[Value of electrocardiographic treadmill test for rate control strategy in permanent atrial fibrillation].

AIM: of our study was to determine the correlation between physical activity tolerance assesed by exercise tolerance test (ETT) and dynamics of change of echocardiographic parameters of left atrium (LA) and left ventricle (LV) in standard transtoracic echocardiography (TTE) in long-term follow up of patients with persistent nonvalvular atrial fibrillation (AF).

MATERIALS AND

METHODS

We studied 67 patients (W/M: 23/44; mean age 63.2 +/- 7.1 years) with persistent AF lasting longer than 1 month. Rate control strategy targeted resting heart rate 70-90/min. All study subject underwent ETT in order to assess their exercise capacity. Before ETT we performed TTE in all patients and calculated the area of LA (LAar), longitudinal and saggital diameter of LA (LAlax, LAsax), LV end-diastolic diameter (LVEDD) and LV shortening fraction (FS). TTE was performed again in 2 and 12 months after beginning of observation.

RESULTS

Using variation analysis we established the correlation between time of ETT in patients with persistent AF and dynamics of change of specific echocardiographic parameters in 12 months follow-up. In patients with ETT time <60 sec we observed statistically significant rise of LAar from 26.5 +/- 6.1 to 29.6 +/- 4.9 cm2 (p < 0.05; ANOVA) and deterioration of LV function assessed with FS from 35.6 +/- 5.3% on the beginning to 31.7 +/- 7.4% at the end of study (p < 0.02; ANOVA). There was no correlation between time of ETT and dynamics of change of other echocardiographic parameters in patients with time of ETT >60 sec.

CONCLUSIONS

Time of exercise tolerance test limited with heart failure symptoms is an independent factor predicting dynamics of change of chosen echocardiographic parameters of left heart in long-term observation of patients with persistent atrial fibrillation.