Coronary Artery Disease and Atherosclerotic Risk Factors in a Population-Based Study of Sudden Death.

BACKGROUND: Sudden death is a public health problem with major impact on society. Coronary artery disease (CAD) is believed to underlie 60-80% of these deaths. While deaths from CAD have decreased in the recent decades, sudden death rates remain unacceptably high. OBJECTIVE: We aimed to assess the prevalence of CAD and its risk factors among 18-64-year-old adults in a population-based case registry of sudden deaths and compare them to a living population from the same geographical area. DESIGN: From 2013 to 2015, all sudden deaths among 18-64-year-old adults in Wake County, NC, were identified (n = 371). A comparison group was formed by randomly selecting individuals from an electronic health record repository of a major healthcare system in the area (N = 4218). MAIN MEASURES: Prevalence of CAD and its risk factors among cases of sudden death and living population across sex and age groups. Odds of sudden death associated with atherosclerotic risk factors and comorbidities. KEY RESULTS: CAD was present in 14.8% of sudden death cases. Among sudden death victims, most risk factors and comorbidities were more common in the older age group, except for obesity which was more common in younger cases, and diabetes which was equally prevalent in younger and older cases. Compared to living population, sudden death cases had higher prevalence of atherosclerotic risk factors across all gender and age groups. Sudden death cases had a numerically higher number of risk factors compared to living population, regardless of age group or presence of CAD. CONCLUSIONS: Coronary artery disease is not common among sudden death cases, but risk factors and comorbidities are prevalent. Our findings support the changing etiology of sudden death. In the absence of clinically diagnosed CAD, use of novel imaging modalities and biomarkers may identify high-risk individuals and lead to prevention of sudden death.

The effect of anxiety and depression on symptoms attributed to atrial fibrillation.

BACKGROUND: Symptoms attributed to atrial fibrillation (AF) are nonspecific, and it remains unclear what influences perception of symptoms. Anxiety or depression may be important in modulating perception of AF symptoms. However, few longitudinal studies have addressed this effect. METHODS: A total of 378 patients with AF completed anxiety and depression severity questionnaires as well as AF symptom and frequency severity questionnaires. Patients were offered treatment strategies including catheter ablation or antiarrhythmic or rate-controlling medications. Patients were followed at 3-month intervals and completed follow-up questionnaires including repeat assessment of anxiety, depression, and AF symptoms. A method of generalized estimating equations was used for longitudinal analyses. RESULTS: Analysis revealed that increased anxiety or depression was associated with increased AF symptom severity (AFSS), after adjusting for potential confounders. In both unadjusted and adjusted follow-up analyses, antiarrhythmic drug therapy or catheter ablation reduced AFSS (P < 0.001). However, none of anxiety severity, depression severity, or the perception of AF frequency severity improved significantly with AF treatment. CONCLUSIONS: Our results extend previous studies demonstrating that anxiety and depression are associated with worsened AFSS. Antiarrhythmic drug therapy or catheter ablation reduces AFSS but does not affect depression and anxiety symptoms. To achieve more comprehensive AF symptom relief, treatment of both AF and psychological comorbidities may be beneficial.

Atrial fibrillation ablation using a closed irrigation radiofrequency ablation catheter.

BACKGROUND: Catheter ablation is an effective therapy for symptomatic, medically refractory atrial fibrillation (AF). Open-irrigated radiofrequency (RF) ablation catheters produce transmural lesions at the cost of increased fluid delivery. In vivo models suggest closed-irrigated RF catheters create equivalent lesions, but clinical outcomes are limited. METHODS: A cohort of 195 sequential patients with symptomatic AF underwent stepwise AF ablation (AFA) using a closed-irrigation ablation catheter. Recurrence of AF was monitored and outcomes were evaluated using Kaplan-Meier survival analysis and Cox proportional hazards models. RESULTS: Mean age was 59.0 years, 74.9% were male, 56.4% of patients were paroxysmal and mean duration of AF was 5.4 years. Patients had multiple comorbidities including hypertension (76.4%), tobacco abuse (42.1%), diabetes (17.4%), and obesity (mean body mass index 30.8). The median follow-up was 55.8 weeks. Overall event-free survival was 73.6% with one ablation and 77.4% after reablation (reablation rate was 8.7%). Median time to recurrence was 26.9 weeks. AF was more likely to recur in patients being treated with antiarrhythmic therapy at the time of last follow-up (recurrence rate 30.3% with antiarrhythmic drugs, 13.2% without antiarrhythmic drugs; hazard ratio [HR] 2.2, 95% confidence interval [CI] 1.1-4.4, P = 0.024) and in those with a history of AF greater than 2 years duration (HR 2.7, 95% CI 1.1-6.9, P = 0.038). CONCLUSIONS: Our study represents the largest cohort of patients receiving AFA with closed-irrigation ablation catheters. We demonstrate comparable outcomes to those previously reported in studies of open-irrigation ablation catheters. Given the theoretical benefits of a closed-irrigation system, a large head-to-head comparison using this catheter is warranted.

Improved Ablation Efficiency in PVI Guided by Contact Force and Local Impedance: Chronic Canine Model.

Background: The purpose of this study was to assess the effect local impedance (LI) has on an ablation workflow when combined with a contact force (CF) ablation catheter. Methods: Left pulmonary vein isolation was performed in an in vivo canine model (N = 8) using a nominal (30 W) or an elevated (50 W) power strategy with a CF catheter. The catheter was enabled to measure LI prior to and during ablation. LI was visible for only one of the vein isolations. Results: Chronic block was achieved in all animals when assessed 30 ± 5 days post-ablation procedure with a median LI drop during RF ranging from 23.0 to 34.0 Ω. In both power cohorts, the median radiofrequency (RF) duration decreased if LI was visible to the operator (30 W only CF: 17.0 s; 30 W CF + LI: 14.0 s, p = 0.009; 50 W only CF: 6.0 s; 50 W CF + LI: 4.0 s, p = 0.019). An inverse relationship between the LI prior to RF delivery and the RF duration required to achieve an effective lesion was observed. There was no correlation between the magnitude of the applied force and the drop in LI, once at least 5 g was achieved. Conclusions: An elevated power strategy with the context of CF and LI led to the most efficient titration of successful RF energy delivery. The combination of feedback allows for customization of the ablation strategy based on local tissue variation rather than a uniform approach that could potentially lead to overtreatment. Higher LI drops were more readily achievable when an elevated power strategy was utilized, especially in conditions where the catheter was coupled against tissue with low resistivity. Clinical study is warranted to determine if there is an additive safety benefit to visualizing the dynamics of the tissue response to RF energy with LI when an elevated power strategy is used.

Mental Disorders, Substance Use Disorders, and Psychotropic Medication Use Among Sudden-Death Victims.

OBJECTIVE: The authors sought to estimate the prevalence of mental and substance use disorders and psychotropic medication prescriptions among working-age sudden-death victims. METHODS: Using a written protocol, the authors screened for sudden deaths attended by emergency medical services (EMS) in a large metropolitan county in North Carolina from March 1, 2013, to February 28, 2015. Sudden-death cases were adjudicated by three cardiologists. Mental health and chronic disease diagnoses and treatments were abstracted from EMS, medical examiner, toxicology, and autopsy reports and from clinical records for the past 5 years before death. RESULTS: Sudden death was identified for 399 adults ages 18-64 years, 270 of whom had available medical records. Most sudden-death victims were White (63%) and male (65%), had a comorbid condition such as hypertension or respiratory disease, and had a mean±SD age of death of 53.6±8.8 years. Most victims (59%) had at least one mental health or substance use disorder documented in a recent medical record; 76%-78% of victims with a mental disorder had a documented psychotropic medication prescription. However, fewer than one-half (41%) had a documented referral to a mental health professional. The most common diagnostic categories were depressive, anxiety, and alcohol-related disorders. Almost one-half (46%) of the victims had a recent psychotropic prescription, most commonly antidepressants (29%) and benzodiazepines (19%). CONCLUSIONS: Mental illness, substance use disorders, and psychotropic medication prescriptions were prevalent among sudden-death victims. The health care needs of these individuals may be better addressed by collaborative care for general medical and mental disorders.

Accuracy of patient perception of their prevailing rhythm: a comparative analysis of monitor data and questionnaire responses in patients with atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) guidelines recommend that symptom relief be a primary goal in management. However, patient perception of their prevailing rhythm is often inaccurate, complicating symptom-targeted treatment. OBJECTIVE: The purpose of this study was to evaluate the accuracy of patient perception of their prevailing rhythm and identify factors that predict inaccuracies. METHODS: Demographic and health status data were captured by questionnaires for 458 outpatients with documented AF. AF burden (%) was captured by 1-week continuous heart monitors. Patients estimated the length and frequency of their AF episodes by completing the AF Symptom Severity questionnaire. Patient reports were compared to AF burden, and outliers were identified and broken into 2 groups: patients with AF burden <10% who indicated near-continuous AF (overestimators) and patients with AF burden >90% who estimated little to no AF (underestimators). Multinomial logistic regression was used to identify predictors of inaccuracies (over- or underestimators). RESULTS: By continuous monitor, 15% of patients were found to be over- or underestimators. Persistent AF, female sex, older age, anxiety, and depression were predictive of inaccurate patient perception. Persistent AF, female sex, and older age were predictive of underestimating, while mood disorders (anxiety and depression) were predictive of overestimating. The prevalence of underestimators was nearly twice that of overestimators. CONCLUSION: Sex, age, and mood disorders are among factors that lead to inaccurate patient perception of their prevailing rhythm in patients with AF. Such modulating factors should be considered when evaluating treatment strategies. Consideration should be given to more liberal use of heart monitors in these patient populations to better target therapy.

Effectiveness of atrial fibrillation monitor characteristics to predict severity of symptoms of atrial fibrillation.

The goal of treatment for atrial fibrillation (AF) is often to control symptoms. It remains unclear whether targets for treatment such as AF rate or AF burden are correlated with AF symptom severity. Two hundred eighty-six patients completed a questionnaire of their general health and well-being, including a detailed AF symptom assessment immediately followed by a 7-day continuous monitor. AF characteristics assessed from the monitor included AF burden, AF rate, sinus rhythm rate, frequency and severity of pauses, and premature atrial contraction or premature ventricular contraction burden. Characteristics were analyzed separately for patients with paroxysmal or persistent AF. Symptom severity was assessed using the University of Toronto Atrial Fibrillation Severity Scale. Monitor characteristics were compared with AF symptom severity. The mean age of the cohort was 61.8 years and the majority of subjects were male (65.4%). Co-morbidities included hypertension (64.5%), sleep apnea (38.4%), congestive heart failure (19.6%), and diabetes (16.4%). In those with persistent or paroxysmal AF, there were no significant predictors of AF symptom severity. Specifically, heart rate in AF or sinus rhythm, AF burden, or premature atrial contraction or premature ventricular contraction burden was not predictive of AF symptom severity. After adjusting for potential cofounders (including age, gender, and co-morbidities), these findings persisted. In conclusion, there is no value in using AF monitor characteristics to predict symptoms in patients with AF.

Sudden Unexpected Death in North Carolina (SUDDEN): methodology review and screening results.

OBJECTIVES: This paper describes the methodology for a prospective, community-based study of sudden unexpected death in Wake County, North Carolina. METHODS: From 1 March to 29 June 2013, data of presumed cardiac arrest cases were captured from Wake County Emergency Medical Services. Participants were screened into the presumed sudden unexpected death group based on specific and sequential screening criteria, and medical and public records were collected for each participant in this group. A committee of independent cardiologists reviewed all data to determine final inclusion/exclusion of each participant into registry. RESULTS: We received 398 presumed cardiac arrest referrals. Of these, 105 participants, age 18-65 years old, were identified as presumed sudden unexpected deaths. The primary reason for exclusion was survival to hospital (38%). Ninety-five per cent of participants in the presumed sudden unexpected death group experienced an unwitnessed death. Hypertension was present in almost 50%, while dyslipidaemia and diabetes mellitus were present in almost 25% of the same group. In addition, the presumed sudden unexpected death group includes 67.6% males (95% CI 58 to 76) whereas the control group only included 58.9% (95% CI 46 to 55) males. CONCLUSIONS: Participant identification and data collection processes identify presumed sudden unexpected death cases and secure medical and public data for screening and final adjudication. The study infrastructure developed in Wake County will allow its expansion to other counties in North Carolina. Preliminary data indicate the study presently focuses on a population demographically representative of North Carolina.

Effect of body mass index, physical activity, depression, and educational attainment on high-sensitivity C-reactive protein in patients with atrial fibrillation.

Atherosclerosis development is a complex process, with inflammation, indicated by elevated high-sensitivity C-reactive protein (hs-CRP), as a potential mediator. Obesity, physical activity, and depression have all been reported to affect hs-CRP. However, these factors are interconnected, and their relative individual importance remains unclear. From a separate prospective cohort study, 289 patients were selected for the present substudy. We assessed the relation of a variety of potential predictors and hs-CRP. Obesity, physical activity, and depression, in addition to several other potential factors, were analyzed in bivariate and multivariate linear regression models, adjusting for potential confounders. In unadjusted analyses, mild-to-moderate and severe depression were associated with increased hs-CRP compared to no or minimal depression. Vigorous physical activity was associated with decreased hs-CRP compared to no physical activity. All classes of obesity were associated with increased hs-CRP. In addition, attaining a college or graduate degree was associated with decreased hs-CRP compared to high school or less educational attainment. On multivariate analysis, depression was no longer associated with increased hs-CRP. Physical activity remained associated with decreased hs-CRP but only at vigorous levels. Educational attainment also remained associated but only at the collegiate or professional education level. Ultimately, obesity remained the greatest absolute predictor of elevated hs-CRP. In conclusion, in analyses of multiple factors potentially predictive of elevated hs-CRP in a large population of patients with subclinical coronary heart disease, we found the most important predictor to be obesity.