Severe Oleander Poisoning Presenting with Hyperkalaemia and Unusual Electrocardiographic Changes

Background: Hyperkalaemia in oleander (Nerium oleander) poisoning has been associated with a poor prognosis. Different electrocardiographic (ECG) presentations are possible because of vagotonia and hyperkalaemia. Methods/Results: We report a series of three cases of oleander poisoning in which ECG showed unusual hyperkalaemia features, such as bradyarrhythmia, sinoatrial block, atrioventricular block and junctional rhythm. Conclusions: If arterial blood gas analysis or laboratory values indicate hyperkalaemia in oleander poisoning, the hyperkalaemia should be treated immediately, even if the ECG does not show typical hyperkalaemia features.

Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers

Introduction: The cardiac electrical conduction system is very sensitive to hypoglycemia and hypoxia, and the consequence may be brady-arrythmias. Weddell seals endure brady-arrythmias during their dives when desaturating to 3.2 kPa and elite breath-hold-divers (BHD), who share metabolic and cardiovascular adaptions including bradycardia with diving mammals, endure similar desaturation during maximum apnea. We hypothesized that hypoxia causes brady-arrythmias during maximum apnea in elite BHD. Hence, this study aimed to define the arterial blood glucose (Glu), peripheral saturation (SAT), heart rhythm (HR), and mean arterial blood pressure (MAP) of elite BHD during maximum apneas.Methods: HR was monitored with Direct-Current-Pads/ECG-lead-II and MAP and Glu from a radial arterial-catheter in nine BHD performing an immersed and head-down maximal static pool apnea after three warm-up apneas. SAT was monitored with a sensor on the neck of the subjects. On a separate day, a 12-lead-ECG-monitored maximum static apnea was repeated dry (n = 6).Results: During pool apnea of maximum duration (385 ± 70 s), SAT decreased from 99.6 ± 0.5 to 58.5 ± 5.5% (∼PaO2 4.8 ± 1.5 kPa, P < 0.001), while Glu increased from 5.8 ± 0.2 to 6.2 ± 0.2 mmol/l (P = 0.009). MAP increased from 103 ± 4 to 155 ± 6 mm Hg (P < 0.005). HR decreased to 46 ± 10 from 86 ± 14 beats/minute (P < 0.001). HR and MAP were unchanged after 3–4 min of apnea. During dry apnea (378 ± 31 s), HR decreased from 55 ± 4 to 40 ± 3 beats/minute (P = 0.031). Atrioventricular dissociation and junctional rhythm were observed both during pool and dry apneas.Conclusion: Our findings contrast with previous studies concluding that Glu decreases during apnea diving. We conclude during maximum apnea in elite BHD that (1) the diving reflex is maximized after 3–4 min, (2) increasing Glu may indicate lactate metabolism in accordance with our previous results, and (3) extreme hypoxia rather than hypoglycemia causes brady-arrythmias in elite BHD similar to diving mammals.

522 A strange case of bradycardia in a 38-year-old woman postpartum

Methods and results A 38-year-old woman at her 4th day postpartum from a twin pregnancy, presented to the Emergency Room with general malaise, headache, and dyspnoea. Her symptoms had started to show 2 days prior to her ER admission and were worsened by bilateral pitting oedema. In particular they had started when she was administered cabergoline to suppress lactation. Her blood pressure was elevated (160/80 mmHg) and her heart rate was 40 b.p.m. On examination she was oriented in time and space. Her laboratory exams showed anaemia (Hb 8.8 g/dl), with negative D-dimer and troponin. She had no urine proteinuria, which allowed pre-eclampsia to be excluded from the diagnostic hypotheses. A 12-lead ECG was performed and showed junctional rhythm with isorhythmic dissociation at 40 b.p.m. She was admitted to the cardiology ward for diagnostic workup. Her echocardiogram showed no structural alteration and preserved ejection fraction. A cardiac magnetic resonance confirmed the absence of structural alterations or late gadolinium enhancement. During her hospital stay, sinus rhythm was spontaneously restored at 42 b.p.m.; in addition to this, restoration of sinus rhythm, although bradycardic, was associated to the resolution on both her symptoms and of her pitting oedema. She was discharged with a diagnosis of bradycardia secondary to carbegoline use. Her Holter ECG, performed 7 days after discharge, showed sinus bradycardia with occasional isorhythmic dissociation. Conclusions Cabergoline is an ergot-derived dopamine agonist usually used in the treatment of Parkinson’s disease. It acts selectively on D2 receptors. It can be associated to orthostatic hypotension, cardiac valvular fibrosis, and angina pectoris. No cases of cabergoline-induced bradycardia can be currently found in literature; however, a similar effect was seen with the use of methylergometrine in a women during her post-partum period. Furthermore, studies on mice have shown that ergot derivatives may cause reduction of heart rate. It therefore seems possible that in our case, the use of cabergoline induced the patient’s bradyarrhythmia.

Esophageal Rupture Presenting with ST Segment Elevation and Junctional Rhythm Mimicking Acute Myocardial Infarction

Esophageal rupture is a rare but potentially fatal cause of chest pain. The presentation is variable and can mimic other conditions such as aortic dissection, pulmonary embolism, and myocardial infarction (MI). A 71-year-old male with a history of coronary artery disease presented to the ED with complaints of acute chest pain and respiratory distress. Over the next 48 hours, the patient developed dynamic ST segment changes on surface electrocardiogram mimicking an inferolateral ST segment elevation MI accompanied by a junctional rhythm. Curiously, his cardiac enzymes remained negative during this time, but his clinical status continued to deteriorate. A subsequent CT scan demonstrated a lower esophageal rupture, and the patient underwent successful endoscopic stenting. While rare, prompt recognition of esophageal rupture is imperative to improving morbidity and mortality. While esophageal rupture has been noted to cause ST segment elevation before, this appears to be the first case associated with a junctional rhythm.

Six-Year Follow-Up Outcomes of Catheter Ablation of Para-Hisian Accessory Pathways

Background: Ablation of para-hisian accessory pathways (APs) remains challenging due to anatomic characteristics, and a few studies have focused on the causes for recurrence of radiofrequency ablation of para-hisian APs.Objective: This retrospective single center study aimed to explore the risk factors for recurrence of para-hisian APs.Methods: One hundred thirteen patients who had para-hisian AP with an acute success were enrolled in the study. In the 6-year follow-up, 15 cases had a recurrent para-hisian AP. Therefore, 98 patients were classified into the success group, while 15 patients were classified into the recurrence group. Demographic and ablation characteristics were analyzed.Results: Gender difference was similar in two groups. The median age was 36.2 years old and was younger in the recurrence group. Maximum ablation power was significantly higher in the success group (29 ± 7.5 vs. 22.9 ± 7.8, p < 0.01). Ablation time of final target sites was found to be markedly higher in the success group (123.4 ± 53.1 vs. 86.7 ± 58.3, p < 0.05). Ablation time <60 s was detected in 12 (12.2%) cases in the success group and 7 (46.7%) cases in the recurrence group (p < 0.01). Occurrence of junctional rhythm was significantly higher in the recurrence group (25.5% vs. 53.3%, p < 0.05). No severe conduction block, no pacemaker implantation, and no stroke were reported. Junctional rhythm during ablation (OR = 3.833, 95% CI 1.083–13.572, p = 0.037) and ablation time <60 s (OR = 5.487, 95% CI 1.411–21.340, p = 0.014) were independent risk factors for the recurrence of para-hisian AP.Conclusions: With careful and accurate mapping, it is relatively safe to ablate para-hisian AP. If possible, proper extension of ablation time could reduce the recurrence rate of para-hisian APs.

11-year follow-up outcomes of catheter ablation of para-hisian accessory pathways

Funding Acknowledgements Type of funding sources: None. Background Ablation of para-hisian accessory pathways (APs) remains challenging due to anatomic characteristics and few studies have focused on the causes for recurrence of radiofrequency ablation of para-hisian APs. Objective This retrospective single center study was aimed to explore the risk factors for recurrence of para-hisian APs. Methods 113 patients who had a para-hisian AP with an acute success were enrolled in the study. In the 11-year follow-up, 15 cases had a recurrent para-hisian AP. Therefore 98 patients were classified into success group while 15 patients were classified into recurrence group. Demographic and ablation characteristics were analyzed. Results Gender difference was similar in two groups. The median age was 36.2 years old and was younger in recurrence group. Maximum ablation power was significantly higher in success group (29 ± 7.5 vs 22.9 ± 7.8, p < 0.01). Ablation time of final target sites was found to be markedly higher in success group (123.4 ± 53.1 vs 86.7 ± 58.3, p < 0.05). Ablation time less than 60 seconds was detected in 12 (12.2%) cases in success group and 7 (46.7%) cases in recurrence group (p < 0.01). Occurrence of junctional rhythm was significantly higher in recurrence group (25.5% vs 53.3%, p < 0.05). No severe conduction block, no pacemaker implantation and no stroke were reported. Junctional rhythm during ablation (OR = 3.833, 95%CI 1.083-13.572, p = 0.037) and ablation time <60s (OR = 5.487, 95%CI 1.411-21.340, p = 0.014) were independent risk factors for the recurrence of para-hisian AP. Conclusions Considering the long-term safety of ablation of para-hisian AP, proper extension of ablation time and increase of ablation power could be applied during operation.