Elevated Cardiac Troponin I in Preservation Solution Is Associated With Primary Graft Dysfunction

BACKGROUND

Although primary graft dysfunction (PGD) is a leading cause of mortality and morbidity early post-heart transplant, relatively little is known regarding mechanisms involved in PGD development.

METHODS AND RESULTS

We examined the relationship between cardiac troponin I (cTnI) concentrations in the preservation solution from 43 heart transplant procedures and the development of PGD. Donor hearts were flushed with cold preservation solution (University of Wisconsin [UW] or Custodiol) and stored in the same solution. cTnI concentrations were measured utilizing the i-STAT System and normalized to left ventricular mass. Recipient medical records were reviewed to determine PGD according to the 2014 ISHLT consensus conference. Nineteen patients developed PGD following cardiac transplantation. For both UW and Custodiol, normalized cTnI levels were significantly increased (P = .031 and .034, respectively) for those cases that developed PGD versus no PGD. cTnI levels correlated with duration of ischemic time in the UW group, but not for the Custodiol group. Donor age and donor cTnI (obtained prior to organ procurement) did not correlate with preservation cTnI levels in either UW or Custodiol.

CONCLUSIONS

Increased preservation solution cTnI is associated with the development of PGD suggesting preservation injury may be a dominant mechanism for the development of PGD.

Scedosporium apiosermum infection of the "Native" valve: Fungal endocarditis in an orthotopic heart transplant recipient

Scedosporium apiospermum is an increasingly appreciated pathogen in immunosuppressed patients. We present a case of S. apiospermum endocarditis in a 70-year-old male who had undergone orthotopic heart transplant. Echocardiogram demonstrated a 1.4 cm tricuspid valve vegetation. He underwent valve replacement, complicated by fatal massive post-operative haemorrhage. Valve cultures grew S. apiospermum. To our knowledge, our case is the first reported instance of endocarditis caused by S. apiospermum in a recipient of a cardiac transplant.

Improved early survival with a nonsternotomy approach for continuous-flow left ventricular assist device replacement

BACKGROUND

Even in the modern era of continuous-flow left ventricular assist devices (CF LVADs), device replacement may be required. Nonsternotomy (NS) approaches are being used more commonly for replacement procedures. Outcomes after this less invasive approach compared with those after a reoperative sternotomy (RS) have not been extensively studied. Furthermore, the clinical impact of concurrent cardiac procedures during device replacement has not been examined.

METHODS

From 2005 to 2013, all consecutive implantable LVAD procedures were reviewed, and those using CF devices as both the initial and replacement device were identified. These CF LVAD replacement procedures were divided into those using an RS and those using an NS approach. Periprocedural morbidity and mortality were compared between the groups.

RESULTS

A total of 42 CF LVAD replacements were performed in 39 patients, with 20 using an RS approach and 22 using an NS approach. Eleven of the 20 replacement procedures performed by RS included a concurrent cardiac procedure. Relative to the RS cohort, the NS approach was associated with shorter cardiopulmonary bypass time, reduced length of mechanical ventilation, decreased transfusion requirements, less inotropic support, decreased incidence of right ventricular (RV) dysfunction, and shorter intensive care unit (ICU) and overall hospital stays. An NS approach was also associated with improved 30- and 90-day survival (100% versus 79.0% in the RS group; p = 0.048). RS replacement procedures appeared to be associated with increased morbidity, regardless of whether they included concurrent cardiac procedures.

CONCLUSIONS

Patients who did not require an RS approach and who underwent CF LVAD replacement through an NS approach had improved survival and reduced morbidity compared with those who required an RS.

The palliative care in heart failure trial: rationale and design

BACKGROUND

The progressive nature of heart failure (HF) coupled with high mortality and poor quality of life mandates greater attention to palliative care as a routine component of advanced HF management. Limited evidence exists from randomized, controlled trials supporting the use of interdisciplinary palliative care in HF.

METHODS

PAL-HF is a prospective, controlled, unblinded, single-center study of an interdisciplinary palliative care intervention in 200 patients with advanced HF estimated to have a high likelihood of mortality or rehospitalization in the ensuing 6 months. The 6-month PAL-HF intervention focuses on physical and psychosocial symptom relief, attention to spiritual concerns, and advanced care planning. The primary end point is health-related quality of life measured by the Kansas City Cardiomyopathy Questionnaire and the Functional Assessment of Chronic Illness Therapy with Palliative Care Subscale score at 6 months. Secondary end points include changes in anxiety/depression, spiritual well-being, caregiver satisfaction, cost and resource utilization, and a composite of death, HF hospitalization, and quality of life.

CONCLUSIONS

PAL-HF is a randomized, controlled clinical trial that will help evaluate the efficacy and cost effectiveness of palliative care in advanced HF using a patient-centered outcome as well as clinical and economic end points.

Characteristics and outcomes of patients with heart failure and discordant findings by right-sided heart catheterization and cardiopulmonary exercise testing

There are limited data integrating findings on right-sided cardiac catheterization and cardiopulmonary exercise testing in ambulatory patients with heart failure. In this study, 187 outpatients with HF referred to the Duke Medical Center for consideration of advanced HF therapies were retrospectively evaluated. All patients had undergone right-sided cardiac catheterization and cardiopulmonary exercise testing; the median cardiac index (CI) was 2.0 L/min/m2 (interquartile range 1.7 to 2.3), and the median peak oxygen consumption was 11.3 ml/kg/min (interquartile range 9.2 to 13.8). Despite aggressive medical therapy, medical management had failed in 97 patients (52%) at 18 months, defined as left ventricular assist device implantation, cardiac transplantation, or death. After multivariate adjustment, factors associated with failure of optimal medical management included percentage achieved of predicted peak oxygen consumption, low CI (i.e., <2 L/min/m2), left ventricular size, and exercise time. Patients with discordant findings on right-sided cardiac catheterization and cardiopulmonary exercise testing were common, occurring in 88 patients (47%). The most common profile was preserved CI but reduced functional capacity, and these patients remained at high risk for requiring advanced therapies, whereas patients with reduced CIs but preserved exercise capacity were uncommon. In conclusion, low CI was independently associated with higher rates of death, transplantation, and left ventricular assist device implantation in this study. Also, patients with preserved CIs at rest but poor functional capacity, so-called cardiac insufficiency, were commonly encountered and had poor outcomes with medical management.

Trends in the use and outcomes of ventricular assist devices among medicare beneficiaries, 2006 through 2011

OBJECTIVES

This study sought to examine trends in mortality, readmission, and costs among Medicare beneficiaries receiving ventricular assist devices (VADs) and associations between hospital-level procedure volume and outcomes.

BACKGROUND

VADs are an option for patients with advanced heart failure, but temporal changes in outcomes and associations between facility-level volume and outcomes are poorly understood.

METHODS

This is a population-based, retrospective cohort study of all fee-for-service Medicare beneficiaries with heart failure who received an implantable VAD between 2006 and 2011. We used Cox proportional hazards models to examine temporal changes in mortality, readmission, and hospital-level procedure volume.

RESULTS

Among 2,507 patients who received a VAD at 103 centers during the study period, the in-hospital mortality decreased from 30% to 10% (p < 0.001), the 1-year mortality decreased from 42% to 26% (p < 0.001), and the all-cause readmission was frequent (82% and 81%; p = 0.70). After covariate adjustment, in-hospital and 1-year mortality decreased (p < 0.001 for both), but the all-cause readmission did not change (p = 0.82). Hospitals with a low procedure volume had higher risks of in-hospital mortality (risk ratio: 1.72; 95% confidence interval [CI]: 1.28 to 2.33) and 1-year mortality (risk ratio: 1.55; 95% CI: 1.24 to 1.93) than high-volume hospitals. Procedure volume was not associated with risk of readmission. The greatest cost was from the index hospitalization and remained unchanged ($204,020 in 2006 and $201,026 in 2011; p = 0.21).

CONCLUSIONS

Short- and long-term mortality after VAD implantation among Medicare beneficiaries improved, but readmission remained similar over time. A higher volume of VAD implants was associated with lower risk of mortality but not readmission. Costs to Medicare have not changed in recent years.

Ten-year experience with extended criteria cardiac transplantation

BACKGROUND

Extended criteria cardiac transplant (ECCT) programs expand the transplant pool by matching donors and recipients typically excluded from the transplant process because of age or comorbidity. There is a paucity of data examining long-term outcomes with this strategy.

METHODS AND RESULTS

Between January 2000 and December 2009, adult patients undergoing isolated heart transplant were prospectively classified as ECCT based on prespecified criteria. Baseline characteristics and outcomes were compared between ECCT and standard criteria cardiac transplant recipients. Two Cox proportional hazards models were developed. The first to identify clinical variables contributing to survival between the 2 groups, and the second to determine the additional risk associated with assignment to ECCT. Among the 454 patients who underwent heart transplant, 84 (18.5%) were ECCT. Compared with the patients who underwent standard criteria cardiac transplant, ECCT patients were older (median, 66.6 years versus 53.2 years; P<0.001), with higher frequency of diabetes mellitus (46.4% versus 24.6%; P<0.001) and chronic kidney disease (median estimated glomerular filtration rate, 55 versus 61.6 mL/min; P=0.001). After adjustment for baseline characteristics, standard criteria cardiac transplant survival was higher than ECCT at 1 (89% versus 86%; P=0.18) and 5 (77% versus 66%; P=0.035) years. In a multivariate model that included listing criteria, creatinine (hazard ratio, 1.05 per 0.1 mg/dL; 95% confidence interval, 1.02-1.09; P=0.001) was a significant predictor of post-transplant mortality.

CONCLUSIONS

ECCT is an acceptable alternative for advanced heart failure therapy in select patients. Age and renal dysfunction are important determinants of long-term survival and post-transplant morbidity.

Relationship of Right- to Left-Sided Ventricular Filling Pressures in Advanced Heart Failure

Background—

Although right atrial pressure (RAP) and pulmonary capillary wedge pressure (PCWP) are correlated in heart failure, in a sizeable minority of patients, the RAP and PCWP are not tightly coupled. The basis of this variability in the RAP/PCWP ratio, and whether it conveys prognostic value, is not known.

Methods and Results—

We analyzed the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) trial database. Baseline characteristics, including echocardiographic assessment of right ventricular (RV) structure and function, and invasively measured hemodynamic parameters, were compared among tertiles of the RAP/PCWP ratio. Multivariable Cox proportional hazard models assessed the association of RAP/PCWP ratio with the primary ESCAPE outcome (6-month death or hospitalization [days]) adjusting for systolic blood pressure, blood urea nitrogen, 6-minute walk distance, and PCWP. The RAP/PCWP tertiles were 0.27 to 0.4 (tertile 1); 0.41 to 0.615 (tertile 2), and 0.62 to 1.21 (tertile 3). Increasing RAP/PCWP was associated with increasing median right atrial area (23, 26, 29 cm 2 , respectively; P <0.005), RV area in diastole (21, 27, 27 cm 2 , respectively; P <0.005), and pulmonary vascular resistance (2.4, 2.9, 3.6 woods units, respectively; P =0.003), and lower RV stroke work index (8.6, 8.4, 5.5 g·m/m 2 per beat, respectively; P <0.001). RAP/PCWP ratio was associated with death or hospitalization within 6 months (hazard ratio, 1.16 [1, 1.4]; P <0.05).

Conclusions—

Increased RAP/PCWP ratio was associated with higher pulmonary vascular resistance, reduced RV function (manifest as a larger right atrium and ventricle and lower RV stroke work index), and an increased risk of adverse outcomes in patients with advanced heart failure.

Mechanisms of bleeding and approach to patients with axial-flow left ventricular assist devices

Axial-flow LVADs have become an integral tool in the management of end-stage heart failure. Consequently, nonsurgical bleeding has emerged as a major source of morbidity and mortality in this fragile population. The mechanisms responsible for these adverse events include acquired von Willebrand disease, GI tract angiodysplasia formation, impaired platelet aggregation, and overuse of anticoagulation therapy. Because of ongoing concerns for pump thrombosis and thromboembolic events, the thrombotic/bleeding paradigm has led to a difficult clinical dilemma for those managing patients treated with axial flow LVADs. As the field progresses, advances in the understanding of the pathological mechanisms underlying bleeding/thrombosis risk, careful risk stratification, and potential use of novel anticoagulants will all play a role in the management of the LVAD patient.

Contamination of potable water by enterotoxigenic Escherichia coli: qPCR based culture-free detection and quantification

Tourists visiting to endemic zones may acquire Enterotoxigenic Escherichia coli (ETEC) infection resulting into diarrhea due to consumption of contaminated potable waters. In this study, a qPCR assay (SYBR Green), targeting LT1 and ST1 genes was designed to quantify ETEC in potable waters derived from civic water supply. The assay could detect lowest 1CFU/PCR targeting LT1/ST1 gene from ten-fold diluted culture of the reference strain (E. coli MTCC 723) and is ten-fold more sensitive than the conventional PCR. The quantification of the ETEC in potable waters collected from civic supply of a major city of the northern India exhibiting high flow of tourists reveals that all the sites that ran along sewage line were contaminated by the ETEC. Contamination was due to percolation of sewage. The assay could be used for the regular monitoring of potable water in places exhibiting heavy flow of tourists to prevent ETEC induced diarrhea.

Durable mechanical circulatory support devices

Individuals afflicted with advanced systolic heart failure who have become unresponsive to standard medical and electrical therapies are categorized as having American Heart Association stage D heart failure. The high mortality rates for medically treated stage D heart failure have not improved in the last 10 years, and patients at this advanced stage require either palliative measures or surgical management of heart failure. In recent years, surgically implanted ventricular assist devices (VADs) have become available for long-term use and are now commonly used as a therapy for advanced heart failure. The data generated from this early experience have clearly shown that VADs improve survival and quality of life in patients with advanced heart failure when implanted as a temporary measure or as long-term support. However, with a growing heart failure population, there is much work to be done to continually improve VAD technology, patient selection criteria, and postimplantation management to define the optimal role for assist devices in the management of systolic heart failure.

Xenon exposure in the neonatal rat brain: effects on genes that regulate apoptosis

BACKGROUND

In the developing rodent brain, exposure to volatile anesthetics causes widespread neuronal apoptosis in several regions of the brain. Increasing evidence points to a possible neuroprotective role for the anesthetic gas xenon, following neuronal injury. To address this gap in understanding, we explored the transcriptional consequences of xenon in the brains of postnatal day 7 (P7) rats exposed to xenon compared to those of air-breathing animals, with particular emphasis on the mRNA transcript levels of Akt and c-Jun N-terminal kinase kinase 1 (JNKK1), which are important for cell survival and the activation of extrinsic neuroapoptotic pathways, respectively.

METHODS

P7 Sprague/Dawley rats were exposed to air (75% nitrogen, 25% oxygen) or xenon (75% xenon, 25% oxygen) for 120 min (N=6/group). Forebrains were harvested for reverse transcription polymerase chain reaction, which enabled quantification of Akt and JNKK1 mRNA transcripts. Suppression subtractive hybridization was used to explore the "genetic signature" of xenon exposure.

RESULTS

Compared to control air-breathing animals, xenon-breathing rats exhibited a 0.7-fold decrease in Akt mRNA expression (P<0.01) and a 1.6-fold increase in JNKK1 mRNA levels (P<0.05).

CONCLUSION

The concomitant decrease in the Akt mRNA expression level and increase in the JNKK1 mRNA transcript level provide evidence that xenon has a neuroapoptotic effect in the developing rodent forebrain. Given these results, further study into the paradoxical neuroprotective and neuroapoptotic effects of xenon is warranted.

Functional selectivity in adrenergic and angiotensin signaling systems

β-Adrenergic and angiotensin II type 1A receptors are therapeutic targets for the treatment of a number of common human diseases. Pharmacological agents designed as antagonists for these receptors have positively affected the morbidity and mortality of patients with hypertension, heart failure, and renal disease. Antagonism of these receptors, however, may only partially explain the therapeutic benefits of β-blockers and angiotensin receptor blockers given the emerging concept of functional selectivity or biased agonism. This new pharmacological paradigm suggests that multiple signaling pathways can be differentially modified by a single ligand-receptor interaction. This review examines the functional selectivity of β-adrenergic and angiotensin II type 1A receptors with respect to their ability to signal via both G protein-dependent and G protein-independent mechanisms, with a focus on the multifunctional protein β-arrestin. Also highlighted are the concept of "biased signaling" through β-arrestin mediated pathways, the affect of ligand/receptor modification on such biased agonism, and the implications of functional selectivity for the development of the next generation of β-blockers and angiotensin receptor blockers.

Thiazolidinediones and risk for atherosclerosis: pleiotropic effects of PPar gamma agonism

Despite advances in the development of anti-hyperglycaemic drugs and a greater focus on cardiovascular risk modification for patients with diabetes, cardiovascular disease remains the most common complication of type 2 diabetes. Since their initial availability in 1997, the thiazolidinediones have become one of the most commonly prescribed classes of medications for type 2 diabetes. In addition to glucose control, the thiazolidinediones have a number of pleiotropic effects on myriad traditional and non-traditional risk factors for cardiovascular disease, and hold promise with regard to modification of cardiovascular risk. In a recently reported large-scale clinical trial, pioglitazone was associated with improved cardiovascular outcomes in patients with type 2 diabetes and prevalent atherosclerotic disease. In this review, we summarise the experimental, preclinical and clinical data regarding the effects of the thiazolidinediones on cardiovascular risk factors and clinical outcomes.

Lung transplantation for primary and secondary pulmonary hypertension

BACKGROUND

Single lung transplantation (SLT) and bilateral lung transplantation (BLT) are routinely performed in patients with primary pulmonary hypertension (PPH) and secondary pulmonary hypertension (SPH). It is unclear which procedure is preferable. We reviewed our experience with lung transplants for PPH and SPH to determine if any advantage exists with SLT or BLT for either PPH or SPH.

METHODS

We reviewed the outcomes of all lung transplants performed for PPH or SPH for 4.5 years (July 1995 to January 2000). Survival was reported by the Kaplan-Meier method, and log rank analysis was used to determine significance. Statistical analyses of clinical data were performed using analysis of variance and chi2 analysis.

RESULTS

A total of 57 recipients met criteria for pulmonary hypertension with a mean pulmonary artery pressure of greater than or equal to 30 mm Hg. There were 15 patients with PPH and 40 patients with SPH. There were 6 patients who had SLTs and 9 patients who had BLTs in the PPH group; and there were 9 patients who had SLTs and 21 patients who had BLTs in the SPH group. We found a survival advantage for PPH patients who underwent BLTs at all time points up to 4 years (100% vs 67%; p < or = 0.02). There was no clear advantage to SLTs or BLTs for SPH. At 4 years there was a trend toward improved survival with SLTs (91% vs 75%) in SPH patients with a mean pulmonary artery pressure less than or equal to 40 mm Hg (p < or = 0.11) with equivalent survival (80%) in patients with a mean pulmonary artery pressure greater than or equal to 40 mm Hg. There was also a trend toward improved survival in patients with a mean pulmonary artery pressure greater than or equal to 40 mm Hg (PPH and SPH) with BLTs (88% vs 62%; p = 0.19). The incidence of rejection, infection, and other complications was comparable between SLTs and BLTs in each group.

CONCLUSIONS

We believe that BLT is the procedure of choice for PPH. The procedure of choice is less clear for SPH. Patients with SPH and a mean pulmonary artery pressure greater than 40 mm Hg may benefit from a BLT and those with a mean pulmonary artery pressure less than or equal to 40 mm Hg may do better with an SLT; however, no clear advantage is seen.

Wilms' tumor suppressor gene (WT1) is expressed in primary breast tumors despite tumor-specific promoter methylation

We analyzed Wilms' tumor suppressor 1 (WT1) expression and its regulation by promoter methylation in a panel of normal breast epithelial samples and primary carcinomas. Contrary to previous reports, WT1 protein was strongly expressed in primary carcinomas (27 of 31 tumors) but not in normal breast epithelium (1 of 20 samples). Additionally, the WT1 promoter was methylated in 6 of 19 (32%) primary tumors, which nevertheless expressed WT1. The promoter is not methylated in normal epithelium. Thus, although tumor-specific methylation of WT1 is established in primary breast cancer at a low frequency, other transcriptional regulatory mechanisms appear to supercede its effects in these tumors. Our results demonstrate expression of WT1 in mammary neoplasia, and that WT1 may not have a tumor suppressor role in breast cancer.

Analysis of the humoral response to the flagellin protein of Borrelia burgdorferi: cloning of regions capable of differentiating Lyme disease from syphilis

Selected regions of the Borrelia burgdorferi flagellin gene (fla) that exhibit high or low homology with related genes from other bacterial species were amplified by the polymerase chain reaction and expressed as fusion proteins in Escherichia coli. Purified fusion proteins were assayed for antibody reactivity in a microtiter plate enzyme-linked immunosorbent assay with sera from Lyme disease patients as well as syphilitic and normal sera. Immunoglobulin G antibody from Lyme disease patient sera reacted predominantly with the central portion of the protein. The region of the flagellin protein encompassing amino acids 64 to 311 detected nearly all of the immunoglobulin G-positive Lyme sera and only reacted with 1 of 26 syphilis patient serum samples. In contrast, 12 of 26 syphilis patient serum samples and 2 of 47 normal serum samples reacted with the amino terminus of the flagellin protein, whereas 4 of 26 syphilis patient serum samples and 7 of 47 normal serum samples reacted with the carboxyl terminus. The central region containing amino acids 64 to 311 may be employed diagnostically to differentiate antibodies to B. burgdorferi from antibodies to Treponema pallidum. In addition, this region also was recognized by immunoglobulin M in the Lyme patient sera, indicating its potential usefulness as a marker for early Lyme disease.

Cardiopulmonary effects of Intralipid infusion in critically ill patients

Cardiopulmonary effects of 500 ml of 20% iv fat emulsion (Intralipid) infusion in two groups of patients who required mechanical ventilation were evaluated in our Critical Care Center. Group 1 included ten patients void of signs or symptoms of sepsis. Group 2 consisted of ten patients exhibiting clinical and laboratory signs and symptoms of sepsis. Data were measured before and immediately after Intralipid infusion and when serum lipemia cleared. Intralipid infusion precipitated a significant increase in venous admixture (Qsp/Qt) from 13.7 +/- 3.6 (SEM) to 18.0 +/- 6.5% and from 22.0 +/- 4.8 to 25.8 +/- 7.0% in groups 1 and 2, respectively. Mean pulmonary artery pressure (MPAP) increased from 22.7 +/- 4.2 to 29.2 +/- 8.1 mm Hg and 26.4 +/- 6.8 to 28.0 +/- 4.0 mm Hg in groups 1 and 2, respectively. When serum lipemia cleared, Qsp/Qt and MPAP returned to preinfusion levels. We conclude that Intralipid infusion increases pulmonary artery pressure and venous admixture in critically ill patients. These changes are temporary and coincidental with serum lipemia rather than presence or absence of sepsis. Adequate levels of oxygenation should be confirmed during Intralipid infusion in patients with borderline oxygenation.