Mental stress-induced left ventricular dysfunction and adverse outcome in ischemic heart disease patients

Aims Mental stress-induced myocardial ischemia (MSIMI) occurs in up to 70% of patients with clinically stable ischemic heart disease and is associated with increased risk of adverse prognosis. We aimed to examine the prognostic value of indices of MSIMI and exercise stress-induced myocardial ischemia (ESIMI) in a population of ischemic heart disease patients that was not confined by having a recent positive physical stress test. Methods and results The Responses of Mental Stress Induced Myocardial Ischemia to Escitalopram Treatment (REMIT) study enrolled 310 subjects who underwent mental and exercise stress testing and were followed annually for a median of four years. Study endpoints included time to first and total rate of major adverse cardiovascular events, defined as all-cause mortality and hospitalizations for cardiovascular causes. Cox and negative binomial regression adjusting for age, sex, resting left ventricular ejection fraction, and heart failure status were used to examine associations of indices of MSIMI and ESIMI with study endpoints. The continuous variable of mental stress-induced left ventricular ejection fraction change was significantly associated with both endpoints (all p values < 0.05). For every reduction of 5% in left ventricular ejection fraction induced by mental stress, patients had a 5% increase in the probability of a major adverse cardiovascular event at the median follow-up time and a 20% increase in the number of major adverse cardiovascular events endured over the follow-up period of six years. Indices of ESIMI did not predict endpoints ( ps > 0.05). Conclusion In patients with stable ischemic heart disease, mental, but not exercise, stress-induced left ventricular ejection fraction change significantly predicts risk of future adverse cardiovascular events.

Incidence and Predictors of Left Atrial Appendage Thrombus in Patients Treated With Nonvitamin K Oral Anticoagulants Versus Warfarin Before Catheter Ablation for Atrial Fibrillation

The utility of routine transesophageal echocardiography (TEE) to exclude left atrial appendage (LAA) thrombus before atrial fibrillation (AF) ablation in patients treated with nonvitamin K oral anticoagulant (NOAC) therapy is unclear. This single-center retrospective study sought to investigate the incidence of LAA thrombus in patients undergoing routine TEE before AF ablation treated with warfarin or NOAC therapy. We included 937 routine pre-AF ablation TEE procedures performed in patients treated with warfarin (n = 517) or NOAC (n = 420). Patients were anticoagulated without interruption for at least 4 consecutive weeks before the TEE. Patients treated with warfarin had lower LAA velocity and underwent TEE earlier in the study period than those treated with NOAC (p <0.05). The incidence of LAA thrombus was higher in patients treated with warfarin (1.55%, 8 of 517) compared with patients treated with NOAC (0.24%, 1 of 420, p = 0.0473 for difference). No LAA thrombus was identified in NOAC-treated patients with a CHA₂DS₂-VASC score <5 and in warfarin-treated patients with a CHA₂DS₂-VASC score <2. TEE-related complications occurred in 3 of 937 procedures (0.3%). In conclusion, LAA thrombus is detected rarely during pre-AF ablation TEE. Treatment with an NOAC is associated with a lower incidence of pre-AF ablation LAA thrombus compared with warfarin.

Sudden Cardiac Death in Patients With Ischemic Heart Failure Undergoing Coronary Artery Bypass Grafting: Results From the STICH Randomized Clinical Trial (Surgical Treatment for Ischemic Heart Failure)

BACKGROUND

The risk of sudden cardiac death (SCD) in patients with heart failure after coronary artery bypass graft surgery (CABG) has not been examined in a contemporary clinical trial of surgical revascularization. This analysis describes the incidence, timing, and clinical predictors of SCD after CABG.

METHODS

Patients enrolled in the STICH trial (Surgical Treatment of Ischemic Heart Failure) who underwent CABG with or without surgical ventricular reconstruction were included. We excluded patients with prior implantable cardioverter-defibrillator and those randomized only to medical therapy. The primary outcome was SCD as adjudicated by a blinded committee. A Cox model was used to examine and identify predictors of SCD. The Fine and Gray method was used to estimate the incidence of SCD accounting for the competing risk of other deaths.

RESULTS

Over a median follow-up of 46 months, 113 of 1411 patients who received CABG without (n = 934) or with (n = 477) surgical ventricular reconstruction had SCD; 311 died of other causes. The mean left ventricular ejection fraction at enrollment was 28±9%. The 5-year cumulative incidence of SCD was 8.5%. Patients who had SCD and those who did not die were younger and had fewer comorbid conditions than did those who died of causes other than SCD. In the first 30 days after CABG, SCD (n=5) accounted for 7% of all deaths. The numerically greatest monthly rate of SCD was in the 31- to 90-day time period. In a multivariable analysis including baseline demographics, risk factors, coronary anatomy, and left ventricular function, end-systolic volume index and B-type natriuretic peptide were most strongly associated with SCD.

CONCLUSIONS

The monthly risk of SCD shortly after CABG among patients with a low left ventricular ejection fraction is highest between the first and third months, suggesting that risk stratification for SCD should occur early in the postoperative period, particularly in patients with increased preoperative end-systolic volume index or B-type natriuretic peptide.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT0002359.

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.

Assessment of cardiac allograft systolic function by global longitudinal strain: From donor to recipient

BACKGROUND

Cardiac allografts are routinely evaluated by left ventricular ejection fraction (LVEF) before and after transplantation. However, myocardial deformation analyses with LV global longitudinal strain (GLS) are more sensitive for detecting impaired LV myocardial systolic performance compared with LVEF.

METHODS

We analyzed echocardiograms in 34 heart donor-recipient pairs transplanted at Duke University from 2000 to 2013. Assessments of allograft LV systolic function by LVEF and/or LV GLS were performed on echocardiograms obtained pre-explanation in donors and serially in corresponding recipients.

RESULTS

Donors had a median LVEF of 55% (25th, 75th percentile, 54% to 60%). Median donor LV GLS was -14.6% (-13.7 to -17.3%); LV GLS was abnormal (ie, >-16%) in 68% of donors. Post-transplantation, LV GLS was further impaired at 6 weeks (median -11.8%; -11.0 to -13.4%) and 3 months (median -11.4%; -10.3 to -13.9%) before recovering to pretransplant levels in follow-up. Median LVEF remained ≥50% throughout follow-up. We found no association between donor LV GLS and post-transplant outcomes, including all-cause hospitalization and mortality.

CONCLUSIONS

GLS demonstrates allograft LV systolic dysfunction in donors and recipients not detected by LVEF. The clinical implications of subclinical allograft dysfunction detected by LV GLS require further study.

Impaired left ventricular global longitudinal strain in patients with heart failure with preserved ejection fraction: insights from the RELAX trial

BACKGROUND

While abnormal left ventricular (LV) global longitudinal strain (GLS) has been described in patients with heart failure with preserved ejection fraction (HFpEF), its prevalence and clinical significance are poorly understood.

METHODS AND RESULTS

Patients enrolled in the RELAX trial of sildenafil in HFpEF (LV ejection fraction ≥50%) in whom two-dimensional, speckle-tracking LV GLS was possible (n = 187) were analysed. The distribution of LV GLS and its associations with clinical characteristics, LV structure and function, biomarkers, exercise capacity and quality of life were assessed. Baseline median LV GLS was -14.6% (25th and 75th percentile, -17.0% and -11.9%, respectively) and abnormal (≥ - 16%) in 122/187 (65%) patients. Patients in the tertile with the best LV GLS had lower N-terminal pro-brain natriuretic peptide (NT-proBNP) [median 505 pg/mL (161, 1065) vs. 875 pg/mL (488, 1802), P = 0.008) and lower collagen III N-terminal propeptide (PIIINP) levels [median 6.7 µg/L (5.1, 8.1) vs. 8.1 µg/L (6.5, 10.5), P = 0.001] compared with the tertile with the worst LV GLS. There was also a modest linear relationship with LV GLS and log-transformed NT-proBNP and PIIINP (r = 0.29, P < 0.001 and r = 0.19, P = 0.009, respectively). We observed no linear association of LV GLS with Minnesota Living with Heart Failure scores, 6-min walk distance, peak oxygen consumption, or expiratory minute ventilation/carbon dioxide excretion slope.

CONCLUSIONS

Impaired LV GLS is common among HFpEF patients, indicating the presence of covert systolic dysfunction despite normal LV ejection fraction. Impaired LV GLS was associated with biomarkers of wall stress and collagen synthesis and diastolic dysfunction but not with quality of life or exercise capacity, suggesting other processes may be more responsible for these aspects of the HFpEF syndrome.

Associations between positive emotional well-being and stress-induced myocardial ischemia: Well-being scores predict exercise-induced ischemia

OBJECTIVE

Depressive symptoms have been associated with myocardial ischemia induced by mental (MSIMI) and exercise (ESIMI) stress in clinically stable ischemic heart disease (IHD) patients, but the association between positive emotions and inducible ischemia is less well characterized. The objective of this study was to examine the associations between ratings of well-being and stress-induced ischemia.

METHODS

Subjects were adult patients with documented IHD underwent mental and exercise stress testing for the Responses of Myocardial Ischemia to Escitalopram Treatment (REMIT) trial. The General Well-Being Schedule (GWBS), with higher scores reflecting greater subjective well-being, and the Center for Epidemiologic Studies Depression Scale (CES-D) were obtained from the REMIT participants. Echocardiography was used to measure ischemic responses to mental stress and Bruce protocol treadmill exercise testing. Data were analyzed using logistic regression adjusting for age, sex, resting left-ventricular ejection fraction (LVEF), and resting wall motion score index, as well as health-related behaviors.

RESULTS

GWBS scores were obtained for 210 individuals, with MSIMI present in 92 (43.8%) and ESIMI present in 64 (30.5%). There was a significant inverse correlation between GWBS-PE (Positive Emotion subscale) scores and probability of ESIMI (OR=0.55 (95%CI 0.36-0.83), p=0.005). This association persisted after additional control for CESD subscales measuring negative and positive emotions and for variables reflecting health-related behaviors. A similar inverse correlation between GWBS-PE and MSIMI was observed, but did not reach statistical significance (OR=0.81 (95%CI 0.54-1.20), p=0.28).

CONCLUSION

This is, to our knowledge, the first study demonstrating that greater levels of self-reported positive emotions are associated with a lower likelihood of ESIMI among patients with known IHD. Our results highlight the important interface functions of the central nervous and cardiovascular systems and underscore areas for future investigation.

Markers of Atherosclerosis, Clinical Characteristics, and Treatment Patterns in Heart Failure: A Case-Control Study of Middle-Aged Adult Heart Failure Patients in Rural Kenya

BACKGROUND

Although risk factors for heart failure are increasingly common worldwide, the contribution of atherosclerosis to heart failure in sub-Saharan Africa is largely unknown.

OBJECTIVE

This study assessed the association between atherosclerotic risk factors and heart failure in a developing country.

METHODS

We performed a case-control study of heart failure in rural Kenya. We assessed the risk factors for heart failure by using international criteria based on electrocardiogram (ECG), echocardiogram, physical examination findings, and laboratory testing. Atherosclerotic risk factors were determined by ECG, echocardiogram, ankle-brachial index (ABI), and lipid testing. We described the relationship of wall motion abnormalities on echocardiogram, ABI <0.9, and ischemic pattern on ECG with the presence of heart failure with multivariable logistic regression adjusting for age and sex and using adjusted odds ratios (AORs) and 95% confidence intervals (CIs).

RESULTS

There were 125 cases and 191 controls (n = 316); 49% were male. The mean age was 60 (SD = 13) years. Most patients had hypertension (53%), and 16% had human immunodeficiency virus infection. Lipids were in the normal range for all. Cases were older than controls (62 years vs. 58 years, respectively). The most common abnormality associated with heart failure was dilated cardiomyopathy. Ischemic heart failure was the second most common cause in men. Cases were more likely to have an ABI <0.9 (46% vs. 31%; AOR: 1.99; 95% CI: 1.19 to 3.32), ischemia or infarct on ECG (68% vs. 43%; AOR: 3.01; 95% CI: 1.43 to 6.34), and wall motion abnormalities on echocardiogram (54% vs. 15%; AOR: 7.00; 95% CI: 3.95 to 12.39).

CONCLUSIONS

Ischemic heart failure is more common in Kenya than previously recognized. Noninvasive markers of atherosclerosis are routinely found among patients with heart failure. Treatment and prevention of heart failure in sub-Saharan Africa must consider many causes including those related to atherosclerosis.

Reassessment of Cardiac Function and Implantable Cardioverter-Defibrillator Use Among Medicare Patients With Low Ejection Fraction After Myocardial Infarction

Background:

Guidelines recommend that patients with low ejection fraction (EF) after myocardial infarction (MI) have their EF reassessed 40 days after MI for implantable cardioverter-defibrillator (ICD) candidacy. This study examines rates of EF reassessment and their association with 1-year ICD implantation in post-MI patients with low EF.

Methods:

We examined rates of postdischarge EF reassessment and ICD implantation among 10 289 Medicare-insured patients ≥65 years of age with an EF≤35% during the index MI admission from January 2007 through September 2010 in ACTION Registry–GWTG (Acute Coronary Treatment and Intervention Outcomes Network Registry – Get With The Guidelines). Multivariable Cox models tested the association between time-dependent EF reassessment and 1-year ICD implantation, stratified by revascularization status during the index MI admission.

Results:

Among patients with EF ≤35% during the index MI admission, 66.8% (95% confidence interval [CI], 65.9–67.8) had EF reassessment within the next year. Revascularized patients were more likely to have EF reassessment (76.9% [95% CI, 75.8–78.0)] versus 53.7% [95% CI, 52.2–55.2]; P <0.001) and had shorter times to EF reassessment (median, 67 versus 84 days; P <0.001) than nonrevascularized patients. Among patients with EF reassessment, only 11% received an ICD within 1 year. Reassessment of EF was associated with a higher likelihood of ICD implantation for both revascularized (unadjusted, 12.1% versus 2.4%, P <0.001; adjusted hazard ratio, 10.6, 95% CI, 7.7–14.8) and nonrevascularized (unadjusted, 10.0% versus 1.7%, P <0.001; adjusted hazard ratio, 6.1, 95% CI, 4.1–9.2) patients.

Conclusions:

In US practice, EF reassessments are commonly performed among patients with MI with an initially reduced EF. Although 1-year EF reassessment is associated with increased likelihood of ICD implantation, 1-year ICD implantation rates remain very low even among patients with EF reassessment, regardless of revascularization status.

Approaches to Sustainable Capacity Building for Cardiovascular Disease Care in Kenya

Cardiovascular diseases are approaching epidemic levels in Kenya and other low- and middle-income countries without accompanying effective preventive and therapeutic strategies. This is happening in the background of residual and emerging infections and other diseases of poverty, and increasing physical injuries from traffic accidents and noncommunicable diseases. Investments to create a skilled workforce and health care infrastructure are needed. Improving diagnostic capacity, access to high-quality medications, health care, appropriate legislation, and proper coordination are key components to ensuring the reversal of the epidemic and a healthy citizenry. Strong partnerships with the developed countries also crucial.

Clinical and echocardiographic predictors of mortality in acute pulmonary embolism

PURPOSE

The aim of this study was to evaluate the utility of adding quantitative assessments of cardiac function from echocardiography to clinical factors in predicting the outcome of patients with acute pulmonary embolism (PE).

METHODS

Patients with a diagnosis of acute PE, based on a positive ventilation perfusion scan or computed tomography (CT) chest angiogram, were identified using the Duke University Hospital Database. Of these, 69 had echocardiograms within 24-48 h of the diagnosis that were suitable for offline analysis. Clinical features that were analyzed included age, gender, body mass index, vital signs and comorbidities. Echocardiographic parameters that were analyzed included left ventricular (LV) ejection fraction (EF), regional, free wall and global RV speckle-tracking strain, RV fraction area change (RVFAC), Tricuspid Annular Plane Systolic Excursion (TAPSE), pulmonary artery acceleration time (PAAT) and RV myocardial performance (Tei) index. Univariable and multivariable regression statistical analysis models were used.

RESULTS

Out of 69 patients with acute PE, the median age was 55 and 48 % were female. The median body mass index (BMI) was 27 kg/m². Twenty-nine percent of the cohort had a history of cancer, with a significant increase in cancer prevalence in non-survivors (57 % vs 29 %, p = 0.02). Clinical parameters including heart rate, respiratory rate, troponin T level, active malignancy, hypertension and COPD were higher among non-survivors when compared to survivors (p ≤ 0.05). Using univariable analysis, NYHA class III symptoms, hypoxemia on presentation, tachycardia, tachypnea, elevation in Troponin T, absence of hypertension, active malignancy and chronic obstructive pulmonary disease (COPD) were increased in non-survivors compared to survivors (p ≤ 0.05). In multivariable models, RV Tei Index, global and free (lateral) wall RVLS were found to be negatively associated with survival probability after adjusting for age, gender and systolic blood pressure (p ≤ 0.05).

CONCLUSION

The addition of echocardiographic assessment of RV function to clinical parameters improved the prediction of outcomes for patients with acute PE. Larger studies are needed to validate these findings.

Ten-Year Outcomes After Coronary Artery Bypass Grafting According to Age in Patients With Heart Failure and Left Ventricular Systolic Dysfunction: An Analysis of the Extended Follow-Up of the STICH Trial (Surgical Treatment for Ischemic Heart Failure)

BACKGROUND

Advancing age is associated with a greater prevalence of coronary artery disease in heart failure with reduced ejection fraction and with a higher risk of complications after coronary artery bypass grafting (CABG). Whether the efficacy of CABG compared with medical therapy (MED) in patients with heart failure caused by ischemic cardiomyopathy is the same in patients of different ages is unknown.

METHODS

A total of 1212 patients (median follow-up, 9.8 years) with ejection fraction ≤35% and coronary disease amenable to CABG were randomized to CABG or MED in the STICH trial (Surgical Treatment for Ischemic Heart Failure).

RESULTS

Mean age at trial entry was 60 years; 12% were women; 36% were nonwhite; and the baseline ejection fraction was 28%. For the present analyses, patients were categorized by age quartiles: quartile 1, ≤54 years; quartile, 2 >54 and ≤60 years; quartile 3, >60 and ≤67 years; and quartile 4, >67 years. Older versus younger patients had more comorbidities. All-cause mortality was higher in older compared with younger patients assigned to MED (79% versus 60% for quartiles 4 and 1, respectively; log-rank P=0.005) and CABG (68% versus 48% for quartiles 4 and 1, respectively; log-rank P<0.001). In contrast, cardiovascular mortality was not statistically significantly different across the spectrum of age in the MED group (53% versus 49% for quartiles 4 and 1, respectively; log-rank P=0.388) or CABG group (39% versus 35% for quartiles 4 and 1, respectively; log-rank P=0.103). Cardiovascular deaths accounted for a greater proportion of deaths in the youngest versus oldest quartile (79% versus 62%). The effect of CABG versus MED on all-cause mortality tended to diminish with increasing age (P_interaction=0.062), whereas the benefit of CABG on cardiovascular mortality was consistent over all ages (P_interaction=0.307). There was a greater reduction in all-cause mortality or cardiovascular hospitalization with CABG versus MED in younger compared with older patients (P_interaction=0.004). In the CABG group, cardiopulmonary bypass time or days in intensive care did not differ for older versus younger patients.

CONCLUSIONS

CABG added to MED has a more substantial benefit on all-cause mortality and the combination of all-cause mortality and cardiovascular hospitalization in younger compared with older patients. CABG added to MED has a consistent beneficial effect on cardiovascular mortality regardless of age.

CLINICAL TRIAL REGISTRATION

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

Metabolomic Profiling Identifies Novel Circulating Biomarkers of Mitochondrial Dysfunction Differentially Elevated in Heart Failure With Preserved Versus Reduced Ejection Fraction: Evidence for Shared Metabolic Impairments in Clinical Heart Failure

BACKGROUND

Metabolic impairment is an important contributor to heart failure (HF) pathogenesis and progression. Dysregulated metabolic pathways remain poorly characterized in patients with HF and preserved ejection fraction (HFpEF). We sought to determine metabolic abnormalities in HFpEF and identify pathways differentially altered in HFpEF versus HF with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

We identified HFpEF cases, HFrEF controls, and no-HF controls from the CATHGEN study of sequential patients undergoing cardiac catheterization. HFpEF cases (N=282) were defined by left ventricular ejection fraction (LVEF) ≥45%, diastolic dysfunction grade ≥1, and history of HF; HFrEF controls (N=279) were defined similarly, except for having LVEF <45%. No-HF controls (N=191) had LVEF ≥45%, normal diastolic function, and no HF diagnosis. Targeted mass spectrometry and enzymatic assays were used to quantify 63 metabolites in fasting plasma. Principal components analysis reduced the 63 metabolites to uncorrelated factors, which were compared across groups using ANCOVA. In basic and fully adjusted models, long-chain acylcarnitine factor levels differed significantly across groups (P<0.0001) and were greater in HFrEF than HFpEF (P=0.0004), both of which were greater than no-HF controls. We confirmed these findings in sensitivity analyses using stricter inclusion criteria, alternative LVEF thresholds, and adjustment for insulin resistance.

CONCLUSIONS

We identified novel circulating metabolites reflecting impaired or dysregulated fatty acid oxidation that are independently associated with HF and differentially elevated in HFpEF and HFrEF. These results elucidate a specific metabolic pathway in HF and suggest a shared metabolic mechanism in HF along the LVEF spectrum.

Implementing a Continuous Quality Improvement Program in a High-Volume Clinical Echocardiography Laboratory: Improving Care for Patients With Aortic Stenosis

BACKGROUND

The management of aortic stenosis rests on accurate echocardiographic diagnosis. Hence, it was chosen as a test case to examine the utility of continuous quality improvement (CQI) approaches to increase echocardiographic data accuracy and reliability. A novel, multistep CQI program was designed and prospectively used to investigate whether it could minimize the difference in aortic valve mean gradients reported by echocardiography when compared with cardiac catheterization.

METHODS AND RESULTS

The Duke Echo Laboratory compiled a multidisciplinary CQI team including 4 senior sonographers and MD faculty to develop a mapped CQI process that incorporated Intersocietal Accreditation Commission standards. Quarterly, the CQI team reviewed all moderate- or greater-severity aortic stenosis echocardiography studies with concomitant catheterization data, and deidentified individual and group results were shared at meetings attended by cardiologists and sonographers. After review of 2011 data, the CQI team proposed specific amendments implemented over 2012: the use of nontraditional imaging and Doppler windows as well as evaluation of aortic gradients by a second sonographer. The primary outcome measure was agreement between catheterization- and echocardiography-derived mean gradients calculated by using the coverage probability index with a prespecified acceptable echocardiography-catheterization difference of <10 mm Hg in mean gradient. Between January 2011 and January 2014, 2093 echocardiograms reported moderate or greater aortic stenosis. Among cases with available catheterization data pre- and post-CQI, the coverage probability index increased from 54% to 70% (P=0.03; 98 cases, year 2011; 70 cases, year 2013). The proportion of patients referred for invasive valve hemodynamics decreased from 47% pre-CQI to 19% post-CQI (P<0.001).

CONCLUSIONS

A laboratory practice pattern that was amenable to reform was identified, and a multistep modification was designed and implemented that produced clinically valuable performance improvements. The new protocol improved aortic stenosis mean gradient agreement between echocardiography and catheterization and was associated with a measurable decrease in referrals of patients for invasive studies.

Predicting Outcomes Over Time in Patients With Heart Failure, Left Ventricular Systolic Dysfunction, or Both Following Acute Myocardial Infarction

Background

Most studies of risk assessment or stratification in patients with myocardial infarction (MI) have been static and fail to account for the evolving nature of clinical events and care processes. We sought to identify predictors of mortality, cardiovascular death or nonfatal MI, and cardiovascular death or nonfatal heart failure (HF) over time in patients with HF, left ventricular systolic dysfunction, or both post‐MI.

Methods and Results

Using data from the VALsartan In Acute myocardial iNfarcTion (VALIANT) trial, we developed models to estimate the association between patient characteristics and the likelihood of experiencing an event from the time of a follow‐up visit until the next visit. The intervals are: hospital arrival to discharge or 14 days, whichever occurs first; hospital discharge to 30 days; 30 days to 6 months; and 6 months to 3 years. Models were also developed to predict the entire 3‐year follow‐up period using baseline information. Multivariable Cox proportional hazards modeling was used throughout with Wald chi‐squares as the comparator of strength for each predictor. For the baseline model of overall mortality, the 3 strongest predictors were age (adjusted hazard ratio [HR], 1.35; 95% CI, 1.28–1.42; P<0.0001), baseline heart rate (adjusted HR, 1.17; 95% CI, 1.14–1.21; P<0.0001), and creatinine clearance (≤100 mL/min; adjusted HR, 0.86; 95% CI, 0.84–0.89; P<0.0001). According to the integrated discrimination improvement (IDI) and net reclassification improvement (NRI) indices, the updated model had significant improvement over the model with baseline covariates only in all follow‐up periods and with all outcomes.

Conclusions

Patient information assessed closest to the time of the outcome was more valuable in predicting death when compared with information obtained at the time of the index hospitalization. Using updated patient information improves prognosis over using only the information available at the time of the index event.

Human Immunodeficiency Virus and Heart Failure in Low- and Middle-Income Countries

Successful combination therapy for human immunodeficiency virus (HIV) has transformed this disease from a short-lived infection with high mortality to a chronic disease associated with increasing life expectancy. This is true for high- as well as low- and middle-income countries. As a result of this increased life expectancy, people living with HIV are now at risk of developing other chronic diseases associated with aging. Heart failure has been common among people living with HIV in the eras of pre- and post- availability of antiretroviral therapy; however, our current understanding of the pathogenesis and approaches to management have not been systematically addressed. HIV may cause heart failure through direct (e.g., viral replication, mitochondrial dysfunction, cardiac autoimmunity, autonomic dysfunction) and indirect (e.g., opportunistic infections, antiretroviral therapy, alcohol abuse, micronutrient deficiency, tobacco use) pathways. In low- and middle-income countries, 2 large observational studies have recently reported clinical characteristics and outcomes in these patients. HIV-associated heart failure remains a common cardiac diagnosis in people living with heart failure, yet a unifying set of diagnostic criteria is lacking. Treatment patterns for heart failure fall short of society guidelines. Although there may be promise in cardiac glycosides for treating heart failure in people living with HIV, clinical studies are needed to validate in vitro findings. Owing to the burden of HIV in low- and middle-income countries and the concurrent rise of traditional cardiovascular risk factors, strategic and concerted efforts in this area are likely to impact the care of people living with HIV around the globe.

Effect of single and dual renin-angiotensin blockade on stroke in patients with and without diabetes in VALIANT

Introduction

Concern has been raised about a possible increase in risk of stroke in patients with diabetes treated with the combination of the renin-inhibitor aliskiren and an angiotensin converting enzyme inhibitor or angiotensin receptor blocker. We compared the rate of stroke in patients with and without diabetes treated with single or dual renin-angiotensin system blockade after acute myocardial infarction.

Patients and methods

We performed a post hoc analysis of the Valsartan in Acute Myocardial Infarction trial in which 14,703 patients with heart failure, left ventricular systolic dysfunction or both, were randomised to captopril (C), valsartan (V) or both (C + V) after 0.5-10 days after acute myocardial infarction and followed for a median of 2.1 years. We used Cox proportional-hazard regression to estimate the hazard ratios [HR (95% CI)] of stroke in each treatment group.

Results

Among patients with diabetes, 60/1303 (4.6%) receiving captopril, 60/1337 (4.5%) valsartan and 41/1340 (3.1%) valsartan plus captopril suffered a stroke: V + C versus V or C HR 0.68 (0.47-0.96), p = 0.03. The corresponding numbers in patients without diabetes were 106/3606 (2.9%), 97/3572 (2.7%) and 99/3545 (2.8%): V + C versus V or C HR 0.99 (0.78-1.26), p = 0.92 (interaction p = 0.08).

Conclusion

The risk of stroke after myocardial infarction in patients with diabetes was lower in patients treated with both an angiotensin converting enzyme inhibitor and angiotensin receptor blocker than in patients receiving either monotherapy.

Platypnea-Orthodeoxia Syndrome: To Shunt or Not to Shunt, That is the Question

Platypnea-orthodeoxia syndrome is a rare disease defined by dyspnea and deoxygenation, induced by an upright position, and relieved by recumbency. Causes include shunting through a patent foramen ovale and pulmonary arteriovenous malformations. A 79-year-old woman experienced 2 syncopal episodes at rest and presented at another hospital. In the emergency department, she was hypoxic, needing 6 L/min of oxygen. Her chest radiograph showed nothing unusual. Transthoracic echocardiograms with saline microcavitation evaluation were mildly positive early after agitated-saline administration, suggesting intracardiac shunting. She was then transferred to our center. Right-sided heart catheterization revealed no oximetric evidence of intracardiac shunting while the patient was supine and had a low right atrial pressure. However, her oxygen saturation dropped to 78% when she sat up. Repeat transthoracic echocardiography while sitting revealed a dramatically positive early saline microcavitation-uptake into the left side of the heart. Transesophageal echocardiograms showed a patent foramen ovale, with right-to-left shunting highly dependent upon body position. The patient underwent successful percutaneous patent foramen ovale closure, and her oxygen supplementation was suspended. In patients with unexplained or transient hypoxemia in which a cardiac cause is suspected, it is important to evaluate shunting in both the recumbent and upright positions. In this syndrome, elevated right atrial pressure is not necessary for significant right-to-left shunting. Percutaneous closure, if feasible, is first-line therapy in these patients.

Coronary-Artery Bypass Surgery in Patients with Ischemic Cardiomyopathy

BACKGROUND

The survival benefit of a strategy of coronary-artery bypass grafting (CABG) added to guideline-directed medical therapy, as compared with medical therapy alone, in patients with coronary artery disease, heart failure, and severe left ventricular systolic dysfunction remains unclear.

METHODS

From July 2002 to May 2007, a total of 1212 patients with an ejection fraction of 35% or less and coronary artery disease amenable to CABG were randomly assigned to undergo CABG plus medical therapy (CABG group, 610 patients) or medical therapy alone (medical-therapy group, 602 patients). The primary outcome was death from any cause. Major secondary outcomes included death from cardiovascular causes and death from any cause or hospitalization for cardiovascular causes. The median duration of follow-up, including the current extended-follow-up study, was 9.8 years.

RESULTS

A primary outcome event occurred in 359 patients (58.9%) in the CABG group and in 398 patients (66.1%) in the medical-therapy group (hazard ratio with CABG vs. medical therapy, 0.84; 95% confidence interval [CI], 0.73 to 0.97; P=0.02 by log-rank test). A total of 247 patients (40.5%) in the CABG group and 297 patients (49.3%) in the medical-therapy group died from cardiovascular causes (hazard ratio, 0.79; 95% CI, 0.66 to 0.93; P=0.006 by log-rank test). Death from any cause or hospitalization for cardiovascular causes occurred in 467 patients (76.6%) in the CABG group and in 524 patients (87.0%) in the medical-therapy group (hazard ratio, 0.72; 95% CI, 0.64 to 0.82; P<0.001 by log-rank test).

CONCLUSIONS

In a cohort of patients with ischemic cardiomyopathy, the rates of death from any cause, death from cardiovascular causes, and death from any cause or hospitalization for cardiovascular causes were significantly lower over 10 years among patients who underwent CABG in addition to receiving medical therapy than among those who received medical therapy alone. (Funded by the National Institutes of Health; STICH [and STICHES] ClinicalTrials.gov number, NCT00023595.).

Building Sustainable Capacity for Cardiovascular Care at a Public Hospital in Western Kenya

Cardiovascular disease deaths are increasing in low- and middle-income countries and are exacerbated by health care systems that are ill-equipped to manage chronic diseases. Global health partnerships, which have stemmed the tide of infectious diseases in low- and middle-income countries, can be similarly applied to address cardiovascular diseases. In this review, we present the experiences of an academic partnership between North American and Kenyan medical centers to improve cardiovascular health in a national public referral hospital. We highlight our stepwise approach to developing sustainable cardiovascular services using the health system strengthening World Health Organization Framework for Action. The building blocks of this framework (leadership and governance, health workforce, health service delivery, health financing, access to essential medicines, and health information system) guided our comprehensive and sustainable approach to delivering subspecialty care in a resource-limited setting. Our experiences may guide the development of similar collaborations in other settings.

An Approach to Improve the Negative Predictive Value and Clinical Utility of Transthoracic Echocardiography in Suspected Native Valve Infective Endocarditis

BACKGROUND

In patients with suspected native valve infective endocarditis, current guidelines recommend initial transthoracic echocardiography (TTE) followed by transesophageal echocardiography (TEE) if clinical suspicion remains. The guidelines do not account for the quality of initial TTE or other findings that may alter the study's diagnostic characteristics. This may lead to unnecessary TEE when initial TTE was sufficient to rule out vegetation.

METHODS

The objective of this study was to determine if the use of a strict definition of negative results on TTE would improve the performance characteristics of TTE sufficiently to exclude vegetation. A retrospective analysis of patients at a single institution with suspected native valve endocarditis who underwent TTE followed by TEE within 7 days between January 1, 2007, and February 28, 2014, was performed. Negative results on TTE for vegetation were defined by either the standard approach (no evidence of vegetation seen on TTE) or by applying a set of strict negative criteria incorporating other findings on TTE. Using TEE as the gold standard for the presence of vegetation, the diagnostic performance of the two transthoracic approaches was compared.

RESULTS

In total, 790 pairs of TTE and TEE were identified. With the standard approach, 661 of the transthoracic studies had negative findings (no vegetation seen), compared with 104 studies with negative findings using the strict negative approach (meeting all strict negative criteria). The sensitivity and negative predictive value of TTE for detecting vegetation were substantially improved using the strict negative approach (sensitivity, 98% [95% CI, 95%-99%] vs 43% [95% CI, 36%-51%]; negative predictive value, 97% [95% CI, 92%-99%] vs 87% [95% CI, 84%-89%]).

CONCLUSIONS

The ability of TTE to exclude vegetation in patients is excellent when strict criteria for negative results are applied. In patients at low to intermediate risk with strict negative results on TTE, follow-up TEE may be unnecessary.

Getting to a Man's Heart through His Colon

A 69-year-old man presented with a progressively enlarging pulsatile mass in the left side of his chest. Because of a history of an ischemic cardiomyopathy, he had been randomized in 2003 to undergo coronary artery bypass grafting with a Dor procedure, as part of the Surgical Treatment for Ischemic Heart Failure (STICH) trial. Our patient's imaging studies, including a thoracic computed tomogram and transthoracic echocardiogram, were now of concern for left ventricular pseudoaneurysm. He was taken immediately for surgical exploration. Purulent material, with empyema, extended from the anterior chest wall through the chest cavity into the mediastinum, with communication into the pericardial space. Notably, there was no compromise of the left ventricular cavity, and there was no pseudoaneurysm. The chest was copiously irrigated before closure. The epicardial patch placed 10 years earlier in the STICH trial was not thought to be the nidus of the abscess and was therefore not removed. Three months later, the patient presented again, this time with hemorrhagic shock and bleeding from his left anterior thoracotomy site, which we then re-entered. He was found to have a left ventricular pseudoaneurysm with disruption of the ventricular apex. The epicardial felt-and-Dacron patch, placed 10 years previously during his Dor procedure, was found to be infected with Clostridium difficile and was removed. The left ventricular apex was repaired. Whereas C. difficile bacteremia is rare, the seeding of prosthetic cardiac material with delayed presentation, as in this case, is extraordinarily uncommon.

Cardiovascular Outcomes According to Systolic Blood Pressure in Patients With and Without Diabetes: An ACCOMPLISH Substudy

To evaluate the effects of achieved systolic blood pressure (SBP) during treatment on cardiovascular (CV) outcomes, the authors measured event rates of a composite primary endpoint (CV death or nonfatal myocardial infarction or stroke) at on-treatment SBPs of ≥140 mm Hg and the 10 mm Hg intervals of <140 mm Hg, <130 mm Hg, and <120 mm Hg in 6459 patients with diabetes (mean age, 67) and 4246 patients without diabetes (mean age, 69) from the Avoiding Cardiovascular Events in Combination Therapy in Patients Living With Systolic Hypertension (ACCOMPLISH) trial. In the diabetic cohort, the primary endpoint was 49% lower (P<.001) at <140 mm Hg than at ≥140 mm Hg, and the separate components of this endpoint were also significantly reduced. Further SBP reductions did not improve outcomes, and at <120 mm Hg they were no longer different (except for stroke) from ≥140 mm Hg. In contrast, in the nondiabetic cohort, the primary endpoint event rate fell steadily (although not significantly) through the decreasing SBP categories until it was reduced by 45% (P=.0413) at <120 mm Hg. Total stroke rates for both the diabetic (-56%, P=.0120) and nondiabetic (-68%, P=.0067) cohorts were lowest at <120 mm Hg, and adverse renal events (serum creatinine increase ≥50%) were significantly lowest in the range of 130 mm Hg to 139 mm Hg for both cohorts. Diabetic patients (<140 mm Hg or <130 mm Hg) and nondiabetic patients (<120 mm Hg) may require different SBP targets for optimal CV protection, although stroke and renal considerations should also influence the selection of blood pressure targets.

Relation of Elevated Heart Rate in Patients With Heart Failure With Reduced Ejection Fraction to One-Year Outcomes and Costs

There are limited data describing outcomes associated with an elevated heart rate in patients with heart failure with reduced ejection fraction (HFrEF) in routine clinical practice. We identified patients with HFrEF at Duke University Hospital undergoing echocardiograms and heart rate assessments without paced rhythms or atrial fibrillation. Outcomes (all-cause mortality or hospitalization and medical costs per day alive) were assessed using electronic medical records, hospital cost accounting data, and national death records. Patients were stratified by heart rate (<70 and ≥70 beats/min) and compared using generalized linear models specified with gamma error distributions and log links for costs and proportional hazard models for mortality/hospitalization. Of 722 eligible patients, 582 patients (81%) were treated with β blockers. The median heart rate was 81 beats/min (25th and 75th percentiles 69 to 96) and 527 patients (73%) had a heart rate ≥70 beats/min. After multivariate adjustment, a heart rate ≥70 beats/min was associated with increased 1-year all-cause mortality or hospitalization, hazard ratio 1.37 (95% CI 1.07 to 1.75) and increased medical costs per day alive, cost ratio 2.03 (95% CI 1.53 to 2.69). In conclusion, at a large tertiary care center, despite broad use of β blockers, a heart rate ≥70 beats/min was observed in 73% of patients with HFrEF and associated with worse 1-year outcomes and increased direct medical costs per day alive.