Evolution of right ventricular function post-acute ST elevation myocardial infarction.
OBJECTIVE
To characterize the evolution of right ventricular (RV) function post-myocardial infarction (MI), to describe the culprit vessel involved with RV injury and to assess the concordance between RV injury on magnetic resonance imaging (MRI) and RV infarct on electrocardiogram (EKG).


METHODS
Thirty-one patients underwent cardiovascular magnetic resonance (CMR) examinations at three time frames post-ST elevation MI (STEMI).


RESULTS
Of those with an initial normal scan, RV function did not significantly change over time (60.6 ± 6.3, 57.8 ± 6.0, 55.4 ± 5.7, P > 0.05). However, in those whose RVEF (RV ejection fraction) was initially low, it significantly increased from the first scan to the third scan (46.2 ± 3.6, 50 ± 6.6, 51.3 ± 5.2, P < 0.01). Post-hoc testing revealed a significant difference between the 48-hour and the 6-month scan, and between the 48-hour and the 3-week scan; however, there was no significant difference between the 3-week and 6-month scans. Interestingly, 23% of patients with low RVEF at baseline had the left anterior descending (LAD) as the culprit vessel. Only 15% of the low RVEF at baseline group were classified as having an RVMI by EKG criteria.


CONCLUSIONS
The optimal timepoint to assess for RV injury via CMR may be 3 weeks post-acute MI. Standard EKG criteria may underestimate RV injury when compared to CMR.
Schulich Heart Centre, Sunnybrook Research Institute, Sunnybrook Health Science Centre, University of Toronto, Toronto, ON, Canada.
Idan
I
Roifman
Mohammad I
MI
Zia
Anna
A
Zavodni
Rafael
R
Wolff
Nilesh R
NR
Ghugre
Alexander W
AW
Leber
Alexander J
AJ
Dick
Graham A
GA
Wright
Kim A
KA
Connelly
D003287:Contrast Media; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology* / Q000628:therapy*; D009942:Organometallic Compounds; D062645:Percutaneous Coronary Intervention / Q000379:methods; D011379:Prognosis; D011446:Prospective Studies; D018497:Ventricular Dysfunction, Right / Q000503:physiopathology*
D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol
acute myocardial infarction; cardiac magnetic resonance; right ventricle