Cardiac device implantation in Fabry disease: A retrospective monocentric study

The incidence and predictive factors of arrhythmias and/or conduction abnormalities (ACAs) requiring cardiac device (CD) implantation are poorly characterized in Fabry disease (FD). The aim of our retrospective study was to determine the prevalence, incidence, and factors associated with ACA requiring CD implantation in a monocentric cohort of patients with confirmed FD who were followed up in a department of internal medicine and reference center for FD.Forty-nine patients (20M, 29F) were included. Nine patients (4M, 5F; 18%) had at least one episode of ACA leading to device therapy. Six patients (4M/2F) required a pacemaker (PM) for sinus node dysfunction (n = 4) or atrioventricular disease (n = 2). One female patient required an internal cardioverter-defibrillator (ICD) to prevent sudden cardiac death because of nonsustained ventricular tachycardia (nSVT). One female patient required PM-ICD for sinus node dysfunction and nSVT. One patient underwent CD implantation before the diagnosis of FD. The annual rate of CD implantation was estimated at 1.90 per 100 person years. On univariate analysis at the end of the follow-up period, the factors associated with ACAs requiring CD implantation were as follows: delayed diagnosis of FD, delayed initiation of enzyme replacement therapy, age at the last follow-up visit, and severe multiorgan phenotype (hypertrophic cardiomyopathy, chronic kidney disease, and/or sensorineural hearing loss). On multivariate analysis, age at diagnosis of FD and age at the last follow-up visit were independently associated with an increased risk of ACAs requiring CD (P < 0.05).Considering the high frequency of ACAs requiring CD implantation and the risk of sudden death in patients with FD, regular monitoring is mandatory, especially in patients with a late diagnosis of FD and/or with a severe phenotype. Regular Holter ECGs, therapeutic education of patients, and deliverance of an emergency card including a phenotype summary are crucial in the care of FD patients.Available guidelines for device therapy and the efficacy of enzyme replacement therapy for arrhythmias or conduction abnormalities are discussed.

Partial rupture of the tricuspid valve after extraction of permanent pacemaker leads: detection by transesophageal echocardiography

Traumatic lesions of the tricuspid valve complicating pacemaker lead extractions appear to be rare. We report two cases of partial rupture of the tricuspid valve, following apparently uneventful extraction of permanent ventricular leads, resulting in severe regurgitation and, in one case, chronic heart failure. TEE was useful to identify the traumatic mechanism of tricuspid regurgitation (TR) and the extent of valvular lesions in these patients. Such etiology should be suspected, and TEE performed, in patients developing TR or heart failure late after lead extraction.

Electrophysiological study of intravenous pinaverium bromide in cardiology

Pinaverium bromide is a musculotropic spasmolytic agent which acts by inhibiting transmembrane calcium movements, an effect similar to that of verapamil. Because of this, an investigation was carried out to see if it had any electrophysiological effects in patients with various cardiac disorders. In an open study, 10 patients received 2 mg pinaverium bromide intravenously. In a double-blind study, 10 patients received 4 mg pinaverium bromide intravenously and 10 patients placebo. Patients included those with either normal or pathological basal conduction, such as bundle-branch block and 1st degree atrioventricular block. Measurements were made of electrophysiological parameters before and 10 minutes after injection. The results showed that neither of the two doses of pinaverium bromide had any effect on atrial excitability, sino-atrial conduction, node and trunk atrioventricular conduction or on intraventricular conduction. No significant difference was seen in comparison with placebo. Pinaverium bromide had no anti-arrhythmic properties in these studies. Local, cardiac and general clinical tolerability was good in all patients.

[Early interruption of antiarrhythmia treatment in the acute phase of infarction complicated by ventricular arrhythmia]

18 patients with myocardial infarction complicated by severe ventricular arrhythmias (polymorphic VEBs or bigeminy = 5; VT = 11; VF = 2) were treated with antiarrhythmics which were stopped after 24 hours (intravenous infusion of mexiletine 0.5 mg/kg/hr after a loading dose). This treatment resulted in one failure (recurrent VF) and 17 successes, after increasing the dose in 3 cases of VT. After stopping treatment, 72% of patients had no further arrhythmia. 5 cases had recurrent VT within 72 hours, which was controlled by oral mexiletine in 4 cases. The ejection fraction was significantly decreased in the group with recurrent VT. Plasma assays were of little help. Stopping the antiarrhythmic treatment after 24 hours does not therefore present any particular risks and can be proposed even in cases with severe arrhythmias.

Multiple acyl-CoA dehydrogenase deficiency occurring in pregnancy and caused by a defect in riboflavin metabolism in the mother. Study of a kindred with seven deaths in infancy: Value of riboflavin therapy in preventing this syndrome

Seven infants in one kindred died: one was stillborn; the others, who were floppy at birth and were breast-fed, developed a disorder with the odor of sweaty feet and died in early infancy. In two further pregnancies, 3-hydroxvisovaleric, glutaric, and C6-C10-dicarboxylic acids were demonstrated in the mother's urine during the seventh month. Riboflavin therapy in the last trimester of pregnancy and a riboflavin-rich diet given the infants prevented this syndrome. The presence of abnormal erythrocyte glutathione-reductase activity in the mother while she excreted normal amounts of riboflavin in her urine indicates a probable disorder of riboflavin metabolism resulting in multiple acyl-CoA dehydrogenase deficiency.