Prolonged Sinus Pauses Revealing A Paroxysmal Extreme Pain Disorder: Is It A Frequent Situation? A Case Report

Abstract

Title: Paroxysmal extreme pain disorder (PEPD) is an autosomal dominant painful neuropathy with many, but not all, cases linked to gain-of-function mutations in SCN9A which encodes voltage-gated sodium channel Na. 1.7. It is a very rare condition featured by flushing of the lower half of the body and excruciating burning pain caused by any stimulus below the waist or in the perianal region. PEPD may be associated with cardiovascular instability, especially prolonged sinus pauses, and thus has anesthetic implications. Pacemaker implantation is the alternative therapeutic option, but its indications have not been clarified yet.Background: This condition is well described in neurological literature, but to our knowledge, this is the first case report of a patient with paroxysmal extreme pain disorder with prolonged sinus pauses requiring anesthesia for an epicardial pacemaker even with the perioperative risk of the pathology. This clinical observation can help for a better management and understanding of the cardiac risk complications of PEPD especially for an infant whose diagnostic is frequently made at the stage of complication This clinical observation can put the item on the necessity of establishing recommendations for management of cardiac complications during PEPD. Case report:We extensively searched the literature on cardiac pacing in patients with PEPD and we described a new case of a 9 month old infant who was admitted in the emergency department for an episode of malaise apnea and hemifacial cyanosis relevant to PEPD. The neurologic exploration was normal. The diagnostic was confirmed by genetic study. The 24 hours recording demonstrated long pauses of 15 seconds during the crisis justifying the implantation of epicardial pacemaker without peri-operatory complications due to the high anesthetic risk of this pathology. IntroductionParoxysmal extreme pain disorder (PEPD) is an autosomal dominant painful neuropathy with many, but not all, cases linked to gain-of-function mutations in SCN9A which encodes voltage-gated sodium channel Na. 1.7. The paper should be of interest because this clinical observation can put the item on the severity of the cardiac risk complications of this disease especially for an infant whose diagnostic is frequently made at the stage of complication. This clinical observation can help for a better understanding of the management of anesthetic process Because of the potential for cardiovascular instability ObservationA 9-month-old infant was brought to the emergency department after an episode of malaise and hemifacial cyanosis. Her parent reported that the crisis was triggered by crying. The infant had vegetative manifestations like hemifacial redness, snorkeling and sweats with foam at the lips, motor manifestations like rubbing feet with reduced consciousness. So the infant turned blue around the lips and began gasping for air. During this time, her eyes "rolled back", and she did not interact with her parents. There were no clonic movements, and she did not respond to ...

Paroxysmal extreme pain disorder: A very rare genetic aetiology of syncope with bizarre flushing in an infant

“…Dramatic TLoC with asystole, vasodilatation (flushing) and/or cyanosis (breath‐holding) is common due to pain‐ or distress‐induced excessive vagal discharge and can lead to pacemaker implantation. Perhaps only by addressing the asystolic part of this mechanism in our patient, effective pacing by itself did not hinder further paroxysmal episodes of flushing and TLoC, but potentially life‐threatening complications of asystole were prevented 3,7 . By adding a more causal treatment, to stabilise the defective sodium channel and thereby prevent the accentuation of painful stimuli, a marked improvement was achieved.…”

“…Some cases of PEPD are associated with cardiovascular instability leading to prolonged sinus pauses. The inheritance pattern is autosomal dominant with complete penetrance and limited variability of phenotypic expression within families 1–3 …”

“…Perhaps only by addressing the asystolic part of this mechanism in our patient, effective pacing by itself did not hinder further paroxysmal episodes of flushing and TLoC, but potentially life-threatening complications of asystole were prevented. 3,7 By adding a more causal treatment, to stabilise the defective sodium channel and thereby prevent the accentuation of painful stimuli, a marked improvement was achieved. In contrast, some authors published that effective pacing alone prevented further syncopes even without medication and that the symptoms of patients with prolonged sinus pauses were not relieved by carbamazepine treatment alone and pacemaker implantation should be considered.…”

“…By adding a more causal treatment, to stabilise the defective sodium channel and thereby prevent the accentuation of painful stimuli, a marked improvement was achieved. In contrast, some authors published that effective pacing alone prevented further syncopes even without medication and that the symptoms of patients with prolonged sinus pauses were not relieved by carbamazepine treatment alone and pacemaker implantation should be considered 3 . This means that the pathophysiology behind the symptoms of PEPD is complex and the response to carbamazepine treatment and/or pacing can vary.…”

“…The inheritance pattern is autosomal dominant with complete penetrance and limited variability of phenotypic expression within families. [1][2][3] PEPD (formerly known as familial rectal pain syndrome) is a member of heterogenous Hereditary sensory (and autonomic) neuropathies family: heterozygous gain of function mutations of the SCN9A gene on the second chromosome encoding Na v 1.7 voltage-gated sodium channel are responsible for PEPD via excessive signalization, but can also cause small nerve fibre neuropathy or primary (inherited) erythromelalgia. Homozygous loss of function mutations of the same gene cause congenital insensitivity to pain.…”