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Background: Increasing numbers of the very elderly are undergoing coronary artery bypass graft surgery (CABG). Short-term results have been studied, but few data are available concerning long-term outcomes., Methods: We conducted a cohort study of 54,397 consecutive patients undergoing primary, isolated CABG surgery between July 1, 1987, and June 30, 2006. Patient records were linked to the Social Security Administration's Death Master File., Results: During 390,871 person-years of follow-up, there were 17,352 deaths. There were 51,149 patients younger than 80 years, 2,661 patients aged 80 to 84 years, and 587 patients aged 85 or more years who underwent isolated CABG surgery. Crude in-hospital survival was 97.2% for those less than 80 years, 98.3% for those aged 80 to 84 years, and 87.6% for those aged 85 or more years. Patients aged 80 or more years were more likely to be female (46.9%), more likely to be emergency priority (10.2%), and more likely to have associated comorbidities than younger patients. Patients aged 85 or more years were more likely to have intraoperative and postoperative morbid events. Among patients younger than 80, median survival was 14.4 years with an annual incidence of death of 4.2%. Among patients 80 to 84 years old, median survival time was 7.4 years, with an annual incidence rate of death of 10.3%. Among patients aged 85 or more years, median survival was 5.8 years, and the annual incidence of death was 13.7%., Conclusions: Although very elderly CABG patients have more comorbidities and more acute presentation than younger patients and their in-hospital mortality rate is high, their long-term survival is surprisingly good.

Background: Predicting risk for aortic and mitral valve surgery is important both for informed consent of patients and objective review of surgical outcomes. Development of reliable prediction rules requires large data sets with appropriate risk factors that are available before surgery., Methods: Data from eight Northern New England Medical Centers in the period January 1991 through December 2001 were analyzed on 8943 heart valve surgery patients aged 30 years and older. There were 5793 cases of aortic valve replacement and 3150 cases of mitral valve surgery (repair or replacement). Logistic regression was used to examine the relationship between risk factors and in-hospital mortality., Results: In the multivariable analysis, 11 variables in the aortic model (older age, lower body surface area, prior cardiac operation, elevated creatinine, prior stroke, New York Heart Association [NYHA] class IV, congestive heart failure [CHF], atrial fibrillation, acuity, year of surgery, and concomitant coronary artery bypass grafting) and 10 variables in the mitral model (female sex, older age, diabetes, coronary artery disease, prior cerebrovascular accident, elevated creatinine, NYHA class IV, CHF, acuity, and valve replacement) remained independent predictors of the outcome. The mathematical models were highly significant predictors of the outcome, in-hospital mortality, and the results are in general agreement with those of others. The area under the receiver operating characteristic curve for the aortic model was 0.75 (95% confidence interval [CI], 0.72 to 0.77), and for the mitral model, 0.79 (95% CI, 0.76 to 0.81). The goodness-of-fit statistic for the aortic model was chi(2) [8 df] = 11.88, p = 0.157, and for the mitral model it was chi(2) [8 df] = 5.45, p = 0.708., Conclusions: We present results and methods for use in day-to-day practice to calculate patient-specific in-hospital mortality after aortic and mitral valve surgery, by the logistic equation for each model or a simple scoring system with a look-up table for mortality rate.

Background: Single-center studies suggest substantial variation in intraaortic balloon pump (IABP) utilization. Our purpose is to examine IABP utilization over time and across medical centers., Methods: This was a prospective cohort of 29,961 consecutive patients undergoing isolated coronary artery bypass graft surgery, between 1995 and 2000, at 10 centers (eight in northern New England and two in Canada)., Results: A total of 2,678 (8.9%) patients received an IABP. The rate of preoperative IABP insertion was 6.3%, and that of intra- or postoperative insertion was 2.6%. During the 6 years, IABP use increased from 7.0% to 10.3% (p(trend) <0.001). Preoperative IABP insertion increased from 5.4% to 7.8% (p(trend) < 0.001). There was no significant increase in intra-/postoperative IABP insertion 1.7% to 3.4% (p(trend) = 0.34). Adjustment for changes in patient and disease characteristics did not substantially alter these results. The rate of IABP use varied substantially by center, from 5.9% to 16.4% (p < 0.001). Adjustment for patient and disease characteristics resulted in variation from 4.8% to 12.8% across the 10 centers (p < 0.001). The adjusted rates of preoperative IABP insertion varied from 3.6% to 13.7% (p < 0.001), and the rates of intra-/postoperative IABP insertion ranged from 1.0% to 5.2% (p < 0.001). There was no significant correlation between the rates of preoperative and intra-/postoperative IABP use (r(s) = 0.085, p = 0.815)., Conclusions: During the 6 years, there was a 47% increase in the rate of IABP utilization. Even after adjustment, there was almost threefold variation in IABP use across centers. This variation likely reflects lack of consensus on the appropriate use of the IABP in CABG patients.

Fifty consecutive patients undergoing coronary artery bypass grafting surgery were studied to evaluate the effect of intermittent anterograde cold cardioplegia (IACCH) and intermittent combined anterograde-retrograde cold cardioplegia (IRCCN) on left ventricular function using transesophageal echocardiography. Global function did not significantly change in both groups, but significantly more inotropes were required in IACCH. Newly developed abnormalities of regional wall motion after cardiopulmonary bypass, which were indicative of ischemic myocardium, were detected in the segments supplied by the right coronary artery in both groups (IACCH, 20%; IRCCN, 16%), by the left circumflex coronary artery only in IACCH (12%) and by the left anterior descending coronary artery only in IRCCN (12%). It is concluded that although global evaluation of left ventricular function did not show any significant change after IACCH and IRCCN under routine management, analysis of abnormalities of regional wall motion provided specific information. In both groups, complete protection of the myocardium was not achieved, and the characteristics of poorly protected areas were dependent on the difference in the two methods. Myocardium supplied by the right coronary artery seemed to be particularly vulnerable, and a special effort to protect these segments is mandatory for a successful outcome.

Increasing numbers of octogenarians are seen in the operating room or critical care unit with circumstances for which intraaortic balloon pump (IABP) assistance is appropriate, but it has been suggested that the complication rate for IABP use in octogenarians is excessive. From 1980 to 1990, 25 octogenarians needed an IABP in our institution, as an adjunct to operation in 20 patients (1 had repair of a ventricular rupture and 19 underwent coronary grafting); 5 patients did not have operation. The indications for IABP use were unstable angina, 12 (48%); cardiogenic shock, 10 (40%); and difficulty weaning off cardiopulmonary bypass, 3 (12%)--these 3 were the only ones who had insertion through a femoral cut-down. No serious insertion difficulties were noticed with the percutaneous route in the other 22 patients. Without operation, 4 of 5 patients died in the hospital (80%), and the 5th died 2 years 8 months after discharge. After operation, there were two hospital deaths (10%) and two late deaths, neither from cardiac causes. A fatal outcome occurred in 6 of 9 patients with cardiogenic shock. Intraaortic balloon pump-related complications were rare, minor, and unrelated to IABP assistance duration, which ranged from 24 to 146 hours (mean, 49.9 hours). No long-term vascular complications resulted. Hospital stay averaged 22.2 days. At follow-up from 9 to 81 months (mean, 51.8 months), of the 16 survivors, 12 (75%) were in New York Heart Association class I/II and 2 each were in classes III and IV.(ABSTRACT TRUNCATED AT 250 WORDS)

We report 5 cases in which intraoperative transesophageal echocardiography was instrumental in the early detection of a left ventricular wall-motion abnormality caused by acute dysfunction of a coronary artery bypass graft. The appearance of a wall-motion abnormality on transesophageal echocardiography preceded signs of myocardial ischemia when such signs were detectable with routine monitoring. By facilitating prompt, appropriate correction of technical problems, transesophageal echocardiography enabled the blood flow to be restored and the ischemic insult to be resolved without further complication.

The sheep model has been widely accepted for evaluating the in vivo performance of artificial valves. Introduction of transthoracic echocardiography revolutionized the evaluation of human cardiac valves, but in many cases, resolution of transthoracic studies in sheep is inadequate. The authors used transesophageal echocardiography to follow the performance of chronically implanted mitral prostheses. The technique has proven feasible and safe, requiring sedation only and being done in the spontaneously breathing animal without endotracheal intubation in the left lateral position. The HP 77020A, equipped with a standard HP 5 mHz transesophageal transducer probe, is used. The authors have had to modify the probe to allow for automatic cooling. Standard insertion techniques are used and the probe is positioned in the stomach, close to the gastroesophageal junction. They were able to assess leaflet motion, vegetations, and calcification and use color flow doppler to evaluate stenosis and regurgitation. The technique is convenient and permits a complete assessment of valve function in 10 minutes. Reproducibility has been confirmed. Validation of quantitative data will require further study.

This study was performed to clarify the location of a transesophageal echocardiographic (TEE) transducer when obtaining the short-axis view of the left ventricle (S-LV). The depth of the probe tip from the incisors when obtaining a S-LV, the relationship to the diaphragm, and the location of the cardia of the stomach using a gastroscope attached to the TEE probe were measured in 24 patients undergoing coronary artery bypass grafting. The location of the transducer relative to the cardia and diaphragm was determined. The study demonstrated that when obtaining a S-LV, the transducer was in the stomach in 72.7%, at the cardia in 13.6%, and in the esophagus in 13.6% of the patients. The predominantly intragastric position of the transducer suggests that gastric diseases should be included as contraindications to TEE. When the probe was advanced about 40 cm from the incisors, some resistance was often encountered by the TEE operator at about the level of the diaphragm. Careful manipulation is mandatory to avoid tissue damage by the probe. Visualization of the S-LV can be disturbed by gas in the stomach. This is a specific problem in anesthetized patients because gas is often pushed into the stomach at the time of induction.

Nitrogen balance and thymic immune function studies were carried out in rats subjected to anesthesia, jugular vein catheterization, and bilateral femoral fractures, who were then given for 5 days: A) D5W; B) D20 FreAmine II (total arginine 1.55 gm/L); or C) D20 FreAmine III (4.05 gm of arginine/L). Administration of hypercaloric amino acid mixtures had strong positive effects on nitrogen retention and thymic function when compared to isotonic dextrose infusion. The administration of solution C had the most positive effect on nitrogen balance and on thymic immune function. The data suggest that increased arginine administration may prove beneficial to injured patients.

The effect of 6-day dietary arginine supplementation on the weight gain, blood glucose, thymus weight, thymic lymphocyte content, and in vitro thymic lymphocyte immune reactivity was studied in obese (C57BL/6J-OB/)B) and heterozygous lean mice. Control mice were fed a commercial laboratory chow (1.8% arginine content) and drank tap water, while supplemented mice were given 0.5% arginine in the chow and 0.5% arginine solution for drinking. All mice ate and drank ad libitum. Supplemental arginine significantly decreased the weight gain (1.2 g vs. 2.2 g, p less than 0.01) and blood glucose levels (303 mg% vs 236 mg%, p less than 0.02) of the OB/OB mice; no such effects were noted in the lean heterozygotes, all of which had normal blood glucose levels. OB/OB mice had thymus glands which weighed less and contained significantly fewer lymphocytes than their lean littermates. In vitro mitogen-stimulated thymic lymphocyte protein synthetic rates were equal in chow-fed lean and OB/OB mice. In both groups, supplemental arginine significantly increased thymus weight, the number of thymic lymphocytes per gland, and thymic lymphocyte immunoreactivity in vitro. The hormonal secretagogue activity of arginine on the pituitary may explain its beneficial effects on the rate of weight gain, hyperglycemia, and depressed thymic immune function of OB/OB mice.

Retained intracardiac air is a continuing hazard for cardiopulmonary bypass. M-mode transesophageal echocardiography of the left atrium, left ventricle, and aorta is a highly sensitive method for detecting retained intracardiac air bubbles. In 15 patients having valve operations and 18 having coronary bypass, M-mode transesophageal echocardiography was used to record air bubbles during and for 15 minutes after bypass. Routine air clearing methods were used: needle aspiration of the ascending aorta (combined coronary and valve operations) and left atrial, left ventricular, and aortic aspiration after careful passive chamber filling (valve operations). Air was detected in 12 of 15 (79%) patients having valve operations and two of 18 (11%) patients having coronary bypass. One with air in the aorta had visible right coronary air embolism. Three patients with positive echograms had transient central nervous system disturbances. In a further 11 patients having valve operations, an ascending aorta-venous shunt was created before bypass was discontinued, but air continued to be present in the left atrium. Finally, in seven patients, we added the following maneuvers to our routine: positive chamber filling with echocardiographic demonstration of left atrial stretching, vigorous chamber ballottement, specific echo-directed chamber aspiration, and maintenance of cardiopulmonary bypass until transesophageal echocardiography showed no retained air. Although small amounts of atrial air could still be detected for a minute or two in some patients, this technique appears finally to have eliminated significant retained air and its consequences. A sensitive technique for intracardiac air detection reveals retained air surprisingly often after cardiopulmonary bypass. There are both possible and probable adverse consequences of this air. After valve operations, it is most difficult to eliminate air from the left atrium. There are three essential elements of air removal: First is mobilization of the air; positive chamber filling, stretching of the atrial wall, and ballottement are critical. Second is removal of mobilized air; continuous ascending aorta-venous shunting and nonsuction venting of the left atrium are very important. Third is proof of elimination of air before cardiopulmonary bypass is terminated; transesophageal echocardiography is vital for this.

The scarcity of donor lungs for transplantation has been caused, in part, by the belief that a single donor cannot provide usable lungs if it serves as a heart donor. However, the appropriate division of the left atrial wall provides sufficient cuffs for individual transplantation of the heart and each lung into three separate recipients. With the described technique, the results of the present studies demonstrate the feasibility of donor lung procurement and preservation for transplantation after cardiac donation. Use of this method will allow the most effective and efficient use of the limited supply of donor organs and thereby permit therapeutic single lung transplantation in selected patients. Cardiac donation should no longer preclude lung donation as it has in the past.

To maximize organ utilization, we assessed the feasibility of retrieving the heart and two single lungs or the heart and a separate bilateral lung block for transplantation into multiple recipients. In eight dogs the excision of the heart-lung block or of the left lung was followed by six hours of lung preservation. Four of these lungs and all eight hearts were transplanted successfully. In addition, satisfactory retrieval of the three separate organs or of the heart and a separate bilateral lung block was done in six human cadavers. An appropriate division of the left atrial wall provided suitable cuffs for individual transplantation of the three organs or for the heart and bilateral lung block. This study demonstrates the feasibility of multiple organ donation from a single donor followed by separate organ transplantation.

Various arginine HCl supplements (0.5-3%), half added to a basal commercial rodent chow (1.8% arginine) and half to the drinking water, were given to 8- to 9-week-old male CBA/J mice for 6 days. Control animals were fed the basal chow and drank tap water. All mice ate and drank ad libitum. Weight gain and food intake were similar in all groups. All arginine supplements increased significantly: thymic weight (average 22%), thymic lymphocyte content (average 45%), and the in vitro reactivity of thymic lymphocytes judged by the incorporation of 3H-leucine into the TCA-precipitable protein fraction in response to stimulation by phytohemagglutinin and concanavalin A. All these thymic effects resulted from the 0.5% arginine hydrochloride supplement; further increases in arginine supplementation did not increase these effects. These data suggest that supplemental arginine may improve host defence mechanisms and thereby may play an important role in the care of severely injured or ill patients, since it is well established that their defense mechanisms are reduced.