Five-Year Outcomes after Off-Pump or On-Pump Coronary-Artery Bypass Grafting.

BACKGROUND: We previously reported that there was no significant difference at 30 days or at 1 year in the rate of the composite outcome of death, stroke, myocardial infarction, or renal failure between patients who underwent coronary-artery bypass grafting (CABG) performed with a beating-heart technique (off-pump) and those who underwent CABG performed with cardiopulmonary bypass (on-pump). We now report the results at 5 years (the end of the trial). METHODS: A total of 4752 patients (from 19 countries) who had coronary artery disease were randomly assigned to undergo off-pump or on-pump CABG. For this report, we analyzed a composite outcome of death, stroke, myocardial infarction, renal failure, or repeat coronary revascularization (either CABG or percutaneous coronary intervention). The mean follow-up period was 4.8 years. RESULTS: There were no significant differences between the off-pump group and the on-pump group in the rate of the composite outcome (23.1% and 23.6%, respectively; hazard ratio with off-pump CABG, 0.98; 95% confidence interval [CI], 0.87 to 1.10; P=0.72) or in the rates of the components of the outcome, including repeat coronary revascularization, which was performed in 2.8% of the patients in the off-pump group and in 2.3% of the patients in the on-pump group (hazard ratio, 1.21; 95% CI, 0.85 to 1.73; P=0.29). The secondary outcome for the overall period of the trial - the mean cost in U.S. dollars per patient - also did not differ significantly between the off-pump group and the on-pump group ($15,107 and $14,992, respectively; between-group difference, $115; 95% CI, -$697 to $927). There were no significant between-group differences in quality-of-life measures. CONCLUSIONS: In our trial, the rate of the composite outcome of death, stroke, myocardial infarction, renal failure, or repeat revascularization at 5 years of follow-up was similar among patients who underwent off-pump CABG and those who underwent on-pump CABG. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294 .).

Vasa vasorum of the failed aorto-coronary venous grafts.

PURPOSE: This study was designed to investigate the distribution of vasa vasorum in walls of failed aorto-coronary venous grafts. METHODS: Fifty-one diseased venous grafts harvested from 39 patients underwent qualitative histological evaluation. The morphology of the grade of the pathological changes and the extent of the vascularisation were examined, and related to the length of the interval between the primary surgery and the explantation. The obtained results were placed into five groups, substantially differing one from the other in morphology and vascularisation. RESULTS: The intervals between grafts implantation and explantation ranged from 1 day to 35 years. The onset of arterialization of the graft media was observed on average at 1 month after bypass implantation. During this same time period massive intimal hyperplasia and atherosclerosis occurred. Vasa vasorum proliferation from the adventitia to the outer layers of the media was first apparent between 7 and 24 months after implantation. Proliferation of the vasa vasorum throughout the entire atherosclerotic media and hyperplastic intima continued for a much longer time interval. CONCLUSION: No correlation between neoangiogenesis and age, sex or type of bypassed coronary branch was proven. Regarding the given findings, the authors believe that changes in hemodynamic conditions and endothelial trauma are primarily responsible for the development of graft disease and that vasa vasorum proliferation is only a secondary reaction to the structural changes of the graft wall. To what extent the frequently present pre-existing intimal hyperplasia of venous bypass grafts play in the development of graft disease remains questionable.

Effects of off-pump and on-pump coronary-artery bypass grafting at 1 year.

BACKGROUND: Previously, we reported that there was no significant difference at 30 days in the rate of a primary composite outcome of death, myocardial infarction, stroke, or new renal failure requiring dialysis between patients who underwent coronary-artery bypass grafting (CABG) performed with a beating-heart technique (off-pump) and those who underwent CABG performed with cardiopulmonary bypass (on-pump). We now report results on quality of life and cognitive function and on clinical outcomes at 1 year. METHODS: We enrolled 4752 patients with coronary artery disease who were scheduled to undergo CABG and randomly assigned them to undergo the procedure off-pump or on-pump. Patients were enrolled at 79 centers in 19 countries. We assessed quality of life and cognitive function at discharge, at 30 days, and at 1 year and clinical outcomes at 1 year. RESULTS: At 1 year, there was no significant difference in the rate of the primary composite outcome between off-pump and on-pump CABG (12.1% and 13.3%, respectively; hazard ratio with off-pump CABG, 0.91; 95% confidence interval [CI], 0.77 to 1.07; P=0.24). The rate of the primary outcome was also similar in the two groups in the period between 31 days and 1 year (hazard ratio, 0.79; 95% CI, 0.55 to 1.13; P=0.19). The rate of repeat coronary revascularization at 1 year was 1.4% in the off-pump group and 0.8% in the on-pump group (hazard ratio, 1.66; 95% CI, 0.95 to 2.89; P=0.07). There were no significant differences between the two groups at 1 year in measures of quality of life or neurocognitive function. CONCLUSIONS: At 1 year after CABG, there was no significant difference between off-pump and on-pump CABG with respect to the primary composite outcome, the rate of repeat coronary revascularization, quality of life, or neurocognitive function. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294.).

Off-pump or on-pump coronary-artery bypass grafting at 30 days.

BACKGROUND: The relative benefits and risks of performing coronary-artery bypass grafting (CABG) with a beating-heart technique (off-pump CABG), as compared with cardiopulmonary bypass (on-pump CABG), are not clearly established. METHODS: At 79 centers in 19 countries, we randomly assigned 4752 patients in whom CABG was planned to undergo the procedure off-pump or on-pump. The first coprimary outcome was a composite of death, nonfatal stroke, nonfatal myocardial infarction, or new renal failure requiring dialysis at 30 days after randomization. RESULTS: There was no significant difference in the rate of the primary composite outcome between off-pump and on-pump CABG (9.8% vs. 10.3%; hazard ratio for the off-pump group, 0.95; 95% confidence interval [CI], 0.79 to 1.14; P=0.59) or in any of its individual components. The use of off-pump CABG, as compared with on-pump CABG, significantly reduced the rates of blood-product transfusion (50.7% vs. 63.3%; relative risk, 0.80; 95% CI, 0.75 to 0.85; P<0.001), reoperation for perioperative bleeding (1.4% vs. 2.4%; relative risk, 0.61; 95% CI, 0.40 to 0.93; P=0.02), acute kidney injury (28.0% vs. 32.1%; relative risk, 0.87; 95% CI, 0.80 to 0.96; P=0.01), and respiratory complications (5.9% vs. 7.5%; relative risk, 0.79; 95% CI, 0.63 to 0.98; P=0.03) but increased the rate of early repeat revascularizations (0.7% vs. 0.2%; hazard ratio, 4.01; 95% CI, 1.34 to 12.0; P=0.01). CONCLUSIONS: There was no significant difference between off-pump and on-pump CABG with respect to the 30-day rate of death, myocardial infarction, stroke, or renal failure requiring dialysis. The use of off-pump CABG resulted in reduced rates of transfusion, reoperation for perioperative bleeding, respiratory complications, and acute kidney injury but also resulted in an increased risk of early revascularization. (Funded by the Canadian Institutes of Health Research; CORONARY ClinicalTrials.gov number, NCT00463294.).

Double-gap-in-roof reentrant tachycardia following surgical thoracoscopic atrial fibrillation ablation.

A case of macro-reentrant tachycardia associated with a box lesion after thoracoscopis left atrial surgical atrial fibrillation (AF) ablation yet to be described. The goal was to clarify the mechanisms and electrophysiological characteristics of this type of tachycardia. A patient was admitted for an EP study following surgical thoracoscopic AF ablation (box lexion formation by right-sided Cobra thoracoscopic ablation). Thoracoscopic ablation was done as the first step of the hybrid ablation approach to the persistent AF; the second step was the EP study. At the EP study, he presented with incessant regular tachycardia (cycle length of 226 ms). An EP study with conventional, 3D activation and entrainment mapping was done to assess the tachycardia mechanism. Two conduction gaps in the superior line (roofline) between the superior pulmonary veins were discovered. The tachycardia was successfully treated with a radiofrequency application near the gap close to the left superior pulmonary vein; however, following tachycardia termination, pulmonary vein isolation was absent. A second radiofrequency application, close to the roof of the right superior pulmonary, vein closed the gap in the box and led to the isolation of all 4 pulmonary veins. No atrial tachycardia recurred during the 6-month follow-up. Conduction gaps in box lesion created by thoracospcopic ablation can present as a novel type of man-made tachycardia after surgical ablation of atrial fibrillation. Activation and entrainment mapping is necessary for an accurate diagnosis.

Comparison of cardiac surgery with left atrial surgical ablation vs. cardiac surgery without atrial ablation in patients with coronary and/or valvular heart disease plus atrial fibrillation: final results of the PRAGUE-12 randomized multicentre study.

AIMS: Surgical ablation procedure can restore sinus rhythm (SR) in patients with atrial fibrillation (AF) undergoing cardiac surgery. However, it is not known whether it has any impact on long-term clinical outcomes. METHODS AND RESULTS: This multicentre study randomized 224 patients with AF scheduled for valve and/or coronary surgery: group A (left atrial surgical ablation, n = 117) vs. group B (no ablation, n = 107). The primary efficacy outcome was the SR presence (without any AF episode) during a 24 h electrocardiogram (ECG) after 1 year. The primary safety outcome was the combined endpoint of death/myocardial infarction/stroke/renal failure at 30 days. A Holter-ECG after 1 year revealed SR in 60.2% of group A patients vs. 35.5% in group B (P = 0.002). The combined safety endpoint at 30 days occurred in 10.3% (group A) vs. 14.7% (group B, P = 0.411). All-cause 1-year mortality was 16.2% (A) vs. 17.4% (B, P = 0.800). Stroke occurred in 2.7% (A) vs. 4.3% (B) patients (P = 0.319). No difference (A vs. B) in SR was found among patients with paroxysmal (61.9 vs. 58.3%) or persistent (72 vs. 50%) AF, but ablation significantly increased SR prevalence in patients with longstanding persistent AF (53.2 vs. 13.9%, P < 0.001). CONCLUSION: Surgical ablation improves the likelihood of SR presence post-operatively without increasing peri-operative complications. However, the higher prevalence of SR did not translate to improved clinical outcomes at 1 year. Further follow-ups (e.g. 5-year) are warranted to show any potential clinical benefit which might occur later.

Rationale and design of the coronary artery bypass grafting surgery off or on pump revascularization study: a large international randomized trial in cardiac surgery.

BACKGROUND: Uncertainty remains regarding the benefits and risks of the technique of operating on a beating heart (off pump) for coronary artery bypass grafting (CABG) surgery versus on-pump CABG. Prior trials had few events and relatively short follow-up. There is a need for a large randomized, controlled trial with long-term follow-up to inform both the short- and long-term impact of the 2 approaches to CABG. METHODS: We plan to randomize 4,700 patients in whom CABG is planned to undergo the procedure on pump or off pump. The coprimary outcomes are a composite of total mortality, myocardial infarction (MI), stroke, and renal failure at 30 days and a composite of total mortality, MI, stroke, renal failure, and repeat revascularization at 5 years. We will also undertake a cost-effectiveness analysis at 30 days and 5 years after CABG surgery. Other outcomes include neurocognitive dysfunction, recurrence of angina, cardiovascular mortality, blood transfusions, and quality of life. RESULTS: As of May 3, 2011, CORONARY has recruited >3,884 patients from 79 centers in 19 countries. Currently, patient's mean age is 67.6 years, 80.7% are men, 47.0% have a history of diabetes, 51.4% have a history of smoking, and 34.4% had a previous MI. In addition, 20.9% of patients have a left main disease, and 96.6% have double or triple vessel disease. CONCLUSIONS: CORONARY is the largest trial yet conducted comparing off-pump CABG to on-pump CABG. Its results will lead to a better understanding of the safety and efficacy of off-pump CABG.

Local and systemic application of tranexamic acid in heart valve surgery: a prospective, randomized, double blind LOST study.

The study was performed to examine a possible augmentation of systemic administration of tranexamic acid by the additional topical application during heart valve surgery in the post-aprotinin era. One-hundred patients were enrolled in the study and all the patients were given tranexamic acid intravenously. The participants were randomized into two groups (A, n = 49; B, n = 51), and before commencing the sternal suturing, the study solution (group A: 250 ml of normal saline + tranexamic acid 2.5 g, placebo group B: 250 ml of normal saline) was poured into the pericardial cavity. The cumulative blood loss (geometric means [95% confidence intervals]) 4 h after the surgery was 86.1 [56.1, 132.2] ml in group A, and 135.4 [94.3, 194.4] in group B, test for equality of geometric means P = 0.107, test for equality of variances P = 0.059. Eight hours after the surgery, the blood loss was 199.4 [153.4, 259.2] ml in group A, 261.7 [205.1, 334.0] ml in group B, P = 0.130 and P = 0.050, respectively. Twenty-four hours postoperatively the blood loss was 504.2 [436.0, 583.0] ml in group A, 569.7 [476.0, 681.7] ml in group B, P = 0.293 and P = 0.014, respectively. The proportion of patients transfused postoperatively by fresh frozen plasma differed significantly between the two study groups (group A: n = 21, group B: n = 36, P = 0.008). Our hypothesis is supported by a significant difference in the inter-group variance of blood loss and the proportion of patients requiring fresh frozen plasma; however evident differences in mean postoperative blood loss were not statistically significant.

Decreased apoptosis following successful ablation of atrial fibrillation.

OBJECTIVES: Increased apoptotic processes in tissue samples from hearts in atrial fibrillation (AF) have been previously documented in animals. Whether the restoration of sinus rhythm is associated with decreased apoptosis is not known. The aim of the present study was to establish whether successful epicardial ablation of AF leads to changes in the concentration of serum markers of apoptosis. METHODS: Twenty-five patients with AF were prospectively studied. All underwent epicardial isolation of pulmonary veins. The success of the ablation was assessed clinically and with 3 Holter recordings. Blood samples were drawn before surgery, and at 3 and 6 months after. Serum concentrations of Fas (apoptosis-stimulating fragment) and TRAIL (tumor necrosis factor-related apoptosis-inducing ligand) were measured using ELISA. RESULTS: AF was successfully ablated in 15 patients (SR group). In the other 10 patients (AF group), AF recurred during follow-up. Neither group differed with respect to age, sex, left ventricular ejection fraction, or preoperative concentrations of measured molecules. While Fas decreased in successfully ablated patients, there was no change in the Fas concentration in the AF group. Similarly, the concentrations of TRAIL decreased in the SR group, but remained unchanged in the AF group. CONCLUSION: The ablation of AF is associated with decreased serum markers for apoptosis.

Rivaroxaban, Aspirin, or Both to Prevent Early Coronary Bypass Graft Occlusion: The COMPASS-CABG Study.

BACKGROUND: Patients with recent coronary artery bypass graft (CABG) surgery are at risk for early graft failure, which is associated with a risk of myocardial infarction and death. In the COMPASS (Cardiovascular OutcoMes for People Using Anticoagulation StrategieS) trial, rivaroxaban 2.5 mg twice daily plus aspirin 100 mg once daily compared with aspirin 100 mg once daily reduced the primary major adverse cardiovascular events (MACE) outcome of cardiovascular death, stroke, or myocardial infarction. Rivaroxaban 5 mg twice daily alone did not significantly reduce MACE. OBJECTIVES: This pre-planned substudy sought to determine whether the COMPASS treatments are more effective than aspirin alone for preventing graft failure and MACE after CABG surgery. METHODS: The substudy randomized 1,448 COMPASS trial patients 4 to 14 days after CABG surgery to receive the combination of rivaroxaban plus aspirin, rivaroxaban alone, or aspirin alone. The primary outcome was graft failure, diagnosed by computed tomography angiogram 1 year after surgery. RESULTS: The combination of rivaroxaban and aspirin and the regimen of rivaroxaban alone did not reduce the graft failure rates compared with aspirin alone (combination vs. aspirin: 113 [9.1%] vs. 91 [8.0%] failed grafts; odds ratio [OR]: 1.13; 95% confidence interval [CI]: 0.82 to 1.57; p = 0.45; rivaroxaban alone vs. aspirin: 92 [7.8%] vs. 92 [8.0%] failed grafts; OR: 0.95; 95% CI: 0.67 to 1.33; p = 0.75). Compared with aspirin, the combination was associated with fewer MACE (12 [2.4%] vs. 16 [3.5%]; hazard ratio [HR]: 0.69; 95% CI: 0.33 to 1.47; p = 0.34), whereas rivaroxaban alone was not (16 [3.3%] vs. 16 [3.5%]; HR: 0.99, CI: 0.50 to 1.99; p = 0.98). There was no fatal bleeding or tamponade within 30 days of randomization. CONCLUSIONS: The combination of rivaroxaban 2.5 mg twice daily plus aspirin or rivaroxaban 5 mg twice daily alone compared with aspirin alone did not reduce graft failure in patients with recent CABG surgery, but the combination of rivaroxaban 2.5 mg twice daily plus aspirin was associated with similar reductions in MACE, as observed in the larger COMPASS trial. (Cardiovascular OutcoMes for People Using Anticoagulation StrategieS [COMPASS]; NCT01776424).

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.

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.

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.

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.

Electrophysiological findings after surgical thoracoscopic atrial fibrillation ablation.

BACKGROUND: Hybrid ablation (a combination of thoracoscopic epicardial ablation and catheter ablation) has become a new technique for atrial fibrillation treatment. OBJECTIVE: The goal of this study was to evaluate the success and electrophysiological follow-up after using the COBRA Fusion device to deliver a circumferential lesion set anterior to the pulmonary veins in an attempt to isolate the posterior left atrium (box isolation). METHODS: Surgical ablation was carried out via a thoracoscopic approach using the COBRA Fusion radiofrequency catheter. An electrophysiology study was done 2-3 months later to verify box isolation (and to complete it, if needed) and to perform right-sided isthmus ablation. Fat thickness along the presumed box lesion line was measured using preprocedural computed tomography. RESULTS: Thirty patients (mean age 60.0 ± 11.6 years; 22 men; 8 with long-standing persistent AF and 22 with persistent atrial fibrillation) were enrolled. The duration of the EP study was 216.3 ± 64.2 minutes. Box isolation, based on the EP study, was complete in 12 patients (40%) and incomplete in 18 patients (60%). Successful box isolation was achieved with catheter ablation in 16 of 18 patients (89%). A total of 39 gaps in these 16 patients were identified. Typical gap locations were the anterior-superior part of the superior pulmonary veins and the roofline. Fat thickness along the roofline was substantially higher than that along the inferior line (4.58 ± 1.61 mm vs 2.37 ± 0.76 mm; P < .001). CONCLUSION: There is a relatively low rate of complete isolation using the COBRA catheter ablation system. The superior line and anterior parts of superior pulmonary veins have most conduction gaps.

Values of osteoprotegerin in aortic valve tissue in patients with significant aortic stenosis depend on the existence of concomitant coronary artery disease.

INTRODUCTION: Calcific aortic valve stenosis (CAVS) is a serious clinical problem. The strongest predictor of CAVS progression is the amount of calcium in the aortic valve. The pathogenesis of CAVS is largely consistent with the pathogenesis of atherosclerosis; however, about 50% of patients with CAVS do not exhibit significant atherosclerosis. Cardiovascular calcification is currently considered an actively regulated process, in which the important role is attributed to the RANKL/RANK/OPG (receptor activator of nuclear factor κB ligand/RANK/osteoprotegerin) axis. We measured OPG levels in the tissue of calcified, stenotic aortic valves in relation to the presence or absence of coronary artery disease (CAD). MATERIALS AND METHODS: Aortic valve samples were collected from 105 patients with calcified, mainly severe aortic stenosis, who were divided into two groups according to the presence of CAD. In Group A (n=44), there were normal coronary artery findings, while in Group B (n=61), there was angiographically demonstrated >50% stenosis of at least one coronary artery. The control Group C (n=21) consisted of patients without aortic stenosis and with normal angiographic findings on coronary arteries. RESULTS: The highest tissue concentrations of OPG [median (pmol/L), 25th-75th percentile] were found in Group A [6.95, 3.96-18.37], which was significantly different compared to the other two groups (P=.026 and .001, respectively). The levels of OPG in Group B [4.15, 2.47-9.16] and in Group C [2.25, 1.01-5.08] did not differ significantly (P=.078); however, the lowest concentrations of OPG were found in Group C. Neither age nor gender in our study had effect on tissue levels of OPG (P=.994 for gender; P=.848 for age). CONCLUSION: Calcified and narrowed aortic valves, compared to the normal valves, were accompanied by a change in tissue concentrations of OPG, which is, in addition, dependent on the presence or absence of CAD. The highest tissue concentrations of OPG in our work were found in patients with significant aortic stenosis without concomitant CAD.

Off-pump versus on-pump coronary artery bypass grafting surgery in high-risk patients: PRAGUE-6 trial at 30 days and 1 year.

AIMS: Off-pump coronary artery bypass graft surgery (OPCAB) is an established alternative to on-pump surgical revascularization. Previous studies in patients with low or intermediate risk showed no significant differences between off-pump and on-pump surgical revascularization. The aim of this study was to compare the two techniques in patients with high operative risk. METHODS: PRAGUE-6 is a prospective randomized single-center study of 206 patients, with an additive EuroSCORE ≥ 6, scheduled for isolated coronary surgery: Group A - on-pump (n = 108) versus Group B - off-pump (n = 98). The primary outcome was a combined endpoint of all-cause deaths, stroke, myocardial infarction, or renal failure requiring new hemodialysis, within 30 days and 1 year after randomization. All data were analyzed using the "intention-to-treat" principle. RESULTS: Early postoperative myocardial infarction was detected in 12.1% (A) vs. 4.1% (B) of patients (P = 0.048, hazard ratio 0.32, 95% CI 0.11-0.99). There was a significantly higher incidence of primary combined end-point in group A (20.6% vs. 9.2%, P = 0.028, HR 0.41, 95% CI 0.19-0.91) in the first 30 days, but not after 1 year (30.8% vs. 21.4%, P = 0.117, HR 0.65, CI 0.37-1.12). CONCLUSION: Off-pump surgical revascularization in patients with high operative risks can significantly reduce the incidence of major postoperative complications during the first 30 days. There was no statistically significant difference in the incidence of these complications after 1 year.