Prognostic Impact of Sinus Rhythm in Atrial Fibrillation Patients: Separating Rhythm Outcomes From Randomized Strategy Findings From the CABANA Trial

BACKGROUND

Clinically detected atrial fibrillation (AF) is associated with a significant increase in mortality and other adverse cardiovascular events. Since the advent of effective methods for AF rhythm control, investigators have attempted to determine how much these adverse prognostic AF effects could be mitigated by the restoration of sinus rhythm (SR) and whether the method used mattered.

METHODS

The CABANA trial (Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) randomized 2204 AF patients to ablation versus drug therapy, of which 1240 patients were monitored in follow-up using the CABANA ECG rhythm monitoring system. To assess the prognostic benefits of SR, we performed a prespecified analysis using Cox survival modeling with heart rhythm as a time-dependent variable and randomized treatment group as a stratification factor.

RESULTS

In the 1240 patient study cohort, 883 (71.2%) had documented AF at some point during their postblanking follow-up. Among the 883 patients, 671 (76.0%) experienced AF within the first year of postblanking follow-up, and 212 (24.0%) experienced their first AF after ≥1 year of postblanking follow-up. The primary CABANA end point (death, disabling stroke, serious bleeding, or cardiac arrest) occurred in 95 (10.8%) of the 883 patients with documented AF and in 29 (8.1%) of the 357 patients with no AF recorded during follow-up. In multivariable time-dependent analysis, the presence of SR (compared with non-SR) was associated with a significantly reduced risk of the primary end point (adjusted hazard ratio, 0.57 [95% CI, 0.38-0.85]; P=0.006; independent of treatment strategy [ablation versus drugs]). Corresponding results for all-cause mortality were adjusted hazard ratio of 0.59 [95% CI, 0.35-1.01]; P=0.053).

CONCLUSIONS

In patients in the CABANA trial with detailed long-term rhythm follow-up, increased time in SR was associated with a clinically consequential decrease in mortality and other adverse prognostic events. The predictive value of SR was independent of the therapeutic approach responsible for reducing the burden of detectable AF.

REGISTRATION

URL: https://clinicaltrials.gov; Unique Identifier: NCT00911508.

Regional differences in outcomes with ablation versus drug therapy for atrial fibrillation: Results from the CABANA trial

BACKGROUND

The finding of unexpected variations in treatment benefits by geographic region in international clinical trials raises complex questions about the interpretation and generalizability of trial findings. We observed such geographical variations in outcome and in the effectiveness of atrial fibrillation (AF) ablation versus drug therapy in the Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation (CABANA) trial. This paper describes these differences and investigates potential causes.

METHODS

The examination of treatment effects by geographic region was a prespecified analysis. CABANA enrolled patients from 10 countries, with 1,285 patients at 85 North American (NA) sites and 919 at 41 non-NA sites. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Death and first atrial fibrillation recurrence were secondary endpoints.

RESULTS

At least 1 primary endpoint event occurred in 157 patients (12.2%) from NA and 33 (3.6%) from non-NA sites over a median 54.9 and 40.5 months of follow-up, respectively (NA/non-NA adjusted hazard ratio (HR) 2.18, 95% confidence interval (CI) 1.48-3.21, P < .001). In NA patients, 78 events occurred in the ablation and 79 in the drug arm, (HR 0.91, 95% CI 0.66, 1.24) while 11 and 22 events occurred in non-NA patients (HR 0.51, 95% CI 0.25,1.05, interaction P = .154). Death occurred in 53 ablation and 51 drug therapy patients in the NA group (HR 0.96, 95% CI 0.65,1.42) and in 5 ablation and 16 drug therapy patients in the non-NA group (HR 0.32, 95% CI 0.12,0.86, interaction P = .044). Adjusting for baseline regional differences or prognostic risk variables did not account for the regional differences in treatment effects. Atrial fibrillation recurrence was reduced by ablation in both regions (NA: HR 0.54, 95% CI 0.46, 0.63; non-NA: HR 0.44, 95% CI 0.30, 0.64, interaction P = .322).

CONCLUSIONS

In CABANA, primary outcome events occurred significantly more often in the NA group but assignment to ablation significantly reduced all-cause mortality in the non-NA group only. These differences were not explained by regional variations in procedure effectiveness, safety, or patient characteristics.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT0091150; https://clinicaltrials.gov/study/NCT00911508.

Effects of Ablation Versus Drug Therapy on Quality of Life by Sex in Atrial Fibrillation: Results From the CABANA Trial

Background Women with atrial fibrillation (AF) demonstrate more AF-related symptoms and worse quality of life (QOL). Whether increased use of ablation in women reduces sex-related QOL differences is unknown. Sex-related outcomes for ablation versus drug therapy was a prespecified analysis in the CABANA (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) trial. Methods and Results Symptoms were assessed periodically over 60 months with the Mayo AF-Specific Symptom Inventory (MAFSI) frequency score, and QOL was assessed with the Atrial Fibrillation Effect on Quality of Life (AFEQT) summary and component scores. Women had lower baseline QOL scores than men (mean AFEQT scores 55.9 and 65.6, respectively). Ablation patients improved more than drug therapy patients with similar treatment effect by sex: AFEQT 12-month mean adjusted treatment difference in women 6.1 points (95% CI, 3.5-8.6) and men 4.9 points (95% CI, 3.0-6.9). Participants with baseline AFEQT summary scores <70 had greater QOL improvement, with a mean treatment difference at 12 months of 7.6 points for women (95% CI, 4.3-10.9) and 6.4 points for men (95% CI, 3.3-9.4). The mean adjusted difference in MAFSI frequency score between women randomized to ablation versus drug therapy at 12 months was -2.5 (95% CI, -3.4 to -1.6); for men, the difference was -1.3 (95% CI, -2.0 to -0.6). Conclusions Compared with drug therapy for AF, ablation resulted in more QOL improvement in both sexes, primarily driven by improvements in those with lower baseline QOL. Ablation did not eliminate the AF-related QOL gap between women and men. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00911508.

Genetic ablation of the preptin-coding portion of Igf2 impairs pancreatic function in female mice

Preptin is a 34-amino acid peptide derived from the E-peptide of pro-insulin-like growth factor 2 and is co-secreted with insulin from β-cells. Little is understood about the effects of endogenous preptin on whole body glucose metabolism. We developed a novel mouse model in which the preptin portion of Igf2 was genetically ablated in all tissues, hereafter referred to as preptin knockout (KO), and tested the hypothesis that the removal of preptin will lead to a decreased insulin response to a metabolic challenge. Preptin KO and wild-type (WT) mice underwent weekly fasting blood glucose measurements, intraperitoneal insulin tolerance tests (ITT) at 9, 29, and 44 wk of age, and an oral glucose tolerance test (GTT) at 45 wk of age. Preptin KO mice of both sexes had similar Igf2 exon 2-3 mRNA expression in the liver and kidney compared with WT mice, but Igf2 exon 3-4 (preptin) expression was not detectable. Western blot analysis of neonatal serum indicated that processing of pro-IGF2 translated from the KO allele may be altered. Preptin KO mice had similar body weight, body composition, β-cell area, and fasted glucose concentrations compared with WT mice in both sexes up to 47 wk of age. Female KO mice had a diminished ability to mount an insulin response following glucose stimulation in vivo. This effect was absent in male KO mice. Although preptin is not essential for glucose homeostasis, when combined with previous in vitro and ex vivo findings, these data show that preptin positively impacts β-cell function.NEW & NOTEWORTHY This is the first study to describe a model in which the preptin-coding portion of the Igf2 gene has been genetically ablated in mice. The mice do not show reduced size at birth associated with Igf2 knockout suggesting that IGF2 functionality is maintained, yet we demonstrate a change in the processing of mature Igf2. Female knockout mice have diminished glucose-stimulated insulin secretion, whereas the insulin response in males is not different to wild type.

Prognostically distinct phenotypes of metabolic health beyond obesity in aortic stenosis

Background

Whilst current evidence are in favour of metabolic health and non-obesity in the reduction of incident cardiovascular disease, little is known regarding the prognosis across the metabolic phenotypes once cardiovascular disease occurs. This study examined the prognosis of patients with significant aortic stenosis (AS) based on the presence of metabolic health and obesity.

Methods

This retrospective cohort on consecutive patients presenting with moderate-to-severe AS to a tertiary hospital between 2010 and 2015. Patients were allocated into 4 groups based on obesity and metabolic health: metabolically healthy obese (MHO), metabolically healthy non-obese (MHNO), metabolically unhealthy obese (MUO) and metabolically unhealthy non-obese (MUNO). Metabolic health was defined in accordance to Program Adult Treatment Panel III criteria. The primary outcome was all-cause mortality. Cox regression examined independent associations between mortality and metabolic phenotypes, adjusting for aortic valve area, ejection fraction, age, sex, chronic kidney disease and AVR as a time-dependent covariate.

Results

Of 727 patients, the majority (51.6%) were MUNO, followed by MUO (32.7%), MHNO (11.4%), and MHO (4.3%). MHNO had the highest mortality (43.0%), followed by the MUNO (37.5%), MUO (30.0%) and MHO (6.9%) groups (p=0.001). Compared to MHNO, MHO (HR 0.159, 95% CI 0.038–0.668, p=0.012) and MUO (HR 0.614, 95% CI 0.403–0.937, p=0.024) were independently associated with lower all-cause mortality rates, after adjusting for confounders. In obese patients, metabolic health had favourable survival compared to metabolically unhealthy (p=0.015), but this protective impact of metabolic health was not observed in overweight or normal weight individuals. Obesity had favourable survival compared to overweight and normal weight, in both metabolically health (p=0.002) and unhealthy (p=0.007) patients,

Conclusion

MHO patients with AS have the most favourable prognosis whilst the seemingly healthy MHNO group had the worst survival. There should be a paradigm shift towards prioritising metabolic health rather than weight reduction in patients with significant AS.

Funding Acknowledgement

Type of funding sources: None.

Cost-Effectiveness of Catheter Ablation Versus Antiarrhythmic Drug Therapy in Atrial Fibrillation: The CABANA Randomized Clinical Trial

BACKGROUND

In the CABANA trial (Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation), catheter ablation did not significantly reduce the primary end point of death, disabling stroke, serious bleeding, or cardiac arrest compared with drug therapy by intention-to-treat, but did improve the quality of life and freedom from atrial fibrillation recurrence. In the heart failure subgroup, ablation improved both survival and quality of life. Cost-effectiveness was a prespecified CABANA secondary end point.

METHODS

Medical resource use data were collected for all CABANA patients (N=2204). Costs for hospital-based care were assigned using prospectively collected bills from US patients (n=1171); physician and medication costs were assigned using the Medicare Fee Schedule and National Average Drug Acquisition Costs, respectively. Extrapolated life expectancies were estimated using age-based survival models. Quality-of-life adjustments were based on EQ-5D-based utilities measured during the trial. The primary outcome was the incremental cost-effectiveness ratio, comparing ablation with drug therapy on the basis of intention-to-treat, and assessed from the US health care sector perspective.

RESULTS

Costs in the first 3 months averaged $20 794±SD 1069 higher with ablation compared with drug therapy. The cumulative within-trial 5-year cost difference was $19 245 (95% CI, $11 360-$27 170) and the lifetime mean cost difference was $15 516 (95% CI, -$2963 to $35,512) higher with ablation than with drug therapy. The drug therapy arm accrued an average of 12.5 life-years (LYs) and 10.7 quality-adjusted life-years (QALYs). For the ablation arm, the corresponding estimates were 12.6 LYs and 11.0 QALYs. The incremental cost-effectiveness ratio was $57 893 per QALY gained, with 75% of bootstrap replications yielding an incremental cost-effectiveness ratio <$100 000 per QALY gained. With no quality-of-life/utility adjustments, the incremental cost-effectiveness ratio was $183 318 per LY gained.

CONCLUSIONS

Catheter ablation of atrial fibrillation was economically attractive compared with drug therapy in the CABANA Trial overall at present benchmarks for health care value in the United States on the basis of projected incremental QALYs but not LYs alone.

Influence of atrial fibrillation type on outcomes of ablation vs. drug therapy: results from CABANA

AIMS

Influence of atrial fibrillation (AF) type on outcomes seen with catheter ablation vs. drug therapy is incompletely understood. This study assesses the impact of AF type on treatment outcomes in the Catheter Ablation vs. Antiarrhythmic Drug Therapy for Atrial Fibrillation Trial (CABANA).

METHODS AND RESULTS

CABANA randomized 2204 patients ≥65 years old or <65 with at least one risk factor for stroke to catheter ablation or drug therapy. Of these, 946 (42.9%) had paroxysmal AF (PAF), 1042 (47.3%) had persistent AF (PersAF), and 215 (9.8%) had long-standing persistent AF (LSPAF) at baseline. The primary endpoint was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Symptoms were measured with the Mayo AF-Specific Symptom Inventory (MAFSI), and quality of life was measured with the Atrial Fibrillation Effect on Quality of Life (AFEQT). Comparisons are reported by intention to treat. Compared with drug therapy alone, catheter ablation produced a 19% relative risk reduction in the primary endpoint for PAF {adjusted hazard ratio [aHR]: 0.81 [95% confidence interval (CI): 0.50, 1.30]}, and a 17% relative reduction for PersAF (aHR: 0.83, 95% CI: 0.56, 1.22). For LSPAF, the ablation relative effect was a 7% reduction (aHR: 0.93, 95% CI: 0.36, 2.44). Ablation was more effective than drug therapy at reducing first AF recurrence in all AF types: by 51% for PAF (aHR: 0.49, 95% CI: 0.39, 0.62), by 47% for PersAF (aHR: 0.53, 95% CI: 0.43,0.65), and by 36% for LSPAF (aHR 0.64, 95% CI 0.41,1.00). Ablation was associated with greater improvement in symptoms, with the mean difference between groups in the MAFSI frequency score favouring ablation over 5 years of follow-up in all subgroups: PAF had a clinically significant -1.9-point difference (95% CI: -1.2 to -2.6); PersAF a -0.9 difference (95% CI: -0.2 to -1.6); LSPAF a clinically significant difference of -1.6 points (95% CI: -0.1 to -3.1). Ablation was also associated with greater improvement in quality of life in all subgroups, with the AFEQT overall score in PAF patients showing a clinically significant 5.3-point improvement (95% CI: 3.3 to 7.3) over drug therapy alone over 5 years of follow-up, PersAF a 1.7-point difference (95% CI: 0.0 to 3.7), and LSPAF a 3.1-point difference (95% CI: -1.6 to 7.8).

CONCLUSION

Prognostic treatment effects of catheter ablation compared with drug therapy on the primary and major secondary clinical endpoints did not differ consequentially by AF subtype. With regard to decreases in AF recurrence and improving quality of life, ablation was more effective than drug therapy in all three AF type subgroups.

CLINICALTRIALS.GOV IDENTIFIER

NCT00911508.

Association Between Age and Outcomes of Catheter Ablation Versus Medical Therapy for Atrial Fibrillation: Results From the CABANA Trial

BACKGROUND

Observational data suggest that catheter ablation may be safe and effective to treat younger and older patients with atrial fibrillation. No large, randomized trial has examined this issue. This report describes outcomes according to age at entry in the CABANA trial (Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation).

METHODS

Patients with atrial fibrillation ≥65 years of age, or <65 with ≥1 risk factor for stroke, were randomly assigned to catheter ablation versus drug therapy. The primary outcome was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Secondary outcomes included all-cause mortality, the composite of mortality or cardiovascular hospitalization, and recurrence of atrial fibrillation. Treatment effect estimates were adjusted for baseline covariables using proportional hazards regression models.

RESULTS

Of 2204 patients randomly assigned in CABANA, 766 (34.8%) were <65 years of age, 1130 (51.3%) were 65 to 74 years of age, and 308 (14.0%) were ≥75 years of age. Catheter ablation was associated with a 43% reduction in the primary outcome for patients <65 years of age (adjusted hazard ratio [aHR], 0.57 [95% CI, 0.30-1.09]), a 21% reduction for 65 to 74 years of age (aHR, 0.79 [95% CI, 0.54-1.16]), and an indeterminate effect for age ≥75 years of age (aHR, 1.39 [95% CI, 0.75-2.58]). Four-year event rates for ablation versus drug therapy across age groups, respectively, were 3.2% versus 7.8%, 7.8% versus 9.6%, and 14.8% versus 9.0%. For every 10-year increase in age, the primary outcome aHR increased (ie, less favorable to ablation) an average of 27% (interaction P value=0.215). A similar pattern was seen with all-cause mortality: for every 10-year increase in age, the aHR increased an average of 46% (interaction P value=0.111). Atrial fibrillation recurrence rates were lower with ablation than with drug therapy across age subgroups (aHR 0.47, 0.58, and 0.49, respectively). Treatment-related complications were infrequent for both arms (<3%) regardless of age.

CONCLUSIONS

We found age-based variations in clinical outcomes for catheter ablation compared with drug therapy, with the largest relative and absolute benefits of catheter ablation in younger patients. No prognostic benefits for ablation were seen in the oldest patients. No differences were found by age in treatment-related complications or in the relative effectiveness of catheter ablation in preventing recurrent atrial arrhythmias.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT00911508.

Renal function and coronary bypass surgery in patients with ischemic heart failure

OBJECTIVE

Chronic kidney disease is a known risk factor in cardiovascular disease, but its influence on treatment effect of bypass surgery remains unclear. We assessed the influence of chronic kidney disease on 10-year mortality and cardiovascular outcomes in patients with ischemic heart failure treated with medical therapy (medical treatment) with or without coronary artery bypass grafting.

METHODS

We calculated the baseline estimated glomerular filtration rate (Chronic Kidney Disease Epidemiology Collaboration formula, chronic kidney disease stages 1-5) from 1209 patients randomized to medical treatment or coronary artery bypass grafting in the Surgical Treatment for IsChemic Heart failure trial and assessed its effect on outcome.

RESULTS

In the overall Surgical Treatment for IsChemic Heart failure cohort, patients with chronic kidney disease stages 3 to 5 were older than those with stages 1 and 2 (66-71 years vs 54-59 years) and had more comorbidities. Multivariable modeling revealed an inverse association between estimated glomerular filtration rate and risk of death, cardiovascular death, or cardiovascular rehospitalization (all P < .001, but not for stroke, P = .697). Baseline characteristics of the 2 treatment arms were equal for each chronic kidney disease stage. There were significant improvements in death or cardiovascular rehospitalization with coronary artery bypass grafting (stage 1: hazard ratio, 0.71; confidence interval, 0.53-0.96, P = .02; stage 2: hazard ratio, 0.71; confidence interval, 0.59-0.84, P < .0001; stage 3: hazard ratio, 0.76; confidence interval, 0.53-0.96, P = .03). These data were inconclusive in stages 4 and 5 for insufficient patient numbers (N = 28). There was no significant interaction of estimated glomerular filtration rate with the treatment effect of coronary artery bypass grafting (P = .25 for death and P = .54 for death or cardiovascular rehospitalization).

CONCLUSIONS

Chronic kidney disease is an independent risk factor for mortality in patients with ischemic heart failure with or without coronary artery bypass grafting. However, mild to moderate chronic kidney disease does not appear to influence long-term treatment effects of coronary artery bypass grafting.

Endothelial-T cell crosstalk contributes to vascular injury in fatty liver disease

 

Cardiovascular complications are often the fundamental causes of death in non-alcoholic fatty liver disease (NAFLD) patients. While there are known systemic mediators in NAFLD that may induce vascular inflammation, the mechanism of endothelial dysfunction remain understudied. In this work, we harnessed the replicative potential of blood outgrowth endothelial cells (BOECs) to develop personalized cell lines from NAFLD patients and healthy controls. Our transcriptomic analysis showed that the top interactome network enriched in NAFLD BOECs comprised of several C-C and C-X-C chemokine ligands involved in immune cell chemotaxis. We previously reported T cell infiltration in mouse model of non-alcoholic steatohepatitis, and here, we confirmed enhanced endothelial chemokine signatures in arterial histological sections. To elucidate endothelial-immune crosstalk, we performed single-cell analysis on human peripheral blood mononuclear cells and found T cell intensification in NAFLD patients compared to healthy controls. Our immunoprofiling by flow cytometry further revealed that NAFLD patients possessed higher levels CD8+ memory cells. Functionally, T cells, instead of monocytes, adhered more pronouncedly to NAFLD BOECs. In evaluating the CXCL12-CXCR4 axis in chemotaxis, CXCR4 antagonist (AMD3100) substantially modulated the migration of patient-derived CD8+ T cells towards NAFLD BOECs, which was not observed in healthy endothelial-T cell chemotaxis coculture. Finally, we validated NAFLD-associated endothelial dysfunction by enumerating two folds more circulating endothelial cells, a biomarker of vascular injury, in the blood samples of NAFLD patients than healthy controls. Our work provides insights for translation to restore blood vessel health and potentially mitigate adverse vascular events in NAFLD.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Industrial Alignment Fund Pre-Positioning grant from the Agency for Science, Technology and Research, Singapore Endothelial-T cell crosstalk in NAFLD

Treatment-Related Changes in Left Atrial Structure in Atrial Fibrillation: Findings From the CABANA Imaging Substudy

[Figure: see text].

Ablation Versus Drug Therapy for Atrial Fibrillation in Heart Failure: Results From the CABANA Trial

BACKGROUND

In patients with heart failure and atrial fibrillation (AF), several clinical trials have reported improved outcomes, including freedom from AF recurrence, quality of life, and survival, with catheter ablation. This article describes the treatment-related outcomes of the AF patients with heart failure enrolled in the CABANA trial (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation).

METHODS

The CABANA trial randomized 2204 patients with AF who were ≥65 years old or <65 years old with ≥1 risk factor for stroke at 126 sites to ablation with pulmonary vein isolation or drug therapy including rate or rhythm control drugs. Of these, 778 (35%) had New York Heart Association class >II at baseline and form the subject of this article. The CABANA trial's primary end point was a composite of death, disabling stroke, serious bleeding, or cardiac arrest.

RESULTS

Of the 778 patients with heart failure enrolled in CABANA, 378 were assigned to ablation and 400 to drug therapy. Ejection fraction at baseline was available for 571 patients (73.0%), and 9.3% of these had an ejection fraction <40%, whereas 11.7% had ejection fractions between 40% and 50%. In the intention-to-treat analysis, the ablation arm had a 36% relative reduction in the primary composite end point (hazard ratio, 0.64 [95% CI, 0.41-0.99]) and a 43% relative reduction in all-cause mortality (hazard ratio, 0.57 [95% CI, 0.33-0.96]) compared with drug therapy alone over a median follow-up of 48.5 months. AF recurrence was decreased with ablation (hazard ratio, 0.56 [95% CI, 0.42-0.74]). The adjusted mean difference for the AFEQT (Atrial Fibrillation Effect on Quality of Life) summary score averaged over the entire 60-month follow-up was 5.0 points, favoring the ablation arm (95% CI, 2.5-7.4 points), and the MAFSI (Mayo Atrial Fibrillation-Specific Symptom Inventory) frequency score difference was -2.0 points, favoring ablation (95% CI, -2.9 to -1.2).

CONCLUSIONS

In patients with AF enrolled in the CABANA trial who had clinically diagnosed stable heart failure at trial entry, catheter ablation produced clinically important improvements in survival, freedom from AF recurrence, and quality of life relative to drug therapy. These results, obtained in a cohort most of whom had preserved left ventricular function, require independent trial verification. Registration: URL: https://www.clinicaltrials.gov/ct2/show/NCT00911508; Unique identifier: NCT0091150.

Admission triage tool for adult intensive care unit admission in Hong Kong during the COVID-19 outbreak

Intensive care is expensive, and the numbers of intensive care unit (ICU) beds and trained specialist medical staff able to provide services in Hong Kong are limited. The most recent increase in coronavirus disease 2019 (COVID-19) infections over July to August 2020 resulted in more than 100 new cases per day for a prolonged period. The increased numbers of critically ill patients requiring ICU admission posed a capacity challenge to ICUs across the territory, and it may be reasonably anticipated that should a substantially larger outbreak occur, ICU services will be overwhelmed. Therefore, a transparent and fair prioritisation process for decisions regarding patient ICU admission is urgently required. This triage tool is built on the foundation of the existing guidelines and framework for admission, discharge, and triage that inform routine clinical practice in Hospital Authority ICUs, with the aim of achieving the greatest benefit for the greatest number of patients from the available ICU resources. This COVID-19 Crisis Triage Tool is expected to provide structured guidance to frontline doctors on how to make triage decisions should ICU resources become overwhelmed by patients requiring ICU care, particularly during the current COVID-19 pandemic. The triage tool takes the form of a detailed decision aid algorithm based on a combination of established prognostic scores, and it should increase objectivity and transparency in triage decision making and enhance decision-making consistency between doctors within and across ICUs in Hong Kong. However, it remains an aid rather than a complete substitute for the carefully considered judgement of an experienced intensive care clinician.

Long-Term Outcomes of Implantable Cardioverter-Defibrillator Therapy in the SCD-HeFT

BACKGROUND

The SCD-HeFT (Sudden Cardiac Death in Heart Failure Trial) randomized 2,521 patients with moderate heart failure (HF) to amiodarone, placebo drug, or implantable cardioverter-defibrillator (ICD) therapy. Original trial follow-up ended October 31, 2003. Over a median 45.5-month follow-up, amiodarone, compared with placebo, did not affect survival, whereas randomization to an ICD significantly decreased all-cause mortality by 23%.

OBJECTIVES

This study sought to describe the extended treatment group survival of the SCD-HeFT cohort.

METHODS

Mortality outcomes for the 1,855 patients alive at the end of the SCD-HeFT trial were collected between 2010 and 2011. These data were combined with the 666 deaths from the original study to compare long-term outcomes overall and for key pre-specified subgroups.

RESULTS

Median (25th to 75th percentiles) follow-up was 11.0 (10.0 to 12.2) years. On the basis of intention-to-treat analysis, the ICD group had overall survival benefit versus placebo drug (hazard ratio [HR]: 0.87; 95% confidence interval [CI]: 0.76 to 0.98; p = 0.028). When treatment benefit was examined as a function of time from randomization, attenuation of the ICD benefit was observed after 6 years (p value for the interaction = 0.0015). Subgroup analysis revealed long-term ICD benefit varied according to HF etiology and New York Heart Association (NYHA) functional class: ischemic HF HR: 0.81; 95% CI: 0.69 to 0.95; p = 0.009; nonischemic HF HR: 0.97; 95% CI: 0.79 to 1.20; p = 0.802; NYHA functional class II HR: 0.76; 95% CI: 0.65 to 0.90; p = 0.001; NYHA functional class III HR: 1.06; 95% CI: 0.86 to 1.31; p = 0.575.

CONCLUSIONS

Follow-up of SCD-HeFT patients to 11 years demonstrated heterogenous treatment-related patterns of long-term survival with ICD benefit most evident at 11 years for ischemic HF patients and for those with NYHA functional class II symptoms at trial enrollment. (SCD-HeFT 10 Year Follow-up [SCD-HeFT10 Yr]; NCT01058837).

Possible differential benefits of edetate disodium in post-myocardial infarction patients with diabetes treated with different hypoglycemic strategies in the Trial to Assess Chelation Therapy (TACT)

BACKGROUND

The NIH-funded Trial to Assess Chelation Therapy (TACT) randomized 1708 stable patients age ≥50 who were ≥6 months post myocardial infarction to 40 infusions of an edetate disodium-based regimen or placebo. In 633 patients with diabetes, edetate disodium significantly reduced the primary composite endpoint of mortality, recurrent myocardial infarction, stroke, coronary revascularization, or hospitalization for angina (hazard ratio [HR] 0.59, 95% confidence interval [CI] 0.44-0.79, p < 0.001). The principal secondary endpoint of a composite of cardiovascular death, myocardial infarction, or stroke was also reduced (HR 0.60, 95% CI 0.39-0.91, p = 0.017). It is unknown if the treatment effect differs by diabetes therapy.

METHODS

We grouped the subset of 633 patients with diabetes according to glucose-lowering therapy at time of randomization. The log-rank test was used to compare active therapy versus placebo. All treatment comparisons were performed using 2-sided significance tests at the significance level of 0.05 and were as randomized. Relative risks were expressed as HR with associated 95% CI, calculated using the Cox proportional hazards model.

RESULTS

There were 162 (25.7%) patients treated with insulin; 301 (47.5%) with oral hypoglycemics only; and 170 (26.8%) receiving no pharmacologic treatment for diabetes. Patients on insulin reached the primary endpoint more frequently than patients on no pharmacologic treatment [61 (38%) vs 49 (29%) (HR 1.56, 95% CI 1.07-2.27, p = 0.022)] or oral hypoglycemics [61 (38%) vs 87 (29%) (HR 1.46, 1.05-2.03, p = 0.024)]. The primary endpoint occurred less frequently with edetate disodium based therapy versus placebo in patients on insulin [19 (26%) vs 42 (48%) (HR 0.42, 95% CI 0.25-0.74, log-rank p = 0.002)], marginally in patients on oral hypoglycemics [38 (25%) vs 49 (34%) (HR 0.66, 95% CI 0.43-1.01, log-rank p = 0.041)], and no significant difference in patients not treated with a pharmacologic therapy [23 (25%) vs 26 (34%) (HR 0.69, 95% CI 0.39-1.20, log-rank p = 0.225)]. The interaction between randomized intravenous treatment and type of diabetes therapy was not statistically significant (p = 0.203).

CONCLUSIONS

Edetate disodium treatment in stable, post-myocardial infarction patients with diabetes suggests that patients on insulin therapy at baseline may accrue the greatest benefit.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov identifier: http://clinicaltrials.gov/ct2/show/NCT00044213?term=TACT&rank=7 identifier Trial to Assess Chelation Therapy (TACT), NCT00044213.

Recurrence of Atrial Fibrillation After Catheter Ablation or Antiarrhythmic Drug Therapy in the CABANA Trial

BACKGROUND

The CABANA (Catheter Ablation Versus Antiarrhythmic Drug Therapy for Atrial Fibrillation) trial randomized 2,204 patients with atrial fibrillation (AF) to catheter ablation or drug therapy. Analysis by intention-to-treat showed a nonsignificant 14% relative reduction in the primary outcome of death, disabling stroke, serious bleeding, or cardiac arrest.

OBJECTIVES

The purpose of this study was to assess recurrence of AF in the CABANA trial.

METHODS

The authors prospectively studied CABANA patients using a proprietary electrocardiogram recording monitor for symptom-activated and 24-h AF auto detection. The AF recurrence endpoint was any post-90-day blanking atrial tachyarrhythmias lasting 30 s or longer. Biannual 96-h Holter monitoring was used to assess AF burden. Patients who used the CABANA monitors and provided 90-day post-blanking recordings qualified for this analysis (n = 1,240; 56% of CABANA population). Treatment comparisons were performed using a modified intention-to-treat approach.

RESULTS

Median age of the 1,240 patients was 68 years, 34.4% were women, and AF was paroxysmal in 43.0%. Over 60 months of follow-up, first recurrence of any symptomatic or asymptomatic AF (hazard ratio: 0.52; 95% confidence interval: 0.45 to 0.60; p < 0.001) or first symptomatic-only AF (hazard ratio: 0.49; 95% confidence interval: 0.39 to 0.61; p < 0.001) were both significantly reduced in the catheter ablation group. Baseline Holter AF burden in both treatment groups was 48%. At 12 months, AF burden in ablation patients averaged 6.3%, and in drug-therapy patients, 14.4%. AF burden was significantly less in catheter ablation compared with drug-therapy patients across the 5-year follow-up (p < 0.001). These findings were not sensitive to the baseline pattern of AF.

CONCLUSIONS

Catheter ablation was effective in reducing recurrence of any AF by 48% and symptomatic AF by 51% compared with drug therapy over 5 years of follow-up. Furthermore, AF burden was also significantly reduced in catheter ablation patients, regardless of their baseline AF type. (Catheter Ablation vs Anti-arrhythmic Drug Therapy for Atrial Fibrillation Trial [CABANA]; NCT00911508).

Incremental prognostic value of echocardiography of left ventricular remodeling and diastolic function in STICH trial

Aims

We sought to determine which echocardiographic markers of left ventricular (LV) remodeling and diastolic dysfunction can contribute as incremental and independent prognostic information in addition to current clinical risk markers of ischemic LV systolic dysfunction in the Surgical Treatment for Ischemic Heart Failure (STICH) trial.

Methods and results

The cohort consisted of 1511 of 2136 patients in STICH for whom baseline transmitral Doppler (E/A ratio) could be measured by an echocardiographic core laboratory blinded to treatment and outcomes, and prognostic value of echocardiographic variables was determined by a Cox regression model. E/A ratio was the most significant predictor of mortality amongst diastolic variables with lowest mortality for E/A closest 0.8, although mortality was consistently low for E/A 0.6 to 1.0. Mortality increased for E/A < 0.6 and > 1.0 up to approximately 2.3, beyond which there was no further increase in risk. Larger LV end-systolic volume index (LVESVI) and E/A < 0.6 and > 1.0 had incremental negative effects on mortality when added to a clinical multivariable model, where creatinine, LVESVI, age, and E/A ratio accounted for 74% of the prognostic information for predicting risk. LVESVI and E/A ratio were stronger predictors of prognosis than New York Heart Association functional class, anemia, diabetes, history of atrial fibrillation, and stroke.

Conclusions

Echocardiographic markers of advanced LV remodeling and diastolic dysfunction added incremental prognostic value to current clinical risk markers. LVESVI and E/A ratio outperformed other markers and should be considered as standard in assessing risks in ischemic heart failure. E/A closest to 0.8 was the most optimal filling pattern.

Differential Outcomes With Edetate Disodium-Based Treatment Among Stable Post Anterior vs. Non-Anterior Myocardial Infarction Patients

BACKGROUND

The Trial to Assess Chelation Therapy (TACT) found that chelation therapy significantly reduced clinical events in patients with a history of myocardial infarction (MI). The initial report of TACT included the observation of an interaction between edetate disodium infusions and MI location, as well as diabetes. Thus, we examined in greater detail the effect of edetate disodium chelation therapy as a function of MI location and diabetes.

METHODS

Patients (n = 1708) at least 6 weeks post-MI and age ≥ 50 were randomized to receive 40 infusions of a 500 mL chelation solution or placebo (median follow-up 55 months). The effect of edetate disodium on the primary outcome (all-cause mortality, MI, stroke, hospitalization for angina, or coronary revascularization) was assessed as a function of MI location using log-rank test and Cox regression model, adjusting for other prognostic variables.

RESULTS

Among patients with post anterior MI (n = 674), chelation was associated with a lower risk of the primary endpoint (HR 0.63, 95% CI 0.47-0.86, p = 0.003) among anterior MI patients, but not in post non-anterior MI (n = 1034) patients (HR 0.96, 95% CI 0.77-1.20, p = 0.702) (p-for-interaction = 0.032). The point estimates for each component of the primary endpoint favored chelation therapy. The differing treatment effect in patients with post anterior vs. non-anterior MI was consistent among patients with or without diabetes and remained significant after adjusting for other prognostic variables (p < 0.01).

CONCLUSIONS

Edetate disodium infusions reduced the risk of cardiovascular events among patients with a prior anterior MI. Future studies should focus on replicating these results and understanding the mechanisms of benefit.

The association between blood pressure and long-term outcomes of patients with ischaemic cardiomyopathy with and without surgical revascularization: an analysis of the STICH trial

Aims

Hypertension (HTN) is a well-known contributor to cardiovascular disease, including heart failure (HF) and coronary artery disease, and is the leading risk factor for premature death world-wide. A J- or U-shaped relationship has been suggested between blood pressure (BP) and clinical outcomes in different studies. However, there is little information about the significance of BP on the outcomes of patients with coronary artery disease and left ventricular dysfunction. This study aimed to determine the relationship between BP and mortality outcomes in patients with ischaemic cardiomyopathy.

Methods and results

The influence of BP during a median follow-up of 9.8 years was studied in a total of 1212 patients with ejection fraction ≤35% and coronary disease amenable to coronary artery bypass grafting (CABG) who were randomized to CABG or medical therapy alone (MED) in the STICH (Surgical Treatment for Ischaemic Heart Failure) trial. Landmark analyses were performed starting at 1, 2, 3, 4, and 5 years after randomization, in which previous systolic BP values were averaged and related to subsequent mortality through the end of follow-up with a median of 9.8 years. Neither a previous history of HTN nor baseline BP had any significant influence on long-term mortality outcomes, nor did they have a significant interaction with MED or CABG treatment. The landmark analyses showed a progressive U-shaped relationship that became strongest at 5 years (χ2 and P-values: 7.08, P = 0.069; 8.72, P = 0.033; 9.86; P = 0.020; 8.31, P = 0.040; 14.52, P = 0.002; at 1, 2, 3, 4, and 5-year landmark analyses, respectively). The relationship between diastolic BP (DBP) and outcomes was similar. The most favourable outcomes were observed in the SBP range 120-130, and DBP 75-85 mmHg, whereas lower and higher BP were associated with worse outcomes. There were no differences in BP-lowering medications between groups.

Conclusion

A strong U-shaped relationship between BP and mortality outcomes was evident in ischaemic HF patients. The results imply that the optimal SBP might be in the range 120-130 mmHg after intervention, and possibly be subject to pharmacologic action regarding high BP. Further, low BP was a marker of poor outcomes that might require other interactions and treatment strategies.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00023595.

Discordances between predicted and actual risk in obese patients with suspected cardiac ischaemia

OBJECTIVES

To test the relationship between increasing severity of obesity, calculated risk and observed outcomes.

METHODS

Patients with symptoms suggestive of coronary artery disease (CAD) (n=10 003) were stratified according to body mass index (BMI). We compared risk factors, pooled risk scores and physicians' perception of risk. Cox regression tested the association between BMI and (1) presence of obstructive CAD and (2) composite clinical endpoints (death, cardiovascular death, unstable angina hospitalisation and myocardial infarction).

RESULTS

BMI was ≥30 kg/m² in 48% of patients and ≥35 in 20%. Increasingly obese patients were younger, female and non-smoking but with higher prevalence of hypertension, diabetes, black race and sedentary lifestyle. Pooled risk estimates of CAD were highest in those with mid-range BMI. In contrast, physicians' estimation of the likelihood of significant CAD based on clinical impression increased progressively with BMI. For a 10% increase in the Diamond-Forrester probability of CAD, the adjusted OR for obstructive CAD was 1.5 (95% CI 1.4 to 1.5) in patients with BMI <35, but only 1.2 (95% CI 1.1 to 1.3) in those with BMI ≥35 (interaction p<0.001). Framingham Risk Score increased across increasing BMI categories. However, there was a strong and consistent inverse relationship between degree of obesity and all three composite clinical endpoints over a median 25 months of follow-up.

CONCLUSIONS

Despite perceptions of higher risk and higher risk scores, increasingly obese patients had obstructive CAD less frequently than predicted and had fewer adverse clinical outcomes. There is a need for risk assessment tools and guidelines that account for obesity.

TRIAL REGISTRATION NUMBER

NCT01174550.

P2832Outcomes of catheter ablation for atrial fibrillation based on sex: data from the cabana trial

Background

Sex-specific outcomes may differ amongst patients receiving catheter ablation for atrial fibrillation (AF).

Purpose

Assess sex-specific outcomes in the patients randomized to catheter ablation or drug therapy in CABANA.

Methods

CABANA randomized 2204 pts with AF to catheter ablation or drug therapy (rate/rhythm-control). The outcomes of combined death, disabling stroke, severe bleeding, or cardiac arrest (intention to treat-ITT) or all-cause death were not different. But, ablation significantly improved combined death or CV hospitalization. This analysis compares clinical characteristics by sex and determines sex-specific hazard ratios based on a comparison of ablation vs drug therapy.

Results

Females were 37.3% of ablation and 37.0% of drug therapy patients. Females were older, more often white race, had less CAD, or sleep apnea, but had higher NYHA Class, higher CHA2DS2VASc, and more often had paroxysmal (v. persistent) AF, and prior AF hospitalization. (Table) HTN, CVA and diabetes were the same (Table).

For the CABANA primary endpoint, an ITT comparison of ablation vs. drug therapy, showed a female hazard ratio (HR) of 1.14 (95% confidence interval (CI) 0.70–1.86), and a male HR of 0.74, (95% CI 0.52–1.06). For all-cause mortality, the female HR was 0.75 (95% CI 0.41–1.40) and male HR was 0.91 (95% CI 0.59–1.40) and for all-cause mortality or CV hospitalization, the female HR was 0.90 (95% CI 0.75–1.09) and male HR was 0.79 (95% CI 0.69–0.92). All interaction p values were non-significant.

Recurrent AF (post 90-day blanking) was significantly reduced for both females and males: female HR 0.64 (95% CI 0.51–0.82), male HR 0.46 95% CI 0.39–0.56), p=0.035

Clinical Characteristics and Outcomes Baseline Characteristics Female (N=818) Male (N=1385) p-value Age: Median (Q1, Q3) 69 (65, 74) 66 (60, 71) <0.001 White 766 (93.9%) 1259 (91.0%) 0.015 CAD 92 (11.2%) 332 (24.0%) <0.001 NYHA ≥II 345 (42.4%) 433 (31.5%) <0.001 Sleep apnea 136 (16.6%) 372 (26.9%) <0.001 CHA2DS2-VASc: Median (Q1, Q3) 3 (3, 4) 2 (1, 3) <0.001 Paroxysmal AF 406 (49.6%) 540 (39.0%) <0.001 Persistent AF 412 (50.4%) 845 (61.0%) AF Hospitalization 353 (43.2%) 521 (37.7%) 0.011

Conclusion

Significant sex-specific outcomes differences were not observed. Sex should not be used as a determining factor in selecting patients for AF therapy.

Acknowledgement/Funding

NIH, St Jude Medical Foundation and Corporation, Biosense Webster Inc., Medtronic Corporation, and Boston Scientific Corporation

CABG Improves Outcomes in Patients With Ischemic Cardiomyopathy: 10-Year Follow-Up of the STICH Trial

OBJECTIVES

The authors investigated the impact of coronary artery bypass grafting (CABG) on first and recurrent hospitalization in this population.

BACKGROUND

In the STICH (Surgical Treatment for Ischemic Heart Failure) trial, CABG reduced all-cause death and hospitalization in patients with and ischemic cardiomyopathy and left ventricular ejection fraction <35%.

METHODS

A total of 1,212 patients were randomized (610 to CABG + optimal medical therapy [CABG] and 602 to optimal medical therapy alone [MED] alone) and followed for a median of 9.8 years. All-cause and cause-specific hospitalizations were analyzed as time-to-first-event and as recurrent event analysis.

RESULTS

Of the 1,212 patients, 757 died (62.4%) and 732 (60.4%) were hospitalized at least once, for a total of 2,549 total all-cause hospitalizations. Most hospitalizations (66.2%) were for cardiovascular causes, of which approximately one-half (907 or 52.9%) were for heart failure. More than 70% of all hospitalizations (1,817 or 71.3%) were recurrent events. The CABG group experienced fewer all-cause hospitalizations in the time-to-first-event (349 CABG vs. 383 MED, adjusted hazard ratio [HR]: 0.85; 95% confidence interval [CI]: 0.74 to 0.98; p = 0.03) and in recurrent event analyses (1,199 CABG vs. 1,350 MED, HR: 0.78, 95% CI: 0.65 to 0.94; p < 0.001). This was driven by fewer total cardiovascular (CV) hospitalizations (744 vs. 968; p < 0.001, adjusted HR: 0.66, 95% CI: 0.55 to 0.81; p = 0.001), the majority of which were due to HF (395 vs. 512; p < 0.001, adjusted HR: 0.68, 95% CI: 0.52-0.89; p = 0.005). We did not observe a difference in non-CV events.

CONCLUSIONS

CABG reduces all-cause, CV, and HF hospitalizations in time-to-first-event and recurrent event analyses. (Comparison of Surgical and Medical Treatment for Congestive Heart Failure and Coronary Artery Disease [STICH]; NCT00023595).

P4427Cardiovascular outcomes among runners of a marathon race - a 17 years' experience

Introduction

Over the past 17 years (2002–2018), 898,831 people participated in the Hong Kong Standard Chartered Marathon (HKSCM).

Purpose

We aim to study the incidence of marathon-related sudden cardiac arrest (SCA) and non-fatal myocardial injury (NFMI).

Methods

All the HKSCM related admissions between 2002 and 2017 were retrieved from the accident and emergency department admission records. We reviewed the data of HKSCM runners admitted for SCA and NFMI.

Results

Fourteen and thirty-nine runners were admitted for SCA (Mean age 38±13 years-old, 12 men) and NFMI (Mean age 42±12 years-old; 34 men) respectively.

Among the SCA runners, the arrest rhythms could not be retrieved in 3 cases. In the remaining 11 SCA runners, the arrest rhythms were ventricular fibrillation (VF) (N=6), pulseless-electrical activity (PEA) (N=3), and asystole (N=2). Nine of the 14 SCA runners were successfully resuscitated. Only 2 out of the 14 SCA runners had significant atherosclerotic coronary artery disease (CAD) requiring coronary angioplasty. Among the SCA runners, the etiologies of cardiac arrest were myocardial infarction (MI) (N=2), ischemic cardiomyopathy with VF (N=1), idiopathic VF (N=3), malignant coronary anomaly (N=1), and idiopathic (N=5). Percutaneous coronary intervention (PCI) was performed in 2 SCA runner with MI. Implantable cardioverter-defibrillators were implanted in 1 resuscitated runner with VF. Postmortem examination of the 3 deceased runners showed significant CAD in two and was unrevealing in one.

Among the 39 NFMI runners, coronary angiograms (CAG) or CT coronary angiogram were performed in 14 cases (36%), which showed minor CAD or unremarkable findings in 7 runners, and significant CAD in 7 runners. PCI and coronary artery bypass were performed in 5 and 2 NFMI runners respectively. Only 8 out of 39 NFMI runners reported chest pain. Significant ischemic ECG changes were detected in 9 out of 39 NFMI runners. Invasive CAGs were not performed in the remaining NFMI runners due to low pre-test likelihood of CAD and normal non-invasive test results.

Conclusions

The incidence of SCA and mortality among HKSCM runners was 1.56 per 100,000 and 0.56 per 100,000 respectively. The incidence of NFMI was 4.3 per 100,000. Coronary artery disease, coronary anomaly and idiopathic VF were the commonest etiologies of SCA.

484Impact of AF type on the outcome of atrial fibrillation ablation: insights from the CABANA trial

Background

Prior studies suggest that catheter ablation (ABL) for atrial fibrillation (AF) is a treatment option for patients (pts) with paroxysmal AF (PAF). Pts with persistent (Per) or long-standing persistent (LSP) were routinely excluded from most ABL based clinical trials. The effectiveness of ABL compared to drug therapy (MED) in relation to underlying AF type has not been evaluated in a large randomized clinical trial.

Objective

To assess the impact of AF type on clinical outcomes of ABL vs. MED in pts with AF.

Methods

The CABANA trial randomized 2204 pts with AF at 126 sites worldwide to ABL vs. MED with rate or rhythm control drugs. The primary endpoint was a composite of death, disabling stroke, severe bleeding, or cardiac arrest. Key secondary endpoints included mortality and recurrence of AF. Outcomes of ABL vs. MED were compared within subgroups defined by AF type using Intention-to-Treat (ITT) analyses.

Results

Of the 2204 pts, 946 had PAF, 1042 had Per and 215 presented with LSP. There were baseline differences among AF types in age, gender, HTN, LVH, CHF and NYHA Class. For the primary endpoint, there were no significant differences between ABL and MED in pts with PAF (hazard ratio (HR) 0.82; 95% confidence interval (CI) 0.51, 1.31), Per (HR 0.87; 95% CI 0.59, 1.28), or LSP (HR 1.01, 95% CI 0.39, 2.61). Likewise, there were no significant treatment differences in mortality; PAF (HR 0.84; 95% CI 0.46, 1.52), Per (HR 0.90; 95% CI 0.56, 1.46) and LSP (HR 0.67, 95% CI 0.23, 1.94). Post-blanking AF (time to first recurrence) was significantly reduced by ABL compared to MED across all AF types (PAF by 51%), (Per by 47%) and (LSP by 36%).

Clinical Characteristics and Outcomes Clinical Outcomes Comparing ABL vs. MED (HR and 95% CI) Interaction p-value Primary Endpoint 0.82 (0.51, 1.31) 0.87 (0.59, 1.28) 1.01 (0.39, 2.61) 0.925 Mortality 0.84 (0.46, 1.52) 0.90 (0.56, 1.46) 0.67 (0.23, 1.94) 0.881 Recurrent AF 0.49 (0.38, 0.62) 0.53 (0.43, 0.65) 0.64 (0.41, 1.01) 0.564

Conclusion

Pts with LSP have a lower proportion of women, and a higher proportion with manifestations of heart failure despite lower CHA2DS2VASc scores. By ITT analysis, there is no significant effect of ABL compared to MED in the primary endpoint or mortality in any AF group. However, ABL is more effective than MED for reducing recurrences of AF regardless of AF type, but with a greater effect in PAF vs Per vs LSP.

Acknowledgement/Funding

NIH, St Jude Medical Foundation and Corporation, Biosense Webster Inc., Medtronic Corporation, and Boston Scientific Corporation

Use of High-Risk Coronary Atherosclerotic Plaque Detection for Risk Stratification of Patients With Stable Chest Pain: A Secondary Analysis of the PROMISE Randomized Clinical Trial

Importance

Coronary computed tomographic angiography (coronary CTA) can characterize coronary artery disease, including high-risk plaque. A noninvasive method of identifying high-risk plaque before major adverse cardiovascular events (MACE) could provide practice-changing optimizations in coronary artery disease care.

Objective

To determine whether high-risk plaque detected by coronary CTA was associated with incident MACE independently of significant stenosis (SS) and cardiovascular risk factors.

Design, Setting, and Participants

This prespecified nested observational cohort study was part of the Prospective Multicenter Imaging Study for Evaluation of Chest Pain (PROMISE) trial. All stable, symptomatic outpatients in this trial who required noninvasive cardiovascular testing and received coronary CTA were included and followed up for a median of 25 months.

Exposures

Core laboratory assessment of coronary CTA for SS and high-risk plaque (eg, positive remodeling, low computed tomographic attenuation, or napkin-ring sign).

Main Outcomes and Measures

The primary end point was an adjudicated composite of MACE (defined as death, myocardial infarction, or unstable angina).

Results

The study included 4415 patients, of whom 2296 (52%) were women, with a mean age of 60.5 years, a median atherosclerotic cardiovascular disease (ASCVD) risk score of 11, and a MACE rate of 3% (131 events). A total of 676 patients (15.3%) had high-risk plaques, and 276 (6.3%) had SS. The presence of high-risk plaque was associated with a higher MACE rate (6.4% vs 2.4%; hazard ratio, 2.73; 95% CI, 1.89-3.93). This association persisted after adjustment for ASCVD risk score and SS (adjusted hazard ratio [aHR], 1.72; 95% CI, 1.13-2.62). Adding high-risk plaque to the ASCVD risk score and SS assessment led to a significant continuous net reclassification improvement (0.34; 95% CI, 0.02-0.51). Presence of high-risk plaque increased MACE risk among patients with nonobstructive coronary artery disease relative to patients without high-risk plaque (aHR, 4.31 vs 2.64; 95% CI, 2.25-8.26 vs 1.49-4.69). There were no significant differences in MACE in patients with SS and high-risk plaque as opposed to those with SS but not high-risk plaque (aHR, 8.68 vs. 9.31; 95% CI, 4.25-17.73 vs 4.21-20.61). High-risk plaque was a stronger predictor of MACE in women (aHR, 2.41; 95% CI, 1.25-4.64) vs men (aHR, 1.40; 95% CI, 0.81-2.39) and younger patients (aHR, 2.33; 95% CI, 1.20-4.51) vs older ones (aHR, 1.36; 95% CI, 0.77-2.39).

Conclusions and Relevance

High-risk plaque found by coronary CTA was associated with a future MACE in a large US population of outpatients with stable chest pain. High-risk plaque may be an additional risk stratification tool, especially in patients with nonobstructive coronary artery disease, younger patients, and women. The importance of findings is limited by low absolute MACE rates and low positive predictive value of high-risk plaque.

Trial Registration

clinicaltrials.gov Indentifier: NCT01174550.

Myocardial Viability and Long-Term Outcomes in Ischemic Cardiomyopathy

BACKGROUND

The role of assessment of myocardial viability in identifying patients with ischemic cardiomyopathy who might benefit from surgical revascularization remains controversial. Furthermore, although improvement in left ventricular function is one of the goals of revascularization, its relationship to subsequent outcomes is unclear.

METHODS

Among 601 patients who had coronary artery disease that was amenable to coronary-artery bypass grafting (CABG) and who had a left ventricular ejection fraction of 35% or lower, we prospectively assessed myocardial viability using single-photon-emission computed tomography, dobutamine echocardiography, or both. Patients were randomly assigned to undergo CABG and receive medical therapy or to receive medical therapy alone. Left ventricular ejection fraction was measured at baseline and after 4 months of follow-up in 318 patients. The primary end point was death from any cause. The median duration of follow-up was 10.4 years.

RESULTS

CABG plus medical therapy was associated with a lower incidence of death from any cause than medical therapy alone (182 deaths among 298 patients in the CABG group vs. 209 deaths among 303 patients in the medical-therapy group; adjusted hazard ratio, 0.73; 95% confidence interval, 0.60 to 0.90). However, no significant interaction was observed between the presence or absence of myocardial viability and the beneficial effect of CABG plus medical therapy over medical therapy alone (P = 0.34 for interaction). An increase in left ventricular ejection fraction was observed only among patients with myocardial viability, irrespective of treatment assignment. There was no association between changes in left ventricular ejection fraction and subsequent death.

CONCLUSIONS

The findings of this study do not support the concept that myocardial viability is associated with a long-term benefit of CABG in patients with ischemic cardiomyopathy. The presence of viable myocardium was associated with improvement in left ventricular systolic function, irrespective of treatment, but such improvement was not related to long-term survival. (Funded by the National Institutes of Health; STICH ClinicalTrials.gov number, NCT00023595.).

The effect of EDTA-based chelation on patients with diabetes and peripheral artery disease in the Trial to Assess Chelation Therapy (TACT)

OBJECTIVE

Approximately 1 in 7 US adults have diabetes; and over 60% of deaths in patients with diabetes have cardiac disease as a principal or contributing cause. Both coronary and peripheral artery disease (PAD) identify high-risk cohorts among patients with diabetes. We have previously demonstrated improved cardiovascular outcomes with edetate disodium-based chelation in post-MI patients with diabetes, enrolled in the Trial to Assess Chelation Therapy (TACT). In these analyses we further studied the effect size of patients with diabetes and severe disease in 2 vascular beds; coronaries, and lower extremity arteries. We questioned whether greater atherosclerotic burden would attenuate the observed beneficial effect of edetate disodium infusions.

RESEARCH DESIGN AND METHODS

The multicenter TACT used a double blind, placebo controlled, 2 × 2 factorial design with 1708 participants, randomly assigned to receive edetate disodium-based chelation, or placebo and high dose oral vitamins or placebo. There were 162 (9.5% of 1708) post-MI patients with a diagnosis of diabetes mellitus and PAD for this post hoc analysis. Patients received up to 40 double-blind intravenous infusions of edetate disodium-based chelation, or placebo. The composite primary endpoint of TACT consisted of death from any cause, myocardial infarction, stroke, coronary revascularization and hospitalization for angina.

RESULTS

The median age was 66 years, 15% female, 5% non-Caucasian, and BMI was 31. Insulin was used by 32% of patients. Active infusions significantly reduced the primary endpoint compared with placebo infusions (HR, 0.52; 95% CI, 0.30-0.92; P = 0.0069), with a 30% absolute risk reduction in the primary endpoint. There was a marked reduction in total mortality from 24% to 11%, although of borderline significance (P = 0.052).

CONCLUSION

Atherosclerotic disease in multiple vascular beds did not attenuate the beneficial effect of edetate disodium infusions in post MI patients with diabetes. Studies now in progress will prospectively test this post hoc finding.

Primary Prevention Implantable Cardioverter Defibrillators in Patients With Nonischemic Cardiomyopathy: A Meta-analysis

Importance

Conflicting data have emerged on the efficacy of implantable cardioverter defibrillators (ICDs) for primary prevention of sudden cardiac death (primary prevention ICDs) in patients with nonischemic cardiomyopathy.

Objective

To investigate the association of primary prevention ICDs with all-cause mortality in patients with nonischemic cardiomyopathy.

Data Sources

PubMed was searched from January 1, 2000, through October 31, 2016, for the terms implantable defibrillator OR implantable cardioverter defibrillator AND non-ischemic cardiomyopathy. Additional references were identified from bibliographies of pertinent articles and queries to experts in this field.

Study Selection

Inclusion criteria consisted of a randomized clinical trial design and comparison of the ICD with medical therapy (control) in at least 100 patients with nonischemic cardiomyopathy. In addition, studies had to report on all-cause mortality during a follow-up period of at least 12 months and be published in English. The search yielded 10 studies, of which only 1 met the inclusion criteria. A search of bibliographies of pertinent articles and queries of experts in this field led to 3 additional studies.

Data Extraction and Synthesis

The PRISMA guidelines were used to abstract data and assess data quality and validity. Data were pooled using fixed- and random-effects models.

Main Outcomes and Measures

The primary end point was all-cause mortality. Before data collection started, primary prevention ICDs were hypothesized to reduce all-cause mortality among patients with nonischemic cardiomyopathy.

Results

Four randomized clinical trials met the selection criteria and included 1874 unique patients; 937 were in the ICD group and 937 in the control group. Pooling data from these trials showed a significant reduction in all-cause mortality with an ICD (hazard ratio, 0.75; 95% CI, 0.61-0.93; P = .008; P = .87 for heterogeneity).

Conclusions and Relevance

Primary prevention ICDs are efficacious at reducing all-cause mortality among patients with nonischemic cardiomyopathy. These findings support professional guidelines that recommend the use of ICDs in such patients.

Identification of Patients With Stable Chest Pain Deriving Minimal Value From Noninvasive Testing: The PROMISE Minimal-Risk Tool, A Secondary Analysis of a Randomized Clinical Trial

Importance

Guidelines recommend noninvasive testing for patients with stable chest pain, although many subsequently have normal test results and no adverse clinical events.

Objective

To describe a risk tool developed to use only pretest clinical data to identify patients with chest pain with normal coronary arteries and no clinical events during follow-up (minimal-risk cohort).

Design, Setting, and Participants

This secondary analysis of a randomized, pragmatic comparative effectiveness trial (Prospective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]) includes stable, symptomatic outpatients without known coronary artery disease referred for noninvasive testing at 193 sites in North America.

Interventions

Patients were randomized to receive coronary computed tomography angiography (CCTA) vs functional testing.

Main Outcomes and Measures

A low-risk tool was developed and internally validated from July 27, 2010, to September 19, 2013, in 4631 patients receiving CCTA as their initial test, with a median follow-up of 25 months. Logistic regression analysis was used to evaluate pretest variables to determine factors associated with minimal risk using a two-thirds random sample for model derivation (n = 3087) and a one-third sample for testing and validation (n = 1544). The model was then applied to the CCTA and functional testing arms, and test results and event rates were ascertained.

Results

A total of 1243 of 4631 patients (26.8%) were in the minimal-risk cohort. The final minimal-risk model included 10 clinical variables that together were correlated with normal CCTA results and no clinical events (C statistic = 0.725 for the derivation and validation subsets; 95% CI, 0.705-0.746): younger age; female sex; racial or ethnic minority; no history of hypertension, diabetes, or dyslipidemia; family history of premature coronary artery disease; never smoking; symptoms unrelated to physical or mental stress; and higher high-density lipoprotein cholesterol level. Across the entire PROMISE cohort, this model was associated with the lowest rates of severely abnormal test results (1.3% for CCTA; 5.6% for functional) and cardiovascular death or myocardial infarction (0.5% for a median of 25 months) among patients at the highest probability (10th decile) of minimal risk.

Conclusions and Relevance

In contemporary practice, more than 25% of patients with stable chest pain referred for noninvasive testing will have normal coronary arteries and no long-term clinical events. A clinical tool using readily available pretest variables discriminates such minimal-risk patients, for whom deferred testing may be considered.

Trial Registration

clinicaltrials.gov Identifier: NCT01174550.

Sex Difference in Patients With Ischemic Heart Failure Undergoing Surgical Revascularization: Results From the STICH Trial (Surgical Treatment for Ischemic Heart Failure)

BACKGROUND

Female sex is conventionally considered a risk factor for coronary artery bypass grafting (CABG) and has been included as a poor prognostic factor in multiple cardiac operative risk evaluation scores. We aimed to investigate the association of sex and the long-term benefit of CABG in patients with ischemic left ventricular dysfunction enrolled in the prospective STICH trial (Surgical Treatment for Ischemic Heart Failure Study).

METHODS

The STICH trial randomized 1212 patients (148 [12%] women and 1064 [88%] men) with coronary artery disease and left ventricular ejection fraction ≤35% to CABG+medical therapy (MED) versus MED alone. Long-term (10-year) outcomes with each treatment were compared according to sex.

RESULTS

At baseline, women were older (63.4 versus 59.3 years; P=0.016) with higher body mass index (27.9 versus 26.7 kg/m²; P=0.001). Women had more coronary artery disease risk factors (diabetes mellitus, 55.4% versus 37.2%; hypertension, 70.9% versus 58.6%; hyperlipidemia, 70.3% versus 58.9%) except for smoking (13.5% versus 21.8%) and had lower rates of prior CABG (0% versus 3.4%; all P<0.05) than men. Moreover, women had higher New York Heart Association class (class III/IV, 66.2% versus 57.0%), lower 6-minute walk capacity (300 versus 350 m), and lower Kansas City Cardiomyopathy Questionnaire overall summary scores (51 versus 63; all P<0.05). Over 10 years of follow-up, all-cause mortality (49.0% versus 65.8%; adjusted hazard ratio, 0.67; 95% confidence interval, 0.52-0.86; P=0.002) and cardiovascular mortality (34.3% versus 52.3%; adjusted hazard ratio, 0.65; 95% confidence interval, 0.48-0.89; P=0.006) were significantly lower in women compared with men. With randomization to CABG+MED versus MED treatment, there was no significant interaction between sex and treatment group in all-cause mortality, cardiovascular mortality, or the composite of all-cause mortality or cardiovascular hospitalization (all P>0.05). In addition, surgical deaths were not statistically different (1.5% versus 5.1%; P=0.187) between sexes among patients randomized to CABG per protocol as initial treatment.

CONCLUSIONS

Sex is not associated with the effect of CABG+MED versus MED on all-cause mortality, cardiovascular mortality, the composite of death or cardiovascular hospitalization, or surgical deaths in patients with ischemic left ventricular dysfunction. Thus, sex should not influence treatment decisions about CABG in these patients.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00023595.

Effect of Catheter Ablation vs Medical Therapy on Quality of Life Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial

Importance

Catheter ablation is more effective than drug therapy in restoring sinus rhythm in patients with atrial fibrillation (AF), but its incremental effect on long-term quality of life (QOL) is uncertain.

Objective

To determine whether catheter ablation is more beneficial than conventional drug therapy for improving QOL in patients with AF.

Design, Setting, and Participants

An open-label randomized clinical trial of catheter ablation vs drug therapy in 2204 symptomatic patients with AF older than 65 years or 65 years or younger with at least 1 risk factor for stroke. Patients were enrolled from November 2009 to April 2016 from 126 centers in 10 countries. Follow-up ended in December 2017.

Interventions

Pulmonary vein isolation, with additional ablation procedures at the discretion of the investigators, for the catheter ablation group (n = 1108) and standard rhythm and/or rate-control drugs selected and managed by investigators for the drug therapy group (n = 1096).

Main Outcomes and Measures

Prespecified co-primary QOL end points at 12 months, including the Atrial Fibrillation Effect on Quality of Life (AFEQT) summary score (range, 0-100; 0 indicates complete disability and 100 indicates no disability; patient-level clinically important difference, ≥5 points) and the Mayo AF-Specific Symptom Inventory (MAFSI) frequency score (range, 0-40; 0 indicates no symptoms and 40 indicates the most severe symptoms; patient-level clinically important difference, ≤-1.6 points) and severity score (range, 0-30; 0 indicates no symptoms and 30 indicates the most severe symptoms; patient-level clinically important difference, ≤-1.3 points).

Results

Among 2204 randomized patients (median age, 68 years; 1385 patients [63%] were men, 946 [43%] had paroxysmal AF, and 1256 [57%] had persistent AF), the median follow-up was 48.5 months, and 1968 (89%) completed the trial. The mean AFEQT summary score was more favorable in the catheter ablation group than the drug therapy group at 12 months (86.4 points vs 80.9 points) (adjusted difference, 5.3 points [95% CI, 3.7-6.9]; P < .001). The mean MAFSI frequency score was more favorable for the catheter ablation group than the drug therapy group at 12 months (6.4 points vs 8.1 points) (adjusted difference, -1.7 points [95% CI, -2.3 to -1.2]; P < .001) and the mean MAFSI severity score was more favorable for the catheter ablation group than the drug therapy group at 12 months (5.0 points vs 6.5 points) (adjusted difference, -1.5 points [95% CI, -2.0 to -1.1]; P < .001).

Conclusions and Relevance

Among patients with symptomatic atrial fibrillation, catheter ablation, compared with medical therapy, led to clinically important and significant improvements in quality of life at 12 months. These findings can help guide decisions regarding management of atrial fibrillation.

Trial Registration

ClinicalTrials.gov Identifier: NCT00911508.

Effect of Catheter Ablation vs Antiarrhythmic Drug Therapy on Mortality, Stroke, Bleeding, and Cardiac Arrest Among Patients With Atrial Fibrillation: The CABANA Randomized Clinical Trial

IMPORTANCE

Catheter ablation is effective in restoring sinus rhythm in atrial fibrillation (AF), but its effects on long-term mortality and stroke risk are uncertain.

OBJECTIVE

To determine whether catheter ablation is more effective than conventional medical therapy for improving outcomes in AF.

DESIGN, SETTING, AND PARTICIPANTS

The Catheter Ablation vs Antiarrhythmic Drug Therapy for Atrial Fibrillation trial is an investigator-initiated, open-label, multicenter, randomized trial involving 126 centers in 10 countries. A total of 2204 symptomatic patients with AF aged 65 years and older or younger than 65 years with 1 or more risk factors for stroke were enrolled from November 2009 to April 2016, with follow-up through December 31, 2017.

INTERVENTIONS

The catheter ablation group (n = 1108) underwent pulmonary vein isolation, with additional ablative procedures at the discretion of site investigators. The drug therapy group (n = 1096) received standard rhythm and/or rate control drugs guided by contemporaneous guidelines.

MAIN OUTCOMES AND MEASURES

The primary end point was a composite of death, disabling stroke, serious bleeding, or cardiac arrest. Among 13 prespecified secondary end points, 3 are included in this report: all-cause mortality; total mortality or cardiovascular hospitalization; and AF recurrence.

RESULTS

Of the 2204 patients randomized (median age, 68 years; 37.2% female; 42.9% had paroxysmal AF and 57.1% had persistent AF), 89.3% completed the trial. Of the patients assigned to catheter ablation, 1006 (90.8%) underwent the procedure. Of the patients assigned to drug therapy, 301 (27.5%) ultimately received catheter ablation. In the intention-to-treat analysis, over a median follow-up of 48.5 months, the primary end point occurred in 8.0% (n = 89) of patients in the ablation group vs 9.2% (n = 101) of patients in the drug therapy group (hazard ratio [HR], 0.86 [95% CI, 0.65-1.15]; P = .30). Among the secondary end points, outcomes in the ablation group vs the drug therapy group, respectively, were 5.2% vs 6.1% for all-cause mortality (HR, 0.85 [95% CI, 0.60-1.21]; P = .38), 51.7% vs 58.1% for death or cardiovascular hospitalization (HR, 0.83 [95% CI, 0.74-0.93]; P = .001), and 49.9% vs 69.5% for AF recurrence (HR, 0.52 [95% CI, 0.45-0.60]; P < .001).

CONCLUSIONS AND RELEVANCE

Among patients with AF, the strategy of catheter ablation, compared with medical therapy, did not significantly reduce the primary composite end point of death, disabling stroke, serious bleeding, or cardiac arrest. However, the estimated treatment effect of catheter ablation was affected by lower-than-expected event rates and treatment crossovers, which should be considered in interpreting the results of the trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00911508.

Effects of obesity on noninvasive test results in patients with suspected cardiac ischemia: Insights from the PROMISE trial

BACKGROUND

Obesity is a risk factor for coronary artery disease (CAD), but adiposity may mimic symptoms of CAD and reduce the accuracy of diagnostic testing.

METHODS

Patients from the PROMISE trial (n = 8889) were classified according to body mass index (BMI). We assessed relationships between BMI, physician's preference of functional test, test positivity, and results of invasive coronary angiography (Cath) using logistic regression models.

RESULTS

Nearly half (48%) of the patients had BMI ≥ 30 kg/m², and 20% had BMI ≥ 35. Providers were more likely to prefer nuclear myocardial perfusion imaging (MPI) over other functional tests as BMI increased. The rate of test positivity with coronary computed tomographic angiography (CTA) was not different (10% vs. 12%) in patients with BMI ≥35 vs. < 35. The same was true for stress echocardiogram and stress electrocardiogram (positivity 8-13%, P > 0.8 for both). In contrast, MPI was significantly more likely to be positive in those with BMI ≥35 vs. <35 (18% vs. 13%; P = 0.001). The likelihood of obstructive CAD at Cath did not differ with BMI ≥35 vs. <35 in patients having CTA (52% vs. 59%, P = 0.22), but among MPI patients, Cath positivity was only 29% with BMI ≥35 vs. 48% with BMI <35 (P = 0.005). Radiation exposure increased with higher BMI in both MPI and CTA groups.

CONCLUSIONS

Increasing levels of obesity adversely affect the diagnostic yield of MPI more than CTA. The degree of obesity should be considered when choosing evaluation strategies for patients with chest pain.

CLINICAL TRIAL REGISTRATION

PROMISE ClinicalTrials.gov number, NCT01174550.

Predictive Model for High-Risk Coronary Artery Disease

BACKGROUND

Patients with high-risk coronary artery disease (CAD) may be difficult to identify.

METHODS

Using the PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) cohort randomized to coronary computed tomographic angiography (n=4589), 2 predictive models were developed for high-risk CAD, defined as left main stenosis (≥50% stenosis) or either (1) ≥50% stenosis [50] or (2) ≥70% stenosis [70] of 3 vessels or 2-vessel CAD involving the proximal left anterior descending artery. Pretest predictors were examined using stepwise logistic regression and assessed for discrimination and calibration.

RESULTS

High-risk CAD was identified in 6.6% [50] and 2.4% [70] of patients. Models developed to predict high-risk CAD discriminated well: [50], bias-corrected C statistic=0.73 (95% CI, 0.71-0.76); [70], bias-corrected C statistic=0.73 (95% CI, 0.68-0.77). Variables predictive of CAD in both models included family history of premature CAD, age, male sex, lower glomerular filtration rate, diabetes mellitus, elevated systolic blood pressure, and angina. Additionally, smoking history was predictive of [50] CAD and sedentary lifestyle of [70] CAD. Both models characterized high-risk CAD better than the Pooled Cohort Equation (area under the curve=0.70 and 0.71 for [50] and [70], respectively) and Diamond-Forrester risk scores (area under the curve=0.68 and 0.71, respectively). Both [50] and [70] CAD was associated with more frequent invasive interventions and adverse events than non-high-risk CAD (all P<0.0001).

CONCLUSIONS

In contemporary practice, 2.4% to 6.6% of stable, symptomatic patients requiring noninvasive testing have high-risk CAD. A simple combination of pretest clinical variables improves prediction of high-risk CAD over traditional risk assessments.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01174550.

Differential Impact of Mitral Valve Repair on Outcome of Coronary Artery Bypass Grafting With or Without Surgical Ventricular Reconstruction in the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

Background

This study examined the impact of mitral valve repair (MVRe) on survival of patients with moderate or severe (≥2+) MR and ischemic cardiomyopathy randomized to coronary artery bypass grafting (CABG) versus CABG+surgical ventricular reconstruction (SVR) in the STICH trial.

Methods

Among patients with moderate or severe MR and ischemic cardiomyopathy undergoing CABG or CABG+SVR, the impact of MVRe on mortality between the two treatment arms was compared.

Results

Among 867 patients with assessment of baseline MR severity, 211 had moderate or severe MR. After excluding 7 patients who underwent mitral valve replacement, 50, 44, 62, and 48 patients underwent CABG, CABG+MVRe, CABG+SVR, and CABG+SVR+MVRe, respectively. Four-year mortality rates were lower following CABG+MVRe than CABG alone (16% vs. 55%; adjusted hazard ratio [HR] 0.30; 95% CI 0.13-0.71). In contrast, the CABG+SVR+MVRe and CABG+SVR groups had similar 4-year mortality of 39% vs. 39% (adjusted HR 0.88; 95% CI 0.46-1.70). MVRe had a more favorable effect on survival in patients undergoing CABG alone compared to CABG+SVR (p=0.013). Baseline MR severity was similar between patients that received CABG+MVRe and those that underwent CABG+SVR+MVRe. A larger proportion of patients demonstrated a reduction in MR between 4 and 24 months after CABG+MVRe compared to CABG+SVR+MVRe (50.0% versus 25.0%, p=0.023).

Conclusion

In patients with moderate or severe MR and ischemic cardiomyopathy undergoing CABG, MVRe appears to have a favorable effect on survival. The addition of SVR to CABG may attenuate the anticipated benefits of MVRe by limiting the long-term reduction of MR with MVRe.

Variability in Ejection Fraction Measured By Echocardiography, Gated Single-Photon Emission Computed Tomography, and Cardiac Magnetic Resonance in Patients With Coronary Artery Disease and Left Ventricular Dysfunction

IMPORTANCE

Clinical decisions are frequently based on measurement of left ventricular ejection fraction (LVEF). Limited information exists regarding inconsistencies in LVEF measurements when determined by various imaging modalities and the potential impact of such variability.

OBJECTIVE

To determine the intermodality variability of LVEF measured by echocardiography, gated single-photon emission computed tomography (SPECT), and cardiovascular magnetic resonance (CMR) in patients with left ventricular dysfunction.

DESIGN, SETTING, AND PARTICIPANTS

International multicenter diagnostic study with LVEF imaging performed at 127 clinical sites in 26 countries from July 24, 2002, to May 5, 2007, and measured by core laboratories. Secondary study of clinical diagnostic measurements of LVEF in the Surgical Treatment for Ischemic Heart Failure (STICH), a randomized trial to identify the optimal treatment strategy for patients with LVEF of 35% or less and coronary artery disease. Data analysis was conducted from March 19, 2016, to May 29, 2018.

MAIN OUTCOMES AND MEASURES

At baseline, most patients had an echocardiogram and subsets of patients underwent SPECT and/or CMR. Left ventricular ejection fraction was measured by a core laboratory for each modality independent of the results of other modalities, and measurements were compared among imaging methods using correlation, Bland-Altman plots, and coverage probability methods. Association of LVEF by each method and death was assessed.

RESULTS

A total of 2032 patients (mean [SD] age, 60.9 [9.6] years; 1759 [86.6%] male) with baseline LVEF data were included. Correlation of LVEF between modalities was r = 0.601 (for biplane echocardiography and SPECT [n = 385]), r = 0.493 (for biplane echocardiography and CMR [n = 204]), and r = 0.660 (for CMR and SPECT [n = 134]). Bland-Altman plots showed only moderate agreement in LVEF measurements from all 3 core laboratories with no substantial overestimation or underestimation of LVEF by any modality. The percentage of observations that fell within a range of 5% ranged from 43% to 54% between different imaging modalities.

CONCLUSIONS AND RELEVANCE

In this international multicenter study of patients with coronary artery disease and reduced LVEF, there was substantial variation between modalities in LVEF determination by core laboratories. This variability should be considered in clinical management and trial design.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier: NCT00023595.

Implantable cardioverter-defibrillators in heart failure patients with reduced ejection fraction and diabetes

AIM

There is limited information on the outcomes after primary prevention implantable cardioverter-defibrillator (ICD) implantation in patients with heart failure (HF) and diabetes. This analysis evaluates the effectiveness of a strategy of ICD plus medical therapy vs. medical therapy alone among patients with HF and diabetes.

METHODS AND RESULTS

A patient-level combined-analysis was conducted from a combined dataset that included four primary prevention ICD trials of patients with HF or severely reduced ejection fractions: Multicenter Automatic Defibrillator Implantation Trial I (MADIT I), MADIT II, Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE), and Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT). In total, 3359 patients were included in the analysis. The primary outcome of interest was all-cause death. Compared with patients without diabetes (n = 2363), patients with diabetes (n = 996) were older and had a higher burden of cardiovascular risk factors. During a median follow-up of 2.6 years, 437 patients without diabetes died (178 with ICD vs. 259 without) and 280 patients with diabetes died (128 with ICD vs. 152 without). ICDs were associated with a reduced risk of all-cause mortality among patients without diabetes [hazard ratio (HR) 0.56, 95% confidence interval (CI) 0.46-0.67] but not among patients with diabetes (HR 0.88, 95% CI 0.7-1.12; interaction P = 0.015).

CONCLUSION

Among patients with HF and diabetes, primary prevention ICD in combination with medical therapy vs. medical therapy alone was not significantly associated with a reduced risk of all-cause death. Further studies are needed to evaluate the effectiveness of ICDs among patients with diabetes.

Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation (CABANA) Trial: Study Rationale and Design

The Catheter Ablation Versus Anti-arrhythmic Drug Therapy for Atrial Fibrillation (CABANA, NCT00911508)(1) trial is testing the hypothesis that the treatment strategy of percutaneous left atrial catheter ablation for the purpose of eliminating atrial fibrillation (AF) is superior to current state-of-the-art pharmacologic therapy. This international 140-center clinical trial was designed to randomize 2200 patients to a strategy of catheter ablation versus state-of-the-art rate or rhythm control drug therapy. Inclusion criteria include: 1) age > 65, or ≤65 with≥ 1 risk factor for stroke, 2) documented AF warranting treatment, and 3) eligibility for both catheter ablation and≥ 2 anti-arrhythmic or≥ 2 rate control drugs. Patients were followed every 3 to 6 months (median 4 years) and underwent repeat trans-telephonic monitoring, Holter monitoring, and CT/MR in a subgroup of patient studies to assess the impact of treatment on AF recurrence and atrial structure.

With 1100 patients in each treatment arm, CABANA is projected to have 90% power for detecting a 30% relative reduction in the primary composite endpoint of total mortality, disabling stroke, serious bleeding, or cardiac arrest. Secondary endpoints include total mortality; mortality or cardiovascular hospitalization; a combination of mortality, stroke, hospitalization for heart failure or acute coronary artery events; cardiovascular death alone; and heart failure death, as well as AF recurrence, quality of life, and cost effectiveness. At a time when AF incidence is rising rapidly, CABANA will provide critical evidence with which to guide therapy and shape health care policy related to AF for years to come.

Impact of Intubation Time on Survival following Coronary Artery Bypass Grafting: Insights from the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

OBJECTIVE

The authors aimed to assess determinants of intubation time and evaluate its impact on 30-day and 1-year postoperative survival in Surgical Treatment for Ischemic Heart Failure (STICH) trial patients.

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS

A multivariable Cox proportional hazards model was used among the 1,446 surgical patients from the STICH trial who survived 36 hours after operation, in order to identify perioperative factors associated with 30-day and 1-year postoperative mortality. A multivariable logistic regression model was used to determine risk factors associated with intubation time.

MEASUREMENTS AND MAIN RESULTS

At 36 hours post-operation, 1,298 (out of 1,446) were extubated and 148 (10.2%) still intubated. Median postoperative intubation time was 11.4 hours. Among patients surviving 36 hours, a multivariable model was developed to predict 30-day (c-index = 0.88) and 1-year (c-index = 0.78) mortality. Intubation time was the strongest independent predictor of 30-day (hazard ratio [HR] 5.50) and 1-year mortality (HR 3.69). Predictors of intubation time >36 hours included mitral valve procedure, New York Heart Association class, left ventricular systolic volume index, creatinine, previous coronary artery bypass grafting (CABG), and age. Results were similar in patients surviving 24 hours post-operation, where intubation time was also the strongest predictor of 30-day (HR 4.18, c-index 0.87) and 1-year (HR 2.81, c-index 0.78) mortality.

CONCLUSIONS

Intubation time is the strongest predictor of 30-day and 1-year mortality among patients with ischemic heart failure undergoing CABG. Combining intubation time with other mortality risk factors may allow the identification of patients at the highest risk for whom the development of specific strategies may improve outcomes.

Effect of high-dose oral multivitamins and minerals in participants not treated with statins in the randomized Trial to Assess Chelation Therapy (TACT)

IMPORTANCE

In a prespecified subgroup analysis of participants not on statin therapy at baseline in the TACT, a high-dose complex oral multivitamins and multimineral regimen was found to have a large unexpected benefit compared with placebo. The regimen tested was substantially different from any vitamin regimen tested in prior clinical trials.

OBJECTIVE

To explore these results, we performed detailed additional analyses of participants not on statins at enrollment in TACT.

DESIGN

TACT was a factorial trial testing chelation treatments and a 28-component high-dose oral multivitamins and multiminerals regimen versus placebo in post-myocardial infarction (MI) patients 50 years or older.

PARTICIPANTS

There were 460 (27%) of 1,708 TACT participants not taking statins at baseline, 224 (49%) were in the active vitamin group and 236 (51%) were in the placebo group.

SETTING

Patients were enrolled at 134 sites around the United States and Canada.

INTERVENTION

Daily high-dose oral multivitamins and multiminerals (6 tablets, active or placebo).

MAIN OUTCOME

The primary end point of TACT was time to the first occurrence of any component of the composite end point: all-cause mortality, MI, stroke, coronary revascularization, or hospitalization for angina.

RESULTS

The primary end point occurred in 137 nonstatin participants (30%), of which 51 (23%) of 224 were in the active group and 86 (36%) of 236 were taking placebo (hazard ratio, 0.62; 95% confidence interval, 0.44-0.87; P=.006). Results in the key TACT secondary end point, a combination of cardiovascular mortality, stroke, or recurrent MI, was consistent in favoring the active vitamin group (hazard ratio, 0.46; 95% confidence interval, 0.28-0.75; P=.002). Multiple end point analyses were consistent with these results.

CONCLUSION AND RELEVANCE

High-dose oral multivitamin and multimineral supplementation seem to decrease combined cardiac events in a stable, post-MI population not taking statin therapy at baseline. These unexpected findings are being retested in the ongoing TACT2.

Daytime versus Night Time Intentional Drug Overdose: The Outcome is Different

Introduction

In drug overdose, it is generally perceived that the dosage can predict the clinical outcome. Are the dosages of intentional drug overdosing the same between day and night? If so, are these overdoses followed by similar clinical outcomes? Answers to these two questions might affect resource allocation and clinical judgment. The present study was performed to establish whether daytime patients and night time patients report similar drug doses, and see which group of patients would have a higher incidence of severe outcomes.

Method

A retrospective observational study on intentional drug overdose was performed. The reported numbers of total tablets ingested and the incidences of major outcomes, in terms of death and intensive care unit admissions, were compared between daytime and night time.

Results

A total of 400 patients were included. The reported number of ingested tablets in daytime had no statistical difference with that at night time. The numbers of severe outcomes had no differences between the patients presenting to the emergency department at daytime or night time. Yet overdosing at night time was more likely associated with severe outcomes.

Conclusions

We advise a higher index of suspicion at the emergency department on the reliability of the dosages reported by patients who overdose during night time. The larger number of severe outcomes may also be related to more toxic drug exposures in the night time. More resources in the community could be allocated to self-harm prevention at night time.

Impact of Diabetes Mellitus on the Evaluation of Stable Chest Pain Patients: Insights From the PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) Trial

Background

The impact of diabetes mellitus on the clinical presentation and noninvasive test (NIT) results among stable outpatients presenting with symptoms suggestive of coronary artery disease (CAD) has not been well described.

Methods and Results

The PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) trial enrolled 10 003 patients with known diabetic status, of whom 8966 were tested as randomized and had interpretable NIT results (1908 with diabetes mellitus, 21%). Differences in symptoms and NIT results were evaluated using logistic regression. Patients with diabetes mellitus (versus without) were similar in age (median 61 versus 60 years) and sex (female 54% versus 52%), had a greater burden of cardiovascular comorbidities, and had a similar likelihood of nonchest pain symptoms (29% versus 27%). The Diamond‐Forrester/Coronary Artery Surgery Study score predicted that patients with diabetes mellitus (versus without) had similar likelihood of obstructive CAD (low 1.8% versus 2.7%; intermediate 92.3% versus 92.6%; high 5.9% versus 4.7%). Physicians estimated patients with diabetes mellitus to have a higher likelihood of obstructive CAD (low to very low: 28.3% versus 40.1%; intermediate 63.9% versus 55.9%; high to very high 7.8% versus 4.0%). Patients with diabetes mellitus (versus without) were more likely to have a positive NIT result (15% versus 11%; adjusted odds ratio, 1.23; P=0.01).

Conclusions

Stable chest pain patients with and without diabetes mellitus have similar presentation and pretest likelihood of obstructive CAD; however, physicians perceive that patients with diabetes mellitus have a higher pretest likelihood of obstructive CAD, an assessment supported by increased risk of a positive NIT. Further evaluation of diabetes mellitus's influence on CAD assessment is required.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01174550.

Quantifying sociodemographic and income disparities in medical therapy and lifestyle among symptomatic patients with suspected coronary artery disease: a cross-sectional study in North America

OBJECTIVES

To evaluate potential gaps in preventive medical therapy and healthy lifestyle practices among symptomatic patients with suspected coronary artery disease (CAD) seeing primary care physicians and cardiologists and how gaps vary by sociodemographic characteristics and baseline cardiovascular risk.

DESIGN

Cross-sectional study assessing potential preventive gaps.

PARTICIPANTS

10 003 symptomatic outpatients evaluated by primary care physicians, cardiologists or other specialists for suspected CAD.

SETTING

PROspective Multicenter Imaging Study for Evaluation of Chest Painfrom 2010 to 2014.

MEASURES

Primary measures were absence of an antihypertensive, statin or angiotensin-converting enzyme inhibitor/angiotensin receptor blocker for renal protection in patients with hypertension, dyslipidaemia or diabetes, respectively, and being sedentary, smoking or being obese.

RESULTS

Preventive treatment gaps affected 14% of patients with hypertension, 36% of patients with dyslipidaemia and 32% of patients with diabetes. Overall, 49% of patients were sedentary, 18% currently smoked and 48% were obese. Women were significantly more likely to not take a statin for dyslipidaemia and to be sedentary. Patients with lower socioeconomic status were also significantly more likely to not take a statin. Compared with Whites, Blacks were significantly more likely to be obese, while Asians were less likely to smoke or be obese. High-risk patients sometimes experienced larger preventive care gaps than low-risk patients. For patients with dyslipidaemia, the presence of a treatment gap was associated with a higher risk of an adverse event (HR 1.35, 95% CI 1.02 to 1.82).

CONCLUSIONS

Among contemporary, symptomatic patients with suspected CAD, significant gaps exist in preventive care and lifestyle practices, and high-risk patients sometimes had larger gaps. Differences by sex, age, race/ethnicity, socioeconomic status and geography are modest but contribute to disparities and have implications for improving opulation health. For patients with dyslipidaemia, the presence of a treatment gap was associated with a higher risk of an adverse event.

CLINICAL TRIAL REGISTRATION

Clinical Trials.gov identifier NCT01174550.

New York Heart Association class and the survival benefit from primary prevention implantable cardioverter defibrillators: A pooled analysis of 4 randomized controlled trials

BACKGROUND

Primary prevention implantable cardioverter defibrillator (ICD) reduce all-cause mortality by reducing sudden cardiac death. There are conflicting data regarding whether patients with more advanced heart failure derive ICD benefit owing to the competing risk of nonsudden death.

METHODS

We performed a patient-level meta-analysis of New York Heart Association (NYHA) class II/III heart failure patients (left ventricular ejection fraction ≤35%) from 4 primary prevention ICD trials (MADIT-I, MADIT-II, DEFINITE, SCD-HeFT). Bayesian-Weibull survival regression models were used to assess the impact of NYHA class on the relationship between ICD use and mortality.

RESULTS

Of the 2,763 patients who met study criteria, 68% (n=1,867) were NYHA II and 52% (n=1,435) were randomized to an ICD. In a multivariable model including all study patients, the ICD reduced mortality (hazard ratio [HR] 0.65, 95% posterior credibility interval [PCI]) 0.40-0.99). The interaction between NYHA class and the ICD on mortality was significant (posterior probability of no interaction=.036). In models including an interaction term for the NYHA class and ICD, the ICD reduced mortality among NYHA class II patients (HR 0.55, PCI 0.35-0.85), and the point estimate suggested reduced mortality in NYHA class III patients (HR 0.76, PCI 0.48-1.24), although this was not statistically significant.

CONCLUSIONS

Primary prevention ICDs reduce mortality in NYHA class II patients and trend toward reducing mortality in the heterogeneous group of NYHA class III patients. Improved risk stratification tools are required to guide patient selection and shared decision making among NYHA class III primary prevention ICD candidates.