Diagnosis of catecholaminergic polymorphic ventricular tachycardia during late adulthood due to a rare genetic variant in RYR2: a case report

Background Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a severe hereditary channelopathy characterized by the presence of ventricular arrhythmias triggered by adrenergic stimuli, usually diagnosed in the first two decades of life. Genetic variants in the cardiac ryanodine receptor gene are the most frequently occurring that cause an increase in intracellular calcium concentration and thus induce ventricular arrhythmias due to a delayed after depolarisation-induced triggered activity. Case presentation We present the case of a 74-year-old male, a regular athlete with no relevant family history who suffered from sinus dysfunction and frequent premature ventricular complexes with no symptoms. A treadmill test revealed severe polymorphic ventricular arrhythmias which led to the suspicion of CPVT. A genetic study was undertaken, and it identified a rare genetic variant in the RYR2 gene which was possibly associated with its development in heterozygosity: c.14465G > A, p.Arg4822His. While evaluating the co-segregation, we observed that most of his relatives exhibit polymorphic ventricular arrhythmias with exertion without symptoms and carried the same variant. Conclusions We described, for the first time, the clinical characteristics and co-segregation of a family diagnosed with CPVT secondary to a little-known genetic variant of the RYR2 gene. It is a variant that, in our case study, suggests an association with a very good prognosis.

Incidence and type of arrhythmias recorded by one-month continuous ECG monitoring in stroke patients

Funding Acknowledgements Type of funding sources: None. BACKGROUND The incidence of atrial fibrillation (AF) following stroke has been studied with implantable loop recorders. However, these devices do not record short lasting AF episodes (<30-120 seconds [s]). In addition, the incidence and type of other clinically relevant arrhythmias is poorly understood in this clinical setting. PURPOSE To evaluate the incidence, type and clinical relevance of arrhythmias detected by one-month continuous ECG monitoring in patients after cryptogenic stroke. MATERIAL AND METHODS Consecutive patients (p) with stroke and no previous AF or other cardioembolic or atheroembolic causes were prospectively enrolled in the study. An external wearable 2-lead ECG monitoring system (NUUBO) was used for 30 days (d) in all of them after the acute phase of the stroke. In the absence of documented AF, a parafibrillatory status was defined as >3000 atrial ectopic beats/d or >2 "micro AF" episodes (fibrillatory burst <30 s)/d or ≥1 episode of "micro AF" >14 s. RESULTS 130 p. were included in the study (age 73 ± 12, 57% males, 19% previous stroke, 7% ischemic cardiopathy, CHA2DSVA2Sc pre-stroke 3.1 ± 1.7). 3 were withdrawn from the study due to inadequate use (recording time <14 d) and 1 due to stroke during SARS-CoV2 infection. Total recording time was 28 ± 3 d, total analyzable ECG time was 23 ± 5 d. ECG monitoring was repeated in 12 (9.5%) p due to poor ECG quality in 6 p or high suspicion of AF despite an initial negative result in 6 p. AF >30 s was detected in a total of 27 (21.4%) p, average AF duration was 52 hours (range 30 s-22 d). AF >30s was detected in 2 (17%) p with repeated monitoring. All these patients were placed on anticoagulation. Sustained paroxysmal supraventricular tachycardia (SVT) was documented in 4 (4.4%) p without AF. All episodes of AF and SVT were asymptomatic. Mobitz I second degree AV block in 4 (3.2%) p. 3 (2.4%) p had a pacemaker implanted: 2 for severe sinus dysfunction and 1 for AV block. High-density ventricular ectopy (>3000/d) was present in 7 (6%) p and ≥1 episode of non-sustained ventricular tachycardia was detected in 26 (21%) p. A parafibrillatory status was identified in 27 (21%) p with no AF >30 s. At 1-year follow up 4/22 (18%) of patients with parafibrillatory status and 3/59 (5%) without parafibrillatory status suffered a new stroke (p = 0.08). CONCLUSIONS AF and other potentially relevant arrhythmias are frequent after stroke and easily detectable with one-month non-invasive continuous ECG monitoring. Patients with a parafibrillatory status could benefit from longer monitoring time to detect AF.

Pacemakers capable of monitoring sleep-disordered breathing: impact on sleep apnea detection in real life

Background Pacemaker recipients are at high-risk of sleep apnea (SA). New generation of pacemakers allow day by day, sleep-disordered breathing (SDB) monitoring. These devices measure variations in thoracic impedance and can detect apnea and hypopnea. Purpose The aim was To compare the rate of SA detection in patients implanted with and without pacemaker capable of monitoring (SDB). Methods This retrospective study included all consecutive patients implanted with a pacemaker between 2013 and 2016 at Poitiers university hospital. Pacemaker recipients allowing SDB monitoring (SDB monitoring group) and pacemaker recipients not allowing SDB monitoring (control group) were compared in terms of SA diagnosis, continuous positive airway pressure (CPAP) therapy initiation, newly AF discovered and stroke occurrence. Results Among the 1442 patients included (mean age 79 years, 39% of women, BMI = 27 kg/m2). 653 were in the SDB monitoring group and 789 in the control group. The 2 groups were not different in terms of age, body mass index, cardiovascular risk factor, cardiac function, and medication. Indication for cardiac pacing was atrioventricular block and sinus dysfunction in 56% and 23% of patients respectively. Mean follow-up was 24.7 months. 40 patients (7.5%) have been diagnosed with SA in the SDB monitoring group and 18 (2.7%) in the control group (p<0.001). CPAP therapy was initiated in 33 (5%) patients in SDB monitoring group and in 16 (2%) patients for the control group (p=0.01). The rate of newly diagnosed AF was 15% in SDB monitoring and 7% in control group (p<0.001). The incidence of stroke was 16 (2.4%) in the SDB monitoring group and 18 (3.4%) in the control group (P=0.45). Conclusion In real life conditions, pacemakers capable of monitoring SDB improve the diagnosis of SA and CPAP therapy rate. Monitoring of sleep apnea after at least Funding Acknowledgement Type of funding source: None

Pacemaker Therapy

The number of permanent pacemakers implanted per year increased by 55.6% between 1993 and 2009, and is continuing to rise. Accordingly, the number of patients treated in the emergency department who have permanent pacemakers is increasing, and it is important for physicians in the emergency department to be familiar with the operation and potential complications of these devices. This review covers the pathophysiology, stabilization and assessment, diagnosis and treatment, and disposition and outcomes for patients with pacemakers presenting to the emergency department. This review contains 6 figures, 10 tables, and 25 references. Keywords: Pacemaker, sinus node, atrioventricular block, supraventricular tachycardia, bifascicular block, carotid sinus dysfunction, cardiac sarcoidosis, ventricular pacing, cardiac resynchronization therapy

Gastric Dysrhythmia Corrected by Dual Chamber Pacemaker Implantation

HighlightsNausea has been defined as an “unpleasant painless subjective feeling that one will imminently vomit”. While nausea and vomiting are often thought to exist on a temporal continuum, this is not always the case. There are situations when severe nausea may be present without emesis and less frequently, when emesis may be present without preceding nausea. The underlying mechanisms involved in nausea are complex and encompass psychological states, the central nervous system, autonomic nervous system, gastric dysrhythmias, and the endocrine system. We report a 92-year-old male patient with depression, hypothyroidism, and intermittent severe sinus dysfunction, causing nausea, vomiting, and fatigue, pre-syncope and low cerebral output. Dual chamber implantation was performed and 24 hours after the implantation of the device all the symptoms disappeared, the parameters of the pacemaker were stable, and the patient was discharged. At the 1st and the 3rd month after implantation the patient remained asymptomatic. Over-activity of autonomic outflow may be a determinant for overall nausea intensity, probably, may be a potential therapeutic target to be corrected, at least in part, by a dual chamber pacemaker implantation.

Seizure Triggered by Sick Sinus Syndrome

Sick sinus syndrome (SSS) is a dysfunction of sinoatrial node resulting in symptomatic bradycardia or sinus pauses causing decreased cardiac output with cerebral hypoperfusion and usually presents as syncope, presyncope or fatigue. The occurrence of a seizure is very rare. A 69-year-old man suffered two episodes of generalised tonic–clonic seizures. MRI and electroencephalogram failed to reveal the cause of seizures. In the emergency room, he experienced presyncope simultaneous to bradycardia and sinus pauses. He was stabilised with atropine and dopamine infusion and underwent definitive therapy with a permanent dual-chamber pacemaker with complete symptom resolution. Diagnostic confounders include convulsive syncope and ictal bradycardia. Syncope may be accompanied by myoclonic jerks (convulsive syncope), but postictal confusion is absent. Bradycardia may be seen during the postictal period (ictal bradycardia syndrome), but protracted sinus dysfunction is not present. Hypoperfusion due to significant SSS triggered seizures in this patient who may have an underlying predisposition.