Case report: high-dose carvedilol as a potential key drug for arrhythmias in histiocytoid cardiomyopathy

Background

Histiocytoid cardiomyopathy is a rare infancy cardiac disorder manifesting as severe cardiac arrhythmias or dilated cardiomyopathy. There is no specific treatment for these arrhythmias. This is the first report of infantile histiocytoid cardiomyopathy whose refractory ventricular arrhythmias were successfully controlled by high-dose carvedilol.

Case summary

A 4-month-old girl presented with asystole, and recurrent ventricular tachycardias. From the histological findings and clinical symptoms, she was diagnosed as histiocytoid cardiomyopathy. Sedatives were the most effective therapy for her arrhythmia, but the cardiac sympathetic denervation was not effective enough. Finally, her ventricular arrhythmias were controlled with high-dose carvedilol, and she was discharged on hospitalization Day 393.

Discussion

Carvedilol is the only beta blocker that directly acts on the ryanodine receptor (RyR2) and inhibits store-overload-induced Ca2+ release (SOICR) in myocardium at high dosage. The arrhythmias did not disappear with bisoprolol, landiolol, or verapamil, but high-dose carvedilol was effective. This clinical course suggested that the arrhythmias in histiocytoid cardiomyopathy might be related with SOICR. High-dose carvedilol might be a key drug for patients with histiocytoid cardiomyopathy.

Extracorporeal life support as bridge to recovery in yew poisoning: case reports and literature review

Aims

This short communication aims to review the treatment of cardiogenic shock in patients with yew poisoning based on two case reports from our institution, focusing on the use of extracorporeal life support (ECLS).

Methods and results

We report two cases of Taxus baccata poisoning treated with ECLS at our institution and review the literature based on a search in PubMed and Google Scholar on the topic of yew poisoning and ECLS. All cases were combined for analysis of demographics, ECLS therapy, and outcome. Case 1: A 35‐year‐old woman developed polymorphic ventricular tachycardia followed by cardiovascular arrest 5 h after orally ingesting a handful of yew needles. Successful resuscitation required ECLS for 72 h due to ongoing cardiac arrhythmias and cardiogenic shock. The patient left the hospital without neurological sequelae after 10 days. Case 2: A 30‐year‐old woman developed refractory cardiac arrhythmias and circulatory arrest. Resuscitation included ECLS for 71 h. T. baccata needles found by gastroscopy confirmed the diagnosis. The patient had no neurologic deficits and was transferred to psychiatry after 11 days. Review of the literature: Nine case reports were found and analysed along with our two cases. Five out of the 11 (45%) patients were female. Median (range) age was 28 (19–46) years. T. baccata needles were ingested with a suicidal intention in all patients. Median (range) duration of ECLS was 70 h (24–120 h). Eight (73%) patients had full neurological recovery.

Conclusions

Yew poisoning is a differential diagnosis in young psychiatric patients presenting with polymorphic ventricular tachycardia and cardiogenic shock. A characteristic cardiac contraction pattern in echocardiography may present a diagnostic clue. The early use of ECLS is a valuable bridge to recovery in most of these patients.