Tissue Velocity Research Articles

Evaluation of Left Ventricular Dysfunction after Single-Chamber Pacemaker Implantation in Patients with Normal Left Ventricular Function in a Tertiary Care Institution in South India

Background: In pacemaker recipients with preserved left ventricular ejection fraction, there is scant evidence regarding the effect of single-chamber pacing on left ventricular systolic function. The objective of the study was to assess the echocardiographic progression of pacemaker patients with preserved left ventricular ejection fraction at the baseline in relation to the level of right ventricular pacing and indication for pacing. Methodology: The clinical and diagnostic data from 200 patients who had undergone pacemaker implantation during 2018–2019 were analyzed. Of 200 patients, 32 patients were not included in the study in view of their baseline ejection fraction being <55% in 22 patients, loss to follow-up in six patients, and owing to four patients dying during the study. At admission and after a year of follow-up, the patient’s biodata, indications for pacemaker insertion, pacing percentage and echocardiographic parameters, and treatment profile were recorded. Results: A total of 168 patients (48.2% of males and 51.8% of females) were implanted with single-chamber permanent pacemaker. By 1 year, the mean ejection fraction, which was 61.47%, had significantly dropped to 50%. Mitral annular tissue velocity diastolic (E/e′) increased significantly (>4%) after 1 year compared to the baseline. By 1 year, there has been a significant (>10%) change from the baseline in the transannular plane systolic excursion parameter. The left ventricular systolic dysfunction happened in a greater degree in patients with advanced conduction disease compared to those who had sinus node dysfunction. Conclusion: Clinically significant left ventricle dysfunction and right ventricle dysfunction developed in a large number of pacemaker recipients with normal left ventricular function at the baseline.

The E/e' ratio on echocardiography as an independent predictor of the improvement of left ventricular contraction in patients with heart failure with reduced ejection fraction.

Clinical feature of heart failure with improved ejection fraction (HFimpEF) remains to be fully elucidated. The present study investigated the association of clinical and echocardiographic parameters with the subsequent improvement of left ventricular ejection fraction (LVEF) in heart failure with reduced ejection fraction (HFrEF). From outpatients with a history of hospitalized for heart failure, 128 subjects diagnosed as HFrEF (LVEF <40%) on heart failure hospitalization were enrolled and longitudinally surveyed. During follow-up periods more than 1 year, 58 and 42 patients were identified as HFimpEF (improved LVEF to ≥40% and its increase of ≥10 points) and persistent HFrEF, respectively. There was no difference in age or sex between the two groups with HFimpEF and persistent HFrEF. The rate of ischemic heart disease was lower and that of tachyarrhythmia was higher in the HFimpEF group than in the persistent HFrEF group. At baseline (i.e., on heart failure hospitalization), LVEF did not differ between the two groups, but left ventricular systolic and diastolic diameters were already smaller and the ratio of early diastolic transmitral velocity to early diastolic tissue velocity (E/e') was lower in the HFimpEF group. A multiple logistic regression analysis revealed that lower baseline E/e' was a significant determinant of HFimpEF, independently of confounding factors such as ischemic heart disease, tachyarrhythmia, and baseline left ventricular dimension. Our findings indicate that the lower ratio of E/e' in the acute phase of heart failure onset is an independent predictor of the subsequent improvement of LVEF in HFrEF patients.

Retrospective Ultrasound Doppler Quantification Using a Single Acquisition in Healthy Adults

Using an experimental tool for retrospective ultrasound Doppler quantification-with high temporal resolution and large spatial coverage-simultaneous flow and tissue measurements were obtained. We compared and validated these experimental values against conventional measurements to determine if the experimental acquisition produced trustworthy tissue and flow velocities. We included 21 healthy volunteers. The only exclusion criterion was the presence of an irregular heartbeat. Two ultrasound examinations were performed for each participant, one using conventional and one using experimental acquisition. The experimental acquisition used multiple plane wave emissions combined with electrocardiography stitching to obtain continuous data with over 3500 frames per second. With two recordings covering a biplane apical view of the left ventricle, we retrospectively extracted selected flow and tissue velocities. Flow and tissue velocities were compared between the two acquisitions. Statistical testing showed a small but significant difference. We also exemplified the possibility of extracting spectral tissue Doppler from different sample volumes in the myocardium within the imaging sector, showing a decrease in the velocities from the base to the apex. This study demonstrates the feasibility of simultaneous, retrospective spectral and color Doppler of both tissue and flow from an experimental acquisition covering a full sector width. The measurements were significantly different between the two acquisitions but were still comparable, as the biases were small compared to clinical practice, and the two acquisitions were not done simultaneously. The experimental acquisition also enabled the study of deformation by simultaneous spectral velocity traces from all regions of the image sector.

Discovering HFpEF in symptomatic and asymptomatic elderly outpatients to prevent hospital admission.

Transthoracic echocardiography plays an important role as an imaging tool for the evaluation of heart failure with preserved ejection fraction (HFpEF). Among the imaging findings, the E/e' ratio, a surrogate for left atrial (LA) filling pressure, is a robust indicator that supports the diagnosis of HFpEF. Other findings such as left ventricular (LV) early diastolic tissue velocity (e'), LA volume, LA strain and LV global longitudinal strain are also related to LA filling pressure, and these parameters are useful for the diagnosis of HFpEF. Although some patients with HFpEF do not have abnormalities in these indices at rest, they may develop abnormalities in LA filling pressure exclusively during exercise.1 Therefore, HFpEF is difficult to diagnose in symptomatic elderly outpatients with limited exercise capacity (Figure 1). There are two types of probability tests in which HFpEF is present in patients with dyspnoea based on the findings obtained in clinical settings: the H2FPEF score2 and the HFA-PEFF score.3 Although both scores included echocardiographic indices, the H2FPEF score focuses on comorbidities, whereas the HFA-PEFF score includes natriuretic peptide levels. Most patients with HFpEF have a history of hypertension, and their blood pressure levels may no longer be elevated by medications at the time of evaluation.4 Furthermore, most patients with HFpEF show a high BMI, which is not the case in older patients.5 Because natriuretic peptide levels are occasionally within normal limits in patients with HFpEF, they may not be necessary for the diagnosis of HFpEF.2 Haemodynamic exercise tests play a key role when one cannot make a definitive decision of developing HFpEF. Noninvasive exercise testing does not discriminate between patients with cardiac and non-cardiac causes of dyspnoea.6 Although exercise echocardiography is a useful tool in place of invasive stress testing, there are contradictory results regarding the significance of the E/e' ratio for LA filling pressure.7, 8 Since LV diastolic function is affected by afterload, we recently evaluated LV diastolic function as a vascular resistance-integrated index: the ratio of LV diastolic elastance (Ed) to arterial elastance (Ea) = (E/e')/(0.9 × systolic blood pressure).9 This noninvasive index shows the ratio of LA filling pressure to LV end-systolic pressure and is a significant index of all-cause mortality in a multivariate Cox proportional hazards regression analysis performed by adjusting for age, comorbidities, natriuretic peptide levels and echocardiographic indices in elderly patients with HFpEF.10, 11 Stress tests cause an elevation of systolic blood pressure, and the extent of the change in blood pressure is different in each patient. Using an index such as Ed/Ea, the conflicting consequences described above may disappear. For the diagnosis of heart failure (HF), patients are aware of certain symptoms such as exertional dyspnoea, chest discomfort and fatigue. However, the symptoms are sometimes obscured in older patients. In clinical settings, it is important to identify patients with latent HFpEF who will likely be admitted for HF treatment in the near future. When populations with asymptomatic hypertension undergo invasive exercise stress or exercise echocardiography, some portions may exhibit an elevated LA filling pressure during exercise. We may call these populations ‘pre-HFpEF’ patients in terms of clinical entity.12 Asymptomatic LV hypertrophy is a potent risk factor for HFpEF.13 The main pathologies of HFpEF include cardiomyocyte remodelling and interstitial collagen deposition resulting from endothelial dysfunction and microvascular inflammatory changes.14-16 These latent populations might have treatment as ‘pre-HFpEF’ to avoid admission for HF. The diagnosis and treatment of asymptomatic elderly outpatients without a history of admission for HF, who possibly show exercise-induced elevation of LA filling pressure, remain to be defined. Recently, emerging differences in the phenotyping of HFpEF have been shown.17, 18 Asymptomatic patients with certain phenotypes must undergo stress echocardiography to diagnose pre-HFpEF. Under these conditions, the measurement of the Ed/Ea ratio may play a key role in the discrimination of several phenotypes in a multivariate model. As the medications and prognosis for HFpEF may be different from its phenotype,19, 20 it is urgent to elucidate the type of HFpEF or pre-HFpEF that should be medicated according to treatment type to reduce the incidence of admission for HF and mortality in the era of a super-ageing society. Among elderly clinic patients, we must detect symptomatic outpatients with possible HFpEF as well as asymptomatic ‘pre-HFpEF’ outpatients to reduce admission for HF in the near future and to conserve resources in the era of a super-ageing society. A vascular resistance-integrated LV diastolic index, (E/e')/(0.9 × systolic blood pressure), may play a role in revealing these patients in addition to possible comorbidities. None. No funding was received in relation to this article.

Normal range of intraoperative three-dimensionally derived right ventricular free-wall strain in coronary artery bypass surgery patients.

Data on intraoperative three-dimensionally derived right ventricular free-wall strain (3D-RV FWS) is sparse. We sought to evaluate the normal range of intraoperative 3D-RV FWS in patients scheduled for coronary artery bypass graft (CABG) surgery and compared to conventional echocardiographic parameters. Prospective observational study. A total of 150 patients with preserved left and right ventricular (RV) function and sinus rhythm, without significant heart valve disease or pulmonary hypertension undergoing isolated on-pump CABG surgery, with an uneventful, complication-free intraoperative course. 3D-RV FWS analysis and conventional echocardiographic assessment of RV function were performed intraoperatively in anesthetized and ventilated patients using transesophageal echocardiography (TEE). TomTec 4D RV-Function 2.0 software for assessment of 3D-RV FWS and three-dimensional right ventricular ejection fraction (3D-RV EF). Philips QLAB 10.8 was used to evaluate tissue velocity of the tricuspid annulus (RV S´), tricuspid annular systolic excursion (TAPSE), and RV fractional area change (FAC). All echocardiographic measurements were performed under stable hemodynamic conditions and predefined fluid management without any vasoactive support or pacing. The prospective observational study was performed in a single university hospital setting. Assessment of 3D-RV FWS was feasible in 95% of patients. No included patient experienced any serious perioperative complication. In our group of patients, median values with interquartile range (IQR) for 3D-RV FWS and 3D-RV EF were -25.2 (IQR -29.9 to -21.8) and 46.3% (IQR 41.0%-50.1%), respectively. RV FAC, RV S´, and TAPSE accounted for 39.7% (IQR 34.5%-44.4%), 14.8cm/s (IQR 11.8-19.0cm/s), and 22mm (IQR 20-25mm). The normal range (2.5% to 97.5% percentile) for 3D-RV FWS was -37.1 to -12.8. There was no relevant correlation of 3D-RV FWS to postoperative outcome in this group of CABG patients. We present distribution values for intraoperative 3D-RV FWS and conventional parameters of RV function assessment in a healthy on-pump CABG patient population without serious perioperative complications. We observed no correlations of these parameters with any of the outcome parameters considered. Therefore, we consider these values to be intraoperative TEE-assessed normal values, which can be expected in on-pump CABG patients.

A fast blind source separation algorithm for decomposing ultrafast ultrasound images into spatiotemporal muscle unit kinematics

Objective. Ultrasound can detect individual motor unit (MU) activity during voluntary isometric contractions based on their subtle axial displacements. The detection pipeline, currently performed offline, is based on displacement velocity images and identifying the subtle axial displacements. This identification can preferably be made through a blind source separation (BSS) algorithm with the feasibility of translating the pipeline from offline to online. However, the question remains how to reduce the computational time for the BSS algorithm, which includes demixing tissue velocities from many different sources, e.g. the active MU displacements, arterial pulsations, bones, connective tissue, and noise. Approach. This study proposes a fast velocity-based BSS (velBSS) algorithm suitable for online purposes that decomposes velocity images from low-force voluntary isometric contractions into spatiotemporal components associated with single MU activities. The proposed algorithm will be compared against spatiotemporal independent component analysis (stICA), i.e. the method used in previous papers, for various subjects, ultrasound- and EMG systems, where the latter acts as MU reference recordings. Main results. We found that the computational time for velBSS was at least 20 times less than for stICA, while the twitch responses and spatial maps extracted from stICA and velBSS for the same MU reference were highly correlated (0.96 ± 0.05 and 0.81 ± 0.13). Significance. The present algorithm (velBSS) is computationally much faster than the currently available method (stICA) while maintaining the same performance. It provides a promising translation towards an online pipeline and will be important in the continued development of this research field of functional neuromuscular imaging.

PO-04-052 FLECAINIDE INDUCED WIDE COMPLEX TACHYCARDIA

Flecainide is a class IC antiarrhythmic that blocks cardiac sodium channels and is used to treat a variety of supraventricular tachyarrhythmias. Flecainide has use dependent properties with a greater effect at higher heart rates and carries a risk of atrial flutter with 1:1 AV conduction, Describing a case of wide complex tachycardia secondary to flecainide use. N/A A 72-year-old female with COPD, diabetes, history of typical atrial flutter, and persistent atrial fibrillation treated with flecainide and diltiazem called EMS when she awoke with sudden onset dyspnea and epigastric pain. EMS found her diaphoretic, tachycardic, and normotensive. EKG showed a wide complex tachycardia (WCT) with rate 230 bpm. She received an amiodarone bolus but remained in WCT. In the ER, she became hypotensive and was electrically cardioverted to sinus rhythm with resolution of dyspnea and hypotension. She was started on heparin and amiodarone drips. Troponin peaked at 0.04 ng/mL. A coronary angiogram showed no significant coronary artery disease and a transthoracic echocardiogram showed ejection fraction 60-65% with normal wall motion. However, a prior EKG on flecainide was reviewed and demonstrated atrial flutter with a 2:1 AV conduction and an atrial rate of 230 bpm. The WCT was most likely due to atrial flutter with 1:1 AV conduction and aberrancy. Flecainide slows conduction velocity in myocardial tissue, increasing the cycle length of the flutter circuit, and this can allow for 1:1 AV conduction with atrial flutter. Flecainide also demonstrates use dependent properties, with more sodium blocking effect at higher heart rates, and this can cause QRS widening in the setting of tachycardia. Although flecainide is also reported to cause ventricular tachycardia, the patient’s heart rate was exactly the same as a prior atrial rate in atrial flutter, so this was felt to be atrial flutter with 1:1 conduction and aberrancy. The patient’s flecainide and diltiazem were discontinued, and she was started on amiodarone. Medications should be reviewed as a possible cause of WCT after structural and ischemic causes are ruled out. While not a common cause of WCT, flecainide can organize atrial fibrillation into atrial flutter, which could result in 1:1 AV conduction, aberrancy, and wide complex tachycardia.

PO-05-019 WHEN RIGHT IS WRONG: INCIDENCE AND OUTCOMES OF RIGHT BUNDLE BRANCH BLOCK FOLLOWING TRANSCATHETER AORTIC VALVE REPLACEMENT

Right bundle branch block (RBBB) following transcatheter aortic valve replacement (TAVR) for aortic stenosis is uncommon. However, its incidence and prognosis have not been well-described. To characterize the incidence of post-TAVR RBBB alongside its associated risk of permanent pacemaker (PPM) implantation and mortality. All patients ≥18 years who underwent TAVR at the Mayo Clinic Enterprise from June 2010 to May 2021 were considered; patients with pre-TAVR RBBB and/or PPM were excluded from the analysis. Clinical history, imaging variables, and electrocardiographic data were abstracted from the electronic medical records. Post-TAVR RBBB, defined as new onset RBBB in the postprocedure period, was manually verified by the study authors. The risks of PPM implantation (within 90-days post-TAVR) and mortality following TAVR were compared between patients with and without post-TAVR RBBB using the Kaplan-Meier method and Cox proportional hazards modeling. Out of 1992 patients included, 15 (0.75%) experienced new RBBB post-TAVR. There was a higher proportion of patients who had valve oversizing among patients with new RBBB post-TAVR versus not (17.9% versus 10.0%, p=0.034). There were no other significant differences in demographics or clinical characteristics between patients with and without post-TAVR RBBB including age at TAVR, sex, type of valve implanted, valve size, aortic valve calcium score, or left ventricular ejection fraction (Table 1). Ten patients (66.7%) with post-TAVR RBBB experienced high-grade atrioventricular block (≥2 consecutive blocked P waves) and subsequently underwent PPM implantation (median 4 days; interquartile range 1-90 days), compared to 268/1977 (13.6%) without RBBB (Figure 1). After adjustment for age, sex, balloon expandable valve, annulus diameter, and valve oversizing, post-TAVR RBBB was significantly associated with PPM implantation (hazard ratio [HR] 8.36, 95% confidence interval [CI] 4.19-16.7; p<0.001). No statistically significant increase in mortality was seen with post-TAVR RBBB (HR 0.83, 95% CI 0.33-2.11; p=0.69) following adjustment for age and sex. Although encountered rarely, post-TAVR RBBB was associated with an elevated risk of PPM implantation. The mechanisms for its development and its clinical prognosis require further study.Tabled 1Table 1: Baseline characteristics of study cohortMedian (IQR) or No. (%) of patientsVariableNNo RBBB (N=1977)New-Onset RBBB (N=15)P-valueAge at TAVR1,99281.3 (75.4, 86.0)82.6 (78.8, 87.4)0.45Sex (Males)1,9921,111 (56.2%)9 (60.0%)0.80Balloon Expandable Valve1,9921,744 (88.2%)12 (80.0%)0.41Valve size1,99226.0 (23.0, 29.0)26.0 (24.5, 29.0)0.49Annulus Area (cmˆ2) based on CT1,8504.7 (4.0, 5.4)4.6 (4.3, 5.1)0.81Annulus Diameter (mm)1,93027.0 (25.0, 29.1)26.0 (25.1, 28.8)0.87Valve Oversizing *1,85010.0 (3.0, 18.5)17.9 (15.4, 23.4)0.034LVEF (%)1,89762.0 (55.0, 66.0)61.5 (54.2, 67.8)0.97AV Peak Velocity1,8974.2 (4.0, 4.6)4.1 (4.0, 4.3)0.42AV Mean Gradient1,89743.0 (38.0, 51.0)41.5 (41.0, 44.8)0.76AV Area1,8970.8 (0.7, 0.9)0.9 (0.8, 1.0)0.33LVOT AV Velocity Ratio1,8970.2 (0.2, 0.2)0.2 (0.2, 0.3)0.47LVOT AV TVI Ratio1,8970.2 (0.2, 0.2)0.2 (0.2, 0.3)0.51LVOT Dimension1,7292.2 (2.1, 2.3)2.2 (2.1, 2.3)0.77LV Geometry9710.64Concentric Hypertrophy359 (37.4%)5 (45.5%)Concentric Remodeling264 (27.5%)2 (18.2%)Eccentric Hypertrophy158 (16.5%)3 (27.3%)Normal Geometry179 (18.6%)1 (9.1%)LVED Dimension1,55649.0 (45.0, 53.0)48.0 (43.0, 53.5)0.64Aortic Valve Calcium Score1,7302,281.0 (1,556.5, 3,169.5)2,729.0 (1,979.1, 3,480.5)0.31Myocardial Infarct1,987137 (6.9%)2 (13.3%)0.28Congestive Heart Failure1,987522 (26.5%)5 (33.3%)0.56Charlson Comorbidity Index1,9872.0 (0.0, 4.0)2.0 (1.0, 4.0)0.61STS Risk Score1,7304.8 (3.0, 8.0)4.0 (3.1, 9.2)0.86P-values result from a Wilcoxon rank sum test (continuous variables) or Fisher’s exact test (categorical variables). *Valve oversizing = (Nominal Area / Annulus area (mm)) -1) *100 AV – aortic valve; CT – computed tomography; IQR – interquartile range; LVEF – left ventricular ejection fraction; LVOT – left ventricular outflow tract; STS – Society of Thoracic Surgeons; TAVR – transcatheter aortic valve replacement; TVI - tissue velocity index Open table in a new tab

Assessment of Left Ventricular Functions by Two-Dimensional Speckle Tracking Echocardiography in Patients with Coronary Slow-Flow Phenomenon.

Background: Coronary slow flow phenomenon (CSFP) is a medical challenge, especially regarding its diagnosis. The use of speckle tracking seems to provide a clue for diagnosis. However, its role is not well addressed.&#x0D; Aim of the work: To assess the value of the left ventricle's global longitudinal strain by 2D speckle tracking to detect subclinical left ventricular systolic dysfunction in patients with the slow coronary flow.&#x0D; Patients and methods: This study was performed between May and September 2020 at the cardiology department, Al-Azhar University Hospital (New Damietta). Thirty patients are known to have slow coronary flow based on a previous coronary angiographic examination, and 30 healthy participants with the same demographic match (age and sex) as a control group were included. Patients were classified into two groups: Group (A): Included 30 patients with a coronary slow flow. Group (B): Included 30 normal healthy adult persons served as a control group. All were assessed clinically and by radiological investigations. In addition, speckle tracking echocardiography was done for all patients.&#x0D; Results: In Doppler flow measures, E wave and E/A ratio showed significantly lower values in CSFP when compared with the control group (p= 0.02, 0.003 respectively). According to tissue velocity imaging (TVI), there is a similarity between both groups without any significant difference. Speckle tracking measurements demonstrate significantly lower value in patients with CSFP than the control group (p=0.003).&#x0D; Conclusion: In patients with CSF, LV systolic function detected during both conventional and tissue Doppler echocardiographic examinations was not affected, but 2D longitudinal strain demonstrated that LV systolic function was impaired. CSFP could impair LV diastolic function.

MATHEMATICAL DESCRIPTION OF A BLEACH IMPREGNATION RESERVOIR

This article discusses the issues of constructing a mathematical model of the technological process of bleaching textile materials in an impregnating reservoir using the heat balance equation, on the basis of which a qualitative analysis of the dynamic properties of an object has been carried out in order to create highly efficient control systems with the use of energy-saving technologies. While constructing a mathematical model characterizing the established and non-established modes of the control object (impregnating reservoir) used changes in heat flow and mass velocity of the incoming tissue. An algorithm for constructing a mathematical model of the process of bleaching cotton fabrics has been proposed. The results of solving a practical problem show the adequacy of the developed model.

Dynamic evolution and mechanism of myocardial glucose metabolism in different functional phenotypes of diabetic cardiomyopathy — a study based on 18 F-FDG microPET myocardial metabolic imaging

PurposeTo use 18 F-FDG microPET dynamic imaging to preliminarily identify the changes of myocardial glucose metabolism corresponding to different functional phenotypes of diabetic cardiomyopathy (DCM) in mice and elucidate their relationships.MethodsLeft ventricular function was measured by echocardiography in C57BL/KsJ-db/db (db/db) mice and their controls at 8, 12, 16, and 20 weeks of age to divide DCM stages and functional phenotypes. Myocardial histopathology was used to verify the staging accuracy and list-mode microPET dynamic imaging was conducted. The myocardial metabolic rate of glucose (MRglu) and the glucose uptake rate constant (Ki) were derived via Patlak graphical analysis, and the differences in myocardial glucose metabolism levels in different DCM stages were compared. The key proteins involved in myocardial glucose metabolism signaling pathway were analyzed by Western blotting to elucidate the underlying mechanism of abnormal glucose metabolism in DCM.ResultsCompared with the controls, the ratio of early diastolic transmitral flow velocity to early diastolic mitral annular tissue velocity (E/e’) of db/db mice was significantly increased from the age of 12 weeks, while the left ventricular ejection fraction (LVEF) was significantly decreased from the age of 16 weeks (all P < 0.05). Based on the staging criteria, 8 and 12 weeks (8/12w) db/db mice were in DCM stage 1 (diastolic dysfunction with normal LVEF), and 16 and 20 weeks (16/20w) db/db mice were in DCM stage 2/3 (diastolic and systolic dysfunction). The degree of myocardial fibrosis, glycogen deposition and ultrastructural damage in 16/20w db/db mice were more obvious than those in 8/12w group. The myocardial MRglu, Ki of db/db mice in 8/12w group or 16/20w group were significantly lower than those in the control group (all P < 0.05), while the myocardial standard uptake value (SUV) was not significantly reduced in the 8/12w group compared with the control group (P > 0.05). MRglu and SUV were moderately negatively correlated with the E/e’ ratio (r=-0.539 and − 0.512, P = 0.007 and 0.011), which were not significantly correlated with LVEF (P > 0.05). Meanwhile, Ki was not significantly correlated with LVEF or E/e’ ratio. The decreased expression of glucose transporter (GLUT) -4 in db/db mice preceded GLUT-1 and was accompanied by decreased phosphorylated AMP-activated protein kinase (p-AMPK) expression. Myocardial MRglu, Ki and SUV were significantly positively correlated with the expression of GLUT-4 (MRglu: r = 0.537; Ki: r = 0.818; SUV: r = 0.491; P = 0.000 ~ 0.046), but there was no significant correlation with GLUT-1 expression (P = 0.238 ~ 0.780).ConclusionsDuring the progression of DCM, with the changes of left ventricular functional phenotype, abnormal and dynamic changes of myocardial glucose metabolism can occur in the early stage.

Changes in Myocardial Tissue Velocities over a Decade: The Copenhagen City Heart Study

Changes in Myocardial Tissue Velocities over a Decade: The Copenhagen City Heart Study

Changes in cardiac function in Navy divers during four days of successive dives in very cold diving conditions.

There is limited knowledge of cumulative effect of repetitive cold-water diving on cardiac function. Single cold dives cause some known cardiological risks, such as malign arrhythmia, due to a concurrent activation of the sympathetic and parasympathetic autonomic nervous system. A previous study from warmer water dives has shown that successive dives cause a decrease in vagal tone and a less responsive cardiovascular system. The aim of this study was to evaluate changes in cardiac function with 2D echocardiography during 4 days of diving in near-freezing water. Left ventricle systolic function measures did not show any uniform changes. E/A ratio seemed to decrease successively with the number of dives. The diastolic tissue velocity of relaxing basal septum (e') showed a decreasing trend as well. Diastolic blood pressure seemed to increase from predive (mean: 83 RR mmHg) to postdive values (mean: 87 RR mmHg) (p=NS). Heart rate decreased significantly from predive (mean: 71 bpm, range: 56-103) to postdive values (mean: 60 bpm, range: 37-88) (p < 0.03). The study was conducted in very cold condition and with limited number of divers. Results of this preliminary study suggested a decreasing trend in left ventricular diastolic function in successive cold dives. Cumulative changes in cardiac function may cause health risks that need to be considered during cold water diving operations.

The evaluation of vascular flow in clubfoot: a resistive index and peak systolic velocity study.

Resistive index (RI) and peak systolic velocity (PSV) are important Color doppler ultrasonography (CDU) parameters indicating the microcirculation and flow velocity in tissues. We aim to determine the changes in vascular flow characteristics in clubfoot after Ponseti treatment. There were three groups: the clubfoot group, the healthy group (the unaffected feet with unilateral deformities) and the control group. The Pirani severity scoring and CDU examinations of the foot were performed at initial admission and the 6th-month follow-up after Ponseti treatment. A total of 34 feet of 24 patients were included in the study. The mean age at initial treatment was 20.9 ± 22.5 days. The RI and PSV values of the clubfeet and the healthy group were similar. Resistive index values were significantly lower, and PSV values were significantly higher in the control group. After Ponseti treatment, only RI of the dorsalis pedis artery decreased, but PSV increased for all of the arteries. Recurrence of the deformity deteriorates the improvement in vascular development. Resistive index and PSV values were not related to the initial severity of the deformity. The RI values were higher, and PSV values were lower in clubfoot patients compared with the normal control group. Vascular pathology is a component of clubfoot, and treatment success improves vascular development. The improvement of microcirculation and blood flow velocity together was detected only in the dorsalis pedis artery. The effect of vascular flow change on prognosis was not detected.

Sound Velocity and Equation of State of Ballistic Gelatin by Brillouin Scattering.

Brillouin scattering spectroscopy with diamond anvil cells was used by measuring the pressure dependence of the sound-relevant polymer material, glass-forming liquid, and H2O (water and ice VII) velocities of the material from ambient pressure to 12 GPa at room temperature. Measurements of 20%, 10%, and 4% gelatin solutions were performed. For comparison purposes, we also measured the pressure dependence of the sound velocity of animal tissue up to 10 GPa. We analyzed the Brillouin data using the Tait and Vinet equations of state. We discussed the possible influence of frequency dispersion on bulk modulus at low pressure. We compared the elastic moduli obtained for gelatin to those of several other polymers.

Influence of non-apical permanent pacing on left ventricular systolic impairment

Abstract Funding Acknowledgements Type of funding sources: None. Background Right ventricular apical (RVA) pacing deleterious effects on left ventricular ejection fraction (LVEF) had been demonstrated. Non-apical pacing, such as right ventricular mid-septal (RVMS) and His Bundle pacing, appear as practical alternatives. Our purpose is to evaluate the effect of alternate sites of right ventricular (RV) pacing on left ventricular (LV) function and hemodynamics in patients with bradyarrhythmias. Methods We observed 118 patients (age 58±27 years, 64% men) with AV block III, who underwent permanent dual chamber pacemaker implantation. To 72 patients RV lead has implanted the middle area of RV septum (RVMS) and 46 patients’ RV lead has been implanted traditionally to the right ventricular apex (RVA). Color tissue velocity imaging was performed to analyze time to peak systolic velocity (Ts) in a 12 segment model of the LV for each pacing site. Measurements included standard deviation of time to peak systolic velocity (SD-Ts) for all segments, the maximal difference in Ts between any 2/6 basal (Ts-B), any 2/6 mid segments (Ts-M) and maximal Ts difference between any 2/12 segments (Ts-12). Stroke volume was estimated using Doppler velocity time integral (TVI) in the left ventricular outflow tract (LVOT). QRS width for each site was recorded. Measurements were observed by transthoracic echocardiography and electrocardiography before and 12 months after implantation. Results Ts-12 was significantly higher with RVA - pacing (107 ms, p=0.003) compared to RVMS - pacing (81 ms) sites. SD-Ts were significantly higher with RVA - pacing (38.5 ms, p=0.01) than RVMS - pacing (28.7 ms). QRS duration was the longest for RVA - pacing (157 ms) while significantly shorter RVMS - pacing (115 ms, p&amp;lt;0.001). LVOT VTI was significantly higher for RVMS - pacing than for RVA (p=0.0014) pacing. Conclusions Right ventricular mid-septal pacing may reduce electro-mechanical dyssynchrony compared to RVA pacing and RVMS – pacing to effect better LV function and hemodynamics than RVA pacing in patients with permanent pacemaker implantation.

Utility of E/e′ Ratio During Low-Level Exercise to Diagnose Heart Failure With Preserved Ejection Fraction

BackgroundE/e′ ratio during exercise is the key parameter in identifying elevated pulmonary capillary wedge pressure (PCWP), and thus heart failure with preserved ejection fraction (HFpEF). However, its diagnostic value is limited when mitral inflow or tissue velocities are fused during elevated heart rate. ObjectivesThe authors hypothesized that E/e‘ ratio during low-level (20 W) exercise (E/e′20W) can help diagnose HFpEF. MethodsErgometric exercise stress echocardiography was performed in 215 dyspneic patients with an EF ≥50%. The authors determined the feasibility of E/e′ ratio at each stage (frequency of patients who had measurable E/e′ without E-A fusion among 215 participants) and examined whether E/e′20W could predict normal E/e′ ratio during peak exercise (E/e′peak ≤15). The authors also evaluated whether E/e′20W could predict normal PCWP during exercise (PCWP <25 mm Hg) in a subset of participants (n = 45) who underwent exercise right heart catheterization. ResultsThe feasibility of the E/e′ ratio decreased from 100% at rest to 96.3% during 20-W exercise and 74.9% during peak exercise caused by E-A fusion. In patients with E/e′peak >15, there was an increase in E/e′ ratio from rest to 20-W exercise (11.2 ± 2.1 to 16.3 ± 3.5; P < 0.0001), but it did not change significantly from 20-W exercise to peak exercise (P = 0.12). E/e′20W predicted E/e′peak ≤15 (AUC: 0.91; P < 0.0001) with the cutoff value of ≤12.4 showing high specificity (94%) and positive predictive value (98%). During 20-W exercise, 93% of the HFpEF patients developed PCWP ≥25 mm Hg. E/e′20W predicted normal PCWP during exercise (AUC: 0.77; P = 0.01) with the cutoff value of ≤12.4 showing high specificity (83%). ConclusionsE/e′ ratio during low-level exercise is highly feasible and predicts normal E/e′ ratio or PCWP during peak exercise with high specificity. These data suggest that E/e′20W could be used as an alternative to the peak exercise value to rule out HFpEF in patients with dyspnea.

The predictive value of revised diastolic dysfunction in outcomes of liver transplantation: A propensity score matching analysis.

Diastolic dysfunction (DD), one of the earliest signs of cirrhotic cardiomyopathy (CCM), is included in the revised 2019 CCM criteria. Nonetheless, relevant research regarding the effects of revised DD on post-liver transplantation (LT) outcomes remains limited. This retrospective study enrolled patients who underwent LT for decompensated cirrhosis, from January 2018 to March 2021. Patients were divided into DD and non-DD groups. Clinical data were collected. Patients were followed up with, for at least 1 year post-LT; cardiovascular adverse events (AEs) and survival status were recorded. Risk factors were identified using 1:2 propensity score matching (PSM), after adjusting for confounding factors. The caliper value was set to 0.02. Of 231 patients, 153 were diagnosed with DD (male, 81.8%; mean age, 51.5 ± 9.5 years). Nineteen patients with DD died within 1 year, post-LT. After PSM, 97 and 60 patients were diagnosed with and without DD, respectively. Patients with DD had longer intensive care unit (ICU) stays, higher perioperative cardiovascular AEs, and higher mortality rates than those without DD. In a multivariate analysis, interventricular septum (IVS), left atrial volume index (LAVI), and potassium levels were independent prognostic factors of perioperative cardiovascular AEs, while a decreased early diastolic mitral annular tissue velocity (e'), increased neutrophil-to-lymphocyte ratio (NLR) and tumor markers were predictors of mortality within 1 year post-LT after PSM (P < 0.05). Cardiac DD may contribute to perioperative cardiovascular AEs and mortality post-LT. Clinicians should be aware of decompensated cirrhosis in patients with DD.

Which Type of Cardiomyopathy (Ischemic or Dilated) can be Attributed to more Alteration in Right Ventricular Dysfunction?

Background: There are few studies in the literature comparing the RV function of the two entities of dilated cardiomyopathy (DCM) and ischemic cardiomyopathy (ICM). The aim of this study was to compare RV dysfunction among patients with ICM or DCM. Methods: The study population consisted of 287 consecutive patients with heart failure referred for pre-CRT echocardiography evaluation at the Tehran Heart Center between January 2005 and December 2010. A complete transthoracic echocardiographic examination, which included 2-dimensional and Doppler echocardiography with color flow mapping were performed using standard techniques. For assessing RV function, the two parameters of the tricuspid annular plane systolic excursion (TAPSE) and right ventricular peak mean systolic tissue velocity (RVSM) were measured. Results: Comparing RV function on TAPSE measurement between the ischemic and dilated cardiomyopathy groups showed no significant differences between them that the mean of TAPSE was 15.05 ± 4.65 mm and 15.64 ± 4.90 mm, respectively. With respect to assessing RV function using peak mean systolic RVSM measurement, this parameter in the ischemic and dilated cardiomyopathy were also similar (3.795 ± 2.050 cm/s versus 4.551 ± 2.753 cm/s, p = 0.176). Conclusion: There is no difference with regard to RV functional state between ICM and DCM.

852 DAPAGLIFOZIN IN PATIENTS WITH CARDIAC HEART FAILURE

Abstract Dapaglifozin on diastolic function in patients with type 2 diabetic mellitus and chronic heart failure Heart failure (HF) with reduced ejection fraction (HFrEF) remains a challenging problem due to its high mortality rate. Another novelty in HF therapy is dapagliflozin, a sodium-glucose transporter-2 inhibitor (SGLT2i) which decreased the rates of cardiac death and worsening of HF in the DAPA-HF trial, when added in other guideline recommended therapy. Material and methods A prospective cohort study of 30 symptomatic HF patients with EF &amp;lt; 35% (aged 65 ±10 years) (20 males and 10 females) was conducted. Diabetic (2TDM) patients of NYHA status II–III, previously treated with ARNI, β-blocker, and mineralocorticoid receptor antagonists (MRA) were included. Dapagliflozin 10 mg was added as an adjunct therapy for 2TDM but also as a novel therapy of HF in diabetic patients. Clinical examination and complete echocardiographic evaluation were performed at baseline and 30 days after the addition of SGLT2i to their treatment. 2D echocardiography and Doppler measurements were used for the evaluation of left ventricular function, and more specifically, peak early (E-wave) and late (A-wave) transmitral filling velocities and their ratio E/A, deceleration time of E velocity (DTE). To classify diastolic dysfunction according to the ASE/EACVI guidelines published in 2016, transmitral E and A waves velocities, septal and lateral E’ tissue velocities, indexed left atrium volume and peak velocity of tricuspid regurgitation were collected. Results After 30 days of therapy with dapagliflozin, blood pressure was reduced significantly and the echocardiographic parameters of diastolic function were improved. More specifically, after 6.1±3.6 months of treatment E/A ratio decreased from 1.7 ±1.5 to 1.01±0.70 (P &amp;lt;0.05), the E/Ea ratio decreased from 13.5± 6.3 vs. 10.2± 5.2 (P &amp;lt;0.05), tricuspid regurgitation peak velocity decreased from 3.0±0.4 to 2.4± 0.5m/s (P =0.03) and left atrial volume decreased from 53 ±29.3 to 40.3±11.5ml/m2 (P &amp;lt;0.05). Subsequently, both left-ventricular diastolic function and filling pressure improved significantly (P &amp;lt;0.05,). Discussion Our data support the evidence that SGLT2i ameliorate both the conventional echocardiographic indexes of diastolic function and this effect is noted quite promptly. The ratio of early diastolic transmitral flow velocity seems to correlate well with LV filling pressures, and may be use das a prognostic tool in patients with HFrEF. We have to emphasize that the diastolic function improvement was observed 30 days after the initiation of dapagliflozin treatment, and thus it may be considered an early marker of improvement and adequacy of treatment apart from BNP. Conclusions in this study classical diastolic echocardiographic parameters were improved promptly after initiation of dapagliflozin therapy. The ratio of early diastolic transmitral flow velocity at the early filling phase of diastole (E/SRE) may be considered a reliable index of HF therapy responders.