CryoMaze Procedure Research Articles

Successful Surgical Treatment of Atrial Fibrillation, Mitral Regurgitation, and Aortic Root Aneurysm in a Patient With Classical Type Ehlers-Danlos Syndrome

Herein, we present an unusual case of a 48-year-old patient with Ehlers-Danlos syndrome (classic type) with multiple cardiovascular pathologies, including mitral regurgitation, a dilated aortic root, and chronic atrial fibrillation. A complex mitral valve repair, modified cryo-Maze procedure, and aortic valve-sparing operation (reimplantation) were performed, which were further complicated by the patient's fragile tissues. The patient was discharged on postoperative day 10 in good health with normal mitral and aortic valve function. We believe that this is the first report of such an extensive cardiac procedure in a patient with Ehlers-Danlos syndrome.

Long-term results and reliability of cryothermic ablation based maze procedure for atrial fibrillation concomitant with mitral valve surgery☆

Atrial fibrillation (AF) is the common arrhythmia associated with valvular heart disease, and surgical ablation to treat AF is reported to contribute to eliminate mortality and morbidity. We report our clinical results of cryomaze procedure obtained in over 10-years' experience. Since 1998 when we introduced cryoablation to reduce cut-and-sew line, 268 patients (145 males and 123 females, mean age of 61.2-year old) underwent cryomaze procedure concomitant with mitral valve surgery. We retrospectively obtained preoperative and follow-up data from medical records, and investigated survival rate, freedom from permanent AF recurrence rate and risk factors for recurrence. Three in-hospital deaths were noted (1.1%), and 243 patients (91.8% of survived patients) were discharged restoring to sinus rhythm. Pacemaker implantation during hospital stay was required in 12 cases (4.5%). There were five late deaths, and 5- and 10-year cumulative survival rates were both 93.2%. Multivariate analysis revealed that huge left atrium, longer history of AF and smaller f-wave in electrocardiogram were the independent risk factors for recurrence of permanent AF. Older age and re-do cardiac surgery were not significant factors. Cryoablation based maze procedure for AF adjunct to mitral valve surgery is an effective and long-term promising solution for restoring sinus rhythm. Patient selection criterion concerning left atrial size, duration of AF and f-wave voltage might be reasonable to improve the results.

Intermediate-term Outcomes of Surgical Atrial Fibrillation Correction with the CryoMaze Procedure

Few studies have reported long-term outcomes of surgical atrial fibrillation (AF) correction. We perform the Cox-Maze III lesion set with argon-powered cryoenergy (CryoMaze procedure) on all patients with AF presenting for cardiac operations. This study reports long-term clinical results and heart rhythm status. Between July 2002 and November 2005, 119 consecutive patients underwent surgical AF correction with the CryoMaze procedure. Mitral valve disease was the primary indication for operation in 66%. AF was continuous in 65%. Rhythm assessment was with 2-week continuous electrocardiographic (ECG) monitoring in 75% of patients and by noncontinuous ECG in the remainder. Median follow-up was 3.2 years and was 98% complete. There was one hospital (0.8%) death. Survival at 3 years was 84%. One perioperative stroke resolved completely. No late strokes occurred. In 4 of 119 patients (4 (3.4%), pacemakers were inserted during the index hospitalization. Median length of stay was 7 days. Overall freedom from AF more than 3 years after operation was 60%. Among patients with preoperative intermittent AF, 85% (28 of 33) were in normal sinus rhythm, and 47% (27 of 58) with continuous AF were in normal sinus rhythm (p < 0.001). CryoMaze AF correction is safe and is associated with a very low risk of stroke. Rates of normal sinus rhythm at more than 3 years postoperatively were high for patients with intermittent AF and acceptable for those with continuous AF. This experience supports wider application of the CryoMaze to all patients with AF who need cardiac operations.

Surgical treatment of atrial fibrillation using cryothermy in patients undergoing mitral valve surgery

Surgical treatment of atrial fibrillation (AF) using a variety of energy sources and a mixture of lesion sets has become an important adjunct in patients undergoing cardiac surgery. We retrospectively analyzed prospectively collected data of 141 patients with a history of AF (mean duration of AF 35+/-39 months; intermittent AF: n=72; 51%; permanent AF: 69 (49%)) who underwent a left-sided Cryomaze procedure in conjunction with mitral valve (MV) surgery between January 2003 and September 2006. Freedom from AF was 77% at discharge and 87% at a mean follow-up of 305+/-195 days with a decreasing rate of AF during the first 3-9 months from 13% to 9% and an increase beyond the first year (29% at 2 years). Predictors of failed Cryomaze in multivariate analysis were left atrial size >50 mm (OR=5.7), AF at surgery (OR=5.0) and cardiac reoperation (OR=3.4), whereas preoperative beta-blocker treatment was a predictor of success (OR=0.2). Our data suggest that a left-sided Cryomaze procedure effectively restores sinus rhythm in patients with AF undergoing MV surgery. The success rate should not be evaluated immediately postoperatively because there is a steady increase in the rate of patients with freedom from AF in the first year. It appears, however, that there is a higher rate of recurrence during later follow-up.

Beating Heart Direct Left Atrial Access Balloon Cryoablation: Safety and Efficacy of Pulmonary Vein Isolation in an Ovine Model

: Clinical experience with endocardial cryoablation for the surgical treatment of atrial fibrillation has demonstrated safety and efficacy. Direct access to the left atrium via a thoracoscopic or pericardial approach with a balloon-tipped cryoablation catheter might facilitate endocardial cryoablation on the beating heart. We investigated the ability of a novel cryoballoon to produce endocardial pulmonary vein ostial cryolesions on the beating heart in a large-animal model. : Six sheep underwent small left thoracotomy. A 10.5F catheter with a 23-mm cryoballoon was inserted directly into the left atrium under fluoroscopic and intracardiac echo (ICE) guidance. Cryoablation of the pulmonary vein ostia was performed. Animals were killed at 14 days. Pulmonary venous electrical isolation was assessed immediately before the animals were killed. : All animals survived balloon cryoablation with no periprocedural complications. Balloon occlusion was well tolerated hemodynamically, with minimal change in blood pressure (-4 ± 6 mm Hg systolic BP) and no change in heart rate. ICE demonstrated an absence of intracardiac air or ice embolization during ablation. Mean balloon temperature was -67 ± 8°C. All animals were neurologically intact after the procedure. Five of 6 (83%) veins exhibited circumferential exit block. Phrenic nerve function was intact in all animals. On gross inspection, all lesions were circumferential and continuous without evidence of endocardial thrombus. Pathology confirmed circumferential transmurality in all treated veins. : Direct left atrial access cryoballoon ablation was effective for isolating pulmonary veins. This technology may be an important component of a minimally invasive beating heart CryoMaze procedure for the treatment of atrial fibrillation.

Transaortic Delivery of the Transmitral Lesion in a Complete Maze Procedure

A 68-year-old hypertensive diabetic woman with chronic atrial fibrillation presented with progressive congestive symptomatology. She was diagnosed with severe aortic stenosis, moderate mitral regurgitation, and critical right coronary artery stenosis. In addition to coronary revascularization and bioprosthetic aortic valve replacement, she underwent a mitral valve repair and a complete cryoMaze procedure through a transaortic approach. This technique obviates a separate left atriotomy for the mitral repair and Maze procedure. It affords excellent exposure, while reducing cross clamp and cardiopulmonary bypass time as well as avoiding the potential sequelae of bleeding and traction injuries resulting from a left atriotomy.

New Ablation Techniques for Atrial Fibrillation and the Minimally Invasive Cryo-Maze Procedure in Patients with Lone Atrial Fibrillation

Atrial fibrillation (AF) is associated with significant morbidity and mortality. Medical management is often palliative but new ablation techniques have enabled curative approaches. Catheter-based ablation has limited success, whilst surgical approaches are widely applicable with favourable results. The minimally invasive Cryo-Maze (MICM) replicates the lesions of the Cox-Maze procedure using cryotherapy. We present our retrospective review of all Cryo-Maze procedures performed at East Carolina University, from October 2003 to January 2006, with analysis of all MICM's for lone AF, via a small right inframammary incision. A total of 41 patients (29 male, 12 female, age 61.6+/-9.7 years) with lone AF underwent an MICM as a primary operation. There were no deaths or early or late strokes. At discharge 36 patients (87.8%) were in sinus. At six weeks, this ratio had increased to 90.2% (37/41). The rate of SR continued to improve and for those out three months, the rate increased to 92.7% (38/41). At six months, 87.2% (34/39) were in SR. SR was seen in 20/23 patients with follow-up beyond one year (87.0%). In conclusion, surgical ablation techniques that replicate the Cox-Maze procedure are associated with high rates of sinus rhythm beyond one year, with wide application. AF is a curable condition, using a combination of catheter-based and surgical approaches. Newer surgical ablation devices allow minimally invasive approaches.

Surgical treatment of chronic atrial fibrillation combined with rheumatic mitral valve disease: effects of the cryo-maze procedure and predictors for late recurrence

The aim of this study was to evaluate the effects of the modified maze procedure using cryoablation for treating chronic atrial fibrillation (AF) associated with rheumatic mitral valve disease and to assess the risk factors for late failure of sinus rhythm restoration. Between March 2000 and June 2004, 170 consecutive patients, who underwent the modified maze procedure using cryoablation concomitant with mitral valve surgery for atrial fibrillation associated with rheumatic mitral valve disease, were divided into two groups based on the type of right-sided maze: the modified Cox-maze III (CM group, n=93) and modified Kosakai-maze (KM group, n = 77) procedures. The postoperative and mid-term follow-up results were analyzed and compared between the two groups. Both univariate and multivariate analyses were used to assess the risk factors for late recurrence of atrial fibrillation. There were three in-hospital deaths, including two in the CM group (2.2%) and one in the KM group (1.3%), and there were no significant differences in the incidence of postoperative complications between the two groups. The cardiopulmonary bypass and aortic cross-clamp times were significantly shorter in the KM group than the CM group. At discharge, the sinus rhythm rate was 70% in the CM group and 74% in the KM group (p = 0.55). Follow-up was completed in 97% of the patients, with a mean time of 26.6+/-15.2 months. At the latest follow-up, one death occurred in the CM group (0.6%). Sinus rhythm was documented in 141 (84%) out of all the patients, including 76 (84%) in the CM group and 65 (86%) in the KM group (p=0.72). The 4-year actuarial survival free from stroke was 90.3+/-5.9% for the CM group and 96.4+/-3.5% for the KM group (p = 0.68), and 4-year event-free survival was 81.2+/-7.4% for the CM group and 96.4+/-3.5% for the KM group (p = 0.078). Using a multivariate analysis, a left atrial dimension >65 mm (p = 0.011) and repair for rheumatic mitral valve disease (p = 0.038) were independent risk factors for a late recurrence of AF. The modified maze procedures using cryoablation are safe and effective in treating chronic atrial fibrillation associated with rheumatic mitral valve disease.

The impact of mitral valve surgery combined with maze procedure☆

Recent studies indicated that successful maze procedure for atrial fibrillation (AF) adjunct to mitral valve surgery provided a lower incidence of stroke and recurrence of AF. The purpose of this study is to review the 13-year experience of these combined procedures and to identify the risk factors and late outcomes of successful maze procedures compared to failed maze procedures. At a single institution, 521 consecutive patients underwent combined maze procedures with mitral valve replacements or valvuloplasties. Three kinds of maze techniques were primarily used: Cox-maze III, Kosakai maze, and cryo-maze procedure. Three months after the operation, 394 patients were in sinus rhythm (Group S) while the remaining 116 patients were in continuous or intermittent AF (Group F), excluding 11 early death patients. Risk factors for Group F were determined by the analysis of all patient demographics. Survival, freedom from stroke, cardiac events, and AF recurrence were analyzed. The proportion of the patients without any other simultaneous procedures was greater in Group S (41% vs 29%, P = 0.02). The distributions of mitral valve surgery and maze procedure techniques were similar in these two groups. A left atrium larger than 70 mm [hazard ratio (HR) = 2.6; 95% confidence interval range 1.04-6.3, P = 0.043], preoperative AF history longer than 10 years (HR = 8.2; 4.5-15.1, P < 0.001) and f-wave voltage in V1 smaller than 0.1 mV (HR = 6.2; 5.0-15.2, P < 0.001) were determined to be risk factors for unsuccessful maze procedures. All the results of Cox proportional hazards models showed superiority in Group S; actuarial survival rates (HR = 2.7; 1.04-7.0, P = 0.035), freedoms from stroke (HR = 3.0; 1.1-8.1, P = 0.003) and cardiac events (HR = 4.3; 2.9-6.1, P < 0.001). Freedom from AF recurrence rate was 98.4% at 5 years and 81.0% at 12 years in Group S, and 73.0% and 60.1% in overall patients. Patients with successful maze procedures resulted in higher survival rate, greater freedom from stroke and cardiac events. The large left atrium, small f-wave, and long AF duration were significant risk factors for failed maze procedures, suggesting that earlier surgical interventions would result in superior results in mitral valve surgery combined with maze procedure.

A Multi-institutional Experience With the CryoMaze Procedure

A Multi-institutional Experience With the CryoMaze Procedure

Excellent Results with a Left Atrial Cryomaze Procedure for the Surgical Treatment of Atrial Fibrillation

Excellent Results with a Left Atrial Cryomaze Procedure for the Surgical Treatment of Atrial Fibrillation

Robot-Assisted Minimally Invasive Cryo-Maze Procedure For Treatment Of Lone Atrial Fibrillation. Results From An Initial Series

Robot-Assisted Minimally Invasive Cryo-Maze Procedure For Treatment Of Lone Atrial Fibrillation. Results From An Initial Series

A Multi-Institutional Experience With the CryoMaze Procedure

The Cox Maze III operation remains the gold standard for the surgical treatment of atrial fibrillation (AF). We report our experience using a flexible argon-powered metal cryoprobe for creation of the complete Cox-Maze III lesion set in patients with AF (the CryoMaze operation). Beginning July 2002, 38 patients underwent the CryoMaze operation. Two patients had isolated CryoMaze procedures, whereas 36 patients had the CryoMaze performed in combination with coronary, valvular, or aortic surgery. All patients had electrocardiographic follow-up. Atrial fibrillation was continuous in 79%. Mean duration of AF before operation was 48 months. There were no complications related to the use of cryoenergy. There was 1 hospital death (2.6%) and no late deaths. At a mean follow-up of 12 months, 35 of 37 patients (95%) were in normal sinus rhythm. One patient required pacemaker implantation 3 months after surgery, and 1 patient refused follow-up. There have been no early or late thromboembolic events. The CryoMaze operation reliably cures atrial fibrillation at medium term follow-up, with rates identical to those reported for the classic Cox-Maze III operation.

The Effect of Cryo-Maze Procedure on Early and Intermediate Term Outcome in Mitral Valve Disease: Case Matched Study

The maze procedure is an effective way to treat atrial fibrillation (AF) associated with mitral valve disease. In a last several years, cryoablation was substituted for atrial incision in many reports to simplify the maze procedure. However, there has been no comparative study to delineate the feasibility of the use of cryoablation. We compared the early and intermediate-term results of the maze procedure including pulmonary venous isolation from the left atrium using cryoablation (CM) with our conventional (Kosakai) maze procedure (KM) including encircling incision around the orifices of pulmonary veins. One hundred and 10 pairs of patients were matched in the age, left atrial dimension >70 mm, duration of AF >0 years, previous cardiac surgery, mechanical valve implantation and concomitant aortic valve procedures. CM required significantly shorter cardiopulmonary bypass time (186+/-56 minute versus 214+/-47 minute, P=0.001) and aortic cross-clamp time (134+/-43 minute versus 144+/-37 minute, P=0.03) than KM with less chest tube drainage (590+/-353 mL versus 745+/-618 mL, P=0.02) for 12 hours after operation. The sinus rhythm restoration rate in CM group (85.4%) was comparable with KM group (86.4%) at discharge. In the late results, the actuarial freedom from recurrence of sustained AF at 3 years in CM group (97.7%) was not significantly (P=0.11) different from that in KM group (90.4%). The actuarial freedom from stroke at 3 years in CM group was 99.0%. The modification of the maze procedure including cryoablation for pulmonary venous isolation provided less aortic cross-clamp time and less amount of chest tube drainage with the comparable recovery and maintenance of sinus rhythm with KM. CM is a reliable and less invasive surgical option for the AF associated with mitral valve disease.