Maze Procedure Research Articles

Outcomes and residual gap analysis after the modified cryomaze procedure performed via right minithoracotomy versus sternotomy

ObjectivesDevelopments in both technique and technology have enabled surgeons to perform the maze procedure via right minithoracotomy (RMT) to treat atrial fibrillation (AF). This study aimed to clarify the outcomes of the modified cryomaze procedure via the RMT approach compared with the sternotomy approach. MethodsThe study cohort comprised 803 consecutive patients who underwent a modified cryomaze procedure (130 via RMT and 673 via sternotomy) for paroxysmal AF and persistent AF from January 2001 to March 2022. The Gray test was applied to compare the incidence of recurrent atrial tachyarrhythmias. Additionally, residual electrical gaps were investigated in the patients who underwent additional catheter ablation for recurrent atrial tachyarrhythmias. ResultsThe respective 1-, 2-, and 3-year cumulative incidences of recurrent atrial tachyarrhythmias were 13.1%, 19.5%, and 23.1% in the RMT group, and 9.3%, 10.9%, and 12.8% in the sternotomy group (Gray test P = .036). All 31 patients with recurrent atrial tachyarrhythmias underwent additional catheter ablation, comprising 14 (10.8%) in the RMT group and 17 (2.5%) in the sternotomy group. There was a significant intergroup difference in the site of residual electrical gaps; the RMT group more frequently had residual gaps in the tricuspid annulus than the sternotomy group (6.2% vs 0.4%; P < .001). ConclusionsIn the modified cryomaze procedure via the RMT approach, ablation failure is more likely to occur at the tricuspid annulus, where the surgical field of view is relatively poor compared with the sternotomy approach. Therefore, surgical ablation should be performed with caution when the RMT approach is used.

A Narrative Literature Review Addressing Causal, Risk, and Treatment of Paroxysmal Atrial Fibrillation

This study analyzes the causal and risk factors as well as different ways of treating paroxysmal atrial fibrillation to inform healthcare professionals and physicians in order to save many lives from Atrial fibrillation related death. Factually, it is estimated that 12.1 million people in the United States will have Atrial fibrillation in 2030. In 2019, Atrial fibrillation was mentioned on 183,321 death certificates and was the underlying cause of death in 26,535 of those deaths. Also, people of European descent are more likely to have Atrial fibrillation than African Americans. Because the number of Atrial fibrillation cases increases with age and women generally live longer than men, more women than men experience Atrial fibrillation. The study adopted a narrative literature review and Boolean search technique to identify 22 researches and review articles that are related to causal and risk factors as well as different ways of treating paroxysmal atrial fibrillation. As part of the study’s findings, out of the twenty-two articles, five of the researchers, thus 22%, revealed in the literature that Heart palpitation or flutter in the chest is one of the symptoms of Atrial fibrillation. Researchers of 4 articles—thus 18% -- clearly stated in their research that one of the symptoms of Atrial fibrillation (AF) is “patient’s chest pain/pressure”. The study further revealed that some of the causes and risk factors of Symptomatic Paroxysmal Atrial Fibrillation include the following: Advancing age, High blood pressure, Obesity, Diabetes, Heart failures, European Ancestry, patient’s lifestyles such as smoking and alcohol intake, as well as Chronic kidney disease, and Hyperthyroidism. Above all, this study revealed that Medications, Heart Rate Controls, Heart Rhythm Control, Blood Clots and Stroke Prevention, Electrical Cardioversion, Cardiac Ablation, Catheter Ablation, Surgical Ablation, and Maze Procedure are some of the different options of treating or curing Symptomatic Paroxysmal Atrial Fibrillation identified in the literature. Therefore, in order for healthcare professionals and physicians to help minimize mortality rate caused by Atrial fibrillation, they should pay more attention to patients’ symptoms, the AF risk factors, and to also align them with appropriate treatment options to help save many lives across the globe. Keywords: Atrial, Fibrillation, Symptomatic, Treatment, Risk-Factors, Heart, Stroke, Paroxysmal, Cardiac, Arrhythmia, Ablation, Surgical, Maze DOI: 10.7176/JHMN/107-03 Publication date: April 30 th 2023

Surgical ablation for atrial fibrillation: impact of Diabetes Mellitus type 2

BackgroundDiabetes mellitus (DM) type 2 is an independent risk factor for atrial fibrillation (AF). Surgical ablation or "maze procedure" is an option for patients with AF undergoing concomitant or isolated cardiac surgery. The aim of this study was to evaluate the impact of DM type 2 on early and long-term outcomes of patients following surgical AF ablation.MethodsWe performed an observational cohort study in Israel’s largest tertiary care center. All data of patients who underwent surgical AF ablation, between 2006 and 2021 were extracted from our departmental database. Patients were divided into Group I (non-diabetic patients) and Group II (DM type 2 patients). We compared the two groups with respect to freedom from recurrent atrial arrhythmia, and mortality rate.ResultsThe study population included 606 patients. Group I (non-DM patients), consisting of 484 patients, and Group II (DM type 2 patients), comprised 122 patients. Patients with DM were older, had more hypertension and incidence of cerebrovascular accident (CVA)/transient ischemic attack (TIA), higher EuroSCORE (p < .05 for all), and a longer bypass time—130 ± 40 vs. 122 ± 36 min (p = 0.028). The mean follow-up duration was 39.0 ± 22.7 months. Freedom from atrial fibrillation was similar between the non-DM and DM type 2 groups after a 1-year follow-up, 414 (88.2%) vs. 101 (87.1%) (p = 0.511), after a 3-year follow-up, 360 (86.3%) vs. 84 (79.9%) (p = 0.290) and after a 5-year follow-up, 226 (74.1%) vs. 55 (71.5%) (p = 0.622) respectively. Furthermore, 1- and 3-year mortality was similar between non-DM and DM type 2 groups, 2.5% vs. 4.9%, (p = 0.226) and 5.6% vs. 10.5% (p = 0.076) respectively. 5-year mortality was higher in Group II (DM type 2 patients) compared with Group I (non-DM patients), 11.1% vs. 23.4% (p = 0.009).ConclusionSurgical ablation had a high success rate, with freedom from recurrent atrial arrhythmia at 1- 3- and 5- years follow-up in both the DM type 2 and non-DM groups. Furthermore,1- and 3-year mortality after surgical ablation was also similar in both groups. However, 5-year mortality was higher in the DM type 2 group.

Sinus node dysfunction and related permanent pacemaker implantation after major cardiac surgeries, systematic review, and meta-analysis.

There is no concise evidence or clinical guidelines regarding the incidence of sinus node dysfunction (SND) and permanent pacemaker (PPM) implantation following cardiac surgeries and their management approaches. We aim to systematically review current evidence on the prevalence of SND, PPM implantation concerning it, and its risk factors in patients undergoing cardiac surgery. Four electronic databases (Cochrane Library, Medline, SCOPUS, and Web of Science) were systematically searched for articles regarding SND after cardiovascular surgeries and reviewed by two independent researchers, and a third review in case of discrepancies. Using the random-effects model, a proportion meta-analysis was performed on data regarding PPM implantation. Subgroup analysis was performed for different interventions, and the possible effect of different covariates was evaluated using meta-regression. From the initial 2012 unique records, 87 were included in the study, and results were extracted. Pooled data from 38,519 patients indicated that the overall prevalence of PPM implantation due to SND after cardiac surgery was 2.87% (95% CI [2.09; 3.76]). The incidence of PPM implantation in the first post-surgical month was 2.707% (95% CI [1.657; 3.952]). Among the four main intervention groups, including valve, maze, valve-maze, and combined surgeries, maze surgery was associated with the highest prevalence (4.93%; CI [3.24; 6.92]). The pooled prevalence of SND among studies was 13.71% (95% CI [8.13; 20.33]). No significant relationship was observed between PPM implantation and age, gender, cardiopulmonary bypass time, or aortic cross-clamp time. Based on the present report, patients undergoing the maze and maze-valve procedures are at higher risk of post-op SND, whereas lone valve surgery had the lowest prevalence of PPM implantation. PROSPERO (CRD42022341896).

A New Frontier: No Working Port for Robotic Mitral Valve Repair.

A 61-year-old male presented via referral for mitral regurgitation and was deemed an appropriate robotic surgery candidate for complex mitral valve repair with the maze procedure and patent foramen ovale and left atrial appendage closures, using all percutaneous cannulation. We report upon the first case in the literature that describes the use of only 4 robotic ports, with no working port used.

Effects of Atrial Fibrillation Radiofrequency Ablation in Patients Aged &gt; 75 Years Undergoing Mitral Valve Surgery

Few data exist about the efficacy of radiofrequency (RF) maze procedures in elderly patients with atrial fibrillation (AF) undergoing surgery for mitral valve disease. The aim of the present investigation was to evaluate the effects of AF ablation associated with mitral valve surgery on the recovery and long-term maintenance of sinus rhythm in elderly patients aged > 75 years. Moreover, we evaluated the effects on survival. This study included 96 consecutive patients with AF (42 men and 56 women) aged > 75 years (mean age 78 ± 3) who underwent RF ablation associated with mitral valve surgery (group I). This group was compared to 209 younger patients (mean age 65 ± 8 years) treated in the same period (group II). Baseline clinical and echocardiographic characteristics were similar in the two groups. Four patients died during hospitalization, one aged > 75 years. In surviving patients at the end of the follow-up period, sinus rhythm was present respectively in 64% of the elderly and 74% of younger patients (p = 0.778). The rate of persistence of sinus rhythm without AF recurrences (38% vs. 41%, p = 0.705) was similar in the two groups. After surgery, sinus rhythm was frequently never regained in aged patients (27% vs. 20%, p = 0.231). Elderly patients more frequently needed permanent pacing and had more hospitalizations and a higher number of non-AF atrial tachyarrhythmias. At eight-year follow-up, survival was lower in older patients (48% aged > 75 vs. 79% aged < 75 years). Elderly patients had a similar long-term rate of stable sinus rhythm maintenance in comparison to younger patients after AF radiofrequency ablation associated with mitral valve surgery. However, they needed more frequent permanent pacing and had higher rates of hospitalizations and post-procedural atrial tachyarrhythmias. The effects of survival are difficult to evaluate due to the different life expectancies of the two groups.

Surgical volume and outcomes of surgical ablation for atrial fibrillation: a nationwide population-based cohort study

BackgroundAtrial fibrillation is the most common cardiac arrythmia and causes many complications. Sinus rhythm restoration could reduce late mortality of atrial fibrillation patients. The Maze procedure is the gold standard for surgical ablation of atrial fibrillation. Higher surgical volume has been documented with favorable outcomes of various cardiac procedures such as mitral valve surgery and aortic valve replacement. We aimed to determine the volume–outcome relationship (i.e., association between surgical volume and outcomes) for the concomitant Maze procedure during major cardiac surgeries.MethodsThis nationwide population-based cohort study retrieved data from the Taiwan National Health Insurance Research Database. Adult patients undergoing concomitant Maze procedures during 2010–2017 were identified; consequently, 2666 patients were classified into four subgroups based on hospital cumulative surgery volumes. In-hospital outcomes and late outcomes during follow-up were analyzed. Logistic regression and Cox proportional hazards model were used to analyze the volume–outcome relationship.ResultsPatients undergoing Maze procedures at lower-volume hospitals tended to be frailer and had higher comorbidity scores. Patients in the highest-volume hospitals had a lower risk of in-hospital mortality than those in the lowest-volume hospitals [adjusted odds ratio, 0.30; 95% confidence interval (CI), 0.15–0.61; P < 0.001]. Patients in the highest-volume hospitals had lower rates of late mortality than those in the lowest-volume hospitals, including all-cause mortality [adjusted hazard ratio (aHR) 0.53; 95% CI 0.40–0.68; P < 0.001] and all-cause mortality after discharge (aHR 0.60; 95% CI 0.44–0.80; P < 0.001).ConclusionsA positive hospital volume–outcome relationship for concomitant Maze procedures was demonstrated for in-hospital and late follow-up mortality. The consequence may be attributed to physician skill/experience, experienced multidisciplinary teams, and comprehensive care processes. We suggest referring patients with frailty or those requiring complicated cardiac surgeries to high-volume hospitals to improve clinical outcomes.Trial registration: the institutional review board of Chang Gung Memorial Hospital approved all data usage and the study protocol (registration number: 202100151B0C502).

Results of Surgical Ablation for Atrial Fibrillation in Patients with Rheumatic Heart Disease.

There is conflicting evidence regarding the success of the Maze procedure to restore sinus rhythm in patients with rheumatic heart disease. Hence, the aim of our study was to describe the results of surgical ablation for atrial fibrillation in patients with rheumatic heart disease undergoing cardiac surgery. This is a retrospective study that included adult patients with rheumatic heart disease who underwent surgical ablation for atrial fibrillation. The ablation lesions were performed using monopolar radiofrequency ablation in all patients. Fifty-seven consecutive patients were included in the study. Cox Maze IV was performed in 44 patients (77%), while left-sided surgical ablation was performed in 10 patients (17%) and pulmonary vein isolation in 3 patients (5%). The percentage of patients who were in sinus rhythm on discharge, at 1-month, at 3-months, 6-months and 12-months follow up were 56%, 54%, 52%, 56% and 46% respectively. Complete heart block occurred in 21 patients (44%), but only 15 of them (26%) required permanent pacemaker insertion. Freedom from composite endpoint of death, stroke, and readmission for heart failure was 78% at one-year follow up. Despite the suboptimal rates of sinus rhythm at the intermediate and long term follow up, surgical ablation of atrial fibrillation in patients with rheumatic heart disease should continue to be performed. Continuation of Class III antiarrhythmic medications and early intervention for recurrent atrial fibrillation is crucial to the success of this procedure and for maintenance of higher rates of sinus rhythm at intermediate and long-term follow up.

Is It Safe to Preserve Left Atrial Appendage During Maze Procedure?

The left atrial appendage (LAA) can contribute significantly to LA mechanical contraction. Nevertheless, the preventive effect of LAA occlusion during the maze procedure against cerebral infarction remains controversial. In this study, we compared the surgical, cardiac hemodynamic, and neurologic outcomes between LAA preservation and occlusion performed during the maze procedure. Between January 2015 and August 2021, 252 patients underwent the maze procedure using cryoablation at our medical center. After excluding patients according to our exclusion criteria (i.e., mechanical prosthesis implantation, preexisting LAA thrombus), LAA was preserved in 113 patients (non-occlusion group) and occluded in 75 patients (occlusion group). Outcomes were compared using propensity score matching (PSM). PSM did not reveal significant intergroup differences in baseline characteristics between the non-occlusion (n=53) and occlusion (n=53) groups. During a median follow-up of 44 months, 2 patients in the non-occlusion group (3.8%) experienced ischemic strokes. There was no significant difference in the rate of freedom from stroke (p=0.19) and major adverse cardiac events (p=0.43) between the 2 groups. Through echocardiography at 1-year follow-up, a statistically significant difference in LA mechanical contraction was observed between the non-occlusion group and occlusion group (24 of 33 [72.7%] vs. 18 of 37 [48.6%], respectively; p=0.04). In this study, preservation of the LAA during the maze procedure resulted in better LA function than LAA occlusion, with similar rates of stroke.

Long-Term Outcomes of the Maze Procedure Combined with Endoatriectomy for Patients with Calcified Left Atria.

Left atrial calcification (LAC) is found in long-lasting rheumatic valvular disease and is almost always accompanied by atrial fibrillation (AF). In the presence of LAC, endoatriectomy is required when performing the maze procedure. However, the technical feasibility of endoatriectomy and the long-term outcomes of the maze procedure in patients with LAC are uncertain. The medical records of 18 consecutive patients who underwent combined endoatriectomy and maze procedure were analyzed retrospectively. Accompanying operations were mitral valve replacement (n = 16) and commissurotomy (n = 2). There was 1 operative death from sepsis following mediastinitis. When patients were divided into "broad" (n = 11) and "limited" (n = 7) groups, with the extent of LAC either greater or less than half of the left atrium, respectively, there was no intergroup difference in postoperative complications. During follow-up (median, 11.4 years), AF recurred in 11 patients. At the last follow-up visits, electrocardiography revealed significantly fewer patients in the broad group maintaining sinus rhythm (1/11 vs 4/6, P = 0.03). The 10-year AF recurrence-free survival rates were 13.9% and 66.7% in the broad and limited groups, respectively (P = 0.01). The maze procedure combined with endoatriectomy seems technically feasible with acceptable long-term rhythm outcomes if the LAC extent is limited.

Mitral valve repair and concomitant maze procedure versus catheter ablation in the treatment of atrial functional mitral regurgitation

BackgroundTo compare mitral valve (MV) repair and concomitant maze procedure with catheter ablation in treating patients with atrial functional mitral regurgitation (AFMR).MethodsWe retrospectively identified 126 patients with AFMR from January 2012 to December 2015. Of these patients, 60 patients underwent MV repair and concomitant maze procedure, and 66 patients received catheter ablation. Patients were followed up for 7.98 ± 2.01 years. The survival, readmission of heart failure (HF), persistent atrial fibrillation (AF), persistent moderate-severe mitral regurgitation (MR) and tricuspid Regurgitation (TR), and echocardiographic data were analyzed in the follow-up. Predictors of readmission of HF were analyzed.ResultsThere was no significant difference in baseline and echocardiographic characteristics, in-hospital mortality, and other adverse events postoperatively between two groups. The surgical group was associated with lower rates of MR > 2 + grade either at discharge (P = 0.0023) or in the follow-up (P = 0.0001). There was no significant difference in the incidence of overall survival between the two groups. The surgical group was associated with a lower rate of readmission of HF and AF in the follow-up. Univariable and multivariable analysis confirmed AF at discharge, moderate-severe MR at discharge, no MV surgery, moderate-severe TR at discharge, and LA volume as predictors of readmission of HF. Both groups experienced significant reverse cardiac remodeling.ConclusionsOur results suggest that for the treatment of AFMR with persistent or long-standing persistent AF and moderate-severe MR, MV repair and concomitant maze procedure may achieve a better outcome than catheter ablation procedure.

Abstract 11825: Reduction in Muscle Mass in the Left Atrial Wall is Associated With Atrial Fibrillation

Introduction The left atrium (LA) plays a central role in the occurrence of atrial fibrillation (AF). Although many studies have demonstrated that the dilatation or alteration of the wall thickness of the LA, so called LA remodeling, was strongly associated with AF, the detailed mechanism is still unclear. Materials and Methods We retrospectively analyzed all samples of LA wall obtained during cardiac surgery in Juntendo University Hospital from 2014 to 2020. The samples were processed with Masson’s trichrome staining, then layer analysis was performed. The histological data was compared with the clinical background. Results A total of 60 patients’ samples were analyzed. The thickness of the LA wall was 1257 to 6905 μm. Layer analysis of the LA wall demonstrated that the wall thickness was not associated with the volume (R 2 = 0.0287, p = 0.098). Multiple regression analysis determined that the only factor associated with thinning of the LA was the existence of AF (p &lt;0.05). Moreover, LA wall thickness was well correlated with muscle layer thickness (R 2 = 0.744, p &lt;0.001). In addition, the patients who had AF for one year or more showed significant reduction in muscle mass compared to those with AF for less than one year (18.6% vs. 24.3%, p &lt;0.05). Among 36 patients who underwent concomitant Maze procedure during surgery, 9 had recurrent AF at 1 year after surgery. Age (p &lt;0.05), duration of AF (p &lt;0.01), and muscle area (p &lt;0.01) were detected as risk factors for recurrence. Conclusion AF was detected as the only factor associated with a reduction in the cardiac muscle mass in the LA wall. Chronic AF of more than one year’s duration enhanced the risk of reduction in the LA muscle mass. Furthermore, the reduction of the muscle mass was a comorbid factor for the recurrence of AF after the Maze procedure, along with age and duration of AF. Our results indicate that the muscle mass may be a novel predictor indicating the need for the Maze procedure.

Abstract 11717: Expression of Tumor Endothelial Marker 1 in Cardiac Fibroblasts is Associated With Atrial Fibrosis and Regulates Cell Behaviors of Cardiac Fibroblasts

Background: Tumor endothelial marker 1 (TEM1 or CD248) is a transmembrane protein that expresses in mesenchymal lineage-derived cells only during embryogenesis. Re-upregulation of TEM1 in fibroblasts has been found in hepatic fibrosis, renal fibrosis and wound healing. Atrial fibrosis plays an important role in atrial fibrillation (AF) and stroke. We evaluated TEM1 expression in atrial fibrosis and its physiological significance. Methods and Results: All data were presented as mean ± standard error. In 10 patients (pts) with AF undergoing indicated cardiac surgery and Maze procedure, left atrial (LA) appendage was excised. Immunofluorescence staining showed TEM1 expressed in LA cardiac fibroblasts (CFs) in AF pts but not in normal LA tissue purchased from the US Biomax, Inc. Sirius Red staining showed more LA fibrosis in AF than normal LA tissue (7.51±0.40% vs. 3.80±0.51%, p&lt;0.01). In AF pts, higher LA TEM1 expression detected by western blotting was associated with larger LA fibrosis. In 20 AF pts (15 men, mean age 57.5 ± 2.8 yrs) undergoing catheter ablation, LA blood samples were taken and soluble TEM1 (sTEM1) was measured by ELISA. Peak atrial longitudinal strain (PALS) measured by speckle tracking echocardiography before ablation was used as an atrial fibrosis marker. There was a significantly negative correlation of the sTEM1 levels in LA with PALS (ρ=-0.453, p&lt;0.05) indicating increased sTEM1 was associated with atrial fibrosis. In vitro study showed recombinant TEM1 protein (rTEM1) increased proliferation of cultured CFs (saline vs rTEM1 10, 50 and 100 nM, BrdU absorbance: 0.55±0.02 vs. 0.62±0.04 vs. 0.73±0.04 vs. 0.74±0.04, p&lt;0.05) and reduced starvation-induced apoptosis (cell death ELISA absorbance: 1.06±0.09 vs. 0.61±0.05 vs. 0.49±0.11 vs. 0.33±0.02, p&lt;0.05). Transwell assay showed rTEM1 induced increased CFs migration. Conclusions: The study results indicate that TEM1 upregulation in CFs is associated with atrial fibrosis and TEM1 changes the cell behaviors of CFs. Further studies are undergoing to clarify if TEM1 knockdown could alleviate atrial fibrosis.

Abstract 14225: Atrial Tachycardias After Surgical Left Atrial Appendage Exclusion

Introduction: Surgical left atrial appendage exclusion (LAA-Ex) is often performed to eliminate the need for long-term anticoagulation either as a stand-alone or concomitant procedure during cardiac surgery. A modified MAZE procedure is also usually performed during surgical LAA-Ex. Residual arrhythmogenic foci within the LAAA and/or zones of slow conduction along the stump of the LAA may contribute to recurrent atrial tachycardias (AT) after LAA-Ex. The purpose of this study was to determine the role of the LAA in recurrent atrial tachycardias (ATs) after surgical LAA-Ex. Methods: Catheter ablation (CA) was performed to eliminate ATs in 21 patients with history of AF (persistent in 18/21, 86%) 25±26 months after surgical LAA-Ex. There were 3 women; mean age was 66±9 years; and the left atrial diameter was 54±8 mms. A concomitant MAZE procedure and CA was performed previously, in 16 and 9 patients, respectively. Two patients had neither maze nor catheter ablation. There was residual blood flow into the LAA in 1/21 patient. Results: A reentrant AT involving the stump of the LAA was identified in 5/21 (24%) patients. Focal ablation on a critical isthmus within a zone of slow conduction along the LAA stump terminated AT in 3/5 patients. In the remaining 2 patients a linear lesion set from the stump to an existing line of block (left atrial roof line and anterior mitral annulus) terminated the macroreentrant AT revolving around the LAA stump. During 16±13 months of follow-up 10/21 patients (48%) remained free from recurrent ATs without antiarrhythmic drug therapy. A repeat ablation was performed in 3 patients, the mechanism of the AT was epicardial, perimitral, and multifocal but did not involve the LAA. Conclusions: After surgical LAA-Ex recurrent ATs are not uncommon and can involve the LAA stump, Although these ATs can be successfully identified and ablated, other ATs may recur and prompt additional antiarrhythmic or ablative therapy.

A Modified Maze Versus Cut-and-Sew Maze for Long-Standing Persistent Atrial Fibrillation Concomitant with Mitral Valve Surgery: A Propensity Score-Matched Cohort Study.

The cut-and-sew maze (CSM) procedure has an excellent efficacy for the elimination of long-standing persistent atrial fibrillation (AF) concomitant with mitral valve surgery. Because of the complexity and prolongation of cardiopulmonary bypass, CSM has not been widely used. The aim of this study was to examine a modified maze procedure that preserves the "cut-and-sew" procedure in the left atrium and uses cryoablation in the right atrium along with cavotricuspid isthmus. From December 2013 to December 2018, 229 patients underwent CSM, and 43 underwent the modified maze procedure during mitral valve surgery. Propensity score matching analysis was used to perform selective 1:2 ratio matching of the 43 patients undergoing the modified maze procedure with 86 patients undergoing CSM. Early operative outcomes were analysed for differences. The absence of AF recurrence without the use of anti-arrhythmic drugs was calculated at 2 years by a generalised linear model analysis. One (1.1%) early death occurred in the CSM group, and no deaths occurred in the modified maze group (p=0.722). The aortic cross-clamp durations were 76.30±8.86 minutes for the modified maze and 92.38±10.88 for the CSM procedure (p<0.001). There were no late strokes or deaths during the 2-year follow-up. The modified maze group showed similar rates of absence of AF without the use of anti-arrhythmic drugs as the CSM group within the 2 years (p=0.332). This modified maze simplifies the "cut-and-sew" procedure and reduces operating time while retaining the efficacy of CSM.

Surgery results of Cox-Maze IV procedure in treatment for atrial fibrillation combined with valve disease at Cardiovascular Center, E hospital

Introduction: Atrial fibrillation is a major cause of stroke, heart failure, and sudden death and is often associated with valve disease. The Maze procedure using the unipolar and bipolar radiofrequency devices is often combined with valvular surgery, especially mitral valve, to treat atrial fibrillation.&#x0D; Method: Cross-sectional descriptive study; 40 patientsss were treated for atrial fibrillation by COX-MAZE procedure combined with heart valve surgery in 2020-2021 at Cardiovascular Center- E Hospital.&#x0D; Result: In 40 patients, 23 males (57.5%), 17 females (42.5%), mean age 53.6 ± 8.3 (36-68) years. Mean time to dêtct atrial fibrillation 3.27 (1-9) years. 05 cases (12.5%) were preopration stroke history. Mean left atrial diameter before surgery 49.2 ± 10.1 (21-70) mm, thrombus in left atrial appendage was 8 cases (20%). All patients had mitral valve disease, accompanied by aortic valve disease 4 cases (10%) and tricuspid valve regurgitation 13 cases (32.5%). 100% of patients underwent COX-MAZE procedure. The rates of free from AF and sinus recovery after surgery 31 cases (77.5%). 02 patients (5%) sinus node dysfunction and 04 patients (10%) atrioventricular block I-II degree but they did not require temporary pacemaker placement, and recovered in 1-3 weeks.&#x0D; Conclusion: The Maze procedure by unipolar devices alone and combination with bipolar devices are effective and safe in patient atrial fibrillation combined with valvular surgery, especially mitral valve surgery.

Ventricular arrhythmias and sudden cardiac death caused by mitral valve prolapse: should we operate and when?

Abstract Background Several autopsy and observational studies have investigated the link between mitral valve prolapse (MVP) and sudden cardiac death (SCD) due to the well accepted yet rare occurrence of complex ventricular arrhythmia (VA) in this cohort. Few studies however have investigated whether arrhythmia burden and more importantly SCD are reduced following surgical correction of MVP. Purpose To investigate the impact of mitral valve surgery (MVS) (replacement or repair) on VA and SCD in patients with MVP. Methods A systematic review of the current literature was conducted using an electronic search of the PubMed database in October 2021. Studies were included if subjects had undergone mitral valve (MV) repair or replacement with documented rates of arrythmias/SCD pre- and post-intervention. Small patient numbers in individual reports precluded formal meta-analysis and results were reported on a per study basis. Results 19 identified studies (10 cohort studies, nine case studies) comprised 1322 patients with a pooled mean age of 63.4 years and 38.9% were female. 748 of the 1322 patients underwent MVS: 263 MV repair, 18 MV replacement (one with leaflet and papillary muscle excision), two MV repair with Maze procedure, 177 percutaneous transcatheter MV repair, 45 annuloplasty with or without valve repair, and in 243 cases the surgical method was not specified. Of the 10 included cohort studies, seven of the eight which investigated rates of VA post MVS concluded there was a significant reduction, while one reported the predisposition to arrythmia persisted after relieving the abnormal mechanical effects of non-ischaemic MR (75% due to MVP). One study reported a reduction in SCD post MVS. Each of the nine included case studies showed a reduction in VA post MVS. One study showed mitral annular disjunction (MAD) was independently associated with a higher risk of arrhythmic events, this link persisting with time dependent MVS although reduced compared to medical management. Conclusions The underlying mechanisms for VA and SCD associated with MVP are not completely understood, and guidelines for the surgical correction of MVP based on arrhythmic and SCD risk are lacking. This systematic review illustrates a possible reduction in VA following MVS. Further identification of patients at risk of SCD, and potential use of risk stratification algorithms, would allow for consideration of earlier management and appropriate use of implantable cardioverter-defibrillators (ICD) placement / MVS with an expected survival benefit. Funding Acknowledgement Type of funding sources: None.

The effect of cryothermic and radiofrequency Cox maze IV ablation on atrial size and function assessed by 3D echocardiography, a randomized trial. To freeze or to burn

Abstract Background The Cox maze procedures have been shown to be safe methods for restoring sinus rhythm (SR) in patient with atrial fibrillation and often performed concomitant to mitral valve (MV) surgery. Cryothermy (Cryo) and Radiofrequency (RF) are available techniques to achieve atrial linear scars. The differences between the effect of these energy sources on late left atrial (LA) reverse remodeling are not fully described. Purpose This study aims to compare the impact of Cryo and RF procedures on left atrial (LA) size and function one year after Cox-maze IV concomitant to MV surgery using 3-dimensional echocardiography (3DE). Methods Seventy-two patients with MV disease and atrial fibrillation were randomized to either Cryo (35) or RF (37) ablation. Another 33 patients were enrolled according to the protocol without concomitant ablation (NoMaze group). All patients had an echocardiogram before and one year after surgery. Results The 42 ablated patients who recovered sinus rhythm (SR) one year after surgery had comparable left and right systolic ventricular function and a mean reduction of LA size by 23% (LA volume index decreased from 66±24 to 54±13ml/m2, p=0.004). The 3DE extracted reservoir and booster function showed higher values after RF ablation compared to Cryo (37±10% vs 26±6%; p&amp;lt;0.001 resp. 18±9 vs 7±4%, p&amp;lt;0.001), while passive conduit function was comparable (24±11 vs 20±8%; p=0.17). Patients with restored SR without ablation had more preserved systolic atrial function but similar LA size reduction as those who underwent maze surgery. Conclusions SR restoration after MV surgery and maze results in LA size reduction irrespective of the energy source used. By 3DE we could show that, compared to RF maze, the extension of ablation area produced by Cryo implies a major LA structural remodeling affecting LA systolic function. The reverse size remodeling seems to be the least, the longer AF history. Funding Acknowledgement Type of funding sources: Public grant(s) – National budget only. Main funding source(s): ALF funding for clinical research-Sweden

Catheter ablation and thoracoscopic ablation in long persistent atrial fibrillation with large left atrium.

BackgroundPulmonary vein antrum isolation (PVAI) is the cornerstone of atrial fibrillation (AF) ablation, but the clinical outcomes of PVAI are unsatisfactory in patients with persistent AF and a large left atrium (LA).ObjectivesWe investigated the clinical outcomes following radiofrequency ablation (RFCA), cryoballoon ablation (CBA), and thoracoscopic maze in patients with persistent AF and a large LA.MethodsWe included patients with consecutive persistent AF who had a large LA (LA diameter >50 mm) and underwent RFCA, CBA, or thoracoscopic maze surgery. In the RFCA group, additional linear ablation was performed at the physician’s discretion. The endpoint was 12 months without recurrence of an atrial arrhythmia, including AF, atrial flutter, and atrial tachycardia, following a 90-day blanking period.ResultsWe recruited 89 persistent AF patients with a large LA who underwent RFCA (n = 32), CBA (n = 38), or the thoracoscopic maze procedure (n = 19). During the 12-month follow-up, 48 (53.9%) cases of AF recurrence were observed. There was no prognostic difference between groups (50.0% in RFCA vs. 52.6% in CBA vs. 63.2% in thoracoscopic maze, all P > 0.05). Early recurrence during the blanking period was a significant predictor of late recurrence for RFCA and CBA, but not for the thoracoscopic maze.ConclusionIn persistent AF patients with a large LA, we did not find a prognostic difference RFCA, CBA, or a thoracoscopic maze procedure in recurrence of atrial arrhythmia. Early recurrence predicted late recurrence in catheter ablation, but not in thoracoscopic maze.

Clinical benefits of concomitant surgical ablation for atrial fibrillation in patients undergoing mitral valve surgery

The maze procedure is the dominant concomitant surgery performed with mitral valve (MV) surgery in patients with atrial fibrillation (AF). Most clinical recommendations regarding the maze procedure depend on the individual maze expert centers. The purpose of this study was to evaluate the clinical benefits of the maze procedure during MV surgery in a national cohort. Using the national health claims database established by the National Health Insurance Service of South Korea, data on subjects with AF who had undergone MV surgery from 2009 to 2017 were reviewed. The outcomes of interest were mortality; occurrence of ischemic or hemorrhagic stroke; hospitalization for bleeding events; and the composite of death, cerebrovascular accident, and major bleeding. Propensity score (PS) matching was performed for baseline adjustment. Among 9501 subjects, the maze procedure was performed in 5508 (58.0%). In the PS-matched cohort (3376 pairs), the risk of the composite event was significantly lower in the maze group (hazard ratio [HR] 0.799; 95% confidence interval [CI] 0.731-0.873) than in the nonmaze group. The superiority of the maze procedure was similar for individual clinical events, including death (HR 0.795; 95% CI 0.711-0.889); ischemic stroke (HR 0.788; 95% CI 0.67-0.926); and major bleeding (HR 0.749; 95% CI 0.627-0.895), but not for hemorrhagic stroke (HR 0.984; 95% CI 0.768-1.262). In subgroup analyses of the composite events, these benefits were consistent among subjects aged ≥70 years or <70 years, surgery type (replacement vs repair), MV pathologies, and subjects with CHA2DS2-VASc score ≥4 or <4. The addition of the maze procedure during MV surgery provided protective effects in the composite outcome of interest.