Widimsky P, Tousek P, Rokyta R, et al.Charles University Prague, CZ

PRAGUE-7 Study

(Hot Lines presenter)

Background.

• Surgical atrial ablation procedure (MAZE) may restore sinus rhythm (SR) in pts with atrial fibrillation (AF) undergoing cardiac surgery.

• Hypothesis (formulated by cardiac surgeons):

(1)MAZE restores SR after surgery (2)without increasing perioperative

complications(3)SR presence may improve long term

outcomes.

Methods

• Prospective randomized open multicenter study

• Primary efficacy outcome: SR presence (without any AF episode) during 24-hours ECG after 1 year.

• Primary safety outcome at 30 days: death / myocardial infarction / stroke / renal failure.

• Main secondary outcome: composite of death, major bleeding, stroke or hospitalization for heart failure after 1 and 5 years.

PatientsInclusion criteria:•Heart team indication for cardiac surgery•AF documented at least twice in last six months - paroxysmal or (long standing) persistent•signed informed consent•age over 18 years.

Exclusion criteria:•Emergent surgery

224 pts with AF scheduled for valvular and/or coronary surgery•MAZE group (left atrial surgical ablation, n=117)•Non-MAZE group (no ablation, n=107)

Baseline characteristic n (%) MAZE (n = 117) Non-MAZE (n = 107)

Age (years) 69.9 ± 7.8 71.0 ± 7.9

Paroxysmal AF 26 (22.2) 33 (30.8)

Persistent AF 30 (25.6) 25 (23.4)

Longstanding persistent AF 61 (52.1) 49 (45.8)

Atrial fibrillation just prior surgery 91 (77.8) 70 (65.4)

Left atrial diameter (mm) 48.7 ± 7.3 47.7 ± 7.1

Mean NYHA functional class 2.3 ± 0.6 2.3 ± 0.7

Prior stroke / TIA 13 (11.1) 15 (14.0)

Diabetes 41 (35.0) 40 (37.4)

Prior major bleeding 4 (3.4) 6 (5.6)

Ejection fraction (%) 52.6 ± 10.9 49.9 ± 12.5

Logistic EuroSCORE 5.8 (3.2-9.9) 6.8 (4.0-11.6)

Surgical procedure• Cryomaze (ATS) in 97% pts ,

radiofrequency in 3% pts.

• Ablation time for each lesion 90 seconds.

• Lesion set: pulmonary veins ablation, left atrial appendage exclusion and three interconnecting lesions

• Epicardially or endocardially (based on whether LA is opened during the main surgical procedure)

Procedure types (all-comers with AF)

Sinus rhythm after 1 year (primary efficacy end-point, Holter 24-hour ECG)

p = 0,002

p = 1.000

p = 0,194

p< 0,001

Evolution of sinus rhytm during 1 year(12-lead ECGs)

Perioperative complicationsPrimary safety outcome (death / myocardial infarction /

stroke / renal failure at 30 days)

p = 0,411

Long-term adverse events(Death/ major bleeding/ stroke/ hospitalization for heart

failure after 1 year)

05

1015202530354045

MAZE

Non-MAZE

p = 0,785

p = 0,800

p = 0,654

p = 0,319

p = 0,680

Secondary outcomes at 1 year

p=0,825p=0,887

p=0,174

Conclusions

(1) Surgical ablation improves the likelihood of SR presence up to 1 year postoperatively

(2) Without perioperative complications

(3) No impact on 1-year clinical outcomes

Most significant rhythm benefit in pts with longstanding persistent AF (no benefit seen in paroxysmal AF).