Septal Segments Research Articles

Assessment of right ventricular segmental volumes and ejection fractions using a 15-segment model: three-dimensional echocardiographic study in healthy volunteers

Abstract Funding Acknowledgements Type of funding sources: None. On top of global ventricular function, segmental metrics may bear clinically relevant information. Concerning the left ventricle (LV), standardized segmentation is widely performed in different cardiovascular imaging modalities mainly to correlate regional dysfunction with coronary perfusion territories, or to appreciate and quantify distinct patterns in LV myocardial function. The same applies to the right ventricle (RV); as pulmonary hypertension, or arrhythmogenic cardiomyopathy are just two clinical examples among several others, where established regional dysfunction exists. Nevertheless, only a few options are available for the comprehensive and quantitative assessment of the segmental RV function due to its complex three-dimensional (3D) shape. Therefore, our aim was to develop a 3D echocardiographic software solution for volumetric partitioning of the RV using a 15-segment model and to investigate a large number of healthy volunteers to describe the normal segmental pattern. One hundred and fifty healthy adults with a balanced age range and an equal sex distribution were investigated (15-15 women and men in each age groups: 20-29, 30-39, 40-49, 50-59, 60+). Beyond standard two-dimensional echocardiographic protocol, full volume 3D datasets were acquired. Using commercially available software, we reconstructed the 3D mesh model of the RV and measured end-diastolic (EDV), end-systolic volumes and ejection fraction (EF). The 3D model was post-processed using the ReVISION method to calculate regional and segmental volumes and EFs. Fifteen standard segments were separated and quantified (Figure). Increasing age resulted in significantly lower RV stroke volume (r=-0.17; p < 0.05) and tended towards lower RV EDV (r=-0.15, p = 0.06). EDVs of inflow tract and outflow tract segments decreased during aging (r=-0.21, p < 0.05 and r=-0.26, p < 0.01, respectively). Between the pre-specified age groups, there was no difference concerning global RVEF (ANOVA p = NS). In the 50-59 age group, regional EF of septal segments and also free wall segments were significantly lower compared to subjects in the 30-39 and 40-49 age categories (both p < 0.05). Global RV EDV was significantly lower in women (women vs. men: 95 ± 20 vs. 125 ± 28 ml; p < 0.05) along with a higher RV EF compared to men (62 ± 4 vs. 59 ± 4; p < 0.05). However, segmental EFs of apical, septal mid anterior, free wall mid posterior, free wall mid lateral, septal basal anterior and inflow tract segments were comparable between genders. The ReVISION method allows a volumetric partitioning of the RV 3D models to investigate segmental geometry and function in a 15-segment model. We have explored segmental differences between different ages and genders. Further studies are warranted to justify the importance of segmental assessment of the RV in different cardiac diseases. Abstract Figure. Separation of 15 standard RV segments

Evolution of biventricular T1 values in patients with right-sided congenital heart disease

Abstract Funding Acknowledgements Type of funding sources: None. Background Conflicting reports exist on the prevalence and clinical impact of interstitial fibrosis in right ventricular (RV) congenital heart disease (CHD). This study evaluates the longitudinal evolution of native myocardial T1 relaxation time (T1) in RV CHD. Methods On a 1.5T scanner, an ECG-triggered modified Look-Locker inversion recovery sequence (scheme 3(3)3(3)5) was acquired on a short-axis basal slice covering the RV and left ventricle (LV) on two consecutive CMR exams. Global and segmental (LV = 6, RV = 4) RV and LV T1 values were calculated (Figure). Results Mean time between CMR exams for 36 included patients (age 34 ± 2y) was 22 ± 2 months. All LV segments and 81/88% of RV segments of first and second CMR could be analyzed, respectively. T1 increased mildly but not significantly (table). There was no relationship of T1 to pulmonary regurgitation fraction, pulmonary stenosis or RV enddiastolic volume (p > 0.05). Global RV T1 of the second CMR was related to RV ejection fraction (RVEF): r = 0.353, 3.0 ± 1.4, p = 0.038. T1 of the infero-septal LV segment of first and second CMR, global LV T1 of second CMR and increase of T1 of global LV, anterior, antero-lateral and –septal LV segments, were related to age at CMR: r = 0.333 - 0.463, p < 0.05, respectively. Conclusions Native T1 values increased mildly in patients with stable RV CHD, which was not statistically significant probably due to the short to median follow-up. Global RV T1 appears to be related to RVEF which could be sign of increasing interstitial fibrosis whereas the relationship of LV T1 to age might be a physiological finding. First CMR native T1 (ms) Second CMR native T1 (ms) p LV Global 1007 ± 37 1014 ± 39 0.413 LV Anterior 994 ± 53 999 ± 54 0.710 LV Antero-lateral 965 ± 63 981 ± 58 0.186 LV Infero-lateral 1000 ± 52 1004 ± 63 0.695 LV Inferior 1035 42 1037 ± 50 0.744 LV Infero-septal 1028 ± 35 1036 ± 43 0.282 LV Antero-septal 1016 ± 38 1024 ± 48 0.347 RV Global 1091 ± 90 1096 ± 85 0.410 RV Inferior 1112 ± 104 1115 ± 118 0.696 RV Infero-lateral 1061 ± 130 1077 ± 115 0.425 RV Antero-lateral 1046 ± 127 1080 ± 109 0.088 RV Anterior 1088 ± 156 1108 ± 154 0.410 Abstract Figure. Determination of biventricular T1 values

Left ventricle longitudinal strain alterations in asymptomatic or mildly symptomatic pediatric patients with recent SARS-CoV-2 infection

Funding AcknowledgementsType of funding sources: None.BackgroundEvidence suggests that clinical manifestations of children’s COVID-19 may be less severe. However, it has been described the pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) which resembles other inflammatory conditions (i.e. Kawasaki disease). Patients affected by PIMS-TS showed cardiac involvement with myocardial injury, reduced left ventricle systolic function and coronary artery abnormalities. Little is known regarding cardiac involvement in pediatric patients with asymptomatic or mildly symptomatic SARS-CoV-2 infection.MethodsWe analyzed 23 pediatric patients (13males, 56%) with diagnosis of SARS-CoV-2 infection based on PCR analysis of nasopharingeal swab (NPS), and asymptomatic or only mildly symptomatic for COVID-19. Patients underwent standard transthoracic echocardiogram (TTE) within 2-3 month from diagnosis and after negative NPS for SARS-CoV-2. We performed offline analysis with GE EchoPAC software to measure global longitudinal strain (GLS) of the LV using 2D speckle tracking imaging. Therefore, we compared the results with a matched group of 23 controls (13males, 56%).ResultsCases and controls were similar regarding age (5.9 ± 4.1years vs. 6.4 ± 4.4 years, p = 0.63), body surface area (0.98 ± 0.3m2 vs. 0.8 ± 0.4m2, p = 0.17), LV FS (37.9 ± 5.9% vs. 36.4 ± 8.3%, p = 0.74) and LV biplane EF (63.9 ± 5.2% vs. 66.4 ± 5.3%, p = 0.11). GLS analysis showed significant strain reduction of the LV mid-wall segments and of the basal anterior, posterior and septal inferior segments among cases compared to controls. Furthermore, in the case group there were 7 subjects (30%) with a strain below 16.5% in at least 3 segments.ConclusionSARS-CoV-2 infection may affect LV deformation in asymptomatic or only mildly symptomatic children, showing a peculiar pattern with lower longitudinal strain in all mid-wall segments of LV compared to control subjects. The clinical significance of this findings is unclear and follow-up is needed to verify the reversibility of this alterations.

Catheter ablation via the left atrium for atrioventricular nodal reentrant tachycardia: A narrative review.

BackgroundSince 1996, it has been recognized that catheter ablation for atrioventricular nodal reentrant tachycardia (AVNRT) may require an approach through the left atrium.ObjectiveThe purposes are to present a case report and to provide a comprehensive narrative review on this topic.MethodsA literature review of all articles that provided detailed information on patients who underwent catheter ablation via the left atrium for AVNRT was performed. The primary search queried PubMed using Medical Subject Headings (MeSH) terms “atrioventricular nodal reentrant tachycardia” and “left.” The secondary search was performed by manual review of reference lists and Google Scholar citations of manuscripts retrieved by the primary search. The review was limited to the English language.ResultsThe searches yielded 30 articles that described 79 patients. A case report was added. Therefore, the final review consisted of 80 patients. The prevalence of left atrial ablation for patients with AVNRT undergoing catheter ablation at tertiary care centers was approximately 1%. Failed right atrial ablation, with or without coronary sinus ablation, was the most common indication for left atrial ablation. Pooled data from 3 cohort studies estimated the acute success rate for radiofrequency ablation of the slow pathway at the septal or inferoparaseptal segments of the mitral valve annulus after failed right-sided ablation to be 90%. There were no reports of atrioventricular block requiring permanent pacemaker implantation.ConclusionCatheter ablation of the slow pathway via the left atrium is an important technique for AVNRT cases that are refractory to conventional ablation.

Nonselective versus selective His bundle pacing: An acute intrapatient speckle‐tracking strain echocardiographic study

We aimed to compare the acute differences in left ventricular (LV) function and mechanical synchrony during nonselective His bundle pacing (ns-HBP) versus selective His bundle pacing (s-HBP) using strain echocardiography. Consecutive patients with permanent His bundle pacing, in whom it was possible to obtain both s-HBP and ns-HBP, were studied in two centers. In each patient, echocardiography was performed sequentially during s-HBP and ns-HBP. Speckle-tracking echocardiography parameters were analyzed: Global longitudinal strain (GLS), the time delay between peak systolic strain in the basal septaland basal lateral segments (BS-BL delay), peak strain dispersion (PSD) and strain delay index. Right ventricle function was assessed using tricuspid annular plane systolic excursion (TAPSE) and tissue Doppler velocity of the lateral tricuspid annulus (S'). A total of 69 patients (age: 75.6 ± 10.5 years; males: 75%) were enrolled. There were no differences in LV ejection fraction and GLS between s-HBP and ns-HBP modes: 59% versus 60%, and -15.6% versus -15.7%, respectively; as well as no difference in BS-BL delay and strain delay index. The PSD value was higher in the ns-HBP group than in the s-HBP group with the most pronounced difference in the basal LV segments. No differences in right ventricular function parameters (TAPSE and S') were found. The ns-HBP and s-HBP modes seem comparable regarding ventricular function. The dyssynchrony parameters were significantly higher during ns-HBP, however, the difference seems modest and clarification of its impact on LV function requires a larger long-term study.

Abstract 15645: The Prognostic Impact of Left and Right Atrial Segmental Strain Analysis in Cardiac Amyloidosis Patients

Introduction: Little is known about global and segmental atrial function in cardiac amyloidosis. Atrial function plays an important role to maintain adequate ventricular filling. Hypothesis: We hypothesized left atrial (LA) and right atrial (RA) segmental strain analysis is prognostic in patients with cardiac amyloidosis. Methods: We studied 121 patients with biopsy-proven cardiac amyloidosis and speckle-tracking strain echocardiography. The LA and RA were divided into 6 segments each (basal, mid, and apical segments of free wall and septum). We determined LA and RA free wall/septal wall peak strain ratios. The primary outcome was all-cause mortality (median follow-up; 5.0 years). Results: Regional LA strain analysis was feasible in 104 patients (86%) and RA in 92 patients (76%). Average LA global peak strain was 18.3±12.1% and RA global peak strain was 20.0±15.0%. We compared LA and RA strain free wall and septal wall segments. Atrial septal strain was significantly reduced compared to free wall strain in RA (10.8±9.9 % vs 30.7± 23.8%, p< 0.01). Free wall/septal wall strain ratio of LA was significantly reduced compared with the ratio of RA (p< 0.01). During the follow up, 60 patients died. All atrial regions showed reduction in peak strain in non-survivors compared with survivors. When dividing patients into 2 groups using LA free wall strain and RA free wall strain median values, low atrial free wall strain was associated with worse prognosis (Log-rank p < 0.001, HR 4.9, 95% CI= 2.6-9.3). Conclusions: LA and RA atrial strain have significant prognostic value in patients with cardiac amyloidosis. Free wall/septal wall strain ratio in LA was significantly reduced compared with RA. Assessment of atrial dysfunction has promise for clinical applications cardiac amyloidosis patients.

Abstract 15418: An Arrhythmogenic Isolated Septal Aneurysm

Background: Septal infarct due to isolated occlusion of a perforator branch is extremely rare. Few reported cases only describe either the EKG findings, imaging abnormalities or revascularization techniques. Objective: We report a case of an isolated septal aneurysm (ISA) caused by the acute occlusion of the second septal perforator presenting with recurrent ventricular fibrillation (VF). Results: A 63 year old woman presented to the hospital with chest pain. EKG showed an ST segment elevation localized to lead V3 (Fig1A), troponin 18.23. Angiogram showed an isolated 95% tubular stenosis of large second septal branch of LAD (Fig1B). No revascularization was performed. The patient subsequently had cardiac arrest (VF) requiring cardioversion. Repeat angiogram was unchanged. Echo showed isolated mid septal dyskinetic segment (Fig1C). LVEF was 60%. The patient was discharged with an external defibrillator. Repeat echo showed unchanged EF but presence of the isolated dyskinetic segment. An electrophysiologic study (EPS) showed VF induced with 2 extra stimuli at 250 ms with a drive cycle of 600 ms (Fig1D). An ICD was implanted for prevention of SCD. Conclusion: We describe the first case of an arrhythmogenic ISA in the presence of normal LVEF. The interventricular septum is composed of right and left ventricular endocardium. Experiments have shown that acute septal ischemia produces trans-septal asymmetry in expression of membrane ion channels and action potentials in local conduction velocity and gradients. This results in trans-mural heterogeneity of tissue excitability, a substrate for transmural re-entry and ventricular tachyarrhythmias, in septal infarction. This also explains the persistence of enhanced arrhythmogenicity in our patient during the initial and chronic phases of ischemia. ISA is rare but potentially arrhythmogenic. ISA with preserved LVEF, EPS for arrhythmogenicity and ICD for secondary prevention of SCD should be considered in such cases.

Abstract 16979: Hemodynamic Comparison of Tricuspid Ring Annuloplasty vs. Hetzer Annuloplasty Technique to Repair Functional Tricuspid Regurgitation

Introduction: Surgical repair of functional tricuspid regurgitation (FTR) is increasingly performed, and the techniques are evolving. Annuloplasty is currently the technique of choice, with different techniques yielding varied results, and thus require optimization. Objective: In this study, we sought to compare tricuspid valve function and kinematics after ring annuloplasty and Hetzer’s double orifice repair in an ex vivo model of FTR. Methods: Ten pig hearts were mounted into a right heart simulator, and studied at 70 bpm while maintaining the total volume of working fluid. FTR was created by increasing afterload, which caused acute right ventricular dilation and TV tethering. Tricuspid valve annuloplasty (TVA) was performed with a 26mm MC 3 ring. Hetzer procedure was performed with pledgeted sutures that approximated the anteroposterior and septal annular segments. Flow probes were used to measure FTR, and leaflet kinematics with echocardiography. Results: FTR of 17.7±9.2mL(p<0.0001) after RV dilation. Repair with TVA and Hetzer reduced FTR to 8.8±6.8ml(p=0.7142) and 7.8±6.9ml(p=0.0919), respectively, but did not eliminate it. Septal leaflet excursion angle decreased by 48.1% with FTR (p=0.04 vs. baseline ) . Repair with TVA and Hetzer increased the angle to 17.3±6.7°(p=0.0312) and 21.5±8.3°(vs FTR, p=0.0034), respectively. The Hetzer improved septal leaflet mobility better than TVA (p=0.0145). The posterior leaflet excursion angle decreased by 49.2% compared to baseline to 18.4±10.5° (p=0.0060) and both TVA and Hetzer significantly improved mobility to 33.6±8.4° (p=0.0081) and 31.6±15.6° (p=0.0256), respectively. Anterior leaflet mobility decreased after FTR by 60.7% to 18.1±8.2°. The effect of these repairs on the sub-valvular apparatus was negligible. Conclusion: TVA and Hetzer both reduced regurgitation but did not eliminate it. Septal and posterior leaflet mobility was improved, while the anterior leaflet remained tethered.

Early Sharp Wave Synchronization along the Septo-Temporal Axis of the Neonatal Rat Hippocampus

In the neonatal rat hippocampus, the first and predominant pattern of synchronized neuronal network activity is early sharp waves (eSPWs) occurring at a frequency of ~2–4 events per minute. However, how eSPWs are organized longitudinally along the septo-temporal hippocampal axis remains unknown. Using silicone probe recordings from the septal and intermediate segments of the CA1 hippocampus in neonatal rats in vivo we found that eSPWs are highly synchronized longitudinally. The amplitudes of eSPWs in the septal and intermediate segments of the hippocampus were also highly correlated. eSPWs also supported longitudinal synchronization of CA1 multiple unit activity. Spatial-temporal analysis revealed a septal-temporal gradient with more frequent initiation of eSPWs in the septal regions. The speed of eSPW longitudinal propagation attained ~ 250 mm/s. We suggest that longitudinal correlated activity supported by synchronized eSPWs emerges early during postnatal development and may participate in the formation of intrahippocampal connections in the developing hippocampus.

Diphosphonate single-photon emission computed tomography in cardiac transthyretin amyloidosis

Abstract Background Planar diphosphonate scintigraphy is an established diagnostic tool for amyloid transthyretin (ATTR) cardiomyopathy. Characterization of the amyloid burden up to the segmental level by single photon emission computed tomography (SPECT) has not been evaluated so far. Methods Data from consecutive patients undergoing cardiac 99mTc-hydroxymethylene diphosphonate (99mTc-HMDP) SPECT and diagnosed with ATTR cardiomyopathy at a tertiary referral center from June 2016 to April 2019 were collected. Results Thirty-eight patients were included (median age 81 years, 79% men, 92% with wild-type ATTR). In patients with Perugini score 1, the most intense diphosphonate regional uptake was found in septal segments, particularly in infero-septal segments. Among patients scoring 2, the amyloid burden in the septum became more significant, and extended to inferior and apical segments. Finally, patients scoring 3 displayed an intense and widespread tracer uptake. All patients with Perugini score 1 had LGE in at least one antero-septal, one infero-septal, and one infero-lateral segment. All patients with score 2 displayed LGE in infero-septal, inferior, and infero-lateral segments. LGE became extensive in patients scoring 3, with all patients having at least one LGE-positive segment in each region. Conclusions When assimilating different Perugini grades to evolutive stages of the disease, amyloid deposition seem to progress from the septum to the inferior wall and then to the other regions and from the basis to the apex. The potential of segmental analysis might be particularly relevant in patients with very limited cardiac uptake at planar scintigraphy (Perugini score 1). Funding Acknowledgement Type of funding source: None

Assessment of biventricular function using advanced echocardiography in patients with Ebstein's anomaly pre and post-tricuspid valve surgery

Abstract Background Ebstein's anomaly (EA) is a right ventricular myopathy with failure of tricuspid valve (TV) delamination. While conventional echocardiographic measurements of ventricular function such as tricuspid annular plane systolic excursion (TAPSE), tissue Doppler imaging RV systolic velocity (s'), fractional area change (FAC) and left ventricle ejection fraction (LV EF) are load dependent measures of systolic function and may not reflect true myocardial function, speckle tracking echocardiography (STE) evaluates more subtle myocardial deformation on a regional level. However, the role of STE for the biventricular assessments in an adult cohort of EA before and after tricuspid valve repair/replacement (TVR) is not fully elucidated. Purposes To assess biventricular function by conventional echocardiographic parameters and global and regional longitudinal strain (GLS, RLS) using speckle tracking echocardiography in adult patients with EA pre- and post-TVR. Methods 47 patients with EA (57% women, age at operation 37±16 years) who had TV repair/replacement (17/30) between 2005 and 2019 were retrospectively identified from Echo database. 2D conventional echocardiographic parameters (TAPSE, s', FAC and LV EF) and biventricular GLS and RLS were assessed pre-TVR, at 1-, 2- and 5-year post-TVR. RV and LV segments were visually graded for STE feasibility assessment (Figure 1). Results TAPSE and s' declined after TVR with no further changes over 5 years (both p<0.0001); FAC decreased after TVR (p=0.005) with some amelioration but remaining impaired at 5 years. RV GLS deteriorated at 1 year post-TVR with improvements at 2 and 5 years (p<0.0001, Table 1). LV EF remained preserved (p=0.2), however, LV GLS was low pre-TVR and decreased at 1 year with improvements at 2 and 5 years (p=0.004). Least feasible segments were RV mid (pre-TVR and 1y and 5y post-TVR) and apical free wall (both pre- and post-operative) and LV apical lateral (pre-TVR and 2y post-TVR) all with median score of 1. Conclusions Despite the TV regurgitation reduction, TV surgeries have led to RV dysfunction with only some amelioration of RV longitudinal strain and all conventional echocardiographic parameters after 5 years. The segmental analysis showed that the basal septal segment was the most negatively affected. LV strain was reduced before and after surgery despite preserved ejection fraction. Hence, speckle tracking echocardiography is a feasible and a sensitive method in detecting myocardial dysfunction in patients with Ebstein's anomaly. Feasibility assessment Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): Royal Brompton Hospital; Imperial College

Regional protein expression changes within the left ventricle in a mouse model of dyssynchronous and resynchronized heart failure.

AimsThe biological mechanisms conveying the salutary effects of cardiac resynchronization therapy in heart failure remain elusive. We have recently developed a mouse model of heart failure with dyssynchrony/resynchronization. The aim of this study was to characterize regional left ventricular heterogeneity in protein expression comparing early (septum) and late (lateral) activated left ventricular wall segments in synchronous (SHF), dyssynchronous (DHF), and resynchronized heart failure (RHF).Methods and resultsMice subjected to ischaemia/reperfusion were divided into three groups: sinus rhythm for 4 weeks (SHF), right ventricular pacing for 4 weeks (DHF), and right ventricular pacing for 2 weeks and 2 weeks of sinus rhythm (RHF). Relative concentrations of 92 proteins from septal and lateral left ventricular wall segments (n = 10 per group) were compared within each group. We also analysed the effect of DHF vs. SHF and RHF vs. DHF on protein expression pattern comparing the same left ventricular segments between the groups. Proteins with significantly differential expression between left ventricular segments were analysed for protein–protein correlations, protein–protein interactions, and biological and signalling pathways. Eight proteins were significantly down‐regulated in the late activated (compared with early activated) lateral wall uniquely in RHF (P < 0.05 adjusted for a 5% false discovery rate): Erbb4, Ntf3, Pdgfb, Tnf, Notch3, Qdpr, Tpp1, and Itgb6. Protein correlation matrix showed that six of these were strongly and positively correlated and five had known protein–protein interactions. Biological pathways mainly down‐regulated in late activated myocardium in RHF were MAPK signalling and hypertrophic cardiomyopathy. There were no significantly differentially expressed proteins comparing the same left ventricular segments between the DHF and SHF (range of P‐values: 0.05–1.00) and RHF and DHF (range of P‐values: 0.32–1.00).ConclusionsIn a mouse model of heart failure with dyssynchrony and resynchronization, we observed down‐regulation of several proteins in the late activated lateral wall, compared with the septum, in resynchronized mice. These proteins display significant protein–protein correlation and share biological signalling pathways, including MAPK activation and hypertrophy signalling.

Negative Impact of the Left Ventricular Remnant Morphology on Systemic Right Ventricular Myocardial Deformation in Hypoplastic Left Heart Syndrome.

Left ventricular (LV) morphology may affect right ventricular (RV) function before and after Fontan palliation in patients with hypoplastic left heart syndrome (HLHS). We sought to assess the potential impact of LV morphology on RV function in patients with HLHS using cardiac magnetic resonance (CMR) imaging. A retrospective analysis of available CMR scans from all patients with HLHS was performed. LV morphology was categorized as absent/slit-like or globular/miniaturized. Volumetric analysis was performed using manual disc-summation method on steady-state free precession (SSFP) stack obtained in short-axis orientation of the ventricles. 4-chamber and short-axis SSFP images were used to measure strain on a semi-automated feature-tracking (FT) module. Two sample t-test was used to compare the groups. A total of 48 CMR scans were analyzed. Of those, 12 patients had absent/slit-like and 36 had globular/miniaturized LV morphology. Averaged 4-chamber longitudinal RV strain was significantly higher for absent/slit-like (- 17.6 ± 4.7%) than globular/miniaturized (- 13.4 ± 3.5; P = 0.002). Averaged 4-chamber radial RV strain was also significantly higher for absent/slit-like (33.1 ± 14.9%) than globular/miniaturized (21.6 ± 7.1; P = 0.001). For globular/miniaturized LV morphology, the decreases of 4-chamber longitudinal and radial strains were mainly attributable to the septal basilar and septal mid-ventricular segments. No differences were found in short-axis RV global circumferential strain between the morphologic subtypes (absent/slit-like - 15.0 ± 6.5, globular/miniaturized - 15.7 ± 4.7; P = 0.68). Larger LV remnants, with globular/miniaturized LV morphology, demonstrated diminished strain in the septal base and mid-ventricle segments. Patients with globular/miniaturized LV morphology may benefit with closer monitoring and lower threshold to start heart failure medications. These results exemplify the utility of including both septal and regional deformation in systemic RV strain analysis.

2D Speckle Tracking echocardiography in the prognostication of left ventricle diastolic dysfunction

The aim of the study: to develop prediction comprehensive criteria for the diastolic dysfunction (DD) of the left ventricle (LV) according to 2D Speckle Tracking echocardiography (STE).Materials and methods. A clinical and instrumental study of 91 patients aged 64.0 was performed [58.0; 70.0] years in the Minsk Scientific and Practical Center of Surgery, Transplantology and Hematology in 2019. Criteria for inclusion: sinus rhythm, essential arterial hypertension, chronic coronary artery disease, previous left myocardial infarction, after which at least six months have passed to stabilize the LV structural and functional parameters, chronic heart failure, patient informed consent. Exclusion criteria: primary mitral regurgitation, mitral stenosis, mitral valve repair or prosthetics, congenital heart defects, acute and chronic diseases of the kidneys, lungs. Transthoracic echocardiography and STE was performed on ultrasound machine Vivid E9 (GE Healthcare, USA).Results. The leading functional anomalies, interconnected in the development of LV DD, are decline of the LV longitudinal diastolic, regional and global systolic strain, LV mechanical dispersion and dyssynergy. Correlations between LV DD type II and the mechanical dispersion index (r = 0.69, p &lt; 0.001), delta of LV time to peak longitudinal deformation (r = 0.66, p &lt; 0.001), LV global post-systolic index (r = 0.58, p &lt; 0.001), GLSAVG (r = 0.63, p &lt; 0.001) were established. LV DD is characterized by early diastolic longitudinal strain E of the LV basal lateral segment &gt; −6.75%, LV basal septal segment &gt; −5.22%, early and late diastolic longitudinal strain ratio E/A of the LV basal lateral segment ≤0.91, basal-septal segment ≤0.69. LV DD type I is characterized by an LV mechanical dispersion index &gt;49.34 ms, LV delta time to peak longitudinal strain &gt;157 ms. Prognostic values for LV DD type II are LV mechanical dispersion index &gt;49.34 ms, delta time to peak longitudinal strain is &gt;136 ms, global post-systolic index &gt;6.24%, mechanical dyssynergy index &gt;4.60%, global LV peak longitudinal displacement ≤9.88 mm, GLSAVG &gt; −18.5% (sensitivity 88.2%, specificity 83.3%).Conclusions. The use of the developed STE prediction value in practical public health will increase the efficiency of diagnosis of LV DD.

Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy: The Utility of Myocardial Strain Based on Cardiac MR Tissue Tracking

Myocardial strain for assessment of hypertrophic cardiomyopathy (HCM) is of importance and may play a role in identifying obstruction in HCM patients. To evaluate the utility of myocardial strain for detecting left ventricular (LV) outflow tract (LVOT) obstruction in HCM patients based on magnetic resonance tissue tracking. Retrospective. In all, 44 adult HCM patients with LVOT obstruction and 108 adult HCM patients without LVOT obstruction. 1.5 T; Steady-state free-precession cine sequence; phase-sensitive inversion-prepared segmented gradient echo sequence for late gadolinium enhancement (LGE) imaging. Strain parameters including the local and global levels of LV myocardium and the subtraction (Sub) of myocardial strain variables between interventricular septal segments (IVSS) and noninterventricular septal segments (NIVSS) were measured for differentiating HCM with obstruction from nonobstruction. Average and maximum LV wall thickness (Average and Maximum LVWT) were also analyzed. Univariate and multivariate logistic regression analysis, area under the receiver operating characteristic (ROC) curve (AUC), intraclass correlation coefficient. In multivariate analysis, Average LVWT, Maximum LVWT, and the subtraction of radial peak strain (Sub Radial PS) between NIVSS and IVSS were independently associated with LVOT obstruction. The AUCs were 0.731, 0.840, and 0.890 for Average LVWT, Maximum LVWT, and Sub Radial PS, respectively. Sub Radial PS (cutoff value: 8.1%) demonstrated the highest sensitivity of 75.0% and a high specificity of 87.9% for identifying LVOT; Maximum LVWT (cutoff value: 22.9 mm) showed good sensitivity (72.7%) and specificity (83.3%). Combining Maximum LVWT >22.9 mm and Sub Radial PS > 8.1% achieved a better diagnostic performance (specificity 95.4%, sensitivity 70.5%). Combining Maximum LVWT >22.9 mm and Sub Radial PS >8.1% holds promise for objectively evaluating LVOT obstruction in HCM patients with very high specificity and acceptable sensitivity. 3 TECHNICAL EFFICACY STAGE: 2.

Predictors of Mortality in Patients With Biopsy‐Proven Viral Myocarditis: 10‐Year Outcome Data

BackgroundThere is scarce data about the long‐term mortality as well as the prognostic value of cardiovascular magnetic resonance and late gadolinium enhancement (LGE) in patients with biopsy‐proven viral myocarditis. We sought to investigate: (1) mortality and (2) prognostic value of LGEcardiovascular magnetic resonance (location, pattern, extent, and distribution) in a >10‐year follow‐up in patients with biopsy‐proven myocarditis.Methods and ResultsTwo‐hundred three consecutive patients with biopsy‐proven viral myocarditis and cardiovascular magnetic resonance were enrolled; 183 patients were eligible for standardized follow‐up. The median follow‐up was 10.1 years. End points were all‐cause death, cardiac death, and sudden cardiac death (SCD). We found substantial long‐term mortality in patients with biopsy‐proven myocarditis (39.3% all cause, 27.3% cardiac, and 10.9% SCD); 101 patients (55.2%) demonstrated LGE. The presence of LGE was associated with a more than a doubled risk of death (hazard ratio [HR], 2.40; 95% CI], 1.30–4.43), escalating to a HR of 3.00 (95% CI, 1.41–6.42) for cardiac death, and a HR of 14.79 (95% CI, 1.95–112.00) for SCD; all P≤0.009. Specifically, midwall, (antero‐) septal LGE, and extent of LGE were highly associated with death, all P<0.001. Septal LGE was the best independent predictor for SCD (HR, 4.59; 95% CI, 1.38–15.24; P=0.01).ConclusionsIn patients with biopsy‐proven viral myocarditis, the presence of midwall LGE in the (antero‐) septal segments is associated with a higher rate of mortality (including SCD) compared with absent LGE or other LGE patterns, underlining the prognostic benefit of a distinct LGE analysis in these patients.

A potential post-removal pH neutralization strategy to mitigate nasal button battery injuries

ObjectiveButton batteries (BBs) impacted in the nose of children can cause septal perforation, synechia, atrophy, necrosis and deformities such as saddle nose. Developing mitigation strategies that can reduce tissue damage after BB removal can decrease these complications. Methods3 V lithium BBs were placed on the cadaveric sheep nasal septum model segments. After 3, 6, 12 and 24 h, BB on each segment was removed and intermittent irrigation was performed with 0.25% acetic acid solution. Irrigation with saline was performed as the control. Visual tissue damage that occurred just before and after irrigation was photographed. BB voltage, temperature and pH changes in the tissue were recorded. Each segment was examined after irrigation for the depth of necrosis and presence of cartilage necrosis. ResultsThe voltage of 3 V lithium BB was observed to drop to about half at the end of the 3rd hour. It was observed that full-thickness mucoperichondrial necrosis occurred in the nasal septum segments at all time points. Although 0.25% acetic acid irrigation significantly decreased tissue pH compared to saline without increasing temperature, it did not show a significant superiority compared to saline in reducing neither visually nor histologically damage. While cartilage necrosis was not observed for the first 12 h, it was measured 105 μm in the segment irrigated with 0.25% acetic acid at the end of 24 h, and 518 μm in the segment irrigated with saline. ConclusionsThe pH neutralization strategy with post-removal 0.25% acetic acid irrigation to mitigate nasal BB injury appears to be ineffective in reducing the full-thickness mucoperichondrial necrosis starting within 3 h. Although this strategy seems to decrease the progression of cartilage necrosis starting after 12 h, the development of pre-removal strategies for the first 3 h may be more effective and superior in reducing mucoperichondrial damage.

Diphosphonate single-photon emission computed tomography in cardiac transthyretin amyloidosis

BackgroundPlanar diphosphonate scintigraphy is an established diagnostic tool for amyloid transthyretin (ATTR) cardiomyopathy. Characterization of the amyloid burden up to the segmental level by single photon emission computed tomography (SPECT) has not been evaluated so far. MethodsData from consecutive patients undergoing cardiac 99mTc-hydroxymethylene diphosphonate (99mTc-HMDP) SPECT and diagnosed with ATTR cardiomyopathy at a tertiary referral center from June 2016 to April 2019 were collected. ResultsThirty-eight patients were included (median age 81 years, 79% men, 92% with wild-type ATTR). In patients with Perugini score 1, the most intense diphosphonate regional uptake was found in septal segments, particularly in infero-septal segments. Among patients scoring 2, the amyloid burden in the septum became more significant, and extended to inferior and apical segments. Finally, patients scoring 3 displayed an intense and widespread tracer uptake. All patients with Perugini score 1 had LGE in at least one antero-septal, one infero-septal, and one infero-lateral segment. All patients with score 2 displayed LGE in infero-septal, inferior, and infero-lateral segments. LGE became extensive in patients scoring 3, with all patients having at least one LGE-positive segment in each region. ConclusionsWhen assimilating different Perugini grades to evolutive stages of the disease, amyloid deposition seem to progress from the septum to the inferior wall and then to the other regions and from the basis to the apex. The potential of segmental analysis might be particularly relevant in patients with very limited cardiac uptake at planar scintigraphy (Perugini score 1).

Correlation between septal midwall late gadolinium enhancement on CMR and conduction delay on ECG in patients with nonischemic dilated cardiomyopathy

BackgroundSeptal midwall late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMR) is a characteristic finding in nonischemic dilated cardiomyopathy (DCM) and is associated with adverse cardiac events. QRS-prolongation in DCM is also frequently present and a predictor of arrhythmic events and mortality. Since the His-Purkinje fibres are located in the interventricular septum, QRS-prolongation may directly result from septal fibrosis, visualized by LGE. Our aim was to study the correlation of the presence and extent of septal midwall LGE and QRS-duration. MethodsDCM-patients with left ventricular (LV) dysfunction (LVEF < 50%) were included. LV volumes, systolic function and nonischemic septal midwall LGE, defined as patchy or stripe-like LGE in the septal segments, were quantified. QRS-duration on standard 12-lead ECG was measured. Results165 DCM-patients were included (62% male, mean age 59 ± 15 years) with a median LVEF of 36% [24–44]. Fifty-one patients (31%) demonstrated septal midwall LGE with a median extent of 8.1 gram [4.3–16.8]. Patients with midwall LGE had increased LV end-diastolic volumes (EDV) 248 mL [193–301] vs. 193 mL [160–239], p < 0.001) and lower LVEF (26% [18–35] vs. 40% [32–45], p < 0.001). Median QRS-duration was 110 ms [95–146] without a correlation to the presence nor extent of midwall LGE. QRS-duration was moderately correlated with LV-dilation and mass (respectively r = 0.35, p < 0.001 and r = 0.30, p < 0.001). ConclusionIn DCM-patients, QRS-prolongation and septal midwall LGE are frequently present and often co-exist. However, they are not correlated. This suggests that the assessment of LGE-CMR has complementary value to ECG evaluation in the clinical assessment and risk stratification of DCM-patients.

1027 Mechanical dispersion of the left and right ventricle and the correlation with ventricular arrhythmias in hypertrophic cardiomyopathy

Abstract Funding Acknowledgements CREDO Project - ID: 49182, financed through the SOP IEC -A2-0.2.2.1-2013-1 cofinanced by the ERDF Introduction One important cause of sudden cardiac death in hypertrophic cardiomyopathy (HCM) are ventricular arrhythmias. In patients with HCM, non-sustained ventricular arrhythmias were analysed in relation with 2D speckle tracking mechanical dispersion of left ventricle (LVMD), but not in relation with mechanical dispersion of the right ventricle. Purpose To investigate the possible associations between mechanical dispersion and other echocardiographic parameters and the development of non-sustained ventricular tachycardias (NSVT) in HCM patients. Methods Clinical, 24 hours ECG-Holter, 2D and 3D echocardiography data were registered in HCM patients and in a healthy control group (with normal echocardiography). The 24 hours ECG-Holter was used for detecting NSVT. LVMD was calculated as the standard deviation of time to peak negative strain in the sixteenth segments of the left ventricle. The right ventricle mechanical dispersion (RVMD) was calculated on a three free wall segments model (FWMD), but also in six segments (three RV free wall segments plus three septal segments). Right and left ventricle function was evaluated by conventional echography and 2D speckle tracking imaging. Results Fifty-two patients with HCM and thirty-six age and sex matched subjects were included in the study. In HCM group, 6 patients (11,5%) associated biventricular hypertrophy, while 15 (28.8%) had NSVT on ECG monitoring (group HCM1). HCM1 patients had a much higher LVMD (77.38 ± 11.19 ms) compared with HCM patients without NSVT (group HCM2) (55.8 ± 23.85 ms, p = 0.001, CI:-33.9,-9.3) or compared with controls (43.07 ± 14.19 ms, p &amp;lt;0.001, CI: -44.68, -25.99). The 6 segments RVMD (60.23 ± 10.2 ms) was significantly higher in the CMH1 group compared with CMH2 (45.22 ± 9.8 ms, p = 0.01, CI: -32.1, -28.1) or with the control group (22 ±14 ms, p &amp;lt; 0.001,CI: -36.28, -30.12) independently of the existence of RV hypertrophy. Also, FWMD (55.2 ± 4.8 ms) was significantly higher in CMH1 group in comparation with CMH2 (42.3 ± 5.6 ms, p = 0.02, CI: -27.1, -8.2) or controls (32.1 ± 2.2 ms, p = 0.006, CI: -28.1, -12.1). The presence of NSVT correlated with global longitudinal strain (GS) 2C (-0.442, p = 0.009), GS LAX (r=-0.373, p = 0.03), GS mean value (r=-0.345, p = 0.046), LVMD (r = 0.462, p = 0.006), FWMD (r = 0.51, p = 0.004), 6 segments RVMD (r = 0.46, p = 0.05), 2D and 3D left atrial volume (r = 0.446, p = 0.008 and respectively, r = 0.512, p = 0.002). In a logistic regression, the only parameters associated with NSVT were LVMD (OR = 1.046, p = 0.05), FWMD (OR = 1.03, p = 0.05) and 6 segments MD (OR = 1.1, p = 0.04). Conclusions Increased mechanical dispersion of the left, but also right ventricle is associated with the risk of non-sustained ventricular tachycardias in HCM patients.