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Background: Ablation of the aortic sinus of Valsalva in adults for ectopic atrial tachycardia (EAT) and ventricular tachycardia (VT)/premature ventricular complexes (PVCs) has been reported in only a very few patients. Limited data exist concerning the safety of aortic ablation. Objective: The purpose of this study was to confirm aortic wall and aortic valve integrity after ablation and to evaluate for potential cerebral embolism due to thrombus formation at aortic wall lesions. Methods: From January 2006 to August 2007, 21 patients with EAT (n = 6) or VT/PVCs (n = 15) originating from the sinus of Valsalva underwent successful ablation. The aortic wall structure was evaluated using transesophageal echocardiography (TEE) and magnetic resonance imaging (MRI) the day after ablation and at 6-month follow-up for all patients. To rule out cerebral embolism due to postablation thromboembolic events, a cerebral MRI was performed immediately after ablation in six patients and at 6-month follow-up in all patients. Ablation success was defined by 24-hour Holter monitoring before hospital discharge and after 6 months. Results: Aortic wall integrity was confirmed in all patients by TEE and MRI. Cerebral MRI showed evidence of silent cerebral ischemia in one patient. Aortic valve thickening was detected in one patient by TEE. Conclusion: Ablation in the aortic sinus of Valsalva is a safe and effective approach for atrial tachycardia or VT/PVCs. The incidence of silent ischemia needs further evaluation. [ABSTRACT FROM AUTHOR]

Introduction: Pulmonary vein isolation (PVI) is widely practiced for treating atrial fibrillation. Transseptal access is necessary with one or even more transseptal sheaths to perform PVI.Methods: In this prospective study, 31 patients were examined with transesophageal echocardiography before, immediately after and in a 3-, 6- and 12-month follow-up period for evaluation of iatrogenic atrial septal defect (iASD). All patients underwent PVI with double transseptal puncture.Results: An iASD was detected in 27/31 patients (87%) with a maximum diameter of 1.0 mm. After 3 months, the iASDs were completely closed in 26/27 (96.3%) patients. In 1/27 (3.7%) patients, there was an iASD detectable even after 12 months. Clinically no patient suffered from cerebral or cardiac embolism in the follow-up period.Conclusions: We were only able to find small iASDs with left to right shunting after PVI but none with right to left shunting. iASDs following PVI show a high spontaneous closure rate already at 3 months of follow-up and are not associated with an increased rate of paradoxical embolism. [ABSTRACT FROM AUTHOR]

Background: Pulmonary vein isolation (PVI) has become the cornerstone procedure for the treatment of symptomatic drug-resistant atrial fibrillation (AF). At the present time, circumferential PVI (CPVI) using irrigated radiofrequency (RF) is the mostly used ablation technique. However, for CPVI, precise catheter navigation and excellent catheter stability is crucial thereby requiring experienced operators. Robotic navigation systems have been introduced to facilitate catheter navigation and to improve catheter stability, therefore potentially increasing procedural success and making CPVI accessible to less experienced operators. To date, no prospective randomized trial has evaluated the efficacy and safety of CPVI using RNS compared to manually performed ablation., Methods: In this prospective international multicenter noninferiority trial, 258 patients with either paroxysmal or short-standing persistent AF will be randomized for comparison of PVI using either manual or robotic ablation. In all patients, CPVI will be performed using irrigated RF ablation in combination with a 3D mapping system. The primary endpoint of the trial is the absence of AF or atrial tachycardia without antiarrhythmic drug therapy during 12-month follow-up. Secondary endpoints will be evaluation of periprocedural complications and procedural data such as procedure time, fluoroscopy time, as well as the incidence of esophageal injury assessed by endoscopy within 48 hours after the procedure., Conclusion: The "Man and Machine Trial" is the first prospective international randomized controlled multicenter noninferiority trial to compare manually performed CPVI with robotically navigated CPVI, evaluating both the safety and efficacy of the 2 techniques during a 12-month follow-up period., (© 2012 Wiley Periodicals, Inc.)

Introduction: The Hansen Robotic system has been utilized in ablation procedures for atrial fibrillation (AF). However, because of the lack of tactile feedback and the rigidity of the robotic sheath, this approach could result in higher risk of complications. This worldwide survey reports a multicenter experience on the methodology, efficacy, and safety of the Hansen system in AF ablations., Methods and Results: A questionnaire addressing questions on patient's demographics, procedural parameters, ablation success rate and safety information was sent to all centers where more than 50 robotic AF ablation cases have been performed. From June 2007 to December 2009, 1,728 procedures were performed at 12 centers utilizing the Hansen robotic navigation technology. The overall complication rate was 4.7% and the success rate was 67.1% after 18 ± 4 months of follow-up. In 5 low volume centers there appeared to be a learning curve of about 50 cases (complication rate 11.2% for the first 50 cases vs 3.7% for the 51-100 cases; P = 0.044) and a trend showing a decrease of complication rate with increasing case volume. However, in the remaining 7 centers no learning curve was present and the complication rate was stable over time (3.7% for the first 50 cases vs 3.6% for the 51st case thereafter; P = 0.942)., Conclusion: The Hansen robotic system can be used for AF ablation safely. In low volume centers, there appeared to be a learning curve of the first 50 cases after which the complication rate decreased. With a higher case volume, the success rate increased., (© 2012 Wiley Periodicals, Inc.)

The aim of this study was to evaluate the outcome and treatment quality of transfer percutaneous coronary intervention (PCI) in older patients with acute STEMI. In this prospective study all patients with diagnosed acute (pain-to-balloon≤12 h) STEMI transferred to our institution for primary PCI (n=400) between January 2005 and October 2007 were under investigation. Overall 125 older patients with age ≥70 years were included (mean age 77.5±4.9 years; 77 males). Pre-hospital delays were more common in older patients with longer pain-to-balloon: median (range)=85 (5-629) vs. 66 (1-688) p=0.031, and pain-to-first medical-contact-times: median: 206 (84-711) vs. 172 (45-720); p=0.001. A trend towards a higher (non-significant) rate of major 5/125 (5%) vs. 5/275 (1.8%), p=0.195 and minor 10/125 (8%) vs. 14/275 (5.1%). p=0.256 bleeding complications in older patients was evident. In-hospital mortality was significantly higher in older patients compared to the younger patients group: 13/125, 10.4% vs. 8/275, 2.9%, p=0.002). Overall mortality at 30-day follow-up was 11.2% in older and 3.3% in younger patients: 14/125 vs. 9/275, p=0.002. Transfer PCI is an effective treatment strategy for older patients with acute ST-elevation myocardial infarction. Overall-30-day mortality in older STEMI-patients transferred for primary PCI is comparably low., (Copyright © 2010. Published by Elsevier Ireland Ltd.)

Aims: To define frequency and predictors of aborted myocardial infarctions (MI) after primary angioplasty., Methods and Results: We analysed 196 consecutive patients with the clinical diagnosis of ST-elevation acute coronary syndrome (ST-ACS) admitted for primary angioplasty to one interventional facility between October 2005 and September 2006. Aborted MI was defined as a creatine increase of less than two times the upper limit of normal, combined with typical evolutionary electrocardiographic changes. Masquerading MI was diagnosed if evolutionary changes were missing or could be attributed to other causes. Thirty-four patients (17,3%) had an aborted and nine (4,6%) a masquerading MI. The main predictor of abortion was Thrombolysis In Myocardial Infarction (TIMI) flow 2 or 3 prior to procedure. The in-hospital mortality of aborted MI was 0%, the one year mortality 2.9%. Sixteen patients without prior or inter-current myocardial infarction had a preserved ejection fraction on cardiac MR at 12 months; in six patients even without any detection of late enhancement., Conclusions: There is a substantial proportion of aborted myocardial infarction after primary angioplasty, corresponding to a small or even non detectable scar formation in terms of late enhancement on cardiac MR. Preprocedural TIMI flow 2 or 3 is the main predictor of aborted MI.

Aims: The aim of this study was to assess the guideline-adherent feasibility of area-wide primary angioplasty in rural German surroundings and its impact on reperfusion and outcome in patients with acute ST-elevation myocardial infarction (STEMI)., Methods and Results: All consecutive patients with acute STEMI (n = 347) admitted to any of the hospitals (5 non invasive and 1 invasive with established 24 h/7 days primary angioplasty service) in a 350.000 inhabitant rural area during the year 2002 (n = 184) and 2005 (n = 163) were included in this registry. In 2002, emergency medical services transferred acute STEMI patients to the nearest emergency room, where reperfusion therapy (fibrinolysis or primary angioplasty) was organised. In 2005, all patients were transferred directly to the cathlab bypassing any emergency room when possible. Primary angioplasty increased from 53 to 89% (p < 0.01), fibrinolysis decreased from 27 to 2% (p < 0.01) and the no revascularisation rate from 21 to 9% (p < 0.01). Onset of pain to balloon time in primary angioplasty was reduced from median 339 to 191 min (p < 0.01), median first medical contact to balloon time in 2005 was 101 min. Overall, 6-month mortality decreased from 19 to 10% (p = 0.03)., Conclusions: After transition to a uniform primary angioplasty concept, an increase in overall reperfusion rates and a decrease in time delays could be observed in a rural German infarction network.

Introduction: Recently, results describing pulmonary vein isolation (PVI) on patients using a robotic navigation system (RNS) in a high-volume center specialized in pulmonary vein isolation were published. The main purpose of this prospective study was to evaluate the learning curve of new users of RNS in a community hospital and to address the effectivity of RNS in electrophysiological settings with fewer patients. Radiation times, procedural times, feasibility, and safety with the RNS were assessed., Methods: PVI using the RNS was performed on 100 consecutive patients with symptomatic paroxysmal (n = 56, 56%) or persistent atrial fibrillation (AF). To assess the learning curve of practitioners with first-time use of RNS, patients were divided into four groups of 25 patients each (Q1-Q4). Procedural times as well as radiation times, complications, and outcome after a 6-month follow-up period were assessed for each quartile. All patients were ablated by the same physician., Results: Comparing the four patient groups, a continuous and significant reduction of procedural and radiation times was seen in the first 75 patients (Q1-Q3), whereas no further improvement was seen in the consecutive patients (Q3-Q4). One pericardial tamponade occurred in the course of 100 patients (1%). Overall success rate after a 6-month follow-up period was 74% in patients with paroxysmal and persistent AF. Comparing the four quartiles there was a higher but non-significant number of patients with freedom of atrial fibrillation after a 6-month follow-up in the subsequent groups (Q2-Q4) when compared to group 1., Conclusions: This data suggest that RNS is feasible and safe when performed in a community hospital with a significant reduction of radiation times and procedure times within the first 75 patients and with similar success and complication rates as compared to high-volume centers.

Unlike the standard quarterly or semi-annual direct ambulatory device interrogations procedures, state-of-the-art implantable electronic cardiovascular devices (IECD) enable their wireless remote interrogation and monitoring, and automatically send reports and special alerts on a daily basis. This allows physicians to respond more proactively to changes in patient or device status, more appropriately triage patient care, and more efficiently perform the post-implant ambulatory follow-ups. This review presents the-state-of the-art technology of remote IECD monitoring and summarizes the main clinical observations published through June 2008. Cardiovascular remote monitoring systems made by several manufacturers are currently in various phases of development, clinical investigation, and medical applications. Data collected in several completed and ongoing studies strongly suggest that this new technology will make important contributions, particularly with respect to the facilitation of IECD follow-ups, enhancement of patient safety and quality of life, and lowering of medical costs. Further technological advances and a more clear understanding and appreciation of the clinical and economic benefits of telecardiology, will likely increase sharply the use of remote IECD monitoring in upcoming years.

New methods for the analysis of arrhythmias and their hemodynamic consequences have been applied in risk stratification, in particular to patients after myocardial infarction. This study investigates the suitability of short-term heart rate turbulence (HRT) analysis in comparison to heart rate and blood pressure variability as well as baroreceptor sensitivity analyses to characterise the regulatory differences between patients with dilated cardiomyopathy (DCM) and healthy controls. In this study, 30 minutes data of non-invasive continuous blood pressure and ECGs of 37 DCM patients and 167 controls measured under standard resting conditions were analysed. The results show highly significant differences between DCM patients and controls in heart rate and blood pressure variability as well as in baroreceptor sensitivity parameters. Applying a combined heart rate-blood pressure trigger, ventricular premature beats were detected in 24.3% (9) of the DCM patients and 11.3% (19) of the controls. This fact demonstrates the limited applicability of short-term HRT analyses. However, the HRT parameters showed significant differences in this subgroup with ventricular premature beats (turbulence onset: DCM: 1.80+/-2.72, controls: - 4.34+/-3.10, p<0.001; turbulence slope: DCM: 6.75+/-5.50, controls: 21.30+/-17.72, p=0.021). Considering all (including HRT) parameters in the subgroup with ventricular beats, a discrimination rate between DCM patients and controls of 88.0% was obtained (max. 6 parameters). The corresponding value obtained for the total group was 86.3% (without HRT parameters). Comparable classification rates and high correlations between heart rate turbulence and variability and baroreflex parameters point to a more universal applicability of the latter methods.

Introduction: A novel mapping/ablation catheter using a coaxially ablation electrode (E) that is moveable between distal and proximal ring electrodes along its shaft was used to create a linear lesion over the cavotricuspid isthmus (CTI) and bidirectional block in 32 patients (21 men; age 38-79 years) undergoing ablation for counterclockwise atrial flutter., Methods and Results: Two bipolar electrograms (E1 and E2) were recorded: between E and the distal ring electrode and between E and the proximal ring electrode. Interpole distance varied for both as the E traversed the slide shaft. Given the catheter's concept, these bipoles are orientated exactly along the line of lesion creation. Prior to ablation, unitary bipolar electrograms were recorded along the catheter slide shaft position. As the CTI lesion was created (E moved along the catheter slide shaft in 2-mm steps with radiofrequency energy delivered to achieve 65 degrees C for 60 sec at each), double potentials (DP) were observed. Interpotential distance became maximal with completion of the linear lesion and bidirectional block. DPs were noted in all these procedures. With pacing from the low septal right atrium at bidirectional block creation, interpotential timing was 140.9 +/- 15 msec and from the low right atrial free wall was 145.13 +/- 18 msec. In sinus rhythm, DP interpotential timing was less (35.13 +/- 9 msec) as activation fronts arrived from both septal and anterior atrial aspects., Conclusion: Bipolar recordings from the coaxially moveable electrode catheter provide unique electrogram data. DPs recorded during and after linear lesion creation can define conduction block across that lesion without the need for additional mapping catheters or complex mapping technology.

Background: We tested whether or not heart rate variability (HRV) changes can serve as early signs of ventricular tachycardia (VT) and predict slow and fast VT in patients with an implantable cardioverter defibrillator (ICD)., Methods and Results: We studied the ICD stored 1000 beat-to-beat intervals before the onset of VT (131 episodes) and during a control time without VT (74 series) in 63 chronic heart failure ICD patients. Standard HRV parameters as well as two nonlinear parameters, namely 'Polvar10' from symbolic dynamics and the finite time growth rates 'Fitgra9' were calculated. Comparing the control and the VT series, no linear HRV parameter showed a significant difference. The nonlinear parameters detected a significant increase in short phases with low variability before the onset of VT (for time series with less than 10% ectopy, P<0.05). Subdividing VT into fast (cycle length 270 ms) events, we found that the onset of slow VT was characterized by a significant increase in heart rate, whereas fast VT was triggered during decreased heart rates, compared to the control series., Conclusions: Our data may permit the development of automatic ICD algorithms based on nonlinear dynamic HRV parameters to predict VT before it starts. Furthermore, they may facilitate improved prevention strategies.

The main intention of this contribution is to measure the coupling between bivariate time series using the dual sequence method to estimate the baroreflex as well as a nonlinear regression approach, namely the maximal correlation method, to get a better understanding of the underlying processes. The data we analyse are heart rate and blood pressure variability time series from 27 patients with dilated cardiomyopathy as well as from a control group of 27 age- and sex-matched healthy subjects. The results strongly indicate and confirm the mechanisms of respiratory sinus arrhythmia in heart rate. Revealing the coupling direction and the strength of coupling between heart rate and blood pressure via optimal transformations in addition to the baroreflex estimation seems to be a very promising approach.

Ventricular tachycardia or fibrillation (VT-VF) as fatal cardiac arrhythmias are the main factors triggering sudden cardiac death. The objective of this study is to find early signs of sustained VT-VF in patients with an implanted cardioverter-defibrillator (ICD). These devices are able to safeguard patients by returning their hearts to a normal rhythm via strong defibrillatory shocks; additionally, they store the 1000 beat-to-beat intervals immediately before the onset of a life-threatening arrhythmia. We study these 1000 beat-to-beat intervals of 17 chronic heart failure ICD patients before the onset of a life-threatening arrhythmia and at a control time, i.e., without a VT-VF event. To characterize these rather short data sets, we calculate heart rate variability parameters from the time and frequency domain, from symbolic dynamics as well as the finite-time growth rates. We find that neither the time nor the frequency domain parameters show significant differences between the VT-VF and the control time series. However, two parameters from symbolic dynamics as well as the finite-time growth rates discriminate significantly both groups. These findings could be of importance in algorithms for next generation ICD's to improve the diagnostics and therapy of VT-VF.