Ten year survival after heart transplantation: palliative procedure or successful long term treatment?

Prenatal Screening, Ethics and Down’s Syndrome: a literature review

This article reviews the literature on prenatal screening for Down’s syndrome. To be evidence based, medicine and nursing have to take account of research evidence and also of how this evidence is processed through the influence of prevailing social and moral attitudes. This review of the extensive literature examines how appropriate widely-held understandings of Down’s syndrome are, and asks whether or not practitioners and prospective parents have access to the full range of moral arguments and social evidence on the matter. Highly valued ideals of justice, personal autonomy, parental choice, women’s control over their reproduction and of avoiding harm can all tend towards negative rather than neutral approaches to Down’s syndrome. This article considers how ethics and prenatal screening policies and practice that take greater account of social evidence of disability could use moral arguments that inform rather than determine the choices of people who use prenatal services.

Prescription trends of immunosuppressive drugs in post-heart transplant recipients in Taiwan, 2000-2009

PURPOSE

Significantly increasing heart transplantations have been performed in Taiwan in the past decades, but the trends of maintenance immunosuppression for heart transplant recipients have not been well known. In this study, we aimed to explore the trends of maintenance immunosuppressive therapy and common complications for heart transplant recipients.

METHODS

We retrospectively analyzed ambulatory prescriptions in 488 heart transplant recipients for the period 2000-2009. Patient complications after heart transplantation were also identified.

RESULTS

The annual number of new heart transplant recipients ranged from 18 to 68. The 5-year survival rate was 77.9%. The total number of regimens was 10 in 2000, and increased to 28 in 2009. Most prescriptions were immunosuppressive combinations (95.5%-89.5%). The majority of immunosuppressive regimens were a triple regimen: cyclosporine, mycophenolic acid and corticosteroid in 2009. Cyclosporine was a predominant calcineurin inhibitor with a decreasing trend from 73.9% to 59.1%, whereas the use of tacrolimus significantly increased from 11.9% to 38.4%. Mycophenolic acid was the most frequently used antimetabolite (60.1%-80.3%), while the use of azathioprine was reduced (21.6%-2.3%). From 2008, the launch of everolimus initiated a new era in the utilization of mammalian target of rapamycin inhibitors for maintenance immunosuppression.

CONCLUSIONS

Cyclosporine remained the most frequently used calcineurin inhibitors, and tacrolimus increased gradually. Mycophenolic acid was the most popular antimetabolite rather than azathioprine. The rapidly increased everolimus combined regimen may change the patterns of maintenance immunosuppression. The increasing number of combination therapies indicates an active role of everolimus and a tendency of complex tailored individual therapies.

Ischemic cardiomyopathy: midterm survival and its predictors

BACKGROUND

the aim of the study was to analyze all-cause mortality and predictors of long-term survival after myocardial revascularization for ischemic cardiomyopathy.

METHOD

data of 101 patients (mean age, 63.86 years; age range, 30-85 years; 92% male), operated on with stable coronary artery disease and left ventricular ejection fraction <30% between April 2000 and June 2010, were analyzed.

RESULTS

operative mortality was 1.9% (2/101). There was a significant improvement in left ventricular ejection fraction from 25.99% ± 3.8% preoperatively to 34% ± 12% postoperatively (p <0.0001). The mean duration of follow-up was 56.3 ± 33 months, and it was 97% complete (98/101). There were 18/96 (18.75%) late deaths. Overall actuarial survival at 1, 3, 5, and 10 years was 96%, 89%, 83% and 75%, respectively. Univariate predictors of late death were preoperative arrhythmia, cerebrovascular disease, peripheral vascular disease, and logistic EuroSCORE. Multivariate predictors of late death were cerebrovascular disease and preoperative arrhythmia.

CONCLUSION

our study suggests that myocardial revascularization for ischemic cardiomyopathy improves left ventricular ejection fraction and is associated with favorable long-term survival. Patients with cerebrovascular disease and preoperative arrhythmias had poorer outcomes.

Diagnostic performance of multisequential cardiac magnetic resonance imaging in acute cardiac allograft rejection

AIMS

We evaluated cardiac magnetic resonance imaging (CMR) as a non-invasive test for cardiac allograft rejection.

METHODS AND RESULTS

We performed CMR on 50 heart-transplant recipients. Acute rejection was confirmed in 11 cases by endomyocardial biopsy (EMB) and presumed in 8 cases with a recent fall in left-ventricular ejection fraction (LVEF) not attributable to coronary allograft vasculopathy. Control patients had both normal LVEF and no significant rejection on EMB. Cardiac magnetic resonance imaging evaluated myocardial function, oedema, and early and late post-Gadolinium-DTPA contrast enhancement. Patients with confirmed rejection demonstrated elevated early relative myocardial contrast enhancement (4.1 +/- 0.3 vs. 2.8 +/- 0.2, P < 0.001) and a trend to higher oedema suggested by higher relative myocardial intensity on T(2)-weighted imaging compared to controls (2.1 +/- 0.1 vs. 1.7 +/- 0.1, P = 0.1). With rejection defined as increased early contrast enhancement or myocardial oedema, the sensitivity and specificity of CMR compared with EMB were 100 and 73%, respectively. Eight patients with presumed rejection also had elevated early myocardial contrast enhancement compared with controls, (8.7 +/- 1.9 vs. 2.8 +/- 0.2, P < 0.05), which reduced following increased immunosuppression (8.7 +/- 1.9 vs. 4.6 +/- 1.2, P < 0.05). In these patients LVEF improved following increased immunosuppression (32 +/- 5 vs. 46 +/- 5%, P < 0.05).

CONCLUSION

Cardiac magnetic resonance imaging is a promising modality for non-invasive detection of cardiac allograft rejection.

Amiodarone-induced QT prolongation in a newly transplanted heart associated with recurrent ventricular fibrillation

Anti-arrhythmic drugs such as amiodarone have the potential to prolong QT intervals, which can result in torsades de point arrhythmia. It is unknown whether amiodarone, given to a recipient prior to cardiac transplantation, can cause arrhythmia in a newly transplanted donor heart. We report on a case of a 71-year-old male patient who had received intravenous and oral amiodarone prior to transplantation, which wasassociated with QT prolongation in the transplanted heart after re-exposure to the drug during subsequent episodes of ventricular fibrillation. An ICD was implanted, which has not been described that soon after cardiac transplantation. Amiodarone, given to a recipient, might cause QT prolongation in a donor heart after transplantation, possibly due to its long half-life and increased bioavailability caused by interaction with immunosuppressive drugs.

Influence of different implantation techniques on long-term survival after orthotopic heart transplantation: an echocardiographic study

BACKGROUND

Orthotopic heart transplantation (OHT) was initially done by the biatrial technique, although the bicaval technique has recently become more popular. The aim of this study was to compare OHT outcomes when using the bicaval technique vs the biatrial technique.

METHODS

A total of 615 patients were transplanted at the Cleveland Clinic Foundation from January 1993 and October 2003 (biatrial technique: n = 293; bicaval technique: n = 322). The average follow-up period was 4.2 +/- 2.9 years (range 1 to 11 years). Patients who were supported with a left ventricular assist device (prior to transplant) and who could not be weaned off respiratory support were excluded.

RESULTS

Patients in both groups were similar with regard to pre-operative characteristics. The peri-operative mortality showed no statistical significant differences between the two groups. The left atrium was significantly more enlarged in the biatrial group. The bicaval group showed a significantly reduced incidence of tricuspid regurgitation. Survival at 10-year follow-up was 87.3% in the bicaval group and 79.9% in the biatrial group (p < 0.05). Left ventricular ejection fraction (LVEF), right ventricular ejection fraction (RVEF) and moderate to severe tricuspid regurgitation were significant risk factors for death in both groups. The bicaval technique showed a significantly better mortality outcome.

CONCLUSIONS

This study showed that the bicaval technique for OHT offers a better outcome than the biatrial technique. The significant reduction of left atrial size and atrioventricular valve regurgitation in the bicaval group may have a major impact on the long-term preservation of cardiac function and survival.

Risk stratification for renal transplantation after cardiac or lung transplantation: single-center experience and review of the literature

BACKGROUND

Long-term survival after heart (HTx) or lung (LuTx) transplantation increases the risk for end-stage renal disease (ESRD). After HTx ESRD was reported to enhance mortality, and kidney transplantation (KTx) was shown to improve survival. However, prognostic factors in ESRD after HTx or LuTx are largely unknown.

METHODS

Single-center observational study in HTx and LuTx patients who accessed the KTx waiting list; baseline characteristics were correlated with mortality.

RESULTS

KTx was performed in 15 of 65 study patients. Survival was comparable on the KTx waiting list and in reference patients from the same center without ESRD. KTx significantly improved survival (5 years' survival 84.6% with KTx vs. 56.5% on the KTx waiting list, p = 0.030). None of the baseline parameters predicted mortality in the KTx group. Only on the KTx waiting list BMI (median 24.7 vs. 20.7; p < 0.05) and left ventricular ejection fraction (LVEF, median 63 vs. 53%, p < 0.008) significantly correlated with survival.

CONCLUSIONS

The risk for mortality after HTx or LuTx is not increased by ESRD, provided that patients meet access criteria for the KTx waiting list. KTx improves survival in ESRD after HTx or LuTx. BMI and LVEF may predict outcome in HTx/LuTx patients on the KTx waiting list.

Heart transplant and left ventricular assist device costs

BACKGROUND

With the increasing clinical success of left ventricular assist devices (LVADs), physicians need to measure device cost efficacy to determine the societal value of this technology. Today's large clinical volume allows comparison of the costs of this innovation as compared with orthotopic heart transplant (OHT).

METHODS

We evaluated hospital cost and reimbursement for patients who were discharged after LVAD implantation and returned to the hospital for OHT. To control for patient-specific variables, LVAD therapy and OHT therapy were compared in the same patient; that is, only those patients who received an LVAD were discharged, and returned for OHT were studied. Length of stay (LOS), re-admissions and outpatient services were analyzed, including their respective total actual hospital cost (TAHC) and net revenue (NR). Time periods analyzed were the same for LVAD and OHT.

RESULTS

From the LVAD population at Columbia-Presbyterian Medical Center, 36 patients were discharged following HeartMate vented electric (VE) implantation and re-admitted for OHT between December 1996 and June 2000. Mean pre-LVAD implantation LOS was 21.3 +/- 24.1 days. Post-LVAD LOS was 36.8 +/- 22.2 days vs 18.2 +/- 12.2 days post-OHT (p < 0.001). Mean length of LVAD support was 123.4 +/- 77.7 days. Overall total costs for LVADs exceeded that of OHT, whereas revenue was relatively lower. TAHC post-LVAD averaged $197,957 +/- 77,291, whereas TAHC post-OHT averaged $151,646 +/-53,909 (p = 0.005). NR averaged $144,756 +/- 96,656 post-LVAD vs $178,562 +/- 68,571 post-OHT (p = 0.09). LVAD patients had more re-admissions compared with OHT: 1.2/123 days (+/- 1.7) vs 0.3/123 days (+/- 0.6), respectively (p = 0.005). The average LOS during a re-admission was similar between the 2 groups (LVAD 5.6 days [+/- 10.6] vs OHT 9.6 days [+/- 8.2]; p = 0.18). OHT was associated with a significantly greater number of outpatient services compared with LVAD (9.7 [+/- 6.1] vs 3.0 [+/- 4.7]; p < 0.001). In contrast to OHT, revenues did not match the costs of LVAD therapy.

CONCLUSIONS

LVAD implantation is associated with longer LOS and higher cost for initial hospitalization compared with OHT. LVAD patients have higher re-admission rates compared with OHT but similar costs and LOS. OHT is associated with a greater number of outpatient services. Reimbursements for LVAD therapy are relatively low, resulting in significant lost revenue. If LVAD therapy is to become a viable alternative, improvements in both cost-effectiveness and reimbursement will be necessary.

Different clinical scenarios for circulatory mechanical support in acute and chronic heart failure

Chronic heart failure (HF) is a leading cause of death in developed countries. Over the last 2 decades, mechanical circulatory support (MCS) devices have steadily evolved in the clinical management of end-stage HF and have emerged as a standard of care for the treatment of acute and chronic HF refractory to conventional medical therapy. Possible indications for using MCS are acute cardiogenic shock, as a bridge to transplantation, as a bridge to recovery, and more recently, as destination therapy in dilated cardiomyopathy, of either ischemic or idiopathic etiology. We reviewed the different clinical scenarios in which we think there are currently indications to implant different kinds of MCS systems.

Low incidence of malignancy after transplantation in Chinese heart allograft recipients

This study sought to assess the incidence of neoplastic disease after transplantation in Chinese heart allograft recipients. A total of 156 patients (130 male and 26 female; mean age, 45.8 +/- 15.7 years), surviving more than 30 days after transplantation, were enrolled in this study. The mean follow up duration was 51.2 +/- 33.0 months. Six patients (3.8%) developed neoplastic diseases after transplantation: post-transplant lymphoproliferative diseases in four and solid tumors in two patients. There was no skin cancer or Kaposi's sarcoma. Solid tumors affected the prostate, liver and urinary bladder in two patients. The cumulative incidence of neoplastic disease was 2.1% at 1 year, 3.6% at 5 years, and 10.1% at 10 years after transplantation. The incidence of post-transplant neoplastic disease was low in Chinese heart allograft recipients. It resulted from a relative paucity of Kaposi's sarcoma and skin cancers in Chinese population.

Factors predicting 10-year survival after heart transplantation

BACKGROUND

We sought to identify factors predictive of long-term (>10-year) survival in heart transplant (HTx) recipients.

METHODS

Four hundred fifteen adult patients underwent HTx at our institution between August 1982 and May 1997. The 158 patients who survived >10 years (Group A) and the 116 patients who died between 2 and 6 years (Group B) of HTx were compared in terms of gender, gender mismatch, ethnicity, age, height, weight, United Network for Organ Sharing status, type of induction therapy (OKT3 or anti-thymocyte globulin), infections (bacterial, viral, fungal and protozoal), cytomegalovirus (CMV) status, CMV mismatch, diabetes mellitus, hypertension and incidence of rejection episodes and transplant coronary artery disease within 2 years of HTx.

RESULTS

Group A (135 men, 23 women; mean age 48 +/- 11 years) had significantly fewer post-HTx rejection episodes and viral, bacterial, fungal and total infections than did Group B (95 men, 21 women; mean age 49 +/- 12 years). Group A also had a significantly lower mean donor age, a lower incidence of pre-HTx diabetes, and a lower mean cholesterol level 1 year after HTx. In a multivariate analysis, fewer bacterial infections and rejection episodes after HTx, the absence of pre-HTx diabetes, and lower donor age were associated with longer survival.

CONCLUSIONS

Pre-HTx diabetes, donor age and incidences of infection and rejection within 2 years of HTx predict long-term (>10-year) survival. Better control of infection and rejection during the first 2 years after HTx may improve survival.

Pravastatin therapy is associated with reduction in coronary allograft vasculopathy in pediatric heart transplantation

BACKGROUND

Hydroxymethylglutaryl CoA reductase inhibitors (statins) have been demonstrated to reduce the risk of developing coronary allograft vasculopathy (CAV) following heart transplantation in adults and are used routinely in many centers. CAV and lipid abnormalities have been reported to be less prevalent in pediatric heart transplant recipients. It is not known whether statins reduce the risk of CAV in this population

METHODS

A retrospective review was performed to analyze the risk factors for developing CAV following pediatric heart transplantation with particular attention to the impact of pravastatin therapy. The study population was comprised of 129 pediatric patients who underwent 142 heart transplants at our institution from 1988 to 2003. The outcome variable was freedom from CAV, CAV being determined by coronary angiography or autopsy.

RESULTS

CAV was identified in 25 recipients at a median of 3.7 years after transplantation. There were 331 patient-years of pravastatin therapy. Pravastatin therapy resulted in a reduction in total cholesterol levels, 162 +/- 29 to 137 +/- 20 mg/dl, p = 0.01. In multivariate analysis the use of pravastatin was associated with a lower incidence of CAV (p = 0.03), whereas an increased frequency of late rejection (p = 0.003) and earlier year of transplantation (p = 0.04) were associated with increased risk of CAV.

CONCLUSIONS

The routine use of pravastatin was associated with a lower risk following pediatric heart transplantation. Further studies into the relationship between lipid abnormalities, inflammation and rejection, and the development of CAV in children are warranted.

Clinical usefulness of bronchoalveolar lavage in heart transplant recipients with suspected lower respiratory tract infection

BACKGROUND

Bronchoscopy with bronchoalveolar lavage (BAL) is the recommended initial invasive diagnostic procedure when lower respiratory tract infection is suspected in solid-organ transplant recipients. In this study, we evaluated the clinical impact and safety of bronchoscopy with BAL in heart transplant recipients.

METHODS

We reviewed all 44 consecutive diagnostic bronchoscopies with BAL that were performed in 35 heart transplant recipients at Helsinki University Central Hospital between May 1988 and December 2001.

RESULTS

Bronchoscopy findings established specific microbiologic diagnoses in 18 of 44 (41%) cases, and 14 of 44 (32%) bronchoscopic findings led to changes in therapy. The diagnostic yield of bronchoscopy from 1 to 6 months after transplantation was 73%, significantly better (p = 0.002) than diagnostic yield during the first month (18%) and after 6 months (28%). Pneumocystis carinii and cytomegalovirus were the most frequently detected pathogens in the BAL fluid. Cytomegalovirus pneumonia carried a high mortality rate (44%), whereas all patients with P carinii pneumonia recovered. Fourteen episodes were diagnosed as bacterial pneumonia, but because of empiric antibiotic therapy that was started widely before bronchoscopy, a microbiologic diagnosis was established in only 1 case. However, all patients with community-acquired pneumonia responded to empiric therapy. Four cases of major complications occurred after bronchoscopy, all cardiovascular but none fatal.

CONCLUSIONS

Bronchoscopy with BAL is a useful diagnostic tool in heart transplant recipients, especially between 1 and 6 months after transplantation.

Delayed occurrence of cardiac allograft vasculopathy in Chinese heart transplant recipients compared with their western counterparts

Cardiac allograft vasculopathy (CAV) is a leading limiting factor to long-term survival after cardiac transplantation. We investigated the prevalence of CAV and its associated factors in Chinese heart transplant recipients. From July 1987 to July 2000, we performed 140 consecutive heart transplantations at the National Taiwan University Hospital. Of the 140 patients, 98 who were > or = 17-yr old at the time of transplantation, had survived for more than 1 yr after transplantation, and who had normal findings at the 1-month coronary angiogram study, were included in this study. Group I consisted of 25 patients who eventually developed CAV in the follow-up, and group II consisted of 73 patients who were free from CAV in the follow-up. CAV was defined by coronary angiogram study.The donor and recipient characteristics were not statistically different between the two groups except the older donor age (p = 0.02), higher first-year mean rejection score (p = 0.03) and more prevalent cytomegalovirus infection rate (p = 0.03) in group I. Multivariate Cox regression analysis revealed that only higher first-year mean rejection score (p = 0.01), and older donor age (p = 0.04) were important risk factors for developing CAV. The 1-5 yr of actuarial freedom from the presence of CAV were 97, 93, 86, 80 and 69% in our study patients. In summary, these data show that CAV occurred later in Chinese heart transplant recipients in comparison with their western counterparts, but the risk factors for developing CAV were not different.

Drug immunosuppression therapy for adult heart transplantation. Part 1: immune response to allograft and mechanism of action of immunosuppressants

In the early days of transplantation, immunosuppression therapy was rather broad and nonspecific, mainly using high-dose corticosteroids and azathioprine. Thereafter we progressively narrowed the target of immunosuppressive strategy starting with polyclonal antibodies. The introduction of cyclosporine, OKT3, and tacrolimus further narrowed the target on the T-cell pathways. More recently mycophenolate mofetil progressively took the place of azathioprine with its higher lymphocyte specificity and sirolimus and interleukin-2 receptor antibodies were introduced. In this field in constant movement the aim is to find a drug or a regimen that provides optimal immunosuppression therapy with minimal side effects, in other words to find the right balance between overimmunosuppression and underimmunosuppression therapy. This review is divided into two parts. The first part will provide a basic understanding of the immunologic response to allograft and explain how conventional and recently introduced immunosuppressive agents work. The second part will describe the clinical application of immunosuppressive drugs to provide practical information for those in charge of heart transplant recipients.

Clinical and Exercise Test Determinants of Survival After Cardiac Transplantation *

BACKGROUND

Cardiac transplantation (CTX) is now a viable option for patients with end-stage heart failure, but there remains a paucity of available donor hearts relative to the demand for them. Establishing prognosis after CTX can help direct this resource to patients most likely to benefit, as well as to help guide therapy for CTX recipients. Clinical, exercise, and hemodynamic factors associated with survival after CTX have not been well established.

METHODS

One hundred seventy-four randomly selected patients who underwent heart transplantation between 1983 and 1999 at Rikshospitalet University Hospital were included in the study. Data were collected as a part of routine posttransplantation management a mean of 3.5 +/- 2.1 years (+/- SD) after CTX. Clinical, cardiopulmonary exercise testing, and hemodynamic measures were performed, including measures of peak oxygen uptake (O(2)), ejection fraction, cardiac index, pulmonary capillary wedge pressure (PCWP), pulmonary artery pressure, creatinine, and the presence of coronary artery disease. Patients were followed up for a mean of 7.1 +/- 2.1 years; all-cause mortality was used as the end point for survival analysis.

RESULTS

During the follow-up period, 39 patients died; the average annual mortality was 3.6%. Peak O(2) was 19.6 +/- 5.6 mL/kg/min, representing 70.5 +/- 6.7% of the age-predicted value. Only right atrial pressure and PCWP differed between those who survived and those who died; both were slightly higher among those who died. By Cox proportional hazard analysis, there were no age-adjusted univariate or multivariate predictors of survival among continuous variables. Exploring various cut points revealed that serum creatinine > 118 micromol/L, PCWP > 12 mm Hg, and mean pulmonary artery pressure > 25 mm Hg were significant univariate predictors of mortality. These cut points for PCWP and pulmonary artery pressure generated hazard ratios of 2.3 and 2.9, respectively.

CONCLUSION

Long-term survival after CTX was comparatively high in our cohort, with 5-year survival > 80%. Standard clinical, hemodynamic, and cardiopulmonary exercise test variables were not strong predictors of mortality in CTX patients a mean of 7 years after CTX. The association between elevated hemodynamic pressures and mortality, although weak, suggests that ventricular compliance, pulmonary vascular resistance, or both, may predict long-term survival after CTX.

Combined study with FDG PET and Tl SPECT in patients with idiopathic dilated cardiomyopathy

This study aimed to determine whether combined examinations of myocardial 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG PET) and stress-redistribution 201Tl single-photon emission computed tomography (Tl SPECT) were useful in clarifying myocardial ischaemia and evaluating the prognosis in patients with idiopathic dilated cardiomyopathy (IDCM). Twenty-two patients with IDCM underwent echocardiography, cardiac catheterization, FDG PET, and Tl SPECT. In scintigraphic analysis, the total defect score (TDS) was semiquantitatively determined as the sum of scores of the 17 left ventricular (LV) segments with a 5-point scale (0 as normal to 4 as absent). Patients were classified according to the scintigraphic findings as follows: eight patients with small defects on Tl and FDG (TDS < or = 20) (group I), eight patients with small defects on FDG (TDS < or = 20) with FDG uptake increased relative to Tl or 'mismatch' (group II), and six patients with large defects on FDG and Tl (TDS >20) (group III). Eleven patients (50%) showed reversible defects on Tl and all showed preserved FDG uptake. The patients in group III had significantly lower LV ejection fraction (LVEF) (P<0.05, respectively) and a poorer prognosis as shown by the Kaplan-Meier event-free curve compared with those in groups I and II (P<0.01, respectively). Although patients in group II had significantly greater TDS on Tl compared with those in group I (P<0.01), no significant differences in LVEF and prognosis were found between patients in groups I and II. In multivariate analysis, a TDS on FDG revealed an independent predictor of subsequent cardiac events. In conclusion, such mismatched areas can be assumed to consist of impaired but viable myocardium, and may be associated with ischaemia of the microvasculature. Impaired myocardial glucose metabolism is a more powerful predictor of future cardiac events than perfusion abnormality in patients with IDCM.

Non-invasive detection of coronary artery disease by dobutamine-stress echocardiography in children after heart transplantation

BACKGROUND

Coronary vasculopathy is the main cause of cardiac graft failure. Because yearly coronary angiography is invasive in children, a non-invasive method for detecting graft vasculopathy is needed. The aim of this study was to test dobutamine-stress echocardiography in a pediatric population to determine its feasibility, safety and reliability in the detection of graft coronary artery disease.

METHODS

Eighteen patients, aged 2 days to 16.8 years at transplantation (mean 8.4 years), underwent 44 dobutamine-stress echocardiography (DSE) exams, at a follow-up of 1.1 to 11.8 years (mean 5.1 years). Selective coronary angiography was performed for comparison. Echocardiographic recordings were obtained in 4 standard views of the left ventricle and measurements carried out within the frames of a 16-segment model. Segmental scores of contractility were obtained for each segment and a total segmental contractility index was calculated at each stage.

RESULTS

All patients reached the maximum dose stage. Maximum heart rate was 57% to 90% of predicted maximum. Maximum systolic blood pressure reached 190 mmHg. Segmental scores were normal in 37 and abnormal in 7 cases. Echographic results were concordant with angiography in 82% and discordant in 18% of the cases (4 negative DSEs with minor angiographic lesions, 2 positive DSEs with normal angiography), but there was no significant angiographic lesion with normal DSE.

CONCLUSIONS

DSE is a safe and highly feasible non-invasive technique in transplanted children. A normal DSE study successfully predicts the absence of significant coronary artery disease in the post-transplant population.

Radionuclide viability testing: should it affect treatment strategy in patients with cardiomyopathy and significant coronary artery disease?

BACKGROUND

Ischemic heart failure is a significant source of morbidity and mortality, yet it has an unclear treatment strategy. The assessment of viable myocardium by nuclear imaging studies has shown promise in predicting improvements in ejection fraction and symptoms. However, the relationship of viability to long-term mortality has not been fully established.

METHODS

A number of studies have addressed long-term mortality with nuclear viability imaging in patients with impaired left ventricular function and significant coronary artery disease. These studies were analyzed to determine differences in design, results, trends, and limitations. They were then evaluated by use of qualitative criteria established for prognostic studies.

RESULTS

Fourteen studies met our criteria. Although the conclusions differed, it appears that patients with viability who undergo revascularization have the highest survival rate, whereas patients with viability who are treated medically have a much lower survival rate. Patients without viability have an intermediate survival rate, regardless of treatment. Several limitations were identified, including a lack of randomization, small sample size, inadequate follow-up, and extensive study protocol and design differences.

CONCLUSIONS

The use of viability testing in patients with heart failure and significant coronary artery disease has shown promise in predicting the long-term mortality rate with treatment allocation. However, there is a need for further study involving larger cohorts with a randomized design, longer periods of follow-up, improved study designs, and identification of referral bias and viability prevalence.

Heart transplantation: echocardiographic assessment of morphology and function after more than 10 years of follow-up

BACKGROUND

Over recent years, heart transplantation (HTX) developed into a successful option for long-term treatment of end-stage heart failure. Ten-year survival ranges between 40% and 50%. Little is known, however, about function and morphology of transplanted hearts during follow-up of more than 10 years.

METHODS

In a consecutive cohort of 65 patients (55 male, 54.6 +/- 12.1 years at the time of transplantation), graft function was assessed by color Doppler echocardiography 12.5 +/- 1.4 years after heart transplantation (10 to 15 years).

RESULTS

Left atrial and ventricular dimensions were found in a normal range (LA 37.7 +/- 8.9 mm, LV enddiastolic 45.6 +/- 6.4 mm, 30 to 71 mm). Ejection fraction (EF) of 71 +/- 11.7% and a fractional shortening of 35.3 +/- 10.3% presented with normal values. Left ventricular mass (male 263.8 +/- 111.4 g, female 373.0 +/- 181.1 g) was slightly increased resulting in mild hypertrophy in women. Focused on right ventricular morphology, enlargement of both the right atrium and the right ventricle (RA 40.7 +/- 11.8 mm, RV 37.4 +/- 8.3 mm) was observed in the majority of the patients. Tricuspid valve insufficiency (> grade II) was present in 46 of 65 patients; 5 patients had previously undergone tricuspid valve replacement. Atrial filling waves were detectable in only 47 of 65 patients, thus, 28% of patients showed signs of LA-dysfunction.

CONCLUSIONS

More than 10 years post-HTX, cardiac grafts were characterized by normal left ventricular dimensions and ejection fraction. LA-dysfunction and RV-enlargement associated with tricuspid insufficiency were frequent findings, however, not associated with clinical signs of congestive heart failure in the majority of patients.

The paradox of survival results after heart transplantation for cardiomyopathy caused by Trypanosoma cruzi. First Guidelines Group for Heart Transplantation of the Brazilian Society of Cardiology

BACKGROUND

Donor supply limits heart transplantation (HT) and relative priority should be given to cases with greater chances of success. The objectives of this multicenter study were (1) to determine the survival rate after heart transplantation for patients with Chagas' heart disease (ChHD) in comparison with other causes; and (2) to identify the causes of death specifically due to reactivation of the Trypanosoma cruzi infection.

METHODS

We studied 720 patients who had undergone orthotopic heart transplantation and were followed in 16 heart transplantation centers. The etiology was idiopathic dilated cardiomyopathy in 407 patients, ischemic cardiomyopathy in 196 patients, and ChHD in 117 patients.

RESULTS

Follow-up was 2.87 +/- 3.05 years (from 1 month to 13.85 years). Survival of ischemic recipients at 1, 4, 8, and 12 years was 59%, 44%, 34%, and 22%, respectively; for idiopathic dilated cardiomyopathy it was 69%, 57%, 40%, and 32%; and for ChHD it was 71%, 57%, 55%, and 46% (p < 0.027). In ischemic recipients the most frequent causes of death were infection (15.3%), acute graft failure (13.3%), and graft coronary artery disease/sudden death (7.7%). In idiopathic dilated cardiomyopathy the causes were infection (11.1%), rejection (9.6%), and acute graft failure (9.1%). In ChHD the causes were infection (10.3%), rejection (10.3%), and neoplasm (4.3%). In ChHD, reactivation of the cruzi infection was the cause of death in 2 patients.

CONCLUSIONS

The survival results after heart transplantation are paradoxical according to the usually high expected death rates for Chagas' disease. Heart transplantation for ChHD should be regarded as a valuable treatment option.

The Brazilian experience with heart transplantation: a multicenter report

BACKGROUND

The results of heart transplantation in developing countries are influenced by the high incidence of marginal donors and the large number of recipients with characteristics of alternative list. The purpose of this multicenter report was to determine the rate of survival after heart transplantation in a developing country. Also we studied the causes of death, the results based on the year of transplant, the influence of gender and age, the numbers of transplants per year, and the etiology of the cardiomyopathy causing the heart failure.

METHODS

We studied 792 (632 male) patients who underwent orthotopic heart transplantation at 16 centers. The mean age of the patients was 42 +/- 16 years. Etiology included idiopathic dilated cardiomyopathy in 407 patients, ischemia in 196 patients, Chagas disease in 117 patients, and various other in 72 patients. Cyclosporine was the cornerstone of the immunosuppression administered.

RESULTS

Survival for the entire population at 3 months and 1, 4, 8, and 12 years was 72%, 66%, 54%, 40%, and 27%, respectively. There was an improvement in survival from 1991 to 1995 compared with before 1991. Age and gender did not influence the results. Unexpected early mortality was observed, but the late results were satisfactory. The most prevalent causes of death were infection in 23%, acute graft failure in 19%, and rejection in 18%.

CONCLUSIONS

Heart transplantation has become feasible in developing countries and the survival rate has improved without the influence of gender and age recipients. A chagasic etiology was found to be the third-leading indication for heart transplantation. The impact of increment of donors with appropriate care for reduction of marginal donors, perhaps associated with better recipient selection and postoperative care, should be investigated for improving early results.

Impact of heart transplantation on the safety and feasibility of the dobutamine stress test

BACKGROUND

Dobutamine myocardial perfusion imaging is a useful method for evaluation of coronary artery disease. However, this technique does not allow for ischemia monitoring, which may have an impact on the safety of the test in heart transplant recipients due to cardiac sensory denervation. The aim of this study was to assess the impact of heart transplantation on the feasibility and complications of the dobutamine stress test.

METHODS

We studied 225 heart transplant recipients (mean age 57 +/- 7 years) and a control group of 225 patients without previous transplant matched for age and gender by dobutamine (up to 40 microg/kg per minute) stress myocardial perfusion imaging.

RESULTS

During the test, transplant recipients had a lower prevalence of premature ventricular contractions (23% vs. 37%, p < 0.001) and ventricular tachycardia (0.04% vs 7.5%, p < 0.0001) compared with control patients. By multivariate analysis, heart transplantation was a powerful independent variable associated with a reduced risk of ventricular arrhythmias (chi(2) = 20.8, p < 0.0001) and minor side effects (nausea, dizziness, anxiety, flushing, chills) (chi(2) = 20, p < 0.0001) during dobutamine stress. The target heart rate was reached in 82% of transplant recipients and in 77% of the control group. Overall feasibility (achievement of the target heart rate and/or an ischemic end-point) was 87% in the transplant and 86% in the control group.

CONCLUSIONS

Dobutamine stress myocardial perfusion imaging is a safe and feasible method for evaluation of coronary artery disease in heart transplant recipients. The prevalence of arrhythmias and minor complications using the dobutamine stress test is lower in heart transplant recipients compared with control patients. The independent association between heart transplantation and reduced risk of arrhythmias and minor side effects of the dobutamine stress test indicates that cardiac sensory and autonomic nerve function plays a major role in the induction of these complications during the test.