Ventricular fibrillation treated by cryotherapy to the right ventricular outflow tract: a case report

Abstract

BackgroundArrhythmias originating from the right ventricular outflow tract are generally considered benign but cases of cardiac arrest have been described, usually associated with polymorphic ventricular tachycardia or extrasystoles with short coupling intervals.Case presentationWe report the case of a 54-year-old Caucasian woman with symptomatic right ventricular outflow tract arrhythmias without structural heart disease who suffered a ventricular fibrillation arrest without prior malignant clinical features. Cryoablation was performed and an implantable cardioverter defibrillator was implanted. She has since been free of arrhythmia for 7 years and has asked that the implantable cardioverter defibrillator not be replaced when the battery becomes depleted.ConclusionsAlthough usually benign, right ventricular outflow tract tachycardia can be life-threatening. Even the most malignant cases can be cured by ablation.

Stylistic features of case reports as a genre of medical discourse

“… Case presentation: “We report the case of a 54-year-old Caucasian woman with symptomatic right ventricular outflow tract arrhythmias without structural heart disease who suffered a ventricular fibrillation arrest without prior malignant clinical features”. Discussion: “At the time of presentation, she was taking no medication (…) She was discharged on a slow-release preparation of verapamil 240 mg daily for control of symptoms (…) One month later, our patient was readmitted after suffering an out-of-hospital VF cardiac arrest from which she was successfully resuscitated (…) On recovery, our patient accepted our recommendation that she undergo ablation of the focus of ventricular ectopy but she refused implantable cardioverter defibrillator (ICD) therapy” [ 7 ]. …”

“…Hence, MCRs are notable for their use of active sentences in the simple past tense (309 cases) [ 3 , 5 – 18 ]: “We maintained anesthesia with inhaled desflurane at 5% and intravenously administered remifentanil at 0.2 μg/kg/min in a fraction of inspired oxygen of 0.45 (…) At that moment, we administered 20 mg ephedrine, 300 μg phenylephrine, and 0.03 μg/kg/min norepinephrine to maintain adequate blood pressure (…) We did not detect any problems with his respiratory parameters (…) His systolic blood pressure remained at 40 mmHg for 10 min; we performed chest compressions to maintain his blood pressure” [ 5 ]; “We did not find cases with such an evolution in the literature, but we found some cases of spontaneous expulsion of ileal lipoma per rectum” [ 6 ]; “We found electrogram amplitude to be normal throughout the right ventricle (…) In this case we used cryoablation to avoid the pain associated with radiofrequency delivery” [ 7 ]; “An extraoral examination revealed a diffuse swelling of her left nasal alar base without tenderness” [ 8 ]; “Two patients with EHPVO presented with micrognathia, restricted mouth openings, and facial asymmetry” [ 9 ]; “Brain magnetic resonance imaging (MRI) did not identify any abnormalities, but an ophthalmic examination revealed vertical supranuclear gaze palsy (VSGP), and analysis of peripheral blood and bone marrow biopsies identified vacuolated histiocytes” [ 10 ]; “…we considered electroconvulsive therapy; clinicians may opt for electroconvulsive therapy at an earlier stage in similar psychiatric emergencies (…) We hypothesized that our patient’s poor clinical response was from a genetic polymorphism in the drug-metabolizing activity of cytochrome P450 enzymes” [ 11 ].…”

“…The present perfect tense is generally used to render the author’s reflections on the problem in a broader context (for instance, the results of other research, which occur primarily in the “ Background ” section of MCRs). The research has identified 180 cases of present perfect constructions (103 active and 77 passive sentences): “There have been a number of previous reports of CVC malpositioning in the internal mammary vein”; “Numerous complications of central venous catheterization have been reported ” [ 13 ]; “Other studies have demonstrated the ability of ablation to prevent recurrence of VF in patients with a structurally normal heart, but these studies also have been of small patient cohorts followed only for a few years” [ 7 ]; “Few cases of bilateral nasoalveolar cysts have been described” [ 8 ].…”

“…At the same time, our research has demonstrated the relatively seldom use of the future tense in MCRs (a total of 16 cases: 13 active and 3 passive sentences). Occasionally, the authors use it in the “ Conclusions ” section to provide a perspective for further research or a prognosis: “An ultrasound-guided approach rather than the use of a landmark technique to insert CVC will help ” [ 13 ]; “Patients will tolerate the procedure with adequate airway preparation using topical anesthesia” [ 9 ]; “Until the effectiveness of ablation for the prevention of VF has been confirmed in a large cohort of such patients followed for a substantial duration, we will continue to recommend ICD therapy for most survivors of VF arrest even if ablation is also performed” [ 7 ]; “The tooth will preserve the remaining alveolar ridge and help the adolescent psychologically” [ 12 ].…”

“…The use of the present simple tense is also comparatively infrequent and it is generally used only in the opening section of MCRs (23 cases in the analyzed discourse): “We report a rare case of a CVC tip malpositioned in the right internal mammary artery (IMA)” [ 13 ]; “ We describe the case of a 30-year-old man from the north of Morocco with no medical or surgical history and no family history of rectal disease” [ 6 ]; “ We describe a case in which RVOT ectopy was complicated by ventricular fibrillation (VF) arrest despite the absence of any of the recognized risk factor for cardiac arrest and despite an apparently positive response to pharmacological therapy” [ 7 ]; “Here, we present two cases where difficult intubation was anticipated, and in which, despite trying various devices to visualize and secure the airway, only the use of a Macintosh blade proved successful” [ 9 ]; “ We report a case of an acute psychotic relapse in response to polydrug use most notable for multiple recent binges of crystal methamphetamine” [ 11 ].…”