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.

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 >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 >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

VAD related infections and the risk of pump thrombosis and thromboembolic events: a EUROMACS study

Background

In patients supported by a ventricular assist device (VAD) major infections are a frequently reported adverse event with increased morbidity and mortality.

Purpose

The purpose of this study was to investigate the possible association between infections and cerebrovascular accidents (CVAs) in VAD patients.

Methods

An analysis of the European Registry for Patients Assisted with Mechanical Circulatory Support (EUROMACS) was performed identifying all patients aged ≥18 years with a LVAD or BiVAD implantation. Infections were categorized as VAD-specific infections, VAD-related infections and, non-VAD infections. An extended Kaplan-Meier analysis for the risk of CVA and mortality with infection as a time-dependent covariate was performed. Furthermore, a multivariable Cox proportional hazard model was performed including 24 variables.

Results

For this analysis 3784 patients were included, with 45 patients being supported by a BiVAD and 3739 by an LVAD. The majority of patients were male (83.2%) and 60.5% had an INTERMACS patient profile 2 or 3. During follow-up, 3108 major infections were identified in 1385 (36.6%) of the patients, while 673 CVAs were identified in 545 (14.4%) of the patients. Extended Kaplan-Meier analysis with first infection as time-dependent covariate revealed a hazard ratio (HR) for CVA of 1.95 (95% CI: 1.57–2.36; p<0.005) (Figure) and 1.50 (95% CI: 1.33–1.68, p<0.005) for mortality. Multivariable analysis confirmed a significant association for infection and CVAs with a HR of 1.46 (95% CI: 1.29–1.64). With infections subcategorized, VAD-specific (HR: 1.57 (95% CI: 1.18–2.09)) and VAD-related infections (HR: 2.04 (95% CI: 1.44–2.89)) remained significantly associated with CVA but non-VAD infections (HR: 1.22 (95% CI: 0.92–1.64)) were not.

Conclusion

Both VAD-related and VAD-specific infections are associated with a significantly increased risk of CVA with increased risk of mortality.

Funding Acknowledgement

Type of funding sources: None. KM freedom of CVA and infection

Mechanical unloading by miniature axial flow pumps in late cardiac allograft failure due to acute rejection

Allograft failure secondary to rejection commonly requires a multimodal treatment, ultimately including mechanical circulatory support. A few case reports have demonstrated the use of Impella-devices due to its assumed favorable safety profile in this fragile cohort. However, this treatment option does not play a role in choice of anti-rejective therapy in clinical routine up to date. We summarize our institutional experiences and literature mini-review on Impella-based treatment strategies in allograft rejection after heart transplantation. In all seven cases, three from our institution and four reported in the literature, Impella-based therapies led to hemodynamic stabilization in allograft failure secondary to rejection. Adverse events included hemolysis, non-fatal bleeding and in one patient a relevant aortic valve insufficiency occurred. All patients showed an improvement of allograft function. Two patients died in context of severe immunosuppression or late secondary organ failure. Based on the limited available data, we propose that Impella-mediated mechanical unloading represents a valuable option for hemodynamic stabilization in severe allograft failure due to rejection, enabling an initiation of causal therapy and thereby potentially representing an opportunity to prevent mortality. Furthermore, we hypothesize it might add to the traditional therapeutic approaches by facilitating recovery by decompressing the myocardium in allograft rejection.

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 < 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 < 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 <0.0001 <0.0001 0.215 Abstract Figure. Bland-Altman plots for LVEDV and LVESV

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

Efficacy of quadruple treatment on different types of pre-operative anaemia: secondary analysis of a randomised controlled trial

In patients with pre-operative anaemia undergoing cardiac surgery, combination treatment with intravenous iron, subcutaneous erythropoietin alpha, vitamin B12 and oral folic acid reduces allogeneic blood product transfusions. It is unclear if certain types of anaemia particularly benefit from this treatment. We performed a post-hoc analysis of anaemic patients from a randomised trial on the 'Effect of ultra-short-term treatment of patients with iron deficiency or anaemia undergoing cardiac surgery'. We used linear regression analyses to examine the efficacy of a combination anaemia treatment compared with placebo on the following deficiencies, each representing a part of the combination treatment: ferritin and transferrin saturation; endogenous erythropoietin; holotranscobalamine; and folic acid in erythrocytes. Efficacy was defined as change in reticulocyte count from baseline to the first, third and fifth postoperative days and represented erythropoietic activity in the immediate peri-operative recovery phase. In all 253 anaemic patients, iron deficiency was the most common cause of anaemia. Treatment significantly increased reticulocyte count in all regression analyses on postoperative days 1, 3 and 5 (all p < 0.001). Baseline ferritin and endogenous erythropoietin were negatively associated with change in reticulocyte count on postoperative day 5, with an unstandardised regression coefficient B of -0.08 (95%CI -0.14 to -0.02) and -0.14 (95%CI -0.23 to -0.06), respectively. Quadruple anaemia treatment was effective regardless of the cause of anaemia and its effect manifested early in the peri-operative recovery phase. The more pronounced a deficiency was, the stronger the subsequent boost to erythropoiesis may have been.

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.

P2626Outcome of patients in cardiogenic shock supported with a micro-axial blood pump providing 5 l/min blood flow

Introduction

Percutaneous mechanical circulatory support devices are increasingly used in acute cardiogenic shock (CS), despite limited evidence for their effectiveness. The aim of this study was to evaluate outcomes associated with use of the full support Impella 5 and 5.5 as a short- term left ventricular device (LVAD) and to identify preoperative predictors of short -term mortality.

Methods

Data of patients in CS (n=51) treated with the Impella 5 (n=48) and 5.5 (n=3) devices at our institution were collected retrospectively. The primary endpoint was 30-day all-cause mortality. Clinical follow up including adverse events was analyzed.

Results

Mean age was 58.2±12.1 years; 80.4% were male. 13 patients had BMI >30 kg/m2. CS was caused by acute myocardial infarction (n=14), decompensated chronic heart failure (n=29), postcardiotomy syndrom and acute myocarditis (n=4 each). Before implantation, median Intermacs profile was 1 (range 1–3) and 31 patients (61%) were on respiratory support. In 49 patients the axillary artery was used for vascular access (n=4 left and n=45 right) employing a 10mm dacron graft tunneled through the skin, in one patient left femoral artery and ascending aorta, respectively. Median support time was 14 days.

In 12 cases the pump was removed for myocardial recovery. In 15 patients a continuous flow permanent LVAD was implanted. Bleeding (n=9), thromboembolic event (n=5), pump dislodgement (n=7) requiring revision occurred during support. Seven patients developed ventricular arrhythmia requiring flow reduction. In 5 cases the pump was explanted for hemolysis, in 2 other patients pump exchange was performed. The overall 30-day survival was 53% (95% CI: 38.8–67.1%). Penalized multivariable logistic regression analysis identified preoperative elevated lactate (p=0.027) and CK-MB (p=0.022) as predictors for 30- day mortality. On the basis of these data, a nomogram to estimate 30d-mortality after Impella implantation was created.

Conclusion

Stabilization of patients suffering from CS employing temporary full support Impella LVAD is feasible and results in acceptable survival. Preoperative degree of shock and myocardial damage predict the short-term mortality. Effect of full support Impella LVAD in earlier stages of shock may prevent irreversible end organ damage.