title: Doppler strain imaging closely reflects myocardial energetic status in acute progressive ischemia and indicates energetic recovery after reperfusion.
abstract: 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.
authors.affiliation: Division of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.
authors.forename: Josef
authors.initials: J
authors.lastname: Korinek
authors.forename: Partho P
authors.initials: PP
authors.lastname: Sengupta
authors.forename: Jianwen
authors.initials: J
authors.lastname: Wang
authors.forename: Abel
authors.initials: A
authors.lastname: Romero-Corral
authors.forename: Anna E
authors.initials: AE
authors.lastname: Boukatina
authors.forename: Jan
authors.initials: J
authors.lastname: Vitek
authors.forename: Vijay K
authors.initials: VK
authors.lastname: Krishnamoorthy
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Cha
authors.forename: Petras P
authors.initials: PP
authors.lastname: Dzeja
authors.forename: Andre
authors.initials: A
authors.lastname: Terzic
authors.forename: Bijoy K
authors.initials: BK
authors.lastname: Khandheria
authors.forename: Marek
authors.initials: M
authors.lastname: Belohlavek
mesh_terms: 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
chemical_list: D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate