PRAGUE-12: Randomized open multicenter study comparing cardiac surgery with MAZE versus cardiac surgery without MAZE in patients with coronary and/or valvular heart disease and with atrial fi

List of Authors: Petr Widimský1 (presenter), Petr Budera1 (corresponding author), Pavel Osmančík1, Tomáš Vaněk1, Štěpán Jelínek1, Jan Hlavička1, Richard Fojt1, Pavel Červinka2, Michal Hulman3, Michal Šmíd4, Marek Malý5, Zbyněk Straka1
1Cardiocenter, Third Faculty of Medicine, Charles University Prague, Czech Republic, 2Cardiology Department, Masaryk Hospital, Usti nad Labem, Czech Republic, 3National Institute of Cardiovascular Diseases, Bratislava, Slovakia, 4Cardiocenter, Faculty of Medicine Pilsen, Czech Republic, 5National Institute of Public Health, Prague, Czech Republic.

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.

Open multicenter randomized prospective study. Primary efficacy outcome: presence of sinus rhythm (without any AF episode) during 24-hours ECG monitoring 1 year after surgery. Primary safety outcome: combined end point death / myocardial infarction / stroke or transient ischemic attack (TIA) / new onset renal failure requesting hemodialysis at 30 days. Long-term outcome: combined end point death / major bleeding / stroke or TIA / rehospitalization for heart failure at 1 and 5 years. Secondary outcomes: use of anticoagulation at 1 year, use of antiarhythmis drugs at 1 year, pacemaker or cardioverter implantation, catheter ablation, operative data. The study was registered at under the Identifier NCT00665587.

Inclusion criteria: heart team indication for cardiac surgery (coronary bypass and / or valve replacement or repair), atrial fibrillation (paroxysmal, persistent or longstanding persistent) documented at least twice during the last 6 month before the operation, signed informed consent, age >18 years. Exclusion Criterion: emergency surgery. A total of 224 patients in three cardiac surgery centers were randomized by the envelope method into two groups: group A (cardiac surgery with the left atrial ablation procedure) included 117 patients, group B (cardiac surgery without the ablation procedure) included 107 patients. 

The ablation procedure prolonged the total surgical time by 20 minutes (220 min. in group A vs. 200 min. B). A Holter-ECG after one year revealed SR in 60.2% of group A patients vs. 35.5% in group B (p = 0.002). The combined safety end point at 30 days occurred in 10.3% (A) vs.14.7% (B, p = 0.411). There was neither change in the left ventricular ejection fraction nor in the left atrial diameter. Additional results are in table 2:

Table 2. One year results              
(with ablation)

(n = 111)
(without ablation)

(n = 92)
Death   18 (16.2%)      16 (17.4%)      0.800
Bleeding  11 (9.9%)      9 (9.8%)      0.654
Stroke  3 (2.7%)      4 (4.3%)      0.319
Heart failure  26 (23.4%)      24 (26.1%)      0.680
Combined      45 (40.5%)      37 (40.2%)      0.785
NYHA decrease at one
year (mean ± SD)
 0.76 ± 0.9      0.58 ± 0.85      0.174
% of patients with preop.
paroxysmal AF,
and SR at 1-year Holter ECG
 61.9%      58.3%      1.000
% of patients with preop.
persistent AF,
and SR at 1-year Holter ECG
 72%      50%      0.194
% of patients with preop.
longstanding persistent AF,
and SR at 1-year Holter ECG
 53.2%      13.9%      < 0.001

This multicenter randomized study confirmed, that the left atrial ablation procedure performed during cardiac surgery improves the likelihood of sinus rhythm presence one year postoperatively without increasing perioperative complications. However, the higher prevalence of SR did not translate to improved clinical outcomes at one year. Further follow-ups (e.g. 5 year) are warranted to show any potential clinical benefit which might occur later.