Prediction of subclinical left ventricular dysfunction with strain rate imaging in patients with mild to moderate rheumatic mitral stenosis

Recommendations for the Use of Echocardiography in the Evaluation of Rheumatic Heart Disease: A Report from the American Society of Echocardiography

Acute rheumatic fever and its chronic sequela, rheumatic heart disease (RHD), pose major health problems globally, and remain the most common cardiovascular disease in children and young people worldwide. Echocardiography is the most important diagnostic tool in recognizing this preventable and treatable disease and plays an invaluable role in detecting the presence of subclinical disease needing prompt therapy or follow-up assessment. This document provides recommendations for the comprehensive use of echocardiography in the diagnosis and therapeutic intervention of RHD. Echocardiographic diagnosis of RHD is made when typical findings of valvular and subvalvular abnormalities are seen, including commissural fusion, leaflet thickening, and restricted leaflet mobility, with varying degrees of calcification. The mitral valve is predominantly affected, most often leading to mitral stenosis. Mixed valve disease and associated cardiopulmonary pathology are common. The severity of valvular lesions and hemodynamic effects on the cardiac chambers and pulmonary artery pressures should be rigorously examined. It is essential to take advantage of all available modalities of echocardiography to obtain accurate anatomic and hemodynamic details of the affected valve lesion(s) for diagnostic and strategic pre-treatment planning. Intraprocedural echocardiographic guidance is critical during catheter-based or surgical treatment of RHD, as is echocardiographic surveillance for post-intervention complications or disease progression. The role of echocardiography is indispensable in the entire spectrum of RHD management.

Comprehensive echocardiographic and speckle tracking strain analysis in rheumatic mitral stenosis patients before and after transvenous mitral commissurotomy

Percutaneous Transvenous Mitral Commissurotomy (PTMC) is the first line treatment for rheumatic mitral stenosis (MS). We sought to evaluate (1) changes in 2-dimensional (2D) echocardiographic and strain values and (2) differences in these values for patients in atrial fibrillation (AF) and sinus rhythm (SR) pre, immediately and 6 months post PTMC. Retrospective study of 136 patients who underwent PTMC between 2011 and 2021. We analyzed their 2D echocardiogram, Global Longitudinal Strain (GLS), Left Atrial Reservoir Strain (LAr-S) and Right Ventricle Free Wall Strain (RVFW-S) pre, immediately and 6 months post PTMC. At 6 months, mitral valve area increases from 0.94 ± 0.23 cm2 to 1.50 ± 0.42 cm2. Ejection fraction (EF) did not change post PTMC (pre; 55.56 ± 6.62%, immediate; 56.68 ± 7.83%, 6 months; 56.28 ± 7.00%, p = 0.218). Even though EF is preserved, GLS is lower pre-procedure; - 11.52 ± 3.74% with significant improvement at 6 months; - 15.16 ± 4.28% (p < 0.001). Tricuspid annular plane systolic excursion (TAPSE) improved at 6 months from 1.95 ± 0.43 to 2.11 ± 0.49 (p = 0.004). RVFW-S increases at 6 months from - 17.37 ± 6.03% to - 19.75 ± 7.19% (p = 0.011). LAr-S improved from 11.23 ± 6.83% pre PTMC to 16.80 ± 8.82% at 6 months (p < 0.001) post PTMC. Pre-procedure patients with AF have lower strain values (More LV, RV and LA dysfunction) with statistically significant difference for LAr-S (p < 0.001), GLS (p < 0.001) and RVFW-S (p < 0.001) than patients in SR. Patients with severe rheumatic MS have subclinical left and right ventricle dysfunction despite preserved EF and relatively normal TAPSE with significant improvement seen at 6 months post PTMC. AF patients have lower baseline strain values than SR patients.

Left Ventricular Remodeling Following Balloon Mitral Valvuloplasty in Rheumatic Mitral Stenosis: Magnetic Resonance Imaging Study

Background: Rheumatic heart disease affects primarily cardiac valves, it could involve the myocardium either primarily or secondary to heart valve affection. The influence of balloon mitral valvuloplasty (BMV) on left ventricular function has not been sufficiently studied. Aim: To determine the influence of balloon mitral valvuloplasty (BMV) on both global and regional left ventricular (LV) function. Methods: Thirty patients with isolated rheumatic mitral stenosis (MS) were studied. All patients had cardiac magnetic resonance imaging (CMR) before, 6 months and 1 year after successful BMV. LV volumes, ejection fraction (EF), regional and global LV deformation, and LV late gadolinium enhancement were evaluated. Results: At baseline, patients had median EF of 57 (range: 45-69) %, LVEDVI of 74 (44-111) ml/m2 and LVESVI of 31 (14-57) ml/m2 with absence of late gadolinium enhancement in all myocardial segments. Six months following BMV, there was a significant increase in LV peak systolic global longitudinal strain (GLS) (-16.4 vs. -13.8, p < 0.001) and global circumferential strain (GCS) (-17.8 vs. -15.6, p = 0.002). At 1 year, there was a trend towards decrease in LVESVI (29 ml/m2, p = 0.079) with a significant increase in LV EF (62%, p < 0.001). A further significant increase, compared to 6 months follow up studies, was noticed in GLS (-17.9 vs. -16.4, p = 0.008) and GCS (-19.4 vs. -17.8 p = 0.03). Conclusions: Successful BMV is associated with improvement in global and regional LV systolic strain which continues for up to 1 year after the procedure.

Impact of balloon mitral valvuloplasty on left ventricular rotational deformation: Magnetic Resonance Imaging follow up study

In patients with rheumatic mitral stenosis (MS), some previous studies have investigated the influence of balloon mitral valvuloplasty (BMV) on left ventricular (LV) systolic function. However, the impact of BMV on LV twisting motion in this clinical setting has not been studied before yet. To describe changes in LV torsion in patients with rheumatic MS following BMV. Thirty patients (median age 33 years, 22 women) with isolated severe MS were studied. CMR myocardial tissue tagging was used for assessment of LV rotational deformation. LV torsion was calculated as the twist value (the net difference between apical counterclockwise and basal clockwise rotation) normalized to the length of the ventricle and multiplied by the mean radius at the base and apex. All patients had CMR studies before, 6 months and 1 year after successful BMV. At baseline, patients had a mitral valve area of 0.9 (0.6-1.3) cm², mean pressure gradient of 12.5 (8-24) mmHg across the valve as measured by transthoracic echocardiography. Median LV ejection fraction (LVEF) estimated by CMR was 57 (range: 45-69) %. A significant improvement in LV base-apex torsion was shown at 6 months (3.3° vs. 2.5°, p < 0.001) with a further improvement at 1 year (4.1° vs. 3.3°, p = 0.05). Similar pattern of change was seen in LV base-mid torsion with a significant increase at 6 months (3.6° vs. 2.3°, p < 0.001) and a further increase at 1 year (4.7° vs. 3.6°, p = 0.007). These changes were associated with a significant increase in LVEF (62% vs. 57%, p < 0.001) at 1 year following BMV. Successful BMV is associated with a significant improvement in LV torsion that is accompanied by a significant improvement in LVEF.

Subclinical left ventricular systolic dysfunction in diabetic patients and its association with retinopathy: A 2D speckle tracking echocardiography study

AIM

It is important to diagnose diabetic cardiomyopathy in the early stages to prevent development of evident heart failure in the future. The primary objective of this study was to evaluate the presence of subclinical left ventricular (LV) dysfunction with two-dimensional (2D) speckle tracking echocardiography (STE) and the secondary objective was to compare retinopathy-positive and -negative diabetic patients.

PATIENTS AND METHODS

A total of 82 patients with type II diabetes mellitus (DM) and 90 gender-matched healthy controls were included. Retinopathy was present in 55 patients in the study group. All study participants underwent conventional 2D echocardiography and STE.

RESULTS

All diabetic patients had preserved LV ejection fraction (LV-EF ≥ 50). Compared with the control group, diabetic patients had a larger left atrium (47.3 ± 19.9 mm vs. 36.9 ± 17.8 mm, p < 0.001) and a higher E/Em ratio (12.0 ± 2.9 vs. 10.5 ± 3.7, p = 0.004). The LV-EF, LV end diastolic and end systolic volumes, E/A ratios, deceleration times, and tissue Doppler parameters were compared between groups. The study group was observed to have statistically significant lower four-chamber (4C; 17.7 ± 3.0 % vs. 19.3 ± 3.5 %, p = 0.002), three-chamber (3C; 17.5 ± 3.0 % vs. 19.2 ± 3.4 %, p = 0.001), and two-chamber (2C; 18.5 ± 3.5 % vs. 20.1 ± 2.4 %, p = 0.001) peak longitudinal strain values compared with the control group. Moreover, LV global strain values were found to be significantly lower in the DM group than in the control group (17.9 ± 2.7 % vs. 21.1 ± 3.2 %, p < 0.001). By contrast, basal rotation (4.9 ± 3.3° vs.2.8 ± 4.5°, p = 0.001), apical rotation (15.3 ± 6.7° vs. 12.1 ± 5.3°, p = 0.001) and LV twist (20.2 ± 7.2° vs. 16.9 ± 6.5°, p = 0.002) in the DM group were significantly increased compared with those of controls.

CONCLUSION

The STE procedure can be a useful novel technique in the determination of subclinical LV dysfunction in diabetic patients. Diabetic patients have lower longitudinal myocardial mechanics, and circumferential and rotational mechanics are impaired. There was no significant association between diabetic retinopathy and LV function.

Severity of mitral stenosis and left ventricular mechanics: a speckle tracking study

BACKGROUND

It has been shown that mitral stenosis (MS) impairs left ventricular (LV) systolic function; however, this issue has not been studied comprehensively. We aimed to evaluate the role of 2D strain in the assessment of subclinical LV systolic dysfunction in patients with MS.

METHODS

Seventy-two patients with isolated MS (mild, moderate and severe) and 31 healthy control subjects constituted the study population. 2D echocardiography images were obtained from LV apical 4-chamber (4C), long axis (LAX), and 2-chamber (2C) views. Peak longitudinal strain and strain rate (Sr) were obtained from 4C, LAX, and 2C views. Global strain and Sr were calculated by averaging the three apical views.

RESULTS

There were no significant differences in LV ejection fraction and LV systolic or diastolic dimensions between the groups. Patients with MS had significantly lower LV longitudinal strain and Sr measurements than the control group. In addition, there were no significant differences in MS subgroups with respect to LV strain and Sr measurements.

CONCLUSION

We demonstrated that patients with MS had lower LV functions using 2D strain imaging, and this is independent of the hemodynamic severity of MS. In the detection of subclinical LV dysfunction in patients with MS, 2D strain imaging appears to be useful.

Fragmented QRS is predictive of myocardial dysfunction, pulmonary hypertension and severity in mitral stenosis

Reliable non-invasive new indices reflecting severity of rheumatic valve disease would be highly beneficial. Recently, presence of fragmented QRS (fQRS) in ECG was accepted as a marker of myocardial fibrosis. fQRS is defined as the presence of RSR' patterns such as additional R wave (R'), notching in the R wave or the S wave in 2 contiguous leads. Purpose of our study was to establish frequency of fQRS in isolated rheumatic mitral stenosis compared with control group. We studied 193 patients with mitral stenosis and age/gender matched 97 healthy subjects. Patients were categorized according to the New York Heart Association (NYHA) functional class. Severity of mitral stenosis, left ventricular ejection fraction, and pulmonary artery pressure were obtained by means of echocardiography. fQRS was defined on routine 12-lead ECG. fQRS was more frequent in subjects with mitral stenosis than in control group (p < 0.001). fQRS was associated with low ejection fraction, pulmonary hypertension, poor functional NYHA class, increased mean mitral valve gradient and decreased mitral valve area (R = 0.1, p = 0.02; R = 0.1, p = 0.001; R = 0.1, p = 0.01; R = 0.1, p = 0.04; and R = -0.1, p = 0.009, respectively). Mitral valve area was the only independent predictor of fQRS in multiple logistic regression analysis. In conclusion, fQRS is predictive of severe mitral stenosis, lower ejection fraction, increased pulmonary artery pressure, and poor functional class. fQRS might be considered as a novel indicator of mitral stenosis severity and associated complications.

Emerging clinical role of strain imaging in echocardiography

Myocardial strain is a measure of tissue deformation and strain rate is the rate at which deformation occurs. When applied to the heart, strain and strain rate give fundamental information on myocardial properties and mechanics that would otherwise be unavailable. Site specificity and angle independency are two unique characteristics of strain and strain rate data. Strain and strain rate can be obtained with tissue Doppler imaging or with 2D speck tracking. These two techniques derive information on strain and strain rate in two fundamentally different ways and each has its own advantages and limitations. Tissue Doppler imaging yields velocity information from which strain and strain rate are mathematically derived whereas 2D speckle tracking yields strain information from which strain rate and velocity data are derived. Data obtained from these two different techniques may not be equivalent due to limitations inherent with each technique. Strain and strain rate imaging have been used to assess myocardial function in a wide range of cardiac conditions. They are useful in detecting early left ventricular (LV) dysfunction in the setting of systemic diseases with cardiac involvement, in differentiating transmural from non-transmural infarction, and in identifying LV contractile reserve in regurgitant valve lesions. When used with dobutamine echocardiography, strain and strain rate imaging can identify viable myocardium and aid the detection of myocardial ischaemia. Strain and strain rate imaging can also be used to assess right ventricular and left atrial function. Despite significant promises, strain and strain rate imaging is technically challenging and signal to noise ratio may be potentially affected by a wide range of factors. As a result, strain and strain rate imaging have been slow to get incorporated into everyday clinical practice. Ongoing research and further technical development are likely to improve the quality of the data and the more general acceptance of these new modalities of imaging in echocardiography.

Prediction of subclinical left ventricular dysfunction with longitudinal two-dimensional strain and strain rate imaging in patients with mitral stenosis

Longitudinal two-dimensional strain deformation is a novel technique which evaluates global and regional left ventricular (LV) function with high reproducibility. The aim of the study was to investigate the global and regional systolic function using this method in patients with pure mitral stenosis (MS). Conventional echocardiography and longitudinal two-dimensional strain analysis were performed in 60 patients (41 +/- 5 years, 48 women) with mild to moderate MS (mitral valve area: 1.9 +/- 0.5 cm(2)), and 52 healthy controls (40 +/- 7 years, 37 women). For strain analysis standard apical views were obtained, and by using a software system peak systolic strain and strain rate were calculated off-line in each segment. In all, 88% of the segments could be optimally tracked by the software system. Despite normal LV systolic function as assessed by ejection fraction (66 +/- 8%), mean global longitudinal strain (GLS) and global longitudinal strain rate (GLSR) were significantly reduced in patients with isolated MS (GLS -17 +/- 3.3 vs. -19 +/- 2.5%, P = 0.006 and GLSR -1.3 +/- 0.3 vs. -1.5 +/- 0.3 s(-1), P < 0.0001). Regional analysis demonstrated that patients with MS had a significantly reduced longitudinal peak strain and strain rate in all basal, and some mid (inferior, anteroseptal, interventricular septum) segments of the left ventricle. For other segments longitudinal peak strain and strain rate values were similar among the groups. Evaluation of LV systolic function by longitudinal two-dimensional strain deformation identified early abnormalities in MS patients who had apparently normal standard systolic function.

Mitral stenosis

Mitral stenosis is a common disease that causes substantial morbidity worldwide. The disease is most prevalent in developing countries, but is increasingly being identified in an atypical form in developed countries. All treatments that increase valve area improve morbidity. Mortality improves with surgery; the benefit of percutaneous balloon valvuloplasty to mortality might be similar to that of surgery but needs further study. Percutaneous balloon valvuloplasty is the treatment of choice for patients in whom treatment is indicated, except for those with suboptimum valve morphology, and even these patients are sometimes treated with this procedure if surgery is not feasible or if surgical risk is prohibitive. We review the pathology, diagnosis, and treatment options for patients with mitral stenosis.

Abnormal left ventricular longitudinal wall motion in rheumatic mitral stenosis before and after balloon valvuloplasty: a strain rate imaging study

Rheumatic mitral stenosis may be associated with left ventricular dysfunction. We report improvements of abnormal longitudinal wall motion and strain rate post-balloon valvuloplasty of severe mitral stenosis in a girl with normal ejection fraction.