M. Awad

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.

Heart Transplantation With and Without Prior Sternotomy: Analysis of the United Network for Organ Sharing Database

INTRODUCTION Patients with history of prior sternotomy may have poorer outcomes after heart transplantation. Quantitation of risk from prior sternotomy has not been well established. The United Network for Organ Sharing (UNOS) database was analyzed to assess early and late survival and predictors of outcome in adult heart transplant recipients with and without prior sternotomy. METHODS Of 11,266 adults with first heart-only transplantation from 1997 to 2011, recipients were divided into 2 groups: those without prior sternotomy (first sternotomy group; n = 6006 or 53.3%) and those with at least 1 prior sternotomy (redo sternotomy group; n = 5260 or 46.7%). A multivariable Cox model was used to identify predictors of mortality. RESULTS Survival was lower in the redo group at 60 days (92.6% vs 95.9%; hazard ratio [HR] 1.83, 95% confidence interval [CI]: 1.56-2.15; P < .001). Conditional 5-year survival in 60-day survivors was similar in the 2 groups (HR = 1.01, 95% CI 0.90-1.12, P = .90). During the first 60 days post-transplant, the redo group had more cardiac reoperations (12.3% vs 8.8%, P = .0008), a higher frequency of dialysis (8.9% vs 5.2%, P < .0001), a greater percentage of drug-treated infections (23.2% vs 19%, P = .003), and a higher percentage of strokes (2.5% vs 1.4%, P = .0001). A multivariable Cox proportional hazards model identified prior sternotomy as a significant independent predictor of mortality, in addition to age, female gender, congenital cardiomyopathy, need for ventilation, mechanical circulatory support, dialysis prior to transplant, pretransplant serum bilirubin (≥ 3 mg/dL), and preoperative serum creatinine (≥ 2 mg/dL). CONCLUSIONS Prior sternotomy is associated with an excess 3.3% mortality and higher morbidity within the first 60 days after heart transplantation, as measured by frequency of dialysis, drug-treated infections, and strokes. Conditional 5-year survival after 60 days is unaffected by prior sternotomy. These findings should be taken into account for risk assessment of patients undergoing heart transplantation.

Early Denervation and Later Reinnervation of the Heart Following Cardiac Transplantation: A Review

Heart transplantation (HTx) surgically interrupts the parasympathetic vagal neurons and the intrinsic postganglionic sympathetic nerve fibers traveling from the stellate ganglia to the myocardium, causing axonal Wallerian degeneration and thus extrinsic cardiac denervation.[1][1], [2][2], [3][3], [4

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.

Prevalence of hypertension in the Gambia and Sierra Leone, western Africa : a cross-sectional study : cardiovascular topic

Summary Background Hypertension (HTN) is one of the causes of cardiovascular disease (CVD) in Africa, and may be associated with lower socio-economic status (SES). The prevalence of HTN is not well established in the Gambia or in Sierra Leone. Methods A cross-sectional, population-based study of adults was conducted in the Gambia in 2000 and in Sierra Leone from 2001 to 2003 and in 2009. The study was conducted as part of the annual visit to countries in western Africa sponsored by a medical delegation from California. People from the Gambia and Sierra Leone were examined by the medical delegation and blood pressures were measured. Results A total of 2 615 adults were examined: 1 400 females and 1 215 males. The mean systolic blood pressure (SBP) of the females was 134.3 ± 29.7 mmHg, mean diastolic blood pressure (DBP) was 84.5 ± 17.5 mmHg, and 46.2% were hypertensive. The mean SBP of the males was 132.8 ± 28.5 mmHg, mean DBP was 82.8 ± 16.2 mmHg, and 43.2% were hypertensive. Overall prevalence of HTN in the subjects was 44.8%. Mean SBP, mean DBP and HTN prevalence increased with age decade, both in males and females. In addition, after age adjustment (known age), females had higher mean SBP (p = 0.042), mean DBP (p = 0.001) and rate of occurrence of HTN (p = 0.016) when compared with males. Conclusions Prevalence rates of HTN in the Gambia and Sierra Leone were higher than 40% in males and females, and may be a major contributor to CVD in both countries. Due to the association of HTN with low SES, improvements in educational, public health, economic, non-governmental and governmental efforts in the Gambia and Sierra Leone may lead to a lower prevalence of HTN. The cause of the higher prevalence in women may be due to post-menopausal hormonal changes.

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.

Prophylaxis of Cytomegalovirus Disease in Mismatched Patients after Heart Transplantation Using Combined Antiviral and Immunoglobulin Therapy

BACKGROUND Cytomegalovirus (CMV) is a common cause of infection and morbidity after heart transplantation. Seronegative recipients (R-) of seropositive donor hearts (D+) are at high risk for CMV disease. We compared three different CMV prophylaxis regimens using combined antiviral and immunoglobulin therapy. METHODS In 99 patients who survived more than 30 days after heart transplant, all received induction with antilymphocytic therapy and triple-drug therapy. In group A, D+R- patients received one dose of intravenous immunoglobulin (IVIG) followed by one dose of CMV-specific immunoglobulin (CMV-IVIG), and intravenous ganciclovir (GCV) for 4 weeks followed by 11 months of oral acyclovir (ACV). In group B, D+R- patients received one dose IVIG followed by five doses of CMV-IVIG and intravenous GCV for 14 weeks followed by 9 months of oral ACV. In group C, D+R- patients were treated with the same regimen as for group B, except oral ACV was replaced with oral GCV. RESULTS The actuarial freedom from CMV disease for D+R- patients at 1 month, 1 year, and 2 years after transplantation in group A was 100%, 25% ± 15%, and 25% ± 15%, respectively; group B was 100%, 67% ± 27%, and 67% ± 27%; group C was 100%, 83% ± 15%, and 83% ± 15% (P < .01, groups B and C vs group A). By comparison, the actuarial freedom from CMV disease for seropositive recipients (D-R+ or D+R+) at 1 month, 1 year, and 2 years in group A was 100%, 87% ± 7%, and 82% ± 8%, respectively; group B was 100%, 88% ± 8%, and 75% ± 11%; group C was 100%, 72% ± 9%, and 72% ± 9% (P = NS among groups). Rejection rates did not differ among the three groups. CONCLUSIONS A longer course of intravenous GCV with multiple doses of CMV-IVIG was a more effective prophylaxis regimen against CMV disease for the high-risk group of seronegative recipients of seropositive donor hearts.

Prevalence of Warfarin Genotype Polymorphisms in Patients with Mechanical Circulatory Support.

Polymorphisms for VKORC1 and CYP2C9 are associated with increased warfarin sensitivity. The prevalence of these polymorphisms in patients with mechanical circulatory support (MCS) is unknown. Polymorphisms for VKORC1 and CYP2C9 were determined in 65 patients undergoing MCS surgery. Postoperative warfarin dose, international normalized ratio (INR), and bleeding events were measured until discharge, 6 months, or composite end point (in-hospital MCS recovery, heart transplant, or death). A total of 67.7% (44/65) had at least one polymorphism: VKORC1 (44.6%), CYP2C9*2 (7.7%), CYP2C9*3 (4.6%), CYP2C9*2 and VKORC1 (3.1%), or CYP2C9*3 and VKORC1 (7.7%). At discharge or before composite end point, patients with any polymorphism received a lower mean warfarin dosage than patients having no polymorphism (3.21 ± 1.47 vs. 5.57 ± 3.72 mg, p = 0.015) and achieved a similar mean INR (2.20 ± 0.67 vs. 2.19 ± 0.69, p = 0.96). There was no significant difference in bleeding rates within 6 months or before composite end point (6.13 vs. 8.02 events/patient-year, p = 0.13). One or more polymorphisms for VKORC1 or CYP2C9 (associated with warfarin sensitivity) were found in 67.7% of MCS patients. By using a warfarin genotype-guided approach, MCS patients with polymorphisms received a lower warfarin dosage to achieve a similar INR, with similar bleeding rates, in comparison with no polymorphisms. A warfarin genotype-guided approach avoided excessive anticoagulation and its attendant bleeding risks.

Exercise Performance Comparison of Bicaval and Biatrial Orthotopic Heart Transplant Recipients

BACKGROUND The standard biatrial technique for orthotopic heart transplantation uses a large atrial anastomosis to connect the donor and recipient atria. A modified technique involves bicaval and pulmonary venous anastomoses and is believed to preserve the anatomic configuration and physiological function of the atria. Bicaval heart transplantation reduces postoperative valvular regurgitation and is associated with a lower incidence of pacemaker insertion. OBJECTIVE The aim of this study was to compare postoperative functional capacity and exercise performance in patients with bicaval and biatrial orthotopic heart transplantation. METHODS Patients were selected for the study if they did not have any of the following: obstructive coronary artery disease (>50% stenosis), severe mitral or tricuspid regurgitation, signs of rejection (grade≥1B-1R) on endomyocardial biopsy during the prior year, respiratory impairment, a permanent pacemaker, orthopedic or muscular impediments, or lived more than 150 miles from the medical center. A total of 27 patients qualified. In 15 patients who received a biatrial heart transplant and 12 patients with a bicaval heart transplant, a stationary bicycle exercise test was performed. Ventilatory gas exchange and maximum oxygen consumption measurements were measured. RESULTS Recipient and donor characteristics, including body surface area, donor/recipient weight mismatch, immunosuppressive regimen, and self-reported weekly exercise activity, did not differ between the biatrial and bicaval groups (P=not significant [NS]). At peak exercise, similar heart rate, workload, oxygen consumption, carbon dioxide production, ventilation, functional capacity, and exercise duration were found between the 2 groups (P=NS). Patients in the biatrial group were studied later than patients in the bicaval group (6.54±0.71 vs 4.68±0.28 years; P<.001). CONCLUSION There were no significant differences in the exercise capacity between patients with biatrial versus bicaval techniques for orthotopic heart transplantation. Factors other than the atrial connection (such as cardiac denervation, immunosuppressive drug effect, or physical deconditioning) may be more important determinants of subnormal exercise capacity after heart transplantation. Nevertheless, the reduction in morbidity and postoperative complications and the simplicity in the bicaval technique suggest that bicaval heart transplantation offers advantages when compared with the standard biatrial technique.

Endomyocardial Biopsy Technique for Orthotopic Heart Transplantation and Cardiac Stem-Cell Harvesting

INTRODUCTION Orthotopic heart transplantation (OHT) is performed using the bicaval and pulmonary venous anastomoses or the standard (biatrial) anastomoses. The special considerations of endomyocardial biopsy after OHT using the bicaval technique, and after myocardial infarction for harvesting of cardiac stem cells, have not been described. METHODS When approached via the right or left internal jugular vein, important technical considerations were ultrasound guidance for vascular access; a soft, 80-cm, 0.035-inch, J-tipped guidewire; a long (23-cm), 7-Fr sheath; and a flexible 7-Fr, 50-cm bioptome. These technical aspects were helpful to avoid disruption of the superior vena cava suture line, avoid entry into the right atrial appendage or coronary sinus, avoid right ventricular free wall perforation, and provide ready access to the right ventricular septal wall. We used the same principles and technical considerations when obtaining the cardiac stem cells after myocardial infarction in patients enrolled in the CADUCEUS trial. RESULTS From January 2002 to December 2005, 754 biopsy procedures were performed in 179 patients after OHT with the bicaval technique, using bioptome A. There was 1 occurrence of ventricular fibrillation requiring cardioversion, and no occurrence of cardiac tamponade during the procedure. From January 2006 to September 2013, 2818 biopsy procedures were performed in 1064 patients using bioptome B. No patient developed ventricular fibrillation or cardiac tamponade during the procedure. In 2010 and 2011, 23 biopsy procedures were performed in 23 patients after acute myocardial infarction, using bioptome B. No immediate complications occurred while performing these biopsies. The late occurrence of tricuspid regurgitation was not evaluated in this study. CONCLUSIONS Endomyocardial biopsy procedures can be safely performed after OHT with the bicaval technique and after myocardial infarction for harvesting of cardiac stem cells. Ultrasound guidance for vascular access, a long guidewire and sheath, and a flexible bioptome are important features for the safe conduct of the biopsy procedure.