Endothelial nitric oxide synthase (NOS3) polymorphisms in African Americans with heart failure: results from the A-HeFT trial

Diversity in modern heart failure trials: Where are we, and where are we going

Over the last three decades, increased attention has been given to the representation of historically underrepresented groups within the landscape of pivotal clinical trials. However, recent events (i.e., coronavirus pandemic) have laid bare the potential continuation of historic inequities in available clinical trials and studies aimed at the care of broad patient populations. Anecdotally, cardiovascular disease (CVD) has not been immune to these disparities. Within this review, we examine and discuss recent landmark CVD trials, with a specific focus on the representation of Blacks within several critically foundational heart failure clinical trials tied to contemporary treatment strategies and drug approvals. We also discuss solutions for inequities within the landscape of cardiovascular trials. Building a more diverse clinical trial workforce coupled with intentional efforts to increase clinical trial diversity will advance equity in cardiovascular care.

Pharmacogenetics to guide cardiovascular drug therapy

Over the past decade, pharmacogenetic testing has emerged in clinical practice to guide selected cardiovascular therapies. The most common implementation in practice is CYP2C19 genotyping to predict clopidogrel response and assist in selecting antiplatelet therapy after percutaneous coronary intervention. Additional examples include genotyping to guide warfarin dosing and statin prescribing. Increasing evidence exists on outcomes with genotype-guided cardiovascular therapies from multiple randomized controlled trials and observational studies. Pharmacogenetic evidence is accumulating for additional cardiovascular medications. However, data for many of these medications are not yet sufficient to support the use of genotyping for drug prescribing. Ultimately, pharmacogenetics might provide a means to individualize drug regimens for complex diseases such as heart failure, in which the treatment armamentarium includes a growing list of medications shown to reduce morbidity and mortality. However, sophisticated analytical approaches are likely to be necessary to dissect the genetic underpinnings of responses to drug combinations. In this Review, we examine the evidence supporting pharmacogenetic testing in cardiovascular medicine, including that available from several clinical trials. In addition, we describe guidelines that support the use of cardiovascular pharmacogenetics, provide examples of clinical implementation of genotype-guided cardiovascular therapies and discuss opportunities for future growth of the field.

Race and genetics versus 'race' in genetics: A systematic review of the use of African ancestry in genetic studies

Social scientists have long understood race to be a social category invented to justify slavery and evolutionary biologists know the socially constructed racial categories do not align with our biological understanding of genetic variation. The completion of the Human Genome Project in 2003 confirmed humans are 99.9% identical at the DNA level and there is no genetic basis for race. A systematic review of the PubMed medical literature published since 2003 was conducted to assess the use of African ancestry to denote study populations in genetic studies categorized as clinical trials, to examine the stated rationale for its use and to assess the use of evolutionary principles to explain human genetic diversity. We searched for papers that included the terms 'African', 'African American' or 'Black' in studies of behavior (20 papers), physiological responses, the pharmacokinetics of drugs and/or disease associations (62 papers), and as a genetic category in studies, including the examination of genotypes associated with life stress, pain, stuttering and drug clearance (126 papers). Of these, we identified 74 studies in which self-reported race alone or in combination with admixture mapping was used to define the study population. However, none of these studies provided a genetic explanation for the use of the self-identified race as a genetic category and only seven proffered evolutionary explanations of their data. The concept of continuous genetic variation was not clearly articulated in any of these papers, presumably due to the paucity of evolutionary science in the college and medical school curricula.

When the At-Risk Do Not Develop Heart Failure: Understanding Positive Deviance Among Postmenopausal African American and Hispanic Women

BACKGROUND

African American and Hispanic postmenopausal women have the highest risk for heart failure compared with other races, but heart failure prevalence is lower than expected in some national cohorts. It is unknown whether psychosocial factors are associated with lower risk of incident heart failure hospitalization among high-risk postmenopausal minority women.

METHODS AND RESULTS

Using the Women's Health Initiative Study, African American and US Hispanic women were classified as high-risk for incident heart failure hospitalization with 1 or more traditional heart failure risk factors and the highest tertile heart failure genetic risk scores. Positive psychosocial factors (optimism, social support, religion) and negative psychosocial factors (living alone, social strain, depressive symptoms) were measured using validated survey instruments at baseline. Adjusted subdistribution hazard ratios of developing heart failure hospitalization were determined with death as a competing risk. Positive deviance indicated not developing incident heart failure hospitalization with 1 or more risk factors and the highest tertile for genetic risk. Among 7986 African American women (mean follow-up of 16 years), 27.0% demonstrated positive deviance. Among high-risk African American women, optimism was associated with modestly reduced risk of heart failure hospitalization (subdistribution hazard ratio 0.94, 95% confidence interval 0.91-0.99), and social strain was associated with modestly increased risk of heart failure hospitalization (subdistribution hazard ratio 1.07, 95% confidence interval 1.02-1.12) in the initial models; however, no psychosocial factors were associated with heart failure hospitalization in fully adjusted analyses. Among 3341 Hispanic women, 25.1% demonstrated positive deviance. Among high-risk Hispanic women, living alone was associated with increased risk of heart failure hospitalization (subdistribution hazard ratio 1.97, 95% confidence interval 1.06-3.63) in unadjusted analyses; however, no psychosocial factors were associated with heart failure hospitalization in fully adjusted analyses.

CONCLUSIONS

Among postmenopausal African American and Hispanic women, a significant proportion remained free from heart failure hospitalization despite having the highest genetic risk profile and 1 or more traditional risk factors. No observed psychosocial factors were associated with incident heart failure hospitalization in high-risk African Americans and Hispanics. Additional investigation is needed to understand protective factors among high-risk African American and Hispanic women.

Understanding the Complexity of Heart Failure Risk and Treatment in Black Patients

Although care of patients with heart failure (HF) has improved in the past decade, important disparities in HF outcomes persist based on race/ethnicity. Age-adjusted HF-related cardiovascular disease death rates are higher for Black patients, particularly among young Black men and women whose rates of death are 2.6- and 2.97-fold higher, respectively, than White men and women. Similarly, the rate of HF hospitalization for Black men and women is nearly 2.5-fold higher when compared with Whites, with costs that are significantly higher in the first year after HF hospitalization. While the relative rate of HF hospitalization has improved for other race/ethnic minorities, the disparity in HF hospitalization between Black and White patients has not decreased during the last decade. Although access to care and socioeconomic status have been traditional explanations for the observed racial disparities in HF outcomes, contemporary data suggest that novel factors including genetic susceptibility as well as social determinants of health and implicit bias may play a larger role in health outcomes than previously appreciated. The purpose of this review is to describe the complex interplay of factors that influence racial disparities in HF incidence, prevalence, and disease severity, with a highlight on evolving knowledge that will impact the clinical care and address future research needs to improve HF disparities in Blacks.

Ser49Gly Beta1-Adrenergic Receptor Genetic Polymorphism as a Death Predictor in Brazilian Patients with Heart Failure

Background The role of Ser49Gly beta1-adrenergic receptor genetic polymorphism (ADBR1-GP-Ser49Gly) as a predictor of death in heart failure (HF) is not established for the Brazilian population. Objectives To evaluate the association between ADBR1-GP-Ser49Gly and clinical outcomes in individuals with HF with reduced ejection fraction. Methods Secondary analysis of medical records of 178 patients and genotypes of GPRβ1-Ser49Gly variants, classified as Ser-Ser, Ser-Gly and Gly-Gly. To evaluate their association with clinical outcome. A significance level of 5% was adopted. Results Cohort means were: clinical follow-up 6.7 years, age 63.5 years, 64.6% of men and 55.1% of whites. HF etiologies were predominantly ischemic (31.5%), idiopathic (23.6%) and hypertensive (15.7%). The genetic profile was distributed as follows: 122 Ser-Ser (68.5%), 52 Ser-Gly (28.7%) and 5 Gly-Gly (2.8%). There was a significant association between these genotypes and mean NYHA functional class at the end of follow-up (p = 0.014) with Gly-Gly being associated with less advanced NYHA. In relation to the clinical outcomes, there was a significant association (p = 0.026) between mortality and GPRβ1-Ser49Gly: the number of deaths in patients with Ser-Gly (12) or Gly-Gly (1) was lower than in those with Ser-Ser (54). The Gly allele had an independent protective effect maintained after multivariate analysis and was associated with a reduction of 63% in the risk of death (p = 0.03; Odds Ratio 0.37 - CI 0.15-0.91). Conclusion The presence of β1-AR-GP Gly-Gly was associated with better clinical outcome evaluated by NYHA functional class and was a predictor of lower risk of mortality, regardless of other factors, in a 6.7-year of follow-up. (Arq Bras Cardiol. 2020; 114(4):613-615).

Addressing Social Determinants of Health in the Care of Patients With Heart Failure: A Scientific Statement From the American Heart Association

Heart failure is a clinical syndrome that affects >6.5 million Americans, with an estimated 550 000 new cases diagnosed each year. The complexity of heart failure management is compounded by the number of patients who experience adverse downstream effects of the social determinants of health (SDOH). These patients are less able to access care and more likely to experience poor heart failure outcomes over time. Many patients face additional challenges associated with the cost of complex, chronic illness management and must make difficult decisions about their own health, particularly when the costs of medications and healthcare appointments are at odds with basic food and housing needs. This scientific statement summarizes the SDOH and the current state of knowledge important to understanding their impact on patients with heart failure. Specifically, this document includes a definition of SDOH, provider competencies, and SDOH assessment tools and addresses the following questions: (1) What models or frameworks guide healthcare providers to address SDOH? (2) What are the SDOH affecting the delivery of care and the interventions addressing them that affect the care and outcomes of patients with heart failure? (3) What are the opportunities for healthcare providers to address the SDOH affecting the care of patients with heart failure? We also include a case study ( Data Supplement ) that highlights an interprofessional team effort to address and mitigate the effects of SDOH in an underserved patient with heart failure.

Pharmacological interventions for heart failure in people with chronic kidney disease

BACKGROUND

Approximately half of people with heart failure have chronic kidney disease (CKD). Pharmacological interventions for heart failure in people with CKD have the potential to reduce death (any cause) or hospitalisations for decompensated heart failure. However, these interventions are of uncertain benefit and may increase the risk of harm, such as hypotension and electrolyte abnormalities, in those with CKD.

OBJECTIVES

This review aims to look at the benefits and harms of pharmacological interventions for HF (i.e., antihypertensive agents, inotropes, and agents that may improve the heart performance indirectly) in people with HF and CKD.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies through 12 September 2019 in consultation with an Information Specialist and using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We included randomised controlled trials of any pharmacological intervention for acute or chronic heart failure, among people of any age with chronic kidney disease of at least three months duration.

DATA COLLECTION AND ANALYSIS

Two authors independently screened the records to identify eligible studies and extracted data on the following dichotomous outcomes: death, hospitalisations, worsening heart failure, worsening kidney function, hyperkalaemia, and hypotension. We used random effects meta-analysis to estimate treatment effects, which we expressed as a risk ratio (RR) with 95% confidence intervals (CI). We assessed the risk of bias using the Cochrane tool. We applied the GRADE methodology to rate the certainty of evidence.

MAIN RESULTS

One hundred and twelve studies met our selection criteria: 15 were studies of adults with CKD; 16 studies were conducted in the general population but provided subgroup data for people with CKD; and 81 studies included individuals with CKD, however, data for this subgroup were not provided. The risk of bias in all 112 studies was frequently high or unclear. Of the 31 studies (23,762 participants) with data on CKD patients, follow-up ranged from three months to five years, and study size ranged from 16 to 2916 participants. In total, 26 studies (19,612 participants) reported disaggregated and extractable data on at least one outcome of interest for our review and were included in our meta-analyses. In acute heart failure, the effects of adenosine A1-receptor antagonists, dopamine, nesiritide, or serelaxin on death, hospitalisations, worsening heart failure or kidney function, hyperkalaemia, hypotension or quality of life were uncertain due to sparse data or were not reported. In chronic heart failure, the effects of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) (4 studies, 5003 participants: RR 0.85, 95% CI 0.70 to 1.02; I2 = 78%; low certainty evidence), aldosterone antagonists (2 studies, 34 participants: RR 0.61 95% CI 0.06 to 6.59; very low certainty evidence), and vasopressin receptor antagonists (RR 1.26, 95% CI 0.55 to 2.89; 2 studies, 1840 participants; low certainty evidence) on death (any cause) were uncertain. Treatment with beta-blockers may reduce the risk of death (any cause) (4 studies, 3136 participants: RR 0.69, 95% CI 0.60 to 0.79; I2 = 0%; moderate certainty evidence). Treatment with ACEi or ARB (2 studies, 1368 participants: RR 0.90, 95% CI 0.43 to 1.90; I2 = 97%; very low certainty evidence) had uncertain effects on hospitalisation for heart failure, as treatment estimates were consistent with either benefit or harm. Treatment with beta-blockers may decrease hospitalisation for heart failure (3 studies, 2287 participants: RR 0.67, 95% CI 0.43 to 1.05; I2 = 87%; low certainty evidence). Aldosterone antagonists may increase the risk of hyperkalaemia compared to placebo or no treatment (3 studies, 826 participants: RR 2.91, 95% CI 2.03 to 4.17; I2 = 0%; low certainty evidence). Renin inhibitors had uncertain risks of hyperkalaemia (2 studies, 142 participants: RR 0.86, 95% CI 0.49 to 1.49; I2 = 0%; very low certainty). We were unable to estimate whether treatment with sinus node inhibitors affects the risk of hyperkalaemia, as there were few studies and meta-analysis was not possible. Hyperkalaemia was not reported for the CKD subgroup in studies investigating other therapies. The effects of ACEi or ARB, or aldosterone antagonists on worsening heart failure or kidney function, hypotension, or quality of life were uncertain due to sparse data or were not reported. Effects of anti-arrhythmic agents, digoxin, phosphodiesterase inhibitors, renin inhibitors, sinus node inhibitors, vasodilators, and vasopressin receptor antagonists were very uncertain due to the paucity of studies.

AUTHORS' CONCLUSIONS

The effects of pharmacological interventions for heart failure in people with CKD are uncertain and there is insufficient evidence to inform clinical practice. Study data for treatment outcomes in patients with heart failure and CKD are sparse despite the potential impact of kidney impairment on the benefits and harms of treatment. Future research aimed at analysing existing data in general population HF studies to explore the effect in subgroups of patients with CKD, considering stage of disease, may yield valuable insights for the management of people with HF and CKD.

Association of Variants in BAG3 With Cardiomyopathy Outcomes in African American Individuals

Importance

The prevalence of nonischemic dilated cardiomyopathy (DCM) is greater in individuals of African ancestry than in individuals of European ancestry. However, little is known about whether the difference in prevalence or outcomes is associated with functional genetic variants.

Objective

We hypothesized that Bcl2-associated anthanogene 3 (BAG3) genetic variants were associated with outcomes in individuals of African ancestry with DCM.

Design

This multicohort study of the BAG3 genotype in patients of African ancestry with dilated cardiomyopathy uses DNA obtained from African American individuals enrolled in 3 clinical studies: the Genetic Risk Assessment of African Americans With Heart Failure (GRAHF) study; the Intervention in Myocarditis and Acute Cardiomyopathy Trial-2 (IMAC-2) study; and the Genetic Risk Assessment of Cardiac Events (GRACE) study. Samples of DNA were also acquired from the left ventricular myocardium of patients of African ancestry who underwent heart transplant at the University of Colorado and University of Pittsburgh.

Main Outcomes and Measures

The primary end points were the prevalence of BAG3 mutations in African American individuals and event-free survival in participants harboring functional BAG3 mutations.

Results

Four BAG3 genetic variants were identified; these were expressed in 42 of 402 African American individuals (10.4%) with nonischemic heart failure and 9 of 107 African American individuals (8.4%) with ischemic heart failure but were not present in a reference population of European ancestry (P < .001). The variants included 2 nonsynonymous single-nucleotide variants; 1 three-nucleotide in-frame insertion; and 2 single-nucleotide variants that were linked in cis. The presence of BAG3 variants was associated with a nearly 2-fold (hazard ratio, 1.97 [95% CI, 1.19-3.24]; P = .01) increase in cardiac events in carriers compared with noncarriers. Transfection of transformed adult human ventricular myocytes with plasmids expressing the 4 variants demonstrated that each variant caused an increase in apoptosis and a decrease in autophagy when samples were subjected to the stress of hypoxia-reoxygenation.

Conclusions and Relevance

This study demonstrates that genetic variants in BAG3 found almost exclusively in individuals of African ancestry were not causative of disease but were associated with a negative outcome in patients with a dilated cardiomyopathy through modulation of the function of BAG3. The results emphasize the importance of biological differences in causing phenotypic variance across diverse patient populations, the need to include diverse populations in genetic cohorts, and the importance of determining the pathogenicity of genetic variants.

Leveraging Signaling Pathways to Treat Heart Failure With Reduced Ejection Fraction

Advances in the treatment of heart failure with reduced ejection fraction due to systolic dysfunction are engaging an ever-expanding compendium of molecular signaling targets. Well established approaches modifying hemodynamics and cell biology by neurohumoral receptor blockade are evolving, exploring the role and impact of modulating intracellular signaling pathways with more direct myocardial effects. Even well-tread avenues are being reconsidered with new insights into the signaling engaged and thus opportunity to treat underlying myocardial disease. This review explores therapies that have proven successful, those that have not, those that are moving into the clinic but whose utility remains to be confirmed, and those that remain in the experimental realm. The emphasis is on signaling pathways that are tractable for therapeutic manipulation. Of the approaches yet to be tested in humans, we chose those with a well-established experimental history, where clinical translation may be around the corner. The breadth of opportunities bodes well for the next generation of heart failure therapeutics.

Heart failure and endothelial nitric oxide synthase G894T gene polymorphism frequency variations within ancestries

The G894T polymorphism in endothelial nitric oxide synthase enzyme gene plays an important role in heart failure (HF) and its frequency varies among populations. We investigated this association in highly admixed samples in terms of ancestry. The cohort included 210 HF patients and 106 healthy individuals. Self-reported race and NYHA class were analyzed for HF patients. G894T polymorphism was analyzed by polymerase chain reaction (PCR) and by restriction fragment length polymorphism technique. Ancestry was estimated using a PCR reaction containing 46 autosomal ancestry informative markers and an analysis by capillary electrophoresis. The GG homozygous genotype had a higher frequency in HF patients (63.8%) than in healthy individuals (48.1%), showing an increased chance (odds ratio 1.90, 95% confidence interval 1.18-3.05). The ancestry profiles in patients and controls were similar, with a major European contribution (57.1% and 63.2%), followed by African (30.2% and 24.0%) and Native American (12.7% and 12.8%), without a significant difference between both samples (p = 0.28). The GG genotype is associated to HF prognosis, and this association remains present in highly admixed sample groups.

Race Effects of Inhaled Nitric Oxide in Preterm Infants: An Individual Participant Data Meta-Analysis

OBJECTIVE

To assess whether inhaled nitric oxide (iNO) improves survival without bronchopulmonary dysplasia (BPD) for preterm African American infants.

STUDY DESIGN

An individual participant data meta-analysis was conducted, including 3 randomized, placebo-controlled trials that enrolled infants born at  <34 weeks of gestation receiving respiratory support, had at least 15% (or a minimum of 10 infants in each trial arm) of African American race, and used a starting iNO of >5  parts per million with the intention to treat for 7 days minimum. The primary outcome was a composite of death or BPD. Secondary outcomes included death before discharge, postnatal steroid use, gross pulmonary air leak, pulmonary hemorrhage, measures of respiratory support, and duration of hospital stay.

RESULTS

Compared with other races, African American infants had a significant reduction in the composite outcome of death or BPD with iNO treatment: 49% treated vs 63% controls (relative risk, 0.77; 95% CI, 0.65-0.91; P = .003; interaction P = .016). There were no differences between racial groups for death. There was also a significant difference between races (interaction P = .023) of iNO treatment for BPD in survivors, with the greatest effect in African American infants (P = .005). There was no difference between racial groups in the use of postnatal steroids, pulmonary air leak, pulmonary hemorrhage, or other measures of respiratory support.

CONCLUSION

iNO therapy should be considered for preterm African American infants at high risk for BPD. iNO to prevent BPD in African Americans may represent an example of a racially customized therapy for infants.

The profile of selected single nucleotide polymorphisms in patients with hypertension and heart failure with preserved and mid-range ejection fraction

The study aimed to assess the clinical significance of selected single nucleotide polymorphisms (SNPs) in patients with diastolic heart failure (HF): inflammation [-174 G/C Interleukin -6 (IL-6) rs1800795, tumor necrosis factor (TNF)-608 G/A rs1800629], fibrosis [Arg25Pro transforming growth factor β (TGF β) rs1800471], endothelial function [-786 T/C nitric oxide synthase (NOS) rs2070744], glucose and lipid metabolism [Pro12Ala peroxisome proliferator activated receptor (PPAR)γ rs1801282], and vitamin D metabolism [cytochrome P450 27B1 (CYP27B1) C-1260A].110 patients with HF with preserved and mid-range ejection fraction (HFpEF and HFmrEF) were recruited. GG homozygotes in 174 G/C of IL6 polymorphism are characterized by higher values of estimated glomerular filtration rate based on the study Modification of Diet in Renal Disease (eGFR MDRD) and C allele in the NOS polymorphism and AA profile in C-1260A of CYP27B1 polymorphism correlated with a lower eGFR (MDRD). In multivariate analysis the CG genotype for 174 G/C of IL-6 and allele A in C-1260A of CYP27B1 are the only SNPs independently associated with worse course of HFpEF and HFmrEF. These data confirm the importance of the selected SNPs in aggravation and complications of hypertension.

Towards Precision in HF Pharmacotherapy

PURPOSE OF REVIEW

Heart failure (HF) is a disease state with great heterogeneity, which complicates the therapeutic process. Identifying more precise HF phenotypes will allow for the development of more targeted therapies and improvement in patient outcomes. This review explores the future for precision medicine in HF treatment.

RECENT FINDINGS

Rather than a continuous disease spectrum with a uniform pathogenesis, HF has phenotypes with different underlying pathophysiologic features. The challenge is to establish clinical phenotypic characterizations to direct therapy. Phenomapping, a process of using machine learning algorithms applied to clinical data sets, has been used to identify phenotypically distinct and clinically meaningful HF groups. As powerful technologies extend our knowledge, future analyses may be able to compile more comprehensive phenotypic profiles using genetic, epigenetic, proteomic, and metabolomic measurements. Identifying clinical characterizations of particular HF patients that would be uniquely or disproportionately responsive to a specific treatment would allow for more direct selection of optimal therapy, reduce trial-and-error prescribing, and help avoid adverse drug reactions.

Perioperative Inotrope Therapy and Atrial Fibrillation Following Coronary Artery Bypass Graft Surgery: Evidence of a Racial Disparity

BACKGROUND AND OBJECTIVE

Following coronary artery bypass graft (CABG) surgery, mortality rates are significantly higher among black patients who experience postoperative atrial fibrillation (POAF). Perioperative inotropic therapy (PINOT) was associated with POAF in previous reports, but the extent to which race influences this association is unknown. In the present study, the relationship between PINOT, race, and POAF was examined in patients undergoing CABG surgery.

METHODS AND SETTING

Clinical records were examined from a prospectively maintained cohort of 11,855 patients (median age 64 yrs; 70% male; 16% black) undergoing primary isolated CABG at a large cardiovascular institute in the southeastern region of the United States. Relative risk (RR) and 95% confidence intervals (CIs) were computed using log-binomial regression.

MAIN RESULTS

The association between PINOT and POAF was significantly increased among black patients (adjusted RR 1.7, CI 1.4-2.0) compared with white patients (adjusted RR 1.3, CI 1.2-1.4) (p_interaction  = 0.013).

CONCLUSIONS

These findings suggest that PINOT may be disproportionately associated with POAF among black patients undergoing CABG surgery. Additional studies are needed to examine further the potential underlying mechanisms of this association.

Combination of Hydralazine and Isosorbide-Dinitrate in the Treatment of Patients with Heart Failure with Reduced Ejection Fraction

The use of direct acting vasodilators (the combination of hydralazine and isosorbide dinitrate -Hy+ISDN-) in heart failure with reduced ejection fraction (HFrEF) is supported by evidence, but rarely used.However, treatment with Hy+ISDN is guideline-recommended for HFrEF patients who cannot receive either angiotensin-converting enzyme inhibitors or angiotensin receptor blockers due to intolerance or contraindication, and in self-identified African-American HFrEF patients who are symptomatic despite optimal neurohumoral therapy.The Hy+ISDN combination has arterial and venous vasodilating properties. It can decrease preload and afterload, decrease left ventricular end-diastolic diameter and the volume of mitral regurgitation, reduce left atrial and left ventricular wall tension, decrease pulmonary artery pressure and pulmonary arterial wedge pressure, increase stroke volume, and improve left ventricular ejection fraction, as well as induce left ventricular reverse remodelling. Furthermore, Hy+ISDN combination has antioxidant property, it affects endothelial dysfunction beneficially and improves NO bioavailability. Because of these benefits, this combination can improve the signs and symptoms of heart failure, exercise capacity and quality of life, and, most importantly, reduce morbidity and mortality in well-defined subgroups of HFrEF patients.Accordingly, this therapeutic option can in many cases play an essential role in the treatment of HFrEF.

Contextualizing Genetics for Regional Heart Failure Care

Congestive heart failure (CHF) is a chronic and often devastating cardiovascular disorder with no cure. There has been much advancement in the last two decades that has seen improvements in morbidity and mortality. Clinicians have also noted variations in the responses to therapies. More detailed observations also point to clusters of diseases, phenotypic groupings, unusual severity and the rates at which CHF occurs. Medical genetics is playing an increasingly important role in answering some of these observations. This developing field in many respects provides more information than is currently clinically applicable. This includes making sense of the established single gene mutations or uncommon private mutations. In this thematic series which discusses the many factors that could be relevant for CHF care, once established treatments are available in the communities; this section addresses a contextual role for medical genetics.

Pharmacogenomics of heart failure: a systematic review

BACKGROUND

Heart failure (HF) and multiple HF-related phenotypes are heritable. Genes implicated in the HF pathophysiology would be expected to influence the response to treatment.

METHODS

We conducted a series of systematic literature searches on the pharmacogenetics of HF therapy to assess the current knowledge on this field.

RESULTS

Existing data related to HF pharmacogenomics are still limited. The ADRB1 gene is a likely candidate to predict response to β-blockers. Moreover, the cytochrome P450 2D6 coding gene (CYP2D6) clearly affects the pharmacokinetics of metoprolol, although the clinical impact of this association remains to be established.

CONCLUSION

Given the rising prevalence of HF and related costs, a more personalized use of HF drugs could have a remarkable benefit for patients, caregivers and healthcare systems.

GNB3 C825T Polymorphism and Myocardial Recovery in Peripartum Cardiomyopathy: Results of the Multicenter Investigations of Pregnancy-Associated Cardiomyopathy Study

BACKGROUND

Black women are at greater risk for peripartum cardiomyopathy (PPCM). The guanine nucleotide-binding proteins β-3 subunit (GNB3) has a polymorphism C825T. The GNB3 TT genotype more prevalent in blacks is associated with poorer outcomes. We evaluated GNB3 genotype and myocardial recovery in PPCM.

METHODS AND RESULTS

A total of 97 women with PPCM were enrolled and genotyped for the GNB3 T/C polymorphism. Left ventricular ejection fraction (LVEF) was assessed by echocardiography at entry, 6 and 12 months postpartum. LVEF over time in subjects with the GNB3 TT genotype was compared with those with the C allele overall and in black and white subsets. The cohort was 30% black, age 30+6, LVEF 0.34+0.10 at entry 31+25 days postpartum. The % GNB3 genotype for TT/CT/CC=23/41/36 and differed markedly by race (blacks=52/38/10 versus whites=10/44/46, P<0.001). In subjects with the TT genotype, LVEF at entry was lower (TT=0.31+0.09; CT+CC=0.35+0.09, P=0.054) and this difference increased at 6 (TT=0.45+0.15; CT+CC=0.53+0.08, P=0.002) and 12 months (TT=0.45+0.15; CT+CC=0.56+0.07, P<0.001.). The difference in LVEF at 12 months by genotype was most pronounced in blacks (12 months LVEF for GNB3 TT=0.39+0.16; versus CT+CC=0.53+0.09, P=0.02) but evident in whites (TT=0.50++0.11; CT+CC=0.56+0.06, P=0.04).

CONCLUSIONS

The GNB3 TT genotype was associated with lower LVEF at 6 and 12 months in women with PPCM, and this was particularly evident in blacks. Racial differences in the prevalence and impact of GNB3 TT may contribute to poorer outcomes in black women with PPCM.

The future of pharmacogenetics in the treatment of heart failure

Heart failure is a common disease with high levels of morbidity and mortality. Current treatment comprises β-blockers, ACE inhibitors, aldosterone antagonists and diuretics. Variation in clinical response seen in patients begs the question of whether there is a pharmacogenetic component yet to be identified. To date, the genes most studied involve the β-1, β-2, α-2 adrenergic receptors and the renin-angiotensin-aldosterone pathway, mainly focusing on SNPs. However results have been inconsistent. Genome-wide association studies and next-generation sequencing are seen as alternative approaches to discovering genetic variations influencing drug response. Hopefully future research will lay the foundations for genotype-led drug management in these patients with the ultimate aim of improving their clinical outcome.

Right Ventricular Adaptation Is Associated with the Glu298Asp Variant of the NOS3 Gene in Elite Athletes

Nitric oxide (NO), an important endogenous pulmonary vasodilator is synthetized by the endothelial NO synthase (NOS3). Reduced NO bioavailability and thus the Glu298Asp polymorphism of NOS3 may enhance right ventricular (RV) afterload and hypertrophic remodeling and influence athletic performance. To test this hypothesis world class level athletes (water polo players, kayakers, canoeists, rowers, swimmers, n = 126) with a VO2 maximum greater than 50ml/kg/min were compared with non-athletic volunteers (n = 155). Cardiopulmonary exercise tests and cardiac magnetic resonance imaging (cMRI) were performed to determine structural or functional changes. Genotype distribution of the NOS3 Glu298Asp polymorphism was not affected by gender or physical performance. Cardiac MRI showed increased stroke volume with eccentric hypertrophy in all athletes regardless of their genotype. However, the Asp allelic variant carriers had increased RV mass index (32±6g versus 27±6g, p<0.01) and larger RV stroke volume index (71±10ml versus 64±10ml, p<0.01) than athletes with a Glu/Glu genotype. Genotype was not significantly associated with athletic performance. In the non-athletic group no genotype related differences were detected. The association between the NOS3 Glu298Asp polymorphism and RV structure and dimension in elite athletes emphasizes the importance of NOS3 gene function and NO bioavailability in sport related cardiac adaptation.

Endothelial nitric oxide synthase polymorphism and prognosis in systolic heart failure patients

BACKGROUND

The endothelial nitric oxide synthase (eNOS) gene single nucleotide polymorphism G894T is associated with thrombotic vascular diseases. However, its functional significance is controversial and data are scarce concerning its influence in heart failure (HF).

METHODS

We studied 215 patients with chronic systolic HF. DNA was analyzed for eNOS gene G894T polymorphism using PCR and DNA sequencing. Evaluation of clinical characteristics and analysis of factors associated with 2-year mortality were performed for the homozygous G-allele G894T variant (GG), relative to the TT and GT variants.

RESULTS

The genotype distributions of eNOS G894T alleles were: GG 135 patients (63%) and TT/GT 80 (37%). Two-year mortality was significantly higher in the GG variant (48%) than the combined TT/GT group (32%). The usage of nitrates was associated with increased 2-year mortality (HR 2.0, 95% CI 1.28-3.17; p = 0.003), which was most significant in the GG group treated with nitrates (73.5%) in comparison to the TT/GT group not treated with nitrates (34%); HR 2.75, 95% CI 1.57-4.79, P < 0.001.

CONCLUSIONS

Homozygosity for the G allele of the eNOS G894T polymorphism was associated with worse survival in systolic HF patients, especially in those treated with nitrates. ENOS polymorphism may result in different mechanistic interactions in HF than in thrombotic vascular diseases, suggesting that overexpression of NO may be associated with deleterious effects in systolic HF.

Genetic variants are not associated with outcome in patients with coronary artery disease and left ventricular dysfunction: results of the Genetic Substudy of the Surgical Treatment for Ischemic Heart Failure (STICH) trials

OBJECTIVES AND BACKGROUND

We evaluated the ability of 23 genetic variants to provide prognostic information in patients enrolled in the Genetic Substudy of the Surgical Treatment for Ischemic Heart Failure (STICH) trials.

METHODS

Patients assigned to STICH Hypothesis 1 were randomized to medical therapy with or without coronary artery bypass grafting (CABG). Those assigned to STICH Hypothesis 2 were randomized to CABG or CABG with left ventricular reconstruction.

RESULTS

In patients assigned to STICH Hypothesis 2 (n = 714), no genetic variant met the prespecified Bonferroni-adjusted threshold for statistical significance (p < 0.002); however, several variants met nominal prognostic significance: variants in the β2-adrenergic receptor gene (β2-AR Gln27Glu) and in the A1-adenosine receptor gene (A1-717 T/G) were associated with an increased risk of a subject dying or being hospitalized for a cardiac problem (p = 0.027 and 0.031, respectively). These relationships remained nominally significant even after multivariable adjustment for prognostic clinical variables. However, none of the 23 genetic variants influenced all-cause mortality or the combination of death or cardiovascular hospitalization in the STICH Hypothesis 1 population (n = 532) by either univariate or multivariable analysis.

CONCLUSION

We were unable to identify the predictive genotypes in optimally treated patients in these two ischemic heart failure populations.

Race, common genetic variation, and therapeutic response disparities in heart failure

Because of its comparatively recent evolution, Homo sapiens exhibit relatively little within-species genomic diversity. However, because of genome size, a proportionately small amount of variation creates ample opportunities for both rare mutations that may cause disease as well as more common genetic variations that may be important in disease modification or pharmacogenetics. Primarily because of the East African origin of modern humans, individuals of African ancestry (AA) exhibit greater degrees of genetic diversity than more recently established populations, such as those of European ancestry (EA) or Asian ancestry. Those population effects extend to differences in frequency of common gene variants that may be important in heart failure natural history or therapy. For cell-signaling mechanisms important in heart failure, we review and present new data for genetic variation between AA and EA populations. Data indicate that: 1) neurohormonal signaling mechanisms frequently (16 of the 19 investigated polymorphisms) exhibit racial differences in the allele frequencies of variants comprising key constituents; 2) some of these differences in allele frequency may differentially affect the natural history of heart failure in AA compared with EA individuals; and 3) in many cases, these differences likely play a role in observed racial differences in drug or device response.

G-protein beta-3 subunit genotype predicts enhanced benefit of fixed-dose isosorbide dinitrate and hydralazine: results of A-HeFT

OBJECTIVES

The purpose of this study was to evaluate the influence of the guanine nucleotide-binding proteins (G-proteins), beta-3 subunit (GNB3) genotype on the effectiveness of a fixed-dose combination of isosorbide dinitrate and hydralazine (FDC I/H) in A-HeFT (African American Heart Failure Trial).

BACKGROUND

GNB3 plays a role in alpha2-adrenergic signaling. A polymorphism (C825T) exists, and the T allele is linked to enhanced alpha-adrenergic tone and is more prevalent in African Americans.

METHODS

A total of 350 subjects enrolled in the genetic substudy (GRAHF [Genetic Risk Assessment of Heart Failure in African Americans]) were genotyped for the C825T polymorphism. The impact of FDC I/H on a composite score (CS) that incorporated death, hospital stay for heart failure, and change in quality of life (QoL) and on event-free survival were assessed in GNB3 genotype subsets.

RESULTS

The GRAHF cohort was 60% male, 25% ischemic, 97% New York Heart Association functional class III, age 57 ± 13 years, with a mean qualifying left ventricular ejection fraction of 0.24 ± 0.06. For GNB3 genotype, 184 subjects were TT (53%), 137 (39%) CT, and 29 (8%) were CC. In GNB3 TT subjects, FDC I/H improved the CS (FDC I/H = 0.50 ± 1.6; placebo = -0.11 ± 1.8, p = 0.02), QoL (FDC I/H = 0.69 ± 1.4; placebo = 0.24 ± 1.5, p = 0.04), and event-free survival (hazard ratio: 0.51, p = 0.047), but not in subjects with the C allele (for CS, FDC I/H = -0.05 ± 1.7; placebo = -0.09 ± 1.7, p = 0.87; for QoL, FDC I/H = 0.28 ± 1.5; placebo = 0.14 ± 1.5, p = 0.56; and for event-free survival, p = 0.35).

CONCLUSIONS

The GNB3 TT genotype was associated with greater therapeutic effect of FDC I/H in A-HeFT. The role of the GNB3 genotype for targeting therapy with FDC I/H deserves further study.

BiDil in the Clinic: An Interdisciplinary Investigation of Physicians' Prescription Patterns of a Race-Based Therapy

BACKGROUND

The African American Heart Failure Trial (A-HeFT) and the FDA approval of BiDil for race-specific prescription have stirred the debate about the scientific and medical status of race. Yet there is no assessment of the potential fallouts of this dispute on physicians' willingness to prescribe the drug. We present here an analysis of the factors influencing physicians' prescription of BiDil and investigate whether exposure to the controversy has an impact on their therapeutic judgments about the drug.

METHODS

We conducted an electronic survey with physicians in the department of internal medicine at the University of Cincinnati. Participants were randomly assigned to two groups, with one group receiving information about the controversy over BiDil. We used various statistical tests, including a linear mixed effects model, to analyze the results.

RESULTS

27% of the participants reported using patients' race as a major factor in making treatment decisions. 33% reported the inefficacy of standard therapies, 25% the severity of the disease, and 15% other unspecified factors as primary determining criteria in prescribing BiDil. With respect to the controversy, 68% of physicians reported that they were not aware of any controversy surrounding BiDil. Physicians' willingness to prescribe BiDil as a therapy was associated with their awareness of the controversy surrounding A-HeFT (p < 0.003). But their willingness to prescribe the therapy along racial lines did not vary significantly with exposure to the controversy.

CONCLUSIONS

Overall, physicians prescribe and are willing to prescribe BiDil more to black patients than to white patients. However, physicians' lack of awareness about the controversial scientific status of A-HeFT suggests the need for more efficient ways to convey scientific information about BiDil to clinicians. Furthermore, the uncertainties about the determination of clinical utility of BiDil for the individual patient raise questions about whether this specific race-based therapy is in patients' best interest.

Use of isosorbide dinitrate and hydralazine in African-Americans with heart failure 9 years after the African-American Heart Failure Trial

The 2013 American College of Cardiology Foundation/American Heart Association guidelines recommend combined isosorbide dinitrate (ISDN) and hydralazine to reduce mortality and morbidity for African-Americans with symptomatic heart failure (HF) and reduced ejection fraction, currently receiving optimal medical therapy (class I, level A). Nitrates can alleviate HF symptoms, but continuous use is limited by tolerance. Hydralazine may mitigate nitrate tolerance, and the ISDN-hydralazine combination in the Vasodilators in Heart Failure Trial (V-HeFT) I improved survival and exercise tolerance in men with dilated cardiomyopathy or HF with reduced ejection fraction, most notably in self-identified black participants. In the subsequent V-HeFT II, survival was greater with enalapril than with ISDN-hydralazine in the overall cohort, but mortality rate was similar in the enalapril and ISDN-hydralazine groups in the self-identified black patients. Consequently, in the African-American Heart Failure Trial (A-HeFT) in self-identified black patients with symptomatic HF, adding a fixed-dose combination ISDN-hydralazine to modern guideline-based care improved outcomes versus placebo, including all-cause mortality, and led to early trial termination. Hypertension underlies HF, especially in African-Americans; the A-HeFT and its substudies demonstrated not only improvements in echocardiographic parameters, morbidity, and mortality but also a decrease in hospitalizations, potentially affecting burgeoning HF health-care costs. Genetic characteristics may, therefore, determine response to ISDN-hydralazine, and the Genetic Risk Assessment in Heart Failure substudy demonstrated important hypothesis-generating pharmacogenetic data.

Asymmetric dimethylarginine, race, and mortality in hemodialysis patients

BACKGROUND AND OBJECTIVES

Levels of asymmetric dimethylarginine, an inhibitor of nitric oxide synthase, are elevated in kidney disease and associated with mortality in white European hemodialysis populations. Nitric oxide production and degradation are partially genetically determined and differ by racial background. No studies have measured asymmetric dimethylarginine in African Americans on dialysis and assessed whether differences exist in its association with mortality by race.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Asymmetric dimethylarginine was measured in 259 patients on maintenance hemodialysis assembled from 2004 to 2012 in Boston area outpatient centers. Cox proportional hazards models were used to determine the association between asymmetric dimethylarginine and all-cause mortality, and an interaction with race was tested.

RESULTS

Mean (SD) age was 63 (17) years, 46% were women, and 22% were African American. Mean asymmetric dimethylarginine in non-African Americans was 0.79 µmol/L (0.16) versus 0.70 µmol/L (0.11) in African Americans (P<0.001); 130 patients died over a median follow-up of 2.3 years. African Americans had lower mortality risk than non-African Americans (hazard ratio, 0.27; 95% confidence interval, 0.15 to 0.50) that was robust to adjustment for age, comorbidity, and asymmetric dimethylarginine (hazard ratio, 0.35; 95% confidence interval, 0.17 to 0.69). An interaction was noted between race and asymmetric dimethylarginine (P=0.03), such that asymmetric dimethylarginine was associated with higher mortality in non-African Americans (adjusted hazard ratio, 1.29; 95% confidence interval, 1.06 to 1.57 per 1 SD higher asymmetric dimethylarginine) but not in African Americans (adjusted hazard ratio, 0.57; 95% confidence interval, 0.28 to 1.18). Additional adjustment for fibroblast growth factor 23 partially attenuated the association for non-African Americans (adjusted hazard ratio, 1.22; 95% confidence interval, 0.98 to 1.50).

CONCLUSIONS

African Americans have lower asymmetric dimethylarginine levels and lower hazard for mortality compared with non-African Americans. Levels of asymmetric dimethylarginine did not explain lower hazard for mortality in non-African American patients. High asymmetric dimethylarginine was a risk factor for mortality exclusively in non-African Americans. Mechanisms explaining these relationships need to be evaluated.

Genetic polymorphism G894T and the prognosis of heart failure outpatients

BACKGROUND

Previous studies have analyzed the role of the genetic polymorphism of endothelial nitric oxide synthase on heart failure prognosis. However, there are no studies relating the G894T and heart failure in Brazil.

OBJECTIVE

To evaluate the association between G894T GP and the prognosis of a sample of Brazilian outpatients with heart failure.

METHODS

Cohort study included 145 patients with systolic heart failure, followed for up to 40 months (mean = 22), at two university hospitals, in the State of Rio de Janeiro. We evaluated the relationship between G894T and the following outcomes: reverse remodeling, improvement in functional class (NYHA), and mortality and hospitalization rates. The diameters of the left atrium and ventricle, as well as the ejection fraction of the left ventricle, were evaluated at baseline and at 6 months to assess reverse remodeling. The improvement in functional class was evaluated after 6 months, and mortality rate and hospitalization were evaluated during follow-up. Race was self-declared. G894T polymorphism was analyzed by polymerase chain reaction and restriction fragment length polymorphism.

RESULTS

The genotypic frequencies were GG (40%), GT (48.3%) and TT (11.7%). The allele frequency was guanine (64.1%) and thiamine (35.8%). There were no differences between the genotype or allelic frequencies according to self-declared race, either as baseline characteristics. There was no relationship between genotype or allele frequency and the outcome measures.

CONCLUSION

No association was observed between the G894T polymorphism (Glu298Asp) and prognosis in this sample of Brazilian outpatients with systolic heart failure.

Haplotypes of NOS3 gene polymorphisms in dilated cardiomyopathy

Dilated Cardiomyopathy (DCM) is characterized by systolic dysfunction, followed by heart failure necessitating cardiac transplantation. The genetic basis is well established by the identification of mutations in sarcomere and cytoskeleton gene/s. Modifier genes and environmental factors are also considered to play a significant role in the variable expression of the disease, hence various mechanisms are implicated and one such mechanism is oxidative stress. Nitric Oxide (NO), a primary physiological transmitter derived from endothelium seems to play a composite role with diverse anti-atherogenic effects as vasodilator. Three functional polymorphisms of endothelial nitric oxide synthase (NOS3) gene viz., T-786C of the 5′ flanking region, 27bp VNTR in intron4 and G894T of exon 7 were genotyped to identify their role in DCM. A total of 115 DCM samples and 454 controls were included. Genotyping was carried out by PCR -RFLP method. Allelic and genotypic frequencies were computed in both control & patient groups and appropriate statistical tests were employed. A significant association of TC genotype (T-786C) with an odds ratio of 1.74, (95% CI 1.14 - 2.67, p = 0.01) was observed in DCM. Likewise the GT genotypic frequency of G894T polymorphism was found to be statistically significant (OR 2.10, 95% CI 1.34–3.27, p = 0.0011), with the recessive allele T being significantly associated with DCM (OR 1.64, 95% CI 1.18 - 2.30, p = 0.003). The haplotype carrying the recessive alleles of G894T and T-786C, C4bT was found to exhibit 7 folds increased risk for DCM compared to the controls. Hence C4bT haplotype could be the risk haplotype for DCM. Our findings suggest the possible implication of NOS3 gene in the disease phenotype, wherein NOS3 may be synergistically functioning in DCM associated heart failure via the excessive production of NO in cardiomyocytes resulting in decreased myocardial contractility and systolic dysfunction, a common feature of DCM phenotype.

Personalized healthcare in the era of value-based healthcare

Medical care in the USA is plagued by high costs, poor quality and fragmented care delivery. In response, new methods of integrated healthcare delivery are needed, including the patient-centered medical home. At the same time, we need to revitalize our approach to the practice of medicine, moving to a personalized approach, even as we increasingly focus on population management. Some aspects of personalized healthcare have the potential to add significant cost to the system, while others can improve value. This article aims to provide an overview of the current healthcare climate, discuss evolving models of care in the era of healthcare reform and describe the increasingly important role of personalized healthcare in this process.

The 894G Allele of the Endothelial Nitric Oxide Synthase 3 (eNOS) is Associated with Atrial Fibrillation in Chronic Systolic Heart Failure

BACKGROUND

Atrial fibrillation (AF) in patients with heart failure signals poor prognosis. The endothelial nitric oxide synthase (eNOS) enzyme is a key player in the counterregulation of oxidative stress, which is related in part to AF pathogenesis. The purpose of this study was to investigate a possible clinical association in heart failure patients between the presence of exon 7 G894T eNOS polymorphism, known to result in the Glu298Asp protein variant, and the occurrence of AF.

METHODS

We analyzed the DNA of 344 patients with chronic systolic heart failure for exon 7 G894T eNOS polymorphism, using PCR. Odds ratios for AF were calculated for the homo- and heterozygous G-allele G894T variants relative to the TT variant.

RESULTS

Of the 344 patients, 204 (59%) were homozygous for the G allele, 122 (36%) were heterozygous (GT), and 18 (5%) were homozygous for the T allele. AF episodes were documented in 73 patients (36%) with the GG genotype, in 35 (29%) with GT, and in 2 (11%) with TT. The odds ratio for AF, based on the presence of at least one G allele in the eNOS 894 gene, was 3.96 (95% confidence interval, 1.17‒13.56, p=0.04). Having two G alleles increased the odds ratio to 4.5 (95% confidence interval, 1.0‒20.0, p=0.02).

CONCLUSION

Patients with systolic heart failure demonstrate strong correlation between AF and the presence of a G allele in the exon 7 G894T eNOS genotype. These findings support the importance of eNOS polymorphism in the pathogenesis of AF in heart failure patients.

β-adrenergic receptor polymorphisms in susceptibility, response to treatment and prognosis in heart failure: implication of ethnicity

Common functional polymorphisms in β-adrenergic receptor (βAR) genes have been associated with heart failure (HF) phenotypes and pharmacogenetic interactions with βAR blockers. This study evaluated the association between βAR polymorphisms and carvedilol drug response and prognosis in patients with HF. In this prospective cohort controlled study, 326 volunteers were enrolled [146 HF patients (ejection fraction (EF)<50% by Simpson) and 180 healthy controls]. Drug response was evaluated by echocardiography and outcomes were mortality and hospitalization. DNA was extracted from peripheral blood leukocytes, fragments were amplified by the polymerase reaction and genotyped by restriction fragment length polymorphism (RFLP) for Ser49Gly and Arg389Gly βAR-1 polymorphisms and Gln27Glu and Arg16Gly βAR-2 polymorphisms. The study population was in Hardy‑Weinberg equilibrium. The survival rate was adjusted using the Kaplan-Meier method. HF patients showed the following characteristics: EF 35±9%, 69.9% male, age 59±13 years, 50.7% self-identified as black, 46% had ischemic etiology. The mean follow-up of 23 months showed 18 mortalities and 46 hospitalizations. The genotypes Glu27Glu (24.7 vs. 6.1%, p=0.0004) and Arg16Arg (72.6 vs. 22.8, p<0.0001) of βAR2 polymorphisms and Gly49Gly (33.6 vs. 4.3%, p<0.0001) of the βAR1 polymorphism were higher in HF patients compared with controls. Patients with hospital admission showed a significantly higher Gly389 allelic frequency (54.9 vs. 42.1%, p=0.039), and the trend prevailed among patients who succumbed to the disease (61.1%, p=0.047). Black patients with the Ser49Ser genotype showed a reduced survival compared with the Gly49Gly or Ser49Gly genotypes (p=0.028). There was no association between improved LVEF >20% and βAR polymorphisms. HF patients with β-blocker therapy and the Gly389 allele have reduced event-free survival compared to those carrying the Arg389 allele. Additionally, systolic HF outpatients undergoing β-blocker therapy, self‑identified as black and homozygous for Ser49Ser may have reduced event-free survival, while Glu27Glu, Arg16Arg and Gly49Gly genotypes may be associated with risk for HF.

Pharmacogenetics in chronic heart failure: new developments and current challenges

The individual patient responses to chronic heart failure (HF) pharmacotherapies are highly variable. This variability cannot be entirely explained by clinical characteristics, and genetic variation may play a role. Therefore, this review will summarize the background pharmacogenetic literature for major HF pharmacotherapy classes (ie, β-blockers, angiotensin-converting enzyme inhibitors, digoxin, and loop diuretics), evaluate recent advances in the HF pharmacogenetic literature in the context of previous findings, and discuss the challenges and conclusions for HF pharmacogenetic data and its clinical application.

Contemporary medical management of systolic heart failure

Pharmacological therapy of systolic left ventricular dysfunction has evolved over the past 3 decades. Current therapy is focused primarily on the regulation of the renin-angiotensin-aldosterone axis and sympathetic nervous system. Additional targets of pharmacotherapy include vasoconstriction, impaired nitric oxide metabolism, inflammation and improving myocardial function. As therapies in chronic systolic heart failure have evolved beyond diuretics and digoxin, so too has mortality improved. Future directions in the management of heart failure include cell-based and genetic therapy, and further refinement of current therapy through genetics.

Future of personalized pharmacotherapy in chronic heart failure patients

There is a significant amount of diversity among heart failure (HF) patients. Contemporary HF regimens often do not take into consideration many of the factors that might influence an individual’s response to treatment. Clinical recommendations based on trial data derived from mainly younger Caucasian male study populations have, in most cases, been applied equally to women and African–Americans. Subgroup analyses of randomized HF trials and results of retrospective cohort studies have been used for customizing HF regimens in women and African–Americans. Pharmacogenetics is an emerging strategy for personalizing HF therapy. Genetic biomarkers may play an important role in predicting a patient’s response to treatment and in predicting those at risk of toxicity. HF pharmacotherapy has improved over the last two decades; however, substantial work remains in order to personalize HF management and maximize the benefit of pharmacologic interventions, while limiting adverse events.

Polymorphisms of matrix metalloproteinases in systolic heart failure: role on disease susceptibility, phenotypic characteristics, and prognosis

BACKGROUND

The role of matrix metalloproteinases (MMPs) polymorphisms on heart failure (HF) susceptibility, phenotypic characteristics, and prognosis has been poorly explored.

METHODS AND RESULTS

We studied 313 HF patients with left ventricular systolic dysfunction and 367 healthy control subjects. Genotyping of MMP-1 (-1607 1G/2G), MMP-3 (-1171 5A/6A), and MMP-9 (-1562 C/T) polymorphisms was performed by polymerase chain reaction. Allelic and genotypic frequencies of MMP-1, -3, and -9 were similar in HF patients and controls. MMP1 2G allele carriers were positively associated to ischemic etiology and history of myocardial infarction (all P values <.05). Patients were followed-up for a median of 40 months and 58 HF-related deaths occurred during this period. HF-related survival was significantly better in MMP1 2G allele carriers (71% versus 42% for 1G/1G patients, P = .002) and in MMP-3 6A allele carriers (70% versus 61% for 5A/5A patients, P = .064), particularly in non-ischemic patients (P = .039). MMP1 2G allele was independently associated to HF survival after adjustment for several other predictors of risk (hazard ratio 0.47, 95% confidence interval 0.27 to 0.82; P = .008).

CONCLUSIONS

MMP-1, -3, and -9 polymorphisms were not associated to HF susceptibility. However, MMP1 2G allele carriers were related to a higher prevalence of ischemic etiology among patients with systolic HF and better HF-related prognosis.