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OBJECTIVE Pig-to-primate renal xenotransplantation is plagued by early antibody-mediated graft loss which precludes clinical application of renal xenotransplantation. We evaluated whether temporary complement inhibition with anti-C5 antibody Tesidolumab could minimize the impact of early antibody-mediated rejection in rhesus monkeys receiving pig kidneys receiving costimulatory blockade-based immunosuppression. METHODS Double (Gal and Sda) and triple xenoantigen (Gal, Sda, and SLA I) pigs were created using CRISPR/Cas. Kidneys from DKO and TKO pigs were transplanted into rhesus monkeys that had the least reactive crossmatches. Recipients received anti-C5 antibody weekly for 70 days, and T cell depletion, anti-CD154, mycophenolic acid, and steroids as baseline immunosuppression (n = 7). Control recipients did not receive anti-C5 therapy (n = 10). RESULTS Temporary anti-C5 therapy reduced early graft loss secondary to antibody-mediated rejection and improved graft survival (P < 0.01). Deleting class I MHC (SLA I) in donor pigs did not ameliorate early antibody-mediated rejection (table). Anti-C5 therapy did not allow for the use of tacrolimus instead of anti-CD154 (table), prolonging survival to a maximum of 62 days. CONCLUSION Inhibition of the C5 complement subunit prolongs renal xenotransplant survival in a pig to non-human primate model.

Objective To present a case that demonstrates the evolution of a pheochromocytoma over a several-year period and to emphasize the importance of a thorough work-up for pheochromocytoma in patients with neurofibromatosis type 1 (NF1) and hypertension. Methods We review the long-term clinical, biochemical, and imaging findings in a man with a complex medical history of hypertension, NF1, and cardiomyopathy. Results A 44-year-old man, with a well-documented history of headaches, hypertension, and NF1, was referred for evaluation of a right adrenal enlargement. He had developed cardiomyopathy and undergone an evaluation for cardiac transplantation. Initial computed tomography revealed subtle asymmetry in the upper right adrenal gland. Biochemical studies for pheochromocytoma yielded equivocal findings, with a 1.5-fold elevation in the urinary norepinephrine and near-normal urinary metanephrine level. Because 131I-metaiodobenzylguanidine imaging showed no tracer uptake in the area of the right adrenal gland, the patient was thought not to have a pheochromocytoma. The patient eventually underwent cardiac transplantation and did well. On reassessment 3 1/2 years later, he was found to have a larger right adrenal mass. The second endocrine evaluation demonstrated substantial elevation in the urinary metanephrine level, and the patient underwent laparoscopic right adrenalectomy to remove the tumor (3.5 by 3.0 by 2.5 cm), which proved to be a pheochromocytoma. Conclusion This case shows that a pheochromocytoma can be difficult to diagnose and can evolve to become a large, biochemically active tumor. It is imperative that patients with an adrenal tumor undergo periodic reevaluation to ensure that the tumor remains stable in size. If the tumor enlarges, further biochemical testing is warranted.

Objective The REMATCH trial compared the use of left ventricular assist devices with optimal medical management for patients with end-stage heart failure. When the trial met its primary end point criteria in July 2001, left ventricular assist device therapy was shown to significantly improve survival and quality of life. With extended follow-up, 2 critical questions emerge: (1) Did these benefits persist, and (2) did outcomes improve over the course of the trial, given the evolving nature of the technology? Methods We analyzed survival in this randomized trial by using the product-limit method of Kaplan and Meier. Changes in the benefits of therapy were analyzed by examining the effect of the enrollment period. Results The survival rates for patients receiving left ventricular assist devices (n = 68) versus patients receiving optimal medical management (n = 61) were 52% versus 28% at 1 year and 29% versus 13% at 2 years ( P = .008, log-rank test). As of July 2003, 11 patients were alive on left ventricular assist device support out of a total 16 survivors (including 3 patients receiving optimal medical management who crossed over to left ventricular assist device therapy). There was a significant improvement in survival for left ventricular assist device–supported patients who enrolled during the second half of the trial compared with the first half ( P = .03). The Minnesota Living with Heart Failure scores improved significantly over the course of the trial. Conclusion The extended follow-up confirms the initial observation that left ventricular assist device therapy renders significant survival and quality-of-life benefits compared with optimal medical management for patients with end-stage heart failure. Furthermore, we observed an improvement in the survival of patients receiving left ventricular assist devices over the course of the trial, suggesting the effect of greater clinical experience.

Background Left ventricular assist device (LVAD) failure and malfunction rates are critical gauges for establishing LVADs as a long-term therapy for end-stage heart failure patients. These device performance measures, however, have been inadequately characterized in the bridge-to-transplantation literature. Methods REMATCH is a randomized trial that compares optimal medical management with LVAD implantation for patients with end-stage heart failure. An independent committee adjudicated patient outcomes. The primary endpoint—survival—was analyzed by intention to treat using the log-rank statistic. Frequency of event occurrence was analyzed by Poisson regression. The time to first event was analyzed by the product limit method. Device performance was disaggregated into confirmed malfunctions and system failures. The latter were events in which patients could not be rescued with backup circulatory support measures. Results The 1-year survival rate was 52% (95% confidence limit [CL]; 40%–63%) for LVAD patients versus 28% (95% CL; 17%–39%) for medical patients and the 2-year survival rate was 29% (95% CL; 19%–40%) for LVAD patients versus 13% (95% CL; 5%–22%) for medical patients. System failure was 0.13 per patient per year and the confirmed LVAD malfunction rate was 0.90. Freedom from device replacement was 87% at 1 year and 37% at 2 years. Conclusions Despite the observed rates of device malfunction and replacement, LVAD implantation confers clinically significant improvement with regard to survival as compared with medical management. Device modifications and innovations for infection management exhibit great promise of improving device performance in the near future.

Objective: The HeartMate® VE left ventricular assist system (LVAS) has supported more than 2300 patients and has been shown to be effective for bridge to cardiac transplantation and has demonstrated improved outcomes in survival as a destination therapy. Improvements in device durability are needed as bridge to transplant times increase and as we move into the era of LVAD as destination therapy. The purpose of this study is to determine if design enhancements to the HeartMate LVAS have improved device reliability and durability. Methods: A retrospective analysis of serious mechanical failures was performed in 1865 devices (1458 VE, 407 XVE). The analysis of data included devices used to support patients from September 1998 for bridge to transplantation and destination therapy. Serious mechanical failures were defined as inflow valve dysfunction, percutaneous lead breaks, diaphragm fractures or punctures, bearing failures, outflow graft erosion and pump disconnects. Results: Median device duration for the VE was 97 days (max 1206 days), and 85 days (max 517 days) for the XVE. A total of 134 serious mechanical failures occurred and included inflow valve dysfunction (5.3% VE, 2.4% XVE) (P = 0.853), percutaneous lead breaks (1.9% VE, 0% XVE) (P < 0.001), diaphragm fractures (0.1% VE, 0% XVE) (P = 0.134), outflow graft erosion (0.2% VE, 0% XVE) (P = 0.1096), pump disconnects (0.1% VE, 0% XVE) (P = 0.1336) and bearing failures (0.6% VE, 0.2% XVE) (P = 0.5538). Of the XVEs 97% were free of serious mechanical failures at 6 months and 82% at 1 year compared to 92 and 73% for the VE, respectively. The 6-month difference between the devices was statistically significant (P = 0.0063) and there was no statistically significant difference at 1 year (P = 0.1492). Conclusions: Preliminary experience with the HeartMate XVE LVAS demonstrated a significant reduction in percutaneous lead breaks. Early trends indicate positive impact of recent design modifications on XVE performance. These design modifications may improve device durability and reliability, which is crucial as we enter the era of LVADs as an alternative to medical therapy.

Background . Most of our patients with coronary artery disease have undergone bypass exclusively with purely internal thoracic artery grafts (PITA). Our goal has been to lengthen the time a patient benefits from coronary bypass operations. The present report describes an 8.5-year study of outcomes including mortality and the need for reintervention in patients who have undergone bypass with PITA. Methods . We studied 897 patients who underwent PITA with a total of 3,784 internal thoracic artery (ITA) grafts (4.2 grafts per patient). Connecting ITA to ITA along with sequential anastomosis made the procedure possible. Results . Early mortality for the group was 2.3%. Freedom from death was 86% and freedom from reintervention was 94% at 5 years after the operation. Conclusions . The acceptable early and late mortality and the 94% freedom from reintervention as long as 8.5 years after operation in this group of patients inspire us to continue choosing PITA for patients with three-vessel coronary artery disease.

CTLA-4 is an immunoregulatory receptor expressed on the surface of activated T and B lymphocytes. The counterreceptors for CTLA-4 are the B7 family molecules. We describe alternatively spliced mRNAs expressed in hematolymphoid tissues of humans, mice, and rats that lack the transmembrane domain coded by exon 3 of the CTLA-4 gene. These alternate transcripts were detected by RT-PCR in B cells and resting T cells of both the CD4 and the CD8 phenotype. Activation of human blood mononuclear cells with PHA or anti-CD3 + anti-CD28 monoclonal antibodies appears to effect a decrease in the amount of the alternative transcript relative to the full-length transcript. Recombinant sCTLA-4 is a B7-binding protein and has immunomodulatory effects as measured by inhibition of the mixed leukocyte response. Human serum contains immunoreactive material consistent with a native soluble form of CTLA-4.

Background . Safe transition from cardiopulmonary bypass to the HeartMate left ventricular assist device without periods of low output, air emboli, or injury to the right ventricle is vital to its successful implantation. A right atrial-to-left ventricular shunt has been developed to purge quickly and completely all air from the system and prevent its reentry, as well as to assist the right ventricle during the transition from cardiopulmonary bypass to the HeartMate. Methods . From January 1994 through July 1996, we used an extracorporeal membrane oxygenation right atrial-to-left ventricular shunt during 17 HeartMate implantations in 16 patients. The shunt consists of the existing right atrial two-stage cannula, the bypass circuit, and a separate aortic line that fills the left ventricle using a 21F cannula in the lateral ventricular wall. Air is monitored in the heart and aorta using transesophageal echocardiography. Results . Ten of the 16 patients are living and 8 have undergone transplantation. Two patients are still using the device and are awaiting transplantation. None of the patients have experienced postoperative neurologic events suggestive of air emboli. Conclusions . The extracorporeal membrane oxygenation right atrial-to-left ventricular shunt is simple and inexpensive to construct. It provides for a smoother and safer transition from cardiopulmonary bypass to the HeartMate left ventricular assist device.

Rat strains with congenitally reduced total hemolytic complement activity do not reject cardiac xenografts hyperacutely. Prolongation of graft survival in the guinea pig-to-C6-deficient PVG rat donor/recipient combination has been observed. However, experience with this model has been complicated by a high postoperative mortality from respiratory distress. The authors hypothesized that placement of the xenograft resulted in local activation of complement, which contributed to remote pulmonary injury leading to respiratory dysfunction. To test this hypothesis, an attempt was made to reduce early complement component activation with the use of an antibody to rat C3 in C6-deficient PVG recipients. Six of eight untreated C6-deficient PVG recipients died in the immediate postoperative period with vigorously beating heart grafts, whereas only 2 of 14 C6-deficient recipients pretreated with anti-rat C3 antibody died within 24 h postoperatively. Although pretreatment with anti-C3 antibody improved survival of recipients, the duration of cardiac xenograft survival was similar whether the recipients were pretreated or not. The use of anti-C3 antibody in C6-deficient rats is a valid approach to studying xenotransplantation in the absence of hyperacute rejection and has an additional advantage in that it does not require the use of expensive reagents such as cobra venom factor.

We compared the survival outcomes, left ventricular assist device (LVAD)-related hospitalization, stroke, infection, panel reactive antibody, and blood product use data among 13 Novacor and 51 HeartMate system recipients. Stroke was significantly higher in Novacor patients, as was blood product use at the time of heart transplantation, likely due to long-term anti-coagulation, while the LVAD-related hospitalization and infections did not differ between the 2 groups. A positive panel reactive antibody was seen more among the HeartMate patients, but did not have a significant clinical impact and may not represent a true allosensitization.

We used reverse transcription-polymerase chain reaction (RT-PCR) to clone a rat complementary DNA that encoded the PVG rat granulocyte-macrophage colony-stimulating factor (GM-CSF). PCR products were cloned into a eukaryotic expression vector and transfected into the mouse myeloma cell line Sp2/0-Ag14. Cell culture supernatants of two of these transfectants supported proliferation of the growth factor-dependent cell line, DA-3, and promoted myeloid colony formation in rat and mouse bone marrow cell (BMC) cultures. The GM-CSF activity in these supernatants was neutralized by a polyclonal antibody to mouse GM-CSF. The cloning and expression of rat GM-CSF provides a valuable reagent for the study of the biology and clinical applications of the GM-CSFs.

Selection of the bypass graft that the patient has demonstrated will remain patent and free from critical atherosclerosis is a most important part of coronary artery bypass reoperations. Sixteen patients in whom a patent left internal thoracic artery—left anterior descending coronary artery bypass graft and obstructed or closed saphenous vein grafts to other coronary arteries were visualized underwent reoperation. To reach the inadequately perfused circumflex and right coronary arteries, the right internal thoracic artery was anastomosed to the left internal thoracic artery as a T graft and then was attached to the circumflex and right coronary artery branches. All patients survived the procedure and are free from angina. There were no perioperative myocardial infarctions, and there was no suggestion of hypoperfusion by the grafts. We believe this technique may reduce the incidence of graft failure in patients undergoing reoperative coronary artery bypass grafting.

Background. Little is known about the clonality of Staphylococcus epidermidis in the United States, although it is the predominant pathogen in infections involving prosthetic materials, including ventricular assist devices (VADs). Methods. Seventy-five VAD recipients at 4 geographically diverse US cardiac centers were prospectively followed up to 1 year of VAD support. The anterior nares, sternum, and (future) driveline exit site were cultured for S. epidermidis before VAD insertion and at 7 times after surgery. Infection isolates were also collected. Isolates were typed by pulsed-field gel electrophoresis. A subset underwent susceptibility testing and staphylococcal chromosomal cassette mec and multilocus sequence typing. Results. A total of 1559 cultures yielded 565 S. epidermidis isolates; 254 of 548 typed isolates (46%) belonged to 1 of 7 clonal types as defined by pulsed-field gel electrophoresis. These clones were identified in up to 27 people distributed across all 4 cardiac centers. They caused 3 of 6 VAD-related infections. Disseminated clones were more antibiotic resistant than were less prevalent isolates (eg, 79% vs 54% methicillin resistant; P 5 .0021). Conclusions. This study revealed that healthcare‐associated S. epidermidis infection is remarkably clonal. We describe S. epidermidis clones that are highly resistant to antibiotics distributed across US cardiac centers. These clones may have determinants that enhance transmissibility, persistence, or invasiveness. Clinical Trials Registration. NCT01471795.

Background Given the large number of patients undergoing cardiac operations annually, it is important to identify populations at high risk for adverse outcomes. This observational study was conducted to determine the incidence of preoperative heparin-platelet factor 4 (HPF4) antibodies and to assess the associated risk of postoperative adverse outcomes in a nonselected cardiac surgery patient population. Methods Between March 2002 and December 2004, 1114 (92%) of 1209 patients undergoing cardiac surgery with heparin were tested in an unselected manner for HPF4 antibodies. Main outcome measures were HPF4 antibody seropositivity and fatal and nonfatal adverse clinical outcomes after cardiac surgery. Results Of those screened, 60 (5.4%) of 1114 had positive HPF4 antibodies preoperatively. These patients had longer mean postoperative length of stay (14.0 days versus 9.8 days, p = 0.05), a higher incidence of prolonged (≥96 hours) mechanical ventilation (20.3% versus 9.2%, p = 0.02), acute limb ischemia (5.1% versus 0.9%, p = 0.03), renal complications including dialysis (20.3% versus 10.5%, p = 0.03), and gastrointestinal complications (15.3% versus 5.9%, p = 0.01). Stepwise logistic regression analysis showed positive HPF4 antibody status to be an independent predictor for adverse outcome and was associated with a higher risk for renal complications, including dialysis (adjusted odds ratio 2.2; 95% confidence interval, 1.1 to 4.3), than was diabetes. Conclusions In this large patient series, the presence of HPF4 antibodies before surgical heparin administration was an independent and clinically significant risk factor for postoperative adverse events after cardiac surgery. An optimal preoperative cardiac surgery risk profile should include HPF4 antibody status.

Introduction. CTLA-4 is a negative regulatory molecule upregulated on activated T cells; however, its role in induction and maintenance of transplant tolerance is not well understood. Methods. The characteristics and effects of a novel mouse anti-rat CTLA-4 antibody (Ab) (242B58) were examined using fluorescence-activated cell sorter, mixed lymphocyte reaction, enzyme-linked immunospot, signaling studies, and a rat model of cardiac transplant tolerance induced by administration of anti-CD28 Ab and cyclosporine. Results. The anti-CTLA4 Ab was shown to bind to CTLA-4 but not prevent subsequent binding of B7 to CTLA-4. Binding to CTLA-4 did not result in phosphorylation of early cytoplasmic tyrosine kinases, suggesting that this is not a signaling Ab. However, its in vitro function was compatible with antagonization of the effects of CTLA-4, thereby increasing T-cell proliferation and interferon-gamma production in mixed lymphocyte reaction and enzyme-linked immunospot assays, respectively. Administration of 242B58 to animals treated with anti-CD28 Ab and cyclosporine either at the time of transplantation or various time-points up to 33 days posttransplantation did not result in immediate rejection, but rather caused a delayed severe acute allograft rejection at approximately 45 days posttransplant. Conclusions. Our results seem to be a reflection of the unique properties of the 242B58 Ab, which does not antagonize B7 binding to CTLA-4 and affect its ability to out-compete CD28 for B7 binding. It does, however, seem to interfere with CTLA-4 signaling, suggesting that competition for B7 may be important in induction of tolerance, but signaling through CTLA-4 is more important in maintaining a tolerant phenotype.

This article describes the development of a new experimental model using rats for the evaluation of small-caliber vascular grafts. By modifying heterotopic heart transplantation, two 1.5- to 2.0-cm long vascular prostheses were interposed between a syngeneic donor heart and the recipient abdominal vessels in the form of vascular bridges. Once blood flow through the vascular grafts was reestablished, the donor heart resumed normal beating. The status of the vascular grafts could be easily monitored by palpation. Occlusion of the grafts stopped donor heart beating without affecting survival of the animals. Once the surgical method was mastered, the postoperative mortality was approximately 10%, and the total procedure took less than 2 hours. Although microvascular surgical technique and equipment are required, this model has several advantages, including easy detection of thrombotic occlusion of the grafts, the use of small animals of defined genetic background, the absence of effect of graft occlusion on the recipient's life, and possible repeated operation on the same animal.

OBJECTIVE: This nonrandomized study using concurrent controls was performed to determine whether the HeartMate implantable pneumatic (IP) left ventricular assist system (LVAS) could provide sufficient hemodynamic support to allow rehabilitation of severely debilitated transplant candidates and to evaluate whether such support reduced mortality before and after transplantation. METHODS: Outcomes of 75 LVAS patients were compared with outcomes of 33 control patients (not treated with an LVAS) at 17 centers in the United States. All patients were transplant candidates who met the following hemodynamic criteria: pulmonary capillary wedge pressure > or = 20 mm Hg with a systolic blood pressure < or = 80 mm Hg or a cardiac index < or = 2.0 L/minute/m2. In addition, none of the patients met predetermined exclusion criteria. RESULTS: More LVAS patients than control patients survived to transplantation: 53 (71%) versus 12 (36%) (p = 0.001); and more LVAS patients were alive at 1 year: 48 (91%) versus 8 (67%) (p = 0.0001). The time to transplantation was longer in the group supported with the LVAS (average, 76 days; range, < 1-344 days) than in the control group (average, 12 days; range, 1-72 days). In the LVAS group, the average pump index (2.77 L/minute/m2) throughout support was 50% greater than the corresponding cardiac index (1.86 L/minute/m2) at implantation (p = 0.0001). In addition, 58% of LVAS patients with renal dysfunction survived, compared with 16% of the control patients (p < 0.001). CONCLUSIONS: The LVAS provided adequate hemodynamic support and was effective in rehabilitating patients based on improved renal, hepatic, and physical capacity assessments over time. In the LVAS group, pretransplant mortality decreased by 55%, and the probability of surviving 1 year after transplant was significantly greater than in the control group (90% vs. 67%, p = 0.03). Thus, the HeartMate IP LVAS proved safe and effective as a bridge to transplant and decreased the risk of death for patients waiting for transplantation.

Intragraft T-cell receptor (TCR) alpha and beta chain variable region gene expression was analyzed in human cardiac allograft biopsies by reverse transcription polymerase chain reaction. Rearranged TCR alpha and beta chain gene transcripts were detected in all biopsies examined (N = 23), indicating the presence of T cells bearing the alpha/beta TCR even in the absence of microscopically apparent leukocyte infiltration. In this analysis, a broad TCR alpha/beta repertoire in actively rejecting lesions was demonstrated, whereas fewer TCR alpha and beta chain gene families were detected in nonrejecting lesions. The number of expressed TCR V beta chain gene families typically was two- to sixfold higher than that of V alpha chain families in all biopsies tested. This asymmetric relation was present throughout the histologic grading spectrum of the biopsies. Based on these data, the TCR repertoire is heterogenous even in the early stages of mononuclear cell infiltration of the allograft. Also based on the data, the presence of T cells in grafts with minimal cellular infiltrates is not a specific marker of subsequent rejection episode, because T cells were identified in all allograft biopsies.

the risk of CAV in subjects treated with CNI/AZA (HR-2.33, CI -1.06-5.0, p 0.035; n 160) but not in CNI/MMF (HR -1.49, CI 0.26-7.71, p 0.64; n 59) or in sirolimus (as primary immunosuppressant) treated subjects (HR 0.13, CI 0.001-2.55, p 0.13, n 33). In multivariate analysis 6-month TRS (HR 2.84, CI1.44-6.91, p 0.02) and 6-month MRS (HR-2.66, CI-0.99-6.95, p 0.05) remained significant predictors of increased risk for CAV onset. Twelve and 24 months rejection scores were not risk factors for the onset of CAV. By Kaplan-Meier analysis 6month TRS 0.3 was associated with a significantly shorter time to CAV onset (p 0.018). There was no association between TRS and MRS and 3D IVUS criteria but 38% of this group were treated with sirolimus and 69% with MMF. Conclusions: Increased episodes of rejection in the first 6 months in subjects treated with CNI and AZA increases risk of CAV. Lack of association between rejection score and CAV, assessed agiographically and by 3D IVUS in patients treated with MMF and sirolimus suggests that this combination of immunosuppressive agents may result in improvement in the long-term outcome of CAV.

A series of 142 adult patients undergoing open-heart surgery were studied. All known blood-conservativing methods were utilized in an attempt to use as little blood as possible. Hemodilution, autologous transfusion, prevention of wasting of blood, and management of postoperative anemia were the measures employed. An average of 2.66 units of blood were given per patient during the entire hospital stay. Twenty patients were not given any blood at all. The patients were removed from cardiopulmonary bypass without difficulty when the hematocrit reading was in the high teens or low twenties. Later in the postoperative period the patients seemed to progress without difficulty with hematocrit readings of 22 to 25 percent.

The internal mammary artery (IMA) was used as a graft in 298 patients undergoing coronary bypass procedures. Two patients died during the operative period and 2 others died one year later. Most of the survivors are free of angina. Of the IMAs restudied 9 to 24 months postoperatively, 95% were patent. This group included nearly all the patients having angina after operation. There are some situations in which the IMA may have inadequate flow in comparison to the vein graft. These results suggest the IMA is an excellent graft in most coronary bypass procedures.

The results of isolated mitral valve replacement with the Bjork-Shiley disc prosthesis from 1970 to 1973 were compared with those obtained with the cloth-covered Starr-Edwards valve (Models 6300 and 6310) between 1968 and 1971. The patients in both series were followed from 6 to 42 months postoperatively. Hospital mortality rate with the disc prosthesis was 3.6 per cent as opposed to 23.8 per cent with the ball valve, but this difference might be due mainly to the improvement in intraoperative and postoperative care initiated after the ball-valve series was concluded. Fewer late deaths (6.6 versus 15 per cent), thromboembolic complications (4.7 versus 9 per cent), and a better quality of life among survivors were observed with the disc prosthesis, although there was no statistical significance. Prosthetic infection occurred in eight (12 per cent) of the ball valves and only in one (0.9 per cent) of the disc valves (p

Subendocardial flow was measured as a temperature differential between the epicardium and the subendocardium during cardiopulmonary bypass by a measured bolus of cold blood of known temperature injected into the aortic root. The probes, with 0.1 second time response, were accurately placed in the subendocardium and the subepicardium, equidistant from the nearest coronary vessel. The least change recorded was 0.015° C. Direct-current operational amplifier offset the basal temperature, which was measured by a separate probe and maintained constant by small variations from the heat exchanger. Subendocardial and subepicardial flows were recorded in 20 dogs at constant aortic root pressures in the empty, beating and the empty, fibrillating heart. The effects of varying the aortic root pressures on the subendocardial and subepicardial flow ratios were studied in the empty, beating and empty, fibrillating heart. At all pressures studied, the endocardial-epicardial ratio was significantly lower for the empty, fibrillating than for the empty, beating heart (p

A case of multiple cardiac injuries secondary to a single stab wound is described. The extent of the injury was not fully appreciated at the initial surgical intervention and typical clinical manifestations were delayed in appearance. Cardiac catheterization was necessary to confirm the correct diagnosis. After the correct diagnosis was made, surgical repair was successfully performed. Language: en

A case report of a traumatic tear of the aortic arch with a successful surgical repair is presented. The surgical techniques used in the management of this unusual injury are described, and the principles of cerebral perfusion are discussed.

Initially, the internal mammary artery (IMA) was implanted into the myocardium, and 10 years later it was anastomosed directly to coronary arteries. Our experience with the IMA started with single attached grafts. To reduce injury to the pedicle and improve anastomotic accuracy, magnification, microsurgical techniques, and cardioplegia were introduced. After establishing excellent long-term patency of the IMA and knowing of the high incidence of obstruction in saphenous vein grafts 7 to 10 years after operation, we hypothesized that multiple IMA coronary anastomoses could improve the long-term results of coronary artery bypass grafting. Bilateral IMA, sequential IMA, and IMA Y-grafts were used to increase the number of mammary coronary anastomoses to 3.1 per patient. Early clinical results and patency evaluations are encouraging. In our experience, the IMA has evolved from being implanted into the myocardium, to a single bypass graft to the left anterior descending coronary artery, and finally to being the bypass conduit of choice supplying blood to three or more obstructed coronary arteries or their branches.

To improve (he early and late benefits from coronary artery bypass grafting, we have expanded the use of the internal mammary artery by bypassing three or more coronary arteries with mammary grafts. Experience with higher power magnification and the use of the single internal mammary artery are necessary prerequisites of this procedure. The first 100 patients who had three or more mammary artery–coronary artery anastomoses are reviewed. Eighty-six patients received three mammary-coronary anastomoses, 13 received four, and one received six. An average of 3.2 internal mammary artery grafts and 1.7 saphenous vein grafts per patient were placed. Twenty-five of 27 mammary grafts were open on postoperative graft visualization. There were no early deaths and only one patient died late of complications of gangrene of the lower extremities. None of the patients had significant left ventricular failure and only three had perioperative myocardial infarctions. None of the patients complain of angina and 58 of 59 postoperative stress tests were normal. This procedure should significantly reduce the late closure of bypass grafts and the complications thereof, including the need for reoperation.

Long-term patency of the internal mammary artery graft surpasses that of all other bypass conduits. The use of multiple internal mammary artery grafts should improve the long-term results following coronary artery bypass grafting. Technical factors used in mobilizing, preparing, and anastomosing the internal mammary artery are discussed in this article. Fifty-three patients received sequential attached left internal mammary artery grafts from April, 1982, to August, 1983. In 6 of these patients, the right internal mammary artery was anastomosed to a circumflex marginal branch. There were no operative deaths or instances of low cardiac output. One patient suffered anastomotic narrowing that possibly could have been prevented by excision of excess tissue from the internal mammary artery pedicle. Multiple internal mammary artery grafting should have a profound influence on the results of coronary artery bypass grafting.

Percutaneous transluminal coronary angioplasty (PTCA) has been used to treat patients with prior coronary artery bypass grafting who have stenosis of a saphenous vein graft and/or a native artery. During 53 months, 61 patients underwent 105 angioplasty attempts. Eighty lesions (76%) were successfully dilated in 46 of 61 patients (75 %). Success in a patient was determined by a ≥20% decrease in the percent diameter stenoses coupled with an improved clinical response; 52 patients had one prior CABG and nine patients had two or more prior CABGs. Multivessel disease was present in 56 patients (92%). A vein graft stenosis was successfully dilated in 26 of 33 cases (79%)—19 of 25 (76%) at an anastomotic site and seven of eight (88 %) in the graft body. An arterial stenosis was successfully dilated in 37 of 52 cases (71%)—18 of 22 (82%) in the left anterior descending, 13 of 22 (59%) in the circumflex, 21 of 26 (81 %) in the right coronary, and two (100%) in the left main coronary artery. There is no statistically significant difference in the incidence of success in dilating a vein graft or native artery. Complications included: one emergency CABG (1.6%), three myocardial infarctions (4.9%), and two deaths (3.3%). There were 15 unsuccessful PTCAs: Ten patients had elective CABG, one had emergency CABG, two received medical treatment, and two died. Forty-six patients are being followed-up: Twenty-eight (61 %) continue to do clinically well, seven (15%) had another PTCA and remain well and 10 (16%) had elective CABG because of restenosis and/or disease progression. There was one late death and one late myocardial infarction. Thus, 35 patients (57%) had continued clinical success without the need for repeat CABG; 89% had no angina or improved angina, and 90% had improved exercise treadmill results. PTCA is technically feasible in selected patients with prior CABG and can achieve a clinical response with an acceptable complication rate when compared to repeat CABG.

A new temporary pacemaker electrode, which leaves no exposed areas of wire when implanted, has been designed for use in postoperative cardiac surgical patients. The device, tested in 28 patients who underwent open-heart surgery, has significantly reduced the increase in myocardial threshold to pacing that occurs with the commonly used electrode. Sensing of the electrical signal has been excellent for demand pacing. We feel that this new electrode represents an improvement in the management of patients with postoperative arrhythmias.

A total of 205 adults with a variety of congenital heart lesions underwent operation for total correction of their defects. Operative and long-term mortality were 3 and 4 percent, respectively. There has been only one operative death in the past five years (85 patients). While most defects were repaired with good hemodynamic and symptomatic improvement, the three lesions associated with the worst results were cyanotic tetralogy of Fallot, severe pulmonic stenosis complicated by atrial septal defect, and ostium primum atrial septal defect. Myocardial failure due to end-stage myocardial fibrosis was the major cause of operative mortality. Myocardial fibrosis and irreversible pulmonary changes seemed to be the two factors limiting operative correction. An aggressive operative approach seems justified based on this study.

Data from three large groups of patients undergoing aorta-to-coronary artery saphenous vein bypass grafting with follow-up angiograms between 0 and 32 months and postoperative clinical evaluation for up to 46 months enable us to say there is an early saphenous vein closure rate of 9%. These closures are probably related to technical judgment difficulties and lend themselves to improvement in results. The documented late closure rate in 92 patients followed a mean of 31.7 months was 13%. This is a rate of one late closure per 171 patient-months. Of the 92 patients, 80 had some effective vein graft functioning in this follow-up period. Histological evaluation has revealed subintimal fibrous hyperplasia to be the predominant factor involved in late closure of the vein bypass. Its manifestations are variable, and the multifactorial etiology is as yet unclear. Since 5% of vein grafts have some significant subintimal fibrous hyperplasia at the time of insertion, only close follow-up with correlation of operative, angiographic, and histological data will provide the answers to the question of etiology of late vein graft closure. Studies on the effect of trauma, vascularity, and nutrition of vein grafts are necessary. The answer to this problem will be necessary to set the coronary vein bypass procedure on a firm footing in the treatment of coronary artery disease.

The results of combined valve replacement and coronary artery bypass in 13 patients are presented. The importance of preoperative coronary visualization in all adult patients undergoing valve replacement is emphasized. The techniques by which we have been able to carry out perfusion of the coronary arteries in these patients with coronary atherosclerosis is also demonstrated. The combined attack on both these problems should, with increasing skill, improve the results in patients with combined valve and coronary artery disease.

Objective The Levitronix CentriMag (Levitronix LLC, Waltham, Mass) ventricular assist system is designed for temporary left, right, or biventricular support. Advantages include ease of use, excellent reliability, and low thrombosis risk,. which may allow wider application of short-term support and improved outcomes in patients with cardiogenic shock. This multi-institutional study evaluated safety, effectiveness, and outcomes of the CentriMag in patients with cardiogenic shock. Methods Thirty-eight patients were supported at 7 centers. Patients included 12 after cardiotomy, 14 after myocardial infarction, and 12 with right ventricular failure after implantable left ventricular assist device placement. Devices were implanted in left (n = 8), right (n = 12), or biventricular (n = 18) configuration. Support was continued until recovery, transplantation, or implantation of long-term ventricular assist device. Results Mean support duration for the entire cohort (n = 38) was 13 days (1–60 days), with 47% of patients (18/38) surviving 30 days after device removal. Mean CentriMag biventricular support (n = 18) duration was 15 days (1–60 days), with 44% (8/18) surviving at 30 days. Mean CentriMag right ventricular support with a commercially available left ventricular assist device (n = 12) duration was 14 days (1–29 days), with 58% (7/12) surviving at 30 days. Complications included bleeding (21%), infection (5%), respiratory failure (3%), hemolysis (5%), and neurologic dysfunction (11%). There were no CentriMag or pump failures. Conclusions In this preliminary study, the CentriMag provided short-term support for patients with cardiogenic shock with a low incidence of device-related complications and no device failures.

The transverse sinus route for bypassing high marginal circumflex coronary arteries facilitates the operation and obviates potential kinking sites at the left atrial appendage and pericardial reflection over the pulmonary veins. The vein bypass emerges from the transverse sinus and closely parallels the marginal circumflex coronary vessels.