Metabolome analysis in patients with heart failure and implantable cardioverter defibrillators.

Heart failure (HF) is a complex, heterogeneous syndrome with several comorbidities, often life-threatening and requires urgent therapy. In HF, metabolic alterations that can be assessed using comprehensive plasma, and tissue profiling will help establish new biomarkers and therapeutic targets. Metabolomic analysis of sudden death in HF cases remains unresolved. We prospectively evaluated 19 patients who underwent implantable cardioverter defibrillator (ICD) placement for the primary prevention of sudden cardiac death (SCD). Metabolomic analysis was performed using plasma samples before ICD implantation. Ventricular arrhythmia (VA)/SCD was defined as VA with an appropriate ICD therapy or SCD. During a median follow-up of 29 months (range, 13-35 months), four patients developed VA and one patient developed SCD. Using metabolomic analysis, arginine, lysine, and valine were significantly reduced in patients with VA/SCD (n = 5) compared with those without VA/SCD (n = 14). The molecules involved in energy metabolism might be associated with VA/SCD, thus requiring further investigation as a predictive value of metabolomic analysis of VA/SCD.

[Telemedicine for patients with cardiac implants : Insights into everyday practice of remote monitoring in Germany in 2022]. / Telemedizinische Versorgung von Patienten mit kardialen Implantaten : Einblick in die telekardiologische Versorgungsrealität in Deutschland im Jahr 2022.

BACKGROUND: As telemedical structures continues to be developed in the German healthcare system, remote monitoring is becoming increasingly important to ensure comprehensive, outpatient, and tailored care. The national quality assurance measure "DOQUVIDE-Documentation of quality in the assessment of vital parameters by implanted devices" is used to provide insight into everyday care for patients with telemedicine-enabled devices in Germany. METHODS: DOQUVIDE is a measuring instrument for recording outpatient remote monitoring for patients with implanted pacemaker, implantable cardioverter defibrillator (ICD), cardiac resynchronization therapy with a pacemaker (CRT-P), CRT defibrillator (CRT-D) devices and event recorder. DOQUVIDE records telemedically measured vital signs as well as cardiac events and the associated procedures initiated by cardiologists using standardized forms. RESULTS: In 74 practices/clinics in 14 federal states, 6687 patients received telemedical care in 2022; 937 were newly enrolled. These (60% male) were on average 77.8 years old, mainly with New York Heart Association (NYHA) class II (62.6%). A total of 5801 electronic records were generated as a result of telecardiology events, of which 3590 were due to pathological atrial fibrillation and 1812 due to ventricular high-frequency episodes. 295 events were triggered by event recorders and 95 by device therapies. The main measures taken were telephone contacts or outpatient visits. CONCLUSION: Remote monitoring has become a reality in German healthcare. Standardized processes and the establishment of quality assurance measures enable the definition of common quality standards and the identification of the potential for further development and simplify implementation in day-to-day care for practices.

Preditores de Qualidade de Vida, Ansiedade e Aceitação em Pacientes com Cardioversor-Desfibrilador Implantável / Predictors of Quality of Life, Anxiety and Acceptance in Patients with Implantable Cardioverter-Defibrillator

Resumo Fundamento O cardioversor-desfibrilador implantável (CDI) pode causar níveis elevados de ansiedade e depressão, resultando em efeitos negativos na qualidade de vida. Objetivos Avaliar a qualidade de vida, a ansiedade e a aceitação do CDI por meio de instrumentos de medida padronizados e identificar preditores de melhores respostas para cada um dos desfechos estudados. Método Coorte prospectiva com pacientes submetidos a implante inicial de CDI ou reoperação para a manutenção do dispositivo. Os desfechos do estudo incluíram: qualidade de vida, ansiedade e aceitação do CDI. A mudança nos escores (30 e 180 dias) foi avaliada por meio da diferença mínima importante (DMI). Foi utilizada a análise univariada e o modelo de regressão logística multivariada para a identificação de preditores de melhores respostas, adotando-se o nível de significância de 5%. Resultados De janeiro/2020 a junho/2021 foram incluídos 147 pacientes, com idade média de 55,3 ± 13,4 anos e predomínio do sexo masculino (72,1%). A DMI para qualidade de vida, a ansiedade e a aceitação do CDI foram observadas em 33 (22,4%), 36 (24,5%) e 43 (29,3%) pacientes, respectivamente. Idade igual ou maior que 60 anos (OR=2,5; IC 95%=1,14-5,53; p=0,022), ausência de fibrilação atrial (OR=3,8; IC 95%=1,26-11,63; p=0,017) e sexo feminino (OR=2,2; IC 95%=1,02-4,97; p=0,045) foram preditores independentes de melhores respostas para qualidade de vida, ansiedade e aceitação do CDI, respectivamente. Conclusão A identificação de preditores para melhores escores de qualidade de vida, ansiedade e aceitação do dispositivo pode subsidiar a implementação de cuidados específicos para os pacientes com maiores chances de apresentar resultados desfavoráveis.

Abstract Background An implantable cardioverter-defibrillator (ICD) can cause high levels of anxiety and depression, resulting in negative effects on quality of life. Objectives To evaluate the quality of life, anxiety, and acceptance of the ICD using standardized measurement instruments and identify predictors of better responses for each of the outcomes studied. Method This is a prospective cohort study with patients undergoing initial ICD implantation or reoperation to maintain the device. The study outcomes included quality of life, anxiety, and acceptance of the ICD. The change in scores (30 and 180 days) was assessed using the minimal important difference (MID). Univariate analysis and the multivariate logistic regression model were used to identify predictors of better responses, adopting a significance level of 5%. Results A total of 147 patients were included between January/2020 to June/2021, with a mean age of 55.3 ± 13.4 years and a predominance of males (72.1%). The MID for quality of life, anxiety, and ICD acceptance were observed in 33 (22.4%), 36 (24.5%) and 43 (29.3%) patients, respectively. Age equal to or greater than 60 years (OR=2.5; 95%CI=1.14-5.53; p=0.022), absence of atrial fibrillation (OR=3.8; 95%CI=1.26-11.63; p=0.017) and female gender (OR=2.2; 95%CI=1.02-4.97; p=0.045) were independent predictors of better responses to quality of life, anxiety and acceptance of the ICD, respectively. Conclusion The identification of predictors for better quality of life scores, anxiety, and acceptance of the device can support the implementation of specific care for patients with a greater chance of presenting unfavorable results.

How we do it: Cardiac implantable devices are not a contraindication to MRI: time for a paradigm shift.

Magnetic resonance imaging (MRI) is now an indispensable diagnostic tool in medicine due to its outstanding contrast resolution and absence of radiation exposure, enabling detailed tissue characterization and three-dimensional anatomical representation. This is especially important when evaluating individuals with congenital heart disease (CHD) who frequently require cardiac implantable electrical devices (CIEDs). While MRI safety issues have previously limited its use in patients with CIEDs, new advances have called these limitations into question. However, difficulties persist in the pediatric population due to the continued lack of specific safety data both related to imaging young children and the specific CIED devices they often require. This paper discusses MRI safety considerations related to imaging patients with CIEDs, investigates pediatric-specific problems, and describes thorough methods for safe MRI access, highlighting the significance of specialized institutional guidelines.

The Paradigm of Sudden Death Prevention in Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a relatively common and, often, inherited cardiac disease, once regarded as largely untreatable with ominous prognosis and, perhaps, most visibly as a common cause of sudden cardiac death (SCD) in the young. However, HCM is now more accurately considered a treatable disease with management options that significantly alter its clinical course. This is particularly true for SCD because the penetration of implantable cardioverter-defibrillators into HCM practice enables primary prevention device therapy that reliably terminates potentially lethal ventricular tachyarrhythmias (3% to 4%/year). This therapeutic advance is largely responsible for >10-fold decrease in the overall disease-related mortality to 0.5%/year, independent of patient age. A guideline-based clinical risk stratification algorithm has evolved, which included variables identifiable with cardiac magnetic resonance: ≥1 risk markers judged major within the clinical profile of an individual patient, associated with a measure of physician judgment and shared decision-making, can be sufficient to consider the recommendation of a prophylactic defibrillator implant. Implantable cardioverter-defibrillator decisions using the American College of Cardiology and the American Heart Association traditional major risk marker strategy are associated with a 95% sensitivity for identifying those patients who subsequently experience appropriate therapy, albeit often 5 to 10+ years after implant but without heart failure deterioration or death after a device intervention. A mathematical SCD risk score proposed by European Society of Cardiology is associated with a relatively low sensitivity (33%) for predicting and preventing SCD events but with potential for less device overtreatment.

Predicting worsening heart failure hospitalizations in patients with implantable cardioverter defibrillators: is it all about alerts? A pooled analysis of nine trials.

AIMS: To predict worsening heart failure hospitalizations (WHFHs) in patients with implantable defibrillators and remote monitoring, the HeartInsight algorithm (Biotronik, Berlin, Germany) calculates a heart failure (HF) score combining seven physiologic parameters: 24 h heart rate (HR), nocturnal HR, HR variability, atrial tachyarrhythmia, ventricular extrasystoles, patient activity, and thoracic impedance. We compared temporal trends of the HF score and its components 12 weeks before a WHFH with 12-week trends in patients without WHFH, to assess whether trends indicate deteriorating HF regardless of alert status. METHODS AND RESULTS: Data from nine clinical trials were pooled, including 2050 patients with a defibrillator capable of atrial sensing, ejection fraction ≤ 35%, NYHA class II/III, no long-standing atrial fibrillation, and 369 WHFH from 259 patients. The mean HF score was higher in the WHFH group than in the no WHFH group (42.3 ± 26.1 vs. 30.7 ± 20.6, P < 0.001) already at the beginning of 12 weeks. The mean HF score further increased to 51.6 ± 26.8 until WHFH (+22% vs. no WHFH group, P = 0.003). As compared to the no WHFH group, the algorithm components either were already higher 12 weeks before WHFH (24 h HR, HR variability, thoracic impedance) or significantly increased until WHFH (nocturnal HR, atrial tachyarrhythmia, ventricular extrasystoles, patient activity). CONCLUSION: The HF score was significantly higher at, and further increased during 12 weeks before WHFH, as compared to the no WHFH group, with seven components showing different behaviour and contribution. Temporal trends of HF score may serve as a quantitative estimate of HF condition and evolution prior to WHFH.

Perioperative management of patients with cardiac implantable electronic devices.

The use of cardiac implantable electronic devices (CIEDs) has increased significantly in recent years. Consequently, more patients with CIEDs will undergo surgery during their lifetime, and thus the involvement of anesthesiologists in the perioperative management of CIEDs is increasing. With ongoing advancements in technology, many types of CIEDs have been developed, including permanent pacemakers, leadless pacemakers, implantable cardioverter defibrillators, cardiac resynchronization therapy-pacemakers/defibrillators, and implantable loop recorders. The functioning of CIEDs exposed to an electromagnetic field can be affected by electromagnetic interference, potential sources of which can be found in the operating room. Thus, to prevent potential adverse events caused by electromagnetic interference in the operating room, anesthesiologists must have knowledge of CIEDs and be able to identify each type. This review focuses on the perioperative management of patients with CIEDs, including indications for CIED implantation to determine the baseline cardiovascular status of patients; concerns associated with CIEDs before and during surgery; perioperative management of CIEDs, including magnet application and device reprogramming; and additional perioperative provisions for patients with CIEDs. As issues such as variations in programming capabilities and responses to magnet application according to device can be challenging, this review provides essential information for the safe perioperative management of patients with CIEDs.

Preditores de Terapias Apropriadas e Óbito em Pacientes com Cardiodesfibrilador Implantável e Cardiopatia Chagásica Crônica / Predictors of Appropriate Therapies and Death in Patients with Implantable Cardioverter-Defibrillator and Chronic Chagas Heart Disease

Resumo Fundamento: Existem poucos estudos retrospectivos e prospectivos sobre cardiodesfibrilador implantável (CDI) na prevenção primária e secundária de morte súbita na cardiopatia chagásica crônica (CCC). Objetivos: Descrever a evolução a longo prazo dos portadores de CCC com CDI e identificar e analisar os preditores de mortalidade e de terapia apropriada do dispositivo nessa população. Métodos: Trata-se de um estudo prospectivo histórico com 117 pacientes portadores de CDI e CCC. Dispositivos foram implantados de janeiro de 2003 a dezembro de 2021. Fatores preditores de terapias apropriadas e mortalidade a longo prazo foram identificados e analisados. O nível de significância estatística é de p < 0,05. Resultados: Pacientes (n = 117) tiveram mediana de seguimento de 61 meses (25 a 121 meses), sendo o gênero masculino (74%) predominante e a mediana de idade de 55 anos (48 a 64 anos). Houve 43,6% de choques apropriados, 26,5% de estimulação cardíaca antitaquicardia (ATP) e 51% de terapias apropriadas. Durante o seguimento, 46 pacientes (39,7%) foram a óbito. A mortalidade foi de 6,2% pessoas-ano (intervalo de confiança [IC] 95%: 4,6 a 8,3), com 2 mortes súbitas durante o seguimento. A prevenção secundária (hazard ratio [HR] 2.1; IC 95%: 1,1 a 4,3; p = 0,029) e a fração de ejeção menor que 30% (HR 1.8; IC 95%: 1,1 a 3,1; p < 0,05) foram preditores de terapias apropriadas. Escore de Rassi intermediário apresentou uma forte associação com ocorrência de ATP isoladamente (p = 0,015). A classe funcional IV (p = 0,007), fração de ejeção do ventrículo esquerdo < 30 (p = 0,010) e a idade maior que 75 anos (p = 0,042) foram preditores de mortalidade total. Conclusão: Os desfibriladores na CCC apresentaram elevada incidência de acionamento apropriado especialmente naqueles pacientes de prevenção secundária, fração de ejeção do ventrículo esquerdo baixa e escore de Rassi intermediário. Os pacientes com insuficiência cardíaca congestiva, classe funcional avançada e idade maior que 75 anos apresentaram elevada mortalidade.

Abstract Background: There are few retrospective and prospective studies on implantable cardioverter-defibrillators (ICD) in primary and secondary prevention of sudden death in chronic Chagas heart disease (CCHD). Objectives: To describe the long-term evolution of patients with CCHD and ICD and to identify and analyze predictors of mortality and appropriate device therapy in this population. Methods: This was a historical prospective study with 117 patients with ICD and CCHD. Devices were implanted from January 2003 to December 2021. Predictors of appropriate therapies and long-term mortality were identified and analyzed. The level of statistical significance was p < 0.05. Results: Patients (n = 117) had a median follow-up of 61 months (25 to 121 months); they were predominantly male (74%), with a median age of 55 years (48 to 64 years). There were 43.6% appropriate shocks, 26.5% antitachycardia pacing (ATP), and 51% appropriate therapies. During follow-up, 46 patients (39.7%) died. Mortality was 6.2% person-years (95% confidence interval [CI]: 4.6 to 8.3), with 2 sudden deaths during follow-up. Secondary prevention (hazard ratio [HR] 2.1; 95% CI: 1.1 to 4.3; p = 0.029) and ejection fraction less than 30% (HR 1.8; 95% CI: 1.1 to 3.1; p < 0.05) were predictors of appropriate therapies. Intermediate Rassi score showed a strong association with the occurrence of ATP alone (p = 0.015). Functional class IV (p = 0.007), left ventricular ejection fraction < 30 (p = 0.010), and age above 75 years (p = 0.042) were predictors of total mortality. Conclusion: ICDs in CCHD showed a high incidence of appropriate activation, especially in patients with secondary prevention, low left ventricular ejection fraction, and intermediate Rassi score. Patients with congestive heart failure, elevated functional class, and age over 75 years showed elevated mortality.

[Legal aspects of telemedicine in cardiology in Germany]. / Rechtliche Aspekte der Telemedizin in der Kardiologie in Deutschland.

Since 2016, quarterly telemedical remote monitoring of patients with an implanted defibrillator or cardiac resynchronization therapy (CRT) system is part of the Einheitlichen Bewertungsmaßstab (EBM, physician's fee schedule) and is the first telemedical service to be reimbursed in German cardiology. Many publications like the TIM-HF2 or the InTime trial have shown a significant benefit for different endpoints in patients with advanced heart failure. Therefore, the German Society of Cardiology (DGK) has published different recommendations that emphasize an obvious indication of telemedical care with daily control of implantable cardioverter-defibrillator (ICD) information, parameters like blood pressure and weight, and telemedical counselling of patients with heart failure with reduced ejection fraction. This recommendation is also part of the guidelines of the European Society of Cardiology (ESC) published in 2021. It has a level IIb for patients with heart failure. In December 2020 the "Gemeinsame Bundesausschuss" (G-BA) decided to accept telemonitoring as a diagnostic tool and treatment option for patients with heart failure. This service of physicians became part of the EBM and ever since may be offered to patients. This development is accompanied with many questions regarding a physician's accountability, protection of data privacy, and also regarding the structures given by the G­BA and the "Kassenärztlichen Vereinigungen" (KV). Thus, this paper tries to give an overview of these topics. It will also provide a critical discussion of these structures and their legal foundation because there are many constraints that need to be taken into consideration as a cardiologist. These constraints may ultimately hinder the expansion of this service to patients in Germany.

Postapproval Study of a Subcutaneous Implantable Cardioverter-Defibrillator System.

BACKGROUND: The subcutaneous implantable cardioverter-defibrillator (S-ICD) was developed to avoid complications related to transvenous implantable cardioverter-defibrillator (TV-ICD) leads. Device safety and efficacy were demonstrated previously with atypical clinical patients or limited follow-up. OBJECTIVES: The S-ICD PAS (Subcutaneous Implantable Cardioverter-Defibrillator System Post Approval Study) is a real-world, multicenter, registry of U.S. centers that was designed to assess long-term S-ICD safety and efficacy in a diverse group of patients and implantation centers. METHODS: Patients were enrolled in 86 U.S. centers with standard S-ICD indications and were observed for up to 5 years. Efficacy endpoints were first and final shock efficacy. Safety endpoints were complications directly related to the S-ICD system or implantation procedure. Endpoints were assessed using prespecified performance goals. RESULTS: A total of 1,643 patients were prospectively enrolled, with a median follow-up of 4.2 years. All prespecified safety and efficacy endpoint goals were met. Shock efficacy rates for discrete episodes of ventricular tachycardia or ventricular fibrillation were 98.4%, and they did not differ significantly across follow-up years (P = 0.68). S-ICD-related and electrode-related complication-free rates were 93.4% and 99.3%, respectively. Only 1.6% of patients had their devices replaced by a TV-ICD for a pacing need. Cumulative all-cause mortality was 21.7%. CONCLUSIONS: In the largest prospective study of the S-ICD to date, all study endpoints were met, despite a cohort with more comorbidities than in most previous trials. Complication rates were low and shock efficacy was high. These results demonstrate the 5-year S-ICD safety and efficacy for a large, diverse cohort of S-ICD recipients. (Subcutaneous Implantable Cardioverter-Defibrillator [S-ICD] System Post Approval Study [PAS]; NCT01736618).

Spanish Rhythm Association member´s perspectives on cardiac implantable electronic device reuse in low- and middle-income countries.

BACKGROUND: Postmortem explanted cardiac implantable electronic devices (CIEDs) from developed countries could provide patients unable to afford new devices in low- and middle-income countries (LMIC) a treatment they lack. This study describes the preferences of electrophysiologists and device implanting cardiologists from Spain on the management of explanted CIEDs and opinions and concerns regarding reuse in LMIC. METHODS: A nationwide self-administered questionnaire was sent to members of the Spanish Rhythm Association (n = 1110), between December 2020 and January 2021. RESULTS: Forty-two physician responses were obtained (response rate 5%). There was a strong preference to donate explanted devices for reuse in humans (61.9%) or animals (31%). The vast majority of the participants thought device reutilization was safe, ethical, and a reasonable alternative if a new device is not accessible. Moreover, they indicated they would be comfortable asking patients to consider post-mortem donation, and willing to implant post-mortem explanted and resterilized devices if they were unable to obtain new ones. 57.1% of respondents considered it would be beneficial for patients to have a document so they could reflect their wishes regarding device handling after their death. The most mentioned concerns regarding device reuse were malfunction (57.1%) and infection (54.8%). CONCLUSIONS: The majority of respondents support reusable CIED donation to LMIC. It would be interesting to study the feasibility of a nationwide device reutilization program.

Estratégias Percutâneas em Doenças Estruturais: Foco em Insuficiência Cardíaca Crônica / Percutaneous Strategies in Structural Heart Diseases: Focus on Chronic Heart Failure

Resumo As inovações em dispositivos ao longo das últimas décadas proporcionaram uma melhora no diagnóstico e tratamento de pacientes com insuficiência cardíaca. Essas novas ferramentas progressivamente adaptaram-se a estratégias minimamente invasivas e as opções percutâneas multiplicaram-se de forma rápida. No presente artigo revisamos as direções atuais e futuras dos dispositivos utilizados como opções adjuvantes para o diagnóstico e tratamento adjuvante na insuficiência cardíaca crônica, o seu desenvolvimento, mecanismos e estudos mais recentes

Abstract Innovations in devices during the last decade contributed to enhanced diagnosis and treatment of patients with cardiac insufficiency. These tools progressively adapted to minimally invasive strategies with rapid, widespread use. The present article focuses on actual and future directions of device-related diagnosis and treatment of chronic heart failure.

Current evidence of ultrasound-guided fascial plane blocks for cardiac surgery: a narrative literature review.

Fascial plane blocks are useful for multimodal analgesia after cardiac surgery since they can provide effective analgesia without the serious risks associated with conventional techniques such as neuraxial hematoma and pneumothorax. This narrative review covers blocks performed at the parasternal intercostal, interpectoral, pectoserratus, serratus anterior, erector spinae, and retrolaminar planes, which are targets for fascial plane blocks in cardiac surgery. Brief anatomical considerations, mechanisms, and currently available evidence are reviewed. Additionally, recent evidence on fascial plane blocks for subcutaneous-implantable cardioverter-defibrillator implantation are also reviewed.

Inadvertent Intraoperative Defibrillation Secondary to Electrocautery Grounding Pad Placement.

Intraoperative defibrillation secondary to the usage of electrocautery in a patient with a cardiovascular implantable electronic device is a rare occurrence, and below-the-umbilicus electrocautery use causing inadvertent defibrillation is a near-zero risk. Defibrillation secondary to electrodispersive pad (EDP) radiofrequency dispersion has only ever been theorized. In this report, we describe the case of a 67-year-old male with an automatic implantable cardioverter defibrillator (AICD) undergoing a robotic-assisted left anterior total hip arthroplasty for left hip osteoarthritis who experienced inadvertent intraoperative defibrillation concurrent with electrocautery usage. The defibrillations ceased following contralateral EDP repositioning and application of a donut magnet overlying the patient's AICD.

Detecting early physiologic changes through cardiac implantable electronic device data among patients with COVID-19.

Background: Cardiac implantable electronic devices (CIEDs) may enable early identification of COVID-19 to facilitate timelier intervention. Objective: To characterize early physiologic changes associated with the onset of acute COVID-19 infection, as well as during and after acute infection, among patients with CIEDs. Methods: CIED sensor data from March 2020 to February 2021 from 286 patients with a CIED were linked to clinical data from electronic health records. Three cohorts were created: known COVID-positive (n = 20), known COVID-negative (n = 166), and a COVID-untested control group (n = 100) included to account for testing bias. Associations between changes in CIED sensors from baseline (including HeartLogic index, a composite index predicting worsening heart failure) and COVID-19 status were evaluated using logistic regression models, Wilcoxon signed rank tests, and Mann-Whitney U tests. Results: Significant differences existed between the cohorts by race, ethnicity, CIED device type, and medical admissions. Several sensors changed earlier for COVID-positive vs COVID-negative patients: HeartLogic index (mean 16.4 vs 9.2 days [P = .08]), respiratory rate (mean 8.5 vs 3.9 days [P = .01], and activity (mean 8.2 vs 3.5 days [P = .008]). Respiratory rate during the 7 days before testing significantly predicted a positive vs negative COVID-19 test, adjusting for age, sex, race, and device type (odds ratio 2.31 [95% confidence interval 1.33-5.13]). Conclusion: Physiologic data from CIEDs could signal early signs of infection that precede clinical symptoms, which may be used to support early detection of infection to prevent decompensation in this at-risk population.

[A practical approach to device interrogation]. / Praktisches Vorgehen in der Schrittmachernachsorge.

For many cardiologists in training, interrogation of implantable cardiac devices is the first step into the fascinating world of electrophysiology. A growing number of patients implanted with pacemakers, implantable cardioverter-defibrillators (ICDs) or cardiac resynchronization therapy devices (CRTs) fuels the need for a basic understanding of those devices by every cardiologist. This article is meant to address the most important theoretical points to facilitate an easy, quick but still comprehensive device interrogation in nine steps.