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Background: There are limited options for patients who present with antiarrhythmic-drug (AAD)-refractory ventricular tachycardia (VT) with recurrent implantable cardioverter defibrillator (ICD) shocks. Ranolazine is a drug that exerts antianginal and antiischemic effects and also acts as an antiarrhythmic in isolation and in combination with other class III medications. Ranolazine may be an option for recurrent AAD-refractory ICD shocks secondary to VT, but its efficacy, outcomes, and tolerance are unknown. Methods and Results: Twelve patients (age 65 ± 9.7 years) were treated with ranolazine. Eleven (92%) were male, and 10 (83%) had ischemic heart disease with an average ejection fraction of 0.34 ± 0.13. All patients were on a class III AAD (11 amiodarone, one sotalol), with six (50%) receiving mexilitene or lidocaine. Five patients had a prior ablation and two were referred for a VT ablation at the index presentation. The QRS increased nonsignificantly from 128 ± 31 ms to 133 ± 31 ms, and the QTc increased nonsignificantly from 486 ± 32 ms to 495 ± 31 ms after ranolazine initiation. Over a follow-up of 6 ± 6 months, 11 (92%) patients had a significant reduction in VT and no ICD shocks were observed. VT ablation was not required in those referred. In two patients, gastrointestinal side effects limited long-term use. Of these two patients, one died due to progressive heart failure. In one patient, severe hypoglycemia limited dosing to 500 mg daily, but this was sufficient for VT control. Conclusion: Ranolazine proved effective in reducing VT burden and ICD shocks in patients with AAD-refractory VT. Ranolazine should be further tested for this indication and considered for clinical application when other options have proven ineffective. (PACE 2011; 34:1600-1606) [ABSTRACT FROM AUTHOR]

Background: Previous studies have observed that short-term exposure to elevated concentrations of particulate matter (PM) air pollution increases risk of acute ischemic heart disease events and heart failure hospitalization, alters cardiac autonomic function, and increases risk of arrhythmias. This study explored the potential associations between short-term elevations in PM exposure and atrial fibrillation (AF). Methods and Results: A case-crossover study design was used to explore associations between fine PM (PM2.5, particles with an aerodynamic diameter ≤2.5 μm) and 10,457 AF hospitalizations from 1993 to 2008 of patients who lived on Utah's Wasatch Front. Patients were hospitalized at Intermountain Healthcare facilities with a primary diagnosis of AF. Concurrent day exposure and cumulative lagged exposures for up to 21 days were explored and the data were stratified by sex, age, and previous or subsequent admission for myocardial infarction. Although the estimated associations between PM2.5 and AF hospitalizations for the various lag structures and strata were consistently positive suggestive of risk, they were not statistically significant and they were extremely small compared to previously observed associations with ischemic heart disease events and heart failure hospitalizations. Further, we observed no additive risk between PM2.5 and AF hospitalization in those with respiratory disease or sleep apnea. Conclusions: Unlike previously observed associations with ischemic heart disease events and heart failure hospitalizations using similar study design and approaches, this study found that hospitalization for AF was not significantly associated with elevations in short-term exposure to fine PM air pollution. (PACE 2011; 34:1475-1479) [ABSTRACT FROM AUTHOR]

Outcomes in Patients With AF. Introduction: Atrial fibrillation (AF) adversely impacts mortality, stroke, heart failure, and dementia. AF ablation eliminates AF in most patients. We evaluated the long-term impact of AF ablation on mortality, heart failure (HF), stroke, and dementia in a large system-wide patient population. Methods: A total of 4,212 consecutive patients who underwent AF ablation were compared (1:4) to 16,848 age/gender matched controls with AF (no ablation) and 16,848 age/gender matched controls without AF. Patients were enrolled from the large ongoing prospective Intermountain AF study and were followed for at least 3 years. Results: Of the 37,908 patients, mean age 65.0 ± 13 years, 5,667 (14.9%) died, 1,296 (3.4%) had a stroke, and 1,096 (2.9%) were hospitalized for HF over >3 years of follow-up. AF ablation patients were less likely to have diabetes, but were more likely to have hypertension, HF, and significant valvular heart disease. AF ablation patients had a lower risk of death and stroke in comparison to AF patients without ablation. Alzheimer's dementia occurred in 0.2% of the AF ablation patients compared to 0.9% of the AF no ablation patients and 0.5% of the no AF patients (P < 0.0001). Other forms of dementia were also reduced significantly in those treated with ablation. Compared to patients with no AF, AF ablation patients had similar long-term rates of death, dementia, and stroke. Conclusions: AF ablation patients have a significantly lower risk of death, stroke, and dementia in comparison to AF patients without ablation. AF ablation may eliminate the increased risk of death and stroke associated with AF. (J Cardiovasc Electrophysiol, Vol. 22, pp. 839-845, August 2011) [ABSTRACT FROM AUTHOR]

Strategy of Rapid Cardioversion. Background: The significance of early recurrent atrial tachyarrhythmias after atrial fibrillation (AF) ablation is unclear. Atrial remodeling driven by these tachyarrhythmias can result in electrical, contractile, and structural changes that may impair long-term therapy success. Aggressive attempts to restore sinus rhythm in the temporal period of healing after ablation might improve outcomes. Methods: A total of 1,759 AF ablations were performed at Intermountain Medical Center or LDS Hospital. A total of 455 of those were among patients requiring repeat ablations. Patients were instructed to take their pulse daily and, if greater than 100 bpm or irregular, present the following business day fasting to the clinic for evaluation and cardioversion if AF or atrial flutter (AFL) were present. Results: Of the ablations performed, a total of 515 (29%, age: 65.6 ± 11.2 years, male: 57.9%) developed AF/AFL that required cardioverison. The majority of these arrhythmias first occurred in the initial 90 days (63.7%) postablation. During this period, 62.8% were on an antiarrhythmic drug (AAD). Only 25.1% were using an AAD at 3 months. The majority of ablations (75.6%) who experienced AF/AFL within the first 90 days after ablation were in sinus rhythm with no AAD at 1 year. Further, 48% of those with the first recurrence from 90 to 180 days were in sinus rhythm with no AAD at 1 year. Conclusions: The time at which the first recurrence of AF/AFL occurs impacts long-term outcomes. An aggressive strategy of rapid cardioversion postablation reduces the significance of recurrent AF/AFL during the first 6 months. (J Cardiovasc Electrophysiol, Vol. 22, pp. 761-766, July 2011) [ABSTRACT FROM AUTHOR]

Low vitamin D (serum or plasma 25-hydroxyvitamin D (25(OH)D)) is a global pandemic and associates with a greater prevalence in all-cause and cardiovascular mortality and morbidity. Open-heart surgery is a form of acute stress that decreases circulating 25(OH)D concentrations and exacerbates the preponderance of low vitamin D in a patient population already characterized by low levels. Although supplemental vitamin D increases 25(OH)D, it is unknown if supplemental vitamin D can overcome the decreases in circulating 25(OH)D induced by open-heart surgery. We sought to identify if supplemental vitamin D protects against the acute decrease in plasma 25(OH)D propagated by open-heart surgery during perioperative care. Participants undergoing open-heart surgery were randomly assigned (double-blind) to one of two groups: (a) vitamin D (n = 75; cholecalciferol, 50,000 IU/dose) or (b) placebo (n = 75). Participants received supplements on three separate occasions: orally the evening before surgery and either orally or per nasogastric tube on postoperative days 1 and 2. Plasma 25(OH)D concentrations were measured at baseline (the day before surgery and before the first supplement bolus), after surgery on postoperative days 1, 2, 3, and 4, at hospital discharge (5-8 days after surgery), and at an elective outpatient follow-up visit at 6 months. Supplemental vitamin D abolished the acute decrease in 25(OH)D induced by open-heart surgery during postoperative care. Moreover, plasma 25(OH)D gradually increased from baseline to day 3 and remained significantly increased thereafter but plateaued to discharge with supplemental vitamin D. We conclude that perioperative vitamin D supplementation protects against the immediate decrease in plasma 25(OH)D induced by open-heart surgery. ClinicalTrials.gov Identifier: NCT02460211., (© 2021 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Background: Survivors of acute myocardial infarction (MI) are at high risk for death from both sudden cardiac death and progressive heart failure., Objective: This study sought to determine mortality trends, identify markers of risk, and determine whether outcomes in high-risk patients are altered by revascularization during the implantable cardioverter-defibrillator candidacy observation period., Methods: We included 16,793 patients that presented to the catheterization laboratory for acute management of an MI. All patients had 3 years of follow-up to define short- and long-term mortality., Results: Across the demographics studied there were no significant differences in baseline characteristics over time, with exception of an observed decline in patients with an ejection fraction (EF) ≤0.35. Nonetheless, at study closure 16.3% of all cases had an EF ≤ 0.35. There was a gradual increase in use of percutaneous coronary intervention and coronary artery bypass graft; however, at the end of the study, the highest level of revascularization use was slightly >50%. For the composite, right and left bundle branch block or QRS > 120, the death rates at 1 and 5 years were 31.8% and 46.8%, respectively. These 1- and 5-year mortality rates were increased with an EF ≤ 0.35 (36.0%, 60.2%). Mortality in those with EF ≤ 0.35 exceeded 20% in all groups with conduction system disease at 90 days and was not significantly impacted by percutaneous coronary intervention., Conclusion: The highest risk for death after MI is in patients with an EF ≤ 0.35 and/or conduction system disease. The mortality risk is most pronounced in the early observation period after MI when patients must wait to be considered for an implantable cardioverter-defibrillator., (Copyright © 2011 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)