In daily clinical practice, LV systolic function is routinely assessed with the use of two‐dimensional echocardiography. Using biplane LV end‐diastolic and end‐systolic volumes, LVEF is calculated. ...The introduction of real‐time three‐dimensional echocardiography has improved the accuracy of echocardiographic assessment of LVEF. However, calculated LVEF may not truly represent LV systolic function in specific cardiac diseases or when subtle LV dysfunction is present. Two‐dimensional speckle tracking echocardiography enables assessment of myocardial strain, thereby providing detailed information on global and regional LV deformation. This is of particular interest when subtle LV systolic dysfunction is present despite preserved LVEF. In this review, the potential use of LV global longitudinal strain to detect subtle LV systolic dysfunction is illustrated in various clinical scenarios.
Abstract Computed tomography (CT) plays an important role in the workup of patients who are candidates for implantation of a catheter-based aortic valve, a procedure referred to as transcatheter ...aortic valve implantation (TAVI) or transcatheter aortic valve replacement (TAVR). Contrast-enhanced CT imaging provides information on the suitability of the peripheral access vessels to accommodate the relatively large sheaths necessary to introduce the prosthesis. CT imaging also provides accurate dimensions of the ascending aorta, aortic root, and aortic annulus which are of importance for prosthesis sizing, and initial data indicate that compared with echocardiographic sizing, CT-based sizing of the prosthesis may lead to better results for postprocedural aortic valve regurgitation. Finally, CT permits one to predict appropriate fluoroscopic projections which are oriented orthogonal to the aortic valve plane. This consensus document provides recommendations about the use of CT imaging in patients scheduled for TAVR/TAVI, including data acquisition, interpretation, and reporting.
Ventricular–arterial coupling (VAC) plays a major role in the physiology of cardiac and aortic mechanics, as well as in the pathophysiology of cardiac disease. VAC assessment possesses independent ...diagnostic and prognostic value and may be used to refine riskstratification and monitor therapeutic interventions. Traditionally, VAC is assessed by the non‐invasive measurement of the ratio of arterial (Ea) to ventricular end‐systolic elastance (Ees). With disease progression, both Ea and Ees may become abnormal and the Ea/Ees ratio may approximate its normal values. Therefore, the measurement of each component of this ratio or of novel more sensitive markers of myocardial (e.g. global longitudinal strain) and arterial function (e.g. pulse wave velocity) may better characterize VAC. In valvular heart disease, systemic arterial compliance and valvulo–arterial impedance have an established diagnostic and prognostic value and may monitor the effects of valve replacement on vascular and cardiac function. Treatment guided to improve VAC through improvement of both or each one of its components may delay incidence of heart failure and possibly improve prognosis in heart failure. In this consensus document, we describe the pathophysiology, the methods of assessment as well as the clinical implications of VAC in cardiac diseases and heart failure. Finally, we focus on interventions that may improve VAC and thus modify prognosis.
Approximately 4% of subjects aged 75 years or more have clinically relevant tricuspid regurgitation (TR). Primary TR results from anatomical abnormality of the tricuspid valve apparatus and is ...observed in only 8-10% of the patients with tricuspid valve disease. Secondary TR is more common and arises as a result of annular dilation caused by right ventricular enlargement and dysfunction as a consequence of pulmonary hypertension, often caused by left-sided heart disease or atrial fibrillation. Irrespective of its aetiology, TR leads to volume overload and increased wall stress, both of which negatively contribute to detrimental remodelling and worsening TR. This vicious circle translates into impaired survival and increased heart failure symptoms in patients with and without reduced left ventricular ejection fraction. Interventions to correct TR are underutilised in daily clinical practice owing to increased surgical risk and late patient presentation. The recently introduced transcatheter tricuspid valve interventions aim to address this unmet need. Dedicated expertise and an interdisciplinary Heart Team evaluation are essential to integrate these new techniques successfully and select patients. The present article proposes a standardised approach to evaluate patients with TR who may be candidates for transcatheter interventions. In addition, a state-of-the-art review of the available transcatheter therapies, the main criteria for patient and device selection, and information concerning the remaining uncertainties are provided.
Waste collection is one of the targets of smart cities. It is a daily task in urban areas and it entails the planning of waste truck routes, taking into account environmental, economic and social ...factors. In this work, an optimal path planning algorithm has been developed together with a practical software platform for smart and sustainable cities that enables computing the optimal waste collection routes, minimizing the impact, both environmental (CO
emissions and acoustic damage) and socioeconomic (number of trucks to be used and fuel consumption). The algorithm is executed in Net2Plan, an open-source planning tool, typically used for modeling and planning communication networks. Net2Plan facilitates the introduction of the city layout input information to the algorithm, automatically importing it from geographical information system (GIS) databases using the so-called Net2Plan-GIS library, which can also include positions of smart bins. The algorithm, Net2Plan tool and its extension are open-source, available in a public repository. A practical case in the city of Cartagena (Spain) is presented, where the optimal path planning for plastic waste collection is addressed. This work contributes to the urban mobility plans of smart cities and could be extended to other smart cities scenarios with requests of optimal path planning.
Chronic pressure-overload induces right ventricular (RV) adaptation to maintain RV–pulmonary arterial (PA) coupling. RV remodeling is frequently associated with secondary tricuspid regurgitation (TR) ...which may accelerate uncoupling. Our aim is to determine whether the non-invasive analysis of RV–PA coupling could improve risk stratification in patients with secondary TR. A total of 1,149 patients (median age 72IQR, 63 to 79 years, 51% men) with moderate or severe secondary TR were included. RV–PA coupling was estimated using the ratio between two standard echocardiographic measurements: tricuspid annular plane systolic excursion (TAPSE) and pulmonary artery systolic pressure (PASP). The risk of all-cause mortality across different values of TAPSE/PASP was analyzed with a spline analysis. The cut-off value of TAPSE/PASP to identify RV–PA uncoupling was based on the spline curve analysis. At the time of significant secondary TR diagnosis the median TAPSE/PASP was 0.35 (IQR, 0.25 to 0.49) mm/mm Hg. A total of 470 patients (41%) demonstrated RV–PA uncoupling (<0.31 mm/mm Hg). Patients with RV–PA uncoupling presented more frequently with heart failure symptoms had larger RV and left ventricular dimensions, and more severe TR compared to those with RV–PA coupling. During a median follow-up of 51 (IQR, 17 to 86) months, 586 patients (51%) died. The cumulative 5-year survival rate was lower in patients with RV–PA uncoupling compared to their counterparts (37% vs 64%, p < 0.001). After correcting for potential confounders, RV–PA uncoupling was the only echocardiographic parameter independently associated with all-cause mortality (HR 1.462; 95% CI 1.192 to 1.793; p < 0.001). In conclusion, RV–PA uncoupling in patients with secondary TR is independently associated with poor prognosis and may improve risk stratification.
Objectives The aim of the current study was to evaluate echocardiographic parameters after 6 months of cardiac resynchronization therapy (CRT) as well as long-term outcome in patients with the left ...ventricular (LV) lead positioned at the site of latest activation (concordant LV lead position) as compared with that seen in patients with a discordant LV lead position. Background A nonoptimal LV pacing lead position may be a potential cause for nonresponse to CRT. Methods The site of latest mechanical activation was determined by speckle tracking radial strain analysis and related to the LV lead position on chest X-ray in 244 CRT candidates. Echocardiographic evaluation was performed after 6 months. Long-term follow-up included all-cause mortality and hospitalizations for heart failure. Results Significant LV reverse remodeling (reduction in LV end-systolic volume from 189 ± 83 ml to 134 ± 71 ml, p < 0.001) was noted in the group of patients with a concordant LV lead position (n = 153, 63%), whereas patients with a discordant lead position showed no significant improvements. In addition, during long-term follow-up (32 ± 16 months), less events (combined for heart failure hospitalizations and death) were reported in patients with a concordant LV lead position. Moreover, a concordant LV lead position appeared to be an independent predictor of hospitalization-free survival after long-term CRT (hazard ratio: 0.22, p = 0.004). Conclusions Pacing at the site of latest mechanical activation, as determined by speckle tracking radial strain analysis, resulted in superior echocardiographic response after 6 months of CRT and better prognosis during long-term follow-up.
Transport ecosystems that combine software defined networking (SDN) and network function virtualization (NFV) are characterized by an unprecedented network control and resource dynamicity. Manual ...optimization is unmanageable. In this context, open systems that manage and orchestrate SDN/NFV-enabled networks offer programming frameworks that abstract the low-level particularities in the data-plane forwarding devices and in the hardware appliances that provide the IT resources. Although these open systems present notable complexity, their programming abstractions promote a client layer where third-party applications can provide different functionalities thus enabling optimization-as-a-service business opportunities. In this paper, we cover open-source optimization software initiatives for offline planning and online provisioning and orchestration of SDN/NFV networks. With this goal in mind, we first focus on open software (and framework) initiatives through a set of realistic use cases that require optimization in multi-layer optical transport scenarios and ecosystems that combine transport with IT resources. The importance of a joint optimization of both network and IT domains is emphasized, a new paradigm triggered by SDN/NFV technologies. We discuss the theoretical limits to algorithm performances, and review available open-source frameworks for problem modeling that enable the interaction with solvers. Finally, we focus on the Net2Plan open-source network planning tool, a Java-based software that suitably embraces the multiple features required in the optimization of joint transport network and IT resource SDN/NFV ecosystems. Recent works based on Net2Plan are reviewed to illustrate its suitability for rapid algorithm prototyping, and for interaction with SDN/NFV-enabled networks.
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