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Changes in left ventricular early diastolic time intervals are sensitive indicators of incipient left ventricular dysfunction. We tested the hypothesis that acute rejection in cardiac transplant recipients is associated with alteration of early diastolic myocardial function, as expressed by the time interval Te, a parameter derived from digitized M-mode echocardiograms. Te is defined as the time interval between maximal posterior wall contraction and the point of peak posterior wall endocardium retraction velocity, as determined by the nadir of the computed first derivative curve. In transplant patients without rejection (group A, n = 48), Te was prolonged compared to healthy individuals (group C, n = 35) (79.0 +/- 12.5 ms vs 64.0 +/- 7.9 ms; p < 0.0001). During acute rejection (group B, n = 18) transplant patients had significantly longer mean Te values compared to transplant patients without rejection (group A) (97.8 +/- 17.9 ms vs 79.0 +/- 12.5 ms; p < 0.0001). Longitudinal studies in individual patients (group D, n = 18) demonstrated that rejection is associated with prolongation of Te (94.5 +/- 16.0 ms during rejection vs 79.0 +/- 10.3 ms before rejection; p < 0.0002) and that Te returns to individual baseline values in response to treatment (79.2 +/- 9.4 ms after therapy vs 79.0 +/- 10.3 ms before rejection; NS). In a prospective study, Te changes in transplant patients (group E, n = 96) were correlated with myocardial biopsy results. Sixty-one biopsies showed acute rejection, and 115 biopsies were negative.(ABSTRACT TRUNCATED AT 250 WORDS)

Staphylococcus epidermidis remains the predominant pathogen in prosthetic-device infections. Ventricular assist devices, a recently developed form of therapy for end-stage congestive heart failure, have had considerable success. However, infections, most often caused by Staphylococcus epidermidis, have limited their long-term use. The transcutaneous driveline entry site acts as a potential portal of entry for bacteria, allowing development of either localized or systemic infections. A novel in vitro binding assay using explanted drivelines obtained from patients undergoing transplantation and a heterologous lactococcal system of surface protein expression were used to identify S. epidermidis surface components involved in the pathogenesis of driveline infections. Of the four components tested, SdrF, SdrG, PIA, and GehD, SdrF was identified as the primary ligand. SdrF adherence was mediated via its B domain attaching to host collagen deposited on the surface of the driveline. Antibodies directed against SdrF reduced adherence of S. epidermidis to the drivelines. SdrF was also found to adhere with high affinity to Dacron, the hydrophobic polymeric outer surface of drivelines. Solid phase binding assays showed that SdrF was also able to adhere to other hydrophobic artificial materials such as polystyrene. A murine model of infection was developed and used to test the role of SdrF during in vivo driveline infection. SdrF alone was able to mediate bacterial adherence to implanted drivelines. Anti-SdrF antibodies reduced S. epidermidis colonization of implanted drivelines. SdrF appears to play a key role in the initiation of ventricular assist device driveline infections caused by S. epidermidis. This pluripotential adherence capacity provides a potential pathway to infection with SdrF-positive commensal staphylococci first adhering to the external Dacron-coated driveline at the transcutaneous entry site, then spreading along the collagen-coated internal portion of the driveline to establish a localized infection. This capacity may also have relevance for other prosthetic device–related infections., Author Summary This study investigates the manner in which heart pumps become infected. Infections involving the driveline, the cord that connects the pump to its external power source, are a major complication of implantation of these devices. In this study, we examined why Staphylococcus epidermidis, a bacteria that is commonly found on the skin, is responsible for the majority of these infections. The ability of different surface molecules of S. epidermidis to attach to drivelines removed from patients undergoing transplantation was tested. SdrF, one of the S. epidermidis surface proteins studied, showed the highest adherence to the drivelines. This binding appeared to involve attachment of the B subunit of SdrF to collagen, a molecule that coats the driveline following implantation. SdrF also mediated attachment to the non-implanted Dacron material that is used to coat the drivelines. A mouse driveline infection model also demonstrated that SdrF was sufficient to initiate a driveline infection. Driveline infection can therefore be hypothesized to occur via: 1) skin colonization by S. epidermidis; 2) adherence of SdrF-positive S. epidermidis to the Dacron surface at the skin entry site; 3) migration of bacteria along the driveline; 4) adherence to the internal driveline via the collagen coating its surface; and 5) initiation of infection.

Objective Biomaterials and textured surfaces in early pulsatile left ventricular assist devices (HeartMate I; Thoratec Corporation, Pleasanton, Calif) may increase immunologic risk through allosensitization. We hypothesized that axial-flow devices without biologic membranes or textured surfaces (HeartMate II; Thoratec; and DeBakey; MicroMed Cardiovascular, Inc, Houston, Tex) would cause less allosensitization than devices with such membranes and surfaces. Methods HeartMate II and DeBakey (n = 24) and HeartMate I (n = 36) devices were implanted from 1999 to 2006 in patients with severe heart failure cohort-matched for age, etiology, and support duration. Serum samples reacting with more than 10% of the HLA reference panel were considered positive for anti-HLA antibodies. Endomyocardial biopsy samples were collected after transplant. Results There were no significant cohort differences in age, etiology, sex, blood transfusion, or support duration. Anti-HLA antibodies were not detected at implantation of either HeartMate II and DeBakey or HeartMate I devices; however, significant increases in anti-HLA antibodies were present within 1 and 3 months of support with HeartMate I but not HeartMate II and DeBakey devices. Overall, fewer patients with HeartMate II and DeBakey devices demonstrated positive anti-HLA antibodies during support (8% vs 28%, P = .02), and fewer episodes of acute rejection per patient were seen within the first 9 posttransplant months(0.31 vs 0.69, P = .052). Long-term posttransplant survival was not different between groups. Conclusion Hemodynamic support with HeartMate II and DeBakey devices produced less allosensitization than did HeartMate I devices. Device selection may improve clinical outcomes for high-risk patients.

RVsP). All patients were divided into two groups: Group 1 WITH PH, according to ISHLT criteria to indicate RHC and vasodilator challenge, and Group 2 WITHOUT PH. The ISHLT criteria are: PsAP 50mmHg (mTPG 15 and/or PVR 5 Wood units. The sensitivity of RVsP in the diagnosis of patients WITH PH was determined by a ROC curve. Results: A great correlation between sPAP and RVsP was obtained by a Pearson Correlation analysis (r 0,64, CI 95% 0,50 to 0,75, p 0,001). The analysis of ROC curve determined that the cutoff value of RVsP 45mmHg showed a sensitivity of 100% (specificity 37,2, CI 95%, p 0,0001) on the exclusion of Severe PH. Conclusions: The study determined and validated a non – invasive echo – Doppler parameter as a useful and efficacy tool during pulmonary hypertension evaluation in heart transplant candidates. The cutoff value RVsP 45mmHg exclude patients WITH pulmonary hypertension according to ISHLT data and allow us to proceed safety heart transplantation without invasive assessment of pulmonary hypertension degrees. These findings avoid risk rates secondary to invasive proceedings in about 33% of heart transplant candidates and allow them to be safety submitted to heart transplant.

Cognitive Impairment in Heart Failure: It Is More Than Just Depression J.R. Festa, P.A. Shapiro, D.M. Mancini, E.R. Lantz, M.C. Deng, Y. Naka, R.M. Lazar, Neurology, Columbia University Medical Center, College of Physicians and Surgeons, New York, NY; Psychiatry, Columbia University Medical Center, College of Physicians and Surgeons, New York, NY; Medicine Cardiology, Columbia University Medical Center, College of Physicians and Surgeons, New York, NY; Surgery, Columbia University Medical Center, College of Physicians and Surgeons, New York, NY; Neurosurgery, Columbia University Medical Center, College of Physicians and Surgeons, New York, NY

Use of a Murine Transcutaneous Ventricular Assist Device Driveline Model To Characterize S. epidermidis SDRF Binding M. von Bayern, C. Arrecubieta, I. Matsunaga, S. Oz, M. Cadieras, Y. Naka, M. Deng, F. Lowy, T. Asahi, Medicin, Columbia University, New York, NY; Surgery, Columbia University, New York, NY; Division of Infectious Diseases, Columbia University, New York, NY; Pathology, Columbia University, New York, NY

Internal mammary artery grafting in coronary artery bypass surgery has resulted in increased long-term patency and improved survival compared to venous bypass grafting. Angiography of the mammary arteries before bypass surgery is considered to be superfluous because they are rarely affected by atherosclerosis. 1 There are, however, no data on how often an internal mammary artery graft is intraoperatively rejected because of insufficient sluggish flow due to atherosclerosis. Early postoperative graft failure is said to be mainly related to technical errors. 2,3 To establish the frequency of atherosclerotic changes in the subclavian and internal mammary arteries among our patients, we performed semiselective angiography on both mammary arteries during cardiac catheterization in candidates for bypass surgery.

with a PCWP 15. The BNP was 150 pg/ml in only 42 of 124 (33.8%) measurements. In 29 patients with symptomatic heart failure and PCWP 15, the BNP was 150 on only 19 of 42 (45.2%) occasions. Therefore, a BNP level of 150 was found to have a sensitivity of only 45.2%, a specificity of 64.9%, a positive predictive value of 3.7%, and a negative predictive value of 2.4% for the detection of heart failure in heart transplant recipients. In addition, a BNP value 150 within 8 weeks of a clinically significant episode of rejection was noted in only 5 of 10 (50%) cases. Conclusions: BNP levels are not effective in determining clinically relevant heart failure following heart transplantation. In addition, it does not appear to predict rejection. The discrepancy between the utility of BNP in detecting heart failure in the transplant and nontransplant population may be due to denervated cardiac physiology but requires further investigation.

Background Long-term implantation of a left ventricular assist device (LVAD) may be a future alternative treatment for end-stage heart failure. The objective of the present study was to determine t...

The difference in the COP and EP between the borderline donor subgroup and all others was not statistically significant. Post-transplant survival was not significantly different from recipients of normal cardiac allograft (p 0.43). Likewise for the high-risk recipient group, the COP and EP were at 72 and 203 days respectively. Although post-op survival was shorter than the normal risk group, both groups achieve a survival benefit. Conclusion: Heart transplantation has survival benefit in both these risk groups of recipients and donors in our population reflecting our rigorous donor and recipient selection and management.

No data exist on the relation between angiography of the internal mammary artery and intraoperative findings during bypass surgery. We studied 47 consecutive patients and found no atherosclerotic changes. Intraoperatively, however, 4 left internal mammary arteries were judged unsuitable for grafting. No relation could be found to the diameter of the vessel as judged angiographically. Possible causes of unsuitability are discussed.