A Matched-Paired Comparative Analysis of the Hemodynamics of the Trifecta and Perimount Aortic Bioprostheses.

BACKGROUND AND AIM OF THE STUDY: Current cohort studies comparing the Trifecta valve to alternative pericardial bioprostheses are limited by selection bias. The study aim was to determine if hemodynamics are improved after the aortic valve implantation of a Trifecta valve as compared to a standard pericardial valve, when evaluated using strict paired matching for specific key relevant confounders. METHODS: Valve hemodynamics were compared in patients undergoing implantation with a Trifecta or Perimount valve matched for left ventricular outflow tract (LVOT) diameter, gender, age, body size, and days since surgery, using a 1:1 matched-paired cohort analysis (n = 20 per group). RESULTS: Patients receiving a Trifecta valve had a larger increase in indexed stroke volume (SVi) relative to baseline compared to the Perimount patients (p = 0.013), in whom SVi was decreased. The mean transvalvular pressure gradient was lower in Trifecta patients despite the larger SVi (p = 0.02). The effective orifice area (EOA) and indexed EOA (EOAi) were significantly larger in Trifecta patients compared to Perimount patients (2.04 +/- 0.46 versus 1.77 +/- 0.45 cm2, p = 0.049; 1.10 +/- 0.22 versus 0.95 +/- 0.06 cm2/m2, p = 0.027, respectively), and there was a greater increase in EOA and EOAi from baseline (p = 0.010 for both). Severe prosthesis-patient mismatch (PPM) (EOAi < or = 0.65 cm2/m2) was seen in two (10%) of the Perimount cases, but in none of the patients with the Trifecta valve (p = 0.072). CONCLUSION: Trifecta valve implantation is associated with a significant improvement in EOA and a decreased incidence of PPM as compared to the Perimount valve. The superior hemodynamic outcomes observed support consideration of this valve for aortic valve replacement, particularly in patients with a small LVOT at risk for PPM.

Deep hypothermic circulatory arrest: alternative strategies for cerebral perfusion. A review article.

Deep hypothermic circulatory arrest is an essential tool in the surgeon's armamentarium. There are essentially three strategies to address cerebral ischemia during arrest periods. Early surgical case series pioneered the option of complete anoxia with deep hypothermia. Subsequent innovators introduced the concept of retrograde perfusion of the cerebral vessels through the venous system, and others have advocated the use of selective and non-selective antegrade perfusion of the cerebral arteries. Clinical studies assessing outcomes of the three approaches are compromised by small patient numbers, retrospective design and surgeon bias. In this review, the authors will briefly discuss the conceptual basis of these strategies and the literature comparing these approaches in terms of key neurologic outcomes. The importance of this topic will emphasize the key role the perfusion community plays in establishing guidelines for best practice in circulatory arrest to go forward with education and research in this area.

Temperature management and monitoring practices during adult cardiac surgery under cardiopulmonary bypass: results of a Canadian national survey.

BACKGROUND: Mild to moderate systemic hypothermia is commonly used as a cerebral protective strategy during adult cardiac surgery. The benefits of this strategy for routine cardiac surgery have been questioned and the adverse effects of hyperthermia demonstrated. The purpose of the present study was to examine current temperature management and monitoring practices during adult cardiac surgery using CPB in Canada. METHODS: Web-based survey referring to adult cases undergoing cardiac surgery using CPB without the use of deep hypothermic circulatory arrest. Thirty-two questionnaires were completed, representing a 100% response rate. RESULTS: The usual management is to cool patients during CPB at 30 (94%) centers for low-risk (isolated primary CABG) cases and at 31 (97%) centers for high-risk (all other) cases. The average nadir temperature at the target site achieved on CPB is 34°C (range 28°C - 36°C). At 26 (81%) centers, patients are typically rewarmed to a target temperature between 36°C and 37°C before separation from CPB. Only 6 (19%) centers reported that thermistors and coupled devices used to monitor blood temperature are checked for accuracy or calibrated according to the product operating directive's schedule or more often. CONCLUSIONS: Contemporary management of adult cardiac surgery under CPB still involves induction of mild to moderate systemic hypothermia. Significant practice variation exists across the country with respect to target temperatures for cooling and rewarming, as well as the site for temperature monitoring. This probably reflects the lack of definitive evidence. There is a need for well-conducted clinical trials to provide more robust evidence regarding temperature management.

A decision aid for autologous pre-donation in cardiac surgery--a randomized trial.

OBJECTIVES: The objective of this randomized, controlled study was to determine the usefulness of a decision aid on pre-donation of autologous blood before elective open heart surgery. METHODS: The decision aid (DA) group received a tape and booklet which described the options for peri-operative transfusion in detail. The no decision aid (NDA) group received information usually given to patients about autologous donation. RESULTS: A total of 120 patients were randomized. The DA group rated themselves better prepared for decision making and showed significant improvements in knowledge (p = 0.001) and realistic risk perceptions (p = 0.001). In both groups there was an increase in the proportion of patients choosing allogeneic blood between baseline and follow-up (p = 0.001). Patients in the DA group were significantly more satisfied with the amount of information they received, how they were treated and with the decision they made, than patients in the NDA group. CONCLUSION: The decision aid is useful in preparing patients for decision making. PRACTICE IMPLICATIONS: The next stage is to explore strategies to make it available to all appropriate patients.

Assessment of the Impact of Skeletonization on Pleuropulmonary Changes after Bilateral Internal Thoracic Artery Harvest for Coronary Artery Bypass Grafting.

BACKGROUND AND AIMS: Skeletonization has been proposed as a technique to minimize the risk of sternal devascularization during bilateral internal thoracic artery harvest for coronary artery bypass grafting. The impact of this strategy on late radiologic pleuropulmonary changes has not been addressed. MATERIAL AND METHODS: Post-operative chest radiographs from patients (n = 253 per group) undergoing bilateral internal thoracic artery harvest using skeletonized and non-skeletonized techniques were reviewed by blinded radiologists. The primary outcome was the incidence of atelectasis and pleural effusion. Multivariable linear regression models were derived to assess the relationship of radiologic pleuropulmonary outcomes to patients and operative variables. RESULTS AND CONCLUSION: Patients in the skeletonized group were older (p < 0.0001), had a lower preoperative hematocrit (p = 0.014), had higher prevalence of peripheral vascular disease (p = 0.001), were of female gender (p = 0.015), underwent off-pump surgery (p < 0.001), had urgent/emergent status (p = 0.024), and had chronic obstructive pulmonary disease (p = 0.019). There was no difference in the incidence of post-operative complications, ventilation time, or intensive care unit stay. There was no difference in the severity of post-operative atelectasis in both groups. More patients in the non-skeletonized group had a grade 2/3 left pleural effusion on the late post-operative chest X-ray (p = 0.007). The independent effect of skeletonization on the development of a late left pleural effusion was significant (odds ratio = 0.558, 95% confidence interval = 0.359-0.866, p = 0.009). Skeletonization results in a decreased incidence of late post-operative left pleural effusion with no difference in early or late atelectasis. Further studies are warranted to assess the mechanism of these pleuropulmonary changes and the impact of other factors such as pleural violation during surgery.

The effect of antithrombin III-independent thrombin inhibitors and heparin on fibrin accretion onto fibrin-coated polyethylene.

Prosthetic vascular grafts become coated with a layer of fibrin that contributes to graft thrombosis and occlusion. We compared the effect of antithrombin III-independent inhibitors of thrombin with heparin for their ability to prevent fibrin accretion onto a model of a vascular graft formed in vitro by coating polyethylene tubing with thrombin bound to a layer of polymerized fibrin. Equivalent antithrombin concentrations of heparin, D-Phe-Pro-Arg CH2Cl (PPACK), recombinant hirudin (r-hirudin), and Hirulog-1 were added to barium chloride-absorbed plasma containing radiolabelled fibrinogen. Whereas, PPACK and r-hirudin persistently inhibited fibrin accretion, the inhibition by heparin was transient. Hirulog-1 had no effect on early fibrin accretion and was actually associated with enhanced accretion at 30 min (control 11.7 +/- 2.0 micrograms fibrin/cm2; Hirulog-1, 18.4 +/- 3.5 micrograms fibrin/cm2, p < 0.001). Both Hirulog-1 and r-hirudin displaced radiolabelled thrombin from the fibrin surface. Whereas hirudin-thrombin complexes are stable, Hirulog-1 produces only transient inhibition of the displaced thrombin thereby accounting for the enhanced fibrin accretion with this anticoagulant. These studies show that the antithrombin III-independent inhibitors, r-hirudin and PPACK, are more effective inhibitors of fibrin accretion onto fibrin-coated polyethylene than heparin or Hirulog-1. In addition, they emphasize the importance of determining the ability of anticoagulants to displace thrombin from fibrin and to form stable thrombin-inhibitor complexes; lack of stability of thrombin-inhibitor complexes must be countered by levels of anticoagulant that are adequate to maintain its effectiveness.

Displacement of fibrin-bound thrombin by r-hirudin precludes the use of 131I-r-hirudin for detecting pulmonary emboli in the rabbit.

Pulmonary emboli are detectable by filling defects in the pulmonary vasculature upon pulmonary angiography. Emboli derived from venous thrombi are rich in fibrin to which thrombin remains bound. Hirudin, a specific thrombin inhibitor, binds to thrombin to yield a 1:1 stoichiometric complex. We examined whether 131I-recombinant hirudin (r-hirudin) could be used to detect pulmonary emboli in rabbits. Clots were formed by re-calcifying rabbit plasma in vitro, and then injected (0.034 ml) into a femoral vein to lodge in the lungs. 131I-r-hirudin (29 +/- 4 microCi/kg) was injected intravenously but emboli could not be detected by gamma camera in real time. Post-mortem analysis of lung tissue showed that 131I-r-hirudin did not associate with emboli prepared with 125I-fibrin. Because of these findings, we used different techniques to look at the binding of hirudin to plasma clots. Clots formed in vitro were incubated with 131I-r-hirudin in the presence of equimolar amounts of 125I-albumin; specific binding of 131I-r-hirudin was not observed. Experiments with immobilized fibrin(ogen) showed that 125I-r-hirudin did not bind to and remain with fibrin-bound 131I-thrombin but did lead to the inactivation and displacement of up to 70% of bound thrombin as r-hirudin-thrombin complex; residual thrombin bound to fibrin remained active. Thus, released r-hirudin-thrombin complex is probably cleared rapidly from the region of the embolus in vivo; radioiodinated r-hirudin may not, therefore, be useful as a marker for detecting emboli.

Platelet accumulation on fibrin-coated polyethylene: role of platelet activation and factor XIII.

Platelet accumulation on small- and medium-calibre vascular grafts plays a significant role in graft occlusion. We examined platelet accumulation on the surface of fibrin-coated polyethylene tubing (internal diameter 0.17 cm) during 10 min flow (10 ml/min) at high wall shear rate (764 s-1). Washed platelets labelled with 51Cr were resuspended in Tyrode solution containing albumin, apyrase and red blood cells (hematocrit 40%). When the thrombin that was used to form the fibrin-coated surface was inactivated with FPRCH2Cl before perfusion of the tubes with the platelet: red blood cell suspension, the accumulation of platelets was 59,840 +/- 27,960 platelets per mm2, whereas accumulation on fibrin with residual active thrombin was 316,750 +/- 32,560 platelets per mm2 (n = 4). When the fibrin on the surface was cross-linked by including recombinant factor XIII (rFXIII) in the fibrinogen solution used to prepare the fibrin-coated surface, platelet accumulation, after thrombin neutralization, was reduced by the cross-linking from 46,974 +/- 9702 to 36,818 +/- 7964 platelets per mm2 (n = 12, p < 0.01). Platelet accumulation on tubes coated with D-dimer was ten times less than on tubes coated with D-domain; this finding also supports the observation that cross-linking of fibrin with the formation gamma-gamma dimers reduces platelet accumulation on the fibrin-coated surface. Thrombin-activated platelets themselves were shown to cross-link fibrin when they had adhered to it during perfusion, or in a static system in which thrombin was used to form clots from FXIII-free fibrinogen in the presence of platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Patterns of failure in Hancock pericardial bioprostheses.

A series of Hancock pericardial valve bioprostheses was reviewed for cases of primary valve failure. Thirteen mitral and 10 aortic valve explants were recovered from 21 adult patients. Mitral valves had been in place for a mean of 56.4 months, and aortic valves for 53.8 months. All valves failed with cusp tears from stents (with a mean of 1.7 for mitral valves and 2.6 for aortic valves) in a predictable pattern, suggesting that wear and stress at cusp stitch sites are important in their pathogenesis. The topography of these tears is illustrated as are the less common associates of primary failure, such as calcification, fibrosis, and thrombosis. Similarities and differences of this valve's failure compared with that of the Ionescu-Shiley pericardial valve are discussed.

Platelet-rich plasmapheresis in cardiac surgery: a meta-analysis of the effect on transfusion requirements.

OBJECTIVE: Our purpose was to determine whether intraoperative platelet-rich plasmapheresis in cardiac surgery is effective in reducing the proportion of patients exposed to allogeneic red cell transfusions. METHODS: A systematic search for prospective, randomized trials of platelet-rich plasmapheresis in cardiac surgery, using MEDLINE, HEALTHSTAR, Current Contents, "Biological Abstracts," and EMBASE/Excerpta Medica up to August 1997, was completed. Trials were included if they reported either the proportion of patients exposed to allogeneic red cells or the units of allogeneic red cells transfused. Trials were abstracted by 2 independent investigators and the quality of trial design was assessed with the use of a validated scale. RESULTS: Seventeen references met the inclusion criteria (1369 patients [675 control: 694 platelet-rich plasmapheresis]). Platelet-rich plasmapheresis reduced the likelihood of exposure to allogeneic red cells in cardiac surgery (odds ratio 0.44; 95% confidence interval 0.27, 0.72, P = .001). Platelet-rich plasmapheresis had a small but statistically significant effect on both the volume of blood lost in the first 24 hours (weighted mean difference -102 mL; 95% confidence interval -148, -55 mL, P < .0001) and the mean units transfused (weighted mean difference -0.33 units; 95% confidence interval -0.43, -0.23, P < .0001). However, platelet-rich plasmapheresis was only marginally effective (odds ratio 0.83, 95% confidence interval 0.34, 2.01, P = .68) for "good" quality trials, whereas it appeared very effective in trials with poor methodologic quality (odds ratio 0.33, 95% confidence interval 0.17, 0.62, P = .0007). CONCLUSIONS: Although platelet-rich plasmapheresis appeared effective in decreasing the proportion of patients receiving transfusions after cardiac operations, the quality of most of the supporting trials was low and the benefit was small in trials of good quality. Further clinical trials should be completed.

Use of recombinant-hirudin in pulmonary thromboendarterectomy.

A patient with chronic thromboembolic pulmonary hypertension and heparin-induced thrombocytopenia successfully underwent pulmonary thromboendarterectomy with circulatory arrest, using recombinant hirudin as an alternative anticoagulant to heparin. Techniques for administration as well as monitoring of this drug's effects are discussed.

Is tranexamic acid safe in patients undergoing coronary endarterectomy?

BACKGROUND: Patients undergoing coronary endarterectomy during coronary artery bypass grafting (CABG) are at increased risk of perioperative myocardial infarction due to coronary intimal disruption. Data assessing the safety of the antifibrinolytic drug tranexamic acid (TA) in patients undergoing this procedure are lacking. METHODS: From September 1997 to December 1999, 221 patients underwent nonemergency primary CABG with endarterectomy of the right coronary artery alone in 149, the left anterior descending in 35, or both right and left anterior descending in 27. TA was administered intraoperatively to 87 patients (TA group: average total dose 62 +/- 4.4 mg/kg; range 20 to 109 mg/kg), and was not administered to 134 patients (No TA group). RESULTS: The patient characteristics of the 2 groups were similar. In-hospital mortality consisted of 2 patients in the TA group and 4 patients in the No TA group. Perioperative myocardial infarction rates were 2% and 5% in the TA and No TA groups, respectively (p = 0.49). The relative risk for any type of perioperative cardiac ischemic event in the TA group versus the No TA group was 0.77 (95% CI; 0.4, 1.2). Patients in the TA group had a significant reduction in postoperative chest tube drainage (685 versus 894 mL in the TA versus No TA groups, respectively) and in the use of fresh-frozen plasma (p = 0.03). CONCLUSIONS: These results suggest that the clinical effectiveness of tranexamic acid in reducing postoperative blood loss in patients undergoing coronary endarterectomy is not associated with a higher incidence of myocardial ischemia-related complications.

Hematologic evaluation of cardiopulmonary bypass circuits prepared with a novel block copolymer.

BACKGROUND: To decrease the complications associated with cardiopulmonary bypass, novel biomaterials have been introduced that may be less thrombogenic than standard synthetic surfaces. METHODS: Thirty-four patients undergoing coronary artery bypass grafting were randomized to bypass using either a control circuit or a circuit prepared "tip-to-tip" with a triblock-copolymer (polycaprolactone-polydimethylsiloxane-polycaprolactone). RESULTS: There was a progressive increase in thrombin generation in the control group during bypass, which was not seen in the test group. The test surface decreased the release of tissue plasminogen activator and plasmin-alpha2-antiplasmin complex formation (p<0.005). There was also an increased platelet count and a decreased platelet activation in the test group, as detected by GMP-140 expression and beta-thromboglobulin release (p = 0.017). There was also significantly more debris that accumulated on the arterial filter in the control group, as confirmed by scanning electron microscopy. CONCLUSIONS: This clinical trial has demonstrated a significant difference in the hematologic effects of the test circuits, with evidence of platelet preservation, decreased fibrinolysis, and decreased thrombin generation. A larger trial would be necessary to establish the clinical relevance of these differences.

Circuits with surface modifying additive alter the haemodynamic response to cardiopulmonary bypass.

OBJECTIVE: Blood contact with synthetic surfaces during cardiopulmonary bypass (CPB), inevitably results in the activation of a variety of interrelated pathways of inflammation and coagulation that may contribute to postoperative complications in cardiac surgery patients. The objective of this trial was to evaluate clinical events and complement activation related to the use of a novel biomaterial, into which a surface modifying additive had been incorporated into the polymer used to prepare the bypass circuit. METHODS: A prospective, double-blind trial was carried out with 34 patients randomized to surgery, with either a standard circuit or a circuit treated ('tip to tip') with the surface modifying additive. Variables recorded included perioperative haemodynamics, volume replacement, alpha-agonist and inotrope use. Terminal complement complex (SC5b-9) was measured using an ELISA. RESULTS: Upon initiation of bypass, there was a decrease in mean arterial pressure (MAP) in the control group, not seen in the test group (P = 0.0005, ANOVA). There was a decrease in the total volume of replacement fluid given intraoperatively in the test group as compared with the control group (total plus prime; control 5.3 +/- 1.2 L, test 4.4 +/- 1.9 L, P = 0.03, Mann-Whitney test). There was a trend to decreased need for inotrope infusion in the test group after CPB (test 1/17, control 6/17, Fisher exact test; P = 0.085). No difference was seen in the generation of terminal complement complex between the groups either during or after CPB. CONCLUSIONS: The decrease in blood pressure in the control group, upon the initiation of CPB, did not occur in patients undergoing CPB with the circuit prepared with the surface modifying additive. The decrease in blood pressure was likely associated with the increase in total administered fluids intraoperatively (approximately 1 l/patient) and perhaps the trend towards higher use of inotropes in the control patients as opposed to the test patients. These haemodynamic changes did not appear to be related to complement activation early in CPB.

Platelet-rich-plasmapheresis for minimising peri-operative allogeneic blood transfusion.

BACKGROUND: Concerns regarding the safety of transfused blood have generated considerable enthusiasm for the use of technologies intended to reduce the use of allogeneic blood (blood from an unrelated donor). Platelet-rich plasmapheresis (PRP) offers an alternative approach to blood conservation. OBJECTIVES: To examine the evidence for the efficacy of PRP in reducing peri-operative allogeneic red blood cell (RBC) transfusion, and the evidence for any effect on clinical outcomes such as mortality and re-operation rates. SEARCH STRATEGY: Studies were identified by: computer searches of MEDLINE, EMBASE, Current Contents, and the Cochrane Library (to June 2001). These searches were supplemented by checking the reference lists of published articles, reports, and reviews. SELECTION CRITERIA: Controlled parallel group trials in which adult patients, scheduled for non-urgent surgery, were randomised to PRP, or to a control group who did not receive the intervention. DATA COLLECTION AND ANALYSIS: Main outcomes measured were: the number of patients receiving an allogeneic RBC transfusion, and the amount of RBC transfused. Trial quality was assessed using criteria proposed by Schulz et al. (Schulz 1995) and Jadad et al. (Jadad 1996). MAIN RESULTS: Nineteen trials of PRP were identified that reported data for the number of patients exposed to allogeneic RBC transfusion. These trials evaluated a total of 1452 patients. The pooled relative risk (RR) of exposure to allogeneic blood transfusion in those patients randomised to PRP was 0.71 (95%CI: 0.56, 0.90), equating to a relative risk reduction (RRR) of 29%; the average absolute risk reduction (ARR) was 19% (RD = -0.19: 95%CI: -0.29, -0.09). On average, PRP did not significantly reduce the total volume of RBC transfused (weighted mean difference [WMD] = -0.69: 95%CI: -1.93, 0.56 units). Substantial statistical heterogeneity was observed (p < 0.001). Trials provided inadequate data regarding the impact of PRP on morbidity, mortality, and hospital length of stay. The majority of trials were small and of poor methodological quality. REVIEWER'S CONCLUSIONS: Although the results suggest that PRP is effective in reducing allogeneic RBC transfusion in adult patients undergoing elective surgery, there was considerable heterogeneity in treatment effects and the trials were of poor methodological quality. As the majority of trials were unblinded, transfusion practices may have been influenced by knowledge of the patient's allocation status, potentially exaggerating the true magnitude of the beneficial effect of PRP. The available studies provided inadequate data for firm conclusions to be drawn regarding the impact of PRP on clinically important endpoints.

Right coronary artery injury during tricuspid valve annuloplasty.

An unusual complication after tricuspid valve annuloplasty is described where a ring suture ligated right coronary artery and precipitated myocardial infarct and patient death. The need for caution to prevent this complication with such surgery is emphasized.

Papaverine solutions cause loss of viability of endothelial cells.

OBJECTIVE: The optimal composition of the solution used for irrigation of saphenous veins used for cardiac surgery may influence ultimate graft patency due to potential injurious effects on the vein endothelium of some of the solution constituents. EXPERIMENTAL DESIGN: The viability of cultured saphenous vein endothelial cells was assessed after incubation of saphenous vein endothelial cells with solutions containing saline, saline with papaverine (0.15 M NaCl, 32.5 mg/mL papaverine), culture medium and buffered saline solution (Plasma-Lyte-A). RESULTS: Cell viability was significantly decreased after one hour incubation with solutions containing saline with papaverine (24.4+/-9.4%) as compared to culture medium and buffered saline solutions (medium 100%, Plasma-Lyte-A 86.8+/-6.90%). Loss of viability was directly related to the length of exposure of the cultured cells to papaverine. Morphologic changes of cells incubated with saline: papaverine were also seen including cell retraction and nuclear pyknosis. The cells exposed to medium recovered 100% viability whereas by 4 hours only 22% of the saline: papaverine cells were viable, and by 3 days this viability had fallen to 7.7%. CONCLUSIONS: Loss of viability was shown in cultured saphenous vein endothelial cells exposed to saline solutions containing papaverine, whereas no difference was found between culture medium, saline and balanced salt solutions. Cell death was directly related to the length of exposure of the cells to papaverine. Further, after short- and long-term recovery periods, there was little recovery of cell viability. Although papaverine is a potent vasodilator, exposure to this compound may compromise long-term viability of graft endothelial cells.

Preventive strategies for atrial fibrillation after cardiac surgery in Nordic countries.

BACKGROUND AND AIMS: Atrial fibrillation is a common arrhythmia after cardiac surgery. It increases morbidity, length of hospital stay, and costs of operative treatment. Beta-blockers, sotalol, amiodarone, corticosteroids, and biatrial pacing have been shown to be efficient in the prevention of postoperative atrial fibrillation. The aim of this study was to find out how widely different prophylactic strategies for postoperative atrial fibrillation are used in Scandinavian countries. MATERIAL AND METHODS: An online link for a questionnaire was emailed to (214) cardiac surgeons in Finland, Sweden, Norway, Denmark, and Estonia to assess the use of prophylactic methods for postoperative atrial fibrillation. RESULTS: A total of 97 surgeons responded to the survey. Oral beta-blockers were routinely used for atrial fibrillation prophylaxis by 62% of responders. The main reasons for nonuse of beta-blockers were that responders were unconvinced of the evidence of benefit or they preferred some alternative prophylaxis. Intravenous beta-blockers were used frequently by 6% of responders. Amiodarone was used for prophylaxis by 18% of responders. Nonusers were unconvinced of its efficacy, were afraid of its complications, or found its use too cumbersome. Other prophylactic atrial fibrillation strategies that were used are as follows: sotalol by 2%, magnesium by 17%, corticosteroids by 1%, and atrial pacing by 11% of respondents. CONCLUSIONS: There is still widely varying implementation of strategies for atrial fibrillation prophylaxis among Scandinavian cardiac surgeons. Lack of confidence in the efficacy of these approaches is the main rationale for nonimplementation.

Gender differences in the long-term outcomes after valve replacement surgery.

OBJECTIVE: To compare the long-term outcomes in women and men after valve replacement surgery. DESIGN: Observational study. SETTING: Postoperative aortic valve replacement (AVR) or mitral valve replacement (MVR). PATIENTS: 3118 patients (1261 women, 1857 men) who underwent AVR or MVR between 1976 and 2006 (2255 AVR, 863 MVR), with mean follow-up of 5.6 (4.5) years. MAIN OUTCOME MEASURES: The independent effect of gender on the risk of long-term complications (reoperation, stroke and death) after valve replacement surgery using multivariate actuarial methods. RESULTS: After implantation of an aortic valve bioprosthesis, women had a significantly lower rate of reoperation compared to men (comorbidity-adjusted hazard ratio (HR) 0.4; 95% confidence intervals (CI) 0.2 to 0.9). In contrast, if an aortic mechanical prosthesis had been implanted, women were more at risk for late stroke compared to men (HR 1.7; CI 1.1 to 2.7). After adjustment for age and co-morbidities, women had significantly better long-term survival compared to men after bioprosthetic AVR (HR 0.5; CI 0.3 to 0.6), but there was no survival difference between genders after mechanical AVR. Trends existed towards better survival for women after bioprosthetic MVR (HR 0.6; CI 0.4 to 1.0) and mechanical MVR (HR 0.8; CI 0.5 to 1.1). CONCLUSION: The long-term outcomes after valve replacement surgery differ between women and men. Although women have more late strokes after valve replacement, they undergo fewer reoperations and have better overall long-term survival compared to men.