Title : Case of tachycardia induced cardiomyopathy during pregnancy: clinical presentation and management
Abstract:
Cardiomyopathy is a known complication of tachyarrhythmias and carries a relatively favourable prognosis when rate control or reversal of the underlying cause is achieved. However, in pregnancy, it may be difficult to distinguish other more sinister causes of cardiomyopathy from tachyarrhythmia-induced cardiomyopathy. Furthermore, tachycardia is often overlooked in pregnant people and may be taken as a physiological response to volume changes in late pregnancy. Treatment options are limited based on teratogenicity and fetal cardiotoxicity depending on gestational age.
Case 1. A 28 year old G2P0010 with remote history of spontaneous abortion at approx 5 weeks of pregnancy presented for routine prenatal care at 33 weeks EGA. The pregnancy was complicated by COVID-19 infection at 16 weeks EGA, treated with casirivimab-imdevimab, and benign thrombocytopenia. On presentation to the outpatient office, she was asymptomatic but heart rate was noted at approximately 150 BPM and irregular. ECG was performed and was consistent with atrial multifocal tachycardia. Fetal heart rate was 140 BPM. Patient was started on labetalol 50 mg daily and was referred to cardiology for urgent consultation. Echocardiogram was performed and showed dilated left ventricular cavity with moderately reduced ejection fraction of 40%. No previous echocardiogram was available for comparison. Dose of labetalol was increased to 50 mg twice daily. Though she frequently spontaneously converted to sinus rhythm, especially with vagal manoeuvres, she was unable to maintain sinus rhythm. She was admitted to the maternal-fetal medicine service with family medicine, cardiology, and electrophysiology in consultation. While on continuous electronic fetal monitoring, she was loaded with digoxin but atrial tachycardia persisted despite therapeutic levels of digoxin. She was transitioned from labetalol and digoxin to flecainide and metoprolol after which sinus rhythm was maintained. Repeat echocardiogram at 36 weeks gestation revealed improvement in EF to 50% and ECG revealed normal sinus rhythm. Labor was induced at 39 weeks' gestation with continued flecainide and metoprolol intrapartum; she delivered a healthy male infant via normal spontaneous vaginal delivery. Flecainide was discontinued and metoprolol was continued postpartum. Three days postpartum, the patient presented to the ED with biliary colic and was found to have reverted to atrial tachycardia. She was switched from metoprolol to flecainide and converted to sinus rhythm prior to discharge. She presented for routine postpartum follow-up to the family medicine office on postpartum day 15 and EKG again revealed atrial tachycardia. She was restarted on metoprolol and thereafter maintained sinus rhythm. Repeat echocardiogram and electrophysiological evaluation is planned for six weeks postpartum.
What will audience learn from your presentation?
Tachycardia during pregnancy is common due to volume changes and distinguishing between physiological and pathological causes can be a challenge for clinicians. In particular, tachyarrhythmias may be easily overlooked.
Persistent tachycardia during pregnancy requires multispecialty evaluation and tight coordination between patient and physician.
When tachycardia or arrythmia is diagnosed during pregnancy, echocardiogram may be necessary to evaluate left ventricular systolic function and rule out structural abnormalities
Medication choice is limited due to pregnancy, but several agents are known to be safe and effective in pregnancy throughout gestation. We will discuss the clinical decision-making process in evaluation and management of tachycardia and arrhythmia in pregnancy.
The role of continuity, consultation, and collaboration in obstetric care when transitioning between low and high risk providers, especially late in gestation.
