BACKGROUND: Evaluating outcomes of concurrent Cox-Maze procedures in elderly patients undergoing high-risk cardiac surgery.
METHODS: We retrospectively identified patients aged over 70 years with Atrial Fibrillation (AF) from 2011 to 2017 who had two or more other cardiac procedures. They were subdivided into two groups: 1. Cox-Maze IV AF ablation. 2. No-Surgical AF treatment. A propensity match score was used to generate a homogeneous cohort and to eliminate confounding variables. Heart rhythm was assessed from Holter reports or 12-lead ECG. Follow-up data was collected through telephone consultations and medical records.
RESULTS: There were 239 patients. Median follow up was 61 months. 70 patients had Cox-Maze IV procedures (29.3%). Demographic, intra- and post-operative outcomes were similar between groups although duration of pre-operative AF was shorter in Cox-Maze group (p = 0.001). There was no significant 30-day mortality difference in propensity matched cohorts (n = 84. P = 0.078). Sinus rhythm at annual and latest follow-up was 84.9% and 80.0% respectively in Maze group - 160 patients (66.9%) were alive at long-term follow-up with good survival outcomes in Cox Maze group. There was a high proportion of patients in NYHA 1 status in Cox-Maze group. No differences observed in freedom from stroke (p = 0.80) or permanent pacemaker (p = 0.33) between the groups.
CONCLUSIONS: Surgical ablation is beneficial in elderly patients undergoing high-risk surgery - promoting excellent long-term freedom from AF and symptomatic / prognostic benefits, without added risk. Therefore, surgical risk should not be reason to deny benefits of concomitant AF-ablation.
BACKGROUND: Not required.

Dapagliflozin has been widely used for the treatment of type 2 diabetes mellitus (T2DM) and heart failure (HF). However, data concerning the association between dapagliflozin and the recurrence of atrial fibrillation (AF), especially in patients following Cox-Maze IV (CMIV), are rare. We aim to explore the effect of dapagliflozin on the recurrence of AF after CMIV with and without T2DM or HF.
The study of dapagliflozin evaluation in AF patients followed by CMIV (DETAIL-CMIV) is a prospective, double-blind, randomized, placebo-controlled trial. A total of 240 AF patients who have received the CMIV procedure will be randomized into the dapagliflozin group (10 mg/day, n = 120) and the placebo group (10 mg/day, n = 120) and treated for 3 months. The primary endpoint is any documented atrial tachyarrhythmia (AF, atrial flutter or atrial tachycardia) lasting 30 s following a blanking period of 3 months after CMIV.
DETAIL-CMIV will determine whether the sodium-glucose cotransporter-2 inhibitor dapagliflozin, added to guideline-recommended post-operative AF therapies, safely reduces the recurrence rate of AF in patients with and without T2DM or HF.

UNASSIGNED: The objective of this study was to observe the safety and efficacy of electrophysiological mapping following the Cox-Maze IV procedure and to investigate whether a correlation exists between recurrence of atrial fibrillation (AF) with the completeness of bidirectional electrical isolation and the inducibility of AF immediately after the Cox-Maze IV procedure.
UNASSIGNED: Totally, 80 consecutive patients who suffered from aortic valve or mitral valve disease and persistent AF were randomly enrolled into the control group and electrophysiological mapping following the Cox-Maze IV group (Electrophysio-Maze group). In the Electrophysio-Maze group, patients underwent concomitant Cox-Maze procedure and following electrophysiological mapping of ablation lines in mitral isthmus, left atrial \"box,\" and tricuspid annulus. If the bidirectional electrical isolation of tricuspid annulus ablation line is incomplete, whether to implement supplementary ablation will be independently decided by the operator. Before and after the Cox-Maze IV procedure, AF induction was performed. All patients in both groups were continuously followed-up and underwent electrocardiogram Holter monitoring after 6 months.
UNASSIGNED: In total, 42 Electrophysio-Maze patients and 38 controls were enrolled. Compared with patients in the control group, there were shorter hospital stay, better cardiac remodeling changes, and higher relief from AF during the follow-up period of 6 months in the Electrophysio-Maze group. Within the Electrophysio-Maze group, the rate of incomplete the bidirectional electrical isolation of \"box\" ablation lines was zero, and the rate of incomplete bidirectional electrical isolation of mitral isthmus ablation line or tricuspid annulus ablation line was 23.8%. After two cases of successful complementary ablation on the tricuspid annulus ablation line, the final incomplete bidirectional electrical isolation of annulus ablation lines was 19.0%. There were correlations between late AF recurrence after 6 months with incomplete bidirectional electrical isolation of annulus ablation lines and AF induction immediately after the Cox-Maze IV procedure.
UNASSIGNED: Electrophysiological mapping following the Cox-Maze procedure is safe and effective. Electrophysiological mapping in the Cox-Maze procedure can find out the non-transmural annulus ablation lines by assessing the completeness of bidirectional electrical isolation of ablation lines, guide supplementary ablation, and predict AF recurrence after 6 months.

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, and results in significant morbidity and mortality. The Cox-Maze IV procedure (CMP-IV) has been shown to have excellent efficacy in returning patients to sinus rhythm, but there have been few reports of late follow-up in sizable cohorts of patients with longstanding persistent AF, the most difficult type of AF to treat.
Between May 2003 and March 2020, 174 consecutive patients underwent a stand-alone CMP-IV for longstanding persistent AF. Rhythm outcome was assessed postoperatively for up to 10 years, primarily via prolonged monitoring (Holter monitor, pacemaker interrogation, or implantable loop recorder). Fine-Gray regression was used to investigate factors associated with atrial tachyarrhythmia (ATA) recurrence, with death as a competing risk. Median duration of preoperative AF was 7.8 years (interquartile range: 4.0-12.0 years), with 71% (124/174) having failed at least one prior catheter-based ablation. There were no 30-day mortalities. Freedom from ATAs was 94% (120/128), 83% (53/64), and 88% (35/40) at 1, 5, and 7 years, respectively. On regression analysis, preoperative AF duration and early postoperative ATAs were associated with late ATAs recurrence.
Despite the majority of patients having a long-duration of preoperative AF and having failed at least one catheter-based ablation, the stand-alone CMP-IV had excellent late efficacy in patients with longstanding persistent AF, with low morbidity and no mortality. We recommend consideration of stand-alone CMP-IV for patients with longstanding persistent AF who have failed or are poor candidates for catheter ablation.

BACKGROUND: The Cox-Maze IV procedure is a proven surgical treatment for atrial fibrillation (AF). Previous studies on the procedure and its effect on left atrial mechanical function have yielded mixed results.
METHODS: Sixty-four (64) patients underwent Cox-Maze IV at St Vincent\'s Hospital, Melbourne between March 2010 and May 2016. Baseline characteristics were collected and outcomes assessed including rhythm analysis. Preoperative and postoperative transthoracic echocardiograms were reviewed.
RESULTS: Fifty-seven (57) patients had complete follow-up with all clinical measures collected. The mean age was 71.1±10.2years, 63% being male. Fifty-eight per cent (58%) (33/57) of patients were in AF and 42% (24/57) in sinus rhythm (SR) at preoperative transthoracic echocardiography. Follow-up postoperative transthoracic echocardiography was performed at a mean of 2.3±1.9years. Nineteen (19) patients with a history of paroxysmal AF were in SR both preoperatively and postoperatively. In these patients, there was a significant decrease in Mitral A wave 0.63±0.28m/s (pre-op) vs 0.47±0.29m/s (post-op), p=0.044. There was a significant decrease in left ventricular ejection fraction (LVEF) postoperatively 64.2±9.7% vs 55.0±12.9%, p=0.005. At follow-up, 28% (16/57) were in AF, 61% (35/57) in SR, and 11% (6/57) in a paced rhythm. In a multivariate analysis, predictors of AF recurrence included higher LA volumes (p=0.042) and younger age at surgery p=0.030. Preoperative AF, sex and LVEF had no impact on AF recurrence.
CONCLUSIONS: The Cox-Maze IV procedure, while effective in converting patients to sinus rhythm, may reduce left atrial mechanical function in patients with paroxysmal AF.

Atrial fibrillation (AF) is associated with an increased mortality risk. The Cox-maze IV procedure (CM4) performed concomitantly with other cardiac procedures has been shown to be effective for restoring sinus rhythm. However, few data have been published on the late survival of patients undergoing a concomitant CM4.
Patients undergoing cardiac surgery were retrospectively reviewed from 2001 to 2016 (n = 10,859). Patients were stratified into 3 groups: patients with a history of AF receiving a concomitant CM4 (CM4; n = 438), patients with a history of AF unaddressed during surgery (Untreated AF; n = 1510), and patients without AF history (No AF; n = 8911). Propensity score matching was conducted between the CM4 and Untreated AF groups, and between the CM4 and No AF groups.
Thirty-day mortality was similar between the matched groups. Kaplan-Meier analysis showed greater survival for CM4 compared to Untreated AF (P = .004). Ten-year survival was 62% for CM4 and 42% for Untreated AF. Adjusted hazard ratio was 0.47 (95% confidence interval, 0.26-0.86, P = .014). No difference in survival was found between CM4 and No AF groups with the Kaplan-Meier analysis (P = .847). Ten-year survival was 63% for CM4 and 55% for No AF. Adjusted hazard ratio was 1.03 (95% confidence interval, 0.51-2.11, P = .929).
For selected patients with a history of AF undergoing cardiac surgery, concomitant CM4 did not add significantly to postoperative morbidity or mortality and was associated with improved late survival compared with patients with untreated AF and a similar survival to patients without a history of AF.

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.

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.