.01), in the heparin-coated sets from 90 to 208 μg/l ( p < 0.01), and in the uncoated sets from 122 to 513 μg/l ( p < 0.01) after 2 h of recirculation. The differences in MPO at termination of the experiments were significant among all three groups ( p < 0.01). There were no significant differences at termination of the experiments among the three sets regarding complement activation as measured by C3 activation products and the terminal complement complex. We conclude that in the current in vitro model of a CPB circuit, the synthetic polymer coating and the heparin coating caused significantly less platelet loss and granulocyte and platelet activation than the uncoated surface ( p < 0.05). The synthetic polymer coating caused significantly less granulocyte and platelet activation than the heparin coating ( p < 0.05). There was moderate complement activation within each group, but no significant differences among the three groups.

Background . The aim of the study was to evaluate our clinical experience with the CarboMedics Heart Valve Prosthesis. Methods . Nine hundred ninety-seven consecutive patients underwent mechanical valve implantation (aortic, 771; mitral, 169; double, 52; tricuspid, 5) with this prosthesis from September 1987 through December 1993. The mean age was 62.3 ± 13.7 years (range, 0.4 to 84 years); 56.6% (564 patients) were men. Four hundred seventy patients (47.1%) underwent additional surgical procedures. Mean follow-up was 4.1 ± 2.2 years (range, 0 to 8.3 years) with a total of 4,040 patient-years. Results . Early mortality was 5.0% (50/997; aortic, 4.4%; mitral, 6.4%; double, 9.6%). Late mortality was 14.8% (140/947). Survival at 7 years was 75.9% ± 1.8% (aortic, 78.4% ± 2%; mitral, 70.7% ± 4.5%; double, 60.8% ± 7.4%). When matched for sex and age and compared with the normal Norwegian population, our patients had an increased standard mortality ratio in both men (1.9 ± 0.4) and women (2.9 ± 0.6). The linearized rate of major thromboembolism was 0.9% per patient-year, valve thrombosis 0.2% per patient-year, major bleeding event 0.6% per patient-year, paravalvular leak needing reoperation 0.5% per patient-year, prosthetic valve endocarditis 0.1% per patient-year, and of all reoperations 0.6% per patient-year. Conclusions . The CarboMedics Heart Valve Prosthesis has incidences of morbid events comparable with or better than reported for other mechanical valves.

The intraaortic balloon pump (IABP) is the primary mechanical device used for perioperative cardiac failure.We analyzed the prognostic predictors and long-term survival of 344 patients undergoing cardiac operations who required the perioperative use of an IABP at our institution from January 1980 to December 1989. Hospital survivors (163 patients) were followed up for a mean of 7.45 years (range, 1 month to 15.3 years); cumulative follow-up included 1,167 patient-years.The early mortality rate was 52.6% (181 patients). From parameters available at the time of IABP insertion, logistic regression analysis identified preoperative serum creatinine level, left ventricular ejection fraction, perioperative myocardial infarction, timing of IABP insertion, and indication for operation as independent predictors of early (30-day) death (p0.05). Cox regression analysis of hospital survivors identified timing of IABP insertion, perfusion time, and preoperative serum creatinine level as independent prognostic factors for late death (p0.05), whereas patient age was only marginally significant (p0.06). There was no association between IABP-related complications and death. Survival analysis demonstrated a 10-year actual survival rate of 22.04% +/- 0.023%, with 57 patients still at risk and significantly improved survival among those who received an IABP before operation (p0.02).The early mortality rate in patients who received an IABP was high. Hospital survivors had a relatively good long-term prognosis. The significantly better short- and long-term survival of patients who received an IABP before operation may justify more liberal preoperative use of the IABP in high-risk patients.

We describe a delayed, life-threatening complication in a boy operated on using the Nuss-procedure 2 months earlier. On admittance he was in shock with cardiac tamponade. An immediate needle aspiration of blood from the pericardium was done before a median sternotomy. The Nuss-bar was removed, and we identified a 1.5-cm laceration in the adventitial layer of the ascending aorta as the source of bleeding. The tear was closed, and the patient had an uneventful recovery. Careful positioning of the bar is necessary to avoid complications. Measures must be taken postoperatively to confirm that the steel bar does not rotate.

Intraoperative angiography in minimally invasive direct coronary artery bypass grafting without cardiopulmonary bypass and in hybrid procedures is reported. Twelve procedures were performed in a specially designed surgical-radiologic suite with a cross-disciplinary organization. In 2 patients the anastomosis was successfully revised on the basis of angiographic findings. In 4 of the 12 patients anastomosis of the left internal mammary artery to the left anterior descending coronary artery performed as a minimally invasive direct coronary artery bypass grafting procedure was combined with percutaneous transluminal coronary angioplasty of lesions in other coronary vessels in the same session. Intraoperative angiography allows a reliable diagnosis of an anastomosis or graft failure and prompt and reliable correction, and it allows the combination of minimally invasive direct coronary artery bypass grafting and angioplasty in one session.

Background and Purpose We sought to determine the number of cerebral microembolic signals (MES) and their time of occurrence during the two most frequent types of cardiopulmonary bypass (CPB) surgery: coronary artery bypass grafting (CABG) and cardiac valve replacement (VR). Furthermore, we sought to examine the association between MES, patient characteristics, and intraoperative parameters. Methods Forty-two patients were studied, 15 of whom had CABG and 27 VR. Cerebral MES were detected with the use of transcranial Doppler monitoring of the right middle cerebral artery. Results Cerebral MES were detected in all patients. The number was significantly higher during VR (median, 1048) than during CABG (median, 82) ( P P Conclusions A significantly higher number of cerebral MES were detected during VR than during CABG. The highest number occurred in VR patients when effective heart ejection was regained and in CABG patients when the aorta was cross-clamped and on release of the side clamp. The total number of MES increased at lower nasopharyngeal temperatures. Transcranial Doppler monitoring may alert the surgical team when emboli enter the cerebral circulation during CPB surgery, thus allowing preventive measures to be taken.

To evaluate whether the application of heparin treated circuits for elective coronary artery surgery improves postoperative recovery, a European multicenter randomised clinical trial was carried out.In 11 European heart centers, 805 low-risk patients underwent cardiopulmonary bypass (CPB) with either an untreated circuit (n = 407) or an identical but heparin treated circuit (n = 398, Duraflo II).Significant differences were found among participating centers with respect to patient characteristics, blood handling procedures and postoperative care. The use of heparin treated circuits revealed no overall changes in blood loss, blood use, time on ventilator, occurrence of adverse events, morbidity, mortality, and intensive care stay. These results did not change after adjustment for centers and (other) prognostic factors as analysed with logistic regression. In both groups no clinical or technical (patient or device related) side effects were reported. Because female gender and aortic cross clamp time appeared as prognostic factors in the logistic regression analysis, a subgroup analysis with these variables was performed. In a subpopulation of females (n = 99), those receiving heparin treated circuits needed less blood products, had a lower incidence of rhythm disturbances and were extubated earlier than controls. In another subgroup of patients with aortic cross clamp time exceeding 60 min (n = 197), the amount of patients requiring prolonged intensive care treatment (24 h) was significantly lower when they received heparin treated circuits versus controls.These findings suggest that improved recovery can be expected with heparin treated circuits in specific higher risk patient populations (e.g. females) and when prolonged aortic cross clamp time is anticipated. Further investigations are recommended to analyses the clinical benefit of heparin treated circuits in studies with patients in different well defined risk categories and under better standardised circumstances.

Objecti6e: This study was carried out to: (a) compare complement and granulocyte activation during cardiac operations in patients operated with cardiopulmonary bypass coated with heparin by the Duraflo II method, with activation in patients operated with uncoated circuits; and (b) relate complement, and granulocyte activation to selected adverse effects. Methods: In a multicentre study among Rikshospitalet, Ullevaal Hospital in Norway and Uppsala University Hospital in Sweden, plasma concentrations of the complement activation products C4b:iC4b:C4c (C4bc), C3b:iC3b:C3c (C3bc), the terminal SC5b-9 complement complex (TCC), and the granulocyte proteins myeloperoxidase and lactoferrin were assessed in two groups of patients undergoing aortocoronary bypass. Seventy-six patients underwent surgery operated with circuits coated by the Duraflo II heparin coating and 75 with uncoated circuits. The same amount of systemic heparin was administered to all patients. Results: In both groups a significant increase in C4bc was first seen by the end of operation, from 86.79 12.5 to 273.09 277.4 nM in controls and from 86.9918.5 to 320.29190.5 nM in the control group, confirming previous documentation that the classical pathway is not activated during CPB, but as a consequence of protamin administration. The formation of C4bc did not differ significantly between the two groups. In the uncoated group the C3bc concentration increased from 124.09 15.3 to a maximum of 1176.1964.7 nM (PB0.01) and in the coated group it increased from 129.89 16.1 to a maximum of 1019.49 54.9 nM (PB0.01) during CPB. Summary values but not peak values differed significantly between the groups. In the uncoated group the TCC concentration increased from 0.5290.03 to a maximum value of 8.099 0.57 AU:ml (PB 0.01) while in the coated group the TCC concentration increased from a baseline of 0.539 0.03 to a peak value of 5.29 0.24. AU:ml (PB 0.01). The difference between the peak values was statistically significant (P 0.00002). In both groups a significant increase in myeloperoxidase and lactoferrin release was observed by the end of operation. There was no difference in myeloperoxidase or lactoferrin release between the two groups. TCC levels were compared to the occurrence of perioperative infarction, development of lung or renal failure, postoperative bleeding, time on ventilator and days in hospital. Three patients developed perioperative infarction; the peak levels of TCC were significantly higher in these patients than in the 148 patients that did not develop infarction. The reduction in TCC formation in the heparin-coated group was not associated with differences in any of the other clinical parameters. Few adverse effects occurred in the study. The peak values of C3bc were higher in the patients needing inotropic support than in those

Isolated aortic (AVR, N = 71), mitral (MVR, N = 103), tricuspid (TVR, N = 3), pulmonary (PVR, N = 8), combined AVR + MVR (N = 4), or combined MVR + TVR (N = 2) valve replacement with a Carpentier-Edwards porcine bioprosthesis was performed in 191 patients between 1979 and 1986. Mean age was 56.9 +/- 17 (range 5-80) years in the total cohort. The operative mortality rates were 5.6% and 8.7%, respectively, for AVR and MVR. Mean observation time was 8 +/- 4.2 (0-16.7) years (total = 1.467 patient-years). Follow-up was 100% complete with respect to mortality. There were 78 late deaths (44%). Actuarial survival rates at 5 and 10 years were 73.2 +/- 5.2 and 52.1 +/- 6.6 for AVR and 76.7 +/- 4.2 and 61.6 +/- 4.8 for MVR. Coronary artery disease, concomitant coronary artery bypass grafting and emergency operation were significant risk factors of early mortality (p0.05). Postoperatively, sepsis and multiorgan failure were associated with early mortality (p0.05). The 10-year actuarial freedom from structural deterioration for AVR was 89 +/- 4.6 and 76.4 +/- 4.3 for MVR. It is concluded that structural valve failure is the most important factor that adversely affects the performance of Carpentier-Edwards bioprosthesis.

In an in vitro study, extracorporeal circuits equipped with either a leukocyte-depleting filter (n = 5) or a standard arterial-line filter (n = 5) were perfused for 120 minutes with fresh human whole blood. Leukocyte activation, leukocyte and platelet counts and complement activation were studied. Significant reduction of leukocyte and platelet counts and significant activation of leukocytes and of platelets were found in both groups, but without significant intergroup difference for any parameter after 120 minutes of perfusion. The leukocyte-depleting filters, however, were somewhat more effective in removing leukocytes during the initial 30 minutes of circulation.

Forty patients undergoing CPB for coronary artery surgery, using a standardized technical setting, were randomized to receive either Ringer's acetate, dextran 70 (Macrodex), polygeline (Haemaccel) or albumin 4% for volume replacement during and after surgery. The choice of fluid did not affect early complement activation (C3 activation products). Higher values of the terminal complement complex (TCC) were found only at the end of the operation in patients receiving polygeline. There were no differences between any two of the four groups during the postoperative course. The use of blood transfusion or autotransfusion and the degree of haemodilution and hypothermia did not affect complement activation. We conclude that complement activation in association with open-heart surgery is only marginally affected by the choice of fluid for volume replacement.

Complete surgical closure of coronary artery fistulas may be difficult because of complex anatomy and often multiple sites of origin. This study therefore assessed whether intraoperative fistula imaging would contribute to and improve the final surgical result. Seven adult patients underwent operation for coronary arteriovenous fistula during a 10-year period. In all 4 patients who had image guidance, the operation was guided by immediate imaging to achieve complete and persistent closure. In contrast, 2 of 3 patients who underwent operation without image guidance had residual left-to-right shunts at follow-up. Image guidance was helpful and increased the success rate of surgical closure of coronary artery fistulas.

Background. This study examined the midterm results with the CarboMedics prosthetic valve. Methods. From 1987 through 1991 a total of 569 patients received the CarboMedics prosthesis. Results. Early mortality was 4.9% and related to emergency operation, presence of diabetes mellitus, coronary artery disease, preoperative New York Heart Association class, duration of cardiopulmonary bypass, and aortic cross-clamp time. Midterm follow-up with respect to mortality was 100% complete. All patients were followed up in the hospital after 1 year. In addition 86% of the patients responded to a questionnaire. Mean follow-up was 3 years (range, 0 to 5.6 years). Cumulative survival at 1 and 4 years was 91.2% ± 1.2% and 83.7% ± 1.8%, respectively. Five patients experienced obstructive valve thrombosis (0.3%/patient-year), 16 patients had major thromboembolic events (0.9%/patient-year), and 10 patients had major warfarin-related bleeding (0.6%/patient-year) requiring hospitalization or blood transfusions. Eight patients were reoperated on for paraprosthetic leak (0.4%/patient-year). Prosthetic valve endocarditis developed in 4 patients (0.2%/patient-year). No structural valve failure was observed. Conclusions. Midterm follow-up demonstrates that the CarboMedics mechanical prosthesis is reliable and has an acceptable rate of valve-related complications.

The effects on fluid balance, pulmonary tunctions and economics were evaluated in a randomized comparison of one colloid free and three colloid containing fluid regimens, for 48 hours during and after coronary artery-bypass (CAB) surgery. A standard regimen for anaesthesia, extracorporeal circulation and monitoring was used. Only Ringer's acetate (RAc) was used as priming solution for extracorporeal circulation. Forty patients were randomized to receive either RAc, polygeline 35 mg-ml-1 (Haemaccel®), dextran 70 (Macrodex®) 60 mg ml-14, or albumin 40 mg-ml-1 in saline whenever fluid volume was needed to stabilize haemodynamics. At the end of the operation, fluid retention was significantly lower in patients receiving polygeline and dextran 70, compared with patients receiving RAc. At 48 hours, however, there were no differences in cumulative fluid balance. Patients in the colloid groups postoperatively had a higher serum colloid osmotic pressure (s-COP), bui a higher net lung capillary filtration pressure (AP) only on the second postoperative day than the RAc group. However, this did not adversely atfect intrapulmonary venous admixture, arterial oxygen tension, or time on respirator in the RAc group compared with the colloid groups. The most expensive colloid fluid regimen (albumin) cost about 230 USS more per patient than the RAc fluid regimen. We conclude that Ringer's acetate for volume replacement to stabilize haemodynamics during and after CAB surgery is associated with increased fluid retention only during the intraoperative period, compared with dextran 70 or polygeline, and with a lower serum colloid osmotic pressure and net lung capillary filtration pressure postoperatively, compared with all three colloid groups. This does not affect pulmonary functions adversely. Thus, the RAc regimen is clinically fully acceptable and economically more favourable than the polygeline, dextran 70, and albumin-containing fluid regimens.

The degree of complement activation during cardiopulmonary bypass is considered a valuable parameter of biocompatibility of the extracorporeal circuit. In an in vitro setting with a heart-lung machine primed with fresh whole blood and saline solution, the C3 activation products C3b, iC3b, and C3c and the terminal complement complex were measured in double-antibody enzyme immunosorbent assays. No differences were found between seven sets treated with Duraflo II heparin coating and seven uncoated sets after 2 hours of circulation. C3 activation products (expressed as median and 95% confidence intervals) increased from 4.5 AU (2.8 to 12.3 AU) to 16.5 AU (10.0 to 19.4 AU) in the uncoated sets (p = 0.02) and from 4.6 AU (2.2 to 5.8 AU) to 19.3 AU (3.5 to 27.1 AU) in the coated sets (p = 0.02). Terminal complement complex increased from 5.7 AU (2.7 to 11.3 AU) to 13.6 AU (8.2 to 17.8 AU) in the uncoated sets (p = 0.02) and from 7.9 AU (4.6 to 11.4 AU) to 17.3 AU (9.4 to 35.1 AU) in the coated sets (p = 0.02). A significant drop in thrombocyte levels was observed in both coated and uncoated sets. In a supplementary series, the sterilization process did not influence the results. Although Duraflo II heparin coating is considered highly effective in preventing coagulation, it did not prevent complement activation in the present in vitro study. We hypothesize that the mode by which the heparin molecule is bound to the surface may be essential to obtain effects on both coagulation and complement system.

Sixty-three patients admitted for routine coronary bypass operations were randomized to cardiopulmonary bypass (CPB) with a membrane oxygenator (Capiox- CA) or a bubbler (Polystan or William Harvey- WH), and in the Polystan group to prime with or without albumin (P+ or P-). Platelets were counted and blood loss from the mediastinal drains during the first 12 postoperative hours was measured. The reduction in platelet numbers from baseline to closure of the sternum was significantly larger in the P- group (121 x 109/l, median) than in the CA group (55 x 109/l) (p 9/l) and WH (90 x 109/l) groups. The reduced platelet loss in the P+ group compared with P- was accompanied by a significant reduction in early postoperative chest tube drainage (480 versus 728 ml). Thus, precirculation of the CPB circuit with prime containing a low dose of albumin was a simple and inexpensive means of increasing platelet function with a bubble oxygenator.

Complement activation after cardiopulmonary bypass is correlated with postoperative organ dysfunction. Heparin coating of the entire blood-contact surface of the cardiopulmonary bypass circuit has proved to reduce complement activation in vitro. A membrane oxygenator and tubing setup coated with functionally active heparin was compared with an uncoated, otherwise identical setup in 20 patients undergoing routine coronary bypass operations. The concentrations of C3 activation products and the terminal complement complex were measured in sensitive and specific enzyme immunoassays. Peak concentrations of C3 activation products were 90.1 (74.7 to 107.4) AU/ml (medians and 95% confidence intervals) and 52.4 (35.7 to 76.4) AU/ml with the uncoated and coated setups, respectively (p = 0.02). The corresponding concentrations of the terminal complement complex were 26.2 (20.1 to 37.5) AU/ml and 13.7 (11.1 to 25.1) AU/ml (p = 0.03). Blood loss from the mediastinal drains during the first 12 postoperative hours was 533 (416 to 975) ml in patients treated with the uncoated setup and 388 (313 to 579) ml in the coated treatment group (p = 0.06) and was significantly correlated with peak concentrations of the terminal complement complex (p = 0.01). There were no differences in neutrophil counts nor platelet numbers between the treatment groups. The approximate 45% reduction in complement activation with the heparin-coated cardiopulmonary bypass device indicates a substantial improvement of biocompatibility. (J T horac C ardiovasc S urg 1992;103:806-13)

In the 18 months up to July 1983, 120 Björk-Shiley convexo-concave prostheses with 70 degrees opening angle were implanted in 47 women and 61 men aged 19-78 (mean 58.6) years. The prosthetic valves were aortic in 65 cases, mitral in 23 and both aortic and mitral in 20 cases. Emergency operation was required in ten cases, and concomitant surgery was performed in 43 (39.8%). The early mortality was 5.5%. A follow-up study, comprising 498 patient years, revealed 73.1% 5-year survival. There were three mechanical failures of prosthesis, in one of which re-replacement was successful. Elective prosthesis replacement was performed in four other cases judged to be at high risk of strut fracture.