Diabetes in pregnancy may differentially affect neonatal outcomes for twins and singletons.

AIM: We tested the hypothesis that diabetes in pregnancy may differentially affect neonatal outcomes in twin vs. singleton pregnancies. METHODS: In a retrospective cohort analysis of twins (n = 422 068) and singletons (n = 14 298 367) born in the USA from 1998 to 2001, we evaluated the adjusted odds ratios of adverse neonatal outcomes comparing diabetic vs. non-diabetic pregnancies, controlling for maternal characteristics. Primary outcomes include macrosomia (birthweight for gestational age > 90th percentile), congenital anomalies, low 5-min Apgar score (< 4) and neonatal death. RESULTS: Diabetes in pregnancy was associated with a similarly increased risk of congenital anomalies (adjusted odds ratios 1.52 vs. 1.59) and smaller increased risks of preterm birth (adjusted odds ratios 1.27 vs. 1.49) and macrosomia (adjusted odds ratios 1.38 vs. 2.03) in twins vs. singletons, but reduced risks of low 5-min Apgar score (adjusted odds ratio 0.74) and neonatal death (adjusted odds ratio 0.76) in twins but not singletons. CONCLUSIONS: Diabetes in pregnancy may differentially affect neonatal outcomes in twins and singletons, indicating a need for further studies to differentiate the effects by clinical subtypes of diabetes in pregnancy, and to consider/evaluate differential clinical management protocols of diabetes in multiple vs. singleton pregnancies.

Optimal birth weight percentile cut-offs in defining small- or large-for-gestational-age.

AIMS: It remains questionable what birth weight for gestational age percentile cut-offs should be used in defining clinically important poor or excessive foetal growth. We aimed to evaluate the optimal birth weight percentile cut-offs for defining small- or large-for-gestational-age (SGA or LGA). METHODS: In a birth cohort-based analysis of 17 979 120 non-malformation singleton live births, U.S. 1995-2001, we assessed the optimal birth weight percentile cut-offs for defining SGA and LGA. The 25th-75th percentile group served as the reference. Primary outcomes are the risk ratios (RR) of neonatal death and low 5-min Apgar score (<4) comparing SGA or LGA versus the reference group. More than 2-fold risk elevations were considered clinically significant. RESULTS: The 15th birth weight cut-off already identified SGA infants at more than 2-fold risk of neonatal death at pre-term, term or post-term, except for extremely pre-term births <28 weeks (continuous risk reductions over increasing birth weight percentiles). LGA was associated with a reduced risk of low 5-min Apgar score at pre-term, but an elevated risk at term and post-term. The 97th cut-off identified LGA infants at 2-fold risk of low 5-min Apgar at term. CONCLUSION: The commonly used 10th and 90th birth weight percentile cut-offs for defining SGA and LGA respectively seem largely arbitrary. The 15th and 97th percentiles may be the optimal cut-offs to define SGA and LGA respectively.

Molecular detection of cancer cells in bone marrow and peripheral blood of patients with operable breast cancer. Comparison of CK19, MUC1 and CEA using RT-PCR.

We have compared three different RT-PCR procedures to measure cytokeratin 19 (CK19), carcinoembryonic antigen (CEA) and mucin MUC1 gene expression in order to determine their diagnostic value in detecting tumour cells in bone marrow aspirates of patients with operable breast cancer. In an experimental model, the best sensitivity was observed for CK19 and MUC1 RT-PCR assays, although only the CEA and CK19 assays showed good specificity. The study of 42 patients showed that a 'CK19 positive/CEA positive' RT-PCR assay in bone marrow correlated positively with a positive axillary lymph node status (N(0) versus N(1-3), P<0.05). Both assays were also positive in 17% of node negative patients. RT-PCR assays were more sensitive in bone marrow than in peripheral blood. Our results suggest that CK19 and CEA RT-PCR assays are powerful methods for detecting disseminated breast cancer cells. A larger study with long-term follow-up is required in order to clarify their clinical usefulness.

Gastrointestinal complications after coronary artery bypass grafting.

Clinical variables were studied in 3129 patients undergoing coronary artery bypass grafting to identify patients at risk of abdominal complications and common etiologic factors in the development of such complications. Seventy-three gastrointestinal complications occurred (2.3%), with an overall mortality rate of 16.4% compared with a mortality rate of 3.4% for all patients undergoing bypass grafting (p < 0.001). Cholecystitis and intestinal ischemia were the most frequently encountered complications. Multivariate analysis demonstrated that preoperative hypertension, New York Heart Association classes III and IV, preoperative left ventricular ejection fraction less than 40%, age greater than 70 years, reoperation, and urgent operation as independently and significantly associated with gastrointestinal complications. In contradiction to previous reports, no significant correlation existed between gastrointestinal complications and cardiopulmonary bypass time, 99.8 +/- 35.8 versus 101.2 +/- 39.8 minutes. Perioperative myocardial infarction and immediate postoperative hypotension with low cardiac output necessitating substantial inotropic pharmacologic support or intraaortic balloon pumping were significantly more prevalent in patients who had gastrointestinal complications (all p < 0.001). Furthermore, multivariate analysis revealed that postoperative low cardiac output was a significant, independent predictor in the development of gastrointestinal complications of any kind after coronary artery bypass grafting. Postoperative splanchnic hypoperfusion could therefore be a common etiologic factor.

Economic impact of preoperative intraaortic balloon pump therapy in high-risk coronary patients.

BACKGROUND: The efficacy of preoperative intraaortic balloon pump therapy in high-risk coronary patients has been demonstrated earlier. METHODS: This study investigates the economic aspect by a detailed cost analysis of pooled information from two previously published randomized studies and 144 consecutive low-risk coronary artery bypass graft operations. Costs for patients receiving preoperative intraaortic balloon pump therapy before aortic cross-clamping (n = 62) were compared to those in a control group (n = 50). Detailed cost analysis was based on data provided by the hospital finance department. RESULTS: The total hospital costs were as follows: low-risk coronary artery bypass graft operations cost 35,335+/-1,694 Swiss francs ($23,400+/-$1,121); high-risk coronary artery bypass graft without preoperative intraaortic balloon pump therapy cost 65,892+/-31,719 Swiss francs ($43,637+/-$21,006); and high risk coronary artery bypass graft with preoperative intraaortic balloon pump therapy cost 41,948+/-10,379 Swiss francs ($27,780+/-$6,874) (p = 0.0015). There were no significant differences in average cost among the preoperative intraaortic balloon pump therapy subgroups. CONCLUSIONS: Preoperative intraaortic balloon pump therapy in high risk coronary patients is significantly cost-beneficial, With an average saving of 24,000 Swiss francs ($16,000) on the total hospital cost, a 36% cost reduction.

Plateletpheresis before redo CABG diminishes excessive blood transfusion.

BACKGROUND: Blood conservation remains an important element for patients undergoing cardiac operations with cardiopulmonary bypass. Preoperative platelet-rich plasma (PRP) harvest is an autologous blood conservation method. The efficacy of preoperative PRP harvest and post-cardiopulmonary bypass reinfusion on postoperative bleeding and need for postoperative blood transfusion was evaluated in patients undergoing redo coronary artery bypass grafting in a prospective, randomized manner. METHODS: All adult patients admitted for redo coronary artery bypass grafting entered into the study. The PRP harvest aim was 20% or more of the total estimated circulating platelets. Immediately preoperatively three sequestration cycles were performed. The PRP was reinfused after weaning from cardiopulmonary bypass. One hundred seven parameters/patient were recorded. There were 20 patients in the RPR group and 20 controls (without PRP harvest). RESULTS: Patient characteristics, operative data, and preoperative hematologic parameters did not differ between the groups. In the PRP group, the mean platelet count in the PRP was 864 +/- 139 x 10(3)/microL, and the platelet yield was 27% +/- 5% (range, 20% to 37%). The average total chest tube blood loss was 423 mL (PRP) compared with 1,462 mL (controls; p < 0.001). Fourteen patients in the control group required blood transfusions postoperatively compared with only 1 patient in the PRP group (p < 0.001). Postoperative fluid requirements were also significantly greater in the control group (p < 0.001). Postextubation gas exchange was significantly better in the PRP group compared with controls (p < 0.01). Postoperative ventilation time and intensive care stay were significantly shorter in patients in the PRP group. CONCLUSIONS: A preoperative PRP harvest of 20% or more of the total platelets and reinfusion of the PRP after cardiopulmonary bypass resulted in significantly less postoperative blood loss and decreased fluid and blood transfusion requirements compared with controls. Postextubation gas exchange, ventilation time, and time required in the intensive care unit were also better, and the method was found cost-effective.

Preoperative intraaortic balloon pump enhances cardiac performance and improves the outcome of redo CABG.

BACKGROUND: Reoperative coronary artery bypass grafting (redo CABG) is associated with an increased operative risk compared with primary CABG. Because the hospital mortality in redo CABG is known to be influenced by poor left ventricular function (left ventricular ejection fraction < or = 0.40), unstable angina, and left main stem stenosis greater than or equal to 70%, a preoperative intraaortic balloon pump (IABP) support could be beneficial to improve the outcome in high-risk redo CABG. METHODS: Between June 1994 and October 1996, 48 high-risk patients underwent redo CABG and were randomized into the following groups: group 1 (24 patients) who received preoperative IABP treatment on average 2 hours before cardiopulmonary bypass, and group 2 (24 patients) who received no preoperative IABP and served as controls. Mean age was 65 years and 90% (43 patients) were men. Forty-one patients had preoperative left ventricular ejection fraction less than or equal to 0.40 (85%), 38% (18 patients) had left main stem stenosis greater than or equal to 70%, and 54% (26 patients) had unstable angina preoperatively. Preoperative patient characteristics did not differ between the groups. RESULTS: The time on cardiopulmonary bypass was shorter in group 1, 86 versus 110 minutes (p = 0.006). There were no hospital deaths in group 1, but four deaths occurred in the control group (p = 0.049). Cardiac index rose significantly preoperatively after introduction of the IABP in group 1. Cardiac index was significantly higher postoperatively in group 1 compared with group 2 and remained significantly higher during the first 24 hours after cardiopulmonary bypass. Significantly fewer patients in the IABP group had postoperative low cardiac output (4 versus 13 patients). Nine patients in group 2 required IABP support postoperatively for 4.1 +/- 1.7 days. Only 2 patients in group 1 needed IABP postoperatively, and their IABPs were successfully removed on the first postoperative day. The preoperative IABP-supported patients had a shorter intensive care unit stay, 2.4 +/- 0.8 days compared with group 2, 4.5 +/- 2.2 days (p = 0.007), as well as a shorter hospital stay. The preoperative IABP treatment was found to be cost-effective. CONCLUSIONS: Preoperative treatment with IABP in high-risk redo CABG patients is an effective modality to prepare these patients to have their myocardial revascularization in an as nonischemic situation as possible, which resulted in a significantly lower hospital mortality, fewer instances of postoperative low cardiac output, and shorter stays in both the intensive care unit and the hospital.

Optimal timing of preoperative intraaortic balloon pump support in high-risk coronary patients.

BACKGROUND: Beneficial effects of preoperative intraaortic balloon pump (IABP) treatment, on outcome and cost, in high-risk patients who have coronary artery bypass grafting have been demonstrated. We conducted a prospective, randomized study to determine the optimal timing for preoperative IABP support in a cohort of high-risk patients. METHODS: Sixty consecutive high-risk patients who had coronary artery bypass grafting (presenting with two or more of the following criteria: left ventricular ejection fraction less than 0.30, unstable angina, reoperation, or left main stenosis greater than 70%) entered the study. Thirty patients did not receive preoperative IABP (controls), 30 patients had preoperative IABP therapy starting 2 hours (T2), 12 hours (T12), or 24 hours (T24), by random assignment, before the operation. Fifty patients had preoperative left ventricular ejection fraction mean, less than 0.30 (less than 0.26+/-0.08), (n = 40) unstable angina, 28% (n = 17) left main stenosis, and 32% (n = 19) were reoperations. RESULTS: Cardiopulmonary bypass was shorter in the IABP groups. There was one death in the IABP group and six in the control group. The complication rate for IABP was 8.3% (n = 5) without group differences. Cardiac index was significantly higher postoperatively (p<0.001) in patients with preoperative IABP treatment compared with controls. There were no significant differences between the three IABP subgroups at any time. The incidence of postoperative low cardiac output was significantly lower in the IABP groups (p<0.001). Intubation time, length of stay in the intensive care unit and the hospital was shorter in the IABP groups (p = 0.211, p<0.001, and p = 0.002, respectively). There were no differences between the IABP subgroups in any of the studied variables. CONCLUSIONS: The beneficial effect of preoperative IABP in high-risk patients who have coronary artery bypass grafting was confirmed. There were no differences in outcome between the subgroups; therefore, at 2 hours preoperatively, IABP therapy can be started.

The influence of age on the results of reoperative coronary artery bypass grafting.

BACKGROUND: With a steady increase in the number of elderly patients requiring coronary artery bypass grafting (CABG), a larger portion of elderly patients will also become candidates for reoperative CABG. Scepticism still exists as to whether this operation is justified in older patients. The purpose of this study was to examine the effect of increasing age on the outcome after reoperative CABG. METHODS: Between January 1, 1990 and June 30, 1996 563 patients underwent isolated reoperative CABG, and were included in this retrospective analysis. Patients who had combined procedures were excluded. The patients were divided by age into two groups: those aged 69 years or less (n = 507), and those older than 70 years (n = 56). Hospital mortality and morbidity for each group was compared. Medium-term survival for each group was compared with that of their age-matched population derived from Swiss life tables. RESULTS: The patients aged 70 years and older had a higher New York Health Association functional class, and more patients had unstable angina requiring urgent surgery than did the younger patients. The elderly also showed an over-representation of diabetes and multifocal vascular disease (generalized arteriosclerotic disease), and there was a higher number of patients with triple-vessel disease and left stenosis (> or = 70%) in this group. Patients aged 70 years and older received fewer distal anastomoses (3.0 versus 3.6; P < 0.01), and had a longer cardiopulmonary bypass time compared with the younger patients, but the ischemia time was similar in both groups. Hospital mortality was higher in patients older than 70 years (7.1 versus 17.9%). There was an increased frequency of postoperative low cardiac output and a higher incidence of gastrointestinal complications and transient renal failure amongst the elderly patients (> or = 70 years). Despite a higher hospital mortality rate and slightly increased morbidity the 5-year survival was excellent, and comparable with the age-matched population in both groups [89.6% (< 70 years) and 76.2% (> or = 70 years)]. The cardiac event-free survival was 79.8% (< 70 years), and 69.9% (> or = 70 years) after 5 years. CONCLUSION: An acceptable early mortality and long-term survival together with good functional long-term results support the justification of reoperative CABG in older patients, at least up to the age of 80 years.

Extensive endarterectomy of the left anterior descending coronary artery combined with coronary artery bypass grafting.

BACKGROUND: Complete revascularization of a diffusely diseased left anterior descending (LAD) coronary artery can be accomplished by extensive endarterectomy in conjunction with coronary artery bypass grafting (CABG). The present study was designed to assess the safety of the procedure, and which techniques lead to the best short- and long-term results. METHODS: Between January 1990 and October 1994 106 patients underwent extensive open endarterectomy of the LAD coronary artery combined with CABG at our institution. This group constituted 4.9% of all patients undergoing CABG during this period. The mean age of those studied was 64.4 +/- 9.2 years and 92% were male. In 22 patients (21%) the procedure was a repeat CABG and 12% had had percutaneous transluminal coronary angioplasty prior to the operation. Ninety-one per cent of the patients were in Canadian Cardiovascular Society (CCS) angina class 3 or 4, 91% had three-vessel disease and 36% had unstable angina at the time of surgery. The mean preoperative left ventricular ejection fraction was 53.6 +/- 14.9% (range, 15-80%). The internal mammary artery (IMA) was used to bypass the LAD coronary artery in 40 patients (38%) and a saphenous vein graft (SVG) was used in 66 patients. In 25 of the IMA bypass group an additional venous patch was used (IMA+P). RESULTS: The overall mortality rate was 9.4% (10 patients), including seven immediate postoperative deaths. When the IMA was used as a conduit the mortality rate was only 5.0%. There were seven (6.6%) postoperative non-fatal myocardial infarctions. There was a low incidence of other postoperative complications, similar to that following CABG without endarterectomy performed during the same period. Multivariate analysis identified emergency operation, two-vessel endarterectomy and female sex as independent risk factors for mortality. Upon follow-up study of 94 hospital survivors (98%), at a mean of 26.5 months (range, 1-48 months), all endarterectomy patients were in CCS class 1 or 2. Seventy-eight patients (83%) had an excellent postoperative exercise tolerance and the left ventricular function was preserved. The 4-year survival rates were 88% and 96% and the cardiac event-free survival rates were 74% and 87% in the SVG and IMA groups respectively. CONCLUSIONS: Complete revascularization of the diffusely diseased LAD coronary artery can be accomplished by adjunctive open endarterectomy with a degree of operative risk (mortality 9% and incidence of non-fatal myocardial infarction 7%). The immediate and medium-term results are improved when the IMA is used as a conduit, with or without additional venous patch. Independent risk factors for mortality were two-vessel endarterectomy, female sex and emergency operation. The long-term results revealed an overall survival rate of 92% and a cardiac event-free survival rate of 79% at 4 years, as well as excellent functional results.

How safe is coronary bypass surgery in the elderly patient? Analysis of 111 patients aged 75 years or more and 2939 patients younger than 75 years undergoing coronary artery bypass grafting in a private hospital.

AIM AND METHODS: Data from patients younger than 75 years (group I, n = 2939) and patients aged 75 years or older (group II, n = 111) who underwent isolated coronary artery bypass grafting (CABG) during a 9-year period (January 1984 to April 1993) were analyzed to determine comparative risk factors for morbidity, early and late survival, and functional outcome. RESULTS: Traditional risk factors (hypertension, hyperlipidemia, diabetes mellitus, and smoking) were significantly more prevalent in group II. The number of patients in New York Heart Association (NYHA) functional classes 3 and 4 before surgery was also significantly higher in group II (P < 0.001), but emergency operations were equally distributed between the groups. Left main-stem stenosis was more frequent in group II patients (P < 0.01), while the number of vessels involved and pre-operative left ventricular function did not differ. Both groups underwent a mean of 4.5 grafts. Internal mammary grafts were placed in 48.4% (1422/2939) in group I and 19.8% (22/111) in group II (P < 0.001). The overall peri-operative mortality rate did not differ between the groups (2.9% for group I and 2.7% for group II). Non-fatal peri-operative myocardial infarction, ventricular arrhythmias, post-extracorporeal circulation disorientation, and temporary renal insufficiency were more prevalent in group II patients (all P < 0.05). Emergency operations and re-operative CABG increased the peri-operative mortality in both groups. The 3-year survival rate was 93% and the 3-year cardiac event-free rate was 88% for the group II patients. Most of the elderly patients (98%) were in NYHA functional classes 1 and 2 at the end of the follow-up. CONCLUSIONS: Even if elderly patients have a slightly higher postoperative morbidity than younger patients, and an increased mortality if operated upon in an emergency, long-term survival and freedom from cardiac events are excellent and justify the continued performance of CABG in patients aged 75 years of age or more.

Is reoperative coronary artery bypass grafting in patients with poor left ventricular ejection fractions < or = 25% worthwhile?

AIM: This study aimed to investigate whether patients with very low left ventricular ejection fractions (LVEF) should be accepted for reoperative coronary artery bypass grafting (CABG). STUDY POPULATION: Between January 1990 and December 1993, 1681 patients underwent primary CABG and 308 (15.5%) reoperative CABG. One hundred and eight patients (5.4%) had an LVEF < or = 25%, 91 patients for primary CAGB (group I) and 17 for CABG (group II). The mean age of the patients was 62 years. Sex distribution and preoperative risk factors did not differ. Urgent operations were more frequently necessary in group II (P < 0.01). Mitral regurgitation was present in 49% of the group I patients and 18% of the group II patients (P < 0.05). Pulmonary artery hypertension was observed in 24% of group I patients, but in only 6% in group II patients. The mean LVEF was 21% and left ventricular end-diastolic pressure 18 mmHg, without between-group differences. All patients had significant two- or three-vessel disease (stenosis > or = 70%). An average of 4.5 grafts per patient were performed. Mitral valve surgery was not performed in any of the patients. RESULTS: The postoperative mortality was significantly higher in reoperative CABG patients (group II; 23.5%) than in group I patients (12.1%; P < 0.05), whereas the incidence of non-fatal myocardial infarction did not differ. The incidence of postoperative complications did not differ between the groups, except for transient renal failure, more frequently encountered in group II (P < 0.05). After an average follow-up of 18 months, the New York Heart Association (NYHA) class and the LVEF were significantly improved in both groups (NYHA class from 3.5 to 1.8 and LVEF from 21% to 45%; P < 0.001). The mitral regurgitation had improved or completely disappeared at the end of follow-up in all patients in both groups. CONCLUSIONS: Our results suggest that patients with left ventricular ejection fraction < or = 25%, angina and significant two- or three-vessel coronary artery disease should not categorically be refused for reoperative CABG. Careful patient selection is necessary because of an increased operative risk.

Surgery of the ascending aorta. Analysis of risk factors and results of 30 operations in a private institution.

Replacement of the ascending aorta for aneurysm or dissection remains a complex challenge for cardiac surgeons. Between January 1984 and December 1993, 30 patients have had simultaneous resection of the ascending aorta and aortic valve replacement. Sixteen of them had composite graft replacement of the ascending aorta and the aortic valve with a modified Bentall's technique (Group I). Fourteen patients had supracoronary artery aortic resection and aortic valve replacement (Group II). The mean age was 50.1 +/- 15.3 years (range 23-76). There were 22 men and 8 women. Five patients (16.7%) had aortic dissection, six were operated on an emergency basis. Concomitant coronary artery disease was more frequently seen in Group II (5 patients) than in Group I (1 patient), p < 0.05. Other preoperative patient characteristics did not differ. The overall perioperative mortality was 16.7% (5/30), none of them due to technical complications during surgery. Four patients died in Group I and 1 in Group II (n.s.). Non-fatal myocardial infarction was diagnosed in 1 patient (Group I) and only one neurological complication occurred (Group I), while reexploration for bleeding was performed in 4 cases (13.3%). Four patients in Group I and two in Group II had postoperatively low cardiac output, two of them necessitating intraaortic balloon pump insertion. 43% of the patients had no perioperative complications. At the end of follow-up (n = 25), average 6 months (range 1-52 months), twenty-two survivors (22/25 or 88.0%) were in NYHA functional class 1. Simultaneous ascending aortic aneurysm repair and aortic valve replacement can be accomplished with an acceptable mortality and little morbidity.

Should a mild to moderate ischemic mitral valve regurgitation in patients with poor left ventricular function be repaired or not?

In recent years coronary artery bypass grafting (CABG) has been extended to include patients with very low left ventricular ejection fractions (LVEF), also frequently with co-existing mild to moderate mitral valve regurgitation (MR). The question is, should such a MR be corrected simultaneously with a myocardial revascularization or not? Between January 1989 and November 1994, 56 patients with preoperative LVEF < or = 25% and echocardiographic evidence of co-existing MR (Grade I: 41%, II: 46%, III: 13%) underwent primary CABG. None of them had simultaneous mitral valve surgery. Twenty-nine patients (52%) had a pulmonary artery pressure (PAP) > 40 mmHg. The mean preoperative LVEF was 17.9 +/- 4.6 (10-25), mean PAP 44.2 +/- 16.1 mmHg. An average of 4.5 +/- 1.5 grafts/patient were placed and five patients had simultaneous repair of a post-infarction left ventricular aneurysm. The overall mortality was 3.6% (2/56). Transient post-operative low cardiac output syndrome occurred in 16 patients (29%). Twenty-one patients (38%) had no postoperative complications at all. The 54 hospital survivors were followed up over a mean period of 12 months (3-36 months). There was one death (eight months postoperatively) and two graft occlusions, not requiring reoperation. At the end of the follow up echocardiography showed that 50 patients (93%) had no (31 patients) or only a very mild Grade I MR (19 patients). Four patients had Grade II MR, none of them requiring mitral valve surgery. All patients improved their NYHA functional class, from 3.4 +/- 0.8 to 1.9 +/- 0.7 and LVEF from 17.9 +/- 4.6 to 44.2 +/- 7.4 (p < 0.001). Coronary artery bypass grafting is a possible treatment for patients with very low LVEF, provided the patient has a two- or three-vessel disease with significant coronary artery stenosis (> 70%) and angina. Mortality and morbidity are low. Moderate co-existing MR (Grade I-III) seems to normalize after myocardial revascularization and should not be surgically corrected therefore at the primary operation.

Reoperative coronary artery bypass procedures: risk factors for early mortality and late survival.

OBJECTIVES: The number of coronary artery disease reoperations is increasing. The aim of this paper is to identify risk factors and evaluate the results of REDO coronary artery bypass grafting (CABG). MATERIAL: Between January 1984 and October 1994, 594 patients underwent REDO-CABG and 3157 underwent primary-CABG. The mean age was 62 years with 84% men. Hypertension, hyperlipidemia, insulin dependent diabetes, smoking and renal insufficiency were all more frequent in the REDO-group. A significantly higher number of patients undergoing REDO-CABG were in the Canadian Cardiovascular Society (CCS) angina class 3 and 4, had instable angina, had left main stem stenosis of greater than 70% and 3-vessel disease compared to those undergoing primary-CABG. The mean preoperative left ventricular function (LVEF) was 49.8 (REDO) vs. 58.2%, with a P value of less than 0.001. RESULTS: The overall postoperative mortality rate for REDO-operations was 9.6 (57/594) vs. 2.8% for primary-CABG. Patients with a reoperative interval of more than 1 year had an 8.9% mortality rate, compared to those reoperated less than 1 year after the initial CABG, where the mortality was 21% with a P value of less than 0.05. Postoperative low cardiac output syndrome, intraaortic balloon pump support, prolonged ventilatory support (> 24 h), hemorrhage and gastrointestinal complications were prominent features of the REDO-group (all P < 0.01). Urgent operation, CCS class 3 and 4, LVEF of less than 40%, generalized arteriosclerotic disease and advanced age (> 80 years) were independent risk factors for postoperative death in both groups. Preoperative renal insufficiency, diabetes and short interval from primary-CABG were added risk factors in the REDO-group. The 5-years survival rate after REDO-CABG was 89%, while the cardiac event-free survival rate was 79% and at 7 years 84 and 62%, respectively. CONCLUSIONS: Reoperative CABG is effective, but has an increased operative mortality and morbidity. The long-term results are encouraging. Unstable angina, poor preoperative left ventricular function, renal insufficiency, insulin dependant diabetes and an interval shorter than 1 year of the initial operation were independent riskfactors for mortality.

Open chest and delayed sternal closure after cardiac surgery.

OBJECTIVES: Open chest (OC) and subsequent delayed sternal closure (DSC) has been described as a useful method in the treatment of the severely impaired heart after cardiac surgery. METHODS: Prolonged open chest was used in 142 to 3373 adult cardiac operations (4.2%) between January 1987 and December 1993. The indications were: hemodynamic compromise (121), intractable bleeding (9) and arrhythmias (12). Delayed sternal closure was carried out in 123 of 142 patients at a mean of 2.0 +/- 1.4 days (range 0.5-8 days). Open chest and DSC were used proportionally more frequently after combined cardiac surgery (28/293, 9.6%) than after coronary artery bypass grafting (CABG) alone (108/2891, 3.7%) or valve operation (6/230, 2.6%). RESULTS: Ninety-seven of the 123 who had DSC (78.9%) survived and were discharged an average of 8.6 +/- 4.2 days after closure. Fourty-five patients died: 19 before DSC and 26 after this method. Mortality was related to indications for OC: when the indication was low cardiac output the mortality was 38.6%, for hemodynamic collapse on closure 0%, diffuse bleeding 33.3% and arrhythmias 27.3%. Delayed sternal closure in patients without intraaortic balloon pump support was more likely to be successful (mortality rate 4/25, 16.0% versus 35/76, 46.3%, P < 0.01). Superficial sternal wound infection occurred in 2 of 123 (1.6%) patients after DSC, mediastinitis in 1 (0.8%) and sternal dehiscence in 3 (2.4%) patients, which does not differ from a control population that had primary sternal closure. The follow-up of 97 survivors at an average of 28 +/- 4 months revealed an improvement of NYHA class by 1.4 +/- 0.4. There were 16 deaths (13 cardia-related) during the follow-up period and 3 redo CABG. One case of sternal osteomyelitis occurred without any other late sternal morbidity. CONCLUSIONS: This study shows that OC with DSC is a beneficial adjunct in the treatment of postoperatively impaired cardiac function, profuse hemorrhage and persistent arrhythmias. It can be performed without increased sternal morbidity. Long-term results are also encouraging.

Evaluation of preoperative intra-aortic balloon pump support in high risk coronary patients.

OBJECTIVE: The intra-aortic balloon pump (IABP) is an established additional support to pharmacological treatment of the failing heart after myocardial infarction, unstable angina and cardiac surgery. The effect of preoperative IABP in high risk patients was evaluated. METHODS: Between June 1994 and March 1996 all high risk patients for CABG (two or more of these criteria: Left ventricular ejection fraction (LVEF) < or = 40%, left main stem stenosis > or = 70%, REDO-CABG, unstable angina) were randomized into either of 3 groups: (1) IABP 1 day prior to surgery, (2) IABP 1-2 h prior to CPB and (3) no preoperative IABP, controls. EXCLUSION CRITERIA: cardiogenic shock preoperatively. Fifty-two patients have entered the study-group 1 (13 patients), group 2 (19 patients) and group 3 (20 patients). Preoperative patient characteristics and operative data revealed no group differences. There were 56% REDO's, unstable angina 59%, LVEF < or = 40%, 87% (34.0 +/- 11.6%) and left main stem stenosis in 35%. RESULTS: The CPB-time was shorter in groups 1 and 2 88.7 +/- 20.3 min than in group 3 105.5 +/- 26.8 min, P < 0.001, while ischemia time did not differ. Hospital mortality was higher in group 3, 25% vs. 6% (groups 1 and 2). Postoperative low cardiac output was seen in 12 patients (60%) in group 3 vs. 6 patients (19%) in groups 1 and 2, P < 0.05. Cardiac index increased significantly prior to CPB in groups 1 and 2. After CPB cardiac index was significantly higher in groups 1 and 2 compared to Group 3 and continued to increase. The IABP was removed after 3.1 +/- 1.0 days in group 3 vs. 1.3 +/- 0.6 days in groups 1 and 2, P < 0.001. In group 3, 11 patients required IABP postoperatively compared to only 4 patients in groups 1 and 2. ICU stay was shorter in groups 1 and 2--2.3 +/- 0.9 days vs. 3.5 +/- 1.1 days for group 3, P = 0.004. All patients received dopamin postoperatively, however in a lower dose in groups 1 and 2, 4.5 vs. 13.5 microg/kg/min. Dobutamine was added in 23% of the patients (group 1), 32% (group 2) and 95% (group 3). Adrenalin/amrinonum was required in 40% of the patients in group 3, 5% in group 2 and none in group 1. Group 1 patients had a better improvement of cardiac performance than group 2, while other parameters did not differ. Three months follow up of hospital survivors showed no group differences. CONCLUSIONS: The use of preoperative IABP in high risk patients lowers hospital mortality and shortens the stay in ICU, due to improved cardiac performance, compared to a controls. The procedure was cost-beneficial. One day preoperative IABP treatment improves cardiac performance more than 1-2 h preoperative IABP treatment, but does not significantly affect the outcome in terms of hospital mortality or postoperative morbidity.

Reactive thrombocytosis after coronary bypass surgery. An important risk factor.

Reactive thrombocytosis (RT) has earlier been reported to occur as a response to various situations and conditions, such as post-splenectomy, hematopoietic disorders, major trauma and operations, neoplasms and inflammations. In cardiac surgery the main interest has focused on thrombocytopenia that occurs after cardiopulmonary bypass (CPB) and the risk of postoperative bleeding, rather than the possibility of a late occurrence of RT as a risk factor for thrombotic complications after coronary artery bypass grafting (CABG). Between 1989 and 1992, on routine blood examinations we noticed a group of CABG patients (n = 297, Group II, 19.5%) that, 1 week after operation, showed thrombocytosis with significantly increased platelet count (521 +/- 96 x 10(3)/mm3) compared to patients with normal platelet counts (Group I, n = 1521, 185 +/- 125 x 10(3)/mm3); P < 0.001. Patient characteristics, coronary angiography findings, operative data and perioperative complications were analyzed for the two groups. There were significantly more patients with hyperlipidemia, smoking and previous myocardial infarction in Group II than in Group I; P < 0.05. Age, sex, clinical characteristics, angiography findings and operative data did not differ between the groups. There were no differences in postoperative bleeding or the need of transfusion between the groups. However, Group II (RT) patients had significantly more postoperative myocardial infarctions, 4.4% compared to 0.7% Group I; P < 0.001. Early symptomatic vein graft occlusion (0-7 days postoperatively) was not different between the groups, while there were significantly move late symptomatic vein graft occlusions (7-60 days postoperatively) in Group II (RT) 4.4% than in Group I 1.1%; P < 0.001.(ABSTRACT TRUNCATED AT 250 WORDS)

Autologous platelet sequestration in patients undergoing coronary artery bypass grafting.

OBJECTIVES: Blood conservation remains an important issue for patients undergoing cardiac surgery with cardiopulmonary bypass. Platelet sequestration (PSQ) is an aggressive autologous blood conservation method, whose effectiveness is still debated. The main objective of the present study was to evaluate whether PSQ reduces postoperative blood transfusion requirements in patients undergoing coronary artery bypass grafting (CABG) and to determine if PSQ is a cost-effective blood conservation method. MATERIAL AND METHODS: All adult patients admitted for CABG entered the study. Exclusion criteria were: recent blood transfusion (<7 days), a platelet count of 150x10(3)/microl or less, hematocrit less than 35% and body weight 50 kg or less. The sequestration was aim 20% or more of the total platelet plasma volume. The sequestration protocol was three sequestration cycles performed just prior to surgery. The concentrated platelet portion was reinfused after weaning from the cardiopulmonary bypass. Hundred seven parameters/patients were recorded. Sixty patients entered the study; 30 in the PSQ group and 30 controls (CTR). RESULTS: Patient characteristics, operation data, preoperative hematology and coagulation parameters did not differ between the groups. In the PSQ group a mean of 433+/-34 ml concentrated platelet portion was collected. The mean platelet count in the concentrated platelet portion was 749+/-157x10(3)/microl, resulting in a platelet yield of 28+/-6% (2040%). The average total chest tube blood loss was 423 ml (PSQ) compared to 858 ml (CTR), p<0.001. A greater number of CTR patients required blood transfusion postoperatively (23) compared to PSQ (3), P<0.001, and fluid requirements were also significantly increased in the control group, P<0.001. No statistical differences in hematology and coagulation parameters between the groups were observed. The hospital mortality was low and the incidence of postoperative complications was few and without group differences. Post-extubation gas exchange was better in PSQ patients compared to CTR. CONCLUSIONS: A preoperative PSQ of a minimum 20% of the total platelet plasma volume resulted in significantly lower postoperative blood loss and fluid and blood transfusion requirements compared to controls. Post-extubation gas exchange was also better after PSQ. Only one patient did not tolerate the sequestration. No other adverse effects of the procedure were observed.

Resistance and tolerance of the myocardium to ischemia.

Since 1967, the authors have abandoned coronary perfusion in valve, particularly aortic, surgery. Some of the difficulties encountered during defibrillation at the period where coronary perfusion was always used have dramatically decreased. Extra-corporeal-circulation is now performed under moderate hypothermia--28 to 30 degrees C--which gives excellent myocardial protection for aortic cross clamping time of 30 to 60 minutes. In coronary artery surgery, the same technique is now used, after having wrongly believed previously that coronary perfusion was indicated. In conclusion, we feel that coronary perfusion is not indicated any more but in very exceptional cases.