Apical View Research Articles

Relative interventricular septal brightness for subtype diagnosis of cardiac amyloidosis: pixel brightness analysis using echocardiographic images

Abstract Background In the subtypes of cardiac amyloidosis (CA), transthyretin-related (ATTR) CA has been reported to exhibit a higher prevalence of microcalcifications in the interventricular septum (IVS) compared to other subtypes. Whether microcalcifications in the IVS can stratify CA subtypes remains unclear. Methods A total of 442 patients with CA: 76 light chain/ amyloid A (AL/AA) type; 255 wild type ATTR (ATTRwt) and 48 variant ATTR (ATTRv) and 19 patients with endomyocardial biopsy-confirmed hypertensive heart disease (HHD) were subjected to echocardiographic pixel brightness quantification of the IVS using open-access image analysis software. The IVS Brightness Index (IVSBI) was defined as the ratio of the average pixel brightness in the IVS to that in the left ventricular (LV) wall opposite the IVS (see figure 1). Results The IVSBI from apical 4-chamber view was higher in both the ATTRwt group (median 1.40, IQR 1.22 to 1.67) and the ATTRv group (1.59, 1.32 to 2.00) compared to the HHD group (1.20, 1.02 to 1.37) and the AL/AA group (1.25, 1.11 to 1.46), respectively (P <0.001, see figure 2). In the 273 CA patients undergoing myocardial technetium-99m-pyrophosphate scintigraphy, patients with positive results (1.41, 1.24 to 1.70) exhibited a higher IVSBI compared to those with negative (1.19, 1.09 to 1.46) (P = 0.006). In Cox proportional hazards analysis, age, gender and LV ejection fraction adjusted hazard ratio for the all-cause death of IVSBI (0.5 increase) was 2.0 (95% CI 1.2 to 3.5, P = 0.012) among ATTRwt patients (n=157). Conclusions An IVSBI obtained from the apical 4-chamber view could prove valuable in differentiating ATTR subtypes in CA, potentially revealing subtle septal calcifications. A prognostic value may be derived from the elevation of IVSBI in ATTRwt patients.figure 1figure 2

Inter-Vendor differences in speckle tracking strain - A ten year follow-up on the Strain Standardization Task Force Inter-Vendor Comparison Study

Abstract Background Global longitudinal strain (GLS) derived from two-dimensional speckle-tracking echocardiography is feasible and accurate. Nonetheless, in 2013, the Inter-Vendor Comparison Study showed significant differences of measurement results among vendors. In order to make tracking-based strain imaging a clinically accepted and useful parameter, it is of outmost importance to have interchangeable and accurate measurement results from all vendors. Purpose To investigate if the efforts of the EACVI/ASE/Industry Task Force to Standardize Deformation Imaging have led to a reduction of inter-vendor differences during the past ten years. Methods In an unique setting, in one single room, 372 echocardiographic examinations were performed in sixty-two subjects (50 male, age 56.1 ± 16.98) with a wide range of left ventricular (LV) function (ejection fraction from 30% to 64%) using ultrasound systems from six manufacturers. Each subject was scanned consecutively on all machines by the same assigned experienced sonographer. For each subject two image sets of LV apical views were acquired in order to assess reproducibility in a true test-retest setting. We assessed mean GLS (GLSAV) as average peak systolic global strain from the three apical views on five vendor-specific and five vendor-independent software solutions. We measured endocardial and mid-/full-wall GLS. Since there is no gold standard method to measure GLS, we compared GLSAV of each vendor to the average of the GLS values only from vendors that provide tracking software solutions (SWS) for clinical use. Results For both endocardial (Figure 1) and mid-/full-wall (Figure 2) GLS measurements from clinical SWS were comparable and within a very narrow range (mean GLS of vendors 17.25 ± 0.3% and 15.36 ± 0.3% respectively). The maximum absolute difference between all SWS was 4.1% and 4.9% strain units for endocardial and mid-/full-wall GLS respectively. GLSAV of each software versus the mean of clinical SWS showed significant correlation for most of the companies (r² >0.8, p<0.001). Test-retest variability of GLS measurements expressed as relative mean error was good and lower than for LV ejection fraction (6.3% on average for mean GLS and 7% for LV ejection fraction, p>0.05). Conclusions Our data show a substantial inter-vendor bias in GLS measurements. Nevertheless, in contrast to the situation ten years ago, companies that provide tracking software solutions for clinical use provide now very similar GLS values. In addition, most companies do now allow mid-/full-wall tracking. Our data indicate that the efforts of the strain standardization task force have been fruitful. A continuing effort is needed until all software providers adhere to the task force consensus recommendations.Figure 1Figure 2

Usefulness of left ventricular mechanical dyssynchrony for predicting atrial fibrillation and adverse outcomes following first atrial fibrillation event

Abstract Background Left ventricular mechanical dyssynchrony (LVMD) has shown to predict many cardiovascular outcomes including ventricular arrhythmias. Our hypothesis is that LVMD can reveal early atrial dysfunction. Purpose The aim of this study was to investigate whether LVMD can be used to predict atrial fibrillation (AF) and adverse outcomes following first AF event in individuals from the general population. Methods A total of 3785 individuals (mean age 55±17 years, 57% women) from the general population free of AF, heart failure (HF) and prior stroke had an echocardiographic examination performed including two-dimensional speckle tracking echocardiography. LVMD was calculated as the standard deviation of the regional time-to-peak strain from the three apical views. The primary endpoint was AF, and the secondary endpoint was complicated AF as assessed by the occurrence of either stroke or HF after the diagnosis of AF. Results During a median follow-up of 5 years (interquartile range, 4.4-6.2 years), 142 (4%) individuals were diagnosed with AF, and of these 22 (15%) individuals developed HF or stroke. LVMD was a univariable predictor of AF (per 10ms increase: HR 1.03; 95% CI (1.02-1.05), p<0.001, Figure). The association remained significant even after multivariable adjustment for age, sex, body mass index, diabetes, hypertension, heart rate, previous ischaemic heart disease, systolic blood pressure, diastolic blood pressure, smoking, left ventricular ejection fraction, global longitudinal strain, left atrial volume index (LAVI), and E/e’ (per 10ms increase: HR 1.02; 95% CI (1.00-1.04), p=0.042). LVMD also predicted complicated AF, and the association remained significant even after multivariable adjustment (per 10ms increase: HR 1.05; 95% CI (1.01-1.09), p=0.026). Furthermore, LVMD provided incremental prognostic information over the LAVI with regard to predicting AF (Harrell’s C-statistics 0.66 vs. 0.70, p=0.012). Conclusion In a low-risk general population, LVMD provides prognostic information on the risk of AF. Additionally, LVMD can identify individuals with complicated AF defined as occurrence of either stroke or HF following the diagnosis of incident AF. Furthermore, LVMD provides incremental prognostic information over the LAVI in predicting AF.

The importance of heart rate on left ventricular global longitudinal strain in echocardiography: novel insights facilitated by automated deep learning methods

Abstract Background Heart rate (HR) is assumed to influence echocardiographic measurements. Consequently, HR needs to be considered for accurate assessment of cardiac function. Despite left ventricular global longitudinal strain (LV GLS) being recognised as a valuable measure of cardiac function, its normal reference ranges remain confined to patients within a limited range of resting HR. So far, time-consuming manual analyses and high measurement variability have precluded comprehensive assessment of the interplay between HR and LV GLS. Using fully automated GLS measurements provided by novel deep learning (DL) methods, it is now possible to evaluate changes in LV GLS across a wide range of HR. Purpose To improve echocardiographic assessments across a wide range of HR intervals, we aimed to study the influence of controlled HR variations on LV GLS using programmable pacemakers and fully automated DL measurements. Methods Participants with sinus node dysfunction and implanted programmable pacemakers were enrolled. Echocardiographic acquisitions were obtained at baseline HR and during stepwise increments by 10 beats/min, targeting a range from 50 to 140 beats/min. Recordings of cine-loops including 10 cardiac cycles were obtained for the four-chamber, two-chamber, and apical long axis view. LV GLS was measured for all cycles using a fully automated DL method developed by our group, and presented as mean of the three standard apical views for all patients at each HR level. A linear mixed model was used for construction of an overall trendline based on the estimated fixed effects across all 50 patients, stating patient number as the random effect. The correlation between HR and LV GLS was evaluated by a likelihood ratio test. Results Fifty patients were included, 52% females, mean age 68 years (27 to 88 years). All patients had preserved atrioventricular conduction. Resting HR ranged from 50 to 87 beats/min (mean 64 beats/min). At baseline echocardiographic acquisition, most participants were within normal ranges for LV volumes, systolic and diastolic function. A total of about 13,000 cardiac cycles were automatically analysed by the DL method. The overall trend demonstrated a linear relation between increasing HR and decreasing absolute LV GLS (Figure 1). Across HR increments from 50 to 140 beats/min, there was a 32% (22%–42%) reduction in absolute LV GLS, declining from -17.1% to -11.7%. The strong correlation between changes in HR and LV GLS was further supported by a highly significant likelihood ratio test (p-value <0.001). Conclusions There was a reduction of absolute LV GLS with increasing HR. These findings emphasize the importance of integrating HR considerations into clinical echocardiography practice. Moreover, the results highlight that DL methods can unlock substantially richer insights from individual patient data, offering a new pathway towards more personalized and precise cardiac diagnostics.Figure 1

Serial changes in left and right ventricular global longitudinal strain in symptomatic obstructive hypertrophic cardiomyopathy treated with mavacamten: insights from VALOR-HCM trial

Abstract Background In severely symptomatic patients with obstructive hypertrophic cardiomyopathy (HCM), the VALOR-HCM phase 3 randomized, double-blind, placebo-controlled clinical trial demonstrated that mavacamten, reduces the need for septal reduction therapy with sustained improvement in left ventricular outflow tract gradients and symptoms. As a cardiac myosin inhibitor, mavacamten’s mechanism of action reduces myocardial hypercontractility. Global longitudinal strain (GLS), a measure of regional myocardial function, is a more sensitive marker of systolic function and can complement left ventricular ejection fraction (LVEF). Objective We sought to assess serial changes in LV and right ventricular (RV)-GLS in patients enrolled in the VALOR-HCM study. Methods VALOR-HCM included 112 symptomatic obstructive HCM patients (mean 60 years, 51% male, LVEF 68%). Patients assigned to mavacamten at baseline continued the drug for 56 weeks (n=56) and those assigned to placebo crossed over to mavacamten (n=52) from week 16-56 (40-week exposure). LV and RV-GLS assessment was performed according to the current American and European guideline recommendations using a vendor-neutral post processing software. Non-foreshortened apical (4, 3 and 2-chamber) views were used to obtain peak value of LV-GLS. For RV-GLS, RV focused 4-chamber view was used to calculate RV 4-chamber and free wall strain. A more negative strain value is favorable. Results Serial changes in LVEF, average LV-GLS, and RV-GLS (4-chamber and free wall) from baseline to week 56 are shown in the Figure. Despite preserved LVEF at baseline, average baseline LV-GLS was abnormal. There were significant and continued improvements in LV-GLS in the total group from baseline to week 56. 12 patients had transient reduction in LVEF (<50%) requiring temporary drug interruption (permanent discontinuation in 3). The LV-GLS in this subgroup was worse at baseline compared to the total study population, with no significant worsening from baseline through week 56. In the overall population, excluding these 12 patients, LV-GLS demonstrated an improvement sustained through week 56. Both free wall and 4-chamber RV-GLS were abnormal at baseline and remained unchanged from baseline to week 56. Conclusions In the VALOR-HCM trial, despite hypercontractile LVEF at baseline, average baseline LV-GLS was worse than normal reference values. Treatment with mavacamten resulted in an improvement in LV-GLS from baseline through Week 56 (with no significant worsening of LV-GLS in the subgroup who experienced any reduction in LVEF <50%), suggesting a favorable long-term impact on regional LV systolic function due to the reduction of cardiac hypercontractility. Additionally, there was no significant detrimental impact on RV systolic function on serial GLS assessment.Serial changes in LV and RV GLS in VALOR

Serial changes in left atrial strain in symptomatic obstructive hypertrophic cardiomyopathy treated with mavacamten: insights from VALOR-HCM trial

Abstract Background In severely symptomatic patients with obstructive hypertrophic cardiomyopathy (HCM), the VALOR-HCM phase 3 randomized, double-blind, placebo-controlled clinical trial demonstrated that mavacamten, a cardiac myosin inhibitor, reduces the eligibility for septal reduction therapy with sustained improvement in left ventricular (LV) outflow tract gradients and symptoms. Mavacamten also resulted in favorable cardiac remodeling, including improvement in left atrial volume index (LAVI), LV diastolic function, and biomarkers (NT-proBNP and troponin T). However, the impact of mavacamten on LA function is not known. Objective We sought to assess serial changes in LA strain measures in patients enrolled in the VALOR-HCM trial. Methods VALOR-HCM included 112 symptomatic obstructive HCM patients (mean age 60 years, 51% male). Patients assigned to mavacamten at baseline (n=56) continued therapy for 56 weeks and those assigned to placebo crossed over to mavacamten (n=52) from week 16-56 (40-week exposure). Echocardiographic LA strain assessment was performed according to the current American and European guideline recommendations, using a vendor-neutral post processing software. For assessment of LA strain components (reservoir, conduit, and contraction), the non-foreshortened apical 4-chamber view was utilized. The zero reference was set at end-diastole. Results Serial changes in LAVI and all components of mean LA strain from baseline to week 56 are shown in the Figure. At baseline, LAVI and all mean LA strain values were worse than reported normal mean thresholds. There was a continued and significant improvement in all 3 LA strain values, from baseline to week 56, along with a significant reduction in LAVI. Improvement in LAVI was seen earlier than improvements in LA strain. There was a significant inverse correlation between change in mean LAVI and LA reservoir strain from baseline to week 56 (r= -0.42, p<0.001). Conclusions In the VALOR-HCM trial, average LAVI and baseline LA strain values were significantly worse than reported normal thresholds. Treatment with mavacamten resulted in an improvement in LAVI and LA strain values from baseline through week 56 suggesting a sustained favorable impact on cardiac remodeling. The advantageous cardiac remodeling associated with long-term treatment with mavacamten may in turn have a favorable impact on the observed high burden of atrial tachyarrhythmias in HCM.Serial changes in LA strain in VALOR-HCM

Dynamic changes of excessive trabeculation in dilated cardiomyopathy: a longitudinal cardiovascular magnetic resonance study

Abstract Background A portion of dilated cardiomyopathy (DCM) patients present with left ventricular (LV) excessive trabeculation at diagnosis. It remains unknown if the extent of trabeculation would be reduced after guideline-directed medical therapy (GDMT). Purpose To investigate the dynamic change of excessive trabeculation after GDMT in patients with DCM, and its relationship with that in LV structure and function. Methods A group of DCM patients with baseline and follow-up cardiovascular magnetic resonance (CMR) examination after 1-2 years of GDMT were enrolled. Trabeculation was assessed by Petersen method as measuring the thickness of the most prominent non-compacted (NC) layer and the corresponding compacted (C) segment at the apical long-axis view at end-diastole. Excessive trabeculation was defined as the NC/C ratio > 2.3, and a regression was reached if it decreased to ≤ 2.3. Major adverse cardiovascular events (MACE) consisted of cardiovascular death, heart transplantation, and heart failure readmission. Results Among 218 DCM patients (45 ± 14 years, 67.4% male), 58 (26.6%) met the excessive trabeculation criteria at baseline. Despite a similar LV ejection fraction (LVEF), patients with excessive trabeculation had a higher LV end-diastolic dimension (73.3 ± 9.0 vs. 70.5 ± 8.0mm) and native T1 (1325.3 ± 71.2 vs. 1305.5 ± 65.9mm) (both p<0.05) with a trend of more late gadolinium enhancement (51.7% vs. 39.4% of patients). After 15 months of GDMT, patients with excessive trabeculation (n=58) showed a decreased NC layer (12.7 ± 3.4 vs. 11.3 ± 3.0 mm) and NC/C ratio (3.1 ± 0.9 vs. 2.7 ± 0.9) (both p < 0.05), 25.9% of whom showed a regression of trabeculation. Patients with the regression had a lower NC/C ratio (1.8 ± 0.4 vs. 3.0 ± 0.8, p < 0.001) and LV end-diastolic volume index (LVEDVi) (121.5 ± 40.5 ml/m2 vs. 165.9 ± 67.8ml/m2, p=0.004) compared with those without. The change of (△) NC/C ratio was associated with that of LVEDVi (r = 0.323), and LVEF as well (r = -0.254) (both p < 0.001). Excessive trabeculation at baseline did not differentiate patients with a higher risk of MACE by Kaplan-Meier survival curve (p= 0.208), but its persistent presence at follow-up did (p= 0.004). However, when put △NC/C ratio, △LVEDVi, △LVEF and In NT-proBNP into multivariate cox regression model, only the △LVEDVi (HR, 0.963; 95% CI: 0.942, 0.985; P = 0.001) and In NT-proBNP (HR, 2.016; 95% CI: 1.288, 3.157; P = 0.002) were independent predictors of MACE. Conclusions Regression of excessive trabeculation occurred after GDMT in DCM patients that was related somewhat to LV reverse remodeling and not an independent predictor of MACE. It may also indicate the interconnection between LV remodeling and trabeculation.

Predictive value of total atrial conduction time for developing cerebrovascular stroke in patients with sinus rhythm and normal left ventricular systolic function, a case-control study

Abstract Background Stroke is the second leading cause of death worldwide. Recently, atrial cardiopathy has become recognized as a substantial risk factor for cerebrovascular stroke. Greater LA size is linked to stroke in AF patients, but few data linking LA size to stroke in population with sinus rhythm. Purpose To investigate the value of total atrial conduction time (TACT) measured non-invasively by assessing PA-TDI duration as a predictor of stroke in patients who initially presented with sinus rhythm and have normal LV systolic function. Methods In our case-control study, we included 156 patients with acute ischemic stroke and 50 control subjects all presented in sinus rhythm and normal LV systolic function. All participants underwent echocardiography. The bi-plane modified Simpson's approach was used to determine the LV-EF. The left atrial (LA) diameter was measured also left atrial volume index (LAVI) was assessed. The PA-TDI interval was used to estimate the TACT. In the apical four-chamber view, the pulsed-wave tissue Doppler sample was positioned on the lateral and septal walls of the LA above the mitral annulus. The time between the onset of the P wave (lead II) and the peak of the A' wave was called the PA-TDI interval. Also, speckle tracking indices of LA strain were measured. Results LA volume index was larger in the stroke group (39.24±4 versus 33.6±2.8, p: 0.01), PA-TDI duration showed statistical highly significant difference between both groups (165.94±21.695 versus 99.4±22.960, p: <0.001). There were significantly impaired LAS parameters in the stroke group (LA reservoir, contraction & conduit strain, 22.7%, -6.6% & -16.1% versus 40%, -12%, and − 27% in the control group with P < 0.000). ROC curve showed the best cutoff point for LA volume index is >42.2 ml/m2 for prediction of stroke with area under the curve (AUC): 0.7, p value is 0.005. ROC curve showed the best cutoff point for PA-TDI is >155.5 ms. with AUC: 0.9, 90% sensitivity, 91% specificity, p value: <0.001. ROC curve showed that LA reservoir strain and LA stiffness can independently predict stroke at cut-off values of 30% & 24.5% respectively, P < 0.001. Multivariate logistic regression analysis showed that hypertension, LA volume index, LA stiffness and PA-TDI duration are independent predictors of stroke (p: < 0.05, < 0.05, < 0.01 and < 0.001 respectively). Conclusions The assessment of electromechanical asynchrony by measuring the PA-TDI duration may help to predict patients at risk for stroke. It is easy to measure without the need for special software like speckle tracking indices. We also advise patients who exceed the cutoff points of LA volume index and PA-TDI duration to receive antithrombotic therapy for better stroke prevention. Also we recommend adding PA-TDI to CHA2DS2-VASC-HSF score to assess stroke risk in patients with sinus rhythm and paroxysmal AF during their sinus rhythm intervals.

LA reservoir strain predicts elevated left atrial pressure in patients with Veno-Arterial (VA) extracorporeal membrane oxygenator (ECMO) support for cardiogenic shock

Abstract Background Veno-arterial (VA) extracorporeal membrane oxygenator (ECMO) is not a left ventricular (LV) support system as it increases aortic pressure and LV afterload due to retrograde blood flow in the aorta. This can lead to complications such as increased LV volume (LV distention), increased LV and left atrial (LA) pressures, and pulmonary edema. We sought to investigate the correlation between LA strain and invasive LA pressure (LAP) in patients with ECMO support for cardiogenic shock undergoing atrial septostomy with stenting. Methods and Results A total of 24 consecutive patients (52±20 years; 83% were male) undergoing atrial septostomy with stenting while being on ECMO support for cardiogenic shock for left heart decompression were analyzed. LAP was measured immediately after transeptal puncture and before deployment of interatrial septal stent. A comprehensive echocardiogram was performed in all patients prior to atrial septostomy. Median time difference between echocardiogram and LAP measurement was 3.5 (0.5-20) hours. LA strain analysis was performed using the TomTec Arena 2D-cardiac performance analysis (CPA) software. LA reservoir strain was measured at peak systole during the reservoir phase in a single apical 4-chamber view. Intraclass correlation coefficients between 2 different investigators were excellent (All> 0.95). Median LA reservoir strain and LAP were 3.2 (0.5-1) % and 23 (8-53) mmHg, respectively. LA reservoir strain significantly correlated with LAP (r=0.53, p=0.034). LA reservoir strain of < 1.5% can effectively predict markedly elevated LAP (LA> 30 mmHg) (OR =9.9, p =0.0016). Conclusions LA reservoir strain significantly correlated with invasive LAP. With the advent of strain imaging software, LA reservoir strain is a feasible, reproducible, noninvasive, and straightforward method to predict the need for left heart decompression and/or to guide optimal afterload management in patients with VA-ECMO for cardiogenic shock. Further a prospective simultaneous echocardiographic and invasive LAP study is needed.

Normal reference values of left atrioventricular coupling index on two-dimensional echocardiography

Abstract Background From a physiological background, there is close relationship between left atrial (LA) and left ventricular (LV) expressed as coupling. The assessment of LA/LV coupling may reflect LV dysfunction and differentiate between normal and abnormal LV function. Aim of study The study is designed to sample normal subjects to provide the normal reference values of LA/LV coupling index (LACI) according to age and sex using 2-dimensional echocardiography (2DE). Methods 550 healthy subjects (51.9±17.8 years, 56% males) were included with good 2DE image quality enabled measurement of end-diastolic volumes of both LA and LV. LACI was defined as the ratio between LA to LV end-diastolic volumes. Results An off-line analysis of apical 4-chamber and 2-chamber views to obtain the 2DE measurements was performed within short time (1.5± 0.3 min). Measurement of LACI was obtained in all individuals. Subjects were divided into 3 age groups (G I: 18-40 years, G II: 41-65 years, and GIII: >65 years). As shown in table 1, the normal LACI values in the whole population was 0.17±0.08 with significantly higher in females (0.178±0.09) than males (0.15±0.06); P<0.02. The LACI values tends to be higher in females than males in the subdivided 3 age groups but not statistically significant. In both sexes, increasing age was associated with significant reduction of the mean LVEDV (P<0.0001), significant increase of the mean LAEDV (P= 0.004), and significant increase of LACI (P< 0.0001); especially considering the differences between the youngest and oldest age groups. Conclusions Measurement of LACI is feasible and easily obtainable using 2DE. Age and sex should be considered when defining normal reference values for LACI. The standardization of normal LACI values will help the future studies to assess the changes of these normal values in various cardiac abnormalities for prognostic risk stratification.

Verification of intra- and inter-atrial conduction during Bachmann's bundle pacing using longitudinal bi-atrial strain

Abstract Introduction Although atrial septal pacing has been reported to reduce atrial fibrillation (AF) burden, there is less evidence regarding its effect on the prevention of permanent AF and the improvement of long-term clinical outcomes. However, Bachmann's bundle pacing (BBp), which features P-wave morphology similar to sinus rhythm and shortened P-wave duration (PWD), was reported to significantly reduce permanent AF recurrences and occurrences compared with right atrial appendage pacing (RAAp) and non-specific right septal pacing. Purpose Possible mechanisms for AF suppression with BBp are that fast inter-atrial conduction through BB decreases global atrial activation time and the dispersion of the overall atrial refractoriness, and it prevents the decrease in left ventricular filling and increase in left atrial pressure associated with delayed left atrial contraction. Intra-and inter-atrial conduction during BBp was evaluated using longitudinal bi-atrial strain. Methods In patients with successful BBp implantation defined by electrocardiographic criteria using SelectSecure pacing lead and C315 delivery catheter (Medtronic, Inc), both left atrium (LA) and right atrium (RA) global longitudinal strain (GLS) in simultaneous phases were measured using Philips Ultrasound Workspace 2D Strain in apical 4-chamber view during atrial pacing to assess intra- and inter-atrial conduction delay. The atrial GLS were measured semi-automatically, and the strain rate was analyzed in the three segments of septal wall, lateral wall, and roof and their average. The negative peak of strain rate during atrial systole was the starting point of atrial contraction, and time to peak (TTP) was measured. The difference in TTP between septal and lateral walls in each atrium was measured as intra-atrial conduction delay and the difference in average TTP between LA and RA as inter-atrial conduction delay. Results Ten patients who underwent successful BBp were enrolled (Sick sinus syndrome: 3, advanced atrioventricular block: 2, complete atrioventricular block: 5). At implantation, bipolar atrial electrogram amplitude was 2.03±0.93 mV, atrial lead impedance was 632.7±157.6 Ω, and atrial pacing threshold was 0.7±0.2 V at 0.4 ms. The PWD during sinus rhythm on the 12-lead ECG was 132.8±10.6 ms, while during BBp it was 108.0±11.9 ms, which was significantly shorter in the BBp group (p<0.001). The intra-atrial conduction delay in RA and LA was 10.9 ± 12.1 ms and 12.1 ± 17.3 ms, respectively, and the inter-atrial conduction delay was 6.6 ± 8.6 ms. On the other hand, for the 10 RAAp and 10 sinus rhythm patients as control groups, the inter-atrial conduction delay was 29.7±13.8 ms and 8.5±9.5 ms, respectively. BBp had significantly less inter-atrial conduction delay than RAAp (p=0.005) and was comparable to sinus rhythm (p=0.719). Conclusion Longitudinal bi-atrial strain suggested that BBp significantly reduced inter-atrial delay and it might be effective in AF suppression.Longitudinal bi-atrial strain

Prognostic value of echocardiographic parameters in predicting major adverse cardiac events one year following st-segment elevation myocardial infarction

Abstract Approximately 50% of patients who survive an ST-segment elevation myocardial infarction (STEMI) experience irreversible damage to the heart muscle, which increases long-term risk of developing heart failure. Moreover, cardiovascular mortality constitutes half of all deaths. This research aimed to determine the best combination of patient data collected during a one-year follow-up period to enhance the accuracy of outcome predictions for patients with STEMI. Methods In this study, 246 patients who experienced STEMI and older than 18 were prospectively monitored. All participants received primary percutaneous coronary intervention treatment. The study's primary outcomes, observed over the year following hospital discharge, included cardiovascular death, recurrent myocardial infarction, newly diagnosed heart failure, and arrhythmias or conduction issues. Of the patients, 18% of patients reached the primary outcomes. Two-dimensional transthoracic echocardiography was conducted 3-5 days after the initial event to assess left ventricular global longitudinal strain (GLS) using 2D speckle-tracking echocardiography on the apical four-chamber, two-chamber, and long-axis views. Left ventricular mechanical dispersion was calculated as the standard deviation of the time from the Q/R wave onset to peak GLS across 17 segments of the left ventricle. Results The findings revealed that the overall GLS was -10.70 (-12.61 to -8.40), but in patients who met the study's primary outcomes, GLS was significantly lower at -7.83 (-8.70 to -6.90), compared to -12.02 (-13.11 to -10.17) in those who did not, with a significant difference (p=0.00001). Mechanical dispersion was 40.24±26.56 in the entire cohort but significantly higher at 65.62±22.57 in the outcome group compared to 25.79±14.81 in the non-outcome group (p=0.00001). The ejection fraction averaged 48.97±7.69% across all patients, 47.22±7.16% in those with outcomes, and 49.92±7.84% in those without, with a statistically significant difference (p=0.039). Cox regression analysis identified key predictors of major adverse cardiac events (MACE) within one year after STEMI, including global longitudinal strain (p=0.0006), left atrium volume index (p=0.0448), left ventricular end-diastolic diameter (p=0.045), and mechanical dispersion (p<0.0001). A multivariate logistic regression analysis demonstrated that a combination of GLS, left ventricular end-systolic volume (LVESV), mechanical dispersion, and ejection fraction could predict 1-year MACE with high accuracy (χ2 = 85.18; p<0.0001, AUC=0.961 [0.903-0.989]). In conclusion, this study identifies crucial metrics, such as global longitudinal strain, left ventricular end-systolic volume, mechanical dispersion, and ejection fraction, as predictive factors for MACE one year following STEMI. This predictive model is straightforward, reproducible, and can be easily implemented in cardiology practice.

Higher product of right ventricle to left ventricle diameter ratio and septal wall thickness is associated with increased risk of cardiovascular death in patients post TAVI

Abstract Background Right ventricular (RV) dilatation is a significant predictor for mortality in various cardiovascular diseases. Hypertrophy is common in patients undergoing transcatheter aortic valve implantation (TAVI). We tested the hypothesis that the product of right ventricle to left ventricle diameter (RV/LV) ratio and septal wall thickness (SWT) might be a determinant of cardiovascular death in TAVI patients. Methods This retrospective study enrolled 1123 patients undergoing TAVI in our department between 2009 and 2021 (mean age 81.4±5.6 year, male 51.2%). We assessed standard echocardiographic measures prior to the TAVI procedure. End-diastolic basal biventricular dimensions were measured from a standard apical 4-chamber view, and the ratio of RV dimension (RVD) to LV dimension (LVD) was calculated as the RV/LV ratio. We tested the prognostic performance of the product of RV/LV ratio and septal wall thickness (RV/LV ratio*SWT). The primary endpoint was cardiovascular (CV) death up to 2 years after TAVI. Results CV mortality was 11.8% (132/1123) at 2 years after TAVI. SWT was similar between the groups with and without CV death (11.9±1.9 vs. 11.6±1.8 mm, P=0.188). However, the RV/LV ratio (0.84±0.15 vs. 0.80±0.13, P=0.002) and RV/LV ratio*SWT (10.0±2.7 vs. 9.3±3.1 mm, P=0.005) were notably higher in the CV-death group compared to the no CV-death group. Higher RV/LV ratio*SWT remained independently associated with elevated 2-year CV mortality after TAVI (HR=1.09, 95% CI 1.01-1.17, P=0.024), while the RV/LV ratio was no longer significantly linked with CV mortality (HR=2.83, 95% CI 0.87-9.19, P=0.082) after adjusting for potential confounding factors including age, sex, and atrial fibrillation. RV/LV ratio*SWT >12.7 mm was associated with a twofold increased risk of 2-year CV mortality compared to patients with RV/LV ratio*SWT ≤12.7 mm (2-year mortality 14.4% vs. 6.0%, P<0.001; HR=2.04, 95% CI 1.25-3.32, P=0.004), regardless of age, sex, and atrial fibrillation. Conclusions Combined assessment of biventricular remodelling and left ventricular hypertrophy by calculating RV/LV ratio*SWT is of clinical importance for risk stratification of cardiovascular death among TAVI patients.

Left ventricular myocardial work predicts clinical course in patients with heart failure with mildly reduced ejection fraction

Abstract Heart failure with mildly reduced ejection fraction (HFmrEF) often represents a movable patients subset that changes its HF category by increasing or reducing EF. Course prediction is challenging due to insufficient evidence to date. We studied multiple newly established parameters in order to find predictors of clinical course of HFmrEF. Methods 135 patients (61 women) 62±5 years with HFmrEF NYHA II-III on GDMT were enrolled. Longitudinal (GLS), circumferential (GCS) and radial strain (GRS), peak LV twist (LVTR) were measured by speckle tracking from apical and short axis views. Left ventricular (LV) global myocardial work (GW) index (GWI) was obtained from pressure-strain loops derived from LV GLS and supine systemic blood pressure measured right before the image acquisition. Then constructive GW (GCW) as the sum of positive work due to myocardial shortening during systole and negative work due to lengthening during isovolumic relaxation, wasted GW (GWW) as energy loss by myocardial lengthening in systole and shortening in isovolumic relaxation and GW efficiency (GWE) as the percentage ratio of constructive work to the sum of constructive work and wasted work were obtained by dedicated software. All parameters were analyzed offline by one experienced specialist. Patients were followed up for 1 year. Results 38 (28%) patients improved EF to the value ≥50%, 31 (23%) reduced EF to ≤40%. Patients with improved EF had significantly higher absolute values of GLS (17.3±2.2 vs 15.8±3.1%, p<0.03), GCS (18.9±2.6 vs 16.1±1.9%, p<0.02), GRS (42.5±7.2% vs 31.3±4.7%, p<0.02), LVT (6.2±2.5° vs 5.3±2.3°, p<0.03), GCW (2253±121 vs 1872±132 mmHg%, p<0.001) and lower GWW (108±7 vs 128±12 mmHg%) compared with patients with later reduced EF. Multivariate analysis showed that lower GCW was associated with EF reduction (HR 0.982, 95% CI 0.969–0.996, p = 0.012). GCW was the powerful predictor of CV events (AUC 0.94) with cut off value of 1495 mmHg% that had 98% sensitivity and 86% specificity. Conclusion LV GCW predicts EF changes in patients with HFmrEF.

Improving time-efficiency and accuracy in echocardiography: real-time automated measurements of left ventricular global longitudinal strain using deep learning

Abstract Background Accurate quantification of left ventricular (LV) systolic function is fundamental in echocardiography. LV Global Longitudinal Strain (GLS) offers advantages over LV ejection fraction, being more sensitive, reproducible and offering better prognostic value. However, existing semi-automatic methods are time-consuming and heavily operator-dependent. Additionally, poor image quality and foreshortening decrease accuracy and reproducibility of GLS. As a result, these challenges lead to suboptimal efficiency and underutilization of GLS quantification in clinical practice. Purpose Our objective was to develop a deep learning (DL) application for real-time automated measurements of GLS, capable of providing tracking quality and foreshortening feedback during scanning. Subsequently, we aimed to validate the novel method in a prospective cohort study. Methods Deep learning networks were trained to identify apical views, identify timing of end-systole and end-diastole, conduct cardiac segmentation, estimate myocardial motion, assess LV length in each view for foreshortening detection, and present real-time visualization of tracking quality and GLS values for three cardiac cycles to the operator for review (Figure 1). The DL method was validated in a prospective cohort of 40 patients included regardless of image quality. Agreement with manual measurements obtained using semi-automatic software (EchoPAC version 204, GE HealthCare, Horten, Norway) was evaluated. Bland-Altman statistics and Pearson's correlation coefficient were used to evaluate agreement and correlation. Results Feasibility for real-time DL measurements of GLS was 98%, with one patient excluded due to poor image quality. There was good agreement (Bias 0.7%, LoA: -1.6 to 3.1%, figure 2) and excellent correlation (Pearson’s correlation coefficient of 0.93, p<0.001) between the real-time DL application and manual reference measurements for GLS. Using the DL application during scanning resulted in a 58% (95% CI 56%-61%) reduction in time required for scanning and post-processing to obtain GLS values, compared to using the semi-automatic method. Average time consumption was 2 minutes and 16 seconds for the DL method and 5 minutes and 27 seconds for the reference method. Conclusion Using deep learning, real-time fully automated measurement of GLS during scanning is feasible, time-saving, and provides good agreement with reference methods. Real-time measurements also offer the potential to reduce operator-related variability by integrating tools to provide image and tracking quality feedback to the user, ultimately benefiting patients.Application user interfaceAgreement between DL and reference

Assessment of Biventricular Systolic and Diastolic Function Using Conventional and Strain Echocardiography in Children with Sickle Cell Disease Surviving 1-year After Hematopoietic Stem Cell Transplant.

Hematopoietic stem cell transplant (HSCT) is a potentially curative therapy for children with sickle cell disease (SCD). The effects of HSCT on ventricular function are not well characterized in children with SCD. Echocardiograms from children with SCD who underwent HSCT between 2007 and 2017 were retrospectively analyzed before and 1-year after HSCT. Left ventricular (LV) volumes, mass, and ejection fraction were calculated by the 5/6 area*length method. LV end-diastolic and systolic dimensions, septal, and posterior wall thickness, and fractional shortening were measured by M-mode. Mitral and tricuspid inflow Dopplers (E and A waves) as well as mitral, tricuspid, and septal tissue Dopplers (E', A') were assessed. E/A, E'/A' and E/E' ratios were calculated. Biventricular strain imaging was performed using speckle-tracking echocardiography. Peak global systolic longitudinal and circumferential LV strain, and global longitudinal right ventricular strain, as well as early and late diastolic strain rate, were measured on LV apical 4-chamber, LV short-axis mid-papillary, and RV apical views, respectively. Forty-seven children (9.7 ± 5.5years, 60% male) met inclusion criteria. Pre-HSCT, subjects had mild LV dilation with normal LV systolic function by conventional measure of ejection fraction and fractional shortening. There was a significant reduction in LV volume, mass, and ejection fraction after HSCT, but measurements remained within normal range. LV longitudinal and circumferential strain were normal pre-HSCT and showed no significant change post-HSCT. RV strain decreased after HSCT, but the absolute change was small, and mean values were normal both pre- and post-HSCT. Conventional measures of diastolic function were all normal pre-HSCT. Post-HSCT there was a reduction in select parameters, but all parameters remained within normal range. Early and late diastolic strain rate parameters showed no significant change from pre- to post-HSCT. At one-year after HSCT in children with SCD conventional measures of systolic and diastolic function are within normal limits. Except for a small decrease in RV systolic strain with values remaining within normal limits, systolic strain and diastolic strain rate values did not significantly change 1-year after HSCT.

Triphasic diastolic transmitral and intraventricular blood flows and their relationship with LV diastolic dysfunction according to echocardiography

An acceleration of blood flow in the diastasis phase with the formation of the so-called L-wave may be found in some patients. The transmitral blood flow is transformed into a triphasic in the presence of L-wave.Objective: to assess the frequency of L-wave presence and to evaluate the relationship between the presence of L-wave in Doppler imaging of left ventricular blood flow, transmitral blood flow at the level of the mitral valve leaflets, and modern criteria for assessing left ventricular diastolic function.Material and methods. The study included 105 patients (age 62.21 ± 11.97 (29–91) years, 61 men) with sinus rhythm. From a total of examined patients, 30 were conditionally healthy, 64 patients suffered from coronary heart disease, and 11 suffered from arterial hypertension. Pulsed-wave Doppler ultrasound of transmitral flow was performed in the apical 4-chamber view with the sample volume located at the level of the ends of the mitral valve leaflets, as well as at the level of the basal and middle segments of the left ventricle. The distinct positive wave on the spectrogram during the diastasis phase with a speed exceeding 20 cm/s was considered an additional L-wave, and such blood flow in diastole was considered triphasic.Results. Triphasic transmitral blood flow was found in 9 patients (8.5%), and triphasic intraventricular blood flow in another 30 patients (28.5%). Patients with triphasic transmitral blood flow were older, with a greater left atrial volume index, and LV diastolic dysfunction was more often detected compared to patients with triphasic intraventricular blood flow (66.7% compared to 23.3%, p = 0.042).Conclusion. Triphasic transmitral blood flow is revealing significantly less frequently than triphasic intraventricular blood flow (8.5% compared to 28.5%, p < 0.001). Triphasic transmitral blood flow is more often observed in patients with left ventricular diastolic dysfunction.

Comparison of 6 handheld ultrasound devices by point-of-care ultrasound experts: a cross-sectional study

BackgroundPoint-of-care ultrasound (POCUS) has emerged as an essential bedside tool for clinicians, but lack of access to ultrasound equipment has been a top barrier to POCUS use. Recently, several handheld ultrasound devices (“handhelds”) have become available, and clinicians are seeking data to guide purchasing decisions. Few comparative studies of different handhelds have been done. We conducted a cross-sectional study comparing 6 handhelds readily available in the United States (Butterfly iQ + ™ by Butterfly Network Inc.; Clarius™ by Clarius Mobile Health; Kosmos™ by EchoNous; TE Air™ by Mindray; Vscan Air™ SL and CL by General Electric; and Lumify™ by Philips Healthcare). A multi-specialty group of physician POCUS experts (n = 35) acquired three standard ultrasound views (abdominal right upper quadrant, cardiac apical 4-chamber, and superficial neck and lung views) in random order on the same standardized patients and rated the image quality. Afterward, a final survey of the overall ease of use, image quality, and satisfaction of each handheld was completed.ResultsThirty-five POCUS experts specializing in internal medicine/hospital medicine, critical care, emergency medicine, and nephrology acquired and rated right upper quadrant, apical 4-chamber, and superficial neck and lung views with 6 different handhelds. For image quality, the highest-rated handhelds were Vscan Air™ for the right upper quadrant view, Mindray TE Air™ for the cardiac apical 4-chamber view, and Lumify™ for superficial views of the neck and lung. Overall satisfaction with image quality was highest with Vscan Air™, Lumify™, and Mindray, while overall satisfaction with ease of use was highest with Vscan Air™. The 5 most desirable characteristics of handhelds were image quality, ease of use, portability, probe size, and battery life. Ultimately, all 6 handhelds had notable advantages and disadvantages, with no single device having all desired qualities or features.ConclusionsThe overall satisfaction with image quality was rated highest with Vscan Air™, Lumify™, and Mindray TE Air™when acquiring right upper quadrant, apical 4-chamber, and superficial neck and lung views. No single handheld was perceived to be superior in image quality for all views. Vscan Air™ was rated highest for overall ease of use and was the most preferred handheld for purchase by POCUS experts.

Hypertension and Left Ventricular Strain in Pediatric Chronic Kidney Disease.

Left ventricular global longitudinal strain (LV GLS) on echocardiography is a sensitive yet clinically significant marker of myocardial dysfunction. Reduced LV GLS is prevalent in adults with chronic kidney disease and hypertension and is associated with adverse cardiovascular outcomes. It may be a biomarker of chronic kidney disease-associated myocardial dysfunction in children, but data are limited. Our objective was to describe LV GLS in the CKiD study (Chronic Kidney Disease in Children) and to examine the association between blood pressure (BP) and reduced LV GLS. A single apical 4-chamber view was used to estimate LV GLS. Our main analyses examined the association of clinic BP with the absolute value of LV GLS and LV GLS dichotomized at 16. Sensitivity analyses using 24-hour ambulatory BP monitoring data were also performed. Generalized estimating equations were used to account for within-person correlation and to estimate robust SEs for 95% CIs. Covariates in adjusted models included: age, sex, race, estimated glomerular filtration rate, urine protein, hemoglobin, left ventricular hypertrophy, and the use of renin-angiotensin system inhibitors. LV GLS was measured in 962 person-visits. A total of 77 assessments had an LV GLS <16. In adjusted models, both clinic systolic BP (odds ratio, 1.02 [95% CI, 1.01-1.03]) and diastolic BP (odds ratio, 1.02 [95% CI, 1.00-1.03]) percentiles were associated with LV GLS <16. Having awake or nighttime diastolic BP hypertension on ambulatory BP monitoring was significantly associated with a lower absolute value of LV GLS. Office systolic and diastolic hypertension was associated with diminished LV GLS. Only diastolic hypertension detected on ambulatory BP monitoring was associated with lower LV GLS.

Correlation between corrected carotid flow time and left ventricular outflow tract velocity-time integral using a novel technique.

Transthoracic echocardiography (TTE) is widely used for assessing patients in the intensive care unit, with cardiac output measurement being crucial for hemodynamic monitoring. This is achieved by measuring the velocity-time integral (VTI) of the left ventricular outflow tract (LVOT), which serves as a surrogate of stroke volume. However, conducting TTE in the critical care setting presents several challenges. Our primary objective was to investigate the relationship between carotid corrected flow time (cCFT) and LVOT VTI. Additionally, we aimed to determine the threshold cCFT value that reliably predicts a normal LVOT VTI. This proof-of-concept study involves a post-hoc analysis from a diagnostic accuracy investigation conducted in a medical-surgical intensive care unit. We included patients admitted to the ICU from December 2021 to January 2022. We used a phased array transducer to measure the cCFT at the left supraclavicular fossa and the LVOT VTI in an apical 5-chamber view. We included 22 patients. The Spearman coefficient between LVOT VTI and cCFT was 0.82 (p < 0.0001). The area under the ROC curve for cCFT to predict LVOT VTI equal to or greater than 17 cm was 0.871 (95% CI 0.660-0.974). A cCFT exceeding 283 ms predicted LVOT VTI equal to or greater than 17 cm with a sensitivity of 93.3% (95% CI 68.1% to 99.8%) and specificity of 85.7% (95% CI 42.1% to 99.6%). The cCFT, measured using a novel technique with a phased array transducer, shows a strong correlation with LVOT VTI. Additionally, cCFT predicts a normal LVOT VTI with good sensitivity and specificity in critically ill patients. Larger studies are warranted to validate these findings.