Subcutaneous versus transvenous implantable cardioverter defibrillator in hypertrophic cardiomyopathy: a systematic review and meta-analysis.

Background: A subcutaneous implantable cardioverter-defibrillator (S-ICD) is an alternative to a transvenous implantable cardio defibrillator (TV-ICD). An S-ICD reduces the risk of transvenous lead placement. However, further research is required to determine how S-ICDs affect patients with hypertrophic cardiomyopathy (HCM). In this study, we investigated the comparative efficacy and safety of S-ICDs versus TV-ICDs in HCM. Methods: On December 6th, 2023, we performed a comprehensive search of the PubMed, Embase, Scopus, and Cochrane databases to identify randomized clinical trials (RCTs) and observational studies comparing S-ICDs with TV-ICDs in HCM patients published from 2004 until 2023. No language restrictions were applied. The primary outcome was appropriate shocks (AS), with inappropriate shocks (IAS), and device-related complications considered as secondary outcomes. Odds ratios (ORs) and 95% confidence intervals (CIs) were pooled using a random effects model. The ROBINS-I tool was used to assess the risk of bias of the studies. Results: The search yielded 1,114 records. Seven studies comprising 4,347 HCM patients were included, of whom 3,325 (76.0%) had TV-ICDs, and 1,022 (22.6%) had S-ICDs. There were 2,564 males (58.9%). The age range was from 39.1 to 49.4 years. Compared with the TV-ICD group, the S-ICD cohort had a significantly lower incidence of device-related complications (OR 0.52; 95% CI: 0.30-0.89; P=0.02; I2=4%). Contrastingly, there were no statistically significant differences in the occurrences of AS (OR 0.49; 95% CI: 0.22-1.08; P=0.08; I2=75%) and IAS (OR 1.03; 95% CI: 0.57-1.84; P=0.93; I2=65%) between the two device modalities. In the analysis of the overall risk of bias in the studies, we found 42% of them with several, 28% with moderate, and 14% with low risk of bias. Conclusions: In HCM patients, S-ICDs were associated with a lower incidence of device-associated problems than TV-ICDs. AS and IAS incidence rates were similar between groups. These findings may assist clinicians in determining the most suitable device for treating patients with HCM.

Ventricular predominance in biventricular arrhythmogenic cardiomyopathy: Should new subtype criteria be recognized?

Arrhythmogenic cardiomyopathy is a biventricular disease in which the effect on the left ventricle can be either equivalent to or more severe than that on the right ventricle. It is a rare disease due to its low reported prevalence and typically becomes clinically evident during the second to fourth decade of life. It represents 4% of sudden cardiac death cases referred for autopsy and 10% of cases of unexplained cardiac arrest. We present a challenging case report of a 68-year-old man who arrived at the emergency room with chest discomfort, palpitations, and light-headedness before a syncopal episode with urinary incontinence. During monitoring, ventricular tachycardia was detected and was treated with cardioversion. However, a follow-up electrocardiogram revealed low QRS voltages in limb leads and T-wave inversion in the left precordial leads. The patient underwent a transthoracic echocardiogram and a gadolinium-based magnetic resonance imaging study to evaluate the possibility of acute decompensated heart failure. Both imaging studies revealed low ejection fraction and systolic dysfunction in both right and left ventricles. Furthermore, in the late gadolinium enhancement study, extensive left ventricular subepicardial enhancement with septal predominance in a ring pattern and an irregular morphology of the right ventricular free wall were observed. A diagnosis of biventricular arrhythmogenic cardiomyopathy was established based on the 2020 Padua Criteria. Although there is not a recognized classification within these criteria to establish its subtype, in our case there was a left ventricular predominance due to the presence of additional left ventricular categories.

Inter-American Society of Cardiology (CIFACAH-ELECTROSIAC) and Latin-American Heart Rhythm Society (LAHRS): multidisciplinary review on the appropriate use of implantable cardiodefibrillator in heart failure with reduced ejection fraction.

BACKGROUND: Our main objective was to present a multidisciplinary review on the epidemiology of sudden cardiac death (SCD) and the tools that could be used to identify malignant ventricular arrhythmias (VAs) and to perform risk stratification. In addition, indications and contraindications for the use of implantable cardioverter defibrillator (ICD) in general and in special populations including the elderly and patients with chronic kidney disease (CKD) are also given. METHODS: An expert group from the Inter American Society of Cardiology (IASC), through their HF Council (CIFACAH) and Electrocardiology Council (ElectroSIAC), together with the Latin American Heart Rhythm Society (LAHRS), reviewed and discussed the literature regarding the appropriate use of an ICD in people with heart failure (HF) with reduced ejection fraction (HFpEF). Indications and contraindications for the use of ICD are presented in this multidisciplinary review. RESULTS: Numerous clinical studies have demonstrated the usefulness of ICD in both primary and secondary prevention of SCD in HFpEF. There are currently precise indications and contraindications for the use of these devices. CONCLUSIONS: In some Latin American countries, a low rate of implantation is correlated with low incomes, but this is not the case for all Latin America. Determinants of the low rates of ICD implantation in many Latin American countries are still a matter of research. VA remains one of the most common causes of cardiovascular death associated with HFrEF and different tools are available for stratifying the risk of SCD in this population.

Dispositivos cardíacos implantables y uso de resonancia magnética / Cardiac implantable devices and use of magnetic resonance / Dispositivos cardíacos implantáveis e utilização da ressonância magnética

El uso de la resonancia magnética (RM) en las distintas áreas de la medicina se ha expandido de manera significativa y de forma diaria se solicitan numerosos estudios. El hecho de que los resonadores pueden interaccionar con algunos objetos ha llevado a que históricamente se les niegue la realización de este estudio a pacientes portadores de dispositivos cardíacos porque se entiende que existen contraindicaciones absolutas. El avance de la tecnología de los dispositivos y la creciente evidencia publicada han cambiado este concepto. Nos proponemos revisar los mecanismos por los cuales un dispositivo implantable puede interactuar con el resonador y las implicancias clínicas que esto podría tener si las hubiera. La mayoría de los pacientes portadores de dispositivos cardíacos de estimulación podrán realizarse una RM, pero para que este procedimiento sea seguro es importante conocer las características y el tipo específico de dispositivo implantado. Proponemos finalmente puntos clave y algoritmos para tener en cuenta para el manejo adecuado de estos pacientes.

The use of magnetic resonance imaging (MRI) in different areas of medicine has expanded significantly and numerous procedures are indicated daily. The fact that resonators could interact with some objects has historically led to patients with cardiac devices being denied an MRI on the understanding that they suppose an absolute contraindication. Advances in device technology and the increasing evidence have changed this concept. We intend to review the mechanisms by which an implantable device could interact with the resonator and the clinical implications that this could have if any. Most patients will be able to undergo these studies, but to determine the safety of performing an MRI it is important to know the characteristics and specific type of implanted device. Finally, we provide key points and algorithms to take into account for these patients.

O uso da ressonância magnética em diferentes áreas da medicina tem se expandido significativamente e inúmeros exames são indicados diariamente. A possibilidade de que os ressonadores interajam com alguns objetos historicamente levou os pacientes com dispositivos cardíacos a terem a ressonância magnética negada por entender que existem contraindicações absolutas. Os avanços na tecnologia de dispositivos e o aumento das evidências publicadas mudaram esse conceito. Pretendemos revisar os mecanismos pelos quais um dispositivo implantável pode interagir com o ressonador e as implicações clínicas que isso pode ter, se houver. A grande maioria dos pacientes poderá se submeter a esses estudos, mas para determinar a segurança de realizar uma ressonância magnética é importante conhecer as características e o tipo específico de dispositivo implantado. Por fim, propomos pontos e algoritmos para a gestão dos pacientes.

Effect of ivabradine on ventricular arrhythmias in heart failure patients with reduced ejection fraction

SUMMARY BACKGROUND/INTRODUCTION: Heart failure patients with reduced ejection fraction are at high risk for ventricular arrhythmias and sudden cardiac death. Ivabradine, a specific inhibitor of the If current in the sinoatrial node, provides heart rate reduction in sinus rhythm and angina control in chronic coronary syndromes. OBJECTIVE: The effect of ivabradine on ventricular arrhythmias in heart failure patients with reduced ejection fraction patients has not been fully elucidated. The aim of this study was to investigate the effect of ivabradine use on life-threatening arrhythmias and long-term mortality in heart failure patients with reduced ejection fraction patients. METHODS: In this retrospective study, 1,639 patients with heart failure patients with reduced ejection fraction were included. Patients were divided into two groups: ivabradine users and nonusers. Patients presenting with ventricular tachycardia, the presence of ventricular extrasystole, and ventricular tachycardia in 24-h rhythm monitoring, appropriate implantable cardioverter-defibrillator shocks, and long-term mortality outcomes were evaluated according to ivabradine use. RESULTS: After adjustment for all possible variables, admission with ventricular tachycardia was three times higher in ivabradine nonusers (95% confidence interval 1.5-10.2). The presence of premature ventricular contractions and ventricular tachycardias in 24-h rhythm Holter monitoring was notably higher in ivabradine nonusers. According to the adjusted model for all variables, 4.1 times more appropriate implantable cardioverter-defibrillator shocks were observed in the ivabradine nonusers than the users (95%CI 1.8-9.6). Long-term mortality did not differ between these groups after adjustment for all covariates. CONCLUSION: The use of ivabradine reduced the appropriate implantable cardioverter-defibrillator discharge in heart failure patients with reduced ejection fraction patients. Ivabradine has potential in the treatment of ventricular arrhythmias in heart failure patients with reduced ejection fraction patients.

ICD indication in hypertrophic cardiomyopathy: which algorithm to use?

SUMMARY OBJECTIVE: This study aimed to evaluate the agreement in the indication of implantable cardioverter-defibrillators in patients with Hypertrophic cardiomyopathy, as per the 2014 European Society of Cardiology and 2020 American Heart Association recommendations, and evaluate fragmented QRS as a predictor of cardiovascular outcome. METHODS: Retrospective cohort with 81 patients was evaluated between 2019 and 2021. Patients with hypertrophic cardiomyopathy ≥16 years old were included. Exclusion criteria include secondary myocardiopathy and follow-up <1 year. Kappa coefficient was used to determine the agreement. Survival and incidence curves were determined by Kaplan-Meier method. A p<0.05 was considered significant. RESULTS: The fragmented QRS was identified in 44.4% of patients. There were no differences between patients with and without fragmented QRS regarding clinical parameters, echocardiography, fibrosis, and sudden cardiac death risk. During follow-up of 4.8±3.4 years, there was no sudden cardiac death, but 20.6% patients with implantable cardioverter-defibrillator had at least one appropriate shock. Three of the seven appropriate shocks occurred in European Society of Cardiology low- to moderate-risk patients. Three shocks occurred in moderate-risk patients and four in American Heart Association high-risk patients. Overall recommendations agreement was 64% with a kappa of 0.270 (p=0.007). C-statistic showed no differences regarding the incidence of appropriate shock (p=0.644). CONCLUSION: sudden cardiac death risk stratification algorithms present discrepancies in implantable cardioverter-defibrillator indication, both with low accuracy.

Remote monitoring of pacemakers and defibrillators: Effective and safe in Brazil?

Background: The remote monitoring (RM) of cardiac implantable electronic devices (CIEDs) has become a common method of in-home monitoring and follow-up in high-income countries given its effectiveness, safety, convenience, and the possibility of early intervention. However, in Brazil, RM is still underutilized. Objectives: This observational study aims to demonstrate our experience of using RM in Brazil and the predictive factors of RM of CIED follow-up in Brazil. Methods: This was a prospective cohort study of patients with a CIED. Event rates are reported and clinical responses to those findings and outcomes based on the detection of RM. A logistic regression model was performed to identify predictors of more events, with P < .05 for statistical significance. Results: This study evaluated consecutive 119 patients: 30.2% with pacemakers, 42.8% with implantable cardioverter-defibrillator, 22.7% with cardiac resynchronization therapy (CRT) with defibrillator, and 3.3% with CRT with pacemaker. Events were detected in 63.9% of the cases in 29.5 ± 23 months of follow-up. The outcomes found were that 44.5% needed elective evaluation in medical treatment and 23.5% needed immediate evaluation in therapy. Logistic regression analysis showed that the groups with CRT or CRT with defibrillator (75.0%), reduced ejection fraction (76.5%), and New York Heart Association functional class ≥II (75.0%) had the highest RM event rates. Conclusions: RM proved to be effective and safe in the follow-up of patients with CIEDs in Brazil, allowing early interventions and facilitating therapeutic management.

Efficacy and Complications of Subcutaneous versus Conventional Cardioverter Defibrillators: A Systematic Review and Meta-analysis.

BACKGROUND/OBJECTIVES: Implantable cardioverter defibrillators are used to prevent sudden cardiac death. The subcutaneous implantable cardioverter-defibrillator was newly developed to overcome the limitations of the conventional implantable cardioverter defibrillator-transvenous device. The subcutaneous implantable cardioverter defibrillator is indicated for young patients with heart disease, congenital heart defects, and poor venous access, who have an indication for implantable cardioverter defibrillator without the need for anti-bradycardic stimulation. We aimed to compare the efficacy and complications of subcutaneous with transvenous implantable cardioverter- defibrillator devices. METHODOLOGY: A systematic review was conducted using different databases. The inclusion criteria were observational and clinical randomized trials with no language limits and no publication date limit that compared subcutaneous with transvenous implantable cardioverter-defibrillators. The selected patients were aged > 18 years with complex ventricular arrhythmia. RESULTS: Five studies involving 2111 patients who underwent implantable cardioverter defibrillator implantation were included. The most frequent complication in the subcutaneous device group was infection, followed by hematoma formation and electrode migration. For the transvenous device, the most frequent complications were electrode migration and infection. Regarding efficacy, the total rates of appropriate shocks were 9.04% and 20.47% in the subcutaneous and transvenous device groups, respectively, whereas inappropriate shocks to the subcutaneous and transvenous device groups were 11,3% and 10,7%, respectively. CONCLUSION: When compared to the transvenous device, the subcutaneous device had lower complication rates owing to lead migration and less inappropriate shocks due to supraventricular tachycardia; nevertheless, infection rates and improper shocks due to T wave oversensing were comparable for both devices CRD42021251569.

Muerte súbita cardíaca por fibrilación ventricular asociada a isquemia miocárdica, tratada por desfibrilador automático implantable / Sudden cardiac death due to ventricular fibrillation associated with myocardial ischemia, treated by implantable cardioverter defibrillator

Resumen: Reportamos el caso de un hombre de 67 años, con múltiples factores de riesgo cardiovascular, quien en el año 2015 presentó muerte súbita por fibrilación ventricular sin lesiones coronarias significativas, tras lo cual se implantó un desfibrilador automático. En el año 2019 presentó un nuevo episodio de fibrilación ventricular en relación con síndrome coronario agudo con supradesnivel del ST localizado en pared anterior, registrado y adecuadamente resuelto por el dispositivo. Se demostró una oclusión aterotrombótica en la porción proximal de la arteria descendente anterior. Fue precoz y exitosamente manejado con angioplastía coronaria percutánea e implante de stent fármaco activo, guiado por tomografía por coherencia óptica intracoronaria. A las 48 horas post angioplastía, presentó episodio de taquicardia ventricular polimorfa reconocido y tratado por el cardiodesfibrilador, sin consecuencias. Electivamente se efectuó angioplastía e implante de stent metálico en arteria coronaria derecha distal, con buen resultado angiográfico. La posterior evolución del paciente fue satisfactoria, sin manifestaciones de insuficiencia cardíaca, angina ni arritmias.

Abstract: A 67-year-old man, with multiple cardiovascular risk factors who in 2015 presented sudden death due to ventricular fibrillation without significant coronary lesions, after which an implantable automatic defibrillator (ICD) was implanted. In 2019, he presented a new episode of ventricular fibrillation adequately resolved by the device, in relation to an acute coronary syndrome with ST elevation in the anterior wall of the left ventricle, due to atherothrombotic occlusion in the proximal portion of the anterior descending artery. He was early and successfully managed with percutaneous coronary angioplasty by the insertion of a drug eluting stent, implanted guided by intracoronary optical coherence tomography. Forty eight hours later, he presented an episode polymorphic ventricular tachycardia recognized and treated by the ICD. Angioplasty with a bare metal stent implantation were performed in the distal right coronary artery, with good angiographic results. The subsequent course was satisfactory, with no manifestations of heart failure, angina or arrhythmias.

Renal denervation for the treatment of ventricular arrhythmias: A systematic review and meta-analysis.

INTRODUCTION: Ventricular arrhythmias (VAs) are a major cause of morbidity and mortality in patients with heart disease. Recent studies evaluated the effect of renal denervation (RDN) on the occurrence of VAs. We conducted a systematic review and meta-analysis to determine the efficacy and safety of this procedure. METHODS AND RESULTS: A systematic search of the literature was performed to identify studies that evaluated the use of RDN for the management of VAs. Primary outcomes were reduction in the number of VAs and implantable cardioverter-defibrillator (ICD) therapies. Secondary outcomes were changes in blood pressure and renal function. Ten studies (152 patients) were included in the meta-analysis. RDN was associated with a reduction in the number of VAs, antitachycardia pacing, ICD shocks, and overall ICD therapies of 3.53 events/patient/month (95% confidence interval [CI] = -5.48 to -1.57), 2.86 events/patient/month (95% CI = -4.09 to -1.63), 2.04 events/patient/month (95% CI = -2.12 to -1.97), and 2.68 events/patient/month (95% CI = -3.58 to -1.78), respectively. Periprocedural adverse events occurred in 1.23% of patients and no significant changes were seen in blood pressure or renal function. CONCLUSIONS: In patients with refractory VAs, RDN was associated with a reduction in the number of VAs and ICD therapies, and was shown to be a safe procedure.

Insights from the axillary vein puncture guided by ultrasound versus cephalic vein dissection trial.

Axillary vein puncture guided by ultrasound (US-Ax) versus cephalic vein dissection in pacemaker and defibrillator implant: a multicenter randomized clinical trial is a recently published study in which 88 patients were randomized in a 1:1 fashion to one of the two methods. Even being performed by operators with not previous ultrasound-guided axillary vein puncture experience, this group presented a higher success rate, lower procedural time and comparable complication incidence.

Lay abstract Recently a study evaluating two different approaches to cardiac devices implant was published. In the study, 88 patients were assigned to one of two methods for this procedure. The operators had no previous experience in one of the methods, but it demonstrated a higher success rate, took less time and had the same number of complications as the method the doctors had experience in. This paper evaluated the study and discusses what changes might take place in clinics as a result of these findings.

Advanced management of ventricular arrhythmias in chronic Chagas cardiomyopathy.

Chagas cardiomyopathy is a parasitic infection caused by Trypanosoma cruzi. Structural and functional abnormalities are the result of direct myocardial damage by the parasite, immunological reactions, dysautonomia, and microvascular alterations. Chronic Chagas cardiomyopathy (CCC) is the most serious and important manifestation of the disease, affecting up to 30% of patients in the chronic phase. It results in heart failure, arrhythmias, thromboembolism, and sudden cardiac death. As in other cardiomyopathies, scar-related reentry frequently results in ventricular tachycardia (VT). The scars typically are located in the inferior and lateral aspects of the left ventricle close to the mitral annulus extending from endocardium to epicardium. The scars may be more prominent in the epicardium than in the endocardium, so epicardial mapping and ablation frequently are required. Identification of late potentials during sinus rhythm and mid-diastolic potentials during hemodynamically tolerated VT are the main targets for ablation. High-density mapping during sinus rhythm can identify late isochronal regions that are then targeted for ablation. Preablation cardiac magnetic resonance imaging with late enhancement can identify potentials areas of arrhythmogenesis. Therapeutic alternatives for VT management include antiarrhythmic drugs and modulation of the cardiac autonomic nervous system.

Permanent pacemaker placement following valve surgery is not independently associated with worse outcomes.

Background: Permanent pacemaker placement (PPM) is associated with morbidity following cardiac surgery. This study identified associations between PPM placement and 5-year outcomes for patients that require PPM following valvular surgery. Methods: All patients who underwent valvular surgery at our medical center from 2011 to 2018 were considered for analysis. Multivariable analysis identified associations between PPM placement, mortality, and readmissions. Primary outcomes were operative complications and mortality. Secondary outcomes included 5-year survival and readmission. Results: A total of 175 (4.86%) of 3602 valvular surgery patients required postoperative PPM. The PPM cohort had significantly worse baseline comorbidities, including greater Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) scores (3.8 vs 2.4 P < .0001). The PPM cohort had greater rates of blood product transfusion, prolonged ventilation, and new-onset atrial fibrillation. PPM placement was significantly associated with third-degree heart block (5.26; 95% confidence interval [95% CI], 1.00-27.53; P = .0496), ventricular fibrillation/tachycardia (3.90; 95% CI, 1.59-9.59; P = .01), and atrial fibrillation/flutter (1.53; 95% CI, 1.05-2.24; P = .03). On Kaplan-Meier estimates, 5-year survival (68.8% vs 83.1%; P = 01) was significantly reduced in the PPM cohort. Five-year all-cause readmission (60.4% vs 50.04%; P = .01) and heart failure readmission (35.5% vs 20.1%; P < .000) occurred more frequently in the PPM cohort. On multivariable Cox regression analysis, PPM placement (hazard ratio, 1.12; 95% CI, 0.84-1.50; P = .444) was not an independent predictor of mortality. On competing risk analysis, PPM (hazard ratio, 1.33; 95% CI, 0.99-1.80; P = .062) was not a predictor of hospital readmission. Conclusions: Valvular surgery patients who required postoperative PPM had elevated baseline operative risk. However, PPM implantation was not associated with mortality or readmission.

Implantable cardioverter-defibrillator prevents sudden death in patients with Chagas cardiomyopathy in the Brazilian Amazon

Abstract Chagas disease (CD), with approximately 10,000 deaths annually, has become a worldwide health problem. Approximately 35% of cases may show cardiac manifestations such as arrhythmias and/or conduction disorders, heart failure, thromboembolic accidents, and sudden death. The Amazon region has long been considered a non-endemic area for CD; however, in the last decades, with an increase in the number of acute and chronic cases, disease evolution has received greater attention. Here, we report the successful implementation of a cardioverter-defibrillator for the prevention of sudden death in a patient with autochthonous Chagas cardiomyopathy in the Brazilian Amazon.

Sacubitril/Valsartan and Sudden Cardiac Death According to Implantable Cardioverter-Defibrillator Use and Heart Failure Cause: A PARADIGM-HF Analysis.

OBJECTIVES: The purpose of this study was to investigate the effect of sacubitril/valsartan therapy on sudden cardiac death (SCD) according to the use of and eligibility for an implantable cardioverter-defibrillator (ICD), stratified by heart failure cause. BACKGROUND: SCD still accounts for a significant proportion of overall mortality in heart failure with reduced ejection fraction (HFrEF). METHODS: Patients enrolled in the PARADIGM-HF (Prospective Comparison of ARNI with an ACE-Inhibitor to Determine Impact on Global Mortality and Morbidity in Heart Failure) trial (n = 8,399) were evaluated to assess patterns of ICD implantation and eligibility according to clinical guidelines. The impact of ICD (adjusted for propensity of ICD implantation) and sacubitril/valsartan therapy on SCD was evaluated by using cause-specific Cox models and competing risk analysis. RESULTS: At baseline, of the 7,145 patients (85%) eligible for ICD implantation, only 1,243 (15%) had an ICD. Use of ICD varied by region with the highest rates in North America (56%) and lowest in Asia-Pacific (1.7%). In a propensity score-adjusted analysis, use of an ICD was associated with a 56% lower risk of SCD in ICD-eligible patients, in both patients with ischemic (p < 0.001) and nonischemic cardiomyopathy (p = 0.02). Sacubitril/valsartan reduced SCD risk in patients with an ICD (hazard ratio [HR]: 0.49; 95% confidence interval [CI]: 0.25 to 0.99) and in those who were eligible for but did not receive an ICD (HR: 0.81; 95% CI: 0.67 to 0.98). This effect was particularly evident in nonischemic cardiomyopathy (p < 0.05), although interaction with the cause of HF was not significant (p = 0.11 in subjects using an ICD and p = 0.25 in eligible nonusers). CONCLUSIONS: Use of an ICD was associated with lower rates of SCD, regardless of HF cause but was underused in most regions of the world in the PARADIGM-HF study. Sacubitril/valsartan reduced SCD risk regardless of use of an ICD or eligibility, particularly in ICD users and nonischemic cardiomyopathy.

Seguimiento del paciente con cardiodesfibrilador automático implantable / Follow-up of the patient with automatic implantable cardioverter-defibrillator

RESUMEN Introducción: Los cardiodesfibriladores mejoran la supervivencia de los pacientes con riesgo de muerte súbita cardíaca. Existen escasos datos en nuestro país acerca de su eficacia en el seguimiento. Objetivo: Describir la evolución en el seguimiento de los pacientes con primoimplante de un cardiodesfibrilador automático. Método: Estudio ambispectivo, longitudinal, en 47 pacientes con primoimplante de un cardiodesfibrilador en el período septiembre de 2007 a diciembre de 2016, con cierre el 31 de diciembre de 2017. La probabilidad acumulada de supervivencia se estimó a través de las curvas de Kaplan-Meier. Resultados: La edad media fue de 57 ± 14,6 años, con predominio del sexo masculino (74,5%) y la indicación en prevención secundaria (83%). Presentaron terapias apropiadas el 57,4% de los pacientes, terapias inapropiadas un 23,4%, proarritmia del cardiodesfibrilador un 14,9% y tormenta arrítmica el 12,8% de los pacientes. Las terapias apropiadas se relacionaron con la fracción de eyección ≤ 35% (p=0,022) y la edad (p=0,031). La supervivencia acumulada libre del primer evento a los cuatro años fue 34,7%. La mortalidad cardiovascular se relacionó con: existencia de cardiopatía estructural (p=0,044), fracción de eyección ≤ 35% (p<0,001), clase funcional III-IV (p=0,046), terapias apropiadas (p=0,014) y tormenta arrítmica (p=0,002). La supervivencia acumulada libre de mortalidad cardiovascular fue de 70,7% al cuarto año. Conclusiones: La supervivencia de los pacientes con cardiodesfibrilador es buena. La mortalidad se asocia a un mayor deterioro del estado cardiovascular y a las terapias del dispositivo.

ABSTRACT Introduction: Implantable cardioverter-defibrillators improve the survival of patients at risk of sudden cardiac death. There is relatively little data in our country about their follow-up effectiveness. Objective: To describe the outcome of patients with primo-implantation of an automatic cardioverter-defibrillator during follow-up. Methods: An ambispective longitudinal cohort study was conducted in 47 patients with primo-implantation of a cardioverter-defibrillator in the period September 2007 to December 2016, ending on December 31, 2017. The cumulative probability of survival was estimated through the Kaplan-Meier curves. Results: Mean age was 57 ± 14.6 years, with male predominance (74.5%) and indication in secondary prevention (83%). Adequate therapies were found in 57.4% of patients, inadequate therapies in 23.4%, implantable cardioverter-defibrillator proarrhythmia in 14.9% and arrhythmic storm in 12.8% of patients. Adequate therapies were related to an ejection fraction ≤ 35% (p=0.022) and age (p=0.031). Cumulative free survival from the first event at four years was 34,7%. Cardiovascular mortality was related to: existence of structural heart disease (p=0.044), ejection fraction ≤ 35% (p<0.001), functional class III-IV (p=0.046), adequate therapies (p=0.014) and arrhythmic storm (p=0.002). Cumulative free survival of cardiovascular mortality was 70.7% at the fourth year. Conclusions: The survival of patients with implantable cardioverter-defibrillator is satisfactory. Mortality is associated with further deterioration of cardiovascular status and with device therapies.

Spectral Analysis and Mutual Information Estimation of Left and Right Intracardiac Electrograms during Ventricular Fibrillation.

Ventricular fibrillation (VF) signals are characterized by highly volatile and erratic electrical impulses, the analysis of which is difficult given the complex behavior of the heart rhythms in the left (LV) and right ventricles (RV), as sometimes shown in intracardiac recorded Electrograms (EGM). However, there are few studies that analyze VF in humans according to the simultaneous behavior of heart signals in the two ventricles. The objective of this work was to perform a spectral and a non-linear analysis of the recordings of 22 patients with Congestive Heart Failure (CHF) and clinical indication for a cardiac resynchronization device, simultaneously obtained in LV and RV during induced VF in patients with a Biventricular Implantable Cardioverter Defibrillator (BICD) Contak Renewal IVTM (Boston Sci.). The Fourier Transform was used to identify the spectral content of the first six seconds of signals recorded in the RV and LV simultaneously. In addition, measurements that were based on Information Theory were scrutinized, including Entropy and Mutual Information. The results showed that in most patients the spectral envelopes of the EGM sources of RV and LV were complex, different, and with several frequency peaks. In addition, the Dominant Frequency (DF) in the LV was higher than in the RV, while the Organization Index (OI) had the opposite trend. The entropy measurements were more regular in the RV than in the LV, thus supporting the spectral findings. We can conclude that basic stochastic processing techniques should be scrutinized with caution and from basic to elaborated techniques, but they can provide us with useful information on the biosignals from both ventricles during VF.

[Anesthetic management in a patient with arrhythmogenic right ventricular cardiomyopathy and an implantable cardioverter defibrillator: a case report]. / Anestesia para paciente com cardiomiopatia arritmogênica do ventrículo direito portador de cardioversor desfibrilador implantável: descrição de caso.

BACKGROUND AND OBJECTIVES: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic cardiomyopathy characterized by potentially lethal ventricular tachycardia. Here we describe a patient with ARVC and an Implantable Cardioverter Defibrillator (ICD) in whom maxillary sinus surgery was performed under general anesthesia. CASE REPORT: The patient was a 59 year-old man who was scheduled to undergo maxillary sinus surgery under general anesthesia. He had been diagnosed as having ARVC 15 years earlier and had undergone implantation of an ICD in the same year. Electrocardiography showed an epsilon wave in leads II, aVR, and V1-V3. Cardiac function was within normal range on transthoracic echocardiography. The ICD was temporarily deactivated after the patient arrived in the operating room and an intravenous line was secured. An external defibrillator was kept on hand for immediate defibrillation if any electrocardiographic abnormality was detected. Remifentanil 0.3 µg/kg/min, fentanyl 0.1 mg, propofol 154 mg, and rocuronium 46 mg were administered for induction of anesthesia. Tracheal intubation was performed orally. Anesthesia was maintained oxygen 1.0 L.min-1, air 2.0 L.min-1, propofol 5.0-7.0 mg.kg-1.h-1, and remifentanil 0.1-0.25 µg.kg-1.min-1. The surgery was completed as scheduled and the ICD was reactivated. The patient was then extubated after administration of sugammadex 200 mg. CONCLUSION: We report the successful management of anesthesia without lethal arrhythmia in a patient with ARVC and an ICD. An adequate amount of analgesia should be administered during general anesthesia to maintain adequate anesthetic depth and to avoid stress and pain.

Anesthetic management in a patient with arrhythmogenic right ventricular cardiomyopathy and an implantable cardioverter defibrillator: a case report / Anestesia para paciente com cardiomiopatia arritmogênica do ventrículo direito portador de cardioversor desfibrilador implantável: descrição de caso

Abstract Background and objectives: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic cardiomyopathy characterized by potentially lethal ventricular tachycardia. Here we describe a patient with ARVC and an Implantable Cardioverter Defibrillator (ICD) in whom maxillary sinus surgery was performed under general anesthesia. Case report: The patient was a 59 year-old man who was scheduled to undergo maxillary sinus surgery under general anesthesia. He had been diagnosed as having ARVC 15 years earlier and had undergone implantation of an ICD in the same year. Electrocardiography showed an epsilon wave in leads II, aVR, and V1-V3. Cardiac function was within normal range on transthoracic echocardiography. The ICD was temporarily deactivated after the patient arrived in the operating room and an intravenous line was secured. An external defibrillator was kept on hand for immediate defibrillation if any electrocardiographic abnormality was detected. Remifentanil 0.3 µg/kg/min, fentanyl 0.1 mg, propofol 154 mg, and rocuronium 46 mg were administered for induction of anesthesia. Tracheal intubation was performed orally. Anesthesia was maintained oxygen 1.0 L.min−1, air 2.0 L.min−1, propofol 5.0-7.0 mg.kg−1.h−1, and remifentanil 0.1-0.25 µg.kg−1.min−1. The surgery was completed as scheduled and the ICD was reactivated. The patient was then extubated after administration of sugammadex 200 mg. Conclusion: We report the successful management of anesthesia without lethal arrhythmia in a patient with ARVC and an ICD. An adequate amount of analgesia should be administered during general anesthesia to maintain adequate anesthetic depth and to avoid stress and pain.

Resumo Introdução e objetivo: A Cardiomiopatia Arritmogênica do Ventrículo Direito (CAVD) é uma cardiomiopatia genética caracterizada por taquicardia ventricular potencialmente letal. Descrevemos um paciente com CAVD com Cardioversor Desfibrilador Implantável (CDI) submetido a anestesia geral para cirurgia de seio maxilar. Relato do caso: Paciente masculino, 59 anos, a ser submetido a anestesia geral para cirurgia de seio maxilar. O paciente foi diagnosticado com CAVD há 15 anos, momento em que foi submetido a implante de CDI. A eletrocardiografia mostrou onda épsilon nas derivações II, aVR e V1-V3. O ecocardiograma transtorácico revelou função cardíaca normal. Após a entrada do paciente na sala de cirurgia, o CDI foi temporariamente desativado e uma via intravenosa foi instalada. Um desfibrilador externo foi mantido próximo ao paciente caso fosse detectada alguma anormalidade eletrocardiográfica que indicasse desfibrilação do paciente. Foram administrados 0,3 mg/kg/min de remifentanil, 0,1 mg de fentanil, 154 mg de propofol e 46 mg de rocurônio para indução da anestesia. A intubação traqueal foi realizada por via oral. A anestesia foi mantida com 1 L/min de oxigênio, 2 L/min de ar, 5-7 mg/kg/h de propofol e 0,1-0,25 µg/kg/min de remifentanil. O procedimento cirúrgico proposto foi concluído e o CDI foi reativado. O tubo traqueal foi retirado após administração de 200 mg de sugamadex. Conclusão: Descrevemos técnica de anestesia bem sucedida sem arritmia letal em paciente com CAVD e CDI. Analgesia adequada deve ser administrada durante a anestesia geral para manter profundidade anestésica correta e evitar estresse e dor.