Heidi Reich

Cardiospheres reverse adverse remodeling in chronic rat myocardial infarction: roles of soluble endoglin and Tgf-β signaling

Self-assembling heart-derived stem cell clusters named cardiospheres (CSps) improve function and attenuate remodeling in rodent models of acute myocardial infarction. The effects of CSps in chronically remodeled myocardium post-MI, and the underlying mechanisms, remain unknown. One month after permanent coronary ligation, rats were randomly assigned to injection of vehicle (controls) or CSps in the peri-infarct area. One month post-injection, CSps increased left ventricular function, reduced scar mass and collagen density, and enhanced vascularity within the infarct zone compared to controls. Immunoblots revealed Tgfβ-1/smad cascade downregulation and an increase in soluble endoglin post-CSp injection. Six months post-transplantation, left ventricular function further improved and cardiomyocyte hypertrophy was attenuated in the CSp-treated group. In vitro, co-culture of CSps with fibroblasts recapitulated the suppression of the Tgf-β1/smad pathway changes, responses which were blunted by neutralizing antibody against endoglin. Thus, cardiosphere transplantation enhances angiogenesis and reduces fibrosis in chronically infarcted myocardium, leading to partial reversal of cardiac dysfunction. The underlying mechanism involves inhibition of Tgf-β1/smad signaling by CSp-secreted soluble endoglin.

Intracoronary Delivery of Self-Assembling Heart-Derived Microtissues (Cardiospheres) for Prevention of Adverse Remodeling in a Pig Model of Convalescent Myocardial Infarction

Background—Preclinical studies in rodents and pigs indicate that the self-assembling microtissues known as cardiospheres may be more effective than dispersed cardiosphere-derived cells. However, the more desirable intracoronary route has been assumed to be unsafe for cardiosphere delivery: Cardiospheres are large (30–150 &mgr;m), raising concerns about likely microembolization. We questioned these negative assumptions by evaluating the safety and efficacy of optimized intracoronary delivery of cardiospheres in a porcine model of convalescent myocardial infarction. Methods and Results—First, we standardized the size of cardiospheres by modifying culture conditions. Then, dosage was determined by infusing escalating doses of cardiospheres in the left anterior descending artery of naive pigs, looking for acute adverse effects. Finally, in a randomized efficacy study, 14 minipigs received allogeneic cardiospheres (1.3×106) or vehicle 1 month after myocardial infarction. Animals underwent magnetic resonance imaging before infusion and 1 month later to assess left ventricular ejection fraction, scar mass, and viable mass. In the dosing study, we did not observe any evidence of microembolization after cardiosphere infusion. In the post-myocardial infarction study, cardiospheres preserved LV function, reduced scar mass and increased viable mass, whereas placebo did not. Moreover, cardiosphere decreased collagen content, and increased vessel densities and myocardial perfusion. Importantly, intracoronary cardiospheres decreased left ventricular end-diastolic pressure and increased cardiac output. Conclusions—Intracoronary delivery of cardiospheres is safe. Intracoronary cardiospheres are also remarkably effective in decreasing scar, halting adverse remodeling, increasing myocardial perfusion, and improving hemodynamic status after myocardial infarction in pigs. Thus, cardiospheres may be viable therapeutic candidates for intracoronary infusion in selected myocardial disorders.

Combined Heart and Liver Transplantation: The Cedars-Sinai Experience

PURPOSE Combined heart-liver transplantation is an increasingly accepted treatment for select patients with heart and liver disease. Despite growing optimism, heart-liver transplantation remains an infrequent operation. We report our institutional experience with heart-liver transplantation. METHODS All combined heart-liver transplantations at Cedars-Sinai Medical Center from 1998-2014 were analyzed. Primary outcomes were patient and graft survival and secondary outcomes included rejection, infection, reoperation, length of stay, and readmission. RESULTS There were 7 heart-liver transplants: 6 simultaneous (single donor) and 1 staged (2 donors). Median follow-up was 22.1 (IQR 13.2-48.4) months. Mean recipient age was 50.8 ± 19.5 years. Heart failure etiologies included familial amyloidosis, congenital heart disease, hypertrophic cardiomyopathy, systemic lupus erythematosus, and dilated cardiomyopathy. Preoperative left ventricular ejection fraction averaged 32.3 ± 12.9%. Five (71.4%) patients required preoperative inotropic support; 1 required mechanical circulatory support. The most common indications for liver transplant were amyloidosis and cardiac cirrhosis. Median Model for End-stage Liver Disease score was 10.0 (9.3-13.8). Six-month and 1-year actuarial survivals were 100% and 83.3%, with mean survival exceeding 4 years. No patient experienced cardiac allograft rejection, 1 experienced transient liver allograft rejection, and 1 developed progressive liver dysfunction resulting in death. Five developed postoperative infections and 3 (42.9%) required reoperation. Median ICU and hospital stays were 7.0 (7.0-11.5) and 17.0 (13.8-40.5) days. There were 4 (57.1%) readmissions. CONCLUSIONS For carefully selected patients with coexisting heart and liver disease, combined heart and liver transplantation offers acceptable patient and graft survival.

Adult Heart Transplantation Following Ventricular Assist Device Implantation: Early and Late Outcomes

PURPOSE The impact of prior implantation of a ventricular assist device (VAD) on short- and long-term postoperative outcomes of adult heart transplantation (HTx) was investigated. METHODS Of the 359 adults with prior cardiac surgery who underwent HTx from December 1988 to June 2012 at our institution, 90 had prior VAD and 269 had other (non-VAD) prior cardiac surgery. RESULTS The VAD group had a lower 60-day survival when compared with the Non-VAD group (91.1% ± 3.0% vs 96.6% ± 1.1%; P = .03). However, the VAD and Non-VAD groups had similar survivals at 1 year (87.4% ± 3.6% vs 90.5% ± 1.8%; P = .33), 2 years (83.2% ± 4.2% vs 88.1% ± 2.0%; P = .21), 5 years (75.7% ± 5.6% vs 74.6% ± 2.9%; P = .63), 10 years (38.5% ± 10.8% vs 47.6% ± 3.9%; P = .33), and 12 years (28.9% ± 11.6% vs 39.0% ± 4.0%; P = .36). The VAD group had longer pump time and more intraoperative blood use when compared with the Non-VAD group (P < .0001 for both). Postoperatively, VAD patients had higher frequencies of >48-hour ventilation and in-hospital infections (P = .0007 and .002, respectively). In addition, more VAD patients had sternal wound infections when compared with Non-VAD patients (8/90 [8.9%] vs 5/269 [1.9%]; P = .005). Both groups had similar lengths of intensive care unit (ICU) and hospital stays and no differences in the frequencies of reoperation for chest bleeding, dialysis, and postdischarge infections (P = .19, .70, .34, .67, and .21, respectively). Postoperative creatinine levels at peak and at discharge did not differ between the 2 groups (P = .51 and P = .098, respectively). In a Cox model, only preoperative creatinine ≥1.5 mg/dL (P = .006) and intraoperative pump time ≥210 minutes (P = .022) were individually considered as significant predictors of mortality within 12 years post-HTx. Adjusting for both, pre-HTx VAD implantation was not a predictor of mortality within 12 years post-HTx (hazard ratio [HR], 1.23; 95% confidence interval [CI], 0.77-1.97; P = .38). However, pre-HTx VAD implantation was a risk factor for 60-day mortality (HR, 2.86; 95% CI, 1.07-7.62; P = .036) along with preoperative creatinine level ≥2 mg/dL (P = .0006). CONCLUSIONS HTx patients with prior VAD had lower 60-day survival, higher intraoperative blood use, and greater frequency of postoperative in-hospital infections when compared with HTx patients with prior Non-VAD cardiac surgery. VAD implantation prior to HTx did not have an additional negative impact on long-term morbidity and survival following HTx. Long-term (1-, 2-, 5-, 10-, and 12-year) survival did not differ significantly in HTx patients with prior VAD or non-VAD cardiac surgery.

Intermediate Outcomes with Ex-Vivo Allograft Perfusion for Heart Transplantation

BACKGROUND The Organ Care System, an ex-vivo heart perfusion platform, represents an alternative to the current standard of cold organ storage that sustains the donor heart in a near-physiologic state. It is unknown whether using the Organ Care System influences 2-year outcomes after heart transplantation. We reviewed our institutional experience to compare 2-year outcomes for patients randomized to the Organ Care System or standard cold storage. METHODS Between 2011 and 2013, heart transplant candidates from a single tertiary-care medical center enrolled within the PROCEED II trial were randomized to either standard cold storage or the Organ Care System. Outcomes assessed included 2-year survival, freedom from cardiac allograft vasculopathy (CAV), non-fatal major cardiac events (NF-MACE), biopsy-proven cellular rejection (CMR) and biopsy-proven antibody-mediated rejection (AMR). RESULTS Thirty-eight patients were randomized to the Organ Care System (n = 19) or cold storage group (n = 19). There was no significant difference in 2-year patient survival (Organ Care System: 72.2%; cold storage: 81.6%; p = 0.38). Similarly, there were no differences in freedom from CAV, NF-MACE, CMR or AMR. The Organ Care System group had significantly longer total ischemia time (361 ± 96 minutes vs 207 ± 50 minutes; p < 0.001) and shorter cold ischemia time (134 ± 45 minutes vs 207 ± 50 minutes; p < 0.001) compared with the cold storage group. CONCLUSION The Organ Care System did not appear to be associated with significant differences in intermediate results compared with conventional strategies. These results suggest that this ex-vivo allograft perfusion system is a promising and valid platform for donor heart transportation.

Repeated transplantation of allogeneic cardiosphere-derived cells boosts therapeutic benefits without immune sensitization in a rat model of myocardial infarction

BACKGROUND A single dose of allogeneic cardiosphere-derived cells (CDCs) improves cardiac function and reduces scarring, and increases viable myocardium in the infarcted rat and pig heart without eliciting a detrimental immune response. Clinical trials using single doses of allogeneic human CDCs are underway. It is unknown whether repeat dosing confers additional benefit or if it elicits an immune response. METHODS Wistar-Kyoto rats underwent coronary artery ligation and intramyocardial injection of CDCs, with a second thoracotomy and repeat CDC injection 3 weeks later. Treatment permutations included 2 doses of allogeneic Brown-Norway CDCs (n = 24), syngeneic Wistar-Kyoto CDCs (n = 24), xenogeneic human CDCs (n = 24) or saline (n = 8). Cardiac function was assessed by transthoracic echocardiography, infarct size and inflammatory infiltration by histology, and cellular and humoral immune responses by lymphocyte proliferation and alloantibody assays. RESULTS Repeat dosing of allogeneic and syngeneic CDCs improved ejection fraction by 5.2% (95% CI 2.1 to 8.3) and 6.8% (95% CI 3.8 to 9.8) after the first dose, and by 3.4% (95% CI 0.1% to 6.8%) and 6.4% (95% CI 4.2% to 8.6%) after the second dose. Infarct size was equally reduced with repeat dosing of syngeneic and allogeneic CDCs relative to xenogeneic and control treatments (p < 0.0001). Significant rejection-like infiltrates were present only in the xenogeneic group; likewise, lymphocyte proliferation and antibody assays were positive in the xenogeneic and negative in syngeneic and allogeneic groups. CONCLUSIONS Repeat dosing of allogeneic CDCs in immunocompetent rats is safe and effective, consistent with the known immunomodulatory and anti-inflammatory properties of CDCs. These findings motivate clinical testing of repeatedly dosed CDCs for chronic heart disease.

Prior sternotomy increases the mortality and morbidity of adult heart transplantation.

BACKGROUND This study investigated the effect of prior sternotomy (PS) on the postoperative mortality and morbidity after orthotopic heart transplantation (HTx). METHODS Of 704 adults who underwent HTx from December 1988 to June 2012 at a single institution, 345 had no PS (NPS group) and 359 had ≥ 1 PS (PS group). Survival, intraoperative use of blood products, intensive care unit (ICU) and hospital stays, frequency of reoperation for bleeding, dialysis, and >48-hour ventilation were examined. RESULTS The NPS and PS groups had similar 60-day survival rates (97.1 ± 0.9% vs 95.3 ± 1.1%; P = .20). However, the 1-year survival was higher in the NPS group (94.7 ± 1.2% vs 89.7 ± 1.6%; hazard ratio [HR], 1.98; 95% CI, 1.12-3.49; P = .016). The PS group had longer pump time and more intraoperative blood use (P < .0001 for both). Postoperatively, the PS group had longer ICU and hospital stays, and higher frequencies of reoperation for bleeding and >48-hour ventilation (P < .05 for all comparisons). Patients with 1 PS (1PS group) had a higher 60-day survival rate than those with ≥ 2 PS (2+PS group; 96.7 ± 1.1% vs 91.1 ± 3.0%; HR, 2.70; 95% CI, 1.04-7.01; P = .033). The 2+PS group had longer pump time and higher frequency of postoperative dialysis (P < .05 for both). Patients with prior VAD had lower 60-day (91.1 ± 3.0% vs 97.1 ± 0.9%; P = .010) and 1-year (87.4 ± 3.6% vs 94.7 ± 1.2%; P = .012) survival rates than NPS group patients. Patients with prior CABG had a lower 1-year survival than NPS group patients (89.0 ± 2.3% vs 94.7 ± 1.2%; P = .018). CONCLUSION The PS group had lower 1-year survival and higher intraoperative blood use, postoperative length of ICU and hospital stays, and frequency of reoperation for bleeding than the NPS group. Prior sternotomy increases morbidity and mortality after HTx.

Small bowel carcinoid: Location isn’t everything!

AIM To investigate the prognostic significance of the primary site of disease for small bowel carcinoid (SBC) using a population-based analysis. METHODS The Surveillance, Epidemiology and End Results (SEER) database was queried for histologically confirmed SBC between the years 1988 and 2009. Overall survival (OS) and disease-specific survival (DSS) were analyzed using the Kaplan-Meier method and compared using Log rank testing. Log rank and multivariate Cox regression analyses were used to identify predictors of survival using age, year of diagnosis, race, gender, tumor histology/size/location, tumor-node-metastasis stage, number of lymph nodes (LNs) examined and percent of LNs with metastases. RESULTS Of the 3763 patients, 51.2% were male with a mean age of 62.13 years. Median follow-up was 50 mo. The 10-year OS and DSS for duodenal primaries were significantly better when compared to jejunal and ileal primaries (P = 0.02 and < 0.0001, respectively). On multivariate Cox regression analysis, after adjusting for multiple factors, primary site location was not a significant predictor of survival (P = 0.752 for OS and P = 0.966 DSS) while age, number of primaries, number of LNs examined, T-stage and M-stage were independent predictors of survival. CONCLUSION This 21-year, population-based study of SBC challenges the concept that location of the primary lesion alone is a significant predictor of survival.

Hemodynamic Consequences of Laparoscopy for Patients on Mechanical Circulatory Support

Background: Technologic advances and superior survival with mechanical circulatory support (MCS) led to an expanding population that develops intra-abdominal conditions requiring intervention. Whether laparoscopy can be performed without detrimental effects on hemodynamics and device function is not well-described. Methods: Effects of laparoscopy performed on MCS were retrospectively assessed. Intraoperative hemodynamics and device function were compared to the same time interval 24h prior to surgery using intrapatient paired t-tests. Outcomes included survival, transfusion, thromboembolic events, and infection. Results: Twelve patients with ventricular assist devices or total artificial hearts underwent laparoscopy from 2012-2014. Median follow-up was 116 days. Operations included cholecystectomy, diagnostic laparoscopy, gastrojejunostomy, and gastrostomy. There were no differences between preoperative and intraoperative mean arterial pressure, heart rate, or inotrope or vasopressor requirements (p>0.05). Device fill volume, flow, rate, and power were unchanged (p>0.05), while pulsatility index decreased by 0.2, 95% CI [0.03, 0.36], with laparoscopy (p=0.03). All intraoperative fluctuations in hemodynamics and device function improved with reduction of pneumoperitoneum, adjusting device speed, or pharmacologic support. There were no operative mortalities. 30-day survival and survival to discharge were 75% and 50%. Despite antiplatelet therapy and preoperative INR of 2.2 ± 0.9, there were no re-operations for bleeding and 50% did not require transfusion. Two patients with recent cardiac surgery had thromboembolic events: 1 stroke, 1 device thrombus. None had postoperative bacteremia or drive-line infection. Conclusions: Laparoscopy can be performed on mechanical circulatory support with low morbidity and mortality and minimal perturbations in hemodynamics and device function.

Comparative analysis of von Willebrand factor profiles after implantation of left ventricular assist device and total artificial heart

Essentials Bleeding is a major source of morbidity during mechanical circulatory support. von Willebrand factor (VWF) multimer loss may contribute to bleeding. Different patterns of VWF multimer loss were seen with the two device types. This is the first report of total artificial heart associated VWF multimer loss.