LVOT VTI Research Articles

Revisiting the Normal Ranges of Aortic Valve Area in 2D Echocardiography and Its Association With Age, Sex, and Anthropometric Characteristics.

Defining normative aortic echocardiographic values in each geographical district is crucial as aortic valve area (AVA) may vary across races, genders, and ages. Notably, variations in normal values can have implications for clinical decision-making, and available data on the Middle East population is also scarce. We sought to establish normal ranges for aortic valve echocardiographic parameters in the Iranian population and assess the effect of age, gender, weight, height, BMI, BSA, and blood pressure on them. Our data were provided from the web-based echocardiographic data registry of Imam Khomeini Hospital Complex (IKHC). A total of 3251 healthy subjects older than 18 years old without any valvular stenosis were included in our study. AVA's normal range was estimated at 1.92-4.52 and 1.67-3.80 cm2 in men and women, respectively. The annulus, AVA, AV VTI, and LVOT VTI were significantly larger in males, and this association remained significant after indexing AVA for weight, height, BMI, and BSA. Also, smaller AVA was associated with lower height, weight, BMI, and BSA in both men and women. Obese and hypertensive subjects had significantly larger AVA and annulus diameters. Our study provided region-specific normal reference values for AV echocardiographic parameters and compared them across genders, ages, BMI, and blood pressure groups in the Iranian population.

Association between left ventricular outflow tract velocity time integral, ejection fraction, clinical characteristics, and mortality in an undifferentiated cohort of hospitalised patients

Abstract Background Left ventricular ejection fraction (LVEF) is commonly used to predict mortality in heart failure patients. However, LVEF is dependent on factors including preload, afterload, contractility, heart rate and measurement accuracy. Recently, left ventricular outflow tract velocity time integral (LVOT VTI) has been shown to confer additional prognostic value in both patients with advanced heart failure and patients hospitalised with heart failure with preserved ejection fraction. Purpose We evaluated the association between LVOT VTI, LVEF, clinical characteristics and mortality in an undifferentiated cohort of hospitalised patients. Methods All hospitalised patients who underwent echocardiogram between January – March 2021 were identified from a single-centre tertiary hospital database. Baseline characteristics, echocardiographic parameters, biomarkers, and mortality at 24 months were collected. Patients were categorised into LVOT VTI tertiles (> 19cm, 13.1 – 18.9cm, < 13cm) and LVEF tertiles (> 50%, 40-50%, < 40%) for analysis; p<0.05 was considered significant. Results Altogether, 653 patients comprising 370 (57%) with LVOT VTI > 19cm, 228 (35%) with 13.1 - 18.9cm, and 55 (8%) with < 13cm were included. There were 183 (28%) deaths. Mortality was associated with increased age (75.6 + 13.5 years vs 64.9 + 16.8 years, p<.0001), high-risk echocardiographic features including increased left atrial size (45.4 + 22.7ml/m² vs 35.8 + 14.9 ml/m², p<.001), E/e’ (14.8 + 8.7 vs 10.4 + 4.3, p<.001), reduced LVEF (51.7 + 15% vs 55.9 + 12%, p=.005) and tricuspid annular plane systolic excursion (TAPSE; 2 + 0.5cm vs 2.1 + 0.7cm, p=.001), and biomarkers including haemoglobin (99 + 45g/L vs 117 + 46g/L, p<.001), albumin 28 + 10g/L vs 32 + 10g/L, p<.001), elevated N-terminal pro brain natriuretic peptide (5126 + 5997ng/L vs 2035 + 3569ng/L, p<.0001), troponin (191 + 1301ng/L vs 102 + 306ng/L, p=.008) and creatinine (152 + 165µmol vs 86 + 99µmol, p<.001) levels on admission. Whilst there was no significant difference between LVOT VTI and mortality (z=-1.73, p=0.083) there was a significant positive relationship between LVOT VTI and LVEF (r [651] =0.49, p<.001). Further, there was a significant association between death and both LVEF tertiles (X2 [2, N=653] = 19.63, p<.0001), and LVOT VTI tertiles (X2 [2, N=653] = 9.05, p=.011). However, small subset analyses revealed similar mortality rates for the lowest LVEF LVOT VTI tertile (46%, n=55), lowest LVEF tertile (46%, n=87), and when combined (50%, n=32). Conclusion In an undifferentiated cohort of hospitalised patients, reduced LVOT VTI and LVEF are both associated with increased mortality. However, LVOT VTI does not appear to outperform LVEF in being associated with mortality.

Acute echocardiographic assessment of patients with ST-elevation myocardial infarction in detecting clinically hidden hemodynamic deterioration

Abstract Background Transthoracic echocardiography (TTE) offers an immediate non-invasive assessment of cardiac morphology and function that can be performed bedside. Acute TTE in the catheterization laboratory (cath.lab.) may be helpful to identify markers of subsequent development of cardiogenic shock (CS) in patients with ST-elevation myocardial infarction (STEMI) in addition to the previously validated ORBI risk score. This relationship has not been investigated thoroughly previously. Purpose To investigate the association between acute TTE estimates of left ventricular (LV) function prior to primary percutaneous coronary intervention (pPCI) in STEMI patients and pro-B-type natriuretic peptide (proBNP) as a proxy associated with of CS development. Method From September 2023 all non-CS STEMI patients at one tertiary heart center underwent acute bedside TTE in the cath.lab. and ORBI risk score assessing the risk of CS development aiming for inclusion of 500 patients. The 5 minutes TTE-protocol consisted of LV ejection fraction (EF), LV outflow tract velocity time integral (LVOT VTI), mitral inflow (E and E/A), mitral deceleration time, and mitral annular early diastolic velocity é lateral. The primary endpoint was proBNP measured 24 hours (h) after pPCI (12-36h) stratified in quartiles (Q4 vs. Q1-3). The correlation between proBNP and TTE measurements and proBNP and ORBI risk score was examined using univariate linear regression models. Results Until now 153 STEMI patients (mean age 64 years, 25% female) were studied. Anterior STEMI was present in 36%, and median time from cath. lab. arrival to first wire over the culprit lesion was 28 minutes (IQR 24; 37). Patients with high proBNP level (Q4 vs. Q1-3) had significantly higher heart rate (median 84 bpm vs. 72 bpm) and Killip Class>1 (16% vs. 0%) at admission, but similar lactate levels (1.8mM vs. 1.5mM), systolic blood pressure (130 mmHg vs. 137 mmHg), and out-of-hospital cardiac arrest (11% vs. 12%). Patients with high proBNP levels (Q4 vs. Q1-3) had significantly lower LVEF (35% vs. 50%), higher E/é lateral (median 11.4 vs. 7.9), and higher ORBI risk score (median 8 vs. 4). LVEF, LVOT VTI, E/é lateral, and ORBI risk score were significantly associated with proBNP (Figure 1). Two patients developed CS after the pPCI; one with high proBNP level Q4, and one deceased prior to proBNP measurement. Conclusion Acute TTE is an easy tool for assessment of the acute hemodynamic status in STEMI patients bedside in the cath.lab., and it can be without delaying time to revascularization. LVEF, LVOT VTI, E/é lateral, and ORBI were all parameters associated with increased levels of the hemodynamic biomarker proBNP, and may together with the ORBI risk score improve the assessment and risk stratification of STEMI-patients at risk of CS-development.Figure 1.

Echocardiographic parameters for weaning from Extracorporeal Membrane Oxygenation - the role of longitudinal function and cardiac time intervals.

Limited data exist on echocardiographic predictors of weaning from veno-arterial extracorporeal membrane oxygenation (V-A ECMO). We aimed to test the performance of different echocardiographic indices to predict weaning from V-A ECMO. and free survival after weaning. Observational study including patients with cardiogenic shock submitted to V-AECMO. Echocardiography was performed after V-AECMO placement and daily during the weaning trial to assess cardiac recovery. Echocardiography data after V-A ECMO implantation and during the last weaning-trial before V-A ECMO removal were analyzed. Besides traditional parameters, total isovolumic time (t-IVT, a left ventricular performance index) and mitral annular plane systolic excursion (MAPSE) were also tested.76 patients were included. A greater ventricular velocity-time integral (LVOT VTI) at baseline was associated with a 5-fold increase in weaning success (p < 0.001) as MAPSE lateral >6.15 mm (p 0.001) did. TAPSE and S' at tricuspid annulus showed an analogous association. During the weaning trial t-IVT, LVEF, MAPSE, LVOT VTI and TAPSE all improved significantly (p <0.001 for all). At regression analysis t-IVT <14.4second/minute (<0.001), LVOT VTI >12.3cm (p <0.001), MAPSE >8.9mm (p < 0.001), TAPSE> 16mm (<0.001) and E/e' <15.5 (p 0.001) were associated with weaning success and free survival after weaning. LVEF did not predict the weaning success and survival at any time-point (p 0.230). Longitudinal function, t-IVT and native ejection, measured with LVOT VTI, are reliable parameters to predict weaning success in V-A ECMO whereas the LVEF, although dynamically changing during weaning trial, it is not.

Echocardiography-Derived Forward Left Ventricular Output Improves Risk Prediction in Systolic Heart Failure

Although it is widely used to classify patients with heart failure (HF), the prognostic role of left ventricular ejection fraction (LVEF) is debated. The aim of this study was to test the hypothesis that echocardiographic measures of forward left ventricular (LV) output, being more representative of cardiac hemodynamics, might improve risk prediction in a large cohort of patients with HF with systolic dysfunction. Consecutive stable patients with HF with LVEF <50% on guideline-recommended therapies undergoing echocardiography including the evaluation of forward LV output (i.e., LV outflow tract [LVOT] velocity-time integral [VTI], stroke volume index [SVi], and cardiac index) over a 6-year period were selected and followed for the end point of cardiac and all-cause death. Among the 1,509 patients analyzed (mean age, 71±12years; 75% men; mean LVEF, 35±9%), 328 (22%) died during a median follow-up period of 28 months (interquartile range, 14-40 months), 165 (11%) of cardiac causes. On multivariable regression analysis, LVOT VTI (P<.001), SVi (P<.001), and cardiac index (P<.001), but not LVEF (P>.05), predicted cardiac and all-cause death. The optimal prognostic cutoffs for LVOT VTI, SVi, and cardiac index were 15cm, 38mL/m2, and 2L/min/m2, respectively. Adding each of these measures to a multivariable risk model (including clinical, biohumoral, and echocardiographic markers) improved risk prediction (P<.001). Among the different measures of forward LV output, cardiac index was less accurate than LVOT VTI and SVi. The echocardiographic evaluation of forward LV output improves risk prediction in patients with HF across a wide LVEF spectrum over other well-established clinical, biohumoral, and echocardiographic prognostic markers.

Association between speckle tracking echocardiography and pressure-volume loops during cardiogenic shock development

BackgroundThe relationship between speckle tracking assessed global longitudinal strain (GLS) and Doppler-based echocardiography with basic physiological markers of cardiac function derived from pressure-volume loops is poorly elucidated.ObjectiveWe aimed to describe...

Low left ventricular outflow tract velocity time integral predicts normotensive shock in patients with acute pulmonary embolism

In this study, we found that a low LVOT VTI (<15 cm), a simple bedside point-of-care measurement, predicts normotensive shock in patients with acute intermediate-risk PE.

The left ventricular outflow tract and carotid artery velocity time integrals

The left ventricular outflow tract velocity time integral (LVOT VTI) is commonly used in the intensive care unit as a measure of stroke volume (SV) and how the SV changes in response to an intervention; therefore, the LVOT VTI is used to guide intravenous fluid management. Various peripheral Doppler surrogates are proposed to infer the LVOT VTI (e.g., measures from the common carotid artery). A recently-described, novel method of insonation has an excellent ability to detect change in the LVOT VTI. This approach raises important facets of Doppler flow and insonation error, as well as the general principles at play when using a peripheral artery to infer changes from the left ventricle. Relating the VTI of a peripheral artery to the LVOT VTI was recently described mathematically and may help clinicians think about the Doppler relationship between central and peripheral flow.

Development and Evaluation of a Natural Language Processing System for Curating a Trans-Thoracic Echocardiogram (TTE) Database.

Although electronic health records (EHR) provide useful insights into disease patterns and patient treatment optimisation, their reliance on unstructured data presents a difficulty. Echocardiography reports, which provide extensive pathology information for cardiovascular patients, are particularly challenging to extract and analyse, because of their narrative structure. Although natural language processing (NLP) has been utilised successfully in a variety of medical fields, it is not commonly used in echocardiography analysis. To develop an NLP-based approach for extracting and categorising data from echocardiography reports by accurately converting continuous (e.g., LVOT VTI, AV VTI and TR Vmax) and discrete (e.g., regurgitation severity) outcomes in a semi-structured narrative format into a structured and categorised format, allowing for future research or clinical use. 135,062 Trans-Thoracic Echocardiogram (TTE) reports were derived from 146967 baseline echocardiogram reports and split into three cohorts: Training and Validation (n = 1075), Test Dataset (n = 98) and Application Dataset (n = 133,889). The NLP system was developed and was iteratively refined using medical expert knowledge. The system was used to curate a moderate-fidelity database from extractions of 133,889 reports. A hold-out validation set of 98 reports was blindly annotated and extracted by two clinicians for comparison with the NLP extraction. Agreement, discrimination, accuracy and calibration of outcome measure extractions were evaluated. Continuous outcomes including LVOT VTI, AV VTI and TR Vmax exhibited perfect inter-rater reliability using intra-class correlation scores (ICC = 1.00, p < 0.05) alongside high R2 values, demonstrating an ideal alignment between the NLP system and clinicians. A good level (ICC = 0.75-0.9, p < 0.05) of inter-rater reliability was observed for outcomes such as LVOT Diam, Lateral MAPSE, Peak E Velocity, Lateral E' Velocity, PV Vmax, Sinuses of Valsalva and Ascending Aorta diameters. Furthermore, the accuracy rate for discrete outcome measures was 91.38% in the confusion matrix analysis, indicating effective performance. The NLP-based technique yielded good results when it came to extracting and categorising data from echocardiography reports. The system demonstrated a high degree of agreement and concordance with clinician extractions. This study contributes to the effective use of semi-structured data by providing a useful tool for converting semi-structured text to a structured echo report that can be used for data management. Additional validation and implementation in healthcare settings can improve data availability and support research and clinical decision-making.

Association between speckle tracking echocardiography and pressure-volume loop derived parameters at increasing levels of myocardial damage in a porcine model of acute cardiogenic shock

Abstract Background Echocardiography is a diagnostic cornerstone in acute cardiovascular care. However, the relationship between speckle tracking assessed global longitudinal strain (LS) and Doppler-based echocardiography with basic physiological markers of cardiac function derived from pressure-volume loops remains poorly elucidated, especially with increasing levels of myocardial damage. Objectives We aimed to describe the association between LS and Doppler-based echocardiography and direct measurements of central hemodynamic parameters from conductance catheter-based pressure-volume loops in an animal model with increasing left ventricular (LV) dysfunction. Methods Twelve Danish landrace pigs weighing 75-80 kg were used. All instrumentations were performed percutaneously, including placement of a conductance catheter in the LV. Progressive LV dysfunction was induced by stepwise embolization trough the left main coronary artery every three minutes until a 50% reduction in cardiac output or mixed venous saturation, compared to baseline, or a mixed venous saturation &amp;lt;30%. Echocardiography was performed through a subxiphoid midline incision, and was done at baseline and 90 seconds after each injection. Results With progressive LV dysfunction, mean cardiac output decreased from 5.6 l/min (SD: 0.9) to 2.1 l/min (SD: 0.9) and mean mixed venous saturation deteriorated from 61.1%(SD: 7.9) to 35.3% (SD: 6.1). Mean LS and LV outflow tract velocity time integral (LVOT VTI) declined from -13.8% (SD 3.0) to -6.1% (SD: 2.0) and 16.9 cm (SD: 2.6) to 7.8 cm (SD: 1.8), respectively (Figure 1). LS and LVOT VTI showed the strongest correlation to stroke work in unadjusted univariate regression (r2=0.53 and r2=0.49, respectively. p&amp;lt;0.01 for both). LS correlated significantly, but modest, with stroke volume (r2=0.46, p&amp;lt;0.01), end-systolic elastance (r2=0.32, p&amp;lt;0.01), systolic blood pressure (r2=0.37, p&amp;lt;0.01), ventriculo-arterial coupling(r2=0.34, p&amp;lt;0.01), and arterial elastance (r2=0.23, p&amp;lt;0.01) (Figure 2). In a multivariate regression analysis, LS showed significant correlation with stroke work, systolic blood pressure, and end-diastolic wall stress (r2=0.60, p&amp;lt;0.01). Conclusion In an animal model of acute progressive LV dysfunction, echocardiographic and conductance catheter-based measurements changed significantly. LS and LVOT VTI displayed the earliest and the largest alterations with increased myocardial damage and LS showed moderate correlations with contractility, arterial elastance and ventriculo-arterial coupling. This indicates that LS is a marker of overall ventricular performance.Echocardiographic changes from baselineScatter plot of LS and hemodynamics

Machine learning score focused only on echocardiographic data to predict in-hospital outcomes in ICCU patients. A study from the ADDICT ICCU cohort

Abstract Background While several studies have shown the strong prognostic value of several transthoracic echocardiography (TTE) parameters in patients admitted in intensive cardiac care unit (ICCU), the interest of a severity score integrating these parameters has not been established. Machine learning (ML) represents an innovative and accurate statistical method to embed TTE parameters into a scoring system. Purpose To investigate the feasibility and accuracy of ML integrating TTE parameters measured at admission in ICCU to predict in-hospital major adverse cardiovascular events (MACE) and to compare its performance with existing scores. Methods In April 2021, 1,499 patients admitted to 39 French ICCU were included in the ADDICT-ICCU Cohort (NCT05063097). A comprehensive TTE was performed within the first 24 hours of admission. Twenty TTE parameters were systematically collected. ML involved automated feature selection by Boruta to select variables and prevent model overfitting. Several ML models (LASSO, Random Forest and XGBoost) were then trained on 70% of patients and evaluated on the other 30% as internal validation. Their performances were compared against standard logistic regression model, using receiver operating characteristics (ROC) curves, precision-recall (PR) curves and area-under-the curves (AUC). The primary composite outcome was in-hospital MACEs defined by all-cause mortality, cardiogenic shock (requiring medical or mechanical haemodynamic support) and resuscitated cardiac arrest. The external validation cohort of the ML score was performed in another center on 300 patients. Results Of 1,499 consecutive patients screened (63±15 years, 70% male), MACEs occurred in 67 patients (4.5%) including: 27 (1.8%) deaths, 38 (2.53%) cardiogenic shocks, and 14 (0.9%) resuscitated cardiac arrests. To build the ML models, 5 TTE parameters were selected as being the most important in predicting MACEs: LVOT VTI, E/e’ ratio, sPAP, TAPSE, and LVEF. The XGBoost model showed the best performance compared with the other ML models (AUROC for XGBoost: 0.83, Random-forest: 0.81, LASSO regression 0.79 and to a regression model: 0.76). Using the XGBoost model as our final ML-score, SHAP values for the parameters were: 0.047 for LVOT VTI, 0.041 for E/e’ ratio, 0.028 for SPAP, 0.021 for TAPSE and 0.01 for LVEF. Our ML-score exhibited a higher AUC compared with existing scores (TIMI, GRACE, qSOFA, Acute-HF) (Figure 1), and an incremental prognostic value for predicting in-hospital MACEs over and above clinical or biological data (Chi-square 59.72 p&amp;lt;0.001; C-Index 0.8 [0.71;0.89], p=0.012) (Figure 2). Conclusion The ML score including only TTE parameters exhibited a higher prognostic value to predict in-hospital MACE compared with any other existing traditional methods in patients admitted in ICCU. This ML score could be implemented in clinical practice given its ease of use (only 5 TTE parameters to analyze) and its prognostic implication.Figure 1.PerformanceFigure 2.Prognostic value

Determinants of right ventricular systolic dysfunction among patients with left heart failure in a Ghanaian hospital.

The presence of right ventricular dysfunction affects outcomes in patients with left heart failure. We assessed the determinants of right ventricular systolic dysfunction (RVSD) among patients with left heart failure presenting to the Korle Bu Teaching Hospital of Ghana. Consecutive patients with left heart failure who were 18 years and above were prospectively enrolled and assessed for evidence of RVSD by measuring the tricuspid annular plane systolic excursion, the peak velocity of the tricuspid annulus in systole (RV S'), the two-dimensional right ventricular fractional area change (RV FAC) and the right ventricular myocardial performance index (RV MPI). Two hundred and seventy participants were enrolled, of whom 75.2% had at least one abnormal index of right ventricular systolic function. The prevalence of RVSD was significantly higher among those with non-hypertensive heart failure (85.3 vs 66.0%, p < 0.001). The left ventricular outflow tract velocity-time integral (LVOT VTI) was strongly correlated with the RV FAC and an LVOT VTI < 9.8 cm predicted the presence of an RV FAC < 35% with a sensitivity of 81.5% and specificity of 81.9% [area under the curve 0.882; 95% confidence interval (CI): 0.838-0.926, p < 0.001]. Independent predictors of the presence of RVSD included a transmitral E/A > 2 [odds ratio (OR) = 4.684, 95% CI: 1.521-14.428, p = 0.007), left ventricular ejection fraction < 40% (OR = 4.205, 95% CI: 1.643-10.760, p = 0.003), pulmonary artery systolic pressure (PASP) ≥ 35 mmHg (OR = 2.434, 95% CI: 1.012-5.852, p = 0.047) and systemic systolic blood pressure (SBP) < 140 mmHg (OR = 2.631, 95% CI: 1.152-6.011, p = 0.022). RVSD was common in these Ghanaian patients with left heart failure. Left ventricular function, SBP and PASP were independent predictors of the presence of RVSD. Pending further validation, the LVOT VTI may serve as a useful surrogate or screening tool for RVSD in these patients.

Abstract 15501: Effects of Vericiguat on Right Ventricular Function in Chronic Heart Failure Patients

Introduction: Despite the beneficial clinical effects of vericiguat in chronic heart failure, the potential effects of vericiguat therapy on right ventricular (RV) function remain poorly defined. Hypothesis: We sought to evaluate the effects of vericiguat on RV function in chronic heart failure patients. Methods: We performed a prospective non-randomized single center study enrolling 24 consecutive HFrEF outpatients who were receiving stable heart failure therapy for at least 3 months. All patients received vericiguat 2,5 mg qd at baseline and up-titration was performed on a bi-weekly basis to the target dose of 10 mg qd. At baseline and at 3 month follow-up all patients underwent clinical, biochemical and echocardiographic evaluation. Improved RV function was defined as any improvement in TAPSE between baseline and 3 months. Results: During follow-up we observed a significant overall improvement of TAPSE (18.5±4.2 mm vs. 21.3±4.7 mm; P=0.03) and TR gradient (35±10 mmHg vs. 29±8 mmHg; P=0.04). RV function improved in 17 patients (70%; Group A) and remained unchanged in 7 (30%) patients (Group B). At baseline, the two groups did not differ in gender (male; 100% in Group A vs. 90% in Group B; P=0.37), age (64±9 years vs. 61±9 years; P=0.59), NYHA class (2.9±0.5 vs. 3.1± 0.3; P=0.39), or heart failure etiology (ishemic: 64% vs. 71%; P=0.76). Heart failure therapy was also comparable: ARNI (94% vs. 100%; P=0.53), beta blockers (94% vs. 100%; P=0.53), MRA (100% vs. 100%), SGLT2i (100% vs. 86%; P=0.12) and loop diuretics (59% vs. 57%; P=0.94). We found no differences in baseline LVEF (30±6% vs. 29±4%; P=0.73), LVOT VTI (15±3 cm vs. 14±5 cm; P=0.34), LVEDV (219±51 mL vs. 197±56 mL; P=0.39), TAPSE (17±3 mm vs. 18±3; P=0.68), RVIDd (39±4 mm vs. 38±3 mm; P=0.58) and TR gradient (34±8 mmHg vs. 38±11 mmHg; P=0.38). Both groups received similar doses of vericiguat (8.5±2.8 mg in Group A vs. 6.8±2.9 mg in Group B; P=0.19). Compared to Group B, we found significantly lower baseline NT-proBNP serum levels in Group A (1888±1973 pg/mL vs. 6373±5465 pg/mL; P=0.009). Conclusions: Vericiguat therapy may be associated with improved RV function in chronic heart failure patients. The effects appear to be particulary pronounced in patients with lower NT-proBNP levels.

Correlation of Common Carotid Artery Blood Flow Parameters With Transthoracic Echocardiographic Cardiac Output for Assessing Fluid Responsiveness After Passive Leg Raising (PLR) Test in Critically Ill Patients.

Introduction The passive leg raising (PLR) test is a simple, non-invasive method of knowing fluid responsiveness by acting as an internal-fluid challenge. The PLR test coupled with a non-invasive assessment of stroke volume would be the ideal method to assess fluid responsiveness. This study aimed to determine the correlation between transthoracic echocardiographic cardiac output (TTE-CO)and common carotid artery blood flow(CCABF) parameters in determining fluid responsiveness with the PLR test. Methods We performed a prospective observational study on 40 critically ill patients. Patients were evaluated with a 7-13 MHz linear transducer probe for CCABFparameters calculated using time-averaged mean velocity (TAmean) and with a 1-5 MHz cardiac probe equipped with tissue doppler imaging (TDI) for TTE-CO calculated using left ventricular outflow tract velocity time integral (LVOT VTI) with an apical five-chamber view. Two separate PLR tests (five minutes apart) were done within 48 hours of ICU admission. The first PLR test was to assess the effects on TTE-CO. The second PLR test was performed to assess the effects on CCABF parameters. Patients were designated as fluid responders (FR) if changes in TTE-CO (Δ TTE-CO) ≥ 10 %. Results A positive PLR test was observed in 33% of patients. A strong correlation was present between absolute values of TTE-CO calculated using LVOT VTI and the absolute values of CCABF calculated using TAmean (r=0.60, p<0.05). However, a weak correlation was found between Δ TTE-CO and changes in CCABF (Δ CCABF) during the PLR test (r=0.05, p<0.74). A positive PLR test response could not be detected by Δ CCABF (area under the curve (AUC): 0.59 ± 0.09). Conclusions We found a moderate correlation between TTE-CO and CCABF at baseline. However,Δ TTE-COhad a very poor correlation with Δ CCABF, during the PLR test. Considering this, CCABF parameters may not be recommended as a means to detect fluid responsiveness with PLR tests in critically ill patients.

Echocardiographic Evaluation of His Bundle Pacing in Patients with Prolonged PR Intervals.

Patients with PR intervals >240ms have atrio-ventricular (AV) dyssynchrony, which can increase risk of atrial fibrillation and all-cause mortality. When requiring pacing, long AV delays (AVDs) have been programmed to avoid ventricular dyssychrony. His bundle pacing (HBP) may provide improved AV synchrony in patients with prolonged PR. 10 patients with sinus node dysfunction and prolonged PR who received HBP were studied. Real-time echocardiographic was performed with 3 pacemaker modes (RV septal, non-selective HBP, and selective HBP) using the following pacemaker settings: control (no ventricular pacing), pacing with AVD of 180ms, 150ms, 120ms, 100ms, and 70ms. Echocardiographic Doppler measurements: EA/RR, >40% = AV synchrony; E/e', <8 = normal left atrial pressure; pulmonic-to-aortic pre-ejection time difference, <40ms = interventricular synchrony; septal-to-lateral wall activation time difference, <56ms = intraventricular synchrony; and LVOT VTI. Unpaired T test was used to evaluate for significance. Exclusion criteria: persistent atrial fibrillation, second-degree AV block. Compared to control programming, HBP showed a 31.5% increase in EA/RR time, a decrease in E/e' of 26.9%, and an increase in the LVOT VTI of 21.3%. Compared to RV septal pacing, there was a similar increase in LVOT VTI. These findings met statistical significance and were considered optimal based on Doppler echocardiography findings primarily at AVDs of 150ms and 120ms. Comparisons between selective and non-selective pacing were not significantly different. Compared to controls and RV septal pacing, physiologic His bundle pacing was shown to increase markers of AV synchrony and LV stroke volume while maintaining ventricular synchrony.

An Assessment of Carotid Flow Time Using a Portable Handheld Ultrasound Device: The Ideal Tool for Guiding Intraoperative Fluid Management?

Volume resuscitation is a cornerstone of modern anesthesia care. Finding the right balance to avoid inadequate or excess volume administration is often difficult to clinically discern and can lead to negative consequences. Pulse pressure variation is often intraoperatively used to guide volume resuscitation; however, this requires an invasive arterial line and is generally only applicable to patients who are mechanically ventilated. Unfortunately, without a pulmonary artery catheter or another costly noninvasive device, performing serial measurements of cardiac output is challenging, time-consuming, and often impractical. Furthermore, noninvasive measures such as LVOT VTI require significant technical expertise as well as access to the chest, which may not be practical during and after surgery. Other noninvasive techniques such as bioreactance and esophageal Doppler require the use of costly single-use sensors. Here, we present a case report on the use of corrected carotid flow time (ccFT) from a portable, handheld ultrasound device as a practical, noninvasive, and technically straightforward method to assess fluid responsiveness in the perioperative period, as well as the inpatient and outpatient settings.

Possibilities of a portable electrocardiogram and pulse wave recorder in detecting left ventricular systolic dysfunction

Highlights. The article presents a novel and unique method for assessment of left ventricular systolic disfunction using electrocardiography and photoplethysmography data. This method will improve and simplify the detection of cardiovascular diseases.Aim. To evaluate left ventricular (LV) systolic function using electrocardiogram (ECG) and photoplethysmogram (PPG) signals recorded by a single-channel ECG and PPG-based monitor.Methods. The prospective study included 489 patients over 18 years old with various cardiovascular diseases. All participants underwent echocardiography to determine the main indicators of LV systolic function: LV ejection fraction (EF), LV outflow tract velocity time integral (LVOT VTI), and global longitudinal strain (GLS). Moreover, all patients underwent 1-lead ECG and PPG recording using a single-channel ECG and PPG-based monitor (CardioQvark). The obtained data were analyzed, and ROC curve analysis was performed.Results. We have identified ECG and PPG parameters associated with a decrease in LV contractile function. During the analysis, the ECG, T-wave amplitude (TA) and RonsF parameters showed the highest diagnostic accuracy. With EF below 55%, the area under the ROC curve (AUC) was 0.822, sensitivity (Se) 80%, specificity (Sp) 69% in EF below 55% in TA; in RonsF AUC was 0.743, Se 81%, Sp 77%. With EF below 40%, AUC was 0.915, Se 85%, Sp 83% in TA, and in RonsF AUC was 0.844, Se 82%, Sp 82%. Diagnostic accuracy of ECG signals in case of LVOT VTI lower than 16 cm was measured: TA (AUC 0.755, Se 82%, Sp 70%), RonsF (AUC 0.620, Se 77%, Sp 72%). PPG signals were not significantly associated with reduced EF; however, the pulse wave parameters were associated with lower LVOT VTI: in DP-B0 AUC was 0.687, Se 71%, Sp 74%. The combination of ECG and PPG signals was significantly associated with EF below 40% (RonsF * DP-SEP (AUC 0.877, Se 86%, Sp 85%). ECG and PPG signals were not associated with LV GLS.Conclusion. Assessment of LV systolic function can be performed by analyzing ECG and PPG signals recorded using a portable single-channel CardioQvark monitor.

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Right ventricular cardiac resynchronization therapy in patients with right ventricular conduction delay and heart failure

Echocardiography- versus intracardiac electrocardiogram-based optimization of cardiac resynchronization therapy: A systematic review.

This systematic review aimed to evaluate the performance of echocardiography-based programming in comparison with the intracardiac electrocardiogram (IEGM)-based method for the optimization of cardiac resynchronization therapy (CRT). A literature review was conducted using digital databases to systematically identify the studies reporting CRT optimization through echocardiography compared with IEGM. Detailed patient-level study characteristics including the type of study, sample size, therapy, the New York Heart Classification (NYHA) status, lead placement, and other parameters were abstracted. Finally, postprogramming outcomes were extracted for each article. In a total of 11 studies, 919 patients were recruited for the final analysis. Overall, 692 (75.29%) were males. The mean duration of the QRS complex in our study population ranged from 145.2± 21.8ms to 183 ± 19.9ms. There was an equal improvement in the NYHA class between the two methods while the left ventricular ejection fraction (LVEF) demonstrated an improvement by IEGM. Many studies supported IEGM to increase the 6-minute walk test and left ventricular outflow tract velocity time interval (LVOT VTI) when compared to echocardiography. The mean time for echocardiography-based optimization was 60.15 min while that of IEGM-based optimization was 6.65 min. IEGM is an alternative method for CRT optimization in improving the NYHA class, LVEF, and LVOT VTI, and is less time-consuming when compared to the echocardiography-based methods.

1082 LEFT VENTRICULAR FUNCTION ESTIMATION: WHEN VOLUMES MEASUREMENT IS NOT FEASIBLE

Abstract Background Contrast echocardiography is mainly performed for the assessment of global left ventricular (LV) function, left ventricular ejection fraction (LVEF) and stroke volume (SV) thanks to improved visualization of endocardial LV borders. Neverless in some patients estimation of ventricular volumes could be difficult also with contrast and assessment of LVEF can be really hard. The aim of the study was to find alternative methods for LV function evaluation independent from volume assessment. Methods Patients who underwent a contrast echocardiography between October 2015 and September 2022 were enrolled in the study. A complete transthoracic echocardiography was performed and Sonovue contrast was then injected. End-diastolic and end-systolic LV volume in apex 4 and 2 chamber views, were measured prior and after injecting contrast. Left ventricular outflow tract diameter (LVOTd) was measured and LVOT velocity time integral was traced in order to calculate LVOT VTI Stroke Volume (product of LVOT cross sectional area to the LVOT VTI). LVOT VTI SV obtained during traditional echocardiography was then compared to LV SV calculated as the difference between end-diastolic and end-systolic volume traced after contrast. After intravenous bolus injection of Sonovue pulmonary transit time (PTT) was recorded as contrast agent's transit time from right to left ventricle in apex 4 chamber view (seconds). PTT was then compared to measures of LV function: LVEF with and without Sonovue and LV SV with contrast. Results 149 patients were enrolled in the study, 86 had history of CAD, 31 presented dilatative cardiomyopathy, 5 hypertrophic cardiomyopathy (HMC), 113 had arterial hypertension, and 37 diabetes. Medium BMI was 28. The main indications for contrast echocardiography were measurement of EF and exclusion of thrombi in LV apex. LVOT VTI SV was calculated in 126 patients. In the same patients LVEF Stroke Volume was calculated. A strong correlation (P value &amp;lt; 0.0001) between LVOT VTI SV and LV SV was found (Figure 1). PPT was calculated in 74 patient and in the same patients LVEF with and without contrast (Figure 2) and LV SV were calculated. A strong correlation (P-value &amp;lt;0.048, p-value&amp;lt;0.006 and p-value &amp;lt; 0.046 respectively) was found. Conclusion This study demonstrates that, besides extremely poor acoustic windows, bedside echocardiography, with and without contrast, can be used to estimate LV function using volume-independent methods like PTT and LVOT VTI SV.