Cardioneuroablation for pediatric patients with functional sinus node dysfunction and paroxysmal atrioventricular block

INTRODUCTION

Severe transitory episodes of bradycardia with subsequent syncope in children are common, and generally portend a benign prognosis. Rarely, patients may experience prolonged asystolic episodes secondary to significant sinus pauses (SP) or paroxysmal atrioventricular block (AVB). Cardioneuroablation (CNA) is a catheter-based intervention, used to identify and ablate the epicardial ganglionated plexi (GP), which results in disruption of the vagal-mediated parasympathetic input to the sinus and atrioventricular node.

OBJECTIVE

Describe the methodology and role of CNA for treatment of pediatric patients with functional AVB or SP.

METHODS

This is a single-center, case series study. Patients with SP or AVB, 21 years of age or younger, who underwent CNA between 2015 and 2021 were included. CNA was performed via anatomically guided and high-frequency stimulation methods.

RESULTS

Six patients were included. The median age was 18.9 years (range 12.3-20.9 years), 33% female. Two patients had prolonged SP, two had paroxysmal AVB, and two had both SP and AVB. Four patients had prior syncope. The median longest pause was 8.9 s (range 3.9-16.8) with 11 total documented pauses (range 2-231) during the 6 months pre-CNA. Post-CNA, the median longest pause was 1.3 s (range 0.8-2.2) with one documented SP after termination of atrial tachycardia at the 3-month follow-up. At 6 months, the median longest pause was 1.1 s (0.8-1.3) with 0 documented pauses. No patients had syncope post-CNA.

CONCLUSION

CNA may be an effective alternative to pacemaker implantation in pediatric patients with syncope or significant symptoms secondary to functional SP or AVB.

Resolution of Marked Bradycardia Following Angioplasty

Bradycardia, a condition commonly managed conservatively and, subsequently, with pacemaker implantation presents a unique challenge when coexisting with coronary artery disease (CAD). This case report delves into an unusual scenario where bradycardia and its related symptoms resolved following coronary angioplasty. Our goal is to contribute valuable data to the argument for a comprehensive evaluation of bradycardic patients for underlying CAD prior to considering pacemaker implantation. This approach aims to prevent unnecessary pacemaker implantations and offers insights into the optimal management of patients presenting with both arrhythmia and CAD. The unusual resolution of bradycardia in this case underscores the importance of considering CAD as a possible underlying factor in bradycardic patients, prompting a reevaluation of conventional treatment protocols. By documenting this exceptional case, the authors advocate a more nuanced and individualized treatment strategy in the management of bradycardia, emphasizing the need to assess and address CAD as part of the diagnostic workup.

Heart Block and Sinus Pause Following Abdominal Surgery: A Case Requiring Temporary Pacemaker Insertion

This case report presents the clinical course of a 70-year-old female with a history of hypertension who developed sinus pauses following abdominal surgery, ultimately requiring the placement of a pacemaker. The patient initially presented with altered mental status preceded by abdominal pain, which progressed to confusion and obtundation. Examination revealed signs of toxicity, tachycardia, tachypnea, and a distended abdomen with absent bowel sounds. A computed tomography (CT) scan of the abdomen indicated closed-loop small bowel obstruction with free air and ascites. The patient underwent exploratory laparotomy, revealing purulent fluid and a necrotic, perforated appendix, leading to appendectomy and peritoneal irrigation. Subsequent surgeries addressed the coagulative necrosis of the omentum and wound closure. During the recovery period, the patient exhibited bradycardia with sinus pauses, including episodes of complete heart block. Cardiology consultation attributed this to increased parasympathetic tone following surgery and recommended the placement of a temporary transvenous pacemaker. As the patient's condition improved, the sinus pacing function progressively returned, leading to the removal of the pacemaker. This case underscores the potential development of sinus pauses after abdominal surgery and highlights the importance of prompt recognition, appropriate management, and collaboration between surgical and cardiology teams to ensure patient recovery.

Translational implications of bradyarrhythmia in hibernating brown bears

The brown bear Ursus arctos undergoes exceptional physiological adaptions during annual hibernation that minimize energy consumption, including profound decrease in heart rate, cardiac output, and respiratory rate. These changes are completely reversible after the bears reenter into the active state in spring. In this case report, we show episodes of sinus arrest in a hibernating Scandinavian brown bear and in humans, recorded by implantable loop recorders and discuss the possible underlying mechanisms. Lessons learned from cardiac adaptations in hibernating bears might prove useful in the treatment of patients with sinus node dysfunction.

Post Total Thyroidectomy Deglutition Syncope

Deglutition syncope is a form of situational syncope where patients develop presyncope or syncope during swallowing. This condition has been observed to occur most commonly in patients with prior gastroesophageal conditions. Our patient developed deglutition syncope that started to occur a few weeks after undergoing a total thyroidectomy. The patient was found to have paroxysmal atrioventricular (AV) block, with up to 5.1 seconds of asystole during swallowing, manifested with episodes of dizziness and lightheadedness. A barium swallow test revealed normal peristalsis and no evidence of dysmotility. The patient underwent placement of a dual chamber pacemaker, and the syncopal episodes resolved. Interrogation of the pacemaker showed no recorded abnormal events.

Lyme Carditis Manifesting as Wenckebach Heart Block

Lyme disease caused by Borrelia burgdorferi is a multisystem disease and can lead to Lyme carditis. The most common presentation of Lyme carditis is conduction system disturbances such as atrioventricular (AV) block. A 72-year-old male with a past medical history of gastroesophageal reflux disease (GERD) and prostate cancer presented with chest tightness, lightheadedness, and presyncope. During hospitalization, he developed bradycardia with heart rates ranging between 30 and 40 beats per minute and Wenckebach heart block. Lyme serology was consistent with a recent Lyme infection. He was treated with antibiotics and was eventually discharged home without requiring pacemaker implantation.

Sinus pause during nerve integrity monitoring tube insertion following anesthetic induction with a low-dose neuromuscular blocking agent: A CARE-compliant case report

RATIONALE

Nerve integrity monitoring (NIM) tubes are commonly used in thyroid surgery to prevent recurrent laryngeal nerve injury. To achieve the optimal electromyographic signal for NIM as intraoperative neural monitoring (IONM), the neuromuscular blocking agent (NMBA) dose should be low. The use of a low-dose NMBA increases the anesthetic and analgesic agent dose required to attenuate the laryngeal reflex during intubation. In addition, since the NMBA onset time is delayed, depending on the situation, anesthesia may become excessively deep or shallow before intubation.

PATIENTS CONCERN

A 51-year-old woman scheduled for thyroid lobectomy received 0.3 mg/kg of rocuronium. Three minutes later, when the NIM tube was inserted through the vocal cord, the patient's heart rate (HR) was undetectable for 2 seconds.

DIAGNOSIS

We suspected that the use of a high-dose anesthetic agent and remifentanil or the laryngocardiac reflex induced the sinus pause.

INTERVENTIONS

To maintain the anesthetic depth, we administered 6 vol% of desflurane. Because the patient's systolic blood pressure was 70 mmHg and HR was 30 beats/min, we discontinued the remifentanil infusion and administered 8 mg of ephedrine.

OUTCOMES

The patient's vital signs recovered to normal levels. Subsequently, there were no episodes of bradycardia or arrhythmia.

CONCLUSION

Sinus pause or severe bradycardia may occur due to the laryngocardiac reflex or the administration of a high-dose anesthetic and analgesic agent during tracheal intubation in patients who received a low-dose NMBA for IONM induction using an NIM tube. Anesthesiologists should be aware of these risks and take precautions to maintain adequate anesthesia, be prepared to administer vasoactive drugs to increase the blood pressure and HR if needed, and, if possible, intravenously administer lidocaine to attenuate the laryngeal reflex during intubation.

Severe OSA Leading to Long Pauses in 24-h Holter ECG Reversed with CPAP

INTRODUCTION

Sleep-related problems like sleep apnea are increasing tremendously mostly owing to the disordered lifestyle the present generation is leading which is added like a topping on the base of obesity and metabolic syndrome. The burden on the society is huge taking into consideration the work-time loss and health-related financial issues arising out of these sleep disorders with obstructive sleep apnea (OSA) leading the way. Early diagnosis can prevent several complications of OSA. Cardiovascular diseases, including various arrhythmias, arising due to OSA, are described previously.

CASE PRESENTATION

Herein, an interesting case of OSA, whose pacemaker installation to rectify the long pause could be avoided by simple correction of his OSA using continuous positive airway pressure, is presented. This 49-year-old male patient was diagnosed with severe OSA by using polysomnography and all his significant sinus pauses (highest one with 7.8 sec) during holter ECG monitoring were found to be occurring at night and correcting his OSA with continuous positive airway pressure (CPAP) treatment reverted all those sinus pauses and the need for any further intervention with pacemaker was discarded.

DISCUSSION

OSA is caused by either partial or complete obstruction of the upper airway, and there is the simultaneously attenuated upper airway dilator muscle tone while the patient is sleeping. The gold standard test designed for the assessment of OSA is polysomnography, as approved by the American Academy of Sleep Medicine and CPAP has been found to be universally beneficial in treating OSA related complications. Physiologically, the ACC/AHA guidelines recommend pacing only in patients with prolonged asymptomatic pauses occurring during wakefulness. This case report proved the above mentioned claim of CPAP treatment.

Transient Asymptomatic Sinus Bradycardia and Sinus Pauses with Bevacizumab: Case Report and Literature Review

Systemic side effects of anti-cancer therapy remain a major limiting factor for patients, even with targeted therapy. Bevacizumab is an example of targeted cancer therapy which targets the vascular endothelial growth factor receptor (VEGFR) that has been approved for the treatment of various cancers and has been evaluated in metastatic urothelial carcinoma (MUC). We report a case of MUC on bevacizumab containing regimen who developed temporary asymptomatic sinus bradycardia with sinus pauses. That adverse event was thought to be related to the bevacizumab in her cancer regimen. Her Holter monitoring recording for a total duration of 28 days and 14 h after discharge did not show recurrence of sinus pauses. This case indicates the necessity for observation for the cardiac conduction defects as side effects in patients receiving bevacizumab, especially since they might be asymptomatic and transient. 

Takotsubo Cardiomyopathy Presenting with Sinoatrial Disease: A Rare Presentation

Takotsubo cardiomyopathy (TCM), or apical ballooning syndrome, is a distinct nonischemic cardiomyopathy mimicking acute coronary syndrome. A 76-year-old female presented with ST elevation in the inferior lead and a troponin level of 0.81 ng/dL. An immediate coronary angiography showed non-obstructive coronary artery disease. A subsequent ventriculogram and echocardiogram showed anteroapical and distal inferior wall hypokinesis suggestive of TCM. Despite therapy with beta blocker, she was observed to have two significant sinus pauses, one eight-second, and a second 29-second pause. An urgent transvenous pacemaker was put in place and later followed by a permanent pacemaker. The patient was discharged on carvedilol and losartan. Although other arrhythmias such as complete heart block, torsades, and ventricular arrhythmias have been commonly reported, the association of TCM with recurrent sinus arrest has rarely been reported in the literature. The occurrence observed in this case implies that patients with TCM should be monitored closely for arrhythmias, and, if such a condition is identified, planning for permanent pacemaker implantation should be started early enough to avoid recurrent life-threatening episodes.

Sinus pause in association with Lyme carditis

Lyme disease is the most prevalent tick-borne disease in the United States. It is caused by the spirochete Borrelia burgdorferi. Cardiac involvement is seen in 4% to 10% of patients with Lyme disease. The principal manifestation of Lyme carditis is self-limited conduction system disease, with predominant involvement of the atrioventricular node. On rare occasions, Lyme carditis patients present with other conduction system disorders such as bundle branch block, intraventricular conduction delay, and supraventricular or ventricular tachycardia. We report the unusual case of a 59-year-old man who presented with new-onset symptomatic sinus pauses one month after hiking in upstate New York. To our knowledge, this is the first case report from North America that describes the relationship between symptomatic sinus pause and Lyme carditis.