Fetal Arrhythmias - kusm
Transcription
Fetal Arrhythmias - kusm
Fetal Arrhythmias Dawn Boender, PGY3 Overview Tachyarrhythmias Bradyarrhythmias Fetal Arrhythmias 1% of fetuses 75% extrasystoles 15% tachyarrhythmias 9% bradyarrhythmia Tachyarrhythmias Tachyarrhythmia Differential Diagnosis Premature Atrial Contractions Supraventricular Tachycardia Atrial Flutter Sinus Tachycardia Ventricular Tachycardia Tachyarrhythmia Making Brief the diagnosis review… Tachyarrhythmia Making the diagnosis M-mode Align cursor through one atria and ventricle Visualizes relationship Distinguishes type of arrhythmias Tachyarrhythmia Making the diagnosis Pulse wave doppler Cursor placed between mitral and aortic valve Flow disturbances (regurgitation) Pulse wave doppler Premature Atrial Contractions Most common fetal arrhythmia 18-24 wga Dx: Doppler inflow/outflow or left ventricle or M-mode Aggrevating factors Spontaneous resolution 1% progression to SVT Premature Atrial Contractions Premature Atrial Contractions Premature Atrial Contractions Management in pregnancy No treatment needed Evaluation with fetal echocardiogram Doppler auscultation q1-4 weeks F/u US Resume routine care after 2-3 weeks Supraventricular Tachycardia SVT Most common sustained tachycardia FHR 240-280 bpm Accessory pathway vs autonomic Typically structurally normal Congenital heart disease up to 5-10% Dx: 2D, Doppler, M-mode 1:1 conduction Supraventricular Tachycardia Supraventricular Tachycardia Management of Pregnancy Controversial D/C precipitating factors Continuously monitor 8-24 hours Treat if… Structurally abnormal heart >33% present Hydrops Controversial: delivery after 32-34wga Consider vaginal delivery Supraventricular Tachycardia Management Digoxin Load with 0.5mg IV q6-8h until: <25% tachycardia or decreased hydrops Therapeutic Toxicity PO of Pregnancy administration BID-QID Digoxin level, BMP, EKG, cardiologist consult Second-line agents Atrial Flutter Sustained tachycardia FHR: Atrial 300-500 bpm Ventricular <100-300 bpm Often 2:1 or 3:1 conduction Structurally normal Structural heart disease up to 20% Atrial Flutter Atrial Flutter Management Digoxin Sotalol Propranolol in Pregnancy Sinus Tachycardia FHR 180-200 1:1 conduction Causes: Maternal pyrexia Stimulants Maternal thyrotoxicosis Fetal systemic disease Anemia, distress, infections Ventricular Tachycardia FHR: 180-300 bpm Not well tolerated Structural abnormalities, tumors, long QT NOT a 1:1 ratio Ventricular Tachycardia Ventricular Tachycardia Management in pregnancy NO DIGOXIN Oral propranolol, mexiletine, sotalol, amiodarone Umbilical vein - lidocaine Tachyarrhythmia Outcomes 50% relapse after birth Medical therapy Neurological outcomes Recurrence risk Bradyarrhythmias Bradyarrhythmias Differential diagnosis Sinus bradycardia Atrial bradycardia Blocked atrial bigeminy Atrial flutter with high-degree block Complete heart block Transient responses Sinus Bradycardia 1:1 conduction ratio Fetal distress Long QT syndrome Risk for ventricular tachycardia Atrial Bradycardia Accessory atrial pacemaker Absent sinus node Associated with polysplenia Atrial bigeminy Atria alternates sinus beats with PACs PACs during refractory period (AV node) Ventricular rate Regular ½ atrial rate Avoid caffeine, decongestants, tobacco Atrial Flutter Atrial rate: 300-500 BPM High degree AV block Results in fetal bradycardia Constant arrhythmia Treatment: digoxin vs sotalol Complete Heart Block (CHB) Most common FHR: 40-70 bpm Atrial rate normal No conduction, resulting in ventricular rate May find 1st or 2nd degree block Incidence: 1/20,000 live births Complete Heart Block (CHB) Complete Heart Block (CHB) Causes Maternal anti-Ro (SSA) or anti-La (SSB) antibodies Associated with SLE, Sjogren’s syndrome, connective tissue disorders Antibodies damage fetal AV node Suspected cofactor 20-24wga Complete Heart Block (CHB) Causes Structural heart disease L-looped ventricles AV septal defect Associated with polysplenia Poor survival outcome Complete Heart Block (CHB) Management in pregnancy Rheumatologic evaluation CPS, Fetal echo Doppler of umbilical artery (limited) Serial growth US Cardiothoracic ratio NST not helpful FHR < 60, up to twice weekly US Complete Heart Block (CHB) Management in pregnancy Dexamethasone Betamimetic agents IVIG Plasmapheresis In utero heart pacing: experimental Complete Heart Block (CHB) Delivery Cesarean Consider if hemodynamic compromise Nonimmune hydrops Ventricular rate <55bpm AV valve insufficiency Pediatric cardiologist and surgeon available Outcomes Up to 25% develop nonimmune hydrops CHB with structural abnormality – poor outcome 14% survival Early delivery for pacemaker <20% survival CHB with <55bpm 15% survival 20% survival Neonatal lupus erythematous in 90% of SSA and SSB 90% survival after neonatal period Plaquenil – consider in future pregnancies References Bianci et al. (2010). Tachyarrhythmias in Fetology: Diagnosis and Management of the Fetal Patient. McGraw Hill Medical. 313-319. Bianci et al. (2010). Bradyarrhythmias in Fetology: Diagnosis and Management of the Fetal Patient. McGraw Hill Medical. 313-319. 320-327. Creasy & Resnik (2009). Fetal Cardiac Malformations and Arrhythmias in Maternal Fetal Medicine Principles and Practice, 6th edition. Saunders Elsevier. 336-341. Simpson (2006). Fetal arrhythmias. Ultrasound Obstet Gynecol. 27:599-606. Srinivasan, Strasburger (2008). Overview of fetal arrhythmias. Current Opinions in Pediatrics. 20(5):522-531. Strasburger, Cheulkar, Wichman (2007). Perinatal Arrhythmias: Diagnosis and Management. Clinical Perinatology. 34(4):627. Questions?