Sequential hybrid ablation vs. surgical CryoMaze alone for treatment of atrial fibrillation: results of multicentre randomized controlled trial.

AIMS: Data on the hybrid atrial fibrillation (AF) treatment are lacking in patients with structural heart disease undergoing concomitant CryoMaze procedures. The aim was to assess whether the timely pre-emptive catheter ablation would achieve higher freedom from AF or atrial tachycardia (AT) and be associated with better clinical outcomes than surgical ablation alone. METHODS AND RESULTS: The trial investigated patients with non-paroxysmal AF undergoing coronary artery bypass grafting and/or valve repair/replacement with mandatory concomitant CryoMaze procedure who were randomly assigned to undergo either radiofrequency catheter ablation [Hybrid Group (HG)] or no further treatment (Surgery Group). The primary efficacy endpoint was the first recurrence of AF/AT without class I or III antiarrhythmic drugs as assessed by implantable cardiac monitors. The primary clinical endpoint was a composite of hospitalization for arrhythmia recurrence, worsening of heart failure, cardioembolic event, or major bleeding. We analysed 113 and 116 patients in the Hybrid and Surgery Groups, respectively, with a median follow-up of 715 (IQR: 528-1072) days. The primary efficacy endpoint was significantly reduced in the HG [41.1% vs. 67.4%, hazard ratio (HR) = 0.38, 95% confidence interval (CI): 0.26-0.57, P < 0.001] as well as the primary clinical endpoint (19.9% vs. 40.1%, HR = 0.51, 95% CI: 0.29-0.86, P = 0.012). The trial groups did not differ in all-cause mortality (10.6% vs. 8.6%, HR = 1.17, 95%CI: 0.51-2.71, P = 0.71). The major complications of catheter ablation were infrequent (1.9%). CONCLUSION: Pre-emptively performed catheter ablation after the CryoMaze procedure was safe and associated with higher freedom from AF/AT and improved clinical outcomes.

Prediction of post-operative atrial fibrillation in patients after cardiac surgery using heart rate variability.

PURPOSE: Post-operative atrial fibrillation (PoAF) occurs in ~ 30% of patients after cardiac surgery. The etiology of PoAF is complex, but a disbalance in autonomic systems plays an important role. The goal of this study was to assess whether pre-operative heart rate variability analysis can predict the risk of PoAF. METHODS: Patients without a history of AF with an indication for cardiac surgery were included. Two-hour ECG recordings one day before surgery was used for the HRV analysis. Univariate and multivariate logistic regression, including all HRV parameters, their combination, and clinical variables, were calculated to find the best predictive model for post-operative AF. RESULTS: One hundred and thirty-seven patients (33 women) were enrolled in the study. PoAF occurred in 48 patients (35%, AF group); the remaining 89 patients were in the NoAF group. AF patients were significantly older (69.1 ± 8.6 vs. 63.4 ± 10.5 yrs., p = 0.002), and had higher CHA2DS2-VASc score (3 ± 1.4 vs. 2.5 ± 1.3, p = 0.01). In the multivariate regression model, parameters independently associated with higher risk of AF were pNN50, TINN, absolute power VLF, LF and HF, total power, SD2, and the Porta index. A combination of clinical variables with HRV parameters in the ROC analysis achieved an AUC of 0.86, a sensitivity of 0.95, and a specificity of 0.57 and was more effective in PoAF prediction than a combination of clinical variables alone. CONCLUSION: A combination of several HRV parameters is helpful in predicting the risk of PoAF. Attenuation of heart rate variability increases the risk for PoAF.

Sequential hybrid ablation versus surgical CryoMaze alone for treatment of atrial fibrillation (SurHyb Trial): a protocol of the multicentre randomized controlled trial.

BACKGROUND: Atrial fibrillation is common in patients with structural heart disease who are undergoing cardiac surgery. Surgical CryoMaze has been shown to be an effective treatment in several trials, but success rates have varied considerably, between 47-95%. The sequential hybrid approach, combining surgical CryoMaze followed by radiofrequency catheter ablation, can achieve high freedom from atrial arrhythmias. However, in patients with concomitant surgical atrial fibrillation treatment, data comparing the hybrid approach to CryoMaze alone are lacking. METHODS: The SurHyb study was designed as a prospective, open-label, multicentre randomized trial. Patients with non-paroxysmal atrial fibrillation who were scheduled for coronary artery bypass grafting or valve repair/replacement were randomized to either surgical CryoMaze alone or surgical CryoMaze followed by radiofrequency catheter ablation 3 months post-surgery. The primary outcome measure was arrhythmia-free survival without class I or III antiarrhythmic drugs, which has been evaluated using implantable cardiac monitors. CONCLUSIONS: This is the first randomized study that compares concomitant surgical CryoMaze alone with the staged hybrid surgical CryoMaze followed by catheter ablation, in patients with non-paroxysmal atrial fibrillation using rigorous rhythm monitoring. The results may contribute to the optimization of the treatment in patients undergoing concomitant CryoMaze for atrial fibrillation.

Changes in cognitive function after thoracoscopic and catheter ablation for atrial fibrillation.

BACKGROUND: Comparative data regarding the effect of percutaneous and thoracoscopic ablation of atrial fibrillation (AF) on cognitive function are very limited. The aim of the study was to determine and compare the effect of both types of ablations on patient cognitive functions in the mid-term. METHODS: Patients with AF indicated for ablation procedure were included. Forty-six patients underwent thoracoscopic, off-pump ablation using the COBRA Fusion radiofrequency system, followed by a catheter ablation three months afterward (Hybrid group). A comparative cohort of 53 AF patients underwent pulmonary vein isolation only (PVI group). Neuropsychological examinations were done before and nine months after the surgical or catheter ablation procedure. Neuropsychological testing comprised 13 subtests of seven domains, and the results were expressed as post-operative cognitive dysfunction (POCD) nine months after the procedure. RESULTS: Patients in both groups were similar with respect to the baseline clinical characteristics; only non-paroxysmal AF was more common in the hybrid group (98% vs. 34%). Major POCD was present in eight (17.4%) of hybrid patients versus three (5.7%) of PVI patients (p = 0.11), combined (major/minor) worsened cognitive decline was present in 10 (21.7%) hybrid patients versus three (5.6%) PVI patients (p = 0.034). On the other hand, combined (major/minor) improvement was present in 15 (32.6%) hybrid patients versus nine (16.9%) patients in the PVI group (p = 0.099). CONCLUSION: Hybrid ablation, a combination of thoracoscopic and percutaneous ablation, is associated with a higher risk of cognitive decline compared to sole percutaneous ablation.

Partial upper sternotomy for aortic valve replacement provides similar mid-term outcomes as the full sternotomy.

Background: Minimally invasive aortic valve replacement via upper partial sternotomy (MiniAVR) provides very good short-term results and delivers certain advantages in the postoperative course. There is limited data regarding the mid-term mortality and morbidity following this minimally invasive surgery. Methods: We provide a retrospective analysis of the patients, undergoing MiniAVR versus full sternotomy (FS) for aortic valve replacement with biological prosthesis. As the primary combined end-point the combination of death, stroke, and rehospitalization within 3 years postoperatively was defined. Data have been collected from National Cardiac Surgery Registry and insurance companies. Results: Two hundred consecutive patients with aortic valve replacement (100 ministernotomy in MiniAVR group and 100 full sternotomy in FS group) with biological prosthesis were included in this study. Ministernotomy had longer cross-clamp and bypass times (median difference 6.5 min, P=0.005, and 8.5 min, P=0.002 respectively). Patients operated via upper partial sternotomy had a lower postoperative bleeding [300 mL (IQR, 290) vs. 365 mL (IQR, 207), P=0.031]. There was no difference in the 3-year mortality (14% vs. 11%, P=0.485). The mean number of readmission 3 years after surgery per capita was almost the same in both groups (1.65 vs. 1.60, P=0.836). Median time to the first readmission was longer in the MiniAVR group (difference 8.9 months). The incidence of combined end-point during 3 years postoperatively in both groups was not statistically different (P=0.148), as well as readmissions from cardio-vascular reasons (subhazard ratio 0.90, P=0.693). Conclusions: Upper partial sternotomy can be performed safely for aortic valve replacement, without increased risk of death, stroke or re-admission in 3 years postoperatively.

Silent strokes after thoracoscopic epicardial ablation and catheter ablation for atrial fibrillation: not all lesions are permanent on follow-up magnetic resonance imaging.

BACKGROUND: Invasive treatments for atrial fibrillation (AF) pose a risk of ischemic stroke due to periprocedural brain embolization, which may be manifest or silent. The primary aim of our study was to compare the rate of silent strokes after percutaneous catheter-based and thoracoscopic epicardial ablation for AF. The secondary aim was to evaluate the development of silent strokes over time. METHODS: We included 39 subjects (aged 64.1±8.9 years) treated for persistent symptomatic AF with thoracoscopic ablation and 30 subjects (aged 64.1±10.5 years) treated for paroxysmal or persistent symptomatic AF with catheter ablation. Subjects underwent brain MRI before and early after the ablation, moreover, the surgical group underwent late MRI 6 months after therapy. On early MRI, the presence of silent strokes and their number and size were evaluated. On late MRI, transformation of previously-detected acute ischemic lesions into chronic infarction or their reversibility were assessed. RESULTS: Initially, different chronic ischemic findings were found in 64% of patients from the surgical group and in 70% from catheter group. Early MRI results: acute ischemic lesions were detected in 2 (6.7%) subjects (overall 3 lesions sized <5 mm) in the catheter group and in 17 (43.6%) subjects in surgical group. Most subjects in the surgical group showed multiple lesions (88%); 195 lesions were detected, a median 6 (IQR 8) lesions per case. Eighty-two percent of lesions were <5 mm, 12% 5-10 mm, 5% 10-30 mm, and 2% were large territorial ischemia. Only 1 case was symptomatic, the rest were silent strokes. On late MRI, 53.5% of all acute lesions were reversible. Lesions <5 mm were reversible in 63.1% of cases, lesions 5-10 mm were reversible in 21.7% and all lesions larger than 10 mm persisted. In 29.4% of patients all acute ischemic lesions were fully reversible. CONCLUSIONS: Periprocedural silent strokes were significantly more common after thoracoscopic epicardial ablation compared to catheter ablation considering both the number of affected patients and number of lesions. The majority of acute ischemic brain lesions were small, up to 5 mm in diameter, roughly half of which were reversible. Reversibility of acute ischemic lesions decreased with size. However, in 29.4% of affected patients, all lesions were fully reversible.

The Efficacy and Safety of Hybrid Ablations for Atrial Fibrillation.

OBJECTIVES: This study sought to comprehensively determine the procedural safety and midterm efficacy of hybrid ablations. BACKGROUND: Hybrid ablation of atrial fibrillation (AF) (thoracoscopic ablation followed by catheter ablation) has been used for patients with nonparoxysmal AF; however, accurate data regarding efficacy and safety are still limited. METHODS: Patients with nonparoxysmal AF underwent thoracoscopic, off-pump ablation using the COBRA Fusion radiofrequency system (Estech) followed by a catheter ablation 3 months afterward. The safety of the procedure was assessed using sequential brain magnetic resonance and neuropsychological examinations at baseline (1 day before), postoperatively (2-4 days for brain magnetic resonance imaging or 1 month for neuropsychological examination), and at 9 months after the surgical procedure. Implantable loop recorders were used to detect arrhythmia recurrence. Arrhythmia-free survival (the primary efficacy endpoint) was defined as no episodes of AF or atrial tachycardia while off antiarrhythmic drugs, redo ablations or cardioversions. RESULTS: Fifty-nine patients (age: 62.5 ± 10.5 years) were enrolled, 37 (62.7%) were men, and the mean follow-up was 30.3 ± 10.8 months. Thoracoscopic ablation was successfully performed in 55 (93.2%) patients. On baseline magnetic resonance imaging, chronic ischemic brain lesions were present in 60.0% of patients. New ischemic lesions on postoperative magnetic resonance imaging were present in 44.4%. Major postoperative cognitive dysfunction was present in 27.0% and 17.6% at 1 and 9 months postoperatively, respectively. The probability of arrhythmia-free survival was 54.0% (95% CI: 41.3-66.8) at 1 year and 43.8% (95% CI: 30.7-57.0) at 2 years. CONCLUSIONS: The thoracoscopic ablation is associated with a high risk of silent cerebral ischemia. The midterm efficacy of hybrid ablations is moderate.

Left Atrial Appendage Occlusion during Cardiac Surgery to Prevent Stroke.

BACKGROUND: Surgical occlusion of the left atrial appendage has been hypothesized to prevent ischemic stroke in patients with atrial fibrillation, but this has not been proved. The procedure can be performed during cardiac surgery undertaken for other reasons. METHODS: We conducted a multicenter, randomized trial involving participants with atrial fibrillation and a CHA2DS2-VASc score of at least 2 (on a scale from 0 to 9, with higher scores indicating greater risk of stroke) who were scheduled to undergo cardiac surgery for another indication. The participants were randomly assigned to undergo or not undergo occlusion of the left atrial appendage during surgery; all the participants were expected to receive usual care, including oral anticoagulation, during follow-up. The primary outcome was the occurrence of ischemic stroke (including transient ischemic attack with positive neuroimaging) or systemic embolism. The participants, research personnel, and primary care physicians (other than the surgeons) were unaware of the trial-group assignments. RESULTS: The primary analysis population included 2379 participants in the occlusion group and 2391 in the no-occlusion group, with a mean age of 71 years and a mean CHA2DS2-VASc score of 4.2. The participants were followed for a mean of 3.8 years. A total of 92.1% of the participants received the assigned procedure, and at 3 years, 76.8% of the participants continued to receive oral anticoagulation. Stroke or systemic embolism occurred in 114 participants (4.8%) in the occlusion group and in 168 (7.0%) in the no-occlusion group (hazard ratio, 0.67; 95% confidence interval, 0.53 to 0.85; P = 0.001). The incidence of perioperative bleeding, heart failure, or death did not differ significantly between the trial groups. CONCLUSIONS: Among participants with atrial fibrillation who had undergone cardiac surgery, most of whom continued to receive ongoing antithrombotic therapy, the risk of ischemic stroke or systemic embolism was lower with concomitant left atrial appendage occlusion performed during the surgery than without it. (Funded by the Canadian Institutes of Health Research and others; LAAOS III ClinicalTrials.gov number, NCT01561651.).

High resolution respirometry to assess function of mitochondria in native homogenates of human heart muscle.

Impaired myocardial bioenergetics is a hallmark of many cardiac diseases. There is a need of a simple and reproducible method of assessment of mitochondrial function from small human myocardial tissue samples. In this study we adopted high-resolution respirometry to homogenates of fresh human cardiac muscle and compare it with isolated mitochondria. We used atria resected during cardiac surgery (n = 18) and atria and left ventricles from brain-dead organ donors (n = 12). The protocol we developed consisting of two-step homogenization and exposure of 2.5% homogenate in a respirometer to sequential addition of 2.5 mM malate, 15 mM glutamate, 2.5 mM ADP, 10 µM cytochrome c, 10 mM succinate, 2.5 µM oligomycin, 1.5 µM FCCP, 3.5 µM rotenone, 4 µM antimycin and 1 mM KCN or 100 mM Sodium Azide. We found a linear dependency of oxygen consumption on oxygen concentration. This technique requires < 20 mg of myocardium and the preparation of the sample takes <20 min. Mitochondria in the homogenate, as compared to subsarcolemmal and interfibrillar isolated mitochondria, have comparable or better preserved integrity of outer mitochondrial membrane (increase of respiration after addition of cytochrome c is up to 11.7±1.8% vs. 15.7±3.1%, p˂0.05 and 11.7±3.5%, p = 0.99, resp.) and better efficiency of oxidative phosphorylation (Respiratory Control Ratio = 3.65±0.5 vs. 3.04±0.27, p˂0.01 and 2.65±0.17, p˂0.0001, resp.). Results are reproducible with coefficient of variation between two duplicate measurements ≤8% for all indices. We found that whereas atrial myocardium contains less mitochondria than the ventricle, atrial bioenergetic profiles are comparable to left ventricle. In conclusion, high resolution respirometry has been adapted to homogenates of human cardiac muscle and shown to be reliable and reproducible.

Improvement in the quality of life of patients with persistent or long-standing persistent atrial fibrillation after hybrid ablation.

BACKGROUND: Hybrid ablation (i.e., a combination of a thoracoscopic surgical ablation followed by a catheter ablation) is a treatment option for patients with non-paroxysmal atrial fibrillation (AF). Despite its promising efficacy, it is a surgical procedure with a relatively high risk of complications that could affect the quality of life (QoL) of patients, even when sinus rhythm is restored. OBJECTIVE: To describe changes in the QoL of patients with non-paroxysmal AF before and after a hybrid ablation. METHODS: Patients after hybrid ablation for persistent or long-standing persistent AF were prospectively studied. Follow-up visits were scheduled at 1, 3, 6, 9, and 12 months. The maintenance of SR was assessed using 1-week Holter recordings at 6 and 12 months and 24-h Holter recordings at 3 and 9 months, or via an implantable loop recorder. QoL was assessed using the Atrial Fibrillation Effect on Quality-of-life (AFEQT) and the EuroQoL-5Dimensions (EQ-5D) questionnaires before and 12 months after ablation. RESULTS: Seventy-five patients (49 men, age 62.9 ± 8.45 years, 48 (64%) with long-standing persistent AF) were enrolled. Fifty-two (69.3%, SR group) were AF-free during the 12-month follow-up, 16 (21.3%, PAROX group) had only paroxysms of AF after ablation, and 7 (9.3%, PERM group) were on rate control due to permanent AF reoccurrence. The AFEQT score increased significantly in the SR group from 59.9 ± 19.4 to 91.4 ± 10.8 (p < 0.001), and in the PAROX group from 58.8 ± 19.0 to 81.5 ± 14.1 (p = 0.002) but remained unchanged in the PERM group (44.6 ± 7.5 vs. 47.4 ± 5.5, p = 0.24). The EQ-5D score significantly decreased in the descriptive part (from 7.90 ± 2.61 to 6.64 ± 1.90, p = 0.0001) and increased on the visual analog scale (from 63.56 ± 19.11 to 79.30 ± 16.9, p < 0.0001) in the SR group. In the PAROX group, no significant change was present on either the descriptive part (p = 0.3) or in the visual analog scale (p = 0.48). Similarly, no significant changes were present on either the descriptive part (p = 0.93) or the visual analog scale (p = 0.4) in the PERM group. CONCLUSION: The QoL of patients with non-paroxysmal AF and patients with AF paroxysms, after successful hybrid ablation, improved significantly in patients with SR. No significant improvement was present in patients on rate control after an unsuccessful ablation.

Five-year outcomes in cardiac surgery patients with atrial fibrillation undergoing concomitant surgical ablation versus no ablation. The long-term follow-up of the PRAGUE-12 Study.

BACKGROUND: The long-term effect of concomitant surgical ablation (SA) on clinical outcomes in an unselected population of patients has not been sufficiently reported in randomized studies. OBJECTIVE: The aim of this study was to assess clinical outcomes of the SA after 5 years of follow-up. METHODS: The PRAGUE-12 study was a prospective, randomized clinical trial assessing cardiac surgery with ablation for AF vs cardiac surgery alone. Patients with AF who were also indicated for cardiac surgery (coronary artery disease [CAD], valve surgery) were randomized to SA or control (no ablation) group. All patients were followed for 5 years. The primary endpoint was a composite of cardiovascular death, stroke, hospitalization for heart failure, or severe bleeding. Secondary endpoint was a recurrence of AF. RESULTS: A total of 207 patients were analyzed (SA group = 108 patients, control group = 99 patients). Both groups were similar relative to important clinical characteristics except for CAD, which was more common in the control group. Cumulative incidence curves showed a higher incidence of the primary endpoint in the control group (P = .024, Gray's test). However, after adjusting for all covariables, the difference between groups was not significant (subhazard ratio [SHR] 0.69 [0.47-1.02], P = .068). The incidence of stroke and AF recurrences were significantly reduced in the SA group, and remained significant even after adjustment for all covariables, including CAD (stroke: SHR 0.32 [0.12-0.84], P = .02, AF recurrences: SHR 0.44 [0.31-0.62], P < .001). CONCLUSIONS: Concomitant SA of AF is associated with a greater likelihood of maintaining sinus rhythm and a decreased risk of stroke.

Residual echocardiographic and computed tomography findings after thoracoscopic occlusion of the left atrial appendage using the AtriClip PRO device.

OBJECTIVES: Thoracoscopic occlusion of the left atrial appendage (LAA) has become a routine part of thoracoscopic ablation for the treatment of atrial fibrillation (AF). Evaluation of residual findings of the occluded LAA by echocardiography has yet to be described. METHODS: Patients with AF indicated for hybrid ablation (thoracoscopic procedure followed by catheter ablation) were enrolled in this study. LAA was occluded as a routine part of the thoracoscopic procedure. Follow-up transoesophageal echocardiography was performed at the end of the procedure, 2-5 days and 2-3 months after the procedure (before the endocardial stage). The residual pouches of the LAA were measured in the mitral valve view (30-110°) and in the perpendicular view. The depth of the residual pouch was measured from the ostial plane (connecting the Coumadin ridge and the circumflex artery) to the deepest part of the residuum. The volume of the residual pouch and the distance from the circumflex artery to the proximal and the distal ends of the AtriClip were measured using computed tomography. RESULTS: Forty patients were enrolled in this study. The success rate for the occlusion of the LAA, assessed on transoesophageal echocardiography 2-5 days after surgery, was 97.5%. Regarding the residual findings, no reperfused LAAs were found, and only residual stumps remained. The depth of the stump was 12.9 ± 5.9 mm, the area was 2.2 ± 1.1 cm2, and the volume was 3.6 ± 1.9 ml (all data are shown as mean ± standard deviation). CONCLUSIONS: The occlusion of the LAA using an AtriClip PRO device was a clinically safe procedure with high efficacy and was associated with the presence of a small residual pouch after occlusion. Clinical trial registration: NCT02832206.

Two-staged hybrid ablation of non-paroxysmal atrial fibrillation: clinical outcomes and functional improvements after 1 year.

OBJECTIVES: Hybrid ablation of atrial fibrillation (AF) is a promising treatment strategy; however, data regarding its efficacy and safety are still limited. METHODS: Patients with non-paroxysmal AF were enrolled. First, a thoracoscopic, epicardial isolation of pulmonary veins and the left atrial posterior wall ('box lesion') was performed; a novel unipolar/bipolar radiofrequency device was used. Moreover, in 12 patients enrolled thereafter, the left atrial appendage was occluded. Electrophysiological evaluation and catheter ablation were performed 2-3 months later, with the goal of verifying or completing (if needed) the box lesion and ablation of the ganglionated plexi and the cavotricuspid isthmus. Outcomes were assessed using 1-week and 24-h Holter monitoring, repeated echocardiography and laboratory measurements. RESULTS: Thirty-eight patients (13 persistent and 25 long-standing persistent AF) were enrolled with a mean AF duration of 33 ± 32.9 months. The procedure was successfully completed in 35 patients; 3 patients underwent only the surgical part because of a postoperative left atrial appendage thrombus (2 patients) and perioperative stroke (1 patient). After 6 months, 30 (86%) patients were arrhythmia-free, whereas 80% were also off antiarrhythmics. After 1 year, 28 (82%) patients were arrhythmia-free, 79% were off anti-arrhythmics and 47% were off anticoagulation treatment. Four (10.5%) serious postoperative complications occurred, including 1 stroke, 1 right phrenic nerve palsy and 2 pneumothoraxes with a need for drainage. Significant improvements were observed in echocardiographic, functional and serological parameters. CONCLUSIONS: Hybrid ablation is an effective treatment strategy for patients with persistent or long-standing persistent AF. Over 80% of patients were arrhythmia-free 1 year after the procedure. Sinus rhythm restoration was accompanied by improvements in functional, echocardiographic and serological markers.

Midterm outcomes of two-staged hybrid ablation of persistent and long-standing persistent atrial fibrillation using the versapolar epicardial surgical device and subsequent catheter ablation.

PURPOSE: Hybrid ablation of atrial fibrillation (AF) is a promising treatment strategy for patients with non-paroxysmal AF, although, data regarding mid-term outcomes are limited. METHODS: Patients with persistent or long-standing persistent AF were enrolled. Initially, a thoracoscopic, right-sided, epicardial ablation was performed, with a goal of creating a box lesion on the posterior wall of the left atrium; a novel versapolar radiofrequency (RF) catheter was used. In patients enrolled later, occlusion of the left atrial appendage was also performed. An endocardial procedure was performed 2-4 months later, with the goal of confirming/completing the box lesion and ablating the ganglionated plexi and cavotricuspid isthmus. Efficacy was assessed using multiple 24-h and 1-week Holter monitoring. Analysis was performed to search for variables associated with procedure's failure. RESULTS: Forty-one patients (14 persistent and 27 long-standing persistent AF) were enrolled with a mean AF duration of 33.5 ± 33.1 months. Mean follow-up was 507.2 ± 201.1 days (180-731). At the last follow-up visit, 27(65%) patients were arrhythmia-free, without anti-arrhythmics or need for re-ablation. Additional 4 patients (9.8%) were in sinus rhythm (SR) following re-ablation of postprocedural peri-mitral flutter and 4 (9.8%) were in SR on anti-arrhythmics. Longer periods of preoperative AF were independently associated with worse arrhythmia-free survival (p = 0.015). Serious postoperative complications occurred in 3 (7.3%) patients; only 1 (2.4%) patient had clinical consequences after 6 months. CONCLUSIONS: Hybrid ablation of non-paroxysmal AF using a novel, versapolar RF device yields promising mid-term results. Better arrhythmia-free survival rates were found in AF patients with shorter AF duration.

Risk of Intraatrial Thrombi After Thoracoscopic Ablation in Absence of Heparin and Appendage Closure.

BACKGROUND: Catheter and surgical ablation of atrial fibrillation (AF) can be associated with a risk of thromboembolic events. The goal of this study was to assess optimal anticoagulation management during thoracoscopic ablation of AF. METHODS: Fifty-two patients with persistent or long-standing persistent AF underwent hybrid ablation consisting of thoracoscopic ablation followed by electrophysiologic (EP) evaluation and consecutive ablation if indicated. The thoracoscopic ablation was performed using three different anticoagulation protocols: (1) without periprocedural heparin and without occlusion of the left atrial appendage; (2) with periprocedural heparin but without left atrial appendage occlusion; and (3) with periprocedural heparin and left atrial appendage occlusion. Transesophageal echocardiography (TEE) was obligatorily used to screen for intraatrial thrombi before the surgical and EP procedure and before hospital discharge for patients in protocols 2 and 3. RESULTS: In group 1 (n = 20), 1 patient (5%) had a postoperative stroke with persistent neurologic deficit, and 6 other patients (30%) had a new thrombus in the left atrial appendage seen on the pre-EP TEE. In group 2 (n = 6), 3 left atrial appendage thrombi occurred (50%; 2 on predischarge TEE and 1 on pre-EP TEE). In group 3 (n = 26), no intracardiac thrombi were found on predischarge and pre-EP TEE, and there were no strokes in this group of patients, namely, the rates of thrombus or stroke were significantly reduced when compared with groups 1 and 2 (p = 0.001). CONCLUSIONS: Thoracoscopic ablation of AF can be associated with a risk of left atrial appendage thrombus formation and possibly also stroke. With administration of heparin during the ablation, followed by occlusion of the left atrial appendage as a part of the procedure, this risk can be effectively reduced.

The future of hybrid ablation: an emerging need for an anticoagulation protocol for thoracoscopic ablation.

The midterm efficacy of hybrid ablation of atrial fibrillation (AF) reported in recent papers is about 70% in terms of sinus rhythm maintenance without antiarrhythmic drugs. Bearing in mind that the majority of patients enrolled are patients with persistent and long-standing persistent AF, the reported efficacies seem to be very good. Despite the high efficacies, safety remains a critical issue in hybrid, and especially thoracoscopic ablations. The frequency of complications during thoracoscopic ablations is more than 10% in the majority of reports. Most are short-term with no sequelae (such as pneumothorax or pneumonia); however, life-threatening complications have also been described, e.g., a sternotomy in response to a laceration of the left atrium (LA). One of the most serious ablation complications is stroke. The rate of strokes, which has been reported during or shortly after thoracoscopic ablation, seems to be higher than the rate reported after catheter ablation. This is especially true in papers describing thoracoscopic ablations that were not immediately followed by a catheter ablation. A possible explanation is differences in anticoagulation management during the two procedures. During catheter endocardial procedures, a standard anticoagulation protocol exists and is routinely applied; however, there is no such set of recommendations for anticoagulation during the thoracoscopic-phase of an ablation. It seems probable that, in many cases, no anticoagulation is used during thoracoscopic ablations. Moreover, whatever anticoagulation protocol is used during thoracoscopic ablations often goes unreported. A discussion about the best anticoagulation strategy during thoracoscopic ablation is urgently needed. In the future, standards of anticoagulation during thoracoscopic ablation should be clearly reported, just as they are now for catheter ablations.

The absence of effect of ganglionated plexi ablation on heart rate variability parameters in patients after thoracoscopic ablation for atrial fibrillation.

BACKGROUND: Hybrid ablation [thoracoscopic ablation (TA) of atrial fibrillation (AF) followed by catheter ablation (CA)] is an increasingly common method of the treatment for patients with AF. The aim of this study was to assess the response to ganglionated plexi (GP) ablation in patients with a previous TA (i.e., to assess whether TA had resulted in damage to the GP. Heart rate variability (HRV) was used as a marker of the autonomic response. METHODS: Twenty AF patients underwent pulmonary vein isolation (PVI) plus GP ablation (GP group) and 18 AF patients underwent CA including GP ablation as a part of hybrid ablation (i.e., all patients had undergone a previous TA; Hybrid group). In each group, a 5 min electrocardiogram (ECG) obtained before and after the CA were analyzed. Time and frequency domain parameters were evaluated. RESULTS: Vagal responses (VR) during CA were observed in 12 (60%) patients in the GP group; however, in the Hybrid group, VR was not observed in any of the patients during CA. The change in normalized power in the low frequency (LF) component and the ratio between the LF and high frequency (LF/HF ratio) components of the HRV spectra, before and after ablation, were statistically significant in the GP group (3.3±2.6 before vs. 1.8±1.9 after ablation) but unchanged, before or after CA, in the Hybrid group. CONCLUSIONS: GP ablation in patients subsequent to TA has a little influence on HRV parameters, which could be explained by GP damage during the preceding TA.

Prognostic impact and change of concomitant mitral regurgitation after surgical or transcatheter aortic valve replacement for aortic stenosis.

BACKGROUND: Significant aortic stenosis (AS) is frequently associated with mitral regurgitation (MR) of varying degrees. We sought to assess the change in MR grade after the aortic valve procedure, to find predictors of MR improvement and finally to determine the prognostic impact of persistent MR. METHODS: We retrospectively analyzed a group of 101 AS patients who underwent aortic valve replacement (AVR) or transcatheter aortic valve implantation (TAVI) at our institution between January 2007 and March 2014 and who presented with MR grade 2 or higher on preoperative echocardiogram - 35 patients underwent an isolated AVR, 18 underwent TAVI, and the rest underwent a combined procedure, which included coronary artery bypass grafting. The mean follow-up was 28.5±21 months. RESULTS: MR improved significantly after the procedures (2.4±0.5 vs. 1.9±0.9, p<0.001) and a decline in the severity of MR was observed regardless of etiology (degenerative/post-rheumatic, functional/ischemic, combined) without significant changes between groups (p=0.667). Downgrading of MR severity was associated with improvement in ejection fraction (p=0.021) and reduction in the size of cardiac chambers, especially the left atrium (left atrial diameter, p<0.001). None of the preoperatively evaluated factors (severity of AS, MR etiology, ejection fraction, cardiac chamber dimensions, coronary artery disease, and New York Heart Association functional class) was a significant predictor of MR improvement. Persistence of higher degrees of MR was associated with a more frequent need for cardiovascular hospitalization, while the survival rate 3 years after procedure was not affected (p=0.146). CONCLUSIONS: In the majority of AS patients, an aortic valve procedure leads to reduction in coexistent MR. A significant decrease in the severity of MR in our study was observed regardless of etiology and preoperative grade of MR. Persistence of higher degrees of MR was associated with increased patient morbidity.

Treatment of stand-alone atrial fibrillation with a right thoracoscopic approach employing a microwave or monopolar radiofrequency energy source: long-term results.

OBJECTIVES: Minimally invasive surgery for atrial fibrillation (AF) has rapidly evolved recently. The long-term efficacy of most of these procedures is poorly known. METHODS: Between 2006 and 2010, 38 drug-resistant, symptomatic patients with stand-alone AF underwent unilateral, thoracoscopic, off-pump ablation. The mean age was 60 ± 8.2 (range 42-75) years and the mean AF duration was 46 ± 62 (range 3-240) months. Sixteen patients (42%) had paroxysmal, 9 (24%) had persistent and 13 (34%) had long-standing persistent AF. A box lesion was created using a microwave (26 patients) or monopolar radiofrequency (12 patients) system. Patients were prospectively followed with repeat electrocardiograms (ECGs) and ECG Holters. Additional catheter ablation was offered to patients with recurrence of arrhythmia. RESULTS: All procedures were completed as planned with one conversion to sternotomy, zero mortality and minimal in-hospital complications. The mean follow-up duration was 70 ± 19 (range 20-88) months. Arrhythmia-free survival rates after the procedure were 50, 44.4, 24.1 and 10.8% at 6, 12, 36 and 60 months, respectively, with most recurrences in the first 6 months. Twelve patients underwent additional catheter ablation(s); from the last intervention, 75% of them were in sinus rhythm (SR) with a mean follow-up of 31 ± 23 (range 4-86) months. Overall, at the end of follow-up, only 3 patients were still in SR without any arrhythmia recurrence. Major complications (cerebral, peripheral embolism or bleeding) occurred in 5 patients. CONCLUSIONS: Unilateral, thoracoscopic AF ablation is safe and technically feasible. However, the results of the microwave and monopolar radiofrequency devices were less than satisfactory, with a gradual decline in arrhythmia-free survival over a very long-term follow-up.