Impact of left ventricular unloading on postheart transplantation outcomes in patients bridged with VA-ECMO.

INTRODUCTION AND OBJECTIVES: The impact of preoperative left ventricular (LV) unloading on postoperative outcomes in patients bridged with venoarterial extracorporeal membrane oxygenation (VA-ECMO) to heart transplantation (HT) is unknown. Our aim was to compare posttransplant outcomes in patients bridged to HT with VA-ECMO, with or without the use of different mechanical strategies for LV decompression. METHODS: We conducted a retrospective analysis of the postoperative outcomes of consecutive HT candidates bridged with VA-ECMO, with or without concomitant LV unloading. Patients were included from 16 Spanish centers from 2010 to 2020. The primary endpoint was 1-year post-HT survival, which was assessed using Cox regression. RESULTS: Overall, 245 patients underwent high-emergency HT while supported with VA-ECMO. A mechanical strategy for LV unloading was used in 133 (54.3%) patients, with the intra-aortic balloon pump being the most commonly used method (n = 112; 84.2%). One-year posttransplant survival was 74.4% in the LV unloading group and 59.8% in the control group (P = .025). In multivariate analyses, preoperative LV unloading was independently associated with lower 1-year mortality (adjusted HR, 0.50; 95%CI, 0.32-0.78; P = .003). This association was observed both in patients managed with an intra-aortic balloon pump alone (adjusted HR, 0.52; 95%CI, 0.32-0.84; P = .007) and with other strategies for mechanical LV unloading (adjusted HR, 0.43; 95%CI, 0.19-0.97; P = .042). No significant differences were found between groups regarding other postoperative complications. CONCLUSIONS: Preoperative LV unloading was independently associated with increased 1-year posttransplant survival in candidates bridged with VA-ECMO.

Novel systematic processing of cardiac magnetic resonance imaging identifies target regions associated with infarct-related ventricular tachycardia.

AIMS: There is lack of agreement on late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) imaging processing for guiding ventricular tachycardia (VT) ablation. We aim at developing and validating a systematic processing approach on LGE-CMR images to identify VT corridors that contain critical VT isthmus sites. METHODS AND RESULTS: This is a translational study including 18 pigs with established myocardial infarction and inducible VT undergoing in vivo characterization of the anatomical and functional myocardial substrate associated with VT maintenance. Clinical validation was conducted in a multicentre series of 33 patients with ischaemic cardiomyopathy undergoing VT ablation. Three-dimensional LGE-CMR images were processed using systematic scanning of 15 signal intensity (SI) cut-off ranges to obtain surface visualization of all potential VT corridors. Analysis and comparisons of imaging and electrophysiological data were performed in individuals with full electrophysiological characterization of the isthmus sites of at least one VT morphology. In both the experimental pig model and patients undergoing VT ablation, all the electrophysiologically defined isthmus sites (n = 11 and n = 19, respectively) showed overlapping regions with CMR-based potential VT corridors. Such imaging-based VT corridors were less specific than electrophysiologically guided ablation lesions at critical isthmus sites. However, an optimized strategy using the 7 most relevant SI cut-off ranges among patients showed an increase in specificity compared to using 15 SI cut-off ranges (70 vs. 62%, respectively), without diminishing the capability to detect VT isthmus sites (sensitivity 100%). CONCLUSION: Systematic imaging processing of LGE-CMR sequences using several SI cut-off ranges may improve and standardize procedure planning to identify VT isthmus sites.

Reduced mitochondrial pyruvate carrier expression in hearts with heart failure and reduced ejection fraction patients: ischemic vs. non-ischemic origin.

Introduction and objectives: Mitochondrial pyruvate carrier (MPC) mediates the entry of pyruvate into mitochondria, determining whether pyruvate is incorporated into the Krebs cycle or metabolized in the cytosol. In heart failure (HF), a large amount of pyruvate is metabolized to lactate in the cytosol rather than being oxidized inside the mitochondria. Thus, MPC activity or expression might play a key role in the fate of pyruvate during HF. The purpose of this work was to study the levels of the two subunits of this carrier, named MPC1 and MPC2, in human hearts with HF of different etiologies. Methods: Protein and mRNA expression analyses were conducted in cardiac tissues from three donor groups: patients with HF with reduced ejection fraction (HFrEF) with ischemic cardiomyopathy (ICM) or idiopathic dilated cardiomyopathy (IDC), and donors without cardiac pathology (Control). MPC2 plasma levels were determined by ELISA. Results: Significant reductions in the levels of MPC1, MPC2, and Sirtuin 3 (SIRT3) were observed in ICM patients compared with the levels in the Control group. However, no statistically significant differences were revealed in the analysis of MPC1 and MPC2 gene expression among the groups. Interestingly, Pyruvate dehydrogenase complex (PDH) subunits expression were increased in the ICM patients. In the case of IDC patients, a significant decrease in MPC1 was observed only when compared with the Control group. Notably, plasma MPC2 levels were found to be elevated in both disease groups compared with that in the Control group. Conclusion: Decreases in MPC1 and/or MPC2 levels were detected in the cardiac tissues of HFrEF patients, with ischemic or idiopatic origen, indicating a potential reduction in mitochondrial pyruvate uptake in the heart, which could be linked to unfavorable clinical features.

[Incidence and causes of hospitalization in patients with transthyretin (ATTR-CA) and light chain (AL-CA) cardiac amyloidosis]. / Incidencia y causas de hospitalización en pacientes con amiloidosis cardiaca por transtiretina (AC-ATTR) y por cadenas ligeras (AC-AL).

INTRODUCTION AND OBJETIVES: Cardiac amyloidosis (CA) is a disorder associated with high number of hospital admissions. Given the scarce information available, we propose an analysis of the incidence and causes of hospitalization in this disease. MATERIAL AND METHODS: One hundred and forty-three patients [128 by transthyretin (ATTR-CA) and 15 by light chains (AL-CA)] included in Registro de Amiloidosis Cardiaca de Galicia (AMIGAL) were evaluated, including all hospitalizations. RESULTS: During a median follow-up of 959 days there were 179 unscheduled hospitalizations [incidence rate (IR) 512.6 admissions per 1000 patients-year], most common due to cardiovascular reasons (n=109, IR 312.2). Most frequent individual cause of hospitalization was heart failure (n=87, TI 249.2). AL-CA was associated with a higher IR of unscheduled hospitalizations than ATTR-CA (IR 781 vs. 483.2; HR 1.62; p=0,029) due to non-cardiovascular admissions (IR 376 vs. 181.2; HR 2.07; p=0.027). Unscheduled admission-free survival at 1 and 3 years in AL-CA was inferior than in ATTR-CA (46.7% and 20.0% vs. 73.4% and 35.2%, respectively; p=0.021). CONCLUSIONS: CA was associated with high incidence of hospitalizations, being heart failure the most frequent individual cause; unscheduled admission-free survival in AL-CA was lower than in ATTR-CA due mostly to non-cardiovascular admissions.

Non-invasive electromechanical assessment during atrial fibrillation identifies underlying atrial myopathy alterations with early prognostic value.

Electromechanical characterization during atrial fibrillation (AF) remains a significant gap in the understanding of AF-related atrial myopathy. This study reports mechanistic insights into the electromechanical remodeling process associated with AF progression and further demonstrates its prognostic value in the clinic. In pigs, sequential electromechanical assessment during AF progression shows a progressive decrease in mechanical activity and early dissociation from its electrical counterpart. Atrial tissue samples from animals with AF reveal an abnormal increase in cardiomyocytes death and alterations in calcium handling proteins. High-throughput quantitative proteomics and immunoblotting analyses at different stages of AF progression identify downregulation of contractile proteins and progressive increase in atrial fibrosis. Moreover, advanced optical mapping techniques, applied to whole heart preparations during AF, demonstrate that AF-related remodeling decreases the frequency threshold for dissociation between transmembrane voltage signals and intracellular calcium transients compared to healthy controls. Single cell simulations of human atrial cardiomyocytes also confirm the experimental results. In patients, non-invasive assessment of the atrial electromechanical relationship further demonstrate that atrial electromechanical dissociation is an early prognostic indicator for acute and long-term rhythm control.

Impact of a pulmonary embolism response team initiative on hospital mortality of patients with bilateral pulmonary embolism.

INTRODUCTION: Pulmonary embolism (PE) response teams (PERT) for the management of high-risk PE (HR-PE) and intermediate-high risk PE (IHR-PE) are encouraged in PE guidelines. We aimed to assess the impact of a PERT initiative on mortality in these groups of patients, compared with standard care. METHODS: We conducted a prospective, single-center registry, including consecutive patients with HR-PE and IHR-PE with PERT activation from February-2018 to December-2020 (PERT group, n=78 patients) and compared it with an historic cohort of patients admitted to our hospital in a previous 2-year period (2014-2016), managed with standard of care (SC-group, n=108 patients). RESULTS: Patients in the PERT group were younger and less comorbid. The risk profile at admission and the percentage of HR-PE was similar in both cohorts (13% in SC-group and 14% in PERT-group, p=0.82). Reperfusion therapy was more frequently indicated in PERT-group (24.4% vs 10.2%, p=0.01), with no differences in fibrinolysis treatment, while catheter-directed therapy (CDT) was more frequent in PERT group (16.7% vs 1.9%, p<0.001). Reperfusion and CDT were associated with lower in-hospital mortality (2.9% vs 15.1%, p=0.001 for reperfusion and 1.5% vs 16.5%, p=0.001 for CDT). The primary outcome, 12-month mortality, was lower in the PERT-group (9% vs 22.2%, p=0.02), There were no differences in 30-day readmissions. In multivariate analysis PERT activation was associated with lower mortality at 12 months (HR 0.25, 95% confidence interval 0.09-0.7, p=0.008). CONCLUSION: A PERT initiative in patients with HR-PE and IHR-PE was associated with a significant reduction in 12-month mortality compared with standard of care, and also with an increase in the use of reperfusion, especially catheter-directed therapies.

Soluble HLA-G levels in heart transplant recipients: Dynamics and correlation with clinical outcomes.

PURPOSE: To describe the evolution of the serum levels of soluble HLA-G (s-HLA-G) during the first 12 months after heart transplantation (HT) and to correlate it with clinical outcomes. METHODS: Observational study based in a single-center cohort of 59 patients who underwent HT between December-2003 and March-2010. Soluble HLA-G levels were measured from serum samples extracted before HT, and 1, 3, 6 and 12 months after HT. The cumulative burden of s-HLA-G expression during the first post-transplant year was assessed by means of the area under the curve (AUC) of s-HLA-G levels over time and correlated with the acute rejection burden -as assessed by a rejection score-, the presence of coronary allograft vasculopathy (CAV) grade ≥ 1 and infections during the first post-transplant year; as well as with long-term patient and graft survival. Mean follow-up was 12.4 years. RESULTS: Soluble HLA-G levels decreased over the first post-transplant year (p = 0.020). The AUC of s-HLA-G levels during the first post-transplant year was higher among patients with infections vs. those without infections (p = 0.006). No association was found between the AUC of s-HLA-G levels and the burden of acute rejection or the development of CAV. Overall long-term survival, long-term survival free of late graft failure and cancer-free survival were not significantly different in patients with an AUC of s-HLA-G levels higher or lower than the median of the study population. CONCLUSIONS: Soluble HLA-G levels decreased over the first year after HT. Higher HLA-G expression was associated with a higher frequency of infections, but not with the burden of acute rejection or the development of CAV, neither with long-term patient or graft survival.

Cancer in patients with heart failure: Incidence, risk factors and prognostic impact.

AIMS: To assess the incidence of cancer diagnosis and cancer-related mortality in patients with heart failure (HF). METHODS: Observational study based in a prospective cohort of patients with HF referred to a specialized Spanish clinic between 2010 and 2019. The observed incidence of malignancies (excluding non-melanoma skin cancer) was compared to that expected for the general Spanish population according to the Global Cancer Observatory. RESULTS: We studied 1909 consecutive patients with HF. Over a median follow-up of 4.07 years, 165 new cases of malignancy were diagnosed. Observed age-standardized incidence rates of cancer were 861 (95% CI 618.4-2159.4) cases per 100,000 patients-years in men and 728.5 (95% CI 451.1-4308.7) cases per 100,000 patients-years in women; while age-standardized incidence rates of cancer expected for the general Spanish population were 479.4 cases per 100,000 patients-years in men (risk ratio = 1.80) and 295.5 cases per 100,000 patients-years in women (risk ratio = 2.46). Both a history of pre-existing malignancy at baseline and the development of new malignancies during follow-up were associated with reduced survival. Observed age-standardized cancer-related mortality was 344.1 (95% CI 202.1-1675) deaths per 100,000 patient-years in men and 217.0 (95% CI 32.8-3949.3) deaths per 100,000 patient-years in women; while age-standardized cancer-related mortality expected for the general Spanish population was 201.4 deaths per 100,000 patients-years in men (risk ratio = 1.71) and 96.2 deaths per 100,000 patients-years in women (risk ratio = 2.26). CONCLUSION: Patients with HF showed higher incidence rates of cancer diagnosis and cancer-related mortality than those expected for the general population.

Time-efficient three-dimensional transmural scar assessment provides relevant substrate characterization for ventricular tachycardia features and long-term recurrences in ischemic cardiomyopathy.

Delayed gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) imaging requires novel and time-efficient approaches to characterize the myocardial substrate associated with ventricular arrhythmia in patients with ischemic cardiomyopathy. Using a translational approach in pigs and patients with established myocardial infarction, we tested and validated a novel 3D methodology to assess ventricular scar using custom transmural criteria and a semiautomatic approach to obtain transmural scar maps in ventricular models reconstructed from both 3D-acquired and 3D-upsampled-2D-acquired LGE-CMR images. The results showed that 3D-upsampled models from 2D LGE-CMR images provided a time-efficient alternative to 3D-acquired sequences to assess the myocardial substrate associated with ischemic cardiomyopathy. Scar assessment from 2D-LGE-CMR sequences using 3D-upsampled models was superior to conventional 2D assessment to identify scar sizes associated with the cycle length of spontaneous ventricular tachycardia episodes and long-term ventricular tachycardia recurrences after catheter ablation. This novel methodology may represent an efficient approach in clinical practice after manual or automatic segmentation of myocardial borders in a small number of conventional 2D LGE-CMR slices and automatic scar detection.

The SADDEN DEATH Study: Results from a Pilot Study in Non-ICU COVID-19 Spanish Patients.

Introduction: The worldwide pandemic, coronavirus disease 2019 (COVID-19) is a novel infection with serious clinical manifestations, including death. Our aim is to describe the first non-ICU Spanish deceased series with COVID-19, comparing specifically between unexpected and expected deaths. Methods: In this single-centre study, all deceased inpatients with laboratory-confirmed COVID-19 who had died from March 4 to April 16, 2020 were consecutively included. Demographic, clinical, treatment, and laboratory data, were analyzed and compared between groups. Factors associated with unexpected death were identified by multivariable logistic regression methods. Results: In total, 324 deceased patients were included. Median age was 82 years (IQR 76-87); 55.9% males. The most common cardiovascular risk factors were hypertension (78.4%), hyperlipidemia (57.7%), and diabetes (34.3%). Other common comorbidities were chronic kidney disease (40.1%), chronic pulmonary disease (30.3%), active cancer (13%), and immunosuppression (13%). The Confusion, BUN, Respiratory Rate, Systolic BP and age ≥65 (CURB-65) score at admission was >2 in 40.7% of patients. During hospitalization, 77.8% of patients received antivirals, 43.3% systemic corticosteroids, and 22.2% full anticoagulation. The rate of bacterial co-infection was 5.5%, and 105 (32.4%) patients had an increased level of troponin I. The median time from initiation of therapy to death was 5 days (IQR 3.0-8.0). In 45 patients (13.9%), the death was exclusively attributed to COVID-19, and in 254 patients (78.4%), both COVID-19 and the clinical status before admission contributed to death. Progressive respiratory failure was the most frequent cause of death (92.0%). Twenty-five patients (7.7%) had an unexpected death. Factors independently associated with unexpected death were male sex, chronic kidney disease, insulin-treated diabetes, and functional independence. Conclusions: This case series provides in-depth characterization of hospitalized non-ICU COVID-19 patients who died in Madrid. Male sex, insulin-treated diabetes, chronic kidney disease, and independency for activities of daily living are predictors of unexpected death.

IgG4-aortitis among thoracic aortic aneurysms.

OBJECTIVE: The incidence of aortitis in patients with thoracic aortic diseases is not well established. The aim of this study was to analyse the frequency and clinical course of patients with aortitis in a surgical series. METHODS: 320 consecutive patients with ascending aorta/aortic arch aneurysm or acute aortic syndrome who underwent surgery from 2012 to 2017 in a single tertiary referral hospital were retrospectively reviewed. Epidemiological data, clinical course and variables related to diagnosis, treatment and follow-up were collected from patients with histologically proven aortitis. RESULTS: From 320 examined aortic samples, 279 (87.2%) thoracic aneurysms and 41 acute aortic syndromes (12.8%), 9 (2.8%) were aortitis: 3 cases of Takayasu's arteritis, 3 of IgG4-related aortitis, 2 of giant cell, and 1 classified as idiopathic. Median age at surgery was 53.4 (51-69.2) years and six cases were female. Seven patients presented with non-specific symptoms and the diagnosis was made at pathology. Surgery was elective in eight patients and emergent in one case of IgG4-related aortitis. 18F-fluorodeoxyglucose positron emission tomography/CT (18F-FDG PET/CT) was performed for disease extension study and as a monitoring technique during the follow-up of five patients, with just one case performed presurgically. All the patients with IgG4-related disease showed extrathoracic aortic involvement. There were no deaths, neither in-hospital nor during the 1.7 years of median follow-up. CONCLUSIONS: In surgically treated thoracic aorta pathology, the frequency of aortitis is low; IgG4-related disease is among the most common aetiologies with a frequency similar to other types of aortitis, such as Takayasu's and giant cell arteritis, and clinical manifestations are non-specific making presurgical diagnosis difficult. 18F-FDG PET/CT allows a better assessment of disease extension and therapeutic response. Surgery can be successfully performed and corticosteroid therapy ensures a good mid-term follow-up.

Implications of bipolar voltage mapping and magnetic resonance imaging resolution in biventricular scar characterization after myocardial infarction.

AIMS: We aimed to study the differences in biventricular scar characterization using bipolar voltage mapping compared with state-of-the-art in vivo delayed gadolinium-enhanced cardiac magnetic resonance (LGE-CMR) imaging and ex vivo T1 mapping. METHODS AND RESULTS: Ten pigs with established myocardial infarction (MI) underwent in vivo scar characterization using LGE-CMR imaging and high-density voltage mapping of both ventricles using a 3.5-mm tip catheter. Ex vivo post-contrast T1 mapping provided a high-resolution reference. Voltage maps were registered onto the left and right ventricular (LV and RV) endocardium, and epicardium of CMR-based geometries to compare voltage-derived scars with surface-projected 3D scars. Voltage-derived scar tissue of the LV endocardium and the epicardium resembled surface projections of 3D in vivo and ex vivo CMR-derived scars using 1-mm of surface projection distance. The thinner wall of the RV was especially sensitive to lower resolution in vivo LGE-CMR images, in which differences between normalized low bipolar voltage areas and CMR-derived scar areas did not decrease below a median of 8.84% [interquartile range (IQR) (3.58, 12.70%)]. Overall, voltage-derived scars and surface scar projections from in vivo LGE-CMR sequences showed larger normalized scar areas than high-resolution ex vivo images [12.87% (4.59, 27.15%), 18.51% (11.25, 24.61%), and 9.30% (3.84, 19.59%), respectively], despite having used optimized surface projection distances. Importantly, 43.02% (36.54, 48.72%) of voltage-derived scar areas from the LV endocardium were classified as non-enhanced healthy myocardium using ex vivo CMR imaging. CONCLUSION: In vivo LGE-CMR sequences and high-density voltage mapping using a conventional linear catheter fail to provide accurate characterization of post-MI scar, limiting the specificity of voltage-based strategies and imaging-guided procedures.