Search

The article examines the effectiveness and risks of pulsed field ablation (PFA) for atrial fibrillation, comparing it with thermal ablation. Topics include the comparison between pulsed field ablation (PFA) and thermal ablation for atrial fibrillation in the ADVENT trial, highlighting PFA's shorter procedure times, disappointing efficacy outcomes despite successful pulmonary vein isolation, and safety concerns regarding potential esophageal injury.

The author reflects on the Book of the Dead and the impact of epicardial fat on atrial fibrillation (AF) vulnerability. Topics discussed include factors attributed to the increase in AF, interesting findings that implicate both obesity and right atrial pacing as mediators of AF vulnerability through similar pathways, and shorter effective refractory periods in the pulmonary veins demonstrated by animals exposed to right atrial pacing.

Atrial fibrillation is associated with multiple adverse comorbidities, including the development of dementia in patients with and without a history of stroke. Mechanistic models have been proposed to explain the association of AF and dementia. Alterations of brain perfusion from embolic events, bleeding, and rhythm-related hypoperfusion underlie many of these models. Multiple mediators such as oxidative injury, inflammatory and autoimmune mechanisms, and genetic predisposition also interplay in the disease association. There are potential therapeutic opportunities to reduce dementia risk, including early and effective use of anticoagulation and strategies to improve brain perfusion through rhythm and rate control approaches. Prospective trials are needed to evaluate these therapeutic opportunities that carefully measure cognitive function and dementia incidence. [ABSTRACT FROM AUTHOR]

Abstract: Background: Catheter ablation of atrial fibrillation (AF) is an established therapeutic rhythm approach. Patients with a prior history of a stroke (CVA) represent a unique high‐risk population for recurrent thromboembolic events. The role of antiarrhythmic treatment on the natural history of stroke recurrence in these patients is not fully understood. Methods: Three patient groups with a prior CVA and 5 years of follow‐up were matched 1:3:3 by propensity score (±0.01): AF ablation patients receiving their first ablation (n  =  139), AF patients that did not receive an ablation (n  =  416), and CVA patients without clinical AF (n  =  416). Prior CVA was determined by medical chart review. Patients were followed for outcomes of recurrent CVA, heart failure, and death. Results: The average age of the population was 69 ± 11 years and 51% male. AF ablation patients had higher rates of hypertension and heart failure (P < 0.0001), but diabetes prevalence was similar between the groups (P  =  0.5). Note that 5‐year risk of CVA (HR  =  2.26, P < 0.0001) and death (HR  =  2.43, P < 0.0001) were higher in the AF, no ablation group compared those that were ablated. When comparing AF, ablation to no AF patients, there was not a significant difference in 5‐year risk of for CVA (HR  =  0.82, P  =  0.39) and death (HR  =  0.92, P  =  0.70); however, heart failure risk was increased (HR  =  3.08, P  =  0.001). Conclusion: In patients with AF and a prior CVA, patients undergoing ablation have lower rates of recurrent stroke compared to AF patients not ablated. Although the full mechanisms of benefit are unknown, as CVA rates are similar to patients without AF these data are suggestive of a potential altering of the natural history of disease progression. [ABSTRACT FROM AUTHOR]

Impact of Age After Atrial Fibrillation Catheter Ablation Background Catheter ablation of atrial fibrillation (AF) is an established therapeutic rhythm approach in symptomatic patients. Many studies have shown that age has little to no impact on outcomes during the first year after ablation. However, AF is a disease of aging and age-based substrate for arrhythmia is likely to progress. To this regard, we examined patients with 5-year outcome data following an index AF ablation procedure to define the impact of age on long-term outcomes. Methods A total of 923 patients that underwent their index AF ablation and had 5 years of follow-up were studied. Patients were followed up for atrial flutter/AF recurrence, heart failure, stroke, death, and cardiac function. Patients were separated and compared in 5 age-based groups (<50, 51-60, 61-70, 71-80, >80). Results The average age of the population was 66 ± 11 years and 59% were male. The AF was paroxysmal in 55%, persistent in 27%, and longstanding persistent in 18%. Older patients were more likely female and had higher rates of cardiovascular diseases. For every 10-year increase in age there was a higher multivariate-adjusted risk of atrial flutter/AF recurrence (HR: 1.13, P = 0.01), death (HR:1.91, P < 0.0001), and major adverse cardiac events (HR: 1.09, P = 0.07). Although atrial flutter/AF recurrence rates by age were similar at 1 year, at 5 years, younger patients had significantly lower rates of recurrences. Conclusion Age significantly impacts outcomes after AF ablation when analyzed with long-term follow-up. These data highlight the progressive nature of AF and the need to consider interventions early. [ABSTRACT FROM AUTHOR]

An editorial is presented on the effects of excessive contact force on the benefits of irrigated tip catheter during atrial fibrillation ablation. It explores a study by Okumura and colleagues which revealed the association of excessive contact force with increased risk of developing tissue tenting and reduced risk of transmural lesion, demonstrating the irrigated-catheter performance with force-sensing feedback.

Aim: This post hoc analysis evaluated efficacy and safety of dronedarone in atrial fibrillation (AF) and atrial flutter (AFL) patients with/without diabetes.Methods: Patients were categorized according to baseline diabetes status. Time-to-event analyses were performed using Kaplan-Meier method. Hazard-ratios were assessed using Cox models.Results: 945/4628 (dronedarone = 482; placebo = 463) patients in ATHENA and 215/1237 (dronedarone = 148; placebo = 67) patients in EURIDIS/ADONIS studies had diabetes. In ATHENA, there were higher rates of CV hospitalization/death in patients with diabetes (39.5%) than without diabetes (34.7%). Incidence of first CV hospitalization/death was lower in patients with diabetes treated with dronedarone (35.1%) than placebo (44.1%), and time to this event was longer in those treated with dronedarone than placebo (log-rank p = 0.005). Median AF/AFL recurrence time was longer in patients treated with dronedarone than placebo in patients with diabetes (ATHENA: 722 vs 527 days, log-rank p = 0.004; EURIDIS/ADONIS: 100 vs 23 days, log-rank p = 0.15) or without diabetes (ATHENA: 741 vs 492 days, log-rank p < 0.0001; EURIDIS/ADONIS: 120 vs 59 days, log-rank p = 0.0002). Occurrence of any treatment-related adverse events with dronedarone was similar for patients with/without diabetes and was comparable to placebo.Conclusions: Dronedarone reduced incidence of CV hospitalization/death, AF/AFL recurrence and increased time to these events in AF/AFL patients with/without diabetes.Trial Registration: Not applicable, as it was a post hoc analysis. This article is based on previously conducted studies (ATHENA: NCT00174785, EURIDIS: NCT00259428, and ADONIS: NCT00259376). [ABSTRACT FROM AUTHOR]

Catheter Ablation and Long-Term Outcomes Background Catheter ablation of atrial fibrillation (AF) is an established therapy for symptomatic patients. The long-term efficacy and impact of catheter ablation among patients with severe systolic heart failure (SHF) requires additional study to understand if outcomes achieved at 1 year are maintained and mechanisms of AF recurrence. Methods Three groups with SHF and 5 years of follow-up were matched 1:4:4 by age (±5 years) and sex: AF ablation patients receiving their first ablation (n = 267), AF patients that did not receive an ablation (n = 1,068), and SHF patient without AF (n = 1,068). SHF was based upon clinical diagnosis and an ejection fraction (EF) ≤35%. Patients were followed for 5-year primary outcomes of AF recurrence, heart failure, stroke, death, and cardiac function. Results At 5 years, 60.7% of patients had clinical recurrence of AF. Diabetes and a prior heart attack were significant predictors of long-term risk of AF recurrence. Long-term mortality rates were 27%, 55%, 50%, in the AF ablation, AF, and no AF groups, respectively (P < 0.0001), with the lower rates attributed to lower cardiovascular mortality. At 5 years, there was no difference in EF, yet HF hospitalizations were lower following AF ablation compared to patients with AF and no ablation. Stroke rates at 5 years trended to be lower in the AF ablation group, but the difference was not statistically significant. Conclusion Recurrence rates of AF in patients with SHF after ablation are common at 5 years with an anticipated ongoing increase. Long-term AF-related comorbidities tended to be less in the AF ablation group. [ABSTRACT FROM AUTHOR]

Introduction: Early and safe ambulation can facilitate same‐day discharge (SDD) following catheter ablation, which can reduce resource utilization and healthcare costs and improve patient satisfaction. This study evaluated procedure success and safety of the VASCADE MVP venous vascular closure system in patients with atrial fibrillation (AF). Methods: The AMBULATE SDD Registry is a two‐stage series of postmarket studies in patients with paroxysmal or persistent AF undergoing catheter ablation followed by femoral venous access‐site closure with VASCADE MVP. Efficacy endpoints included SDD success, defined as the proportion of patients discharged the same day who did not require next‐day hospital intervention for procedure/access site–related complications, and access site sustained success within 15 days of the procedure. Results: Overall, 354 patients were included in the pooled study population, 151 (42.7%) treated for paroxysmal AF and 203 (57.3%) for persistent AF. SDD was achieved in 323 patients (91.2%) and, of these, 320 (99.1%) did not require subsequent hospital intervention based on all study performance outcomes. Nearly all patients (350 of 354; 98.9%) achieved total study success, with no subsequent hospital intervention required. No major access‐site complications were recorded. Patients who had SDD were more likely to report procedure satisfaction than patients who stayed overnight. Conclusion: In this study, 99.7% of patients achieving SDD required no additional hospital intervention for access site–related complications during follow‐up. SDD appears feasible and safe for eligible patients after catheter ablation for paroxysmal or persistent AF in which the VASCADE MVP is used for venous access‐site closure. [ABSTRACT FROM AUTHOR]

The authors discuss the Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM), in which rhythm control was compared with rate control in patients with atrial fibrillation. Topics include differences between rhythm control and rate control, benefits of advances in atrial fibrillation rhythm control, and the strongest predictor of survival in AFFIRM.

Intracardiac Ultrasound During Left Atrial Ablation for Atrial Fibrillation. Background: Esophageal injury during left atrial ablation is associated with a significant risk of mortality and morbidity. There are no validated approaches to reduce injury outside of avoidance, a strategy critically dependent on a precise understanding of the esophageal anatomy and location. Intracardiac ultrasound (ICE) can provide a real-time assessment of the esophagus during ablation. We hypothesized that ICE can accurately define esophageal anatomy and location to enhance avoidance strategies during ablation. Methods: Fifty patients underwent atrial fibrillation (AF) ablation. The left atrium and pulmonary vein anatomies were rendered by traditional electroanatomic mapping (CARTO). A Navistar catheter within the esophagus was used to create a traditional electroanatomic esophageal anatomy. ICE imaging was used to create a second geometry of the esophagus. The traditional and ICE anatomies of the esophagus were compared and the greatest border dimensions used to avoid injury. Results: The average age was 66 ± 10 years, 45% had persistent/longstanding persistent AF, and 18% had a prior AF ablation. The esophagus location was leftward in 17 (34%), midline in 22 (44%), and rightward in 11 (22%). Traditional esophagus and ICE imaging correlated within 1 cm in the greatest distance in 26 (52%) patients. Traditional imaging underestimated the esophageal location by >1-1.5 cm in 9 (18%) and >1.5 cm in 15 (30%). In those with poor correlation (>1.5 cm), the most common cause was the presence of a hiatal hernia. Ablation energy delivery was performed outside the greatest esophagus anatomy borders. Of those with 12-month follow-up, 75% were AF/atrial flutter free without antiarrhythmic drugs. No esophageal injuries were observed. One patient experienced a TIA greater than 6 months postablation. Conclusion: These data demonstrate that traditional means of mapping the esophagus using a catheter within the esophagus are insufficient and often grossly underestimate the actual anatomy. Imaging techniques that define the complete esophageal lumen should be considered to truly minimize esophageal injury risk. (J Cardiovasc Electrophysiol, Vol. 24, pp. 33-39, January 2013) [ABSTRACT FROM AUTHOR]

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]

Atrial fibrillation (AF) is a common disorder that significantly impacts the lives of affected patients. The restoration of sinus rhythm may prevent AF progression and reduce the occurrence of negative sequelae; however, available antiarrhythmic drugs (AADs) have largely failed to demonstrate significant benefit relative to rate control with respect to morbidity and mortality outcomes. The review commentary will address current knowledge regarding the pathologic mechanisms of AF, current trials that investigate rate and rhythm strategies, and future therapies that may change treatment approaches based on preliminary evidence suggesting a more favorable safety profile. The observed outcomes are likely a reflection of the limited efficacy plus poor safety and tolerability of available AADS. However, data from patients who attained and maintained sinus rhythm in a number of clinical studies demonstrate that the achievement of normal sinus rhythm can indeed reduce AF-associated morbidity and mortality. Furthermore, the results of trials designed to assess specific morbidity and mortality outcomes such as cardiovascular death hospitalization suggest that the development of safer AF therapies, whether pharmacologic or nonpharmacologic, can potentially improve clinical outcomes. [ABSTRACT FROM AUTHOR]

Background: Ablation of ventricular tachycardia (VT) reduces implantable cardioverter defibrillator shocks. Intracardiac ultrasound (ICE) can visualize and quantify the function of all left ventricular wall segments. We thus hypothesized that ICE could identify scar tissue and provide a guide to facilitate substrate-guided VT ablation. Methods: Eighteen patients underwent VT ablation with real time ICE mapping from the right atrium and ventricle with online 3D-image reconstruction of scar segments. The left ventricle was also scar mapped by traditional electroanatomic mapping (CARTO) for comparison. Images from these 2 scar mapping techniques were compared to each other as well as to a preprocedure transthoracic echocardiogram. Results: The average age was 65 ± 12 years and 12 (67%) were male (15 [83%] had ischemic cardiomyopathy). Two patients (12%) had recurrence of their clinical VT (1 remained on an antiarrhythmic medication, the other had a repeat ablation) over a follow-up of 127 ± 33 days. No periprocedural or long-term adverse events occurred. A total of 248 wall segments were analyzed. All 3 modalities were concordant in scar identification in 193 (78%) segments. The ICE segments correlated with the electroanatomic map in 213 (86%) segments versus 198 (80%), which correlated with transthoracic echocardiography and electroanatomic mapping (P = 0.046). Specifically, the ICE wall motion scores were closer to the electroanatomic mapping in the basal segments and showed a higher accuracy in ischemic heart disease. Conclusion: These data demonstrate that real time ICE images provide accurate chamber geometries and scar boundaries of the left ventricle. These scar borders were more accurate than transthoracic echocardiography and illustrate the feasibility of ICE for substrate-based ablation for VT. (J Cardiovasc Electrophysiol, Vol. 21, pp. 678-684, June 2010) [ABSTRACT FROM AUTHOR]

Background: Radiofrequency ablation is an effective treatment for atrial fibrillation (AF). With improved safety, the therapy has been offered to increasingly older populations. Arrhythmia mechanisms, medical comorbidities, and safety may vary in the very elderly population. Methods: Patients presenting for AF ablation were divided into two groups [≥80 years (n = 35), <80 years (n = 717)]. AF ablation consisted of pulmonary vein antral isolation with or without additional linear lesions. A successful outcome was defined as no further AF and off all antiarrhythmic medications >3 months following 1 + ablation procedures. Results: The type of AF was similar in both groups (paroxysmal: 46% in the older group vs 54% in the younger, P = 0.33). Older patients were more likely to have a higher CHADS2 score, coronary artery disease, and less likely to have had a prior ablation. The hospital stay on average was longer in the older cohort (2.9 ± 7.7 vs 2.1 ± 1.1 days, P = 0.001). There was no increased risk of peri-procedural complications. One-year survival free of AF or flutter was 78% in those >80 and 75% in those younger (P = 0.78). There was no difference between groups if the AF was paroxysmal (P = 0.44) or persistent/chronic (P = 0.74). Over a 3-year follow-up period, five patients died and four strokes occurred all in the younger cohort. Conclusion: Octogenarian patients, despite more coexistent cardiovascular diseases, have favorable outcomes after AF ablation measured by successful rhythm management. On an average their hospital stay is longer, but no significant increase in short- or long-term complications was observed. These data support AF ablation in select octogenarians. (PACE 2010; 33:146–152) [ABSTRACT FROM AUTHOR]

Background: The recently published HRS/EHRA/ECAS AF Ablation Consensus Statement recommended that warfarin should be used for at least 2 months following an AF ablation in all patients regardless of stroke risk factors. The objective of the study was to assess outcomes based upon anticoagulation practice after atrial fibrillation (AF) ablation to determine relative risk of a strategy of aspirin only in low-risk patients. Methods: A total of 630 consecutive patients who underwent 934 ablation procedures using an open irrigated tip catheter for symptomatic AF were evaluated. Outcomes were compared between patients treated with warfarin (goal INR: 2–3) versus aspirin only (325 mg/day) in CHADS2 0–1 patients after ablation. Results: Of the 690 patients, 123 (20%) were treated with aspirin and 507 (80%) with warfarin. Prevalences of the CHADS2 scores of patients on aspirin were (0: 40.7%, 1: 59.3%) and on warfarin (0: 13.6%, 1: 31.6%, ≥2: 54.8%), P < 0.0001. Patients in the warfarin group were older, had on average a lower ejection fraction, and had higher rates persistent/permanent AF, repeat ablations, hypertension, prior stroke/TIA, and diabetes. The 1-year survival free of AF for the total study population was 71.6%. There were no strokes/TIA in the aspirin group and 4 events (4 strokes, 0 TIAs) in the warfarin group. Two patients in the warfarin group died of fatal hemorrhage (1 intracranial, 1 gastrointestinal). Conclusion: Select low-risk patients with a low CHADS2 (0–1) score who undergo left atrial ablation with an aggressive anticoagulation strategy with heparin and use of an open irrigated tip catheter with low CHADS2 scores can safely be discharged following their procedure on aspirin alone. [ABSTRACT FROM AUTHOR]

The approach to catheter-based radiofrequency ablation of atrial fibrillation has evolved, and as a consequence, more energy is delivered in the posterior left atrium, exposing neighboring tissue to untoward thermal injury. Simultaneously, catheter technology has advanced to allow more efficient energy delivery into the myocardium, which compounds the likelihood of collateral injury. This review focuses on the basic principles of thermodynamics as they apply to energy delivery during radiofrequency ablation. These principles can be used to titrate energy delivery and plan ablative approaches in an effort to minimize complications during the procedure. [ABSTRACT FROM AUTHOR]

Bisphosphonates comprise the most common treatment for patients with osteoporosis and fracture risk. Large randomized trials have shown that these therapies may increase the risk of atrial fibrillation (AF). Controversy over the arrhythmia risk prompted the Federal Drug Administration to recently pursue an ongoing safety review to determine the cardiac risk across the entire drug class. Study patients came from 2 large prospective databases (ongoing registry of consecutive patients who underwent coronary angiography and the Intermountain Healthcare health plans database). Medical details regarding bisphosphonate use and cardiovascular risk factors were abstracted from the records. End points included AF, myocardial infarction, and death. In the angiographic database (n = 9,623), patients treated with bisphosphonates were older and more likely to have hypertension, a previous myocardial infarction, heart failure, and osteoporosis. Over 1,481 ± 1,024 days we found no increased risk of AF in the drug-treated group (hazard ratio 0.90, 95% confidence interval 0.48 to 1.68, p = 0.74). In the Intermountain Healthcare health plans database (n = 37,485), patients treated with bisphosphonates were older and were more likely to have hyperlipidemia and osteoporosis. Over 1,667.5 ± 557.0 days, there was no increased risk of AF (hazard ratio 0.82, 95% confidence interval 0.66 to 1.01, p = 0.63). In the 2 databases there was no statistical difference in long-term rates of myocardial infarction or mortality. In conclusion, in a long-term study of >47,000 patients, we were unable to find an association between bisphosphonate therapy and AF. However, patients who received bisphosphonates were older and had more cardiovascular disease that we suspect accounts for the increased arrhythmia risk reported in other trials. [Copyright &y& Elsevier]

Atrial fibrillation (AF) and heart failure (HF) are two conditions regularly encountered in clinical practice. They share many common risk factors, and are often seen concurrently in an individual patient. Global aging of the population is likely to lead to an increase in the prevalence of both AF and HF alone, as well as in their combined state. The relationship between these two diseases is not simply coincidental; clinical and experimental data have defined multiple pathophysiological mechanisms to explain how either condition contributes to the de novo development of the other. The development of AF in the setting of HF, and vice versa, is associated with clinical deterioration and worsening prognosis, which indicates the need for an improved understanding of the clinical and pathological relationships between these conditions. Future research on pharmacologic therapies, such as antiarrhythmic medications, and nonpharmacologic strategies including atrioventricular nodal ablation and pulmonary vein isolation, will help to define the optimal therapeutic approach for concurrent AF and HF. This step is vital to improve both the outcomes of patients affected by these conditions and the cost-effectiveness of their care. [ABSTRACT FROM AUTHOR]

Background: Hypertrophic cardiomyopathy (HCM) is often accompanied by atrial fibrillation (AF) due to diastolic dysfunction, elevated left atrial pressure, and enlargement. Although catheter ablation for drug-refractory AF is an effective treatment, the efficacy in HCM remains to be established. Methods: Thirty-three consecutive patients (25 male, age 51 ± 11 years) with HCM underwent pulmonary vein (PV) isolation (n = 8) or wide area circumferential ablation with additional linear ablation (n = 25) for drug-refractory AF. Twelve-lead and 24-hour ambulating ECGs, echocardiograms, event monitor strips, and SF 36 quality of life (QOL) surveys were obtained before ablation and for routine follow-up. Results: Twenty-one (64%) patients had paroxysmal AF and 12 (36%) had persistent/permanent AF for 6.2 ± 5.2 years. The average ejection fraction was 0.63 ± 0.12. The average left atrial volume index was 70 ± 24 mL/m 2 . Over a follow-up of 1.5 ± 1.2 years, 1-year survival with AF elimination was 62%(Confidence Interval [CI]: 66-84) and with AF control was 75%(CI: 66-84). AF control was less likely in patients with a persistent/chronic AF, larger left atrial volumes, and more advanced diastolic disease. Additional linear ablation may improve outcomes in patient with severe left atrial enlargement and more advanced diastolic dysfunction. Two patients had a periprocedureal TIA, one PV stenosis, and one died after mitral valve replacement from prosthetic valve thrombosis. QOL scores improved from baseline at 3 and 12 months. Conclusion: Outcomes after AF ablation in patients with HCM are favorable. Diastolic dysfunction, left atrial enlargement, and AF subtype influence outcomes. Future studies of rhythm management approaches in HCM patients are required to clarify the optimal clinical approach. [ABSTRACT FROM AUTHOR]

Traditional cardiovascular risk factors have been shown to cause microvascular dysfunction. Most studies that have evaluated microcirculation rely on invasive measurement tools. We used dobutamine stress echocardiography, a validated method to measure coronary flow velocity (CFV) and coronary flow reserve (CFR), in a previously unstudied population without known significant coronary artery disease to determine the impact of traditional risk factors on CFR. Consecutive patients who had no evidence of regional wall motion abnormalities at rest or during dobutamine stress echocardiography were studied. Left anterior descending artery CFV was measured at baseline and at peak dobutamine stress and CFR was calculated as the ratio of peak stress CFV to baseline CFV. Fifty-nine consecutive patients (28 men) with mean age of 66.8 ± 14.5 years were studied. CFR was lower in patients with diabetes mellitus (DM) compared with those without (1.7 ± 0.74 vs 2.48 ± 0.98, p <0.007), in patients with hypertension compared with those without (2 ± 0.8 vs 2.6 ± 0.9, p <0.02), and in obese patients compared with nonobese patients (1.6 ± 0.5 vs 2 ± 0.6, p <0.02). CFR was further impaired in the presence of DM with hypertension, DM with obesity, DM with a wide pulse pressure (>50 mm Hg), and obesity with a wide pulse pressure. In a multivariate model, DM, obesity, and wide pulse pressure were significantly associated with variation in CFR (p <0.0008). In conclusion, CFR was abnormal in patients with DM, hypertension, and obesity. CFR impairment is exaggerated as the number of risk factors increases. Despite a negative dobutamine stress echocardiographic result, aggressive risk factor assessment and control should be implemented in patients with coronary risk factors due to an underlying abnormal CFR. [Copyright &y& Elsevier]

Summary: Aim: Studies have shown an association between obesity and total mortality among people with and without coronary artery disease. This study reviews outcomes among obese survivors of ventricular fibrillation in out-of-hospital cardiac arrest. Methods: All survivors of ventricular fibrillation in out-of-hospital cardiac arrest who presented in Rochester, MN from November 1990 to September 2006 were included and classified by body weight. Implantable cardioverter defibrillator shocks administered were determined by review of subsequent device interrogations. Results: Among a study population of 226, 99 (44%) survived to hospital discharge with neurological recovery. Data to calculate body mass index were available in 213 cases (95%). There was no significant difference in the relative distribution of body weight between hospital survivors and non-survivors, nor in cardioverter defibrillator implantation rates. Mean follow-up was 5.8±4.4 years; 5-year survival was 80±5%, lower among underweight and normal compared with heavier individuals. The 5-year survival free of implantable cardioverter defibrillator shocks was 61±7%, with no weight-based difference in shocks. Conclusion: There was no apparent weight-based influence on resuscitation survival after ventricular fibrillation in out-of-hospital cardiac arrest. People of normal or low weight had a lower long-term survival and represent at population high risk from primarily non-cardiac diseases. [Copyright &y& Elsevier]

Despite percutaneous intervention after an acute coronary syndrome, patients remain at high risk for recurrent events in the first year. Prior studies have shown that a plaque rupture can occur not only at a single culprit lesion site but also in other atherosclerotic plaques throughout the coronary vasculature in patients with stable angina, silent myocardial ischemia, and during acute coronary syndromes. A 71-year-old man who presented with exertional angina and who had a successful stent in a culprit right coronary artery is described in this article. After 4 weeks, he represented with accelerated angina. A prior lesion in the obtuse marginal artery remote from the site of the index lesion, had progressed from a 30% to 90% stenosis. This case report demonstrates the systemic nature of acute coronary syndromes, highlights the inherent instability of coronary artery disease, and sup- ports the notion of aggressive secondary prevention in these patients. [ABSTRACT FROM AUTHOR]

Atrial fibrillation (AF) is the most common rhythm disturbance seen in clinical practice. Evidence emerged that suggested inflammation was associated with risk of AF. Helicobacter pylori causes gastric and esophageal inflammation, as well as systemic and vascular inflammation. These local and systemic inflammatory effects may increase the risk of AF. Study patients were consecutive patients who underwent angiography for suspicion of coronary artery disease. Patients’ AF status was determined by a search of hospital discharge summaries for diagnostic International Classification of Diseases, Ninth Revision codes for AF, assessment of previous electrocardiograms at the index and previous admissions to LDS Hospital (Salt Lake City, Utah), and search of the electrocardiographic database of LDS Hospital. In addition to routine laboratory studies, serum was analyzed to determine H pylori serostatus and index C-reactive protein (CRP) level. A total of 943 patients with known AF status were studied. Those with AF tended to be older (70.9 ± 9.5 vs 63.9 ± 10.7 years; p <0.001) and had a higher prevalence of congestive heart failure (28% vs 11%; p <0.001). In addition, patients with AF were more likely to be seropositive for H pylori in comparison to the seronegative group (65% vs 55%; p = 0.049). Mean CRP was similar between those with and without AF (2.2 ± 2.7 vs 2.3 ± 2.4 mg/dl; p = 0.79). There was no apparent association between H pylori serostatus and CRP. Multivariate predictors of AF included age (hazard ratio [HR] 1.07 per year, 95% confidence interval [CI] 1.04 to 1.10, p <0.0001) and heart failure (HR 2.87, 95% CI 1.59 to 5.18, p <0.0001). H pylori added to the model was marginally associated with AF (HR 1.53, 95% CI 0.95 to 2.47, p = 0.08) when not accounting for age. However, younger patients (<50 years) who were H pylori seropositive had a higher relative risk of AF (8%) versus those who were seronegative (0%). In comparison, older patients seropositive for H pylori had only a modest increased risk of AF (17.5% vs 15.4%; p = 0.11). In conclusion, these data showed a general association of H pylori and AF in patients with multiple cardiovascular risk factors. The association did not persist after accounting for other risk factors. Although older age was highly associated with AF risk in this population, H pylori was additive across 3 distinct age groups, with the highest risk conveyed in the younger cohort. [Copyright &y& Elsevier]

Hypertrophic cardiomyopathy (HC) often presents with exercise-induced symptoms, including arrhythmias and sudden death. The investigators prospectively studied whether exercise testing is associated with immediate complications and if stress-induced arrhythmias and echocardiographic variables are associated with long-term adverse outcomes. Exercise echocardiography with 6-channel continuous monitoring for arrhythmias was performed in consecutive patients with HC clinically referred for the test. End points included death, myocardial infarction, revascularization, stroke, atrial fibrillation, ventricular tachycardia, and myectomy. Of 86 patients with HC (mean age 56.6 ± 16.1 years) who underwent exercise echocardiography, arrhythmias occurred in 39 (45%), including 23 (27%) with premature atrial contractions, 2 (2%) with atrial fibrillation, 28 (33%) with premature ventricular contractions (16 also had atrial arrhythmias), and 1 (1.2%) with nonsustained ventricular tachycardia (hemodynamically stable). During a follow-up of 2.6 ± 2.8 years, major events occurred in 11 patients (3 deaths, 5 revascularizations, 3 strokes). In addition, 12 patients developed atrial fibrillation, 6 developed nonsustained ventricular tachycardia, and 13 underwent myectomies. Variables associated with major events included hypertension, male gender, and worsening wall motion score index with exercise; increased exercise duration was associated with fewer events. ST-T changes on baseline electrocardiography and premature ventricular contractions were associated with atrial fibrillation risk. In conclusion, in this cohort of patients with HC, exercise testing was safe. Test results were associated with risk for adverse events. [Copyright &y& Elsevier]

Although ventricular fibrillation (VF) out-of-hospital cardiac arrest (OHCA) occurs primarily in the setting of severe ischemic heart disease (IHD), a significant proportion of events occurs in patients who do not have severe IHD. The relative effect of IHD on survival after VF OHCA is unknown. All residents of Rochester, Minnesota, who presented with a VF OHCA from November 1990 to December 2004, treated by emergency medical services, were included in the study. During the study, emergency medical services treated 208 patients (64.1 ± 13.6 years of age) for VF OHCA, with an average call-to-shock time of 6.3 ± 1.8 minutes. Of these patients, 156 had IHD and 39 had non-IHD. In 13, the underlying heart disease was unknown. Eighty-seven patients (41.8%) survived to hospital discharge with neurologic recovery (66 with IDH [42%] vs 21 with non-IHD [54%], p = 0.211)]. Five-year survival was 79 ± 6% for patients with IHD versus 100% for those with non-IHD (p = 0.047). After adjustment for other patient characteristics, IHD was not predictive of 5-year survival (hazard ratio [HR] 2.2, 95% confidence interval [CI] 0.7 to 9.8, p = 0.177). Variables associated with poor outcomes included age >65 years (HR 4.9, 95% CI 2.0 to 13.4, p = 0.0003), ejection fraction <0.35% (HR 3.0, 95% CI 1.3 to 7.3, p = 0.012), and hypertension (HR 4.9, 95% CI 1.4 to 16.3, p = 0.001). In patients with IHD, use of an implantable cardioverter-defibrillator (HR 0.32, 95% CI 0.16 to 0.88, p = 0.024) and statin therapy (HR 0.68, 95% CI 0.17 to 0.73, p = 0.001) were associated with decreased mortality. In conclusion, compared with patients with non-IHD, those with IHD had similar short- and long-term survival rates. Long-term survival in patients with IHD was primarily influenced by other co-morbid conditions. Nonetheless, in patients with IHD, use of an implantable cardioverter-defibrillator and statin therapy were associated with higher long-term survival rates. [Copyright &y& Elsevier]

Background: Left atrial catheter ablation (LACA) has emerged as a successful method to eliminate atrial fibrillation (AF). Recent reports have described atrio-esophageal fistulas, often resulting in death, from this procedure. Temporary esophageal stenting is an established therapy for malignant esophageal disease. We describe the first case of successful temporary esophageal stenting for an esophageal perforation following LACA. Case: A 48-year-old man with symptomatic drug refractory lone AF underwent an uneventful LACA. Fifty-nine ablations with an 8-mm tip ablation catheter (30 seconds, 70 Watts, 55°C), as guided by 3-D NavX™ mapping, were performed in the left atrium to isolate the pulmonary veins as well as a left atrial flutter and roof ablation line. In addition, complex atrial electrograms in AF and sites of vagal innervation were ablated. Two weeks later, he presented with sub-sternal chest pain, fever, and dysphagia. A chest CT showed a 3-mm esophageal perforation at the level of the left atrium with mediastinal soiling and no pericardial effusion. An urgent upper endoscopy with placement of a PolyFlex removable esophageal stent to seal off the esophago-mediastinal fistula was performed. After 3 weeks of i.v. antibiotics, naso-jejunal tube feedings, and esophageal stenting, the perforation resolved and the stent was removed. Over 18 months of follow-up, there have been no other complications, and he has returned to a physically active life and remains free from AF on previously ineffective anti-arrhythmic drugs. Conclusion: Early diagnosis of esophageal perforations following LACA may allow temporary esophageal stenting with successful esophageal healing. Prompt chest CT scans with oral and i.v. contrast should be considered in any patient with sub-sternal chest pain or dysphagia following LACA. [ABSTRACT FROM AUTHOR]

Background: Atrial rhythm disturbances, in particular atrial fibrillation (AF) and flutter (AFL), are common in the denervated transplanted heart. However, there is a relative paucity of data in the prevalence, mechanism of arrhythmia, and long-term significance. Objectives: (1) Determine the prevalence of AF and AFL in heart transplant patients, (2) define the echo/Doppler features associated with arrhythmia, and (3) evaluate the impact of arrhythmia on long-term survival. Methods: All patients who received an orthotopic heart transplant at the Mayo Clinic, Rochester, Minnesota, between 1988 and 2000 were included. Analysis of serial electrocardiograms and Holter monitor records provided evidence of AF or AFL development. Variables including general patient demographics, histology-proven rejection numbers and grades, results of serial coronary angiography, endomyocardial biopsy specimens, and echocardiographic studies performed at 6 weeks and 3 years after transplant were obtained to determine variables predictive of arrhythmia development. Results: There were 167 heart transplant recipients, of which 16 (9.5%) developed AF and another 25 (15.0%) developed AFL over 6.5 ± 3.4 years. Patients who developed AF or AFL had lower left ventricular (LV) ejection fractions (56.6% ± 1.6% vs 62.5% ± 1.5%, p < 0.05), higher LV end-systolic dimensions (LVESD) (33.6 ± 1.12 mm vs 29.7 ± 0.97 mm, p < 0.01), higher right atrial volume indexes (43.2 ± 12.3 ml vs 35 ± 5.3 ml, p < 0.03), lower mitral deceleration time (145 ± 8 msec vs 160 ± 12 msec, p < 0.05), and lower late mitral annulus tissue a′ velocities (0.06 ± 0.005 cm/sec vs 0.08 ± 0.01 cm/sec, p < 0.02) compared with an age- and gender-matched Sinus Rhythm Group. Grade 3 rejection was a time-dependent covariate predictor of AFL risk (hazard ratio [HR], 2.95; 95% confidence interval [CI], 1.3–6.6, p < 0.008) but not AF (HR, 2.264; 95% CI, 0.72–7.1; p = 0.10). Thirty-nine of 167 patients died: 13 in the arrhythmia group and 26 in the normal sinus rhythm group. Development of atrial dysrhythmia adversely affected the outcome in the first 5 years (p < 0.001) compared with normal sinus rhythm. Predictors of long-term mortality included AF/AFL (HR, 2.88; 95% CI, 1.38–5.96; p < 0.004), age at transplant (HR, 1.04; 95% CI, 1.00–1.07, p < 0.03), coronary artery disease (HR, 2.655; 95% CI, 1.25–5.64; p = 0.01), pre-transplant cardiac amyloidosis (HR, 5.02; 95% CI 2.37–10.62; p < 0.001), right atrial volume index (HR, 1.03; 95% CI, 1.00–10.7; p = 0.03), mitral deceleration time <160 msec (p < 0.01), and LVESD >30 mm (p < 0.04). Conclusion: Development of AF/AFL post-heart transplantation is not uncommon and is associated with decreased long-term survival. Cumulative effects of repeated moderate-to-severe (grade 3 or more) rejections that result in increased cardiac fibrosis are associated with the development of AFL, but not AF. Similarly advanced restrictive diastolic dysfunction caused by fibrosis from repeated moderate-to-severe (grade 3 or more) rejections was predominant in the patients with arrhythmia and was a marker of poor long-term outcome. [Copyright &y& Elsevier]

Background: The phrenic nerve can be injured with radiofrequency energy delivery. Nevertheless, the mechanisms of injury are unknown. This study was undertaken to examine phrenic nerve tissue temperatures during ablation at the pulmonary vein (PV) orifice, assess the temperature dependence of injury, and to delineate the possible mechanisms of untoward nerve effects. Methods: Ten dogs underwent ablation at the right superior PV (RSPV) orifice. Phrenic nerve temperatures were assessed with implanted thermocouples overlying the endocardial ablation site. Using an 8-mm ablation catheter tip, energy was titrated to 50°C and incremented by 5°C for 120 seconds. Results: Phrenic nerve capture was achieved in nine (90%) dogs after thermocouple implantation. A RSPV orifice tissue temperature >60°C occurred in 32 (84%) of energy deliveries with a power of 34 ± 22 W. In three (33%) dogs, this resulted in nerve dysfunction (maximum nerve temperature: 41°C, 41°C, and 91°C) with histology consistent with acute thermal injury. In four additional dogs, 17 energy deliveries were made directly to the phrenic nerve using a novel in situ model. In 5 (29%) energy deliveries, nerve function was impacted immediately by the generated current, with resolution simultaneous with discontinuing radiofrequency. Transient phrenic nerve injury occurred in all dogs at a temperature of 47 ± 3°C (range: 43–53°C) after 38 ± 32 seconds (range: 20–120 seconds). After termination of the energy delivery, nerve function returned in 15(88%) during 30 seconds of postablation pacing. In two (12%) ablation attempts, nerve recovery was delayed (>3 minutes). Permanent injury occurred in all dogs after 92 ± 83 seconds (range: 20–280 seconds) of additional energy delivery at a temperature of 51 ± 6°C (range: 45–65°C). Conclusion: Phrenic nerve injury can be more common than anticipated with RF ablation at the RSPV orifice. Relatively low tissue temperatures can injure the nerve. Immediate nerve effects suggest a second mechanism of nerve dysfunction related to electrical current. Transient nerve effects occur prior to permanent damage, providing an opportunity to discontinue energy delivery before permanent injury. [ABSTRACT FROM AUTHOR]

Objectives: We sought to evaluate the efficacy and safety of a novel cryothermal balloon ablation system in creating pulmonary vein (PV) isolation. Background: Pulmonary vein isolation using standard radiofrequency ablation techniques is limited by procedure-related complications, such as thrombus formation and PV stenosis. Cryothermal ablation may reduce the risk of such complications. Methods: Eight dogs underwent circumferential ablation of both superior PVs for either 4 or 8 min using a cryothermal balloon catheter (CryoCath Technologies Inc., Kirkland, Canada). Both fluoroscopy and intracardiac ultrasound (ICE)-guided balloon and Lasso catheter positioning at the PV ostia assessed short-term PV integrity. In six additional dogs, long-term PV integrity was assessed by computed tomography at 16 weeks after ablation. Results: Successful electrical isolation was achieved acutely in 14 of 16 (87.5%) PVs and was confirmed in one-week survival studies in 10 of 12 (83%) PVs. Successful isolation was higher in the absence of any peri-balloon flow leak as seen by ICE (p = 0.015), and with balloon temperatures ≤−80°C (p = 0.015). Cryolesions were located at the veno-atrial junction and were homogeneous, with intact endothelium and free of thrombus formation. Although limited angiographic PV narrowing was noted in the early follow-up period, no significant PV narrowing was seen long-term. Right phrenic nerve injury was seen in 50% of the animals studied at one week. Conclusions: This novel cryothermal balloon ablation system is effective for isolating PVs, but injury to the right phrenic nerve was noted in this early experience. Further studies are needed to assess the long-term efficacy and safety of this technique. [Copyright &y& Elsevier]

Background: Perforation during catheter procedures in either the atrium or ventricle is relatively uncommon, but potentially fatal if tamponade ensues. This study analyzes the occurrence and outcomes of cardiac perforation during catheter-based radiofrequency ablation procedures in the left atrium. Methods: All patients with a periprocedure perforation who have undergone radiofrequency ablation for atrial fibrillation (AF) or tachycardia were included. Results: Of 632 procedures performed from January 1999 to October 2004, 15 (2.4%) were complicated by perforation requiring pericardiocentesis. The perforation site was left atrium in 9 (60.0%), right atrium in 1 (6.7%), and right ventricle in 5 (33.3%). Intracardiac echocardiography was used in 13 (86.7%) and revealed an effusion before overt instability in 11 (73.3%). Thirteen (86.7%) patients developed a blood pressure <60 mmHg. The pressure stabilized in all patients after pericardiocentesis (hypotension to intervention: 10.1 ± 5.1 minutes). The total blood volume removed was 848 ± 880 mL (left atrium/right atrium: 1,074 ± 1,002 vs right ventricle: 396 ± 266, P = 0.168). Two patients required surgery to close left atrium dome perforations. The ablation was completed in 7 (46.7%) patients. Ten (66.7%) later developed early reoccurrence of AF. All patients were neurologically intact at hospital discharge. During a 1.5 ± 1.1 year follow-up, AF was eliminated (n = 4) or controlled (n = 1) in 5 (71.4%) patients with complete procedures, and 2 (20.0%) patients underwent successful repeat ablation. Conclusion: The incidence of perforation during ablation of the left atrium is low. Most perforations occur in the left atrium; however, few require surgical closure. Although less than with uncomplicated procedures, the majority of patients with complete ablations achieve long-term elimination of AF. [ABSTRACT FROM AUTHOR]

Abstract: Background:: The incidence of ventricular fibrillation (VF) out-of-hospital cardiac arrest (OHCA) treated by first responders has declined over the past decade. Since VF OHCA occurs primarily in the setting of severe coronary artery disease, primary and secondary prevention strategies may in part account for the decline. However, such strategies may not have a similar impact on non-ischemic arrest. Methods:: All Rochester Minnesota residents who presented with a VF OHCA from 1991 to 2004, treated by emergency medical services (EMS), were included in the study. Incidence rates were calculated based on the population for Rochester during the time period. Changes over time were tested using Poisson regression models. The significance of the trends was estimated according to the Mantel–Haenszel test for association, and two-tailed p-values reported. Results:: The overall incidence of EMS-treated VF OHCA in Rochester during the study period was 10.6 per 100,000 (95% CI 9.1–11.8). The incidence decreased significantly (p <0.001) over the study period [1991–1994: 18.2/100,000 (95% CI 13.4–21.9); 1995–1999: 11.8/100,000 (95% CI 10.4–17.9); 2000–2004: 8.7/100,000 (95% CI 6.0–13.0)]. The incidence of VF OHCA with ischemic heart disease also declined [1991–1994: 13.4/100,000 (95% CI 8.9–16.9); 1995–1999: 11.1/100,000 (95% CI 8.2–15.9); 2000–2004: 5.5/100,000 (95% CI 3.8–8.2), p <0.001]. In contrast, the incidence VF OHCA with non-ischemic heart disease increased [1991–1994: 2.1/100,000 (95% CI 1.13–3.1); 1995–1999: 2.3/100,000 (95% CI 1.9–3.7); 2000–2004: 2.9/100,000 (95% CI 2.0–3.4), p <0.001]. Conclusion:: The incidence of VF OHCA is declining. The decline is attributable to the reduction of VF cardiac arrest with ischemic heart disease; suggesting an impact of treatment strategies targeted at coronary artery disease. The relative increasing incidence of non-ischemic VF OHCA suggests that more efforts are required to minimize mortality in this cohort population. [Copyright &y& Elsevier]

Coronary heart disease is the most common cause of death in the United States, with ventricular fibrillation (VF) the most common initial rhythm when cardiac disease causes arrest. Survival after VF out-of-hospital cardiac arrest (OHCA) depends on a sequence of events called the chain of survival, which includes rapid access to emergency medical services, cardiopulmonary resuscitation, defibrillation, and advanced care. Because of widespread implementation of defibrillation programs, more patients survive VF OHCAs, making subsequent care of these patients important. Early hospitalization must focus on potential neurologic injury and therapy targeted at the underlying cardiac disease and antiarrhythmic therapy for long-term secondary prevention of sudden death. Attention to certain cohorts who are at high risk despite their underlying disease, such as women and elderly patients, is necessary. These cohorts may have the greatest response to short-term and long-term therapies for cardiac rehabilitation. With these approaches, long-term survival and quality of life after VF OHCA are favorable. Broadening the focus of the chain of survival to include in-hospital and long-term care will further Improve favorable outcomes achieved in an early defibrillation program. [ABSTRACT FROM AUTHOR]

Abstract: Background:: In November 1990, a 2-year trial period was initiated in which police officers in the city of Rochester, Minnesota, were trained in the operation of automated external defibrillators (AEDs). Following the trial, the program was expanded as the city grew in population and area. In 1998 firefighters also were equipped with AEDs, bringing to a total 18 AEDs with police and fire personnel, in addition to paramedic capability. Methods:: From November 1990 to December 2003, all adult patients with atraumatic cardiac arrest with ventricular fibrillation (VF) as the presenting rhythm were included for analysis. Call-to-shock time intervals, restoration of spontaneous circulation after defibrillation shocks only (without need for vasoactive or inotropic drug administration), and neurologically intact survival (overall performance category (OPC) 1 or 2) were study end-points. Results:: One hundred and ninety-three patients presented in VF. Of these, 80 (41%) were discharged neurologically intact. Of the 159 VF patients whose arrest was bystander-witnessed 73 (46%) were discharged. Survival from non-VF arrest was very low (5%). Assessment of VF survivors demonstrated a quality of life, adjusted for age, gender, and disease, similar to that of the general population. Conclusions:: These data demonstrate that a relatively high survival can be obtained in a city of this size and area employing a non-tiered community-wide approach within the emergency medical services (EMS) system. [Copyright &y& Elsevier]

Abstract: Introduction:: Previous studies have shown that early defibrillation programs improve survival after an out-of-hospital cardiac arrest (OHCA). Reports also suggest that women fare worse than men do after cardiovascular events, but there is no population-based study of sex differences after an OHCA with early defibrillation. We, therefore, compared the short- and long-term survival and quality-of-life (QOL) in women and men after an OHCA. Methods:: All patients with a ventricular fibrillation (VF) OHCA who received early defibrillation in Olmstead County, Minnesota between November 1990 and December 2000 were included. Using medical records and the cardiac arrest database, the short- and long-term survival and QOL based on a SF-36 survey of each sex were compared. Adjusted QOL scores were obtained by using age- and sex-specific norms from a sample of the general U.S. population; an adjusted score of 50 (normalized mean) was considered normal. Results:: Thirty-seven female and 163 male patients presented with a VF OHCA and early defibrillation. Survival to hospital admission was significantly better for women than men [30 female survivors to admission (81%), 112 male (69%), p =0.04]. Paradoxically, survival to discharge among those admitted was worse for women [13 female survivors to discharge (43%), 66 male (61%), p =0.04]. The average length of follow-up was 4.8±3.0 years. The 5-year expected survival was 83% in women and 78% in men (p =0.48). There was no difference in call-to-shock time (6±2, 6±2min, p =0.6) or whether the arrest was witnessed (86, 82%, p =0.64). There was no statistical difference between women and men in age (64±17, 65±14 years), ejection fraction (40±17, 40±18%), diabetes (17, 29%, p =0.16), hypertension (23, 28%, p =0.58) or known CAD (27, 48%, p =0.06). Adjusted QOL scores were similar between women and men in terms of pain (52±9, 52±10) vitality (47±11, 40±9), general health (49±9, 44±7), social function (51±10, 51±8), and mental health (50±10, 49±6). Conclusion:: Women are more likely to survive to hospital admission following an OHCA. However, admitted women less likely to survive their hospital stay. Long-term survival and QOL are equally favorable in both sexes. [Copyright &y& Elsevier]

Beta-blocker therapy has been shown to benefit patients who have coronary artery disease and present with acute myocardial infarction (AMI) and/or congestive heart failure (HF). However, whether β-blocker therapy provides a similar benefit in patients who have coronary artery disease but not AMI or HF is unknown. A population of 4,304 patients who did not have HF but did have angiographically confirmed coronary artery disease (≥1 stenosis of ≥70%) without AMI at hospital presentation was evaluated. Baseline demographics, cardiac risk factors, clinical presentation, therapeutic procedures, and discharge medications were recorded. Patients were followed for a mean of 3.0 ± 1.9 years (range 1 month to 6.9 years) for outcomes of all-cause death or AMI. Patients'' average age was 65 ± 11 years and 77% were men. Overall, 10% died and 5% had a nonfatal AMI. Discharge β-blocker prescription was associated with an increased event-free AMI survival rate for all-cause death (no β blocker 88.3%, β blocker 94.5%, p &#60;0.001) and death/AMI (no β blocker 83.4%, β blocker 89.2%, p &#60;0.001) but not non-fatal AMI (no β blocker 93.6%, β blocker 94.1%, p = 0.60). After adjustment for 16 covariates, including statin prescription, angiotensin-converting enzyme inhibitor prescription, and type of baseline therapy, the effect of β blockers on the combination end point of death/AMI was eliminated. However, the effect of β blockers on death remained (hazard ratio 0.66, 95% confidence interval 0.47 to 0.93, p = 0.02). Thus, β blockers are clearly indicated for most patients who have HF or AMI, and our results suggest that patients who have coronary artery disease without these conditions have approximately the same protective benefit against death. No effect was observed on longitudinal incidence of AMI or the combination of death/nonfatal MI. [Copyright &y& Elsevier]

Background: Programs focusing on early defibrillation have improved both short- and long-term survival of patients with VF out-of-hospital cardiac arrest (OHCA). Subsequent long-term management of survivors would be facilitated by a straight-forward, non-invasive method of identifying those at highest risk for recurrence. Therefore, we assessed the predictive value of the standard ECG to determine both short- and long-term outcomes in survivors of VF OHCA to assist in risk stratification of those patients at highest risk of sudden death. Methods: All patients with an OHCA between November 1990 and December 2000 who received early defibrillation for VF in Olmsted County Minnesota (MN) were included. Cox proportional hazards modeling was used to examine ECG variables and subsequent ICD deployment and death. Results: Two hundred patients presented in VF OHCA; of these 138 (69%) survived to hospital admission (seven died in the emergency department prior to admission) and 79 (40%) were discharged. The QRS duration (141 ± 41 ms in nonsurvivors, 123 ± 35 in survivors, P = 0.004) was predictive of short-term mortality in patients who did not survive to hospital discharge. The ventricular rate, PR interval, presence of right or left bundle branch block, QTc, ST elevation myocardial infarction, and atrial fibrillation/flutter were nonpredictive. The average length of follow up for hospital dismissal survivors was 4.8 ± 3.0 years. In univariate analysis, each 30 ms interval increase in the QRS width and PR interval was associated with increased mortality and ICD deployment hazard ratio of 1.6 (CI 1.1–2.5, P = 0.02) and 1.12 (CI 1.0–1.2, P = 0.05), respectively. In multivariate analysis accounting for admission ejection fraction, a PR > 200 ms [HR 4.5 (CI 1.7–11.8, P = 0.022)], QRS width increase greater than 30 ms [HR 1.9 (CI 1.3–2.8, P < 0.001)], and a QRS > 120 ms [HR 2.4 (CI 1.1–5.4, P = 0.032)] were predictive of long-term mortality and ICD shocks. Conclusion: Careful evaluation of the admitting and discharge ECG provides prognostic information for in-hospital and long-term outcomes, respectively in this cohort of out-of-hospital cardiac arrest survivors. The QRS duration on the dismissal ECG following VF OHCA provides prognostic information which might be useful to identify those at highest risk long-term, and who would benefit from more aggressive antiarrhythmic therapy and cardiac stabilization. [Copyright &y& Elsevier]

• Objective: To describe and evaluate the in-hospital treatment of ventricular arrhythmias and underlying structural heart disease in patients who survive ventricular fibrillation (VF) out-of-hospital cardiac arrest (OHCA) in a region with a high survival rate after hospital discharge. • Patients and Methods: The study included all patients presenting in Olmsted County, Minnesota, who had experienced OHCA between November 1990 and December 2000 and who underwent defibrillation of VF by an emergency medical service system. • Results: Of 200 patients who experienced VF arrest, 138 (69%) survived to hospital admission (7 died in the emergency department before admission), and 79 (40%) were discharged. Of patients who were discharge, 37 (47%) had a reversible cause of the arrest (perimyocardial infarction) and received treatment of the primary process. The other 42 patients who were discharged had ischemic coronary heart disease (CHD) (n=25), nonischemic CHD (n=10), or idiopathic VF (n=7). Four of the patients with CHD but no left ventricular dysfunction were treated with coronary artery bypass grafting or percutaneous coronary intervention alone. A total of 52 patients (66%) were candidates for electrophysiologic testing. Of these patients, 48 (92%) underwent electrophysiologic testing; of these patients, 10 received amiodarone alone, and 35 received an implantable cardioverter-defibrillator (ICD) (of whom 3 also received amiodarone). Patients who did not receive ICD therapy typically presented before 1998 with CHD and underwent coronary artery bypass grafting or percutaneous coronary intervention only. Of 79 patients who were discharged, 14 (18%) with an ICD have received subsequent shocks. Nineteen (24%) of 79 patients have died, 5 of a primary cardiac etiology (including 2 with repeated OHCA). • Conclusions: The VF OHCA survival rate is high in the setting of rapid defibrillation, with 40% of patients being discharged from the hospital. By the end of the 10-year study, more patients were receiving antiarrhythmic therapy, in particular ICD implantation, after hospital admission. Overall, the long-term survival in patients with VF OHCA is favorable. [ABSTRACT FROM AUTHOR]

In this study of a unique cohort of out-of-hospital cardiac arrest survivors with ventricular fibrillation, the initial ejection fraction was predictive of increased long-term mortality. However, overall long-term quality-of-life was favorable and independent of the ejection fraction. [Copyright &y& Elsevier]

: ObjectivesThe purpose of the study was to determine if atrial ectopy (AE) or atrial arrhythmias during exercise are predictive of an increased risk of cardiac events and death.: BackgroundAlthough stress-induced atrial arrhythmias are common during exercise testing, there is a paucity of data regarding the correlation with underlying heart disease and cardiovascular outcomes. Atrial arrhythmias may reflect underlying left atrial enlargement and diastolic dysfunction, which are prognostic of mortality. We hypothesized that these stress-induced arrhythmias are associated with long-term adverse cardiac events.: MethodsExercise echocardiography was performed in 5,375 patients (age 61 ± 12 years) with known or suspected coronary artery disease. An abnormal result was defined as exercise-induced atrial fibrillation (AF)/atrial flutter, supraventricular tachycardia (SVT), or AE.: ResultsA total of 311 (5.8%) patients died (132 [2.5%] from cardiac causes) over a period of 3.1 ± 1.7 years. In addition, 193 (3.6%) patients experienced a myocardial infarction (MI) and 531 (9.9%) patients required revascularization. During exercise testing, 1,272 (24%) patients developed AE, 185 (3.4%) developed SVT, and 43 (0.8%) developed AF. The five-year cardiac death rate was not statistically different between groups (none [3.8%], AE [4.3%], SVT [3.7%], AF [0%], p = 0.43). The five-year rate of MI was significantly different between groups (none [5.7%], AE [8.3%], SVT [0%], AF [9.0%], p = 0.005). The five-year rate of revascularization between groups was not significantly different (none [14.2%], AE [17.0%], SVT [11.8%], AF [14.8%], p = 0.50). A composite of all five-year adverse end points was similar between groups (none [22.7%], AE [27.8%], SVT [17.7%], AF [25.7%], p = 0.10). In stepwise multivariate analysis, AE was not predictive of myocardial infarction when taking into account traditional clinical variables and exercise test results.: ConclusionsIn this large cohort of patients, the occurrence of AE was predictive of an increased risk of MI. However, the association did not persist after adjustment for clinical and exercise variables known to predict adverse long-term cardiovascular outcomes. The rate of long-term cardiac death or revascularization was not influenced by the development of stress-induced atrial arrhythmias. [Copyright &y& Elsevier]

Several factors are responsible for the occurrence of cardiac complications after bone marrow transplantation (BMT). These factors include the cardiotoxic effects of radiation therapy, antineoplastic and immunosuppressive drugs, abnormal immunologic reactions associated with graft-vs-host disease, and infectious agents. We report the case of a 45-year-old woman with T-cell prolymphocytic leukemia and no prior risk factors for coronary artery disease in whom sudden cardiac death occurred 2½ years after allogeneic BMT from an unrelated male donor. Autopsy revealed severe 3-vessel coronary disease with grade 4/4 stenosis. This process was primarily nonatherosclerotic, with intimal hyperplasia of undetermined etiology. Furthermore, fluorescence in situ hybridization to identify the donor Y chromosome with simultaneous immunofluorescence labeling of smooth muscle actin suggested the presence of donor cells that transformed into myocytes. Coronary artery disease is an important, albeit tare,complication of BMT. Donor hematopoietic cells may contribute to its pathogenesis. [ABSTRACT FROM AUTHOR]

Background: Brain injury after a cardiac arrest remains a major cause of morbidity. Programs focusing on early defibrillation have yielded improved survival of patients after hospital discharge following ventricular fibrillation (VF) out-of-hospital cardiac arrest (OHCA). Early defibrillation that promptly restores a circulating rhythm should decrease the hypoxic period and subsequent organ injury. Therefore this study was designed to determine if long-term memory complaints persist in VF OHCA survivors resuscitated in an early defibrillation program when compared with a healthy control population not experiencing cardiac arrest. Methods: All patients with an OHCA between November 1990 and January 2001 who received defibrillation by emergency medical services personnel in Olmsted County, MN, USA, were included. The memory function questionnaire (MFQ), a 64-item, 7-point Likert-scaled instrument to evaluate the perception of everyday memory functioning was sent to all survivors. The MFQ comprises four scales: general frequency of forgetting (rates general forgetting), retrospective functioning (compares current memory with past ability), seriousness of forgetting (rates how memory impairment impacts daily life), and mnemonics usage (measures adaptation). The MFQ is scaled so that high scores reflect less severe memory complaints. The comparison population comprised members of the Mayo Older Americans Normative Studies (MOANS) cohort. Quality of life was ascertained with a short form (SF)-36 survey. Results: Seventy-nine of the 200 VF OHCA patients (40%) were discharged. Twenty-two patients have died since dismissal, with an overall average length of follow-up of 4.9±3.0 years. Thirty-eight (67%) of the survivors completed the MFQ. Compared with the normal, there was a significant decrease in the general frequency of forgetting score of 144.2±37.4 versus 168.1±27.3 (P<0.001) and the seriousness of forgetting score of 84.8±26.7 versus 95.2±19.7 (P=0.004). The retrospective function-scale scores were not significantly different (18.4±6.8 versus 18.7±5.0 (P=0.74)). Younger patients (lesser than 65 years of age) reported an increase in general forgetting and the seriousness of forgetting compared with older survivors. A comparison with SF-36 scores suggested an association between general forgetting and decreased vitality (P=0.03) and the seriousness of forgetting with a decreased general health (P=0.005), mental health (P=0.009), physical functioning (P=0.02), and vitality (P=0.05). Conclusion: In a cohort of VF OHCA patients, survivors report more memory complaints in comparison with a general healthy older population. There were more long-term-memory complaints in younger patients. Patients with higher long-term quality-of-life score have fewer memory complaints. [Copyright &y& Elsevier]

A patent foramen ovale (PFO) is a frequent remnant of embryological development with clinical importance in thromboembolism, paradoxical embolism, stroke, platypneaorthodeoxia, decompression sickness, and migraine headache. The proposed mechanisms of stroke with PFO include paradoxical embolization, in situ thrombosis within the canal of the PFO, associated atrial arrhythmias, and concomitant hypercoagulable states. Prospective trials using aspirin treatment to reduce recurrent stroke showed a significant recurrence of neurologic events in patients with a PFO and atrial septal aneurysm. Use of warfarin anticoagulation does not further reduce recurrent stroke rates compared with antiplatelet therapy. Both surgical and catheter-based modes of closure have been shown to decrease the rate of subsequent embolic events substantially. Successful closure, defined by transesophageal echocardiography, appears to predict freedom from subsequent embolic events. To our knowledge, no randomized trials comparing anticoagulation with surgical or catheter-based closure have been performed. [ABSTRACT FROM AUTHOR]

Atherosclerosis is the major cause of adult mortality in the developed world, and a significant contributor to atherosclerotic plaque progression involves smooth muscle cell recruitment to the intima of the vessel wall. Controversy currently exists on the exact origin of these recruited cells. Here we use sex-mismatched bone marrow transplant subjects to show that smooth muscle cells throughout the atherosclerotic vessel wall can derive from donor bone marrow. We demonstrate extensive recruitment of these cells in diseased compared with undiseased segments and exclude cellcell fusion events as a cause for this enrichment. These data have broad implications for our understanding of the cellular components of human atherosclerotic plaque and provide a potentially novel target for future diagnostic and therapeutic strategies. [ABSTRACT FROM AUTHOR]

Describes a novel presentation of tetanus and to review the course of the respiratory component and treatment and management of the disease using the case of a patient presented with persistent hiccups, dyspnea, and pleurisy of three days duration caused by tetanus from inadequate secondary immunity. Clinical presentation; Tests performed; Treatment and monitoring.