Influence of global region on outcomes in heart failure β-blocker trials

Contemporary Use and Implications of Beta-Blockers in Patients With HFmrEF or HFpEF: The DELIVER Trial

BACKGROUND

Although beta-blockers are not recommended for the treatment of heart failure with preserved ejection fraction (HFpEF) according to the latest European Society of Cardiology and American Heart Association/American College of Cardiology/Heart Failure Society of America guidelines, these therapies remain commonly used for comorbidity management. There has been concern that beta-blockers may adversely influence clinical outcomes by limiting chronotropic response in HFpEF.

OBJECTIVES

This study sought to examine the contemporary use and implications of beta-blockers in patients with heart failure with mildly reduced ejection fraction (HFmrEF) or HFpEF.

METHODS

In the DELIVER (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure) trial, a total of 6,263 patients with symptomatic heart failure (HF) with a left ventricular ejection fraction (LVEF) >40% were randomized to dapagliflozin or placebo across 20 countries. In this prespecified analysis, efficacy and safety outcomes were examined according to beta-blocker use at randomization. The primary outcome was cardiovascular death or worsening HF.

RESULTS

Overall, beta-blockers were used in 5,177 patients (83%), with wide variation by geographic region. Beta-blocker use was associated with a lower risk of the primary outcome in covariate-adjusted models (HR: 0.70; 95% CI: 0.60-0.83). Dapagliflozin consistently reduced the risk of the primary outcome in patients taking beta-blockers (HR: 0.82; 95% CI: 0.72-0.94) and in patients not taking beta-blockers (HR: 0.79; 95% CI: 0.61-1.03; Pinteraction = 0.85), with similar findings for key secondary endpoints. Adverse events were balanced between patients randomized to dapagliflozin and placebo, regardless of background beta-blocker use.

CONCLUSIONS

In patients with HFmrEF or HFpEF who were enrolled in DELIVER, 4 out of 5 participants were treated with a beta-blocker. Beta-blocker use was not associated with a higher risk of worsening HF or cardiovascular death. Dapagliflozin consistently and safely reduced clinical events, irrespective of background beta-blocker use. (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure [DELIVER]; NCT03619213).

Lower doses of carvedilol in Japanese heart failure patients with reduced ejection fraction could show the potential to be non-inferior to higher doses in US patients: An international collaborative observational study

The Japanese national guidelines recommend significantly lower doses of carvedilol for heart failure with reduced ejection fraction (HFrEF) management than the US guidelines. Using real-world data, we determined whether initial and target doses of carvedilol in Japanese patients (JPNs) differ from those in US patients (USPs), especially in Asian Americans (ASA) and Caucasians (CA), and investigated differences in outcomes. We collected data from the electronic medical records, including demographics, carvedilol dosing, tolerability, cardiac functional indicators like EF, cardiovascular events including all-cause deaths, and laboratory values from the University of California, San Diego Health and Osaka University. JPNs had significantly lower doses (mg/day) of carvedilol initiation (66 USPs composed of 38 CAs and 28 ASAs, 17.1±16.2; 93 JPNs, 4.3±4.2, p<0.001) and one year after initiation (33.0±21.8; 11.2±6.5, p<0.001), and a significantly lower relative rate (RR) of dose discontinuation and reduction than USPs (RR: 0.406, 95% confidence interval (CI): 0.181-0.911, p<0.05). CAs showed the highest reduction rate (0.184), and ASAs had the highest discontinuation rate (0.107). A slight mean difference with narrow 95% CI ranges straddling zero was observed between the two regions in the change from the baseline of each cardiac functional indicator (LVEF, -0.68 [-5.49-4.12]; LVDd, -0.55 [-3.24-2.15]; LVDd index, -0.25 [-1.92-1.43]; LVDs, -0.03 [-3.84-3.90]; LVDs index, -0.04 [-2.38-2.30]; heart rate, 1.62 [-3.07-6.32]). The event-free survival showed no difference (p = 0.172) among the races. Conclusively, despite JPNs exhibiting markedly lower carvedilol doses, their dose effectiveness has the potential to be non-inferior to that in USPs. Dose de-escalation, not discontinuation, could be an option in some Asian and ASA HFrEF patients intolerable to high doses of carvedilol.

Geographic differences in patients with acute myocardial infarction in the PARADISE-MI trial

AIM

The globalization of clinical trials has highlighted geographic differences in patient characteristics, treatments, and outcomes. We examined these differences in PARADISE-MI.

METHODS AND RESULTS

Overall, 23.0% were randomized in Eastern Europe/Russia, 17.5% in Western Europe, 12.2% in Southern Europe, 10.1% in Northern Europe, 12.0% in Latin America (LA), 9.3% in North America (NA), 10.0% in East/South-East Asia and 5.8% in South Asia (SA). Those from Asia, particularly SA, were different from patients enrolled in the other regions, being younger and thinner. They also differed in terms of comorbidities (high prevalence of diabetes and low prevalence of atrial fibrillation), type of myocardial infarction (more often ST-elevation myocardial infarction), and treatment (low rate of primary percutaneous coronary intervention). By contrast, patients from LA did not differ meaningfully from those randomized in Europe or NA. Use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (34.8%) and beta-blockers (65.5%) was low in SA, whereas mineralocorticoid receptor antagonist use was lowest in NA (22%) and highest in Eastern Europe/Russia (53%). Rates of the primary composite outcome of cardiovascular death or incident heart failure varied two-fold among regions, with the lowest rate in SA (4.6/100 person-years) and the highest in LA (9.2/100 person-years). Rates of incident heart failure varied almost six-fold among regions, with the lowest rate in SA (1.0/100 person-years) and the highest in Northern Europe (5.9/100 person-years). The effect of sacubitril/valsartan was not modified by region.

CONCLUSION

In PARADISE-MI, there were substantial regional differences in patient characteristics, treatments and outcomes. Although the generalizability of these findings to a 'real-world' unselected population may be limited, these findings underscore the importance of considering both regional and within-region differences when designing global clinical trials.

Regional variation of effects of new antidiabetic medications in cardiovascular outcome trials

BACKGROUND

In international trials, glucagon-like protein-1 receptor agonists (GLP-1RAs) and sodium-glucose cotransporter-2 inhibitors (SGLT2Is) were effective in improving cardiovascular (CV) outcomes.

METHODS

We assessed the effect of GLP-1RAs and SGLT2Is treatment effect on CV endpoints by geographical region in multiple international trials using random effects weighted least squares meta-regressions.

RESULTS

The estimated effects of both SGLT2Is and GLP-1RAs on major adverse CV events (MACE) in North America (SGLT2Is n = 12,399, HR 0.90, 95% CI 0.81-1.01; GLP-1RAs n = 12,515, HR 0.95, 95% CI 0.83- 1.09) and in Europe (SGLT2Is n = 19,435, HR 0.93, 95% CI 0.85-1.02; GLP-1RAs n = 22,812, HR 0.88, 95% CI 0.79-0.99) were numerically lower but not statistically different to the rest of the world (ROW) (SGLT2Is n = 15,127, HR 0.83, 95% CI 0.75-0.92, p-value for interaction 0.26; GLP-1RAs n = 17,494, HR 0.82, 95% CI 0.73-0.92, p-value for interaction 0.28). Effects of SGLT2Is on heart failure readmission or CV death varied significantly by region (P = 0.0094). The effect of SGLT2Is was significantly smaller in Europe (n = 18,653, HR 0.86, 95% CI 0.78-0.95) than in the ROW (n = 12,463, HR 0.68, 95% CI 0.61-0.76, P = 0.0024). The smaller effect in North America (n = 9776, HR 0.76, 95% CI 0.66-0.87) did not differ significantly from that in the ROW (P = 0.2370).

CONCLUSION

The effects of SGLT2Is on HF events are larger in the ROW. Further analyses and studies are needed to better elucidate the differential effects of SGLTIs and GLP-1RAs by geographical regions.

Efficacy and safety of early initiation of eplerenone treatment in patients with acute heart failure (EARLIER trial): a multicenter, randomized, double-blind, placebo-controlled trial

AIMS

A mineralocorticoid receptor antagonist (MRA) is effective in patients with chronic heart failure; however, the effects of the early initiation of an MRA in patients with acute heart failure (AHF) have not been elucidated.

METHODS AND RESULTS

In this multicenter, randomized, double-blind, placebo-controlled, parallel-group study, we focused on the safety and effectiveness of the treatment with eplerenone, a selective MRA in 300 patients with AHF, that is, 149 in the eplerenone group and 151 in the placebo group in 27 Japanese institutions. The key inclusion criteria were (1) patients aged 20 years or older and (2) those with left ventricular ejection fraction of ≤ 40%. The primary outcome was a composite of cardiac death or first re-hospitalization due to cardiovascular disease within 6 months. The mean age of the participants was 66.8 years, 27.3% were women, and the median levels of brain natriuretic peptide were 376.0 pg/mL. The incidences of the primary outcome were 19.5% in the eplerenone group and 17.2% in the placebo group (hazard ratio (HR): 1.09, 95% confidence interval (CI): 0.642-1.855). In prespecified secondary outcomes, HR for the composite endpoint, cardiovascular death, or first re-hospitalization due to heart failure (HF) within 6 months was 0.55 (95% CI: 0.213 to 1.434). The safety profile for eplerenone was as expected.

CONCLUSION

The early initiation of eplerenone in patients with AHF could safely be utilized. The reduction of the incidence of a composite of cardiovascular death or first re-hospitalization for cardiovascular diseases by eplerenone is inconclusive because of inadequate power.

1-year results after PCI with the COMBO stent in all-comers in Asia versus Europe: Geographical insights from the COMBO collaboration

BACKGROUND

The COMBO drug-eluting stent combines sirolimus-elution from a biodegradable polymer with an anti-CD34+ antibody coating for early endothelialization.

OBJECTIVE

We investigated for geographical differences in outcomes after percutaneous coronary intervention (PCI) with the COMBO stent among Asians and Europeans.

METHODS

The COMBO Collaboration is a pooled patient-level analysis of the MASCOT and REMEDEE registries of all-comers undergoing attempted COMBO stent PCI. The primary outcome was 1-year target lesion failure (TLF), composite of cardiac death, target vessel myocardial infarction (TV-MI) and target lesion revascularization (TLR).

RESULTS

This study included 604 Asians (17.9%) and 2775 Europeans (82.1%). Asians were younger and included fewer females, with a higher prevalence of diabetes mellitus but lower prevalence of other comorbidities than Europeans. Asians had a higher prevalence of ACC/AHA C type lesions and received longer stent lengths. More Asians than Europeans were discharged on clopidogrel (86.5% vs 62.8%) rather than potent P2Y₁₂ inhibitors. One-year TLF occurred in 4.0% Asians and 4.1% of Europeans, p = 0.93. The incidence of cardiac death was higher in Asians (2.8% vs. 1.3%, p = 0.007) with similar rates of TV-MI (1.5% vs. 1.2%, p = 0.54) and definite stent thrombosis (0.3% vs. 0.5%, p = 0.84) and lower incidence of TLR than Europeans (1.0% vs. 2.5%, p = 0.025). After adjustment, differences for cardiac death and TLR were no longer significant.

CONCLUSIONS

In the COMBO collaboration, although 1-year TLF was similar regardless of geography, Asians experienced higher rates of cardiac death and lower TLR than Europeans, while incidence of TV-MI and ST was similar in both regions. Adjusted differences did not reach statistical significance. CLINICALTRIAL.

GOV IDENTIFIER-NUMBERS

NCT01874002 (REMEDEE Registry), NCT02183454 (MASCOT registry).

Baseline Predictors of Low-Density Lipoprotein Cholesterol and Systolic Blood Pressure Goal Attainment After 1 Year in the ISCHEMIA Trial

BACKGROUND

Risk factor control is the cornerstone of managing stable ischemic heart disease but is often not achieved. Predictors of risk factor control in a randomized clinical trial have not been described.

METHODS AND RESULTS

The ISCHEMIA trial (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) randomized individuals with at least moderate inducible ischemia and obstructive coronary artery disease to an initial invasive or conservative strategy in addition to optimal medical therapy. The primary aim of this analysis was to determine predictors of meeting trial goals for LDL-C (low-density lipoprotein cholesterol, goal <70 mg/dL) or systolic blood pressure (SBP, goal <140 mm Hg) at 1 year post-randomization. We included all randomized participants in the ISCHEMIA trial with baseline and 1-year LDL-C and SBP values by January 28, 2019. Among the 3984 ISCHEMIA participants (78% of 5179 randomized) with available data, 35% were at goal for LDL-C, and 65% were at goal for SBP at baseline. At 1 year, the percent at goal increased to 52% for LDL-C and 75% for SBP. Adjusted odds of 1-year LDL-C goal attainment were greater with older age (odds ratio [OR], 1.11 [95% CI, 1.03-1.20] per 10 years), lower baseline LDL-C (OR, 1.19 [95% CI, 1.17-1.22] per 10 mg/dL), high-intensity statin use (OR, 1.30 [95% CI, 1.12-1.51]), nonwhite race (OR, 1.32 [95% CI, 1.07-1.63]), and North American enrollment compared with other regions (OR, 1.32 [95% CI, 1.06-1.66]). Women were less likely than men to achieve 1-year LDL-C goal (OR, 0.68 [95% CI, 0.58-0.80]). Adjusted odds of 1-year SBP goal attainment were greater with lower baseline SBP (OR, 1.27 [95% CI, 1.22-1.33] per 10 mm Hg) and with North American enrollment (OR, 1.35 [95% CI, 1.04-1.76]).

CONCLUSIONS

In ISCHEMIA, older age, male sex, high-intensity statin use, lower baseline LDL-C, and North American location predicted 1-year LDL-C goal attainment, whereas lower baseline SBP and North American location predicted 1-year SBP goal attainment. Future studies should examine the effects of sex disparities, international practice patterns, and provider behavior on risk factor control.

Effect of coenzyme Q10 in Europeans with chronic heart failure: A sub-group analysis of the Q-SYMBIO randomized double-blind trial

BACKGROUND

Geographical differences in patient characteristics, management and outcomes in heart failure (HF) trials are well recognized. The aim of this study was to assess the consistency of the treat- ment effect of coenzyme Q10 (CoQ10) in the European sub-population of Q-SYMBIO, a randomized double-blind multinational trial of treatment with CoQ10, in addition to standard therapy in chronic HF.

METHODS

Patients with moderate to severe HF were randomized to CoQ10 300 mg daily or placebo in addition to standard therapy. At 3 months the primary short-term endpoints were changes in New York Heart Association (NYHA) functional classification, 6-min walk test, and levels of N-terminal pro-B type natriuretic peptide. At 2 years the primary long-term endpoint was major adverse cardiovascular events (MACE).

RESULTS

There were no significant changes in short-term endpoints. The primary long-term endpoint of MACE was reached by significantly fewer patients in the CoQ10 group (n = 10, 9%) compared to the placebo group (n = 33, 27%, p = 0.001). The following secondary endpoints were significantly improved in the CoQ10 group compared with the placebo group: all-cause and cardiovascular mortality, NYHA classification and left ventricular ejection fraction (LVEF). In the European sub-population, when compared to the whole group, there was greater adherence to guideline directed therapy and similar results for short- and long-term endpoints. A new finding revealed a significant improvement in LVEF.

CONCLUSIONS

The therapeutic efficacy of CoQ10 demonstrated in the Q-SYMBIO study was confirmed in the European sub-population in terms of safely reducing MACE, all-cause mortality, cardiovascular mortality, hospitalization and improvement of symptoms.

Commentary: On the levels of patient selection in registry-based randomized controlled trials

Registry-based randomized controlled trials (RCTs) are presumed to include a less-selected patient population and thus to have enhanced generalizability compared to conventional RCTs. However, this view disregards the levels of patient selection in registry-based RCTs: the registry selection level and the trial selection level. At both levels, systematic selection can occur and generalizability can be diminished. Nevertheless, using a registry as a basis for recruitment, randomization, and data collection results in an advantage: the trial selection takes place within the registry framework, where baseline characteristics of non-enrolled patients are automatically documented as well. By comparing the baseline variables of the enrolled and non-enrolled patients, the trial selection can always be investigated, which gives a sound basis for discussing the generalizability to the registry population.

Beta-Blockers in Patients with Heart Failure with Preserved Ejection Fraction: Results from The Korea Acute Heart Failure (KorAHF) Registry

Background and Objectives

Beta-blockers are indicated in patients with heart failure (HF) with reduced ejection fraction. However, their efficacy in patients with HF with preserved ejection fraction (HFpEF) is uncertain. We investigated the hypothesis that beta-blockers are associated with reduced adverse events in patients with HFpEF.

Methods

The Korea Acute Heart Failure (KorAHF) is a prospective observational multicentre cohort study. The 5,625 patients hospitalized for acute HF syndrome in 10 tertiary university hospitals across the country have been consecutively enrolled between March 2011 and February 2014. Of these patients, 2,152 patients with HFpEF (ejection fraction ≥40%) were investigated. The primary outcome was all-cause mortality according to beta-blocker use.

Results

During a median follow-up duration of 807 days, 702 patients died. In Cox proportional hazards model beta-blocker use was associated with a 14% reduced all-cause death (hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.75–0.98), but not with reduce rehospitalization (HR, 1.03; 95% CI, 0.85–1.27). In the propensity-score matched population, beta-blockers were also associated with reduced all-cause death (HR, 0.80; 95% CI, 0.69–0.94) but not with reduced rehospitalization (HR, 1.08; 95% CI, 0.87–1.33).

Conclusions

In Korean patients with HFpEF, use of beta-blockers is associated with reduced all-cause death but not with reduced rehospitalization.

Aldosterone Receptor Blockade in Heart Failure with Preserved Ejection Fraction

More than 50% of patients with clinical heart failure have a preserved ejection fraction. Despite mortality that is similar to or slightly lower than heart failure with reduced ejection fraction, trials to date have not shown a therapy that imparts a mortality benefit in heart failure with preserved ejection fraction (HFpEF). HFpEF represents a heterogeneous disorder with a complex pathophysiologic basis, and this may contribute to the negative results in clinical trials. Geographic variations in both patient selection and adherence to study medications confound the interpretation of the trial results. Mineralocorticoid receptor antagonists may be useful in selected patients.

The heart failure burden of type 2 diabetes mellitus-a review of pathophysiology and interventions

Diabetes and heart failure (HF) are both global epidemics with tremendous costs on society with increased rates of HF hospitalizations and worsened prognosis when co-existing, making it a significant "deadly duo." The evidence for pharmacological treatment of HF in patients with type 2 diabetes mellitus (T2DM) stems typically from either subgroup analyses of patients that were recruited to randomized controlled trials of HF interventions, usually in patients with reduced ejection fraction (EF), or from subgroup analyses of HF patients recruited to cardiovascular (CV) outcome trials (CVOT) of glucose lowering agents involving patients with T2DM. Studies in patients with HF with preserved EF are sparse. This review summarizes the literature on pathophysiology and interventions aiming to reduce the HF burden in T2DM and includes HF trials of ACEi, digoxin, β-blocker, ARB, If-blocker, MRA, and ARNI involving 38,600 patients, with or without prevalent diabetes, and CV outcome trials in T2DM involving 74,351 patients, with or without prevalent HF. In all HF trials, HF outcomes by prevalent diabetes were reported with an incremental risk of HF and death confessed by prevalent diabetes and a treatment effect similar to those without diabetes. All T2DM CVOTs reported on HF outcomes with heterogeneity between trials with two reporting benefits (empagliflozin and canagliflozin) and two reporting increased risk (saxagliptin, pioglitazone). In vulnerable T2DM patients with concomitant HF, guideline-recommended HF drugs are effective. When choosing glucose-lowering therapy, outcomes from available CVOTs should be considered.

Impact of Site Selection and Study Conduct on Outcomes in Global Clinical Trials

PURPOSE OF REVIEW

There are over 25 million patients living with heart failure globally. Overall, and especially post-discharge, clinical outcomes have remained poor in heart failure despite multiple trials, with both successes and failures over the last two decades. Matching therapies to the right patient population, identifying high-quality sites, and ensuring optimal trial design and execution represent important considerations in the development of novel therapeutics in this space.

RECENT FINDINGS

While clinical trials have undergone rapid globalization, this has come with regional variation in comorbidities, clinical parameters, and even clinical outcomes and treatment effects across international sites. These issues have now highlighted knowledge gaps about the conduct of trials, selection of study sites, and an unmet need to develop and identify "ideal" sites. There is a need for all stakeholders, including academia, investigators, healthcare organizations, patient advocacy groups, industry sponsors, research organizations, and regulatory authorities, to work as a multidisciplinary group to address these problems and develop practical solutions to improve trial conduct, efficiency, and execution. We review these trial-level issues using examples from contemporary studies to inform and optimize the design of future global clinical trials in heart failure.

Heart Failure Clinical Trials in East and Southeast Asia: Understanding the Importance and Defining the Next Steps

Heart failure (HF) is a major and increasing global public health problem. In Asia, aging populations and recent increases in cardiovascular risk factors have contributed to a particularly high burden of HF, with outcomes that are poorer than those in the rest of the world. Representation of Asians in landmark HF trials has been variable. In addition, HF patients from Asia demonstrate clinical differences from patients in other geographic regions. Thus, the generalizability of some clinical trial results to the Asian population remains uncertain. In this article, we review differences in HF phenotype, HF management, and outcomes in patients from East and Southeast Asia. We describe lessons learned in Asia from recent HF registries and clinical trial databases and outline strategies to improve the potential for success in future trials. This review is based on discussions among scientists, clinical trialists, industry representatives, and regulatory representatives at the CardioVascular Clinical Trialist Asia Forum in Singapore on July 4, 2014.

Pharmacological reasons that may explain why randomized clinical trials have failed in acute heart failure syndromes

Acute heart failure (AHF) represents a clinical challenge as it encloses a heterogeneous group of syndromes (AHFS) with different pathophysiology, clinical presentations, prognosis and response to therapy. In the last 25years multiple therapeutic targets have been identified and numerous new drugs were evaluated but, up to now, all failed to demonstrate a consistent benefit on clinical outcomes. Moreover, a repeated finding has been the poor correlation between the encouraging results of preclinical and early clinical trials and the lack of effect on outcomes observed in phase III trials. We review several possible pharmacological reasons that may explain the lack of success to develop new drugs and the pharmacological challenges to overcome in the future to develop new more effective and safer drugs for the treatment of AHFS.

Geographic variations in the PARADIGM-HF heart failure trial

Aims

The globalization of clinical trials has highlighted geographic variations in patient characteristics, event rates, and treatment effects. We investigated these further in PARADIGM-HF, the largest and most globally representative trial in heart failure (HF) to date.

Methods and results

We looked at five regions: North America (NA) 602 (8%), Western Europe (WE) 1680 (20%), Central/Eastern Europe/Russia (CEER) 2762 (33%), Latin America (LA) 1433 (17%), and Asia-Pacific (AP) 1487 (18%). Notable differences included: WE patients (mean age 68 years) and NA (65 years) were older than AP (58 years) and LA (63 years) and had more coronary disease; NA and CEER patients had the worst signs, symptoms, and functional status. North American patients were the most likely to have a defibrillating-device (54 vs. 2% AP) and least likely prescribed a mineralocorticoid receptor antagonist (36 vs. 65% LA). Other evidence-based therapies were used most frequently in NA and WE. Rates of the primary composite outcome of cardiovascular (CV) death or HF hospitalization (per 100 patient-years) varied among regions: NA 13.6 (95% CI 11.7–15.7) WE 9.6 (8.6–10.6), CEER 12.3 (11.4–13.2), LA 11.2 (10.0–12.5), and AP 12.5 (11.3–13.8). After adjustment for prognostic variables, relative to NA, the risk of CV death was higher in LA and AP and the risk of HF hospitalization lower in WE. The benefit of sacubitril/valsartan was consistent across regions.

Conclusion

There were many regional differences in PARADIGM-HF, including in age, symptoms, comorbidity, background therapy, and event-rates, although these did not modify the benefit of sacubitril/valsartan.

Clinical trial registration URL

http://www.clinicaltrials.gov. Unique identifier: NCT01035255.

Geographic Differences in Patients in a Global Acute Heart Failure Clinical Trial (from the ASCEND-HF Trial)

A growing number of countries and geographical regions are involved in major clinical trials. Acute Study of Clinical Effectiveness of Nesiritide in Decompensated Heart Failure is the largest trial in acutely decompensated heart failure (HF) with patients from 5 geographical regions: North America (NA), Latin America (LA), Western Europe (WE), Central Europe (CE), and Asia-Pacific (AP). Data from the 5 geographical areas were compared including baseline characteristics, medications, 30-day outcomes (mortality and mortality or HF hospitalization), and 180-day mortality. Of the 7,141 study patients, 3,243 (45.4%) were from NA (average of 15.2 patients/site), 1,762 (24.7%) from AP (28.4 patients/site), 967 (13.5%) from CE (20.2 patients/site), 665 (9.3%) from LA (17.1 patients/site), and 504 (7.1%) from WE (14.4 patients/site). There were marked differences in co-morbidities, clinical profile, medication use, length of stay, 30-day event rates, and 180-day mortality by region. Compared with NA, the adjusted risk for death or HF hospitalization at 30 days was significantly lower in CE (odds ratio [OR] 0.46, 95% CI 0.33 to 0.64), WE (OR 0.52 95% CI 0.35 to 0.75), and AP (OR 0.62 95% CI 0.48 to 0.79) and numerically lower in LA (OR 0.77, 95% CI 0.57 to 1.04) with similar results for 180-day mortality. In conclusion, in patients with acutely decompensated HF, major differences in baseline characteristics, treatments, length of the hospital stay, and 30-day HF rehospitalization rates, and 180-day mortality were found in patients enrolled from different geographical areas.

Detection and Management of Geographic Disparities in the TOPCAT Trial: Lessons Learned and Derivative Recommendations

TOPCAT was a multinational clinical trial of 3,445 heart failure with preserved ejection fraction (HFpEF) patients that enrolled in 233 sites in six countries in North America, Eastern Europe and South America. Patients with a heart failure hospitalization in the last 12 months or an elevated B-type natriuretic peptide (BNP) were randomized to the mineralocorticoid receptor antagonist spironolactone vs. placebo. Sites in Russia and the Republic of Georgia provided the majority of early enrollment, primarily based on the hospitalization criterion since BNP levels were initially unavailable there. With the emergence of country-specific aggregate event rate data indicating lower rates in Eastern Europe and differences in patient characteristics there, the DSMB recommended relatively increasing enrollment in North America plus other corrective measures. Although final enrollment reflected the increased contribution from North America, a plurality of the final cohort came from Russia and Georgia (49% vs. 43% in North America). BNP measurements from Russia and Georgia available later in the trial suggested no or a mild level of heart failure consistent with low event rates. The primary results showed no significant spironolactone treatment effect overall (primary endpoint hazard ratio 0.89 (0.77, 1.04)), with a significant hazard ratio in North and South America (0.82 (0.69, 0.98), p =0.026) but not in Russia and Georgia (1.10 (0.79, 1.51), interaction p = 0.12). This report describes the DSMB's detection and management recommendations for regional differences in patient characteristics in TOPCAT, and suggests methods of surveillance and corrective actions that may be useful for future trials.

In-Hospital Diuretic Agent Use and Post-Discharge Clinical Outcomes in Patients Hospitalized for Worsening Heart Failure: Insights From the EVEREST Trial

OBJECTIVES

The aim of this study was to characterize the association between decongestion therapy and 30-day outcomes in patients hospitalized for heart failure (HF).

BACKGROUND

Loop diuretic agents are commonly prescribed for the treatment of symptomatic congestion in patients hospitalized for HF, but the association between loop diuretic agent dose response and post-discharge outcomes has not been well characterized.

METHODS

Cox proportional hazards models were used to estimate the association among average loop diuretic agent dose, congestion status at discharge, and 30-day post-discharge all-cause mortality and HF rehospitalization in 3,037 subjects hospitalized with worsening HF enrolled in the EVEREST (Efficacy of Vasopressin Antagonism in Heart Failure: Outcome Study With Tolvaptan) study.

RESULTS

In univariate analysis, subjects exposed to high-dose diuretic agents (≥160 mg/day) had greater risk for the combined outcome than subjects exposed to low-dose diuretic agents (18.9% vs. 10.0%; hazard ratio: 2.00; 95% confidence interval: 1.64 to 2.46; p < 0.0001). After adjustment for pre-specified covariates of disease severity, the association between diuretic agent dose and outcomes was not significant (hazard ratio: 1.11; 95% confidence interval: 0.89 to 1.38; p = 0.35). Of the 3,011 subjects with clinical assessments of volume status, 2,063 (69%) had little or no congestion at hospital discharge. Congestion status at hospital discharge did not modify the association between diuretic agent exposure and the combined endpoint (p for interaction = 0.84).

CONCLUSIONS

Short-term diuretic agent exposure during hospital treatment for worsening HF was not an independent predictor of 30-day all-cause mortality and HF rehospitalization in multivariate analysis. Congestion status at discharge did not modify the association between diuretic agent dose and clinical outcomes.

Geographic differences in heart failure trials

Randomized controlled trials (RCTs) are essential to develop advances in heart failure (HF). The need for increasing numbers of patients (without substantial cost increase) and generalization of results led to the disappearance of international boundaries in large RCTs. The significant geographic differences in patients' characteristics, outcomes, and, most importantly, treatment effect observed in HF trials have recently been highlighted. Whether the observed regional discrepancies in HF trials are due to trial-specific issues, patient heterogeneity, structural differences in countries, or a complex interaction between factors are the questions we propose to debate in this review. To do so, we will analyse and review data from HF trials conducted in different world regions, from heart failure with preserved ejection fraction (HF-PEF), heart failure with reduced ejection fraction (HF-REF), and acute heart failure (AHF). Finally, we will suggest objective and actionable measures in order to mitigate regional discrepancies in future trials, particularly in HF-PEF where prognostic modifying treatments are urgently needed and in which trials are more prone to selection bias, due to a larger patient heterogeneity.

Patient selection in heart failure with preserved ejection fraction clinical trials

Recent clinical trials in patients with heart failure with preserved ejection fraction (HFpEF) have provided important insights into participant selection strategies. Historically, HFpEF trials have included patients with relatively preserved left ventricular ejection fraction ranging from 40% to 55% and a clinical history of heart failure. Contemporary HFpEF trials have also incorporated inclusion criteria such as hospitalization for HFpEF, altered functional capacity, cardiac structural and functional abnormalities, and abnormalities in neurohormonal status (e.g., elevated natriuretic peptide levels). Careful analyses of the effect of these patient selection criteria on outcomes in prior trials provide valuable lessons for future trial design. We review recent and ongoing HFpEF clinical trials from a patient selection perspective and appraise trial patient selection methodologies in relation to outcomes. This review reflects discussions between clinicians, scientists, trialists, regulators, and regulatory representatives at the 10th Global CardioVascular Clinical Trialists Forum in Paris, France, on December 6, 2013.

Industry-sponsored clinical research outside high-income countries: an empirical analysis of registered clinical trials from 2006 to 2013

Background

Industry-sponsored clinical trials, in the past performed almost exclusively in more developed countries, now often recruit participants globally. However, recruitment from outside high-income countries may not represent the ultimate target population for the intervention. Clinical trial registries provide an opportunity to quantify and examine the type of clinical research performed in various geographic regions. We sought to characterize industry-sponsored randomized controlled trials conducted in high-income countries and to compare these trials to those performed outside high-income countries.

Methods

Clinical trial data on all industry-funded randomized controlled trials conducted between 2006 and 2014 were obtained from the registry ClinicalTrials.gov. Trials were classified according to their study sites as conducted in high or non-high income countries, and data on trial characteristics were collected.

Results

Of 22,511 relevant trials, a total of 6,085 (27.0 %) trials included study sites outside a high-income country, and 2,045 (9.1 %) were conducted exclusively outside high-income countries. Of country groups, Central Europe had the greatest number of trials (3,127), followed by Eastern Europe (2,075). The percentage of trials with study sites outside high-income countries remained relatively constant over the study period. Studies with sites outside high-income countries tended to recruit more participants (median enrolled participants 265 vs. 71, P <0.001), to be longer (median study duration 20 vs. 13 months, P <0.05), and to study more advanced phase interventions (Phase 3 or 4 trial 58 % vs. 33 %, P <0.001).

Conclusions

More than a quarter of industry-sponsored trials include participants from outside high-income countries and this rate remained stable over the 7-year study period. Trials conducted outside high-income countries tend to be larger, have a longer duration, and study later phase interventions compared to studies performed exclusively in high-income countries.

Electronic supplementary material

The online version of this article (doi:10.1186/s12961-015-0019-6) contains supplementary material, which is available to authorized users.

Improving cardiovascular clinical trials conduct in the United States: recommendation from clinicians, researchers, sponsors, and regulators

Advances in medical therapies leading to improved patient outcomes are in large part related to successful conduct of clinical trials that offer critical information regarding the efficacy and safety of novel interventions. The conduct of clinical trials in the United States, however, continues to face increasing challenges with recruitment and retention. These trends are paralleled by an increasing shift toward more multinational trials where most participants are enrolled in countries outside the United States, bringing into question the generalizability of the results to the American population. This manuscript presents the perspectives and recommendations from clinicians, researchers, sponsors, and regulators who attended a meeting facilitated by the Food and Drug Administration to improve upon the current clinical trial trends in the United States.

International geographic variation in event rates in trials of heart failure with preserved and reduced ejection fraction

BACKGROUND

International geographic differences in outcomes may exist for clinical trials of heart failure and reduced ejection fraction (HF-REF), but there are few data for those with preserved ejection fraction (HF-PEF).

METHODS AND RESULTS

We analyzed outcomes by international geographic region in the Irbesartan in Heart Failure with Preserved systolic function trial (I-Preserve), the Candesartan in Heart failure Assessment of Reduction in Mortality and morbidity (CHARM)-Preserved trial, the CHARM-Alternative and CHARM-Added HF-REF trials, and the Controlled Rosuvastatin Multinational Trial in HF-REF (CORONA). Crude rates of heart failure hospitalization varied by geographic region, and more so for HF-PEF than for HF-REF. Rates in patients with HF-PEF were highest in the United States/Canada (HF hospitalization rate 7.6 per 100 patient-years in I-Preserve; 8.8 in CHARM-Preserved), intermediate in Western Europe (4.8/100 and 4.7/100), and lowest in Eastern Europe/Russia (3.3/100 and 2.8/100). The difference between the United States/Canada versus Eastern Europe/Russia persisted after adjustment for key prognostic variables: adjusted hazard ratios 1.34 (95% confidence interval, 1.01-1.74; P=0.04) in I-Preserve and 1.85 (95% confidence interval, 1.17-2.91; P=0.01) in CHARM-Preserved. In HF-REF, rates of HF hospitalization were slightly lower in Western Europe compared with other regions. For both HF-REF and HF-PEF, there were few regional differences in rates of all-cause or cardiovascular mortality.

CONCLUSIONS

The differences in event rates observed suggest there is international geographic variation in 1 or more of the definition and diagnosis of HF-PEF, the risk profile of patients enrolled, and the threshold for hospitalization, which has implications for the conduct of future global trials.

Beta-blockers Associated with a Mortality Benefit in Patients with Systolic Dysfunction and Elevated Serum Bilirubin

Background:

Hyperbilirubinemia is associated with increased mortality in heart failure (HF) patients. We evaluated the impact of evidence-based medical therapy, in particular beta-blocker on the survival of patients with HF and hyperbilirubinemia.

Methods and Results:

We reviewed the charts of all patients followed at our tertiary care heart failure clinic. Hyperbilirubinemia was defined as total bilirubin >30 µmol/L (1.5 times the upper limit of our laboratory value). The primary endpoint was all-cause mortality. The secondary endpoint was a composite of death, cardiac transplant or ventricular assistance device implantation (VAD). Of 1035 HF patients, 121 patients (11.7%) had hyperbilirubinemia. Median follow-up was 556 days. Hyperbilirubinemia was associated with an eight-fold increase in all-cause mortality, hazard ratio (HR): 8.78[95% Confidence Intervals (CI): 5.89-13.06]. Beta-blocker use was associated with approximately 60% reduction in all-cause mortality (HR: 0.38, 95% CI:0.15-0.94) and 70% reduction in the composite secondary endpoint (HR:0.31, 95% CI:0.13-0.71) in patients with hyperbilirubinemia.

Conclusion:

HF patients with hyperbilirubinemia have increased early mortality, need for cardiac transplantation or VAD. Beta-blocker use was associated with early survival benefit in these patients. Bilirubin levels should be monitored in patients with HF and early initiation of beta-blockers in patients with hyperbilirubinemia should be considered.

The autonomic nervous system and heart failure

The pathophysiology of heart failure (HF) is characterized by hemodynamic abnormalities that result in neurohormonal activation and autonomic imbalance with increase in sympathetic activity and withdrawal of vagal activity. Alterations in receptor activation from this autonomic imbalance may have profound effects on cardiac function and structure. Inhibition of the sympathetic drive to the heart through β-receptor blockade has become a standard component of therapy for HF with a dilated left ventricle because of its effectiveness in inhibiting the ventricular structural remodeling process and in prolonging life. Several devices for selective modulation of sympathetic and vagal activity have recently been developed in an attempt to alter the natural history of HF. The optimal counteraction of the excessive sympathetic activity is still unclear. A profound decrease in adrenergic support with excessive blockade of the sympathetic nervous system may result in adverse outcomes in clinical HF. In this review, we analyze the data supporting a contributory role of the autonomic functional alterations on the course of HF, the techniques used to assess autonomic nervous system activity, the evidence for clinical effectiveness of pharmacological and device interventions, and the potential future role of autonomic nervous system modifiers in the management of this syndrome.

International differences in clinical characteristics, management, and outcomes in acute heart failure patients: better short-term outcomes in patients enrolled in Eastern Europe and Russia in the PROTECT trial

AIMS

The implications of geographical variation are unknown following adjustment for hospital length of stay (LOS) in heart failure (HF) trials that included patients whether or not they had systolic dysfunction. We investigated regional differences in an international acute HF trial.

METHODS AND RESULTS

The PROTECT trial investigated 2033 patients with acute HF and renal dysfunction hospitalized at 173 sites in 17 countries with randomization to rolofylline or placebo. We grouped enrolling countries into six regions. Baseline characteristics, in-hospital management, and outcomes were explored by region. The primary study outcome was 60-day mortality or cardiovascular/renal hospitalization. Secondary outcomes included 180-day mortality. Of 2033 patients, 33% were from Eastern Europe, 19% from Western Europe, 16% from Israel, 15% from North America, 14% from Russia, and 3% from Argentina. Marked differences in baseline characteristics, HF phenotype, in-hospital diuretic and vasodilator strategies, and LOS were observed by region. LOS was shortest in North America and Israel (median 5 days) and longest in Russia (median 15 days). Regional event rates varied significantly. Following multivariable adjustment, region was an independent predictor of the risk of mortality/hospitalization at 60 days, with the lowest risk in Russia (hazard ratio 0.39, 95% confidence interval 0.23-0.64 vs. Western Europe) due to lower rehospitalization; mortality differences were attenuated by 180 days.

CONCLUSIONS

In an international HF trial, there were differences in baseline characteristics, treatments, LOS, and rehospitalization amongst regions, but little difference in longer term mortality. Rehospitalization differences exist independent of LOS. This analysis may help inform future trial design and should be externally validated.

Spironolactone for heart failure with preserved ejection fraction

BACKGROUND

Mineralocorticoid-receptor antagonists improve the prognosis for patients with heart failure and a reduced left ventricular ejection fraction. We evaluated the effects of spironolactone in patients with heart failure and a preserved left ventricular ejection fraction.

METHODS

In this randomized, double-blind trial, we assigned 3445 patients with symptomatic heart failure and a left ventricular ejection fraction of 45% or more to receive either spironolactone (15 to 45 mg daily) or placebo. The primary outcome was a composite of death from cardiovascular causes, aborted cardiac arrest, or hospitalization for the management of heart failure.

RESULTS

With a mean follow-up of 3.3 years, the primary outcome occurred in 320 of 1722 patients in the spironolactone group (18.6%) and 351 of 1723 patients in the placebo group (20.4%) (hazard ratio, 0.89; 95% confidence interval [CI], 0.77 to 1.04; P=0.14). Of the components of the primary outcome, only hospitalization for heart failure had a significantly lower incidence in the spironolactone group than in the placebo group (206 patients [12.0%] vs. 245 patients [14.2%]; hazard ratio, 0.83; 95% CI, 0.69 to 0.99, P=0.04). Neither total deaths nor hospitalizations for any reason were significantly reduced by spironolactone. Treatment with spironolactone was associated with increased serum creatinine levels and a doubling of the rate of hyperkalemia (18.7%, vs. 9.1% in the placebo group) but reduced hypokalemia. With frequent monitoring, there were no significant differences in the incidence of serious adverse events, a serum creatinine level of 3.0 mg per deciliter (265 μmol per liter) or higher, or dialysis.

CONCLUSIONS

In patients with heart failure and a preserved ejection fraction, treatment with spironolactone did not significantly reduce the incidence of the primary composite outcome of death from cardiovascular causes, aborted cardiac arrest, or hospitalization for the management of heart failure. (Funded by the National Heart, Lung, and Blood Institute; TOPCAT ClinicalTrials.gov number, NCT00094302.).

How to define 'best practice' for use in Knowledge Translation research: a practical, stepped and interactive process

OBJECTIVES

Defining 'best practice' is one of the first and crucial steps in any Knowledge Translation (KT) research project. Without a sound understanding of what exactly should happen in practice, it is impossible to measure the extent of existing gaps between 'desired' and 'actual' care, set implementation goals, and monitor performance. The aim of this paper is to present a practical, stepped and interactive process to develop best practice recommendations that are actionable, locally applicable and in line with the best available research-based evidence, with a view to adapt these into process measures (quality indicators) for KT research purposes.

METHODS

Our process encompasses the following steps: (1) identify current, high-quality clinical practice guidelines (CPGs) and extract recommendations; (2) select strong recommendations in key clinical management areas; (3) update evidence and create evidence overviews; (4) discuss evidence and produce agreed 'evidence statements'; (5) discuss the relevance of the evidence with local stakeholders; and (6) develop locally applicable actionable best practice recommendations, suitable for use as the basis of quality indicators.

CONCLUSIONS

Actionable definitions of local best practice are a prerequisite for doing KT research. As substantial resources go into rigorously synthesizing evidence and developing CPGs, it is important to make best use of such available resources. We developed a process for efficiently developing locally applicable actionable best practice recommendations from existing high-quality CPGs that are in line with current research evidence.

Do countries or hospitals with longer hospital stays for acute heart failure have lower readmission rates?: Findings from ASCEND-HF

BACKGROUND

Hospital readmission is an important clinical outcome of patients with heart failure. Its relation to length of stay for the initial hospitalization is not clear.

METHODS AND RESULTS

We used hierarchical modeling of data from a clinical trial to examine variations in length of stay across countries and across hospitals in the United States and its association with readmission within 30 days of randomization. Main outcomes included associations between country-level length of stay and readmission rates, after adjustment for patient-level case mix; and associations between length of stay and readmission rates across sites in the United States. Across 27 countries with 389 sites and 6848 patients, mean length of stay ranged from 4.9 to 14.6 days (6.1 days in the United States). Rates of all-cause readmission ranged from 2.5% to 25.0% (17.8% in the United States). There was an inverse correlation between country-level mean length of stay and readmission (r=-0.52; P<0.01). After multivariable adjustment, each additional inpatient day across countries was associated with significantly lower risk of all-cause readmission (odds ratio, 0.86; 95% confidence interval, 0.75-0.98; P=0.02) and heart failure readmission (odds ratio, 0.79; 95% confidence interval, 0.69-0.99; P=0.03). Similar trends were observed across US study sites concerning readmission for any cause (odds ratio, 0.92; 95% confidence interval, 0.85-1.00; P=0.06) and readmission for heart failure (odds ratio, 0.90; 95% confidence interval, 0.80-1.01; P=0.07). Across countries and across US sites, longer median length of stay was independently associated with lower risk of readmission.

CONCLUSIONS

Countries with longer length of stay for heart failure hospitalizations had significantly lower rates of readmission within 30 days of randomization. These findings may have implications for developing strategies to prevent readmission, defining quality measures, and designing clinical trials in acute heart failure.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00475852.

Rescuing clinical trials in the United States and beyond: a call for action

Numerous challenges-financial, regulatory, and cultural-are hindering US participation and performance in multinational clinical trials. Consequently, it is increasingly unclear how the results of these trials should be applied to American patients, practice patterns, and systems of care. Both incremental and transformative changes are needed to revitalize US participation as well as the broader clinical trial enterprise. To promote consensus around the solutions needed to address the adverse trends in clinical research, the Duke Clinical Research Institute convenedstakeholders from academia, industry, and government. article summarizes the proceedings of this meeting and addresses: (1) adverse trends in the United States and multinational clinical trials, (2) the key issues that underlie these adverse trends, and (3) potential solutions to these problems.

Benefits of β blockers in patients with heart failure and reduced ejection fraction: network meta-analysis

OBJECTIVE

To clarify whether any particular β blocker is superior in patients with heart failure and reduced ejection fraction or whether the benefits of these agents are mainly due to a class effect.

DESIGN

Systematic review and network meta-analysis of efficacy of different β blockers in heart failure.

DATA SOURCES

CINAHL(1982-2011), Cochrane Collaboration Central Register of Controlled Trials (-2011), Embase (1980-2011), Medline/PubMed (1966-2011), and Web of Science (1965-2011).

STUDY SELECTION

Randomized trials comparing β blockers with other β blockers or other treatments.

DATA EXTRACTION

The primary endpoint was all cause death at the longest available follow-up, assessed with odds ratios and Bayesian random effect 95% credible intervals, with independent extraction by observers.

RESULTS

21 trials were included, focusing on atenolol, bisoprolol, bucindolol, carvedilol, metoprolol, and nebivolol. As expected, in the overall analysis, β blockers provided credible mortality benefits in comparison with placebo or standard treatment after a median of 12 months (odds ratio 0.69, 0.56 to 0.80). However, no obvious differences were found when comparing the different β blockers head to head for the risk of death, sudden cardiac death, death due to pump failure, or drug discontinuation. Accordingly, improvements in left ventricular ejection fraction were also similar irrespective of the individual study drug.

CONCLUSION

The benefits of β blockers in patients with heart failure with reduced ejection fraction seem to be mainly due to a class effect, as no statistical evidence from current trials supports the superiority of any single agent over the others.

Combinatorial pharmacogenetic interactions of bucindolol and β1, α2C adrenergic receptor polymorphisms

Background

Pharmacogenetics involves complex interactions of gene products affecting pharmacodynamics and pharmacokinetics, but there is little information on the interaction of multiple genetic modifiers of drug response. Bucindolol is a β-blocker/sympatholytic agent whose efficacy is modulated by polymorphisms in the primary target (β₁ adrenergic receptor [AR] Arg389 Gly on cardiac myocytes) and a secondary target modifier (α_2C AR Ins [wild-type (Wt)] 322–325 deletion [Del] on cardiac adrenergic neurons). The major allele homozygotes and minor allele carriers of each polymorphism are respectively associated with efficacy enhancement and loss, creating the possibility for genotype combination interactions that can be measured by clinical trial methodology.

Methodology

In a 1,040 patient substudy of a bucindolol vs. placebo heart failure clinical trial, we tested the hypothesis that combinations of β₁389 and α_2C322–325 polymorphisms are additive for both efficacy enhancement and loss. Additionally, norepinephrine (NE) affinity for β₁389 AR variants was measured in human explanted left ventricles.

Principal Findings

The combination of β₁389 Arg+α_2C322–325 Wt major allele homozygotes (47% of the trial population) was non-additive for efficacy enhancement across six clinical endpoints, with an average efficacy increase of 1.70-fold vs. 2.32-fold in β₁389 Arg homozygotes+α_2C322–325 Del minor allele carriers. In contrast, the minor allele carrier combination (13% subset) exhibited additive efficacy loss. These disparate effects are likely due to the higher proportion (42% vs. 8.7%, P = 0.009) of high-affinity NE binding sites in β₁389 Arg vs. Gly ARs, which converts α_2CDel minor allele-associated NE lowering from a therapeutic liability to a benefit.

Conclusions

On combination, the two sets of AR polymorphisms 1) influenced bucindolol efficacy seemingly unpredictably but consistent with their pharmacologic interactions, and 2) identified subpopulations with enhanced (β₁389 Arg homozygotes), intermediate (β₁389 Gly carriers+α_2C322–325 Wt homozygotes), and no (β₁389 Gly carriers+α_2C322–325 Del carriers) efficacy.

Implications of geographical variation on clinical outcomes of cardiovascular trials

Cardiovascular clinical trials are increasingly conducted globally as a means to reduce costs, expedite timelines, provide broad applicability, and satisfy regulatory authorities. Potential problems with trial globalization include regional differences in patient characteristics, medical practice patterns, and health policies which may influence outcomes and limit generalizability. Moreover, concerns have been raised about ethical misconduct and unsatisfactory quality oversight in regions with less trial experience and infrastructure. This article reviews geographical differences in cardiovascular trials in heart failure, acute coronary syndromes, hypertension and atrial fibrillation. It also explores potential explanations for these differences and methods to standardize the presentation of trial results. This review is based on discussions between basic scientists and clinical trialists at the 8th Global Cardio Vascular Clinical Trialists Forum 2011 in Paris, France, from December 2 to 3.