Left Ventricular Ejection Time Research Articles

Artificial Intelligence Applied to Electrical and Non-Invasive Hemodynamic Markers in Elderly Decompensated Chronic Heart Failure Patients

Objectives: The first aim of this study was to assess the predictive power of Tend interval (Te) and non-invasive hemodynamic markers, based on bioimpedance in decompensated chronic heart failure (CHF). The second one was to verify the possible differences in repolarization and hemodynamic data between CHF patients grouped by level of left ventricular ejection fraction (LVEF). Finally, we wanted to check if repolarization and hemodynamic data changed with clinical improvement or worsening in CHF patients. Methods: Two hundred and forty-three decompensated CHF patients were studied by 5 min ECG recordings to determine the mean and standard deviation (TeSD) of Te (first study). In a subgroup of 129 patients (second study), non-invasive hemodynamic and repolarization data were recorded for further evaluation. Results: Total in-hospital and cardiovascular mortality rates were respectively 19 and 9%. Te was higher in the deceased than in surviving subjects (Te: 120 ± 28 vs. 100 ± 25 ms) and multivariable logistic regression analysis reported that Te was related to an increase of total (χ2: 35.45, odds ratio: 1.03, 95% confidence limit: 1.02–1.05, p < 0.001) and cardiovascular mortality (χ2: 32.58, odds ratio: 1.04, 95% confidence limit: 1.02–1.06, p < 0.001). Subjects with heart failure with reduced ejection fraction (HFrEF) reported higher levels of repolarization and lower non-invasive systolic hemodynamic data in comparison to those with preserved ejection fraction (HFpEF). In the subgroup, patients with the NT-proBNP reduction after therapy showed a lower rate of Te, heart rate, blood pressures, contractility index, and left ventricular ejection time in comparison with the patients without NT-proBNP reduction. Conclusion: Electrical signals from ECG and bioimpedance were capable of monitoring the patients with advanced decompensated CHF. These simple, inexpensive, non-invasive, easily repeatable, and transmissible markers could represent a tool to remotely monitor and to intercept the possible worsening of these patients early by machine learning and artificial intelligence tools.

Detecting aortic valve stenosis based on the non-invasive blood pressurewaveform-a proof of concept study.

The incidence of aortic valve stenosis (AoS) increases with age, and once diagnosed, symptomatic severe AoS has a yearly mortality rate of 25%. AoS is diagnosed with transthoracic echocardiography (TTE), however, this gold standard is time consuming and operator and acoustic window dependent. As AoS affects the arterial blood pressure waveform, AoS-specific waveform features might serve as a diagnostic tool. Aim of the present study was to develop a novel, non-invasive, AoS detection model based on blood pressures waveforms. This cross-sectional study included patients with AoS undergoing elective transcatheter or surgical aortic valve replacement. AoS was determined using TTE, and patients with no or mild AoS were labelled as patients without AoS, while patients with moderate or severe AoS were labelled as patients with AoS. Non-invasive blood pressure measurements were performed in awake patients. Ten minutes of consecutive data was collected. Several blood pressure-based features were derived, and the median, interquartile range, variance, and the 1st and 9th decile of the change of these features were calculated. The primary outcome was the development of a machine-learning model for AoS detection, investigating multiple classifiers and training on the area under the receiver-operating curve (AUROC). In total, 101 patients with AoS and 48 patients without AoS were included. Patients with AoS showed an increase in left ventricular ejection time (0.02s, p = 0.001), a delayed maximum upstroke in the systolic phase (0.015s, p < 0.001), and a delayed maximal systolic pressure (0.03s, p < 0.001) compared to patients without AoS. With the logistic regression model, a sensitivity of 0.81, specificity of 0.67, and AUROC of 0.79 were found. The majority of the population without AoS was male (85%), whereas in the population with AoS this was evenly distributed (54% males). Age was significantly (5years, p < 0.001) higher in the population with AoS. In the present study, we developed a novel model able to distinguish no to mild AoS from moderate to severe AoS, based on blood pressure features with high accuracy. Clinical registration number: The study entailing patients with TAVR treatment was registered at ClinicalTrials.gov (NCT03088787, https://clinicaltrials.gov/ct2/show/NCT03088787 ). The study with elective cardiac surgery patients was registered with the Netherland Trial Register (NL7810, https://trialsearch.who.int/Trial2.aspx?TrialID=NL7810 ).

Is the Corrected Carotid Flow Time a Clinically Acceptable Surrogate Hemodynamic Parameter for the Left Ventricular Ejection Time?

ObjectiveThe corrected left ventricular ejection time (cLVET) comprises the phase from aortic valve opening to aortic valve closure corrected for heart rate. As a surrogate measure for cLVET, the corrected carotid flow time (ccFT) has been proposed in previous research. The aim of this study was to assess the clinical agreement between cLVET and ccFT in a dynamic clinical setting. MethodsTwenty-five patients with severe aortic valve stenosis (AS) were selected for transcatheter aortic valve replacement (TAVR). The cLVET and ccFT were derived from the left ventricular outflow tract (LVOT) and the common carotid artery (CCA) respectively, using pulsed wave Doppler ultrasound. Bazett's (B) and Wodey's (W) equation were used to calculate cLVET and ccFT. Measurements were performed directly before (T1), and after (T2) TAVR. Correlation, Bland-Altman, and concordance analyses were performed. ResultsThe cLVET decreased from T1 to T2 (p<0.001), with a relative reduction of 11% (B) and 9% (W). The ccFT decreased (p<0.001) with a relative reduction of 12% (B) and 10% (W). The correlation between cLVET and ccFT was strong for B (ρ=0.74, p<0.001), and W (ρ=0.81, p<0.001). The bias was -39 ms (B) and -37 ms (W), and the upper and lower level of agreement were 19 ms and -98 ms (B) and 5 ms and -78 ms (W), respectively. The trending ability between cLVET and ccFT was good (concordance 96%) for both B and W. ConclusionIn TAVR patients, the clinical agreement between cLVET and ccFT was acceptable, indicating that ccFT could serve as a surrogate measure for cLVET.

Assessing Passive Leg Raise Test in Pediatric Shock Using Electrical Cardiometry

AbstractPassive leg raise (PLR) is widely used to incite an autobolus to assess fluid responsiveness in adults; however, there is a paucity of studies exploring its utility in children. Our study aimed to analyze the efficacy of PLR in determining fluid responsiveness in children presenting with shock using electrical cardiometry. Patients in the age group of 0 to 20 years who presented in shock to our children's hospital emergency department were evaluated. Multiple hemodynamic metrics including, heart rate, systolic/diastolic blood pressure, cardiac output (CO), stroke index, stroke volume (SV), flow time corrected (FTC), and left ventricular ejection time (LVET) were recorded using the noninvasive ICON device and compared at baseline and post-PLR. A total of 68 patients had pre- and post-PLR data available for review between June and July 2022. Median age was 7 years (54% male); most common etiology was hypovolemic (67.6%) shock. Following PLR, there was no significant change in most hemodynamic parameters, including SV and CO; however, there was a significant difference in FTC (301 [pre-PLR] vs. 307 [post-PLR], p = 0.016) (ms) and LVET (232 [pre-PLR] vs. 234 [post-PLR], p = 0.014) (ms). A significantly higher proportion of children diagnosed with septic shock demonstrated fluid responsiveness (ΔSV ≥ 10% from baseline) compared with those with hypovolemic shock (p = 0.036). This study demonstrated no identifiable fluid responsiveness (ΔSV ≥ 10% from baseline) following PLR; however, a significantly higher proportion of children suffering from septic shock demonstrated fluid responsiveness compared with those with hypovolemic shock. Larger studies are needed to further assess the utility of PLR, as well as other modalities, in determining fluid responsiveness in children.

Mechanocardiography detects improvement of systolic function caused by resynchronization pacing.

Objective.Cardiac resynchronization therapy (CRT) is commonly used to manage heart failure with dyssynchronous ventricular contraction. CRT pacing resynchronizes the ventricular contraction, while AAI (single-chamber atrial) pacing does not affect the dyssynchronous function. This study compared waveform characteristics during CRT and AAI pacing at similar pacing rates using seismocardiogram (SCG) and gyrocardiogram (GCG), collectively known as mechanocardiogram (MCG).Approach.We included 10 patients with heart failure with reduced ejection fraction and previously implanted CRT pacemakers. ECG and MCG recordings were taken during AAI and CRT pacing at a heart rate of 80 bpm. Waveform characteristics, including energy, vertical range (amplitude) during systole and early diastole, electromechanical systole (QS2) and left ventricular ejection time (LVET), were derived by considering 6 MCG axes and 3 MCG vectors across frequency ranges of >1 Hz, 20-90 Hz, 6-90 Hz and 1-20 Hz.Main results.Significant differences were observed between CRT and AAI pacing. CRT pacing consistently exhibited higher energy and vertical range during systole compared to AAI pacing (p< 0.05). However, QS2, LVET and waveform characteristics around aortic valve closure did not differ between the pacing modes. Optimal differences were observed in SCG-Y, GCG-X, and GCG-Y axes within the frequency range of 6-90 Hz.Significance.The results demonstrate significant differences in MCG waveforms, reflecting improved mechanical cardiac function during CRT. This information has potential implications for predicting the clinical response to CRT. Further research is needed to explore the differences in signal characteristics between responders and non-responders to CRT.

Cardiac Autonomic Balance Is Altered during the Acute Stress Response in Adolescent Major Depression-Effect of Sex.

Autonomic nervous system (ANS) abnormalities are associated with major depressive disorder (MDD) already at adolescent age. The majority of studies so far evaluated parasympathetic and sympathetic branches of ANS individually, although composite indices including cardiac autonomic balance (CAB) and cardiac autonomic regulation (CAR) seem to measure ANS functioning more comprehensively and thus could provide better psychopathologies' predictors. We aimed to study CAB and CAR derived from high-frequency bands of heart rate variability and left ventricular ejection time during complex stress response (rest-Go/NoGo task-recovery) in MDD adolescents with respect to sex. We examined 85 MDD adolescents (52 girls, age: 15.7 ± 0.14 yrs.) and 80 age- and sex-matched controls. The MDD group showed significantly reduced CAB compared to controls at rest, in response to the Go/NoGo task, and in the recovery phase. Moreover, while depressed boys showed significantly lower CAB at rest and in response to the Go/NoGo task compared to control boys, depressed girls showed no significant differences in evaluated parameters compared to control girls. This study for the first time evaluated CAB and CAR indices in drug-naïve first-episode diagnosed MDD adolescents during complex stress responses, indicating an altered cardiac autonomic pattern (i.e., reciprocal sympathetic dominance associated with parasympathetic underactivity), which was predominant for depressed boys.

Short versus long-term anticoagulation for left ventricular thrombosis resolution during vitamin k antagonist therapy

Abstract Background The optimal duration of anticoagulant therapy to achieve thrombus resolution and prevent cardioembolic events in left ventricular thrombosis (LVT) has not yet been established. Purpose The purpose of our study is to evaluate the incidence of LVT resolution at 3 versus 12 months of vitamin K antagonists (VKAs) therapy. Methods Consecutive patients diagnosed with LVT and treated with VKAs for at least 12 months at 5 anticoagulant outpatient clinics in Italy were retrospectively included. The primary effectiveness outcome was on-treatment thrombus resolution while the secondary was objectively documented on-treatment acute ischemic stroke, peripheral embolism, and myocardial infarction at 12-months follow-up. Safety outcomes were on-treatment major and clinically relevant non-major bleedings at 12-months follow-up as defined by the ISTH criteria. Cumulative incidences of thrombus resolution with 95% confidence intervals (CIs) were calculated while other outcomes were descriptively reported. Multivariable Cox hazards models were calculated using age, sex, reduced left ventricular ejection fraction (EF &amp;lt; 35%), VKAs monotherapy, and time in therapeutic range (TTR) below 60% as covariates for thrombus persistence at 12-months of follow-up. Results Out of 95 patients, 87 were finally included (Table) and 8 excluded due to the lack of relevant data. Median age was 67 years and 75.9% were men. A total of 64.4% of patients had acute myocardial infarction as risk factor for LVT development while 21.8% and 5.7% of patients had dilated and primary hypertrophic cardiomyopathy, respectively. A reduced EF and atrial fibrillation were present in 77.0% and 19.5% of patients, respectively. All but one patient received warfarin with a median TTR of 54%, and 35.5% of patients did not receive concomitant antiplatelet therapy. All included patients received VKAs for at least 12-months. The 3 and 12 month cumulative incidences (Figure) of thrombus resolution were 34.5% (95% CI, 24.7%-44.5%) and 68.3% (95% CI, 57.2%-77.1%), respectively. At multivariable Cox regression analysis, the presence of a reduced EF appeared to be associated with a higher risk of thrombus persistence at 12-months follow-up (Hazard Ratio 3.09; 95% CI 1.27-7.55; p=0.013). During 12-months follow-up, two patients (2.3%) had acute ischemic stroke at 4 and 7 months from the start of VKAs therapy. Three patients (3.4%) had a major and 5 (5.7%) a clinically relevant non-major bleeding that occurred within the first three months of VKAs. Conclusions A 12-month course of anticoagulant therapy with VKA appeared to be effective and safe in patients with LVT and appeared to be associated with a higher cumulative incidence of LVT resolution than a 3-month course. A reduced left ventricular EF was associated with a higher risk of LVT persistence. Whether anticoagulant agents with improved ease-of-use and safety profile are effective in this setting remains undefined.Baseline patients' characteristicsCumulative incidences of LVT resolution

Left Ventricular Ejection Time Estimation from Blood Pressure and Photoplethysmography Signals Based on Tidal Wave

Left ventricular ejection time (LVET) is an important parameter for assessing cardiovascular disorders. In a medical office, it is typically measured using the Tissue Doppler Imaging technique, but new wearable devices have led to a growing interest in integrating this parameter into them, increasing accessibility to personalized healthcare for users and patients. In the cardiovascular domain, photoplethysmography (PPG) is a promising technology that shares two distinctive features with invasive arterial blood pressure (ABP) tracing: the tidal wave (TDW) and the dicrotic wave (DCW). In the early years of cardiovascular research, the duration of the dicrotic point was initially linked to the ending phase of left ventricular ejection. Subsequent studies reported deviations from the initial association, suggesting that the ejection period is related to the tidal wave feature. In this current study, we measured left ventricular ejection time in both ABP and PPG waveforms, considering recent research results. A total of 27,000 cardiac cycles were analyzed for both afore-mentioned signals. The reference value for ejection time was computed based on the T-wave segment duration from the electrocardiogram waveform. In lower blood pressure, which is associated with decreased heart contractility, the results indicated an underestimation of −29 ± 19 ms in ABP and an overestimation of 18 ± 31 ms in PPG. On the other side of the spectrum, during increased contractility, the minimum errors were −3 ± 18 ms and 4 ± 33 ms, respectively. Since the tidal wave feature is strongly affected by arterial tree compliance, the population evaluation results indicate a Pearson’s correlation factor of 0.58 in the ABP case, and 0.53 in PPG. These findings highlight the need for advanced compensation techniques, in particular for PPG assessment, to achieve clinical-grade accuracy.

Artificial intelligence technology applied to an unoccluded catheter for recognition of hemodynamic changes

This study seeks to provide a reliable means for physicians to diagnose hemorrhagic complications associated with patent ductus arteriosus (PDA) in extremely low birth weight (ELBW) infants. We employ the YOLOv4 algorithm to analyze cardiac parameters from the echocardiography device's ultrasonic wave, such as left ventricular ejection time (LVET), left ventricular internal dimension-diastole (LVIDd), left ventricular internal dimension-systole (LVIDs), posterior wall thickness at end-systole (HES), and RR interval. The proposed model has achieved an impressive average detection accuracy of 89.4% for these five parameters. Additionally, the further evaluation of cardiac function can be done by deriving the end-systolic wall stress (ESWS) and left ventricle rate-corrected mean velocity of circumferential fiber shortening (mVcFc) values from these parameters. As a result, it indicates that the accuracy of ESWS and mVcFc values is 88.7% and 90.3%, respectively. With this deep learning-based approach, physicians can confidently evaluate the cardiac function of ELBW infants and diagnose PDA-related hemorrhagic complications.

Impact of bimonthly repeated total sleep deprivation and recovery sleep on cardiovascular indices.

Since short sleep duration adversely affects cardiovascular (CV) health, we investigated the effects of exposures to total sleep deprivation (TSD), and baseline (BL) and recovery (REC) sleep on CV measures. We conducted a 5-day experiment at months 2 and 4 in two separate studies (N = 11 healthy adults; 5 females). During these repeated experiments, CV measures [stroke volume (SV), cardiac index (CI), systemic vascular resistance index (SVRI), left ventricular ejection time, heart rate (HR), systolic and diastolic blood pressure (SBP and DBP) and mean arterial pressure (MAP)] were collected at three assessment time points after: (1) two BL 8 h time-in-bed (TIB) sleep opportunity nights; (2) a TSD night; and (3) two REC 8-10 h TIB nights. CV measures were also collected pre-study. TSD significantly increased SV and CI, and decreased SVRI, with large effect sizes, which importantly were reversed with recovery, indicating these measures are possible novel biomarkers for assessing the adverse consequences of TSD. Pre-study SV, CI, SVRI, HR, SBP, and MAP measures also significantly associated with TSD CV responses at months 2 and 4 [Pearson's r: 0.615-0.862; r2 : 0.378-0.743], indicating they are robust correlates of future TSD CV responses. Our novel findings highlight the critical impact of sleep on CV health across time.

Diagnostic capabilities of echocardiographic indicators of acceleration time and the ratio of acceleration time to total left ventricular ejection time in the assessment of severe aortic stenosis in patients with reduced left ventricular ejection fraction

Objectives: 1) to evaluate the diagnostic capabilities of AT and AT/ET in determining severe AS in patients with reduced LV EF and low stroke volume.2) to determine the threshold values for AT and AT/ET in the diagnosis of severe AS in patients with low stroke volume and low transaortic gradient.Materials and methods. This is prospective single center study included 70 patients with low transaortic pressure gradient, reduced LV ejection fraction was and severe aortic stenosis. All patients have been examined from 2017 to 2022. Inclusion criteria for the study are: isolated AV stenosis with, reduced LV RF, low transaortic pressure gradient. Severity of AS was identified based on dobutamine stress echocardiography and aortic valve area (AVA). Severe stenosis was defined as AVA&lt; 1 cm2.Result. A statistically significant and high negative correlation was found between the AVA and AT/ET ratio, (r = 0.77, p &lt; 0.001) and weak correlation with the AT indicator (r = 0.41, p = 0.01). The RoC-analysis showed the greatest predictive ability in the differential diagnosis of severe AS for the ratio AT/ET (AUC = 0.84 ± 0.54, p &lt; 0.001) and the lower predictive ability for the indicator AT (AUC = 0.63 ± 0.72, p &lt; 0.02). The optimal threshold value for determining severe AS for the AT / ET &gt; 0.32 (sensitivity of 92%, specificity of 70%), for AT &gt; 99 (sensitivity of 81%, specificity of 88%). Multiple logistic regression analysis revealed that the AT/ET ratio is the only echocardiographic parameter that has a significant impact on the differential diagnosis of severe AS in patients with reduced LV EF (OR 1.5; 95% CI 1.2–1.9, p = 0.001). There was low interobserver variability in measurements of AT score (intraclass correlation coefficient was 0.93 [95% CI, 0.80-0.97] and AT/ET ratio (intraclass correlation coefficient was 0.88 [95% CI, 0.75–0.95]).Conclusions.In patients with AS and reduced LV stroke volume the AT/ET ratio is highly sensitive and well reproducible in the diagnosis of severe AS. The AT index has a weak diagnostic ability of severe AS in that patients.The threshold value of AT/ET &gt;0.32 can diagnose severe AS with a high degree of probability in patients with reduced LV stroke volume and reduced transaortic gradients with reduced LV EF.

Exploring the Impact of Sensor Location on Seismocardiography-Derived Cardiac Time Intervals

Abstract Cardiac time intervals (CTIs) are important parameters for evaluating cardiac function and can be measured noninvasively through electrocardiography (ECG) and seismocardiography (SCG). SCG signals exhibit distinct spectrotemporal characteristics when acquired from various locations on the chest. Thus, this study aimed to explore how SCG measurement location affects the estimation of SCG-based CTIs. ECG and SCG signals were acquired from 14 healthy adults, with three accelerometers placed on the top, middle, and bottom of the sternum. A custom-built algorithm was developed to estimate heart rates (HRs) from ECG (HRECG) and SCG (HRSCG) signals. Moreover, SCG fiducial points and CTIs, including aortic valve opening and closure, R-R interval, pre-ejection period, left ventricular ejection time, and electromechanical systole, were estimated from the SCG signals at different sternal locations. The average and correlation coefficient (R2) of the CTIs and HRs derived from all three locations were compared, along with the analysis of mean differences for the CTIs and their corresponding sensor locations. The results indicated strong correlations between HRECG and HRSCG, with average R2 values of 0.9930, 0.9968, and 0.9790 for the top, middle, and bottom sternal locations, respectively. Additionally, the study demonstrated that SCG-based CTIs varied depending on the SCG measurement locations. In conclusion, these findings underscore the importance of establishing consistent protocols for reporting CTIs based on SCG. Furthermore, they call for further investigation to compare estimated CTIs with gold-standard methods like echocardiography to identify the best SCG measurement location for accurate CTI estimations.

Examining the haemodynamic repercussions of ventilator hyperinflation in elderly patients: An explanatory study

This study assessed the cardiovascular repercussions of two VHI (ventilation hyperinflation) protocols using the volume-controlled mode, one with an inspiratory pause (VHI-P) and the other without an inspiratory pause (VHI-NP), in mechanically ventilated elderly patients. The patients underwent both VHI protocols in a randomized order, and impedance cardiography was used to record cardiovascular variables. During VHI-P, the diastolic blood pressure was lower than during VHI-NP (Δ = 10%; p = 0.009). VHI-NP and VHI-P demonstrated a decrease in cardiac output (CO) during the first and third sets compared to baseline (p < 0.05; ES=0.23 and 0.29, respectively). Arterial oxygen delivery decreased simultaneously with CO compared to baseline values (p < 0.05; ES=0.22 and 0.23, respectively). Five minutes after the intervention, the systolic time ratio values were lower for VHI-P than VHI-NP (Δ = 10%; p = 0.01). Left ventricular ejection time values were consistently lower in VHI-NP compared to VHI-P (Δ = 2%; p = 0.02). In conclusion, our study shows that VHI in volume-controlled mode induces hemodynamic changes in mechanically ventilated elderly patients, albeit with a small effect size and within the normal range.

The relationship between mechanical dyssynchrony of the left ventricular myocardium and the degree of coronary artery occlusion in patients with coronary artery disease

Background. The prevalence of chronic heart failure in the world is increasing; however, it is stabilizing in developed countries. One of the reasons for this stabilization is an improvement of acute coronary syndrome treatment and revascularization. Revascularization in patients with chronic coronary syndromes without signs of the left ventricular dysfunction is less effective. One of the promising methods for assessing left ventricular dysfunction is the detection of electrical and mechanical dyssynchrony of the myocardium (DM). However, mechanical dyssynchrony of the myocardium has not been sufficiently studied in patients with coronary artery (CA) disease. The purpose was to assess the relationship between mechanical myocardial dyssynchrony and the degree of coronary artery occlusion in patients with coronary artery disease who underwent revascularization. Materials and methods. One hundred and thirty-four patients with coronary artery disease (35 with myocardial infarction and 99 with chronic coronary syndromes) who underwent coronary angiography and revascularization of coronary arteries were included in the study. According to the results of coronary angiography, patients were divided into 3 groups: 12 had unchanged CA (group 1), 17 had atherosclerotic lesions of CA without signs of occlusion (group 2), and 105 patients were with CA occlusion. Among those with CA occlusion, 10 people had an occlusion of less than 50 %, 26 patients had occlusion from 50 to 80 %, 36 had more than 80 %, and 33 patients had complete occlusion of at least one coronary artery. In all patients, parameters of mechanical DM were determined by ultrasound method. Results. In the first group, 3 patients (25 %) had mechanical DM, in the second — 4 patients (23.5 %), in the group with coronary artery occlusion, 42 patients (40 %) had mechanical DM. In the group with complete CA occlusion, mechanical DM was detected in 18 (53 %) cases. Septal to posterior wall motion delay (SPWMD) did not differ significantly in the comparison groups; however, it increased significantly to 64.8 ± 43.2 ms in patients with complete CA occlusion compared with 40.8 ± 13.1 ms in the group with unchanged CA (p &lt; 0.05). SPWMD had a significant correlation with the degree of CA occlusion (r = 0.254, p = 0.009). The interventricular mechanical delay increased significantly, to 61.3 ± 40.5 ms compared with 33.4 ± 3.4 ms in patients with unchanged CA (p &lt; 0.05). Left ventricular filling time was significantly shorter in the group with complete CA occlusion compared to the patients with incomplete CA occlusion and those with unchanged CA (47.3 ± 10.4 ms vs. 54.2 ± 5.7 ms, respectively; p &lt; 0.05). Left ventricular ejection time was not significantly different between comparison groups, but correlated significantly with the degree of CA occlusion (r = 0.241, p = 0.013). The early ventricular time deceleration, the time from the beginning of the QRS complex to the beginning of the peak systolic velocity did not differ significantly. The time to the peak systolic velocity was significantly longer in the group with complete CA occlusion (32.6 ± 8.5 ms), and had a significant correlation with the degree of CA occlusion (r = 0.26, p = 0.007). Conclusions. A third of patients with chronic coronary syndrome included in the study had DM. In the group with complete CA occlusion, the frequency of DM detection increased significantly and was diagnosed in half of cases. In patients with complete CA occlusion, DM manifested itself in a significant SPWMD, an increase in the period of pre-ejection into the aorta and, as a result, a significant increase in the interventricular mechanical delay. An increase in the time to peak systolic velocity was also found in the group of patients with complete CA occlusion. DM associated with left ventricular diastolic dysfunction was detected in a group of patients with complete CA occlusion and manifested itself in a reduced left ventricular filling time.

Transcutaneous auricular Vagus Nerve Stimulation and Median Nerve Stimulation reduce acute stress in young healthy adults: a single-blind sham-controlled crossover study.

Stress is a major determinant of health and wellbeing. Conventional stress management approaches do not account for the daily-living acute changes in stress that affect quality of life. The combination of physiological monitoring and non-invasive Peripheral Nerve Stimulation (PNS) represents a promising technological approach to quantify stress-induced physiological manifestations and reduce stress during everyday life. This study aimed to evaluate the effectiveness of three well-established transcutaneous PNS modalities in reducing physiological manifestations of stress compared to a sham: auricular and cervical Vagus Nerve Stimulation (taVNS and tcVNS), and Median Nerve Stimulation (tMNS). Using a single-blind sham-controlled crossover study with four visits, we compared the stress mitigation effectiveness of taVNS, tcVNS, and tMNS, quantified through physiological markers derived from five physiological signals peripherally measured on 19 young healthy volunteers. Participants underwent three acute mental and physiological stressors while receiving stimulation. Blinding effectiveness was assessed via subjective survey. taVNS and tMNS relative to sham resulted in significant changes that suggest a reduction in sympathetic outflow following the acute stressors: Left Ventricular Ejection Time Index (LVETI) shortening (tMNS: p = 0.007, taVNS: p = 0.015) and Pre-Ejection Period (PEP)-to-LVET ratio (PEP/LVET) increase (tMNS: p = 0.044, taVNS: p = 0.029). tMNS relative to sham also reduced Pulse Pressure (PP; p = 0.032) and tonic EDA activity (tonicMean; p = 0.025). The nonsignificant blinding survey results suggest these effects were not influenced by placebo. taVNS and tMNS effectively reduced stress-induced sympathetic arousal in wearable-compatible physiological signals, motivating their future use in novel personalized stress therapies to improve quality of life.

Myocardial Work in Middle-Aged Adults with Overweight and Obesity: Associations with Sex and Central Arterial Stiffness.

We explored global myocardial work index (GWI), a novel measure of myocardial function that integrates left ventricular (LV) hemodynamic load, in relation to sex and increased body mass index (BMI). We used data from 467 individuals (61% women, average age 47 ± 9 years and BMI 31.2 kg/m2) without known cardiac disease. Central arterial function was analysed by applanation tonometry. GWI was calculated from global longitudinal strain (GLS) and post-echocardiography supine blood pressure (BP). Covariables of GWI were identified in linear regression analyses. Women had higher BMI, aortic augmentation pressure (12 ± 7 vs. 8 ± 6 mmHg), LV GLS (20.0 ± 2.8 vs. 18.8 ± 2.8%), and GWI (2126 ± 385 vs. 2047 ± 389 mmHg%) than men (all p < 0.05). In univariable analyses, higher GWI was associated with female sex, higher age, systolic BP, LV wall stress, LV ejection fraction, left atrial size, LV ejection time, and with lower waist circumference (all p < 0.05). In multivariable analysis, adjusting for these correlates, female sex remained independently associated with higher GWI (β = 0.13, p = 0.007). After additional adjustment for aortic augmentation pressure or central pulse pressure, this association became non-significant. In conclusion, the higher GWI in women compared to men was mainly explained by increased LV workload due to higher aortic augmentation pressure in women.

Can yoga show better vascular outcomes than regular exercise among office workers: a scoping review

Background: Isolated systolic hypertension (ISH) in the elderly is mostly brought on by arterial stiffness with ageing, which results in a lack of vascular compliance. The main cardiovascular (CV) hazards for elderly persons are arterial ageing and high blood pressure (BP). The aim of this study was to investigate if endothelial function in young, middle-aged, and older, healthy persons would be improved by Bikram yoga, a heated form of hatha yoga. Methods: Randomised control trials on yoga, vascular function, exercise, and office employees were used in the study, which was done in four databases (Scopus, PubMed, Ovid, and Science Direct). Results:  3 of 103 articles were included. We identified improvement of vascular function, FMD and arterial stiffness using yoga intervention. While exercise does not significantly affect ventricular function, yoga significantly reduces heart rate (p = 0.031) and increases pulse pressure (PD). Yoga also results in a mean increase in left ventricular ejection time (LVET), which was observed in the yoga group. The improvement in myocardial function was more pronounced in the yoga group than in the exercise group, according to the between-group analysis, which revealed a significant difference in post-intervention rate-pressure product (RPP) between the yoga and exercise groups. With a P value of 0.004, the mean% Mean Arterial Pressure (MAP) was significantly lower, demonstrating that yoga was effective in lowering MAP. However, older adults, but not younger ones, experienced a significant increase in brachial artery FMD (Flow Mediated Dilation) following the intervention. Conclusions:  Yoga interventions may improve vascular function, arterial stiffness, flow-mediated dilation, heart rate, RRP and MAP, with older adults experiencing a significant increase in brachial artery FMD, suggesting the effectiveness of yoga in improving myocardial function and lowering MAP, particularly in older adults.

Age- and sex-based normal reference ranges of the cardiac time intervals: the Copenhagen City Heart Study.

Color tissue Doppler imaging (TDI) M-mode can be used to measure the cardiac time intervals including the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT), and the combination of all the cardiac time intervals in the myocardial performance index (MPI) defined as [(IVCT + IVRT)/LVET]. The aim of this study was to establish normal age- and sex-based reference ranges for the cardiac time intervals. A total of 1969 participants free of cardiovascular diseases and risk factors from the general population with limited age range underwent an echocardiographic examination including TDI. The median age was 46years (25th-75th percentile: 33-58years), and 61.5% were females. In the entire study population, the IVCT was observed to be 40 ± 10ms [95% prediction interval (PI) 20-59ms], the LVET 292 ± 23ms (95% PI 248-336ms), the IVRT 96 ± 19ms (95% PI 59-134ms) and MPI 0.47 ± 0.09 (95% PI 0.29-0.65). All the cardiac time intervals differed significantly between females and males. With increasing age, the IVCT increased in females, but not in males. The LVET did not change with age in both sexes, while the IVRT increased in both sexes with increasing age. Furthermore, we developed regression equations relating the heart rate to the cardiac time intervals and age- and sex-based normal reference ranges corrected for heart rate. In this study, we established normal age- and sex-based reference ranges for the cardiac time intervals. These normal reference ranges differed significantly with sex.

Fetal Echocardiographic Z Score Pilot Project: Study Design and Impact of Gestational Age and Variable Type on Reproducibility of Measurements Within and Across Investigators

Fetal echocardiography is widely available, but normative data are not robust. In this pilot study, the authors evaluated (1) the feasibility of prespecified measurements in a normal fetal echocardiogram to inform study design and (2) measurement variability to assign thresholds of clinical significance and guide analyses in larger fetal echocardiographic Z score initiatives. Images from predefined gestational age groups (16-20, >20-24, >24-28, and >28-32weeks) were retrospectively analyzed. Fetal echocardiography expert raters attended online group training and then independently analyzed 73 fetal studies (18 per age group) in a fully crossed design of 53 variables; each observer repeated measures for 12 fetuses. Kruskal-Wallis tests were used to compare measurements across centers and age groups. Coefficients of variation (CoVs) were calculated at the subject level for each measurement as the ratio of SD to mean. Intraclass correlation coefficients were used to show inter- and intrarater reliabilities. Cohen's d>0.8 was used to define clinically important differences. Measurements were plotted against gestational age, biparietal diameter, and femur length. Expert raters completed each set of measurements in a mean of 23±9 min/fetus. Missingness ranged from 0% to 29%. CoVs were similar across age groups for all variables (P<.05) except ductus arteriosus mean velocity and left ventricular ejection time, which were both higher at older gestational age. CoVs were >15% for right ventricular systolic and diastolic widths despite fair to good repeatability (intraclass correlation coefficient>0.5); ductal velocities and two-dimensional measures, left ventricular short-axis dimensions, and isovolumic times all had high CoVs and high interobserver variability despite good to excellent intraobserver agreement (intraclass correlation coefficient>0.6). CoVs did not improve when ratios (e.g., tricuspid/mitral annulus) were used instead of linear measurements. Overall, 27 variables had acceptable inter- and intraobserver repeatability, while 14 had excessive variability between readers despite good intraobserver agreement. There is considerable variability in fetal echocardiographic quantification in clinical practice that may affect the design of multicenter fetal echocardiographic Z score studies, and not all measurements may be feasible for standard normalization. As missingness was substantial, a prospective design will be needed. Data from this pilot study may aid in the calculation of sample sizes and inform thresholds for distinguishing clinically significant from statistically significant effects.

A proof-of-concept investigation of multi-modal physiological signal responses to acute mental stress

In this paper, we investigated how cardiorespiratory parameters derived from multiple modalities of physiological signals respond to acute mental stress. The novelty of our study is that it derived physiology-inspired signatures of acute mental stress by exploiting (i) cross-integration of multi-modal physiological signals, (ii) cardio-mechanical signals (i.e., the seismocardiogram (SCG) and the ballistocardiogram (BCG)), and (iii) physiological signals compatible with wearable-based sensing platforms. Experimental results from 24 healthy volunteers showed that cross-integration of multi-modal wearable-compatible physiological signals may provide effective signatures that can elucidate the collective physiological changes in response to acute mental stress. In particular, (i) the R-R interval in the electrocardiogram (ECG) and the pulse rate in the photoplethysmogram (PPG), (ii) PPG amplitude, (iii) pre-ejection period (PEP) and the ratio of PEP to left ventricular ejection time (LVET) (both of which are derived from ECG and SCG), (iv) the product of R-R interval and PEP as well as the ratio of pulse transit time (PTT) derived from SCG-PPG (or BCG-PPG) pairs to PPG amplitude, (v) pulse arrival time (PAT) derived from ECG-PPG pair and PTT, and (vi) respiratory rate may be interpreted as stress-induced acute changes in (i) heart rate, (ii) total peripheral resistance, (iii) cardiac contractility (i.e., stroke volume), (iv) cardiac output, (v) arterial blood pressure, and (vi) respiratory activity, respectively. In sum, this work illustrated the proof-of-concept of tracking acute mental stress via physiology-inspired signatures derived from multi-modal physiological signals, thereby paving the way for future efforts aimed at better quantifying acute stress responses in real-world settings.