Impact of Advanced Therapy Centers on Characteristics and Outcomes of Heart Failure Admissions

BACKGROUND

Although much attention has been paid to admission and transfer patterns for cardiogenic shock, contemporary data are lacking on decompensated heart failure (HF) admissions and transfers and the impact of advanced therapy centers (ATCs) on outcomes.

METHODS

HF hospitalizations were obtained from the Nationwide Readmissions Database 2016 to 2019. Centers performing at least 1 heart transplant or left ventricular assist device were classified as ATCs. Patient characteristics, outcomes, and procedural volume were compared among 3 cohorts: admissions to non-ATCs, admissions to ATCs, and transfers to ATCs. A secondary analysis evaluated outcomes for severe HF hospitalizations (cardiogenic shock, cardiac arrest, and mechanical ventilation). Multivariable logistic regression was performed to adjust for the presence of HF decompensations and significant clinical variables during univariate analysis.

RESULTS

A total of 2 331 690 hospitalizations (81.2%) were admissions to non-ATCs (94.5% of centers), 525 037 (18.3%) were admissions to ATCs (5.5% of centers), and 15 541 (0.5%) were transferred to ATCs. Patients treated at ATCs (especially those transferred) had higher rates of HF decompensations, procedural frequency, lengths of stay, and costs. Unadjusted mortality was 2.6% at non-ATCs and was higher at ATCs, both for directly admitted (2.9%, P<0.001) and transferred (11.2%, P<0.001) patients. However, multivariable-adjusted mortality was significantly lower at ATCs, both for directly admitted (odds ratio, 0.82 [95% CI, 0.78-0.87]; P<0.001) and transferred (odds ratio, 0.66 [95% CI, 0.57-0.78]; P<0.001) patients. For severe HF admissions, unadjusted mortality was 37.2% at non-ATCs and was lower at ATCs, both for directly admitted (25.3%, P<0.001) and transferred (25.2%, P<0.001) patients, with similarly lower multivariable-adjusted mortality.

CONCLUSIONS

Patients with HF treated at ATCs were sicker but associated with higher procedural volume and lower adjusted mortality.

Impella Versus Intra-Aortic Balloon Pump in Patients With Cardiogenic Shock Treated With Venoarterial Extracorporeal Membrane Oxygenation: An Observational Study

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used for patients with cardiogenic shock. Although Impella or intra-aortic balloon pump (IABP) is frequently used for left ventricular unloading (LVU) during VA-ECMO treatment, there are limited data on comparative outcomes. We compared outcomes of Impella and IABP for LVU during VA-ECMO.

METHODS AND RESULTS

Using the Nationwide Readmissions Database between 2016 and 2020, we analyzed outcomes in 3 groups of patients with cardiogenic shock requiring VA-ECMO based on LVU strategies: extracorporeal membrane oxygenation (ECMO) only, ECMO with IABP, and ECMO with Impella. Of 15 980 patients on VA-ECMO, IABP and Impella were used in 19.4% and 16.4%, respectively. The proportion of patients receiving Impella significantly increased from 2016 to 2020 (6.5% versus 25.8%; P-trend<0.001). In-hospital mortality was higher with ECMO with Impella (54.8%) compared with ECMO only (50.4%) and ECMO with IABP (48.4%). After adjustment, ECMO with IABP versus ECMO only was associated with lower in-hospital mortality (adjusted odds ratio [aOR], 0.83; P=0.02). ECMO with Impella versus ECMO only had similar in-hospital mortality (aOR, 1.09; P=0.695) but was associated with more bleeding (aOR, 1.21; P=0.007) and more acute kidney injury requiring hemodialysis (aOR, 1.42; P<0.001). ECMO with Impella versus ECMO with IABP was associated with greater risk of acute kidney injury requiring hemodialysis (aOR, 1.49; P=0.002), higher in-hospital mortality (aOR, 1.32; P=0.001), and higher 40-day mortality (hazard ratio, 1.25; P<0.001).

CONCLUSIONS

In patients with cardiogenic shock on VA-ECMO, LVU with Impella, particularly with 2.5/CP, was not associated with improved survival at 40 days but was associated with increased adverse events compared with IABP. More data are needed to assess Impella platform-specific comparative outcomes of LVU.

Trends in the Incidence of Cardiogenic Shock, and Utilization of Mechanical Circulatory Support in Myocarditis: Insights from the National Inpatient Sample 2016 to 2019

A subset of patients with myocarditis present with cardiogenic shock. There is a lack of contemporary data assessing the use of mechanical circulatory support (MCS) in these patients. Myocarditis hospitalizations were analyzed using the National Inpatient Sample between 2016 and 2019. Characteristics of patients with and without cardiogenic shock were assessed. Trends in mortality, MCS, right-sided cardiac catheterization (RHC) and endomyocardial biopsy were evaluated. The impact of RHC on consequent MCS and mortality was studied. A total of 38,300 hospitalizations for myocarditis were included in the study, of which 3,490 hospitalizations (9.1%) had cardiogenic shock. Patients with cardiogenic shock were older (p <0.001) and had more chronic kidney disease and atrial fibrillation. Between 2016 and 2019, there was an increase in myocarditis admissions but no difference in rates of cardiogenic shock and mortality and the use of extracorporeal membrane oxygenation, percutaneous ventricular assist devices, intra-aortic balloon pumps, left ventricular assist devices, and cardiac transplant. The most common form of MCS used in myocarditis was extracorporeal membrane oxygenation. The rates of RHC (p = 0.02) and endomyocardial biopsy (p = 0.03) increased over time. Patients who underwent RHC were more likely to receive mechanical support, and in patients with shock, RHC was associated with lower mortality (adjusted odds ratio 0.34, p <0.01). Myocarditis admissions increased over time but with no increase in the rates of cardiogenic shock and MCS. In patients with cardiogenic shock, RHC resulted in lower mortality.

Management of cardiac diseases in liver transplant recipients: Comprehensive review and multidisciplinary practice-based recommendations

Cardiac diseases are one of the most common causes of morbidity and mortality following liver transplantation (LT). Prior studies have shown that cardiac diseases affect close to one-third of liver transplant recipients (LTRs) long term and that their incidence has been on the rise. This rise is expected to continue as more patients with advanced age and/or non-alcoholic steatohepatitis undergo LT. In view of the increasing disease burden, a multidisciplinary initiative was developed to critically review the existing literature (between January 1, 1990 and March 17, 2021) surrounding epidemiology, risk assessment, and risk mitigation of coronary heart disease, arrhythmia, heart failure, and valvular heart disease and formulate practice-based recommendations accordingly. In this review, the expert panel emphasizes the importance of optimizing management of metabolic syndrome and its components in LTRs and highlights the cardioprotective potential for the newer diabetes medications (e.g., sodium glucose transporter-2 inhibitors) in this high-risk population. Tailoring the multidisciplinary management of cardiac diseases in LTRs to the cardiometabolic risk profile of the individual patient is critical. The review also outlines numerous knowledge gaps to pave the road for future research in this sphere with the ultimate goal of improving clinical outcomes.

Comprehensive echocardiographic evaluation of the right heart in patients with pulmonary vascular diseases: the PVDOMICS experience

AIMS

There is a wide spectrum of diseases associated with pulmonary hypertension, pulmonary vascular remodelling, and right ventricular dysfunction. The NIH-sponsored PVDOMICS network seeks to perform comprehensive clinical phenotyping and endophenotyping across these disorders to further evaluate and define pulmonary vascular disease.

METHODS AND RESULTS

Echocardiography represents the primary non-invasive method to phenotype cardiac anatomy, function, and haemodynamics in these complex patients. However, comprehensive right heart evaluation requires the use of multiple echocardiographic parameters and optimized techniques to ensure optimal image acquisition. The PVDOMICS echo protocol outlines the best practice approach to echo phenotypic assessment of the right heart/pulmonary artery unit.

CONCLUSION

Novel workflow processes, methods for quality control, data for feasibility of measurements, and reproducibility of right heart parameters derived from this study provide a benchmark frame of reference. Lessons learned from this protocol will serve as a best practice guide for echocardiographic image acquisition and analysis across the spectrum of right heart/pulmonary vascular disease.

Impact of hospital transfer to hubs on outcomes of cardiogenic shock in the real world

AIMS

Cardiogenic shock (CS) is associated with significant mortality, and there is a movement towards regional 'hub-and-spoke' triage systems to coordinate care and resources. Limited data exist on outcomes of patients treated at CS transfer hubs.

METHODS AND RESULTS

Cardiogenic shock hospitalizations were obtained from the Nationwide Readmissions Database 2010-2014. Centres receiving any interhospital transfers with CS in a given year were classified as CS transfer 'hubs'; those without transfers were classified as 'spokes.' In-hospital mortality was compared among three cohorts: (A) direct admissions to spokes, (B) direct admissions to hubs, and (C) interhospital transfer to hubs. Among hospitals treating CS, 70.6% were classified as spokes and 29.4% as hubs. A total of 130 656 (31.7%) hospitalizations with CS were direct admission to spokes, 253 234 (61.4%) were direct admissions to hubs, and 28 777 (7.0%) were transfer to hubs. CS mortality was 47.8% at spoke hospitals and was lower at hub hospitals, both for directly admitted (39.3%, P < 0.01) and transferred (33.4%, P < 0.01) patients. Hospitalizations at hubs had higher procedural frequency (including coronary artery bypass graft, right heart catheterization, mechanical circulatory support), greater length of stay, and greater costs. On multivariable analysis, direct admission to CS hubs [odds ratio (OR) 0.86, 95% confidence interval (CI) 0.84-0.89, P < 0.01] and transfer to hubs (OR 0.72, 95% CI 0.69-0.76, P < 0.01) were both associated with lower mortality.

CONCLUSION

While acknowledging the limited ability of the Nationwide Readmissions Database to classify CS severity on presentation, treatment of CS at transfer hubs was associated with significantly lower mortality within this large real-world sample.

Outcomes of Hospitalizations for Cardiogenic Shock at Left Ventricular Assist Device Versus Non-Left Ventricular Assist Device Centers

Background Cardiogenic shock (CS) is a complex syndrome associated with high morbidity and mortality. In recent years, many US hospitals have formed multidisciplinary shock teams capable of rapid diagnosis and triage. Because of preexisting collaborative systems of care, hospitals with left ventricular assist device (LVAD) programs may also represent "centers of excellence" for CS care. However, the outcomes of patients with CS at LVAD centers have not been previously evaluated. Methods and Results Patients with CS were identified in the 2012 to 2014 National Inpatient Sample. Clinical characteristics, revascularization rates, and use of mechanical circulatory support were analyzed in LVAD versus non-LVAD centers. The association between hospital type and in-hospital mortality was examined using multivariable logistic regression models. Of 272 075 hospitalizations, 26.0% were in LVAD centers. CS attributable to causes other than acute myocardial infarction represented most cases. In-hospital mortality was lower in LVAD centers (38.9% versus 43.3%; P<0.001). In multivariable analysis, the odds of mortality remained significantly lower for hospitalizations in LVAD centers (odds ratio, 0.89; P<0.001). In patients with CS secondary to acute myocardial infarction, revascularization rates were similar between LVAD and non-LVAD centers. The use of intra-aortic balloon pump (18.7% versus 18.8%) and Impella/TandemHeart (2.6% versus 1.9%) was similar between hospital types, whereas extracorporeal membrane oxygenation was used more frequently in LVAD centers (4.3% versus 0.2%; P<0.001). Conclusions Risk-adjusted mortality was lower in patients with CS who were hospitalized at LVAD centers. These centers likely represent specialized, shock team capable institutions across the country that may be best suited to manage patients with CS.

A Perspective from New York of COVID 19: Effect and impact on cardiac surgery

BACKGROUND AND AIM

First reported in December of 2019, the COVID-19 pandemic caused by SARS-CoV-2 has had a profound impact on the implementation of care. Here, we describe our institutional experience with a rapid influx of patients at the epicenter of the pandemic.

METHODS

We retrospectively review our experience with the departments of cardiology, cardiothoracic surgery, anesthesia, and critical care medicine and summarize protocols developed in the midst of the pandemic.

RESULTS

The rapid influx of patients requiring an intensive level of care required a complete restructuring of units, including the establishment of a new COVID-19 negative unit for the care of patients requiring urgent or emergent non-COVID-19 related care including open-heart surgery. This unique unit allowed for the delivery of safe and effective care in the epicenter of the pandemic.

CONCLUSIONS

Here, we demonstrate the response of a large tertiary academic medical center to the COVID-19 pandemic. Specifically, we demonstrate how rapid structural changes can allow for the continued delivery of cardiac surgical care with similar outcomes as those reported before the pandemic.

Hospital Preparedness for COVID-19: A Practical Guide from a Critical Care Perspective

In response to the estimated potential impact of coronavirus disease (COVID-19) on New York City hospitals, our institution prepared for an influx of critically ill patients. Multiple areas of surge planning progressed, simultaneously focused on infection control, clinical operational challenges, ICU surge capacity, staffing, ethics, and maintenance of staff wellness. The protocols developed focused on clinical decisions regarding intubation, the use of high-flow oxygen, engagement with infectious disease consultants, and cardiac arrest. Mechanisms to increase bed capacity and increase efficiency in ICUs by outsourcing procedures were implemented. Novel uses of technology to minimize staff exposure to COVID-19 as well as to facilitate family engagement and end-of-life discussions were encouraged. Education and communication remained key in our attempts to standardize care, stay apprised on emerging data, and review seminal literature on respiratory failure. Challenges were encountered and overcome through interdisciplinary collaboration and iterative surge planning as ICU admissions rose. Support was provided for both clinical and nonclinical staff affected by the profound impact COVID-19 had on our city. We describe in granular detail the procedures and processes that were developed during a 1-month period while surge planning was ongoing and the need for ICU capacity rose exponentially. The approaches described here provide a potential roadmap for centers that must rapidly adapt to the tremendous challenge posed by this and potential future pandemics.

Association Between Heart Transplantation and Subsequent Risk of Stroke Among Patients With Heart Failure

Background and Purpose- It is uncertain whether heart transplantation decreases the risk of stroke. The objective of our study was to determine whether heart transplantation is associated with a decreased risk of subsequent stroke among patients with heart failure awaiting transplantation. Methods- We performed a retrospective cohort study using administrative data from New York, California, and Florida between 2005 and 2015. Individuals with heart failure awaiting heart transplantation were identified using previously validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes for heart failure in combination with code V49.83 for awaiting organ transplant status. Individuals with prior stroke were excluded. Our primary exposure variable was heart transplantation, modeled as a time-varying covariate and defined by procedure code 37.51. The primary outcome was stroke, defined as the composite of ischemic and hemorrhagic stroke. Survival statistics were used to calculate stroke incidence, and Cox proportional hazards analysis was used to determine the association between heart transplantation and stroke while adjusting for demographics, stroke risk factors, Elixhauser comorbidities, and implantation of a left ventricular assist device. Results- We identified 7848 patients with heart failure awaiting heart transplantation, of whom 1068 (13.6%) underwent heart transplantation. During a mean follow-up of 2.7 years, we identified 428 strokes. The annual incidence of stroke was 0.7% (95% CI, 0.5%-1.0%) after heart transplantation versus 2.4% (95% CI, 2.2%-2.6%) among those awaiting heart transplantation. After adjustment for potential confounders, heart transplantation was associated with a lower risk of stroke (hazard ratio, 0.4; 95% CI, 0.2-0.6). Conclusions- Heart transplantation is associated with a decreased risk of stroke among patients with heart failure awaiting transplantation.

Clinical and Socioeconomic Predictors of Heart Failure Readmissions: A Review of Contemporary Literature

Heart failure represents a clinical syndrome that results from a constellation of disease processes affecting myocardial function. Although recent studies have suggested a declining or stable incidence of heart failure, patients with heart failure continue to have high hospitalization and readmission rates, resulting in a substantial economic and public health burden. We searched PubMed and Google Scholar to identify published literature from 1998 through 2018 using the following keywords: heart failure, readmissions, predictors, prediction models, and interventions. Cited references were also used to identify relevant literature. Developments in the diagnosis and management of patients with heart failure have improved hospitalization and readmission rates in the past few decades. However, heart failure remains the most common cause of hospitalization in persons older than 65 years. As a result, given the enormous clinical and financial burden associated with heart failure readmissions on health care, there has been growing interest in the investigation of mechanisms aimed at improving outcomes and curtailing associated costs of care. Herein, we review the current literature on clinical and socioeconomic predictors of heart failure readmissions, briefly discussing limitations of existing strategies and providing an overview of current technology aimed at reducing hospitalizations.

Contribution of the left atrial remodeling to the elevated pulmonary capillary wedge pressure in patients with WHO Group II pulmonary hypertension

BACKGROUND

The contribution of progressive left atrial (LA) enlargement to elevated pulmonary capillary wedge pressure (PCWP) in patients with WHO Group II pulmonary hypertension (PH) has not been well studied. We hypothesized that progressive LA enlargement is associated with increased PCWP.

METHODS

A cross-sectional retrospective cohort consisted of 166 patients with HF and WHO Group II PH, confirmed by right heart catheterization (RHC). LA anteroposterior dimension and volume were measured on TTE. PCWP and other hemodynamic parameters were measured by RHC. Univariate and multivariate logistic regression models were used for analysis.

RESULTS

LA enlargement was associated with advanced age, increased BMI, and LV ejection fraction < 40%. PCWP was progressively increased in patients with dilated LA: 16.9 ± 7.4 mmHg in normal LA, 17.6 ± 7.2 mmHg in mildly dilated LA, 22.6 ± 6.3 mmHg in moderately and 22 ± 7.6 in severely dilated LA (p < 0.001). In multiple logistic regression, after adjustment for echocardiographic and clinical variables, severe LA enlargement was independently predictive of elevated PCWP (OR 3.468; 95% CI 1.046-11.504; p = 0.042). After excluding significant mitral regurgitation, progressive LA dilatation was associated with higher PCWP V-wave amplitude: from 21.3 ± 10.4 mmHg in patients with normal LA size, to 30.9 ± 11.7 mmHg in moderately dilated and 31.0 ± 11.6 mmHg in severely dilated LA (p < 0.001).

CONCLUSIONS

In patients with HF and WHO Group II PH, progressive LA enlargement was independently associated with elevated PCWP. After excluding significant mitral regurgitation, LA enlargement was also associated with increased V-wave amplitude, indicative of decreased atrial compliance.

Sex- and Race-Related Differences in Characteristics and Outcomes of Hospitalizations for Heart Failure With Preserved Ejection Fraction

Background

Sex and race have emerged as important contributors to the phenotypic heterogeneity of heart failure with preserved ejection fraction (HFpEF). However, there remains a need to identify important sex‐ and race‐related differences in characteristics and outcomes using a nationally representative cohort.

Methods and Results

Data were obtained from the Agency for Healthcare Research and Quality Healthcare Cost and Utilization Project—Nationwide Inpatient Sample files between 2008 and 2012. Hospitalizations with a diagnosis of HFpEF were included for analysis. Demographics, hospital characteristics, and age‐adjusted comorbidity prevalence rates were compared between men and women and whites and blacks. In‐hospital mortality was determined and compared for each subgroup. Multivariable regression analyses were used to identify and compare correlates of in‐hospital mortality for each subgroup. A sample of 1 889 608 hospitalizations was analyzed. Men with HFpEF were slightly younger than women with HFpEF and had a higher Elixhauser comorbidity score. Men experienced higher in‐hospital mortality compared with women, a finding that was attenuated after adjusting for comorbidity. Blacks with HFpEF were younger than whites with HFpEF, with lower rates of most comorbidities. Hypertension, diabetes, anemia, and chronic renal failure were more common among blacks. Blacks experienced lower in‐hospital mortality compared with whites, even after adjusting for age and comorbidity. Important correlates of mortality among all 4 subgroups included pulmonary circulation disorders, liver disease, and chronic renal failure. Atrial fibrillation was an important correlate of mortality only among women and blacks.

Conclusions

Differences in patient characteristics and outcomes reinforce the notion that sex and race contribute to the phenotypic heterogeneity of HFpEF.

Stroke Risk and Mortality in Patients With Ventricular Assist Devices

BACKGROUND AND PURPOSE

Ventricular assist devices (VADs) have advanced the management of end-stage heart failure. However, these devices are associated with hemorrhagic and thrombotic complications, including stroke. We assessed the incidence, risk factors, and outcomes of ischemic and hemorrhagic stroke after VAD placement.

METHODS

Using administrative claims data from acute care hospitals in California, Florida, and New York from 2005 to 2013, we identified patients who underwent VAD placement, defined by the International Classification of Diseases, Ninth Revision, Clinical Modification code 37.66. Ischemic and hemorrhagic strokes were identified by previously validated coding algorithms. We used survival statistics to determine the incidence rates and Cox proportional hazard analyses to examine the associations.

RESULTS

Among 1813 patients, we identified 201 ischemic strokes and 116 hemorrhagic strokes during 3.4 (±2.0) years of follow-up after implantation of a VAD. The incidence of stroke was 8.7% per year (95% confidence interval [CI], 7.7-9.7). The annual incidence of ischemic stroke (5.5%; 95% CI, 4.8-6.4) was nearly double that of hemorrhagic stroke (3.1%; 95% CI, 2.6-3.8). Women faced a higher hazard of stroke than men (hazard ratio, 1.6; 95% CI, 1.2-2.1), particularly hemorrhagic stroke (hazard ratio, 2.2; 95% CI, 1.4-3.4). Stroke was strongly associated with subsequent in-hospital mortality (hazard ratio, 6.1; 95% CI, 4.6-7.9).

CONCLUSIONS

The incidence of stroke after VAD implantation was 8.7% per year, and incident stroke was strongly associated with subsequent in-hospital mortality. Notably, ischemic stroke occurred at nearly twice the rate of hemorrhagic stroke. Women seemed to face a higher risk for hemorrhagic stroke than men.

Measures of Body Size and Composition and Risk of Incident Atrial Fibrillation in Older People: The Cardiovascular Health Study

Various anthropometric measures, including height, have been associated with atrial fibrillation (AF). This raises questions about the appropriateness of using ratio measures such as body mass index (BMI), which contains height squared in its denominator, in the evaluation of AF risk. Among older adults, the optimal anthropometric approach to risk stratification of AF remains uncertain. Anthropometric and bioelectrical impedance measures were obtained from 4,276 participants (mean age = 72.4 years) free of cardiovascular disease in the Cardiovascular Health Study. During follow-up (1989-2008), 1,050 cases of AF occurred. BMI showed a U-shaped association, whereas height, weight, waist circumference, hip circumference, fat mass, and fat-free mass were linearly related to incident AF. The strongest adjusted association occurred for height (per each 1-standard-deviation increment, hazard ratio = 1.38, 95% confidence interval: 1.25, 1.51), which exceeded all other measures, including weight (hazard ratio = 1.21, 95% confidence interval: 1.13, 1.29). Combined assessment of log-transformed weight and height showed regression coefficients that departed from the 1 to -2 ratio inherent in BMI, indicating a loss of predictive information. Risk estimates for AF tended to be stronger for hip circumference than for waist circumference and for fat-free mass than for fat mass, which was explained largely by height. These findings highlight the prominent role of body size and the inadequacy of BMI as determinants of AF in older adults.

Characteristics of Hospitalizations for Heart Failure with Preserved Ejection Fraction

BACKGROUND

Hospitalizations for heart failure with preserved ejection fraction (HFpEF) are increasing. There are limited data examining national trends in patients hospitalized with HFpEF.

METHODS

Using the Nationwide Inpatient Sample, we examined 5,046,879 hospitalizations with a diagnosis of acute heart failure in 2003-2012, stratifying hospitalizations by HFpEF and heart failure with reduced ejection fraction (HFrEF). Patient and hospital characteristics, in-hospital mortality, and length of stay were examined.

RESULTS

Compared with HFrEF, those with HFpEF were older, more commonly female, and more likely to have hypertension, atrial fibrillation, chronic lung disease, chronic renal failure, and anemia. Over time, HFpEF comprised increasing proportions of men and patients aged ≥75 years. In-hospital mortality rate for HFpEF decreased by 13%, largely due to improved survival in those aged ≥65 years. Multivariable regression analyses showed that pulmonary circulation disorders, liver disease, and chronic renal failure were independent predictors of in-hospital mortality, whereas treatable diseases including hypertension, coronary artery disease, and diabetes were inversely associated.

CONCLUSIONS

This study represents the largest cohort of patients hospitalized with HFpEF to date, yielding the following observations: number of hospitalizations for HFpEF was comparable with that of HFrEF; patients with HFpEF were most often women and elderly, with a high burden of comorbidities; outcomes appeared improved among a subset of patients; pulmonary hypertension, liver disease, and chronic renal failure were strongly associated with poor outcomes.

Abstract WP194: Stroke Risk and Mortality in Patients with Ventricular Assist Devices

Background: Ventricular assist devices (VADs) have revolutionized the management of end-stage heart failure. However, these devices are associated with many complications, including stroke.

Hypothesis: We sought to determine the risk and risk factors for stroke after VAD placement and to assess the hypothesis that stroke is associated with increased mortality after VAD placement.

Methods: From administrative claims data on all discharges from nonfederal acute care hospitals in California, Florida, and New York from 2005-2012, we used International Classification of Diseases, 9 th Revision, Clinical Modification ( ICD-9-CM ) code 37.66 to identify patients who underwent VAD placement. Patients were included regardless of whether they underwent VAD placement as destination therapy or as bridge to transplant. Ischemic and hemorrhagic strokes were identified by validated coding algorithms. Kaplan-Meier statistics were used to calculate cumulative rates. Cox proportional hazard analyses were used to identify risk factors for stroke in patients with VADs and to evaluate the association between stroke (modeled as a time-varying covariate) and mortality.

Results: We had 3.0 (±1.7) years of follow-up data on 1,398 patients after implantation of a VAD. The mean age of the patients was 55.4 years (±13.2), and patients were predominantly male. A total of 227 strokes were identified: 147 ischemic and 79 hemorrhagic. The cumulative stroke rate was 24.3% (95% confidence interval [CI], 21.3-27.7%). After adjustment for age, race, insurance status, and comorbidities, women had a higher hazard of stroke than men (hazard ratio [HR], 1.7; 95% CI, 1.2-2.3), particularly hemorrhagic stroke (HR, 2.6; 95% CI, 1.5-4.3). Stroke was strongly associated with subsequent mortality (HR, 4.1; 95% CI, 3.3-5.1).

Conclusion: Stroke is common in patients after VAD placement and is strongly associated with mortality in this vulnerable population. Women appear to be at higher stroke risk than men, particularly for hemorrhagic stroke.

Pulmonary tumour thrombotic microangiopathy as a cause of new-onset pulmonary hypertension in a patient with metastatic low-grade serous ovarian cancer

A 78-year-old woman with metastatic low-grade serous ovarian cancer presented with rapidly progressive exertional dyspnoea and hypoxia, and was found to have new-onset severe pulmonary hypertension (PH) by right heart catheterisation. A diagnosis of pulmonary tumour thrombotic microangiopathy (PTTM) was made at autopsy. PTTM is a rare complication of advanced cancer that often presents as rapidly progressive PH or acute hypoxic respiratory failure. Widespread tumour cell emboli in the pulmonary arteries and arterioles are hypothesised to induce fibrocellular subintimal proliferation and microthrombi, leading to increased pulmonary vascular resistance and PH. PTTM arising from serous ovarian cancer is exceedingly rare, with only two previously reported cases. A discussion of the pathophysiology, diagnosis and management of PTTM is presented.

The impact of height on the risk of atrial fibrillation: the Cardiovascular Health Study

AIMS

Atrial fibrillation (AF) is the most common sustained arrhythmia. Increased body size has been associated with AF, but the relationship is not well understood. In this study, we examined the effect of increased height on the risk of AF and explore potential mediators and implications for clinical practice.

METHODS AND RESULTS

We examined data from 5860 individuals taking part in the Cardiovascular Health Study, a cohort study of older US adults followed for a median of 13.6 (women) and 10.3 years (men). Multivariate linear models and age-stratified Cox proportional hazards and risk models were used, with focus on the effect of height on both prevalent and incident AF. Among 684 (22.6%) and 568 (27.1%) incident cases in women and men, respectively, greater height was significantly associated with AF risk [hazard ratio (HR)(women) per 10 cm 1.32, confidence interval (CI) 1.16-1.50, P < 0.0001; HR(men) per 10 cm 1.26, CI 1.11-1.44, P < 0.0001]. The association was such that the incremental risk from sex was completely attenuated by the inclusion of height (for men, HR 1.48, CI 1.32-1.65, without height, and HR 0.94, CI 0.85-1.20, with height included). Inclusion of height in the Framingham model for incident AF improved discrimination. In sequential models, however, we found minimal attenuation of the risk estimates for AF with adjustment for left ventricular (LV) mass and left atrial (LA) dimension. The associations of LA and LV size measurements with AF risk were weakened when indexed to height.

CONCLUSION

Independent from sex, increased height is significantly associated with the risk of AF.

Incremental value of biochemical and echocardiographic measures in prediction of ischemic stroke: the Strong Heart Study

BACKGROUND AND PURPOSE

American Indians have high rates of stroke. Improved risk stratification could enhance prevention, but the ability of biochemical and echocardiographic markers of preclinical disease to improve stroke prediction is not well-defined.

METHODS

We evaluated such markers as predictors of ischemic stroke in a community-based cohort of American Indians without prevalent cardiovascular or renal disease. Laboratory markers included C-reactive protein, fibrinogen, urine albumin-to-creatinine ratio, and glycohemoglobin (HbA1c), whereas echocardiographic parameters comprised left atrial diameter, left ventricular mass, mitral annular calcification, and the ratio of early to late mitral diastolic velocities. Predictive performance was judged by indices of discrimination, reclassification, and calibration.

RESULTS

After adjustment for standard risk factors, only HbA1c, albuminuria, and left atrial diameter were significantly associated with first ischemic stroke. Addition of HbA1c, although not urine albumin-to-creatinine ratio, to a basic clinical model significantly improved the C-statistic (0.714 versus 0.695; P=0.044), whereas left atrial diameter modestly enhanced integrated discrimination improvement (0.90%; P=0.004), but not the C-statistic (0.701; P=0.528). When combined with HbA1c, left atrial diameter further increased integrated discrimination improvement (1.81%; P<0.001) but not the C-statistic (0.716). No marker achieved significant net reclassification improvement.

CONCLUSIONS

In this cohort at high cardiometabolic risk, HbA1c emerged as the foremost predictor of ischemic stroke when added to traditional risk factors, affording substantially improved discrimination, with a more modest contribution for left atrial diameter. These findings bolster the role of HbA1c in cardiovascular risk assessment among persons with glycometabolic disorders and provide impetus for further study of the incremental value of echocardiography in high-risk populations.

Relation between mitral annular calcium and complex aortic atheroma in patients with cerebral ischemia referred for transesophageal echocardiography

Mitral annular calcium (MAC) has been shown to be an independent predictor of stroke, but the basis for this association remains incompletely defined. This study was conducted to investigate the extent to which aortogenic embolism may mediate the MAC-stroke relation. In a cross-sectional study of patients referred for transesophageal echocardiography for the evaluation of cerebral ischemia, the relation between MAC and proximal and distal complex aortic atheroma (CAA) was assessed. In 419 patients composing the study cohort, MAC was associated with atherosclerosis risk factors, previous cardiovascular disease, atrial fibrillation, ipsilateral large-artery stenosis, left-sided cardiac abnormalities, and aortic valve calcium. MAC was associated with CAA of the proximal and distal thoracic aorta in unadjusted analyses, and these associations became stronger with increasing MAC severity. After adjustment for clinical and echocardiographic covariates, MAC exhibited a significant association with proximal and distal CAA in the entire cohort. In patients without alternative potential mechanisms for cerebral ischemia, however, the relation with proximal CAA became more pronounced (adjusted odds ratio 2.74, 95% confidence interval 1.22 to 6.16), but that for distal CAA changed little and became nonsignificant (adjusted odds ratio 1.97, 95% confidence interval 0.87 to 4.45). In conclusion, MAC was significantly associated with proximal and distal CAA independent of clinical and echocardiographic covariates in this cohort with cerebral ischemia, but in subjects without identifiable alternative mechanisms, the magnitude of the relation increased only for proximal CAA. These findings support the role of proximal CAA as a direct mediator of the increased stroke risk associated with MAC.

Yield of transesophageal echocardiography for nonbacterial thrombotic endocarditis and other cardiac sources of embolism in cancer patients with cerebral ischemia

Cerebrovascular events occur frequently in patients who succumb to cancer, and nonbacterial thrombotic endocarditis (NBTE) is a frequent postmortem finding in these patients. Despite the excellent diagnostic accuracy of transesophageal echocardiography (TEE) for cardiac sources of cerebral embolism, however, the prevalence of NBTE and other cardioembolic sources in patients with cancer and cerebral ischemia has not been investigated using this modality. This study examined the frequency of cardioembolic findings in consecutive patients with cancer referred to our institution for TEE evaluation of cerebrovascular events. The study cohort comprised 51 patients, of whom 18% had marantic vegetations, and 47% and 55% of whom had definite and definite or probable cardiac sources of embolism, respectively. The present study documents, for the first time, a high frequency of marantic endocarditis and other cardioembolic sources in patients with cancer and cerebrovascular events selected for TEE. This finding has important implications for evaluation and management in this patient population.