Document Type : Original Article

Authors

1 Heart Center, Department of Medical Sciences, Tehran University of Medical Sciences, Tehran, IR Iran.

2 Department of Internal Medical Sciences, Qom University of Medical Sciences, Qom, IR Iran.

3 Student Research Committee, School of Medicine, Qom University of Medical Sciences, Qom, IR Iran.

4 Open Heart Intensive Care Unit, Cardiology Department, Tehran University of Medical Sciences, Tehran, IR Iran.

5 Heart Research Center, Tehran University of Medical Sciences, Tehran, IR Iran.

6 Department of Family and Community Medicine, School of Medicine, Qom University of Medical Sciences, Qom, IR Iran.

Abstract

Background: Data indicate the predictive role of abnormal right ventricular (RV) strain values in postoperative outcomes after coronary artery bypass grafting (CABG). Hence, we aimed to investigate the impact of RV strain assessment by 2D speckle-tracking echocardiography in predicting post-CABG complications.
 
Methods: This study analyzed 149 consecutive low-risk patients with preserved left ventricular (LV) and normal RV function concerning echo parameters, including LV ejection fraction and right ventricular free wall longitudinal strain (RVFWLS), undergoing isolated CABG. RVFWLS was assessed with 2D speckle-tracking echocardiography before surgery. Abnormal RVFWLS was defined as absolute RVFWLS < 19%. The adjusted effects of absolute RVFWLS strain and abnormal RVFWLS on the risk of ICU complications were assessed.
 
Results: Of 149 patients, 90 (60.4%) had abnormal preoperative RVFWLS (−16.5 ± 1.98). There were no significant associations between abnormal RVFWLS and postoperative serum creatinine rise, atrial fibrillation, ventilation time, inotrope use, cumulative dose, on-pump CABG, cardiopulmonary bypass duration, and length of ICU stay (all Ps > 0.05). Postoperative ICU complications were not correlated with absolute RV strain values, except for ventilation time, which had a statistically significant but clinically negligible association with absolute RV strain values (regression coefficient = 1.035; P = 0.016). Since ventilation time is short (< 2 min), despite the positive statistical correlation, it had no clinical value.
 
Conclusions: RV strain measurements by 2D speckle-tracking echocardiography added no benefits to the prediction of ICU complications in low-risk patients undergoing CABG who had preserved or mildly impaired systolic LV function. (Iranian Heart Journal 2024; 25(1): 82-92)

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