13 research outputs found
Predictors and mechanisms of atrial fibrillation in patients with hypertrophic cardiomyopathy
Atrial fibrillation (AF) in hypertrophic cardiomyopathy (HC) is associated with significant symptomatic deterioration, heart failure, and thromboembolic disease. There is a need for better mechanistic insight and improved identification of at risk patients. We used cardiovascular magnetic resonance (CMR) to assess predictors of AF in HC, in particular the role of myocardial fibrosis. Consecutive patients with HC referred for CMR 2003 to 2013 were prospectively enrolled. CMR parameters including left ventricular volumes, presence and percentage of late gadolinium enhancement in the left ventricle (%LGE) and left atrial volume index (LAVi) were measured. Overall, 377 patients were recruited (age 62 ± 14 years, 73% men). Sixty-two patients (16%) developed new-onset AF during a median follow up of 4.5 (interquartile range 2.9 to 6.0) years. Multivariable analysis revealed %LGE (hazard ratio [HR] 1.3 per 10% (confidence interval: 1.0 to 1.5; p = 0.02), LAVi (HR 1.4 per 10 mL/m 2[1.2 to 1.5; p < 0.001]), age at HC diagnosis, nonsustained ventricular tachycardia and diabetes to be independent predictors of AF. We constructed a simple risk prediction score for future AF based on the multivariable model with a Harrell's C-statistic of 0.73. In conclusion, the extent of ventricular fibrosis and LA volume independently predicted AF in patients with HC. This finding suggests a mechanistic relation between fibrosis and future AF in HC. CMR with quantification of fibrosis has incremental value over LV and LA measurements in risk stratification for AF. A risk prediction score may be used to identify patients at high risk of future AF who may benefit from more intensive rhythm monitoring and a lower threshold for oral anticoagulation
Cardiovascular magnetic resonance predictors of heart failure in hypertrophic cardiomyopathy: the role of myocardial replacement fibrosis and the microcirculation
Introduction: Heart failure (HF) in hypertrophic cardiomyopathy (HCM) is associated with high morbidity and mortality. Predictors of HF, in particular the role of myocardial fibrosis and microvascular ischemia remain unclear. We assessed the predictive value of cardiovascular magnetic resonance (CMR) for development of HF in HCM in an observational cohort study. Methods: Serial patients with HCM underwent CMR, including adenosine first-pass perfusion, left atrial (LA) and left ventricular (LV) volumes indexed to body surface area (i) and late gadolinium enhancement (%LGE- as a % of total myocardial mass). We used a composite endpoint of HF death, cardiac transplantation, and progression to NYHA class III/IV. Results: A total of 543 patients with HCM underwent CMR, of whom 94 met the composite endpoint at baseline. The remaining 449 patients were followed for a median of 5.6 years. Thirty nine patients (8.7%) reached the composite endpoint of HF death (n = 7), cardiac transplantation (n = 2) and progression to NYHA class III/IV (n = 20). The annual incidence of HF was 2.0 per 100 person-years, 95% CI (1.6â2.6). Age, previous non-sustained ventricular tachycardia, LV end-systolic volume indexed to body surface area (LVESVI), LA volume index ; LV ejection fraction, %LGE and presence of mitral regurgitation were significant univariable predictors of HF, with LVESVI (Hazard ratio (HR) 1.44, 95% confidence interval (95% CI) 1.16â1.78, pâ=â0.001), %LGE per 10% (HR 1.44, 95%CI 1.14â1.82, pâ=â0.002) age (HR 1.37, 95% CI 1.06â1.77, pâ=â0.02) and mitral regurgitation (HR 2.6, pâ=â0.02) remaining independently predictive on multivariable analysis. The presence or extent of inducible perfusion defect assessed using a visual score did not predict outcome (pâ=â0.16, pâ=â0.27 respectively). Discussion: The annual incidence of HF in a contemporary ambulatory HCM population undergoing CMR is low. Myocardial fibrosis and LVESVI are strongly predictive of future HF, however CMR visual assessment of myocardial perfusion was not
Role matters in understanding âqualityâ in palliative care: a qualitative analysis of patient, caregiver and practitioner perspectives
Objectives To compare the discussions from two panels on the concept of palliative care quality for patients with advanced cancer, exploring the priorities reflected in each groupâs perspectives.Design We convened two RAND-UCLA appropriateness panel discussions on palliative care quality in advanced cancer. Discussions were audio-recorded and transcribed verbatim. Panel transcripts were analysed thematically using a matrix approach to examine perceptions and experiences of quality.Setting Discussions were framed within the context of advanced cancer care and palliative care.Participants The patientâcaregiver panel had 9 patients with current or a history of cancer and caregivers, and the practitioner panel had 10 expert practitioners representing fields of oncology, primary care, social work, palliative care, nursing, pain management and ethics.Results Our analysis identified three thematic categories for understanding quality common across both groups and nine subthemes within those categories. At the highest level, quality was conceived as: (1) the patient and caregiver experience of care, (2) technical competence and (3) the structure of health system. Among the subthemes, four were present in only one of the two groupâs discussions: âpurpose and actionâ was specific to the patientâcaregiver panel, whereas âadhering to best medical practiceâ, âmitigating unintended consequences and side effectsâ, and âhealth system resources and costsâ were specific to the practitioner panel.Conclusions While both panels aligned on the three key domains of quality, the particular dimensions through which they perceived quality varied in relation to their experience and role as a professional provider of care versus recipient of healthcare services. These differences suggest the importance of adopting a collaborative approach to quality measurement and improvement so that the values of all interested parties are represented in improvement efforts
Hyaluronic acid injection therapy for osteoarthritis of the knee: concordant efficacy and conflicting serious adverse events in two systematic reviews
Abstract Background The prevalence of knee osteoarthritis (OA)/degenerative joint disease (DJD) is increasing in the USA. Systematic reviews of treatment efficacy and adverse events (AEs) of hyaluronic acid (HA) injections report conflicting evidence about the balance of benefits and harms. We review evidence on efficacy and AEs of intraarticular viscosupplementation with HA in older individuals with knee osteoarthritis and account for differences in these conclusions from another systematic review. Methods We searched PubMed and eight other databases and gray literature sources from 1990 to December 12, 2014. Double-blind placebo-controlled randomized controlled trials (RCTs) reporting functional outcomes or quality-of-life; RCTs and observational studies on delay/avoidance of arthroplasty; RCTs, case reports, and large cohort studies and case series assessing safety; and systematic reviews reporting on knee pain were considered for inclusion. A standardized, pre-defined protocol was applied by two independent reviewers to screen titles and abstracts, review full text, and extract details on study design, interventions, outcomes, and quality. We compared our results with those of a prior systematic review and found them to be discrepant; our analysis of why this discrepancy occurred is the focus of this manuscript. Results Eighteen RCTs reported functional outcomes: pooled analysis of ten placebo-controlled, blinded trials showed a standardized mean difference of â0.23 (95 % confidence interval (CI) â0.45 to â0.01) favoring HA at 6Â months. Studies reported few serious adverse events (SAEs) and no significant differences in non-serious adverse events (NSAEs) (relative risk (RR) [95 % CI] 1.03 [0.93â1.15] or SAEs (RR [95 % CI] 1.39 [0.78â2.47]). A recent prior systematic review reported similar functional outcomes, but significant SAE risk. Differences in SAE inclusion and synthesis accounted for the disparate conclusions. Conclusions Trials show a small but significant effect of HA on function on which recent systematic reviews agree, but lack of AE synthesis standardization leads to opposite conclusions about the balance of benefits and harms. A limitation of the re-analysis of the prior systematic review is that it required imputation of missing data
Life Expectancy Predictions for Older Diabetic Patients as Estimated by Physicians and a Prognostic Model
Background: Multiple medical organizations recommend using life expectancy (LE) to individualize diabetes care goals. We compare the performance of patient LE predictions made by physicians to LE predictions from a simulation model (the Chicago model) in a cohort of older diabetic patients. Design: Retrospective cohort study of a convenience sample (n = 447) of diabetes patients over 65 years and their physicians. Measurements: Physicians provided LE estimates for individual patients during a baseline survey (2000â2003). The prognostic model included a comprehensive geriatric type 2 diabetes simulation model (the Chicago model) and combinations of the physician estimate and the Chicago model (âAnd,â âOr,â and âAverageâ models). Observed survival was determined based on the National Death Index through 31 December 2010. The predictive accuracy of LE predictions was assessed using c-statistic for 5-year mortality; Harrellâs c-statistic, and Integrated Brier score for overall survival. Results: The patient cohort had a mean (SD) age of 73.4 (5.9) years. The majority were female (62.6%) and black (79.4%). At 5 years, 108 (24.2%) patients had died. The c-statistic for 5-year mortality was similar for physicians (0.69) and the Chicago model (0.68), while the average of estimates by physicians and Chicago model yielded the highest c-statistic of any method tested (0.73). The estimates of overall survival yielded a similar pattern of results. Limitations: Generalizability of patient cohort and lack of updated model parameters. Conclusions: Compared with individual methods, the average of LE estimates by physicians and the Chicago model had the best predictive performance. Prognostic models, such as the Chicago model, may complement and support physiciansâ intuitions as they consider treatment decisions and goals for older patients with chronic conditions like diabetes
NIR-labeled perfluoropolyether nanoemulsions for drug delivery and imaging
Theranostic nanoparticle development recently took center stage in the field of drug delivery nanoreagent design. Theranostic nanoparticles combine therapeutic delivery systems (liposomes, micelles, nanoemulsions, etc.) with imaging reagents (MRI, optical, PET, CT). This combination allows for non-invasive in vivo monitoring of therapeutic nanoparticles in diseased organs and tissues. Here, we report a novel perfluoropolyether (PFPE) nanoemulsion with a water-insoluble lipophilic drug. The formulation enables non-invasive monitoring of nanoemulsion biodistribution using two imaging modalities, (19)F MRI and near-infrared (NIR) optical imaging. The nanoemulsion is composed of PFPE-tyramide as a (19)F MRI tracer, hydrocarbon oil, surfactants, and a NIR dye. Preparation utilizes a combination of self-assembly and high energy emulsification methods, resulting in droplets with average diameter 180 nm and low polydispersity index (PDI less than 0.2). A model nonsteroidal anti-inflammatory drug (NSAID), celecoxib, was incorporated into the formulation at 0.2 mg/mL. The reported nanoemulsionâs properties, including small particle size, visibility under (19)F NMR and NIR fluorescence spectroscopy, and the ability to carry drugs make it an attractive potential theranostic agent for cancer imaging and treatment