Proteomic Signature of HIV-Associated Subclinical Left Atrial Remodeling and Incident Heart Failure.

Background: People living with HIV (PLWH) are at higher risk of heart failure (HF) and preceding subclinical cardiac abnormalities, including left atrial dilation, compared to people without HIV (PWOH). Hypothesized mechanisms include premature aging linked to chronic immune activation. We leveraged plasma proteomics to identify potential novel contributors to HIV-associated differences in indexed left atrial volume (LAVi) among PLWH and PWOH and externally validated identified proteomic signatures with incident HF among a cohort of older PWOH. Methods: We performed proteomics (Olink Explore 3072) on plasma obtained concurrently with cardiac magnetic resonance imaging among PLWH and PWOH in the United States. Proteins were analyzed individually and as agnostically defined clusters. Cross-sectional associations with HIV and LAVi were estimated using multivariable regression with robust variance. Among an independent general population cohort, we estimated associations between identified signatures and LAVi using linear regression and incident HF using Cox regression. Results: Among 352 participants (age 55±6 years; 25% female), 61% were PLWH (88% on ART; 73% with undetectable HIV RNA) and mean LAVi was 29±9 mL/m 2 . Of 2594 analyzed proteins, 439 were associated with HIV serostatus, independent of demographics, hepatitis C virus infection, renal function, and substance use (FDR<0.05). We identified 73 of these proteins as candidate contributors to the independent association between positive HIV serostatus and higher LAVi, enriched in tumor necrosis factor (TNF) signaling and immune checkpoint proteins regulating T cell, B cell, and NK cell activation. We identified one protein cluster associated with LAVi and HIV regardless of HIV viral suppression status, which comprised 42 proteins enriched in TNF signaling, ephrin signaling, and extracellular matrix (ECM) organization. This protein cluster and 30 of 73 individual proteins were associated with incident HF among 2273 older PWOH (age 68±9 years; 52% female; 8.5±1.4 years of follow-up). Conclusion: Proteomic signatures that may contribute to HIV-associated LA remodeling were enriched in immune checkpoint proteins, cytokine signaling, and ECM organization. These signatures were also associated with incident HF among older PWOH, suggesting specific markers of chronic immune activation, systemic inflammation, and fibrosis may identify shared pathways in HIV and aging that contribute to risk of HF.

Association of HIV infection with clinical features and outcomes of patients with aortic aneurysms.

Data on the characteristics and outcomes of hospitalized patients with aortic aneurysms (AA) and HIV remain scarce. This is a cohort study of hospitalized adult patients with a diagnosis of AA from 2013 to 2019 using the US National Inpatient Readmission Database. Patients with a diagnosis of HIV were identified. Our outcomes included trends in hospitalizations and comparison of clinical characteristics, complications, and mortality in patients with AA and HIV compared to those without HIV. Among 1,905,837 hospitalized patients with AA, 4416 (0.23%) were living with HIV. There was an overall age-adjusted increase in the rate of HIV among patients hospitalized with AA over the years (14-29 per 10,000 person-years; age-adjusted p-trend < 0.001). Patients with AA and HIV were younger than those without HIV (median age: 60 vs 76 years, p < 0.001) and were less likely to have a history of smoking, hypertension, dyslipidemia, diabetes mellitus, and obesity. Thoracic aortic aneurysms were more prevalent in those with HIV (37.5% vs 26.7%, p < 0.001). On multivariable logistic regression, HIV was not associated with increased risk of aortic rupture (OR: 0.79; 95% CI: 0.61-1.01, p = 0.06), acute aortic dissection (OR: 0.73; 95% CI: 0.51-1.06, p = 0.3), readmissions (OR: 1.04; 95% CI: 0.95-1.13, p = 0.4), or aortic repair (OR: 0.89; 95% CI: 0.79-1.00, p = 0.05). Hospitalized patients with AA and HIV had a lower crude mortality rate compared to those without HIV (OR: 0.75 (0.63-0.91), p = 0.003). Hospitalized patients with AA and HIV likely constitute a distinct group of patients with AA; they are younger, have fewer traditional cardiovascular risk factors, and a higher rate of thoracic aorta involvement. Differences in clinical features may account for the lower mortality rate observed in patients with AA and HIV compared to those without HIV.

Longitudinal Prediction of Ventricular Arrhythmic Risk in Patients With Arrhythmogenic Right Ventricular Cardiomyopathy.

BACKGROUND: The arrhythmogenic right ventricular cardiomyopathy (ARVC) risk calculator stratifies risk for incident sustained ventricular arrhythmias (VA) at the time of ARVC diagnosis. However, included risk factors change over time, and how well the ARVC risk calculator performs at follow-up is unknown. METHODS: This was a retrospective analysis of patients with definite ARVC and without prior sustained VA. Risk factors for VA including age, nonsustained ventricular tachycardia, premature ventricular complex burden, T-wave inversions on electrocardiogram, cardiac syncope, right ventricular function, therapeutic medication use, and exercise intensity were assessed at the time of 2010 Task Force Criteria based ARVC diagnosis and upon repeat evaluations. Changes in these risk factors were analyzed over 5-year follow-up. The 5-year risk of VA was predicted longitudinally using (1) the baseline ARVC risk calculator prediction, (2) the ARVC risk prediction calculated using updated risk factors, and (3) time-varying Cox regression. Discrimination and calibration were assessed in comparison to observed VA event rates. RESULTS: Four hundred eight patients with ARVC experiencing 132 primary VA events were included. Matched comparison of risk factors at baseline versus at 5 years of follow-up revealed decreased burdens of premature ventricular complexes (-1200/day) and nonsustained ventricular tachycardia (-14%). Presence of significant right ventricular dysfunction and number of T-wave inversions on electrocardiogram were unchanged. Observed risk for VA decreased by 13% by 5 years follow-up. The baseline ARVC risk calculator's ability to predict 5-year VA risk worsened during follow-up (C statistics, 0.83 at diagnosis versus 0.68 at 5 years). Both the updated ARVC risk calculator (C statistics of 0.77) and time-varying Cox regression model (C statistics, 0.77) had strong discrimination. The updated ARVC risk calculator overestimated 5-year VA risk by an average of +6%. CONCLUSIONS: Risk factors for VA in ARVC are dynamic, and overall risk for incident sustained VA decreases during follow-up. Up-to-date risk factor assessment improves VA risk stratification.

Circulating biomarker correlates of left atrial size and myocardial extracellular volume fraction among persons living with and without HIV.

BACKGROUND: Infection with human immunodeficiency virus (HIV) is associated with higher risk for myocardial disease despite modern combination antiretroviral therapy (cART). Factors contributing to this excess risk, however, remain poorly characterized. We aimed to assess cross-sectional relationships between elevations of left atrial volume index (LAVI) and myocardial extracellular volume (ECV) fraction that have been reported in persons living with HIV and levels of circulating biomarkers of inflammation, fibrosis, and myocyte stretch among persons living with and without HIV (PLWH, PLWOH). METHODS: Participants from three cohorts of PLWH and PLWOH underwent cardiovascular magnetic resonance imaging for measurement of LAVI and ECV. Levels of circulating proteins (IL-6, sCD14, galectin-3, NT-proBNP, GDF-15, TIMP-2, MMP-2, and hsTnI) were measured using immunoassays. Associations were assessed using logistic and linear regression, adjusting for demographics, substance use, and clinical characteristics. RESULTS: Among 381 participants with and without HIV, median age (IQR) was 55.1 (51.2, 58.4) years, 28% were female, 69% were Black, and 46% were current smokers. Sixty-two percent were PLWH (n = 235), of whom 88% were receiving cART and 72% were virally suppressed. PLWH had higher levels of sCD14 (p = < 0.001), GDF-15 (p = < 0.001), and NT-proBNP (p = 0.03) compared to PLWOH, while levels of other biomarkers did not differ by HIV serostatus, including IL-6 (p = 0.84). Among PLWH, higher sCD14, GDF-15, and NT-proBNP were also associated with lower CD4 + cell count, and higher NT-proBNP was associated with detectable HIV viral load. NT-proBNP was associated with elevated LAVI (OR: 1.79 [95% CI: 1.31, 2.44]; p < 0.001) with no evidence of effect measure modification by HIV serostatus. Other associations between HIV-associated biomarkers and LAVI or ECV were small or imprecise. CONCLUSIONS: Our findings suggest that elevated levels of sCD14, GDF-15, and NT-proBNP among PLWH compared to PLWOH observed in the current cART era may only minimally reflect HIV-associated elevations in LAVI and ECV. Future studies of excess risk of myocardial disease among contemporary cohorts of PLWH should investigate mechanisms other than those connoted by the studied biomarkers.

Myocardial ATP depletion detected noninvasively predicts sudden cardiac death risk in patients with heart failure.

BACKGROUNDSudden cardiac death (SCD) remains a worldwide public health problem in need of better noninvasive predictive tools. Current guidelines for primary preventive SCD therapies, such as implantable cardioverter defibrillators (ICDs), are based on left ventricular ejection fraction (LVEF), but these guidelines are imprecise: fewer than 5% of ICDs deliver lifesaving therapy per year. Impaired cardiac metabolism and ATP depletion cause arrhythmias in experimental models, but to our knowledge a link between arrhythmias and cardiac energetic abnormalities in people has not been explored, nor has the potential for metabolically predicting clinical SCD risk.METHODSWe prospectively measured myocardial energy metabolism noninvasively with phosphorus magnetic resonance spectroscopy in patients with no history of significant arrhythmias prior to scheduled ICD implantation for primary prevention in the setting of reduced LVEF (≤35%).RESULTSBy 2 different analyses, low myocardial ATP significantly predicted the composite of subsequent appropriate ICD firings for life-threatening arrhythmias and cardiac death over approximately 10 years. Life-threatening arrhythmia risk was approximately 3-fold higher in patients with low ATP and independent of established risk factors, including LVEF. In patients with normal ATP, rates of appropriate ICD firings were several-fold lower than reported rates of ICD complications and inappropriate firings.CONCLUSIONTo the best of our knowledge, these are the first data linking in vivo myocardial ATP depletion and subsequent significant arrhythmic events in people, suggesting an energetic component to clinical life-threatening ventricular arrhythmogenesis. The findings support investigation of metabolic strategies that limit ATP loss to treat or prevent life-threatening cardiac arrhythmias and herald noninvasive metabolic imaging as a complementary SCD risk stratification tool.TRIAL REGISTRATIONClinicalTrials.gov NCT00181233.FUNDINGThis work was supported by the DW Reynolds Foundation, the NIH (grants HL61912, HL056882, HL103812, HL132181, HL140034), and Russell H. Morgan and Clarence Doodeman endowments at Johns Hopkins.

Multimodality Evaluation of Aortic Insufficiency and Aortitis in Rheumatologic Diseases.

Aortic insufficiency is commonly observed in rheumatologic diseases such as ankylosing spondylitis, systemic lupus erythematosus, antiphospholipid syndrome, Behçet's disease, granulomatosis with polyangiitis, and Takayasu arteritis. Aortic insufficiency with an underlying rheumatologic disease may be caused by a primary valve pathology (leaflet destruction, prolapse or restriction), annular dilatation due to associated aortitis or a combination of both. Early recognition of characteristic valve and aorta morphology on cardiac imaging has both diagnostic and prognostic importance. Currently, echocardiography remains the primary diagnostic tool for aortic insufficiency. Complementary use of computed tomography, cardiac magnetic resonance imaging and positron emission tomography in these systemic conditions may augment the assessment of underlying mechanism, disease severity and identification of relevant non-valvular/extracardiac pathology. We aim to review common rheumatologic diseases associated with aortic insufficiency and describe their imaging findings that have been reported in the literature.

Association of HIV Serostatus and Inflammation With Ascending Aortic Size.

Background The prevalence and extent of subclinical large vessel vasculopathy is not well defined among people living with HIV. We aimed to evaluate associations between aortic root and ascending aortic sizes measured by 2-dimensional transthoracic echocardiography and HIV serostatus, and to identify risk factors for larger aortic sizes among men with HIV, including levels of circulating inflammatory markers. Methods and Results Using clinical and echocardiographic data from the MACS (Multicenter AIDS Cohort Study), adjusted multivariable linear and logistic regression was performed. Four segments of the proximal aorta were measured: aortic annulus, aortic root at the sinuses of Valsalva, sinotubular junction, and ascending aorta. HIV infection was associated with significantly larger aortic root (0.03 cm [95% CI, 0.002-0.06 cm]) and ascending aorta (0.04 cm [95% CI, 0.01-0.06 cm]) diameters. Higher standardized nadir CD4 (cluster of differentiation 4) T-cell count was significantly associated with smaller aortic root (-0.03 cm [95% CI, -0.05 to -0.01 cm]), sinotubular junction (-0.03 cm [95% CI, -0.05 to -0.01 cm]), and ascending aorta (-0.03 cm [95% CI, -0.05 to -0.004 cm]) diameters. Higher levels of standardized TNF-α (tumor necrosis factor-α) were associated with larger diameters of the aortic annulus (0.02 cm [95% CI, 0.003-0.04 cm]) and sinotubular junction (0.02 cm [95% CI, 0.002-0.04 cm]). There were no other cardiovascular or HIV disease severity-related risk factors associated with the aortic dimensions. Conclusions HIV infection is an independent risk factor for greater ascending aortic sizes. Lower nadir CD4 T-cell count and higher TNF-α levels are associated with larger aortic sizes in men with HIV. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00046280.

Multimodality Imaging in Arrhythmogenic Right Ventricular Cardiomyopathy.

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare, heritable myocardial disease associated with the development of ventricular arrhythmias, heart failure, and sudden cardiac death in early adulthood. Multimodality imaging is a central component in the diagnosis and evaluation of ARVC. Diagnostic criteria established by an international task force in 2010 include noninvasive parameters from echocardiography and cardiac magnetic resonance imaging. These criteria identify right ventricular structural abnormalities, chamber and outflow tract dilation, and reduced right ventricular function as features of ARVC. Echocardiography is a widely available and cost-effective technique, and it is often selected for initial evaluation. Beyond fulfillment of diagnostic criteria, features such as abnormal tricuspid annular plane excursion, increased right ventricular basal diameter, and abnormal strain patterns have been described. 3-dimensional echocardiography may also expand opportunities for structural and functional assessment of ARVC. Cardiac magnetic resonance has the ability to assess morphological and functional cardiac features of ARVC and is also a core modality in evaluation, however, tissue characterization of the right ventricle is limited by spatial resolution and low specificity for detection of pathological changes. Nonetheless, the ability of cardiac magnetic resonance to identify left ventricular involvement, offer high negative predictive value, and provide a reproducible structural evaluation of the right ventricle enhance the ability and scope of the modality. In this review, the prognostic significance of multimodality imaging is outlined, including the supplemental value of multidetector computed tomography and nuclear imaging. Strengths and weaknesses of imaging techniques, as well as future direction of multimodality assessment, are also described.

Associations Between HIV Serostatus and Cardiac Structure and Function Evaluated by 2-Dimensional Echocardiography in the Multicenter AIDS Cohort Study.

Background We aimed to investigate whether there are differences in cardiac structure and systolic and diastolic function evaluated by 2-dimensional echocardiography among men living with versus without HIV in the era of combination antiretroviral therapy. Methods and Results We performed a cross-sectional analysis of 1195 men from MACS (Multicenter AIDS Cohort Study) who completed a transthoracic echocardiogram examination between 2017 and 2019. Associations between HIV serostatus and echocardiographic indices were assessed by multivariable regression analyses, adjusting for demographics and cardiovascular risk factors. Among men who are HIV+, associations between HIV disease severity markers and echocardiographic parameters were also investigated. Average age was 57.1±11.9 years; 29% of the participants were Black, and 55% were HIV+. Most men who were HIV+ (77%) were virally suppressed; 92% received combination antiretroviral therapy. Prevalent left ventricular (LV) systolic dysfunction (ejection fraction <50%) was low and HIV serostatus was not associated with left ventricular ejection fraction. Multivariable adjustment models showed that men who were HIV+ versus those who were HIV- had greater LV mass index and larger left atrial diameter and right ventricular (RV) end-diastolic area; lower RV function; and higher prevalence of diastolic dysfunction. Higher current CD4+ T cell count ≥400 cell/mm3 versus <400 was associated with smaller LV diastolic volume and RV area. Virally suppressed men who were HIV+ versus those who were HIV- had higher indexed LV mass and left atrial areas and greater diastolic dysfunction. Conclusions HIV seropositivity was independently associated with greater LV mass index, left atrial and RV sizes, lower RV function and diastolic abnormalities, but not left ventricular ejection fraction, which may herald a future predisposition to heart failure with preserved ejection fraction among men living with HIV.

Baseline and Dynamic Risk Predictors of Appropriate Implantable Cardioverter Defibrillator Therapy.

Background Current approaches fail to separate patients at high versus low risk for ventricular arrhythmias owing to overreliance on a snapshot left ventricular ejection fraction measure. We used statistical machine learning to identify important cardiac imaging and time-varying risk predictors. Methods and Results Three hundred eighty-two cardiomyopathy patients (left ventricular ejection fraction ≤35%) underwent cardiac magnetic resonance before primary prevention implantable cardioverter defibrillator insertion. The primary end point was appropriate implantable cardioverter defibrillator discharge or sudden death. Patient characteristics; serum biomarkers of inflammation, neurohormonal status, and injury; and cardiac magnetic resonance-measured left ventricle and left atrial indices and myocardial scar burden were assessed at baseline. Time-varying covariates comprised interval heart failure hospitalizations and left ventricular ejection fractions. A random forest statistical method for survival, longitudinal, and multivariable outcomes incorporating baseline and time-varying variables was compared with (1) Seattle Heart Failure model scores and (2) random forest survival and Cox regression models incorporating baseline characteristics with and without imaging variables. Age averaged 57±13 years with 28% women, 66% white, 51% ischemic, and follow-up time of 5.9±2.3 years. The primary end point (n=75) occurred at 3.3±2.4 years. Random forest statistical method for survival, longitudinal, and multivariable outcomes with baseline and time-varying predictors had the highest area under the receiver operating curve, median 0.88 (95% CI, 0.75-0.96). Top predictors comprised heart failure hospitalization, left ventricle scar, left ventricle and left atrial volumes, left atrial function, and interleukin-6 level; heart failure accounted for 67% of the variation explained by the prediction, imaging 27%, and interleukin-6 2%. Serial left ventricular ejection fraction was not a significant predictor. Conclusions Hospitalization for heart failure and baseline cardiac metrics substantially improve ventricular arrhythmic risk prediction.

HIV Infection Is Associated With Variability in Ventricular Repolarization: The Multicenter AIDS Cohort Study (MACS).

BACKGROUND: People living with human immunodeficiency virus (HIV+) have greater risk for sudden arrhythmic death than HIV-uninfected (HIV-) individuals. HIV-associated abnormal cardiac repolarization may contribute to this risk. We investigated whether HIV serostatus is associated with ventricular repolarization lability by using the QT variability index (QTVI), defined as a log measure of QT-interval variance indexed to heart rate variance. METHODS: We studied 1123 men (589 HIV+ and 534 HIV-) from MACS (Multicenter AIDS Cohort Study), using the ZioXT ambulatory electrocardiography patch. Beat-to-beat analysis of up to 4 full days of electrocardiographic data per participant was performed using an automated algorithm (median analyzed duration [quartile 1-quartile 3]: 78.3 [66.3-83.0] hours/person). QTVI was modeled using linear mixed-effects models adjusted for demographics, cardiac risk factors, and HIV-related and inflammatory biomarkers. RESULTS: Mean (SD) age was 60.1 (11.9) years among HIV- and 54.2 (11.2) years among HIV+ participants (P<0.001), 83% of whom had undetectable (<20 copies/mL) HIV-1 viral load (VL). In comparison with HIV- men, HIV+ men had higher QTVI (adjusted difference of +0.077 [95% CI, +0.032 to +0.123]). The magnitude of this association depended on the degree of viremia, such that in HIV+ men with undetectable VL, adjusted QTVI was +0.064 (95% CI, +0.017 to +0.111) higher than in HIV- men, whereas, in HIV+ men with detectable VL, adjusted QTVI was higher by +0.150 (95% CI, 0.072-0.228) than in HIV- referents. Analysis of QTVI subcomponents showed that HIV+ men had: (1) lower heart rate variability irrespective of VL status, and (2) higher QT variability if they had detectable, but not with undetectable, VL, in comparison with HIV- men. Higher levels of C-reactive protein, interleukin-6, intercellular adhesion molecule-1, soluble tumor necrosis factor receptor 2, and soluble cluster of differentiation-163 (borderline), were associated with higher QTVI and partially attenuated the association with HIV serostatus. CONCLUSIONS: HIV+ men have greater beat-to-beat variability in QT interval (QTVI) than HIV- men, especially in the setting of HIV viremia and heightened inflammation. Among HIV+ men, higher QTVI suggests ventricular repolarization lability, which can increase susceptibility to arrhythmias, whereas lower heart rate variability signals a component of autonomic dysfunction.

Intravascular Stem Cell Bioreactor for Prevention of Adverse Remodeling After Myocardial Infarction.

Background Prevention of adverse remodeling after myocardial infarction (MI) is an important goal of stem cell therapy. Clinical trial results vary, however, and poor cell retention and survival after delivery likely limit the opportunity to exert beneficial effects. To overcome these limitations, we built an implantable intravascular bioreactor (IBR) designed to protect contained cells from washout, dilution, and immune attack while allowing sustained release of beneficial paracrine factors. Methods and Results IBRs were constructed using semipermeable membrane adhered to a clinical-grade catheter shaft. Mesenchymal stem cell (MSC) viability in and paracrine factor release from IBRs were assessed in vitro and IBR biocompatibility and immune protection confirmed in vivo. In a porcine anterior MI model, IBRs containing 25 million allogeneic MSCs (IBR-MSCs) were compared with IBRs containing media alone (IBR-Placebo; n=8 per group) with adverse remodeling assessed by magnetic resonance imaging. Four weeks after MI, IBR-MSCs had no significant change in end-diastolic volume (+0.33±4.32 mL; P=0.89), end-systolic volume (+2.14±4.13 mL; P=0.21), and left ventricular ejection fraction (-2.27±2.94; P=0.33) while IBR-Placebo had significant increases in end-diastolic volume (+10.37±3.84 mL; P=0.01) and ESV (+11.35±2.88 mL; P=0.01), and a significant decrease in left ventricular ejection fraction (-5.78±1.70; P=0.025). Eight weeks after MI, adherent pericarditis was present in 0 of 8 IBR-MSCs versus 4 of 8 IBR-Placebo (P=0.02), suggesting an anti-inflammatory effect. In a separate study, 25 million allogeneic pig MSCs directly injected in the peri-infarct zone 3 days after MI (n=6) showed no significant benefit in adverse remodeling at 4 weeks compared with IBR-MSCs. Conclusions MSCs deployed inside an implantable, removable, and potentially rechargeable bioreactor in a large animal model remain viable, are immunoprotected, and attenuate adverse remodeling 4 weeks after MI.

Predictors of electrocardiographic QT interval prolongation in men with HIV.

OBJECTIVE: HIV-infected (HIV+) individuals may be at increased risk for sudden arrhythmic cardiac death. Some studies have reported an association between HIV infection and prolongation of the electrocardiographic QT interval, a measure of ventricular repolarisation, which could potentiate ventricular arrhythmias. We aimed to assess whether HIV+ men have longer QT intervals than HIV-uninfected (HIV-) men and to determine factors associated with QT duration. METHODS: We performed resting 12-lead ECGs in 774 HIV+ and 652 HIV- men in the Multicenter AIDS Cohort Study (MACS). We used multivariable linear and logistic regression analyses to assess associations between HIV serostatus and Framingham corrected QT interval (QTc), after accounting for potential confounders. We also determined associations among QTc interval and HIV-related factors in HIV+ men. In a subgroup of participants, levels of serum markers of inflammation were also assessed. RESULTS: After adjusting for demographics and risk factors, QTc was 4.0 ms longer in HIV+ than HIV- men (p<0.001). Use of antiretroviral therapy (ART), specific ART drug class use and other HIV-specific risk factors were not associated with longer QTc. Among the subgroup with inflammatory biomarker measurements, higher interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1) and B-cell activating factor levels were independently associated with longer QTc and their inclusion partially attenuated the HIV effect. CONCLUSIONS: HIV+ men had longer QTc, which was associated with higher levels of systemic inflammatory factors. This longer QTc may contribute to the increased risk for sudden arrhythmic cardiac death in some HIV+ individuals.

Cardiovascular Magnetic Resonance to Predict Appropriate Implantable Cardioverter Defibrillator Therapy in Ischemic and Nonischemic Cardiomyopathy Patients Using Late Gadolinium Enhancement Border Zone: Comparison of Four Analysis Methods.

BACKGROUND: Late gadolinium enhancement (LGE) border zone on cardiac magnetic resonance imaging has been proposed as an independent predictor of ventricular arrhythmias. The purpose was to determine whether size and heterogeneity of LGE predict appropriate implantable cardioverter defibrillator (ICD) therapy in ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy (NICM) patients and to evaluate 4 LGE border-zone algorithms. METHODS AND RESULTS: ICM and NICM patients who underwent LGE cardiac magnetic resonance imaging prior to ICD implantation were retrospectively included. Two semiautomatic algorithms, expectation maximization, weighted intensity, a priori information and a weighted border zone algorithm, were compared with a modified full-width half-maximum and a 2-3SD threshold-based algorithm (2-3SD). Hazard ratios were calculated per 1% increase in LGE. A total of 74 ICM and 34 NICM were followed for 63 months (1-140) and 52 months (0-133), respectively. ICM patients had 27 appropriate ICD events, and NICM patients had 7 ICD events. In ICM patients with primary prophylactic ICD, LGE border zone predicted ICD therapy in univariable and multivariable analysis measured by the expectation maximization, weighted intensity, a priori information, weighted border zone, and modified full-width half-maximum algorithms (hazard ratios 1.23, 1.22, and 1.05, respectively; P<0.05; negative predictive value 92%). For NICM, total LGE by all 4 methods was the strongest predictor (hazard ratios, 1.03-1.04; P<0.05), though the number of events was small. CONCLUSIONS: Appropriate ICD therapy can be predicted in ICM patients with primary prevention ICD by quantifying the LGE border zone. In NICM patients, total LGE but not LGE border zone had predictive value for ICD therapy. However, the algorithms used affects the predictive value of these measures.

Screening for Cardiac Magnetic Resonance Scar Features by 12-Lead ECG, in Patients with Preserved Ejection Fraction.

BACKGROUND: Increased QRS score and wide spatial QRS-T angle are independent predictors of cardiovascular mortality in the general population. Our main objective was to assess whether a QRS score ≥ 5 and/or QRS-T angle ≥ 105° enable screening of patients for myocardial scar features. METHODS: Seventy-seven patients of age ≤ 70 years with QRS score ≥ 5 and/or spatial QRS-T angle ≥ 105° as well as left ventricular ejection fraction (LVEF) >35% were enrolled in the study. All participants underwent complete clinical examination, signal-averaged ECG (SAECG), 30-minute ambulatory ECG recording for T-wave alternans (TWA), and late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Relationship between QRS score, QRS-T angle with scar presence and pattern, as well as gray zone, core, and total scar size by LGE-CMR were assessed. RESULTS: Myocardial scar was present in 41 (53%) patients, of whom 19 (46%) exhibited a typical ischemic pattern. QRS score but not QRS-T angle was related to total scar size and gray zone size (R(2) = 0.12, P = 0.002; R(2) = 0.17; P ≤ 0.0001, respectively). Patients with QRS scores ≥ 6 had significantly greater myocardial scar and gray zone size, increased QRS duration and QRS-T angle, a higher prevalence of late potentials (LPs) presence, increased LV end-diastolic volume and decreased LVEF. There was a significant independent and positive association between TWA value and total scar (P = 0.001) and gray zone size (P = 0.01). CONCLUSION: Patients with preserved LVEF and myocardial scar by CMR also have electrocardiographic features that could be involved in ventricular arrhythmogenesis.

Brief report: antisynthetase syndrome-associated myocarditis.

BACKGROUND: The antisynthetase (AS) syndrome is characterized by autoimmune myopathy, interstitial lung disease, cutaneous involvement, arthritis, fever, and antibody specificity. We describe 2 patients with AS syndrome who also developed myocarditis, depressed biventricular function, and congestive heart failure. METHODS AND RESULTS: Both patients were diagnosed with AS syndrome based on clinical manifestations, detection of serum AS antibodies, and myositis confirmation with the use of skeletal muscle magnetic resonance imaging and skeletal muscle biopsy. In addition, myocarditis resulting in heart failure was confirmed with the use of cardiac magnetic resonance imaging and from endomyocardial biopsy findings. After treatment for presumed AS syndrome-associated myocarditis, one patient recovered and the other patient died. CONCLUSIONS: AS syndrome is a rare entity with morbidity and mortality typically attributed to myositis and lung involvement. This is the first report of AS syndrome-associated myocarditis leading to congestive heart failure in 2 patients. Given the potentially fatal consequences, myocarditis should be considered in patients with AS syndrome presenting with heart failure.

Down-regulation of argininosuccinate synthetase is associated with cisplatin resistance in hepatocellular carcinoma cell lines: implications for PEGylated arginine deiminase combination therapy.

BACKGROUND: Many advanced human tumors, including hepatocellular carcinomas (HCC) are auxotrophic for arginine due to down-regulation of argininosuccinate synthetase (ASS1), the rate-limiting enzyme in arginine synthesis. The arginine-lowering agent PEGylated arginine deiminase (ADI-PEG 20) has shown efficacy as a monotherapy in clinical trials for treating arginine-auxotrophic tumors and is currently being evaluated in combination with cisplatin in other cancer types. Epigenetic silencing via methylation of the ASS1 promoter has been previously demonstrated in other cancer types, and a reciprocal relationship between ASS1 expression and cisplatin resistance has also been observed in ovarian cancer. However, the mechanism of ASS1 down-regulation, as well as the correlation with cisplatin resistance has not been explored in HCC. The present study investigates ADI-PEG 20 and cisplatin sensitivities in relation to ASS1 expression in HCC. In addition, we show how this biomarker is regulated by cisplatin alone and in combination with ADI-PEG 20. METHODS: ASS1 protein expression in both untreated and drug treated human HCC cell lines was assessed by western blot. The correlation between ASS1 protein levels, ADI-PEG 20 sensitivity and cisplatin resistance in these cell lines was established using a luminescence-based cell viability assay. Epigenetic regulation of ASS1 was analyzed by bisulfite conversion and methylation-specific PCR. RESULTS: A good correlation between absence of ASS1 protein expression, ASS1 promoter methylation, sensitivity to ADI-PEG 20 and resistance to cisplatin in HCC cell lines was observed. In addition, cisplatin treatment down-regulated ASS1 protein expression in select HCC cell lines. While, at clinically relevant concentrations, the combination of ADI-PEG 20 and cisplatin restored ASS1 protein levels in most of the cell lines studied. CONCLUSION: ASS1 silencing in HCC cell lines is associated with simultaneous cisplatin resistance and ADI-PEG 20 sensitivity which suggests a promising combination therapeutic strategy for the management of HCC.