Detection of transthyretin amyloid cardiomyopathy by automated data extraction from electronic health records

AIMS

Transthyretin amyloid cardiomyopathy (ATTR-CM), a progressive and fatal cardiomyopathy, is frequently misdiagnosed or entails diagnostic delays, hindering patients from timely treatment. This study aimed to generate a systematic framework based on data from electronic health records (EHRs) to assess patients with ATTR-CM in a real-world population of heart failure (HF) patients. Predictive factors or combinations of predictive factors related to ATTR-CM in a European population were also assessed.

METHODS AND RESULTS

Retrospective unstructured and semi-structured data from EHRs of patients from OLV Hospital Aalst, Belgium (2012-20), were processed using natural language processing (NLP) to generate an Observational Medical Outcomes Partnership Common Data Model database. NLP model performance was assessed on a random subset of EHRs by comparing algorithm outputs to a physician-generated standard (using precision, recall, and their harmonic mean, or F1-score). Of the 3127 HF patients, 103 potentially had ATTR-CM (age 78 ± 9 years; male 55%; ejection fraction of 48% ± 16). The mean diagnostic delay between HF and ATTR-CM diagnosis was 1.8 years. Besides HF and cardiomyopathy-related phenotypes, the strongest cardiac predictor was atrial fibrillation (AF; 72% in ATTR-CM vs. 60% in non-ATTR-CM, P = 0.02), whereas the strongest non-cardiac predictor was carpal tunnel syndrome (21% in ATTR-CM vs. 3% in non-ATTR-CM, P < 0.001). The strongest combination predictor was AF, joint disorders, and HF with preserved ejection fraction (29% in ATTR-CM vs. 18% in non-ATTR-CM: odds ratio = 2.03, 95% confidence interval = 1.28-3.22).

CONCLUSIONS

Not only well-known variables associated with ATTR-CM but also unique combinations of cardiac and non-cardiac phenotypes are able to predict ATTR-CM in a real-world HF population, aiding in early identification of ATTR-CM patients.

Doxorubicin-induced cardiovascular toxicity: a longitudinal evaluation of functional and molecular markers

AIMS

Apart from cardiotoxicity, the chemotherapeutic doxorubicin (DOX) induces vascular toxicity, represented by arterial stiffness and endothelial dysfunction. Both parameters are of interest for cardiovascular risk stratification as they are independent predictors of future cardiovascular events in the general population. However, the time course of DOX-induced cardiovascular toxicity remains unclear. Moreover, current biomarkers for cardiovascular toxicity prove insufficient. Here, we longitudinally evaluated functional and molecular markers of DOX-induced cardiovascular toxicity in a murine model. Molecular markers were further validated in patient plasma.

METHODS AND RESULTS

DOX (4 mg/kg) or saline (vehicle) was administered intra-peritoneally to young, male mice weekly for 6 weeks. In vivo cardiovascular function and ex vivo arterial stiffness and vascular reactivity were evaluated at baseline, during DOX therapy (Weeks 2 and 4) and after therapy cessation (Weeks 6, 9, and 15). Left ventricular ejection fraction (LVEF) declined from Week 4 in the DOX group. DOX increased arterial stiffness in vivo and ex vivo at Week 2, which reverted thereafter. Importantly, DOX-induced arterial stiffness preceded reduced LVEF. Further, DOX impaired endothelium-dependent vasodilation at Weeks 2 and 6, which recovered at Weeks 9 and 15. Conversely, contraction with phenylephrine was consistently higher in the DOX-treated group. Furthermore, proteomic analysis on aortic tissue identified increased thrombospondin-1 (THBS1) and alpha-1-antichymotrypsin (SERPINA3) at Weeks 2 and 6. Up-regulated THBS1 and SERPINA3 persisted during follow-up. Finally, THBS1 and SERPINA3 were quantified in plasma of patients. Cancer survivors with anthracycline-induced cardiotoxicity (AICT; LVEF < 50%) showed elevated THBS1 and SERPINA3 levels compared with age-matched control patients (LVEF ≥ 60%).

CONCLUSIONS

DOX increased arterial stiffness and impaired endothelial function, which both preceded reduced LVEF. Vascular dysfunction restored after DOX therapy cessation, whereas cardiac dysfunction persisted. Further, we identified SERPINA3 and THBS1 as promising biomarkers of DOX-induced cardiovascular toxicity, which were confirmed in AICT patients.

Tools to differentiate between Filamin C and Titin truncating variant carriers: value of MRI

Whereas truncating variants of the giant protein Titin (TTNtv) are the main cause of familial dilated cardiomyopathy (DCM), recently Filamin C truncating variants (FLNCtv) were identified as a cause of arrhythmogenic cardiomyopathy (ACM). Our aim was to characterize and compare clinical and MRI features of TTNtv and FLNCtv in the Belgian population. In index patients referred for genetic testing of ACM/DCM, FLNCtv and TTNtv were found in 17 (3.6%) and 33 (12.3%) subjects, respectively. Further family cascade screening yielded 24 and 19 additional truncating variant carriers in FLNC and TTN, respectively. The main phenotype was ACM in FLNCtv carriers whereas TTNtv carriers showed either an ACM or DCM phenotype. Non-sustained Ventricular Tachycardia was frequent in both populations. MRI data, available in 28/40 FLNCtv and 32/52 TTNtv patients, showed lower Left Ventricular (LV) ejection fraction and lower LV strain in TTNtv patients (p < 0.01). Conversely, both the frequency (68% vs 22%) and extent of non-ischemic myocardial late gadolinium enhancement (LGE) was significantly higher in FLNCtv patients (p < 0.01). Hereby, ring-like LGE was found in 16/19 (84%) FLNCtv versus 1/7 (14%) of TTNtv patients (p < 0.01). In conclusion, a large number of FLNCtv and TTNtv patients present with an ACM phenotype but can be separated by cardiac MRI. Whereas FLNCtv patients often have extensive myocardial fibrosis, typically following a ring-like pattern, LV dysfunction without or limited replacement fibrosis is the common TTNtv phenotype.

Association of Mild-to-Moderate Aortic Regurgitation With Outcomes in Heart Failure With Preserved Ejection Fraction

OBJECTIVE

To assess aortic regurgitation (AR) prevalence, its hemodynamic effect, and long-term prognostic implications in patients admitted with de novo or worsened heart failure with preserved ejection fraction (HFpEF).

METHODS

Consecutive patients hospitalized with de novo or worsened HFpEF between 2014 and 2020 were enrolled. Patients with more than moderate aortic and/or mitral valve disease were excluded. Based on the presence and degree of AR, patients were divided into those without AR, those with mild, and those with moderate AR. Data on cardiovascular death, heart failure (HF) rehospitalization, and their composite (major adverse cardiovascular events) were collected.

RESULTS

The final study population consisted of 458 HFpEF patients: 156 (34.1%) with mild-AR, 153 (33.4%) with moderate-AR, and the remaining 149 (32.5%) with no AR. Mild-to-moderate AR patients were older, with larger left atrium-left ventricle (LV) volumes, greater LV mass index, higher filling pressure, and prevalence of diastolic dysfunction compared with the no-AR group (all P<.05). During 5-year follow-up, 113 patients died of cardiovascular causes, 124 patients were rehospitalized for HF, whereas 196 experienced the composite endpoint. Mild-to-moderate AR was identified as an independent predictor of all-cause death (HR, 1.62; 95% CI, 1.14 to 1.58; P=.04) and major adverse cardiovascular event occurrence (HR, 1.48; 95% CI, 1.05 to 2.09; P=.02). A total of 126 (35.5%) of 355 patients showed progression of AR at follow-up echocardiography.

CONCLUSION

Mild-to-moderate AR is common among patients hospitalized for HFpEF. It is associated with adverse LV remodeling and worse long-term outcomes. These findings warrant further prospective studies addressing the importance of AR in prognostic stratification and exploring therapeutic strategies to mitigate its hemodynamic effect on HF.

Cardio-renal-metabolic syndrome: clinical features and dapagliflozin eligibility in a real-world heart failure cohort

AIMS

The Cardiovascular Outcomes Retrospective Data analysIS in Heart Failure (CORDIS-HF) is a single-centre retrospective study aimed to (i) clinically characterize a real-world population with heart failure (HF) with reduced (HFrEF) and mildly reduced ejection fraction (HFmrEF), (ii) evaluate impact of renal-metabolic comorbidities on all-cause mortality and HF readmissions, and (iii) determine patients' eligibility for sodium-glucose cotransporter 2 inhibitors (SGLT2is).

METHODS AND RESULTS

Using a natural language processing algorithm, clinical data of patients diagnosed with HFrEF or HFmrEF were retrospectively collected from 2014 to 2018. Mortality and HF readmission events were collected during subsequent 1 and 2 year follow-up periods. The predictive role of patients' baseline characteristics for outcomes of interest was assessed using univariate and multivariate Cox proportional hazard models. Kaplan-Meier analysis was used to determine if type 2 diabetes (T2D) and chronic kidney disease (CKD) impacted mortality and HF readmission rates. The European SGLT2i label criteria were used to assess patients' eligibility. The CORDIS-HF included 1333 HF patients with left ventricular ejection fraction (LVEF) < 50% (413 HFmrEF and 920 HFrEF), who were predominantly male (69%) with a mean [standard deviation (SD)] age of 74.7 (12.3) years. About one-half (57%) of patients presented CKD and 37% T2D. The use of guideline-directed medical therapy (GDMT) was high (76-90%). HFrEF patients presented lower age [mean (SD): 73.8 (12.4) vs. 76.7 (11.6) years, P < 0.05], higher incidence of coronary artery disease (67% vs. 59%, P < 0.05), lower systolic blood pressure [mean (SD): 123 (22.6) vs. 133 (24.0) mmHg, P < 0.05], higher N-terminal pro-hormone brain natriuretic peptide (2720 vs. 1920 pg/mL, P < 0.05), and lower estimated glomerular filtration rate [mean (SD): 51.4 (23.3) vs. 54.1 (22.3) mL/min/1.73 m² , P < 0.05] than those with HFmrEF. No differences in T2D and CKD were detected. Despite optimal treatment, event rates for the composite endpoint of HF readmission and mortality were 13.7 and 8.4/100 patient years. The presence of T2D and CKD negatively impacted all-cause mortality [T2D: hazard ratio (HR) = 1.49, P < 0.01; CKD: HR = 2.05, P < 0.001] and hospital readmission events in all patients with HF. Eligibility for SGLT2is dapagliflozin and empagliflozin was 86.5% (n = 1153) and 97.9% (n = 1305) of the study population, respectively.

CONCLUSIONS

This study identified high residual risk for all-cause mortality and hospital readmission in real-world HF patients with LVEF < 50% despite GDMT. T2D and CKD aggravated the risk for these endpoints, indicating the intertwinement of HF with CKD and T2D. SGLT2i treatment that clinically benefits these different disease conditions can be an important driver to lower mortality and hospitalizations in this HF population.

Myocardial work analysis for early detection of type 1 CTRCD and patient risk stratification

Aim

This prospective longitudinal study analyses the potential role of Myocardial Work in early detection of cardiotoxicity during chemotherapy and its added value for prognosis and patients' risk stratification.

Methods

We enrolled 47 consecutive female patients with HER2-positive breast cancer referred for anti-cancer therapy based on anthracycline and taxane. Patients with depressed LV function at baseline were excluded. Medical therapy, clinical parameters and echocardiographic data were recorded at baseline and at 3, 6, 12 months follow-up. Additionally, cuff blood pressure was measured at the time of 2D-TTE examination and adequate echocardiographic images were stored for off-line analysis.

Results

CTRCD was detected in 17 patients (36%) while 30 patients remained free of CTRCD (64%). There were no intergroup differences for age, body mass index, resting heart rate and brachial arterial pressure. Both groups presented unaltered LV systolic function after 3 months follow-up yet overt cardiac dysfunction showed up in the CTRCD group at 6 months with significant decline in LVEF, GLS, MWI, MWE and CW from baseline values (LVEF, %: 56.0±4.1 vs 52.2±6.5; GLS, %: −20.9±1.9 vs −17.6±3.2; MWI, mmHg%: 2125±348 vs 1704±620; MWE, %: 95±2.6 vs 93±3.9 and CW, mmHg%: 2562±3567 vs 2212±455, p&lt;0.05). Additionally, GLS, MWI and MWE at 6 months were significantly worse in the CTRCD group vs non-CTRCD group (GLS, %: −17.6±3.2 vs −20.6±1.8; MWI, mmHg%: 1704±620 vs 2087±347; MWE, %: 93±3.9 vs 96±1.5, p&lt;0.05). Depressed LV systolic function persisted after 1 year follow-up (Figure 1). After 3 months, only de relative change in GLS and WW from baseline were significantly worse in CTRCD vs non-CTRCD (ΔGLS: +3.7±11 vs −3.9±10, ΔWW: +46.1±83 vs +2.2±45). Whereas no correlation was found, the combination of both ΔGLS and ΔWW at 3 months showed stronger prognostic value for CTRCD than each parameter alone, AUC of 0.72 (Figure 2).

Conclusion

These findings point the superiority of Myocardial Work for early type 1 CTRCD detection in comparison to the current diagnostic tools. Additionally, we suggest the add-on value of ΔWW on top of ΔGLS quantification for better patient risk stratification. These are promising results for better clinical surveillance of cardiac function during cancer treatment.

Funding Acknowledgement

Type of funding sources: None.

Saline-induced coronary hyperemia with continuous intracoronary thermodilution is mediated by intravascular hemolysis

Objectives

To test whether local hemolysis is a potential mechanism of saline-induced coronary hyperemia.

Background

Absolute coronary flow can be measured by intracoronary continuous thermodilution of saline through the lateral side holes of a dedicated infusion cathete. A saline infusion rate at 15–20 mL/min induces an immediate, steady-state, maximal microvascular vasodilation. The mechanism of this hyperemic response remains unclear.

Methods

Twelve patients undergoing left and right catheterization were included. The left coronary artery and the coronary sinus were selectively cannulated. Absolute resting and hyperemic coronary flow were measured by continuous intracoronary thermodilution. Arterial and venous samples were collected from the coronary artery and the coronary sinus in five phases: baseline (BL); resting flow measurement (Rest, saline infusion at 10 mL/min); hyperemia (Hyperemia,saline infusion at 20 mL/min); post-hyperemia (Post-Hyperemia, two minutes after the cessation of saline infusion); and control phase (Control, during infusion of saline through the guide catheter at 30 mL/min).

Results

Hemolysis was visually detected only in the centrifugated venous blood samples collected during the Hyperemia phase. As compared to Rest, during Hyperemia both LDH (131.50±21.89 U/dL [Rest] and 258.33±57.40 U/dL [Hyperemia], p&lt;0.001) and plasma free hemoglobin (PFHb, 4.92±3.82 mg/dL [Rest] and 108.42±46.58 mg/dL [Hyperemia], p&lt;0.001) significantly increased in the coronary sinus. The percentage of hemolysis was significantly higher during the Hyperemia phase (0.04±0.02% [Rest] vs 0.89±0.34% [Hyperemia], p&lt;0.001).

Conclusions

Saline-induced hyperemia through a dedicated intracoronary infusion catheter is associated with hemolysis. Vasodilatory compounds released locally, like ATP, are likely ultimately responsible for localized microvascular vasodilation.

Funding Acknowledgement

Type of funding sources: None.

Global longitudinal strain and NT-proBNP as predictors for LV function recovery after TAVR

Introduction

Abnormal GLS values as well as high plasma levels of NT-proBNP previous to TAVR are independent predictors for higher peri-procedural mortality. Moreover, in a subgroup of TAVR patients LV function does not recover following the procedure. Until today, it is still unclear how to predict impaired post-procedural LV function for optimal clinical patient's management.

Purpose

This study was set up to assess the predictive value of baseline GLS and NT-proBNP levels on LV function recovery (LVfr) in a cohort of patients with severe AS referred for TAVR.

Methods

A total of 25 patients (9 male, 84±5 yo, EF 50±11%) with severe AS (AVA 0.6±0.3 cm2, MPG 49±16 mmHg) referred for TAVR were included. Blood analysis and TTE were performed before intervention (baseline, bl) and at follow-up (fu). Myocardial work was analysed offline integrating the longitudinal strain and afterload pressure (SBP + AVPmean). LVfr was defined as GLS &lt;−19% at fu. The median values at bl of NT-proBNP (1781 ng/L) and GLS (−15%) were taken as cut-off to categorize patients in 4 groups: NT-proBNPhighGLShigh, NT-proBNPlowGLShigh, NT-proBNPhighGLSlow and NT-proBNPlowGLSlow. The ROC curve analysis for prediction of LVfr after TAVR were performed.

Results

LV function recovered in 13 patients (52%). Despite similar EF and global MWI after TAVR, the LV contraction became more efficient as evidenced by a significant improvement (bl vs fu, p&lt;0.05) in GLS (−14±4.5 vs −18±4.2%), MWW (400±510 vs 157±107 mmHg%) MWE (88±6 vs 92±6%) together with a reduction in afterload pressure (203±38 vs 156±22 mmHg, p&lt;0.05). In the NT-proBNPlow groups, GLS (−15±4 vs −20±3%, p&lt;0.05) and MCW (2166±874 vs 2978±634 mmHg%, p&lt;0.05) at fu were significantly better when compared to the NT-proBNPhigh groups. Likewise, the GLSlow groups showed higher EF (47±10 vs 54±6%, p&lt;0.05) and MCW (2181±832 vs 2961±715 mmHg%, p&lt;0.05) than the GLShigh groups at fu. Interestingly, the GLSlow groups had lower LVESV (57±38 vs 29±10 ml, p&lt;0.05) and LVEDV (113±49 vs 80±20 ml, p&lt;0.05) post-TAVR than the GLShigh groups which suggests a positive remodelling following afterload reduction. At the ROC curve analysis, combined GLS and NT-proBNP at bl were better predictors for LVfr than each parameter alone, AUC 0.86 (Fig. 1). Additionally, only 20% LVfr was seen in the NT-proBNPhighGLShigh group in contrast to 67–75% in the other groups.

Conclusion

Elevated afterload in severe AS leads to a physiological reduction of GLS. Although the decrease in afterload after TAVR beneficially affects GLS and may lead to LVfr, this was not observed in a subgroup of patients with high NT-proBNP levels in whom GLS remained impaired at follow-up. We speculate that myocardial tissue damage and fibrosis due to long lasting high pressure exposure may partly be responsible for this observation. The combination of pre-procedural NT-proBNP levels and GLS shows strong predictive potential for LVfr after TAVR and larger studies are warranted for further evaluation and cut-off values determination.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Cardiovascular Research Center Aalst (npo)

T Cell and Antibody Response Following Double Dose of BNT162b2 mRNA Vaccine in SARS-CoV-2 Naïve Heart Transplant Recipients

Introduction: Preliminary studies have suggested a low post-vaccination antibody response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in heart transplant(HTx)recipients. Although many studies have focused on the role of antibodies in vaccine-induced protection against SARS-CoV-2, the role of T cell immunity is less well characterized. To date, data regarding seroconversion and T cell response after mRNA SARS-CoV-2 vaccination in patients undergoing HTx are scarce. Therefore, the present study aimed to assess the specific memory humoral and cellular responses after two doses of the BNT162b2 vaccine in HTx recipients. Methods: Blood was drawn from heart transplant (HTx) recipients at two pre-specified time points after the first and second vaccine doses to measure both the anti-SARS-CoV-2 antibody response against the spike protein and the SARS-CoV-2-reactive T cell response. Results: Our study included 34 SARS-CoV-2 naïve HTx recipients (mean age, 61 ± 11 years). The mean time from transplantation to the first vaccine dose is 10 ± 10 years. Subgroup analysis (n = 21) demonstrated that after the first vaccine dose, only 14% had antibodies and 19% had a SARS-CoV-2-reactive T-cell response, which increased to 41% and 53%, respectively, after the second dose. Interestingly, 20% of patients with no antibodies after the second dose still had a positive SARS-CoV-2-reactive T cell response. The percentage of patients with positive S-IgG antibody titers was significantly higher 5 years after transplantation (18% 0–5 years post-TX vs. 65% 5 years post-TX, p = 0.013). Similarly, 5 years after heart transplantation, the percentage of patients with a T cell response was significantly higher (35% 0–5 years post-TX vs. 71% 5 years post-TX, p = 0.030). Conclusions: In SARS-CoV-2 naïve HTx recipients, post-vaccination antibody titers but also SARS-CoV-2 specific T cell response are low. Therefore, the protection from SARS-CoV-2 that is generally attributed to vaccination should be regarded with caution in HTx recipients.

Utilizing longitudinal data in assessing all-cause mortality in patients hospitalized with heart failure

AIMS

Risk stratification in patients with a new onset or worsened heart failure (HF) is essential for clinical decision making. We have utilized a novel approach to enrich patient level prognostication using longitudinally gathered data to develop ML-based algorithms predicting all-cause 30, 90, 180, 360, and 720 day mortality.

METHODS AND RESULTS

In a cohort of 2449 HF patients hospitalized between 1 January 2011 and 31 December 2017, we utilized 422 parameters derived from 151 451 patient exams. They included clinical phenotyping, ECG, laboratory, echocardiography, catheterization data or percutaneous and surgical interventions reflecting the standard of care as captured in individual electronic records. The development of predictive models consisted of 101 iterations of repeated random subsampling splits into balanced training and validation sets. ML models yielded area under the receiver operating characteristic curve (AUC-ROC) performance ranging from 0.83 to 0.89 on the outcome-balanced validation set in predicting all-cause mortality at aforementioned time-limits. The 1 year mortality prediction model recorded an AUC of 0.85. We observed stable model performance across all HF phenotypes: HFpEF 0.83 AUC, HFmrEF 0.85 AUC, and HFrEF 0.86 AUC, respectively. Model performance improved when utilizing data from more hospital contacts compared with only data collected at baseline.

CONCLUSIONS

Our findings present a novel, patient-level, comprehensive ML-based algorithm for predicting all-cause mortality in new or worsened heart failure. Its robust performance across phenotypes throughout the longitudinal patient follow-up suggests its potential in point-of-care clinical risk stratification.

An unexpected cause of a swollen pacemaker pocket: a case report

Background

A complication originating from the pacemaker pocket after device implantation can most often be explained by a post-operative pocket haematoma, or, less frequently, by a pocket infection. Both conditions need immediate assessment, dedicated treatment, and specialized follow-up. In rare cases, however, a swollen pacemaker pocket has an alternative diagnosis, which is exemplified by the following case.

Case summary

A 70-year-old male patient had a-specific symptoms of fatigue, dyspnoea, and coughing for some weeks. He also noted an evident, new swelling of his pacemaker pocket several months after pacemaker implantation, a procedure that was performed in a high-volume center and without any complication. Ultrasound imaging of the pocket suggested the presence of a soft tissue mass with increased vascularity, rather than a fluid collection or a late organized haematoma. Ultrasound-guided biopsy of the mass was obtained for histopathology analysis and revealed a well-differentiated invasive squamous cell carcinoma. Additional PET-CT imaging demonstrated multiple fluorodeoxyglucose-avid hotspots: a voluminous lesion in the left lung hilum, smaller lesions in the liver, some mediastinal lymph nodes, several bone lesions, and a large mass surrounding the pacemaker. The multidisciplinary oncologic specialty team concluded that the patient had an aggressive metastatic lung carcinoma. The patient refused to undergo further treatment and died 1.5 months after diagnosis.

Discussion

To the best of our knowledge, we did not find any earlier reports of a squamous cell carcinoma of the lung spreading to a pacemaker pocket. Presentation of a primary tumour or a metastasis in a pacemaker pocket is extremely rare. Ultrasound imaging with ultrasound-guided biopsy is a fast and reliable method to sample the tissue and to obtain a reliable diagnosis.

Initial experience of left bundle branch area pacing using stylet-driven pacing leads: a multicenter study

Funding Acknowledgements

Type of funding sources: None.

Background

Left bundle branch area pacing (LBBAP) has been performed exclusively using lumen-less pacing leads (LLL) with fixed helix design. This study is the first to explore in a multicenter population the safety and feasibility of LBBAP using stylet-driven leads (SDL) with extendable helix design.

Methods

This study prospectively enrolled all consecutive patients who underwent LBBAP for anti-bradycardia pacing or heart failure indications at 8 Belgian hospitals. LBBAP was attempted either using SDL or LLL delivered through dedicated delivery sheaths. Implant success, complications, procedural and pacing characteristics were recorded at implant and follow-up.

Results

The study enrolled 412 patients (mean age 74 ± 38 years, 44% female). LBBAP with SDL and LLL was successful in 334/353 (94%) and 52/59 (88%) respectively (p=0.058). Implant success for LBBAP using SDL varied from 93 to 100% among centers. Mean paced QRS duration and stimulus to left ventricular activation time were comparable for SDL and LLL (126 ± 21ms versus 125 ± 22ms, p=0.861 and 74 ± 17 and 75 ± 21ms, p=0.756). SDL LBBAP resulted in low pacing thresholds (0.6 ± 0.4V at 0.4ms), which remained stable at 1, 6 and 12 months of follow-up. Lead revisions for SDL LBBAP occurred in 5(1.4%) patients: 2 dislodgements at day 1, 1 late septal perforation at week 3, 1 Twiddler’s syndrome at 5 months, 1 lead fracture at 6 months.

Conclusion

This multicenter study confirms the safety and feasibility of LBBAP using SDL, which is characterized by high implant success, low complication rate and low and stable pacing thresholds.

Arrhythmic Storm Due to ICD Atrial Lead Malfunction

We describe the case of a young woman with a dual-chamber implantable cardioverter-defibrillator for long-QT syndrome who was referred to our emergency department (Cardiovascular Research Centre of Aalst, Belgium) because of an “arrhythmic storm” caused by atrial lead fracture. This case highlights the importance of the correct choice of both the device type and the pacing modality. (Level of Difficulty: Intermediate.)

Performance of non-invasive myocardial work to predict the first hospitalization for de novo heart failure with preserved ejection fraction (HFpEF)

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): Dr. Paolisso, Dr. Esposito, Dr. Fabbricatore are supported by a research grant from the CardioPaTh PhD Program of University of Naples Federico II

Background

Non-invasive myocardial work (MW) is a validated index of left ventricular (LV) systolic performance, incorporating afterload and myocardial metabolism. The role of MW in predicting the first hospitalization for de novo heart failure with preserved ejection fraction (HFpEF) is still unknown.

Purpose

To investigate the diagnostic performance of MW to predict the first de novo HFpEF hospitalization in ambulatory individuals with preserved LVEF.

Methods

Twenty-nine patients with trans-thoracic echocardiography performed at least 6 months before the first HFpEF hospitalization were compared with 29 matched controls. MW was derived as the area of pressure-strain loop using speckle-tracking and brachial artery blood pressure. Global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were collected. First HFpEF hospitalization and its combination with cardiovascular death (MACE) and all-cause of death (MAE) were assessed.

Results

At baseline, future HFpEF patients showed lower GWI, GCW, GWE and higher GWW than controls (all p &lt; 0.05).  At admission versus baseline, GWE significantly decreased, and GWW increased in the HFpEF group (p &lt; 0.05), whereas no significant difference was observed in the controls over time. GWW, with a cut-off of 170 mmHg%, showed the largest AUC to predict first HFpEF hospitalization (AUC = 0.80, 95% CI 0.69–0.91, p &lt; 0.001), MACE (AUC = 0.80, 95% CI 0.66–0.90, p &lt; 0.001) and MAE (AUC = 0.79, 95% CI 0.62–0.88, p = 0.001). GWW &gt; 170 mmHg% was associated with a 4-fold increase of MACE (HR = 4.5, 95% CI 1.59–13.12, p = 0.005) and a 3-fold higher risk of MAE (HR = 2.9, 95% CI 1.24–6.6, p = 0.014).

Conclusions

In ambulatory patients with preserved LVEF and risk factors, GWW showed high accuracy to predict the first HFpEF hospitalization and its combination with mortality. The GWW routine assessment may be clinically helpful in patients with dyspnea. Abstract Figure 1: Serial changes of LARs, LV GLS  Abstract Figure 2:Kaplan–Meier survival curves fo

Performance of non-invasive myocardial work to predict the first hospitalization for de novo heart failure with preserved ejection fraction

AIMS

Non-invasive myocardial work (MW) is a validated index of left ventricular (LV) systolic performance, incorporating afterload and myocardial metabolism. The role of MW in predicting the first hospitalization for de novo heart failure with preserved ejection fraction (HFpEF) is still unknown. We aim to investigate the diagnostic performance of MW to predict the first de novo HFpEF hospitalization in ambulatory individuals with preserved LV ejection fraction.

METHODS AND RESULTS

Twenty-nine patients with transthoracic echocardiography performed at least 6 months before the first HFpEF hospitalization were compared with 29 matched controls. MW was derived as the area of pressure-strain loop using speckle-tracking and brachial artery blood pressure. Global work index, global constructive work, global wasted work (GWW), and global work efficiency (GWE) were collected. First HFpEF hospitalization and its combination with cardiovascular death [major adverse cardiovascular events (MACE)] and all-cause of death [major adverse events (MAE)] were assessed. At baseline, future HFpEF patients showed lower global work index, global constructive work, GWE, and higher GWW than controls (all P < 0.05). At admission vs. baseline, GWE significantly decreased, and GWW increased in the HFpEF group (P < 0.05), whereas no significant difference was observed in the controls over time. GWW, with a cut-off of 170 mmHg%, showed the largest area under the curve (AUC) to predict first HFpEF hospitalization [AUC = 0.80, 95% confidence interval (CI) 0.69-0.91, P < 0.001], MACE (AUC = 0.80, 95% CI 0.66-0.90, P < 0.001), and MAE (AUC = 0.79, 95% CI 0.62-0.88, P = 0.001). GWW > 170 mmHg% was associated with a 4-fold increase of MACE (HR = 4.5, 95% CI 1.59-13.12, P = 0.005) and a 3-fold higher risk of MAE (HR = 2.9, 95% CI 1.24-6.6, P = 0.014).

CONCLUSIONS

In ambulatory patients with preserved LV ejection fraction and risk factors, GWW showed high accuracy to predict the first HFpEF hospitalization and its combination with mortality. The GWW routine assessment may be clinically helpful in patients with dyspnoea.

Risk of myocardial infarction based on endothelial shear stress analysis using coronary angiography

BACKGROUND AND AIMS

Wall shear stress (WSS) has been associated with atherogenesis and plaque progression. The present study assessed the value of WSS analysis derived from conventional coronary angiography to detect lesions culprit for future myocardial infarction (MI).

METHODS AND RESULTS

Three-dimensional quantitative coronary angiography (3DQCA), was used to calculate WSS and pressure drop in 80 patients. WSS descriptors were compared between 80 lesions culprit of future MI and 108 non-culprit lesions (controls). Endothelium-blood flow interaction was assessed by computational fluid dynamics (10.8 ± 1.41 min per vessel). Median time between baseline angiography and MI was 25.9 (21.9-29.8) months. Mean patient age was 70.3 ± 12.7. Clinical presentation was STEMI in 35% and NSTEMI in 65%. Culprit lesions showed higher percent area stenosis (%AS), translesional vFFR difference (ΔvFFR), time-averaged WSS (TAWSS) and topological shear variation index (TSVI) compared to non-culprit lesions (p < 0.05 for all). TSVI was superior to TAWSS in predicting MI (AUC-TSVI = 0.77, 95%CI 0.71-0.84 vs. AUC-TAWSS = 0.61, 95%CI 0.53-0.69, p < 0.001). The addition of TSVI increased predictive and reclassification abilities compared to a model based on %AS and ΔvFFR (NRI = 1.04, p < 0.001, IDI = 0.22, p < 0.001).

CONCLUSIONS

A 3DQCA-based WSS analysis was feasible and can identify lesions culprit for future MI. The combination of area stenoses, pressure gradients and WSS predicted the occurrence of MI. TSVI, a novel WSS descriptor, showed strong predictive capacity to detect lesions prone to cause MI.

Circulating SERPINA3 improves prognostic stratification in patients with a de novo or worsened heart failure

Aims

We investigated the prognostic relevance of serpin peptidase inhibitor, clade A member 3 (SERPINA3) in patients admitted with a de novo or worsened heart failure (HF).

Methods and results

In the first stage, 83 HF‐related left ventricular (LV) transcripts were examined in patients with congestive cardiomyopathy (CCMP, n = 44) who died within 5 years and compared with age‐matched and haemodynamically matched CCMP survivors (n = 39) and controls with normal LV function (n = 17). Among 14 differentially expressed transcripts, myocardial gene and circulating SERPINA3 levels were up‐regulated in non‐survivors vs. survivors (2.40 ± 3.66 vs. 0.36 ± 0.22 units, P < 0.01 and 334.7 ± 138.7 vs. 228.2 ± 83.1 μg/mL, P < 0.01, respectively). While no significant transmyocardial gradient was detected, cytokine stimulation of human endothelial cells induced SERPINA3 secretion. In an independent validation cohort with a de novo or worsened HF (n = 387), circulating SERPINA3 levels > 316 μg/mL were associated with increased all‐cause mortality {hazard ratio [HR] [95% confidence interval (CI)]: 2.4 [1.5–3.9], P = 0.0002} and its composite with unplanned cardiovascular readmission [HR (95% CI): 2.0 (1.2–3.3), P = 0.004]. Patients with elevated SERPINA3 levels and elevated either N‐terminal pro brain natriuretic peptide or ST2 showed worse freedom from both endpoints. In a multivariate analysis, including established clinical risk factors, SERPINA3 remained independent predictor of all‐cause mortality together with age, gender, ST2, glomerular filtration, and pulmonary capillary wedge pressure.

Conclusion

In patients with a de novo or worsened HF, increased SERPINA3 levels > 316 μg/mL are associated with increased mortality or unplanned cardiac readmission. Elevated SERPINA3 levels on top of established clinical predictors appear to identify a subgroup of HF patients at higher mortality risk. Prospective studies should further validate its value in prognostic stratification of HF.

Deep learning for mortality prediction in patients with a de-novo or worsened heart failure

Background

Heart failure (HF) is a heterogenous syndrome with complex pathophysiology. Biomarkers and clinical risk scores often fail to provide optimal patient-level precision in the prognostic stratification. As utilizing single observational timepoint, they do not capture the entire care pathway with variations in individual patient management. Electronic patient records provide an opportunity to develop new artificial intelligence (AI) strategies for comprehensive prognostic re-stratification reflecting diagnostic and therapeutic management.

Purpose

We sought to use deep artificial intelligence (AI) and develop an unbiased predictive algorithm for all-cause mortality in a cohort of patients hospitalized with a de novo or worsened HF.

Methods

In a cohort of 2449 HF patients hospitalized between 2011–2017, we utilized 151 451 patient exams from 422 parameters. They included clinical phenotyping, medication, ECG, laboratory, echocardiography, catheterization data or percutaneous and surgical interventions gathered on a routine clinical basis reflecting standard of care as captured in individual electronic records. The AI model development consisted of 101 iterations of repeated random subsampling splits into balanced training and validation sets.

Results

AI models yielded performance ranging from 0.83 to 0.89 AUC on the outcome-balanced validation set in predicting all-cause mortality at 30-, 90-, 180-, 360- and 720-day time-limits (Figure 1). The primary endpoint, 1-year mortality prediction model, recorded an 0.85 AUC accuracy. We observed stable model performance across all HF phenotypes: HFpEF 0.83 AUC, HFmrEF 0.85 AUC and HFrEF 0.86 AUC, respectively).

Conclusion

Our findings present a novel, patient-level, AI-based risk prediction of all-cause mortality in heart failure with a robust accuracy across its phenotypes. This suggests the potential of AI based predictive models in a point-of-care approach to guide clinical risk stratification.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): VZW Cardiovascular Research Center Aalst

Role of myocardial work index in early detection of cardiotoxicity in breast cancer patient

Introduction

Breast cancer patients receiving anthracyclines are particularly prone to develop cancer therapeutics-related cardiac dysfunction. Early detection of cardiotoxicity onset is required for optimal timing of cardio protection treatment. The latest guidelines consider a relative reduction of 15% in global longitudinal strain (GLS) from baseline as risk for cardiotoxicity. Nevertheless, the more recent Myocardial Work Index (MWI) offers a load-independent tool for detection of subclinical heart failure (HF). However, data in cancer patients are still scarce.

Purpose

This study analyses the predictive value of MWI for cardiotoxicity diagnosis after 6 months chemotherapy.

Methods

The study population consists of breast cancer patients referred for chemotherapy with anthracyclines and taxanes. Patients with a history of HF previous to chemotherapy or depressed LV function at baseline were excluded. Echocardiography was performed before onset of the chemotherapy (baseline) and after 6 months follow-up. LVEF, GLS and MWI were assessed offline using EchoPAC software. The values at baseline and 6 months follow-up were pairwise compared to detect subclinical cardiac dysfunction. LVEF, GLS and MWI means at baseline were taken as cut-off to compare the predictive value of each parameter. Moreover, patients were categorized in one group with GLS reduction &gt;15% (Group 1) and one group with GLS reduction &lt;15% (Group 2).

Results

From April 2016 to July 2020, 28 women with breast cancer were included (age 54±11 years, LVEF 58±4%, GLS −21±2%, MWI 2160±308 mmHg). All patients underwent the same standard chemotherapy protocol (4xEC, 12xTaxol). No difference in baseline characteristics between group 1 (n=13) and group 2 (n=15) was observed. At 6 months follow up a significant decrease in LVEF (53±8%, p=0.003), GLS (−19±3%, p=0.002) and MWI (1920±391 mmHg, p=0.005) was shown without any change in blood pressure. However, while mean LVEF and GLS at baseline did not predict any significant change, patients with MWI under the mean value at baseline (n=15) presented significant lower LVEF (50±8 vs 57±6% p=0.006), GLS (−17±3 vs −20±2%, p=0.01), MWI (1733±320 vs 2136±362 mmHg, p=0.005) after 6 months. Additionally, both groups had similar MWI at baseline (2148±335 mmHg vs 2170±294 mmHg, p=0.85), whereas those patients with GLS reduction &gt;15% showed significant lower MWI after 6 months (1694±332 mmHg vs 2116±334 mmHg, p=0.003, Figure 1).

Conclusions

At 6 months follow up, a decline of the LV systolic function as side effect of chemotherapy can be seen. MWI at baseline shows the best predictive value for development of cardiotoxicity, in comparison to LVEF and GLS. Further studies are warranted to better understand the role of MWI for early detection of cardiotoxicity and its clinical relevance.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): Onze-Lieve-Vrouw hospital in Aalst (Belgium)

Diagnosis and immunosuppressive treatment of inflammatory cardiomyopathy: a case report

Objectives: Definite diagnosis of myocarditis requires an endomyocardial biopsy (EMB) showing an inflammatory infiltrate. However, there are important limitations on establishing the diagnosis solely upon histological criteria. The main objective of this case report is to highlight the difficulty of diagnosis, but also to evaluate treatment in virus-negative inflammatory cardiomyopathy.Case report: We present the case of a 53-year-old man with an inflammatory cardiomyopathy based on cardiac magnetic resonance (CMR) findings consistent with extensive myocardial inflammation and a significantly depressed left ventricular ejection fraction (LVEF). Treatment with immunosuppressive therapy resulted in improvement of cardiac function and performance status, while also eliminating the need for ICD implantation.Conclusion: Cardiac magnetic resonance (CMR) has a high diagnostic accuracy and has become the primary diagnostic tool for noninvasive assessment of suspected myocarditis. EMBs should be analyzed using immunohistochemistry and viral polymerase chain reaction to increase the diagnostic sensitivity of histology. Immunosuppressive therapy should be considered in virus-negative inflammatory cardiomyopathy.

Validation of Coronary Angiography-Derived Vessel Fractional Flow Reserve in Heart Transplant Patients with Suspected Graft Vasculopathy

Cardiac transplant-related vasculopathy remains a leading cause of morbidity and mortality in heart transplant (HTx) recipients. Recently, coronary angiography-derived vessel fractional flow reserve (vFFR) has emerged as a new diagnostic computational tool to functionally evaluate the severity of coronary artery disease. Although vFFR estimates have been shown to perform well against invasive FFR in atherosclerotic coronary artery disease, data on the use of vFFR in heart transplant recipients suffering from cardiac transplant-related arteriopathy are lacking. The aim of the presented study was to validate coronary angiography-derived vessel fractional flow reserve to calculate fractional flow reserve in HTx patients with and without cardiac transplant-related vasculopathy. A prospective, single center study of HTx patients referred for annual check-up, undergoing surveillance coronarography was conducted. Invasive FFR was measured using a motorized device at the speed of 1.0 mm/s in all three major coronary arteries. Angiography-derived pullback FFR was derived from the angiogram and compared with invasive FFR pullback curve. Overall, 18,059 FFR values were extracted from the FFR pullback curves from 23 HTx patients. The mean age was 59.3 ± 9.7 years, the mean time after transplantation was 5.24 years [IQR 1.20, 11.25]. A total of 39 vessels from 23 patients (24 LAD, 11 LCX, 4 RCA) were analyzed. Mean distal vFFR was 0.87 ± 0.14 whereas invasive distal FFR was 0.88 ± 0.17. An excellent correlation was found between invasive distal FFR and vFFR (r = 0.92; p < 0.001). The correlation of the pullback tracing was high, with a correlation coefficient between vFFR and invasive FFR pullback values of 0.72 (95% CI 0.71 to 0.73, p < 0.001). The mean difference between vFFR and invasive FFR pullback values was -0.01 with 0.06 of SD (limits of agreements -0.12 to 0.13). In HTx patients, coronary angiography-derived FFR correlates excellently with invasively measured wire-derived FFR. Therefore, angiography derived FFR could be used as a novel diagnostic tool to quantify the functional severity of graft vasculopathy.

Clinical symptoms of limited exercise capacity linked to AAI-DDD functionality: An in silico and in vivo approach

BACKGROUND

Exercise capacity is an important aspect of quality of life in patients undergoing pacemaker implantation. Device algorithms for ventricular pacing avoidance have been developed to avoid unnecessary and potentially harmful effects of right ventricular pacing. However, little data exists on the immediate response of these algorithms to sudden AV block during exercise.

METHODS

The ventricular pacing avoidance algorithms of four pacemaker manufacturers were tested in an ex-vivo model. The RSIM-1500-USB Device-Interactive Heart Simulator (Rivertek Medical Systems, Inc.) was used to simulate three different scenarios: the first one starting with an initially conducted atrial pacing rate of 60 min^-1 , the second one starting with an atrial rate of 120 min^-1 and finally a scenario starting with an atrial rate of 150 min^-1 . In all three scenarios, the initially conducted atrial rate was followed by a sudden, long lasting episode of third-degree AV-block. The response to those scenarios was recorded for each of the (brand-specific) ventricular pacing avoidance algorithms.

RESULTS

In the first scenario, the simulation resulted in a ventricular pause of 1333 ms (Boston Scientific), 2000 ms (Medtronic and Microport), and 2340 ms (Biotronik). In the second and third scenario, different results were observed across devices. All simulations of the second and third scenario resulted in repetitive 2:1 block response (during eight cycles) in Boston Scientific and Biotronik devices. These scenarios were confirmed in patient cases.

CONCLUSION

Simulator based observations of unanticipated pacemaker-induced 2:1 block response during exercise may explain clinical symptoms experienced by some patients having a two-chamber pacemaker.

Rationale and design of the precise percutaneous coronary intervention plan (P3) study: Prospective evaluation of a virtual computed tomography-based percutaneous intervention planner

Introduction

Fractional flow reserve (FFR) measured after percutaneous coronary intervention (PCI) has been identified as a surrogate marker for vessel related adverse events. FFR can be derived from standard coronary computed tomography angiography (CTA). Moreover, the FFR derived from coronary CTA (FFR_CT) Planner is a tool that simulates PCI providing modeled FFR_CT values after stenosis opening.

Aim

To validate the accuracy of the FFR_CT Planner in predicting FFR after PCI with invasive FFR as a reference standard.

Methods

Prospective, international and multicenter study of patients with chronic coronary syndromes undergoing PCI. Patients will undergo coronary CTA with FFR_CT prior to PCI. Combined morphological and functional evaluations with motorized FFR hyperemic pullbacks, and optical coherence tomography (OCT) will be performed before and after PCI. The FFR_CT Planner will be applied by an independent core laboratory blinded to invasive data, replicating the invasive procedure. The primary objective is to assess the agreement between the predicted FFR_CT post‐PCI derived from the Planner and invasive FFR. A total of 127 patients will be included in the study.

Results

Patient enrollment started in February 2019. Until December 2020, 100 patients have been included. Mean age was 64.1 ± 9.03, 76% were males and 24% diabetics. The target vessels for PCI were LAD 83%, LCX 6%, and RCA 11%. The final results are expected in 2021.

Conclusion

This study will determine the accuracy and precision of the FFR_CT Planner to predict post‐PCI FFR in patients with chronic coronary syndromes undergoing percutaneous revascularization.

Myocardial work index: a novel tool for detection of early cardiotoxicity in breast cancer patient

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): Cardiovascular Research Center Aalst, (Aalst, Belgium)

Introduction

Breast cancer patients receiving anthracyclines are particularly prone to develop cancer therapeutics-related cardiac dysfunction (CTRCD). Early detection of cardiotoxicity onset is required for optimal timing of cardio protection treatment. The latest guidelines consider a relative reduction of 15% in global longitudinal strain (GLS) from baseline as risk for cardiotoxicity. Nevertheless, the more recent Myocardial Work Index (MWI) offers a load-independent tool for detection of subclinical heart failure (HF). Data in cancer patients are still scarce. 

Purpose

This study analyses the predictive value of MWI for cardiotoxicity diagnosis after 6 months chemotherapy.

Methods

The study population consists of breast cancer patients referred for chemotherapy with anthracyclines and taxanes. Patients with a history of HF previous to chemotherapy or depressed LV function at baseline were excluded. Echocardiography was performed before onset of the chemotherapy (baseline) and after 6 months follow-up. LVEF, GLS and MWI were assessed offline using EchoPAC software. The values at baseline and 6 months follow-up were pairwise compared to detect subclinical cardiac dysfunction. Mean LVEF, GLS and MWI at baseline were taken as cut-off value to compare the predictive value of each parameter. Moreover, patients were categorized in one group with GLS reduction &gt;15% (Group 1) and one group with GLS reduction &lt;15% (Group 2).  

Results

From April 2016 to January 2020, 24 women with breast cancer were included (age 54 ± 11 years, LVEF 58 ± 4%, GLS -21 ± 2%, MWI 2181 ± 325 mmHg). All patients underwent the same standard chemotherapy protocol (4xEC, 12xTaxol). No difference in baseline characteristics between group 1 (n = 9) and group 2 (n = 15) was observed. At 6 months follow up a significant decrease in LVEF (53 ± 8%, p = 0.003), GLS (-19 ± 3%, p = 0.002) and MWI (1933 ± 410 mmHg, p = 0.005) was shown without any change in blood systolic pressure. However, while mean LVEF and GLS at baseline did not predict any significant change, patients with MWI under the mean value at baseline (n = 13) presented significant lower LVEF (49 ± 8%, p = 0.006), GLS (-18 ± 4%, p = 0.045), MWI (1753 ± 341 mmHg, p = 0.018) after 6 months. Additionally, both groups had similar MWI at baseline (2199 ± 390 mmHg vs 2170 ± 294 mmHg, p = 0.85), whereas those patients with GLS reduction &gt;15% showed significant lower MWI after 6 months (1626 ± 344 mmHg vs 2116 ± 334 mmHg, p = 0.003, Figure 1).

Conclusions

At 6 months follow up, a decline of the LV systolic function as side effect of chemotherapy can be seen. In comparison to LVEF and GLS, MWI shows the best predictive value for development of early cardiotoxicity. Further studies are warranted to better understand the role of MWI in predicting CTRCD and its clinical relevance.

Abstract Figure. Change in MWI

Biomarkers to predict the response to cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) is an established non-pharmacological treatment for selected heart failure patients with wide QRS duration. However, there is a persistent number of non-responders throughout. The prediction of the CRT response is paramount to adequately select the correct patients for CRT. One of the expanding fields of research is the development of biomarkers that predict the response to CRT. A review of the available literature on biomarkers in CRT patients has been performed to formulate a critical appraisal of the available data. The main conclusion of our review is that biomarker research in this patient population is very fragmented and broad. This results in the use of non-uniform endpoints to define the CRT response, which precludes an in-depth comparison of the available data. To improve research development in this field, a uniform definition of the CRT response and relevant endpoints is necessary to better predict the CRT response.

Progressive Thinning of the Basal Interventricular Septum by Giant Cell Myocarditis

We describe a patient with ventricular tachycardia and complete atrioventricular block. Remarkable thinning of the basal interventricular septum preceded left ventricular dysfunction. Endomyocardial biopsy demonstrated giant cell myocarditis. The patient received combined immunosuppressive therapy and a cardioverter-defibrillator. Eligibility screening for heart transplantation was initiated. (Level of Difficulty: Advanced.)

P6316Hemodynamic response to rapid saline loading in heart transplant recipients

Introduction

A pulmonary capillary wedge pressure (PCWP) ≥25 mm Hg following volume load or exercise has been proposed as a partition value for detection of HfpEF. However, the hemodynamic response to volume challenge in heart transplant (Tx) recipients has never been studied.

Methods

24 heart Tx recipients (age: 65 years) with normal LV function (55±7%) and without rejection and graft vasculopathy underwent right heart catheterization to measure hemodynamic response to volume loading before and after a rapid saline infusion of 7mL/kg over 10 min. PCWP, right atrial pressure (RAP), mean pulmonary artery pressure (AP) were obtained and the PCWP and indexed (i) stroke volume (SV) data were used to construct Starling (SVindex/PCWP) curves. Pts were categorized in those with elevated filling pressures (Group A, n=13 pts) defined by a PCWP ≥15 mm Hg at rest or ≥25 mm Hg following volume loading vs those without (Group B, n=11 pts).

Results

No difference in age of donor and transplant heart, baseline hemodynamics and EF was noted between both groups. Saline infusion significantly increased PCWP and mean AP in both Groups (table 1) without any significant change in BP and heart rate. Interestingly saline infusion was associated with a significant rise in SV and SVi in Group B not in Group A pts. Moreover, in Group B pts the Starling curves revealed a larger SVi at any give PCWP compared to Group A pts (Fig.1).

Table 1 All (n=24) Group A (n=13) Group B (n=11) Baseline Volume Loading Baseline Volume Loading Baseline Volume Loading RAP (mm Hg) 5.3±4.1 9.2±4.8* 7.6±4.8 11.4±5.2* 3.8±2.5 7.3±1.9* Mean AP 18.4±5.4 24.1±5.9* 21.7±5.1 26.8±6.5** 14.9±2.4 20.8±2.6* PCWP 12.1±4.9 16.8±6.7* 15.0±4.9 19.8±6.5** 8.4±1.9 14.6±3.7* SV 71.4±19.6 72.5±23.6 73.2±6.2 72.4±6.2 69.2±14.6 79.2±3.9 SViml/m2) 37.4±9.2 37.9±11.2 36.7±7.1 38.7±9.9 35.3±6.0 40.5±5.2* *p<0.01 compared to baseline; **p<0.05 compared to baseline.

Figure 1

Conclusions

In the transplanted heart volume loading increases filling pressures and is able to unmask left ventricular diastolic dysfunction. Interestingly, those with HFpEF are characterized by a blunted Frank Starling response as evidenced by higher PCWP and failure to increase SV for any given PCWP. Further prospective studies are warranted to unravel the underlying mechanisms.

Impact of non-invasive anatomical testing on optimal medical prescription in patients with suspected coronary artery disease

Background

Compared to functional testing, coronary computed tomography angiography (CTA) improves clinical outcomes in patients with suspected coronary artery disease (CAD). This is thought to be the result of an increased prescription of preventive medical therapy (statins and aspirin) when relying on a CTA imaging strategy. We compared the rate of statins prescription in a patient cohort assessed either with coronary CTA or exercise testing, and evaluated the agreement on medication prescriptions.

Methods

Consecutive patients who underwent coronary CTA and exercise test for suspected CAD were included. Four clinical cardiologists independently analysed each case based on clinical information and the result of either coronary CTA or exercise test. For each case, treatment strategy and prescription were recorded while blinded to the results of the other cardiac test. Treatment strategy was reassessed using the alternative imaging modality three weeks after the first evaluation.

Results

A total of 113 patients were included. Mean age was 56.7±11.5 years, 52% were males and diabetes were present in 6%. Coronary CTA showed an obstructive epicardial stenosis in 21.4% and any type of atherosclerotic plaque in 54.2%. Functional testing identified ischemia in 9.1%. The use of coronary CTA resulted in higher number of statin (64.9% vs. 44.5%, P<0.001) and aspirin (21.4% vs. 4.3%, P<0.001) prescriptions. There was a substantial agreement on the prescription of statins (mean Cohen's κ coefficient of 0.79±0.07).

Conclusions

Epicardial atherosclerotic disease was found in half of patients with suspected CAD as assessed by coronary CTA. Compared to functional testing, coronary CTA evaluation by coronary was associated with an increase in the rate preventive therapy prescription.

Monitoring reperfused myocardial infarction with delayed left ventricular systolic dysfunction in rabbits by longitudinal imaging

Background

An experimental imaging platform for longitudinal monitoring and evaluation of cardiac morphology-function changes has been long desired. We sought to establish such a platform by using a rabbit model of reperfused myocardial infarction (MI) that develops chronic left ventricle systolic dysfunction (LVSD) within 7 weeks.

Methods

Fifty-five New Zeeland white (NZW) rabbits received sham-operated or 60-min left circumflex coronary artery (LCx) ligation followed by reperfusion. Cardiac magnetic resonance imaging (cMRI), transthoracic echocardiography (echo), and blood samples were collected at baseline, in acute (48 hours or 1 week) and chronic (7 weeks) stage subsequent to MI for in vivo assessment of infarct size, cardiac morphology, LV function, and myocardial enzymes. Seven weeks post MI, animals were sacrificed and heart tissues were processed for histopathological staining.

Results

The success rate of surgical operation was 87.27%. The animal mortality rates were 12.7% and 3.6% both in acute and chronic stage separately. Serum levels of the myocardial enzyme cardiac Troponin T (cTnT) were significantly increased in MI rabbits as compared with sham animals after 4 hours of operation (P<0.05). According to cardiac morphology and function changes, 4 groups could be distinguished: sham rabbits (n=12), and MI rabbits with no (MI_NO_LVSD; n=10), moderate (MI_M_LVSD; n=9) and severe (MI_S_LVSD; n=15) LVSD. No significant differences in cardiac function or wall thickening between sham and MI_NO_LVSD rabbits were observed at both stages using both cMRI and echo methods. cMRI data showed that MI_M_LVSD rabbits exhibited a reduction of ejection fraction (EF) and an increase in end-systolic volume (ESV) at the acute phase, while at the chronic stage these parameters did not change further. Moreover, in MI_S_LVSD animals, these observations were more striking at the acute stage followed by a further decline in EF and increase in ESV at the chronic stage. Lateral wall thickening determined by cMRI was significantly decreased in MI_M_LVSD versus MI_NO_LVSD animals at both stages (P<0.05). As for MI_S_LVSD versus MI_M_LVSD rabbits, the thickening of anterior, inferior and lateral walls was significantly more decreased at both stages (P<0.05). Echo confirmed the findings of cMRI. Furthermore, these in vivo outcomes including those from vivid cine cMRI could be supported by exactly matched ex vivo histomorphological evidences.

Conclusions

Our findings indicate that chronic LVSD developed over time after surgery-induced MI in rabbits can be longitudinally evaluated using non-invasive imaging techniques and confirmed by the entire-heart-slice histomorphology. This experimental LVSD platform in rabbits may interest researchers in the field of experimental cardiology and help strengthen drug development and translational research for the management of cardiovascular diseases.

NF-κB-mediated metabolic remodelling in the inflamed heart in acute viral myocarditis

Acute viral myocarditis (VM), characterised by leukocyte infiltration and dysfunction of the heart, is an important cause of sudden cardiac death in young adults. Unfortunately, to date, the pathological mechanisms underlying cardiac failure in VM remain incompletely understood. In the current study, we investigated if acute VM leads to cardiac metabolic rewiring and if this process is driven by local inflammation. Transcriptomic analysis of cardiac biopsies from myocarditis patients and a mouse model of VM revealed prominent reductions in the expression of a multitude of genes involved in mitochondrial oxidative energy metabolism. In mice, this coincided with reductions in high-energy phosphate and NAD levels, as determined by Imaging Mass Spectrometry, as well as marked decreases in the activity, protein abundance and mRNA levels of various enzymes and key regulators of cardiac oxidative metabolism. Indicative of fulminant cardiac inflammation, NF-κB signalling and inflammatory cytokine expression were potently induced in the heart during human and mouse VM. In cultured cardiomyocytes, cytokine-mediated NF-κB activation impaired cardiomyocyte oxidative gene expression, likely by interfering with the PGC-1 (peroxisome proliferator-activated receptor (PPAR)-γ co-activator) signalling network, the key regulatory pathway controlling cardiomyocyte oxidative metabolism. In conclusion, we provide evidence that acute VM is associated with extensive cardiac metabolic remodelling and our data support a mechanism whereby cytokines secreted primarily from infiltrating leukocytes activate NF-κB signalling in cardiomyocytes thereby inhibiting the transcriptional activity of the PGC-1 network and consequently modulating myocardial energy metabolism.

Antioxidant Treatment Improves Cardiac Dysfunction in a Murine Model of Premature Aging

Bmal1-(brain and muscle ARNT-like protein-1) deficient (Bmal1) mice prematurely age because of an increased reactive oxygen species (ROS) production. These mice also show a decline in cardiac function with age. We investigated whether an antioxidant treatment can ameliorate the declining cardiac function in prematurely aged Bmal1 mice. Male Bmal1 and wild-type (Bmal1) mice were exposed for 15 weeks to a high fat and high cholesterol diet with or without the antioxidant 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPOL; 5 mmol/L; in drinking water during the last 10 weeks). Echocardiographic analysis revealed that TEMPOL treatment of Bmal1 mice normalized cardiac function, as evidenced by a decrease in left ventricular diastolic and systolic internal diameters, and by an increase in fractional shortening and ejection fraction. The antioxidant did not affect cardiac function in Bmal1 mice. Although TEMPOL did not influence cardiac ROS levels in Bmal1 mice, it significantly protected Bmal1 cardiac telomeres from oxidation, as evidenced by a reduction in the telomere damage score (0.11 ± 0.012% vs. 0.16 ± 0.015%; P = 0.028). Thus, antioxidant treatment normalized cardiac function of Bmal1 mice, probably in part by scavenging ROS.

RNA Profiling in Human and Murine Transplanted Hearts: Identification and Validation of Therapeutic Targets for Acute Cardiac and Renal Allograft Rejection

Acute cellular rejection (ACR) is the adverse response of the recipient's immune system against the allogeneic graft. Using human surveillance endomyocardial biopsies (EMBs) manifesting ACR and murine allogeneic grafts, we profiled implicated microRNAs (miRs) and mRNAs. MiR profiling showed that miR-21, -142-3p, -142-5p, -146a, -146b, -155, -222, -223, and -494 increased during ACR in humans and mice, whereas miR-149-5p decreased. mRNA profiling revealed 70 common differentially regulated transcripts, all involved in immune signaling and immune-related diseases. Interestingly, 33 of 70 transcripts function downstream of IL-6 and its transcription factor spleen focus forming virus proviral integration oncogene (SPI1), an established target of miR-155, the most upregulated miR in human EMBs manifesting rejection. In a mouse model of cardiac transplantation, miR-155 absence and pharmacological inhibition attenuated ACR, demonstrating the causal involvement and therapeutic potential of miRs. Finally, we corroborated our miR signature in acute cellular renal allograft rejection, suggesting a nonorgan specific signature of acute rejection. We concluded that miR and mRNA profiling in human and murine ACR revealed the shared significant dysregulation of immune genes. Inflammatory miRs, for example miR-155, and transcripts, in particular those related to the IL-6 pathway, are promising therapeutic targets to prevent acute allograft rejection.

The microRNA-221/-222 cluster balances the antiviral and inflammatory response in viral myocarditis

Aims

Viral myocarditis (VM) is an important cause of heart failure and sudden cardiac death in young healthy adults; it is also an aetiological precursor of dilated cardiomyopathy. We explored the role of the miR-221/-222 family that is up-regulated in VM.

Methods and results

Here, we show that microRNA-221 (miR-221) and miR-222 levels are significantly elevated during acute VM caused by Coxsackievirus B3 (CVB3). Both miRs are expressed by different cardiac cells and by infiltrating inflammatory cells, but their up-regulation upon myocarditis is mostly exclusive for the cardiomyocyte. Systemic inhibition of miR-221/-222 in mice increased cardiac viral load, prolonged the viraemic state, and strongly aggravated cardiac injury and inflammation. Similarly, in vitro, overexpression of miR-221 and miR-222 inhibited enteroviral replication, whereas knockdown of this miR-cluster augmented viral replication. We identified and confirmed a number of miR-221/-222 targets that co-orchestrate the increased viral replication and inflammation, including ETS1/2, IRF2, BCL2L11, TOX, BMF, and CXCL12. In vitro inhibition of IRF2, TOX, or CXCL12 in cardiomyocytes significantly dampened their inflammatory response to CVB3 infection, confirming the functionality of these targets in VM and highlighting the importance of miR-221/-222 as regulators of the cardiac response to VM.

Conclusions

The miR-221/-222 cluster orchestrates the antiviral and inflammatory immune response to viral infection of the heart. Its inhibition increases viral load, inflammation, and overall cardiac injury upon VM.

Liver X receptor activation enhances CVB3 viral replication during myocarditis by stimulating lipogenesis

AIMS

Viral myocarditis (VM) is severe cardiac inflammation that can result in sudden death or congestive heart failure in previously healthy adults, with no effective therapy. Liver X receptor (LXR) agonists have both anti-inflammatory and lipid-lowering properties. This study investigates whether LXR agonist T0901317 may modulate viral replication and cardiac inflammation during VM.

METHODS AND RESULTS

(i) Adult mice were administered T0901317 or vehicle with the onset of inflammation during CVB3 virus myocarditis or (ii) treated 2 days prior to CVB3 infection. Against what we expected, T0901317 treatment did not alter leucocyte infiltration after CVB3 infection; yet pre-administration with T0901317 resulted in increased mortality upon CVB3 infection, higher cardiac viral presence, and increased cardiomyocyte damage when compared with the vehicle. Furthermore, we show a correlation of fatty acid synthase (FAS) and sterol regulatory element-binding protein 1c (SREBP-1c) with CVB3 viral load in the heart and that T0901317 is able to enhance the cardiac expression of FAS and SREBP-1c. Finally, we show in vitro that T0901317 is able to exaggerate CVB3-mediated damage of Vero cells, whereas inhibitors of FAS and the SREBP-1c reduce the viral presence of CVB3 in neonatal cardiomyocytes.

CONCLUSION

LXR agonism does not modulate cardiac inflammation, but exacerbates virus-mediated myocardial damage during VM by stimulating lipid biosynthesis and enhancing CVB3 replication.

Fatty acid carbon is essential for dNTP synthesis in endothelial cells

The metabolism of endothelial cells (ECs) during vessel sprouting remains poorly studied. Here, we report that endothelial loss of CPT1a, a rate-limiting enzyme of fatty acid oxidation (FAO), caused vascular sprouting defects due to impaired proliferation, not migration of ECs. Reduction of FAO in ECs did not cause energy depletion or disturb redox homeostasis, but impaired de novo nucleotide synthesis for DNA replication. Isotope labeling studies in control ECs showed that fatty acid carbons substantially replenished the Krebs cycle, and were incorporated into aspartate (a nucleotide precursor), uridine monophosphate (a precursor of pyrimidine nucleoside triphosphates) and DNA. CPT1a silencing reduced these processes and depleted EC stores of aspartate and deoxyribonucleoside triphosphates. Acetate (metabolized to acetyl-CoA, thereby substituting for the depleted FAO-derived acetyl-CoA) or a nucleoside mix rescued the phenotype of CPT1a-silenced ECs. Finally, CPT1 blockade inhibited pathological ocular angiogenesis, suggesting a novel strategy for blocking angiogenesis.

The thiazolobenzimidazole TBZE-029 inhibits enterovirus replication by targeting a short region immediately downstream from motif C in the nonstructural protein 2C

TBZE-029 {1-(2,6-difluorophenyl)-6-trifluoromethyl-1H,3H-thiazolo[3,4-a]benzimidazole} is a novel selective inhibitor of the replication of several enteroviruses. We show that TBZE-029 exerts its antiviral activity through inhibition of viral RNA replication, without affecting polyprotein processing. To identify the viral target of TBZE-029, drug-resistant coxsackievirus B3 (CVB3) was selected. Genotyping of resistant clones led to the identification of three amino acid mutations in nonstructural protein 2C, clustered at amino acid positions 224, 227, and 229, immediately downstream of NTPase/helicase motif C. The mutations were reintroduced, either alone or combined, into an infectious full-length CVB3 clone. In particular the mutations at positions 227 and 229 proved essential for the altered sensitivity of CVB3 to TBZE-029. Resistant virus exhibited cross-resistance to the earlier-reported antienterovirus agents targeting 2C, namely, guanidine hydrochloride, HBB [2-(alpha-hydroxybenzyl)-benzimidazole], and MRL-1237 {1-(4-fluorophenyl)-2-[(4-imino-1,4-dihydropyridin-1-yl)methyl]benzimidazole hydrochloride}. The ATPase activity of 2C, however, remained unaltered in the presence of TBZE-029.

Anti-enterovirus activity and structure–activity relationship of a series of 2,6-dihalophenyl-substituted 1H,3H-thiazolo[3,4-a]benzimidazoles

Despite the fact that enteroviruses are implicated in a variety of human diseases, there is no approved therapy for the treatment of enteroviral infections. Here, a series of 2,6-dihalophenyl-substituted 1H,3H-thiazolo[3,4-a]benzimidazoles with anti-enterovirus activity is reported. The compounds elicit potent activity against coxsackievirus A9, echovirus 9 and 11 and all six strains of coxsackievirus B. A structure-activity relationship analysis revealed that the presence of substituents at position 6 of the tricyclic system positively influences the antiviral activity, whereas substitutions at position 7 are less favorable. In particular a 6-trifluoromethyl substitution leads to a substantial improvement of the antiviral activity as compared to the unsubstituted structure. Furthermore, an additional introduction of a 2-Cl, 6-F substitution on the phenyl at C-1 results in a further increase of the antiviral activity. Hence, 1-(2-chloro-6-fluorophenyl)-6-trifluoromethyl-1H,3H-thiazolo[3,4-a]benzimidazole results in a dose-dependent inhibition of viral replication with a 50% effective concentration (EC50) of 0.41 microg/ml without any detectable cytotoxicity at the highest concentration (100 microg/ml) tested.