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Background Although often short-lived and self-limiting, postoperative atrial fibrillation (POAF) is a well-recognized postoperative complication of cardiac surgery and is associated with a 2-fold increase in cardiovascular mortality and morbidity. Objective Our aim was to determine whether intraoperative bilateral pulmonary vein radiofrequency ablation decreases the incidence of POAF in patients undergoing coronary artery bypass grafting (CABG). Methods A total of 175 patients undergoing CABG was prospectively randomized to undergo adjuvant bilateral radiofrequency pulmonary vein ablation in addition to CABG (group A; n=89) or CABG alone (group B; n=86). Intraoperative pulmonary vein isolation was confirmed by the inability to pace the heart via the pulmonary veins after ablation. All patients received postoperative β-blocker. Results There was no difference in the incidence of POAF in the treatment group who underwent adjuvant pulmonary vein ablation (group A; 37.1%) compared with the control group who did not (group B; 36.1%) ( P = .887). There were no differences in postoperative inotropic support, antiarrhythmic drug use, need for oral anticoagulation, and complication rates. The mean length of postoperative hospital stay was 8.2 ± 6.5 days in the ablation group and 6.7 ± 4.6 days in the control group ( P Conclusion Adjuvant pulmonary vein isolation does not decrease the incidence of POAF or its clinical impact but increases the mean length of stay in the hospital. The mechanism of POAF does not appear to depend on the pulmonary veins.

Cardiac retransplantation remains the most viable option for patients with allograft heart failure; however, careful patient selection is paramount considering limited allograft resources. We analyzed clinical outcomes following retransplantation in an academic, tertiary care institution.Between 1981 and 2011, 593 heart transplantations, including 22 retransplantations were performed at our institution. We analyzed the preoperative demographic characteristics, cause of allograft loss, short- and long-term surgical outcomes and cause of death among patients who had cardiac retransplantations.Twenty-two patients underwent retransplantation: 10 for graft vascular disease, 7 for acute rejection and 5 for primary graft failure. Mean age at retransplantation was 43 (standard deviation [SD] 15) years; 6 patients were women. Thirteen patients were critically ill preoperatively, requiring inotropes and/or mechanical support. The median interval between primary and retransplantation was 2.2 (range 0-16) years. Thirty-day mortality was 31.8%, and conditional (30 d) 1-, 5- and 10-year survival after retransplantation were 93%, 79% and 59%, respectively. A diagnosis of allograft vasculopathy (p = 0.008) and an interval between primary and retransplantation greater than 1 year (p = 0.016) had a significantly favourable impact on 30-day mortality. The median and mean survival after retransplantation were 3.3 and 5 (SD 6, range 0-18) years, respectively; graft vascular disease and multiorgan failure were the most common causes of death.Long-term outcomes for primary and retransplantation are similar if patients survive the 30-day postoperative period. Retransplantation within 1 year of the primary transplantation resulted in a high perioperative mortality and thus may be a contraindication to retransplantation.

Background To date, the etiologic factors involved in the development of allograft coronary disease remain speculative and the treatment uncertain. The purpose of this study was to review the relationship of clinical, angiographic, and pathologic features of cardiac allograft vascular disease in a large population of heart transplant recipients followed for up to 15 years. Methods From 1981 to 1996, 789 angiograms from 255 cardiac allografts were reviewed to determine the prevalence and severity of coronary artery disease. Demographic, clinical, and laboratory variables were analyzed to identify factors associated with the presence of angiographic coronary artery disease. In addition, pathologic examination was performed on many of the lost grafts. Results Unsuspected severe donor coronary artery disease may be responsible for up to 10% of early graft failures. Angiographic coronary artery disease prevalence increased by approximately 10% with every 2-year interval after transplantation. Angiographic coronary artery disease consisted most often of minor luminal irregularities. Severe disease occurred in 12% of patients. At 1 year, the most significant factors associated with the presence of coronary artery disease were older donor age and the number of rejection episodes. Immunologic factors as well as traditional coronary risk factors such as hypercholesterolemia and hyperglycemia may play an important role in the genesis and progression of later-developing abnormalities. Conclusions Cardiac allograft coronary artery disease is a major limiting factor to the long-term success of cardiac transplantation. Immune processes, as well as traditional coronary artery disease risk factors, appear to play a role in the development of this disease.

Background and Aim: We have shown that cumulative sum (CUSUM) failure analysis may be more sensitive than standard statistical methods in detecting a cluster of adverse patient outcomes after cardiac surgical procedures. We therefore applied CUSUM, as well as standard statistical techniques, to analyze a surgeon's experience with off-pump coronary artery bypass grafting (OPCAB) and on-pump procedures to determine whether the two techniques have similar or different outcomes. Methods: In 320 patients undergoing nonemergent, first time coronary artery bypass grafting, preoperative patient characteristics, rates of mortality and major complications, and ICU and hospital lengths of stay were compared between the on-pump and OPCAB cohorts using Fisher's exact tests and Wilcoxon two sample tests. Predicted mortality and length of stay were determined using previously validated models of the Cardiac Care Network of Ontario. Observed versus expected ratios of both variables were calculated for the two types of procedures. Furthermore, CUSUM curves were constructed for the on-pump and OPCAB cohorts. A multivariable analysis of the predictors of hospital length of stay was also performed to determine whether the type of coronary artery bypass procedure had an independent impact on this variable. Results: The predicted mortality risk and predicted hospital length of stay were almost identical in the 208 on-pump patients ( 2.2 ± 3.9% ; 8.2 ± 2.5 days) and the 112 OPCAB patients ( 2.0 ± 2.2% ; 7.8 ± 2.1 days). The incidence of hospital mortality and postoperative stroke were 2.9% and 2.4% in on-pump patients versus zero in OPCAB patients (p= 0.09 and 0.17, respectively). Mechanical ventilation for greater than 48 hours was significantly less common in OPCAB (1.8%) than in on-pump patients (7.7%, p= 0.04). The rate of 10 major complications was 14.9% in on-pump versus 8.0% in OPCAB patients (p= 0.08). OPCAB patients experienced a hospital length of stay that was a median of 1.0 day shorter than on-pump patients (p= 0.01). The observed versus expected ratio for length of stay was 0.78 in OPCAB patients versus 0.95 in on-pump patients. On CUSUM analysis, the failure curve in OPCAB patients was negative and was flatter than that of on-pump patients throughout the duration of the study. Furthermore, OPCAB was an independent predictor of a reduced hospital length of stay on multivariable analysis. Conclusions: OPCAB was associated with better outcomes than on-pump coronary artery bypass despite a similar predicted risk. This robust finding was documented on sensitive CUSUM analysis, using standard statistical techniques and on a multivariable analysis of the independent predictors of hospital length of stay.(J Card Surg 2002;17:520-528)

Background . New technology has enabled surgeons to attempt totally endoscopic coronary artery bypass grafting. Our purpose was to compare three different techniques of totally endoscopic anastomosis using a porcine animal model. Methods . Porcine hearts were excised and the right coronary artery was dissected free for use as an arterial graft. The hearts were placed in a human thoracic model and an endoscopic arterial anastomosis between the free right coronary artery and the left anterior descending coronary artery was performed using one of the following: (1) two-dimensional visualization with straight endoscopic instruments (n = 8); (2) three-dimensional head-mounted visualization with curved endoscopic instruments (n = 7); or (3) three-dimensional visualization with robotic telemanipulation (n = 8). Pathologic analysis of suture placement, vessel trauma, and patency was performed. Anastomoses were graded according to quality, ease, and patency using a seven-point Likert scale (1 = excellent, 7=very poor). Results . Endoscopic anastomotic ease and quality were significantly improved when three-dimensional visualization and curved endoscopic instruments were employed. Telemanipulation enhanced the process and provided the best operative results with regard to time required to construct the anastomosis, as well as ease and quality. Conclusions . Totally endoscopic anastomosis is feasible using currently available technology. Three-dimensional visualization and robotic telemanipulation significantly facilitate anastomosis construction and will likely benefit clinical operative outcome.

High-risk patients experience substantially more compli cations after coronary artery bypass grafting (CABG). We hypothesized that these patients are uniquely vulner able to cardiopulmonary bypass and compared postop erative outcomes between high-risk patients undergo ing off-pump CAB (OPCAB) and conventional CABG. Prospective provincial cardiac care registry and retro spective chart data were reviewed for 1,850 consecutive patients at our institution between January 1996 and January 1999. From this, 235 patients, 36 OPCAB and 199 CABG, were identified as high risk (modified Parson net score ≥15). Risk factor analysis showed the popula tions were equivalent in perioperative risk with mean modified Parsonnet scores of 18.1 ± 3.4 (OPCAB) and 18.7 ± 4.2 (CABG) (P = .4). In total, 6% of OPCAB and 40% of CABG patients suffered major complications leading to extended hospital/intensive care unit (ICU) stay or death ( P ≤ .001). Mean hospital stays were 7.0 ± 4.0 days (OPCAB) and 10.6 ± 10.2 days (CABG) ( P ≤ .001). Mean ICU stays were 23.9 ± 9.7 hours (OPCAB) and 64.9 ± 128.3 hours (CABG) ( P ≤ .001). Mortality was 0% in the OPCAB group and 6% in the CABG group (P = .2). Multivariate predictors of experiencing a major complication were: use of cardiopulmonary bypass (OR 5.1, 95 Cl 2.1-12.1), age > 80 (OR 2.5, 95 Cl 1.7-7.5), female (OR 3.0, 95 Cl 1.6-5.4), repeat operation (OR 2.5, 95 Cl 1.2-5.4), and ejection fraction

The advances in immunotherapy, along with a liberalization of eligibility criteria have contributed significantly to the ever increasing demand for donor organs. In an attempt to expand the donor pool, transplant programs are now accepting older donors as well as donors from more remote areas. The purpose of this study is to determine the effect of donor age and organ ischemic time on survival following orthotopic heart transplantation (OHT).From April 1981 to December 1996 372 adult patients underwent OHT at the University of Western Ontario. Cox proportional hazards models were used to identify predictors of outcome. Variables affecting survival were then entered into a stepwise logistic regression model to develop probability models for 30-day- and 1-year-mortality.The mean age of the recipient population was 45.6 +/- 12.3 years (range 18-64 years: 54or = 30; 237 were 31-55; 9156 years). The majority (329 patients, 86.1%) were male and the most common indications for OHT were ischemic (n = 180) and idiopathic (n = 171) cardiomyopathy. Total ischemic time (TIT) was 202.4 +/- 84.5 minutes (range 47-457 minutes). In 86 donors TIT was under 2 hours while it was between 2 and 4 hours in 168, and more than 4 hours in 128 donors. Actuarial survival was 80%, 73%, and 55% at 1, 5, and 10 years respectively. By Cox proportional hazards models, recipient status (Status I-II vs III-IV; risk ratio 1.75; p = 0.003) and donor age, examined as either a continuous or categorical variable ([age35 vsor = 35; risk ratio 1.98; p0.001], [age50 vsor = 50; risk ratio 2.20; p0.001], [age35 vs 35-49 versusor = 50; risk ratio 1.83; p0.001]), were the only predictors of operative mortality. In this analysis, total graft ischemic time had no effect on survival. However, using the Kaplan-Meier method followed by Mantel-Cox logrank analysis, ischemic time did have a significant effect on survival if donor age was50 years (p = 0.009). By stepwise logistic regression analysis, a probability model for survival was then developed based on donor age, the interaction between donor age and ischemic time, and patient status.Improvements in myocardial preservation and peri-operative management may allow for the safe utilization of donor organs with prolonged ischemic times. Older donors are associated with decreased peri-operative and long-term survival following. OHT, particularly if graft ischemic time exceeds 240 minutes and if these donor hearts are transplanted into urgent (Status III-IV) recipients.

Background . Myocardial revascularization without cardiopulmonary bypass has been proposed as a potential therapeutic alternative in high-risk patients undergoing coronary artery bypass grafting. To evaluate this possibility we compared 15 high-risk (HR) patients in whom minimally invasive direct coronary artery bypass grafting was used as the method of revascularization with 41 consecutive patients who underwent conventional coronary artery bypass grafting during 1 month. Methods . Patients undergoing myocardial revascularization without cardiopulmonary bypass were significantly older than their low-risk (LR) counterparts (72.2 ± 11.6 versus 63.3 ± 9.7 years, p = 0.006). The demographic profile for HR versus LR patients was as follows: female patients, 60.0% versus 26.8%, p = 0.02; diabetes, 20.0% versus 24.4%, p = 0.7; prior stroke, 33.3% versus 7.4%, p = 0.03; chronic obstructive pulmonary disease, 60.0% versus 9.8%, p p = 0.03, congestive heart failure, 26.6% versus 9.8%, p = 0.09; impaired left ventricular (ejection fraction p = 0.07; urgent operation, 86.6% versus 46.3%, p p = 0.003. Results . There were no deaths in the HR group and one death in the LR group. The average intensive care unit stay was 1.1 ± 0.5 days in HR patients versus 1.6 ± 1.6 days in LR individuals ( p = 0.2), and the average hospital stay was 6.1 ± 1.8 versus 7.3 ± 4.4 days, respectively ( p = 0.3). We used an acuity risk score index developed by the Adult Cardiac Care Network of Ontario to predict outcome in the HR group. The expected intensive care unit stay in HR patients was 4.1 ± 1.2 days (versus the observed stay of 1.1 ± 0.5 days, p p p = 0.3. A cost regression model was used to examine predicted versus actual cost (in Canadian dollars) for the HR patient cohort (based on Ontario Ministry of Health funding). The expected cost for the HR cohort would have been $11,997 per patient. In contrast, the average cost for these 15 patients was $5,997 per patient, an estimated cost saving of 50%. Conclusions . Myocardial revascularization without cardiopulmonary bypass appears to be a safe and cost-effective therapeutic modality for HR patients requiring myocardial revascularization.

An international series of pulmonary retransplantation was updated to identify the predictors of survival in the intermediate-term after reoperation for obliterative bronchiolitis. The study cohort included 32 patients with end-stage obliterative bronchiolitis who underwent retransplantation in 15 North American and European centers between 1988 and 1992. Five types of retransplantation procedures were done, including repeat ipsilateral single lung transplantation (7 patients), repeat contralateral single lung transplantation (8 patients), repeat double lung transplantation (3 patients), double lung transplantation after a previous single lung transplantation (3 patients), and single lung transplantation after a previous double lung or heart-lung transplantation (11 patients). The mean interval between transplants was 564 ± 51 days (range 187 to 1589 days). Postoperative follow-up was 100% complete and the average follow-up in surviving patients was 678 ± 63 days. Actuarial survival was 72%, 53%, 50%, 41%, and 33% at 1, 3, 6, 12, and 24 months, respectively. Survival did not differ according to the age, preoperative diagnosis, ambulatory or ventilator status, or cytomegalovirus serologic status of the recipient before reoperation. Life-table and Cox proportional hazards analysis identified the type of retransplantation procedure and the year of reoperation as significant ( p HORAC C ARDIOVASC S URG 1994;107:755-63)

Background: Patients with heart disease are frequently maintained on a regimen of aspirin because of its ability to decrease thrombotic complications and reduce the prevalence of unstable angina and myocardial infarction. Aspirin-induced platelet acetylation also increases bleeding caused by impairment of platelet function during cardiac surgery. Methods: Between October 1990 and November 1991 this double-blind, randomized, placebo-controlled, parallel group interventional study examined the efficacy of high-dose aprotinin administration (up to 7 million KIU) to decrease blood loss and transfusion requirements in patients receiving aspirin within 48 hours of undergoing coronary bypass or valvular heart operations. Primary outcome measures in this study were total volume of blood loss (intraoperative blood loss plus postoperative chest tube drainage) and volume of transfusion during hospitalization. Results: Patients treated with aprotinin ( n = 29) had significantly lower total blood loss (1409 ± 232 ml versus 2765 ± 248 ml; p = 0.0002), intraoperative blood loss (503 ± 53 ml versus 1055 ± 199 ml; p = 0.0001), postoperative blood loss (906 ± 204 ml versus 1710 ± 202 ml; p = 0.0074), and prevalence of transfusion (59 % versus 88 % of patients; p = 0.016) than the placebo group ( n = 25). The prevalence of complications including myocardial infarction was similar in the two groups. Conclusions: High-dose aprotinin significantly reduces blood loss and red blood cell transfusions in patients receiving aspirin who undergo cardiac operations.

Having previously demonstrated in a prospective study of 200 coronary artery bypass (CAB) patients that by using the brain as an index organ, interventions to improve cerebral oxygenation would have systemic outcome benefits, we undertook a post hoc analysis of the diabetic subset (n = 57) of the overall study group to determine whether the outcomes of these patients were similarly improved.Case-report forms for the 200 CAB patients study patients with a preoperative diagnosis of diabetes mellitus were stratified to intraoperative cerebral regional oxygen saturation (rSO2) monitoring with active display and a treatment intervention protocol (intervention group, n = 28) or to blinded rSO2 monitoring (control group, n = 29) and analyzed.There were no significant differences between the 2 groups in overall risk factors, although there were trends toward a higher body mass index, a worse angina score, a worse grade of ventricle, and greater use of off-pump coronary revascularization in the control group of patients. The 2 groups were similar with respect to overall insulin dosage and perioperative blood glucose concentrations. Significantly more diabetic patients in the control group demonstrated profound cerebral desaturation, with an area under the curve of50%/min (P = .043; d = 0.55), longer intensive care unit (ICU) stays (P = .045; d = 0.58), and longer overall postoperative hospital stays (P = .036; d = 0.47), compared with patients in the intervention group. Compared with the intervention group, the control group had a significantly higher incidence of sternal wound infection (P = .028; φ = 0.31) and a significantly greater number of diabetic patients with2 postoperative complications (P = .006; φ = 0.37). An analysis after removing the patients who underwent off-pump surgery revealed that the control group had significantly more patients with sternal wound infections (5 versus 0; P = .047) and ≥2 postoperative complications (6 versus 0; P = .008) than the intervention group, as well as a trend toward longer ICU and postoperative hospitalization stays in the control group.Monitoring and management of cerebral rSO2 in diabetic CAB patients avoid profound cerebral desaturation and are associated with significantly lower incidences of complications and shorter postoperative lengths of stay.A post hoc analysis of the diabetic cohort of a prospective, randomized, and blinded study of CAB patients revealed that those in whom cerebral oxygen saturation was actively monitored and maintained demonstrated significantly lower incidences of complications, resulting in shorter ICU and postoperative hospital stays compared with an unmonitored control group.

The mechanisms of improved functional capacity over the first year after cardiac transplantation are not well studied. To assess the contribution of cardiac changes to this improvement, the serial evolution of upright rest and exercise hemodynamics during graded upright bicycle exercise was studied in 17 patients at 3 and 12 months after heart transplantation. Heart rate responsiveness, reflected by rapid heart rate acceleration on sitting and rapid deceleration after exercise, developed in the first year. Pulmonary capillary wedge pressure was lower at 1 year, both at rest and at peak exercise (10 +/- 3 vs 13 +/- 5 mm Hg at rest supine and 14 +/- 6 vs 18 +/- 8 mm Hg at peak exercise, p less than 0.05). Similarly, right atrial pressures were also significantly lower at 1 year (4 +/- 2 vs 6 +/- 3 mm Hg at rest supine and 6 +/- 5 vs 11 +/- 5 mm Hg at peak exercise, p less than 0.05). Cardiac index at peak exercise was greater at 12 months (6.4 +/- 1.3 vs 5.8 +/- 0.8 liters/min/m2, p less than 0.05), mediated primarily by higher exercise heart rate (135 +/- 16 vs 125 +/- 12 beats/min, p less than 0.05). In the first year after heart transplantation, improved rest and exercise hemodynamics and heart rate responsiveness contribute significantly to the improved functional capacity observed in these patients.

and three interactive table-mounted instrument manipulators. Details of this system have been previously described.1 Starting September 18, 1999, 18 patients with single-vessel coronary disease involving the left anterior descending coronary artery underwent beating-heart minimally invasive coronary artery bypass grafting with telerobotic assistance after approval by the university’s institutional ethics committee. Totally robotic, closed-chest procedures were completed in 6 male patients and are the subject of this report. After establishment of general anesthesia with a doublelumen endotracheal tube, each patient was placed in a 45° right lateral decubitus position. The left arm was abducted to permit the insertion of three 5-mm access ports, while avoiding external robotic arm collisions. The left internal thoracic artery (LITA) was identified and dissected as a pedicle from the first to sixth ribs with voice-activated robotic and video assistance using the Harmonic Scalpel (Ethicon EndoSurgery, Inc, Somerville, NJ). During the procedure, warm carbon dioxide gas was insufflated into the pleural cavity up to a pressure of 5 to 10 mm Hg. The left anterior descending coronary artery (LAD) was stabilized with a prototype articulating endoscopic stabilizer (Fig 1). A specially designed sternal elevator was used in 3 of the patients to increase anteroposterior intrathoracic working space. A 5-mm 0° endoscope and assistant instruments were passed through working ports. The patients were then systemically heparinized and the LAD prepared for anastomosis. The LITA Significant advances have been made in computer-assisted robotic coronary surgery in the past 2 years. Although limited success has been achieved with totally endoscopic, robotassisted bypass on the arrested heart, the ultimate objective is to perform a beating-heart procedure. To date, technical limitations have prevented this goal from being accomplished. We describe our initial clinical experience using robotic instrumentation and voice-controlled camera guidance (Zeus; Computer Motion Inc, Goleta, Calif) in performing closedchest, beating-heart coronary artery bypasses. Patients and methods. The Zeus endoscopic instrument control system is a supervised online robotic system consisting of three components: a surgeon’s console, a computer controller, CLOSED-CHEST CORONARY ARTERY BYPASS GRAFTING ON THE BEATING HEART WITH THE USE OF A COMPUTER-ENHANCED SURGICAL ROBOTIC SYSTEM

From 1965 to 1974 extensive research was carried out concerning the effects of experimental lung reimplantation and allografting on the surface tension properties of pulmonary surfactant. Since then, surfactant has been more rigorously examined in terms of its composition and function, and the potential roles of three surfactant-associated proteins have been established. Furthermore, surfactant replacement therapy for neonatal respiratory distress syndrome has come of age. The efficacy of surfactant treatment for adult respiratory distress syndrome is currently under clinical scrutiny, and experimental work on alterations in surfactant after lung transplantation has resumed after a 15-year hiatus. This article reviews current knowledge of the pulmonary surfactant system, as well as previous studies of the changes in surfactant after experimental lung transplantation. The experience in surfactant replacement therapy for the neonatal and adult respiratory distress syndromes is briefly described. Suggestions are made concerning the potential experimental and clinical applications of surfactant analysis and replacement therapy in lung transplantation.

Although anatomic reinnervation of the donor heart is unlikely after transplantation, individual subjects have been noted to show near physiologic heart rate (HR) responses to exercise. To assess development of this phenomenon, we studied HR changes in response to orthostasis and treadmill exercise in 52 orthotopic cardiac transplant recipients grouped according to time after transplantation. In group 1 (2.0 +/- 0.9 months), no significant increase in HR was seen up to 100 cardiac cycles after standing. A maximal acceleration of 4.0 +/- 3.8 beats was seen within 100 cardiac cycles after standing in group 2 (15.8 +/- 5.6 months). Patients in group 3 (42.4 +/- 12.4 months) showed significant cardioacceleration by 5 cardiac cycles after standing to a maximum of 10.7 +/- 5.8 beats/min within the first 100 cardiac cycles. During exercise, HR increased more rapidly during the first minute in group 3 compared with group 1 (p less than 0.01). After exercise, HR continued to increase in group 1 but decreased rapidly in the other groups, most notably group 3 (-26.5 +/- 16.5 by 2 minutes, p less than 0.0001 vs groups 1 and 2). These data indicate development of functional reinnervation after orthotopic heart transplantation. The phenomenon of early acceleration of the HR after orthostasis and rapid deceleration after exercise in transplant recipients implies a local cardiac mechanism rather than response to circulating catecholamines.

The role of prostaglandin E1 (PgE1) and prostacyclin in enhancing the ischemic tolerance of single-lung grafts was investigated. Fifteen donor dogs underwent pulmonary artery flushing with 60 mL/kg of 4 °C modified Euro-Collins solution; 5 dogs each received a 15-minute infusion of PgE1, prostacyclin, or saline solution before flushing. After 12 hours of storage at 4 °C, left lung transplantation was performed in 15 recipient dogs. Measurements were performed after 10 minutes of right pulmonary artery snaring before transplantation, after transplantation, and after 2, 4, and 6 hours of reperfusion. At 6 hours, the oxygen tensions (on 100% O2) were 478 ± 64, 296 ± 75, 79 ± 12, and 71 ± 23 mm Hg in control (nontransplanted), prostacyclin-, PgE1-, and saline-treated dogs, respectively (p < 0.05, prostacyclin or control versus saline and PgE1 dogs). Mean pulmonary artery pressures increased within each group during reperfusion, but were not significantly different among groups. Similarly, peak inspiratory pressures and wet weight to dry weight ratios were not significantly different among groups after 6 hours of reperfusion. We conclude that donor pretreatment with prostacyclin is associated with superior oxygen transfer in canine lung allografts after 12 hours of cold storage, transplantation, and 6 hours of reperfusion. In this model, donor pretreatment with PgE1 conferred no benefit to prolonged lung allograft preservation.

The results of heart-lung transplantation are improving with increasing experience in postoperative management, but obliterative bronchiolitis may still develop late postoperatively. We have performed 19 heart-lung transplants, with 1-month, 1-year, and 2-year actuarial survival rates of 95% ± 5%, 84% ±8%, and 69% ± 16%, respectively. Three early recipients died of bronchiolitis, and four patients who were operated on more than 2 years ago are currently being followed up with bronchiolitis. Since August 1988, 13 surviving recipients have undergone serial postoperative bronchoscopies and transbronchial biopsies with topical analgesia. Diffuse bronchomalacia, involving the main bronchi down to the fifth-order bronchi bilaterally, has developed in four patients with bronchiolitis 9 + 2 months after the diagnosis of bronchiolitis was confirmed. Pulmonary function tests have revealed a lower ratio of forced expiratory volume in 1 second to forced vital capacity, lower specific airway conductance, and higher airway resistance in heart-lung recipients with bronchomalacia than in patients with bronchiolitis alone. We conclude that diffuse bronchomalacia occurs frequently in heart-lung transplant recipients who have obliterative bronchiolitis. Bronchomalacia worsens the functional airflow obstruction caused by bronchiolitis and may play an important role clinically in the declining respiratory status of heart-lung transplant recipients.

Background There is a relative dearth of information on how the resident's level of training affects patient outcomes in cardiac surgery. We designed this study to determine if there were any significant differences in patient demographics and clinical outcomes of coronary artery bypass procedures (CABG) performed by residents of PGY 4/lower, residents of PGY 5/6, fellows, or consultants. Methods Standardized preoperative, intraoperative, and postoperative variables were prospectively collected and analyzed on 2906 isolated CABG procedures, performed between July 1999 and March 2006 with the primary surgeon prospectively classified as PGY4/lower, PGY5/6, fellow, and consultant. Results The number of cases performed by residents of PGY4/lower, PGY5/6, fellows and consultants were 179, 263, 301, and 2163, respectively. Preoperative demographics and comorbidities were similar except PGY4/lower group had more diabetics and consultant group had more patients requiring IABP. More non-LIMA arterial conduits were used in the consultant and fellow groups. However, there were neither significant differences in the mean number of grafts nor in the composite postoperative morbidity, median ICU, and hospital lengths of stay. Observed in-hospital mortality was 2.2%, 1.5%, 1.7%, and 2.7% (p = 0.49), respectively. Conclusions Preoperative patient demographics and operative data were similar in all groups except that patients requiring IABP preoperatively were more likely operated on by consultants and arterial revascularization was performed more commonly by consultants and fellows. Postoperative mortality and morbidity rates were similar among all groups, thus demonstrating that with appropriate supervision, trainees of all levels can safely be taught CABG.

Several studies have reported the incidence, morbidity, and mortality of general surgical conditions (GSCs) in orthotopic heart transplant (OHT) patients. The following is the largest reported series of such patients and the first study with sufficient patient numbers to formally evaluate peritransplant variables as risk factors for GSC development.A GSC was defined as a condition for which a general surgeon had been consulted or as a general surgical condition recognized at the time of autopsy. The records of 453 consecutive patients who underwent OHT between 1981 and 1999 were reviewed to identify patients who developed a GSC. Kaplan-Meier actuarial analysis on this cohort, and univariate and multivariate logistic regression models applied to a subpopulation of 324 consecutive OHT patients between 1987 and 1997 were used to determine factors associated with and predictive of GSC after OHT.Of 453 OHT patients, 371 (81.9%) were men, and the average age was 44.5 +/- 15 (standard deviation) years. Median followup was 2,086 days (range 1 to 6,642 days). Ninety-three patients (20.5%) developed 111 GSCs. Of these, 78 were men, and the average age was 49.9+/-10.2 years. There were 83 general surgical interventions. Actuarial analyses revealed that age greater than 50 years, pretransplant diagnosis of ischemic (PTDxI) versus nonischemic heart disease, and previous general surgical history were factors associated (p0.05) with a higher GSC incidence. Gender, more urgent transplant priority status, cardiopulmonary bypass time, total graft ischemic time, and intensive care unit length of stay were not associated with GSC. Factors associated with GSC on univariate analysis, with odds ratios (ORs) and 95% confidence intervals (CIs) included: age analyzed as a continuous variable (OR 1.04 per year; CI 1.01, 1.06 per year; p = 0.0021), PTDxI (OR 2.40; CI 1.39, 4.15; p = 0.0016), and pretransplant general surgical history (OR 3.35; CI 1.65, 6.82; p = 0.0008). Multivariate analysis revealed that only pretransplant general surgical history (OR 3.27; CI 1.58, 6.76; p = 0.0004) and PTDxI (OR 2.37; CI 1.35, 4.16; p = 0.0023) were associated with subsequent development of GSC.A pretransplant diagnosis of ischemic heart disease and previous history of a general surgical procedure are two independent risk factors that predispose OHT patients to development of GSC. Because GSC may arise insidiously in immunosuppressed patients, identification of OHT patients at higher risk for GSC will permit timely intervention decisions, decreasing morbidity and mortality in this challenging group of patients.

Bypass surgery in the elderly (age70 years) has increased mortality and morbidity, which may be a consequence of cardiopulmonary bypass. We compare the outcomes of a cohort of elderly off-pump coronary artery bypass (OPCAB) patients with elderly conventional coronary artery bypass grafting (CABG) patients.Chart and provincial cardiac care registry data were reviewed for 30 consecutive elderly OPCAB patients (age 74.7 +/- 4.2 years) and 60 consecutive CABG patients (age 74.9 +/- 4.1 years, p = 0.82) with similar risk factor profiles: Parsonnet score 17.2 +/- 8.1 (OPCAB) versus 15.6 +/- 6.5 (CABG), p = 0.31; and Ontario provincial acuity index 4.5 +/- 1.9 (OPCAB) versus 4.3 +/- 2.0 (CABG), p = 0.65.Mean hospital stay was 6.3 +/- 1.8 days for OPCAB patients and 7.7 +/- 3.9 days for CABG patients (p0.05). Average intensive care unit stay was 24.0 +/- 10.9 h for OPCAB patients versus 36.6 +/- 33.5 h for CABG patients (p0.05). Atrial fibrillation occurred in 10.0% of OPCAB patients and 28.3% of CABG patients (p0.05). Low output syndrome was observed in 10% of OPCAB patients and 31.7% of CABG patients (p0.05). Cost was reduced by $1,082 (Canadian) per patient in the OPCAB group. Postoperative OPCAB graft analysis showed 100% patency.OPCAB is safe in the geriatric population and significantly reduces postoperative morbidity and cost.

It is commonly believed that pulsatile flow generated by the pumping action of the heart is dampened out by the time it reaches the microcirculation. In clinical practice, most of the cardiopulmonary bypass pumps and ventricular assist devices are nonpulsatile. To test the hypothesis that pulsatile flow generated by the heart does exist at the microvascular level, intravital microscopy of a large animal model (goat) was developed to visualize and to videorecord the surface microcirculation of the flexor carpi ulnaris muscle from the right forelimb. Density of perfused capillaries and red blood cell velocity in capillaries were measured in five goats during pulsatile perfusion provided by the heart and during a subsequent 3-hr period of nonpulsatile perfusion provided by a centrifugal ventricular assist device (Centrimed, Sarns 3M) that bypassed the heart. Throughout the experiment, the heart rate, innominate artery mean blood pressure, and flow remained unchanged. During the pulsatile regimen, velocities showed regular fluctuations that coincided with the period of the cardiac cycle (range of periods: 0.5-0.8 sec). The peak velocity amplitudes (range: 0.25-0.55 mm/sec) correlated directly with the amplitude of the pulse pressure. During the nonpulsatile regimen, no such correlations were seen. During pulsatile flow and during the 3-hr nonpulsatile period, capillary density remained stable at 24 capillaries/mm of test line but there were significant increases in red cell velocity, from 0.8 to 1.2 mm/sec (P0.05), and in coefficient of variation of velocity (used as an index of flow heterogeneity), from 19 to 34% (P0.05). We conclude that (1) pulsatility exists in the capillary bed and that it directly correlates with the pumping action of the heart and (2) nonpulsatile flow produced by the ventricular assist device does not cause an acute deterioration in microvascular perfusion. We interpret the increase in heterogeneity of flow as an early sign of microvascular dysfunction. Prolonged use of the nonpulsatile device may, therefore, lead to deterioration in perfusion that could compromize the function of the organ.

A 59-year-old man had symptoms of aortic dissection. Computed tomography and angiography showed a large intramural hematoma of the ascending and descending aorta without intimal defect or false lumen. The hematoma resolved completely within 7 weeks with medical treatment. His symptoms recurred 6 months later. Computed tomography and angiography demonstrated a type B dissection with a false lumen and an intimal defect. This case illustrated the progressive nature of aortic dissection without intimai rupture. The diagnostic criteria and therapeutic options are discussed.

Preoperative steroid use has been considered a contraindication to heart-lung as well as lung transplantation. Moreover, most centers delay prednisone administration until 2 to 3 weeks postoperatively until airway healing is secure. We have performed 19 heart-lung transplantations and four single-lung transplantations since 1983. Five recipients (4 heart-lung, 1 single lung) had received prednisone, 5 to 40 mg daily, for 2 to 10 years preoperatively. All recipients were administered prednisone, 0.5 mg/kg daily, starting on postoperative day 1, with a taper to 0.2 mg/kg daily by 4 weeks. Minnesota antilymphocyte globulin (for 10 days), cyclosporine, and azathioprine were also employed. Bronchoscopy, lavage, and transbronchial biopsies were performed every 2 weeks for 3 months postoperatively. No patient had a serious airway complication; 2 heart-lung recipients, not on prednisone preoperatively, had a minor tracheal slough detected on bronchoscopy that resolved spontaneously. Actuarial survival after heart-lung transplantation is 84% +/- 8% and 69% +/- 16% at 1 year and 2 years, respectively. We conclude that prednisone commencing at a dose of 0.5 mg/kg daily from the first postoperative day is a safe practice after heart-lung transplantation. The long-term use of low-dose prednisone before heart-lung transplantation does not preclude normal tracheal healing. The safety of prednisone before and immediately after single-lung transplantation awaits confirmation by further experience.

An intractable contralateral air leak developed in a 46-year-old woman after right single-lung transplantation for emphysema. A left pneumonectomy was performed on postoperative day 17, leaving the patient with only one transplanted lung. Fifteen months postoperatively the patient is well and has satisfactory pulmonary function. Survival with a good quality of life is possible after single-lung transplantation and bilateral sequential pneumonectomies.

To assess the diagnostic applicability of magnetic resonance imaging (MRI) for diagnosis of cardiac allograft rejection, 25 patients who recently underwent cardiac transplantation were studied on a 0.15-tesla resistive system within 24 hours of endomyocardial biopsy. Ten normal volunteers and 4 patients who had recent (within 2 weeks) nontransplant cardiac surgery were also studied. In the 19 transplant patients imaged within 24 days of graft implantation, only 1 had evidence of graft rejection on biopsy. However, all nonrejecting grafts had increased T1 and T2 values, 501 +/- 22 and 61 +/- 6 ms, respectively (mean +/- standard deviation) and the only rejecting graft had values of 496 and 60 ms, respectively. In the normal volunteers mean T1 was 352 +/- 18 ms and T2 was 35 +/- 6 ms. There was no significant difference in T1 and T2 values between patients who underwent nontransplant surgery and control subjects. In patients with nonrejecting transplants who were imaged more than 25 days after surgery, the T1 and T2 values had normalized to 359 +/- 17 ms and 36 +/- 7 ms, respectively (n = 28 images in 20 patients). However, in those grafts with rejection, T1 and T2 were both elevated to 502 +/- 21 ms and 62 +/- 6 ms, respectively (n = 15 in 13 patients); wall thickness was also increased. Fourteen of 15 late rejection events (more than 25 days after surgery) were correctly identified on the basis of increases in T1 and T2 to more than 2 standard deviations above normal.(ABSTRACT TRUNCATED AT 250 WORDS)

The reported high incidence of coronary atherosclerosis in many transplant series led us to critically review our experience in 83 patients who have had selective coronary angiography at ≥1 years after transplantation. Angiograms were reviewed for evidence of coronary vascular disease, and quantitative analysis of multiple coronary artery segments was performed in serial films. Qualitative analysis revealed only 3 of 83 patients with any angiographic abnormality at follow-up, 1 with minimal luminal irregularities in the right coronary artery at 1 year, a second with a 50% diameter stenosis of the proximal left anterior descending artery and minimal irregularity of the proximal circumflex artery at 1 year and a third patient who developed a new 30% diameter eccentric proximal right coronary artery stenosis at 3-year follow-up. The cumulative incidence of graft vascular disease assessed angiographically was therefore 2% at 1 year and 4% at 3 years. Quantitative analysis, however, showed a significant decrease in coronary artery luminal diameter over time. The mean left main coronary artery diameter decreased from 5.4 ± 0.9 mm at 1 year to 4.7 ± 0.8 mm at 3 years (p = 0.0007). A significant reduction in luminal diameter also was found in the following segments (measurements are given 1 vs 3 years): proximal left anterior descending artery (4.4 ± 0.7 vs 4.0 ± 0.5 mm, p = 0.003), mid-left anterior descending (2.7 ± 0.5 vs 2.5 ± 0.4 mm, p = 0.009), proximal circumflex (3.9 ± 0.6 vs 3.6 ± 0.7 mm, p = 0.0003), mid-circumflex (3.0 ± 0.6 vs 2.8 ± 0.7 mm, p = 0.005) and proximal right coronary artery (4.0 ± 0.7 vs 3.7 ± 0.6 mm, p = 0.05). In addition, 7 of 8 hearts obtained at autopsy or retransplant showed significant degrees of diffuse fibrointimal hyperplasia, unsuspected from angiography performed as recently as 7 days earlier. Thus, although segmental coronary vascular disease was uncommon in these patients, diffuse vascular disease may be insidious, progressive and undetectable by current angiographic techniques.

Granular cell myoblastoma is a common lesion of uncertain histogenesis. It commonly affects the tongue, breast, and subcutaneous tissues. However, its occurrence in the tracheobronchial tree is rare. Although generally a benign lesion, isolated malignant granular cell myoblastoma as well as its coexistence with other primary bronchogenic carcinomas has been documented. In spite of recent anecdotal reports advocating endoscopic removal of this lesion, we believe definitive surgical excision is a more rational choice of treatment.

The mechanisms by which the denervated heart responds to supine exercise were assessed by equilibrium gated radionuclide angiography in 18 cardiac transplant recipients 1 to 25 months (mean 11) after surgery. Results were compared with those in 15 normal subjects. Exercise duration among transplant recipients did not differ significantly from that in normal subjects. The heart rate at rest in transplant patients was 30% higher than in normal volunteers. Heart rate increased only 3% between rest and the first stage of exercise in transplant recipients compared with a 37% increase in the normal group (p < 0.001). Cardiac output at rest was similar in both groups although the rate of rise of cardiac output and peak cardiac output were significantly lower among the transplant recipients.In early exercise, the means by which cardiac output increased in the transplant patients differed significantly from normal. In the transplant recipients, the left ventricular end-diastolic volume index increased 14% compared with a decrease of 2% in normal subjects (p < 0.001) during the first stage of exercise. At the same time, the end-systolic volume index increased 6% in the transplant group but decreased 11% in normal subjects (p < 0.001). These changes resulted in an overall increase in stroke volume by 20% in the transplant group compared with only a slight increase (+ 3%) in normal subjects (p < 0.001) during the first stage of exercise. Among transplant recipients, the stroke volume index plateaued after the first stage of exercise, which, in combination with the blunted chronotropic response, resulted in a peak cardiac index 25% lower than that in normal subjects (p < 0.01).These results support the concept that in the transplanted heart, increases in cardiac output at the start of supine exercise occur by augmented stroke volume mediated primarily by an increase in end-diastolic volume, and in normal individuals by an increase in heart rate. Among transplant recipients, peak exercise cardiac index may be lower because of the blunted chronotropic response.

To characterize the spectrum of hemodynamic findings after orthotopic cardiac transplantation, 20 healthy heart transplant recipients with no evidence of cardiac dysfunction by noninvasive testing were studied for 1 to 51 months (mean 15) following surgery. After routine endomyocardial biopsy, right-sided heart pressures and thermodilution cardiac outputs were measured at rest (supine) and during symptom-limited, graded supine exercise. In addition, the effect of respiration on right atrial pressures and waveforms was determined at rest (supine, legs down), and after passive leg raising (volume loading). During exercise, striking increases of pulmonary artery, pulmonary artery wedge and right atrial pressures were seen. The mean pulmonary artery pressure rose 45% during the first stage of exercise (p less than 0.001) and by peak exercise it had increased 87% above resting values. The pulmonary artery wedge pressure increased significantly with passive leg elevation (p less than 0.001) and during the first stage of exercise rose 61% above baseline values. By peak exercise the mean pulmonary artery wedge pressure was more than double the resting value. Similarly, the right atrial mean pressure increased significantly (p less than 0.001) with passive leg elevation and nearly tripled at peak exercise. All values promptly returned to near baseline after exercise. The cardiac output increased 98% during exercise. During early exercise, the rise in cardiac output was mediated primarily by an increase in stroke volume. At rest, there was an abnormal response in right atrial mean pressure during slow deep inspiration in 7 individuals with legs down and in 12 after passive leg elevation (volume loading), including 4 of 10 patients studied beyond 1 year.(ABSTRACT TRUNCATED AT 250 WORDS)