Complete Coronary Revascularization Improves Survival in Octogenarians.

BACKGROUND: Completeness of revascularization is important for patients undergoing coronary artery bypass graft surgery, but information on its long-term impact in octogenarian patients is lacking. METHODS: From 1986 to 2004, 525 consecutive patients aged 80 years or more (mean age 82 ± 3 years) underwent coronary artery bypass graft surgery and were followed for a minimum of 10 years or until death. Outcome was stratified based on extent of revascularization, defined as total (graft to every diseased vessel), complete (graft to each region but not every diseased vessel), or incomplete (bypass not done to all suitable regions or vessels). RESULTS: Follow-up of 3,155 patient-years (mean follow-up 73 ± 54 months) was 99% complete. Overall operative mortality was 8% (41 of 525), and was lower for elective than for urgent/emergent cases (4.2% versus 16% ± 6%, p < 0.001, respectively). There was a trend toward higher operative mortality with incomplete (13% ± 6%) versus complete (8% ± 4%) or total revascularization (6% ± 3%; p = 0.09). For operative survivors, mean survival was significantly improved with total and complete revascularization (6.9 and 6.8 years, respectively), compared with incomplete revascularization (5.4 years, p < 0.008). For total, complete, and incomplete revascularization, survival at 5 years was 61% ± 3%, 61% ± 4%, and 47% ± 5%, respectively. Ten-year survival was 27% ± 3%, 21% ± 3%, and 16% ± 4% (p = 0.01), respectively, in these groups. CONCLUSIONS: Incomplete revascularization in octogenarians is associated with decreased long-term survival when compared with total or complete revascularization. There was no survival benefit with total over complete revascularization. Octogenarians can have good long-term survival, especially with adequate revascularization.

Detection of Atrial Fibrillation After Surgical Ablation: Conventional Versus Continuous Monitoring.

BACKGROUND: Current guidelines recommend at least 24-hour Holter monitoring at 6-month intervals to evaluate the recurrence of atrial fibrillation (AF) after surgical ablation. In this prospective multicenter study, conventional intermittent methods of AF monitoring were compared with continuous monitoring using an implantable loop recorder (ILR). METHODS: From August 2011 to January 2014, 47 patients receiving surgical treatment for AF at 2 institutions had an ILR placed at the time of operation. Each atrial tachyarrhythmia (ATA) of 2 minutes or more was saved. Patients transmitted ILR recordings bimonthly or after any symptomatic event. Up to 27 minutes of data was stored before files were overwritten. Patients also underwent electrocardiography (ECG) and 24-hour Holter monitoring at 3, 6, and 12 months. ILR compliance was defined as any transmission between 0 and 3 months, 3 and 6 months, or 6 and 12 months. Freedom from ATAs was calculated and compared. RESULTS: ILR compliance at 12 months was 93% compared with ECG and Holter monitoring compliance of 85% and 76%, respectively. ILR devices reported a total of 20,878 ATAs. Of these, 11% of episodes were available for review and 46% were confirmed as AF. Freedom from ATAs was no different between continuous and intermittent monitoring at 1 year. Symptomatic events accounted for 187 episodes; however, only 10% were confirmed as AF. CONCLUSIONS: ILR was equivalent at detecting ATAs when compared with Holter monitoring or ECG. However, the high rate of false-positive readings and the limited number of events available for review present barriers to broad implementation of this form of monitoring. Very few symptomatic events were AF on review.

Illustrated techniques for performing the Cox-Maze IV procedure through a right mini-thoracotomy.

The Cox-Maze IV procedure has replaced the "cut-and-sew" technique of the original Cox-Maze operation with lines of ablation created using bipolar radiofrequency (RF) and cryothermal energy devices. In select patients, this procedure can be performed through a right mini-thoracotomy. This illustrated review is the first to detail the complete steps of the Cox-Maze IV procedure performed through a right mini-thoracotomy with careful attention paid to operative anatomy and advice. Pre- and post-operative management and outcomes are also discussed. This should be a practical guide for the practicing cardiac surgeon.

Performance of a novel bipolar/monopolar radiofrequency ablation device on the beating heart in an acute porcine model.

OBJECTIVE: Although the advent of ablation technology has simplified and shortened surgery for atrial fibrillation, only bipolar clamps have reliably been able to create transmural lesions on the beating heart. Currently, there are no devices capable of reproducibly creating the long linear lesions in the right and left atria needed to perform a Cox-Maze procedure. This study evaluated the performance of a novel suction-assisted radiofrequency device that uses both bipolar and monopolar energy to create lesions from an epicardial approach on the beating heart. METHODS: Six domestic pigs underwent median sternotomy. A dual bipolar/monopolar radiofrequency ablation device was used to create epicardial linear lesions on the superior and inferior vena cavae, the right and left atrial free walls, and the right and left atrial appendages. The heart was stained with 2,3,5-triphenyl-tetrazolium chloride, and each lesion was cross-sectioned at 5-mm intervals. Lesion depth and transmurality were determined. RESULTS: Transmurality was documented in 94% of all cross sections, and 68% of all ablation lines were transmural along their entire length. Tissue thickness was not different between the transmural and nontransmural cross sections (3.1 ± 1.3 and 3.4 ± 2.1, P = 0.57, respectively), nor was the anatomic location on the heart (P = 0.45 for the distribution). Of the cross sections located at the end of the ablation line, 11% (8/75) were found to be nontransmural, whereas only 4% (8/195) of the cross sections located within the line of ablation were found to be nontransmural (P = 0.04). Logistic regression analysis demonstrated that failure of the device to create transmural lesions was associated with low body temperature (P = 0.006) but not with cardiac output (P = 0.54). CONCLUSIONS: This novel device was able to consistently create transmural epicardial lesions on the beating heart, regardless of anatomic location, cardiac output, or tissue thickness. The performance of this device was improved over most devices previously tested but still falls short of ideal clinical performance. Transmurality was lower at the end of the lesions, highlighting the importance of overlapping lines of ablation in the clinical setting.

Incremental risk of the Cox-maze IV procedure for patients with atrial fibrillation undergoing mitral valve surgery.

OBJECTIVE: More than 50% of atrial fibrillation surgery occurs in the setting of mitral valve surgery. Despite this, no risk models have been validated for concomitant arrhythmia surgery. The purpose of the present study was to quantify the additional risk of performing the Cox-maze IV procedure for patients undergoing mitral valve surgery. METHODS: From January 2002 to June 2011, 213 patients with mitral valve disease and preoperative atrial fibrillation underwent mitral valve surgery only (n = 109) or in conjunction with a Cox-maze IV procedure (n = 104). The operative mortality for the mitral valve procedure alone was predicted for each group using the Society of Thoracic Surgeons perioperative risk calculator. The risk attributed to the added Cox-maze IV procedure was calculated by comparing the predicted mortality rate of an isolated mitral valve procedure and the actual mortality rate of mitral valve surgery with a concomitant Cox-maze IV procedure. RESULTS: For patients not undergoing a Cox-maze IV procedure, the predicted and actual postoperative mortality rate was 5.5% and 4.6% (5 of 109), respectively. For patients receiving mitral valve surgery and a concomitant Cox-maze IV, the predicted and actual postoperative mortality of the mitral valve procedure was 2.5% and 2.9% (3 of 104), respectively, and not significantly different. Patients not offered a Cox-maze IV procedure had significantly more serious comorbidities. CONCLUSIONS: For patients with atrial fibrillation and mitral valve disease undergoing mitral valve surgery, the decision to offer a concomitant Cox-maze IV procedure will be influenced by the underlying comorbid conditions. Nonetheless, in selected lower risk patients, the addition of a Cox-maze IV procedure did not significantly affect the procedural mortality.

Predictors and risk of pacemaker implantation after the Cox-maze IV procedure.

BACKGROUND: The incidence of and causes for permanent pacemaker implantation (PPM) after surgical arrhythmia procedures remain poorly understood because of the varied lesion patterns and energy sources reported in small series. This study characterized the incidence, indications, and risk factors for PPM after the Cox-maze IV (CMIV) procedure when performed as either a lone or a concomitant procedure. METHODS: A retrospective analysis of 340 patients undergoing a CMIV as either a lone (n = 112) or a concomitant (n = 228) procedure was conducted. The incidence, indication, and variables associated with PPM implantation within 1 year of the operation were assessed. Follow-up was conducted at 30 days and 1 year and was 90% complete. RESULTS: The incidence of PPM after a lone CMIV procedure was 5%. Patients with concomitant cardiac operations had a nonsignificant increase in PPM insertion at 30 days (11% vs 5%, p = 0.14) and 1 year (15% vs 6%, p = 0.06) when compared with lone CMIV patients. Of patients who required pacemakers, sinus node dysfunction was present in 79% (35/44) of patients in the entire series and in 88% (8/9) after lone CMIV. After PPM, 84% (37/44) of patients remained paced at last follow-up. Multivariate analysis identified age (odds ratio = 1.10 [1.06-1.14], p < 0.001) as the only variable associated with higher risk of a PPM after any CMIV procedure. CONCLUSIONS: The risk of PPM implantation after a lone CMIV is 5% and increases with age. The need for a PPM after a CMIV is largely due to SA node dysfunction, which appears unlikely to recover. These data should help physicians counsel patients regarding the perioperative risks associated with the CMIV.

Surgical treatment of atrial fibrillation.

Atrial fibrillation (AF) is the most common cardiac arrhythmia, resulting in significant morbidity and mortality, and enormous socio-economic consequences. Though many surgical procedures exist for the treatment ofAF, the Cox-Maze IV procedure developed at Washington University has shown excellent long-term results in diverse patient populations. Furthermore, advances in preoperative diagnostic technology currently under investigation at our institution may allow for further refinement and individualization of the surgical treatment ofAF in the future.

Cox-Maze IV results for patients with lone atrial fibrillation versus concomitant mitral disease.

BACKGROUND: This study compared Cox-Maze IV (CMIV) outcomes for the treatment of atrial fibrillation (AF) in patients with lone AF vs those with AF and mitral valve (MV) disease. METHODS: Since 2002, 200 patients have undergone a CMIV procedure for lone AF (n=101) or concomitantly with MV operations (n=99). Preoperative, perioperative, and late outcomes between these groups were compared. Data were collected prospectively and reported at 3, 6, and 12 months. RESULTS: Lone AF patients had AF of longer duration; patients with AF and MV disease were older, with larger left atria and worse New York Heart Association classification (p<0.05). Operative mortality (1% vs 4%, p>0.05, respectively) was similar between both groups. Perioperative atrial tachyarrhythmias were more prevalent in patients with concomitant MV operations (57% vs 41%, p=0.03); however, freedom from AF and antiarrhythmics was similar for both groups at 12 months (76% and 77%). The only predictor for atrial tachyarrhythmia recurrence or arrhythmic drug dependence was failure to isolate the posterior left atrium (p<0.01). CONCLUSIONS: Patients with AF and MV disease have distinct comorbidities compared with patients with lone AF. However, the CMIV is safe and effective in both groups and should be considered for patients with AF undergoing MV operations. Patients with MV disease had more atrial tachyarrhythmias at 3 months, but freedom from AF and antiarrhythmics was similar to patients with lone AF at 1 year. The posterior left atrium should be isolated in every patient, because this was the only predictor for failure of the CMIV for either group.