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Aims: Pulmonary vein isolation (PVI) aims at eliminating symptomatic atrial fibrillation. In this regard, the most relevant indication for this procedure is the reduction of symptoms and improvement of quality of life (QoL) in patients who remain symptomatic despite antiarrhythmic drug treatment. We investigated the relation between documented atrial fibrillation recurrences and QoL in patients after PVI., Methods: One hundred and six PVIs were performed in 99 patients. Follow-up was mainly performed at referring hospitals. Short Form 36 (SF-36) QoL questionnaires were completed before and 1 year after PVI. Electrocardiographic recordings from the first postprocedural year were retrospectively collected, 3 months blanking excluded. Atrial fibrillation recurrence was defined as any recurrence of atrial arrhythmia documented on ECG or 24-h-Holter., Results: Before PVI, patients had lower QoL than the general Dutch population in 7/8 SF-36 questionnaire subscales (sumQoL 419.4 ± 161 vs. 617.9, P < 0.001). Atrial fibrillation recurred in 52 (49%) patients. In these patients, four subscales increased following PVI (physical functioning P < 0.001, role physical P = 0.006, bodily pain P = 0.011 and social functioning P = 0.047). SumQoL remained lower than the general Dutch population (546.7 ± 157, P = 0.003). In patients without documented recurrences, QoL improved to a level similar to that of the general Dutch population (602.9 ± 148; P = 0.46). The number of electrocardiographic recordings was lower in the group without documented recurrences (2.5 ± 1.8 vs. 3.8 ± 1.7, P = 0.002)., Conclusion: In patients without documentation of atrial fibrillation, QoL increased up to the level of the general population after PVI, but it remained lower in patients with recurrences. In the latter group more ECGs were done, suggesting that QoL relates particularly to symptomatic episodes. Improvement of QoL is therefore an important attribute of PVI.

Myocardial conduction velocity is important for the genesis of arrhythmias. In the normal heart, conduction is primarily dependent on fiber direction (anisotropy) and may be discontinuous at sites with tissue heterogeneities (trabeculated or fibrotic tissue). We present a semi-automated method for the accurate measurement of conduction velocity based on high-resolution activation mapping following central stimulation. The method was applied to activation maps created from myocardium from man, sheep and mouse with anisotropic and discontinuous conduction. Advantages of the presented method over existing methods are discussed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Atrial fibrosis is an important component of the arrhythmogenic substrate in patients with atrial fibrillation (AF). We studied the effect of interstitial fibrosis on conduction velocity (CV) in the left atrial appendage of patients with AF., Methods and Results: Thirty-five left atrial appendages were obtained during AF surgery. Preparations were superfused and stimulated at 100 beats per minute. Activation was recorded with optical mapping. Longitudinal CV (CVL), transverse CV (CVT), and activation times (> 2 mm distance) were measured. Interstitial collagen was quantified and graded qualitatively. The presence of fibroblasts and myofibroblasts was assessed immunohistochemically. Mean CVL was 0.55 ± 0.22 m/s, mean CVT was 0.25 ± 0.15 m/s, and the mean activation time was 9.31 ± 5.45 ms. The amount of fibrosis was unrelated to CV or patient characteristics. CVL was higher in left atrial appendages with thick compared with thin interstitial collagen strands (0.77 ± 0.22 versus 0.48 ± 0.19 m/s; P = 0.012), which were more frequently present in persistent patients with AF. CVT was not significantly different (P = 0.47), but activation time was 14.93 ± 4.12 versus 7.95 ± 4.12 ms in patients with thick versus thin interstitial collagen strands, respectively (P = 0.004). Fibroblasts were abundantly present and were associated with the presence of thick interstitial collagen strands (P = 0.008). Myofibroblasts were not detected in the left atrial appendage., Conclusions: In patients with AF, thick interstitial collagen strands are associated with higher CVL and increased activation time. Our observations demonstrate that the severity and structure of local interstitial fibrosis is associated with atrial conduction abnormalities, presenting an arrhythmogenic substrate for atrial re-entry., (© 2015 American Heart Association, Inc.)

Background: In patients with atrial fibrillation (AF), the autonomic nervous system is supposed to play an role in triggering AF; however, little is known of the effect on atrial conduction characteristics., Objective: The purpose of this study was to study the effect of ganglionic plexus (GP) stimulation during sinus rhythm on atrial and pulmonary vein conduction in patients during thoracoscopic surgery for AF METHODS: In 25 patients, the anterior right ganglionic plexus (ARGP) was stimulated (16 Hz, at 1, 2, and 5 mA). Epicardial electrograms were recorded using a 48-electrode map from the right pulmonary vein (RPV) or right atrial (RA). Intra-atrial activation time (IAT), local activation time (LAT), and inhomogeneity of conduction (IIC) were determined. ECG parameters (P-P, P-R interval) were measured., Results: P-P interval was 956 ± 157 ms (range 768-1368 ms), and P-R interval was 203 ± 37 ms (range 136-280 ms). After ARGP stimulation, a short-lasting increase of P-P interval was observed, more prominent at higher output (1 mA = 82 ms, 2 mA = 180 ms, 5 mA = 268 ms, all P <.01 vs baseline). P-R interval remained unchanged. IAT was 34.4 ms (range 5.6-50.3 ms) at the RA and 105.8 ms (range 79.7-163.3 ms) at the RPV. After 1-mA stimulation IAT increased, in patients taking beta-blockers (P = .001), or it decreased, and this change persisted after subsequent stimulation at higher current (1 mA, P = .001; 2 mA, P = .401; 5 mA, P = .593). Similar changes were observed for LAT and IIC., Conclusion: ARGP stimulation results in a short-lasting, output-dependent decrease in sinus node frequency due to a parasympathetic response. Stimulation of the ARGP induced a prolonged increase or decrease in conduction characteristics in patients with AF, consistent with a persistent differential parasympathetic and/or sympathetic response., (Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Introduction: Patients with atrial fibrillation (AF) with enlarged atria or previous pulmonary vein isolation (PVI) are challenging patients for catheter ablation. Thoracoscopic surgery is an effective treatment for these patients but comes at the cost of an increase in adverse events. Recently, electrophysiological (EP) guided approaches to thoracoscopic surgery have been described which consist of EP guidance by measurement of conduction block across ablation lines. In this study we describe the efficacy and safety of EP-guided thoracoscopic surgery for AF in patients with enlarged atria and/or prior failed catheter ablation., Methods & Results: A total of 72 patients were included. Two different approaches to EP-guided thoracoscopic surgery were implemented: epicardial or endocardial EP-guidance at the time of surgery. Residual intraoperative conduction requiring additional ablation was detected with epicardial or endocardial mapping techniques in 50% and 11%, respectively. Additional epicardial or endocardial ablation was performed until bidirectional block was confirmed. Follow-up consisted of an ECG and a 24h Holter at 3, 6 and 12 months after the procedure. A total of 57 patients (79%) had freedom of AF and were off anti-arrhythmic drugs at one year follow-up (30 paroxysmal (83%), 27 persistent AF (75%)). Adverse events occurred in 13 patients (6 major). None of our patients died and all events were reversible., Conclusion: EP-guidance of thoracoscopic surgery can be safely performed both epicardially and endocardially and is associated with a high rate of long-term maintenance of sinus rhythm in patients with enlarged atria and/or a previously failed ablation., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Background: Changes in P wave duration (PWD) and P wave area (PWA) have been described following catheter ablation for atrial fibrillation (AF). We hypothesize that video-assisted thoracoscopic pulmonary vein isolation (VATS-PVI) for AF results in decrease of PWD, PWA and P wave dispersion, which may resemble reverse electrical remodeling of the atrium after restoration of sinus rhythm., Methods: VATS-PVI consisted of PVI and ganglionic plexus ablation in 29 patients (mean age, 59 ± 7 years; 23 males; 17 paroxysmal AF) and additional left atrial lesions in patients with persistent AF. PWD and PWA were measured in ECG lead II, aVF and V2 of ECGs during sinus rhythm before, directly after, and 6 months postprocedure. P wave dispersion was derived from the 12 lead ECG., Results: Prior to VATS-PVI, PWD did not correlate with left atrial size and no difference in left atrial size was found between patients with paroxysmal or persistent AF (p = 0.27). Following VATS-PVI, PWD initially prolonged in all patients from 115 ± 4.6 ms to 131 ± 3.6 ms (p < 0.01) but shortened to 99 ± 3.2 ms after 6 months (p < 0.01). PWA was 5.60 ± 0.32 mV*ms at baseline, 6.44 ± 0.32 mV*ms post-VATS-PVI (P = NS), and 5.40 ± 0.28 mV*ms after 6 months (p = NS vs. baseline, p < 0.05 vs. post-VATS-PVI). P wave dispersion decreased in the persistent AF group from baseline 67 ± 3.3 to 64 ± 2.5 ms post-VATS-PVI (p = 0.30) and to 61 ± 3.4 ms after 6 months (p < 0.05)., Conclusions: PWD increases significantly directly after successful VATS-PVI in both groups. There was significant decrease in PWD after 6 months. Similarly, P wave dispersion decreased in the persistent group. These changes suggest an immediate procedure related effect, but the later changes may represent reverse electrical atrial remodeling following cessation of AF.

Background: In this paper we present a systematic literature overview and analysis of the first results and progress made with minimally-invasive surgery using RF energy in the treatment of AF. The minimally-invasive treatment for atrial fibrillation (AF) tries to combine the success rate of surgical treatment with a less invasive approach to surgery. It has the additional potential advantage of ganglion plexus (GP) ablation and left atrial appendage exclusion. Furthermore, additional left atrial ablation lines (ALAL) can be created in non-paroxysmal AF patients., Methods: For the search query multiple databases were used. Exclusion and inclusion criteria were applied to select the publications to be screened. All remaining articles were critically appraised and only relevant and valid articles were included in our results., Results: Twenty-three studies were included. In 15 studies GPs around the pulmonary veins were ablated. In four studies ALAL were performed. Single procedure success rate was 69% (95% CI, range 58%-78%) without antiarrhythmic drugs (AAD) and 79% (95% CI, range 71%-85%) with AAD at one year follow-up. Mortality was 0.4%, and various complications were reported (3.2% surgical, 3.2% post-surgical, 2.6% cardiac, 2.1% pulmonary, 1.7% other)., Conclusions: Twenty-three studies of minimally-invasive surgery for AF have been reviewed with success rates between that of the standard maze procedure and catheter ablation. These first combined results show promise; however, minimally-invasive surgery is still evolving, for instance by the recent inclusion of electrophysiological endpoints. Furthermore, the type of ALAL and the additional value of GP ablation have to be elucidated., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: Cardiac resynchronization therapy (CRT) reduces mortality and morbidity in patients with heart failure, diminished left ventricular function, and prolonged QRS duration. We investigated adherence to the CRT guidelines and screened for unidentified CRT candidates., Methods: Every unique patient visiting the outpatient clinic during three months was analyzed. In patients with QRS duration ≥120 ms or a paced QRS duration ≥200 ms on the electrocardiogram (ECG), left ventricular ejection fraction (LVEF), and New York Heart Association functional class were retrieved from hospital records and compared with the institutional implantable cardioverter defibrillator/pacemaker implantation database. The appropriateness of CRT indication was studied in patients who previously received CRT., Results: QRS duration was <120 ms in 2,609 out of 3,053 patients screened. LVEF was ≤35% in 28 out of 282 patients with a QRS duration ≥120 ms or a paced QRS duration ≥200 ms. Of those, 11 patients were potential CRT candidates. During follow-up, three patients received a CRT device, two patients died, one patient improved, and one refused implantation, leaving four potential CRT candidates. Forty-six patients previously implanted with a CRT device visited the outpatient clinic, of whom 42 (91.3%) fulfilled the guideline criteria. Hence, 45 out of 49 patients (91.8%) qualifying for CRT had received CRT or were implanted during follow-up, and four (8.2%) CRT candidates were unidentified., Conclusion: In a large, tertiary academic hospital, >91% of patients fulfilling guideline criteria received CRT, and 8.2% of patients were unidentified. Systematic ECG screening of every patient may prove a simple tool to detect CRT candidates who were otherwise unrecognized., (©2012, The Authors. Journal compilation ©2012 Wiley Periodicals, Inc.)

Background: Totally thoracoscopic epicardial pulmonary vein ablation is an emerging treatment of atrial fibrillation (AF). A hybrid surgical-electrophysiological procedure with periprocedural confirmation of conduction block might reduce recurrences of AF or atrial tachycardia and improve surgical success., Methods and Results: We report our joint surgical-electrophysiological approach for confirmation of conduction block across pulmonary vein ablation lines and those compartmentalizing the left atrium during totally thoracoscopic surgery. A diagnostic electrophysiology (EP) catheter positioned under the left atrium is used as reference and a custom-made multi-electrode for recording. Determination of conduction block across the pulmonary vein (PV) ablation lines requires measurement of activation time differences of milliseconds. Second, a stable reference electrogram to which to relate local activation time is required. Third, the recording electrode terminals and the inter-electrode distance should be small to prevent recording of far field activity and to allow recording of very small electrograms. We confirm entry and exit block and determine conduction block across linear ablation lines with differential pacing., Conclusion: A joint surgical-electrophysiological protocol for confirmation of conduction block across PV isolation lines and left atrial ablation lines is feasible and might prevent recurrences and further improve the success of minimally invasive surgery for AF.

Thoracoscopic surgery for atrial fibrillation (AF) is an attractive and emerging treatment modality. However, when a bleeding occurs access for hemostasis is limited. Therefore, a sternotomy might be necessary to stop the bleeding and continue the operation. We report 2 patients with a periprocedural bleeding in whom sternotomy could be prevented by tamponading the bleeding, interrupting the operation and resuming 3 weeks later. Our cases show that sternotomies can be prevented and that there is a second chance for thoracoscopic surgery for AF., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Atrial fibrillation (AF) is the most common arrhythmia in humans. The majority of patients with AF can function reasonably well on a daily basis with anti-arrhythmic drugs. A small proportion of patients with AF remain symptomatic despite anti-arrhythmic drugs. They might have an indication for invasive treatment for AF, such as endovascular catheter ablation (effective particularly in paroxysmal AF) or the Cox-Maze procedure (open heart surgery), in which the conductivity between the pulmonary veins and the left atrium is blocked. Hybrid thoracoscopic pulmonary vein isolation (VATS-PVI) is a new minimally invasive treatment for AF where the cardiothoracic surgeon and cardiologist work closely together. During this procedure the cardiologist performs electrophysiological measurements to verify whether the blockade of conductivity is successful. This approach has a success rate of 86% at a follow-up of 12 months.

Objective: To study how much the calcium scores at various phases throughout the cardiac cycle deviate from the score in the most motionless phase during retrospectively electrocardiogram (ECG)-gated multidetector row computed tomography (MDCT) of the heart and to evaluate how to optimize ECG-based tube current modulation so that errors in calcium scoring can be minimized while dose savings can be maximized., Materials and Methods: In 73 subjects with known or suspected coronary artery disease we performed retrospectively ECG-gated 64-detector row computed tomography for calcium scoring. Four subjects were excluded after scanning because of breathing artifacts or lack of coronary calcification. The scans of 69 subjects (46 men, mean age 62 +/- 6 years) were used for further analysis. Heart rate during the scan was recorded. In each patient, calcium scoring [Agatston score (AS), mass score (MS), and volume score, (VS)] was performed on 10 data sets reconstructed at 10%-intervals throughout the cardiac cycle. The most motionless phase was subjectively determined and used as the reference phase. For the score in each phase, deviation from the score in the reference phase was determined. An ECG-simulator was used to determine the amount of dose saving while scanning with dose modulation and applying diagnostic dose during 1 or several phases., Results: Mean heart rate was 63 (+/-13) beats per minute (bpm). In 51% of patients the reference phase was the 70% phase. Using the calcium score in the 70% phase (mid-diastole) instead of the reference at heart rates below 70 bpm would have induced a median score deviation of 0% [interquartile range: 0%-6% (AS, MS, and VS)] and using the calcium score in the 40% phase (end-systole) at heart rates > or =70 bpm would also have induced a median score deviation of 0% [interquartile range: 0%-7% (AS), 0%-5% (MS), and 0%-3% (VS)]. Errors in calcium scores of more than 10% occur in around 10% of subjects for all 3 scoring algorithms. Dose savings increased with lower heart rates and shorter application of diagnostic dose., Conclusions: The optimum phases for dose modulation are 70% (mid-diastole) at heart rates below 70 bpm and 40% (end-systole) at heart rates above 70 bpm. Under these conditions dose saving is maximum and a median error of 0% is found for the various calcium scoring techniques with score errors of more than 10% in around 10% of subjects.