Left Ventricular Cavity Research Articles

Coronary artery fistula following surgical myectomy for hypertrophic obstructive cardiomyopathy: a case report

Abstract Background Coronary artery fistula is a rare, but recognized complication of surgical myectomy. Although most communicate with the right heart, a large fistula into the left ventricular cavity may result in a shunt haemodynamically analogous to aortic regurgitation. Understanding the variable presentation of iatrogenic coronary fistulae and the optimal evaluation strategy is critical to obtaining a timely diagnosis and instituting treatment. Case summary We report the case of a 57-year-old renal transplant recipient admitted for evaluation of presyncope, one-year post-surgical myectomy for hypertrophic obstructive cardiomyopathy. An iatrogenic coronary artery fistula was suspected by transthoracic echocardiography, and later confirmed with both non-invasive and invasive coronary angiography. Discussion We highlight various cardiac imaging modalities that confirmed the diagnosis of coronary artery fistula and helped to determine the clinical significance. We report the tailored approach often required to determine the anatomic and haemodynamic characteristics of coronary fistulae and outline potential management strategies.

Parameter subset reduction for imaging-based digital twin generation of patients with left ventricular mechanical discoordination

BackgroundIntegration of a patient’s non-invasive imaging data in a digital twin (DT) of the heart can provide valuable insight into the myocardial disease substrates underlying left ventricular (LV) mechanical discoordination. However, when generating a DT, model parameters should be identifiable to obtain robust parameter estimations. In this study, we used the CircAdapt model of the human heart and circulation to find a subset of parameters which were identifiable from LV cavity volume and regional strain measurements of patients with different substrates of left bundle branch block (LBBB) and myocardial infarction (MI). To this end, we included seven patients with heart failure with reduced ejection fraction (HFrEF) and LBBB (study ID: 2018-0863, registration date: 2019–10–07), of which four were non-ischemic (LBBB-only) and three had previous MI (LBBB-MI), and six narrow QRS patients with MI (MI-only) (study ID: NL45241.041.13, registration date: 2013–11–12). Morris screening method (MSM) was applied first to find parameters which were important for LV volume, regional strain, and strain rate indices. Second, this parameter subset was iteratively reduced based on parameter identifiability and reproducibility. Parameter identifiability was based on the diaphony calculated from quasi-Monte Carlo simulations and reproducibility was based on the intraclass correlation coefficient (ICC\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${ICC}$$\\end{document}) obtained from repeated parameter estimation using dynamic multi-swarm particle swarm optimization. Goodness-of-fit was defined as the mean squared error (χ2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{{\\chi}}}^{{2}}$$\\end{document}) of LV myocardial strain, strain rate, and cavity volume.ResultsA subset of 270 parameters remained after MSM which produced high-quality DTs of all patients (χ2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{{\\chi}}}^{{2}}$$\\end{document} < 1.6), but minimum parameter reproducibility was poor (ICCmin\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{ICC}}_{{min}}$$\\end{document} = 0.01). Iterative reduction yielded a reproducible (ICCmin\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{ICC}}_{{min}}$$\\end{document} = 0.83) subset of 75 parameters, including cardiac output, global LV activation duration, regional mechanical activation delay, and regional LV myocardial constitutive properties. This reduced subset produced patient-resembling DTs (χ2\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{{\\chi}}}^{{2}}$$\\end{document} < 2.2), while septal-to-lateral wall workload imbalance was higher for the LBBB-only DTs than for the MI-only DTs (p < 0.05).ConclusionsBy applying sensitivity and identifiability analysis, we successfully determined a parameter subset of the CircAdapt model which can be used to generate imaging-based DTs of patients with LV mechanical discoordination. Parameters were reproducibly estimated using particle swarm optimization, and derived LV myocardial work distribution was representative for the patient’s underlying disease substrate. This DT technology enables patient-specific substrate characterization and can potentially be used to support clinical decision making.

The interaction of choline and one-carbon / folate metabolism derangements on the cardiac remodeling process with or without diabetes

Proper nutrition helps protect from illness and disease. Choline (Ch), an essential molecule of substantial importance for the optimal development and function of several biological systems, plays a crucial role in the pathway of one-carbon metabolism. On the other hand, Ch-deprivation (CD) has been linked with abnormal fat metabolism, insulin resistance, and myocardial dysfunction. The Ch-deficiency setting is an established experimental model of non-alco¬holic steatohepatitis that resembles the human non-alcoholic fatty liver disease (NAFLD); a disease with constantly increasing incidence and prevalence. NAFLD, commonly associated with metabolic comorbidities such as obesity and type 2 diabetes mellitus, consists a high risk for cardiovascular disease. Experimental data of dietary CD through the administration of a Ch-deficient diet to rodents have revealed myocardial monocyte infiltration along with cardiac interstitial oedema and fibrosis, as well as a deleterious effect on cardiac valves that could lead to impaired heart mechanical properties which resemble to a restrictive pattern of cardiomyopathy characterised mainly by diastolic dysfunction. In a Ch-deprived diabetic experimental model, the diastolic heart failure has been characterized by a concentric hypertrophied myocardium, a left ventricular cavity with a thinner wall, and an increased left ventricular diastolic diameter, in addition to a left atrial dilatation that could also exert functional derangement and provoke arrhythmogenesis, thereby jeopardising cardiac output.

Echocardiographic Evaluation of Left Ventricular Hypertrophy

Abstract Left ventricular hypertrophy (LVH) can occur as a result of increase in the left ventricular (LV) wall thickness or increase in the LV cavity size, thus leading to increase in the LV mass. Strength training and aerobic exercise lead to physiological LVH, whereas conditions such as hypertension and aortic stenosis (AS) cause pathological LVH. It is one aspect of ventricular remodeling. LVH can also occur because of some primary myocardial diseases as well as due to certain infiltrative disorders. LVH is not a disease in itself, but a manifestation of some other disease. LVH is a marker of adverse cardiovascular health and remodeling and is associated with a high risk of adverse cardiac outcomes. Besides this, LVH itself can lead to heart failure or sudden cardiac death. Hence, a thorough assessment of LVH is important for proper management of the underlying condition. Echocardiography and cardiac magnetic resonance imaging are the two most important imaging modalities used for the assessment of LVH. This review describes various echocardiography techniques for LVH assessment as well as echocardiographic recognition of the underlying etiological condition.

Ketamine induced acute systolic heart failure

Background: Studies have shown major cardiovascular effects associated with ketamine use disorder including dose-dependent negative inotropic effects. Preoperative ketamine use has been linked to ketamine-induced stress cardiomyopathy. Case presentation: A 28-year-old female with a history of recurrent cystitis and ketamine use disorder (twice weekly for 14 years) presented with bilateral lower extremity oedema and shortness of breath for 3 months. She was tachycardic with a troponin level of 0.07 ng/ml and a B-type natriuretic peptide (BNP) level of 2511 pg/ml. Electrocardiogram showed normal sinus rhythm and transthoracic echocardiography (TTE) showed left ventricular ejection fraction (EF) of 15%, dilated left ventricle, and severe tricuspid and mitral regurgitation. Computed tomography (CT) scan of the chest and abdomen showed bilateral pleural effusions with congestive hepatopathy and ascites. The patient was started on intravenous furosemide, metoprolol, and sacubitril/valsartan. Rheumatological workup including complement levels, and antinuclear anti-double-stranded DNA was negative. A repeat TTE 2 weeks later revealed an EF of 25% and moderate tricuspid regurgitation. Four months later, the EF was 54% with normal left ventricular cavity size. Conclusion: Although ketamine use disorder is increasing, data on long-term side effects is minimal. Screening for ketamine use disorders should be considered in patients presenting with acute systolic heart failure. Long-term studies are needed to evaluate the benefits of adding ketamine screening to standard urine toxicology.

Heart failure with preserved left ventricular ejection fraction (HFpEF)

Heart failure with preserved left ventricular ejection fraction (HFpEF) is a common and very important disease entity because of its association with frequent repeat hospitalization and high mortality. Hallmarks of the underlying pathophysiology include a small left ventricular cavity due to concentric remodeling, impaired left ventricular compliance and left atrial dysfunction. This leads to an increase in left atrial and pulmonary pressure on exertion and in advanced stages of the disease already at rest with consecutive exertional dyspnea and exercise intolerance. Additional cardiovascular mechanisms including atrial fibrillation, chronotropic incompetence and coronary artery disease as well as non-cardiac co-morbidities contribute to a variable extent to the clinical picture. The diagnostic work-up is demanding and complex but the concepts have significantly improved during the last years. The study results of the Sodium Glucose cotransporter-2 inhibitors (SGLT-2-inhibitors) have revolutionized the treatment of HFpEF. In the present article, we provide an overview about the current understanding of the pathophysiology of HFpEF, the principles of the diagnostic pathways and a summary of the intervention studies in the field, and we propose an approach for the treatment in clinical practice.

Validation of image-derived input function using a long axial field of view PET/CT scanner for two different tracers

BackgroundAccurate image-derived input function (IDIF) from highly sensitive large axial field of view (LAFOV) PET/CT scanners could avoid the need of invasive blood sampling for kinetic modelling. The aim is to validate the use of IDIF for two kinds of tracers, 3 different IDIF locations and 9 different reconstruction settings.MethodsEight [18F]FDG and 10 [18F]DPA-714 scans were acquired respectively during 70 and 60 min on the Vision Quadra PET/CT system. PET images were reconstructed using various reconstruction settings. IDIFs were taken from ascending aorta (AA), descending aorta (DA), and left ventricular cavity (LV). The calibration factor (CF) extracted from the comparison between the IDIFs and the manual blood samples as reference was used for IDIFs accuracy and precision assessment. To illustrate the effect of various calibrated-IDIFs on Patlak linearization for [18F]FDG and Logan linearization for [18F]DPA-714, the same target time-activity curves were applied for each calibrated-IDIF.ResultsFor [18F]FDG, the accuracy and precision of the IDIFs were high (mean CF ≥ 0.82, SD ≤ 0.06). Compared to the striatum influx (Ki) extracted using calibrated AA IDIF with the updated European Association of Nuclear Medicine Research Ltd. standard reconstruction (EARL2), Ki mean differences were < 2% using the other calibrated IDIFs. For [18F]DPA714, high accuracy of the IDIFs was observed (mean CF ≥ 0.86) except using absolute scatter correction, DA and LV (respectively mean CF = 0.68, 0.47 and 0.44). However, the precision of the AA IDIFs was low (SD ≥ 0.10). Compared to the distribution volume (VT) in a frontal region obtained using calibrated continuous arterial sampler input function as reference, VT mean differences were small using calibrated AA IDIFs (for example VT mean difference = -5.3% using EARL2), but higher using calibrated DA and LV IDIFs (respectively + 12.5% and + 19.1%).ConclusionsFor [18F]FDG, IDIF do not need calibration against manual blood samples. For [18F]DPA-714, AA IDIF can replace continuous arterial sampling for simplified kinetic quantification but only with calibration against arterial blood samples. The accuracy and precision of IDIF from LAFOV PET/CT system depend on tracer, reconstruction settings and IDIF VOI locations, warranting careful optimization.

Increased left ventricular remodelling index in paradoxical low-flow severe aortic stenosis with preserved left ventricular ejection fraction compared to normal-flow severe aortic stenosis.

Patients with paradoxical low-flow (LF) severe aortic stenosis (AS) despite preserved left ventricular ejection fraction (LVEF) appear distinct from normal-flow (NF) patients, showing worse prognosis, more concentric hypertrophy and smaller left ventricular (LV) cavities. The left ventricular remodelling index (LVRI) has been demonstrated to reliably discriminate between physiologically adapted athlete's heart and pathological LV remodelling. We studied patients with index echocardiographic diagnosis of severe AS (aortic valve area <1 cm2) with preserved LVEF (>50%). The LVRI was determined by the ratio of the LV mass to the end-diastolic volume, as previously reported, and was compared between patients with LF and NF AS. Patients were prospectively followed up for at least 3 years, and clinical outcomes were examined in association with LVRI. Of the 450 patients studied, 112 (24.9%) had LF AS. While there were no significant differences in baseline clinical profile between LF and NF patients, LVRI was significantly higher in the LF group. Patients with high LVRI (>1.56 g/mL) had increased all-cause mortality (log-rank 9.18, P = 0.002) and were more likely to be admitted for cardiac failure (log-rank 7.61, P = 0.006) or undergo aortic valve replacement (log-rank 18.4, P < 0.001). After adjusting for the effect of age, hypertension, aortic valve area and mean pressure gradient on multivariate Cox regression, high LVRI remained independently associated with poor clinical outcomes (hazard ratio 1.64, 95% confidence interval 1.19-2.25, P = 0.002). Pathological LV remodelling (increased LVRI) was more common in patients with LF AS, and increased LVRI independently predicts worse clinical outcomes.

Difficulties in selecting antiarrhythmic therapy in a patient with left ventricular noncompaction and atrial septal defect: a case report

Introduction. Left ventricular noncompaction (LVNC) is a rare heterogeneous pathology characterized by a two-layered structure with a predominance of non-compact layer in the form of multiple trabeculations and pockets between them, communicating with the left ventricular cavity. One of the rare LVNC phenotypes is a combination with congenital heart defects, including atrial septal defect (ASD).Brief description. The article presents a case report describing the difficulties of selecting antiarrhythmic therapy in a patient with LVNC and ASD, complicated by arrhythmias due to heart failure. The diagnosis of LVNC was confirmed by the Petersen criterion using magnetic resonance imaging.Discussion. Cardiac arrhythmias in patients with LVNC and congenital heart defects, as a result of both anatomical and hemodynamic causes of electrical heart instability, constitute a danger of thromboembolism and sudden cardiac death, and also contribute to heart failure progression. The case is of interest due to the rare combination of LVNC and ASD, complicated by frequent episodes atrial fibrillation and premature ventricular contractions in the form of parasystoles, as well as difficulties in selecting antiarrhythmic therapy. Pulmonary vein cryoballoon ablation eliminated the source of atrial fibrillation. Ventricular ectopic activity was stopped using the anticonvulsant drug carbamazepine.

Novel predictors of prognosis in heart failure with reduced ejection fraction and the presence of spontaneous echo contrast: shock index, modified shock index and age-adjusted shock index.

Shock indexes (SI) have been associated with in-hospital mortality, particularly in heart failure patients. In our study, we aimed to investigate the relationship and prognostic value of the shock index (SI), modified shock index (MSI) and age-adjusted shock index (ASI) with spontaneous echo contrast (SEC) formation in patients with heart failure with reduced ejection fraction (HFrEF). We designed our research as a two-center, retrospective study. A total of 537 patients with left ventricular ejection fraction (LVEF) ≤ 40 and appearance of SEC within the left ventricular cavity, meeting the study criteria, were included. The primary endpoint included each component of ischemic cerebrovascular occlusion (CVO) and mortality. The secondary endpoint was considered cumulative events, which included the combination of CVO and mortality. There were 146 patients in the group with SEC and 391 patients in the group without SEC. SI (0.65 ±0.15 vs. 0.61 ±0.14, respectively, p = 0.014), MSI (0.92 ±0.22 vs. 0.87 ±0.20, respectively, p = 0.007) and ASI (42.76 ±11.71 vs. 39.83 ±12.25, respectively, p = 0.013) were significantly higher in the group with SEC. Ischemic CVO (10.3% vs. 3.3%, p = 0.001) and mortality (34.9% vs. 24.6%, p = 0.016) were significantly higher in the SEC group. In addition, the cumulative rate of mortality and ischemic CVO (39.7% vs. 26.1%, p = 0.002) was significantly higher in the SEC group. We found that the parameters SEC (OR = 2.822, 95% CI: 1.328-5.998, p = 0.007) and ASI (OR = 1.034, 95% CI: 1.002-1.066, p = 0.038) were independent predictors of ischemic CVO. SI, MSI and ASI may be quickly accessible and calculable indices to predict SEC in HFrEF patients.

Left ventricular remodeling in twin pregnancy, noninvasively assessed using hemodynamic forces and pressure-volume relation analysis: prospective, cohort study.

This study was designed to prospectively investigate the pattern of intraventricular hemodynamic forces (HDFs) associated with left ventricular (LV) function and remodeling in women with uncomplicated twin pregnancy. Transthoracic echocardiography was performed on 35 women (aged 35.9 ± 4.7-yr old) during gestation (T1, <14 wk; T2, 14-27 wk; T3, >28 wk) and 6-7 mo after delivery (T0). LV HDFs were computed from echocardiography long-axis data sets using a novel technique based on endocardial boundary tracking, both in apex-base (A-B) and latero-septal (L-S) directions. HDF distribution was evaluated by L-S over A-B HDF ratio (L-S:A-B HDF ratio). At T1, L-S:A-B HDF ratio was higher than in T0 (P < 0.05) indicating HDF misalignment. At T2, a slight impairment of cardiac function was then recorded with a reduction of global longitudinal strain (GLS) and left ventricular end-systolic elastance (Ees) at pressure-volume relationship analysis versus T1 (both P < 0.05). Finally, at T3, when HDF misalignment and LV contractility reduction (GLS and Ees) were all restored, a rightward shift of the end-diastolic pressure-volume relationship (EDPVR) with an increase of ventricular capacitance was documented. In twin pregnancy, HDF misalignment in the first trimester precedes the slight temporary decrease in left ventricular systolic function in the second trimester; at the third trimester, a rightward shift of the EDPVR was associated with a realignment of HDF and normalization of ventricular contractility indexes. These coordinated changes that occur in the maternal heart during twin pregnancy suggest the role of HDFs in cardiac remodeling.NEW & NOTEWORTHY These changes indicate that 1) the misalignment of hemodynamic forces (HDFs) precedes a mild reduction in systolic function in twin pregnancy and 2) the positive left ventricular (LV) response to hemodynamic stress is mainly due to an improved diastolic function with enhanced LV cavity compliance.

What can a cryptogenic stroke hide in a young patient?

Abstract Introduction Left ventricular hypertrabeculation is a recently described ventricular phenotype characterized by the alternation of excessive trabeculations with deep intertrabecular recesses that communicate with the left ventricular cavity but not with the coronary circulation. Case presentation We report the case of a young patient, recently diagnosed with ischemic stroke, in whom the cardiological assessment revealed the coexistence of left ventricular hypertrabeculation and dilated cardiomyopathy, which pathologies associated with a high risk of embolic events. The treatment administered followed the therapy for chronic heart failure, control of rhythm disorders that might occur, and the prevention of embolic accidents. Conclusions The particularity of the case is represented by atypical onset through a complication of the disease in a cardiovascular paucisymptomatic patient. Multimodal imaging corroborated with clinical and anamnestic elements had an essential role in the diagnosis.

Cardiovascular Effects of Chronic Hormone Therapy: Study on Olympic Female Athletes

Female physiology is regulated after puberty by the menstrual cycle, whose hormonal fluctuations create a multitude of effects on several systems, including the cardiovascular one. The use of hormone therapy (HT) is quite common in female athletes and data on cardiovascular effects in this population are lacking. We sought to investigate the effects of HT in highly trained athletes to assess any difference associated with HT on cardiac remodelling, exercise capacity and clinical correlates. We studied 380 female elite athletes (mean age 25.5 ± 4.8) competing in endurance and mixed sports. 67 athletes (18%) were in chronic HT therapy. All athletes underwent baseline ECG, exercise ECG stress test, transthoracic echocardiogram, complete blood tests including lipid profile and inflammation indexes. The echocardiographic study showed a characteristic left ventricular (LV) remodelling, defined by lower LV mass index (86.2 vs. 92.5 g/m2, p<0.006), end-diastolic LV diameter (28.3 vs. 29.4 mm/m2, p<0.004) and end-diastolic LV volume (61.82 vs. 67.09 mL/m2, p<0.010) compared to controls, without changes in systolic function and diastolic relaxation/filling indexes. A lower burden of ventricular arrhythmias on exercise was observed in HT athletes (1.5% vs 8.6% in those without therapy, p=0.040). Linear regression analysis showed that HT had independent effect on LVEDDi (p=0.014), LVEDVi (p=0.030) and LVMi (p=0.020). In conclusion, chronic treatment with HT in female athletes is associated with less cardiac remodelling, including a lower LV cavity, volume and mass, with preserved systolic and diastolic function, and decreased burden of exercise-induced ventricular arrhythmias. HT, therefore, appears to be responsible for a more economic, but equally efficient, cardiac adaptation to intensive athletic conditioning.

Pulmonary Transit Time Derived from First-Pass Perfusion Cardiac MR Imaging: A Potential New Marker for Cardiac Involvement and Prognosis in Light-Chain Amyloidosis.

First-pass perfusion cardiac MR imaging could reflect pulmonary hemodynamics. However, the clinical value of pulmonary transit time (PTT) derived from first-pass perfusion MRI in light-chain (AL) amyloidosis requires further evaluation. To assess the clinical and prognostic value of PTT in patients with AL amyloidosis. Prospective observational study. 226 biopsy-proven systemic AL amyloidosis patients (age 58.62 ± 10.10 years, 135 males) and 43 healthy controls (age 42 ± 16.2 years, 20 males). SSFP cine and phase sensitive inversion recovery late gadolinium enhancement (LGE) sequences, and multislice first-pass myocardial perfusion imaging with a saturation recovery turbo fast low-angle shot (SR-TurboFLASH) pulse sequence at 3.0T. PTT was measured as the time interval between the peaks of right and left ventricular cavity arterial input function curves on first-pass perfusion MR images. Independent-sample t test, Mann-Whitney U test, Chi-square test, Fisher's exact test, analysis of variance, or Kruskal-Wallis test, as appropriate; univariable and multivariable Cox proportional hazards models and Kaplan-Meier curves, area under receiver operating characteristic curve were used to determine statistical significance. PTT could differentiate AL amyloidosis patients with (N = 188) and without (N = 38) cardiac involvement (area under the curve [AUC] = 0.839). During a median follow-up of 35 months, 160 patients (70.8%) demonstrated all-cause mortality. After adjustments for clinical (Hazard ratio [HR] 1.061, confidence interval [CI]: 1.021-1.102), biochemical (HR 1.055, CI: 1.014-1.097), cardiac MRI-derived (HR 1.077, CI: 1.034-1.123), and therapeutic (HR 1.063, CI: 1.024-1.103) factors, PTT predicted mortality independently in patients with AL amyloidosis. Finally, PTT could identify worse outcomes in patients demonstrating New York Heart Association class III, Mayo 2004 stage III, and transmural LGE pattern. PTT may serve as a new imaging predictor of cardiac involvement and prognosis in AL amyloidosis. 2 TECHNICAL EFFICACY: Stage 2.

Shared and distinguishing phenotypic characteristics of filamin c and desmoplakin cardiomyopathy

Abstract Background Rare truncating variants in the genes Filamin C (FLNC) and Desmoplakin (DSP) are increasingly recognised causes of Dilated Cardiomyopathy and Arrhythmogenic Cardiomyopathy (1,2). A direct comparison of both genotypes is needed to aid in subclassification and genotype-specific risk modelling. Purpose We sought to identify shared and distinguishing clinical characteristics and imaging phenotypes between FLNC and DSP cardiomyopathy. Methods 41 patients with ‘pathogenic’ or ‘likely pathogenic’ FLNC or DSP variants by American College of Medical Genetics (ACMG) criteria were identified from a tertiary centre cardiovascular genetics laboratory. Clinical, genetic and imaging data were compiled. Continuous variables are presented as median [IQR] or mean±SD and analysed by nonparametric Mann Whitney U or t-test. Categorical variables were analysed by Chi-Squared or Fisher’s exact test. Results FLNC and DSP cohorts included a similar proportion of patients with truncating variants (91% vs 100%) and female sex (12/21, 57% vs 13/20, 65%). FLNC patients were younger (median age 30 [13-51] vs 57 [41-65] years, p&amp;lt;0.0008) and more likely to present with sustained ventricular arrhythmia (5/21 24% vs 3/20, 15%) (Table 1). Acute myocarditis episodes were exclusively linked to DSP cardiomyopathy (4/20, 20%) with no association to FLNC (0/21, 0%, p&amp;lt;0.05). FLNC cardiomyopathy patients had normal left ventricular (LV) systolic function (LVEF 57±9% SD vs 46±13% DSP, p&amp;lt;0.03) and normal left ventricular cavity side (mean indexed LV end diastolic volume (EDV) 85±12 vs 112±26ml/m2 DSP, p&amp;lt;0.02) (Table 2). Both FLNC and DSP cause exclusive left ventricular or biventricular late gadolinium enhancement (75% Vs 82%) on cardiac magnetic resonance imaging (MRI). Fibrosis was predominantly in a subepicardial distribution in both cohorts (66% FLNC vs 57% DSP). In FLNC, circumferential fibrosis was the most frequent pattern of distribution (5/9, 55%), whereas in DSP inferior and lateral wall fibrosis was the predominant feature (8/14, 57%). There were no cases of isolated RV involvement and no cases fulfilled ‘definite’ ARVC taskforce diagnostic criteria. Over a follow up of median 45months, there was no significant difference in the proportion of FLNC and DSP patients experiencing a composite end point of LVAD implantation, heart transplant, aborted sudden cardiac death or mortality (7/21, 33% FLNC Vs 7/20, 29% DSP p&amp;gt;0.99). Conclusion Normal systolic function with marked circumferential fibrosis is the predominant feature of FLNC cardiomyopathy whereas mild LV dilatation, mild systolic impairment and inferolateral fibrosis are more frequent in DSP cardiomyopathy. Myocarditis episodes are a distinguishing feature of DSP cardiomyopathy, suggesting a different underlying molecular mechanism driven by inflammation. The overall clinical trajectory of FLNC and DSP cardiomyopathy patients are comparable.

Image Characteristics of Virtual Non-Contrast Series Derived from Photon-Counting Detector Coronary CT Angiography-Prerequisites for and Feasibility of Calcium Quantification.

In photon-counting detector CT (PCD-CT), coronary artery calcium scoring (CACS) can be performed using virtual non-contrast (VNC) series derived from coronary CT angiography (CCTA) datasets. Our study analyzed image characteristics of VNC series in terms of the efficacy of virtual iodine "removal" and image noise to determine whether the prerequisites for calcium quantification were satisfied. We analyzed 38 patients who had undergone non-enhanced CT followed by CCTA on a PCD-CT. VNC reconstructions were performed at different settings and algorithms (conventional VNCConv; PureCalcium VNCPC). Virtual iodine "removal" was investigated by comparing histograms of heart volumes. Noise was assessed within the left ventricular cavity. Calcium was quantified on the true non-contrast (TNC) and all VNC series. The histograms were comparable for TNC and all VNC. Image noise between TNC and all VNC differed slightly but significantly. VNCConv CACS showed a significant underestimation regardless of the reconstruction setting, while VNCPC CACS were comparable to TNC. Correlations between TNC and VNC were excellent, with a higher predictive accuracy for VNCPC. In conclusion, the iodine contrast can be effectively subtracted from CCTA datasets. The remaining VNC series satisfy the requirements for CACS, yielding results with excellent correlation compared to TNC-based CACS and high predicting accuracy.

Abstract 16194: Relationship Between Change in Global Longitudinal Strain and Sustained Handgrip Induced Afterload as Assessed Using Invasive Left Ventricular Pressure Measurements and Machine Learning Analytics

Introduction: Global longitudinal strain (GLS) is a sensitive, quantitative measure of left ventricular (LV) systolic function and affected by afterload. We sought to compute the impact of LV systolic pressure (LVP) increase on GLS using handgrip stress during invasive LVP measurements. Methods: Patients undergoing left heart catheterization (n=51; mean age 64+/-11 years; 31% women; Table) for standard of care indications underwent echocardiography during handgrip stress with a catheter in the LV cavity. GLS and LVP were measured simultaneously over 15 seconds of continuous handgrip. GLS and LVP relationships were analyzed using linear regression and machine learning methods. Results: Sustained handgrip (HG) stress significantly increased LVP and reduced GLS. There was no significant correlation between resting and peak HG stress LVP and GLS (p= 0.32 &amp; 0.36, respectively). However, change in GLS was significantly correlated with change in LVP (p&lt;0.0001; Figure) with every 10 unit increase in LVP associated with a 0.6 reduction in GLS. The penalized maximum likelihood machine learning method was used to select key factors associated with the within subject slope of % change in GLS over % change in LVP (median slope -0.53; IQR-0.91 to -0.29). LV ejection fraction was identified as an important predictor of the GLS-LVP slope. LV ejection fraction was significantly associated with the slope (p=0.0005; Figure) with a 10 unit increase in LV ejection fraction corresponding to 0.22 increase in the slope. Conclusions: LV afterload is associated with significant decrements in GLS. LV ejection fraction is an important predictor of the GLS-LVP slope. These data provide the foundation to build models that would account for change in LVP during serial measurements of GLS thus allowing reliable comparison of repeated GLS measurements.

4Dimensional XStrain Echocardiography: Comprehensive Evaluation of Non-obstructive Hypertrophic Cardiomyopathy- A Case Report and Review of Literature

Hypertrophic cardiomyopathy (HCM) is a relatively common inherited cardiomyopathy, which is occasionally challenging to differentiate from hypertensive heart disease and athletes heart on the basis of morphologic or functional abnormalities alone. Imaging studies provide solution for majority of clinical presentations. Generally, transthoracic echocardiography (TTE) is employed as a first line imaging tool and contrast enhanced echocardiography (CEE), contrast tuned imaging echocardiography (CTIE), cardiac magnetic resonance (CMR), cardiac computed tomography (CCT), cardiac nuclear imaging and speckle tracking echocardiography (STE) are encouraged for either suboptimal studies because of poor visualization of left ventricular (LV) cavity or for comprehensive delineation of the cardiac anatomy, its widespread left and right ventricular involvement, associations and complications. We are reporting a case of 48-year old male presenting to us with atypical chest pain and a history of suspicious solitary episode of syncope. His routine ECG was indicative of left ventricular hypertrophy with strain pattern, and his TTE was substandard and inadequate in the apical four chamber (4CH) and five chamber (5CH) views, hence CTIE was performed without the application of intravenous contrast agents, to produce a remarkable illustration of HCM.&#x0D; Keywords: Hypertrophic cardiomyopathy, contrast echocardiography, contrast tuned imaging, speckle tracking echocardiography, 4Dimensional XStrain, Non obstructive HCM

Multimodality imaging in apical hypertrophic cardiomyopathy: clinical case

Apical hypertrophic cardiomyopathy is rare familial form of hypertrophic cardiomyopathy, with hypertrophy mainly affecting the apex of the left ventricle and characterized by a spade-like left ventricular cavity. Despite varying presentation, impaired capabilities of some standard instrumental methods and dissent on diagnostic criteria several diagnostic characteristics estimated by various noninvasive imaging modalities make it possible to establish a diagnosis with high accuracy. We hereby describe a case with electrocardiographic abnormalities and chest pain with suspected acute coronary syndrome. Acute coronary syndrome was excluded as well as performing invasive coronary angiography was avoided using advanced diagnostic tools including single photon emission computed tomography and apical hypertrophic cardiomyopathy was demonstrated by careful differential diagnosis.

The intraoperative visualisation technique during lead implantation into the cardiac conductive system: aspects of computed tomography: prospective study

INTRODUCTION: The lead implantation into the cardiac conduction system (CCS) is the most physiological method of pacing nowadays. «The method of intraoperative visualization and control of the lead position for permanent electrocardiostimulation during implantation of the lead in the CCS» has been developed for reduce the number of non-targeted implantations. This method based on the integration into the angiograph system 3D-reconstruction of the heart converted to computed tomography (CT) in the form of a mask against the background of fluoroscopy. CT is an important stage of the intraoperative visualization technique (IVT).OBJECTIVE: The aim of the study was to adapt the protocol of CT examination of the heart with contrast to construct a partially segmented 3D-reconstruction of the heart on an angiographic complex for subsequent use during of the lead implantation in the CCS within the framework of the author’s IVT.MATERIALS AND METHODS: As part of the development of the IVT, 21 CT studies of the heart were selected from own database. The step of the gradient of the density difference of the contrasted blood is about 10 HU, the range of the difference of densitometric parameters of the «left ventricle (LV) — right ventricle (RV)» from 0 HU to 200 HU. As well as selected 11 CT studies of the heart. The step of the gradient of the difference of densitometric indicators the contrasted blood in «the RV cavity — myocardium» is about 10 HU, the range is from 0 HU to 100 HU. All CT scans are alternately loaded into the angiograph, followed by the creation of a 3D model of the heart using basic software.RESULTS: It’s necessary to exceed the degree of contrast of the LV cavity over the RV cavity by at least 80 HU to perform partial segmentation on the left and right chambers of a 3D-model of the heart in an angiographic complex that does not have a specialized segmentation module. A sufficiently large part of the left ventricular cavity (LV) disappears with a smaller gradient when the right ventricular cavity (RV) is suppressed. The minimum gradient of «the ventricular cavity — myocardium» is at least 20 HU. The boundaries of the right ventricular edge of the interventricular septum (IVS) are not visualized with a smaller contrast gradient. It’s important for determining the insertion place of the lead into the IVS.CONCLUSION: It’s necessary to exceed the contrast of the LV cavities above the RV cavity by at least 80 HU, the RV cavity above the myocardium by at least 20 HU to perform partial segmentation on the left and right chambers of a 3D-model of the heart in an angiographic complex that does not have a specialized segmentation module