Effect of ivabradine on recurrent hospitalization for worsening heart failure in patients with chronic systolic heart failure: the SHIFT Study

AIMS

We explored the effect of treatment with ivabradine, a pure heart rate-slowing agent, on recurrent hospitalizations for worsening heart failure (HF) in the SHIFT trial.

METHODS AND RESULTS

SHIFT was a double-blind clinical trial in which 6505 patients with moderate-to-severe HF and left ventricular systolic dysfunction, all of whom had been hospitalized for HF during the preceding year, were randomized to ivabradine or to placebo on a background of guideline-recommended HF therapy (including maximized β-blockade). In total, 1186 patients experienced at least one additional HF hospitalization during the study, 472 suffered at least two, and 218 suffered at least 3. Patients with additional HF hospitalizations had more severe disease than those without. Ivabradine was associated with fewer total HF hospitalizations [902 vs. 1211 events with placebo; incidence rate ratio, 0.75, 95% confidence interval (CI), 0.65-0.87, P = 0.0002] during the 22.9-month median follow-up. Ivabradine-treated patients evidenced lower risk for a second or third additional HF hospitalization [hazard ratio (HR): 0.66, 95% CI, 0.55-0.79, P < 0.001 and HR: 0.71, 95% CI, 0.54-0.93, P = 0.012, respectively]. Similar observations were made for all-cause and cardiovascular hospitalizations.

CONCLUSION

Treatment with ivabradine, on a background of guidelines-based HF therapy, is associated with a substantial reduction in the likelihood of recurrent hospitalizations for worsening HF. This benefit can be expected to improve the quality of life and to substantially reduce health-care costs.

Myocardial Revascularization in New York State: Variations in the PCI-to-CABG Ratio and Their Implications

BACKGROUND

During the past 2 decades, percutaneous coronary intervention (PCI) has increased dramatically compared with coronary artery bypass grafting (CABG) for patients with coronary artery disease. However, although the evidence available to all practitioners is similar, the relative distribution of PCI and CABG appears to differ among hospitals and regions.

METHODS AND RESULTS

We reviewed the published data from the mandatory New York State Department of Health annual cardiac procedure reports issued from 1994 through 2008 to define trends in PCI and CABG utilization in New York and to compare the PCI/CABG ratios in the metropolitan area to the remainder of the State. During this 15-year interval, the procedure volume changes for CABG, for all cardiac surgeries, for non-CABG cardiac surgeries, and for PCI for New York State were -40%, -20%, +17.5%, and +253%, respectively; for the Manhattan programs, the changes were similar as follows: -61%, -23%, +14%, and +284%. The average PCI/CABG ratio in New York State increased from 1.12 in 1994 to 5.14 in 2008; however, in Manhattan, the average PCI/CABG ratio increased from 1.19 to 8.04 (2008 range: 3.78 to 16.2). The 2008 PCI/CABG ratios of the Manhattan programs were higher than the ratios for New York City programs outside Manhattan, in Long Island, in the northern counties contiguous to New York City, and in the rest of New York State; their averages were 5.84, 5.38, 3.31, and 3.24, respectively. In Manhattan, a patient had a 56% greater chance of receiving PCI than CABG as compared with the rest of New York State; in one Manhattan program, the likelihood was 215% higher.

CONCLUSIONS

There are substantial regional and statewide differences in the utilization of PCI versus CABG among cardiac centers in New York, possibly related to patient characteristics, physician biases, and hospital culture. Understanding these disparities may facilitate the selection of the most appropriate, effective, and evidence-based revascularization strategy. (J Am Heart Assoc. 2012;1:e001446 doi: 10.1161/JAHA.112.001446.).

Effects of selective heart rate reduction with ivabradine on left ventricular remodelling and function: results from the SHIFT echocardiography substudy

AIMS

The SHIFT echocardiographic substudy evaluated the effects of ivabradine on left ventricular (LV) remodelling in heart failure (HF).

METHODS AND RESULTS

Eligible patients had chronic HF and systolic dysfunction [LV ejection fraction (LVEF) ≤35%], were in sinus rhythm, and had resting heart rate ≥70 bpm. Patients were randomly allocated to ivabradine or placebo, superimposed on background therapy for HF. Complete echocardiographic data at baseline and 8 months were available for 411 patients (ivabradine 208, placebo 203). Treatment with ivabradine reduced LVESVI (primary substudy endpoint) vs. placebo [-7.0 ± 16.3 vs. -0.9 ± 17.1 mL/m(2); difference (SE), -5.8 (1.6), 95% CI -8.8 to -2.7, P< 0.001]. The reduction in LVESVI was independent of beta-blocker use, HF aetiology, and baseline LVEF. Ivabradine also improved LV end-diastolic volume index (-7.9 ± 18.9 vs. -1.8 ± 19.0 mL/m(2), P= 0.002) and LVEF (+2.4 ± 7.7 vs. -0.1 ± 8.0%, P< 0.001). The incidence of the SHIFT primary composite outcome (cardiovascular mortality or hospitalization for worsening HF) was higher in patients with LVESVI above the median (59 mL/m2) at baseline (HR 1.62, 95% CI 1.03-2.56, P= 0.04). Patients with the largest relative reductions in LVESVI had the lowest event rates.

CONCLUSION

Ivabradine reverses cardiac remodelling in patients with HF and LV systolic dysfunction.

Heart rate as a risk factor in chronic heart failure (SHIFT): the association between heart rate and outcomes in a randomised placebo-controlled trial

BACKGROUND

Raised resting heart rate is a marker of cardiovascular risk. We postulated that heart rate is also a risk factor for cardiovascular events in heart failure. In the SHIFT trial, patients with chronic heart failure were treated with the selective heart-rate-lowering agent ivabradine. We aimed to test our hypothesis by investigating the association between heart rate and events in this patient population.

METHODS

We analysed cardiovascular outcomes in the placebo (n=3264) and ivabradine groups (n=3241) of this randomised trial, divided by quintiles of baseline heart rate in the placebo group. The primary composite endpoint was cardiovascular death or hospital admission for worsening heart failure. In the ivabradine group, heart rate achieved at 28 days was also analysed in relation to subsequent outcomes. Analysis adjusted to change in heart rate was used to study heart-rate reduction as mechanism for risk reduction by ivabradine directly.

FINDINGS

In the placebo group, patients with the highest heart rates (>or=87 beats per min [bpm], n=682, 286 events) were at more than two-fold higher risk for the primary composite endpoint than were patients with the lowest heart rates (70 to <72 bpm, n=461, 92 events; hazard ratio [HR] 2.34, 95% CI 1.84-2.98, p<0.0001). Risk of primary composite endpoint events increased by 3% with every beat increase from baseline heart rate and 16% for every 5-bpm increase. In the ivabradine group, there was a direct association between heart rate achieved at 28 days and subsequent cardiac outcomes. Patients with heart rates lower than 60 bpm at 28 days on treatment had fewer primary composite endpoint events during the study (n=1192; event rate 17.4%, 95% CI 15.3-19.6) than did patients with higher heart rates. The effect of ivabradine is accounted for by heart-rate reduction, as shown by the neutralisation of the treatment effect after adjustment for change of heart rate at 28 days (HR 0.95, 0.85-1.06, p=0.352).

INTERPRETATION

Our analysis confirms that high heart rate is a risk factor in heart failure. Selective lowering of heart rates with ivabradine improves cardiovascular outcomes. Heart rate is an important target for treatment of heart failure.

FUNDING

Servier, France.

Ivabradine and outcomes in chronic heart failure (SHIFT): a randomised placebo-controlled study

BACKGROUND

Chronic heart failure is associated with high mortality and morbidity. Raised resting heart rate is a risk factor for adverse outcomes. We aimed to assess the effect of heart-rate reduction by the selective sinus-node inhibitor ivabradine on outcomes in heart failure.

METHODS

Patients were eligible for participation in this randomised, double-blind, placebo-controlled, parallel-group study if they had symptomatic heart failure and a left-ventricular ejection fraction of 35% or lower, were in sinus rhythm with heart rate 70 beats per min or higher, had been admitted to hospital for heart failure within the previous year, and were on stable background treatment including a β blocker if tolerated. Patients were randomly assigned by computer-generated allocation schedule to ivabradine titrated to a maximum of 7.5 mg twice daily or matching placebo. Patients and investigators were masked to treatment allocation. The primary endpoint was the composite of cardiovascular death or hospital admission for worsening heart failure. Analysis was by intention to treat. This trial is registered, number ISRCTN70429960.

FINDINGS

6558 patients were randomly assigned to treatment groups (3268 ivabradine, 3290 placebo). Data were available for analysis for 3241 patients in the ivabradine group and 3264 patients allocated placebo. Median follow-up was 22.9 (IQR 18-28) months. 793 (24%) patients in the ivabradine group and 937 (29%) of those taking placebo had a primary endpoint event (HR 0.82, 95% CI 0.75-0.90, p<0.0001). The effects were driven mainly by hospital admissions for worsening heart failure (672 [21%] placebo vs 514 [16%] ivabradine; HR 0.74, 0.66-0.83; p<0.0001) and deaths due to heart failure (151 [5%] vs 113 [3%]; HR 0.74, 0.58-0.94, p=0.014). Fewer serious adverse events occurred in the ivabradine group (3388 events) than in the placebo group (3847; p=0.025). 150 (5%) of ivabradine patients had symptomatic bradycardia compared with 32 (1%) of the placebo group (p<0.0001). Visual side-effects (phosphenes) were reported by 89 (3%) of patients on ivabradine and 17 (1%) on placebo (p<0.0001).

INTERPRETATION

Our results support the importance of heart-rate reduction with ivabradine for improvement of clinical outcomes in heart failure and confirm the important role of heart rate in the pathophysiology of this disorder.

FUNDING

Servier, France.

Efficacy of ivabradine, a selective I(f) inhibitor, in patients with chronic stable angina pectoris and diabetes mellitus

Ivabradine is a specific heart rate-lowering antianginal agent that was evaluated in a clinical development program involving approximately 3,000 patients with stable coronary artery disease, most with angina pectoris. We analyzed the pharmacokinetics, efficacy (evaluated by exercise tolerance testing), safety, and effects on glucose metabolism of ivabradine in patients with diabetes mellitus (DM) in this program. Most analyses included data from 535 patients with DM, approximately 18% of the overall patient sample. Patients with DM were older, more likely to be women, and more likely to have more severe angina pectoris than patients without DM. The pharmacokinetics of ivabradine did not differ in patients with DM versus those without DM. A reduction in the heart rate at rest with ivabradine was similar in those with (15.2%) and without (15.7%) DM. At baseline, the exercise capacity tended to be lower in the patients with DM, but the improvements in most exercise tolerance measures with ivabradine treatment were similar in patients with and without DM. No special safety concerns were associated with ivabradine in those with DM. The rates of sinus bradycardia and visual disturbances, known to be related to the action of ivabradine, showed no relative increase in the patients with DM. Ivabradine treatment was not associated with adverse effects on glucose metabolism. In conclusion, ivabradine was effective in preventing angina in patients with DM and was not associated with particular safety concerns or adverse effects on glucose metabolism. Ivabradine represents an attractive alternative to beta blockers in patients with stable angina pectoris and DM.

Anxiety and cardiovascular symptoms: the modulating role of insomnia

BACKGROUND

Anxiety and insomnia are associated with cardiovascular (CV) symptoms. We assessed whether the relation between anxiety and CV symptoms is modulated by insomnia.

METHODS

Independently living women (n = 1,440; mean age = 59.36 +/- 6.53 years) were recruited by cluster sampling technique. We obtained data on demographic characteristics, health beliefs, access to health care, CV symptoms, sleep, stress and anxiety levels.

RESULTS

Overall, 56% of the sample reported insomnia; 46% reported CV symptoms, and 54% were highly anxious. There was a greater likelihood for highly anxious women and those experiencing insomnia to report CV symptoms (r(s) = 0.31* and r(s) = 0.32*, respectively). In logistic regression analysis, the adjusted odds ratios for reporting CV symptoms were 1.39 for patients with insomnia and 2.79 for those with anxiety. With control for insomnia, we observed a 3-fold reduction in the magnitude of the association between anxiety and CV symptoms (r(p) = 0.09*). Stepwise adjustments for sociodemographic factors, CV risk markers, and factors anchoring health beliefs and access to health care showed lesser impact on the relationships. With simultaneous control for those covariates, the correlation was r(p) = 0.13*; * p < 0.01.

CONCLUSION

The association of CV symptoms with anxiety is partly accounted for by insomnia.

Efficacy of I(f) inhibition with ivabradine in different subpopulations with stable angina pectoris

OBJECTIVES

The antianginal and anti-ischemic efficacy of ivabradine has been demonstrated in large-scale trials. Pooling trial data allowed for subpopulation analyses of ivabradine's antianginal efficacy.

METHODS

Data on the frequency of angina attacks, short-acting nitrate consumption, and heart rate were pooled from 5 randomized trials in patients with stable angina pectoris receiving 5, 7.5, or 10 mg of ivabradine b.i.d. for 3 or 4 months. The subpopulations were defined according to age, sex, disease characteristics, and comorbidities (severity of angina, history of myocardial infarction, cerebrovascular disease, revascularization status, diabetes, asthma/chronic obstructive pulmonary disease, or peripheral vascular disease).

RESULTS

Efficacy data were available for 2,425 patients (full analysis set), in whom ivabradine reduced the frequency of diary-based angina attacks by 59.4% and nitrate consumption by 53.7%. All subpopulations experienced 51-70% reductions in the frequency of angina attacks, with similar reductions for the other parameters studied. Ivabradine's efficacy was maintained in the presence of different comorbidities. In the safety set, ivabradine reduced heart rate by 14.5%. Ivabradine had a good safety and tolerability profile in all the subpopulations assessed.

CONCLUSIONS

The antianginal efficacy of ivabradine was consistent across all the subpopulations analyzed, independent of the severity of angina and the presence of a comorbidity.

Fibronectin gene expression in aortic regurgitation: relative roles of mitogen-activated protein kinases

OBJECTIVES

In aortic regurgitation (AR), fibronectin (FN) expression is upregulated. This study sought to determine signal transduction pathways involved in upregulation of FN expression in AR.

METHODS

Cardiac fibroblasts (CF) from rabbits with surgically induced AR and matched controls (NL) were cultured and assayed for FN expression and kinase activity with and without inhibitors of kinases JNK, p38 mitogen-activated protein kinase (MAPK) and extracellular response kinase (ERK). NL CF also were subjected to cyclic strain mimicking AR for 24 h in culture with and without inhibitors.

RESULTS

AR CF exhibited 2.9-fold greater c-Jun phosphorylation (p < 0.01) and 1.5- to 2-fold greater ATF2 phosphorylation (p < 0.05-0.01) than NL. JNK and p38MAPK inhibition reduced c-Jun and ATF2 phosphorylation to NL; ERK inhibition had no effect. FN mRNA expression was similar in pattern to kinase activities. Cyclic strain in NL CF increased c-Jun phosphorylation 2-fold versus unstrained controls (p < 0.005). This was suppressed by inhibition of JNK but not p38MAPK.

CONCLUSION

FN expression in response to the acute mechanical strain resembling AR is upregulated primarily via JNK. However, in chronic AR both JNK and p38MAPK are involved. These signaling pathways represent potential therapeutic targets for normalizing extracellular matrix (ECM) composition and contractile force transmission, believed to be related to ECM composition/organization, in AR.

Unconventional end points in cardiovascular clinical trials: should we be moving away from morbidity and mortality?

BACKGROUND

Mortality and irreversible or major morbid events are the end points conventionally chosen for cardiovascular clinical trials because they are considered to reflect the effects of intervention on the natural history of disease. Other end points are now being considered and implemented because of the recognized limitations associated with using mortality and morbidity as the sole measures of therapeutic efficacy.

METHODS AND RESULTS

This article reflects the discussion and recommendations regarding nontraditional end points for cardiovascular trials generated from a meeting of clinical trial experts convened to discuss this issue. Less common end points that have been used in cardiovascular clinical trials include composite clinical scores integrating measures of quality of life with mortality and morbidity or using the function of vital organs as end points. Appropriate measurement and applications of such end points is controversial.

CONCLUSIONS

More experience is needed in applying and analyzing results with these nontraditional end points to enable their optimal use in clinical trials in cardiology, but such approaches have the potential to redress many of the conceptual and actual deficiencies inherent in conventional measures of outcome.

Acceptability and psychometric properties of the Minnesota Living With Heart Failure Questionnaire among patients undergoing heart valve surgery: validation and comparison with SF-36

BACKGROUND

Health-related quality of life (HQOL) enhancement is a major objective of valvular surgery (VS), but assessments have been limited primarily to generic measures that may not be optimally responsive to intervention. Disease-specific instruments have been used in heart failure (HF), commonly associated with valve disease, but have been neither validated nor routinely applied among patients undergoing VS.

METHODS AND RESULTS

We administered the Minnesota Living with Heart Failure (MLHFQ) and SF-36 questionnaires preoperatively (T(0)) to 50 patients undergoing VS and at 1 (T(1)) and 6 months (T(2)) after VS. Performance of MLHFQ was evaluated and compared with SF-36. MLHFQ completion rates were >98% (NS vs. SF-36); Cronbach's alpha was > or = 0.9 (total score, dimensions), supporting internal reliability. Confirmatory factor analysis verified good model fit for physical/emotional domain items (relative chi-squares < 3.0, critical ratios > 2.0, both instruments), supporting structural validity. Spearman coefficients correlating MLHFQ with parallel SF-36 domains were moderate to high (0.6-0.9; P < or = .001: T(0)-T(2)), supporting convergent validity. Baseline HQOL was poorest in patients with HF (P < or = .05 [both instruments]), supporting criterion validity. Responsiveness (proportional HQOL change scores: T(0) vs. T(2)) to VS was greater with MLHFQ vs. SF-36 (P < or = .002).

CONCLUSIONS

Among patients undergoing VS, the MLHFQ is highly acceptable and maintains good psychometric properties, comparing favorably with SF-36. These findings suggest its utility for measuring disease-specific HQOL changes after VS.