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21 result(s) for "Fenster, Brett E."
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Predictors of Cardiac Sarcoidosis Using Commonly Available Cardiac Studies
Cardiac involvement affects ≤40% of patients with sarcoidosis and accounts for ≤25% of deaths. The diagnosis of cardiac sarcoidosis is challenging using the existing screening tests and often relies on expensive cardiac magnetic resonance imaging (cMRI) and cardiac 18-fluorodeoxuyglucose positron emission tomography (FDG-cPET). We developed a scoring system using common clinical tests to predict positive imaging findings using cMRI or FDG-cPET. A retrospective chart review of subjects undergoing cMRI or FDG-cPET was performed. The data were extracted and scored using a predetermined system. Our cohort was predominantly white, with a mean age of 55 years, and 60% were women. The scoring system was compared with the findings from cMRI and FDG-cPET to determine the ability to predict the imaging results that define cardiac sarcoidosis. The scoring system for the patients who had undergone both FDG-cPET and cMRI suggested predictability, but the differences were not statistically significant. However, the positive results from just 1 study were as predictive as having positive findings from both studies. A 1-point increase in the total score increased the probability of positive findings from cMRI or FDG-cPET by 14% (95% confidence interval 3% to 25% increase; p = 0.01). The scoring system seemed to be driven more by the findings from cMRI than by those from FDG-cPET. In patients who had undergone cMRI alone, for each 1-point increase in the total score, the probability of positive cMRI findings increased 11% (95% confidence interval 1% decrease to 25% increase, p = 0.08). All screening modalities were analyzed. No modality was sensitive or specific, although major findings (defined in our scoring system) were most predictive of positive imaging findings. In conclusion, commonly available cardiac screening tools used together in a composite score provide reasonable results to predict positive cardiac sarcoidosis findings on imaging, but the system needs refinement. Our data suggest that major findings from screening studies are more likely to correlate with cMRI findings than with findings from FDG-cPET.
Effectiveness of Percutaneous Closure of Patent Foramen Ovale for Hypoxemia
The aim of this study was to evaluate the ability of percutaneous patent foramen ovale (PFO) closure to improve systemic hypoxemia. Although PFO-mediated right-to-left shunt (RTLS) is associated with hypoxemia, the ability of percutaneous closure to ameliorate hypoxemia is unknown. Between 2004 and 2009, 97 patients who underwent PFO closure for systemic hypoxemia and dyspnea that was disproportionate to underlying lung disease were included for evaluation. All patients exhibited PFO-mediated RTLS as determined by agitated saline echocardiography. Procedural success was defined as implantation of a device without major complications and mild or no residual shunt at 6 months. Clinical success was defined as a composite of an improvement in New York Heart Association (NYHA) functional class, reduction of dyspnea symptoms, or decreased oxygen requirement. Procedural success was achieved in 96 of 97 (99%), and clinical success was achieved in 68 of 97 (70%). The presence of any moderate or severe interatrial shunt by agitated saline study (odds ratio [OR] = 4.7; p <0.024), NYHA class at referral (OR = 2.9; p <0.0087), and 10-year increase in age (OR = 1.8; p <0.0017) increased likelihood of clinical success. In contrast, a pulmonary comorbidity (OR = 0.18; p <0.005) and male gender (OR = 0.30; p <0.017) decreased the likelihood of success. In conclusion, based on the largest single-center experience of patients referred for PFO closure for systemic hypoxemia, PFO closure was a mechanically effective procedure with an associated improvement in echocardiographic evidence of RTLS, NYHA functional class, and oxygen requirement.
Galectin-3 levels are associated with right ventricular functional and morphologic changes in pulmonary arterial hypertension
The response of the right ventricle (RV) to pulmonary arterial hypertension (PAH) involves changes in contractile function, chamber size, hypertrophy, and extracellular matrix (ECM). Galectin-3 (Gal-3) is a mediator of myocardial ECM metabolism and biomarker for left heart remodeling, yet its ability to reflect RV remodeling is unknown. We hypothesized that serum Gal-3 levels correlate with RV morphology and function in PAH, and that Gal-3 is associated with circulating markers of ECM. Fifteen subjects with PAH and 10 age-matched controls underwent same-day echocardiography, cardiac magnetic resonance (CMR) imaging, and phlebotomy for Gal-3 and ECM biomarkers including N-terminal propeptide of type III collagen type (PIIINP), tissue inhibitor of metalloproteinase-1 (TIMP-1), and hyaluronic acid (HA). RV ejection fraction, end diastolic volume index, end systolic volume index, and mass index were calculated using CMR. Echocardiography was used to estimate RV systolic pressure and measure RV strain. Serum Gal-3, TIMP-1, and HA levels were all significantly increased in PAH subjects when compared to controls. Gal-3 correlated with RV ejection fraction ( ρ −0.44, p 0.03), end diastolic volume index ( ρ 0.42, p 0.03), end systolic volume index ( ρ 0.44, p 0.027), mass index ( ρ 0.47, p 0.016), systolic pressure ( ρ 0.55, p  < 0.001), and strain ( ρ 0.43, p 0.03). Gal-3 levels positively correlated with the ECM markers TIMP-1 and HA but not with PIIINP. In conclusion, Gal-3 levels are associated with multiple indices of RV function and morphology. Gal-3 may represent a novel biomarker for RV remodeling and associated ECM turnover in PAH.
Acute and chronic impact of cardiovascular events on health state utilities
Background Cost-utility models are frequently used to compare treatments intended to prevent or delay the onset of cardiovascular events. Most published utilities represent post-event health states without incorporating the disutility of the event or reporting the time between the event and utility assessment. Therefore, this study estimated health state utilities representing cardiovascular conditions while distinguishing between acute impact including the cardiovascular event and the chronic post-event impact. Methods Health states were drafted and refined based on literature review, clinician interviews, and a pilot study. Three cardiovascular conditions were described: stroke, acute coronary syndrome (ACS), and heart failure. One-year acute health states represented the event and its immediate impact, and post-event health states represented chronic impact. UK general population respondents valued the health states in time trade-off tasks with time horizons of one year for acute states and ten years for chronic states. Results A total of 200 participants completed interviews (55% female; mean age = 46.6 y). Among acute health states, stroke had the lowest utility (0.33), followed by heart failure (0.60) and ACS (0.67). Utility scores for chronic health states followed the same pattern: stroke (0.52), heart failure (0.57), and ACS (0.82). For stroke and ACS, acute utilities were significantly lower than chronic post-event utilities (difference = 0.20 and 0.15, respectively; both p < 0.0001). Conclusions Results add to previously published utilities for cardiovascular events by distinguishing between chronic post-event health states and acute health states that include the event and its immediate impact. Findings suggest that acute versus chronic impact should be considered when selecting scores for use in cost-utility models. Thus, the current utilities provide a unique option that may be used to represent the acute and chronic impact of cardiovascular conditions in economic models comparing treatments that may delay or prevent the onset of cardiovascular events.
4D‐Flow MRI intracardiac flow analysis considering different subtypes of pulmonary hypertension
Intracardiac flow hemodynamic patterns have been considered to be an early sign of diastolic dysfunction. In this study we investigated right ventricular (RV) diastolic dysfunction between patients with pulmonary arterial hypertension (PAH) and pulmonary hypertension with chronic lung disease (PH‐CLD) via 4D‐Flow cardiac MRI (CMR). Patients underwent prospective, comprehensive CMR for function and size including 4D‐Flow CMR protocol for intracardiac flow visualization and analysis. RV early filling phase and peak atrial phase vorticity (E‐vorticity and A‐vorticity) values were calculated in all patients. Patients further underwent comprehensive Doppler and tissue Doppler evaluation for the RV diastolic dysfunction. In total 13 patients with PAH, 15 patients with PH‐CLD, and 10 control subjects underwent the 4D‐Flow CMR and echocardiography evaluation for RV diastolic dysfunction. Reduced E‐vorticity differentiated PAH and PH‐CLD from healthy controls (both p < 0.01) despite the same Doppler E values. E‐vorticity was further decreased in PAH patients when compared to PH‐CLD group (p < 0.05) with similar Doppler and tissue Doppler markers of diastolic dysfunction. A‐vorticity was decreased in both PAH and PH‐CLD groups compared to controls but with no difference between the disease groups. E‐vorticity correlated with ejection fraction (R = 0.60, p < 0.001), end‐systolic volume (R = 0.50, p = 0.001), stroke volume (R = 0.42, p = 0.007), and cardiac output (R = 0.30, p = 0.027). Intracardiac flow analysis using 4D‐Flow CMR derived vorticity is a sensitive method to differentiate diastolic dysfunction in patients with different PH etiology and similar Doppler echocardiography profile.
4D Flow Assessment of Vorticity in Right Ventricular Diastolic Dysfunction
Diastolic dysfunction, a leading cause of heart failure in the US, is a complex pathology which manifests morphological and hemodynamic changes in the heart and circulatory system. Recent advances in time-resolved phase-contrast cardiac magnetic resonance imaging (4D Flow) have allowed for characterization of blood flow in the right ventricle (RV) and right atrium (RA), including calculation of vorticity and qualitative visual assessment of coherent flow patterns. We hypothesize that right ventricular diastolic dysfunction (RVDD) is associated with changes in vorticity and right heart blood flow. This paper presents background on RVDD, and 4D Flow tools and techniques used for quantitative and qualitative analysis of cardiac flows in the normal and disease states. In this study, 20 patients with RVDD and 14 controls underwent cardiac 4D Flow and echocardiography. A method for determining the time-step for peak early diastole using 4D Flow data is described. Spatially integrated early diastolic vorticity was extracted from the RV, RA, and combined RV/RA regions of each subject using a range of vorticity thresholding and scaling methods. Statistically significant differences in vorticity were found in the RA and combined RA/RV in RVDD subjects compared to controls when vorticity vectors were both thresholded and scaled by cardiac index.
Endothelial dysfunction: clinical strategies for treating oxidant stress
A growing body of evidence has demonstrated that oxidants play a critical role in the pathogenesis of endothelial dysfunction. Pathologic processes fundamental to development and progression of endothelial dysfunction such as the oxidation of LDL, the loss of bioavailable nitric oxide, and the vascular inflammatory response are all modulated by oxidant stress. Therapeutic strategies to reverse endothelial dysfunction have begun to focus on agents with the ability to ameliorate oxidant stress. Preclinical and clinical studies evaluating the actions of antioxidants as well as traditional cardiovascular therapies in ameliorating oxidative stress and endothelial dysfunction were reviewed through the use of a MEDLINE search of English language articles published between the years of 1992 and 2002. Antioxidants appear to be an attractive candidate therapy, yet despite compelling preclinical evidence supporting their benefits, efforts to validate the use of vitamins C and E in a clinical setting have been conflicting. In contrast, conventional cardiovascular therapies such as ACE inhibitors, statins, insulin-sensitizing agents, and estrogens have been shown to alleviate endothelial dysfunction, often independent of their effects on systemic disease processes. These agents restore endothelial function through their salutary effects on pathologic vascular oxidative processes.
Abnormal pulmonary flow is associated with impaired right ventricular coupling in patients with COPD
Cor Pulmonale or right ventricular (RV) dysfunction due to pulmonary disease is an expected complication of COPD resulting primarily from increased afterload mediated by chronic alveolar hypoxemia and resulting hypoxic pulmonary vasoconstriction. Early detection of elevated RV afterload has been previously demonstrated by visualization of abnormal flow patterns in the proximal pulmonary arteries. Prior analysis of helicity in the pulmonary arteries in pulmonary hypertension patients has demonstrated a strong association between helicity and increased RV afterload. However, these flow hemodynamics have yet to be fully explored in patients with COPD. We hypothesized that patients with COPD will have abnormal pulmonary flow as evaluated by 4D-Flow MRI and associated with RV function and pulmonary arterial stiffness. Patients with COPD (n = 15) (65 years ± 6) and controls (n = 10) (58 years ± 9) underwent 4D-Flow MRI to calculate helicity. The helicity was calculated in the main pulmonary artery (MPA) and along the RV outflow tract (RVOT)—MPA axis. Main pulmonary arterial stiffness was measured using the relative area change (RAC). We found COPD patients had decreased helicity relative to healthy controls in the MPA (19.4 ± 7.8vs 32.8 ± 15.9, P = 0.007) and reduced helicity along the RVOT-MPA axis (33.2 ± 9.0 vs 43.5 ± 8.3, P = 0.010). Our investigation indicates a strong association between helicity along the MPA-RV outflow tract axis and RV function and suggests that 4D-Flow MRI might be a sensitive tool in evaluating RV—pulmonary arterial coupling in COPD.
Main Pulmonary Arterial Wall Shear Stress Correlates with Invasive Hemodynamics and Stiffness in Pulmonary Hypertension
Pulmonary hypertension (PH) is associated with proximal pulmonary arterial remodeling characterized by increased vessel diameter, wall thickening, and stiffness. In vivo assessment of wall shear stress (WSS) may provide insights into the relationships between pulmonary hemodynamics and vascular remodeling. We investigated the relationship between main pulmonary artery (MPA) WSS and pulmonary hemodynamics as well as markers of stiffness. As part of a prospective study, 17 PH patients and 5 controls underwent same-day four-dimensional flow cardiac magnetic resonance imaging (4-D CMR) and right heart catheterization. Streamwise velocity profiles were generated in the cross-sectional MPA in 45° increments from velocity vector fields determined by 4-D CMR. WSS was calculated as the product of hematocrit-dependent viscosity and shear rate generated from the spatial gradient of the velocity profiles. In-plane average MPA WSS was significantly decreased in the PH cohort compared with that in controls (0.18 ± 0.07 vs. 0.32 ± 0.08 N/m2; P = 0.01). In-plane MPA WSS showed strong inverse correlations with multiple hemodynamic indices, including pulmonary resistance (ρ = –0.74, P < 0.001), mean pulmonary pressure (ρ = –0.64, P = 0.006), and elastance (ρ = –0.70, P < 0.001). In addition, MPA WSS had significant associations with markers of stiffness, including capacitance (ρ = 0.67, P < 0.001), distensibility (ρ = 0.52, P = 0.013), and elastic modulus (ρ = –0.54, P = 0.01). In conclusion, MPA WSS is decreased in PH and is significantly associated with invasive hemodynamic indices and markers of stiffness. 4-D CMR-based assessment of WSS may represent a novel methodology to study blood-vessel wall interactions in PH.