Transcriptomic Analysis Identifies the Effect of Beta-Blocking Agents on a Molecular Pathway of Contraction in the Heart and Predicts Response to Therapy.

Over the last decades, beta-blockers have been a key component of heart failure therapy. However, currently there is no method to identify patients who will benefit from beta-blocking therapy versus those who will be unresponsive or worsen. Furthermore, there is an unmet need to better understand molecular mechanisms through which heart failure therapies, such as beta-blockers, improve cardiac function, in order to design novel targeted therapies. Solving these issues is an important step towards personalized medicine. Here, we present a comprehensive transcriptomic analysis of molecular pathways that are affected by beta-blocking agents and a transcriptomic biomarker to predict therapy response.

The variable natural history of idiopathic dilated cardiomyopathy.

BACKGROUND: Determining the prognosis of patients with heart failure is essential for patient management and clinical trial conduct. The relative value of traditional prognostic criteria remains unclear and the assessment of long-term prognosis for individual patients is problematic. OBJECTIVES: To determine the ability of clinical, hemodynamic and echocardiographic parameters to predict the long-term prognosis of patients with idiopathic dilated cardiomyopathy. METHODS: We investigated the ability of clinical, hemodynamic and echocardiographic parameters to predict the long-term prognosis of individual patients in a large, representative, contemporary cohort of idiopathic dilated cardiomyopathy (IDCM) patients referred to Johns Hopkins from 1997 to 2004 for evaluation of cardiomyopathy. In all patients a baseline history was taken, and physical examination, laboratory studies, echocardiogram, right heart catheterization and endomyocardial biopsy were performed. RESULTS: In 171 IDCM patients followed for a median 3.5 years, there were 50 long-term event-free survivors (LTS) (median survival 6.4 years) and 34 patients died or underwent ventricular assist device placement or transplantation within 5 years (NLTS; non-long-term survivors) (median time to event 1.83 years. Established risk factors (gender, race, presence of diabetes, serum creatinine, sodium) and the use of accepted heart failure medications (angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, beta blockers) were similar between the two groups. Although LTS had younger age, higher ejection fraction (EF) and lower New York Heart Association (NYHA) class at presentation, the positive predictive value of an EF < 25% was 64% (95% CI 41%-79%) and that of NYHA class > 2 was 53% (95% CI 36-69%). A logistic model incorporating these three variables incorrectly classified 29% of patients. CONCLUSIONS: IDCM exhibits a highly variable natural history and standard clinical predictors have limited ability to classify IDCM patients into broad prognostic categories. These findings suggest that there are important host-environmental factors still unappreciated in the biology of IDCM.

Transcriptomic biomarkers for the accurate diagnosis of myocarditis.

BACKGROUND: Lymphocytic myocarditis is a clinically important condition that is difficult to diagnose and distinguish. We hypothesized that the transcriptome obtained from an endomyocardial biopsy would yield clinically relevant and accurate molecular signatures. METHODS AND RESULTS: Microarray analysis was performed on samples from patients with histologically proven lymphocytic myocarditis (n=16) and idiopathic dilated cardiomyopathy (n=32) to develop accurate diagnostic transcriptome-based biomarkers using multiple classification algorithms. We identified 9878 differentially expressed genes in lymphocytic myocarditis versus idiopathic dilated cardiomyopathy (fold change >1.2; false discovery rate <5%) from which a transcriptome-based biomarker containing 62 genes was identified that distinguished myocarditis with 100% sensitivity (95% confidence interval, 46 to 100) and 100% specificity (95% confidence interval, 66 to 100) and was generalizable to a broad range of secondary cardiomyopathies associated with inflammation (n=27), ischemic cardiomyopathy (n=8), and the normal heart (n=11). Multiple classification algorithms and quantitative real-time reverse-transcription polymerase chain reaction analysis further reduced this subset to a highly robust molecular signature of 13 genes, which still performed with 100% accuracy. CONCLUSIONS: Together, these findings demonstrate that transcriptomic biomarkers from a single endomyocardial biopsy can improve the clinical detection of patients with inflammatory diseases of the heart. This approach advances the clinical management and treatment of cardiac disorders with highly variable outcome.

Myocardial parvovirus B19 persistence: lack of association with clinicopathologic phenotype in adults with heart failure.

BACKGROUND: Multiple viruses have been isolated from the heart, but their significance remains controversial. We sought to determine the prevalence of cardiotropic viruses in endomyocardial biopsy (EMB) samples from adult patients with heart failure (HF) and to define the clinicopathologic profile of patients exhibiting viral positivity. METHODS AND RESULTS: EMB from 100 patients (median ejection fraction, 30%; interquartile range [IQR], 20% to 45%) presenting for cardiomyopathy evaluation (median symptom duration, 5 months; IQR, 1 to 13 months) were analyzed by polymerase chain reaction for adenovirus, cytomegalovirus, enteroviruses, Epstein-Barr virus, and parvovirus B19. Each isolate was sequenced, and viral load was determined. Parvovirus B19 was the only virus detected in EMB samples (12% of subjects). No patient had antiparvovirus IgM antibodies, but all had IgG antibodies, suggesting viral persistence. The clinical presentation of parvovirus-positive patients was markedly heterogeneous with both acute and chronic HF, variable ventricular function, and ischemic cardiomyopathy. No patient met Dallas histopathologic criteria for active or borderline myocarditis. Two patients with a positive cardiac MRI and presumed "parvomyocarditis" had similar viral loads to autopsy controls without heart disease. The oldest parvovirus-positive patients were positive for genotype 2, suggesting lifelong persistence in the myocardium. CONCLUSIONS: Parvovirus B19 was the only virus isolated from EMB samples in this series of adult patients with HF from the United States. Positivity was associated with a wide array of clinical presentations and HF phenotypes. Our studies do not support a causative role for parvovirus B19 persistence in HF and, therefore, advocate against the use of antiviral therapy for these patients.

The gene expression profile of patients with new-onset heart failure reveals important gender-specific differences.

AIMS: We sought to test the hypothesis that inherent biological factors contribute to gender differences in disease pathophysiology of new-onset heart failure (HF), which can be detected from the transcriptome of a single endomyocardial biopsy (EMB). METHODS AND RESULTS: We analysed samples from male (n = 29) and female patients (n = 14) with idiopathic dilated cardiomyopathy (IDCM) and new-onset HF with U133 Plus 2.0 microarrays (Affymetrix) and significance analysis of microarrays (SAM). There were 35 overexpressed and 16 downregulated transcripts in men vs. women [q < 5%, fold change (FC) > 1.2]. In addition to overexpression of Y-chromosome-related transcripts (n = 18), such as USP9Y (FC > 13.1), DDX3Y (FC > 11.3), RPS4Y1 (FC > 9.9), and EIF1AY (FC > 11.8) in males, there was overexpression of CD24 (FC > 5.6) and KCNK1 (FC > 1.5). In females, XIST was highly overexpressed (FC > 28.9), together with X-linked zinc finger proteins (FC > 1.9) and autosomal genes GATAD1 (FC > 1.6), SLC2A12 (FC > 2.9), and PDE6B (FC > 1.5). Analysis of a public data set of end-stage IDCM (n = 15) resulted in approximately 85% overlap with our findings. CONCLUSION: This is the first study that identified gender-specific transcriptomic differences in new-onset HF. Our findings may offer novel insights into fundamental biological differences in the pathophysiology of HF between sexes and provide a platform for personalized medicine.

Thresholds of physical activity and life expectancy for patients considering destination ventricular assist devices.

BACKGROUND: Current implantable left ventricular assist devices (LVAD) improve survival and function for patients with very late stage heart failure (HF) but may also offer benefit before inotrope dependence. Debate continues about selection of HF patients for LVAD therapy. We sought to determine what level of personal risk and disability HF patients thought would warrant LVAD therapy. METHODS: The study included 105 patients with symptomatic HF and an LV ejection fraction (EF) < 35% who were given a written paragraph about LVADs and asked about circumstances under which they would consider such a device. New York Heart Association (NYHA) functional class, time trade-off utility, and patient-assessed functional score were determined. RESULTS: Participants (mean age, 58 years) had an LVEF of 21%. The median duration of HF was 5 years, and 65% had a primary prevention implantable cardioverter defibrillator. Presented with a scenario of bed-ridden HF, 81% stated they would definitely or probably want an LVAD; 50% would consider LVAD to prolong survival if HF survival were predicted to be < 1 year and 75% if < 6 months. Meanwhile, 44% would consider LVAD if they could only walk < 1 block and 64% if they could not dress without stopping. Anticipated thresholds did not differ by NYHA class, time trade-off, or functional score. CONCLUSIONS: Patient thresholds for LVAD insertion parallel objective survival and functional data. HF patients would be receptive to referral for discussion of LVAD by the time expected mortality is within 6 to 12 months and activity remains limited to less than 1 block.

Paragangliomas: etiology, presentation, and management.

Paragangliomas are catecholamine-secreting tumors arising from the chromaffin cells of the sympathetic ganglia, and are known as extra-adrenal pheochromocytomas. These tumors commonly present with episodic hypertension, tachycardia, headache, and diaphoresis, and can be either benign or malignant. Diagnosis is made by serum and urine analysis for catecholamines and metanephrines, and confirmed with imaging studies including computed tomography scanning, magnetic resonance imaging, or 123-I metaiodobenzylguanidine imaging. Although the majority of paragangliomas are sporadic, a growing percentage of cases are found to be part of a familial genetic syndrome. Genetic testing should be offered to patients diagnosed with paraganglioma, particularly in patients who are young, have multiple tumors, or have a family history of malignancy. Management of paraganglioma is predicated on surgical resection, and careful perioperative management with alpha- and beta-adrenergic blockade is imperative for optimal outcomes. The majority of these tumors are benign, but for patients with malignant disease, chemotherapy, and radiation therapy may provide modest benefit. Long-term follow-up is essential, as paragangliomas can recur many years after initial diagnosis. Ongoing research into the genetic underpinnings of this tumor may allow for more targeted molecular therapies in the future.

Transcriptomic biomarkers for individual risk assessment in new-onset heart failure.

BACKGROUND: Prediction of prognosis remains a major unmet need in new-onset heart failure (HF). Although several clinical tests are in use, none accurately distinguish between patients with poor versus excellent survival. We hypothesized that a transcriptomic signature, generated from a single endomyocardial biopsy, could serve as a novel prognostic biomarker in HF. METHODS AND RESULTS: Endomyocardial biopsy samples and clinical data were collected from all patients presenting with new-onset HF from 1997 to 2006. Among a total of 350 endomyocardial biopsy samples, 180 were identified as idiopathic dilated cardiomyopathy. Patients with phenotypic extremes in survival were selected: good prognosis (event-free survival for at least 5 years; n=25) and poor prognosis (events [death, requirement for left ventricular assist device, or cardiac transplant] within the first 2 years of presentation with HF symptoms; n=18). We used human U133 Plus 2.0 microarrays (Affymetrix) and analyzed the data with significance analysis of microarrays and prediction analysis of microarrays. We identified 46 overexpressed genes in patients with good versus poor prognosis, of which 45 genes were selected by prediction analysis of microarrays for prediction of prognosis in a train set (n=29) with subsequent validation in test sets (n=14 each). The biomarker performed with 74% sensitivity (95% CI 69% to 79%) and 90% specificity (95% CI 87% to 93%) after 50 random partitions. CONCLUSIONS: These findings suggest the potential of transcriptomic biomarkers to predict prognosis in patients with new-onset HF from a single endomyocardial biopsy sample. In addition, our findings offer potential novel therapeutic targets for HF and cardiomyopathy.

The association between high-dose diuretics and clinical stability in ambulatory chronic heart failure patients.

OBJECTIVE: In chronic heart failure (HF), diuretic doses increase as the disease progresses, often after hospitalization for instability, and have been associated with worsening renal function and increased mortality. METHODS AND RESULTS: A prospective observational analysis of 183 patients in an advanced HF clinic stratified at baseline by diuretic dose (low dose < or = 80 mg, high dose > 80 mg furosemide equivalent) was performed. All patients were followed for 1 year, and the primary outcome was a combined HF event of admission for HF, cardiac transplant, mechanical cardiac support, or death. Compared with patients taking low-dose diuretics (n = 113), patients taking high-dose diuretics (n = 70) had more markers of increased cardiovascular risk and were more likely to have a history of recent instability (33% vs 4.4% in low dose, P < .001). High doses of diuretics were a strong univariate predictor of subsequent HF events (hazard ratio 3.83, 95% confidence interval 1.82-8.54); however, after adjustment for clinical stability, diuretic dose no longer remained significant (hazard ratio 1.53, 95% confidence interval 0.58-4.03). CONCLUSION: High-dose diuretics may be more of a marker than a cause of instability. A history of HF stability during the past 6 months is associated with an 80% lower risk of an HF event during the next year, independently of baseline diuretic dose.

Right ventricular dysfunction and adverse outcome in patients with advanced heart failure.

BACKGROUND: In patients with heart failure (HF) from left ventricular systolic dysfunction, the presence of coexistent right ventricular (RV) dysfunction is associated with poor exercise capacity and reduced survival. We sought to determine whether a simple measure of RV function, the RV myocardial performance index (RV MPI), is associated with adverse outcome in a population of advanced heart failure patients selected to receive cardiac resynchronization therapy (CRT). METHODS AND RESULTS: The RV MPI was measured on 77 consecutive preimplantation echocardiograms. The relationship between RV MPI and the end point of all-cause mortality, transplantation, or ventricular assist device placement was evaluated. The end point occurred in 28 patients (36%) during a median follow-up of 21 months. The median RV MPI was 0.73 (interquartile range 0.51-0.89). Worse RV function, as demonstrated by a higher RV MPI, was seen in those patients who reached the end point compared with those who did not (0.83 vs. 0.69, P = .004). The highest tercile of RV MPI was associated with a 3.3-fold increased risk of poor outcome (95% CI 1.3-8.5). Each 0.1 unit increase in RV MPI was associated with a 16% increased risk (95% CI 8-26). After adjusting for other echocardiographic variables, RV MPI remained significantly associated with the outcome. CONCLUSION: In a population of advanced HF patients selected to receive CRT, RV dysfunction, as assessed by the RV MPI, is associated with adverse outcome. Wider use of this simple nongeometric parameter may help to identify patients for whom options for further intervention should be carefully evaluated.

Relation of right ventricular peak systolic pressure to major adverse events in patients undergoing cardiac resynchronization therapy.

The degree to which increased right-sided heart pressures influence outcome in cardiac resynchronization therapy (CRT) is unclear. High right ventricular (RV) pressures may contribute to septal malpositioning, thus hindering effective resynchronization. We hypothesized that patients with high RV systolic pressures before CRT implantation would have poorer outcome. We evaluated echocardiograms, electrocardiograms, and clinical records from 75 consecutive patients with CRT. RV systolic pressure was calculated from the peak tricuspid regurgitant, time-velocity profile. The primary end point was a composite of mortality, cardiac transplantation, or need for a left ventricular assist device. Events were evaluated by Kaplan-Meier curves and Cox proportional hazard ratios. Patients grouped by RV systolic pressure divided at the median of 35 mm Hg were similar except for more renal insufficiency and RV dysfunction when RV systolic pressure was >35 mm Hg. Univariate analysis identified RV systolic pressure >35 mm Hg (hazard ratio [HR] 3.32), diabetes (HR 2.45), renal insufficiency (HR 3.52), atrial fibrillation (HR 3.07), use of nonamiodarone antiarrhythmic medications (HR 2.86), atrial pacing (HR 2.57), and prolonged PR interval (HR 1.009) as associated with poorer outcome. Normal sinus rhythm at implantation (HR 0.34), baseline left bundle branch block (HR 0.44), and beta-blocker use (HR 0.47) were associated with improved outcome. In a multivariable model, high RV systolic pressure (HR 3.71, 95% confidence interval 1.31 to 10.4), renal insufficiency (HR 3.18, 95% confidence interval 1.29 to 7.86), and atrial fibrillation (HR 4.22, 95% confidence interval 1.54 to 11.6) remained significant. In conclusion, despite resynchronization, patients with high RV pressures have significantly decreased survival after adjusting for significant contributing influences.

Immune modulation therapy in heart failure.

Several lines of evidence suggest that inflammation plays a pathogenic role in the development and progression of congestive heart failure, influencing heart contractility and hypertrophy, promoting apoptosis, and contributing to the myocardial remodeling process. As the prevalence of heart failure continues to increase, novel therapeutic strategies are employed to decrease the burden of this disease. Although multiple studies have suggested a potential for immunomodulatory therapy in heart failure patients, the precise role of this targeted approach still remains to be determined. Further research is needed to identify the key factors in the immunopathogenesis of heart failure, identify the patients who are most likely to respond, and develop management strategies that result in consistent benefit leading to decreased morbidity and mortality in the heart failure patient population.

Characteristics of patients who die with heart failure and a low ejection fraction in the new millennium.

BACKGROUND: Therapies for heart failure (HF) with a low ejection fraction (EF) have delayed disease progression and prolonged survival, but the implications of these therapies on the end stages of HF have not been examined. METHODS AND RESULTS: Patients seen by the Brigham and Women's cardiomyopathy service with an EF < or =35%, at least 1 outpatient visit or at least 30 days of follow-up who died between January 1, 2000, and October 20, 2003, were evaluated retrospectively. Of the 160 patients who died since 2000, 80 (50%) were outpatients. In the 6 months before death, 93% of patients had New York Heart Association (NYHA) class III or IV symptoms. The NYHA class, clinical characteristics, medications, and comorbidities differed little between inpatient and outpatient deaths. Renal insufficiency and hyponatremia were worse in the months preceding death than at the time of death (creatinine: 3.2 versus 2.3 mg/dL, P < .0001; sodium: 128 versus 135 mmol/L, P < .0001, respectively). Death was considered sudden in only 21% of patients. CONCLUSION: Deaths in the current era of HF management occur in patients with long-standing HF characterized by biventricular dysfunction and advanced symptoms. Most deaths are heralded by hyponatremia, acute on chronic renal insufficiency, and frequent hospitalizations.