RÉSUMÉ
RESUMEN Introducción: El accidente cerebrovascular (ACV) puede generar perturbaciones funcionales y eléctricas del corazón. Las características y mecanismos subyacentes no están completamente elucidados. Objetivo: Evaluar si la isquemia (I) y reperfusión (R) cerebral agudas ocasionan disfunción cardíaca y alteraciones electrocardiográficas en un modelo experimental en ratones. Material y Métodos: Ratones macho sometidos a isquemia y reperfusión cerebral (I/R) fueron evaluados mediante electrocardiografía (ECG) y ecocardiografía. Se analizó la frecuencia cardíaca, el intervalo QT corregido (QTc) y el intervalo entre el pico de la onda T - fin de la onda T (Tp-Te), la fracción de eyección ventricular izquierda (FEVI), la fracción de acortamiento (FA) y el tiempo de relajación isovolumétrica (TRIV). Se cuantificó el tamaño del infarto cerebral (TI), y el déficit neurológico se evaluó con la escala de Longa (EL). Resultados: Encontramos una disminución estadísticamente significativa de la FEVI a las 24 horas de R (I/R: 66,5 ± 1,5% vs. sham: 74,3 ± 0,9%; p=0,002) y la FA (I/R: 42,9 ± 1,7% vs. sham: 52,3 ± 1,7%; p=0,004). Se observó una prolongación del QTc durante la I/R (basal: 125,1 ± 4,3 ms; 60 min I: 143,8 ± 5,2 ms; 24 horas R: 170,3 ± 5,8 ms; p=0,002), sin una prolongación del Tp-Te en la I (basal: 25,9 ± 1,3 ms vs. 60 min I: 23,8 ± 1,4 ms; p=0,999) pero sí en la R (24 horas R: 32,0 ± 2,3 ms; p=0,049. El tamaño del infarto cerebral fue de 34,9 ± 2,5% y la supervivencia del grupo I/R fue del 43,3%. Conclusión: La isquemia cerebral aguda induce una disfunción ventricular izquierda leve y trastornos en la repolarización ventricular que se intensifican en las primeras 24 horas de reperfusión.
ABSTRACT Background: Stroke may produce functional and electrical heart disturbances. The underlying characteristics and mechanisms have not been fully elucidated. Objectives: To evaluate whether acute cerebral ischemia (I) and reperfusion (R) may cause cardiac dysfunction and electrocardiographic alterations in an experimental mice model. Methods: Male mice that underwent cerebral ischemia and reperfusion (I/R) were evaluated by electrocardiography (ECG) and echocardiography. Heart rate, corrected QT (QTc) interval, T-wave peak to T-wave end (Tp-Te) interval, left ventricular ejection fraction (LVEF), shortening fraction (SF) and isovolumetric relaxation time (IVRT) were analyzed. Cerebral infarct size was calculated, and neurological deficit was assessed with the Longa scale. Results: Twenty-four hours after R, a statistically significant decrease in LVEF (I/R: 66.5±1.5% vs. sham: 74.3±0.9%; p=0.002) and in SF (I/R: 42.9±1.7% vs sham: 52.3±1.7%; p=0.004) was observed. QTc interval prolongation was observed during I/R (baseline: 125.1±4.3 ms; 60 min after I: 143.8±5.2 ms; 24 h after R: 170.3±5.8 ms; p=0.002). Tp-Te interval was not prolonged during I (baseline: 25.9±1.3 ms vs. 60 min after I: 23.8±1.4 ms; p=0.999) but it was prolonged during R (24 h after R: 32.0±2.3 ms; p=0.049). Cerebral infarct size was 34.9±2.5% and survival in the I/R group was 43.3%. Conclusion: Acute cerebral ischemia induces mild left ventricular dysfunction and disturbances in ventricular repolarization which intensify within the first 24 hours after reperfusion.
RÉSUMÉ
Background: Bedaquiline (BDQ) is indeed recommended for treating multidrug-resistant tuberculosis (MDR-TB). However, it's essential to monitor patients receiving bedaquiline therapy closely because it has been associated with prolongation of the QTc interval. This study aimed to assess the association of bedaquiline to QT interval prolongation in DR-TB patients. Methods: This was an observational longitudinal study conducted in the Department of Respiratory Medicine in Chest Disease Hospital, Rajshahi, from August 2020 to February 2023. A total of 44 MDR-TB patients were included in the study. Data analyses were done by using Statistical Package for Social Sciences (SPSS) version 25.0. Results: Out of 44 patients the majority 30(68.2%) patients belonged to age >40 years with a mean age of 49.3±15.6 years, and all patients were male. All MDR patients were detected by sputum Gene-Xpert, 44 (100%), and sputum for AFB culture was done in all patients, 44 (100%). QT level and QT changes were statistically significant for baseline and 24 weeks. Only one patient died in 2 weeks of follow-up (Table 3). Changes of QT >60 ms was found in 6 (13.6%) and ?60 ms was 38 (86.4%). Age, sex, marital status, residence, educational status, occupational status, monthly income, chief complaints, co-morbidities, and using drug-causing QT prolongation were not statistically significant (p>0.05). Conclusions: Prolonged QT interval is in DR-TB patients who receive treatment using the bedaquiline regimen. We observed that with a moderate prolongation of QTc, there were no arrhythmias recorded and 1 death occurred due to acute MI.
RÉSUMÉ
Resumo Fundamento: O software ablation index (AI) permitiu melhorar os resultados da ablação de fibrilação atrial (FA), mas as taxas de recorrência permanecem significativas. Biomarcadores séricos específicos têm sido associados a essa recorrência. Objetivos: Avaliar se certos biomarcadores podem ser utilizados (individualmente ou combinados) para predizer a recorrência de FA pós ablação guiada pelo AI. Métodos: Estudo multicêntrico, observacional, prospectivo de pacientes consecutivos, encaminhados para ablação de FA de janeiro de 2018 a março de 2021. Hemoglobina, peptídeo natriurético cerebral (BNP), proteína C reativa, troponina I ultrassensível, clearance de creatinina, Hormônio Tireoestimulante (TSH), e Tiroxina livre (T4) foram avaliados quanto à capacidade de prever a recorrência de arritmias durante o acompanhamento. Valores de p <0,05 foram aceitos como estatisticamente significativos. Resultados: Um total de 593 pacientes foram incluídos - 412 com FA paroxística e 181 com FA persistente. Durante o seguimento médio de 24±6 meses, 76,4% não apresentaram recidiva após ablação. Individualmente, os biomarcadores demonstraram um valor preditivo baixo ou nulo para recorrência. No entanto, TSH >1,8 μUI/mL [HR=1,82 (IC95%, 1,89-2,80), p=0,006] foi um preditor independente de recorrência. Avaliando-se a combinação de TSH, FT4 e BNP, a adição de cada valor "anormal" foi associada a uma menor sobrevida livre de recorrência (87,1% se nenhum vs. 83,5% se um vs. 75,1% se dois vs. 43,3% se três biomarcadores, p<0,001). Doentes com três biomarcadores "anormais" apresentaram três vezes maior probabilidade de recorrência de FA, comparativamente aos que não apresentaram nenhum biomarcador "anormal" (HR=2,88 [IC95%, 1,39-5,17], p=0,003). Conclusões: Quando combinados, valores anormais de TSH, FT4 e BNP podem ser uma ferramenta útil para prever a recorrência de FA pós ablação guiada pelo AI.
Abstract Background: Ablation Index (AI) software has allowed better atrial fibrillation (AF) ablation results, but recurrence rates remain significant. Specific serum biomarkers have been associated with this recurrence. Objectives: To evaluate whether certain biomarkers could be used (either individually or combined) to predict arrhythmia recurrence after AI-guided AF ablation. Methods: Prospective multicenter observational study of consecutive patients referred for AF ablation from January 2018 to March 2021. Hemoglobin, brain natriuretic peptide (BNP), C-reactive protein, high sensitivity cardiac troponin I, creatinine clearance, thyroid-stimulating hormone (TSH) and free thyroxine (FT4) were assessed for their ability to predict arrhythmia recurrence during follow-up. Statistical significance was accepted for p values of<0.05. Results: A total of 593 patients were included - 412 patients with paroxysmal AF and 181 with persistent AF. After a mean follow-up of 24±6 months, overall single-procedure freedom from atrial arrhythmia was 76.4%. Individually, all biomarkers had no or only modest predictive power for recurrence. However, a TSH value >1.8 μUI/mL (HR=1.82 [95% CI, 1.89-2.80], p=0.006) was an independent predictor of arrhythmia recurrence. When assessing TSH, FT4 and BNP values in combination, each additional "abnormal" biomarker value was associated with a lower freedom from arrhythmia recurrence (87.1 % for no biomarker vs. 83.5% for one vs. 75.1% for two vs. 43.3% for three biomarkers, p<0.001). Patients with three "abnormal" biomarkers had a threefold higher risk of AF recurrence compared with no "abnormal" biomarker (HR=2.88 [95% CI, 1.39-5.17], p=0.003). Conclusions: When used in combination, abnormal TSH, FT4 and BNP values can be a useful tool for predicting arrhythmia recurrence after AI-guided AF ablation.
RÉSUMÉ
Arrhythmia is an important disease among cardiovascular diseases. Malignant arrhythmias often occur clinically and are induced by abnormal ion channels, electrical activity disorders, myocardial fibrosis, inflammation, dysfunctional mitochondrial biogenesis, mitochondrial calcium overload, out-of-balance energy metabolism, oxidative stress, sympathetic hyperactivity, and other pathological cardiac remodeling, and they are the main causes of sudden cardiac death. In traditional Chinese medicine, arrhythmias are considered to be palpitations, which are commonly caused by deficiency of Qi and Yin. It is often manifested as a deficiency of the spleen and stomach, resulting in malfunction of the Qi mechanism, followed by a particularly severe decline in cardiac function. Shengmaisan is a representative formula for nourishing Qi and Yin, consisting of Ginseng Radix et Rhizoma, Ophiopogonis Radix, and Schisandrae Chinensis Fructus. In recent years, clinical studies have shown that Shengmaisan and its additions and subtractions are commonly used in the treatment of arrhythmias. In this article, the mechanisms of the active ingredients of Shengmaisan in the electrophysiology, biochemistry, structure, autonomic nervous system, and subcellular fraction of the heart are reviewed, and the multi-target, multi-system, and integrality of Shengmaisan in the treatment of arrhythmias of Qi and Yin deficiency are described. In addition, energy metabolism disorder is tightly juxtaposed with Qi and Yin deficiency syndrome. Mitochondria, as the center of myocardial energy metabolism, play a paramount role in cardiac remodeling, indicating that Shengmaisan will be a salient part of future research to ameliorate cardiac pathologic remodeling through energy metabolism of mitochondria, so as to provide a theoretical basis for the clinical treatment of these arrhythmias.
RÉSUMÉ
Objective To investigate the efficacy of dronedarone combined with low dose metoprol-ol in the treatment of atrial tachycardia.Methods A total of 175 elderly patients with atrial tachy-cardia admitted in Northern Jiangsu People's Hospital during January 2020 to January 2022 were enrolled and then randomly divided into dronedarone group(n=57),metoprolol group(n=55)and combined group(dronedarone+metoprolol,n=48).The frequency,duration and symptom changes of arrhythmia were compared before and after treatment.Results After 3 and 6 months of administration,the total effective rate was significantly higher in the combination group than the dronedarone group and the metoprolol group(P<0.05).The frequency of atrial fibrillation(AF)attacks[(2.31±1.78)/48 h vs(11.56±18.68)/48 h],AF duration[(4.86±6.73)h/48 h vs(10.92±9.61)h/48 h],atrial flutter(AFL)attacks[(2.33±1.53)/48 h vs(4.33±1.53)/48 h]and AFL duration[(5.15±4.87)h/48 h vs(21.54±20.08)h/48 h]in the combined group,and AFL duration[(2.75±1.94)h/48 h vs(10.29±8.04)h/48 h]in the dronedarone group were reduced after 6 months of treatment(P<0.05).Conclusion In the treatment of atrial tachycardia,dronedarone combined with low dose metoprolol can not only obviously improve symptoms,but also significantly reduce the atrial premature and atrial tachycardia attacks,decrease the number and duration of AF and AFL attacks,and control heart rate effectively.
RÉSUMÉ
Objective:To investigate the efficacy of trimetazidine in the treatment of atrial arrhythmias in patients with ischemic cardiomyopathy and heart failure and analyze the effect of trimetazidine on cardiac function and atrial arrhythmias.Methods:A total of 79 patients with ischemic cardiomyopathy and heart failure who received treatment at the Second Hospital of Jiaxing from December 2018 to June 2020 were included in this study. These patients were randomly divided into an observation group ( n = 41) and a control group ( n = 38). Patients in the control group received conventional drugs, while those in the observation group received trimetazidine sustained-release tablets twice daily, each time taking 35 mg in addition to conventional drugs. The treatment lasted for 24 weeks. Before and after treatment, cardiac function indicators (left ventricular ejection fraction, B-type brain natriuretic peptide, 6-minute walking distance), cardiac color Doppler ultrasound indicators [ratio of early to late peak filling rate (E/A ratio)], left ventricular fractional shortening), electrocardiogram parameters (maximum P-wave duration, minimum P-wave duration, and P-wave dispersion), dynamic electrocardiogram parameters [number of single atrial premature beats, total number and duration of paroxysmal atrial tachycardia episodes, total number and duration of paroxysmal atrial flutter/fibrillation attacks, standard deviation of RR intervals, root mean square of successive differences between normal heartbeats, proportion of successive RR intervals that differ by more than 50 ms divided by the total number of NN intervals (PNN50), standard deviation of average NN intervals, high frequency and low frequency], as well as changes in high sensitivity C-reactive protein were analyzed in each group. Results:After treatment, left ventricular ejection fraction, B-type brain natriuretic peptide, 6-minute walking distance, maximum P-wave duration, P-wave dispersion, total number of atrial flutter/atrial fibrillation attacks, and duration of atrial flutter/atrial fibrillation in the observation group were (51.05 ± 7.68)%, (1 615.59 ± 1 129.78) ng/L, (350.02 ± 62.99) m, (99.73 ± 11.60) ms, (22.44 ± 12.03) ms, (0.22 ± 0.61), and (4.59 ± 12.30) minutes, respectively, which were significantly superior to (46.82 ± 7.34)%, (2 267.47 ± 1 539.03) ng/L, (294.16 ± 58.20) m, (111.71 ± 10.00) ms, (36.77 ± 15.07) ms, (0.76 ± 1.13), (15.66 ± 22.30) minutes in the control group, t = -2.95, 2.16, -4.08, 4.89, 4.68, 2.69, 2.76, all P < 0.01). Conclusion:Trimetazidine can effectively reduce atrial arrhythmias and improve the prognosis of patients with ischemic cardiomyopathy and heart failure, which warrants clinical promotion.
RÉSUMÉ
Dopamine is the precursor of biosynthesis of norepinephrine. Low-dose dopamine mainly excites dopamine receptors, which may dilate renal and mesenteric vessels, increase renal blood flow and improve the microcirculation. In recent years, low-dose dopamine has been widely applied in the field of kidney transplantation due to its vasoactive effect. However, with the development of evidence-based medicine, the role of dopamine in protecting the perfusion function of renal allograft in kidney transplantation has been questioned. Multiple studies have shown that dopamine brings no significant benefit to renal and cardiac function in kidney transplantation, exerts low pressor effect, and may even increase the risk of perioperative complications. Norepinephrine may be used as a safe substitute. In this article, recent progress in the effect of dopamine upon renal and cardiac function and hemodynamics during kidney transplantation was reviewed, aiming to provide reference for clinical application of dopamine in kidney transplantation.
RÉSUMÉ
Abstract Background A recently identified viral illness called coronavirus disease 2019 (COVID-19) is spreading quickly. Numerous cardiovascular issues such as arrhythmias and electrocardiogram (ECG) alterations have been linked to COVID-19. Objective In this investigation, we compared ECG indicators of depolarization and repolarization heterogeneity between symptomatic individuals who complained of palpitations and chest discomfort following COVID-19 and those who did not. Methods In this prospective case-control study, 56 post-COVID-19 patients who did not have any symptoms of chest discomfort or palpitations were included in the control group and compared with a study group comprising 73 post-COVID-19 patients who presented at the outpatient clinic with complaints of chest pain and palpitation. Electrocardiographic (ECG) measures were used to assess depolarization and repolarization of the ventricles. These measures included the Tpeak-Tend (Tp-e) interval, QT dispersion (QTd), Tp-e/QT ratio, Tp-e/QTc ratio, frontal QRS-T (fQRS-T) angle, and fragmented QRS (FQRS). Two cardiologists recorded the patients' ECG data. A statistically significant result was defined as a p value less than 0.05. Results The results of multivariate analysis including FQRS, Tp-e interval, Tp-e/QT, and Tp-e/cQT showed that presence of FQRS (OR: 6.707, 95% CI: 1.733-25.952; p = 0.006) was an independent predictor of symptomatic post-COVID -19 patients. Conclusion In our study, FQRS was found to be significantly higher in symptomatic post-COVID-19 patients than in non-symptomatic post-COVID-19 patients, while Tp-e interval was found to be lower.
RÉSUMÉ
El embarazo se asocia con un mayor riesgo de arritmias y las pacientes con antecedentes de arritmias tienen un riesgo significativo de recurrencia durante el embarazo. Esta revisión analiza el diagnóstico y tratamiento de las arritmias más frecuentes durante el embarazo y algunas situaciones especiales. Debido a los potenciales riesgos para la madre y para la salud fetal, se necesita un enfoque multidisciplinario e integrador para el manejo de las arritmias desde el período preparto hasta el posparto.
Pregnancy is associated with an increased risk of arrhythmias, and patients with a history of arrhythmias have a significant risk of recurrence during pregnancy. This review analyzes the diagnosis and treatment of the most common arrhythmias during pregnancy and some special situations. Due to the potential risks to maternal and fetal health, a multidisciplinary and integrative approach is needed for the management of arrhythmias from the prepartum to the postpartum period.
A gravidez está associada a um risco acrescido de arritmias, as mulheres com um historial de arritmias apresentam um risco significativo de recorrência na gravidez. Esta revisão analisa o diagnóstico e o tratamento das arritmias mais comuns na gravidez e ainda algumas situações especiais. Devido aos riscos potenciais para a mãe e para a saúde do feto é necessária uma abordagem multidisciplinar e integrada para o tratamento das arritmias desde o período anteparto até ao pós-parto.
RÉSUMÉ
Introducción: Las evidencias científicas han demostrado que durante el período pandémico por la COVID-19 ha existido un incremento de la incidencia de muerte súbita cardiovascular, proporcional al incremento de los casos y a la letalidad por la enfermedad. Objetivos: Compilar información sobre los fármacos empleados en el tratamiento de la COVID-19 y sus posibles efectos en la prolongación del intervalo QT y la aparición de muerte súbita. Métodos: Se realizó una búsqueda de información a partir de las bases de datos PubMed, Medline y SciELO, en los idiomas español e inglés en el período de enero de 2020 a enero de 2023. Resultados: Los hallazgos más recientes sugieren que los factores relacionados con el tratamiento médico del paciente para sus enfermedades cardiovasculares previas, el empleo concomitante de drogas para otras comorbilidades, el ensayo de nuevas drogas que se investigan en la actualidad para el tratamiento de la enfermedad y el uso inadecuado de fármacos en complicaciones graves por la COVID-19, pueden ocasionar prolongación del intervalo QT y arritmias ventriculares tipo torsades de pointes, lo que puede conllevar a la aparición de muerte súbita. Conclusiones: Ha sido demostrado el efecto deletéreo de los fármacos en el tratamiento de la COVID-19 y sus posibles asociaciones a la terapéutica del paciente, en la prolongación del tiempo de repolarización ventricular cardíaca, cuya traducción eléctrica es un intervalo QT prolongado y su contribución a la génesis de arritmias malignas potencialmente fatales capaces de desencadenar un paro cardíaco y evolucionar a la muerte súbita(AU)
Scientific evidence has shown an increase in the incidence of sudden cardiovascular death during the COVID-19 pandemic period. This has been proportional to the increase in cases and mortality from the disease. Direct and indirect injury to the myocardium and vascular system allow to partially explain the statistics. Among the factors related to the medical treatment of the patient for previous cardiovascular diseases, it is the concomitant use of drugs for other comorbidities. The trial of new drugs for the treatment of this condition and the inappropriate use of drugs in serious complications from COVID-19 are currently being investigated. These can cause QT prolongation and torsades de pointes ventricular arrhythmias, which can lead to sudden death. Monitoring the QT interval is recommended, before and during treatment, in patients who come to the emergency room with a clinical condition suggestive of COVID-19. Additionally, modifiable factors favoring its prolongation should be evaluated. Decision-making in the application of therapeutic protocols in patients with COVID-19 with prolonged QTc at baseline, or with increased QTc after starting treatment, must go through the analysis of the risk/benefit ratio defined by a multi- and interdisciplinary team(AU)
Sujet(s)
Humains , Mâle , Femelle , Troubles du rythme cardiaque , Syndrome du QT long , Mort subite cardiaque/épidémiologie , Effets secondaires indésirables des médicaments , COVID-19/épidémiologieRÉSUMÉ
Objetivo: relatar a elaboração de um algoritmo para facilitar a interpretação rápida das principais arritmias cardíacas no eletrocardiograma. Método: estudo descritivo, exploratório, com abordagem qualitativa, do tipo relato de experiência, realizado mediante um projeto de intervenção em educação em saúde durante o ano de 2021. Resultados: a elaboração do algoritmo denominado Scaritmo contribuiu para sistematizar as etapas de identificação de arritmias cardíacas, favorecendo o processo didático e aprendizado dos estudantes e otimizando a interpretação rápida do eletrocardiograma. Conclusão: o uso do algoritmo Scaritmo permite a sistematização teórico-prática das etapas necessárias para a interpretação do eletrocardiograma tornando sua avaliação mais didática e assertiva pelo examinador em treinamento.(AU)
Objective: to report the development of an algorithm to facilitate the rapid interpretation of the main cardiac arrhythmias in electrocardiogram. Method: a descriptive, exploratory study with qualitative approach, of experience report type, conducted through an intervention project in health education during the year 2021. Results: The development of the algorithm called Scaritmo contributed to systematize the steps of cardiac arrhythmia identification, favoring the didactic process and student learning, and optimizing the rapid interpretation of the electrocardiogram. Conclusion: The use of the Scaritm algorithm allows the theoretical and practical systematization of the steps necessary for the interpretation of electrocardiograms, making its evaluation more didactic and assertive by the examiner in training.(AU)
Objetivo: relatar el desarrollo de un algoritmo para facilitar la interpretación rápida de las principales arritmias cardíacas en electrocardiograma. Método: estudio descriptivo, exploratorio, con abordaje cualitativo, de tipo relato de experiencia, realizado a través de un proyecto de intervención en educación para la salud durante el año 2021. Resultados: el desarrollo del algoritmo denominado Scaritmo contribuyó para sistematizar los pasos de identificación de arritmias cardíacas, favoreciendo el proceso didáctico y el aprendizaje de los alumnos y optimizando la rápida interpretación del electrocardiograma. Conclusión: El uso del algoritmo Scaritmo permite la sistematización teórica y práctica de los pasos necesarios para la interpretación del electrocardiograma, tornando su evaluación más didáctica y asertiva por el examinador en formación.(AU)
Sujet(s)
Troubles du rythme cardiaque , Éducation pour la santé , ÉlectrocardiographieRÉSUMÉ
Abstract Background: Coronavirus disease 2019 (COVID-19) mainly affects the respiratory system, while the most common extrapulmonary complication of COVID-19 is cardiovascular involvement. Objective: To identify the frequency of electrocardiographic changes and cardiac arrhythmias in patients hospitalized with COVID-19 infection. Methods: This was a cross-sectional study, including patients aged >18 years with diagnosis of severe acute respiratory syndrome coronavirus 2 infection in a high-complexity hospital in Santiago de Cali, Colombia, from March to September 2020. A descriptive analysis with an analytical component and multiple logistic regression analysis were performed; all estimates were established with a 95% confidence level (CI) and a 5% significance level. Results: This study included 183 individuals; of whom 160 were considered for electrocardiographic analysis, 63% of which evidenced significant findings, the most frequent being sinus tachycardia (29.4%). The frequency of myocardial injury was 21.9% and was more common among non-survivors than among survivors (41.7% vs. 12.2%, p < 0.001). Myocardial injury was also significantly more common in patients who presented electrocardiographic findings than those who did not (26.5% vs. 12.1%, p = 0.032) and in those who required intensive care admission (31.8% vs 10.5%, p < 0.001). The strongest mortality-associated factor was the need for mechanical ventilation — odds ratio (OR), 9.14; 95% confidence interval, 3.4-24.5. Conclusions: Electrocardiographic findings in patients with COVID 19 are frequent, including newly diagnosed arrhythmias, justifying the use of cost-effective tools for the initial approach and follow-up of this affected population. Worse outcomes depend on factors such as invasive mechanical ventilation, comorbidities, age, and superinfection.
RÉSUMÉ
Background & Objective: Despite the burden of sudden cardiac arrest (SCA) worldwide, implantable cardioverter-defibrillators (ICDs) are underutilized, particularly in Asia, Latin America, Eastern Europe, the Middle East, and Africa. The Improve SCA trial demonstrated that primary prevention (PP) patients in these regions benefit from an ICD or a cardiac resynchronization therapy defibrillator (CRT-D). We aimed to compare the rate of device therapy and mortality among ischemic and non-ischemic cardiomyopathy (ICM and NICM) PP patients who met guideline indications for ICD therapy and had an ICD/CRT-D implanted. Methods: Improve SCA was a prospective, non-randomized, non-blinded multicenter trial that enrolled patients from the above-mentioned regions. All-cause mortality and device therapy were examined by cardiomyopathy (ICM vs NICM) and implantation status. Cox proportional hazards methods were used, adjusting for factors affecting mortality risk. Results: Of 1848 PP NICM patients, 1007 (54.5%) received ICD/CRT-D, while 303 of 581 (52.1%) PP ICM patients received an ICD/CRT-D. The all-cause mortality rate at 3 years for NICM patients with and without an ICD/CRT-D was 13.1% and 18.3%, respectively (HR 0.51, 95% CI 0.38e0.68, p < 0.001). Similarly, all-cause mortality at 3 years in ICM patients was 13.8% in those with a device and 19.9% in those without an ICD/CRT-D (HR 0.54, 95% CI 0.33e.0.88, p ¼ 0.011). The time to first device therapy, time to first shock, and time to first antitachycardia pacing (ATP) therapy were not significantly different between groups (p 0.263). Conclusions: In this large data set of patients with a guideline-based PP ICD indication, defibrillator device implantation conferred a significant mortality benefit in both NICM and ICM patients. The rate of appropriate device therapy was also similar in both groups.