Assessment of left ventricular dyssynchrony by speckle tracking strain imaging comparison between longitudinal, circumferential, and radial strain in cardiac resynchronization therapy

Blood volume contributes to the mechanical synchrony of the myocardium during moderate and high intensity exercise in women

PURPOSE

Whether blood volume (BV) primarily determines the synchronous nature of the myocardium remains unknown. This study determined the impact of standard blood withdrawal on left ventricular mechanical dyssynchrony (LVMD) in women.

METHODS

Transthoracic speckle-tracking echocardiography and central hemodynamic measurements were performed at rest and during moderate- to high-intensity exercise in healthy women (n = 24, age = 53.6 ± 16.3 year). LVMD was determined via the time to peak standard deviation (TPSD) of longitudinal and transverse strain and strain rates (LSR, TSR). Measurements were repeated within a week period immediately after a 10% reduction of BV.

RESULTS

With intact BV, all individuals presented cardiac structure and function variables within normative values of the study population. Blood withdrawal decreased BV (5.3 ± 0.7 L) by 0.5 ± 0.1 L. Resting left ventricular (LV) end-diastolic volume (- 8%, P = 0.040) and passive filling (- 16%, P = 0.001) were reduced after blood withdrawal. No effect of blood withdrawal was observed for any measure of LVMD at rest (P ≥ 0.225). During exercise at a fixed submaximal workload (100 W), LVMD of myocardial longitudinal strain (LS TPSD) was increased after blood withdrawal (36%, P = 0.047). At peak effort, blood withdrawal led to increased LVMD of myocardial transverse strain rate (TSR TPSD) (31%, P = 0.002). The effect of blood withdrawal on TSR TPSD at peak effort was associated with LV concentric remodeling (r = 0.59, P = 0.003).

CONCLUSION

Marked impairments in the mechanical synchrony of the myocardium are elicited by moderate blood withdrawal in healthy women during moderate and high intensity exercise.

Left bundle branch pacing better preserves ventricular mechanical synchrony than right ventricular pacing: a two-centre study

AIMS

Left bundle branch pacing (LBBP) has been shown to better maintain electrical synchrony compared with right ventricular pacing (RVP), but little is known about its impact on mechanical synchrony. This study investigates whether LBBP better preserves left ventricular (LV) mechanical synchronicity and function compared with RVP.

METHODS AND RESULTS

Sixty patients with pacing indication for bradycardia were included: LBBP (n = 31) and RVP (n = 29). Echocardiography was performed before and shortly after pacemaker implantation and at 1-year follow-up. The lateral wall-septal wall (LW-SW) work difference was used as a measure of mechanical dyssynchrony. Septal flash, apical rocking, and septal strain patterns were also assessed. At baseline, LW-SW work difference was small and similar in two groups. SW was markedly decreased, while LW work remained mostly unchanged in RVP, resulting in a larger LW-SW work difference compared with LBBP (1253 ± 687 mmHg·% vs. 439 ± 408 mmHg·%, P < 0.01) at last follow-up. In addition, RVP more often induced septal flash or apical rocking and resulted in more advanced strain patterns compared with LBBP. At 1 year follow-up, LV ejection fraction (EF) and global longitudinal strain (GLS) were more decreased in RVP compared with LBBP (ΔLVEF: -7.4 ± 7.0% vs. 0.3 ± 4.1%; ΔLVGLS: -4.8 ± 4.0% vs. -1.4 ± 2.5%, both P < 0.01). In addition, ΔLW-SW work difference was independently correlated with LV adverse remodelling (r = 0.42, P < 0.01) and LV dysfunction (ΔLVEF: r = -0.61, P < 0.01 and ΔLVGLS: r = -0.38, P = 0.02).

CONCLUSION

LBBP causes less LV mechanical dyssynchrony than RVP as it preserves a more physiologic electrical conduction. As a consequence, LBBP appears to preserve LV function better than RVP.

Assessment of myocardial strain patterns in patients with left bundle branch block using cardiac magnetic resonance

Recently, a classification with four types of septal longitudinal strain patterns was described using echocardiography, suggesting a pathophysiological continuum of left bundle branch block (LBBB)-induced left ventricle (LV) remodeling. The aim of this study was to assess the feasibility of classifying these strain patterns using cardiovascular magnetic resonance (CMR), and to evaluate their association with LV remodeling and myocardial scar. Single center registry included LBBB patients with septal flash (SF) referred to CMR to assess the cause of LV systolic dysfunction. Semi-automated feature-tracking cardiac resonance (FT-CMR) was used to quantify myocardial strain and detect the four strain patterns. A total of 115 patients were studied (age 66 ± 11 years, 57% men, 28% with ischemic heart disease). In longitudinal strain analysis, 23 patients (20%) were classified in stage LBBB-1, 37 (32.1%) in LBBB-2, 25 (21.7%) in LBBB-3, and 30 (26%) in LBBB-4. Patients at higher stages had more prominent septal flash, higher LV volumes, lower LV ejection fraction, and lower absolute strain values (p < 0.05 for all). Late gadolinium enhancement (LGE) was found in 55% of the patients (n = 63). No differences were found between the strain patterns regarding the presence, distribution or location of LGE. Among patients with LBBB, there was a good association between strain patterns assessed by FT-CMR analysis and the degree of LV remodeling and LV dysfunction. This association seems to be independent from the presence and distribution of LGE.

Left Atrial Mechanical Function And Stiffness In Patients With Premature Ventricular Contraction: A Speckle Tracking Study

AIM

Ventricular extrasystole (PVC) is characterized by premature ventricular depolarization and is associated with increased risk of arrhythmias and structural heart disease. This study aimed to investigate the association between the PVC burden and left atrial (LA) function in individuals without known cardiac disease.

MATERIAL AND METHODS

A cross-sectional study was conducted on 102 patients with PVCs who were admitted to a cardiology clinic. Transthoracic echocardiography was used to assess left ventricle (LV) parameters, including LV mass, LV ejection fraction (LVEF), LV global longitudinal strain (LVGLS), and LA function was evaluated using strain imaging. The PVC burden was categorized into three groups: <10 %, 10-20 %, and >20 %.

RESULTS

Changes in LV dimensions and LV mass index were associated with the groups with the PVC burden with 10-20 %, and >20 %. but differences in LVEF and LVGSL were not significant. Mean E / e' increased as the PVC burden increased (p<0.001). The mean global LA peak strain decreased as the PVC burden increased (p<0.001), while other mean LA measurements increased as the PVC burden increased (p<0.001) A higher PVC burden was associated with impaired LA function, as indicated by decreased global LA peak strain (PVC burden <10 %=38.1±3.2 vs. PVC burden 10-20 %=32.4±3.2 vs. PVC burden >20 %=27.7±2.6, in all groups p<0.001) and with increased LA stiffness (PVC burden <10 %=18.6±3.2 vs. PVC burden 10-20 %=27.5±5.5 vs. PVC burden >20 %=39.0±7.9, in all groups p<0.001). A strong negative correlation was found between global LA peak strain and LA stiffness (r=-0.779, p<0.001).

CONCLUSION

In individuals without known cardiac disease, a higher PVC burden was associated with impaired LA function, indicated by increased E / e', decreased LA strain, and increased LA stiffness. These findings suggest that PVC burden may contribute to LA dysfunction, potentially increasing the risk of cardiovascular events.

Sex-specific difference in cardiac function in patients with systemic sclerosis: association with cardiovascular outcomes

BACKGROUND

Cardiovascular involvement is one of the leading causes of mortality in systemic sclerosis (SSc) and is reported to be higher in men as compared with women. However, the cause of this difference is largely unknown. The objective of this study was to assess sex differences in echocardiographic characteristics, including left ventricular global longitudinal strain (LV GLS), as a potential explanation of sex differences in outcomes.

METHODS

A total of 746 patients with SSc from four centres, including 628 (84%, 54±13 years) women and 118 (16%, 55±15 years) men, were evaluated with standard and advanced echocardiographic examinations. The independent association of the echocardiographic parameters with the combined endpoint of cardiovascular events-hospitalisation/death was evaluated.

RESULTS

Men and women with SSc showed significant differences in disease characteristics and cardiac function. After adjusting for the most important clinical characteristics, while LV ejection fraction and diastolic function were not significantly different anymore, men still presented with more impaired LV GLS as compared with women (-19% (IQR -20% to -17%) vs -21% (IQR: -22% to -19%), p<0.001). After a median follow-up of 48 months (IQR: 26-80), the combined endpoint occurred in 182 patients. Men with SSc experienced higher cumulative rates of cardiovascular events-hospitalisation/mortality (χ2=8.648; Log-rank=0.003), and sex differences were maintained after adjusting for clinical confounders, but neutralised when matching the groups for LV GLS.

CONCLUSION

In patients with SSc, male sex is associated with worse cardiovascular outcomes even after adjusting for important clinical characteristics. LV GLS was more impaired in men as compared with women and potentially explains the sex difference in cardiovascular outcomes.

Cardiovascular imaging in conduction system pacing: What does the clinician need?

Permanent pacemakers are used for symptomatic bradycardia and biventricular pacing (BVP)-cardiac resynchronization therapy (BVP-CRT) is established for heart failure (HF) patients traditionally. According to guidelines, patients' selection for CRT is based on QRS duration (QRSd) and morphology by surface electrocardiogram (ECG). Cardiovascular imaging techniques evaluate cardiac structure and function as well as identify pathophysiological substrate changes including the presence of scar. Cardiovascular imaging helps by improving the selection of candidates, guiding left ventricular (LV) lead placement, and optimization devices during the follow-up. Conduction system pacing (CSP) includes His bundle pacing (HBP) and left bundle branch pacing (LBBP) which is screwed into the interventricular septum. CSP maintains and restores ventricular synchrony in patients with native narrow QRSd and left bundle branch block (LBBB), respectively. LBBP is more feasible than HBP due to a wider target area. This review highlights the role of multimodality cardiovascular imaging including fluoroscopy, echocardiography, cardiac magnetic resonance (CMR), myocardial scintigraphy, and computed tomography (CT) in the pre-procedure assessment for CSP, better selection for CSP candidates, the guidance of CSP lead implantation, and the optimization of devices programming after the procedure. We also compare the different characteristics of multimodality imaging and discuss their potential roles in future CSP implantation.

Response rate in cardiac resynchronization therapy patients implanted with a left ventricular quadripolar lead and the MultiPoint™ pacing feature early activated. QUARTO III

BACKGROUND

Although cardiac resynchronization therapy (CRT) is beneficial in most heart failure patients, up to 40% do not respond to CRT. It has been suggested that multipoint left ventricle pacing (MPP) would increase the response rate.

AIM

To assess the CRT response rate at 6 months in patients implanted with a CRT device with the MPP feature activated early after the implant.

METHODS

This was a multicentre, prospective, open-label and non-randomized study. The primary endpoint was response to biventricular pacing defined as >15% relative reduction in left ventricular end-systolic volume (LVESV) comparing echocardiography measurements performed at baseline and 6 months by a core laboratory. Among secondary endpoints the combined endpoint of mortality or all-cause hospitalizations was evaluated. Primary study endpoint and clinical outcomes were compared to a Quarto II control cohort.

RESULTS

Totally, 105 patients were included. The response rate was 64.6% (97.5% lower confidence bound 53%). Mean relative reduction in LVESV was 25.3%, and mean absolute increase in LVEF was 9.4%. The subjects with device programmed using anatomical approach showed a trend towards higher responder rate than those using the electrical approach (72% vs. 61.1%, p = 0.32). Finally, the combined incidence of mortality and or all-cause hospitalizations at 6 month was 12.4%.

CONCLUSIONS

Early activation of MPP was not associated to an advantage increasing echocardiography responders to CRT at 6 months of follow-up. Nevertheless, patients programmed using widest pacing cathodes had a numerically higher responder rate. Finally, early activation of MPP was associated to a low incidence of clinical endpoints at 6 months of follow-up.

Impaired cardiac mechanical synchrony revealed with increased myocardial work in women with advanced age

BACKGROUND

Whether the synchronous nature of the myocardium is sex-dependent or affected by the aging process remains unknown. This study aimed to determine the influence of sex and age on cardiac mechanical synchrony during controlled hemodynamic stress.

METHODS

Transthoracic speckle-tracking echocardiography analyses and central hemodynamics were assessed at rest and during moderate- to high-intensity exercise in healthy young (<45 yr) and older (≥45 yr) women (n = 32) and men (n = 34) matched by age, physical activity and exercise capacity. Left ventricular mechanical dyssynchrony (LVMD) was determined as the time to peak standard deviation (TPSD) of longitudinal and transverse strain and strain rates (LSR, TSR).

RESULTS

Physical activity, aerobic capacity, heart rate, blood pressure and LVMD at rest were similar between women and men in each age group (P > 0.05). The rate pressure product, an index of myocardial work, did not differ between sex and age groups at rest and during exercise at a given percentage of peak heart rate (P > 0.05). A consistent age effect was observed for transverse LVMD (P-for-age ≤ 0.011). Specifically, older women presented with marked increments (≥42 %) in TSR TPSD at all exercise levels compared with younger women (P ≤ 0.005). Sex per se did not generally affect LVMD.

CONCLUSION

A prevailing impairment of cardiac mechanical synchrony in the transverse axis of the left ventricle is revealed during conditions of elevated hemodynamic stress in women with advanced age.

Preliminary Feasibility of Stress Myocardial Elastography for the Detection of Coronary Artery Disease

Myocardial elastography (ME) is a cardiac strain imaging technique that has been found capable of detecting a decrease in radial strain caused by ischemia or infarction in patients with coronary artery disease (CAD) as well as in a canine model. Prior studies have focused on rest imaging, but stress testing can reveal functional deficits caused by stenoses that are asymptomatic at rest. Therefore, it has been proposed that stress ME (S-ME) improves the detection of CAD. A novel strain difference (Δε) metric is presented and investigated in a canine model of induced ischemia, as well as in a study in human patients with CAD validated by myocardial perfusion imaging. In the canine model study, flow-limiting stenosis was induced by partial ligation in n = 2 canines, and stenosis was found to consistently reduce Δε in the affected myocardial regions compared with baseline, as well as compared to myocardial regions that are remote to the induced stenosis. In the clinical study, the median Δε was significantly lower (p < 0.05) in infarcted myocardial regions (-6.29%) than in those with normal perfusion (4.62%), with Δε in ischemic regions falling in between (-2.91%). The same trend was observed when considering radial strain during stress and, to a lesser degree, at rest alone. The results indicate that S-ME may be more sensitive to mild cases of CAD that are functionally asymptomatic at rest.

Myocardial Work in Echocardiography

Myocardial work is an emerging tool in echocardiography that incorporates left ventricular afterload into global longitudinal strain analysis. Myocardial work correlates with myocardial oxygen consumption, and work efficiency can also be assessed. Myocardial work has been evaluated in a variety of clinical conditions to assess the added value of myocardial work compared to left ventricular ejection fraction and global longitudinal strain. This review showcases the current use of myocardial work in adult echocardiography and its possible role in cardiac pathologies.

Left Ventricular "Longitudinal Rotation" and Conduction Abnormalities-A New Outlook on Dyssynchrony

BACKGROUND

The complete left bundle branch block (CLBBB) results in ventricular dyssynchrony and a reduction in systolic and diastolic efficiency. We noticed a distinct clockwise rotation of the left ventricle (LV) in patients with CLBBB ("longitudinal rotation").

AIM

The aim of this study was to quantify the "longitudinal rotation" of the LV in patients with CLBBB in comparison to patients with normal conduction or complete right bundle branch block (CRBBB).

METHODS

Sixty consecutive patients with normal QRS, CRBBB, or CLBBB were included. Stored raw data DICOM 2D apical-4 chambers view images cine clips were analyzed using EchoPac plugin version 203 (GE Vingmed Ultrasound AS, Horten, Norway). In EchoPac-Q-Analysis, 2D strain application was selected. Instead of apical view algorithms, the SAX-MV (short axis-mitral valve level) algorithm was selected for analysis. A closed loop endocardial contour was drawn to initiate the analysis. The "posterior" segment (representing the mitral valve) was excluded before finalizing the analysis. Longitudinal rotation direction, peak angle, and time-to-peak rotation were recorded.

RESULTS

All patients with CLBBB (n = 21) had clockwise longitudinal rotation with mean four chamber peak rotation angle of -3.9 ± 2.4°. This rotation is significantly larger than in patients with normal QRS (-1.4 ± 3°, p = 0.005) and CRBBB (0.1 ± 2.2°, p = 0.00001). Clockwise rotation was found to be correlated to QRS duration in patients with the non-RBBB pattern. The angle of rotation was not associated with a lower ejection fraction or the presence of regional wall abnormalities.

CONCLUSIONS

Significant clockwise longitudinal rotation was found in CLBBB patients compared to normal QRS or CRBBB patients using speckle-tracking echocardiography.

Dyssynchronous Heart Failure: A Clinical Review

PURPOSE OF THE REVIEW

Dyssynchrony occurs when portions of the cardiac chambers contract in an uncoordinated fashion. Ventricular dyssynchrony primarily impacts the left ventricle and may result in heart failure. This entity is recognized as a major contributor to the development and progression of heart failure. A hallmark of dyssynchronous heart failure (HF_d) is left ventricular recovery after dyssynchrony is corrected. This review discusses the current understanding of pathophysiology of HF_d and provides clinical examples and current techniques for treatment.

RECENT FINDINGS

Data show that HF_d responds poorly to medical therapy. Cardiac resynchronization therapy (CRT) in the form of conventional biventricular pacing (BVP) is of proven benefit in HF_d, but is limited by a significant non-responder rate. Recently, conduction system pacing (His bundle or left bundle branch area pacing) has also shown promise in correcting HF_d. HF_d should be recognized as a distinct etiology of heart failure; HF_d responds best to CRT.

Does types of atrial fibrillation matter in the impairment of global and regional left ventricular mechanics and intra-ventricular dyssynchrony?

Background

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, which is associated with cardiac dysfunction. This study aimed to compare the impairment severity of left ventricular strain and intra-ventricular dyssynchrony using echocardiography-derived velocity vector imaging in patients with different types of AF without heart failure.

Methods

168 non-valvular AF patients with normal left ventricular ejection fraction (98 paroxysmal AF patients and 70 persistent AF patients) and 86 healthy control subjects were included in this study. Regional and global left ventricular longitudinal and circumferential strain were measured. Time to regional peak longitudinal strain was measured and the standard deviation of all 12 segments (SDT-S) was used as a measure of intra-ventricular dyssynchrony.

Results

Significantly lower GLS (−18.71 ± 3.00% in controls vs. −17.10 ± 3.01% in paroxysmal AF vs. −12.23 ± 3.25% in persistent AF, P &lt; 0.05) and GCS (−28.75 ± 6.34% in controls vs. −24.43 ± 6.86% in paroxysmal AF vs. −18.46 ± 6.42% in persistent AF, P &lt; 0.01) were observed in either persistent AF subjects or paroxysmal AF subjects compared with healthy control subjects (P &lt; 0.05). The impairment was much worse in persistent AF subjects compared with paroxysmal AF subjects (P &lt; 0.001). Intraventricular dyssynchrony was found in both persistent AF patients and paroxysmal AF patients, and it’s worse in persistent AF patients (52 ± 18 ms in controls, 61 ± 17 ms in paroxysmal AF, and 70 ± 28 ms in persistent AF, P &lt; 0.05). Multivariate regression analysis revealed AF types were independent risk factors of GLS, GCS, and intraventricular dyssynchrony.

Conclusion

AF types were not only associated with impaired longitudinal and circumferential left ventricle mechanics but also intra-ventricular mechanical dyssynchrony. Worse systolic mechanics and intra-ventricular dyssynchrony were found in patients with persistent AF compared with these in patients with paroxysmal AF.

Myocardial Strain Evaluation with Cardiovascular MRI: Physics, Principles, and Clinical Applications

Myocardial strain is a measure of myocardial deformation, which is a more sensitive imaging biomarker of myocardial disease than the commonly used ventricular ejection fraction. Although myocardial strain is commonly evaluated by using speckle-tracking echocardiography, cardiovascular MRI (CMR) is increasingly performed for this purpose. The most common CMR technique is feature tracking (FT), which involves postprocessing of routinely acquired cine MR images. Other CMR strain techniques require dedicated sequences, including myocardial tagging, strain-encoded imaging, displacement encoding with stimulated echoes, and tissue phase mapping. The complex systolic motion of the heart can be resolved into longitudinal strain, circumferential strain, radial strain, and torsion. Myocardial strain metrics include strain, strain rate, displacement, velocity, torsion, and torsion rate. Wide variability exists in the reference ranges for strain dependent on the imaging technique, analysis software, operator, patient demographics, and hemodynamic factors. In anticancer therapy cardiotoxicity, CMR myocardial strain can help identify left ventricular dysfunction before the decline of ejection fraction. CMR myocardial strain is also valuable for identifying patients with left ventricle dyssynchrony who will benefit from cardiac resynchronization therapy. CMR myocardial strain is also useful in ischemic heart disease, cardiomyopathies, pulmonary hypertension, and congenital heart disease. The authors review the physics, principles, and clinical applications of CMR strain techniques. Online supplemental material is available for this article. ^©RSNA, 2022.

Left ventricular systolic motion pattern differs among patients with left bundle branch block patterns

The study aimed to investigate left ventricular (LV) motion pattern in patients with LBBB patterns including patients with pacemaker rhythm (PM), type B Wolff-Parkinson-White syndrome (B-WPW), premature ventricular complexes originating from the right ventricular outflow tract (RVOT-PVC), and complete left bundle branch block (CLBBB). Two-dimensional speckle tracking was used to evaluate peak value and time to peak value of the LV twist, LV apex rotation, and LV base rotation in patients with PM, B-WPW, RVOT-PVC, and CLBBB with normal LV ejection fraction, and in age-matched control subjects. The LV motion patterns were altered in all patients compared to the control groups. Patients with PM and CLBBB had a similar LV motion pattern with a reduced peak value of LV apex rotation and LV twist. Patients with B-WPW demonstrated the opposite trend in the reduction of LV rotation peak value, which was more dominant in the basal layer. The most impairment in the LV twist/rotation peak value was identified in patients with RVOT-PVC. Compared to the control group, the apical-basal rotation delay was prolonged in patients with CLBBB, followed by those with B-WPW, PM, and RVOT-PVC. The LV motion patterns were different among patients with different patterns of LBBB. CLBBB and PM demonstrated a reduction in LV twist/rotation that was pronounced in the apical layer, B-WPW showed a reduction in the basal layer, and RVOT-PVC in both layers. CLBBB had the most pronounced LV apical-basal rotation dyssynchrony.

Four-dimensional computed tomography of the left ventricle, Part II: Estimation of mechanical activation times

PURPOSE

We demonstrate the viability of a four-dimensional X-ray computed tomography (4DCT) imaging system to accurately and precisely estimate mechanical activation times of left ventricular (LV) wall motion. Accurate and reproducible timing estimates of LV wall motion may be beneficial in the successful planning and management of cardiac resynchronization therapy (CRT).

METHODS

We developed an anthropomorphically accurate in silico LV phantom based on human CT images with programmed septal-lateral wall dyssynchrony. Twenty-six temporal phases of the in silico phantom were used to sample the cardiac cycle of 1 s. For each of the 26 phases, 1 cm thick axial slabs emulating axial CT image volumes were extracted, 3D printed, and imaged using a commercially available CT scanner. A continuous dynamic sinogram was synthesized by blending sinograms from these static phases; the synthesized sinogram emulated the sinogram that would be acquired under true continuous phantom motion. Using the synthesized dynamic sinogram, images were reconstructed at 70 ms intervals spanning the full cardiac cycle; these images exhibited expected motion artifact characteristics seen in images reconstructed from real dynamic data. The motion corrupted images were then processed with a novel motion correction algorithm (ResyncCT) to yield motion corrected images. Five pairs of motion uncorrected and motion corrected images were generated, each corresponding to a different starting gantry angle (0 to 180 degrees in 45 degree increments). Two line profiles perpendicular to the endocardial surface were used to sample local myocardial motion trajectories at the septum and the lateral wall. The mechanical activation time of wall motion was defined as the time at which the endocardial boundary crossed a fixed position defined on either of the two line profiles while moving toward the center of the LV during systolic contraction. The mechanical activation times of these myocardial trajectories estimated from the motion uncorrected and the motion corrected images were then compared with those derived from the static images of the 3D printed phantoms (ground truth). The precision of the timing estimates was obtained from the five different starting gantry angle simulations.

RESULTS

The range of estimated mechanical activation times observed across all starting gantry angles was significantly larger for the motion uncorrected images than for the motion corrected images (lateral wall: 58 ± 15 ms vs 12 ± 4 ms, p < 0.005; septal wall: 61 ± 13 ms vs 13 ± 9 ms, p < 0.005).

CONCLUSIONS

4DCT images processed with the ResyncCT motion correction algorithm yield estimates of mechanical activation times of LV wall motion with significantly improved accuracy and precision. The promising results reported in this study highlight the potential utility of 4DCT in estimating the timing of mechanical events of interest for CRT guidance.

Pregnancy Complications Lead to Subclinical Maternal Heart Dysfunction—The Importance and Benefits of Follow-Up Using Speckle Tracking Echocardiography

Pregnancy complications such as gestational diabetes (GDM) and hypertensive disorders of pregnancy (HDP) are frequent and influence not only fetal outcomes but also the maternal cardiac function. GDM and HDP may act as a proxy for increased metabolic and cardiovascular risk later in life. Speckle tracking echocardiography (STE) is a relatively new imaging technique that provides more sensitive assessment than conventional echocardiography of the maternal cardiac function. Recent research suggests that STE can be used during pregnancy and postpartum as a useful method of early detection of subclinical maternal cardiac changes related to pregnancy complications, such as GDM and HDP, and as an indicator for future maternal cardiovascular disorders. The aim of this review was to underline the current value of STE in the follow-up protocol of high-risk pregnant women, as a mean for pre- and postpartum monitoring. A review of the literature was conducted in the PubMed database to select relevant articles regarding the association of STE changes and HDP or GDM in the prenatal and postpartum maternal evaluations. Both GDM and HDP are associated with subtle myocardial changes in shape, size and function; these preclinical cardiac changes, often missed by conventional evaluation, can be detected using STE. Left ventricular global circumferential strain might be an important predictor of maternal cardiovascular disorders and might help to define a high-risk group that requires regular monitoring later in life and timely intervention.

Radial strain imaging-guided lead placement for improving response to cardiac resynchronization therapy in patients with ischaemic cardiomyopathy: the raise cardiac resynchronization therapy trial

AIMS

To evaluate the benefit of speckle tracking radial strain imaging (STRSI)-guided left ventricular (LV) lead (LVL) positioning in cardiac resynchronization therapy (CRT) in patients (pts) with ischaemic cardiomyopathy with CRT indication.

METHODS AND RESULTS

We conducted a prospective randomized controlled trial. Patients were enrolled in nine centres with 2:1 randomization into two groups (guided vs. control). Patients underwent STRSI to identify the optimal LV position from six LV segments at midventricular level. Implantation via STRSI was attempted for recommended segment in the guided group only. Follow-up included echocardiography (6 months) and clinical evaluation (6 and 12 months). The primary endpoint was comparison % reduction in LV end-systolic volume at 6 months with baseline. Secondary endpoints included hospitalizations for heart failure and death, and improvement in additional echocardiographic measurements and quality of life score. A total of 172 patients (115 guided vs. 57 control) were enrolled. In the guided group, 60% of the implanted LV leads were adjudicated to be successfully located at the recommended segment, whereas in the control group 44% reached the best STRSI determined segment. There was no difference between the groups in any of the primary or secondary endpoints at 6 and 12 months.

CONCLUSION

Our findings suggest that echo-guided implantation of an LV lead using STRSI does not improve the clinical or echocardiographic response compared with conventional implantation.

Ultrasonic biomechanics method for vortex and wall motion of left ventricle: a phantom and in vivo study

Background

The non-invasive quantitative evaluation of left ventricle (LV) function plays a critical role in clinical cardiology. This study proposes a novel ultrasonic biomechanics method by integrating both LV vortex and wall motion to fully assess and understand the LV structure and function. The purpose of this study was to validate the ultrasonic biomechanics method as a quantifiable approach to evaluate LV function.

Methods

Firstly, B-mode ultrasound images were acquired and processed, which were utilized to implement parameters for quantifying the LV vortex and wall motion respectively. Next, the parameters were compared in polyvinyl alcohol cryogen (PVA) phantoms with different degree of stiffness corresponding to different freezing and thawing cycles in vitro. Finally, the parameters were computed in vivo during one cardiac cycle to assess the LV function in normal and abnormal subjects in vivo.

Results

In vitro study, the velocity field of PVA phantom differed with stiffness (varied elasticity modulus). The peak of strain for wall motion decreases with the increase of elasticity modulus, and periodically changed values. Statistical analysis for parameters of vortex dynamics (energy dissipation index, DI; kinetic energy fluctuations, KEF; relative strength, RS; and vorticity, W) based on different elasticity (E) of phantom depicted the good viability of this algorithm. In vivo study, the results confirmed that subjects with LV dysfunction had lower vorticity and strain (S) compared to the normal group.

Conclusion

Ultrasonic biomechanics method can obtain the vortex and wall motion of left ventricle. The method may have potential clinical value in evaluation of LV dysfunction.

Myocardial involvement in Behçet's disease may be higher in patients with Neuro-Behçet's disease: a speckle tracking echocardiographic study

BACKGROUND

Behcet's disease (BD) may present with life threating complications including neurological and cardiovascular involvement. Neuro-Behcet's disease (NBD) is one of the most important causes of morbidity and mortality in patients with BD. The aim of the present study is to investigate whether patients with NBD are different than BD patients with other manifestations in terms of subclinical myocardial dysfunction.

METHODS

Forty patients with NBD (23 female, mean age: 42.4 ± 9.4 years), 40 patients with BD (9 female, mean age: 39.7 ± 9.0 years) and 40 controls (20 male, mean age: 41.8 ± 6.5 years) were consecutively included in the study. All subjects underwent a transthoracic echocardiography for evaluation of left ventricular (LV) and atrial (LA) functions with two-dimensional (2D) speckle tracking echocardiography (STE).

RESULTS

Baseline characteristics, clinical data, LV dimensions, systolic and diastolic functions were all in normal range among the groups. LV global longitudinal strain (LV-GLS) was significantly lower in patients with NBD and BD patients without neurologic involvement compared to controls. LA conduit strain was significantly lower in patients with NBD compared to controls. Patients with both parenchymal NBD and vascular NBD manifestations had significantly lower LV-GLS and LA conduit strain compared to controls. Linear regression analysis demonstrated that among cardiovascular risk factors only presence of NBD was the independent predictor of LV-GLS.

CONCLUSIONS

BD is associated with impaired LV and LA functions. LV-GLS and LA conduit strains of the patients with NBD were lower. NBD was an independent predictor of LV-GLS, suggesting a link between neurological manifestations and cardiac dysfunction in BD patients.

Role of Two-Dimensional Speckle-Tracking Echocardiography in Early Detection of Left Ventricular Dysfunction in Dogs

Simple Summary

Two-dimensional speckle-tracking echocardiography represents an advanced imaging technique that allows the analysis of global and regional myocardial function, cardiac rotation and synchronicity using deformation imaging. It has gained growing importance over the last decade, especially in human medicine as a method of evaluating myocardial function. This review aims to give an overview of the current understanding of this technique and its clinical applicability in the field of veterinary medicine with a focus on early detection of left ventricular dysfunction in dogs.

Abstract

Two-dimensional speckle-tracking echocardiography (2D–STE) is an advanced echocardiographic technique based on deformation imaging that allows comprehensive evaluation of the myocardial function. Clinical application of 2D–STE holds great potential for its ability to provide valuable information on both global and regional myocardial function and to quantify cardiac rotation and synchronicity, which are not readily possible with the conventional echocardiography. It has gained growing importance over the past decade, especially in human medicine, and its application includes assessment of myocardial function, detection of subclinical myocardial dysfunction and serving as a prognostic indicator. This review illustrates the fundamental concepts of deformation analysis and gives an overview of the current understanding and its clinical application of this technique in veterinary medicine, with a focus on early detection of left ventricular (LV) dysfunction in dogs.

Left ventricular dyssynchrony assessment using tissue synchronization imaging in acute myocardial infarction

Objectives:

To assess left ventricular (LV) dyssynchrony in patients with ST elevation myocardial infarction (STEMI).

Background:

Mechanical synchronization disorder leads to a decrease in LV ejection fraction (LVEF) and stroke volume, an abnormal distribution of wall tension, and increase in workload during cardiac contraction.

Methods:

We enrolled 56 participants, 36 with acute STEMI and 20 healthy controls. The automatically color-coded time to peak myocardial velocity was measured using a 6mm sample volume, manually positioned within the two-dimensional-tissue strain image of the 12 basal and middle LV segments.

Results:

A significant delay was found between the septal-lateral and septal-posterior walls in patients with STEMI compared to patients in the control group (36.36 vs. −6.0ms, P = 0.036; and 42.7 vs. 23.94ms, P = 0.042, respectively). Furthermore, all segment maximum differences and all segment standard deviation (SD; dyssynchrony index) were found to be significantly higher in the STEMI group (131.28 vs. 95.45ms, P = 0.013; and 44.47 vs. 26.45ms, P = 0.001, respectively). A significant delay between the septal-lateral walls and septal-posterior walls, all segment maximum difference, and all segment SD (dyssynchrony index) were found in patients with complicated STEMI (70.89 vs. 15.83ms, P = 0.038; 57.44 vs. 19.06ms, P = 0.040; 138.11 vs. 100.0ms, P = 0.035; and 45.44 vs. 32.50ms, P = 0.021, respectively). There was a significant negative correlation between tissue synchronization imaging parameters and LVEF, and a positive correlation with LV end systolic dimension.

Conclusion:

Patients with acute STEMI showed significant LV dyssynchrony, which was an independent predictor of inhospital complications.

Left ventricular dyssynchrony and post-systolic shortening in young bodybuilders using anabolic-androgenic steroids

Left ventricular (LV) remodeling, characterized by increased LV hypertrophy and depressed systolic and diastolic function, is observed in strength-trained athletes who use anabolic-androgenic steroids (AAS). Previous studies suggested a pathological remodeling with an increase in cardiac fibrosis in these athletes, which could promote intraventricular dyssynchrony. In this context, this study evaluated LV dyssynchrony in strength-trained athletes using AAS, hypothesizing that the use of AAS would lead to an increase in post-systolic shortening. Forty-four male subjects (aged 20-40 yr) were divided into three age-matched groups: strength-trained athletes using (users, n = 14) or not (nonusers, n = 15) AAS and healthy sedentary men (controls, n = 15). After completing a survey, each participant was assessed with two-dimensional (2D)-strain echocardiography. LV dyssynchrony was quantified using the standard deviation (SD) of the time to peak for longitudinal strain of the 18 LV-segments (from the apical 4, 3, and 2 chambers views), the longitudinal strain delay index (LSDI), and the segmental post-systolic index (PSI). Users showed mean AAS dosages of 564 ± 288 mg[Formula: see text]wk^-1 with a mean protocol duration of 12 ± 6 wk and a history of use of 4.7 ± 1.8 yr. They exhibited a greater LV mass index and depressed systolic and diastolic function when compared with both nonusers and controls. The decrease in LV strain in users was predominantly observed at the interventricular septum level (-16.9% ± 2.5% vs. -19.2% ± 1.8% and -19.0% ± 1.6% in users, nonusers, and controls, respectively, P < 0.01). Users showed higher SD than controls (43 ± 8 ms vs. 32 ± 5 ms, respectively, P < 0.01). The LSDI was significantly higher in users compared with both nonusers and controls (-23.4 ± 9.5 vs. -15.9 ± 9.3 and -9.8 ± 3.9, respectively, P < 0.01). PSI, calculated on the basal inferoseptal, basal anteroseptal, and basal inferolateral segments, were also greater in users compared with the two other groups. Our results reported an increase in LV dyssynchrony in young AAS users that brought new evidences of a pathologic cardiac remodeling in this specific population.NEW & NOTEWORTHY Illicit androgenic anabolic steroids (AAS) use is widespread, but data on LV dyssynchrony are lacking, although it could be increased by a higher prevalence of myocardial fibrosis reported in this population. In AAS users, the decrease in LV strain was predominantly observed in interventricular segments. All dyssynchrony indices were higher in AAS users and several segments exhibited post-systolic shortening. These results showed an association between AAS consumption, LV remodeling, and dyssynchrony.

Ensemble machine learning approach for screening of coronary heart disease based on echocardiography and risk factors

BACKGROUND

Extensive clinical evidence suggests that a preventive screening of coronary heart disease (CHD) at an earlier stage can greatly reduce the mortality rate. We use 64 two-dimensional speckle tracking echocardiography (2D-STE) features and seven clinical features to predict whether one has CHD.

METHODS

We develop a machine learning approach that integrates a number of popular classification methods together by model stacking, and generalize the traditional stacking method to a two-step stacking method to improve the diagnostic performance.

RESULTS

By borrowing strengths from multiple classification models through the proposed method, we improve the CHD classification accuracy from around 70-87.7% on the testing set. The sensitivity of the proposed method is 0.903 and the specificity is 0.843, with an AUC of 0.904, which is significantly higher than those of the individual classification models.

CONCLUSION

Our work lays a foundation for the deployment of speckle tracking echocardiography-based screening tools for coronary heart disease.

Deep insight into cardiac dysfunction in children and young adults with Wolff-Parkinson-White syndrome using speckle tracking imaging

Although ventricular pre-excitation via accessory pathways (APs) causes cardiac dysfunction in children and young adults with Wolff-Parkinson-White (WPW) syndrome, the underlying cardiac dysfunction mechanisms are unclear. This study aimed to characterize cardiac dysfunction and clarify sensitive cardiac dysfunction indicators in WPW syndrome patients classified by the APs location with a layer-specific strain analysis. Twenty-four patients with WPW syndrome with a mean age of 14.1 years (6.9-21.6 years) (11 cases: type A with a left-sided AP [WA group], 13 cases: type B with a right-sided AP [WB group]), and 37 age-matched normal controls (N group) were examined. We measured the left ventricle (LV), base-, mid-, and apical-level of circumferential strain (CS), and longitudinal strain (LS) using a layer-specific strain with speckle tracking imaging. Dyssynchrony was also measured based on the timing of the radial strain at each segment. Peak endomyocardial base- and mid-level of CS was lower in both the WA and WB groups compared to the N group. Peak mid-myocardial and epimyocardial base-level of CS and peak mid-myocardial mid-level of CS were lower only in the WB group compared to the N group. Peak LS in all three layers was lower only in the WB group compared to the N group. There was a significant difference between the patient and normal groups for the dyssynchrony index only at the base-level, and there was no significant difference between the groups for LV ejection fraction (EF). Layer-specific strain decreased in more sites in the WB group despite the normal EF value. Layer-specific strains are sensitive indicators for the detection of the early stages of cardiac dysfunction.

Ventricular and atrial functions assessed by speckle-tracking echocardiography in patients with human immunodeficiency virus

PURPOSE

Antiretroviral therapy (ART) has dramatically changed the clinical manifestation of human immunodeficiency virus (HIV) associated cardiomyopathy from severe left ventricular (LV) systolic dysfunction to a pattern of subclinical cardiac dysfunction. The aim of this study was to evaluate by speckle tracking echocardiography (STE) LV, right ventricular (RV), and biatrial functions in HIV-infected patients under different ART combinations.

METHODS

We consecutively included 128 HIV-infected patients (mean age 44.2 ± 10.1 years, 110 males) and 100 controls (mean age 42.1 ± 9.4 years, 83 males). Ventricular and atrial functions were assessed by both conventional and STE.

RESULTS

Although there was not any significant difference in conventional echocardiographic variables, HIV-infected patients had significantly lower LV global longitudinal strain (GLS), RV GLS, left atrial (LA) reservoir and conduit strain, and right atrial conduit strain. HIV patients receiving integrase strand transfer inhibitors and protease inhibitors (PI) had significantly lower LV GLS and LA conduit strain, while patients receiving non-nucleoside reverse transcriptase inhibitors and PI had significantly lower RV GLS than controls. CD4 count at the time of echocardiography was strongly correlated with LV GLS (r = .619, P < .001) and RV GLS (r = .606, P < .001).

CONCLUSION

Biventricular and atrial functions are subclinically impaired in HIV-infected patients. ART regimen may also affect myocardial functions.

A Strain-Based Staging Classification of Left Bundle Branch Block-Induced Cardiac Remodeling

OBJECTIVES

This study speculated that longitudinal strain curves in left bundle branch block (LBBB) could be shaped by the degree of LBBB-induced cardiac remodeling.

BACKGROUND

LBBB independently affects left ventricular (LV) structure and function, but large individual variability may exist in LBBB-induced adverse remodeling.

METHODS

Consecutive patients with LBBB with septal flash (LBBB-SF) underwent thorough echocardiographic assessment, including speckle tracking-based strain analysis. Four major septal longitudinal strain patterns (LBBB-1 through LBBB-4) were discerned and staged on the basis of: 1) correlation analysis with echocardiographic indexes of cardiac remodeling, including the extent of SF; 2) strain pattern analysis in cardiac resynchronization therapy (CRT) super-responders; and 3) strain pattern analysis in patients with acute procedural-induced LBBB.

RESULTS

The study enrolled 237 patients with LBBB-SF (mean age: 67 ± 13 years; 57% men). LBBB-1 was observed in 60 (26%), LBBB-2 in 118 (50%), LBBB-3 in 29 (12%), and LBBB-4 in 26 (11%) patients. Patients at higher LBBB stages had larger end-diastolic volumes, lower LV ejection fractions, longer QRS duration, increased mechanical dyssynchrony, and more prominent SF compared with less advanced stages (p < 0.001 for all). Among CRT super-responders (n = 30; mean age: 63 ± 10 years), an inverse transition from stages LBBB-3 and -4 (pre-implant) to stages LBBB-1 and -2 (pace-off, median follow-up of 66 months [interquartile range: 32 to 78 months]) was observed (p < 0.001). Patients with acute LBBB (n = 27; mean age: 83 ± 5.1 years) only presented with a stage LBBB-1 (72%) or -2 pattern (24%).

CONCLUSIONS

The proposed classification suggests a pathophysiological continuum of LBBB-induced LV remodeling and may be valuable to assess the attribution of LBBB to the extent of LV remodeling and dysfunction.

Cardiovascular Imaging Applications in Clinical Management of Patients Treated with Cardiac Resynchronization Therapy

Cardiovascular imaging techniques, including echocardiography, nuclear cardiology, multi-slice computed tomography, and cardiac magnetic resonance, have wide applications in cardiac resynchronization therapy (CRT). Our aim was to provide an update of cardiovascular imaging applications before, during, and after implantation of a CRT device. Before CRT implantation, cardiovascular imaging techniques may integrate current clinical and electrocardiographic selection criteria in the identification of patients who may most likely benefit from CRT. Assessment of myocardial viability by ultrasound, nuclear cardiology, or cardiac magnetic resonance may guide optimal left ventricular (LV) lead positioning and help to predict LV function improvement by CRT. During implantation, echocardiographic techniques may guide in the identification of the best site of LV pacing. After CRT implantation, cardiovascular imaging plays an important role in the assessment of CRT response, which can be defined according to LV reverse remodeling, function and dyssynchrony indices. Furthermore, imaging techniques may be used for CRT programming optimization during follow-up, especially in patients who turn out to be non-responders. However, in the clinical settings, the use of proposed functional indices for different imaging techniques is still debated, due to their suboptimal feasibility and reproducibility. Moreover, identifying CRT responders before implantation and turning non-responders into responders at follow-up remain challenging issues.

The effect of cardiac rehabilitation on blood pressure, and on left atrial and ventricular functions in hypertensive patients

PURPOSE

Hypertension is associated with left ventricular (LV) hypertrophy, impaired LV relaxation, and left atrial (LA) enlargement. Cardiac rehabilitation (CR) improves clinical outcomes in a broad spectrum of cardiac disease. The aim of our study was to determine the effect of CR on blood pressure (BP), and on LA and LV functions in hypertensive patients.

METHODS

Thirty consecutive hypertensive patients who would undergo CR program, and 38 hypertensive patients who refused to undergo CR program were included. All patients underwent ambulatory BP monitoring and transthoracic echocardiography, which were repeated after completion of the CR program, or 12 weeks later in the control group. LA and LV functions were assessed by both speckle tracking and 3-dimensional echocardiography. N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were assessed before and after CR.

RESULTS

Although initial ambulatory BP values and NT-proBNP levels were similar between the groups, daily, day-time, and night-time BP and NT-proBNP were significantly lower in the CR group after rehabilitation. LA reservoir strain and LV global longitudinal strain of the CR group significantly increased after CR while no significant increase was observed in controls.

CONCLUSION

CR improves LA and LV strain while lowering BP and should be encouraged in routine management of hypertensive patients.

The effect of smoking on atrial and ventricular functions in healthy subjects: A speckle tracking echocardiography study

PURPOSE

Smoking is a well-known risk factor for coronary artery diseases. It is also associated with nicotine-induced myocardial dysfunction. The aim of this study was to evaluate the right and left atrial and ventricular functions in apparently healthy smokers.

METHODS

We included consecutively 80 healthy smokers (56 males, mean age:35.5 ± 8.4 years) and 70 healthy nonsmokers (44 males, mean age:33.9 ± 9.5 years). None of the subjects had any additional cardiovascular risk factor other than smoking. The right and left atrial and ventricular functions were assessed by both conventional and speckle tracking echocardiography.

RESULTS

Although there was no significant difference in left ventricular ejection fraction, the smokers had significantly lower ventricular global longitudinal strain than controls (-19.9 ± 2.0% vs -21.2 ± 1.9%, P < .001 and -18.4 ± 2.1% vs -21.8 ± 2.2%, P < .001, respectively, for the left and right ventricle). Smokers had also lower atrial reservoir and conduit strains: 35.9 ± 11.1% vs 40.2 ± 11.2%, P = .022 and 16.7 ± 6.8% vs 19.4 ± 6.8%, P = .016, respectively, for the left atrium, and 33.0 ± 10.6% vs 37.6 ± 11.2%, P = .011 and 15.2 ± 5.6% vs 18.0 ± 6.3%, P = .004, respectively, for the right atrium).

CONCLUSION

Even in apparently healthy people with no other cardiovascular risk factors, smoking is associated with impaired atrial and ventricular functions.

The evaluation of ventricular functions by speckle tracking echocardiography in preeclamptic patients

Preeclampsia is a maternal disorder of pregnancy characterized by concomitant increase in preload and afterload with end organ dysfunction. The aim of our study is to evaluate left ventricular (LV) and right ventricular (RV) functions with speckle tracking echocardiography in preeclamptic patients. Fifty-five preeclamptic (mean age: 30.7 ± 5.9 years) and 35 healthy pregnant women (mean age: 28.8 ± 5.7 years) of the same race, similar age and gestational week were consecutively included. The diagnosis of preeclampsia was based on the criteria proposed by the American College of Obstetricians and Gynecologists. LV and RV functions were assessed by both conventional and speckle tracking echocardiography after the 30th gestational week and at the postpartum 6th months. The preeclamptic patients had significantly larger left atrium, thicker interventricular septum, higher systolic pulmonary artery pressure and mitral E/e' ratio compared to controls during pregnancy while LV ejection fraction was similar. Preeclamptic patients had significantly lower LV and RV global longitudinal strain (GLS) during pregnancy compared to controls (- 18.0 ± 2.6% vs. - 19.8 ± 2.1% p = 0.001 and - 26.7 ± 3.3% vs. 28.9 ± 3.3% p = 0.002, respectively). In the postpartum period, while LVGLS values of preeclamptic patients increased significantly (- 18.0 ± 2.6% vs. - 20.4 ± 2.4% p < 0.001) and became similar to those of controls at the sixth month, the RVGLS decreased significantly (- 26.7 ± 3.3% vs. - 25.8 ± 2.7% p = 0.003) making the difference in RVGLS between the preeclamptic patients and controls more prominent. Preeclampsia may impair LV and RV function. Long-term follow up with larger sample is needed to determine the clinical relevance of the observed changes in strain.

The effect of global longitudinal strain on ımpaired six-minute walk test performance in patients with sarcoidosis

Background:

Sarcoidosis is a multisystem and granulomatous disease associated with impaired functional capacity as a result of pulmonary and cardiac involvement. Factors adversely effecting functional capacity in patients with sarcoidosis have not been systematically assessed including myocardial strain imaging on echocardiography which enable to diagnose subclinical cardiac dysfunction. We aimed to evaluate the effect of left and right ventricular global longitudinal strain (GLS) on submaximal exercise capacity in patients with sarcoidosis who do not have clinically manifest cardiac involvement.

Methods:

Extracardiac biopsy proven 56 patients with sarcoidosis and 26 controls were included consecutively. Submaximal exercise capacity of the subjects was assessed with six-minute walk test (6 MWT). Pulmonary function tests and standard transthoracic and two-dimensional speckle tracking echocardiography were performed to the all subjects. Linear regression analysis was performed to find independent predictors of 6 MWT.

Results:

Fifty-six patients (18% male) with a mean age of 52.5 ± 10.7 years were included. Patients with sarcoidosis had low 6 MWT performance and higher New York Heart Association classes and NT-proBNP levels. There were no significant differences between controls and patients with sarcoidosis in parameters of pulmonary function test. Biventricular GLS levels and biatrial reservoir and conduit function values were lower and systolic pulmonary artery pressure (SPAP) was significantly higher in patients with sarcoidosis as compared with controls. Older age and higher SPAP were found as independent predictors of poor 6 MWT performance.

Conclusion:

Although biventricular GLS levels were lower in the patients with sarcoidosis, only age and SPAP elevations were independent predictors of the submaximal exercise capacity. (Sarcoidosis Vasc Diffuse Lung Dis 2020; 37 (1): 63-73)

The relationship between global longitudinal strain and pulmonary function tests in patients with scleroderma and normal ejection fraction and pulmonary artery pressure: a case-control study

This study examined the relationship between global longitudinal strain (GLS) and pulmonary function tests (PFT) in patients with systemic sclerosis (SS) and normal ejection fraction (EF) and pulmonary artery pressure (PAP) and healthy controls. Sixty patients in two groups underwent extensive screening, including echocardiography, physical examination, the modified Rodnan Skin Score, and pulmonary function tests. Pulmonary interstitial disease was diagnosed by the pulmonary function test and by CT scan in case of indication. GLS score was computed as the mean peak systolic strain for 17 segments. The mean GLS score was - 18.36 ± 2.1 in the case group and - 20.66 ± 1.6 in the control group (P value < 0.001). GLS scores had a significant inverse relationship with the forced expiratory volume in one second (FEV1) to forced vital capacity (FVC) ratio (P value = 0.049) and both FEV and FVC in patients younger than 35 years old (P = 0.046 and 0.049, respectively). GLS scores had no significant relationship with time elapsed since the onset of skin manifestations, and Raynaud phenomenon, Rodnan score, EF, systolic PAP, or the six-minute walk test results. The patients' six-minute walk test had a significant positive relationship with FVC and right ventricular end diastolic diameter (P value = 0.018 and 0.047, respectively). According to our findings, GLS is significantly lower in patients with SS (with normal EF & PAP) than in healthy individuals. It is also related with certain pulmonary function indices including FEV1/FVC. The reduction in GLS is associated with reduced pulmonary function strength.

Two-dimensional speckle tracking echocardiography in goats: repeatability, variability, and validation of the technique using an exercise test and an experimentally induced acute ischemic cardiomyopathy

Background

Two-dimensional speckle tracking (2DST) technique has been validated in numerous animal species, but neither studies of repeatability nor measurements after exercise or in animals with cardiac disease have been reported in goats. Goats are an attractive candidate for animal models in human cardiology because they are easy to handle and have a body and heart size comparable to that of humans. Therefore, the aim of this study was to validate this technique in goats for further clinical and experimental applications in this species.

Results

This study was divided into several steps. First, a standardized echocardiographic protocol was performed and 5 cineloops of a right parasternal short-axis view at papillary muscles level were recorded three times at one-day intervals in ten healthy adult unsedated Saanen goats to test repeatability and variability of 2DST measurements. Then, the same measurements were performed immediately before and after a standardized exercise on treadmill in seven of the goats, and at 24 h after induction of an experimental ischemic cardiomyopathy in five of the goats, to test the reliability of the technique to assess physiological and pathological changes. Average and regional measurements of radial and circumferential strain and strain rate, radial displacement, rotation and rotation rate were obtained. Comparisons were performed using two-way ANOVA (p < 0.05). Caprine 2DST average measurements have demonstrated a good repeatability with a low to moderate variability for all measurements except for the diastolic peaks of the circumferential strain rate, radial strain rate and rotation rate. Segmental 2DST measurements were less repeatable than average measurements. Time effect of two-way ANOVA was significant for anteroseptal segment diastolic peaks measurements, rotation and rotation rate measurements. Overall variability of segmental measurements was moderate or high. Segmental and average peak values obtained after exercise and after myocardial ischemia were significantly different than curves obtained at baseline.

Conclusions

The results of this study are consistent with those previously described in other animal species and humans. 2DST echocardiography is a valid technique to evaluate physiological and pathological changes in myocardial function in goats, despite the technical limitations observed in this species.

Biventricular pacemaker therapy improves exercise capacity in patients with non-obstructive hypertrophic cardiomyopathy via augmented diastolic filling on exercise

AIMS

Treatment options for patients with non-obstructive hypertrophic cardiomyopathy (HCM) are limited. We sought to determine whether biventricular (BiV) pacing improves exercise capacity in HCM patients, and whether this is via augmented diastolic filling.

METHODS AND RESULTS

Thirty-one patients with symptomatic non-obstructive HCM were enrolled. Following device implantation, patients underwent detailed assessment of exercise diastolic filling using radionuclide ventriculography in BiV and sham pacing modes. Patients then entered an 8-month crossover study of BiV and sham pacing in random order, to assess the effect on exercise capacity [peak oxygen consumption (VO₂ )]. Patients were grouped on pre-specified analysis according to whether left ventricular end-diastolic volume increased (+LVEDV) or was unchanged/decreased (-LVEDV) with exercise at baseline. Twenty-nine patients (20 male, mean age 55 years) completed the study. There were 14 +LVEDV patients and 15 -LVEDV patients. Baseline peak VO₂ was lower in -LVEDV patients vs. +LVEDV patients (16.2 ± 0.9 vs. 19.9 ± 1.1 mL/kg/min, P = 0.04). BiV pacing significantly increased exercise ΔLVEDV (P = 0.004) and Δstroke volume (P = 0.008) in -LVEDV patients, but not in +LVEDV patients. Left ventricular ejection fraction and end-systolic elastance did not increase with BiV pacing in either group. This translated into significantly greater improvements in exercise capacity (peak VO₂  + 1.4 mL/kg/min, P = 0.03) and quality of life scores (P = 0.02) in -LVEDV patients during the crossover study. There was no effect on left ventricular mechanical dyssynchrony in either group.

CONCLUSION

Symptomatic patients with non-obstructive HCM may benefit from BiV pacing via augmentation of diastolic filling on exercise rather than contractile improvement. This may be due to relief of diastolic ventricular interaction.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT00504647.

Evaluation of left and right ventricle by two-dimensional speckle tracking echocardiography in systemic sclerosis patients without overt cardiac disease

BACKGROUND/OBJECTIVE

The aim was to evaluate the left and right ventricular functions concurrently by two-dimensional speckle tracking echocardiography (STE) in systemic sclerosis (SSc) patients without overt cardiac disease.

METHODS

A total of 47 patients with SSc and 36 age- and sex-matched controls were evaluated cross-sectionally. Two-dimensional STE was used to assess the longitudinal peak systolic strains (PSS) of both ventricles including apical long-axis (APLAX), apical four-chamber (4-CH), apical two-chamber (2-CH), and global longitudinal measurements. Any association of metabolic, cardiac, and inflammatory biomarkers with PSS was investigated.

RESULTS

The longitudinal PSS of the left ventricle [APLAX, 4-CH, 2-CH and global] were significantly lower in SSc patients than controls (- 18.2 ± 3.2 vs - 19.8 ± 2.7% p = 0.02; - 17.8 ± 3.5 vs. - 20.3 ± 3.3% p = 0.001; - 18.6 ± 3.1 vs. - 21.8 ± 3% p < 0.001; - 17.5 ± 5.7 vs. - 20.6 ± 2.7% p = 0.003, respectively). No difference was found between the groups for right ventricular strains. The longitudinal PSS-4CH correlated positively with CRP and ESR (r = 0.349, p = 0.016; r = 0.356, p = 0.014, respectively) and negatively with serum Galectin-3 (r = - 0.362, p = 0.012). Global longitudinal PSS-left ventricle (LV) correlated positively with CRP and homocysteine (r = 0.297, p = 0.043; r = 0.313, p = 0.041, respectively) and negatively with serum Galectin-3 (r = -0.314, p = 0.041). After multivariable adjustment, CRP remained the only predictor of longitudinal PSS-4CH (95% CI 0.35, 0.70, p = 0.028) and global longitudinal PSS of left ventricle (95% CI 0.004, 0.22, p = 0.043).

CONCLUSIONS

Biventricular evaluation of patients with SSc by two dimensional STE revealed reduced left ventricular longitudinal strains, despite preserved right ventricular strain, and no diastolic dysfunction. In SSc without overt cardiac disease, global cardiac assessment with 2DSTE is a promising method which seems to contribute to the detection of patients without clinical findings.

KEY POINTS

• Two dimensional STE revealed reduced left ventricular longitudinal strains, despite preserved right ventricular strain in SSc patients without overt cardiac disease. • CRP was the predictor of decreased longitudinal strains. • Cardiac assessment in SSc should be made globally.

Role of cardiovascular imaging in cardiac resynchronization therapy: a literature review

: Cardiac resynchronization therapy (CRT) is an established treatment in patients with symptomatic drug-refractory heart failure and broad QRS complex on the surface ECG. Despite the presence of either mechanical dyssynchrony or viable myocardium at the site where delivering left ventricular pacing being necessary conditions for a successful CRT, their direct assessment by techniques of cardiovascular imaging, though feasible, is not recommended in clinical practice by the current guidelines. Indeed, even though there is growing body of data providing evidence of the additional value of an image-based approach as compared with routine approach in improving response to CRT, these results should be confirmed in prospective and large multicentre trials before their impact on CRT guidelines is considered.

Speckle tracking echocardiography analyses of myocardial contraction efficiency predict response for cardiac resynchronization therapy

BACKGROUND

In patients with left ventricular (LV) dysssynchrony, contraction that doesn't fall into ejection period (LVEj) results in a waste of energy due to inappropriate contraction timing, which was now widely treated by cardiac resynchronization therapy(CRT). Myocardial Contraction Efficiency was defined as the ratio of Efficient Contraction Time (ECTR) and amplitude of efficient contraction (ECR) during LVEj against that in the entire cardiac cycle. This study prospectively investigated whether efficiency indexes could predict CRT outcome.

METHODS

Our prospective pilot study including 70 CRT candidates, parameters of myocardial contraction timing and contractility were measured by speckle tracking echocardiography (STE) and efficiency indexes were calculated accordingly at baseline and at 6-month follow-up. Primary outcome events were predefined as death or HF hospitalization, and secondary outcome events were defined as all-cause death during the follow-up. 16-segement Standard deviation of time to onset strain (TTO-16SD) and time to peak strain (TTP-16SD) were included as the dyssynchrony indexes.

RESULTS

According to LV end systolic volume (LVESV) and LV eject fraction(LVEF) values at 6-month follow-up, subjects were classified into responder and non-responder groups, ECR (OR 0.87, 95%CI 0.78-0.97, P < 0.05) and maximum longitudinal strain (MLS) (OR 2.22, 95%CI 1.36-3.61, P < 0.01) were the two independent predictors for CRT response, Both TTO-16SD and TTP-16SD failed to predict outcome. Patients with poorer myocardial contraction efficiency and better contractility are more likely to benefit from CRT.

CONCLUSIONS

STE can evaluate left ventricular contraction efficiency and contractility to predict CRT response. When analyzing myocardial strain by STE, contraction during LVEj should be highlighted.

Current role of echocardiography in cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is an established treatment for patients with heart failure and left ventricular systolic dysfunction. Patients are usually assessed by echocardiography, which provides a number of anatomical and functional information used for cardiac dyssynchrony assessment, prognostic stratification, identification of the optimal site of pacing in the left ventricle, optimization of the CRT device, and patient follow-up. Compared to other cardiac imaging techniques, echocardiography has the advantage to be non-invasive, repeatable, and safe, without exposure to ionizing radiation or nefrotoxic contrast. In this article, we review current evidence about the role of echocardiography before, during, and after the implantation of a CRT device.

Mechanical dyssynchrony in patients with heart failure and reduced ejection fraction: how to measure?

PURPOSE OF REVIEW

This article summarizes the most recent imaging techniques to assess left ventricular mechanical dyssynchrony and discusses their value to predict response to cardiac resynchronization therapy (CRT) together with assessment of myocardial scar and cardiac venous anatomy.

RECENT FINDINGS

Left ventricular mechanical dyssynchrony has been associated with prognosis of heart failure patients and has been shown to influence the efficacy of CRT. Although current guidelines do not recommend the assessment of left ventricular mechanical dyssynchrony to select heart failure patients for CRT, technological advances in echocardiography, cardiac magnetic resonance, nuclear imaging and computed tomography have provided powerful tools to characterize left ventricular mechanical dyssynchrony and predict response to CRT. Most important, these imaging techniques permit integration of additional information that is relevant for the efficacy of CRT, such as the extent and location of myocardial scar and the anatomy of the coronary sinus and tributaries where the left ventricular pacing lead may be positioned.

SUMMARY

Left ventricular mechanical dyssynchrony is an important parameter to select heart failure patients who are candidates for CRT. The integration of this parameter together with extent and location of myocardial scar and cardiac venous anatomy is a key to optimize the efficacy of CRT.

The impact of right ventricular function assessed by 2-dimensional speckle tracking echocardiography on early mortality in patients with inferior myocardial infarction

BACKGROUND

Right ventricular (RV) involvement in inferior myocardial infarction (MI) increases in-hospital morbidity and mortality.

HYPOTHESIS

RV systolic dysfunction assessed by 2-dimensional speckle tracking echocardiography (STE) might be a predictor of early mortality in patients with acute inferior MI.

METHODS

Eighty-one consecutive patients with acute inferior MI (mean age, 60.8 ± 12.7 years; 18 females) were included. RV myocardial involvement was defined as an elevation >1 mm in V₁ or V₄ R within 12 hours of symptom onset. RV function was assessed by STE. Patients were followed for 30 days for all-cause mortality.

RESULTS

Thirty-eight patients had RV myocardial involvement, and they had significantly lower tricuspid annular plane systolic excursion (TAPSE), tricuspid annular systolic velocity (RVS), and left ventricular (LV) and RV global longitudinal strain (GLS). Nine patients (11%) died within 30 days. The mean age of mortality group was higher with more female frequency. They had significantly higher pro-BNP, hs-troponin T, and creatinine levels, but lower hemoglobin levels. TIMI 3 flow was significantly less achieved in mortality group. RV myocardial involvement was more frequent in the mortality group, and they had significantly lower TAPSE, RVS, and LV and RV GLS. Multivariate analysis revealed that age and RV GLS were independent predictors of early mortality. RV GLS ≤ -14% predicted early mortality in patients with acute inferior MI with a sensitivity of 88.9% and a specificity of 62.5% (AUC: 0.817, P = 0.002).

CONCLUSIONS

RV GLS may be useful in predicting early mortality in patients with acute inferior MI.