Left ventricular mechanics in isolated mild mitral stenosis: a three dimensional speckle tracking study

Advanced Echocardiography Techniques: The Future Stethoscope of Systemic Diseases

Cardiovascular disease (CVD) has been showing patterns of extensive rise in prevalence in the contemporary era, affecting the quality of life of millions of people and leading the causes of death worldwide. It has been a provocative challenge for modern medicine to diagnose CVD in its crib, owing to its etiological factors being attributed to a large array of systemic diseases, as well as its non-binary hideous nature that gradually leads to functional disability. Novel echocardiography techniques have enabled the cardiac ultrasound to provide a comprehensive analysis of the heart in an objective, feasible, time- and cost-effective manner. Speckle tracking echocardiography, contrast echocardiography, and 3D echocardiography have shown the highest potential for widespread use. The uses of novel modalities have been elaborately demonstrated in this study as a proof of concept that echocardiography has a place in routine general practice with supportive evidence being as recent as its role in the concurrent COVID-19 pandemic. Despite such evidence, many uses remain off-label and unexploited in practice. Generalization of echocardiography at the point of care can become a much-needed turning point in the clinical approach to case management. To actualize such aspirations, we recommend further prospective and interventional studies to examine the effect of implementing advanced techniques at the point of care on the decision-making process and evaluate their effectiveness in prevention of cardiovascular morbidities and mortalities.

Evaluation of left and right ventricular functions with three-dimensional speckle tracking in patients with mitral stenosis

BACKGROUND

The function of both ventricles has been suggested to be affected in patients with mitral stenosis. In this study, it was aimed to investigate deformation properties of right (RV) and left ventricle (LV) in rheumatic mitral stenosis (MS) patients with three-dimensional speckle tracking echocardiography (3D-STE).

METHODS

A total of 60 patients were included in the study (20 patients with mild MS diagnosis, 20 patients with moderate MS diagnosis, and 20 healthy volunteers). Three-dimensional echocardiography datasets were obtained for both ventricles in all patients. LV global longitudinal strain (GLS), LV torsion, RV free wall (FW) LS, and interventricular septal (IVS) LS measurements were analyzed.

RESULTS

The LV ejection fraction (EF), RV fractional area change, peak systolic velocity of the tricuspit annulus, isovolumic acceleration, and tricuspid annular plane systolic excursion values were statistically similar and in the normal range. The LV GLS measurements were significantly different among the groups by being highest in the control group and least in the moderate stenosis group. Patients with MS showed higher torsional values, correlated with MS severity. IVS LS, RVFW LS values obtained by RV analysis also differed significantly among groups. The RVFW-GLS values only showed significant difference between the control group and moderate MS group.

CONCLUSION

Patients with MS showed lower LV-GLS and higher LV torsion values. RV deformation indices showed significant decrease in correlation with the severity of the mitral stenosis. In conclusion, our data suggest that subclinical LV and RV systolic dysfunction is present in mild-moderate MS patients and this dysfunction can be detected by 3D-STE.

Early myocardial changes in patients undergoing rheumatic mitral valve repair versus replacement

BACKGROUND

Rheumatic mitral valve repair and replacement techniques are frequently used with excellent outcomes in experienced centers. This study aims to evaluate the impact of procedural types on left ventricular function in quinquagenarians.

METHODS

Between January 2018 and September 2019, patients with severe rheumatic mitral stenosis were prospectively recruited. Propensity score matching was performed to reduce the selection bias. We compared the strain, twist and synchrony parameters of left ventricle in 70 quinquagenarian patients who underwent rheumatic mitral valve repair and replacement 12 hours before surgery, at 7 days and 6 months postoperatively.

RESULTS

The overall group displayed significant improvement of left ventricular deformation after rheumatic mitral valve surgery. Compared with patients undergoing posterior chordal-sparing mitral valve replacement, patients undergoing rheumatic mitral valve repair showed more significant amelioration in global longitudinal strain (-18.6% versus -16.2%, P<0.001), twist (18.2° versus 15.9°, P<0.001), torsion (1.8°/cm versus 1.3°/cm, P<0.001), apical rotation (10.5° versus 8.8°, P<0.001), basal rotation (-7.7° versus -7.1°, P=0.049), systolic dyssynchrony index (4.7% versus 5.1%, P=0.021), standard deviation of time to peak longitudinal (46.9 ms versus 49.3 ms, P=0.024) and radial strain (15.8 ms versus 17.1 ms, P=0.037) at 6-month follow-up.

CONCLUSIONS

Rheumatic mitral valve repair might provide patients with better postoperative left ventricular performance than posterior chordal-sparing mitral valve replacement. Longer follow-up is required to compare long-term outcomes.

Regional Left Ventricular Myocardial Dysfunction After Cardiac Surgery Characterized by 3-Dimensional Strain

BACKGROUND

Three-dimensional (3D) strain is an echocardiographic modality that can characterize left ventricular (LV) function with greater accuracy than ejection fraction. While decreases in global strain have been used to predict outcomes after cardiac surgery, changes in regional 3D longitudinal, circumferential, radial, and area strain have not been well described. The primary aim of this study was to define differential patterns in regional LV dysfunction after cardiac surgery using 3D speckle tracking strain imaging. Our secondary aim was to investigate whether changes in regional strain can predict postoperative outcomes, including length of intensive care unit stay and 1-year event-free survival.

METHODS

In this prospective clinical study, demographic, operative, echocardiographic, and clinical outcome data were collected on 182 patients undergoing aortic valve replacement, mitral valve repair or replacement, coronary artery bypass graft, and combined cardiac surgery. Three-dimensional transthoracic echocardiograms were performed preoperatively and on the second to fourth postoperative day. Blinded analysis was performed for LV regional longitudinal, circumferential, radial, and area strain in the 17-segment model.

RESULTS

Regional 3D longitudinal, circumferential, radial, and area strains were associated with differential patterns of myocardial dysfunction, depending on the surgical procedure performed and strain measure. Patients undergoing mitral valve repair or replacement had reduced function in the majority of myocardial segments, followed by coronary artery bypass graft, while patients undergoing aortic valve replacement had reduced function localized only to apical segments. After all types of cardiac surgery, segmental function in apical segments was reduced to a greater extent as compared to basal segments. Greater decrements in regional function were seen in circumferential and area strain, while smaller decrements were observed in longitudinal strain in all surgical patients. Both preoperative regional strain and change in regional strain preoperatively to postoperatively were correlated with reduced 1-year event-free survival, while postoperative strain was not predictive of outcomes. Only preoperative strain values were predictive of intensive care unit length of stay.

CONCLUSIONS

Changes in regional myocardial function, measured by 3D strain, varied by surgical procedure and strain type. Differences in regional LV function, from presurgery to postsurgery, were associated with worsened 1-year event-free survival. These findings suggest that postoperative changes in myocardial function are heterogeneous in nature, depending on the surgical procedure, and that these changes may have long-term impacts on outcome. Therefore, 3D regional strain may be used to identify patients at risk for worsened postoperative outcomes, allowing early interventions to mitigate risk.

Correlation and agreement between 2D and 3D speckle-tracking echocardiography for left ventricular volumetric, strain, and rotational parameters in healthy volunteers and in patients with mild mitral stenosis

BACKGROUND

Recent advances had allowed measurement of myocardial deformation parameters using 3D speckle-tracking echocardiography (STE). Agreement between these two modalities and interchangeability of findings remain as an issue since 2DSTE is more widely available than 3DSTE. The aim of this study was to investigate the correlation and agreement between 2DSTE and 3DSTE in healthy volunteers and in patients with mild mitral stenosis (MS).

METHODS

Data from 31 patients with mild MS and 27 healthy volunteers were included in this study. Data were analyzed for the correlation and agreement between 2DSTE and 3DSTE for volumetric, strain, and rotational parameters.

RESULTS

There were no significant differences between 2DSTE and 3DSTE in both control and MS groups for left ventricular volumetric and rotational parameters. 3D global longitudinal strain (GLS) and global circumferential strain (GCS) were significantly higher in healthy volunteers (P < 0.001 for both), while only 3DGCS was significantly higher than 2DGCS in MS group (P < 0.001). The correlation between 3DSTE and 2DSTE was weak-to-moderate in both groups for strain and rotational parameters, and overall, correlation coefficients were higher in MS group. An exception was GLS in MS group, where coefficient of correlation was excellent (r = 0.907). Agreement between two modalities was poor for strain and rotational parameters, and the average bias was high.

CONCLUSIONS

Overall, the agreement between 2DSTE and 3DSTE for strain and rotational measures was poor with a high average bias. The agreement between 2DSTE and 3DSTE is affected by the presence of underlying MS and the direction of strain.