Impact of Heated Tobacco Products, E-Cigarettes, and Cigarettes on Inflammation and Endothelial Dysfunction.

In addition to the market launch of heated tobacco products (HTPs) and the JUUL as well as the EVALI, they caused a widespread discussion on the risk reduction compared to a combustible cigarette. Furthermore, first data showed harmful effects on the cardiovascular system. We, therefore, conducted investigations including a control group with a nicotine-free liquid. Forty active smokers were studied in two different approaches during and after consuming an HTP, a cigarette, a JUUL, or a typical electronic cigarette with or without nicotine in a partly double-blinded randomised, cross-over trial. Inflammation, endothelial dysfunction, and blood samples (full blood count, ELISA, multiplex immunoassay) were analysed, and arterial stiffness was measured. In addition to the cigarette, an increase in the white blood cell count but also in proinflammatory cytokines was shown for the various nicotine delivery systems. These correlated with the parameters of arterial vascular stiffness as a clinical parameter of endothelial dysfunction. It can be shown that even a single consumption of the different nicotine delivery system or cigarette leads to a significant inflammatory reaction followed by endothelial dysfunction and increased arterial stiffness causing cardiovascular disease. Inflammation, endothelial dysfunction, and arterial stiffness should be addressed in long-term observational studies.

Stand-alone Focal Impulse and Rotor Modulation (FIRM) ablation versus second-generation cryoballoon pulmonary vein isolation for paroxysmal atrial fibrillation.

INTRODUCTION: Focal Impulse and Rotor Modulation (FIRM) guided catheter ablation aiming at stable rotors has been investigated as a treatment option in patients with atrial fibrillation (AF). The objective of this study was to compare the safety and efficacy of FIRM-guided ablation with second-generation cryoballoon pulmonary vein isolation (CB2-PVI) in paroxysmal AF. METHODS: Consecutive patients (n = 22, mean age 60 ± 11 years, 59.1% of males) who were treated with a stand-alone FIRM-guided ablation were included in this retrospective single-center study. Procedural data and arrhythmia-free survival at 12 months were compared with n = 86 consecutive patients (mean age 62 ± 13 years, 62.4% of males) who received de-novo CB2-PVI. RESULTS: Median procedure duration was significantly longer in the FIRM group than in the CB2-PVI group (152 [IQR 120-176] minutes vs. 122 [110-145] minutes; p = .031). One patient (1.2%) in the CB2-PVI group and five patients (22.7%) in the FIRM group had vascular access complications. Atrial tachyarrhythmias recurred in 15 patients in the FIRM group and 11 in the CB2-PVI group. Kaplan-Meier estimation of single-procedure arrhythmia-free survival at 12 months was 25% (95% confidence interval [CI] 6%-44%) in the FIRM group and 87% (95% CI 78%-96%) in the CB2-PVI group (p < .001). Repeat ablations were performed in 14/20 (70.0%) patients in the FIRM group and in 12/85 (14.1%) in the CB2-PVI group (p < .001). CONCLUSION: De novo ablation of AF using FIRM-guided AF ablation results in shorter arrhythmia-free survival after 12 months compared to CB2-PVI and a need for repeat ablation in the majority of patients to achieve stable sinus rhythm.

E-cigarettes and cigarettes worsen peripheral and central hemodynamics as well as arterial stiffness: A randomized, double-blinded pilot study.

The introduction of electronic cigarettes has led to widespread discussion on the cardiovascular risks compared to conventional smoking. We therefore conducted a randomized cross-over study of the acute use of three tobacco products, including a control group using a nicotine-free liquid. Fifteen active smokers were studied during and after smoking either a cigarette or an electronic cigarette with or without nicotine (eGo-T CE4 vaporizer). Subjects were blinded to the nicotine content of the electronic cigarette and were followed up for 2 hours after smoking a cigarette or vaping an electronic cigarette. Peripheral and central blood pressures as well as parameters of arterial stiffness were measured by a Mobil-O-Graph® device. The peripheral systolic blood pressure rose significantly for approximately 45 minutes after vaping nicotine-containing liquid ( p<0.05) and for approximately 15 minutes after smoking a conventional cigarette ( p<0.01), whereas nicotine-free liquids did not lead to significant changes during the first hour of follow-up. Likewise, heart rate remained elevated approximately 45 minutes after vaping an electronic cigarette with nicotine-containing liquid and over the first 30 minutes after smoking a cigarette in contrast to controls. Elevation of pulse wave velocity was independent from mean arterial pressure as well as heart rate in the electronic cigarette and cigarette groups. In this first of its kind trial, we observed changes in peripheral and central blood pressure and also in pulse wave velocity after smoking a cigarette as well as after vaping a nicotine-containing electronic cigarette. These findings may be associated with an increased long-term cardiovascular risk.

Biomarker response and therapy prediction in renal denervation therapy - the role of MR-proadrenomedullin in a multicenter approach.

BACKGROUND: Renal denervation has been proposed as a therapeutic option in patients with resistant hypertension. Circulating blood borne biomarkers might be helpful to identify individuals responding to RDN therapy. MR-proADM is a strong prognostic marker in patients with cardiovascular disease. The aim of this multicenter study was to evaluate the effect of RDN on MR-proADM concentrations. METHODS AND RESULTS: We measured MR-proADM, BNP, and MR-proANP in 110 patients before and after RDN in a multicenter setting. All patients were followed up after 1 and 6 months by office and ambulatory blood pressure (BP) measurements. The mean office BP decreased from 165/89 to 152/87 mmHg 6 months after RDN (systolic: p < 0.001; diastolic: ns), the responder-rate was 74%. Intriguingly MR-proADM concentrations increased from 0.66 to 0.69 nmol/L (p < 0.001) and were significantly associated with reduction of systolic office BP after 6 months in multivariate analyses (coefficient -0.0018, p < 0.001). In therapy-responders MR-proADM concentrations showed a significantly higher increase over time (coefficient 0.0105, p < 0.05), as compared to non-responders. There were no significant differences in BP change for individuals with low and high baseline MR-proADM (BP-Delta low MR-proADM -23/-4 mmHg vs. high MR-proADM -24/-5 mmHg). The natriuretic biomarkers BNP and MR-proANP did not change significantly after 6 months. Biomarkers at baseline were not able to predict for therapy-responder. CONCLUSION: In patients undergoing RDN, baseline measurements of various biomarkers had no prognostic use for therapy success in this short time follow-up period in a multicenter approach. Intriguingly, MR-proADM showed a significant association with BP reduction after 6 months.

Ambulatory (24 h) blood pressure and arterial stiffness measurement in Marfan syndrome patients: a case control feasibility and pilot study.

BACKGROUND: The aim of this work is the investigation of measures of ambulatory brachial and aortic blood pressure and indices of arterial stiffness and aortic wave reflection in Marfan patients. METHODS: A case-control study was conducted including patients with diagnosed Marfan syndrome following Ghent2 nosology and healthy controls matched for sex, age and daytime brachial systolic blood pressure. For each subject a 24 h ambulatory blood pressure and 24 h pulse wave analysis measurement was performed. RESULTS: All parameters showed a circadian pattern whereby pressure dipping was more pronounced in Marfan patients. During daytime only Marfan patients with aortic root surgery showed increased pulse wave velocity. In contrast, various nighttime measurements, wave reflection determinants and circadian patterns showed a significant difference. CONCLUSIONS: The findings of our study provide evidence that ambulatory measurement of arterial stiffness parameters is feasible and that these determinants are significantly different in Marfan syndrome patients compared to controls in particular at nighttime. Further investigation is therefore indicated.

Renal denervation - a clinical update and future directions.

The aim of this review is to give a contemporary update on renal denervation therapy focusing particularly on the scientific background and present literature as well as on different technical approaches and potential future directions.

Effects of Physical Activity in the High School Curriculum on Cardiovascular Health, Cognitive and Physical Performance.

Cardiovascular health at a young age has implications for preventing cardiovascular disease, and it is associated with improved physical and cognitive performance during the aging process. Sports are well known to prevent cardiovascular disease; however, school-based interventions have mostly been neglected. This cross-sectional study aimed to compare groups of high school students, stratified by the amount of physical activity in their high school curriculum and downtime. Comparisons concerning physical and cognitive performance and arterial stiffness were made. A total of 63 senior-year students were investigated. Arterial stiffness was assessed using the oscillometric technique with ArteriographTM detection. Three-kilometer and pendulum runs were conducted as typical training loads. Cognitive performance was evaluated via the visual and verbal memory and number connection tests. Regarding cognitive skills, extracurricular physical activity improved the number connection test in male participants (p = 0.004). For physical performance, female students with a sports-focused curriculum were faster in the 3 km run (p < 0.001). Concerning arterial stiffness, the measurements yielded a lower mean arterial pressure (p = 0.015) and aortic pulse wave velocity (p = 0.04) in male students with a sports-focused curriculum. In summary, extracurricular physical activity and enrollment in a sports-focused curriculum may be associated with lower cardiovascular risk due to lower arterial stiffness and better physical and cognitive abilities.

Impact of Chewing Bags, E-Cigarettes, and Combustible Cigarettes on Arterial Stiffness and Small Airway Function in Healthy Students.

Several substitute products are discussed as a healthier alternative to smoking, thereunder e-cigarettes and smokeless tobacco products, e.g., chewing bags, which are increasingly used in this context. We investigated the acute effects of chewing bags compared to combustible cigarettes and e-cigarettes with and without nicotine on small airways and arterial stiffness in a head-to-head design. This single-center, four-arm cross-overstudy included 20 healthy occasional smokers (25 ± 0.6 years). On four test days, participants consumed one product per day. Before, during, and after consumption, peripheral and central hemodynamic as well as arterial stiffness parameters were measured by Mobil-O-Graph™ (I.E.M., Germany). Resistance and small airway function were assessed by tremoFlo® c-100 (THORASYS Thoracic Medical Systems Inc.). The combustible cigarette and the e-cigarettes with and without nicotine significantly increased the resistance of the small airways (p < 0.05), while chewing bags had no effect. All nicotine containing products (e-cigarette with nicotine, combustible cigarette, chewing bag) as well as the e-cigarette without nicotine significantly increased parameters of hemodynamic and arterial stiffness. Changes in blood pressure and arterial stiffness were similar after smoking, vaping, and using chewing bags. We conclude that e-cigarettes and combustible cigarettes have similar acute harmful effects on small airway dysfunction. All nicotine containing products are associated with an increased cardiovascular risk compared with no product use.

Wide antral circumferential vs. ostial pulmonary vein isolation using pulsed field ablation-the butterfly effect.

Background: Wide antral circumferential ablation (WACA) in comparison to ostial pulmonary vein (PV) isolation (PVI) has been attributed with improved rhythm outcome. We investigated the feasibility, lesion formation, and rhythm outcome of WACA-PVI in comparison to ostial-PVI using pulsed field ablation (PFA). Methods: Symptomatic atrial fibrillation (AF) patients (69 years, 67% male; 67% paroxysmal AF) were prospectively enrolled into our single-center registry and underwent first-time ostial-PFA or WACA-PFA, N = 15 each. In all patients, eight pulse trains (2 kV/2.5 s, bipolar, biphasic, 4× basket/flower configuration each) were delivered to each PV. In WACA-PFA, two extra pulse trains in a flower configuration were added to the anterior and posterior antrum of the PVs. For comparison of PFA lesion size, pre- and post-ablation left atrial (LA) voltage maps were acquired using a multipolar spiral catheter together with a three-dimensional electroanatomic mapping system. Results: WACA-PFA resulted in a significant larger lesion formation than ostial-PFA (45.5 vs. 35.1 cm2, p = 0.001) with bilateral overlapping butterfly shape-like lesions and concomitant posterior LA wall isolation in 73% of patients. This was not associated with increased procedure time, sedation dosage, or exposure to radiation. One-year freedom from AF recurrence was numerically higher after WACA-PFA than ostial-PFA (94% vs. 87%) but not statistically significant (p = 0.68). No organized atrial tachycardias (ATs) were observed. Ostial-PFA patients more often underwent re-ablation due to recurrent AF episodes. Conclusion: WACA-PFA is feasible and resulted in significantly wider lesion sets than ostial-PFA. Concomitant posterior LA wall isolation occurred as an epiphenomenon in the majority of patients. The WACA approach was associated with neither increased procedure and fluoroscopy times nor statistically significant differences in 1-year rhythm outcome. ATs were absent.

Severe aortic stenosis management in heart valve centres compared with primary/secondary care centres.

OBJECTIVE: Current guidelines recommend use of heart valve centres (HVCs) to deliver optimal quality of care for patients with valve disease but there is no evidence to support this. The hypothesis of this study is that patient care with severe aortic stenosis (AS) will differ in HVCs compared with satellite centres. We aimed to compare the treatment of patients with AS at HVCs (tertiary care hospitals with full access to AS interventions) to satellites (hospitals without such access). METHODS: IMPULSE enhanced is a European, observational, prospective registry enrolling consecutive patients with newly diagnosed severe AS at four HVCs and 10 satellites. Clinical characteristics, interventions performed and outcomes up to 1 year by site-type were examined. RESULTS: Among 790 patients, 594 were recruited in HVCs and 196 in satellites. At baseline, patients in HVCs had more severe valve disease (higher peak aortic velocity (4.3 vs 4.1 m/s; p=0.008)) and greater comorbidity (coronary artery disease (CAD) (44% vs 27%; p<0.001) prior myocardial infarction (MI) (11% vs 5.1%; p=0.011) and chronic pulmonary disease (17% vs 8.9%; p=0.007)) than those presenting in satellites. An aortic valve replacement was performed more often by month 3 in HVCs than satellites in the overall population (52.6% of vs 31.3%; p<0.001) and in symptomatic patients (66.7% vs 43.2%, p<0.001). One-year survival rate was higher for patients in HVCs than satellites (HR2.19; 95% CI 1.28 to 3.73 total population and 2.89 (95%CI 1.64 to 5.11) for symptomatic patients. CONCLUSIONS: Our data support the implementation of referral pathways that direct patients to HVCs performing both surgery and transcatheter interventions. TRIAL REGISTRATION NUMBER: NCT03112629.

Should all dysfunctional high-voltage leads be extracted? Results of a single-centre long-term registry.

AIMS: A considerable number of lead defects occurs during long-term cardioverter defibrillator therapy. Evidence-based strategies for the handling of chronically implanted, non-functional high-voltage (HV) leads are mandatory. METHODS AND RESULTS: Patient outcome after abandonment of HV leads was retrospectively compared with patient outcome following other lead revision strategies and following primary implantation. A total of 903 consecutive patients undergoing 997 implantable cardioverter defibrillator (ICD) implantations or lead revisions were followed for a mean period of 48.8 ± 37.8 months. One or more additional HV leads were placed in 60 patients. An additional pace/sense lead was implanted in 13 patients. Extraction and replacement of a dysfunctional HV lead was performed in 21 patients. The overall rate of complications including artefact sensing, ineffective defibrillation, symptomatic subclavian vein thrombosis, and other lead defects did not differ between patients with and without an additional HV lead (10.0 vs. 8.9%, P = 0.32). Survival without lead associated complications did not differ between groups. Results remained unchanged after correction for covariates. CONCLUSIONS: Abandoned HV leads did not increase the risk of ICD system-related complications in the majority of patients. Thus, a general lead extraction policy of dysfunctional HV leads cannot be advised in an average ICD population. Recommendations may not apply for young and physically active patients, in whom HV lead extraction must be considered.

A standardized education protocol significantly reduces traumatic injuries and syncope recurrence: an observational study in 316 patients with vasovagal syncope.

AIMS: The aim of this study was to assess the role of a non-pharmacological approach on the frequency of traumatic injuries and syncope recurrence in patients with vasovagal syncope and normal hearts. We report the experience in our syncope centre with a standardized education and teaching protocol for patients with vasovagal syncope. The treatment of vasovagal syncope is often complex and discouraging. Besides medical options, behaviour modification is a main component of therapy but has no statistical evidence to support its use. METHODS AND RESULTS: Between January 1999 and September 2006, we prospectively enrolled all patients with vasovagal syncope. The patients were counselled about the benign nature of their disease. Specific recommendations were made according to a standardized education protocol established at our syncope centre. A pre-/post-study was conducted to investigate the effectiveness of our approach on syncope recurrence and frequency of injury as the study endpoints. Complete follow-up data were available from 85% of the study population (316 of 371) after a mean time of 710 ± 286 days (mean age 50 years; standard deviation ± 18 years, 160 female). Eighty-seven patients (27.5%) had a syncope recurrence with 22 suffering an injury during syncope. During the follow-up period, the syncope burden per month was significantly reduced from 0.35 ± 0.03 at initial presentation to 0.08 ± 0.02 (P< 0.001). The frequency of traumatic syncope was significantly lower at the time of recurrence compared with the initial presentation (25 vs. 42%; McNemar's test P= 0.02). CONCLUSION: A standardized education protocol significantly reduces traumatic injuries and syncope recurrence in patients with vasovagal syncope.

A strategy to achieve CRT response in permanent atrial fibrillation without obligatory atrioventricular node ablation.

BACKGROUND: Cardiac resynchronization therapy (CRT) is an established method in patients with severe heart failure and wide QRS configuration, particularly during sinus rhythm (SR). In CRT patients with permanent atrial fibrillation (AF), there is no general consensus regarding the need for atrioventricular node (AVN) ablation. The aim of this study was to evaluate the benefit of CRT in permanent AF with and without AVN ablation. METHODS: New York Heart Association classification, QRS duration, and echocardiographic parameters were assessed before and after CRT with a follow-up of 12 ± 3 months. Two hundred thirty patients in SR and 46 patients with permanent AF of 2.1 ± 0.5 years duration were studied. AVN ablation was performed only in AF patients with insufficient pharmacological rate control evidenced by ≤80 % ventricular stimulation. RESULTS: Fifteen AF patients underwent AVN ablation. Biventricular pacing comparably improved functional status, left ventricular ejection fraction, and left ventricular end-diastolic dimensions in all treated groups. Biventricular stimulation percentage was 10% lower in pharmacologically treated AF patients over 1 year as compared to patients in SR and to AF patients undergoing AVN ablation, which did not affect outcome in this patient population. CONCLUSION: In patients with permanent AF and CRT, an AVN ablation strategy might not be strictly required in all patients.

Cardiovascular functions and arterial stiffness after JUUL use.

INTRODUCTION: The rapid growth in the e-cigarette market after the launch of JUUL e-cigarettes led to much discussion on the potential benefits and risks of pods, JUUL devices, and conventional e-cigarettes compared with combustible cigarettes. Independent data are required to assess the effects of these products on cardiovascular surrogate parameters and cardiovascular risk. METHODS: We conducted a single-center three-arm study comparing combustible cigarettes with JUUL e-cigarettes with the old and new technology. We recruited 32 participants who were active smokers (n=15) or vapers (n=17) and performed a total of 39 measurements before and 5, 15, and 30 minutes, after participants smoked a combustible cigarette or vaped a JUUL e-cigarette with the new or old technology. Measurements included peripheral and central blood pressures and parameters of arterial stiffness, including pulse wave velocity and augmentation index. RESULTS: Peripheral systolic blood pressure, central blood pressure, and peripheral pulse rate increased significantly in all three groups (each p<0.05). Heart rate (HR) changes lasted significantly longer than blood pressure changes. The augmentation index and pulse wave velocity increased in all three groups, and a multivariate analysis of variance showed that the increases were independent of systolic blood pressure, sex, age, device, and HR. CONCLUSIONS: Changes in blood pressure and arterial stiffness are similar after cigarette smoking and JUUL use. These changes may be associated with an increased cardiovascular risk compared with no product use. However, a long-term follow-up evaluation of JUUL use and a head-to-head comparison with conventional e-cigarettes are still needed.

Negative Impact of the UEFA European Soccer Championship on Central Hemodynamics and Arterial Stiffness: A Multicenter Study.

(1) Background: watching sporting events may trigger cardiovascular events by elevating emotional stress levels. The underlying reasons and specific populations at risk are not well defined. (2) Methods: we conducted a multicenter prospective trial at three German sites during the UEFA Soccer EC 2012 and 2021 comprising 52 healthy participants (noCVD) and 18 patients hospitalized with cardiovascular disease (CVD). Subjects were studied during matches of the German national team (GP) as well as corresponding matches without German participation (noGP). Peripheral and central blood pressure (BP) and parameters of arterial stiffness were measured (Mobil-O-Graph™, I.E.M., Stolberg, Germany) before, during, and after the matches. (3) Results: in terms of CVD, peripheral as well as central BP and heart rate increased significantly during GP as well as noGP matches and remained elevated beyond the end of the matches. Likewise, arterial stiffness parameters and vascular resistance were higher during the matches and remained elevated after the matches. No consistent significant differences were found between GP and noGP matches. (4) Conclusions: this is the first study on real-life changes in hemodynamics during sport-associated emotional stress, with comparison between noCVD and CVD. We found that alterations were profound in CVD and remained elevated even after the matches.

Predicting recurrence of vasovagal syncope: a simple risk score for the clinical routine.

BACKGROUND: Predictors for recurrence of syncope are lacking in patients with vasovagal syncope. The aim of this study was to identify risk factors for recurrence of syncope and develop a simple prognostic risk score of clinical value. METHODS: Two hundred seventy-six patients with a history of vasovagal syncope were prospectively followed for 2 years. Diagnosis of vasovagal syncope was based on clinical history and negative standard work-up. Inclusion in the study was independent from the result of the head-up tilt test, which was performed in all cases. Risk factors for syncope recurrence were evaluated by the Cox proportional hazards regression model and implemented in a risk score, which was validated with the log-rank test and an internal cross-validation. RESULTS: The Cox-regression analysis identified the number of previous syncopal events, history of bronchial asthma, and female gender as predictors for syncope recurrence (all P < 0.05). In contrast, head-up tilt test response had no predictive value (P = 0.881). Developing a risk score, study patients were identified as having high (recurrence rate during 2 years of follow-up: 37.2%), intermediate (24.8%), and low (6.5%) risk for syncope recurrence (receiver operating characteristic [ROC] of score 0.83, P < 0.01; Log-rank test for event-free survival, P < 0.005). CONCLUSIONS: In patients with vasovagal syncope, risk of recurrence can be stratified and is predictable based on a simple risk score.

Caseload management and outcome of patients with aortic stenosis in primary/secondary versus tertiary care settings-design of the IMPULSE enhanced registry.

Background: Severe aortic stenosis (AS) is one of the most common and most serious valve diseases. Without timely intervention with surgical aortic valve replacement or transcatheter aortic valve replacement, patients have an estimated survival of 2-3 years. Guidelines for the treatment of AS have been developed, but studies suggest that as many as 42% of patients with AS are not treated according to these recommendations.The aims of this registry are to delineate the caseload of patients with AS, outline the management of these patients and determine appropriateness of treatments in participating centres with and without onsite access to surgery and percutaneous treatments. Methods/design: The IMPULSE enhanced registry is an international, multicentre, prospective, observational cohort registry conducted at four central full access centres (tertiary care hospitals) and at least two satellite centres per hub (primary/secondary care hospitals). An estimated 800 patients will be enrolled in the registry and patient follow-up will last for 12 months. Discussion: In addition to the primary aims determining the caseload management and outcome of patients with AS in primary, secondary and tertiary care settings, the registry will also determine a time course for the transition from asymptomatic to symptomatic status and the diagnostic steps, treatment decisions and the identification of decision-makers in tertiary versus primary/secondary care hospitals. The last patient will be enrolled in the registry in 2018 and results of the registry are anticipated in 2019. Registration number: NCT03112629.

Biphasic versus monophasic shock for external cardioversion of atrial flutter: a prospective, randomized trial.

BACKGROUND: External cardioversion is effective to terminate persistent atrial flutter. Biphasic shocks have been shown to be superior to monophasic shocks for ventricular defibrillation and atrial fibrillation cardioversion. The purpose of this trial was to compare the efficacy of rectilinear biphasic versus standard damped sine wave monophasic shocks in symptomatic patients with typical atrial flutter. METHODS: 135 consecutive patients were screened, 95 (70 males, mean age 62 +/- 13 years) were included. Patients were randomly assigned to a monophasic or biphasic cardioversion protocol. Forty-seven patients randomized to the monophasic protocol received sequential shocks of 100, 150, 200, 300 and 360 J. Forty-eight patients with the biphasic protocol received 50, 75, 100, 150 or 200 J. RESULTS: First-shock efficacy with 50-Joule, biphasic shocks (23/48 patients, 48%) was significantly greater than with the 100-Joule, monophasic waveform (13/47 patients, 28%, p = 0.04). The cumulative second-shock efficacy with the 50- and 75-Joule, biphasic waveform (39/48 patients, 81%) was significantly greater than with the 100- and 150-Joule, monophasic waveform (25/47 patients, 53%, p < 0.05). The cumulative efficacy for the higher energy levels showed naturally no significant difference between the two groups. The amount of the mean delivered energy was significantly lower in the biphasic group (76 +/- 39 J) compared to the monophasic one (177 +/- 78 J, p < 0.05). CONCLUSIONS: For transthoracic cardioversion of typical atrial flutter, biphasic shocks have greater efficacy and the mean delivered current is lower than for monophasic shocks. Therefore, biphasic cardioversion with lower starting energies should be recommended.

Effects of continuous and triggered atrial overdrive pacing on paroxysmal atrial fibrillation in pacemaker patients.

BACKGROUND: The aim of the study was to compare the effects of different pacing strategies to prevent paroxysmal atrial fibrillation (AF): triggered atrial overdrive pacing versus the combination of triggered and continuous overdrive pacing. METHODS: Patients with an indication for dual-chamber pacing (Selection 9000, Prevent AF; Vitatron B.V., Arnhem, the Netherlands) and a history of paroxysmal AF were randomized to triggered atrial pacing (three pacing functions, "triggered group": PAC Suppression, Post-PAC Response, and Post-Exercise Response) or to the combination of continuous (Pace Conditioning) and triggered atrial pacing (four pacing functions, "combined group"). After 3 months, there was a crossover to the other pacemaker setting. RESULTS: In 171 enrolled patients, the median AF burden of the combined group was with 2.1% versus 0.1% in the triggered group (P = 0.014). Fewer AF episodes were observed in the triggered (median: 7) than in the combined group (median: 116; P = 0.016). The combined group had more frequent atrial pacing (median 97%) than the triggered group with 85% (P < 0.001), but ventricular pacing was not significantly different with 95% and 96% in the combined and triggered group, respectively. After the crossover, the AF burden increased in the triggered group to 0.3% and decreased in the combined group to 0.4%. CONCLUSIONS: Triggered atrial pacing functions alone resulted in a low AF burden. The additional activation of continuous atrial overdrive pacing increased the percentage of atrial pacing, but had no beneficial effects on the prevention of paroxysmal AF.