Evaluation of Left Ventricular Longitudinal, Radial, and Circumferential Strains in Subjects with Normal Variations of Coronary Dominance: A Preliminary Comparative Study.

BACKGROUND: The aim of this study was to evaluate the contractile function of the left ventricular muscles in subjects with normal coronary artery and normal variations of coronary dominance. METHODS: This study was performed on 90 adult subjects with normal results of coronary arteries angiography, echocardiography, and electrocardiography. The participants were categorized into 3 groups of 30 with right-dominant, left-dominant, and codominant variations. Two-dimensional transthoracic echocardiography was performed with apical 2-, 3-, and 4-chamber views and parasternal basal, mid, and apical short-axis views. Then, images were analyzed offline using the velocity vector imaging method. In all studied groups, the mean and standard deviation of left ventricle coronary territorial longitudinal, circumferential, radial strains, and left ventricle global strains were determined. They were compared in 3 layers of sub-endocardial, myocardium, and sub-epicardial. RESULTS: In terms of longitudinal and circumferential strains, there were significant differences in the most coronary territories and global strain among the right-dominant, left-dominant and codominant groups (P < .05). No significant differences in terms of territorial and global radial strains were observed among the study groups (P > .05). CONCLUSION: Strain level decreased from endocardium to epicardium in all studied groups. Territorial and global contractile functions (longitudinal and circumferential strains) of the left ventricle vary depending on the variations of coronary arteries.

Differentiation of the Left and Right Side Interventricular Septum Function in Healthy Subjects by Vector Velocity Imaging.

BACKGROUND: The present study aimed to assess and compare regional strain of the right and left sides of interventricular septum in healthy subjects using velocity vector imaging analysis due to the importance of interventricular septum and limited basic information about the exact function of the interventricular septum. METHODS: The present study was conducted on 40 healthy subjects. Echocardiography was performed in the apical 4-chamber view in the left lateral decubitus position. Image analysis was done offline with velocity vector imaging; the longitudinal strain and strain rate were calculated during 3 cardiac cycles. Strain-time and strain rate-time curves in basal, middle, and apical segments of the left and right sides of interventricular septum were recorded; peak values and time to peak strain were determined. RESULTS: There was no significant difference between the longitudinal strain in the right and left basal (-17.7 ± 5.10% vs. -18.2 ± 5.14%, P=.550), middle (-17.1 ± 4.53% vs. -17.9 ± 4.29%, P = .197) segments, strain rate of basal (-1.1 ± 0.36 1/s vs. -1.0 ± 0.36 1/s, P = .350), and middle (-1.0 ± 0.30 1/s vs. -1.1 ± 0.32 1/s, P =0.551) segments. However, there was a significant difference between the longitudinal strain (-22.2 ± 5.55% vs. -16.6 ± 4.45%, P < .001) and strain rate (-1.5 ± 0.46 1/s vs. -1.1 ± 0.33 1/s, P < .001) of the apical segment. Time to peak strain was significantly different only in the middle segment of interventricular septum (right side: 351.0 ±11.5 ms vs.left side: 344.4 ± 13.1 ms, P = .004). CONCLUSIONS: The findings of this study suggest that the right and left function of the septum was comparable in the basal and middle segments of healthy subjects; this function was significantly different in the apical segments.

The effects of adeno/tonsillectomy on cardiopulmonary function based on echocardiography indices in children with primary snoring and mild obstructive sleep apnea.

BACKGROUND: The goal of this study was to evaluate the effects of adenotonsillectomy on heart function based on echocardiography indices in children with primary snoring (PS) and mild obstructive sleep apnea due to adenotonsillar hypertrophy (ATH). METHODS: 55 children (aged 7 to 11 years old) with PS and ATH who were a candidate for adenotonsillectomy from August 2018 to June 2019 evaluated. A history of Upper Respiratory Tract Obstruction was obtained, clinical examination was performed and the cases suspicious for moderate to severe degrees of Obstructive Sleep Apnea Syndrome were excluded. Echocardiography was performed one week before and 3-6 months after surgery. All data were analyzed by SPSS version 19 and P-value<0.05 was considered significant. RESULTS: From 55 enrolled cases, 42 [30 boys (71.5%) and 12 girls (28.5%)] completed the study course. Tricuspid Annular Plane Systolic Excursion (TAPSE), Ejection Fraction (EF), Right Ventricular Peak Systolic Myocardial Velocity (RVSM), Right Ventricular Fractional Area Change (RVFAC) were increased significantly and Isovolumic Contraction Time (IVCT) index was decreased significantly after surgery (P-value<0.05). The difference of indices between the two sexes was not significant after surgery (P-value>0.05). CONCLUSION: Adenotonsillectomy can improve cardiac function indices in patients with PS due to ATH especially in terms of right ventricle (RV) function and reduction in pulmonary artery pressure. So, although "subclinical", it is better to be considered PS not just as annoying noise for roommates before significant clinical cardiac problems happen.

Right ventricular dysfunction and associated factors in patients after coronary artery bypass grafting.

BACKGROUND: Coronary artery bypass grafting (CABG) surgery is widely accepted as a revascularization method for coronary artery disease (CAD). Despite survival benefit and improvement in quality of life, CABG may impose major morbidities and significant complications. Right ventricle (RV) dysfunction is an important complication that may affect patient's longevity and functional capacity. The aim of this study was to evaluate the relationship between RV dysfunction and some invisible parameters like inferior vena cava (IVC) size with physical capacity. METHODS: In this prospective study, 61 eligible CABG candidates were enrolled and RV function was assessed by echocardiographic parameters before CABG and one week and six months after the procedure, using tricuspid annular plane systolic excursion (TAPSE), Tei Index (TI), peak systolic movement (Sm) (cm/s), and IVC size. Functional capacity was assessed by six-minute walk test (6-MWT) 6 months after CABG. RESULTS: 58 patients who did not have any perioperative RV dysfunction were remained until the end of study; mean age was 58.2 ± 7.9 years with 68.9% being men, and 3 patients died after CABG. Preoperatively, septal motion, RV indices, and IVC size were normal in all patients. The frequency of RV dysfunction according to abnormal TAPSE index, TI, and peak Sm one week after surgery was 81.0%, 79.0%, and 62.0%, respectively, and 6 months after surgery was 49.0%, 49.0%, and 37.0%, respectively. Mean walked distance in 6-MWT was significantly less in patients with RV dysfunction, older age, and higher number of involved vessels (P < 0.001). CONCLUSION: The significant reduction in RV function and impairment of exercise capacity after CABG in this study suggests cardiologists to pay more attention to RV assessment in follow-up visits of patients undergoing GABG.