Background: Myocardial deformation imaging allows quantifying myocardial function far beyond what can be done with sole visual assessment. The aim of the present study is to determine whether post-ischemic impairment of regional LV function occuring after exercise could be detected by quantifying territorial longitudinal strain/strain rate changes in patients with coronary artery disease (CAD).
Methods: Eighty nine consecutive patients with suspected CAD underwent stress echocardiography. Peak systolic strain was measured at rest, peak stress and 5 and 10 min after stress. Bull`s eye of strain and strain rate maps were done and compared with coronary angiography results.
Results: There is a significant increase in Peak Systolic strain during exercise and 5 min post exercise with patients without CAD (p<0.001). In patients with CAD there is no significant change in PSS values at rest, peak stress and 5 and 10 min after exercise (p=0.9). Post systolic shortening index (PSI) is significantly higher at rest in patients with CAD ( P-0.001). There is no significant change in PSI index during or after exercise in patients with CAD, however in patients with no CAD PSI increases with exercise (p-0.014). Peak exercise PSS (AUC 0.745) and rest, peak exercise and 5min post exercise PSI (AUC 0.77, 0.74 and 0.72m respectively) had the best accuracy foe detecting CAD at rest, stress and 5 and 10 min post exercise.
Conclusions: Regional myocardial dysfunction that probably developed during rest and exercise can be detected by the strain method in patients with stable effort angina and CAD. We observed that the various indexes change differently during and after exercise and this is altered when CAD is present. PSS at peak stress and PSI index at rest, peak stress and 5 min post stress are the best parameters for detecting CAD at rest and exercise.
