THE CONTRIBUTION OF THE LEFT ATRIOVENTRICULAR PLANE DISPLACEMENT DURING LOW-DOSE DOBUTAMINE STRESS ECHOCARDIOGRAPHY IN PREDICTING RECOVERY OF LEFT-VENTRICULAR DYSSYNERGIES

The aim of this study was to assess the significance of the left systo lic atrioventricular (AV) plane displacement during low dose dobutamin e stress echocardiography (DSE), in predicting the recovery of left ve ntricular dyssynergies after revascularization. In 30 infarctiers with left ventricular dysfunction scheduled for RE (14 percutaneous transl uminal coronary angioplasty and 16 coronary artery bypass graft) and i n 25 age- and sex-matched healthy subjects, a DSE, using a 16 ventricu lar segment model and a four-grade scoring system for the assessment o f regional wall motion of the left ventricle was performed. Prior and during DSE, the left systolic AV plane displacement was recorded from the apical four- and two-chamber views, by M-mode echo, at four left v entricular sites, corresponding to the septal, Lateral, anterior, and inferior walls, both in, patients and controls. The study was repeated in all patients 101 +/- 14 days after successful revascularization, H ealthy subjects showed a significant increase of left systolic AV plan e displacement at all left ventricular sites during dobutamine infusio n. (DI) (P < 0.001). Patients also exhibited a significant maximum inc rease of left systolic AV plane displacement during DSE only in the dy ssynergic sites with functional improvement in. the postrevascularizat ion echocardiogram (P < 0.001). In the remaining dyssynergic sites, wi thout functional improvement after revascularization, the left systoli c AV plane displacement did not change (P > 0.05). Selecting a maximum LAVPD increase of > 2 mm at any site of the left ventricule to predic t recovery of the regional ventricular dyssynergies, results in a sens itivity of 91%, specificity of 83%, positive predictive value of 88%, and negative predictive value of 87%. When two-dimensional DSE was use d for the detection of reversible dysfunction, sensitivity and specifi city were found to be 81.5% and 87.5%, respectively, while the positiv e and negative predictive values were 90% and 78%, respectively. When the two methods were in agreement the sensitivity was 90%, the specifi city 100%, and the positive and negative predictive values were 100% a nd 84.2%, respectively. The assessment of left systolic AV plane displ acement during DI constitutes a new, simple, and accurate method in th e prediction of left ventricular dyssynergy recovery after revasculari zation. The combination of this method and two-dimensional DSE are bas ic predictor markers of viability of dysfunctional myocardium.