Marian Urban

How does successful bridging with ventricular assist device affect cardiac transplantation outcome

A best evidence topic in cardiac surgery was written according to a structured protocol. The issue was to determine the impact of bridge-to-transplant ventricular assist device support on survival after cardiac transplantation. Altogether 428 papers were found using the reported search, of which 12 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The treatment options for patients with advanced heart failure or those with deteriorating end-organ function on maximal medical therapy are limited to intravenous inotropes and mechanical assistance with intra-aortic balloon pump (IABP) or ventricular assist device (VAD). Studies exploring the effect of VADs on post-transplant mortality have yielded conflicting results. The Registry of the International Society for Heart and Lung Transplantation continues to identify mechanical support as a risk factor for decreased survival after transplantation. A limitation of this report is that the multivariable adjustment uses variables recorded not at the time of device implant but at the time of transplant. Some of the recipient characteristics thus may be altered by the device implant. Compared with the previous reports the latest data show improvement in post-transplant survival in the recent era. In addition, the excess risk appears to be limited to the early post-transplant period. Experienced centers consistently report outstanding post-transplant results with left ventricular assist device (LVAD) bridging. Of the 12 papers seven showed no difference in survival, and five showed a reduced survival. In the papers showing no difference, one year survival averaged from 85% in supported patients to 87% in non-supported patients. In papers reporting a difference in outcome, one year averaged survival was 74% in LVAD recipients compared to 90% in non-bridged patients. Decreased survival is associated with patients suffering from dilated cardiomyopathy, transplanted within two weeks of LVAD implantation and bridged to transplantation before 2003 as opposed to patients transplanted more recently. Based on the available evidence we conclude that in selected patients survival after heart transplantation in patients bridged with VAD is comparable to those who did not receive the device.

Total artificial heart support with two continuous-flow ventricular assist devices in a patient with an infiltrating cardiac sarcoma.

Primary cardiac sarcoma is normally fatal, but cardiac replacement may provide some hope for long-term survival. A 38 year-old man with cardiac sarcoma, involving the interventricular septum and posterior wall with intermittent mitral obstruction, underwent implantation of two HeartMate II ventricular assist devices for total artificial heart support. After cardiectomy, the HeartMate sewing rings were sewn to the right neoatrium and the left atrial remnants. After the outflow grafts were sewn end to end to the pulmonary artery and aorta, the two drivelines were externalized through the abdominal wall, and perfusion started. The postoperative course was complicated by respiratory and renal dysfunction, which resolved. After 6 months of support, the patient has normal organ function and is ambulatory. Follow-up oncologic evaluation of positron emission tomography-computed tomography scan is negative.

Alloimmunosensitization in left ventricular assist device recipients and impact on posttransplantation outcome.

Left ventricular assist devices (LVADs) have become an established surgical therapy for patients with end-stage heart failure who require hemodynamic support as a bridge-to-transplant or destination therapy. However, the anatomic and physiologic consequences of long-term LVAD support have yet to be fully clarified. Despite the clinical success of these devices, it has been reported that many patients bridged to transplantation with mechanical support develop circulating antibodies with potential donor reactivity. Transplanting against existing or historic donor-specific antibodies is associated with increased risk of antibody-mediated rejection, graft dysfunction, and decreased survival. Safe transplantation of allosensitized patients is dependent on using prospective crossmatching and antibody titer reduction techniques (desensitization). Strict protocols requiring a negative prospective crossmatch before transplantation result in a decreased donor pool and a longer duration of support in sensitized LVAD recipients with increased inherent morbidity such as infections and thromboembolic complications. The aim of this review is to present the current state of knowledge of possible immunologic mechanisms involved in alloimmunization of LVAD recipients, outline new methods of antibody detection, compare various desensitization strategies, and present an overview of clinical data assessing the impact of sensitization on posttransplantation outcome.

The impact of angiotensin II type 1 receptor antibodies on post-heart transplantation outcome in Heart Mate II bridged recipients

OBJECTIVES Antibodies targeting angiotensin II type 1 receptor (AT1R) have been associated with malignant hypertension, autoimmune diseases and acute rejection and graft loss in solid organ transplantation. The aim of our study was to assess the impact of anti-AT1R antibodies on survival and incidence of acute cellular rejection (ACR) and pathology antibody-mediated rejection (pAMR) in a population of heart transplant recipients who were bridged to transplantation with a durable mechanical assist device Heart Mate II. METHODS Sera of 69 consecutive heart transplant recipients transplanted between October 2008 and August 2014 were tested for the presence of angiotensin II type 1 receptor antibodies before Heart Mate II device implantation and at the time of transplantation. Overall survival and post-transplant rejection-free survival were compared between antibody-negative and antibody-positive recipients using Kaplan-Meier and log-rank tests. RESULTS Anti-AT1R antibodies were present in 8 patients (11.6%) before Heart Mate II implantation. During the left ventricular assist device (LVAD) bridging, 44 patients (63.8%) who were initially anti-AT1R antibody-negative became positive, leaving 17 (24.6%) anti-AT1R antibody-negative patients at the time of transplantation for all comparisons. One- and 5-year survival was 88 ± 8 and 76 ± 10% for anti-AT1R antibody-negative and 87 ± 5 and 81 ± 7% for anti-AT1R antibody-positive patients, respectively (P = 0.582). Freedom from ACR at 1 year was 68 ± 12% for anti-AT1R-negative and 75 ± 6% for anti-AT1R-positive recipients (P = 0.218). None of the anti-AT1R-negative patients developed AMR 1 year post-transplantation, whereas freedom from pAMR in anti-AT1R-positive recipients was 98 ± 2% (P = 0.198). CONCLUSIONS Our data showed no difference in the overall post-heart transplant survival and freedom from acute cellular and antibody-mediated rejection between anti-AT1R-negative and anti-AT1R-positive recipients. Further research is needed to assess the role of anti-AT1R antibodies in the risk stratification of LVAD-bridged recipients on the post-heart transplantation outcomes.

Novel insights into pretransplant allosensitization in heart transplant recipients in the contemporary era of immunosuppression and rejection surveillance

Solid‐phase assays (SPA) have facilitated detection and definition of antibodies to human leukocyte antigens (HLA) and major histocompatibility complex class I chain‐related antigen A (MICA). However, clinical consequences of pretransplant SPA results in heart transplantation have been studied insufficiently in the current era of immunosuppression and rejection surveillance. Pretransplant sera, panel‐reactive antibodies (PRA), pretransplant crossmatch, and clinical data were retrospectively analyzed in 264 adult heart transplant recipients. The specificity of HLA and MICA antibodies and C1q‐binding activity of donor‐specific antibodies (DSA) were defined using SPA. Pretransplant HLA antibodies were detected in 57 (22%) individuals, in 28 individuals (11%); these antibodies were DSA after transplant. Preformed DSA and elevated peak PRA were independent predictors of pathologic AMR, which occurred in 19 individuals (7%). The increasing number of DSA and the cumulative mean fluorescence intensity of DSA were associated with AMR. C1q‐binding assay was a suboptimal predictor of AMR in our cohort. Pretransplant allosensitization and MICA antibodies were related neither to impaired graft survival nor to other adverse clinical events during a median follow‐up of 39 months. Identification of preformed DSA by SPA, in addition to PRA monitoring, may predict AMR in the contemporary era of heart transplantation.

Aortic and Mitral Valve Replacement Due to Extensive Inflammatory Immunoglobulin G4-Related Pseudotumor.

A 64-year-old woman with extensive tumorous infiltration of the mitral and aortic valves underwent partial resection of a tumor of the left ventricular outflow tract and replacement of both affected valves. Histology revealed an inflammatory pseudotumor with a significant number of immunoglobulin-G4-positive plasma cells. The histologic and clinical findings suggested immunoglobulin-G4-related disease of the heart.

Novel treatment of an infiltrating cardiac fibrosarcoma.

A 38-year-old man was diagnosed with primary cardiac sarcoma involving the central cardiac structures. Echocardiography revealed that a pendular portion of the tumor intermittently obstructed the mitral orifice. Magnetic resonance imaging verified infiltration into the interventricular septum and the posterior wall of the left ventricle. A biopsy report showed moderate- to high-grade fibrosarcoma, and a positron emission tomographic–computed tomographic (PET-CT) scan ruled out metastasis. The patient consented to cardiectomy and to the placement of 2 HeartMate® II (Thoratec Corporation; Pleasanton, Calif ) continuous-flow ventricular assist devices (VADs). After the heart was excised (Fig. 1), only the posterior walls of both atria remained. A right neoatrium was created with a 38-mm reinforced graft that was attached to a sewing ring, as reported previously.1 Another sewing ring was attached to the left atrial tissue; both VAD inflow conduits were secured within the sewing rings (Fig. 2). Left and right outflow grafts were anastomosed end-to-end to the aorta and the pulmonary artery, respectively. In this patient, there was no dilated pericardial cavity because of the specific reason for his surgery. We were aware that retaining appropriate pericardial bulk was crucial to the patients eligibility for future heart transplantation. To meet this goal, we did not use a technique described in 20122; instead, we positioned the pumps to accommodate the whole left part of the remaining pericardial cavity and used longer outflow grafts (in bend reliefs) to fill the whole pericardial cavity (Fig. 3). Postoperative computed tomography showed the configuration of the artificial heart (Figs. 4 and ​and55). Fig. 1 Perioperative photograph shows the solid extramural part of the sarcoma (double arrow) and the pendular infiltrating part within the mitral orifice (single arrow). Fig. 2 Intraoperative photograph shows preparation of the inflow attachments after cardiectomy. Fig. 3 Intraoperative photograph shows final positioning of the total artificial heart. Fig. 4 Postoperative 3-dimensional computed tomographic reconstruction image shows positioning of the pumps and inflow cannulas. Fig. 5 Postoperative 3-dimensional computed tomographic reconstruction shows end-to-end anastomosis of the outflow grafts.

What is the optimal mode of mechanical support in transplanted patients with acute graft failure

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: is extracorporeal membrane oxygenation (ECMO) superior to dedicated ventricular assist device (VAD) in patients with acutely failing allograft following transplantation. Altogether, 162 papers were found using the reported search, of which 8 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Two studies provide data only for ECMO-treated patients, in three, the authors describe their experiences with Levitronix CentriMag and three studies directly compare the outcomes of ECMO and VAD support. The survival ranges from 40 to 74% in patients rescued with ECMO compared with 33-60% in patients supported with dedicated VAD. We conclude that there is insufficient evidence to prefer ECMO over VAD and the optimal modality of mechanical circulatory support (MCS) following heart transplantation should be determined by the surgeon and institutional experience and dependent on the extent and severity of myocardial dysfunction and the presence or absence of associated respiratory insufficiency.

In patients with concomitant aortic and mitral valve disease is aortic valve replacement with mitral valve repair superior to double valve replacement

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was: in patients with concomitant aortic and mitral valve disease is aortic valve replacement with mitral valve plasty (MVP) superior to double valve replacement (DVR) in terms of improved long-term survival? Altogether 156 papers were found using the reported search, of which seven represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. Out of seven papers, that simultaneously compare these two treatment modalities, three favor MVP combined with aortic valve replacement (AVR) over DVR, two papers advocate the opposite and two failed to find any significant difference in long-term survival, freedom from reoperation and thromboembolic and bleeding complications between these two surgical options. All data presented derive from level 2b evidence. Critical appraisal of these studies is constricted by the large heterogeneity of the patients, diversity in treatment protocols and inherent selection bias. We conclude that currently the available evidence is insufficient to prove that AVR with MVP is superior to DVR in patients with double valve disease.

Intracardiac ectopic thyroid (struma cordis).

A 67‐year‐old male with a history of gastrointestinal malignancy was found to have a tumor in the right ventricular outflow tract. The tumor was surgically removed, and the histological diagnosis was thyroid struma. We review the literature on this rare cardiac tumor. doi: 10.1111/jocs.12245 (J Card Surg 2014;29:155–158)