Effect of fixed-dose combined isosorbide dinitrate/hydralazine in elderly patients in the African-American heart failure trial.

BACKGROUND: Fixed-dose combined isosorbide dinitrate/hydralazine (FDC I/H) significantly improved outcomes in patients with advanced heart failure (HF) receiving background neurohormonal therapy in the African-American Heart Failure Trial (A-HeFT). In this analysis, we investigated treatment effects by age <65 or ≥65 years. METHODS AND RESULTS: Time-to-event curves were produced by the Kaplan-Meier method. Hazard ratios were calculated with the Cox proportional hazards model. Baseline characteristics showed that patients ≥65 years old had less hypertensive and more ischemic HF, better quality of life (QoL) scores, higher plasma B-type natriuretic peptide and creatinine levels, and received less background neurohormonal therapy. Kaplan-Meier curves showed that FDC I/H improved mortality and event-free survival in elderly patients. The hazard ratios for mortality, first heart failure hospitalization, and event-free survival (both unadjusted and adjusted for baseline differences), were similar quantitatively and in direction of effect in both age groups. CONCLUSIONS: In A-HeFT, FDC I/H improved outcomes in HF patients aged <65 or ≥65 years, despite significant baseline differences between these age groups. Patients aged ≥65 years, a group at greater mortality risk, had the greatest survival benefit from FDC I/H.

Atrial fibrillation and mortality in African American patients with heart failure: results from the African American Heart Failure Trial (A-HeFT).

BACKGROUND: Atrial fibrillation (AF) is common in patients with heart failure (HF) and portends a worsened prognosis. Because of the low enrollment of African American subjects (AAs) in randomized HF trials, there are little data on AF in AAs with HF. This post hoc analysis reviews characteristics and outcomes of AA patients with AF in A-HeFT. METHODS AND RESULTS: A total of 1,050 AA patients with New York Heart Association class III/IV systolic HF, well treated with neurohormonal blockade (87% ß-blockers, 93% angiotensin-converting enzyme inhibitor and/or angiotensin receptor blocker), were randomized to an added fixed-dose combination of isosorbide dinitrate/hydralazine (FDC I/H) or placebo. Atrial fibrillation was confirmed in 174 (16.6%) patients at baseline and in an additional 9 patients who developed AF during the study, for a final cohort of 183 (17.4%). Comparison of patients with AF versus no AF revealed the following: mean age 61 ± 12 versus 56 ± 13 years (P < .001), systolic blood pressure (BP) 124 ± 18 versus 127 ± 18 mm Hg (P = .044), diastolic BP 74 ± 11 versus 77 ± 10 mm Hg (P = .002), creatinine level 1.4 ± 0.5 versus 1.2 ± 0.5 mg/dL (P < .001), and brain natriuretic peptide 431 ± 443 versus 283 ± 396 pg/mL (P < .001). No significant difference was observed in ejection fraction, left ventricular end-diastolic diameter, or quality-of-life scores. However, AF increased the risk of mortality significantly among AA patients (P = .018), and the use of FDC I/H reduced the risk of mortality in patients with AF (HR 0.21, P = .002). CONCLUSION: African Americans with HF and AF (vs no AF) were older, had lower BP, and had higher creatinine and brain natriuretic peptide levels. Mortality and morbidity were worse when AF was present, and these data suggest that there may be an enhanced survival benefit with the use of FDC I/H in AA patients with HF and AF.

Relationship of quality of life scores with baseline characteristics and outcomes in the African-American heart failure trial.

BACKGROUND: To characterize the quality of life (QOL) in the African-American Heart Failure Trial (A-HeFT) for factors associated with baseline score, relation of score to prognosis, and response to therapy with a fixed-dose combination of isosorbide dinitrate/hydralazine (FDC I/H). Limited data exist on QOL scores in African-American heart failure patients or on the prognostic value of theses scores in any population. Finally, the effect of FDC I/H on QOL scores, particularly in A-HeFT, is not known. METHODS AND RESULTS: A-HeFT randomized 1050 African-American patients with New York Heart Association (NYHA) Class III-IV heart failure and systolic dysfunction. QOL measurements using Minnesota Living with Heart Failure Questionnaire (MLHFQ) were done at baseline and 3-month intervals. At baseline, worse MLHFQ scores were associated with younger age, female sex, greater body mass index, nonischemic etiology, high heart rate and NYHA Class, low systolic blood pressure, and chronic obstructive pulmonary disease. Both baseline and change in MLHFQ score were associated with a higher risk for combined all-cause mortality or heart failure hospitalization (baseline P < .0001, change at 3 months P=.001, and at 6 months P=.0008), but not mortality. Treatment with FDC I/H significantly improved MLHFQ score compared with placebo. CONCLUSIONS: In A-HeFT, baseline QOL (MLHFQ) scores and change in score were predictive of combined HF morbidity and mortality outcomes. FDC I/H consistently improved QOL scores in A-HeFT compared with placebo.

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

BACKGROUND: Genetic heterogeneity at the endothelial nitric oxide synthase (NOS3) locus influences heart failure outcomes. The prevalence of NOS3 variants differs in black and white cohorts, but the impact of these differences is unknown. METHODS AND RESULTS: Subjects (n = 352) in the Genetic Risk Assessment of Heart Failure (GRAHF) substudy of the African-American Heart Failure Trial were genotyped for NOS3 polymorphisms: -786 T/C promoter, intron 4a/4b, and Glu298Asp and allele frequencies and compared with a white heart failure cohort. The effect of treatment with fixed-dose combination of isosorbide dinitrates and hydralazine (FDC I/H) on event-free survival and composite score (CS) of survival, hospitalization, and quality of life (QoL) was analyzed within genotype subsets. In GRAHF, NOS3 genotype frequencies differed from the white cohort (P < .001). The -786 T allele was associated with lower left ventricular ejection fraction (LVEF) (P = .01), whereas the intron 4a allele was linked to lower diastolic blood pressure and higher LVEF (P = .03). Only the Glu298Asp polymorphism influenced treatment outcome; therapy with FDC I/H improved CS (P = .046) and QoL (P = .03) in the Glu298Glu subset only. CONCLUSIONS: In black subjects with heart failure, NOS3 genotype influences blood pressure and left ventricular remodeling. The impact of genetic heterogeneity on treatment with FDC I/H requires further study.

Early and sustained benefit on event-free survival and heart failure hospitalization from fixed-dose combination of isosorbide dinitrate/hydralazine: consistency across subgroups in the African-American Heart Failure Trial.

BACKGROUND: We previously reported that the fixed-dose combination of isosorbide dinitrate and hydralazine hydrochloride (FDC I/H) significantly decreased the risk of all-cause death and first hospitalization for heart failure (HF) and improved quality of life in patients with New York Heart Association class III or IV heart failure in the African-American Heart Failure Trial (A-HeFT). The current analyses further define the effect of FDC I/H on the timing of event-free survival (mortality or first hospitalization for HF) and time to first hospitalization for HF, as well as effects by subgroups and effects on cause-specific mortality. METHODS AND RESULTS: Kaplan-Meier analyses of the 1050 A-HeFT patients on standard neurohormonal blockade demonstrated that FDC I/H produced a 37% improvement in event-free survival (P<0.001) and a 39% reduction in the risk for first hospitalization for HF (P<0.001). These benefits appeared to emerge early (at approximately 50 days of treatment) and were sustained through the duration of the trial. Subgroup analyses of treatment effect by age, sex, baseline blood pressure, history of chronic renal insufficiency, presence of diabetes mellitus, cause of HF, and baseline medication usage demonstrated consistent beneficial effect of FDC I/H on the primary composite score and event-free survival across all subgroups. Mortality from pump failure was reduced by 75% (P=0.012). CONCLUSIONS: FDC I/H treatment of black patients with moderate to severe HF who were taking neurohormonal blockers produced early and sustained significant improvement in event-free survival and hospitalization for HF in the A-HeFT cohort, with significant reduction in mortality from cardiovascular and pump failure deaths. The treatment effects on the primary composite end point and event-free survival were consistent across subgroups.

Exploring the potential synergistic action of spironolactone on nitric oxide-enhancing therapy: insights from the African-American Heart Failure Trial.

BACKGROUND: To investigate if treatment with an aldosterone antagonist affects the outcomes of treatment by fixed dose combination of isosorbide dinitrate/hydralazine (FDC I/H) or placebo in black heart failure (HF) patients treated with contemporary HF medications. In the African-American Heart Failure Trial (A-HeFT), FDC I/H was effective in reducing mortality and improving event-free survival. The beneficial effects of aldosterone antagonist (spironolactone [SP]), however have not been adequately assessed in black patients with or without the use of FDC I/H. METHODS AND RESULTS: A retrospective analysis was performed in A-HeFT data base (n = 1050) to determine the effect of using SP (39% of patients) on outcomes. Baseline comparisons were done by 2-sample t-test or Fisher's exact test. Kaplan-Meier survival analyses were used for comparing between and within groups for outcomes. SP had no effect on mortality, event-free survival, or first HF hospitalization in the overall A-HeFT population. However, SP decreased mortality risk in the FDC I/H group by 59% (P = .03), and a favorable trend was noted on event-free survival and first HF hospitalization. In contrast, the use of SP was not associated with a decrease in mortality or HF hospitalizations in the placebo group. CONCLUSIONS: This study suggests that in black patients with systolic heart failure on standard therapy of beta-blockers and angiotensin-converting enzyme inhibitors/angiotensin receptor antagonists, the beneficial effects of aldosterone antagonists require a background therapy of FDC I/H.

Combination of isosorbide dinitrate and hydralazine in blacks with heart failure.

BACKGROUND: We examined whether a fixed dose of both isosorbide dinitrate and hydralazine provides additional benefit in blacks with advanced heart failure, a subgroup previously noted to have a favorable response to this therapy. METHODS: A total of 1050 black patients who had New York Heart Association class III or IV heart failure with dilated ventricles were randomly assigned to receive a fixed dose of isosorbide dinitrate plus hydralazine or placebo in addition to standard therapy for heart failure. The primary end point was a composite score made up of weighted values for death from any cause, a first hospitalization for heart failure, and change in the quality of life. RESULTS: The study was terminated early owing to a significantly higher mortality rate in the placebo group than in the group given isosorbide dinitrate plus hydralazine (10.2 percent vs. 6.2 percent, P=0.02). The mean primary composite score was significantly better in the group given isosorbide dinitrate plus hydralazine than in the placebo group (-0.1+/-1.9 vs. -0.5+/-2.0, P=0.01; range of possible values, -6 to +2), as were its individual components (43 percent reduction in the rate of death from any cause [hazard ratio, 0.57; P=0.01] 33 percent relative reduction in the rate of first hospitalization for heart failure [16.4 percent vs. 22.4 percent, P=0.001], and an improvement in the quality of life [change in score, -5.6+/-20.6 vs. -2.7+/-21.2, with lower scores indicating better quality of life; P=0.02; range of possible values, 0 to 105]). CONCLUSIONS: The addition of a fixed dose of isosorbide dinitrate plus hydralazine to standard therapy for heart failure including neurohormonal blockers is efficacious and increases survival among black patients with advanced heart failure.

Lack of bioequivalence between different formulations of isosorbide dinitrate and hydralazine and the fixed-dose combination of isosorbide dinitrate/hydralazine: the V-HeFT paradox.

OBJECTIVE: To investigate whether the apparent discrepancy between the efficacy of the combination of isosorbide dinitrate (ISDN) and hydralazine demonstrated in the first V-HeFT trial (V-HeFT I) and that in V-HeFT II could be explained by pharmacokinetic differences in the study drug formulations, and to compare the pharmacokinetic profile of the fixed-dose combination of ISDN/hydralazine (FDC ISDN/HYD; BiDil) formulation used in A-HeFT with that of the V-HeFT study drug formulations. STUDY PARTICIPANTS AND METHODS: A bioequivalence study was performed (n = 18-19 per group) comparing the ISDN and hydralazine formulations used in V-HeFT I, V-HeFT II and A-HeFT in healthy volunteer men and women aged 18-40 years. In phase A of the study, subjects received a reference solution of hydralazine hydrochloride/ISDN (37.5mg/10mg) orally. Slow acetylators were identified and randomised into three groups in phase B to receive a single oral dose of identical amounts of hydralazine hydrochloride/ISDN (37.5mg/10mg) from either (i) a hydralazine capsule plus an ISDN tablet (the V-HeFT I formulation); (ii) a hydralazine tablet plus an ISDN tablet (the V-HeFT II formulation); or (iii) FDC ISDN/HYD (the A-HeFT formulation). Blood/plasma concentrations of hydralazine and ISDN were determined from the blood samples taken between 0 and 36 hours. RESULTS: In phase B, the maximum observed concentrations (C(max)) were 65.9 +/- 53.9, 28.2 +/- 15.8 and 51.5 +/- 54.3 ng/mL of unchanged hydralazine, and 23.1 +/- 12.3, 21.7 +/- 13.4 and 26.7 +/- 18.7 ng/mL of ISDN for the V-HeFT I, V-HeFT II and A-HeFT formulations, respectively. The area under the blood/plasma concentration-time curve (AUC) values were 32.6 +/- 13.4, 23.3 +/- 15.1 and 32.6 +/- 18.5 ng x h/mL of hydralazine, and 24.4 +/- 9.0, 24.8 +/- 8.0 and 23.5 +/- 6.3 ng x h/mL of ISDN for the V-HeFT I, V-HeFT II and A-HeFT formulations, respectively. For comparison of bioequivalence, the C(max) and AUC were normalised to 65kg bodyweight, and point estimates and 90% confidence intervals of the C(max) ratios, AUC ratios and ratios of the AUC in phase B normalised for clearance by the AUC in phase A (AUCR) were calculated. The three formulations were not bioequivalent based on the C(max) and AUC comparisons. CONCLUSIONS: The blood concentrations of hydralazine obtained with the tablet formulation tested in V-HeFT II were markedly lower than those obtained with the capsule formulation tested in V-HeFT I or the FDC ISDN/HYD single tablet used in A-HeFT. The apparently modest effect on survival observed in V-HeFT II could be explained in part by the poor hydralazine bioavailability of the tablet preparation used in this trial. ISDN exposures were similar in the two trials. The ISDN-hydralazine formulation used in V-HeFT II was not bioequivalent to the formulation used in V-HeFT I or to the FDC ISDN/HYD that had demonstrated a significant survival benefit in A-HeFT.

Evidence for the continued safety and tolerability of fixed-dose isosorbide dinitrate/hydralazine in patients with chronic heart failure (the extension to African-American Heart Failure Trial).

The benefits of fixed-dose combination isosorbide dinitrate plus hydralazine (ID/H) in African-Americans with heart failure (HF) were established by the African-American Heart Failure Trial (A-HeFT), which was terminated early because of a significant survival benefit of ID/H. The Extension to A-HeFT trial (X-A-HeFT), designed to make ID/H available for ethical reasons after A-HeFT termination, afforded an opportunity to further observe responsiveness and compliance with ID/H. In total 198 patients completing the A-HeFT took ID/H for an additional 209 +/- 116 days. Their age (57 +/- 13 years), cause and duration of HF, and HF medications were not different from all A-HeFT patients. New York Heart Association class at X-A-HeFT baseline was > or =III in 51% of patients versus 100% of all patients at A-HeFT baseline, remained unchanged in most patients, improved in 24%, and worsened in only 9% during X-A-HeFT. The average number of ID/H tablets taken during X-A-HeFT was 3.7 +/- 1.8 per day with compliance averaging 87 +/- 25%. The most common adverse events, headache (34%) and dizziness (16%), were less than in patients taking ID/H in A-HeFT, with only 6% discontinuations for adverse events. The 6% annualized mortality rate in X-A-HeFT was the same as for ID/H in A-HeFT. There were no statistically significant differences in baseline characteristics or outcomes in X-A-HeFT patients analyzed according to their A-HeFT randomization. In conclusion, these results confirm the good compliance, tolerability, and responsiveness, with low mortality and improved symptoms, during treatment with ID/H observed in A-HeFT.

Isosorbide dinitrate and hydralazine in a fixed-dose combination produces further regression of left ventricular remodeling in a well-treated black population with heart failure: results from A-HeFT.

BACKGROUND: Isosorbide dinitrate combined with hydralazine therapy compared with placebo in patients with heart failure resulted in a sustained increase in left ventricular (LV) ejection fraction (EF) indicative of regression of LV remodeling in the first Vasodilator-Heart Failure Trial (V-HeFT-I) in patients receiving only digoxin and diuretic. In the African-American Heart Failure Trial (A-HeFT) a fixed-dose combination resulted in a 43% reduction in mortality in 1050 black patients with heart failure already treated with recommended neurohormonal inhibiting drugs. Whether the fixed-dose combination produces a further regression of LV remodeling when added to renin-angiotensin and sympathetic inhibitors has not been documented. METHODS AND RESULTS: Echocardiograms at baseline and 6 months after randomization to placebo or a fixed-dose combination of isosorbide dinitrate/hydralazine (FDC I/H) were analyzed in 678 A-HeFT participants in a core laboratory. LVEF rose by 2.8 EF units in the FDC I/H group versus 0.8% in the control group (P < .01), LV mass index fell by 7.4 g/m2 in the FDC I/H group versus an increase of 1.4 g/m2 in the placebo group (P < .05), LV diastolic transverse diameter fell by 2.2 mm in FDC I/H and was unchanged in placebo (P < .01), and the LV systolic and diastolic sphericity indices improved in the FDC I/H group but remained unchanged in the placebo group. The mean plasma B-type natriuretic peptide (BNP) also measured in a core laboratory fell in the FDC I/H group by 39 pg/mL compared with 8 pg/mL in the placebo group (P = .05). CONCLUSIONS: A fixed-dose combination of I/H produces regression of LV remodeling when added to background therapy with renin-angiotensin and sympathetic inhibitors in black patients with heart failure. This remodeling benefit may explain at least in part the mortality reduction in A-HeFT.

Effects of ACE inhibitors or beta-blockers in patients treated with the fixed-dose combination of isosorbide dinitrate/hydralazine in the African-American Heart Failure Trial.

BACKGROUND: In the A-HeFT (African-American Heart Failure Trial), treatment of African-American patients with New York Heart Association (NYHA) class III/IV heart failure (HF) with fixed-dose combination (FDC) of isosorbide dinitrate/hydralazine (I/H) reduced mortality and morbidity and improved patient reported functional status compared with standard therapy alone. OBJECTIVE: To examine the benefit of FDC I/H in subgroups based on baseline drug therapy and to investigate whether ACE inhibitors and/or angiotensin receptor antagonists (angiotensin receptor blockers) [ARBs] or beta-adrenoceptor antagonists (beta-blockers) provided additional benefit in FDC I/H-treated African-American patients with HF. STUDY DESIGN: The A-HeFT was a double-blind, placebo-controlled study enrolling 1050 patients stabilized on optimal HF therapies and with NYHA class III/IV HF with systolic dysfunction conducted during the years 2001-4 with up to 18 months follow-up. The primary endpoint was a composite of mortality, first HF hospitalization, and improvement of quality of life at 6 months. Secondary endpoints included mortality, hospitalizations, and change in quality of life. Prospective Kaplan-Meier survival analyses were used for differences between FDC I/H and placebo groups and retrospective analyses were conducted within FDC I/H-treated and placebo groups. RESULTS: Subgroup analysis for mortality, event-free survival (death or first HF hospitalization), and HF hospitalization showed that FDC I/H, compared with placebo, was effective with or without ACE inhibitors or beta-blockers or other standard medications with all-point estimates favoring the FDC I/H group. Within the placebo-treated group, beta-blockers or ACE inhibitors and/or ARBs were efficacious in improving survival (hazard ratio [HR] 0.33; p<0.0001 for [beta]-blocker use and HR 0.39; p=0.01 for ACE inhibitor and/or ARB use). However, within the FDC I/H-treated group, use of beta-blockers, but not ACE inhibitors and/or ARBs, provided additional significant benefit for survival (HR 0.44; p=0.029 and HR 0.60; p=0.34, respectively), event-free survival (HR 0.62; p=0.034 and HR 0.72; p=0.29, respectively) and the composite score of death, HF hospitalization and change in quality of life (p=0.016 and p=0.13, respectively). CONCLUSION: Based on the analysis of baseline medication use in the A-HeFT, FDC I/H was superior to placebo with or without beta-blockers or ACE inhibitor. However, beta-blockers but not ACE inhibitors and/or ARBs provided additional significant benefit in African-Americans with HF treated with FDC I/H. These analyses are hypotheses generating and their confirmation in clinical trials needs to be considered.

Cost-effectiveness of fixed-dose combination of isosorbide dinitrate and hydralazine therapy for blacks with heart failure.

BACKGROUND: Fixed-dose combination of isosorbide dinitrate/hydralazine (ISDN/HYD) improved clinical outcomes in the African-American Heart Failure Trial (A-HeFT). We assessed the resource use, costs of care, and cost-effectiveness of ISDN/HYD therapy in the A-HeFT trial population. METHODS AND RESULTS: We obtained resource use data from A-HeFT, assigning costs through the use of US federal sources. Excluding indirect costs, we summarized the within-trial experience and modeled cost-effectiveness over extended time horizons, including a US societal lifetime reference case. During the mean trial follow-up of 12.8 months, the ISDN/HYD group incurred fewer heart failure-related hospitalizations (0.33 versus 0.47 per subject; P=0.002) and shorter mean hospital stays (6.7 versus 7.9 days; P=0.006). When study drug costs were excluded, both heart failure-related and total healthcare costs were lower in the ISDN/HYD group (mean per-subject heart failure-related costs, 5997 dollars versus 9144 dollars; P=0.04; mean per-subject total healthcare costs, 15,384 dollars versus 19,728 dollars; P=0.03). With an average daily drug cost of 6.38 dollars, ISDN/HYD therapy was dominant (reduced costs and improved outcomes) over the trial duration. Assuming that no additional benefits accrue beyond the trial, we project the cost-effectiveness of ISDN/HYD therapy using heart failure-related costs to be 16,600 dollars/life-year at 2 years after enrollment, 37,100 dollars/life-year at 5 years, and 41,800 dollars/life-year over lifetime (reference case). CONCLUSIONS: ISDN/HYD therapy, previously shown to improve clinical outcomes, also reduced resource use and costs in A-HeFT, primarily because of a large reduction in hospitalizations. Long-term use of ISDN/HYD therapy should be associated with a favorable cost-effectiveness profile in this population.

The African-American Heart Failure Trial: background, rationale and significance.

New treatments have improved outcomes in heart failure (HF), but applicability of these advances may be limited in African Americans. Analysis of previous trials has shown that a combination of hydralazine (H) plus isosorbide dinitrate (ISDN) may be especially beneficial in African Americans with HF. The African American Heart Failure Trial (A-HeFT) is a double-blind, randomized, and placebo-controlled trial in African American patients with stable NYHA Class III-IV HF while on standard therapy. Randomization to addition of BiDil, a fixed combination of H+ISDN, or placebo, will be stratified for beta-blocker usage, and all patients will be treated and followed until the last patient entered has completed six months of follow-up. The primary efficacy endpoint will be a composite score including quality of life, deaths, and hospitalizations for HF. At least 600 patients will be randomized. The first patient was randomized in June, 2001. Besides additional testing of H+ISDN in HF, A-HeFT will be the first HF trial aimed at a subgroup of African American patients, as well as the first to use a new composite HF score as its primary efficacy endpoint.

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.

Dysfunctional corin i555(p568) allele is associated with impaired brain natriuretic peptide processing and adverse outcomes in blacks with systolic heart failure: results from the Genetic Risk Assessment in Heart Failure substudy.

BACKGROUND: Corin, a transmembrane serine protease expressed in cardiomyocytes, cleaves pro-atrial natriuretic peptide and pro-brain natriuretic peptide (BNP) into biologically active peptide hormones. The minor corin I555(P568) allele, defined by the T555I and Q568P mutations, is common in persons of African ancestry and associated with increased risk for hypertension and cardiac concentric hypertrophy. The corin gene product containing the T555I and Q568P mutations has significantly reduced natriuretic peptide processing capacity. We hypothesized that the corin I555(P568) allele would be associated with adverse outcomes and impaired BNP processing in blacks with systolic heart failure. METHODS AND RESULTS: This is a retrospective study of 354 subjects in the African American Heart Failure Trial Genetic Risk Assessment in Heart Failure substudy. In the corin variant group (n=50) compared with corin nonvariant group (n=300), BNP-32 (amino acids 77 to 108) was lower (190 pg/mL versus 340 pg/mL, P=0.007), but the ratio of unprocessed BNP(1 to 108)/processed BNP-32 was significantly higher (P=0.05). Stratified analyses were conducted because of evidence of significant interaction between the corin I555(P568) allele and treatment assignment. In the placebo arm, multivariable analysis demonstrated that the corin I555(P568) allele was associated with increased risk for death or heart failure hospitalization (relative risk 3.49; 95% CI, 1.45 to 8.39; P=0.005); however, in the treatment arm (fixed-dose combination isosorbide-dinitrate/hydralazine), the corin I555(P568) allele was not associated with adverse outcomes. CONCLUSIONS: We have identified a pharmacogenomic interaction in blacks with systolic heart failure. The corin I555(P568) allele is associated with an increased risk for death or heart failure hospitalization in patients receiving standard neurohormonal blockade, but the addition of fixed-dose combination isosorbide-dinitrate/hydralazine ameliorates this risk. A plausible mechanism for this pharmacogenomic interaction is the impaired processing of BNP in carriers of the corin I555(P568) allele as compared with noncarriers.

Influence of blood pressure on the effectiveness of a fixed-dose combination of isosorbide dinitrate and hydralazine in the African-American Heart Failure Trial.

OBJECTIVES: This study sought to assess the effect of baseline systolic blood pressure (SBP) and changes in SBP on the effectiveness of treatment with fixed-dose combination of isosorbide dinitrate and hydralazine (FDC I/H) in patients with heart failure (HF). BACKGROUND: Low SBP is a risk factor for adverse outcomes in patients with HF. However, FDC I/H lowered SBP in the A-HeFT (African-American Heart Failure Trial) and yet prolonged survival. Whether blood pressure (BP) lowering is critical to the efficacy of FDC I/H and whether a low BP limits its effectiveness is unclear. METHODS: The effects of FDC I/H on SBP and on mortality and hospitalization were compared in patients with a low or high baseline SBP using multivariable Cox regression models. The interaction between the effect of treatment and baseline SBP was examined. RESULTS: Mean +/- SD baseline SBP in all of the patients was 126 +/- 18 mm Hg. Patients with baseline SBP equal to or below the median (126 mm Hg) had features of more severe HF. Baseline SBP equal to or below the median was an independent risk factor for death (hazard ratio [HR] 2.09; 95% confidence interval [CI] 1.02 to 4.29) or first hospitalization for HF (HR 1.66; 95% CI 1.18 to 2.34). The FDC I/H treatment reduced BP in patients with SBP above the median but not in patients with SBP below 126 mm Hg. The FDC I/H treatment was associated with a similar decrease in mortality or hospitalization for HF in patients with SBP below the median and above the median. The effects of FDC I/H on mortality alone were also similar. CONCLUSIONS: In A-HeFT, patients with lower SBP had a greater risk but a similar relative benefit from the use of FDC I/H as those with higher SBP. The FDC I/H treatment did not reduce SBP in patients with low SBP. An asymptomatic low SBP should not be considered a contraindication to use of FDC I/H in patients with HF.

Aldosterone synthase promoter polymorphism predicts outcome in African Americans with heart failure: results from the A-HeFT Trial.

OBJECTIVES: We sought to evaluate the effect of the aldosterone synthase promoter polymorphism on heart failure outcomes for subjects in the African American Heart Failure Trial (A-HeFT). BACKGROUND: Genetic heterogeneity modulates clinical outcomes in subjects with heart failure (HF); however, little data exist in African American populations. A common polymorphism exists in the promoter region of the aldosterone synthase gene (CYP11B2) at position -344 (T/C). The -344C allele, associated with higher aldosterone synthase activity, has been linked to hypertension; however, its impact on outcomes in HF is unknown. METHODS: A total of 354 subjects from A-HeFT participated in the GRAHF (Genetic Risk Assessment of Heart Failure in African Americans) substudy and were genotyped for the aldosterone synthase polymorphism. Patients were followed prospectively, and event-free survival (freedom from death and HF hospitalization) compared by CYP11B2 genotype. RESULTS: Of the cohort, 218 patients were TT, 114 CT, and 22 patients were CC. Baseline etiology, blood pressure, and functional class were not significantly different among the 3 cohorts. The C allele was associated with significantly poorer HF hospitalization-free survival with the best survival among TT subjects, intermediate for heterozygotes, and the poorest for CC homozygotes (p = 0.018), and a higher rate of death (% death TT/TC/CC = 1.8/3.5/18.2, p = 0.001). The TT genotype, more prevalent in blacks, was associated with greater impact of fixed combination of isosorbide dinitrate and hydralazine on the primary composite end point (p = 0.01). CONCLUSIONS: The aldosterone synthase promoter -344C allele linked to higher aldosterone levels is associated with poorer event-free survival in blacks with HF. The role of aldosterone receptor antagonists in diminishing this apparent genetic risk remains to be explored.

Outcomes by gender in the African-American Heart Failure Trial.

OBJECTIVES: Previous trials testing isosorbide dinitrate/hydralazine (I/H) were performed in all-male study cohorts, and thus the efficacy of I/H in women was unknown; 40% of the A-HeFT (African-American Heart Failure Trial) cohort were women. We therefore compared outcomes by gender and treatment. BACKGROUND: Fixed-dose combined I/H significantly reduced mortality and heart failure hospitalizations and improved quality of life in 1,050 black patients with heart failure treated with background neurohormonal blockade. Previous trials testing I/H were done in all-male study cohorts, and thus the efficacy of I/H in women was unknown. METHODS: Baseline characteristics and medications were compared between men and women by I/H and placebo treatment. Survival, time to first heart failure hospitalization, change in quality of life, and event-free survival were compared by gender and treatment. RESULTS: At baseline, women had lower hemoglobin and creatinine levels; less renal insufficiency; and higher body mass indexes, diabetes prevalence, and systolic blood pressures; but worse quality of life scores. All-cause mortality was lower in women than in men treated with I/H but without significant treatment interaction by gender. The primary composite score, which weighted mortality, first heart failure hospitalization, and change in quality of life at 6 months, was similarly improved by I/H in men and women. First heart failure hospitalization and event-free survival (time to death or first heart failure hospitalization) were similarly improved in both genders. CONCLUSIONS: Fixed-dose I/H improved heart failure outcomes in both men and women in A-HeFT. The I/H significantly improved the primary composite score and event-free survival as well as reduced the risk of first heart failure hospitalizations similarly in both genders. The I/H had a slightly greater mortality benefit in women, but without a significant treatment interaction by gender.

The effects of yohimbine plus L-arginine glutamate on sexual arousal in postmenopausal women with sexual arousal disorder.

This study examined the effects of the nitric oxide-precursor L-arginine combined with the alpha 2-blocker yohimbine on subjective and physiological sexual arousal in postmenopausal women with Female Sexual Arousal Disorder. Twenty-four women participated in three treatment sessions in which self-report and physiological (vaginal photoplethysmograph) sexual responses to erotic stimuli were measured following treatment with either L-arginine glutamate (6 g) plus yohimbine HCl (6 mg), yohimbine alone (6 mg), or placebo, using a randomized, double-blind, three-way cross-over design. Sexual responses were measured at approximately 30, 60, and 90 min postdrug administration. The combined oral administration of L-arginine glutamate and yohimbine substantially increased vaginal pulse amplitude responses to the erotic film at 60 min postdrug administration compared with placebo. Subjective reports of sexual arousal were significantly increased with exposure to the erotic stimuli but did not differ significantly between treatment groups.

Efficacy and safety of a novel combination of L-arginine glutamate and yohimbine hydrochloride: a new oral therapy for erectile dysfunction.

PURPOSE: The goal of this double-blind, placebo-controlled, three-way crossover, randomized clinical trial was to compare the efficacy and safety of the combination of 6g of L-arginine glutamate and 6 mg of yohimbine hydrochloride (AY) with that of 6 mg of yohimbine hydrochloride (YP) alone and that of placebo (PP) alone, for the treatment of erectile dysfunction (ED). MATERIALS AND METHODS: Forty-five patients were included in this study. During each of the 2-week, crossover periods, drug was administered orally, one to two hours before intended sexual intercourse. The primary endpoint was change in the Erectile Function Domain score of the International Index of Erectile Function (IIEF). The secondary endpoints were patient and investigator assessments of treatment success. RESULTS: At the end of each treatment period, the Erectile Function Domain scores for AY, YP and PP were 17.2+/-7.17, 15.4+/-6.49 and 14.1+/-6.56, respectively. The difference between AY and PP was statistically significant (p=0.006). When stratified according to baseline scores over 14, those patients with mild to moderate MED had a better Erectile Function Domain response to treatment (AY=22.2+/-4.99, YP=18.2+/-5.59, PP=16.9+/-6.91, respectively) than those with scores 14 and below (AY=12.4+/-5.48, YP=12.7+/-6.25, PP=11.4+/-5.02, respectively). Investigators' and patients' assessment of efficacy was significantly improved by YP over PP. CONCLUSIONS: This pilot study shows that the on-demand oral administration of the L-arginine glutamate 6g and 6 mg yohimbine combination is effective in improving erectile function in patients with mild to moderate ED. It appears to be a promising addition to first-line therapy for ED.