Applications of control theory

Applications of control theory are considered in the areas of decoupling and wake steering control of submersibles, a method of electrohydraulic conversion with no moving parts, and socio-economic system modelling

The comparative responsiveness of Hospital Universitario Princesa Index and other composite indices for assessing rheumatoid arthritis activity

Objective To evaluate the responsiveness in terms of correlation of the Hospital Universitario La Princesa Index (HUPI) comparatively to the traditional composite indices used to assess disease activity in rheumatoid arthritis (RA), and to compare the performance of HUPI-based response criteria with that of the EULAR response criteria. Methods Secondary data analysis from the following studies: ACT-RAY (clinical trial), PROAR (early RA cohort) and EMECAR (pre-biologic era long term RA cohort). Responsiveness was evaluated by: 1) comparing change from baseline (Delta) of HUPI with Delta in other scores by calculating correlation coefficients; 2) calculating standardised effect sizes. The accuracy of response by HUPI and by EULAR criteria was analyzed using linear regressions in which the dependent variable was change in global assessment by physician (Delta GDA-Phy). Results Delta HUPI correlation with change in all other indices ranged from 0.387 to 0.791); HUPI's standardized effect size was larger than those from the other indices in each database used. In ACT-RAY, depending on visit, between 65 and 80% of patients were equally classified by HUPI and EULAR response criteria. However, HUPI criteria were slightly more stringent, with higher percentage of patients classified as non-responder, especially at early visits. HUPI response criteria showed a slightly higher accuracy than EULAR response criteria when using Delta GDA-Phy as gold standard. Conclusion HUPI shows good responsiveness in terms of correlation in each studied scenario (clinical trial, early RA cohort, and established RA cohort). Response criteria by HUPI seem more stringent than EULAR's

Permanent Pacemaker Implantation Following Valve-in-Valve Transcatheter Aortic Valve Replacement: VIVID Registry

Background: Permanent pacemaker implantation (PPI) remains one of the main drawbacks of transcatheter aortic valve replacement (TAVR), but scarce data exist on PPI after valve-in-valve (ViV) TAVR, particularly with the use of newer-generation transcatheter heart valves (THVs). Objectives: The goal of this study was to determine the incidence, factors associated with, and clinical impact of PPI in a large series of ViV-TAVR procedures. Methods: Data were obtained from the multicenter VIVID Registry and included the main baseline and procedural characteristics, in-hospital and late (median follow-up: 13 months [interquartile range: 3 to 41 months]) outcomes analyzed according to the need of periprocedural PPI. All THVs except CoreValve, Cribier-Edwards, Sapien, and Sapien XT were considered to be new-generation THVs. Results: A total of 1,987 patients without prior PPI undergoing ViV-TAVR from 2007 to 2020 were included. Of these, 128 patients (6.4%) had PPI after TAVR, with a significant decrease in the incidence of PPI with the use of new-generation THVs (4.7% vs. 7.4%; p = 0.017), mainly related to a reduced PPI rate with the Evolut R/Pro versus CoreValve (3.7% vs. 9.0%; p = 0.002). There were no significant differences in PPI rates between newer-generation balloon- and self-expanding THVs (6.1% vs. 3.9%; p = 0.18). In the multivariable analysis, older age (odds ratio [OR]: 1.05 for each increase of 1 year; 95% confidence interval [CI]: 1.02 to 1.07; p = 0.001), larger THV size (OR: 1.10; 95% CI: 1.01 to 1.20; p = 0.02), and previous right bundle branch block (OR: 2.04; 95% CI: 1.00 to 4.17; p = 0.05) were associated with an increased risk of PPI. There were no differences in 30-day mortality between the PPI (4.7%) and no-PPI (2.7%) groups (p = 0.19), but PPI patients exhibited a trend toward higher mortality risk at follow-up (hazard ratio: 1.39; 95% CI: 1.02 to 1.91; p = 0.04; p = 0.08 after adjusting for age differences between groups). Conclusions: In a contemporary large series of ViV-TAVR patients, the rate of periprocedural PPI was relatively low, and its incidence decreased with the use of new-generation THV systems. PPI following ViV-TAVR was associated with a trend toward increased mortality at follow-up

Surgical Treatment of Patients With Infective Endocarditis After Transcatheter Aortic Valve Implantation

Background: The optimal treatment of patients developing infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) is uncertain. Objectives: The goal of this study was to investigate the clinical characteristics and outcomes of patients with TAVI-IE treated with cardiac surgery and antibiotics (IE-CS) compared with patients treated with antibiotics alone (IE-AB). Methods: Crude and inverse probability of treatment weighting analyses were applied for the treatment effect of cardiac surgery vs medical therapy on 1-year all-cause mortality in patients with definite TAVI-IE. The study used data from the Infectious Endocarditis after TAVI International Registry. Results: Among 584 patients, 111 patients (19%) were treated with IE-CS and 473 patients (81%) with IE-AB. Compared with IE-AB, IE-CS was not associated with a lower in-hospital mortality (HRunadj: 0.85; 95% CI: 0.58-1.25) and 1-year all-cause mortality (HRunadj: 0.88; 95% CI: 0.64-1.22) in the crude cohort. After adjusting for selection and immortal time bias, IE-CS compared with IE-AB was also not associated with lower mortality rates for in-hospital mortality (HRadj: 0.92; 95% CI: 0.80-1.05) and 1-year all-cause mortality (HRadj: 0.95; 95% CI: 0.84-1.07). Results remained similar when patients with and without TAVI prosthesis involvement were analyzed separately. Predictors for in-hospital and 1-year all-cause mortality included logistic EuroSCORE I, Staphylococcus aureus, acute renal failure, persistent bacteremia, and septic shock. Conclusions: In this registry, the majority of patients with TAVI-IE were treated with antibiotics alone. Cardiac surgery was not associated with an improved all-cause in-hospital or 1-year mortality. The high mortality of patients with TAVI-IE was strongly linked to patients’ characteristics, pathogen, and IE-related complications

Infective Endocarditis Caused by Staphylococcus aureus After Transcatheter Aortic Valve Replacement

Background: Staphylococcus aureus (SA) has been extensively studied as causative microorganism of surgical prosthetic-valve infective endocarditis (IE). However, scarce evidence exists on SA IE after transcatheter aortic valve replacement (TAVR). Methods: Data were obtained from the Infectious Endocarditis After TAVR International Registry, including patients with definite IE after TAVR from 59 centres in 11 countries. Patients were divided into 2 groups according to microbiologic etiology: non-SA IE vs SA IE. Results: SA IE was identified in 141 patients out of 573 (24.6%), methicillin-sensitive SA in most cases (115/141, 81.6%). Self-expanding valves were more common than balloon-expandable valves in patients presenting with early SA IE. Major bleeding and sepsis complicating TAVR, neurologic symptoms or systemic embolism at admission, and IE with cardiac device involvement (other than the TAVR prosthesis) were associated with SA IE (P < 0.05 for all). Among patients with IE after TAVR, the likelihood of SA IE increased from 19% in the absence of those risk factors to 84.6% if ≥ 3 risk factors were present. In-hospital (47.8% vs 26.9%; P < 0.001) and 2-year (71.5% vs 49.6%; P < 0.001) mortality rates were higher among patients with SA IE vs non-SA IE. Surgery at the time of index SA IE episode was associated with lower mortality at follow-up compared with medical therapy alone (adjusted hazard ratio 0.46, 95% CI 0.22-0.96; P = 0.038). Conclusions: SA IE represented approximately 25% of IE cases after TAVR and was associated with very high in-hospital and late mortality. The presence of some features determined a higher likelihood of SA IE and could help to orientate early antibiotic regimen selection. Surgery at index SA IE was associated with improved outcomes, and its role should be evaluated in future studies

Mitral Valve Infective Endocarditis after Trans-Catheter Aortic Valve Implantation

Scarce data exist on mitral valve (MV) infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI). This multicenter study included a total of 579 patients with a diagnosis of definite IE after TAVI from the IE after TAVI International Registry and aimed to evaluate the incidence, characteristics, management, and outcomes of MV-IE after TAVI. A total of 86 patients (14.9%) had MV-IE. These patients were compared with 284 patients (49.1%) with involvement of the transcatheter heart valve (THV) only. Two factors were found to be associated with MV-IE: the use of self-expanding valves (adjusted odds ratio 2.49, 95% confidence interval [CI] 1.23 to 5.07, p = 0.012), and the presence of an aortic regurgitation ≥2 at discharge (adjusted odds ratio 3.33; 95% CI 1.43 to 7.73, p <0.01). There were no differences in IE timing and causative microorganisms between groups, but surgical management was significantly lower in patients with MV-IE (6.0%, vs 21.6% in patients with THV-IE, p = 0.001). All-cause mortality rates at 2-year follow-up were high and similar between patients with MV-IE (51.4%, 95% CI 39.8 to 64.1) and patients with THV-IE (51.5%, 95% CI 45.4 to 58.0) (log-rank p = 0.295). The factors independently associated with increased mortality risk in patients with MV-IE were the occurrence of heart failure (adjusted p <0.001) and septic shock (adjusted p <0.01) during the index hospitalization. One of 6 IE episodes after TAVI is localized on the MV. The implantation of a self-expanding THV and the presence of an aortic regurgitation ≥2 at discharge were associated with MV-IE. Patients with MV-IE were rarely operated on and had a poor prognosis at 2-year follow-up