Although dobutamine-atropine stress echocardiography (DSE) is an established technique for detecting coronary artery disease (CAD), new echocardiographic parameters have been recently described to influence the prognostic value of this test.
Objective:
To determine the influence of left atrial anatomical evaluation on the prognostic value of DSE in patients with known or suspected CAD.
Methods:
From January 2000 to October 2004 we studied 981 pts (61±12 years, 536 men) who underwent DSE with early-atropine injection protocol. Primary end-point was major cardiovascular events, defined as non-fatal myocardial infarction (MI) and cardiac death (CD). Secondary end-point was major cardiovascular events plus revascularization (surgical and percutaneous). Left atrial diameter was determined by two-dimensional echocardiography in longitudinal paraesternal view and left atrial volume in apical 4-chamber view, at rest. Abnormal DSE was defined as fixed or inducible wall motion abnormalities. Pts were followed for a mean of 18 months (6 to 47 months).
Results:
DSE was abnormal in 330(34%) pts. Mean left atrial diameter was 3.9±0.6 cm (2.2±0.4 cm/m2) while mean left atrial volume was 54.4±18.9 ml (30.7±11.2 ml/m2). Major cardiovascular events occurred in 39(4%) pts (29 CD and 10 non-fatal MI). A total of 120(12%) pts achieved secondary end-point. By univariate analysis the predictors of CD or non-fatal MI were left atrial diameter (p=0.0013), left atrial volume (p<0.001), male sex (p=0.007), diabetes mellitus (p=0.013), previous MI (p=0.013), left ventricular ejection fraction (p<0.001), and abnormal DSE (p<0.001). By multivariate analysis, the independent predictors of CD and MI were left atrial volume (RR=1.02; 95%CI =1.01–1.03; p<0.001) and abnormal DSE (RR=6.38; 95%CI =3.1–13.2; p<0.001). When considering secondary end-point, independent predictors of combined events were left atrial volume (RR=1.01; 95%CI =1.01–1.02; p<0.001), male sex (RR=1.7; 95%CI =1.1–2.5; p=0.017), and abnormal DSE (RR=4.4; 95%CI =2.9 – 6.6; p<0.001).
Conclusion:
Resting left atrial volume is an independent predictor of major cardiovascular events and combined events and can be used as an incremental tool for prognostic evaluation of patients who underwent DSE.
LEFT ATRIAL VOLUME DETERMINED BY CMR IS AN INDEPENDENT PREDICTOR OF INCIDENT ADVERSE CARDIOVASCULAR EVENTS: THE FRAMINGHAM HEART STUDY