Understanding Left Ventricular Assist Devices.

BACKGROUND/AIMS: Long-term mechanical assist devices are now commonly used in the treatment of severe heart failure to unload the failing ventricle, maintain sufficient end-organ perfusion and improve functional capacity. Depending on the assisted ventricles, 3 categories of long-term assist devices are available: left ventricular assist device (LVAD), biventricular assist device and total artificial heart. Improvements in technology, especially the advent of smaller, durable continuous flow pumps, have led to the use of LVADs in a much broader population of patients in the last 10 years. Both the number of patients living with LVADs and the life expectancy of these patients are increasing. Regarding this growing number of patients with LVAD, intensivists need to understand the physiology of the devices, their functioning, potential complications and their management. METHODS: We performed a narrative review of relevant medical literature regarding the physiology of patients with LVAD and management of common complications relevant to the critical care physicians. RESULTS: The most frequent complications occurring in the LVAD patients after the post-operative period are bleeding, driveline infections, thrombosis, device malfunction, right ventricular failure and arrhythmias. Bleeding is the most frequent adverse event in LVAD due to a combination of anticoagulation and acquired von Willebrand disease secondary to shear stress produced within the pump. Their management includes antiplatelet therapy arrest, reduction of the anticoagulation regimen and specific therapy if feasible. Infection is the second most common cause of death after cardiac failure in LVAD patients. All infections must be aggressively treated to avoid seeding the device. Device thrombosis can develop even when patients are adequately anticoagulated and taking antiplatelet therapy because the LVAD is responsible for a chronic hypercoagulable state. CONCLUSION: Management of these unique patients in the ICU is best accomplished with a multidisciplinary team that includes specialists in advanced heart failure, LVAD nurse coordinators and intensivists.

New estimate of valvuloarterial impedance in aortic valve stenosis: A cardiac magnetic resonance study.

PURPOSE: Valvuloarterial impedance (ZVA ), estimating left ventricle (LV) afterload, has been proposed in transthoracic echocardiography (TTE) as a predictor of mortality in aortic valve stenosis (AVS). However, its calculation differs from arterial characteristic impedance (ZC ). Our aim was to apply the concept of ZC calculation to estimate ZVA from MR with carotid tonometry and to evaluate these indices through their associations with symptoms, LV diastolic function and aortic stiffness. MATERIALS AND METHODS: In 40 patients with AVS (76 ± 13 years), ZVA-TI derived from velocity time integral and E/Ea were estimated by TTE. ZVA-INS , based on ZC formula, calculated as the instantaneous pressure gradient to peak flow ratio and aortic compliance were estimated by using MRI at 1.5 Tesla. RESULTS: Both ZVA estimates were higher in symptomatic than asymptomatic patients (707 ± 22 versus 579 ± 53 dyne.s/cm5 , P = 0.031 for ZVA-INS and 4.35 ± 0.16 versus 3.33 ± 0.38 mmHg.m2 /mL, P = 0.018 for ZVA-TI ). Although they were both associated with aortic compliance (r = -0.45; P = 0.006 for ZVA-INS and r = -0.43; P = 0.008 for ZVA-TI ) only ZVA-INS was associated with E/Ea (r = 0.50; P < 0.001). In multivariate analysis to identify determinants of E/Ea, a model including age, mean blood pressure, LV ejection fraction, LV mass, and aortic valve area was performed (R2 = 0.41; P < 0.01). When ZVA-INS was added to the model, its overall significance was higher R2 = 0.56 (P < 0.01) and ZVA-INS and LV mass were the only significant determinants. CONCLUSION: ZVA-INS was more strongly associated with diastolic dysfunction than usual parameters quantifying AVS severity. This new ZVA estimate could improve LV afterload evaluation. LEVEL OF EVIDENCE: 1 J. Magn. Reson. Imaging 2017;45:795-803.

Pathophysiology of dyspnoea in acute pulmonary embolism: A cross-sectional evaluation.

BACKGROUND AND OBJECTIVE: Dyspnoea in pulmonary embolism (PE) remains poorly characterized. Little is known about how to measure intensity or about the underlying mechanisms that may be related to ventilatory abnormalities, alveolar dead space ventilation or modulating factors such as psychological modulate. We hypothesized that dyspnoea would mainly be associated with pulmonary vascular obstruction and its pathophysiological consequences, while the sensory-affective domain of dyspnoea would be influenced by other factors. METHODS: We undertook a prospective study of 90 consecutive non-obese patients (mean ± SD age: 49 ± 16 years, 41 women) without cardiorespiratory disease. All patients were hospitalized with symptoms for <15 days and a confirmed PE (multi-detector computed tomography (MDCT) scan, n = 87 and high-probability ventilation/perfusion scan, n = 3). Patients underwent assessment of dyspnoea using the Borg score, modified Medical Research Council (mMRC) scale, assessment of psychological trait, state of anxiety and depression and chest pain via the Visual Analogical Scale at the time of maximum dyspnoea. Functional evaluations such as the quantitative ventilation-perfusion lung scan, echocardiography, alveolar dead space fraction and tidal ventilation measurements were completed within 48 h of admission. RESULTS: Multivariate analyses demonstrated that dyspnoea was mainly linked to pulmonary vascular obstruction and/or its consequences such as raised pulmonary arterial pressure and chest pain. The sensory-affective domain of dyspnoea showed additional determinants such as age, depression and breathing variability. CONCLUSION: Dyspnoea is mainly related to vascular consequences of PE such as increased pulmonary arterial pressure or chest pain. The sensory-affective domain of dyspnoea also correlates with age, depression and breathing variability.

Left atrial aging: a cardiac magnetic resonance feature-tracking study.

Importance of left atrial (LA) phasic function evaluation is increasingly recognized for its incremental value in terms of prognosis and risk stratification. LA phasic deformation in the pathway of normal aging has been characterized using echocardiographic speckle tracking. However, no data are available regarding age-related variations using feature-racking (FT) techniques from standard cine magnetic resonance imaging (MRI). We studied 94 healthy adults (41 ± 14 yr, 47 women), who underwent MRI and Doppler echocardiography on the same day for left ventricular (LV) diastolic function evaluation. From cine MRI, longitudinal strain and strain rate, radial motion fraction, and radial relative velocity, respectively, corresponding to the reservoir, conduit, and LA contraction phases, were measured using dedicated FT software. Longitudinal strain and radial motion fraction decreased gradually and significantly with aging for both reservoir (r > 0.31, P < 0.003) and conduit (r > 0.54, P < 0.001) phases, whereas they remained unchanged during the LA contraction phase. Subsequently, the LA contraction-to-reservoir ratio increased significantly with age (r > 0.44, P < 0.001). Longitudinal strain rate and radial relative velocity significantly decreased with age (reservoir: r = 0.39, P < 0.001, conduit: r > 0.54, P < 0.001), and these associations tended to be stronger in women than in men. Finally, associations of LA functional indexes with age were stronger in individuals with lower transmitral early-to-atrial maximal velocity ratio and mitral annulus maximal longitudinal velocity, as well as higher transmitral early maximal-to-mitral annulus maximal longitudinal velocity ratio, highlighting the LV-LA interplay. Age-related changes in LA phasic function indexes were quantified by cine MRI images using a FT technique and were significantly related to age and LV diastolic function.

Age-specific changes in left ventricular diastolic function: a velocity-encoded magnetic resonance imaging study.

OBJECTIVES: Our objectives were to assess the ability of phasecontrast MRI (PC-MRI) to detect sub-clinical age-related variations of left ventricular (LV) diastolic parameters and thus to provide age-related reference ranges currently available for echocardiography but not for MRI-PC, and to identify independent associates of such variations. METHODS: We studied 100 healthy volunteers (age = 42 ± 15years, 50 females) who had MRI with simultaneous blood pressure measurements. LV mass and volumes were assessed. Semiautomated analysis of PC-MRI data provided: 1) early transmitral (Ef) and atrial (Af) peak filling flow-rates (ml/s) and filling volume (FV), 2) deceleration time (DT), isovolumic relaxation time (IVRT), and 3) early myocardial longitudinal (E') peak velocity. RESULTS: MRI-PC diastolic parameters were reproducible as reflected by low coefficients of variations (ranged between 0.31 to 6.26 %). Peak myocardial velocity E' (r = -0.63, p < 0.0001) and flow-rate parameters were strongly and independently associated to age (Ef/Af:r = -0.63, DT:r = 0.46, IVRT:r = 0.44, Ef/FV:r = -0.55, Af/FV:r = 0.56, p < 0.0001). Furthermore, LV relaxation parameters (E', DT, IVRT), were independently associated to LV remodelling (LV mass/end-diastolic volume) and myocardial wall thickness (p < 0.01). CONCLUSIONS: PC-MRI age-related reference ranges of diastolic parameters are provided. Such parameters might be useful for a fast, reproducible and reliable characterization of diastolic function in patients referred for clinical MRI exam KEY POINTS: • MRI age-related reference values of left ventricular diastolic parameters are provided. • MRI diastolic parameters can characterise sub-clinical age-related variations in healthy individuals. • Diastolic function would complement cardiac MRI exam with currently neglected data. • Diastolic function would enhance MRI diagnostic value in cardiomyopathy and heartfailure.

Impact of inodilator drugs on echocardiographic assessments of left ventricular filling pressure in patients with decompensated end-stage heart failure*.

OBJECTIVES: We investigated the impact of inodilators on the accuracy of E/e' ratio as a surrogate for pulmonary artery occlusion pressure in patients with decompensated end-stage systolic heart failure. SETTING: The ratio of early diastolic transmitral flow velocity to tissue Doppler mitral annular early diastolic velocity, E/e', and pulmonary artery occlusion pressure have been shown to be correlated. The validity of E/e' for predicting pulmonary artery occlusion pressure in patients with decompensated end-stage systolic heart failure was recently challenged, but the influence of inodilators was not taken into account, despite the reported influence of these drugs on left ventricular relaxation properties. PATIENTS AND INTERVENTION: Invasive hemodynamic monitoring and echocardiographic data were collected prospectively from 39 patients with decompensated end-stage systolic heart failure (92% male), aged 56 ± 13 years. These patients had dilated ventricles with a low cardiac index (1.9 ± 0.6 L/min/m) and high pulmonary artery occlusion pressure (22 ± 8 mm Hg), and 90% required inodilator support during hospitalization. MEASUREMENTS AND MAIN RESULTS: The correlation between septal E/e' and pulmonary artery occlusion pressure was good for examinations in the absence of inodilators (n = 21) (r = 0.7; p < 0.001), but no correlation was found when inodilators were used (n = 31). Lateral and mean E/e' were poorly correlated with pulmonary artery occlusion pressure, if at all, in both cases. CONCLUSIONS: By modifying ventricular relaxation properties and the influence of filling pressure on e', inodilator agents severely impair the correlation between E/e' and pulmonary artery occlusion pressure in patients with decompensated end-stage systolic heart failure.

The Clinical Impact and Good Practices of Remote Patient Monitoring for Chronic Heart Failure: A French Case Report.

Purpose: Remote patient monitoring (RPM) can improve the management of chronic diseases. Since 2019, RPM in chronic heart failure (CHF) management has been internationally supported. However, evidence on the clinical impact and good practices of RPM is scarce. We present a case of a patient with CHF that used RPM in France. Patients and Methods: A 74-year-old male was diagnosed with CHF (NYHA I) at the AP-HP Cochin Hospital in January 2020. He faced repetitive hospitalizations for acute heart failure and acute kidney injury. The causes of these acute episodes were unknown. Three therapeutic interventions were implemented (diuretic treatment, RPM and therapeutic education sessions). The patient answered questionnaires regularly and directly through the RPM web application named Satelia®Cardio. Therapeutic education was provided to instruct the patient about his symptoms and treatment management. Results: Since November 11, 2020, the patient had seven hospitalizations representing a total length of stay of 76 days over a period of 15 months and 2 weeks. Pericarditis was diagnosed as a potential cause and a pre-operative checkup was performed. No tangible benefits were found with diuretic treatment and therapeutic education since they had no effect on stopping the acute episodes leading to hospitalization. RPM did not trigger any clinical alerts until his last hospitalization. During this stay, a clinical telehealth nurse reviewed the patient's clinical setup and found that his initial baseline weight was incorrectly inputted. Since amending this, there were no new episodes. A high-risk, complex and costly heart surgery for pericardial decortication was avoided, and patient satisfaction has increased. Conclusion: To respect good practices, inclusion not only involves adding or registering a patient to a telehealth activity and database but involves redesigning the management and pathway of patients in order to conduct periodic and personalized clinical care via integrated technology into routine care.

Right ventricular diastolic function in aging: a head-to-head comparison between phase-contrast MRI and Doppler echocardiography.

To evaluate right ventricle (RV) diastolic function from phase-contrast MRI (PC-MRI) in aging. 89 healthy individuals (50 men, 43 ± 15 years) underwent cardiac MRI including 2D PC-MRI (1.5T) and reference Doppler echocardiography of both ventricles on the same day. Conventional echocardiographic parameters were estimated: early (E, cm/s) and atrial (A) peak velocities as well as myocardial early peak longitudinal velocity (E'). PC-MRI images were analyzed using custom software, providing: E', E and A waves along with respective peak flow rates (Ef, Af, mL/s) and filling volume (mL), for both ventricles. Intra- and inter-observer reproducibility was studied in 30 subjects and coefficients of variation (CoV) as well as intra-class correlation coefficients (ICC) were provided. RV diastolic function indices derived from PC-MRI data were reproducible (CoV ≤ 21%, ICC ≥ 0.75) and reliable as reflected by significant associations with left ventricular diastolic function indices assessed using both echocardiography (linear regression Pearson correlation coefficient r ≤ 0.59) and PC-MRI (r ≤ 71). Despite the fair associations between RV echocardiography and PC-MRI (r ≤ 0.25), the highest correlation with age was obtained for MRI Ef/Af ratio (r = - 0.64, p < 0.0001 vs. r = - 0.40, p = 0.0001 for echocardiographic E/A). Among PC-MRI E/A ratios, highest correlations with age were observed for flow rate and mean velocity ratios (r = - 0.61, p < 0.0001) as compared to maximal velocity ratios (r = - 0.56, p < 0.0001). Associations with age for E' were equivalent between PC-MRI (mean velocity: r = - 0.40, p < 0.0001; maximal velocity: r = - 0.36, p = 0.0005) and echocardiography (r = - 0.36, p = 0.0006). Finally, the significant and age-independent associations between RV mass/end-diastolic volume and E' were stronger for PC-MRI (mean velocity: r = - 0.36, p = 0.0006; maximal velocity: r = - 0.28, p = 0.007) than echocardiography (r = - 0.09, p = 0.38). PC-MRI tricuspid inflow and annulus myocardial velocity parameters were reproducible and able to characterize age-related variations in RV diastolic function.

Automated left ventricular diastolic function evaluation from phase-contrast cardiovascular magnetic resonance and comparison with Doppler echocardiography.

BACKGROUND: Early detection of diastolic dysfunction is crucial for patients with incipient heart failure. Although this evaluation could be performed from phase-contrast (PC) cardiovascular magnetic resonance (CMR) data, its usefulness in clinical routine is not yet established, mainly because the interpretation of such data remains mostly based on manual post-processing. Accordingly, our goal was to develop a robust process to automatically estimate velocity and flow rate-related diastolic parameters from PC-CMR data and to test the consistency of these parameters against echocardiography as well as their ability to characterize left ventricular (LV) diastolic dysfunction. RESULTS: We studied 35 controls and 18 patients with severe aortic valve stenosis and preserved LV ejection fraction who had PC-CMR and Doppler echocardiography exams on the same day. PC-CMR mitral flow and myocardial velocity data were analyzed using custom software for semi-automated extraction of diastolic parameters. Inter-operator reproducibility of flow pattern segmentation and functional parameters was assessed on a sub-group of 30 subjects. The mean percentage of overlap between the transmitral flow segmentations performed by two independent operators was 99.7 ± 1.6%, resulting in a small variability (<1.96 ± 2.95%) in functional parameter measurement. For maximal myocardial longitudinal velocities, the inter-operator variability was 4.25 ± 5.89%. The MR diastolic parameters varied significantly in patients as opposed to controls (p < 0.0002). Both velocity and flow rate diastolic parameters were consistent with echocardiographic values (r > 0.71) and receiver operating characteristic (ROC) analysis revealed their ability to separate patients from controls, with sensitivity > 0.80, specificity > 0.80 and accuracy > 0.85. Slight superiority in terms of correlation with echocardiography (r = 0.81) and accuracy to detect LV abnormalities (sensitivity > 0.83, specificity > 0.91 and accuracy > 0.89) was found for the PC-CMR flow-rate related parameters. CONCLUSIONS: A fast and reproducible technique for flow and myocardial PC-CMR data analysis was successfully used on controls and patients to extract consistent velocity-related diastolic parameters, as well as flow rate-related parameters. This technique provides a valuable addition to established CMR tools in the evaluation and the management of patients with diastolic dysfunction.

Cardiac sarcoidosis.

Cardiac involvement is undeniably one of the most challenging issues in sarcoidosis. Although autopsy studies reveal heart lesions in 20 to 30% of sarcoid patients, fewer than 5% suffer from clinical disease. Cardiac sarcoidosis (CS) has a predilection for the myocardium, but the pericardium and endocardium may also be affected. CS manifestations are various and most frequently include the following: (1) aberrations of atrioventricular or intraventricular conduction, either silent or symptomatic; (2) ventricular arrhythmias; (3) subacute congestive heart failure; and (4) sudden death. CS must be detected in all sarcoid patients by means of detailed medical history, physical examination, and resting electrocardiogram (ECG) at first evaluation and during follow-up. In patients with suspected CS, further investigations are aimed at evaluating diagnosis and cardiac consequences. Unfortunately, no gold standard exists that would allow CS diagnosis with a level of confidence. Endomyocardial biopsy is an invasive procedure that lacks sensitivity. Patients need, at a minimum, specialized cardiologic advice, echocardiography, and 24-hour ambulatory ECG. Other diagnostic tools include thallium, technetium, and gallium scintigraphy, and more recently, 18F-fluorodeoxyglucose positron emission tomography and cardiac magnetic resonance (CMR). The respective role of these new imaging tools in the diagnostic approach remains to be defined. CMR has the advantage of not exposing patients to radiation, but it is not feasible in those with cardiac devices. In Western countries, heart involvement accounts for 13 to 25% of sarcoidosis-related deaths, and it is the leading cause of mortality in Japan. The main prognostic indicators are New York Heart Association functional class, left ventricular enlargement, and sustained ventricular tachycardia. Treatment is based on systemic corticosteroids with an initial dose between 30 mg/day and 1 mg/kg/day (which is usually maintained for at least 24 months), specific cardiologic agents, and the placement of a pacemaker or implantable cardiac defibrillator in case of an atrioventricular block or severe intractable ventricular arrhythmias. Cardiac transplantation is exceptionally required.

Case of indolent endocarditis due to Pseudomonas stutzeri with genetic evidence of relapse after 4 years.

Pseudomonas stutzeri, a gram-negative bacterium, is a common inhabitant of soil and water. We report an unusual case of a relapse of infective endocarditis due to P. stutzeri 4 years after the initial episode. The identity of the strains was proven by genomic analysis.

First case of Streptococcus oligofermentans endocarditis determined based on sodA gene sequences after amplification directly from valvular samples.

We report the first case of infection due to Streptococcus oligofermentans, which is a recently described oral Streptococcus species. It was responsible for the endocarditis and left forearm abscess of a 43-year-old woman. Identification was made using molecular techniques performed directly from valvular and surgical samples.

Coronary microcirculation in acute myocardial ischaemia: From non-invasive to invasive absolute flow assessment.

Although substantial progress has been made in recent decades in reducing mortality and performing optimal revascularization in patients with myocardial infarction, ischaemic heart disease, including acute coronary syndrome, remains the leading cause of mortality worldwide. One of the remaining challenges is to better detect, prevent and treat extended myocardial damage despite angiographically optimal revascularization. Several indices are available in clinical practice to evaluate myocardial damage, infarct size and potential myocardial recovery. These indices are divided into two categories: non-invasive, generally performed after revascularization; and invasive, performed during the revascularization procedure. They allow the clinician to detect patients at risk and may help us to tailor the medical therapy and discharge strategy according to myocardial damage. Because of the number of indices, it is difficult to properly evaluate new therapeutics or to adopt one index that will provide sufficient data to better evaluate and understand the part of the coronary vasculature that is not seen - the microcirculation or so-called "black box". The aim of this review is to describe the non-invasive and invasive indices used to describe the microcirculation and their ability to predict clinical impact, and current dedicated therapeutics that may help to reduce microvascular damage and improve clinical outcomes.

Scan-rescan reproducibility of ventricular and atrial MRI feature tracking strain.

BACKGROUND: A feature tracking (FT) was designed to simultaneously extract myocardial strains in main cardiac chambers from cine MRI images. Its inter-observer and scan-rescan reproducibility was assessed and sample sizes required to detect predefined longitudinal changes in strain values were provided. METHOD: FT was applied on left (LV) and right (RV) ventricles as well as left atrium (LA) of 21 individuals (66 ± 10 years) who underwent 2 MRIs 2 weeks apart. Global peaks for radial, circumferential, longitudinal strains, radial motion fraction (Mr), fractional area change (FAC) and tricuspid annular plane excursion (TAPSE) were estimated. Inter-operator and inter-exam reproducibility were evaluated using coefficients of variations (CV) and intra-class correlation coefficients (ICC). RESULTS: Reproducibility of all measurements were good to excellent for inter-operator (LV:CV<6.5%, ICC>0.91; RV:CV<12%, ICC>0.86; LA:CV<14%, ICC>0.85) and inter-study (LV:CV<15%, ICC>0.65; RV:CV<20%, ICC>0.71; LA:CV<20.5%, ICC>0.83) evaluations. Reasonable sample sizes are required to detect a longitudinal difference of 10-15% in strain values (LV:5 to 33 individuals, RV:14 to 62 individuals, LA:4 to 65 individuals). CONCLUSIONS: FT-based functional evaluation of main heart chamber deformation from cine MRI is repeatable and thus suitable for follow-up. Strain measurements may help for the joint clinical evaluation of LV, RV or LA implication in various cardiomyopathies.

Management of end-stage heart failure patients with or without ventricular assist device: an observational comparison of clinical and economic outcomes.

OBJECTIVES: Heart transplantation (HT) and ventricular assist devices (VAD) for the management of end-stage heart failure have not been directly compared. We compare the outcomes and use of resources with these 2 strategies in 2 European countries with different allocation systems. METHODS: We studied 83 patients managed by VAD as the first option in Bad Oeynhausen, Germany (Group I) and 141 managed with either HT or medical therapy, as the first option, in Paris, France (Group II). The primary end-point was 2-year survival. Kaplan-Meier analyses were performed after the application of propensity score weights to mitigate the effects of non-random group assignment. The secondary end-points were resource utilization and costs. Subgroup analyses were performed for patients undergoing HT and patients treated with inotropes at the enrolment time. RESULTS: The Group I patients were more severely ill and haemodynamically compromised, and 28% subsequently underwent HT vs 55% primary HT in Group II, P < 0.001. The adjusted probability of survival was 44% in Group I vs 70% in Group II, P <0.0001. The mean cumulated 2-year costs were €281 361 ± 156 223 in Group I and €47 638 ± 35 061 in Group II, P < 0.0001. Among patients who underwent HT, the adjusted probability of survival in Group I (n = 23) versus Group II (n = 78) was 76% versus 68%, respectively (0.09), though it differed in the inotrope-treated subgroups (77% in Group I vs 67% in Group II, P = 0.04). CONCLUSIONS: HT should remain the first option for end-stage heart failure patients, associated with improved outcomes and better cost-effectiveness profile. VAD devices represent an option when transplant is not possible or when patient presentation is not optimal.

Head-to-head comparison of the diagnostic performance of coronary computed tomography angiography and dobutamine-stress echocardiography in the evaluation of acute chest pain with normal ECG findings and negative troponin tests: A prospective multicenter study.

OBJECTIVE: To perform a head-to-head comparison of coronary CT angiography (CCTA) and dobutamine-stress echocardiography (DSE) in patients presenting recent chest pain when troponin and ECG are negative. METHODS: Two hundred seventeen patients with recent chest pain, normal ECG findings, and negative troponin were prospectively included in this multicenter study and were scheduled for CCTA and DSE. Invasive coronary angiography (ICA), was performed in patients when either DSE or CCTA was considered positive or when both were non-contributive or in case of recurrent chest pain during 6month follow-up. The presence of coronary artery stenosis was defined as a luminal obstruction >50% diameter in any coronary segment at ICA. RESULTS: ICA was performed in 75 (34.6%) patients. Coronary artery stenosis was identified in 37 (17%) patients. For CCTA, the sensitivity was 96.9% (95% CI 83.4-99.9), specificity 48.3% (29.4-67.5), positive likelihood ratio 2.06 (95% CI 1.36-3.11), and negative likelihood ratio 0.07 (95% CI 0.01-0.52). The sensitivity of DSE was 51.6% (95% CI 33.1-69.9), specificity 46.7% (28.3-65.7), positive likelihood ratio 1.03 (95% CI 0.62-1.72), and negative likelihood ratio 1.10 (95% CI 0.63-1.93). The CCTA: DSE ratio of true-positive and false-positive rates was 1.70 (95% CI 1.65-1.75) and 1.00 (95% CI 0.91-1.09), respectively, when non-contributive CCTA and DSE were both considered positive. Only one missed acute coronary syndrome was observed at six months. CONCLUSIONS: CCTA has higher diagnostic performance than DSE in the evaluation of patients with recent chest pain, normal ECG findings, and negative troponine to exclude coronary artery disease.

Gated blood pool tomoscintigraphy with 4-dimensional optical flow motion analysis quantifies left ventricular mechanical activation and synchronization.

BACKGROUND: Gated blood pool tomoscintigraphy has the unique capacity to accurately assess myocardial motion in paced patients. Our goal was to develop a precise radionuclide angiography analysis of cardiac dynamics to evaluate ventricular synchronization in patients undergoing biventricular pacing. METHODS AND RESULTS: On the basis of a 4-dimensional deformable motion estimation algorithm, we developed a protocol allowing estimation of motion fields after gated blood pool tomoscintigraphy. We measured the mechanical activation times for 17 left ventricular (LV) segments and determined the main types of contraction pattern in 10 normal subjects, 17 patients with dilated cardiomyopathy, and 12 resynchronized patients. We analyzed intra-LV dyssynchrony: apex to base, septum to lateral wall, and anterior wall to inferior wall. Three-dimensional measurements of intra-LV activation time (r > .80, P < .001) and LV ejection fraction (r > 0.90, P < .0001) are linearly correlated to 2-dimensional values. LV contraction follows the electrical activation pattern. In normal subjects the anteroseptal and anterior segments are first activated, followed by the apex and inferolateral segments. In resynchronized patients contraction begins with the lateral and apicoseptal segments in correspondence to the LV and right ventricular lead implantation. CONCLUSIONS: By measuring mechanical activation times, this technique allows for the analysis of the regional synchronous contraction. This may help to assess the variation of the activation pattern according to the cardiomyopathy type and the role of septal resynchronization in ventricular functional recovery.

Optimization of factor analysis of the left ventricle in echocardiography for detecting wall motion abnormalities.

This study has tested solutions to optimize the ability of factor analysis of the left ventricle in echocardiography (FALVE) to detect segmental wall motion abnormalities automatically. On four- and two-chamber views of 38 patients, two factors (one flat curve and one curve describing the contraction-relaxation sequence) were extracted and associated factor images were combined to synthesize a parametric image (constant image in green, positive/negative values of the contraction-relaxation image in red/blue). The segments were graded on the visual and the parametric views. The impact of selecting a whole cardiac cycle, masking the left ventricle and realigning the image sequence on the results, was demonstrated. Systematic realignment had a positive impact, especially for patients with left bundle branch block or pacemaker. After alignment, for the entire population, the absolute concordance was 68.6% and the relative concordance (within one grade) was 99%. Thus, FALVE is promising for detecting segmental wall motion abnormalities.

Assessment of right ventricular dysfunction predictors before the implantation of a left ventricular assist device in end-stage heart failure patients using echocardiographic measures (ARVADE): Combination of left and right ventricular echocardiographic variables.

BACKGROUND: Right ventricular failure (RVF) is a major cause of morbidity and mortality in left ventricular assist device (LVAD) recipients. OBJECTIVES: To identify preoperative echocardiographic predictors of post-LVAD RVF. METHODS: Data were collected for 42 patients undergoing LVAD implantation in Germany. RVF was defined as the need for placement of a temporary right ventricular assist device or the use of inotropic agents for 14 days. Data for RVF patients were compared with those for patients without RVF. A score (ARVADE) was established with independent predictors of RVF by rounding the exponentiated regression model coefficients to the nearest 0.5. RESULTS: RVF occurred in 24 of 42 LVAD patients. Univariate analysis identified the following measurements as RVF risk factors: basal right ventricular end-diastolic diameter (RVEDD), minimal inferior vena cava diameter, pulsed Doppler transmitral E wave (Em), Em/tissue Doppler lateral systolic velocity (SLAT) ratio and Em/tissue Doppler septal systolic velocity (SSEPT) ratio. Em/SLAT≥18.5 (relative risk [RR] 2.78, 95% confidence interval [CI] 1.38-5.60; P=0.001), RVEDD≥50 mm (RR 1.97, 95% CI 1.21-3.20; P=0.008) and INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) level 1 (RR 1.74, 95% CI 1.04-2.91; P=0.04) were independent predictors of RVF. An ARVADE score>3 predicted the occurrence of post-implantation RVF with a sensitivity of 89% and a specificity of 74%. CONCLUSION: The ARVADE score, combining one clinical variable and three echocardiographic measurements, is potentially useful for selecting patients for the implantation of an assist device.

Heart failure while on ventricular assist device support: a true clinical entity?

Ventricular assist devices (VADs) have become an established therapeutic option for patients with end-stage heart failure. The appearance of heart failure in VAD patients seems unexpected. Nevertheless, this phenomenon is not rare. We report six cases of VAD patients with clinical presentation of heart failure at different times after implantation and describe the mechanisms involved. The aetiology of this heart failure, like its clinical presentation, varies and has yet to be identified.