Long axis strain by MRI and echocardiography in a postmyocardial infarct population.
OBJECTIVE
To compare long axis strain (LAS) by magnetic resonance imaging (MRI) and echocardiography in a postinfarct patient population. Long axis left ventricle (LV) function is a sensitive index of incipient heart failure by echocardiography, but is less well established in MRI. LAS is an index of global LV function, which is easily assessed in cine loops provided by most cardiac MRI protocols.


METHODS
In all, 116 patients (57 ± 9 years) were studied the same day using echocardiography and MRI 7.4 ± 4.1 months after a first myocardial infarction. LV length was measured in end diastole and end systole in conventional cine images with a temporal resolution of 50 msec or less, and LAS (%) was calculated as the change in LV length, relative to end diastole. Infarct mass was assessed by contrast-enhanced MRI.


RESULTS
LAS was progressively reduced in patients with larger infarcts, and demonstrated good correlations with infarct mass (r = 0.55, P < 0.01). There was a good agreement between LAS assessed by echocardiography and MRI (r = 0.77, P < 0.01), and between LAS by MRI and speckle tracking strain by echocardiography (r = 0.74, P < 0.01).


CONCLUSIONS
LAS is an index that allows measurement of LV long axis function by conventional cine MRI.
Department of Cardiology, Johns Hopkins University, Baltimore, Maryland, USA; Department of Cardiology, University of Oslo and Oslo University Hospital, Oslo, Norway.
Ola
O
Gjesdal
André L C
AL
Almeida
Einar
E
Hopp
Jan Otto
JO
Beitnes
Ketil
K
Lunde
Hans-Jørgen
HJ
Smith
Joáo A C
JA
Lima
Thor
T
Edvardsen
D000368:Aged; D000465:Algorithms; D003971:Diastole / Q000502:physiology; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology* / Q000628:therapy; D062645:Percutaneous Coronary Intervention; D013314:Stress, Mechanical; D013599:Systole / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000503:physiopathology*
echocardiography; heart; long axis; strain; validation