Right Ventricular Involvement in either Anterior or Inferior Myocardial Infarction

Background: Unlike left ventricular function, less attention has been paid to Right Ventricular (RV) function after Myocardial Infarction (MI).

Objectives: The current study aimed to compare RV function in patients with inferior and anterior MI.

Patients and Methods: During the study period, 60 patients consecutively presented to the Emergency Department with chest pain were divided into two groups based on their electrocardiographic findings. Accordingly, 25 patients had inferior MI (IMI group) and 35 ones had anterior MI (AMI group). Echocardiography was performed 48 hours after starting the standard therapy. Conventional echocardiographic parameters and Tissue Doppler Imaging (TDI) measurements were acquired from the standard views. Student t-test and the chi-square test were respectively used for comparisons of the normally distributed continuous and categorical variables in the two groups. Besides, P < 0.05 was considered to be statistically significant.

Results: The ratio of early diastolic velocity of the tricuspid flow to early diastolic velocity of the tricuspid annulus in the lateral side (E/E') was significantly higher in the AMI group compared to the IMI group (6.73 ± 1.64 vs. 5.68 ± 1.32, P = 0.01). In addition, abnormal E/E' ratio of the tricuspid valve was present in 27 (77%) and 14 (56%) patients in the anterior and inferior MI groups, respectively. Besides, the RV Tei index was significantly higher in the AMI group compared to the IMI group (0.65 ± 0.11 vs. 0.58 ± 0.13, P = 0.02). Overall, 28 patients (80%) with anterior infarction and 12 patients (48%) with inferior infarction had abnormal RV Tei index. However, no significant difference was found between the two groups regarding other variables.

Conclusions: RV dysfunction commonly occurs after a first acute ST-elevation MI. However, RV functional changes are more pronounced in patients with anterior MI.