Outcome of Temporary Circulatory Support As a Bridge-to-Left Ventricular Assist Device Strategy in Cardiogenic Shock Patients.

OBJECTIVES: Temporary circulatory support (TCS) as a bridge-to-left ventricular assist device (BTL) in cardiogenic shock patients has been increasing, but limited data exists on this BTL strategy. We aimed at analyzing the outcome of BTL patients in a population of cardiogenic shock patients compared with those without TCS at the time of the left ventricular assist device (LVAD) surgery and identify predictors of postoperative mortality in this specific population. DESIGN: A multicenter retrospective observational study conducted in 19 centers from 2006 to 2016. SETTING: Nineteen French centers. PATIENTS: A total of 329 cardiogenic shock patients at the time of LVAD implantation were analyzed. Patients were divided in three groups: those under TCS at the time of LVAD implantation (n = 173), those with TCS removal before LVAD surgery (n = 24), and those who did not undergo a bridging strategy (n = 152). Primary endpoint was 30-day mortality. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among the BTL group, 68 (39.3%), 18 (10.4%), and 15 (8.7%) patients were under venoarterial extracorporeal membrane oxygenation, Impella, and IABP support alone, and 72 patients (20.6%) were under multiple TCS support. BTL patients presented similar 30 days survival compared with the TCS removal and non-BTL groups. However, BTL group had a significantly longer ICU duration stay, with two-fold duration of mechanical ventilation time, but the three groups experienced similar postoperative complications. Multivariate analysis identified three independent predictors of mortality in the BTL group: combined surgery with LVAD, body mass index (BMI), and heart failure (HF) duration. BTL strategy was not an independent predictor of mortality in cardiogenic shock patients who underwent LVAD. CONCLUSIONS: BTL strategy is not associated with a lower survival among cardiogenic shock patients with LVAD implantation. Predictors of mortality are combined surgery with LVAD, higher BMI, and HF duration.

Echocardiographic view and feature selection for the estimation of the response to CRT.

Cardiac resynchronization therapy (CRT) is an implant-based therapy applied to patients with a specific heart failure (HF) profile. The identification of patients that may benefit from CRT is a challenging task and the application of current guidelines still induce a non-responder rate of about 30%. Several studies have shown that the assessment of left ventricular (LV) mechanics by speckle tracking echocardiography can provide useful information for CRT patient selection. A comprehensive evaluation of LV mechanics is normally performed using three different echocardioraphic views: 4, 3 or 2-chamber views. The aim of this study is to estimate the relative importance of strain-based features extracted from these three views, for the estimation of CRT response. Several features were extracted from the longitudinal strain curves of 130 patients and different methods of feature selection (out-of-bag random forest, wrapping and filtering) have been applied. Results show that more than 50% of the 20 most important features are calculated from the 4-chamber view. Although features from the 2- and 3-chamber views are less represented in the most important features, some of the former have been identified to provide complementary information. A thorough analysis and interpretation of the most informative features is also provided, as a first step towards the construction of a machine-learning chain for an improved selection of CRT candidates.

Characterization of Responder Profiles for Cardiac Resynchronization Therapy through Unsupervised Clustering of Clinical and Strain Data.

BACKGROUND: The mechanisms of improvement of left ventricular (LV) function with cardiac resynchronization therapy (CRT) are not yet elucidated. The aim of this study was to characterize CRT responder profiles through clustering analysis, on the basis of clinical and echocardiographic preimplantation data, integrating automatic quantification of longitudinal strain signals. METHODS: This was a multicenter observational study of 250 patients with chronic heart failure evaluated before CRT device implantation and followed up to 4 years. Clinical, electrocardiographic, and echocardiographic data were collected. Regional longitudinal strain signals were also analyzed with custom-made algorithms in addition to existing approaches, including myocardial work indices. Response was defined as a decrease of ≥15% in LV end-systolic volume. Death and hospitalization for heart failure at 4 years were considered adverse events. Seventy features were analyzed using a clustering approach (k-means clustering). RESULTS: Five clusters were identified, with response rates between 50% in cluster 1 and 92.7% in cluster 5. These five clusters differed mainly by the characteristics of LV mechanics, evaluated using strain integrals. There was a significant difference in event-free survival at 4 years between cluster 1 and the other clusters. The quantitative analysis of strain curves, especially in the lateral wall, was more discriminative than apical rocking, septal flash, or myocardial work in most phenogroups. CONCLUSIONS: Five clusters are described, defining groups of below-average to excellent responders to CRT. These clusters demonstrate the complexity of LV mechanics and prediction of response to CRT. Automatic quantitative analysis of longitudinal strain curves appears to be a promising tool to improve the understanding of LV mechanics, patient characterization, and selection for CRT.

Prediction of response to cardiac resynchronization therapy using a multi-feature learning method.

We hypothesized that a multiparametric evaluation, based on the combination of electrocardiographic and echocardiographic parameters, could enhance the appraisal of the likelihood of reverse remodeling and prognosis of favorable clinical evolution to improve the response of cardiac resynchronization therapy (CRT). Three hundred and twenty-three heart failure patients were retrospectively included in this multicenter study. 221 patients (68%) were responders, defined by a decrease in left ventricle end-systolic volume ≥15% at the 6-month follow-up. In addition, strain data coming from echocardiography were analyzed with custom-made signal processing methods. Integrals of regional longitudinal strain signals from the beginning of the cardiac cycle to strain peak and to the instant of aortic valve closure were analyzed. QRS duration, septal flash and different other features manually extracted were also included in the analysis. The random forest (RF) method was applied to analyze the relative feature importance, to select the most significant features and to build an ensemble classifier with the objective of predicting response to CRT. The set of most significant features was composed of Septal Flash, E, E/A, E/EA, QRS, left ventricular end-diastolic volume and eight features extracted from strain curves. A Monte Carlo cross-validation method with 100 runs was applied, using, in each run, different random sets of 80% of patients for training and 20% for testing. Results show a mean area under the curve (AUC) of 0.809 with a standard deviation of 0.05. A multiparametric approach using a combination of echo-based parameters of left ventricular dyssynchrony and QRS duration helped to improve the prediction of the response to cardiac resynchronization therapy.

Prognostic Usefulness of Myocardial Work in Patients With Heart Failure and Reduced Ejection Fraction Treated by Sacubitril/Valsartan.

The noninvasive assessment of myocardial work (MW) by pressure-strain loops analysis (PSL) is a relative new tool for the evaluation of myocardial performance. Sacubitril/Valsartan is a treatment for heart failure with reduced ejection fraction (HFrEF) which has a spectacular effect on the reduction of cardiovascular events (major adverse cardiovascular events [MACEs]). This study aimed to evaluate the short- and medium-term effect of Sacubitril/Valsartan treatment on MW parameters and the prognostic value of MW in this specific group of patients. Seventy-nine patients with HFrEF (mean age: 66 ± 12 years; LV ejection fraction: 28% ± 9%) were prospectively included in the study and treated with Sacubitril/Valsartan. Echocardiographic examination was performed at baseline, and after 6- and 12-month of therapy with Sacubitril/Valsartan. Sacubitril/Valsartan significantly increased myocardial constructive work (CW) (1023 ± 449 vs 1424 ± 484 mm Hg%, p <0.0001) and myocardial work efficiency (WE) [87 (78to 90) vs 90 (86 to 95), p <0.0001]. During FU (2.6 ± 0.9 years), MACEs occurred in 13 (16%) patients. After correction for LV size, LV ejection fraction and WE, global myocardial constructive work (CW) was the only predictor of MACEs [hazard ratio [HR] 0.99 (0.99 to 1.00), p = 0.04]. A CW <910 mm Hg identified patients at particularly increase risk of MACEs [HR 11.09 (1.45 to 98.94), p = 0.002, log-rank test p <0.0001]. In conclusion, in patients with HFrEF who receive a comprehensive background beta-blocker and mineral-corticoid receptor antagonist therapy, Sacubitril/Valsartan induces a significant improvement of myocardial CW and WE. In this population, the estimation of CW before the initiation of Sacubitril/Valsartan allows the prediction of MACEs.

Heart failure with preserved ejection fraction: A clustering approach to a heterogenous syndrome.

BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome at the crossroads of multiple co-morbidities; there is no valid treatment for this condition. Defining new phenotypes could play a role in improving treatment and prognosis. AIM: To identify groups with different pathophysiologies by applying a clustering approach to a multicentric cohort of patients with HFpEF. METHODS: A total of 538 patients from the multicentre KaRen study were included. Accurate clinical, biological and ultrasound data are available, with a mean follow-up of 28 months. Based on a clustering analysis, the population was separated into groups based on 55 variables, comparing distribution of deaths and hospitalizations between groups. RESULTS: Three clusters were identified from 356 analysable patients (mean age 76.1±9.31 years; 43.5% men): cluster 1 (n=128) comprised overweight, relatively young men at high cardiovascular risk, in sinus rhythm, with altered renal function; cluster 2 (n=134) comprised women, most of whom had conserved left ventricular function; cluster 3 (n=94) had the highest incidence of mitral regurgitation, atrial remodelling and rhythm disorders. There were no significant differences, only a trend towards early mortality in cluster 3. CONCLUSIONS: Clustering analysis seems to be effective at individualizing subgroups with different physiopathologies in HFpEF. The clinical relevance of these phenotypes needs to be studied, and may concern treatment strategy more than prognostic differences.

EDUCATIONAL SERIES ON THE SPECIALIST VALVE CLINIC: The central role of the cardiac imager in heart valve disease

In this review, we discuss the central role of the imager in the heart team in the successful application of current guidelines for heart valve diseases to daily practice, and for improving patient care through new approaches, new techniques and new strategies for dealing with increasingly complex cases. This is an opportunity to emphasize the importance of having good imagers and the value of continuous learning in a modern heart team. It is essential to employ technological improvements and to appropriately adapt guidelines to the patients we see day to day.

One year prognostic value of B-lines in dyspnoeic patients.

AIMS: Studies have demonstrated the reliability of B-lines evaluated by lung ultrasonography to identify pulmonary congestion, but information is lacking about its utility as a prognostic marker of heart failure (HF). We sought to assess the prognostic midterm value of B-lines in ambulatory patients presenting with dyspnoea, as an additive tool for patient management and to avoid acute HF exacerbations. METHODS AND RESULTS: A total of 93 patients presenting with dyspnoea (New York Heart Association ≥2) were prospectively recruited in an outpatient clinic, and underwent clinical and echocardiographic evaluation, as well as B-line evaluation with lung ultrasonography in eight zones. Primary endpoint was HF hospitalization at 1 year. A total of 88 patients were included, age 72.3 ± 9.6, with left ventricular ejection 47.7 ± 28.6%; E/e' 16.9 ± 10.9, left atrial volume 51.9 ± 22.5 mL/m2 ; peak tricuspid regurgitation velocity 2.6 ± 0.5 m/s, average B-line count 7.7 ± 10. 8 (9%) patients were hospitalized for HF, seven of which had ≥6 B-lines. B-line cut-off ≥6 (specificity = 66.2%; sensitivity = 87.5%) was predictive for HF hospitalization, with an odds ratio at 13.7 for HF hospitalization at 1 year [IC95% (1.6-117.4), P = 0.017]. CONCLUSIONS: Ambulatory patients with ≥6 B-lines have a higher risk of HF hospitalization at 1 year. This study highlights the prognostic value of B-lines in evaluating HF risk in dyspnoeic patients.