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Atrial fibrillation (AF) is an arrhythmia characterized by disorganized atrial activity with an associated unevenly irregular ventricular response on an electrocardiogram. It is the most common sustained arrhythmia, with a lifetime risk of 25% in patients older than 40 years old. The incidence of AF increases with age and is associated with an increased risk for heart failure, stroke, adverse cardiac events, and dementia. The 2 main aims of AF treatment include anticoagulation for thromboembolism prophylaxis as well as rate vs rhythm control. The focus of this article will be on the treatment strategies in managing AF. Rate control refers to the use of atrioventricular nodal blocking medications, including beta blockers and calcium channel blockers, to maintain a goal heart rate. Rhythm control, on the other hand, refers to a treatment strategy focused on the use of antiarrhythmic drugs (AAD), cardioversion, and ablation to restore and to maintain a patient in sinus rhythm. Currently, the ideal treatment strategy remains greatly debated. Thus, we hope to compare the risks and benefits of rate to rhythm control to highlight how patients with AF are managed here at Kaiser Permanente Northern California. [ABSTRACT FROM AUTHOR]

Aims: Outcomes among patients who do not receive device reimplantation after cardiovascular implantable electronic device (CIED) extraction have not been well studied. The present study aims to investigate the outcomes of patients without device reimplantation after lead extraction and device removal.Methods and Results: We retrospectively searched for consecutive patients who underwent CIED extraction at Mayo Clinic, Rochester, MN and University of California San Diego Medical Center from 2001 through 2012. Among the patients identified, we compared characteristics of those who did and did not have device reimplantation. The Kaplan-Meier survival was analysed. Among 678 patients, 97 patients had their device extracted without reimplantation during 1-year follow-up ('no-reimplant group'). Median age was younger in the no-reimplant group (60.7 vs. 70.6 years; P < 0.001). The reasons for no reimplantation were as follows: no longer meeting criteria for CIED (48%), inappropriate device indication at initial implantation (23%), patient preference (17%), and unresolved device complications (12%). Three major arrhythmias were reported in the no-reimplant group. Overall survival in the no-reimplant group was significantly lower than in the reimplant group (60 vs. 93%; P < 0.001). Ongoing device-related complications [hazard ratio (HR), 3.91; 95% CI, 1.74-8.81; P = 0.001], infection (HR, 3.06; 95% CI, 1.24-7.52; P = 0.02), and concurrent dialysis (HR, 2.74; 95% CI, 1.12-6.71; P = 0.03) were associated with increased mortality. Of 31 deaths in the no-reimplant group, 1 was secondary to cardiac arrhythmia.Conclusion: Fourteen per cent of patients who had device extraction did not undergo reimplantation mainly because they no longer met CIED indications. The high mortality in these patients is related to device complications and comorbid conditions, whereas mortality associated with arrhythmia is rare. [ABSTRACT FROM AUTHOR]

Background: Unintentional pediatric cocaine exposures are rare but concerning due to potentially serious complications such as seizures, dysrhythmias, and death.Objectives: The objectives were to assess the demographic and clinical characteristics of pediatric cocaine exposures reported to the California Poison Control System.Methods: This is a retrospective study of all confirmed pediatric (< 6 years of age) cocaine exposures reported to the California Poison Control System from January 1, 1997-September 30, 2010. Case narratives were reviewed for patient demographics, exposure details, clinical effects, therapy, hospitalization, and final outcome.Results: Of the 86 reported pediatric cocaine exposures, 36 had positive urine drug testing and were included in the study cohort. The median age at presentation was 18 months (range: 0-48 months), and 56% were male (n = 20). The most common clinical manifestations were tachycardia and seizures. The most common disposition was admission to an intensive care unit (n = 14; 39%). Eleven cases (31%) were classified as having a major effect as per American Association of Poison Control Centers case coding guidelines. One child presented in asystole with return of spontaneous circulation after cardiopulmonary resuscitation and multiple vasoactive medications. The proportion of cocaine exposures with serious (moderate or major) outcomes (66.7%; 95% confidence interval 50.3-79.8%) was higher than other pediatric poisonings reported to the American Association of Poison Control Centers during the study period (0.88%; 95% confidence interval 0.87-0.88).Conclusions: Although pediatric cocaine exposures are rare, they result in more severe outcomes than most unintentional pediatric poisonings. Practitioners need to be aware of the risk of recurrent seizures and cardiovascular collapse associated with cocaine poisoning. [ABSTRACT FROM AUTHOR]

Conserved Rotors in Recurrent AF Introduction Recurrent atrial fibrillation (AF) after ablation is associated with reconnection of initially isolated pulmonary vein (PV) trigger sites. Substrates are often targeted in addition to PVI, but it is unclear how substrates progress over time. We studied if substrates in recurrent AF are conserved or have developed de novo from pre-ablation AF. Methods and Results Of 137 patients undergoing Focal Impulse and Rotor Mapping (FIRM) at their index procedure for AF, 29 consecutive patients (60 ± 8 years, 79% persistent) recurred and were also mapped at repeat procedure (21 ± 20 months later) using carefully placed 64-pole baskets and RhythmViewTM (Topera, Menlo Park, CA, USA) to identify AF sources and disorganized zones. Compared to index AF, recurrent AF had a longer cycle length (177 ± 21 vs. 167 ± 19 milliseconds, P = 0.01). All patients (100%) had 1 or more conserved AF rotors between procedures with surrounding disorganization. The number of sources was similar for recurrent AF post-PVI versus index AF (3.2 ± 1.4 vs. 3.1 ± 1.0, P = 0.79), but was lower for recurrent AF after FIRM+PVI versus index AF (4.4 ± 1.4 vs. 2.9 ± 1.7, P = 0.03). Overall, 81% (61/75) of AF sources lay in conserved regions, while 19% (14/75) were detected de novo. Conclusion Electrical propagation patterns for recurrent AF after unsuccessful ablation are similar in individual patients to their index AF. These data support temporospatial stability of AF substrates over 1-2 years. Trials should determine the relative benefit of adding substrate mapping and ablation to PVI for recurrent AF. [ABSTRACT FROM AUTHOR]

Background Frequent premature ventricular contractions (PVCs) can cause a reversible reduction in systolic function. Most studies use 24-hour ambulatory electrocardiograms (AECGs) to assess PVC burden; however, PVC counts vary across 24-hour periods. We hypothesized that extended AECG monitoring would better identify clinically significant ectopy. Methods All 14-day AECGs performed at the San Francisco Veterans Affairs Medical Center between 2012 and 2015 (N = 694) were reviewed, and individuals with PVC counts ≥1.0% of total heartbeats were included (N = 101). Daily PVC counts and the range of these values across 24-hour periods were assessed. Median time for these ranges to cross clinically significant thresholds (PVCs ≥ 10%, 15%, or 20% of total heartbeats) was determined. Results Median PVC burden was 2.6% of total heartbeats (interquartile range [IQR]: 1.6-5.4%) and the median range across 24-hour periods was 3.6% (IQR: 2.0-9.1%). Individual ranges of daily PVC burden crossed thresholds of 10%, 15%, and 20% of total heartbeats in 26.7%, 16.8%, and 6.9% of patients, respectively. Median time to detecting an individual's maximum PVC burden was 6 days (IQR: 2-11 days). While 75% of those who reached the 20% threshold did so on day one of monitoring, only 53% of those reaching the 10% threshold did similarly, with a continually increasing yield throughout the 14-day monitoring period. Conclusions PVC burden varies widely from day-to-day. While most patients with PVC burdens ≥20% were detected with 24 hours of monitoring, extended monitoring nearly doubled the identification of those reaching the 10% threshold. [ABSTRACT FROM AUTHOR]

Cardiovascular Disease (CVD) is one of the most catastrophic and life threatening health issue nowadays. Early detection of CVD is an important solution to reduce its devastating effects on health. In this paper, an efficient CVD detection algorithm is identified. The algorithm uses patient demographic data as inputs, along with several ECG signal features extracted automatically through signal processing techniques. Cross-validation results show a 98.29 % accuracy for the decision tree classification algorithm. The algorithm has been integrated into a web based system that can be used at anytime by patients to check their heart health status. At one end of the system is the ECG sensor attached to the patient's body, while at the other end is the detection algorithm. Communication between the two ends is done through an Android application. [ABSTRACT FROM AUTHOR]

Background: Intravenous amiodarone is an important treatment for arrhythmias, but peripheral infusion is associated with direct irritation of vessel walls and phlebitis rates of 8% to 55%. Objectives: To determine the incidence and factors contributing to the development of amiodarone-induced phlebitis in the coronary care unit in an academic medical center and to refine the current practice protocol. Methods: Medical records from all adult patients during an 18-month period who received intravenous amiodarone while in the critical care unit were reviewed retrospectively. Route of administration, location, concentration, and duration of amiodarone therapy and factors associated with occurrence of phlebitis were examined. Descriptive statistics and regression methods were used to identify incidence and phlebitis factors. Results: In the final sample of 105 patients, incidence of phlebitis was 40%, with a 50% recurrence rate. All cases of phlebitis occurred in patients given a total dose of 3 g via a peripheral catheter, and one-quarter of these cases (n = 10) developed at dosages less than 1 g. Pain, redness, and warmth were the most common indications of phlebitis. Total dosage given via a peripheral catheter, duration of infusion, and number of catheters were significantly associated with phlebitis. Conclusions: Amiodarone-induced phlebitis occurred in 40% of this sample at higher drug dosages. A new practice protocol resulted from this study. An outcome study is in progress. [ABSTRACT FROM AUTHOR]

MVI Block vs Trigger Ablation in PMFL. Introduction: Patients with previous ablation for atrial fibrillation (AF) may experience recurrence of perimitral flutter (PMFL). These arrhythmias are usually triggered from sources that may also induce AF. This study aims at determining whether ablation of triggers or completing mitral valve isthmus (MVI) block prevents more arrhythmia recurrences. Methods and Results: Sixty-five patients with recurrent PMFL after initial ablation of long standing persistent AF were included in this study. Thirty-two patients were randomized to MVI ablation only (Group 1) and 33 were randomized to cardioversion and repeat pulmonary vein (PV) isolation plus ablation of non-PV triggers (Group 2). MVI bidirectional block was achieved in all but 1 patient from Group 1. In Group 2, reconnection of 17 PVs was detected in 14 patients (42%). With isoproterenol challenge, 44 non-PV trigger sites were identified in 28 patients (85%, 1.57 sites per patient). At 18-month follow-up, 27 patients (84%) from Group 1 had recurrent atrial tachyarrhythmias, of whom 15 remained on antiarrhythmic drug (AAD); however, 28 patients from Group 2 (85%, P < 0.0001 vs Group 1) were free from arrhythmia off AAD. The ablation strategy used in Group 2 was associated with a lower risk of recurrence (hazard ratio = 0.10, 95% CI 0.04-0.28, P < 0.001) and an improved arrhythmia-free survival (log rank P < 0.0001). Conclusion: In patients presenting with PMFL after ablation for longstanding persistent AF, MVI block had limited impact on arrhythmia recurrence. On the other hand, elimination of all PV and non-PV triggers achieved higher freedom from atrial arrhythmias at follow-up. (J Cardiovasc Electrophysiol, Vol. 23, pp. 137-144, February 2012) [ABSTRACT FROM AUTHOR]

This article continues a series of reports summarising recent research developments of particular interest to those involved in the management of patients with heart failure. A number of relevant presentations were made at the American Heart Association Scientific Sessions in Anaheim, California, between 11–14 November 2001. Summaries of the following Clinical Trials are included: The Heart Protection Study, IONA, CARISA, ENRICHD, ACUTE, ALIVE, MADIT II and REMATCH. [Copyright &y& Elsevier]

The author conveys her concerns on a study about cannabis concentrate use in adolescents. Topics mentioned include an increase in the use of electronic cigarettes (e-cigarettes) and vaporizers by youth in the U.S., an increase in the average potency of tetrahydrocannabinol in cannabis from the 1980s to 2019, and efforts to offer better prevention and education about the consequences of marijuana and e-cigarette and/or vaporizer use.

Background: Digoxin remains commonly used for rate control in atrial fibrillation, but limited data exist supporting this practice and some studies have shown an association with adverse outcomes. We examined the independent association between digoxin and risks of death and hospitalization in adults with incident atrial fibrillation and no heart failure., Methods and Results: We performed a retrospective cohort study of 14,787 age, sex, and high-dimensional propensity score-matched adults with incident atrial fibrillation and no previous heart failure or digoxin use in the AnTicoagulation and Risk factors In Atrial fibrillation-Cardiovascular Research Network (ATRIA-CVRN) study within Kaiser Permanente Northern and Southern California. We examined the independent association between newly initiated digoxin and the risks of death and hospitalization using extended Cox regression. During a median 1.17 (interquartile range, 0.49-1.97) years of follow-up among matched patients with atrial fibrillation, incident digoxin use was associated with higher rates of death (8.3 versus 4.9 per 100 person-years; P<0.001) and hospitalization (60.1 versus 37.2 per 100 person-years; P<0.001). Incident digoxin use was independently associated with a 71% higher risk of death (hazard ratio, 1.71; 95% confidence interval, 1.52-1.93) and a 63% higher risk of hospitalization (hazard ratio, 1.63; 95% confidence interval, 1.56-1.71). Results were consistent in subgroups of age and sex and when using intent-to-treat or on-treatment analytic approaches., Conclusions: In adults with atrial fibrillation, digoxin use was independently associated with higher risks of death and hospitalization. Given other available rate control options, digoxin should be used with caution in the management of atrial fibrillation., (© 2014 American Heart Association, Inc.)

Presents a calendar of international events related to pacing and clinical electrophysiology from November 3, 1999 to September 16, 2001. Practical Pediatric Electrophysiology & Pacing conference in California; The "New Frontiers" of Arrhytmias 2000: 14th International Congress in Italy; The New World of Cardiology conference in Florida.

This article presents information on meetings and programs related to cardiac pacing. The Island Symposium on Cardiac Pacing, Coronary Angioplasty and Arrhythmia Management (CME) will be held on February 5-8 in The Royal Waikoloan, Hawaii. A program on the Examination of Special Competency in Cardiac Pacing for the non-physician Associated Professionals will be held on May 30 in San Diego Marriott Hotel and Marina San Diego, California.

This article focuses on the performance of implantable cardiac rhythm management devices at the Pacemaker Center, University of Southern California School of Medicine, Los Angeles, California. The article presents two tables. The first table presents data related to implantable cardioversion defibrillating device failures from July 1, 1989 to September 30, 1989. Another table presents data related to implantable cardioversion defibrillating devices from March 1, 1982 to September 30,1989.

Background and Purpose: It is unknown whether supraventricular arrhythmias other than atrial fibrillation or flutter are associated with stroke., Methods: To examine the association between paroxysmal supraventricular tachycardia (PSVT) and stroke, we performed a retrospective cohort study using administrative claims data from all emergency department encounters and hospitalizations at California's nonfederal acute care hospitals in 2009. Our cohort comprised all adult patients with ≥ 1 emergency department visit or hospitalization from which they were discharged alive and without a diagnosis of stroke. Our primary exposure was a diagnosis of PSVT recorded at an encounter before stroke or documented as present-on-admission at the time of stroke. To reduce confounding, we excluded patients with diagnoses of atrial fibrillation. We defined PSVT, stroke, and atrial fibrillation using International Classification of Diseases, Ninth Revision, Clinical Modification codes previously validated by detailed chart review., Results: Of 4 806 830 eligible patients, 14 121 (0.29%) were diagnosed with PSVT and 14 402 (0.30%) experienced a stroke. The cumulative rate of stroke after PSVT diagnosis (0.94%; 95% confidence interval, 0.76%-1.16%) significantly exceeded the rate among patients without a diagnosis of PSVT (0.21%; 95% confidence interval, 0.21%-0.22%). In Cox proportional hazards analysis controlling for demographic characteristics and potential confounders, PSVT was independently associated with a higher risk of subsequent stroke (hazard ratio, 2.10; 95% confidence interval, 1.69-2.62)., Conclusions: In a large and demographically diverse sample of patients, we found an independent association between PSVT and ischemic stroke. PSVT seems to be a novel risk factor that may account for some proportion of strokes that are currently classified as cryptogenic.