Use of cilostazol in young patients with vagotonia related to bradycardia: description of 4 cases in adolescence

INTRODUCTION: Bradycardias in adolescents can be generated by diseases of the conduction tissue or by external influence (vagal tone, for example). Symptomatic Vagotonia may prompt healthcare professionals to early implant artificial cardiac stimulation devices. However, the transient aspects of vagotonia in the hebiatric population lead to the risk of over-indication. Phosphodiesterase inhibitors, such as cilostazol, can help with transient dysfunction by increasing the conduction of sodium channels in the depolarization phase (funny channels) of automatic cells. OBJECTIVES: To describe 4 cases of adolescents with bradycardia of extrinsic origin undergoing evaluation for permanent pacemaker implantation undergoing oral therapy with cilostazol. METHODS: Four adolescents (12, 15, 16, and 18 years old) were evaluated (3 patients were male and 1 female) with bradycardia of extrinsic origin - vagotonia (responsive to ergometry or atropine) and underwent drug therapy with cilostazol after ruling out the presence of ventricular arrhythmias caused by triggered activity. One patient had congenital heart disease (univentricular heart disease late PO of total cavopulmonary - single left ventricle without atrial isomerism). The others had structurally normal hearts. Ventricular function was preserved in all patients. All had sinus pauses longer than 2.5 s and paroxysmal atrioventricular block. The initial dose was 50mg/day, with dose progression up to 100 mg every 12 hours as the therapeutic goal. RESULTS: Only the patient with congenital heart disease was maintained on the initial dose due to a good Holter response and important improvement in oxygen saturation. There was a reduction of more than 90% in pauses with an average increase in HR without exacerbating periods of tachycardia on Holter monitoring (performed biweekly). After using cilostazol, heart rate variability in the time and frequency domains showed an improvement in the LF/HF ratio in all cases and a reduction in pNN50 in 75% of patients. There was no change in liver or kidney function while using the medication. All remained asymptomatic during follow-up from 3 months to 4 years. CONCLUSION: 1) The use of cilostazol reduces the parasympathetic/sympathetic imbalance with cilostazol in symptomatic pubescent adolescents may prevent pacemaker implantation in patients with transient vagotonia.

Probable atrioventricular reentry tachycardia (Node to Node) in a patient with right atrial isomerism in the immediate postoperative period of palliative surgery

INTRODUCTION: Patients with right atrial isomerism present duplicity of intracardiac structures, such as atrioventricular nodes. They thus present tachycardia of supraventricular reentry and responsive to adenosine therapy. In the postoperative period of palliative surgeries, the presence of tachycardia in these patients is not always related to junctional ectopic foci. OBJECTIVE: To describe a case of a patient with right atrial isomerism associated with complex heart disease with tachycardia maintained by AV reentry due to probable accessory AVN. Case report: 6-year-old girl with right atrial isomerism, total AV septal defect with vessels in transposition and anomalous intracardiac pulmonary vein drainage corrected at six months of age. She underwent central shunt replacement at 6 years of age. She has pulmonary hypertension, which requires palliative surgical support. After replacing the central shunt in the immediate postoperative period, she presented tachycardia with narrow QRS complexes and PR greater than RP with QRS onset at the beginning of the P wave of 120 ms and HR 188bpm. She had a BP of 65x40 mmHg and a capillary refill time of 5 seconds. Following ECG analysis and the 2020 PALS algorithm, adenosine was performed with immediate reversion to sinus rhythm and recovery of hemodynamic patterns. CONCLUSION: 1) Although tachycardias due to AV reentry are rarer in patients with right atrial isomerism due to Node to Node reentry, they should always be considered; 2) The use of adenosine in hemodynamically unstable supraventricular tachycardias should be the first choice when available; 3) electrocardiographic recording of the crisis allows for a more assertive diagnosis and more effective short- and long-term treatment.

Cardioinhibitory syncope 2b with 48-second pause in a patient with Down Syndrome and corrected AV septal defect: description of the case and therapeutic plan

INTRODUCTION: Syncope usually begins in adolescence. Approximately 20% of the population experiences their first episode of fainting between the ages of 10 and 20. Although extremely distressing, these are not always investigated. Only 25 to 50% of patients are evaluated in health services. However, some cases deserve treatment due to the risk of events and require specialized monitoring, including monitoring the indication of pacemaker devices (PM) in case of refractoriness to clinical treatment. This occurs in some cases of syncope with a neuromediated pattern of the cardioinhibitory type with pause (cardioinhibitory syncope 2b in the Tilt Test). OBJECTIVE: To describe the case of a post-pubertal patient with Down Syndrome and recent onset recurrent Syncope with a positive tilt test (TT) (2b response). CASE DESCRIPTION:13-year-old female patient with Down Syndrome with a total AV Septal defect in the post-operative phase of total correction with good surgical results. Recurrent syncope with prodromes (abdominal pain and pallor). She has Holter monitoring without arrhythmic changes and an echocardiogram with RVEF at the lower limit of normality. ECG analysis shows signs of the right anterior superior divisional block. She was submitted for evaluation by TT. She had performed a passive tilt protocol at 70 degrees without sensitization. After 5 minutes of rest, she was titled and remained stable for 7 minutes. In the eighth minute of tilting, she presented abdominal pain, followed by syncope with cardioinhibitory response 2b and a 48-second pause despite returning to the Trendelenburg position (-30 degrees). There was a return of the heartbeat with immediate recovery of the level of consciousness. Clinical treatment began with guidance on increasing water intake, suspending triggering factors (prolonged orthostasis, hot environments, for example) and maintaining strict monitoring to assess refractoriness and the need for PM indication. CONCLUSION: 1) Neuromediated syncope is particularly common during adolescence, especially after the growth spurt; 2) cardioinhibitory responses can appear suddenly and have significant repercussions. Despite this fact, clinical treatment must always be prioritized; 3) The patient must be monitored for recurrences and refractoriness to clinical therapy for the precise indication of PM in patients with cardioinhibitory syncope 2b with long pauses refractory to general measures.

Fascicular ventricular tachycardia in a schoolchild: the importance of diagnosis and exercise testing in the patient's therapeutic response - description of a case

INTRODUCTION: Ventricular arrhythmias are usually more severe than supraventricular arrhythmias and are less penetrant in acquiring knowledge among pediatric teams due to their greater rarity. This leads to diagnostic and therapeutic errors in specific cases, such as fascicular tachycardia (FT), with relatively narrow QRS complexes, which often harms the patient, directly interfering with their quality of life. FT manifests almost entirely as arrhythmias of a structurally normal heart triggered by effort and with well-defined electrocardiographic morphology with positivity in V1, axis deviated to the left, and, in some cases, the presence of dissociated P waves. OBJECTIVE: To describe the clinical aspects of a case of an 8-year-old schoolgirl with effort-induced tachycardia with FT pattern initially treated as supraventricular tachycardia. Case description: 8-year-old girl with tachycardia triggered by exertion with previous visits to the pediatric ER and diagnosed with supraventricular tachycardia. Initially, he received amiodarone for treatment. However, the tachycardia condition continued with minor self-limitation in an attempt to control the tachycardia episodes. An exercise test was requested, with easy onset of tachycardia with relatively narrow QRS complexes (110 ms) and positive morphology in V1 and axis deviation to the left. Analysis of long D2 shows the presence of AV dissociation and fusion, confirming the diagnosis of FT. It was decided to hospitalize the minor and reduce the dose of amiodarone, and introduce verapamil with progression up to 4.3 mg/kg/day with improvement in tachycardia episodes. A control exercise test was performed, and tachycardia was induced only with an HR greater than 170 bpm in sinus rhythm. The patient also reported significant symptom improvement within a short evaluation period (2 weeks). Radiofrequency ablation is being scheduled with a combined retro-aortic and transseptal approach. CONCLUSION: 1) The diagnosis of FT is based on knowledge of the typical electrocardiographic pattern; 2) Specific treatment with Verapamil (verapamil-sensitive arrhythmia)allows for an improvement in quality of life while awaiting definitive treatment with ablation; 3) The exercise test can serve as a therapeutic guide and guide the maximum HR to be reached by the patient before triggering FT crisis.

Uso do Cilostazol na adolescência para pacientes com bradicardia relacionada à vagotonia: descrição de uma série de casos / Cilostazol use in adolescence for patients with vagotonia-related bradycardia: case report

INTRODUÇÃO: As bradicardias em adolescentes podem ser geradas por doenças próprias no tecido de condução ou por influência externa(tônus vagal por exemplo). A vagotonia sintomática leva profissionais de saúde a precocemente indicar o implante de dispositivos de estimulação cardíaca artificial. Entretanto a exiguidade de próteses em nosso meio, relacionado à grande demanda e o caráter transitório da vagotonia na população hebiatrica leva ao receio da superindicação. Os inibidores de fosfodieterase como o cilostazol podem auxiliar na disfunção transitória por aumentar a condução dos canais de sódio na fase de despolarização espontânea (canais funny) das células automáticas. OBJETIVO: Descrever 4 casos de adolescentes com bradicardia de causa extrínseca em avaliação para implante de marca-passo definitivo submetidos à terapia oral com cilostazol. RESULTADOS: Foram avaliados 4 adolescentes (12,15,16 e 18 anos), sendo 3 masculinos, com bradicardia de origem externa (responsivas à ergometria ou atropina) foram submetidos à terapia medicamentosa com cilostazol após descartarse arritmias ventriculares originadas por atividade deflagrada. Uma paciente possuia cardiopatia congênita (cavopulmonar total - ventrículo único tipo esquerdo sem isomerismo atrial). Os demais possuíam coração estruturalmente normal. A função ventricular estava preservada em todos. Todos apresentavam pausas sinusais superiores a 2,5s e ou bloqueios atrioventriculares paroxísticos. A dose inicial de 50 mg/dia foi introduzida com progressão da dose até 100 mg a cada 12 horas como objetivo terapêutico. Apenas a portadora de cardiopatia congênita foi mantida com a dose inicial devido boa resposta do Holter e na saturação. Em todos houve redução de mais de 90% das pausas com elevação da FC média sem exacerbação dos períodos de taquicardia ao Holter (periodicidade quinzenal). A variabilidade da frequência cardíaca no domínio do tempo e da frequência após o uso do fármaco apresentou melhora da relação LF/HF em todos os casos e redução do pNN50 em 75% dos pacientes. Não houve alteração hepática ou renal durante o uso de medicação. Todos estiveram assintomáticos durante o seguimento de 3 meses a 4 anos. CONCLUSÃO: 1) O uso de cilostazol diminui o desbalanço simpático parassimpático reduzindo episódios de pausas e bradicardias; 2) O tratamento do desequilíbrio autonômico com cilostazol em adolescentes púberes sintomáticos pode evitar o implante de dispositivo anti bradicardia. (AU)