Coronary Artery Bypass Surgery Surgery Research Articles

Patient preferences for treatment for angina: An overview of findings from three studies

Access to cardiac treatments has been documented to vary with patients' age. It is unknown whether these variations reflect patients' treatment preferences. We aimed to investigate patients' preferences for cardiology treatments and develop a Patients' Preferences Questionnaire. Semi-structured interviews with primary care patients with diagnosed angina with postal follow-up. The resulting Patients' Preferences Questionnaire was tested with newly admitted inpatients with acute coronary syndrome and with patients in primary care. The Patients' Preferences Questionnaire was psychometrically sound. Analyses of preference subscale scores showed that the most positive preference scores were for medication. Angioplasty scored highest at the negative end of the scale. Detailed analyses showed that older people and women were less likely to prefer coronary artery bypass surgery (CABG), reflecting its greater level of invasiveness. Older people (aged over 75 years, compared to people aged under 75 years), but not women, were also more cautious in their strength of preference for angioplasty. More positive attitudes towards CABG surgery, and more negative attitudes towards medication, were associated with greater impact of the condition on life. The research resulted in a psychometrically sound Patients' Preferences Questionnaire. There was some evidence to support the view that older people's weaker preferences for CABG may contribute slightly to variations in the provision of re-vascularization. There was also variation in preferences within age groups, cautioning against the assumption that all or most older people are more reluctant than younger people to undergo invasive procedures.

Cardiac regeneration by intramyocardial stem cell therapy: clinical development

Cardiac stem cell therapy provides novel therapeutic options for chronic ischemic heart disease, but the potential of autologous human bone marrow progenitor cells remains to be evaluated for chronic ischemic cardiac disease. In a clinical phase I trial, which was started in June 2001, we first assessed the feasibility and safety of intramyocardial CD133+ bone marrow cell injection together with coronary artery bypass surgery (CABG) in chronic ischemic heart disease. In the initial safety study, we treated 15 patients and found that left ventricular ejection fraction (LVEF) increased significantly from 39.0 ± 8.7% pre‐operatively to 50.2 ± 8.5% at 6 months and 47.9 ± 6.0% at 18 months (F = 6.03, P = .012, repeated‐measures ANOVA). No procedure‐related complications were observed for up to 3 years. In a subsequent prospective randomized controlled Phase II efficacy trial, 40 patients received either CABG and cell therapy or CABG alone. Here, we observed that in the CABG & cell therapy group, LVEF increased from 37.4 ± 8.4% to 47.1 ± 8.3% at 6 months (F = 24.16,P < .0001, repeated‐measures ANOVA), whereas from 37.9 ± 10.3% to 41.3 ± 9.1% in CABG‐only group (F = 7.72, P = .012). LVEF was significantly higher at 6 months in the CABG & cell therapy group than CABG only (P = .03). Similarly, perfusion in the infarcted myocardium improved more in CABG & cell‐treated patients than in CABG‐only patients. Follow‐up time currently ranges between 27 and 62 months with mean follow up of 44 ± 12 months and encompasses a total of 572 patient months (as of April 2007). In these patients no relevant ventricular arrhythmia was recorded at any time point. There were no adverse tissue changes (e.g. intramyocardial calcification or tumor formation) in the computed tomography. To date long‐term follow‐up functional tests are proceeding. From 35 patients who were treated with stem cell injection (phase I and phase II), one was excluded from the study and two deaths occurred as mentioned above. Among 32 patients remained in the study 13 patients underwent long‐term safety investigations as of April 2007. For further clinical introduction a phase III study is planned to be started in summer 2008 including the heart center in Berlin (DHZB), Hannover (MHH), and Rostock. This will be a placebo controlled, prospective, randomized, double‐blind multicenter, phase III, clinical trial investigating the effects of intramyocardial injection of 5 ml CD133+ bone marrow cells or placebo in 142 patients with coronary artery disease scheduled for CABG surgery. Patients will be randomized to one of the two treatment groups (CD133+ or placebo) in a 1 : 1 ratio. Intramyocardial highly purified CD133+ bone marrow stem cell delivery in CABG patients is safe and provides beneficial effects, though it remains to be proven whether these effects produce a lasting clinical advantage. This therapeutical experience opens a clinical window for cardiac cell therapy as a standard therapy in chronic ischemic heart disease involving primary isolated stem cells. Improved application techniques of primary, cultured, and modified stem cells may prompt the way to establish new treatment possibilities for congenital and adult cardiac disease in the future.

Functional outcome and quality of life after coronary artery bypass surgery in patients with severe heart failure and hibernated myocardium

Myocardial viability is an important parameter, predictive of improvement in left ventricular function after coronary artery bypass surgery (CABG). We wanted to define the relationship between the extent of hibernated myocardium and improvement in ejection fraction function and quality of life after CABG. Sixty-five consecutive patients with ischaemic cardiomyopathy (mean LVEF <40%) undergoing surgical revascularization were studied with (99m)Tc-sestamibi myocardial perfusion Gated SPECT imaging (MPI) to assess preoperative myocardial viability. Patients were divided into two groups, based on the extent of viable myocardium before CABG: group 1, 39 patients with more than four viable segments; and group 2, 26 patients with fewer than four viable segments. Regional and global ejection fraction function, heart failure symptoms and quality of life were measured before and 14+/-4 months after revascularization. We used bull's eye quantitative analysis of MPI scans and a 17-segment model of ejection fraction function and perfusion evaluation. The number of viable segments per patient was directly related to the improvement in LVEF after revascularization (r=0.79, P<0.01). Patients with more than four viable segments representing 24% of the left ventricle yielded the sensitivity of 83% and specificity of 79%, respectively, for predicting improvement in LVEF. Furthermore, the presence of four or more viable segments predicted improvement in heart failure symptoms and quality of life after revascularization. The presence of more than four viable segments (24% of the left ventricle) on MPI in patients with ischaemic heart failure before CABG surgery is significantly correlated with the improvement in LVEF, heart failure symptoms and quality of life post-operatively.

The Shelhigh No-React® bovine internal mammary artery: a questionable alternative conduit in coronary bypass surgery?☆

Increasing age and comorbidities among patients undergoing coronary artery bypass surgery (CABG) stimulates the exhaustive research for alternative grafts. No-React treatment should render the tissue resistant against degeneration and reduce early inflammatory response. The aim of the present study was an invasive assessment of the patency of No-React bovine internal mammary artery (NRIMA grafts) used as bypass conduit in CABG surgery. Nineteen NRIMA grafts were used in 17 patients (2.9%) out of a total of 572 patients undergoing CABG surgery within a 12-month period. All intraoperative data were assessed and in-hospital outcome was analysed. Follow-up examination was performed 7.0+/-4.0 months after initial surgery, including clinical status and coronary angiography to assess patency of the NRIMA grafts. Average perioperative flow of all NRIMA grafts was 71+/-60 ml/min. One patient died in hospital due to a multi-organ failure. Four patients refused invasive assessment. Follow-up was complete in 12 patients with overall 13 NRIMA grafts. Nine NRIMA grafts (69.2%) were used for the right coronary system, two NRIMA grafts (15.4%) on the LAD and two on the circumflex artery. Graft patency was 23.1% and was independent of the intraoperative flow measurement. NRIMA grafts show a very low patency and cannot be recommended as coronary bypass graft conduits. Patency was independent of the perioperative flow, assessed by Doppler ultrasound. Because of this unsatisfying observation, this type of graft should be utilised as a last resource conduit and used only to revascularise less important target vessels, such as the end branches of the right coronary artery.

La proportion de variation dans les pratiques transfusionnelles périopératoires au Canada imputable aux hôpitaux

Hospital variation in transfusion practices has been described previously but the proportion of variation attributable to the hospital has not. The objective of this report was to quantify hospital variation in red cell transfusion decisions perioperatively for patients undergoing coronary artery bypass surgery (CABG). We used a cross-sectional study design using pretested self-administered mailed questionnaires sent to all anesthesiologists and cardiac surgeons involved in CABG in Canada. Responses were received from anesthesiologists from all 32 hospital sites and from cardiac surgeons from 30/32 sites (94%). There was variation attributable to the hospital in transfusion triggers selected (P<0.0001). For patients who had uncomplicated CABG surgery, the range of transfusion triggers among hospitals for the intraoperative and postoperative case scenarios were 61 to 80 gxL(-1) and 64 to 80 gxL(-1), respectively. The hospital accounted for 20% of the variation in the transfusion practice intraoperatively and postoperatively. The remainder of the variation was attributable to the individual physician. Academic affiliation and the number of surgical cases performed at the hospital were not significant factors impacting on the transfusion triggers selected This is the first study to quantify the variation in red cell transfusion practices according to individual physicians and the hospital. The variation attributed to the hospital is significant. The explanation for the variation in transfusion decisions that relate to the hospital needs to be explored further in order to help optimize transfusion practice.

Abstract 2860: Efficacy and Safety of Vernakalant Hydrochloride Injection for the Treatment of Atrial Fibrillation After Valvular or Coronary Artery Bypass Surgery

Introduction: Postoperative atrial fibrillation (AF) and atrial flutter (AFL) are common after cardiac surgery. This study evaluated the efficacy and safety of vernakalant hydrochloride, a novel atrial selective, frequency- and voltage-dependent Na + and early activating K + channel blocker, in converting AF or AFL to normal sinus rhythm (SR) after coronary artery bypass surgery (CABG), valvular surgery, or both. Methods : This multicenter, double-blind, randomized, placebo-controlled trial included patients aged ≥18 years who had normal SR preceding surgery; had undergone CABG or valvular surgery; and had documented, sustained (3–72 hours) AF or AFL between 24 hours and 7 days after CABG or valvular surgery. Patients were randomly assigned in a 1:2 ratio to receive a 10-min infusion of placebo or vernakalant 3 mg/kg. After 15 min, a second 10-min infusion of placebo or vernakalant 2 mg/kg was given, if AF or AFL persisted. Postdose evaluations included 24-hr Holter monitoring, 12-lead ECG recordings, and assessment of vital signs and AF/AFL symptoms. The primary efficacy measure was conversion to SR for at least 1 minute within 90 min of first exposure. Results : Of 190 patients randomized, 161 received treatment (54 placebo and 107 vernakalant). The main reason for not receiving treatment was spontaneous conversion to SR (7 placebo and 17 vernakalant). Among the patients given treatment, 67% had undergone CABG, 24% had valvular surgery, and 9% had both. The mean age was 68 years, and most patients were men (75%) and white (94%). At entry, 93% of patients had AF, 6% had AFL, and 1% had neither. Conversion to SR within 90 minutes was observed in 45% of patients given vernakalant and 15% of those given placebo ( P = .0002). Of the patients converting to SR with vernakalant, the median time to conversion was 12 minutes and 75% converted on the first dose. In the 24-hr period following study drug administration, adverse events were reported in 32% and 38% of patients given placebo and vernakalant, respectively, of which 2 were serious (complete AV block and hypotension) in the vernakalant group. There were no deaths or cases of torsade de pointes. Conclusions : Vernakalant was effective and well tolerated in the conversion of AF and AFL to SR after CABG, valvular surgery, or both.

Abstract 3040: Coronary Artery Bypass Surgery In 14,956 Patients With Cardiogenic Shock: The Society Of Thoracic Surgeons National Database Experience

Background . While only a small minority of patients undergo coronary artery bypass surgery (CABG) in the setting of cardiogenic shock (CS), these patients face a high risk for mortality and morbidity. There exist few studies that characterize clinical features and outcomes in CS patients undergoing CABG in contemporary community practice. Methods . We evaluated data of 14,956 patients with CS in comparison with 693637 without CS undergoing CABG between 2002 and 2005 at hospitals participating in the Society of Thoracic Surgeons National Database. Clinical, angiographic and operative features and in-hospital outcomes were studied in patients with and without CS. Results . Patients with preoperative CS constituted 2.1% of patients undergoing CABG yet accounted for 16% of all CABG deaths. These patients had greater comorbid conditions and left main disease and lower left ventricular ejection fraction. In-hospital events and length of hospital stay (median 96 vs. 36 days) were significantly higher in CS patients. Operative mortality was high (rising from 20% for isolated CABG, to 33% for CABG+ valve surgery, to 58% for CABG+ ventricular septal repair). While mortality for CABG surgery overall has declined significantly overtime (p for trend&lt; .0001), mortality for CS patients have not changed significantly over the 4 year study period (p= .07, Figure ). Conclusions . Patients with CS represents minority of patients undergoing CABG, yet with persistently high operative risks. These patients in fact account for 1 of every 7 deaths in patients undergoing CABG. Ongoing efforts are warranted to continuously develop and evaluate new strategies to improve outcomes of these patients.

Neurocognitive Changes After Coronary Bypass Surgery

In this issue of Circulation , Djaiani and associates report that the processing of shed blood with a cell saver resulted in a significant reduction in postoperative neurocognitive dysfunction after coronary artery bypass surgery (CABG) in elderly patients.1 The authors further implied that this significant improvement in neurocognition was a result of less lipid embolization in those patients in whom a cell saver was used. The study was a randomized double-blinded trial that compared the use of a cell saver with cardiotomy suction (defined as control). Cardiotomy suction is a standard component of cardiopulmonary bypass (CPB), in which shed blood in the mediastinum is suctioned to a venous reservoir, where it is collected and then periodically reinfused through the arterial circuit to the patient. This technique was not used in patients in the cell saver group, but rather shed blood was suctioned via the cell saver system and processed, and red blood cells alone were infused to the patient through a similar arterial circuit. A standard 32-μm filter was used in the arterial pressure line in both groups. Article p 1888 Elderly patients who underwent CABG were chosen because it has been documented that these individuals are at increased risk to develop neurological dysfunction after cardiac surgery. The study was powered (n=209) to see a 50% reduction in cognitive dysfunction with additional patients added (for a total of 226 patients) to compensate for potential drop out, which turned out to be similar in both groups. The primary end point of neurocognitive evaluation was based on a battery of standardized and validated tests used to assess neuropsychological outcome. Evaluation was done at baseline and on follow-up at 6 weeks. In addition to neurocognitive decline, Figure 1 in Djaiani et al also demonstrates improvement in the battery of 12 tests documenting …

Cardiovascular Surgical Outcomes in Patients with the Antiphospholipid Syndrome—A Case-Series

Patients with the antiphospholipid syndrome (APLS) have severe involvement of the cardiovascular apparatus and often need surgical interventions to correct these manifestations. Few studies that have looked at the outcomes of cardiothoracic surgeries in APLS patients have reported high rates of perioperative mortality and thromboembolic events. Our goal was to examine the outcomes of adult APLS patients undergoing coronary artery bypass surgery (CABG) and/or valvular surgery. We also wanted to determine whether aggressive anticoagulation therapy could prevent life threatening thromboembolic complications in these patients. We retrospectively reviewed medical records of nine patients with primary APLS undergoing cardiothoracic surgery between 1985 and 2005 at our institution. Patient demographics, operative procedures and one-year clinical outcomes were obtained. Forty-five percent of our patients had more than three cardiovascular risk factors other than APLS. There were no mortalities in our case series. However, 89% of our patients developed major complications. Despite aggressive anticoagulation, 37.5% developed thromboembolic events including cerebrovascular accidents, myocardial infarctions and vena caval thrombosis. Other complications included heparin-induced thrombocytopenia, redo of CABG surgery and sepsis. Despite aggressive anticoagulation and lack of significant pre-operative co-morbidities, APLS patients undergoing cardiothoracic surgery appear to have high rates of post-operative clinical events.

The Role of Angina Pectoris in Chronic Pain After Coronary Artery Bypass Graft Surgery

Visceral nociception readily sensitizes the central nervous system, causing referred somatic pain and hyperalgesia via somato-visceral convergence. Hyperalgesia in the perioperative period may increase vulnerability to subsequent development of chronic pain. The study aim is to investigate the role of angina pectoris, an ischemic visceral pain, in long-term pain after coronary artery bypass surgery (CABG). We sent questionnaires to 369 patients who underwent CABG surgery in 2003. Questions were asked about angina pectoris and other pain in the period before surgery, the first week postoperatively (= acute pain), and the period after 3 months after surgery (= chronic pain). We obtained results from 256 patients (response rate = 69%). The point prevalence of chronic pain after CABG was 27% after a mean follow-up of 16 months (SD +/- 3 months). Patients with chronic pain after CABG had more angina pectoris than those without chronic pain: Before surgery (P = .07), early on postoperatively (P = .004), and more than 3 months after surgery (P = .000004). We found cumulative prevalences of chronic pain after CABG at 3 months of 39%, and of 32% after 6 months. Other predictive factors for chronic pain after CABG were acute postoperative pain (P = .00002) and younger age (P = .002). Angina pectoris is associated with chronic pain after CABG surgery. Other predictive factors include acute postoperative pain and younger age. The influence of postoperative angina pectoris for chronic pain after CABG surgery has not been described in the literature to date. Visceral nociception may play an important role in the development of chronic pain after surgery and should be taken into account in future studies.

Endoscopic vein harvesting in coronary artery bypass surgery

BACKGROUND: Leg wound complications and infections after harvesting of the greater saphenous vein (GSV) in coronary artery bypass surgery (CABG) represent a serious source of patient morbidity. Especially, in patients with obesity, diabetes and peripheral vascular disease, severe wound complications with increased pain occur more often. METHODS: Our aim was to evaluate the feasibility and the results of the endoscopic saphenous vein harvesting. From October 2002 until November 2005, in 63 patients with coronary artery disease, scheduled for elective CABG surgery, endoscopic vein harvesting (EVH) was performed using the Guidant VasoView® System. We investigated harvesting time and preparation time for the vein, intraoperative complications and conversion to traditional open harvesting, quality of the harvested vein including number of repairs needed, flow rates of the bypass grafts and postoperative wound related complications. RESULTS: The mean harvesting time was 37.5 min (19–72 min). Four patients had to be converted to the open harvesting technique because of bleeding and massive build up of fatty tissue inside the preparation tunnel. The quality of the harvested veins was assessed with a score of 1.4 on a scale ranging from 1 to 5. Side branches were either ligated or clipped. Small holes tears not suitable for tying were repaired with a prolene suture. The mean number of repairs was 1.4. In one patient, the wall of the endoscopically harvested vein was too thin and varicose, so that the vein was not suited to be used as a bypass graft. In 17 patients (29%) the EVH vein was needed for only one graft, in 37 patients (64%) the harvested vein was used for 2 grafts, and in 4 patients (7%) for 3 grafts. The mean flow rate of the EVH grafts was 50 ml/min (10–159 ml/min). Postoperatively, 22 patients (37%) had hematomas along the course of the preparation tunnel. These hematomas, however, had diminished at the time of discharge. There were no leg wound complications or infections. CONCLUSIONS: The advantages of EVH are the reduced trauma to the leg and the painless and faster mobilization of the patients. The harvesting time is acceptable despite a learning curve. The operative time is not prolonged. The visualisation of the EVH system is excellent and the handling can be adopted easily. The quality of the endoscopically harvested veins is equal to an open harvest technique, with the advantages of less postoperative pain and a better cosmetic result. The conversion rate is low (4 of 63). Postoperative wound complications are not to be expected.

Does coronary artery bypass surgery affect metoprolol bioavailability

beta-blockers are commonly administered in patients with coronary artery bypass surgery (CABG). Despite this therapy, however, the incidence of postoperative atrial fibrillation (AF) is high (9-19%), and it is unknown why the beta-blockers do not reduce the incidence of AF more efficiently. In this pharmacokinetics study, in which the patients acted as their own controls, we have evaluated the bioavailability of perioperative metoprolol tablets in CABG surgery patients. Twelve male patients, aged 45-64 years, scheduled for CABG surgery were administered an initial 50 mg metoprolol tartrate tablet orally on the morning of the preoperative day and thereafter at 12-h intervals. Regular blood samples were collected up to 12 h after the first administration of the drug on the preoperative day as well on the first and third postoperative days. The plasma concentration for metoprolol was analyzed (limit of quantification = 0.001 mg/L) using liquid chromatography-tandem mass spectrometry. The bioavailability of the metoprolol was significantly less on the first postoperative day, with AUC(0-12) values ranging from 0.7 to 17.1 (median: 7.2) mg min/L, than on the preoperative day, with AUC(0-12) values of 5.1-26.7 (12.6) mg min/L; however, it returned to the preoperative values on the third postoperative day, with AUC(0-12) values of 3.5-25.2 (15.2) mg min/L. Similar changes were observed in C(max) values: preoperative C(max) ranged between 0.026 and 0.123 (0.060) mg/L, on the first postoperative day, the C(max) ranged between 0.003 and 0.093 (0.025) mg/L, and on the third postoperative day, the C(max) ranged between 0.009 and 0.136 (0.061) mg/L. There was no correlation between the pharmacokinetic parameters and patient characteristics, but both the preoperative C(max) and C(60) correlated significantly with the postoperative C(max) (Pearson correlation coefficient: 0.61-0.72). One patient with one of the lowest rates and extent of metoprolol absorption developed AF. This study indicates that the bioavailability of metoprolol is markedly reduced when administered in tablet form during the early phase after CABG.

Thrombogenic Side-Effects of Recombinant Factor VIIa after use in Coronary Artery Bypass Surgery

Recombinant activated factor VII (rFVIIa) has been used 'off licence' to successfully treat bleeding and reduce transfusion requirements in complex cardiac surgery. However; concerns over thrombogenic side-effects have limited but not excluded its use in patients undergoing coronary artery bypass surgery (CABG). We present two cases of CABG (one 'on pump' and one 'off pump') which were complicated by intraoperative aortic dissection and severe bleeding. In both cases the bleeding was successfully treated with rFVIIa. However the first case suffered from severe postoperative arrhythmias, myocardial infarction, cardiac arrest and worsening left ventricular dysfunction, suggesting graft patency may have been impaired, whereas the second case remained symptom-free suggesting graft patency was unaffected by the use of rFVIIa. If rFVIIa is needed to treat bleeding during CABG surgery, it may be more appropriate to administer smaller, repeated doses to minimize the risk of thrombosis and early graft failure.

Predictors and Outcomes of Extended Intensive Care Unit Length of Stay in Patients Undergoing Coronary Artery Bypass Graft Surgery

To assess risk predictors of increased intensive care unit (ICU) length of stay in patients undergoing isolated coronary artery bypass surgery (CABG) and assess outcomes associated with increased ICU length of stay. We conducted a nested case-control study from a 9-year hospitalization cohort with prospective data collection (N = 9869). Cases were CABG patients with ICU greater than or equal to 168 hours (N = 236) and controls were CABG patients with an ICU stay of less than 168 hours (N = 708). We examined 15 risk factors and 11 outcomes. Nine risk factors proved significant in predicting an increased ICU length of stay. Cases were more likely to be older, with an increased pump time, and a lower body surface area. Cases tended to be female, with COPD, hypertension, and undergoing an urgent surgical procedure. Controls tended to have hypercholesterolemia and abnormal left ventricular hypertrophy. There was no significant difference between the cases and controls for the remaining six risk factors. Five of the nine significant predictors correlated with four predictors: age, urgent surgical procedure, pump time, and chronic obstructive pulmonary disorder (COPD). Using logistic regression analysis, we found that patients undergoing CABG had an increased ICU length of stay if they were older than 70 years (OR 2.59, 95% CI 1.86 to 3.62), with longer pump time (OR 2.45, 95% CI 1.75 to 3.44), had COPD (OR 2.04, 95% CI 1.36 to 3.05), and had an urgent surgical procedure (OR 1.59, 95% CI 1.12 to 2.26). Patients with an extended ICU length of stay were also found to experience 11 additional negative outcomes. In patients undergoing CABG surgery an increased age, increased pump time, COPD, and urgent surgical procedure significantly increased the risk of an increased ICU length of stay. Patients with an increased ICU length of stay also experienced more negative outcomes.

Predictors and outcomes of gastrointestinal complications in patients undergoing coronary artery bypass graft surgery: a prospective, nested case-control study.

The aim of this study was to assess risk factors and outcomes of gastrointestinal (GI) complications in patients undergoing coronary artery bypass surgery (CABG). We conducted a nested case-control study from a 9-year hospitalization cohort (n = 7,345) in which data were collected prospectively. Patients developed GI complications (n = 66) and controls did not (n = 330). Cases were matched to controls 1:5 on type of surgery. We examined 16 risk factors and 14 outcomes. Five risk factors proved significant in predicting GI complications. Patients were more likely to be older than age 70, to be on dialysis, to have left ventricular hypertrophy, and to be on anticoagulants; the procedure was also more likely to be urgent. There was no significant difference between the cases and controls for the remaining 11 risk factors. We also computed correlation coefficients among the significant variables; using regression analysis, we found that patients undergoing CABG had a threefold increase in the risk of GI complications if they were older than age 70 (odds ratio [OR] 1.06, 95% CI 1.03 to 0.97), if they were on dialysis (OR 1.87, 95% CI 1.98 to 1.22), and if their procedure was urgent (OR 1.91, 95% CI 1.07 to 3.4). Eleven outcomes proved significant. Patients with GI complications ran a greater risk of mortality; required more additional procedures; suffered arrhythmia that required treatment; and were more likely to have neurologic, pulmonary, renal, and sternal wound complications. They also had greater length of hospitalization, intensive care unit length of hospitalization, ventilator time, and postoperative creatine phosphokinase levels. In patients undergoing CABG surgery, urgency of the procedure, age greater than 70 years, and dialysis all significantly increased the risk of a GI complication. Patients with GI complications also experienced more negative outcomes.

Adipose tissue in myocardial infarction

Introduction The histologic evolution of myocardial infarction (MI) has been studied in some detail. However, there is little mention of the presence of adipose tissue in healed MI(HMI). Ninety-one hearts explanted during 1997–2001 were examined to determine the extent of adipose tissue within HMI. Methods The medical records, surgical pathology reports, and all histologic sections of the explanted heart, from patients undergoing heart transplantation for ischemic heart disease, were reviewed. Adipose tissue within the areas of HMI was quantified. The location of the HMI, the age and gender of the patient, age of HMI, and whether the patient was treated with coronary artery bypass surgery (CABG) were noted. Results Of the 91 hearts examined, 168 HMIs were identified; 141 (84%) contained some mature fat within the HMI. Adipose tissue increased with increasing age, in males, and in those patients who had CABG surgery. The amount of adipose tissue was not related to the location or age of the HMI. Conclusion Adipose tissue is a prevalent histological finding in HMIs. The pathogenesis of adipose tissue is unknown, but may be influenced by current medical therapy for ischemic heart disease, thus explaining why adipose tissue in HMIs was not reported until 1997. The presence of fat supports the speculation that a regenerative cell, or multipotent stem cell, exists within the heart, and under the influence of microenvironmental or therapeutic factors can differentiate into fat, other mesenchymal tissues, and potentially even myocardium.

ICU readmission after cardiac surgery.

The increasing cost of intensive care unit (ICU) care and limited resources lead us to evaluate predictors of ICU readmission in a large group of patients undergoing coronary artery bypass surgery (CABG) at one institution. Two thousand one hundred and seventeen consecutive patients undergoing CABG surgery between January 1999 and August 2001 were reviewed retrospectively. The reasons for readmission were determined by reviewing the physician's progress notes, the nurse's progress notes and the discharge summary. A total of 75 patients were readmitted to ICU during the study period for a readmission rate of 3.6%. Eight of these were readmitted a second time, and three a third time, for a total of 86 readmissions. Forty-seven patients died, for a mortality of 2% among patients that were not readmitted to the ICU, compared to 17% among those who were readmitted (P<0.0001). Median hospital length of stay was 6 days for patients not readmitted and 23 days for those readmitted (P<0.0001). The most common reason for readmission was respiratory failure, accounting for 47% of readmissions (n=40). Multivariate analysis using a stepwise logistic regression analysis revealed that preoperative renal failure (odds ratio 2.13; CI 1.03-4.41) and prolonged mechanical ventilation of >24 h (odds ratio 10.52; CI 6.18-17.91) were the only independent predictors for readmission to the ICU after CABG. Identification of patients that have preoperative renal failure or that required initial ventilation for more than 24 h after CABG may help to identify patients at risk of ICU readmission. Preemptive strategies designed to optimize these high-risk patients may improve outcomes.

Surgical revascularization of the myocardium

It has been 45 years ago when Longmire (1958.) used internal thoracic artery (ITA) for the first time in coronary artery bypass surgery (CABG). In this review, we are presenting novel surgical approaches in CABG surgery. We have also been summarized the best of knowledge, up to date, regarding histology, pharmacology and pathophysiology of conduits (VSM, ITA and alternative venous and arterial grafts) which have been used in CABG surgery, as well as factors influence on its short and long-term patency.

Postoperative ventricular function and cardiac enzymes after on-pump versus off-pump CABG surgery

It is not known whether the extent and time course of myocardial dysfunction and recovery differ between patients undergoing off-pump coronary artery bypass surgery (CABG) and on-pump CABG. We conducted a nonrandomized pilot study to assess myocardial stunning and the time course of functional recovery in patients undergoing off- and on-pump CABG. Ventricular function was assessed using myocardial contrast echocardiography because contrast-enhanced images provide better endocardial border definition1 and patients who have undergone cardiac surgery generally have limited acoustic windows after operation.

Editorial: Atrial Fibrillation After Coronary Artery Bypass Grafting

Atrial fibrillation (AF) after coronary artery bypass surgery (CABG) is the most common sustained arrhythmia and the most common complication after CABG and consequently is a drain on hospital resources. Efforts to reduce the incidence of AF and the associated increased length of stay would result in substantial cost savings and decrease patient morbidity. 1 The incidence varies depending on the type of patient population involved. Age has been identified as the major independent predictor of post operative AF. Increasing age of patients accounts for the higher incidence of postoperative AF in recent years.2 Incidence of AF after CABG far exceeds the reported prevalence in the general population and in patients with coronary artery disease (CAD).3 Similarly, it is significantly higher than the reported incidence of AF after major noncardiac surgery regardless of CAD status.4 The pathophysiological mechanisms responsible for the high incidence of AF after CABG surgery is unclear. Some of the mechanisms suggested are sblocker withdrawal, the use of cardiopulmonary bypass, inadequate atrial protection, and overmanipulation of the right atrium1 Amiodarone has been increasingly used as an antiarrhythmic agent to prevent the occurrence of AF after cardiac surgery.5 Amiodarone seems to act through a prolongation of atrial refractoriness. However, the precise mechanism of action is not well understood because amiodarone does not predictably lengthen atrial repolarization acutely.6,7 It has been hypothesized that its effect may stem from its nonspecific antiadrenergic effect, its class I actions, or other actions not yet identified.6 Moreover, amiodarone has coronary vasodilatory effects8 that may benefit cardiac surgical patients. The response to amiodarone therapy for arrhythmia was found to be delayed in diabetic patients compared with that in non-diabetic patients undergoing coronary artery bypass grafting operation.9 This data from the current issue of the journal suggest a less pronounced sympatholytic effect of amiodarone treatment in diabetic patients undergoing CABG when compared with nondiabetic patients undergoing the same operation. Lervasi et al10 has demonstrated that the use of intravenous amiodarone loading dose in diabetic patients with cardiac arrhythmia has a later decrease in heart rate (after 4 days from the initiation of treatment) with a later antiarrhythmic positive response when compared with the results with nondiabetic arrhythmic patients who have a very early decrease in heart rate (within 4 hours of begining of treatment). Nondiabetic patients also have an early antiarrhythmic positive response (on average within 7 hours). Both these studies implicate the antiadrenergic effect of amiodarone in its antiarrhythmic action and the blunting of this response in diabetics, possibly due to autonomic dysfunction. Beta-blockers are useful for prevention of atrial fibrillation following cardiothoracic surgery, in which atrial fibrillation occurs in approximately 30% of patients11. The benefit of beta-blockade is greatest in patients who have received betablockers previously, although a reduction in atrial fibrillation is seen also in patients not previously on beta-blockers. The efficacy of beta-blockers in this situation is probably due to the elevated sympathetic tone present postoperatively. Betablockers protect against adrenergically mediated shortening of the action potential duration that is thought to help precipitate and maintain atrial fibrillation12. Another potential mechanism for preventing atrial fibrillation is suppression of pulmonary vein ectopy that triggers atrial fibrillation13. The use of magnesium in the preoperative and early postoperative periods has also been shown to be effective in reducing the incidence of AF after coronary artery bypass Editorial: Atrial Fibrillation After Coronary Artery Bypass Grafting 2 of 3 grafting.14 Postoperative AF occurred in 2 (2%) patients in the magnesium group and in 21 (21%) patients in the control group (p < 0.001). Patients in the magnesium group received 6 mmol MgSO4 infusion in 100 mL 0.9% NaCl solution (25 mL/h) the day before surgery, just after cardiopulmonary bypass, and once daily for 4 days after surgery. In a recent report, a novel intraoperative treatment strategy of both mechanical (leukocyte filtration) and pharmacological (aprotinin) intervention appears to markedly reduce the incidence of postcardiopulmonary bypass atrial fibrillation15 The proposed mechanism is that leukocyte depletion by filtration with the addition of aprotinin would reduce the systemic inflammatory effects of bypass and reduce the incidence of atrial fibrillation. The beneficial effects of the reduction of atrial fibrillation include reduced risk of embolism and lesser incidence of ischemia in the heart, lung and brain. In addition, there is a decrease in length of hospital stay, recovery time and overall cost. Hence more research into the mechanisms and treatment modalities of this most common postoperative arrhythmia is needed.