A case report of deglutition triggered atrial fibrillation in a patient with Laing distal myopathy

Abstract

Background: Deglutition-induced atrial fibrillation is a rare clinical entity with a reported prevalence of 0.6%. Laing distal myopathy is a rare autosomal dominant muscular dystrophy that is the result of mutations within the slow skeletal muscle fibre myosin heavy chain gene (MYH7). Atrial fibrillation has not been previously reported in patients with Laing distal myopathy. We describe the first reported case of deglutition triggered atrial fibrillation in a female with a history of Laing distal myopathy.

Case summary: A 44-year-old female with a history of Laing distal myopathy diagnosed at age 32, began experiencing intermittent episodes of pre-syncope and palpitations which occurred after deglutition with food. An ambulatory 30-day patient triggered event monitor recorded episodes of atrial fibrillation with rapid ventricular response. Family history was significant for Laing distal myopathy, atrial fibrillation, as well as sudden cardiac death. Laboratory data, transthoracic echocardiogram, cardiac magnetic resonance imaging, and an exercise treadmill SPECT Imaging stress test were normal. An oesophagram revealed a mild oesophageal dysmotility with no other abnormalities. She was started on flecainide 50 mg p.o. every 8 h and verapamil 40 mg p.o. every 8 h with no further episodes of atrial fibrillation.

Discussion: Given the strong genetic component of this myopathy, one could postulate as to a possible genetic component in the development of atrial fibrillation in our patient. Although we cannot make definite correlation between deglutition-induced atrial fibrillation and Laing myopathy, it is important to report this unusual association which has not been described before.

Keywords: Case report; Deglutition triggered atrial fibrillation; Flecainide and non-dihydropyridine calcium channel blockers; Laing distal myopathy; Wide-complex tachycardia.

Figure 1

Ambulatory patient triggered cardiac event strip demonstrating atrial fibrillation with rapid ventricular response at 170 b.p.m. Event was triggered after deglutition.

Figure 2

Ambulatory patient triggered cardiac event which reveals sinus rhythm with 75 b.p.m. followed by 13 beats of wide-complex tachycardia at 242 b.p.m. Event was triggered after deglutition.