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BACKGROUND: Computer-aided detection (CADe) systems for colonoscopy have been shown to increase small polyp detection during colonoscopy in the general population. People with Lynch syndrome represent an ideal target population for CADe-assisted colonoscopy because adenomas, the primary cancer precursor lesions, are characterised by their small size and higher likelihood of showing advanced histology. We aimed to evaluate the performance of CADe-assisted colonoscopy in detecting adenomas in individuals with Lynch syndrome. METHODS: TIMELY was an international, multicentre, parallel, randomised controlled trial done in 11 academic centres and six community centres in Belgium, Germany, Italy, and Spain. We enrolled individuals aged 18 years or older with pathogenic or likely pathogenic MLH1, MSH2, MSH6, or EPCAM variants. Participants were consecutively randomly assigned (1:1) to either CADe (GI Genius) assisted white light endoscopy (WLE) or WLE alone. A centre-stratified randomisation sequence was generated through a computer-generated system with a separate randomisation list for each centre according to block-permuted randomisation (block size 26 patients per centre). Allocation was automatically provided by the online AEG-REDCap database. Participants were masked to the random assignment but endoscopists were not. The primary outcome was the mean number of adenomas per colonoscopy, calculated by dividing the total number of adenomas detected by the total number of colonoscopies and assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT04909671. FINDINGS: Between Sept 13, 2021, and April 6, 2023, 456 participants were screened for eligibility, 430 of whom were randomly assigned to receive CADe-assisted colonoscopy (n=214) or WLE (n=216). 256 (60%) participants were female and 174 (40%) were male. In the intention-to-treat analysis, the mean number of adenomas per colonoscopy was 0·64 (SD 1·57) in the CADe group and 0·64 (1·17) in the WLE group (adjusted rate ratio 1·03 [95% CI 0·72-1·47); p=0·87). No adverse events were reported during the trial. INTERPRETATION: In this multicentre international trial, CADe did not improve the detection of adenomas in individuals with Lynch syndrome. High-quality procedures and thorough inspection and exposure of the colonic mucosa remain the cornerstone in surveillance of Lynch syndrome. FUNDING: Spanish Gastroenterology Association, Spanish Society of Digestive Endoscopy, European Society of Gastrointestinal Endoscopy, Societat Catalana de Digestologia, Instituto Carlos III, Beca de la Marato de TV3 2020. Co-funded by the European Union.
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Adenoma , Inteligência Artificial , Colonoscopia , Neoplasias Colorretais Hereditárias sem Polipose , Humanos , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Masculino , Feminino , Colonoscopia/métodos , Pessoa de Meia-Idade , Adenoma/diagnóstico , Adenoma/patologia , Adulto , Detecção Precoce de Câncer/métodos , Idoso , Diagnóstico por Computador/métodosRESUMO
Background: PolyDeep is a computer-aided detection and classification (CADe/x) system trained to detect and classify polyps. During colonoscopy, CADe/x systems help endoscopists to predict the histology of colonic lesions. Objective: To compare the diagnostic performance of PolyDeep and expert endoscopists for the optical diagnosis of colorectal polyps on still images. Methods: PolyDeep Image Classification (PIC) is an in vitro diagnostic test study. The PIC database contains NBI images of 491 colorectal polyps with histological diagnosis. We evaluated the diagnostic performance of PolyDeep and four expert endoscopists for neoplasia (adenoma, sessile serrated lesion, traditional serrated adenoma) and adenoma characterization and compared them with the McNemar test. Receiver operating characteristic curves were constructed to assess the overall discriminatory ability, comparing the area under the curve of endoscopists and PolyDeep with the chi- square homogeneity areas test. Results: The diagnostic performance of the endoscopists and PolyDeep in the characterization of neoplasia is similar in terms of sensitivity (PolyDeep: 89.05%; E1: 91.23%, p=0.5; E2: 96.11%, p<0.001; E3: 86.65%, p=0.3; E4: 91.26% p=0.3) and specificity (PolyDeep: 35.53%; E1: 33.80%, p=0.8; E2: 34.72%, p=1; E3: 39.24%, p=0.8; E4: 46.84%, p=0.2). The overall discriminative ability also showed no statistically significant differences (PolyDeep: 0.623; E1: 0.625, p=0.8; E2: 0.654, p=0.2; E3: 0.629, p=0.9; E4: 0.690, p=0.09). In the optical diagnosis of adenomatous polyps, we found that PolyDeep had a significantly higher sensitivity and a significantly lower specificity. The overall discriminative ability of adenomatous lesions by expert endoscopists is significantly higher than PolyDeep (PolyDeep: 0.582; E1: 0.685, p < 0.001; E2: 0.677, p < 0.0001; E3: 0.658, p < 0.01; E4: 0.694, p < 0.0001). Conclusion: PolyDeep and endoscopists have similar diagnostic performance in the optical diagnosis of neoplastic lesions. However, endoscopists have a better global discriminatory ability than PolyDeep in the optical diagnosis of adenomatous polyps.
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New applications are continuously appearing with drones as protagonists, but all of them share an essential critical maneuver-landing. New application requirements have led the study of novel landing strategies, in which vision systems have played and continue to play a key role. Generally, the new applications use the control and navigation systems embedded in the aircraft. However, the internal dynamics of these systems, initially focused on other tasks such as the smoothing trajectories between different waypoints, can trigger undesired behaviors. In this paper, we propose a landing system based on monocular vision and navigation information to estimate the helipad global position. In addition, the global estimation system includes a position error correction module by cylinder space transformation and a filtering system with a sliding window. To conclude, the landing system is evaluated with three quality metrics, showing how the proposed correction system together with stationary filtering improves the raw landing system.
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Dispositivos Ópticos , AeronavesRESUMO
BACKGROUND: The "diagnose-and-leave-in" policy has been established to reduce the risks and costs related to unnecessary polypectomies in the average-risk population. In individuals with Lynch syndrome, owing to accelerated carcinogenesis, the general recommendation is to remove all polyps, irrespective of size, location, and appearance. We evaluated the feasibility and safety of the diagnose-and-leave-in strategy in individuals with Lynch syndrome. METHODS : We performed a post hoc analysis based on per-polyp data from a randomized, clinical trial conducted by 24 dedicated colonoscopists at 14 academic centers, in which 256 patients with confirmed Lynch syndrome underwent surveillance colonoscopy from July 2016 to January 2018. In vivo optical diagnosis with confidence level for all detected lesions was obtained before polypectomy using virtual chromoendoscopy alone or with dye-based chromoendoscopy. Primary outcome was the negative predictive value (NPV) for neoplasia of high-confidence optical diagnosis among diminutive (≤â5âmm) rectosigmoid lesions. Histology was the reference standard. RESULTS: Of 147 rectosigmoid lesions, 128 were diminutive. In 103 of the 128 lesions (81â%), the optical diagnostic confidence was high and showed an NPV of 96.0â% (95â% confidence interval [CI] 88.9â%-98.6â%) and accuracy of 89.3â% (95â%CI 81.9â%-93.9â%). By following the diagnose-and-leave-in policy, we would have avoided 59â% (75/128) of polypectomies at the expense of two diminutive low grade dysplastic adenomas and one diminutive sessile serrated lesion that would have been left in situ. CONCLUSION: In patients with Lynch syndrome, the diagnose-and-leave-in strategy for diminutive rectosigmoid polyps would be feasible and safe.
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Pólipos do Colo , Neoplasias Colorretais Hereditárias sem Polipose , Neoplasias Colorretais , Pólipos do Colo/diagnóstico por imagem , Pólipos do Colo/cirurgia , Colonoscopia , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Humanos , Imagem de Banda EstreitaRESUMO
Certain difficulties in path forecasting and filtering problems are based in the initial hypothesis of estimation and filtering techniques. Common hypotheses include that the system can be modeled as linear, Markovian, Gaussian, or all at one time. Although, in many cases, there are strategies to tackle problems with approaches that show very good results, the associated engineering process can become highly complex, requiring a great deal of time or even becoming unapproachable. To have tools to tackle complex problems without starting from a previous hypothesis but to continue to solve classic challenges and sharpen the implementation of estimation and filtering systems is of high scientific interest. This paper addresses the forecast-filter problem from deep learning paradigms with a neural network architecture inspired by natural language processing techniques and data structure. Unlike Kalman, this proposal performs the process of prediction and filtering in the same phase, while Kalman requires two phases. We propose three different study cases of incremental conceptual difficulty. The experimentation is divided into five parts: the standardization effect in raw data, proposal validation, filtering, loss of measurements (forecasting), and, finally, robustness. The results are compared with a Kalman filter, showing that the proposal is comparable in terms of the error within the linear case, with improved performance when facing non-linear systems.
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A 26-year-old male diagnosed with cutaneous leukocytoclastic vasculitis was admitted due to abdominal pain and rectal bleeding with slight clinical-analytical impact. On examination, he presented multiple palpable purpuric lesions on his legs.
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Endoscopia por Cápsula , Vasculite Leucocitoclástica Cutânea , Adulto , Humanos , Intestinos , Masculino , Pele , Vasculite Leucocitoclástica Cutânea/diagnósticoRESUMO
BACKGROUND & AIMS: Dye-based pancolonic chromoendoscopy is recommended for colorectal cancer surveillance in patients with Lynch syndrome. However, there is scarce evidence to support its superiority to high-definition white-light endoscopy. We performed a prospective study assess whether in the hands of high detecting colonoscopists, high-definition, white-light endoscopy is noninferior to pancolonic chromoendoscopy for detection of adenomas in patients with Lynch syndrome. METHODS: We conducted a parallel controlled study, from July 2016 through January 2018 at 14 centers in Spain of adults with pathogenic germline variants in mismatch repair genes (60% women; mean age, 47 ± 14 years) under surveillance. Patients were randomly assigned to groups that underwent high-definition white-light endoscopy (n = 128) or pancolonic chromoendoscopy (n = 128) evaluations by 24 colonoscopists who specialized in detection of colorectal lesions in high-risk patients for colorectal cancer. Adenoma detection rates (defined as the proportion of patients with at least 1 adenoma) were compared between groups, with a noninferiority margin (relative difference) of 15%. RESULTS: We found an important overlap of confidence intervals (CIs) and no significant difference in adenoma detection rates by pancolonic chromoendoscopy (34.4%; 95% CI 26.4%-43.3%) vs white-light endoscopy (28.1%; 95% CI 21.1%-36.4%; P = .28). However, pancolonic chromoendoscopy detected serrated lesions in a significantly higher proportion of patients (37.5%; 95% CI 29.5-46.1) than white-light endoscopy (23.4%; 95% CI 16.9-31.4; P = .01). However, there were no significant differences between groups in proportions of patients found to have serrated lesions of 5 mm or larger (9.4% vs 7.0%; P = .49), of proximal location (11.7% vs 10.2%; P = .68), or sessile serrated lesions (3.9% vs 5.5%; P = .55), respectively. Total procedure and withdrawal times with pancolonic chromoendoscopy (30.7 ± 12.8 minutes and 18.3 ± 7.6 minutes, respectively) were significantly longer than with white-light endoscopy (22.4 ± 8.7 minutes and 13.5 ± 5.6 minutes; P < .001). CONCLUSIONS: In a randomized parallel trial, we found that for Lynch syndrome surveillance, high-definition white-light endoscopy is not inferior to pancolonic chromoendoscopy if performed by experienced and dedicated endoscopists. ClinicalTrials.gov no: NCT02951390.
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Adenoma/diagnóstico , Colonoscopia/métodos , Neoplasias Colorretais Hereditárias sem Polipose/complicações , Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/métodos , Vigilância da População/métodos , Adenoma/congênito , Adulto , Neoplasias Colorretais/congênito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND: Symptom based referral criteria for colorectal cancer (CRC) detection are the cornerstone of the strategy to improve prognosis in CRC. In 2017, the National Institute for Health and Care Excellence (NICE) updated their referral criteria (2017 NG12). Recently, several studies have evaluated the faecal haemoglobin (f-Hb) concentration in this setting. The aim of this study is to evaluate the diagnostic accuracy of the 2017 NG12 referral criteria and to compare them with the CG27 referral criteria, the f-Hb concentration and two f-Hb based prediction model: COLONPREDICT and FAST Score. METHODS: This is a post-hoc diagnostic test study performed within the COLONPREDICT study database (1572 patients, CRC prevalence 13.6%). We assessed symptoms, the 2017 NG12 and CG27 referral criteria and determined the f-Hb before performing a colonoscopy. We compared the discriminatory ability using the area under the curve (AUC) and the sensitivity and specificity at pre-stablished thresholds with the McNemar's test. RESULTS: The 2017 NG12 referral criteria discriminatory ability (AUC 0.53; 95% confidence interval- CI 0.49-0.57) was inferior to the CG27 version (AUC 0.59; 95% CI 0.55-0.63; p = 0.01), the f-Hb concentration (AUC 0.86; 95% CI 0.84-0-89; p < 0.001), the COLONPREDICT Score (AUC 0.92; 95% CI 0.91-0.94; p < 0.001) or the FAST Score (AUC 0.87; 95% CI 0.85-0.89; p < 0.001). The number of patients meeting each criteria were as follows: 2017 NG12 and CG27 = 94.1% and 52.2%; f-Hb ≥20 and ≥ 10 µg/g faeces = 38.6 and 44.3%; COLONPREDICT Score ≥ 5.6 and ≥ 3.2 = 29.4 and 63.2% and FAST Score ≥ 4.50 and ≥ 2.12 = 37.1 and 87.0%. The 2017 NG12 criteria were more sensitive (100%) than the CG27 criteria (68.2%), the f-Hb (≥20 µg/g) (91.2%), the f-Hb (≥10 µg/g) (93.5%), the COLONPREDICT Score (≥5.6) (90.1%) and the FAST Score (≥4.50) (89.8%) (p ≤ 0.001) and equivalent to the COLONPREDICT Score (≥3.5) (99.5%) or the FAST Score (≥2.12) (100.0%) (p = 1). However, their specificity (6.8%) was significantly lower than any of the evaluated criteria (50.3%, 69.6%, 63.4%, 78.7%, 45.8%, 71.3%, 13.9%; p < 0.001). CONCLUSION: Referral criteria based on f-Hb measurement, either as a single test or within prediction models, are more accurate than symptom-based referral criteria for CRC detection in symptomatic patients.
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Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/métodos , Fezes/química , Hemoglobinas/análise , Imunoquímica/métodos , Encaminhamento e Consulta , Adulto , Área Sob a Curva , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e EspecificidadeRESUMO
We aimed to identify the plasma miRNA profile of antiphospholipid syndrome (APS) patients and to investigate the potential role of specific circulating miRNAs as non-invasive disease biomarkers. Ninety APS patients and 42 healthy donors were recruited. Profiling of miRNAs by PCR-array in plasma of APS patients identified a set of miRNAs differentially expressed and collectively involved in clinical features. Logistic regression and ROC analysis identified a signature of 10 miRNA ratios as biomarkers of disease. In addition, miRNA signature was related to fetal loss, atherosclerosis, and type of thrombosis, and correlated with parameters linked to inflammation, thrombosis, and autoimmunity. Hard clustering analysis differentiated 3 clusters representing different thrombotic risk profile groups. Significant differences between groups for several miRNA ratios were found. Moreover, miRNA signature remained stable over time, demonstrated by their analysis three months after the first sample collection. Parallel analysis in two additional cohorts of patients, including thrombosis without autoimmune disease, and systemic lupus erythematosus without antiphospholipid antibodies, each displayed specific miRNA profiles that were distinct from those of APS patients. In vitro, antiphospholipid antibodies of IgG isotype promoted deregulation in selected miRNAs and their potential atherothrombotic protein targets in monocytes and endothelial cells. Taken together, differentially expressed circulating miRNAs in APS patients, modulated at least partially by antiphospholipid antibodies of IgG isotype, might have the potential to serve as novel biomarkers of disease features and to typify patients' atherothrombotic status, thus constituting a useful tool in the management of the disease.
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Síndrome Antifosfolipídica/complicações , Aterosclerose/diagnóstico , Biomarcadores/análise , MicroRNA Circulante/genética , Regulação Neoplásica da Expressão Gênica , Trombose/diagnóstico , Adulto , Idoso , Síndrome Antifosfolipídica/fisiopatologia , Aterosclerose/etiologia , Aterosclerose/patologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Trombose/etiologia , Trombose/patologia , Adulto JovemRESUMO
PURPOSE: The aim of this study was to assess the intraoperator and interoperator agreement for manual measurements of intima-media thickness (IMT) performed under a strict carotid ultrasound technical protocol. METHODS: Two blinded experienced operators independently performed an ultrasound examination at the distal common carotid of 242 subjects in the same patient's position, diastolic phase, probe type, zooming, and depth. Thirty-six subjects were reevaluated in another time point. Three different-angle manual measurements (IMTindiv) were obtained. Interoperator agreements for each IMTindiv, and their mean (IMTmean) and maximum (IMTmax) values, were assessed with the intraclass correlation coefficient and Bland-Altman analysis. Intraoperator agreement was tested taking advantage of the second ultrasound round in 36 subjects. RESULTS: IMTmean agreements (intraoperator, 0.665-0.913; interoperator, 0.856-0.897) were higher than IMTmax (intraoperator, 0.435-0.793; interoperator, 0.631-0.718) and any IMTindiv (intraoperator, 0.355-0.676; interoperator, 0.590-0.717). Despite the small systematic error for IMTmean (intraoperator, ≤0.03; interoperator, ≤0.02 mm), at best of times, the sampling error size reached at least 0.28 and 0.25 mm for intraoperator and interoperator agreements, respectively, and was never less than 0.13 mm. CONCLUSIONS: Although IMTmean agreement is excellent under a strict protocol, limits of agreement might be too wide to consider carotid ultrasound a robust cardiovascular risk biomarker.
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Aterosclerose/diagnóstico por imagem , Espessura Intima-Media Carotídea , Variações Dependentes do Observador , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Fatores de Risco , Adulto JovemRESUMO
The limited efficiency of current air traffic systems will require a next-generation of Smart Air Traffic System (SATS) that relies on current technological advances. This challenge means a transition toward a new navigation and air-traffic procedures paradigm, where pilots and air traffic controllers perform and coordinate their activities according to new roles and technological supports. The design of new Human-Computer Interactions (HCI) for performing these activities is a key element of SATS. However efforts for developing such tools need to be inspired on a parallel characterization of hypothetical air traffic scenarios compatible with current ones. This paper is focused on airborne HCI into SATS where cockpit inputs came from aircraft navigation systems, surrounding traffic situation, controllers' indications, etc. So the HCI is intended to enhance situation awareness and decision-making through pilot cockpit. This work approach considers SATS as a system distributed on a large-scale with uncertainty in a dynamic environment. Therefore, a multi-agent systems based approach is well suited for modeling such an environment. We demonstrate that current methodologies for designing multi-agent systems are a useful tool to characterize HCI. We specifically illustrate how the selected methodological approach provides enough guidelines to obtain a cockpit HCI design that complies with future SATS specifications.
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Background. Gastroduodenal ulcer bleeding is a common medical emergency. The aim of this study was to analyze the characteristics of bleeding episodes and to identify changes in the clinical trends over seven years. Methods. Retrospective observational clinical study on a cohort of 272 consecutive adult patients with peptic ulcer bleeding, during the 2006-2012 period. Results. Mean annual admission rate was 12.8 per 100.000 inhabitants. Men were predominant (71%), with a mean age of 66.6 years. Comorbidities were present in 131 cases (48.2%) and 156 patients (57.4%) had received ulcerogenic drugs. Duodenal ulcer was the commonest location (61%). Endoscopic therapy was necessary in 183 cases (67.3%) and rebleeding occurred in 30 patients (11%). Overall mortality rate was 5.5%, with a significant association with the presence of comorbidities (P < 0.01). There were no differences in trends of annual hospitalization, clinical features at presentation, and outcomes during this 7-years period. Conclusions. Annual hospitalization rates and prognosis of peptic ulcer bleeding have remained unchanged in the study period. This may be due to the fact that the effect of improved approach on this condition is probably counteracted by risk factors such as older age, severe comorbidities, and ulcerogenic drugs consumption, which have also remained stable over recent years.
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Wilson's Disease (WD) is an autosomal recessive disorder of copper metabolism resulting in a pathological accumulation of this metal, initially in the liver and later in other organs, mainly brain. Treatment with copper chelating agents and zinc salts results in a depletion of copper deposits and prevents or reverses the clinical manifestations. Copper deficiency may cause haematological and neurological changes, the latter principally being polyneuropathy and myelopathy. We report a patient with WD who developed a myelopathy associated with a deficiency of copper following prolonged treatment with D-penicillamine and zinc salts.
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Quelantes/efeitos adversos , Terapia por Quelação/efeitos adversos , Cobre/deficiência , Degeneração Hepatolenticular/complicações , Penicilamina/efeitos adversos , Polineuropatias/induzido quimicamente , Doenças da Medula Espinal/induzido quimicamente , Zinco/efeitos adversos , Ceruloplasmina/análise , Quelantes/uso terapêutico , Cobre/farmacocinética , Cobre/urina , Feminino , Transtornos Neurológicos da Marcha/induzido quimicamente , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/metabolismo , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Exame Neurológico , Penicilamina/uso terapêutico , Polineuropatias/diagnóstico , Reflexo Anormal , Transtornos de Sensação/induzido quimicamente , Doenças da Medula Espinal/diagnóstico , Zinco/farmacocinética , Zinco/uso terapêuticoRESUMO
AIMS: To determine, in a non-selected population of 282 implantable cardioverter-defibrillator (ICD) patients with left ventricular dysfunction, the influence of the dose of beta-blockers on antitachycardia pacing (ATP) effectiveness and on the incidence of shock due to monomorphic ventricular tachycardias (VT). METHODS AND RESULTS: We followed 282 ICD patients along 26 +/- 19 months. Antitachycardia pacing and shock programming were standardized. We determined the indexed dose equivalent of beta-blockers (IDE-BB), using metoprolol as a reference, at each VT presentation. The median of IDE-BB was 55 mg/m(2)/day. We analysed 846 VT occurred in 100 patients. The ATP success rate was 84%. Upon classification of the events into three groups (IDE-BB = 0, IDE-BB < 55, and IDE-BB > or = 55), the frequency of effective ATP increased with the IDE-BB: 75 vs. 83 vs. 92% (P < 0.001). According to logistic regression, IDE-BB remained as an independent predictor of effective ATP (P < 0.001) and VT-related shock (P = 0.001). Both the mean ATP effectiveness per patient (67 vs. 80 vs. 91%, P = 0.007) and the mean survival time free of VT-related shock (583 vs. 847 vs. 1158 days, P = 0.019, log-rank test) increased linearly with the dose of beta-blockers. CONCLUSION: Beta-blockers increase the effectiveness of ATP through a dose-dependent effect. As a result, they reduce the incidence of shocks due to VT.
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Antagonistas Adrenérgicos beta/uso terapêutico , Estimulação Cardíaca Artificial , Desfibriladores Implantáveis , Metoprolol/uso terapêutico , Taquicardia Ventricular/prevenção & controle , Antagonistas Adrenérgicos beta/administração & dosagem , Idoso , Terapia Combinada , Relação Dose-Resposta a Droga , Feminino , Humanos , Modelos Logísticos , Masculino , Metoprolol/administração & dosagem , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND: In implantable cardioverter-defibrillators (ICD) patients, the duration of the basal QRS complex (QRSd) is not associated with a greater risk of developing ventricular tachyarrhythmias. QRSd could be inversely related to the effectiveness of antitachycardia pacing (ATP) because it may be associated with longer conduction times of the paced-impulses and hence, with a greater propensity to require shocks to terminate ventricular tachycardias (VTs). METHODS: We followed 216 ICD patients (pacing site: right ventricular apex; QRSd