Abatacept Pharmacokinetics and Exposure Response in Patients Hospitalized With COVID-19: A Secondary Analysis of the ACTIV-1 IM Randomized Clinical Trial

Importance

The pharmacokinetics of abatacept and the association between abatacept exposure and outcomes in patients with severe COVID-19 are unknown.

Objective

To characterize abatacept pharmacokinetics, relate drug exposure with clinical outcomes, and evaluate the need for dosage adjustments.

Design, Setting, and Participants

This study is a secondary analysis of data from the ACTIV-1 (Accelerating COVID-19 Therapeutic Interventions and Vaccines) Immune Modulator (IM) randomized clinical trial conducted between October 16, 2020, and December 31, 2021. The trial included hospitalized adults who received abatacept in addition to standard of care for treatment of COVID-19 pneumonia. Data analysis was performed between September 2022 and February 2024.

Exposure

Single intravenous infusion of abatacept (10 mg/kg with a maximum dose of 1000 mg).

Main Outcomes and Measures

Mortality at day 28 was the primary outcome of interest, and time to recovery at day 28 was the secondary outcome. Drug exposure was assessed using the projected area under the serum concentration time curve over 28 days (AUC0-28). Logistic regression modeling was used to analyze the association between drug exposure and 28-day mortality, adjusted for age, sex, and disease severity. The association between time to recovery and abatacept exposure was examined using Fine-Gray modeling with death as a competing risk, and was adjusted for age, sex, and disease severity.

Results

Of the 509 patients who received abatacept, 395 patients with 848 serum samples were included in the population pharmacokinetic analysis. Their median age was 55 (range, 19-89) years and most (250 [63.3%]) were men. Abatacept clearance increased with body weight and more severe disease activity at baseline. Drug exposure was higher in patients who survived vs those who died, with a median AUC0-28 of 21 428 (range, 8462-43 378) mg × h/L vs 18 262 (range, 9628-27 507) mg × h/L (P < .001). Controlling for age, sex, and disease severity, an increase of 5000 units in AUC0-28 was associated with lower odds of mortality at day 28 (OR, 0.52 [95% CI, 0.35-0.79]; P = .002). For an AUC0-28 of 19 400 mg × h/L or less, there was a higher probability of recovery at day 28 (hazard ratio, 2.63 [95% CI, 1.70-4.08] for every 5000-unit increase; P < .001). Controlling for age, sex, and disease severity, every 5000-unit increase in AUC0-28 was also associated with lower odds of a composite safety event at 28 days (OR, 0.46 [95% CI, 0.33-0.63]; P < .001). Using the dosing regimen studied in the ACTIV-1 IM trial, 121 of the 395 patients (30.6%) would not achieve an abatacept exposure of at least 19 400 mg × h/L, particularly at the extremes of body weight. Using a modified, higher-dose regimen, only 12 patients (3.0%) would not achieve the hypothesized target abatacept exposure.

Conclusions and Relevance

In this study, patients who were hospitalized with severe COVID-19 and achieved higher projected abatacept exposure had reduced mortality and a higher probability of recovery with fewer safety events. However, abatacept clearance was high in this population, and the current abatacept dosing (10 mg/kg intravenously with a maximum of 1000 mg) may not achieve optimal exposure in all patients.

Trial Registration

ClinicalTrials.gov Identifier: NCT04593940.

Estimated Glomerular Filtration Rate Variability in Patients With Heart Failure and Chronic Kidney Disease

BACKGROUND

Greater variability in the estimated glomerular filtration rate (eGFR) is associated with higher mortality in patients with chronic kidney disease (CKD). Heart failure (HF) is common in CKD and may increase variability through changes in hemodynamic and volume regulation. We sought to determine if patients with vs without HF have higher kidney function variability in CKD, and to define the association with mortality.

METHODS AND RESULTS

Patients undergoing coronary angiography from 2003 to 2013 with an eGFR of less than 60 mL/min/1.73 m² were evaluated from the Duke Databank for Cardiovascular Disease. Variability in the eGFR, measured as the coefficient of variation (CV) of residuals from the regression of eGFR vs time, was calculated spanning 3 months to 2 years after catheterization. Mortality was assessed 2 to 7 years after catheterization. Patients were grouped into 3 HF phenotypes: HF with reduced ejection fraction, HF with preserved ejection, and no HF. Regression was used to evaluate associations between HF phenotypes and variability in the eGFR and between variability in the eGFR and mortality rate with stratification by HF phenotype. Among 3767 participants, the median eGFR at baseline was 45 mL/min/1.73 m² (interquartile range 33-53 mL/min/1.73 m²), and longitudinal measures of eGFR over 21 months had within-patient residual variability (CV) of 14% (9%-20%). In adjusted analyses, variability in the eGFR was greater in those with HF with preserved ejection (n = 695, CV difference 0.98%, 95% confidence interval 0.14%-1.81%) or HF with reduced ejection fraction (n = 800, CV difference 2.51%, 95% confidence interval 1.66%-3.37%) relative to no HF (n = 2272). In 3068 participants eligible for mortality analysis, the presence of HF and greater variability in the eGFR were each associated independently with higher mortality, but there was no evidence of interaction between variability in the eGFR and any HF phenotype (all P for interaction ≥.49).

CONCLUSIONS

Variability in the eGFR is greater in patients with HF and associated with mortality. Prediction algorithms and classification schemes should consider not only static, but also dynamic eGFR variability in HF and CKD prognostication.

The prognostic value of diastolic and systolic mechanical left ventricular dyssynchrony among patients with coronary artery disease and heart failure

BACKGROUND

Prevalence and prognostic value of diastolic and systolic dyssynchrony in patients with coronary artery disease (CAD) + heart failure (HF) or CAD alone are not well understood.

METHODS

We included patients with gated single-photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) between 2003 and 2009. Patients had at least one major epicardial obstruction ≥ 50%. We assessed the association between dyssynchrony and outcomes, including all-cause and cardiovascular death.

RESULTS

Of the 1294 patients, HF was present in 25%. Median follow-up was 6.7 years (IQR 4.9-9.3) years with 537 recorded deaths. Patients with CAD + HF had a higher incidence of dyssynchrony than patients with CAD alone (diastolic BW 28.8% for the HF + CAD vs 14.7% for the CAD alone). Patients with CAD + HF had a lower survival than CAD alone at 10 years (33%; 95% CI 27-40 vs 59; 95% CI 55-62, P < 0.0001). With one exception, HF was found to have no statistically significant interaction with dyssynchrony measures in unadjusted and adjusted survival models.

CONCLUSIONS

Patients with CAD + HF have a high prevalence of mechanical dyssynchrony as measured by GSPECT MPI, and a higher mortality than CAD alone. However, clinical outcomes associated with mechanical dyssynchrony did not differ in patients with and without HF.

Pulmonary Hypertension Subtypes and Mortality in CKD

RATIONALE & OBJECTIVE

Pulmonary hypertension (PH) contributes to cardiovascular disease and mortality in patients with chronic kidney disease (CKD), but the pathophysiology is mostly unknown. This study sought to estimate the prevalence and consequences of PH subtypes in the setting of CKD.

STUDY DESIGN

Observational retrospective cohort study.

SETTING & PARTICIPANTS

We examined 12,618 patients with a right heart catheterization in the Duke Databank for Cardiovascular Disease from January 1, 2000, to December 31, 2014.

EXPOSURES

Baseline kidney function stratified by CKD glomerular filtration rate category and PH subtype.

OUTCOMES

All-cause mortality.

ANALYTICAL APPROACH

Multivariable Cox proportional hazards analysis.

RESULTS

In this cohort, 73.4% of patients with CKD had PH, compared with 56.9% of patients without CKD. Isolated postcapillary PH (39.0%) and combined pre- and postcapillary PH (38.3%) were the most common PH subtypes in CKD. Conversely, precapillary PH was the most common subtype in the non-CKD cohort (35.9%). The relationships between mean pulmonary artery pressure, pulmonary capillary wedge pressure, and right atrial pressure with mortality were similar in both the CKD and non-CKD cohorts. Compared with those without PH, precapillary PH conferred the highest mortality risk among patients without CKD (HR, 2.27; 95% CI, 2.00-2.57). By contrast, in those with CKD, combined pre- and postcapillary PH was associated with the highest risk for mortality in CKD in adjusted analyses (compared with no PH, HRs of 1.89 [95% CI, 1.57-2.28], 1.87 [95% CI, 1.52-2.31], 2.13 [95% CI, 1.52-2.97], and 1.63 [95% CI, 1.12-2.36] for glomerular filtration rate categories G3a, G3b, G4, and G5/G5D).

LIMITATIONS

The cohort referred for right heart catheterization may not be generalizable to the general population. Serum creatinine data in the 6 months preceding catheterization may not reflect true baseline CKD. Observational design precludes assumptions of causality.

CONCLUSIONS

In patients with CKD referred for right heart catheterization, PH is common and associated with poor survival. Combined pre- and postcapillary PH was common and portended the worst survival for patients with CKD.

Echocardiographic Assessment of Right Ventricular Function and Response to Therapy in Pulmonary Arterial Hypertension

Echocardiography is a key tool in the management of patients with pulmonary arterial hypertension (PAH), but many potential parameters could be used to assess response to therapy. In this retrospective study of 48 patients with severe PAH at baseline, we examined echocardiographic variables before and after initiation of PAH-specific therapy to evaluate which measures of right ventricular (RV) function best correlated with clinical response to therapy as assessed by 6-minute walk distance (6MWD) and 3-year all-cause mortality. Tricuspid annular plane systolic excursion (TAPSE), mid-RV and basal-RV diameters, RV systolic pressure, and RV global longitudinal strain were all found to significantly improve after initiation of a PAH therapy. Decreases in right atrial area (r = -0.50, p = 0.002) and mid-RV diameter (r = -0.36, p = 0.03) were most strongly correlated with improvement in 6MWD. Pretreatment values of RA area (hazard ratio [HR] per 1 SD: 2.72; 95% confidence interval [CI] 1.58, 4.69), mid-RV diameter (HR 2.03; 1.20, 3.45), basal-RV diameter (HR 2.27; 1.40, 3.70), and RV global longitudinal strain (HR 2.36; 1.22, 4.56) were all associated with mortality risk. 6MWD and TAPSE were the 2 variables for which pretreatment measures (6MWD - HR 0.35; 0.17, 0.72; TAPSE - HR 0.41; 0.21, 0.82) and change with treatment (6MWD - HR 0.26; 0.10, 0.64; TAPSE - HR 0.40; 0.21, 0.77) were both significantly associated with 3-year mortality. Change in RV systolic pressure with treatment was significantly associated with mortality (HR 2.55; 1.23, 5.28,) but pretreatment baseline had no association (HR 1.48; 0.72, 3.06). Although many echocardiographic parameters change with initiation of PAH treatment, the strong association of both baseline TAPSE and change in TAPSE with mortality supports the ongoing use of TAPSE as an important measure in the assessment of disease severity and treatment response in PAH.

Percutaneous coronary intervention outcomes in patients with stable coronary disease and left ventricular systolic dysfunction

AIMS

We sought to better understand the role of percutaneous coronary intervention (PCI) in patients with stable coronary artery disease (CAD) and moderate or severe left ventricular systolic dysfunction.

METHODS AND RESULTS

Using data from the Duke Databank for Cardiovascular Disease, we analysed patients who underwent coronary angiography at Duke University Medical Center (1995-2012) that had stable CAD amenable to PCI and left ventricular ejection fraction ≤35%. Patients with acute coronary syndrome or Canadian Cardiovascular Society class III or IV angina were excluded. We used propensity-matched Cox proportional hazards to evaluate the association of PCI with mortality and hospitalizations. Of 901 patients, 259 were treated with PCI and 642 with medical therapy. PCI propensity scores created from 24 variables were used to assemble a matched cohort of 444 patients (222 pairs) receiving PCI or medical therapy alone. Over a median follow-up of 7 years, 128 (58%) PCI and 125 (56%) medical therapy alone patients died [hazard ratio 0.87 (95% confidence interval 0.68, 1.10)]; there was also no difference in the rate of a composite endpoint of all-cause mortality or cardiovascular hospitalization [hazard ratio 1.18 (95% confidence interval 0.96, 1.44)] between the two groups.

CONCLUSIONS

In this well-profiled, propensity-matched cohort of patients with stable CAD amenable to PCI and moderate or severe left ventricular systolic dysfunction, the addition of PCI to medical therapy did not improve long-term mortality, or the composite of mortality or cardiovascular hospitalization. The impact of PCI on other outcomes in these high-risk patients requires further study.

Clinical Utility and Prognostic Value of Right Atrial Function in Pulmonary Hypertension

Background Although right atrial (RA) enlargement is an established marker for adverse outcomes, the prognostic importance of RA dysfunction independent of RA size in pulmonary arterial hypertension is not known. Methods and Results Study subjects with pulmonary arterial hypertension were prospectively enrolled from 2010 to 2014. RA function was measured using RA speckle-tracking longitudinal strain and strain rate (SR) during each phase of the cardiac cycle: (1) RA reservoir (peak longitudinal strain, peak systolic SR), (2) RA conduit (peak early diastolic SR), and (3) RA active contraction (peak active contraction strain, peak contraction SR). The primary outcome was a composite of time to hospitalization or death assessed on follow-up. A total of 63 subjects had complete echocardiographic data. Of these, 91% were females, and the mean age was 58±12 years. During the follow-up period (range: 1-58 months), 39 were hospitalized or had died. After multivariable adjustment for age, sex, and left atrial size, peak longitudinal strain, peak active contraction strain, and peak early diastolic SR were significantly associated with increased risk of the composite outcome ( P=0.0005, P=0.0167, and P=0.0054, respectively). Conclusions RA dysfunction independently predicts mortality and hospitalizations in patients with pulmonary arterial hypertension.

Racial differences in long-term outcomes among black and white patients with drug-eluting stents

BACKGROUND

Some studies suggest that black patients may have worse outcomes after drug-eluting stent (DES) placement. There are limited data characterizing long-term outcomes by race. The objective was to compare long-term outcomes between black and white patients after percutaneous coronary intervention (PCI) with DES implantation.

METHODS

We analyzed 915 black and 3,559 white (n = 4,474) consecutive patients who underwent DES placement at Duke University Medical Center from 2005 through 2013. Over 6-year follow up, we compared rates of myocardial infarction (MI), all-cause mortality, revascularization, and major bleeding between black and white patients. A multivariable Cox regression model was fit to adjust for potentially confounding variables. Dual-antiplatelet therapy use over time was determined by patient follow-up surveys and compared by race.

RESULTS

Black patients were younger; were more often female; had higher body mass indexes; had more diabetes mellitus, hypertension, and renal disease; and had lower median household incomes than white patients (P < .001). At 6 years after DES placement, black relative to white patients had higher unadjusted rates of MI (12.1% vs 10.1%, hazard ratio 1.25, 95% CI 1.00-1.57, P = .05) and major bleeding (17.8% vs 14.3%, hazard ratio 1.28, 95% CI 1.07-1.54, P = .01), but there were no significant differences in other outcomes. After multivariable adjustment, there were no statistically significant racial differences in any of these outcomes at 6 years. Similarly, dual-antiplatelet therapy use was comparable between racial groups.

CONCLUSIONS

Unadjusted rates of MI and major bleeding over long-term follow up were higher among black patients compared to white patients, but these differences may be explained by racial differences in comorbid disease.

Trends in cardiorespiratory fitness: The evolution of exercise treadmill testing at a single Academic Medical Center from 1970 to 2012

OBJECTIVE

To identify temporal trends in the use of exercise treadmill testing (ETT) and cardiorespiratory fitness (CRF) estimated by ETT in metabolic equivalents (METs).

PATIENTS AND METHODS

We compiled an ETT database of all available treadmill tests-including those with concomitant stress echocardiography and nuclear perfusion imaging studies-performed at Duke University Hospital from January 1, 1970- December 31, 2012. Six different ramp protocols were used in these combined modalities. CRF at maximal exertion was estimated using established metrics. Eligible patients were required to have no missing data on maximal treadmill speed, grade, and protocol.

RESULTS

The most commonly used ETT protocol was the Bruce (n = 28,877), followed by manual test (n = 7390). Since the 1980's, the use of ETT for clinical purposes declined substantially; there was a decreased trend in utilization of 9.4% over the decades 1990-1999 and 2000-2009. When standard protocol (Bruce) was assessed in isolation, trends in CRF decreased progressively from 1970 to 2012 (mean METs (standard deviation): 11.7 (4.3) to 10.5 (3.5)). After adjusting for baseline comorbidities, the trend was reduced to a lesser degree.

CONCLUSIONS

The use of ETT at our institution has declined over time, perhaps due to changes in clinical practice. In patients undergoing ETT using the standard Bruce protocol, CRF decreased progressively over the last five decades. Future studies are needed to clarify the etiology of the decrease in use of such a powerful predictor of clinical outcomes in our medical care environment.

Long-term outcomes of mitral regurgitation by type and severity

BACKGROUND

We aimed to determine the association of MR severity and type with all-cause death in a large, real-world, clinical setting.

METHODS

We reviewed full echocardiography studies at Duke Echocardiography Laboratory (01/01/1995-12/31/2010), classifying MR based on valve morphology, presence of coronary artery disease, and left ventricular size and function. Survival was compared among patients stratified by MR type and baseline severity.

RESULTS

Of 93,007 qualifying patients, 32,137 (34.6%) had ≥mild MR. A total of 8094 (8.7%) had moderate/severe MR, which was primary myxomatous (14.1%), primary non-myxomatous (6.2%), secondary non-ischemic (17.0%), and secondary ischemic (49.4%). At 10 years, patients with primary myxomatous MR or MR due to indeterminate cause had survival rates of >60%; primary non-myxomatous, secondary ischemic, and non-ischemic MR had survival rates <50%. While mild (HR 1.06, 95% CI 1.03-1.09), moderate (HR 1.31, 95% CI 1.27-1.37), and severe (HR 1.55, 95% CI 1.46-1.65) MR were independently associated with all-cause death, the relationship of increasing MR severity with mortality varied across MR types (P ≤ .001 for interaction); the highest risk associated with worsening severity was seen in primary myxomatous MR followed by secondary ischemic MR and primary non-myxomatous MR.

CONCLUSIONS

Although MR severity is independently associated with increased all-cause death risk for most forms of MR, the absolute mortality rates associated with worse MR severity are much higher for primary myxomatous, non-myxomatous, and secondary ischemic MR. The findings from this study support carefully defining MR by type and severity.

The relationship between baseline and follow-up left ventricular ejection fraction with adverse events among primary prevention ICD patients

BACKGROUND

Left ventricular ejection fraction (LVEF) is used to select patients for primary prevention implantable cardioverter defibrillators (ICDs). The relationship between baseline and long-term follow-up LVEF and clinical outcomes among primary prevention ICD patients remains unclear.

METHODS

We studied 195 patients with a baseline LVEF ≤35% ≤6 months prior to ICD implantation and follow-up LVEF 1-3 years after ICD implantation without intervening left ventricular assist device (LVAD) or transplant. The co-primary study endpoints were: (1) a composite of time to death, LVAD, or transplant and (2) appropriate ICD therapy. We examined multivariable Cox proportional hazard models with a 3-year post-implant landmark view; the LVEF closest to the 3-year mark was considered the follow-up LVEF for analyses. Follow-up LVEF was examined using 2 definitions: (1) ≥10% improvement compared to baseline or (2) actual value of ≥40%.

RESULTS

Fifty patients (26%) had a LVEF improvement of ≥10% and 44 (23%) had a follow-up LVEF ≥40%. Neither baseline nor follow-up LVEF was significantly associated with the composite endpoint. In contrast, both baseline and follow-up LVEF were associated with risk for long-term ICD therapies, whether follow-up LVEF was modeled as a ≥10% absolute improvement (baseline LVEF HR 0.87, CI 0.91-0.93, P < .001; follow-up LVEF HR 0.18, CI 0.06-0.53, P = .002) or a ≥40% follow-up value (baseline LVEF HR 0.89, CI 0.83-0.96, P = .001, follow-up LVEF HR 0.26, CI 0.08-0.87, P = .03).

CONCLUSIONS

Among primary prevention ICD recipients, both baseline and follow-up LVEF were independently associated with long-term risk for appropriate ICD therapy, but they were not associated with time to the composite of LVAD, transplant, or death.

Predicting risk of cardiac events among ST-segment elevation myocardial infarction patients with conservatively managed non-infarct-related artery coronary artery disease: An analysis of the Duke Databank for Cardiovascular Disease

BACKGROUND

Recent randomized evidence has demonstrated benefit with complete revascularization during the index hospitalization for multivessel coronary artery disease ST-segment elevation myocardial infarction (STEMI) patients; however, this benefit likely depends on the risk of future major adverse cardiovascular events (MACE).

METHODS

Using data from Duke University Medical Center (2003-2012), we identified those at high risk for 1-year MACE among 664 STEMI patients with conservatively managed non-infarct-related artery (non-IRA) lesions. Using multivariable logistic regression, we identified clinical and angiographic characteristics associated with MACE (death, myocardial infarction, urgent revascularization) to 1 year and developed an integer-based risk prediction model for clinical use.

RESULTS

In this cohort (median age 60 years, 30% female), the unadjusted Kaplan-Meier rates for MACE at 30 days and 1 year were 10% and 28%, respectively. Characteristics associated with MACE at 1 year included reduced left ventricular ejection fraction, hypertension, heart failure, higher-risk non-IRA vessels (left main), renal insufficiency, and greater % stenosis of non-IRA lesions. A 15-point risk score including these variables had modest discrimination (C-index 0.67) across a spectrum of subsequent risk (4%-88%) for 1-year MACE.

CONCLUSIONS

There is a wide spectrum of risk following primary percutaneous coronary intervention for STEMI patients with multivessel disease. Using readily available clinical characteristics, the expected incidence of MACE by 1 year can be calculated with a simplified risk score, facilitating a tailored approach to clinical care.

Comparative Efficacy of Coronary Revascularization Procedures for Multivessel Coronary Artery Disease in Patients With Chronic Kidney Disease

Patients with chronic kidney disease (CKD) are at increased risk of cardiovascular disease and death, yet little data exist regarding the comparative efficacy of coronary revascularization procedures in CKD patients with multivessel disease. We created a cohort of 4,687 adults who underwent cardiac catheterization, had a serum creatinine value measured within 30 days, and had more than one vessel with ≥50% stenosis. We used Cox proportional hazard regression modeling weighted by the inverse probability of treatment to examine the association between 4 treatment strategies (medical management, percutaneous coronary intervention [PCI] with bare metal stent, PCI with drug-eluting stent, and coronary artery bypass grafting [CABG]) and mortality among patients across categories of estimated glomerular filtration rate; secondary outcome was a composite of mortality, myocardial infarction, or revascularization. Compared with medical management, CABG was associated with a reduced risk of death for patients of any nondialysis CKD severity (hazard ratio [HR] range 0.43 to 0.59). There were no significant mortality differences between CABG and PCI, except a decreased death risk in CABG-treated CKD patients (HR range 0.54 to 0.55). Compared with medical management and PCI, CABG was associated with a lower risk of death, myocardial infarction, or revascularization in nondialysis CKD patients (HR range 0.41 to 0.64). There were similar associations between decreased estimated glomerular filtration rate and increased mortality across all multivessel coronary artery disease patient treatment groups. When accounting for treatment propensity, surgical revascularization was associated with improved outcomes in patients of all CKD severities. A prospective randomized trial in CKD patients is required to confirm our findings.

The prognostic value of mechanical left ventricular dyssynchrony defined by phase analysis from gated single-photon emission computed tomography myocardial perfusion imaging among patients with coronary heart disease

BACKGROUND

The prognostic value of left ventricular dyssynchrony measured by gated single-photon emission computed tomography (GSPECT) myocardial perfusion imaging (MPI) and its relationship to electrical dyssynchrony measured by QRS duration are incompletely understood. The aim of this study was therefore to examine the independent and incremental prognostic value of dyssynchrony in yet the largest group of patients with coronary artery disease (CAD).

METHODS AND RESULTS

Patients presenting for GSPECT- MPI between July 1993 and May 1999 in normal sinus rhythm were identified from the Duke Nuclear Cardiology Databank and the Duke Databank for Cardiovascular Disease (N = 1244). After a median of 4.2 years, 336 deaths occurred. At 8 years, the Kaplan-Meier estimates of the probability of death were 34.0% among patients with a phase bandwidth <100° and 56.8% among those with a bandwidth ≥100°. After adjustment for standard clinical variables, QRS dyssynchrony was independently associated with death (Hazard Ratio (HR), per 10°: 1.092, 95% Confidence Interval (CI) 1.048,1.139, P < .0001). Phase bandwidth was similarly associated with death after clinical adjustment (HR per 10°: 1.056, 95% CI 1.041,1.072, P < .0001). In clinically adjusted models examining QRS duration in addition to phase bandwidth, phase bandwidth had a stronger association with mortality. After accounting for left ventricular ejection fraction (LVEF), neither QRS duration nor phase bandwidth were statistically significant. Among patients with EF >35%, QRS duration and phase bandwidth together provided value above that provided by LVEF alone (P = 0.0181). When examining cardiovascular death, results were consistent with all-cause death.

CONCLUSIONS

Among patients with CAD, mechanical left ventricular dyssynchrony measured by GSPECT MPI has a stronger relationship with outcomes than electrical dyssynchrony measured by QRS duration. After adjustment for baseline characteristics and LVEF, neither mechanical nor electrical dyssynchrony is independently associated with all-cause death or cardiac death. Among patients with EF >35%, mechanical and electrical dyssynchrony together provided prognostic value above that afforded by LVEF.

Race and Sex Differences in QRS Interval and Associated Outcome Among Patients with Left Ventricular Systolic Dysfunction

Background

Prolonged QRS duration is associated with increased mortality among heart failure patients, but race or sex differences in QRS duration and associated effect on outcomes are unknown.

Methods and Results

We investigated QRS duration and morphology among 2463 black and white patients with heart failure and left ventricular ejection fraction ≤35% who underwent coronary angiography and 12‐lead electrocardiography at Duke University Hospital from 1995 through 2011. We used multivariable Cox regression models to assess the relationship between QRS duration and all‐cause mortality and investigate race‐QRS and sex‐QRS duration interaction. Median QRS duration was 105 ms (interquartile range [IQR], 92–132) with variation by race and sex (P<0.001). QRS duration was longest in white men (111 ms; IQR, 98–139) followed by white women (108 ms; IQR, 92–140), black men (100 ms; IQR, 91–120), and black women (94 ms; IQR, 86–118). Left bundle branch block was more common in women than men (24% vs 14%) and in white (21%) versus black individuals (12%). In black patients, there was a 16% increase in risk of mortality for every 10 ms increase in QRS duration up to 112 ms (hazard ratio, 1.16; 95% CI, 1.07, 1.25) that was not present among white patients (interaction, P=0.06).

Conclusions

Black individuals with heart failure had a shorter QRS duration and more often had non‐left bundle branch block morphology than white patients. Women had left bundle branch block more commonly than men. Among black patients, modest QRS prolongation was associated with increased mortality.

Antianginal medications and long-term outcomes after elective catheterization in patients with coronary artery disease

BACKGROUND

Antianginal medications are a class I recommendation by the American College of Cardiology/American Heart Association guidelines for stable ischemic heart disease. We sought to better understand guidance in drug selection and real-life outcomes of antianginal medication use.

HYPOTHESIS

In patients with stable ischemic heart disease, antianginal medications lower mortality.

METHODS

We evaluated 5608 patients with obstructive coronary artery disease (CAD) on elective cardiac catheterization with follow-up through self-administered questionnaires. Patients were classified as being prescribed a particular medication if they received that medication at index catheterization, or within 3 months postcatheterization. The association between antianginal medication use and outcomes was evaluated using Cox proportional hazards models.

RESULTS

Compared with the 11% not prescribed any antianginal medication, patients prescribed antianginal medication were more likely to be older and female; have a history of hypertension, diabetes mellitus, peripheral vascular disease, or 3-vessel CAD; have lower adjusted mortality (hazard ratio [HR]: 0.75, 95% confidence interval [CI]: 0.63-0.89); and experience mortality or myocardial infarction (HR: 0.83, 95% CI: 0.71-0.98). Compared with patients not taking β-blockers (17%), those taking β-blockers had a lower risk of mortality (HR: 0.76, 95% CI: 0.66-0.88). Patients prescribed calcium channel blockers or long-acting nitrates had a higher risk of mortality compared with nonusers (HR: 1.16, 95% CI: 1.04-1.29; HR: 1.20, 95% CI: 1.08-1.34; respectively).

CONCLUSIONS

Antianginal medications are not universally prescribed among obstructive CAD patients; nonuse was associated with higher mortality. For CAD patients with or without prior myocardial infarction, β-blockers were associated with improved long-term survival.

Prognostic value of the cadmium-zinc-telluride camera: A comparison with a conventional (Anger) camera

BACKGROUND

New multipinhole cadmium-zinc-telluride (CZT) cameras allow for faster imaging and lower radiation doses for single photon emission computed tomography (SPECT) studies, but assessment of prognostic ability is necessary.

METHODS AND RESULTS

We collected data from all myocardial SPECT perfusion studies performed over 15 months at our institution, using either a CZT or conventional Anger camera. A Cox proportional hazards model was used to assess the relationship between camera type, imaging results, and either death or myocardial infarction (MI). Clinical variables including age, sex, body mass index (BMI), and historical risk factors were used for population description and model adjustments. We had 2,088 patients with a total of 69 deaths and 65 MIs (122 events altogether). A 3% increase in DDB (difference defect burden) represented a 12% increase in the risk of death or MI, whereas a 3% increase in rest defect burden or stress defect burden represented an 8% increase; these risks were the same for both cameras (P > .24, interaction tests).

CONCLUSIONS

The CZT camera has similar prognostic values for death and MI to conventional Anger cameras. This suggests that it may successfully be used to decrease patient dose.

Aortic valve surgery and survival in patients with moderate or severe aortic stenosis and left ventricular dysfunction

AIMS

We aimed to determine the frequency of aortic valve surgery (AVR) with or without coronary artery bypass grafting (CABG), among patients with moderate/severe aortic stenosis (AS) and left ventricular systolic dysfunction (LVSD), and its relationship with survival.

METHODS AND RESULTS

The Duke Echocardiographic Database (N = 132 804) was queried for patients with mean gradient ≥25 mmHg and/or peak velocity ≥3 m/s and LVSD (left ventricular ejection fraction ≤50%) from 1 January 1995-28 February 2014. For analyses purposes, AS was defined both by mean gradient and calculated aortic valve area (AVA) criteria. Time-dependent indicators of AVR in multivariable Cox models were used to assess the relationship of AVR and all-cause mortality. A total of 1634 patients had moderate (N = 1090, 67%) or severe (N = 544, 33%) AS by mean gradient criteria. Overall, 287 (26%) patients with moderate AS and 263 (48%) patients with severe AS underwent AVR within 5 years of the qualifying echo. There were 863 (53%) deaths observed up to 5 years following index echo. After multivariable adjustment in an inverse probability weighted regression model, AVR was associated with higher 5-year survival amongst patients with moderate AS and severe AS whether classified by AVA or mean gradient criteria. Over all, AVR ± CABG compared with medical therapy was associated with significantly lower mortality [hazard ratio, HR = 0.49 (0.38, 0.62), P < 0.0001]. Compared with CABG alone, CABG + AVR was associated with better survival [HR = 0.18 (0.12, 0.27), P < 0.0001].

CONCLUSIONS

In patients with moderate/severe AS and LVSD, mortality is substantial and amongst those selected for surgery, AVR with or without CABG is associated with higher survival. Research is required to understand factors contributing to current practice patterns and the possible utility of transcatheter approaches in this high-risk cohort.

Ischaemia change with revascularisation versus medical therapy in reduced ejection fraction

Objective

Nuclear imaging data demonstrate that revascularisation leads to favourable effects on ischaemia burden and improved outcomes compared with medical therapy (MT). In patients with heart failure (HF), the effects of MT versus revascularisation on ischaemia change and its independent prognostic significance requires investigation.

Methods

From the Duke Databank, we performed a retrospective analysis of 278 consecutive patients with coronary artery disease (CAD) and ejection fraction (EF) ≤40%, who underwent 2 serial myocardial perfusion scans between 1993 and 2009. Ischaemia change was calculated for patients undergoing MT alone, or revascularisation. Cox proportional hazards regression modelling was used to identify factors associated with death/myocardial infarction (MI).

Results

The magnitude of ischeamia reduction was greater with revascularisation than with MT alone (median change of −6% vs 0%, p<0.001). With revascularisation, more patients experienced ≥5% ischaemia reduction compared with MT (52% vs 25%, p<0.01) and a similar percentage experienced ≥5% ischaemia worsening (13% vs 18%, p=0.37). After risk adjustment, ≥5% ischaemia worsening was associated with decreased death/MI (HR=0.58; 95% CI 0.36 to 0.96).

Conclusions

In patients with HF with CAD, revascularisation improves long-term ischaemia burden compared with MT. Ischaemia worsening on nuclear imaging was associated with reduced risk of death/MI, potentially related to development of ischaemic viable myocardium as opposed to scar tissue.

Comparison of the prognostic value of regadenoson and adenosine myocardial perfusion imaging

BACKGROUND

Regadenoson is now widely used in single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI). However, the prognostic value of abnormal stress perfusion findings with regadenoson vs adenosine are unclear. The aim of this study was to evaluate the prognostic value of regadenoson SPECT and to compare it to that of adenosine SPECT.

METHODS AND RESULTS

3698 consecutive patients undergoing either adenosine or regadenoson SPECT were assessed at 1 year for the endpoints of cardiovascular death and a composite endpoint of cardiovascular death or MI. Weighted Cox proportional hazards regression modeling with the inverse probability weighted (IPW) estimators method adjusting to propensity for agent was used to account for differences in baseline characteristics. Patients undergoing adenosine SPECT MPI had a significantly higher prevalence of smoking history, diabetes, hypertension, and prior myocardial infarction (P < .05, all). At 1 year of follow-up, there were 154 cardiovascular deaths and 204 with the composite endpoint of cardiovascular death or MI. Using IPW adjustment to propensity for agent in a model with stress agent, summed stress score (SSS) remained a significant predictor of the composite endpoint of cardiovascular death or MI (HR 1.36 CI 1.28-1.46; P < .0001) as well as cardiovascular death (HR 1.38 CI 1.28-1.49; P < .0001). The interaction of SSS with agent was not significant. Similar findings were seen with summed difference score (SDS).

CONCLUSIONS

SSS derived from either adenosine or regadenoson SPECT MPI is a significant predictor of events and provides incremental prognostic information beyond basic clinical variables. We have shown for the first time that use of regadenoson vs adenosine as stress agent does not modify the prognostic significance of SSS. Similar findings were seen with SDS.

Predictors of long-term clinical endpoints in patients with refractory angina

Background

Clinical outcomes in patients with refractory angina (RA) are poorly characterized and variably described. Using the Duke Database for Cardiovascular Disease (DDCD), we explored characteristics that drive clinical endpoints in patients with class II to IV angina stabilized on medical therapy.

Methods and Results

We explored clinical endpoints and associated costs of patients who underwent catheterization at Duke University Medical Center from 1997 to 2010 for evaluation of coronary artery disease (CAD) and were found to have advanced CAD ineligible for additional revascularization, and were clinically stable for a minimum of 60 days. Of 77 257 cardiac catheterizations performed, 1908 patients met entry criteria. The 3‐year incidence of death; cardiac rehospitalization; and a composite of death, myocardial infarction, stroke, cardiac rehospitalization, and revascularization were 13.0%, 43.5%, and 52.2%, respectively. Predictors of mortality included age, ejection fraction (EF), low body mass index, multivessel CAD, low heart rate, diabetes, diastolic blood pressure, history of coronary artery bypass graft surgery, cigarette smoking, history of congestive heart failure (CHF), and race. Multivessel CAD, EF<45%, and history of CHF increased risk of mortality; angina class and prior revascularization did not. Total rehospitalization costs over a 3‐year period per patient were $10 185 (95% CI 8458, 11912) in 2012 US dollars.

Conclusions

Clinically stable patients with RA who are medically managed have a modest mortality, but a high incidence of hospitalization and resource use over 3 years. These findings point to the need for novel therapies aimed at symptom mitigation in this population and their potential impact on health care utilization and costs.

Extent, location, and clinical significance of non-infarct-related coronary artery disease among patients with ST-elevation myocardial infarction

IMPORTANCE

Little information exists about the anatomical characteristics and clinical relevance of non-infarct-related artery (IRA) disease among patients with ST-segment elevation myocardial infarction (STEMI).

OBJECTIVES

To investigate the incidence, extent, and location of obstructive non-IRA disease and compare 30-day mortality according to the presence of non-IRA disease in patients with STEMI.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective study of patients pooled from a convenience sample of 8 independent, international, randomized STEMI clinical trials published between 1993 and 2007. Follow-up varied from 1 month to 1 year. Among 68,765 patients enrolled in the trials, 28,282 patients with valid angiographic information were included in this analysis. Obstructive coronary artery disease was defined as stenosis of 50% or more of the diameter of a major epicardial artery. To assess the generalizability of trial-based results, external validation was performed using observational data for patients with STEMI from the Korea Acute Myocardial Infarction Registry (KAMIR) (between November 1, 2005, and December 31, 2013; n = 18,217) and the Duke Cardiovascular Databank (between January 1, 2005, and December 31, 2012; n = 1812).

MAIN OUTCOMES AND MEASURES

Thirty-day mortality following STEMI.

RESULTS

Overall, 52.8% (14,929 patients) had obstructive non-IRA disease; 29.6% involved 1 vessel and 18.8% involved 2 vessels. There was no substantial difference in the extent and distribution of non-IRA disease according to the IRA territory. Unadjusted and adjusted rates of 30-day mortality were significantly higher in patients with non-IRA disease than in those without non-IRA disease (unadjusted, 4.3% vs 1.7%, respectively; risk difference, 2.7% [95% CI, 2.3% to 3.0%], P < .001; and adjusted, 3.3% vs 1.9%, respectively; risk difference, 1.4% [95% CI, 1.0% to 1.8%], P < .001). The overall prevalence and association of non-IRA disease with 30-day mortality was consistent with findings from the KAMIR registry (adjusted, 3.6% for patients with non-IRA disease vs 2.5% in those without it; risk difference, 1.1% [95% CI, 0.6% to 1.7%]; P < .001), but not with the Duke database (adjusted, 4.7% with non-IRA disease vs 4.3% without it; risk difference, 0.4% [95% CI, -1.4% to 2.2%], P = .65).

CONCLUSIONS AND RELEVANCE

In a retrospective pooled analysis of 8 clinical trials, obstructive non-IRA disease was common among patients presenting with STEMI, and was associated with a modest statistically significant increase in 30-day mortality. These findings require confirmation in prospectively designed studies, but raise questions about the appropriateness and timing of non-IRA revascularization in patients with STEMI.

Comparison of safety of sotalol versus amiodarone in patients with atrial fibrillation and coronary artery disease

Sotalol is a commonly prescribed antiarrhythmic drug (AAD) used for maintaining sinus rhythm in patients with atrial fibrillation (AF). Although randomized studies have found that sotalol can significantly delay time to AF recurrence, its association with mortality is less clear, particularly among those with coronary artery disease. We examined outcomes of 2,838 patients with coronary artery disease and AF. Using Cox proportional hazards modeling, landmark analysis, and time-dependent covariates for drug therapy, we compared cumulative survival among patients treated with sotalol (n = 226), amiodarone (n = 856), or no AAD (n = 1,756). Median follow-up was 4.2 years (interquartile range [IQR] 2.0-7.4). The median age was 68 years (IQR 60-75). Compared with those treated with amiodarone or no AAD, patients treated with sotalol were less likely to be black (6% vs 13% vs 13%) and have a previous myocardial infarction (35% vs 51% vs 48%) or a left ventricular ejection fraction <40% (13% vs 26% vs 21%). In follow-up, persistence of sotalol was limited; 97% of patients treated with sotalol were treated for <25% of the follow-up period. In adjusted analysis accounting for time on therapy, sotalol use was associated with an increased risk of all-cause death compared with no drug (hazard ratio 1.53, 95% confidence interval 1.19 to 1.96, p = 0.0009), but a decreased risk of death compared with amiodarone (hazard ratio 0.72, 95% confidence interval 0.55 to 0.91, p = 0.0141). In conclusion, sotalol therapy was more frequently used in patients with fewer co-morbidities, often discontinued early in follow-up, and was associated with increased mortality compared with no AAD but decreased mortality relative to amiodarone.

Clinical outcome as a function of the PR-interval-there is virtue in moderation: data from the Duke Databank for cardiovascular disease

AIMS

Recently, a U-shaped association between PR-interval and the risk of developing atrial fibrillation was described, with higher risk in patients with long and short PR-intervals. Little is known regarding the association of PR-interval duration and mortality. The objective of the current study was to explore the relationship between PR-interval and major cardiovascular outcomes in patients with known coronary heart disease.

METHODS AND RESULTS

Patients in sinus rhythm, undergoing coronary angiography at Duke University Medical Center between 1989 and 2010, who had significant stenosis in at least one native coronary artery, were included. Patients with arrhythmia, second- or third-degree AV-block, QRS > 120 ms were excluded. A total of 9,637 patients were included (median age 63, IQR 55-71 years, 67% men). After adjustment for relevant covariates, the risk of a CV event increased with a decreasing PR-interval (10 ms decrements) for PR-interval values <162 ms (all-cause mortality; HR 1.057, 95% CI 1.019-1.096, P = 0.0030, composite of death or stroke; HR 1.047, 95% CI 1.011-1.085, P = 0.0095 and composite of cardiovascular death or cardiovascular rehospitalization; HR 1.032, 95% CI 1.002-1.063, P = 0.0387). No statistically significant changes in the risk associated with PR-interval for values >162 ms were seen for any of the studied endpoints.

CONCLUSION

In patients with coronary heart disease, a prolongation of the PR-interval was not independently associated with poor outcomes, but a PR-interval shorter than normal was associated with increased all-cause mortality and other major cardiovascular events.

Persistent angina pectoris in ischaemic cardiomyopathy: increased rehospitalization and major adverse cardiac events

AIMS

The impact of refractory angina pectoris (AP) in patients with ischaemic cardiomyopathy (ICM) is unknown. We investigated the characteristics and outcomes of ICM patients with persistent AP following cardiac catheterization.

METHODS AND RESULTS

Patients who underwent coronary angiography at Duke from 2000 to 2009 with an EF <40% and ICM with persistent AP were compared with similar patients without persistent AP. Persistent AP was defined by patient report of ischaemic symptoms within 1 year of index catheterization. Time-to-event was examined using Kaplan-Meier or cumulative incidence and Cox proportional hazards modelling methods for death/myocardial infarction (MI)/revascularization [i.e. major adverse cardiac events (MACE)], death/MI, death, and cardiovascular death/hospitalization. Of 965 ICM patients, 298 (31%) had persistent AP. These patients were younger and had more previous revascularization than patients without persistent AP. Both groups had high use of aspirin, beta-blockers, ACE inhibitors, and statins, but modest nitrate use. Over a median follow-up of >5 years, patients with persistent AP had increased rates of MACE, and cardiovascular death/hospitalization compared with patients without persistent AP [5-year cumulative event rates of 53% vs. 46% (P = 0.013) and 73% vs. 60% (P < 0.0001), respectively], but similar rates of death (P = 0.59) and death/MI (P = 0.50). After multivariable adjustment, persistent AP remained associated with increased MACE [hazard ratio (HR) 1.30; 95% confidence interval (CI) 1.08-1.57], and cardiovascular death/hospitalization (HR 1.36; 95% CI 1.14-1.62).

CONCLUSION

Persistent AP is common despite medical therapy in patients with ICM and is independently associated with increased long-term MACE and rehospitalization. Future prospective studies of persistent AP in ICM patients are warranted.

Use of antiarrhythmic drug therapy and clinical outcomes in older patients with concomitant atrial fibrillation and coronary artery disease

AIMS

Atrial fibrillation (AF) and coronary artery disease (CAD) are common in older patients. We aimed to describe the use of antiarrhythmic drug (AAD) therapy and clinical outcomes in these patients.

METHODS AND RESULTS

We analysed AAD therapy and outcomes in 1738 older patients (age ≥65) with AF and CAD in the Duke Databank for cardiovascular disease. The primary outcomes were mortality and rehospitalization at 1 and 5 years. Overall, 35% of patients received an AAD at baseline, 43% were female and 85% were white. Prior myocardial infarction (MI, 31%) and heart failure (41%) were common. Amiodarone was the most common AAD (21%), followed by pure Class III agents (sotalol 6.3%, dofetilide 2.2%). Persistence of AAD was low (35% at 1 year). After adjustment, baseline AAD use was not associated with 1-year mortality [adjusted hazard ratio (HR) 1.23, 95% confidence interval (CI) 0.94-1.60] or cardiovascular mortality (adjusted HR 1.27, 95% CI 0.90-1.80). However, AAD use was associated with increased all-cause rehospitalization (adjusted HR 1.20, 95% CI 1.03-1.39) and cardiovascular rehospitalization (adjusted HR 1.20, 95% CI 1.01-1.43) at 1 year. This association did not persist at 5 years; however, these patients were at very high risk of death (55% for those >75 and on AAD) and all-cause rehospitalization (87% for those >75 and on AAD) at 5 years.

CONCLUSIONS

In older patients with AF and CAD, antiarrhythmic therapy was associated with increased rehospitalization at 1 year. Overall, these patients are at high risk of longer-term hospitalization and death. Safer, better-tolerated, and more effective therapies for symptom control in this high-risk population are warranted.

Surgical revascularization is associated with maximal survival in patients with ischemic mitral regurgitation: a 20-year experience

BACKGROUND

The optimal treatment for ischemic mitral regurgitation remains actively debated. Our objective was to evaluate the relationship between ischemic mitral regurgitation treatment strategy and survival.

METHODS AND RESULTS

We retrospectively reviewed patients at our institution diagnosed with significant coronary artery disease and moderate or severe ischemic mitral regurgitation from 1990 to 2009, categorized by medical treatment alone, percutaneous coronary intervention, coronary artery bypass grafting (CABG), or CABG plus mitral valve repair or replacement. Kaplan-Meier methods and multivariable Cox proportional hazards analyses were performed to assess the relationship between treatment strategy and survival, with the use of propensity scores to account for nonrandom treatment assignment. A total of 4989 patients were included: medical treatment alone=36%, percutaneous coronary intervention=26%, CABG=33%, and CABG plus mitral valve repair or replacement=5%. Median follow-up was 5.37 years. Compared with medical treatment alone, significantly lower mortality was observed in patients treated with percutaneous coronary intervention (adjusted hazard ratio, 0.83; 95% confidence interval, 0.76-0.92; P=0.0002), CABG (adjusted hazard ratio, 0.56; 95% confidence interval, 0.51-0.62; P<0.0001), and CABG plus mitral valve repair or replacement (adjusted hazard ratio, 0.69; 95% confidence interval, 0.57-0.82; P<0.0001). There was no significant difference in these results based on mitral regurgitation severity.

CONCLUSIONS

Patients with significant coronary artery disease and moderate or severe ischemic mitral regurgitation undergoing CABG alone demonstrated the lowest risk of death. CABG with or without mitral valve surgery was associated with lower mortality than either percutaneous coronary intervention or medical treatment alone.

Heart failure with preserved ejection fraction: comparison of patients with and without angina pectoris (from the Duke Databank for Cardiovascular Disease)

OBJECTIVES

This study investigated the characteristics and outcomes of patients with heart failure with preserved ejection fraction (HFpEF) and angina pectoris (AP).

BACKGROUND

AP is a predictor of adverse events in patients with heart failure with reduced EF. The implications of AP in HFpEF are unknown.

METHODS

We analyzed HFpEF patients (EF ≥50%) who underwent coronary angiography at Duke University Medical Center from 2000 through 2010 with and without AP in the previous 6 weeks. Time to first event was examined using Kaplan-Meier methods for the primary endpoint of death/myocardial infarction (MI)/revascularization/stroke (i.e., major adverse cardiac events [MACE]) and secondary endpoints of death/MI/revascularization, death/MI/stroke, death/MI, death, and cardiovascular death/cardiovascular hospitalization.

RESULTS

In the Duke Databank, 3,517 patients met criteria for inclusion and 1,402 (40%) had AP. Those with AP were older with more comorbidities and prior revascularization compared with non-AP patients. AP patients more often received beta-blockers, angiotensin-converting enzyme inhibitors, nitrates, and statins (all p < 0.05). In unadjusted analysis, AP patients had increased MACE and death/MI/revascularization (both p < 0.001), lower rates of death and death/MI (both p < 0.05), and similar rates of death/MI/stroke and cardiovascular death/cardiovascular hospitalization (both p > 0.1). After multivariable adjustment, those with AP remained at increased risk for MACE (hazard ratio [HR]: 1.30, 95% confidence interval [CI]: 1.17 to 1.45) and death/MI/revascularization (HR: 1.29, 95% CI: 1.15 to 1.43), but they were at similar risk for other endpoints (p > 0.06).

CONCLUSIONS

AP in HFpEF patients with a history of coronary artery disease is common despite medical therapy and is independently associated with increased MACE due to revascularization with similar risk of death, MI, and hospitalization.

Soluble ST2 in ambulatory patients with heart failure: Association with functional capacity and long-term outcomes

BACKGROUND

ST2 is involved in cardioprotective signaling in the myocardium and has been identified as a potentially promising biomarker in heart failure (HF). We evaluated ST2 levels and their association with functional capacity and long-term clinical outcomes in a cohort of ambulatory patients with HF enrolled in the Heart Failure: A Controlled Trial Investigating Outcomes of Exercise Training (HF-ACTION) study-a multicenter, randomized study of exercise training in HF.

METHODS AND RESULTS

HF-ACTION randomized 2331 patients with left ventricular ejection fraction <0.35 and New York Heart Association class II to IV HF to either exercise training or usual care. ST2 was analyzed in a subset of 910 patients with evaluable plasma samples. Correlations and Cox models were used to assess the relationship among ST2, functional capacity, and long-term outcomes. The median baseline ST2 level was 23.7 ng/mL (interquartile range, 18.6-31.8). ST2 was modestly associated with measures of functional capacity. In univariable analysis, ST2 was significantly associated with death or hospitalization (hazard ratio, 1.48; P<0.0001), cardiovascular death or HF hospitalization (hazard ratio, 2.14; P<0.0001), and all-cause mortality (hazard ratio, 2.33; P<0.0001; all hazard ratios for log2 ng/mL). In multivariable models, ST2 remained independently associated with outcomes after adjustment for clinical variables and amino-terminal pro-B-type natriuretic peptide. However, ST2 did not add significantly to reclassification of risk as assessed by changes in the C statistic, net reclassification improvement, and integrated discrimination improvement.

CONCLUSIONS

ST2 was modestly associated with functional capacity and was significantly associated with outcomes in a well-treated cohort of ambulatory patients with HF although it did not significantly affect reclassification of risk.

CLINICAL TRIAL INFORMATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00047437.

Association of systemic lupus erythematosus with angiographically defined coronary artery disease: a retrospective cohort study

OBJECTIVE

To determine if systemic lupus erythematosus (SLE) is associated with a higher prevalence of coronary artery disease (CAD) in select patients undergoing coronary angiography. We compared the extent of angiographic abnormalities, CAD risk factors, and all-cause mortality in SLE patients with non-SLE controls.

METHODS

We identified SLE patients (n = 86) and controls matched by sex and year of cardiac catheterization (n = 258) undergoing cardiac catheterization for the evaluation of CAD (median followup duration of 4.3 years). Multivariable logistic regression was used to determine if SLE was associated with obstructive CAD, defined as ≥70% stenosis in a major epicardial coronary artery. Risk-adjusted survival differences between the 2 groups were assessed using Cox proportional hazards modeling.

RESULTS

The SLE patients (85% women) were younger than the non-SLE patients (median age 49 years versus 70 years; P < 0.001) and were less likely to have diabetes mellitus and hyperlipidemia, but had similar rates of hypertension (70% versus 71%; P = 0.892). In unadjusted analyses, SLE and non-SLE patients had similar rates of obstructive CAD by angiography (52% versus 62%; overall P = 0.11). After adjustment for known CAD risk factors, SLE was associated with a significantly increased likelihood of CAD (odds ratio 2.24 [95% confidence interval (95% CI) 1.08-4.67]). SLE was also associated with a nonsignificant increase in all-cause mortality (hazard ratio 1.683 [95% CI 0.98-2.89], P = 0.060).

CONCLUSION

In this selected population, SLE was significantly associated with the presence of CAD as defined by coronary angiography, the gold standard for assessing flow-limiting lesions in this disease. The patients with SLE showed a similar severity of CAD as the controls despite having less than half the rate of diabetes mellitus and being 20 years younger.

Ischemia change in stable coronary artery disease is an independent predictor of death and myocardial infarction

OBJECTIVES

The aim of this study was to evaluate the independent prognostic significance of ischemia change in stable coronary artery disease (CAD).

BACKGROUND

Recent randomized trials in stable CAD have suggested that revascularization does not improve outcomes compared with optimal medical therapy (MT). In contrast, the nuclear substudy of the COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial found that revascularization led to greater ischemia reduction and suggested that this may be associated with improved unadjusted outcomes. Thus, the effects of MT versus revascularization on ischemia change and its independent prognostic significance requires further investigation.

METHODS

From the Duke Cardiovascular Disease and Nuclear Cardiology Databanks, 1,425 consecutive patients with angiographically documented CAD who underwent 2 serial myocardial perfusion single-photon emission computed tomography scans were identified. Ischemia change was calculated for patients undergoing MT alone, percutaneous coronary intervention, or coronary artery bypass grafting. Patients were followed for a median of 5.8 years after the second myocardial perfusion scan. Cox proportional hazards regression modeling was used to identify factors independently associated with the primary outcome of death or myocardial infarction (MI). Formal risk reclassification analyses were conducted to assess whether the addition of ischemia change to traditional predictors resulted in improved risk classification for death or MI.

RESULTS

More MT patients (15.6%) developed ≥5% ischemia worsening compared with those undergoing percutaneous coronary intervention (6.2%) or coronary artery bypass grafting (6.7%) (p < 0.001). After adjustment for established predictors, ≥5% ischemia worsening remained a significant independent predictor of death or MI (hazard ratio: 1.634; p = 0.0019) irrespective of treatment arm. Inclusion of ≥5% ischemia worsening in this model resulted in significant improvement in risk classification (net reclassification improvement: 4.6%, p = 0.0056) and model discrimination (integrated discrimination improvement: 0.0062, p = 0.0057).

CONCLUSIONS

In stable CAD, ischemia worsening is an independent predictor of death or MI, resulting in significantly improved risk reclassification when added to previously known predictors.

Reduction in body weight but worsening renal function with late ultrafiltration for treatment of acute decompensated heart failure

OBJECTIVES

The safety, effectiveness and indications for ultrafiltration (UF) are not well established. We hypothesized that UF would not worsen renal function in patients with heart failure (HF) who were not responding to medical therapy.

METHODS

Data was collected for patients who underwent UF between 2006 and 2010 (n = 72, median age 61 years, 54% males, 61% Caucasian, 54% left ventricular ejection fraction ≥ 40%).

RESULTS

Baseline GFR was 38 ml/min/1.73 m2. All patients were initially treated with loop diuretics and 58% required a thiazide-like diuretic or vasoactive agent. UF resulted in total fluid removal of 11.3 liters and weight loss was 9.7 kg. The median decrease in eGFR during UF was 4.5 ml/min/m2 (IQR--13, 0; p < 0.01) and 43% of patients experienced a ≥ 20% decrease in eGFR. Ten percent of patients required dialysis and 13% died, received a ventricular assist device/cardiac transplant or were discharged to hospice.

CONCLUSIONS

In a cohort of HF patients who did not respond to medical therapy, UF was associated not only with a significant reduction of body weight and fluid removal, but also acute worsening of renal function. Further research to identify the appropriate population for UF, long-term outcomes and the intensity of treatment is required if UF is to gain wide acceptance for HF management.

Antithrombotic therapy for atrial fibrillation and coronary artery disease in older patients

BACKGROUND

Older patients with atrial fibrillation (AF) and coronary artery disease (CAD) face high risk of stroke and bleeding with antithrombotic therapy. Balancing safe and effective use of aspirin, clopidogrel, and warfarin in this population is important.

METHODS

From the Duke Databank for Cardiovascular Disease, we identified patients with AF ≥65 years old with angiographically confirmed CAD from 2000 to 2010. Antithrombotic use was described across age and Congestive heart failure, Hypertension, Age >75 years, Diabetes, prior Stroke/transient ischemic attack (CHADS(2)) stroke risk and Anticoagulation and Risk Factors in Atrial Fibrillation (ATRIA) bleeding scores. Death and the composite of death, myocardial infarction, and stroke by antithrombotic strategy were reported.

RESULTS

Of 2,122 patients ≥65 years old with AF and CAD, 477 (22.5%) were ≥80 years old; 1,133 (53.4%) had acute coronary syndromes. Overall rates of aspirin, clopidogrel, and warfarin use were 83.4%, 34.6%, and 38.9%, respectively. Compared with patients 65 to 79 years old, more patients ≥80 years old were at high stroke risk (CHADS(2) ≥2, 84.7% vs 57.8%) and high bleeding risk (ATRIA 5-10, 55.8% vs 23.3%). Warfarin use in both age groups increased with higher CHADS(2) scores and decreased with higher ATRIA scores. Of patients ≥80 years old with CHADS(2) ≥2, 150 (38.2%) received warfarin. Antithrombotic strategy was not associated with improved 1-year adjusted outcomes.

CONCLUSIONS

Among older patients with AF and CAD, overall warfarin use was low. Patients ≥80 years old at highest stroke risk received warfarin in similar proportions to the overall cohort. Further investigation into optimizing antithrombotic strategies in this population is warranted.

Race and gender variation in the QT interval and its association with mortality in patients with coronary artery disease: results from the Duke Databank for Cardiovascular Disease (DDCD)

BACKGROUND

In several studies, prolongation of the corrected QT (QTc) interval has been associated with an increased risk of cardiac events. However, data on race and gender variation in the QTc and its associated risk of death are lacking.

METHODS

We prospectively followed 19,252 subjects who underwent cardiac catheterization and had at least 1 native coronary artery stenosis ≥75%. Automated QTc measurements were obtained from a baseline electrocardiogram.

RESULTS

The mean age of the population was 62.4 years, with 35% being female and 20% being black. The QTc varied by gender and race (417.9 ± 34.4 ms in men and 433.4 ± 33.6 ms in women, 422.1 ± 34.3 ms in whites and 428.1 ± 36.9 ms in blacks; P < .0001 for both). Risk factors most strongly associated with a prolonged QTc were lower ejection fraction, higher diastolic blood pressure, history of myocardial infarction, and lower glomerular filtration rate. Black race and female gender were also independently associated with a prolonged QTc, after adjustment for cardiac risk factors. Moreover, there was an independent association between QTc and all-cause mortality (hazard ratio 1.037 per 10-ms increase, P < .0001). The increased mortality risk associated with a 10-ms increase in the QTc interval was significantly greater for men compared with women (4.6% vs 2.4%, P = .004) and slightly greater for blacks compared with other races (5.0% vs 3.3%, P = .057).

CONCLUSIONS

Among patients with coronary artery disease, QTc prolongation is independently associated with all-cause mortality. The increased mortality risk is higher for men than for women, with a trend toward higher mortality in blacks.

Comparison of Clinical characteristics and long-term outcomes of patients with ischemic cardiomyopathy with versus without angina pectoris (from the Duke Databank for Cardiovascular Disease)

Myocardial ischemic origin is a significant independent predictor of mortality in patients with heart failure (HF). The implications of angina pectoris (AP) in HF are less well characterized. The aim of this study was to compare the clinical characteristics and outcomes of patients with and without AP in a cohort of patients with reduced ejection fractions and ischemic cardiomyopathy (iCM). Patients who underwent coronary angiography at Duke University Medical Center from January 2000 to September 2009 with ejection fractions <40% and diagnoses of iCM with AP in the previous 6 weeks were compared to similar patients without AP. Time to event was examined using Kaplan-Meier methods for 5 end points: death; death or nonfatal myocardial infarction (MI); death, MI, or revascularization; death or hospitalization; and cardiovascular (CV) death or CV hospitalization. Of 2,376 patients with iCM, 1,412 (59%) had AP. They had more co-morbidities and more previous revascularization than patients without AP. After multivariate adjustment, those with and without AP had similar risks for death (p = 0.32), death or MI (p = 0.15), and death or hospitalization (p = 0.37) (5-year event rates 41% vs 41%, 46% vs 47%, and 87% vs 85%, respectively), but those with AP had lower rates of death, MI, or revascularization (p = 0.01) and higher rates of CV death or CV hospitalization (p = 0.03) (5-year event rates 85% vs 87% and 77% vs 73%, respectively). In conclusion, AP is common in patients with iCM despite medical therapy and previous revascularization and is associated with increased CV death or CV rehospitalization.

Abstract 185: Comparative Efficacy of Revascularization Procedures for severe CAD in patients with Chronic Kidney Disease

Introduction: Patients with Chronic Kidney Disease (CKD) are at increased risk for cardiovascular mortality. However, there are few comparative efficacy studies of coronary revascularization procedures in this high-risk population.

Hypothesis: There is an association between treatment strategy, estimated glomerular filtration rate (eGFR), and survival among patients with CKD and coronary artery disease (CAD).

Methods: We examined patients in the Duke Databank for Cardiovascular Diseases (N=8604) who had significant CAD by cardiac catheterization from 2003-2009. Patients were excluded if they had prior revascularization or if pre-procedure serum creatinine was missing. Patients were stratified by estimated pre-cath estimated glomerular filtration rate (eGFR) into 5 groups: normal (eGFR ≥ 60 ml/min/1.73m 2 ), mild CKD (eGFR 45-59 ml/min/1.73m 2 ), moderate CKD (eGFR 30-44 ml/min/1.73m 2 ), severe CKD (eGFR <30 ml/min/1.73m 2 ) and ESRD (dialysis). Multi-variable Cox Proportional Hazards models were used to determine the association between CKD severity and mortality according to four possible treatment strategies: coronary artery bypass-graft surgery (CABG), PCI with drug eluting stent (DES), PCI with bare metal stent (BMS), or medical management (MED). In addition, we tested for interactions between treatment strategy and eGFR groups.

Results: The sample was mostly male (64.9%, 5591/8604), median age was 62 y (IQR 54-71), and 28.8% (2476/8604) had diabetes. Median follow up was 4.0 y (IQR 2.0-6.1). After adjusting for 17 covariates, baseline eGFR was significantly associated with mortality. For all treatment strategies, there was an inverse association between mortality and each 10ml/min drop in baseline kidney function: MED HR = 1.185 (1.146-1.225), BMS HR = 1.246 (1.190-1.303), DES HR = 1.294 (1.244-1.347), and CABG HR = 1.262 (1.204-1.323). Multivariable models comparing treatment strategies demonstrated differential effects by kidney function (Table; interaction for treatment effect across eGFR groups, p=0.0053). In contrast to BMS, DES and CABG were associated with similar mortality reductions among groups with lower eGFR.

Conclusions: There are strong associations between eGFR and increased mortality among patients with documented CAD, however, these vary significantly by revascularization strategy. These data suggest that a randomized trial of revascularization strategies in patients with CKD may be warranted to guide clinical practice.

Long-term survival of patients with ischemic cardiomyopathy treated by coronary artery bypass grafting versus medical therapy

BACKGROUND

We prospectively applied the Surgical Treatment of Ischemic Cardiomyopathy trial entry criteria to an observational database to determine whether coronary artery bypass grafting (CABG) decreases mortality compared with medical therapy (MED) for patients with coronary artery disease and depressed left ventricular ejection fraction.

METHODS

This was a retrospective, observational, cohort study of prospectively collected data from the Duke Databank for Cardiovascular Disease. Long-term mortality was the main outcome measure. Between January 1, 1995, and July 31, 2009, 86,874 patients underwent cardiac catheterization for suspected ischemic heart disease and were evaluated for inclusion in the analysis.

RESULTS

A total of 2,624 patients were found to have left ventricular ejection fraction less than 0.35, coronary artery disease amenable to CABG, and no left main stenosis of greater than 50%. After exclusions including ongoing Canadian Cardiovascular Society class III angina and acute myocardial infarction, 763 patients were included for propensity score analysis, including 624 who received MED and 139 who underwent CABG. Adjusted mortality curves were constructed for those patients in the three quintiles most likely to receive CABG. The curves diverged early, with risk-adjusted mortality rates at 5 years of 46% for MED versus 29% for CABG, and the survival benefit of CABG over MED continued through 10 years of follow-up (hazard ratio, 0.63; 95% confidence interval, 0.45 to 0.88).

CONCLUSIONS

Among a propensity-matched, risk-adjusted, observational cohort of patients with coronary artery disease, left ventricular ejection fraction less than 0.35, and no left main disease of greater than 50%, CABG is associated with a survival advantage over MED through 10 years of follow-up.

Mode of death and hospitalization from the Second Follow-up Serial Infusions of Nesiritide (FUSION II) trial and comparison of clinical events committee adjudicated versus investigator reported outcomes

The aim of this study was to evaluate the mode of death and hospitalizations in advanced heart failure (HF) patients with renal dysfunction and to examine the rate of concordance between events reported by the clinical events committee and site investigators (using case report forms) in the Second Follow-Up Serial Infusions of Nesiritide (FUSION II) trial. Little is known about the cause of death and hospitalization in patients with advanced HF. FUSION II was a randomized, double-blind, placebo-controlled trial evaluating outpatient nesiritide infusions versus placebo, with 911 patients with advanced HF (New York Heart Association class III or IV) and renal dysfunction enrolled. There were 151 deaths and 1,041 hospitalizations at 24 weeks. The clinical events committee classified events as cardiac, renal, cardiorenal, other or noncardiovascular, or unknown. Kappa statistics and McNemar tests were used to assess agreement (overall and by individual modes of death and hospitalization indications). In conclusion, the most common cause of death or hospitalization was cardiac related, with 70% of deaths and 60% of hospitalizations due to cardiac causes. There was 74% agreement (26% disagreement) on cardiac cause of death (κ = 0.40, McNemar p = 0.001) and 75% agreement (25% disagreement) between the investigators and the clinical events committee on cardiac classification for hospitalization (κ = 0.49, McNemar p <0.0001).

Relationship of the time interval between cardiac catheterization and elective coronary artery bypass surgery with postprocedural acute kidney injury

BACKGROUND

Some prior studies have suggested that the time to cardiac surgery after cardiac catheterization is inversely related to postoperative acute kidney injury (AKI). However, these studies, because of the small number of patients, were unable to adequately account for patient case-mix and included both those undergoing elective surgery and those undergoing urgent surgery.

METHODS AND RESULTS

We examined data on 2441 consecutive patients undergoing elective coronary artery bypass surgery (CABG) after cardiac catheterization. The association of post-CABG AKI (defined as increase in post-CABG serum creatinine ≥ 50% above baseline or the need for new dialysis) and time between cardiac catheterization and CABG was evaluated using multivariable logistic regression modeling. AKI occurred in 17.1% of CABG patients. The risk of AKI was highest in patients in whom CABG was performed ≤ 1 day after cardiac catheterization (adjusted mean rates [95% CI]: 24.0% [18.0%, 30.9%], 18.4% [14.8%, 22.5%], 17.3% [13.3%, 21.9%], 16.4% [12.6%, 20.8%], and 15.8% [13.7%, 18.0%] for days ≤ 1, 2, 3, 4, and ≥ 5, respectively; P=0.019 for test of trend). Post-CABG AKI was associated with increased risk of long-term death (hazard ratio 1.268, 95% CI 1.093, 1.471).

CONCLUSIONS

The risk of post-CABG AKI was inversely and modestly related to the time between cardiac catheterization and CABG, with the highest incidence in those operated ≤ 1 day after cardiac catheterization despite their lower risk profile. Whether delaying elective CABG >24 hours of exposure to contrast agents (when feasible) has the potential for decreasing post-CABG AKI remains to be evaluated in future studies.

Galectin-3 in ambulatory patients with heart failure: results from the HF-ACTION study

BACKGROUND

Galectin-3 is a soluble ß-galactoside-binding lectin released by activated cardiac macrophages. Elevated levels of galectin-3 have been found to be associated with adverse outcomes in patients with heart failure. We evaluated the association between galectin-3 and long-term clinical outcomes in ambulatory heart failure patients enrolled in the HF-ACTION study.

METHODS AND RESULTS

HF-ACTION was a randomized, controlled trial of exercise training in patients with chronic heart failure caused by left ventricular systolic dysfunction. Galectin-3 was assessed at baseline in a cohort of 895 HF-ACTION subjects with stored plasma samples available. The association between galectin-3 and clinical outcomes was assessed using a series of Cox proportional hazards models. Higher galectin-3 levels were associated with other measures of heart failure severity, including higher New York Heart Association class, lower systolic blood pressure, higher creatinine, higher amino-terminal proB-type natriuretic peptide (NTproBNP), and lower maximal oxygen consumption. In unadjusted analysis, there was a significant association between elevated galectin-3 levels and hospitalization-free survival (unadjusted hazard ratio, 1.14 per 3-ng/mL increase in galectin-3; P<0.0001). In multivariable modeling, the prognostic impact of galectin-3 was significantly attenuated by the inclusion of other known predictors, and galectin-3 was no longer a significant predictor after the inclusion of NTproBNP.

CONCLUSIONS

Galectin-3 is elevated in ambulatory heart failure patients and is associated with poor functional capacity and other known measures of heart failure severity. In univariate analysis, galectin-3 was significantly predictive of long-term outcomes, but this association did not persist after adjustment for other predictors, especially NTproBNP.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00047437.

Admission, discharge, or change in B-type natriuretic peptide and long-term outcomes: data from Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure (OPTIMIZE-HF) linked to Medicare claims

BACKGROUND

B-type natriuretic peptide (BNP) has been associated with short- and long-term postdischarge prognosis among hospitalized patients with heart failure. It is unknown if admission, discharge, or change from admission to discharge BNP measure is the most important predictor of long-term outcomes.

METHODS AND RESULTS

We linked patients ≥65 years of age from hospitals in Organized Program to Initiate Lifesaving Treatment in Hospitalized Patients with Heart Failure (OPTIMIZE-HF) to Medicare claims. Among patients with recorded admission and discharge BNP, we compared Cox models predicting 1-year mortality and/or rehospitalization, including clinical variables and clinical variables plus BNP. We calculated the net reclassification improvement (NRI) and integrated discrimination improvement (IDI) for the best-fit model for each outcome versus the model with clinical variables alone. Among 7039 patients in 220 hospitals, median (25th, 75th) admission and discharge BNP were 832 pg/mL (451, 1660) and 534 pg/mL (281, 1111). Observed 1-year mortality and 1-year mortality or rehospitalization rates were 35.2% and 79.4%. The discharge BNP model had the best performance and was the most important characteristic for predicting 1-year mortality (hazard ratio for log transformation, 1.34; 95% confidence interval, 1.28 to 1.40) and 1-year death or rehospitalization (hazard ratio, 1.15; 95% confidence interval, 1.12 to 1.18). Compared with a clinical variables only model, the discharge BNP model improved risk reclassification and discrimination in predicting each outcome (1-year mortality: NRI, 5.5%, P<0.0001; IDI, 0.023, P<0.0001; 1-year mortality or rehospitalization: NRI, 4.2%, P<0.0001; IDI, 0.010, P<0.0001).

CONCLUSIONS

Discharge BNP best predicts 1-year mortality and/or rehospitalization among older patients hospitalized with heart failure. Discharge BNP plus clinical variables modestly improves risk classification and model discrimination for long-term outcomes.