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Atrial fibrillation (AF) is a common arrhythmia among patients scheduled for open heart surgery and is associated with increased morbidity and mortality. According to international guidelines, symptomatic and selected asymptomatic patients should be offered concomitant surgical AF ablation in conjunction with valvular or coronary surgery. The gold standard in AF surgery is the Cox Maze III ("cut-and-sew") procedure, with surgical incisions in both atria according to a specified pattern, in order to prevent AF reentry circuits from developing. Over 90% of patients treated with the Cox Maze III procedure are free of AF after 1 year. Recent developments in ablation technology have introduced several energy sources capable of creating nonconducting atrial wall lesions. In addition, simplified lesion patterns have been suggested, but results with these techniques have been unsatisfactory. There is a clear need for standardization in AF surgery. The Swedish Arrhythmia Surgery Group, represented by surgeons from all Swedish units for cardiothoracic surgery, has therefore reached a consensus on surgical treatment of concomitant AF. This consensus emphasizes adherence to the lesion pattern in the Cox Maze III procedure and the use of biatrial lesions in nonparoxysmal AF.

Objectives: To assess the effects of intraoperative left atrial epicardial cryoablation on rhythm and atrial and ventricular function., Design: Thirty five patients with coronary artery disease and documented atrial fibrillation underwent coronary artery bypass surgery and concomitant cryoablation. An age and gender matched control group of 35 patients with atrial fibrillation underwent bypass surgery alone. Echocardiography was performed 9 ? 32 days before and 22 ? 6 months after surgery., Results: The proportion of patients in sinus rhythm at follow-up was 63% and 34% (p = 0.04) in the cryoablation and control groups, respectively. In patients with sinus rhythm both before surgery and at follow-up, the left atrial area increased (p = 0.002) and the mitral annular excursion during atrial contraction decreased (p = 0.01) after cryoablation. The mitral flow velocity during atrial systole decreased after cryoablation (p = 0.002). The LV diameter increased (p = 0.03) and the left ventricular ejection fraction (LVEF) decreased (p = 0.03) in cryoablated but not in control patients. Continued deterioration was seen in patients with atrial fibrillation both pre- and postoperatively., Conclusions: At long-term follow-up, a significantly higher proportion of patients was in sinus rhythm in the cryoablation than in the control group. The atrial and ventricular function had decreased at follow-up two years after surgery. This decrease was small and occurred within or close to the reference values in patients with sinus rhythm at follow-up, while patients remaining in atrial fibrillation showed a significant continued deterioration. Some subgroups were small, and the findings, although statistically significant, should be interpreted with caution.

Non-inferiority trials are questionable when death and serious complications are included among outcomes. The term itself "non-inferiority" is misleading, since such a study would not demonstrate that a new treatment is non-inferior to a control treatment, but simply that the inferiority would not reach a pre-specified level, deemed as acceptable by the designers of the trial. Group cross-over, assay-sensitivity and the need of a placebo arm are major issues for the reliability of non-inferiority trials. The SYNTAX trial for severe coronary artery disease was designed on a non-inferiority margin of 6.6%. In this paper we show that the SYNTAX designers were ready to accept up to 30% higher rate of death and major adverse events to claim the non-inferiority of percutaneous coronary intervention versus coronary artery bypass grafting. Eventually the SYNTAX study failed because percutaneous patients sustained an even higher rate of adverse events. We propose major caution in performing non-inferiority randomized trials.

Objective: Early and long-term survival in patients suffering from cardiogenic shock is poor. Treatment with mechanical assist devices is complicated and expensive but claim to improve survival. We reviewed our experience of venoarterial extracorporeal membrane oxygenation (ECMO) in patients with acute cardiogenic shock., Design: ECMO was used in 52 patients with cardiogenic shock. They were divided into those not operated upon previously (n=19) and those having had cardiac surgery prior to circulatory collapse (n=33)., Results: Twenty-six patients were weaned from ECMO. Early mortality for all patients was 48%. Mortality beyond 30 days was 5.8%, with no mortality in the non-cardiotomy group. Long-term survival for patients in the non-cardiotomy group was 63%, as compared to 33% in post-cardiotomy patients (p=0.07). Age over 55 years, female gender or cannulation site did not appear to influence survival., Conclusion: Mortality for patients in cardiogenic shock is very high. Treatment with ECMO in patients with refractory cardiogenic shock can be performed with good survival especially in non-surgical patients.

Background: Cardiac surgery induces a systemic inflammatory activation and alterations in the hemostatic cascade. The responses contribute to postoperative complications but may also have protective effects. We investigated the relationship between inflammation, hemostasis and bleeding after off-pump coronary artery bypass surgery (OPCAB)., Methods: Ten OPCAB patients were included in a prospective descriptive study. Selected markers of inflammation (IL-6, IL-8, PMN-elastase, C3a, and SC5b-9), and hemostasis (platelet count, ss-thromboglobulin, anti-thrombin, D-dimer and fibrinogen) were measured before and immediately after surgery. Postoperative bleeding was registered., Results: Inflammatory variables did not alter significantly during surgery while ss-thromboglobulin concentrations increased and anti-thrombin and fibrinogen decreased. There were significant postoperative correlations between PMN-elastase and ss-thromboglobulin (r=0.82, p=0.004), between PMN-elastase and fibrinogen (r=0.69, p=0.03) and between C3a and ss-thromboglobulin (r=0.71, p=0.02). In addition, there were significant inverse correlations between postoperative bleeding and pre- and postoperative fibrinogen levels (r=-0.76, p=0.011 and r=-0.84, p=0.002 respectively), between bleeding and postoperative ss-thromboglobulin levels (r=-0.66, p=0.04) and between bleeding and postoperative PMN-elastase (r=-0.75, p=0.01)., Conclusions: The results give further evidence for an association between the inflammatory response and hemostasis after cardiac surgery.

Objective: To investigate the time course of troponin-T release into the extracellular fluid of the myocardium and to distinguish between a rise in troponin-T due to implantation trauma and an increase due to cardiac arrest during coronary surgery., Design: Microdialysis probes were implanted in the heart of seven patients soon after sternotomy. Troponin-T was measured in the microdialysates and in peripheral blood from 3 h before to 24 h after heart arrest., Results: The troponin-T concentration in the microdialysates increased immediately after probe implantation and decreased to baseline within 70 min. This early peak is interpreted to reflect a local trauma. Three hours after cross-clamp release, a second peak of microdialysate troponin-T was recorded; 50 times higher than in serum. Eight to 24 h later a third peak occurred in five patients. Serum troponin-T was below the detection level at the beginning of the operation but increased linearly during the first 3 h of reperfusion and remained at that level thereafter., Conclusion: Microdialysis is a safe technique providing more information on myocardial metabolism during and after bypass surgery than can be obtained from peripheral blood. The release of troponin-T in response to cardiac arrest can be distinguished in time from the local tissue response to probe implantation.

From April 1996 to October 1998, 250 patients with a mean age of 63 years (31-86 years) underwent coronary artery bypass grafting using the off-pump technique. The prime reason for using this technique was the need to minimize the surgical trauma by avoiding extracorporeal circulation. Fifty-seven percent of the patients had 1-vessel disease, 39% had 2-vessel disease and 4% 3-vessel disease. Sternotomy was performed in 196 patients and an anterior mini-thoracotomy in 54 patients. The mean number of coronary anastomoses was 1.5. Perioperative mortality was 0.4%. The first consecutive 87 patients underwent an early postoperative coronary angiography (days 1-5) revealing a graft patency of 96.5%. Five out of the 7 patients with occluded grafts subsequently underwent another intervention (surgical revascularization in 4 patients and percutaneous transluminal coronary angioplasty in one); 1.2% developed transmural myocardial infarction and 2.8% were reoperated upon for bleeding. The mean time of ventilatory support was 2.5+/-0.5 h. The mean ICU time for all patients was 12 h (0-10 days). The mean in-hospital time was 7 days (2-30 days). Coronary artery bypass surgery without the use of extracorporeal circulation is a safe procedure that can be performed with limited need for intensive care resources. However, long-term results remain to be investigated.

To identify preoperative biopsychosocial factors characterizing patients who will experience chest pain (self-reported) one year after coronary artery bypass grafting (CABG), 111 patients under 61 years of age were evaluated by questionnaire before CABG and 12 months postoperatively. A "Coronary Health Profile" was evolved to study quality-of-life indicators, e.g. "Sense of Coherence" (SOC), emotional state (loneliness, depressed mood, stress, anxiety) and social support as well as experience of chest pain, and the results were correlated to biomedical data. Chest pain was experienced in the first postoperative year by 34% of the patients. These patients, who were younger than those without chest pain, generally had a body mass index >25, as well as lower preoperative values for SOC, poorer emotional state and social support. Independent predictors in a multivariate stepwise logistic regression analysis were moderate/weak SOC, ejection fraction <50%, and moderate/severe mood depression. We conclude that biomedical as well as psychosocial factors have a significant impact as predictors of chest pain (of any origin) after CABG, and must be considered in preoperative evaluation. The findings indicate the need for biopsychosocial support/intervention before as well as after CABG.

FK 506 (FK) has a strong immunosuppressive effect, but a low-grade, dose-dependent nephrotoxicity and diabetogenicity, which means that reducing the dose of FK is of considerable interest. Lipo-prostaglandin E1 (LPGE1) is a preparation of PGE1 that has potent immunosuppressive properties, and its duration of action is longer than that of ordinary PGE1. The purpose of this study was to investigate whether LPGE1 can enhance the immunosuppressive effect of FK. Heterotopic cardiac transplantations to the neck vessels were performed, and recipient rats were treated with intramuscular injections of FK and LPGE1 once daily for 10 days. All grafts without any treatment were rejected within 14 days. In comparison, the FK doses of 0.07, 0.2 and 1.0 mg/kg/day for 10 days significantly increased the long-term graft survival (>100 days) to 8%, 44% and 100%, respectively. The addition of LPGE1 to the first two dosages caused a further significant increase in the graft survival, to 18% and 80%, respectively, when compared with the control. LPGE1 appears to enhance the immunosuppressive effect of FK.

Microdialysis probes permeable to large molecules (m.w. cut-off > 200 kD) were introduced into the myocardium of anaesthetized pigs in order to evaluate their potential for early detection of myocardial ischaemia and enzyme markers for infarction. The left anterior descending coronary artery was occluded for 30 min and the myocardium was reperfused for 3 h. The concentrations of aspartate aminotransferase (ASAT), lactate, glucose and selected free amino acids were measured. The levels in the interstitium of ischaemic and non-ischaemic myocardium were compared with those in plasma from the coronary sinus as well as from a peripheral vein. Twelve probes were inserted in six pigs and withdrawn after 8-72 hours of sampling. No complications occurred. Simultaneous 100% increase of ASAT and lactate was found in myocardial dialysates after 30 min of ischaemia. ASAT activity remained at that level until the end of reperfusion. The plasma peak ASAT level was not attained until after 3 h. Glutamate was the only amino acid which increased significantly in the myocardial interstitium during ischaemia, peaking after 30 min of reperfusion. Dialysates from the unaffected myocardium showed no effects on lactate, ASAT or glutamate. The use of myocardial microdialysis for pre- and postoperative recordings in man is discussed.