Artificial intelligence-based analysis of body composition predicts outcome in patients receiving long-term mechanical circulatory support

BACKGROUND

Obesity is a known cardiovascular risk factor and associated with higher postoperative complication rates in patients undergoing cardiac surgery. In heart failure (HF), conflicting evidence in terms of survival has been reported, whereas sarcopenia is associated with poor prognosis. An increasing number of HF patients require left ventricular assist device (LVAD) implantations. The postoperative mortality has improved in recent years but is still relatively high. The impact of body composition on outcome in this population remains unclear. The aim of this investigation was to examine the preoperative computed tomography (CT) body composition as a predictor of the postoperative outcome in advanced HF patients, who receive LVAD implantations.

METHODS

Preoperative CT scans of 137 patients who received LVADs between 2015 and 2020 were retrospectively analysed using an artificial intelligence (AI)-powered automated software tool based on a convolutional neural network, U-net, developed for image segmentation (Visage Version 7.1, Visage Imaging GmbH, Berlin, Germany). Assessment of body composition included visceral and subcutaneous adipose tissue areas (VAT and SAT), psoas and total abdominal muscle areas and sarcopenia (defined by lumbar skeletal muscle indexes). The body composition parameters were correlated with postoperative major complication rates, survival and postoperative 6-min walk distance (6MWD) and quality of life (QoL).

RESULTS

The mean age of patients was 58.21 ± 11.9 years; 122 (89.1%) were male. Most patients had severe HF requiring inotropes (Interagency Registry for Mechanically Assisted Circulatory Support [INTERMACS] profile I-III, 71.9%) secondary to coronary artery diseases or dilated cardiomyopathy (96.4%). Forty-four (32.1%) patients were obese (body mass index ≥ 30 kg/m2 ), 96 (70.1%) were sarcopene and 19 (13.9%) were sarcopene obese. Adipose tissue was associated with a significantly higher risk of postoperative infections (VAT 172.23 cm2 [54.96, 288.32 cm2 ] vs. 124.04 cm2 [56.57, 186.25 cm2 ], P = 0.022) and in-hospital mortality (VAT 168.11 cm2 [134.19, 285.27 cm2 ] vs. 135.42 cm2 [49.44, 227.91 cm2 ], P = 0.033; SAT 227.28 cm2 [139.38, 304.35 cm2 ] vs. 173.81 cm2 [97.65, 254.16 cm2 ], P = 0.009). Obese patients showed no improvement of 6MWD and QoL within 6 months postoperatively (obese: +0.94 ± 161.44 months, P = 0.982; non-obese: +166.90 ± 139.00 months, P < 0.000; obese: +0.088 ± 0.421, P = 0.376; non-obese: +0.199 ± 0.324, P = 0.002, respectively). Sarcopenia did not influence the postoperative outcome and survival within 1 year after LVAD implantation.

CONCLUSIONS

Preoperative AI-based CT body composition identifies patients with poor outcome after LVAD implantation. Greater adipose tissue areas are associated with an increased risk for postoperative infections, in-hospital mortality and impaired 6MWD and QoL within 6 months postoperatively.

Elastin stabilization prevents impaired biomechanics in human pulmonary arteries and pulmonary hypertension in rats with left heart disease

Pulmonary hypertension worsens outcome in left heart disease. Stiffening of the pulmonary artery may drive this pathology by increasing right ventricular dysfunction and lung vascular remodeling. Here we show increased stiffness of pulmonary arteries from patients with left heart disease that correlates with impaired pulmonary hemodynamics. Extracellular matrix remodeling in the pulmonary arterial wall, manifested by dysregulated genes implicated in elastin degradation, precedes the onset of pulmonary hypertension. The resulting degradation of elastic fibers is paralleled by an accumulation of fibrillar collagens. Pentagalloyl glucose preserves arterial elastic fibers from elastolysis, reduces inflammation and collagen accumulation, improves pulmonary artery biomechanics, and normalizes right ventricular and pulmonary hemodynamics in a rat model of pulmonary hypertension due to left heart disease. Thus, targeting extracellular matrix remodeling may present a therapeutic approach for pulmonary hypertension due to left heart disease.

Comparison of hemodynamics in biological surgical aortic valve replacement and transcatheter aortic valve implantation: An in-silico study

OBJECTIVES

In aortic valve replacement (AVR), the treatment strategy as well as the model and size of the implanted prosthesis have a major impact on the postoperative hemodynamics and thus on the clinical outcome. Preinterventional prediction of the hemodynamics could support the treatment decision. Therefore, we performed paired virtual treatment with transcatheter AVR (TAVI) and biological surgical AVR (SAVR) and compared hemodynamic outcomes using numerical simulations.

METHODS

10 patients with severe aortic stenosis (AS) undergoing TAVI were virtually treated with both biological SAVR and TAVI to compare post-interventional hemodynamics using numerical simulations of peak-systolic flow. Virtual treatment procedure was done using an in-house developed tool based on position-based dynamics methodology, which was applied to the patient's anatomy including LVOT, aortic root and aorta. Geometries were automatically segmented from dynamic CT-scans and patient-specific flow rates were calculated by volumetric analysis of the left ventricle. Hemodynamics were assessed using the STAR CCM+ software by solving the RANS equations.

RESULTS

Virtual treatment with TAVI resulted in realistic hemodynamics comparable to echocardiographic measurements (median difference in transvalvular pressure gradient [TPG]: -0.33 mm Hg). Virtual TAVI and SAVR showed similar hemodynamic functions with a mean TPG with standard deviation of 8.45 ± 4.60 mm Hg in TAVI and 6.66 ± 3.79 mm Hg in SAVR (p = 0.03) while max. Wall shear stress being 12.6 ± 4.59 vs. 10.2 ± 4.42 Pa (p = 0.001).

CONCLUSIONS

Using the presented method for virtual treatment of AS, we were able to reliably predict post-interventional hemodynamics. TAVI and SAVR show similar hemodynamics in a pairwise comparison.

3D modeling and printing for complex biventricular repair of double outlet right ventricle

BACKGROUND

Double outlet right ventricle (DORV) describes a group of congenital heart defects where pulmonary artery and aorta originate completely or predominantly from the right ventricle. The individual anatomy of DORV patients varies widely with multiple subtypes classified. Although the majority of morphologies is suitable for biventricular repair (BVR), complex DORV anatomy can render univentricular palliation (UVP) the only option. Thus, patient-specific decision-making is critical for optimal surgical treatment planning. The evolution of image processing and rapid prototyping techniques facilitate the generation of detailed virtual and physical 3D models of the patient-specific anatomy which can support this important decision process within the Heart Team.

MATERILAS AND METHODS

The individual cardiovascular anatomy of nine patients with complex DORV, in whom surgical decision-making was not straightforward, was reconstructed from either computed tomography or magnetic resonance imaging data. 3D reconstructions were used to characterize the morphologic details of DORV, such as size and location of the ventricular septal defect (VSD), atrioventricular valve size, ventricular volumes, relationship between the great arteries and their spatial relation to the VSD, outflow tract obstructions, coronary artery anatomy, etc. Additionally, physical models were generated. Virtual and physical models were used in the preoperative assessment to determine surgical treatment strategy, either BVR vs. UVP.

RESULTS

Median age at operation was 13.2 months (IQR: 9.6-24.0). The DORV transposition subtype was present in six patients, three patients had a DORV-ventricular septal defect subtype. Patient-specific reconstruction was feasible for all patients despite heterogeneous image quality. Complex BVR was feasible in 5/9 patients (55%). Reasons for unsuitability for BVR were AV valve chordae interfering with potential intraventricular baffle creation, ventricular hypoplasia and non-committed VSD morphology. Evaluation in particular of qualitative data from 3D models was considered to support comprehension of complex anatomy.

CONCLUSION

Image-based 3D reconstruction of patient-specific intracardiac anatomy provides valuable additional information supporting decision-making processes and surgical planning in complex cardiac malformations. Further prospective studies are required to fully appreciate the benefits of 3D technology.

Artificial intelligence-based body composition predicts postoperative complications and mortality in advanced heart failure patients receiving long-term mechanical circulatory support

Background

Obesity is an independent cardiovascular risk factor and is associated with higher postoperative infection rates in patients after cardiac surgery. However, in heart failure, obesity has been described as beneficial in terms of survival (“obesity paradox”); whereas sarcopenia is associated with poor prognosis. An increasing number of advanced heart failure patients requires surgical treatment in terms of left ventricular assist device (LVAD) implantation. The postoperative in-hospital survival has improved in recent years but is still relatively high (11.1%). The impact of body composition on outcome in this population remains unclear.

Purpose

The aim of this investigation was to examine the preoperative computed tomography (CT) body composition based on artificial intelligence (AI) analysis as a predictor of the postoperative outcome in advanced heart failure patients, who underwent LVAD implantation.

Methods

Preoperative CT scans of 137 patients who received LVAD implantations between 2015 and 2020 were retrospectively analyzed using an AI-powered automated software tool based on a convolutional neural network, U-net, developed for image segmentation (Visage version 7.1., Visage Imaging GmbH, Berlin, Germany; Figure 1). Assessment of body composition included visceral and subcutaneous adipose tissue areas (VAT, SAT), psoas and total abdominal muscle areas (PMA, TAMA) and sarcopenia (defined as lumbal skeletal muscle index ≤38.5 cm2/m2 in women and ≤54.4 cm2/m2 in men). The body composition parameters were correlated with postoperative major complication rates and survival.

Results

The mean age of patients was 58.21±11.9 years; 122 (89.1%) were male. Most patients had severe heart failure requiring inotropes (INTERMACS profile I-III, 71.9%) secondary to coronary artery diseases or dilated cardiomyopathy (96.4%). 44 (32.1%) patients were obese (BMI ≥30 kg/m2), 96 (70.1%) were sarcopene and 19 (13.9%) were sarcopene obese. Adipose tissue was associated with a significantly higher risk of overall postoperative complications (SAT 158.22 cm2 [63.09, 256.78 cm2] vs. 124.04 cm2 [42.86, 187.68 cm2], p=0.049) and in-hospital mortality (VAT 168.11 cm2 [134.19, 285.27 cm2] vs. 135.42 cm2 [49.44, 227.91 cm2], p=0.033; SAT 227.28 cm2 [139.38, 304.35 cm2] vs. 173.81 cm2 [97.65, 254.16 cm2], p=0.009). Sarcopenia did not influence the postoperative outcome and survival within 1 year post LVAD implantation.

Conclusions

Preoperative AI-based CT body composition identifies patients with poor prognosis after LVAD implantation. Adipose tissue areas predict in-hospital mortality, thus, obesity as a perioperative risk factor outweighs the protective effect known in heart failure patients when undergoing LVAD implantation.

Funding Acknowledgement

Type of funding sources: None.

Virtual treatment planning in three patients with univentricular physiology using computational fluid dynamics—Pitfalls and strategies

Background

Uneven hepatic venous blood flow distribution (HFD) to the pulmonary arteries is hypothesized to be responsible for the development of intrapulmonary arteriovenous malformations (PAVM) in patients with univentricular physiology. Thus, achieving uniform distribution of hepatic blood flow is considered favorable. However, no established method for the prediction of the post-interventional hemodynamics currently exists. Computational fluid dynamics (CFD) offers the possibility to quantify HFD in patient-specific anatomies before and after virtual treatment. In this study, we evaluated the potential benefit of CFD-assisted treatment planning.

Materials and methods

Three patients with total cavopulmonary connection (TCPC) and PAVM underwent cardiovascular magnetic resonance imaging (CMR) and computed tomography imaging (CT). Based on this imaging data, the patient-specific anatomy was reconstructed. These patients were considered for surgery or catheter-based intervention aiming at hepatic blood flow re-routing. CFD simulations were then performed for the untreated state as well as for different surgical and interventional treatment options. These treatment options were applied as suggested by treating cardiologists and congenital heart surgeons with longstanding experience in interventional and surgical treatment of patients with univentricular physiology. HFD was quantified for all simulations to identify the most viable treatment decision regarding redistribution of hepatic blood flow.

Results

For all three patients, the complex TCPC anatomy could be reconstructed. However, due to the presence of metallic stent implants, hybrid models generated from CT as well as CMR data were required. Numerical simulation of pre-interventional HFD agreed well with angiographic assessment and physiologic considerations. One treatment option resulting in improvement of HFD was identified for each patient. In one patient follow-up data after treatment was available. Here, the virtual treatment simulation and the CMR flow measurements differed by 15%.

Conclusion

The combination of modern computational methods as well as imaging methods for assessment of patient-specific anatomy and flow might allow to optimize patient-specific therapy planning in patients with pronounced hepatic flow mismatch and PAVM. In this study, we demonstrate that these methods can also be applied in patients with complex univentricular physiology and extensive prior interventions. However, in those cases, hybrid approaches utilizing information of different image modalities may be required.

CT-Based Analysis of Left Ventricular Hemodynamics Using Statistical Shape Modeling and Computational Fluid Dynamics

Background

Cardiac computed tomography (CCT) based computational fluid dynamics (CFD) allows to assess intracardiac flow features, which are hypothesized as an early predictor for heart diseases and may support treatment decisions. However, the understanding of intracardiac flow is challenging due to high variability in heart shapes and contractility. Using statistical shape modeling (SSM) in combination with CFD facilitates an intracardiac flow analysis. The aim of this study is to prove the usability of a new approach to describe various cohorts.

Materials and Methods

CCT data of 125 patients (mean age: 60.6 ± 10.0 years, 16.8% woman) were used to generate SSMs representing aneurysmatic and non-aneurysmatic left ventricles (LVs). Using SSMs, seven group-averaged LV shapes and contraction fields were generated: four representing patients with and without aneurysms and with mild or severe mitral regurgitation (MR), and three distinguishing aneurysmatic patients with true, intermediate aneurysms, and globally hypokinetic LVs. End-diastolic LV volumes of the groups varied between 258 and 347 ml, whereas ejection fractions varied between 21 and 26%. MR degrees varied from 1.0 to 2.5. Prescribed motion CFD was used to simulate intracardiac flow, which was analyzed regarding large-scale flow features, kinetic energy, washout, and pressure gradients.

Results

SSMs of aneurysmatic and non-aneurysmatic LVs were generated. Differences in shapes and contractility were found in the first three shape modes. Ninety percent of the cumulative shape variance is described with approximately 30 modes. A comparison of hemodynamics between all groups found shape-, contractility- and MR-dependent differences. Disturbed blood washout in the apex region was found in the aneurysmatic cases. With increasing MR, the diastolic jet becomes less coherent, whereas energy dissipation increases by decreasing kinetic energy. The poorest blood washout was found for the globally hypokinetic group, whereas the weakest blood washout in the apex region was found for the true aneurysm group.

Conclusion

The proposed CCT-based analysis of hemodynamics combining CFD with SSM seems promising to facilitate the analysis of intracardiac flow, thus increasing the value of CCT for diagnostic and treatment decisions. With further enhancement of the computational approach, the methodology has the potential to be embedded in clinical routine workflows and support clinicians.

Surgical Restoration of Antero-Apical Left Ventricular Aneurysms: Cardiac Computed Tomography for Therapy Planning

Background

Surgical ventricular restoration (SVR) leads to functional improvement by volume reduction and restoration of left ventricular (LV) geometry. Our purpose was to refine the planning for SVR using cardiac computed tomography (CCT).

Methods

The possibility to anticipate the postoperative residual LV volume was assessed using CCT in 205 patients undergoing SVR combined with coronary artery bypass grafting (77%), mitral valve repair/replacement (19%) and LV thrombectomy (19%). The potential of CCT to guide the procedure was evaluated. Additionally, the predictive value of CCT characteristics on survival was addressed.

Results

30-day, 1- and 5-year survival was 92.6, 82.7, and 72.1%, respectively, with a marked reduction of NYHA class III-IV quota after surgery (95.1% vs. 20.5% in the follow-up). Both pre- and postoperative LV end-systolic volume index (LVESVI) were predictive of all defined endpoints according to the following tertiles: preoperative: <74 ml/m², 74–114 ml/m² and >114 ml/m²; postoperative: <58 ml/m², 58–82 ml/m² and >82 ml/m². On average, a 50 ml/m² increase of preoperative LVESVI was associated with a 35% higher hazard of death (p = 0.043). Aneurysms limited to seven antero-apical segments (1–7) were associated with a lower death risk (n = 60, HR 0.52, CI 0.28–0.96, p = 0.038). LVESVI predicted by CCT was found to correlate significantly with effectively achieved LVESVI (r = 0.87 and r = 0.88, respectively, p < 0.0001).

Conclusions

CCT-guided SVR can be performed with good mid-term survival and significant improvement in HF severity. CCT-based assessment of achievable postoperative LV volume helps estimate the probability of therapeutic success in individual patients.

CT-Based Simulation of Left Ventricular Hemodynamics: A Pilot Study in Mitral Regurgitation and Left Ventricle Aneurysm Patients

Background

Cardiac CT (CCT) is well suited for a detailed analysis of heart structures due to its high spatial resolution, but in contrast to MRI and echocardiography, CCT does not allow an assessment of intracardiac flow. Computational fluid dynamics (CFD) can complement this shortcoming. It enables the computation of hemodynamics at a high spatio-temporal resolution based on medical images. The aim of this proposed study is to establish a CCT-based CFD methodology for the analysis of left ventricle (LV) hemodynamics and to assess the usability of the computational framework for clinical practice.

Materials and Methods

The methodology is demonstrated by means of four cases selected from a cohort of 125 multiphase CCT examinations of heart failure patients. These cases represent subcohorts of patients with and without LV aneurysm and with severe and no mitral regurgitation (MR). All selected LVs are dilated and characterized by a reduced ejection fraction (EF). End-diastolic and end-systolic image data was used to reconstruct LV geometries with 2D valves as well as the ventricular movement. The intraventricular hemodynamics were computed with a prescribed-motion CFD approach and evaluated in terms of large-scale flow patterns, energetic behavior, and intraventricular washout.

Results

In the MR patients, a disrupted E-wave jet, a fragmentary diastolic vortex formation and an increased specific energy dissipation in systole are observed. In all cases, regions with an impaired washout are visible. The results furthermore indicate that considering several cycles might provide a more detailed view of the washout process. The pre-processing times and computational expenses are in reach of clinical feasibility.

Conclusion

The proposed CCT-based CFD method allows to compute patient-specific intraventricular hemodynamics and thus complements the informative value of CCT. The method can be applied to any CCT data of common quality and represents a fair balance between model accuracy and overall expenses. With further model enhancements, the computational framework has the potential to be embedded in clinical routine workflows, to support clinical decision making and treatment planning.

Predictive Value of Two-Dimensional Speckle-Tracking Echocardiography in Patients Undergoing Surgical Ventricular Restoration

Objectives

Parameters of left ventricular (LV) mechanics, obtained from speckle-tracking echocardiography (STE), were found to be of prognostic value in patients with heart failure and those who underwent cardiac surgery. This study aimed to assess the value of STE in patients scheduled to undergo surgical ventricular restoration (SVR).

Methods

A total of 158 consecutive patients with baseline STE who underwent SVR due to an LV anteroapical aneurysm were included in the analysis. Preoperative longitudinal STE parameters were evaluated for their association with an outcome, defined as all-cause mortality, LV assist device implantation, or heart transplantation. The echocardiographic follow-up to assess the change in the regional function of the segments remote from the aneurysm was performed in 43 patients at a median of 10 months [interquartile range (IQR): 6–12.7 months] after SVR.

Results

During a median follow-up of 5.1 years (IQR: 1.6–8.7 years), events occurred in 68 patients (48%). Less impaired mean basal end-systolic longitudinal strain (BLS) with a cutoff value ≤ −10.1 % demonstrated a strong association with event-free survival, also in patients with an LV shape corresponding to an intermediate shape between aneurysmal and globally akinetic. Initially hypo- or akinetic basal segments with preoperative end-systolic strain ≤ −7.8% showed a greater improvement in wall motion at the short-term follow up.

Conclusion

Patients with less impaired preoperative BLS exhibited a better event-free survival after SVR, also those with severe LV remodeling. The preserved preoperative segmental longitudinal strain was associated with a greater improvement in regional wall motion after SVR. BLS assessment may play a predictive role in patients with an LV anteroapical aneurysm who are scheduled to undergo SVR.

The value of diastolic speckle-tracking parameters in predicting outcome after surgical ventricular restoration

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): DZHK (German Centre for Cardiovascular Research) BMBF (German Ministry of Education and Research)

Background. Parameters of speckle-tracking echocardiography (STE) are incorporated into the integrative assessment of left ventricular (LV) diastolic function 1. In this study we aimed to evaluate both established and novel STE parameters of LV diastolic function and their prognostic role in patients with LV anteroapical aneurysm planned for surgical ventricular restoration (SVR).

Methods. We retrospectively examined data of 137 patients (60 ± 11 years, 25% women) with anteroapical LV aneurysm who underwent SVR and for whom preoperative echocardiography was available and feasible for STE and for conventional assessment of LV diastolic function by transmitral flow. STE parameters evaluated were: left atrial reservoir strain (LAS), early and late global diastolic strain rate (GLSRe and GLSRa), ratio of early-to-late diastolic strain rate (GLSRe/GLSRa), and ratio of early diastolic transmitral flow velocity (E) to GLSRe and to GLSRa. In 24 patients we evaluated an association of diastolic echocardiographic parameters with mean pulmonary artery pressure (PAPm) and mean pulmonary capillary wedge pressure (PCWPm) obtained invasively within 6 days of echocardiography. Preoperative echocardiographic parameters were assessed in whole cohort of patients for the association with an outcome, defined as all-cause mortality, LV assist device implantation, or heart transplantation.

Results. During a median follow-up of 4.7 years (IQR: 1.4-8.1 years) events occurred in 59 patients. GLSRa, E/GLSRa and LAS demonstrated significant correlation with PAPm and PCWPm (Table 1). GLSRa with optimal cut-off value of ≤ 0.41 s-1 was able to detect PAPm &gt;30 mmHg with sensitivity of 0.8 and specificity of 0.8 (AUC 0.85; 95% CI 0.68-1.0; p = 0.008). E/GLSRa ≥1.24 m was able to detect PAPm &gt;30 mmHg with sensitivity of 1.0 and specificity of 0.8 (AUC 0.87; 95%CI 0.7-1.0; p = 0.005). There was significant difference in event-free survival between groups stratified by cut-offs for GLSRa (Fig. 1A) and E/GLSRa (Fig. 1B). After adjustment for important clinical (age, sex, plasma creatinine, atrial fibrillation) and echocardiographic parameters (fractional shortening and LV end-systolic volume index) GLSRa and E/GLSRa remained an independent predictors of events (HR 0.16; 95% CI: 0.03-0.86; p = 0.032 and HR 1.22; 95% CI: 1.03-1.43; p = 0.018) and demonstrated higher prognostic value compared to LAS, other STE parameters and conventional parameters of LV diastolic function.

Conclusion. Late diastolic longitudinal strain rate and ratio of early diastolic transmitral flow velocity to late diastolic longitudinal strain rate demonstrated association with hemodynamic parameters in patients with LV anteropaical aneurysm and might be used for the evaluation of LV diastolic function. These parameters showed prognostic value for patients underwent SVR and could be implemented for preoperative evaluation of these patients. Abstract Table 1. Correlation data  Abstract Figure 1. Survival curves

Comparison of feasibility and results of frailty assessment methods prior to left ventricular assist device implantation

AIMS

Assessing frailty and sarcopenia is considered a valuable cornerstone of perioperative risk stratification in advanced heart failure patients. The lack of an international consensus on a diagnostic standard impedes its implementation in the clinical routine. This study aimed to compare the feasibility and prognostic impact of different assessment tools in patients undergoing continuous-flow left ventricular assist device (cf-LVAD) implantation.

METHODS AND RESULTS

We prospectively compared feasibility and prognostic values of six frailty/sarcopenia assessment methods in 94 patients prior to cf-LVAD implantation: bioelectrical impedance analysis (BIA), computed tomography (CT)-based measurement of two muscle areas/body surface area [erector spinae muscle (TMESA/BSA) and iliopsoas muscle (TPA/BSA)], physical performance tests [grip strength, 6 min walk test (6MWT)] and Rockwood Clinical Frailty Scale (RCFS). Six-month mortality and/or prolonged ventilation time >95 h was defined as the primary endpoint. BIA and CT showed full feasibility (100%); physical performance and RCFS was limited due to patients' clinical status (feasibility: 87% grip strength, 62% 6MWT, 88% RCFS). Phase angle derived by BIA showed the best results regarding the prognostic value for 6 month mortality and/or prolonged ventilation time >95 h (odds ratio (OR) 0.66 [95% confidence interval (CI): 0.46-0.92], P = 0.019; area under the curve (AUC) 0.65). It provided incremental value to the clinical risk assessment of EuroSCORE II: C-index of the combined model was 0.75 [95% CI; 0.651-0.848] compared with C-index of EuroSCORE II alone, which was 0.73 (95% CI: 0.633-0.835). Six-month survival was decreased in patients with reduced body cell mass derived by BIA or reduced muscle area in the CT scan compared with patients with normal values: body cell mass 65% (95% CI: 51.8-81.6%) vs. 83% (95% CI: 74.0-93.9%); P = 0.03, TMESA/BSA 65% (95% CI: 51.2-82.2%) vs. 82% (95% CI: 73.2-93.0%); P = 0.032 and TPA/BSA 66% (95% CI: 53.7-81.0%) vs. 85% (95% CI: 75.0-95.8%); P = 0.035.

CONCLUSIONS

Bioelectrical impedance analysis parameters and CT measurements were shown to be suitable to predict 6-month mortality and/or prolonged ventilation time >95 h in patients with advanced heart failure prior to cf-LVAD implantation. Phase angle had the best predictive capacity and sarcopenia diagnosed by reduced body cell mass in BIA or muscle area in CT was associated with a decreased 6 month survival.

Impact of Muscle Mass as a Prognostic Factor for Failed Waiting Time Prior to Heart Transplantation

Objectives: Clinical deterioration during the waiting time impairs the prognosis of patients listed for heart transplantation. Reduced muscle mass increases the risk for mortality after cardiac surgery, but its impact on resilience against deterioration during the waiting time remains unclear.

Methods: We retrospectively analyzed data from 93 patients without a VAD who were listed in Eurotransplant status “high urgent (HU)” for heart transplantation between January 2015 and October 2020. The axial muscle area of the erector spinae muscles at the level of thoracic vertebra 12 indexed to body surface area (TMESA/BSA) measured in the preoperative thoracic computed tomography scan was used to measure muscle mass.

Results: Forty patients (43%) underwent emergency VAD implantation during the waiting time and four patients (4%) died during the waiting time. The risk of emergency VAD implantation/death during the waiting time decreased by 10% for every cm²/m² increase in muscle area [OR 0.901 (95% CI: 0.808–0.996); p = 0.049]. After adjusting for gender [OR 0.318 (95% CI: 0.087–1.073); p = 0.072], mean pulmonary artery pressure [OR 1.061 (95% CI: 0.999–1.131); p = 0.060], C-reactive protein [OR 1.352 (95% CI: 0.986–2.027); p = 0.096], and hemoglobin [OR 0.862 (95% CI: 0.618–1.177); p = 0.360], TMESA/BSA [OR 0.815 (95% CI: 0.698–0.936); p = 0.006] remained an independent risk factor for emergency VAD implantation/death during the HU waiting time.

Conclusion: Muscle area of the erector spinae muscle appears to be a potential, easily identifiable risk factor for emergency VAD implantation or death in patients on the HU waiting list for heart transplantation. Identifying patients at risk could help optimize the outcome and the timing of VAD support.

Surgical ventricular reconstruction eligible for late assist device implantation

In patients with ischemic cardiomyopathy and left ventricular aneurysm formation that are symptomatic despite optimal medical therapy it is challenging to determine whether surgical ventricular reconstruction (SVR), heart transplantation, or left ventricular assist device (LVAD) implantation is the treatment of choice. In this report, we present the novel concept of SVR with a specially prepared LVAD fixation ring to facilitate subsequent LVAD implantation if required. In our case endoventricular circular LVAD ring plasty sufficiently reduced the ventricular volume, normalized the left ventricular geometry and subsequently led to an improvement of left ventricular ejection fraction.

Computed Tomography-Based Assessment of Transvalvular Pressure Gradient in Aortic Stenosis

Background: In patients with aortic stenosis, computed tomography (CT) provides important information about cardiovascular anatomy for treatment planning but is limited in determining relevant hemodynamic parameters such as the transvalvular pressure gradient (TPG).

Purpose: In the present study, we aimed to validate a reduced-order model method for assessing TPG in aortic stenosis using CT data.

Methods: TPG_CT was calculated using a reduced-order model requiring the patient-specific peak-systolic aortic flow rate (Q) and the aortic valve area (AVA). AVA was determined by segmentation of the aortic valve leaflets, whereas Q was quantified based on volumetric assessment of the left ventricle. For validation, invasively measured TPG_catheter was calculated from pressure measurements in the left ventricle and the ascending aorta. Altogether, 84 data sets of patients with aortic stenosis were used to compare TPG_CT against TPG_catheter.

Results: TPG_catheter and TPG_CT were 50.6 ± 28.0 and 48.0 ± 26 mmHg, respectively (p = 0.56). A Bland–Altman analysis revealed good agreement between both methods with a mean difference in TPG of 2.6 mmHg and a standard deviation of 19.3 mmHg. Both methods showed good correlation with r = 0.72 (p < 0.001).

Conclusions: The presented CT-based method allows assessment of TPG in patients with aortic stenosis, extending the current capabilities of cardiac CT for diagnosis and treatment planning.

Percutaneous mitral valve repair assisted by a catheter-based circulatory support device in a heart transplant patient

BACKGROUND

Systemic infections and chronic graft rejection represent common causes of mortality and morbidity in heart transplant patients. In severe cases, cardiogenic shock (CS) may occur and require hemodynamic stabilization with temporary mechanical circulatory support (tempMCS). Under these devastating circumstances, treatment of sequelae of left ventricular dysfunction, such as secondary mitral regurgitation (MR) is challenging, especially when surgical repair is deemed futile. In nontransplant patients, interventional mitral valve repair strategies such as the MitraClip system (Abbott Cardiovascular) have been used to successfully treat secondary MR and allow for weaning from tempMCS.

CASE SUMMARY

We report about the first patient in whom profound CS after heart transplantation was stabilized with tempMCS followed by interventional elimination of secondary MR.

A new calcium score to predict paravalvular leak in transcatheter aortic valve implantation

OBJECTIVES

The present study sought to develop a reliable calcium score (Ca-score) to predict paravalvular leak (PVL) in patients undergoing transcatheter aortic valve (AV) implantation.

METHODS

A total of 965 patients were prospectively included from 2012 to 2019. Preprocedural contrast-media-enhanced computed tomography scans were analysed regarding the amount of AV cusp calcification and the presence of upper and lower left ventricular outflow tract calcification. The calcium volume threshold of each AV cusp [non-coronary cusp (NCC); left coronary cusp (LCC); right coronary cusp (RCC)] with optimal PVL prediction was defined using the Youden index value derived from receiver operating characteristic analysis. The final score was developed based on the multivariable regression analysis, while individual variables were weighted based on their corresponding odds ratio.

RESULTS

The AV calcium volume threshold with optimal PVL prediction was 733.6, 296.0 and 131.2 mm3 for the NCC, RCC and LCC respectively. Overall, calcification of the upper left ventricular outflow tract was present in 233 (23%), 111 (12%) and 304 (32%) of patients below the NCC, RCC and LCC respectively, while 260 (27%), 44 (5%) and 217 (23%) patients suffered from calcification under the NCC, RCC and LCC, respectively. A total Ca-score of ≥4 was present in 356 (37%) of patients and was independently associated with ≥ mild PVL [odds ratio 3.662; 95% confidence interval (2.740-4.911); P < 0.001]. The area under the curve of the Ca-score was 0.713 [95% confidence interval (0.678-0.748); P < 0.001].

CONCLUSION

The provided Ca-score independently correlates with the development of PVL and improves risk stratification in patients undergoing transcatheter AV implantation.

Feasibility of two-dimensional speckle-tracking echocardiography of aortic valve in patients with calcific aortic valve disease

Calcific aortic valve (AV) disease is associated with increased stiffness and reduced motion of AV leaflets, has a progressive course, and can develop into aortic stenosis (AS). Our aim was to evaluate whether two-dimensional speckle-tracking echocardiography (STE) may be used for the assessment of AV stiffness. We applied STE to AV leaflets in patients with various degrees of degenerative changes of AV and measured strain as an absolute value of the radial deformation of AV leaflets. Deformation of AV expressed as averaged AV strain was greatest in patients with a normal AV (23.4 ± 6.4%), compared to those with aortic sclerosis (12.9 ± 3.2%), moderate-to-severe AS (11.9 ± 4%), and severe AS (10.9 ± 3.5%) (p < 0.01). A non-linear relationship and moderate correlation of AV strain with transvalvular hemodynamic parameters was observed. In patients with mild-to-moderate AS, the strain of AV leaflets also correlated negatively with AV calcification (r = -0.59, p = 0.008). Good inter-observer agreement was obtained for averaged AV strain with a coefficient of variation of 0.15 and an interclass correlation coefficient of 0.94 (p < 0.0001). In this study we demonstrated that deformation of AV leaflets as assessed by STE might be a potential method for a non-invasive evaluation of AV biomechanical properties and of the progression of calcific aortic disease. Further development of the two-dimensional speckle tracking technique specifically for valve structures is needed to enable a better quantification of leaflet deformation.

Cardiac computed tomography for therapy targeting in surgical repair of anteroapical left ventricular aneurysms: assessment of aneurysm volume and of anticipated residual left ventricular volume

Funding Acknowledgements

Type of funding sources: None.

Background

Surgical ventricular repair (SVR) is an established treatment option in patients with heart failure (HF) due to left ventricular (LV) aneurysms, whereby LV volume reduction is the principal therapeutic target. Precise planning therefore is essential for postoperative improvement of HF symptoms.

Purpose

In this study we evaluated the potential of cardiac computed tomography (CCT) to estimate the aneurysm volume and to predict the achievable residual LV volume.

Methods

 205 patients (11/2005-01/2016, m:w = 151:54, median 63.4 years; mean NYHA class 3.03) with anteroapical LV aneurysm underwent SVR combined with coronary artery bypass grafting (77%), mitral valve repair/replacement (19%), and LV thrombectomy (19%). CCT was performed before and 7 days after surgery. Volumetric assessment was made using dedicated software (syngo.via Cardiac Function, Siemens AG).  Preoperative CCT data of 48 consecutive patients were analyzed and then matched with effectively achieved postoperative volumes. To separate the aneurysm volume in the systole and diastole a plane determined by three landmarks on borders of scared to intact LV myocardium (antero-septal, lateral and inferior) was used. In this way ensued the retrospective estimation of the aneurysm volume (AnV/AnVI) and anticipated LV end diastolic and end systolic volume (LVEDVI, LVESVI).

Results

Mean diastolic and systolic estimated AnV were 92 ± 56.6 ml and 83.5 ± 61.6 ml respectively. Relation of AnV to LVEDV and to LVESV was 29.2% and 38.2%, correspondingly. There was significant correlation between anticipated and effectively achieved LVEDV and LVESV (r = 0.87 and r = 0.88, respectively, p &lt; 0.0001), and their indexed values (r = 0.83 and r = 0.83, respectively, p &lt; 0.0001). Anticipated LVEDVI was only 10.3 ± 22.5 ml/m2 greater than achieved LVEDVI (p = 0.003), and anticipated LVESVI was only 2.4 ± 20.3 ml/m2 greater than achieved LVESVI (p = 0.433).

Conclusions

Estimation of aneurysm volume and anticipated postoperative LV volume allows to predict if the therapeutic targets can be successfully achieved in individual patients. Based on the CCT assessment we propose an approach for surgical planning in anterior LV aneurysms.

Two-dimensional echocardiography compared to cardiac computed tomography for assessment of left ventricular volume and function in patients with anteroapical aneurysm

Funding Acknowledgements

Type of funding sources: None.

Background. Two-dimensional (2D) echocardiography is widely accepted method for the assessment of left ventricular (LV) morphology and function after myocardial infarction and for initial preoperative evaluation of patients planned for surgical ventricular repair (SVR). Magnetic resonance imaging and cardiac computer tomography (CT) provide more accurate measurements, but not always available.

Purpose. The aim of this study was to compare 2D-echocardiography and CT for preoperative assessment of patients with LV aneurysm in order to optimize the perioperative management in SVR.

Methods. Patients (n = 179, mean age 62.6 ± 11 years, 23.5% women) with LV anteroapical aneurysm due to myocardial infarction were examined by echocardiography and CT before SVR. LV end-diastolic and end-systolic volumes (LVEDV and LVESV) and ejection fraction (EF) obtained by two methods were compared pairwise. Prognostic role for the prediction of all-cause death was assessed for preoperative parameters in multivariate Cox regression model adjusted for patient age, sex, NYHA class, diabetes mellitus, renal failure, atrial fibrillation and arterial hypertension.

Results. There was a strong correlation for preoperative LVEDV and LVESV measured by echocardiography and CT (r = 0.85, r = 0.87, p &lt; 0.0001), however volumes obtained by echocardiography were smaller compared to those by CT (Table) with higher difference in patients with more dilated LV, as demonstrated by Bland-Altman analysis (Fig.). No significant difference in mean preoperative EF was observed with moderate correlation between two methods (r = 0.67, p &lt; 0.0001). In total 68 patients died during median follow up of 5.3 years (IQR: 1.7-8.7 years) after SVR. Comparable predictive value was demonstrated for LVEDV measured by CT and echocardiography (for 10 ml increase HR = 1.04, p = 0.004 and HR = 1.06, p = 0.0001), as well as for LVESV (for 10 ml increase HR = 1.04, p = 0.001 and HR = 1.07, p = 0.0001) and for EF (for 5% increase HR = 0.83, p = 0.004 and HR = 0.81, p = 0.004).

Conclusion. In patients with LV aneurysm 2D-echocardiography may be used for the assessment of LV volumes and function and have similar prognostic role compared to CT in patients evaluated for SVR. Underestimation of LV volumes by echocardiography must be considered, especially in patients with more dilated LV.

Comparison of CT and echocardiography Parameter CT Echo Mean difference p-value LVEDV, ml LVESV, ml EF, % 289 ± 104 198 ± 97 34 ± 12 222 ± 81 149 ± 67 35 ± 9 67 ± 56 49 ± 51 -0.9 ± 9.2 &lt;0.0001 &lt;0.0001 0.215 Abstract Figure. Bland-Altman plots for LVEDV and LVESV

Minimally invasive left ventricular reconstruction of a postinfarction, anterior left ventricular scar (BioVentrix Revivent TC procedure)

Surgical ventricular reconstruction is a proven option for treating patients who have heart failure due to a postinfarction scar or an aneurysm of the left ventricle. The BioVentrix Revivent TC System offers a reliable alternative to the conventional, more invasive surgical ventricular restoration. The system requires no sternotomy, no heart-lung machine, and no cardioplegic arrest.  In this video tutorial, we present our technique for using the Revivent TC System to reconstruct the normal left ventricular shape and volume in a patient with a postinfarction, anteroapical scar.

Prognostic role of left ventricular diastolic function assessed by speckle tracking echocardiography in patients after surgical ventricular repair

Background

Assessment of left ventricular (LV) diastolic function brings important prognostic information for patients with heart failure and could be evaluated by speckle tracking echocardiography (STE). Less known about its role in patients planned for surgical ventricular repair due to LV aneurysm.

Purpose

The aim of this study was to evaluate the prognostic role of STE parameters of LV diastolic function for prediction of all-cause mortality in patients after surgical ventricular repair.

Methods

We retrospectively evaluated data of 163 consecutive pts (mean age 62.3±11.5 years, 74.8% males) with anteroapical LV aneurysm who underwent surgical ventricular repair combined with coronary artery bypass surgery (71.8%) Prognostic role for prediction of all-cause mortality was assessed for various STE parameters, including left atrial strain (LAS) measured as peak reservoir strain and for the ratio of early to late global longitudinal strain rate (GLSRe/GLSRa).

Results

During a median follow-up of 4.7 years (IQR: 1.6–8.9 years) there were 65 deaths, 5 year survival rate was 73.8 (95% CI 67–79%). Baseline ejection fraction, end-diastolic and end-systolic volumes of LV did not differ between pts who died and survived at 5 year after the surgery, whereas LAS was significantly higher and GLSRe/GLSRa was significantly lower in survivors. Cox proportional hazard model adjusted to demographic and clinical variables demonstrated that LAS and GLSRe/GLSRa were independent predictors of all-cause death, with HR of 0.79 (95% CI 0.66–0.95, p=0.012) for each 5% increase of LAS and HR of 1.24 (95% CI 1.1–1.4, p=0.001) for each 0.5 increase of GLSRe/GLSRa. Moreover, GLSRe/GLSRa remained an independent predictor after additional adjustment for LV end-systolic volume, sphericity index and presence of mitral insufficiency of grade 2 and higher. A significant difference in median survival time was demonstrated according to the following cut-offs: LAS ≥16.7% (12.1 vs. 6.4 years, p=0.01), GLSRe/GLSRa ratio ≥2.3 (3.3 years vs. 10.2 years, p=0.0005) (Figure). The classification and regression tree analysis with the application of all two-dimensional, Doppler and various speckle-tracking echocardiographic parameters revealed that GLSRe/GLSRa and LAS were the most important echocardiographic variables for risk stratification for 5-year mortality.

Conclusion

This study demonstrates that STE parameters of LV diastolic function are important predictors of all-cause mortality after surgical ventricular repair due to anteroapical aneurysm of LV and could be used in the preoperative decision-making process.

Funding Acknowledgement

Type of funding source: None

Validity of visual assessment of aortic valve morphology in patients with aortic stenosis using two-dimensional echocardiography

The diagnostic value of a visual assessment of aortic valve (AV) morphology for grading aortic stenosis (AS) remains unclear. A visual score (VS) for assessing the AV was developed and its reliability with respect to Doppler measurements and the calcium score (ctCS) derived by multislice computed tomography was evaluated. 99 Patients with AS of various severity and 38 patients without AS were included in the analysis. Echocardiographic studies were evaluated using the new VS which includes echogenicity, thickening, localization of lesions and leaflet mobility, with a total score ranging from 0 to 11. The association of VS with ctCS and the severity of AS was analyzed. There was a significant correlation of VS with AV hemodynamic parameters and with ctCS. The cut-off value for the detection of AS of any grade was a VS of 6 (sensitivity 95%, specificity 85% for women; sensitivity 85%, specificity 88% for men). A VS of 9 for women and of 10 for men was able to predict severe AS with a high specificity (96% in women and 94% in men, AUC 0.8 and 0.86, respectively). The same cut-off values were identified for the detection of ctCS of ≥ 1600 AU and ≥ 3000 AU with a specificity of 77% and 82% (AUC 0.69 and 0.81, respectively). Assessment of aortic valve morphology can serve as an additional diagnostic tool for the detection of AS and an estimation of its severity.

Transcatheter Restoration of the Left Ventricular Outlet in a Patient With an Implanted Apicoaortic Conduit

We describe the transcatheter management of severe aortic regurgitation in a middle-aged patient with a porcelain aorta who underwent implantation of an apicoaortic valved conduit 12 years ago. Instantaneous relief of heart failure symptoms was achieved by restoring antegrade blood flow to the ascending aorta. (Level of Difficulty: Advanced.)

Endovascular treatment of an anastomotic outflow graft pseudoaneurysm of the descending aorta after implantation of a left ventricular assist device

INTRODUCTION

Outflow graft (OG) obstruction is a dangerous complication that may occur for various reasons after the implantation of the left ventricular assist device (LVAD).

CASE REPORT

In this study, we describe the case of a 67-year-old patient on LVAD support who developed a late pseudoaneurysm of the OG anastomosis (to the descending aorta) causing OG stenosis at the level of the anastomosis. The patient was treated with a customized fenestrated endovascular stent graft placed into the descending aorta and stent implantation into the OG.

Surgical treatment of outflow graft kinking complicated by external obstruction with a fibrin mass in a patient with LVAD

BACKGROUND

Outflow graft (OG) obstruction is a dangerous complication that may occur for various reasons after left ventricular assist device (LVAD) implantation.

CASE SUMMARY

We describe the case of a 51-year-old patient on LVAD support who developed significant OG kinking and external OG obstruction due to a fibrin mass causing severe stenosis. Both the OG kinking and external obstruction were eliminated via a left lateral thoracotomy.

Reliability and Influence on Decision Making of fully-automated vs. semi-automated Software Packages for Procedural Planning in TAVI

Precise procedural planning is crucial to achieve excellent results in patients undergoing Transcatheter aortic valve implantation (TAVI). The aim of this study was to compare the semi-automated 3mensio (3 m) software to the fully-automated HeartNavigator3 (HN) software. We randomly selected 100 patients from our in-house TAVI-registry and compared aortic annulus and perimeter as well as coronary distances between 3m-measurements and post-hoc HN-measurements. Finally, we retrospectively simulated prosthesis choice based on HN-measurements and analyzed the differences compared to routinely used 3 m based strategy. We observed significant differences between the two software packages regarding area (3 m 464 ± 88 mm², HN 482 ± 96 mm², p < 0.001), perimeter (3 m 77 ± 7 mm, HN 79 ± 8 mm, p < 0.001) and coronary distances (LCA: 3 m 13 ± 3 mm, HN 12 ± 3 mm, p < 0.001; RCA: 3 m 16 ± 3 mm, HN 15 ± 3 mm, p < 0.001). Prosthesis choice simulation based on newly obtained HN-measurements would have led to a decision change in 18% of patients, with a further reduction to 4% following manual adjustment of HN-measurements. The fully-automatic HN-software provides higher values for annular metrics and lower annulus-to-coronary-ostia distances compared to 3m-software. Measurement differences did not influence clinical outcome. Both, the HN-software and the 3m-software are sophisticated, reliable and easy to use for the clinician. Manual adjustment of HN-measurements may increase precision in complex aortic annulus anatomy.

1036 Prognostic role of left ventricle longitudinal strain for the prediction of survival after surgical ventricular repair

Background

Surgical ventricular repair (SVR) in patients with ischemic cardiomyopathy is aimed to reshape left ventricle (LV) and reduce its volume in order to improve prognosis and quality of life. There are controversies regarding benefit of SVR, especially in patients with severely enlarged LV.

Purpose

Our purpose was to investigate prognostic value of LV longitudinal strain for survival and for the improvement of LV function after SVR in patients with anteroapical LV aneurysm.

Methods

218 pts (2005-2018, mean age 63.6 ± 11.2y, 73.9% males) with anteroapical LV aneurysm due to myocardial infarction underwent SVR combined with coronary bypass grafting (77.5%), mitral valve repair (18.3%) and LV thrombectomy (22.0%). Preoperative strain analysis was done retrospectively for 146 patients. Prognostic value of strain was tested in pts according to the LV end systolic volume index (LVESVI) with the cut-off value of 60ml/m². In 17 pts 1-year follow-up with strain quantification was done.

Results

During a median follow-up of 3.9 years (IQR: 1.0-6.8 years) there were 68 deaths and 1 patient was lost to follow-up. 30-days survival rate was 93.5% (95%CI: 90.3; 96.9%), 5 year survival – 72.5% (95%CI: 66.0-79.6%). Pts who died were significantly older, with higher proportion of diabetes (DM), peripheral artery disease, renal failure (RF) and atrial fibrillation (AF). Baseline ejection fraction (EF) and global longitudinal strain (GLS) did not differ significantly. Whereas basal longitudinal strain (BLS) was higher (more negative) in pts who survived (-11.4 ± 3% vs. -10.1 ± 4%, p = 0.027). Risk stratification by tertiles revealed that BLS was a significant predictor of survival. The risk of dying was 3 times higher for pts in the lowest tertile compared to those in the highest tertile (HR: 2.94, 95%CI:1.37-6.25, p = 0.013). When adjusted to age, AF, DM, RF, and previous heart surgery, BLS was an independent predictor of death (HR = 1.14, 95%CI:1.03;1.26, p = 0.032). At 1-year follow-up (12.7 ± 5.1 months) there was significant decrease of LV end-diastolic and end-systolic volume indices, from 102.8 ± 24.1 ml/m² to 77.9 ± 24 ml/m² (p &lt; 0.001) and from 67 ± 23.2 ml/m² to 44.3 ± 7.6 ml/m² (p &lt; 0.001), correspondingly, and increase of EF from 36.3 ± 9.4% to 44.4 ± 7.6% (p = 0.001). The mean systolic GLS improved from -6.6 ± 2.6% to -8.7 ± 3.2%, p = 0.008. Among 81 segments with baseline hypokinesia, 44 segments (54.3%) recovered their contractility, 36 segments (44.4%) remained hypokinetic and 1 segment deteriorated to akinesia. Mean systolic strain of segments which showed recovery was -6.6 ± 4.0% compared to -3.8 ± 4.5% with no improvement (p = 0.005). Cut-off value of systolic strain for prediction of recovery was -5.4 % (AUC = 0.69, p = 0.004; PPV = 0.73, NPV = 0.61).

Conclusion

Our study demonstrates that BLS is an independent predictor of survival after SVR in patients with LV anteroapical aneurysm. Furthermore, higher systolic strain predicts recovery of LV regional function at 1-year after SVR.

P819 Outflow graft twist occlusion in the heartmate 3 left ventricular assist system in 7 cases: analysis of potential mechanisms using computed tomography

Background

Twist of the outflow graft (OG) of the HeartMate 3 left ventricular (LV) assist device (HM3) with subsequent occlusion is a rare, but life-threatening complication.

Purpose

We evaluated if potential implantation technique dependent mechanisms of OG twist can be predicted by multislice computed tomography (MSCT).

Methods

We retrospectively analyzed clinical, echocardiographic and MSCT data of 7 patients with angiographically proven and surgically corrected OG twist and of 11 consecutive patients without any type of pump obstruction. MSCT parameters were: position of inflow cannula related to anatomical LV apex (1), angulation of axis of inflow cannula related to LV axis (2), orientation of outflow channel of the pump housing related to LV axis (3), OG course (4). Echocardiographic parameters were LV end-diastolic diameter (LVEDD) and aortic valve opening.

Results

Mean time from implantation to twist was 563 ± 161 days. Preoperative LVEDD (64.6 ± 9.8 mm vs. 67.4 ± 10.2 mm, p = 0.563) was similar. LVEDD reduction after implantation (20% vs. 28%) and prevalence of aortic valve opening was higher in the twist group (71% vs. 45%). The MSCT measurements showed a high degree of heterogeneity in both groups: (1) differed from superior to infero-lateral; (2) varied from cranial to caudal, lateral and medial; (3) varied from antero-septal to inferior. (4) showed an incidence of non-obstructive kinking of 29% and 36%, respectively.

Conclusion

Marked heterogeneity of the measured MSCT parameters was observed in both groups. No specific pattern or geometric relation could be attributed to the OG twist phenomenon.

Assessment of Global Longitudinal and Circumferential Strain Using Computed Tomography Feature Tracking: Intra-Individual Comparison with CMR Feature Tracking and Myocardial Tagging in Patients with Severe Aortic Stenosis

In this study, we used a single commercially available software solution to assess global longitudinal (GLS) and global circumferential strain (GCS) using cardiac computed tomography (CT) and cardiac magnetic resonance (CMR) feature tracking (FT). We compared agreement and reproducibility between these two methods and the reference standard, CMR tagging (TAG). Twenty-seven patients with severe aortic stenosis underwent CMR and cardiac CT examinations. FT analysis was performed using Medis suite version 3.0 (Leiden, The Netherlands) software. Segment (Medviso) software was used for GCS assessment from tagged images. There was a trend towards the underestimation of GLS by CT-FT when compared to CMR-FT (19.4 ± 5.04 vs. 22.40 ± 5.69, respectively; p = 0.065). GCS values between TAG, CT-FT, and CMR-FT were similar (p = 0.233). CMR-FT and CT-FT correlated closely for GLS (r = 0.686, p < 0.001) and GCS (r = 0.707, p < 0.001), while both of these methods correlated moderately with TAG for GCS (r = 0.479, p < 0.001 for CMR-FT vs. TAG; r = 0.548 for CT-FT vs. TAG). Intraobserver and interobserver agreement was excellent in all techniques. Our findings show that, in elderly patients with severe aortic stenosis (AS), the FT algorithm performs equally well in CMR and cardiac CT datasets for the assessment of GLS and GCS, both in terms of reproducibility and agreement with the gold standard, TAG.

Ultrasonic sensor concept to fit a ventricular assist device cannula evaluated using geometrically accurate heart phantoms

Future left ventricular assist devices (LVADs) are expected to respond to the physiologic need of patients; however, they still lack reliable pressure or volume sensors for feedback control. In the clinic, echocardiography systems are routinely used to measure left ventricular (LV) volume. Until now, echocardiography in this form was never integrated in LVADs due to its computational complexity. The aim of this study was to demonstrate the applicability of a simplified ultrasonic sensor to fit an LVAD cannula and to show the achievable accuracy in vitro. Our approach requires only two ultrasonic transducers because we estimated the LV volume with the LV end-diastolic diameter commonly used in clinical assessments. In order to optimize the accuracy, we assessed the optimal design parameters considering over 50 orientations of the two ultrasonic transducers. A test bench was equipped with five talcum-infused silicone heart phantoms, in which the intra-ventricular surface replicated papillary muscles and trabeculae carnae. The end-diastolic LV filling volumes of the five heart phantoms ranged from 180 to 480 mL. This reference volume was altered by ±40 mL with a syringe pump. Based on the calibrated measurements acquired by the two ultrasonic transducers, the LV volume was estimated well. However, the accuracies obtained are strongly dependent on the choice of the design parameters. Orientations toward the septum perform better, as they interfere less with the papillary muscles. The optimized design is valid for all hearts. Considering this, the Bland-Altman analysis reports the LV volume accuracy as a bias of ±10% and limits of agreement of 0%-40% in all but the smallest heart. The simplicity of traditional echocardiography systems was reduced by two orders of magnitude in technical complexity, while achieving a comparable accuracy to 2D echocardiography requiring a calibration of absolute volume only. Hence, our approach exploits the established benefits of echocardiography and makes them applicable as an LV volume sensor for LVADs.

Multislice computed tomography-guided surgical repair of acquired posterior left ventricular aneurysms: demonstration of mitral valve and left ventricular reverse remodelling

OBJECTIVES

Involvement of the mitral valve (MV) apparatus represents a challenge in surgical ventricular repair (SVR) of posterior left ventricular (LV) aneurysms. This study sought to investigate whether multislice computed tomography (MSCT) assessment can be used to optimize the surgical procedure for posterior LV aneurysms.

METHODS

Thirty patients (m : w = 24 : 6, age 38-78, median 66 years; mean New York Heart Association class 2.98) with posterior LV aneurysm were operated upon. MSCT was performed in 24 patients before and after surgery. End-diastolic and end-systolic volumes of LV and aneurysm were indexed to body surface area (LVEDVI/LVESVI, AEDVI/AESVI). The MV apparatus was characterized by coaptation distance (CD), tenting area (TA), MV closure angle (MVCA), MV annulus area (MVAA) and interpapillary muscle distance (IMD).

RESULTS

Thirty-day mortality was 10% and 5-year survival rate was 83%. After surgery, LVEDVI decreased from 151.2 ± 84.1 to 85.7 ± 28.3 ml/m(2) (P = 0.001) and LVESVI from 110.6 ± 88.8 to 50.2 ± 22.9 ml/m(2) (P = 0.001). LV ejection fraction increased from 31.5 ± 15.1 to 43.4 ± 9.9% (P = 0.001). Preoperative MSCT showed significantly higher values of MVAA, CD and TA in patients who needed MV repair or replacement. Postoperative reduction of mitral regurgitation in patients without MV surgery corresponded with significant reduction in intercommissural diameter, anteroposterior diameter, MVAA, TA, CD, MVCA and IMD.

CONCLUSIONS

MSCT represents an excellent diagnostic tool for the assessment of MV and LV geometry. MSCT-guided SVR of submitral LV aneurysms leads to excellent mid-term results. On the basis of the MSCT assessment, we propose an algorithm for surgical planning in posterior LV aneurysms.

Posterior annulus shortening increases leaflet coaptation in ischemic mitral incompetence: a new and valid technique

BACKGROUND

We introduce a technique of posterior annulus shortening to augment leaflet coaptation which addresses the restrictive mitral leaflet mobility in ischemic mitral incompetence (IMI), and report its long-term outcome.

METHODS

Between 1992 and 2012, 75 patients (mean age, 64.6±10.4 years; median, 66.0 years; range, 35.0-86.1 years) underwent repair of IMI by posterior annulus shortening to augment leaflet coaptation surface area. This technique reduces the annular diameter to between 23 and 25 mm and decreases the valve orifice to between 3.5 to 4.5 cm(2), which is sufficient to ensure an adequate leaflet coaptation area. An untreated pericardial strip is used to reinforce the shortened annulus in order to avoid redilatation. This augments the posterior leaflet by increasing the ratio of leaflet area/valve orifice where the coaptation gap is the greatest. The tissue strip increases and heightens the area which the posterior leaflet offers to the anterior leaflet for coaptation during closure, making valve closure possible in advanced leaflet restriction.

RESULTS

During a mean follow-up of 7.62±0.66 (median 8.53, range, 3.6-20.9) years, New York Heart Association (NYHA) functional class significantly improved, left ventricular ejection fraction (LVEF) increased and there was a tremendous abatement of MI (P<0.01). Annular area was reduced from 9.2 to 5.8 cm(2). Coaptation area was increased from a complete lack thereof to 6.6 mm(2) post-repair. CT showed posterior annulus size reduction from 70.4 to 54 mm and an increase in posterior leaflet length from 15.9 to 19.6 mm. A remarkable CT finding was the increase in coaptation length from 5.2 to 8.2 mm. Eighteen-year freedom from moderate MI, freedom from reoperation and survival rates were 80.7%±9%, 84.9%±4.2% and 65.1%±6.3%, respectively.

CONCLUSIONS

Posterior annulus shortening with pericardial strip augmentation addressing the lack of leaflet coaptation is a simple, reproducible and highly effective technique to restore valve competence in IMI.

Giant pseudoaneurysm on left ventricular posterolateral wall with an orifice between papillary muscles

A left ventricular pseudoaneurysm develops when myocardial rupture is contained by the pericardium. Although left ventricular pseudoaneurysm has been a topic of discussion since the pioneering days of open heart surgery, it still remains a technical challenge in reconstructive cardiac surgery. Reoperation following pseudoaneurysm repair is also frequent. We report surgical treatment in two patients with a pseudoaneurysm on the left ventricular posterolateral wall. The pseudoaneurysm and left ventricular cavity communicated at a point just between the anterolateral and posteromedial papillary muscle attachments. Such a manifestation is highly infrequent but potentially lethal. During aneurysmectomy, special attention was paid to avoid the development of mitral regurgitation because the papillary muscle geometry changes after removal of the pseudoaneurysm. In both cases, surgical decision-making was facilitated by preoperative assessment using electrocardiographic-gated multislice computed tomography.