Intermittent right bundle branch block in a child with familial mediterranean fever

Abstract

Complete right bundle branch block (RBBB) results when normal electrical activity in the His-Purkinje system is interrupted. The most common cause of RBBB is surgical closure of ventricular septal defects, especially in tetralogy of Fallot [1]. Rare cases of isolated, familial RBBB have also been reported [2].Although a large number of intermittent left bundle branch block (LBBB) cases commonly associated with coronary heart disease have been reported in adults, a very small number of intermittent RBBB cases have been reported [3,4]. Unlike adults, pediatric intermittent RBBB cases have not been reported until now. Herein, is presented the first pediatric case of intermittent RBBB in an asymptomatic 8 year old male patient with familial mediterranean fever (FMF). This is the first pediatric case in literature.An 8-year-old boy with FMF was referred for cardiological evaluation, because of heart murmur. When he was 4 years old, he was diagnosed as having FMF according to the clinical findings and heterozygote mutation (M694V). At that time colchicine (0.5 mg) was administered twice a day and he was completely symptom-free for 4 years. On physical examination, general condition was good and his vital signs including a blood pressure 88/58 mmHg, heart rate (HR) 88 bpm, respiratory rate 19 bpm and a temperature 36.5°C were normal. On cardiac examination, the first heart sound and the second heart sound was normal, and no murmur was heard. Laboratory tests were as follows: white blood cell: 4.66 × 10 3 /µ/L, hemoglobin: 13.2 g/dL, platelets: 191 × 10 3 /mm 3 , hepatic, renal and thyroid function tests were normal. Among acute phase reactants, erythrocyte sedimentation rate (ESR) was found to be 12 mm/h and C-reactive protein (CRP) was found to be 0.24 mg/L. Serum amyloid A (SAA) (0.1 mg/dL) and troponin I (0.00 ng/mL) were all within normal limits. On electrocardiogram, it was observed that the normal QRS complexes were followed by the characteristic pattern of complete RBBB. Wide and slurred S in leads I, II, III, aVF, V4-V6, wide and slurred R waves in leads aVR, V1, and V2 were observed. When the HR increased above 85 bpm, the RBBB appeared (tachycardia dependent block or acceleration-dependent block) ( Fig. 1, left side A, B, C). In continuous 24-h ambulatory 3-lead Holter monitoring revealing a narrow QRS complex was observed during the night and all the following day (HR < 85 bpm) whereas during the HR-accelerated (HR > 85 bpm) period, the terminal portion of the QRS complex slurred was observed (RBBB morphology). While in the provocation test with exercise, normal QRS complex was seen at the beginning of exercise in accordance with findings in Holter, when HR increased to 85 bpm RBBB morphology appeared (Fig. 1, right side A, B, C). Both telecardiography and echocardiography results were normal. With these findings intermittent RBBB was diagnosed and because the patient had no complaints, he was admitted to follow-up in the outpatient clinic. Intermittent RBBB persisted at 6 month follow-up.The criteria for com...

Deep Dive Into Familial Mediterranean Fever in a Child Without Fever

“…Incidentally, it was discovered soon after the initial workup that our patient also had added heart sounds, who was later diagnosed to have pericardial effusion. Abukhalaf and Ceylan et al [13,14] also reported cardiac complications among their patients, namely cardiac amyloidosis and right bundle branch block, respectively. Despite the differences in age groups, clinical presentations, family history, or laboratory results, colchicine remains the first-line treatment modality for a majority of the tabulated patients, with documented recovery.…”

“…Incidentally, it was discovered soon after the initial workup that our patient also had added heart sounds, who was later diagnosed to have pericardial effusion. Abukhalaf and Ceylan et al [ 13 , 14 ] also reported cardiac complications among their patients, namely cardiac amyloidosis and right bundle branch block, respectively.…”

“…Despite the differences in age groups, clinical presentations, family history, or laboratory results, colchicine remains the first-line treatment modality for a majority of the tabulated patients, with documented recovery. However, Ceylan et al point out an unprecedented view of FMF, where colchicine may exacerbate pre-existing cardiac conditions [ 14 ]. Even though the presentation was an isolated incident, it is pivotal to monitor colchicine during and post-administration on a regular basis.…”