Doppler strain imaging closely reflects myocardial energetic status in acute progressive ischemia and indicates energetic recovery after reperfusion.
BACKGROUND
Capitalizing on mechanoenergetic coupling, we investigated whether strain echocardiography can noninvasively estimate the ratio of adenosine triphosphate (ATP) to adenosine diphosphate (ADP), a marker of energetic status during acute myocardial ischemia and reperfusion.


METHODS
Twenty-eight pigs were divided into 7 groups (1 baseline, 4 ischemic, and 2 reperfusion). Ischemia was induced by left anterior descending coronary artery occlusion. Longitudinal systolic lengthening (SL) and postsystolic shortening (PSS) strain were measured by echocardiography. The ATP/ADP ratio was obtained from myocardial biopsies in the ischemic and control regions.


RESULTS
SL and PSS strain and the ATP/ADP ratio progressively decreased (P < .05) with increased duration (12, 40, 120, and 200 minutes) of ischemia. A mathematical formula (ATP/ADP = -0.97 + 0.25 x PSS strain + 0.20 x SL strain) estimated best the ATP/ADP ratio (r = 0.94, P < .05). Reperfusion after 12 but not after 120 minutes of ischemia significantly improved the ATP/ADP ratio and decreased SL and PSS strain.


CONCLUSIONS
Strain echocardiography closely reflected changes and enabled the noninvasive estimation of the ATP/ADP ratio. A higher ATP/ADP ratio is associated with functional improvement after reperfusion.
Korinek
Josef
J
Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
Sengupta
Partho P
PP
Wang
Jianwen
J
Romero-Corral
Abel
A
Boukatina
Anna E
AE
Vitek
Jan
J
Krishnamoorthy
Vijay K
VK
Cha
Stephen S
SS
Dzeja
Petras P
PP
Terzic
Andre
A
Khandheria
Bijoy K
BK
Belohlavek
Marek
M
D000244:Adenosine Diphosphate / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D015150:Echocardiography, Doppler / Q000379:methods*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D015428:Myocardial Reperfusion Injury / Q000000981:diagnostic imaging* / Q000378:metabolism*; D013552:Swine
D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate