Utility of serial measurement of biomarkers of cardiovascular stress and inflammation in systolic dysfunction.

AIMS: Evidence links markers of systemic inflammation and heart failure (HF) with ventricular arrhythmias (VA) and/or death. Biomarker levels, and the risk they indicate, may vary over time. We evaluated the utility of serial laboratory measurements of inflammatory biomarkers and HF, using time-dependent analysis. METHODS AND RESULTS: We prospectively enrolled ambulatory patients with left ventricular ejection fraction (LVEF) ≤35% and a primary-prevention implanted cardioverter-defibrillator (ICD). Levels of established inflammatory biomarkers [C-reactive protein, erythrocyte sedimentation rate (ESR), suppression of tumourigenicity 2 (ST2), tumour necrosis factor alpha (TNF-α)] and brain natriuretic peptide (BNP) were assessed at 3-month intervals for 1 year. We assessed relationships between biomarkers modelled as time-dependent variables, VA, and death. Among 196 patients (66±14 years, LVEF 23±8%), 33 experienced VA, and 18 died. Using only baseline values, BNP predicted VA, and both BNP and ST2 predicted death. Using serial measurements at 3-month intervals, time-varying BNP independently predicted VA, and time-varying ST2 independently predicted death. C-statistic analysis revealed no significant benefit to repeated testing compared with baseline-only measurement. C-reactive protein, ESR, and TNF-α, either at baseline or over time, did not predict either endpoint. CONCLUSION: In stable ambulatory patients with systolic cardiomyopathy and an ICD, BNP predicts ventricular tachyarrhythmia, and ST2 predicts death. Repeated laboratory measurements over a year's time do not improve risk stratification beyond baseline measurement alone. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov NCT01892462 (https://clinicaltrials.gov/ct2/show/NCT01892462).

Current Evidence-Based Understanding of the Epidemiology, Prevention, and Treatment of Atrial Fibrillation.

Atrial fibrillation (AF) is the most common atrial arrhythmia in adults worldwide. As medical advancements continue to contribute to an ever-increasing aging population, the burden of atrial fibrillation on the modern health care system continues to increase. Therapies are also evolving, for treatment of the arrhythmia itself, and stroke risk mitigation. Internists and cardiologists alike are, in most instances, the frontline contact for AF patients, and would benefit from remaining facile in their understanding of care options. To continue to deliver high-quality care to this expanding patient group, an updated, concise review for the clinician is prudent. This article provides a comprehensive summary of the current epidemiology and pathophysiology of AF, as well as contemporary procedural therapeutic options.

Sinus Bradycardia in Habitual Cocaine Users.

Common physiological manifestations of cocaine are related to its adrenergic effects, due to inhibition of dopamine and norepinephrine uptake at the postsynaptic terminal. Few studies have documented bradycardia secondary to cocaine use, representing the antithesis of its adrenergic effects. We assessed the prevalence of sinus bradycardia (SB) in habitual cocaine users and postulated a mechanism for this effect. One hundred sixty-two patients with a history of cocaine use were analyzed and compared with age- and gender-matched controls. SB was defined as a rate of <60 beats/min and habitual cocaine use as 2 or more documented uses >30 days apart. Propensity score-matching analysis was applied to balance covariates between cocaine users and nonusers and reduce selection bias. Patients with a history of bradycardia, hypothyroidism, or concomitant beta-blocker use were excluded. Mean age of study patients was 44 ± 8 years. SB was observed in 43 of 162 (27%) cocaine users and in 9 of 149 (6%) nonusers (p = 0.0001). Propensity score-matching analysis matched 218 patients from both groups. Among matched patients SB was observed in 25 of 109 (23%) cocaine users and in 5 of 109 (5%) nonusers (p = 0.0001). Habitual cocaine use was an independent predictor of SB and associated with a sevenfold increase in the risk of SB (95% CI 2.52 to 19.74, p = 0.0002). In conclusion, habitual cocaine use is a strong predictor of SB and was unrelated to recency of use. A potential mechanism for SB may be related to cocaine-induced desensitization of the beta-adrenergic receptor secondary to continuous exposure. Symptomatic SB was not observed; thus, pacemaker therapy was not indicated.

The State of the Art: Atrial Fibrillation Epidemiology, Prevention, and Treatment.

As the most common sustained arrhythmia in adults, atrial fibrillation (AF) is an established and growing epidemic. To provide optimal patient care, it is important for clinicians to be aware of AF's epidemiological trends, methods of risk reduction, and the various available treatment modalities. Our understanding of AF's pathophysiology has advanced, and with this new understanding has come advancements in prevention strategies as well as pharmacological and nonpharmacological treatment options. Following PubMed and MEDLINE searches for AF risk factors, epidemiology, and therapies, we reviewed relevant articles (and bibliographies of those articles) published from 2000 to 2016. This "state-of-the-art" review provides a comprehensive update on the understanding of AF in the world today, contemporary therapeutic options, and directions of ongoing and future study.

Atrial fibrillation and heart failure: update 2015.

Heart failure (HF) and atrial fibrillation (AF) commonly coexist, adversely affect mortality, and impose a significant burden on healthcare resources. The presence of AF and HF portends a poor prognosis as well as an increased thromboembolic risk. In patients whose AF is symptomatic, rhythm restoration with either antiarrhythmic drugs or procedural therapies (e.g., pulmonary vein isolation, either catheter-based or surgical) should be considered for symptom improvement, though a mortality benefit has yet to be demonstrated. Emerging evidence suggests that non-pharmacological treatment for AF (including catheter based ablation, hybrid surgical techniques, and atrioventricular node ablation with biventricular pacing) may be of value in improving HF patients' quality of life.

Atrial fibrillation and congestive heart failure.

Heart failure (HF) and atrial fibrillation (AF) commonly coexist and adversely affect mortality when found together. AF begets HF and HF begets AF. Rhythm restoration with antiarrhythmic drugs failed to show a mortality benefit but can be effective in improving symptoms. Nonpharmacologic treatment of AF may be of value in the HF population.