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1.
Catheter Cardiovasc Interv ; 103(1): 51-60, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37994226

RESUMEN

BACKGROUND: Among the two stent strategies, contemporary evidence favors double kissing crush technique (DKC) for complex unprotected distal left main bifurcation (UdLMB) lesions. However one of the major challenges to these lesions is side branch (SB) restenosis. AIMS: Our aim was to identify optical coherence tomographic (OCT) characteristics that may predict SB restenosis (SBR) after UdLMB angioplasty using DKC technique. METHODS: This was a single-center, retrospective study that included 60 patients with complex UdLMB disease, who underwent OCT-guided angioplasty using DKC technique. Angiographic follow-up was performed in all patients at 1 year to identify patients with SBR. Patients with SBR group were compared with patients without SBR (NSBR group) for OCT parameters during index procedure. RESULTS: Twelve (20%) patients developed SBR at 1-year follow-up. The SBR group had longer SB lesion (18.8 ± 3.2 vs. 15.3 ± 3.7 mm, p = 0.004) and neo-metallic carinal length (2.1 vs. 0.1 mm, p < 0.001) when compared to the NSBR group. Longer neo-metallic carinal length was associated with the absence of the dumbbell sign, presence of hanging stent struts across the SB ostium on OCT of final MB pullback. On multivariate regression analysis, SB distal reference diameter (DRD) and SB stent expansion were identified as independent predictors of SBR with SB-DRD of ≤2.8 mm (area under curve-0.73, sensitivity-83.3%, and specificity-62.5%) and SB stent expansion of ≤89% (area under curve-0.88, sensitivity-83.3%, and specificity- 81.2%) as the best cut off values to predict SBR. CONCLUSIONS: SB DRD and SB stent expansion are the OCT predictors of future SBR after UdLMB angioplasty using DKC technique.


Asunto(s)
Angioplastia Coronaria con Balón , Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Enfermedades de las Válvulas Cardíacas , Humanos , Angioplastia Coronaria con Balón/efectos adversos , Angioplastia Coronaria con Balón/métodos , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Resultado del Tratamiento , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/cirugía , Stents , Constricción Patológica , Angiografía Coronaria/métodos
2.
Catheter Cardiovasc Interv ; 104(4): 688-696, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39224005

RESUMEN

BACKGROUND: Non-eruptive calcium nodules (CNs) are commonly seen in heavily calcified coronary artery disease. They are the most difficult subset for modification, and may result in stent damage, malapposition and under-expansion. There are only limited options available for non-eruptive CN modification. Intravascular lithotripsy (IVL) is being explored as a potentially safe and effective modality in these lesions. AIMS: This study aimed to investigate the safety and efficacy of the use of IVL for the modification of non-eruptive CNs. The study also explored the OCT features of calcium nodule modification by IVL. METHODS: This is a single-center, prospective, observational study in which patients with angiographic heavy calcification and non-eruptive CN on OCT and undergoing PCI were enrolled. The primary safety endpoint was freedom from perforation, no-reflow/slow flow, flow-limiting dissection after IVL therapy, and major adverse cardiac events (MACE) during hospitalization and at 30 days. MACE was defined as a composite of cardiac death, myocardial infarction (MI), and ischemia-driven target lesion revascularization (TLR). The primary efficacy endpoint was procedural success, defined as residual diameter stenosis of <30% on angiography and stent expansion of more than 80% as assessed by OCT. RESULTS: A total of 21 patients with 54 non-eruptive CNs undergoing PCI were prospectively enrolled in the study. Before IVL, OCT revealed a mean calcium score of 3.7 ± 0.5 and a mean MLA at CN of 3.9 ± 2.1 mm2. Following IVL, OCT revealed calcium fractures in 40 out of 54 (74.1%) CNs with an average of 1.05 ± 0.72 fractures per CN. Fractures were predominantly observed at the base of the CN (80%). Post IVL, the mean MLA at CN increased to 4.9 ± 2.3 mm2. After PCI, the mean MSA at the CN was 7.9 ± 2.5 mm2. Optimal stent expansion (stent expansion >80%) at the CN was achieved in 85.71% of patients. All patients remained free from MACE during hospitalization and at the 30-day follow-up. At 1-year follow-up, all-cause death had occurred in 3 (14.3%) patients. CONCLUSIONS: This single-arm study demonstrated the safety, efficacy, and utility of the IVL in a subset of patients with non-eruptive calcified nodules. In this study, minimal procedural complications, excellent lesion modifications, and favorable 30-day and 1-year outcomes were observed.


Asunto(s)
Enfermedad de la Arteria Coronaria , Litotricia , Valor Predictivo de las Pruebas , Tomografía de Coherencia Óptica , Calcificación Vascular , Humanos , Estudios Prospectivos , Masculino , Femenino , Calcificación Vascular/diagnóstico por imagen , Calcificación Vascular/terapia , Calcificación Vascular/mortalidad , Anciano , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Litotricia/efectos adversos , Persona de Mediana Edad , Factores de Tiempo , Factores de Riesgo , Vasos Coronarios/diagnóstico por imagen , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/instrumentación , Resultado del Tratamiento , Angiografía Coronaria
3.
Sensors (Basel) ; 24(13)2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-39000859

RESUMEN

This paper investigates the performance of dual-hop unmanned aerial vehicle (UAV)-assisted communication channels, employing a decode-and-forward (DF) relay architecture. The system leverages terahertz (THz) communication for the primary hop and visible light communication (VLC) for the secondary hop. We conduct an in-depth analysis by deriving closed-form expressions for the end-to-end (E2E) bit error rate (BER). Additionally, we use a Monte Carlo simulation approach to generate best-fitting curves, validating our analytical expressions. A performance evaluation through BER and outage probability metrics demonstrates the effectiveness of the proposed system. Specifically, our results indicate that the proposed system outperforms Free-Space Optics (FSO)-VLC and Radio-Frequency (RF)-VLC at a higher signal-to-noise ratio (SNR). The results of this study provide valuable insights into the feasibility and limitations of UAV-assisted THz-VLC communication systems.

4.
Sensors (Basel) ; 21(22)2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34833665

RESUMEN

In this paper, sum capacity maximization of the non-orthogonal multiple access (NOMA)-based wireless network is studied in the presence of ambient backscattering (ABS). Assuming that ABS is located next to far nodes, it improves the signal strength of far node cluster. By applying suitable successive interference cancellation (SIC) operation, far node cluster act as an internet of things (IoT) reader. Moreover, to improve the uplink performance of the nodes, a physical layer network coding (PLNC) scheme is applied in the proposed network. Power optimization is employed at the access point (AP) to enhance the downlink performance with total transmit power constraint and minimum data rate requirement per user constraint using Lagrangian's function. In addition, end-to-end outage performance of the proposed wireless network is analyzed to enhance each wireless link capacity. Numerical results evident that the outage performance of the proposed network is significantly improved while using the ABS. Furthermore, the average bit error rate (BER) performance of the proposed wireless network is studied to improve the reliability. Simulation results are presented to validate the analytical expressions.

5.
Sensors (Basel) ; 20(21)2020 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-33113982

RESUMEN

The fog computing-based device-driven network is a promising solution for high data rates in modern cellular networks. It is a unique framework to reduce the generated-data, data management overheads, network scalability challenges, and help us to provide a pervasive computation environment for real-time network applications, where the mobile data is easily available and accessible to nearby fog servers. It explores a new dimension of the next generation network called fog networks. Fog networks is a complementary part of the cloud network environment. The proposed network architecture is a part of the newly emerged paradigm that extends the network computing infrastructure within the device-driven 5G communication system. This work explores a new design of the fog computing framework to support device-driven communication to achieve better Quality of Service (QoS) and Quality of Experience (QoE). In particular, we focus on, how potential is the fog computing orchestration framework? How it can be customized to the next generation of cellular communication systems? Next, we propose a mobility management procedure for fog networks, considering the static and dynamic mobile nodes. We compare our results with the legacy of cellular networks and observed that the proposed work has the least energy consumption, delay, latency, signaling cost as compared to LTE/LTE-A networks.

6.
Sensors (Basel) ; 20(19)2020 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-33003319

RESUMEN

Rapid emergence of wireless sensor networks (WSN) faces significant challenges due to limited battery life capacity of composing sensor nodes. It is substantial to construct efficient techniques to prolong the battery life of the connected sensors in order to derive their full potential in the future Internet of Things (IoT) paradigm. For that purpose, different energy harvesting (EH) schemes are relying on a wide array of sources. Following the same objective, in this work, we have observed a time-switching EH for half-duplex (HD) bidirectional WSN, which performed in-between relaying over Hoyt fading channels. For its comprehensive performance analysis, rapidly converging infinite-series expressions have been provided with focus on the outage probability (OP) and achievable throughput of the hardware-impaired system. Additionally, asymptotic behavior of these performance measures has also been provided. Further, an approach to the symbol-error probability (SEP) analysis is also presented in the context of the observed system. Finally, we consider the shadowing influence along the WSN propagation path. Performance analysis of observed EH system operating over Rician-shadowed fading channels has been carried out, with deriving exact corresponding infinite-series expressions for outage probability (OP) and achievable throughput of the system under the hardware impairment conditions. In addition, bidirectional relaying in a mixed fading environment has been considered.

7.
Sensors (Basel) ; 20(21)2020 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-33126709

RESUMEN

Deployment of unmanned aerial vehicles (UAVs) as aerial base stations (ABSs) has been considered to be a feasible solution to provide network coverage in scenarios where the conventional terrestrial network is overloaded or inaccessible due to an emergency situation. This article studies the problem of optimal placement of the UAVs as ABSs to enable network connectivity for the users in such a scenario. The main contributions of this work include a less complex approach to optimally position the UAVs and to assign user equipment (UE) to each ABS, such that the total spectral efficiency (TSE) of the network is maximized, while maintaining a minimum QoS requirement for the UEs. The main advantage of the proposed approach is that it only requires the knowledge of UE and ABS locations and statistical channel state information. The optimal 2-dimensional (2D) positions of the ABSs and the UE assignments are found using K-means clustering and a stable marriage approach, considering the characteristics of the air-to-ground propagation channels, the impact of co-channel interference from other ABSs, and the energy constraints of the ABSs. Two approaches are proposed to find the optimal altitudes of the ABSs, using search space constrained exhaustive search and particle swarm optimization (PSO). The numerical results show that the PSO-based approach results in higher TSE compared to the exhaustive search-based approach in dense networks, consuming similar amount of energy for ABS movements. Both approaches lead up to approximately 8-fold energy savings compared to ABS placement using naive exhaustive search.

8.
Sensors (Basel) ; 20(8)2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32316486

RESUMEN

Secure and reliable information flow is one of the main challenges in social IoT and mobile networks. Information flow and data integrity is still an open research problem. In this paper, we develop new methods of constructing systematic and regular Low-Density Parity-Check Matrices (LDPCM), inspired by the structure of the Sarrus method and geometric designs. Furthermore, these codes have cyclic structure and therefore, are less complex in computation and also require less memory in hardware implementation. Besides, an optimal method of post-processing for deleting girths four is presented. Numerical results show that the codes constructed by these methods perform well over the additive white Gaussian noise (AWGN) channel when decoded with the sum-product LDPC iterative algorithms. The proposed methods can be very efficient in terms of reducing memory consumption and improving the convergence speed of the decoder particularly in IoT and mobile networks.

9.
Sensors (Basel) ; 19(5)2019 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-30866552

RESUMEN

In this paper, we present a few novel simultaneous wireless information and power transfer (SWIPT) schemes that can be effectively used in various 5G wireless network implementations. First, we study the possibility of integrating distributed energy beamforming with the data rate fairness beamforming in a cooperative communication system with multiple cooperative relays and multiple destination users communicating simultaneously. We show that the system exploits significant performance gain using such a joint energy and data rate fairness beamforming scheme. Further, we propose an enhanced version of the SWIPT scheme, the energy-efficient modulation-based non-orthogonal multiple access (M-NOMA) SWIPT scheme, and observe its system efficiency in terms of more harvested energy. Finally, we consider an energy-harvesting SWIPT scheme where the channel response is estimated using the energy-harvesting signal as pilots superimposed on the information signal. For such a scheme, we compute the optimum transmit power ratio between the pilot and information signals under varying SNR conditions and improve the accuracy of the decoding process at the reception.

10.
Angiology ; 75(3): 231-239, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36629740

RESUMEN

The systemic immune-inflammation index (SII) and systemic inflammation response index (SIRI) have previously demonstrated predictive value in coronary artery disease (CAD). We developed on an expanded, novel systemic immune-inflammation response index (SIIRI), calculated as peripheral neutrophil × monocyte × platelet ÷ lymphocyte count. We assessed 240 patients with an acute coronary syndrome that subsequently underwent percutaneous coronary intervention. CAD severity was measured using the SYNTAX score. Laboratory measurements, including cell counts, were obtained on admission. On multivariate analysis, the SIIRI was an independent predictor of severe CAD with an adjusted odds ratio (OR) of 1.666 [1.376-2.017] per 105-unit increase. The SIIRI had the highest area under the receiver operator curve of .771 [.709-.833] compared to the SII, SIRI neutrophil-lymphocyte ratio, monocyte-lymphocyte ratio, and platelet-lymphocyte ratio. The optimal cut-off for SIIRI was 4.3 × 105, with sensitivity = 69.9% and specificity = 75.8%. Increment in model performance resulting from adding SIIRI versus other inflammatory indices was assessed using discrimination, calibration, and goodness-of-fit measures. When added to a baseline model, the SIIRI resulted in a significant increase in the c-statistic and significant net reclassification index (.808, P < .0001) and integrated discrimination index (.129, P < .0001), and a decrease in Akaike and Bayesian information criteria.


Asunto(s)
Síndrome Coronario Agudo , Enfermedad de la Arteria Coronaria , Humanos , Síndrome Coronario Agudo/diagnóstico , Teorema de Bayes , Plaquetas , Inflamación/diagnóstico , Estudios Retrospectivos
11.
PLoS One ; 18(9): e0291246, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37682906

RESUMEN

Under-five mortality (U5M) is considered a major public health issue directly impacts a country's development. This study analyzed the prognostic factors of U5M in Sri Lanka using data from the 2016 Demographic and Health Survey (DHS) of 8123 children. The study employed both a binary logistic regression model (BLRM) and a binary logistic random intercept multilevel model (BLRIMM) and compared the accuracy of each model's prediction percentage. The results showed that the BLRIMM had a higher correct prediction percentage (98.67%) compared to the BLRM (98.31%). The study found that children who were not breastfed (Odds Ratio (OR) = 116.74, 95% Confidence Interval (CI) = 62.97-216.41), were part of multiple births (OR = 3.73, 95% CI = 1.21-11.51), did not have a normal delivery (OR = 1.86, 95% CI = 1.11-3.12), were born to mothers who had experienced previous miscarriages or child loss (OR = 2.27, 95% CI = 1.26-4.11), and were born to mothers with a higher Body Mass Index (BMI) (OR = 1.05, 95% CI = 1.003-1.10) had higher odds of U5M. The odds of U5M were found to be lower among Buddhists (OR = 0.06, 95% CI = 0.01-0.50), Hindus (OR = 0.05, 95% CI = 0.01-0.46), and Roman Catholics (OR = 0.032, 95% CI = 0.003-0.307) compared to the "Other Religions" category in the dataset. The estimated covariance parameter of the random intercept (0.8231, p-value = 0.0405) indicated significant unobserved cluster-level variation in U5M. The study's results emphasize the importance of addressing religion related differences of U5M and improving maternal education regarding healthy lifestyle, proper food intake, the significance of breastfeeding, safe delivery methods, safety measures during pregnancy and childbirth in cases of multiple births, and proper child care after birth.


Asunto(s)
Aborto Espontáneo , Pueblo Asiatico , Mortalidad del Niño , Mortalidad Infantil , Femenino , Humanos , Embarazo , Madres , Análisis Multinivel , Sri Lanka/epidemiología , Lactante , Preescolar
12.
World Neurosurg ; 158: e922-e928, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34861447

RESUMEN

OBJECTIVE: To evaluate the clinical and radiological outcome of Gamma Knife radiosurgery (GKS) in treatment of intracranial dural arteriovenous fistula (DAVF) with cortical venous drainage (CVD) and compare it with the outcome of endovascular therapy. METHODS: Patients who underwent GKS or endovascular therapy for intracranial DAVF with CVD over 10 years (January 2007 to December 2016) at the All India Institute of Medical Sciences, New Delhi, were included. Demographics, clinical presentation, imaging details, and follow-up clinical status were reviewed retrospectively. Clinical follow-up was conducted once every 6 months. Radiological follow-up using digital subtraction angiography was performed at a mean 24 months after intervention. Patients with clinical follow-up of <1 year were excluded from the study. RESULTS: The study included 35 patients (26 in embolization group and 9 in GKS group) who had intracranial DAVF with CVD were included in the study. Clinical improvement was seen in 77.78% of the patients who received GKS and 57.7% of the patients who underwent embolization (P = 0.431). Complete obliteration of DAVF was seen in 55.56% of the patients in the GKS group and 57.7% of the patients in the embolization group (P = 1). GKS was at least as effective as embolization in terms of clinical and radiological outcome in treatment of intracranial DAVF with CVD. CONCLUSIONS: Contrary to popular perception, GKS should be considered as an effective first-line treatment alternative of intracranial DAVF with CVD.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central , Embolización Terapéutica , Radiocirugia , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Drenaje , Embolización Terapéutica/métodos , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
13.
Cardiovasc Revasc Med ; 34: 86-91, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-33468422

RESUMEN

OBJECTIVES: To do a quantitative comparison of saline and contrast Frequency domain optical coherence tomography (FD-OCT) during percutaneous coronary intervention (PCI) optimisation. METHODS: 13 pairs of OCT runs were analysed, wherein each pair consisted of a contrast run and a heparinized saline run taken in the same coronary artery at the same position. Quantitative analysis was done comparing minimal lumen area (MLA), proximal reference diameter (PRD), distal reference diameter (DRD) and percentage area stenosis (AS) at the same anatomical location. Lesion morphologies, rendered stent view and 3D reconstruction were compared for image clarity. RESULT: The saline OCT runs resulted in comparable MLA (3.88 ± 2.59 mm2 with saline run vs 3.88 ± 2.71 mm2 with contrast run; p = 0.650), PRD (3.66 ± 0.52 mm with saline vs 3.65 ± 0.52 mm with contrast; p = 0.463), DRD (2.97 ± 0.22 mm with saline vs 2.99 ± 0.88 mm with contrast; p = 0.433), and AS (59.60 ± 18.62% with saline vs 59.18 ± 19.11% with contrast; p = 0.753) with respect to the contrast runs. The Bland Altman plots of the measured parameters indicate good agreement between saline and contrast OCT. Linear regression analysis indicated the absence of proportional bias All lesion morphologies (calcified, fibrotic, thin cap fibroatheroma, macrophages, cholesterol crystals and edge dissection), 3D reconstruction and rendered stent view were clearly demonstrable in the saline OCT runs. CONCLUSIONS: Using heparinized saline as flushing media in coronary FD-OCT may result in vessel dimensions that are comparable with contrast. Heparinized saline may be used as a contrast saving alternative for FD-OCT during PCI optimization.


Asunto(s)
Enfermedad de la Arteria Coronaria , Intervención Coronaria Percutánea , Constricción Patológica , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/patología , Humanos , Intervención Coronaria Percutánea/efectos adversos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Tomografía de Coherencia Óptica , Resultado del Tratamiento
14.
Pediatr Neurosurg ; 47(3): 217-22, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22041663

RESUMEN

A 4-week-old infant presented with hemifacial spasms noticed from the 4th day after delivery. These progressed in severity, with generalization every 3-4 h. On admission, the infant went into refractory status epilepticus and had to be electively ventilated and taken for surgery on a semi-emergency basis. MRI showed a fourth ventricular hamartoma and video EEG showed spikes that were synchronous with the facial 'twitches' with generalization. Following the first surgery, the infant had an initial complete recovery, but developed recurrence of facial twitches after 2 weeks. Repeat MRI showed a small residual tumor which was re-operated and completely excised (at 8 weeks). Following this, the patient had complete recovery from seizures (5-year follow-up). This is the youngest patient reported presenting with status epilepticus with a fourth ventricular hamartoma operated successfully.


Asunto(s)
Encefalopatías/cirugía , Cuarto Ventrículo/cirugía , Hamartoma/cirugía , Procedimientos Neuroquirúrgicos , Estado Epiléptico/cirugía , Enfermedad Aguda , Biopsia , Encefalopatías/complicaciones , Encefalopatías/diagnóstico , Servicios Médicos de Urgencia , Femenino , Cuarto Ventrículo/diagnóstico por imagen , Cuarto Ventrículo/patología , Hamartoma/complicaciones , Hamartoma/diagnóstico , Humanos , Recién Nacido , Estado Epiléptico/diagnóstico , Estado Epiléptico/etiología , Tomografía Computarizada por Rayos X
15.
Front Cardiovasc Med ; 8: 625873, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33634171

RESUMEN

Objectives: In this study, we intend to analyze the feasibility and efficacy of very low frame rate fluoroscopy (VLFF) protocol using a combination of 3.8 and 7.5 fps while performing Percutaneous Coronary Intervention (PCI). Methods: A retrospective cohort including 193 patients undergoing PCI under the VLFF protocol (Post-VLFF group) was compared with a retrospective cohort of 133 patients, who underwent PCI prior to implementation of VLFF protocol (Pre-VLFF group). In the Pre-VLFF group, all PCIs were performed using fluoroscopy frame rate of 15 fps. In the Post-VLFF group, 3.8 fps was used to guide catheter engagement, coronary lesion wiring, pre-and post-dilation, and 7.5 fps was used for lesion assessment and stent placement. Increasing use of fluoroscopic storage in place of cineangiography was also encouraged. Cine acquisition in both groups was performed at 15 fps. Primary endpoint was radiation exposure measured by Air Kerma. Secondary endpoints were procedure related outcomes and patient related outcomes (Major Adverse Cardiac Events including all-cause mortality, Target Lesion Failure, Myocardial Infarction, and Stroke). RESULTS: Post-VLFF group showed 74.7% reduction in Air Kerma as compared to Pre-VLFF group (433 ± 27 mGy vs. 1,714 ± 140 mGy; p < 0.0001), with no increase in the fluoroscopy time (15.38 ± 0.98 min Post-VLFF vs. 17.06 ± 1.29 min Pre-VLFF; p = 0.529) and contrast volume (116.5 ± 4.9 ml Post-VLFF vs. 116.7 ± 6 ml Pre-VLFF; p = 0.700). Both groups had comparable procedural success and complications rates as well as incidence of MACE. Conclusions: The very low frame rate fluoroscopy protocol is a feasible, effective, and safe method to significantly reduce the radiation exposure during PCI without any compromise on procedural and patient outcomes.

16.
Indian Heart J ; 72(4): 239-243, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32861376

RESUMEN

AIM: The aim of this study was to evaluate the feasibility of heparinised saline as flushing media for frequency-domain optical coherence tomography (FD-OCT) image acquisition during percutaneous coronary intervention (PCI) optimisation. METHODS AND RESULTS: Twenty-seven patients undergoing FD-OCT-guided PCI were enrolled. Heparinised saline was injected into the coronary during FD-OCT image acquisition. A total of 118 runs were analysed for image quality and diagnostic value. FD-OCT runs were categorised as follows: good runs (GRs), clinically usable runs (CURs) and clinically not usable runs (NURs); GRs and CURs were combined as clinically effective runs (ERs). Saline FD-OCT enabled visualisation of all possible coronary lesions. Of the 118 runs analysed, 61%, 27.1%, 11.9% and 88.1% were GRs, CURs, NURs and ERs, respectively. Sixty-one percent of total runs were left coronary system (LCS) and 39% were right coronary system (RCS) runs. Among LCS runs, 55.6%, 30.6%, 13.8% and 86.2% were GRs, CURs, NURs and ERs, respectively. Among RCS runs, 69.6%, 21.7%, 8.7% and 91.3% were GRs, CURs, NURs and ERs, respectively. CONCLUSION: This is the first study to demonstrate the technical feasibility of isolated saline FD-OCT for PCI optimisation.


Asunto(s)
Enfermedad de la Arteria Coronaria/cirugía , Vasos Coronarios/diagnóstico por imagen , Intervención Coronaria Percutánea/métodos , Solución Salina/farmacología , Cirugía Asistida por Computador/métodos , Tomografía de Coherencia Óptica/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Vasos Coronarios/cirugía , Humanos , Valor Predictivo de las Pruebas , Estudios Prospectivos
17.
J Appl Psychol ; 101(9): 1342-51, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27599091

RESUMEN

We propose that promotive voice, or the expression of suggestions for improving work practices in the organization, and prohibitive voice, or the expression of warnings about factors that can harm the organization, are differentially influenced by employees' dispositional inclination to be approach and avoidance oriented. Drawing on multisource survey data from 291 employees and their managers, we found that approach orientation had positive relationship with promotive voice and negative relationship with prohibitive voice. By contrast, avoidance orientation had positive relationship with prohibitive voice and negative relationship with promotive voice. Further, voice role expectations, or employees' beliefs about the extent to which a particular form of voice is expected from them in their daily work, moderated the effects of approach and avoidance orientations. Highlighting the unique nature of voice as a behavior that is especially sensitive to situational cues, the effects of approach and avoidance orientations on promotive and prohibitive voice were stronger when role expectations for that form of voice were weaker. The theoretical implications of these findings are discussed. (PsycINFO Database Record


Asunto(s)
Comunicación , Empleo/psicología , Cultura Organizacional , Conducta Social , Adulto , Femenino , Humanos , Masculino
18.
J Neurosurg ; 100(5 Suppl Pediatrics): 525-9, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15287467

RESUMEN

The authors report a case of a 13-year-old boy with juvenile pilocytic astrocytoma (JPA) presenting with subarachnoid hemorrhage (SAH). The patient experienced sudden onset of headache, vomiting, and loss of consciousness. Cranial computerized tomography scanning revealed blood within basal cisterns and the third ventricle. Angiography demonstrated normal cerebral vasculature and upward displacement of the bilateral A, segments of the anterior cerebral artery. Magnetic resonance (MR) imaging revealed a chiasmatic/hypothalamic mass with evidence of hemorrhage. The mass was surgically decompressed. Histopathological examination showed evidence of JPA. In all cases of SAH in which there is blood around the third ventricle and a raised A1 segment on angiography, MR imaging should be performed. The presence of a normal sella turcica, as well as indistinct margins between the tumor and the opticochiasmatic apparatus should raise suspicion about the lesion.


Asunto(s)
Astrocitoma/complicaciones , Neoplasias Encefálicas/complicaciones , Hemorragia Subaracnoidea/etiología , Adolescente , Angiografía , Astrocitoma/patología , Astrocitoma/cirugía , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Humanos , Imagen por Resonancia Magnética , Masculino , Hemorragia Subaracnoidea/cirugía , Tomografía Computarizada por Rayos X
19.
Neurosurgery ; 72(6): 1040-53; discussion 1053, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23426148

RESUMEN

BACKGROUND: The management of basilar invagination (BI) and atlantoaxial dislocation (AAD) is a challenge. OBJECTIVE: To describe a new innovative method to reduce BI and AAD through a single-stage posterior approach. METHODS: Thirty-five patients had irreducible BI and AAD (May 2010 to April 2012). In all patients, reduction of AAD and BI was achieved by using an innovative method of distraction and spacer placement, followed by compression and extension. A C1 lateral mass/C2 translaminar screw was performed in cases where the C1 arch was not assimilated, and occipito-C2 translaminar screw fixation was performed in cases where the C1 arch was assimilated. RESULTS: Thirty-two of 35 (94%) patients improved clinically and 2 patients had stable symptoms (mean Nurick postoperative score = 1.4; preoperative score = 3.7). AAD reduced completely in 33/35 patients and >50% in 2. BI improved significantly in all patients. Solid bone fusion was demonstrated in 24 patients with at least 1-year follow-up (range, 12-39 months; mean, 19.75 + 7.09 months). The duration of surgery was 80 to 190 minutes, and blood loss was 90 to 500 mL (mean, 170 ± 35 mL). There was 1 death because of cardiac etiology and 1 morbidity (wound infection). CONCLUSION: Distractive compressive extension and reduction of BI and AAD seems to be an effective and safe method of treatment. It is different from the earlier described techniques, because it is the first procedure that uses a spacer not, only for distraction, but also as a pivot to perform extension to reduce the AAD.


Asunto(s)
Articulación Atlantoaxoidea/cirugía , Procedimientos Ortopédicos/métodos , Platibasia/cirugía , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Luxaciones Articulares/cirugía , Masculino , Persona de Mediana Edad , Proyectos Piloto , Resultado del Tratamiento , Adulto Joven
20.
J Neurointerv Surg ; 4(1): 43-4, 2012 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21990457

RESUMEN

An extremely rare variation of the (left) middle meningeal artery (MMA) originating from the basilar artery, detected incidentally during cerebral angiography, is reported. The right MMA was normal and an accessory meningeal artery arising from the maxillary artery was present on both the sides. The foramen spinosum on the variant side was absent. This abnormal origin of the MMA can be explained by the presence of a perineural arterial network in the region of the Gasserian ganglion, formed by branches of the developing basilar and stapedial arterial systems; the middle meningeal-basilar arterial channel opening up in the absence of a normally developing MMA.


Asunto(s)
Arteria Basilar/anomalías , Arteria Basilar/embriología , Cefalea/etiología , Arterias Meníngeas/anomalías , Arterias Meníngeas/embriología , Arteria Basilar/inervación , Cefalea/diagnóstico por imagen , Cefalea/embriología , Humanos , Hallazgos Incidentales , Arterias Meníngeas/inervación , Red Nerviosa/anomalías , Red Nerviosa/irrigación sanguínea , Red Nerviosa/embriología , Radiografía
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