Postoperatively increased serum alanine aminotransferase level is closely associated with mortality after cardiac surgery.

BACKGROUND: Hepatic biomarkers are often not assessed routinely after cardiac surgery. Alanine aminotransferase (ALT) has become the primary biomarker of any type of liver injury. Our purpose was to study the prognostic value of serum ALT in early and late mortality. METHODS: Patients subjected to any type of cardiac operation from January 1999 through December 2010 were studied. According to postoperative maximum ALT level, four groups were created: group 1 = ALT ≤ 50 U/L (n = 8,669), group 2 = ALT 50 to 150 U/L (n = 3,055), group 3 = ALT 151 to 500 U/L (n = 248), and group 4 = ALT > 500 U/L (n = 50). Cox multivariate modeling was used for survival analysis. RESULTS: Patients in groups 3 and 4 had increased 30-day mortality (hazard ratio [HR] = 8.07 [4.15-15.69], p < 0.001 and HR = 19.07 [9.88-36.80], p < 0.001, respectively). Late mortality was increased for group 4 after final adjustments (HR = 1.87 [1.18-2.95], p = 0.007). CONCLUSION: Elevated postoperative ALT level (above 150 U/L) is closely associated with early mortality after cardiac surgery. ALT level above 500 U/L implies a substantial liver dysfunction with a considerable negative association on both early and late survival.

Postcardioplegia ventricular fibrillation: no impact on subsequent survival.

OBJECTIVES: At aortic declamping after cardioplegic cardiac arrest, the initial rhythm can be broadly classified as ventricular fibrillation (VF) or non-VF. VF can be treated with potassium-induced conversion and direct-current countershock is only applied if potassium treatment fails. We aimed to investigate whether there are any differences between these groups of patients in regard to outcomes. DESIGN: From January 1999 through December 2010, 12,113 patients underwent various types of cardiac surgery. Data from every patient were consecutively registered. Survival was established through the Norwegian National Registry. Cox multivariable modeling with adjustment for clinical, biochemical, and medication baseline data was used for survival analysis. RESULTS: The mean follow-up time was 7.4 years and total patient-years were 89,268. The percentage of all-cause deaths was 24.9. Adjusted survival for patients with no postcardioplegia VF (n = 9723) and patients with successful potassium-induced conversion (n = 1877) was completely identical. Four hundred patients with electrical conversion after failed potassium treatment had a nonsignificant trend toward an increased mortality (hazard ratio, 95% confidence interval: 1.19 (0.99-1.4); p = 0.07). CONCLUSIONS: This is the first study reporting the association between postcardioplegia VF, its treatment with potassium and outcome. No impact was found on outcome as judged by all-cause mortality.

Mediastinitis after coronary artery bypass grafting increases the incidence of left internal mammary artery obstruction.

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 after coronary artery bypass grafting: the effect of vacuum-assisted closure versus traditional closed drainage on survival and re-infection rate.

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.

Immediate rescue operations after failed diagnostic or therapeutic cardiac catheterization procedures.

OBJECTIVES: Although rare, life-threatening complications requiring emergency cardiac surgery do occur after diagnostic and therapeutic cardiac catheterization procedures. The operative mortality has been persistently reported to remain high. The purpose of this observational study was to evaluate and report the outcomes, with particular emphasis on early mortality, of these risky operations that were performed in a single highly specialized cardiac centre. METHODS: Between June 1997 and August 2007, 100 consecutive patients, 13 after diagnostic complicated cardiac catheterization (0.038% of 34,193 angiographies) and 87 after crashed percutaneous coronary intervention (PCI; 0.56% of 15,544 PCIs), received emergency operations at the Feiring Heart Center. In the same period, 10,192 other patients underwent open cardiac surgery. Early outcome data were analysed and compared between the cohorts. Follow-up was 100% complete. RESULTS: The preoperative status of the 100 patients was that 4 had ongoing external cardiac massage, 24 were in cardiogenic shock, 32 had frank enduring ST-segment infarction but without shock and 40 had threatened acute myocardial infarction. There was 1% (1 patient) 30-day mortality in the study group, which is equal (0.9%, P=0.60) to that of all other operations. Postoperative myocardial infarction and prolonged ventilator use were significantly higher in the crash group, whereas the rate of stroke, renal failure, reopening for bleeding and mediastinitis were similar between the groups. CONCLUSIONS: With rapid transfer to an operation room, minimizing the time of warm myocardial ischaemia, and by performing complete coronary revascularization, it is possible to obtain equally low operative mortality in patients with life-threatening cardiac catheterization-associated complications, as is the case with open cardiac operations in general.

Avoidance of noninfectious sternal dehiscence: figure-of-8 wiring is superior to straight wire closure.

OBJECTIVES: Comparison of figure-of-8 wiring or simple straight-wiring technique assessed by the frequency of early noninfectious sternal dehiscence. DESIGN: Observational register study with 7835 patients having sternal closure with figure-of-8 steel wires was compared with 2122 patients, where the sternotomy was closed by simple interrupted straight wires. The endpoint was the rate of early (within 30 days) sterile sternal dehiscence. RESULTS: Fourteen patients (0.66%) with single wires and five patients (0.06%) with figure-of-8 wires underwent re-operation for nonmicrobial sternal disruption (p < 0.0001). The median time-point for re-intervention was 6 days for both groups. In more than 6000 patients, the sternotomy was closed with five figure-of-8 wires without dehiscence in any of them. CONCLUSION: In a large cohort of consecutive cardiac operations, it was found that sternal closure with figure-of-8 wires is better than closure with simple interrupted wires.

Potassium-induced conversion of ventricular fibrillation after aortic declamping.

OBJECTIVES: The anti-fibrillatory effect of potassium is well recognized from experimental models. There have, however, been very few clinical reports on the use of potassium to convert ventricular fibrillation (VF) after cardioplegic arrest. METHODS: In total, 8465 adult patients undergoing cardiac operations on cardiopulmonary bypass (CPB) and with cold antegrade crystalloid cardioplegic arrest were consecutively enrolled in a database. Patients with VF after removal of the aortic clamp were given 20 mmol potassium, and if needed an extra 10 mmol, in the perfusion line and the conversion rate was registered. Preoperative and intraoperative factors possibly related to the occurrence of post-ischaemic VF were assessed. RESULTS: Of these, 1721 (20%) patients had VF and 1366 of these (79%) were successfully treated with potassium infusion. Only 355 (21%) patients (4% of all operations) had direct-current countershock. The need for pacing was lower in the treatment group compared with the non-treatment group (P <0.001). Multivariate analysis revealed as the main findings that age, gender, amount of cardioplegia related to body mass index (BMI), and blood transfusion during the time of CPB had a highly significant (P <0.001) impact on reducing the rate of post-arrest VF. Somewhat contrary to expectation, left ventricular hypertrophy (LVH) was not a significant factor (P = 0.32) for post-arrest VF. No conversion by potassium was significant for age (P <0.001), gender (P <0.001) and LVH (P <0.001), but not for blood transfusion during CPB (P = 0.38) and for the ratio of cardioplegia-BMI (P = 0.26). CONCLUSIONS: The results from this register study demonstrate that potassium infusion is an effective and convenient first-hand measure to convert post declamping VF on CPB.

Long-term survival after aortic valve replacement in octogenarians and high-risk subgroups.

OBJECTIVES: The increasing age in the population and improvements in the treatment options for aortic valvular disease have resulted in a considerable rise in the number of elderly patients being admitted for conventional aortic valve surgery. Recently, transcatheter aortic valve implantation (TAVI) has been developed as a less invasive treatment option. However, both open heart surgery and transcatheter treatment have serious complications. Thus, the knowledge of contemporary results of conventional surgery is important in guiding treatment allocation. METHODS: From the database at Feiring Heart Clinic, 1525 patients were identified who had undergone aortic valve replacement from 1999 to 2010; of these, 361 patients were more than 80 years of age. The population was followed for all-cause mortality until March 2011, with special reference to the age group older than 80 years and other high-risk subsets. RESULTS: The short-term mortality was 2.2% in the whole population and 3.9% in octogenarians. Five-year survival was 83.1 and 68.1%, respectively. In the high-risk subgroup of patients with a logistic EuroSCORE above 20%, the equivalent figures were 4.2 and 72.7%. CONCLUSIONS: Contemporary results after conventional aortic valve surgery are excellent in both short- and long-term survival and should not be withheld in the elderly or otherwise high-risk populations. The logistic EuroSCORE grossly overestimates the operative risk and should be used with caution in allocating patients to TAVI instead of conventional surgery.

Randomized prospective trial of saphenous vein harvest site infection after wound closure with and without topical application of autologous platelet-rich plasma.

OBJECTIVE: Wound infection is still a common problem after open long saphenous vein harvesting. Platelets are important for the healing process. The hypothesis was that spraying of the wounds with platelet-rich plasma might reduce the frequency of harvest site infections. METHODS: From January to October 2008, 140 patients undergoing first-time coronary artery bypass grafting were randomized into two groups of 70 patients. Both groups had standard surgical leg wound closure and care except topical application of platelet-rich plasma as adjunctive treatment in the active treatment group. End points were wound infection and cosmetic result at 6 weeks. RESULTS: The follow-up was 100% complete. Nine patients (13%) in the treatment group and eight (11%) in the control group experienced harvest site infection (p=0.80). The overall cosmetic result was also similar between the groups (p=0.34), but the top score was borderline and more frequent in the treatment group (p=0.050). CONCLUSION: Topical application of autologous platelet-rich plasma on vein harvest wounds did not reduce the rate of surgical site infection.

[Anaesthesia for open-heart surgery in adults]. / Anestesi ved åpen hjertekirurgi hos voksne.

BACKGROUND: Each year, about 5 000 adults undergo heart surgery (most of them open-heart surgery) in Norway. The purpose of this overview is to address specific problems associated with anaesthesia in these patients. MATERIAL AND METHODS: The paper is based on literature identified through a non-systematic search in PubMed and own experience with clinical work and research. RESULTS: In Norway, general anaesthesia is always used in open-heart surgery. Some patients have such severely impaired heart function that it needs to be supported by inotropic drugs or mechanical devices. The patients are given heparin during surgery, and many also receive preoperative treatment with drugs that affect haemostasis. Profuse bleeding, during or after surgery, is sometimes challenging. The brain is at risk because the blood flow generated by the heart-lung machine is unphysiological, and because air or solid particles may embolize from the heart or aorta during the intervention. Renal failure after heart surgery is a serous complication with high mortality. Some anaesthetics probably have direct cardioprotective effects. Tight control of blood glucose seems to be justified, even if the level of optimal serum blood glucose is still debated. INTERPRETATION: Several organ systems are at risk during heart surgery. In addition to providing pleasant and painless sleep for the patient and good working conditions for the surgeon, the anaesthetist cooperates with the team about securing optimal organ protection.

The effect of dexamethasone on side effects after coronary revascularization procedures.

UNLABELLED: Corticosteroids decrease side effects after noncardiac elective surgery. We designed this randomized, double-blinded, placebo-controlled study to test the hypothesis that standard doses of dexamethasone (4 mg x2) would reduce postoperative nausea, vomiting, and pain, decrease the incidence of atrial fibrillation (AF), and improve appetite after cardiac surgery, thereby facilitating the recovery process. A total of 300 patients undergoing coronary revascularization surgery were enrolled in this clinical study. The anesthetic management was standardized in all patients. Dexamethasone (4 mg/mL) or saline (1 mL) was administered after the induction of anesthesia and a second dose of the same study drug was given on the morning after surgery. The incidence of AF was determined by analyzing the first 72 h of continuously recorded electrocardiogram records after cardiac surgery. The patients were assessed at 24- and 48-h intervals after surgery, as well as at the time of hospital discharge, to determine the incidence and severity of postoperative side effects (e.g., nausea, vomiting, pain) and patient satisfaction scores. Dexamethasone significantly reduced the need for antiemetic rescue medication on the first postoperative day (30% versus 42%), and the incidences of nausea (15% versus 26%) and vomiting (5% versus 16%) on the second postoperative day (P < 0.05). In addition, dexamethasone significantly reduced the percentage of patients with a depressed appetite on the second postoperative day. However, the corticosteroid failed to decrease the incidence of AF (27% versus 32%) or the total dosage of opioid analgesic medication administered in the postoperative period. We conclude that dexamethasone (8 mg in divided doses) was beneficial in reducing emetic symptoms and improving appetite after cardiac surgery. However, this dose of the corticosteroid does not seem to have antiarrhythmic or analgesic-sparing properties. IMPLICATIONS: Dexamethasone (8 mg IV) was beneficial in reducing emetic symptoms and increasing appetite after cardiac surgery. However, this dose of the corticosteroid failed to decrease postoperative pain or the incidence of new-onset atrial fibrillation.