Clinical Research
Abnormalities of the Left Atrium
Left Atrial Contractile Function Following a Successful Modified Maze Procedure at Surgery and the Risk for Subsequent Thromboembolic Stroke

https://doi.org/10.1016/j.jacc.2011.05.051Get rights and content
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Objectives

The aim of this study was to evaluate whether certain post-Maze left atrial (LA) contractile profiles may pose a risk for ischemic stroke.

Background

The mechanical contraction of the left atrium may be modified after the Maze procedure. Whether this imposes a risk for stroke, even in the presence of sinus rhythm and after removal of the LA appendage, is not known.

Methods

Clinical, surgery-related, and echocardiographic data from 150 patients who underwent radiofrequency and cryoablation Maze procedures without the use of atrial incisions between 2004 and 2009 and were in sustained sinus rhythm were collected and analyzed. The occurrence of stroke was evaluated by reviewing clinical records. All stroke events were adjudicated by a neurologist.

Results

At a mean follow-up time of 24.5 months, 15 patients (10%) had experienced ischemic strokes. Forty-seven patients (31%) had no evidence of LA mechanical contraction at 3 months after surgery (baseline assessment) and on follow-up echocardiography. Multivariate analysis showed that a lack of LA mechanical contraction at baseline was associated with a 5-fold increase in the risk for stroke (p = 0.02) during follow-up. Larger atria imposed a significant risk as well; LA volume index ≥33 ml/m2 was associated with a 3-fold risk increase (p = 0.03). These effects were maintained regardless of the lack of mechanical valve implantation and anticoagulation treatment.

Conclusions

Absence of LA contraction and LA volume index ≥33 ml/m2 result in a significant increase in the risk for thromboembolic stroke after the Maze procedure for patients in sinus rhythm.

Key Words

left atrial function
Maze
stroke

Abbreviations and Acronyms

AF
atrial fibrillation
CI
confidence interval
HR
hazard ratio
LA
left atrial
LAA
left atrial appendage
LAMC
left atrial mechanical contraction
LAVI
left atrial volume index
SR
sinus rhythm

Cited by (0)

Dr. Raanani is a medical consultant for Edwards Lifesciences and Medtronic. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Drs. Buber and Luria contributed equally to this work.