Remote Ischemic Conditioning in Patients With Myocardial Infarction Treated With Primary Angioplasty: Impact on Left Ventricular Function Assessed by Comprehensive Echocardiography and Gated Single-Photon Emission CT.
BACKGROUND
we have found that remote ischemic conditioning (rIC), adjunctive to primary angioplasty, increases myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI) and extensive myocardial area at risk (AAR). The present substudy aimed to evaluate the short-term effects of rIC on left ventricular (LV) function.


RESULTS
patients with a first STEMI were randomized to rIC (4 cycles of 5 minutes upper-limb ischemia) during transfer to primary percutaneous coronary intervention (pPCI) (n=123) versus pPCI alone (n=119). Ejection fraction (EF), LV volumes, (2D and 3D echocardiography and myocardial perfusion imaging), and speckle-tracking global longitudinal strain were compared between treatment groups. There was no significant difference in LV function at day 1 (EF-2D, 0.51±0.10 versus 0.49±0.10; P=0.22) and after 30 days (EF-2D, 0.54±0.08 versus 0.53±0.10) between the rIC and the pPCI-alone groups. In patients with extensive AAR ≥35% of LV (n=53), EF after 30 days was higher after rIC than after pPCI alone (EF-2D, 0.51±0.07 versus 0.46±0.09; P=0.05). In patients with anterior infarction (n=97), rIC preserved LV function on day 1 (EF-2D, 0.51±0.11 versus 0.46±0.11; P=0.03) and persistently after 30 days (EF-2D, 0.55±0.08 versus 0.50±0.11; P=0.04; EF-myocardial perfusion imaging, 0.55±0.10 versus 0.49±0.12; P=0.02). These patients had similar AAR, whereas rIC reduced infarct size from 16% to 7% of LV (P=0.01).


CONCLUSIONS
although no significant overall effect was observed, rIC seemed to result in modest improvement in LV function in high-risk patients prone to develop large myocardial infarcts. These results need to be confirmed in larger trials.
Munk
Kim
K
Department of Cardiology, Aarhus University Hospital Skejby, DK-8200 Aarhus N, Denmark. kim.munk@ki.au.dk
Andersen
Niels Holmark
NH
Schmidt
Michael Rahbek
MR
Nielsen
Soren Steen
SS
Terkelsen
Christian Juhl
CJ
Sloth
Erik
E
Bøtker
Hans Erik
HE
Nielsen
Torsten Toftegaard
TT
Poulsen
Steen Hvitfeldt
SH
D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D015331:Cohort Studies; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000628:therapy*; D055414:Myocardial Perfusion Imaging / Q000379:methods; D015428:Myocardial Reperfusion Injury / Q000175:diagnosis / Q000209:etiology; D015588:Observer Variation; D015203:Reproducibility of Results; D012307:Risk Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000209:etiology*; D020257:Ventricular Remodeling