Prospective Evaluation of Fetuses With Autoimmune-Associated Congenital Heart Block Followed in the PR Interval and Dexamethasone Evaluation (PRIDE) Study

• Published in: The American journal of cardiology Vol. 103; no. 8; pp. 1102 - 1106
• Main Authors: Friedman, Deborah M., MD, Kim, Mimi Y., ScD, Copel, Joshua A., MD, Llanos, Carolina, MD, Davis, Claudine, BS, Buyon, Jill P., MD
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 15-04-2009; Elsevier; Elsevier Limited
• Subjects: Adolescent; Adult; Autoantigens - immunology; Autoimmune diseases; Autoimmune Diseases - complications; Autoimmune Diseases - immunology; Biological and medical sciences; Cardiac dysrhythmias; Cardiology; Cardiology. Vascular system; Cardiovascular; Cardiovascular disease; Dexamethasone - therapeutic use; Drugs; Female; Fetal Diseases; Fetuses; Glucocorticoids - therapeutic use; Heart; Heart Block - congenital; Heart Block - drug therapy; Heart Block - immunology; Humans; Medical sciences; Peptide Fragments - immunology; Pregnancy; Prospective Studies; Ribonucleoproteins - immunology; Young Adult; Autoimmunity; Evaluation; Dexamethasone; Arrhythmia; Congenital; PR interval; Cardiovascular disease; Conduction disorder; Prospective; Heart disease; Heart block; Fetus; Circulatory system; Cardiology
• ISSN: 0002-9149; 1879-1913
• DOI: 10.1016/j.amjcard.2008.12.027

We evaluated the efficacy of dexamethasone (DEX) in anti-SSA/Ro–exposed fetuses newly diagnosed with congenital heart block. Previous use of DEX has been anecdotal with varying reports of therapeutic benefit. This was a multicenter, open-label, nonrandomized study involving 30 pregnancies treated with DEX (22 with third-degree block, 6 with second-degree block, 2 with first-degree block) and 10 untreated (9 with third-degree block, 1 with first-degree block). Initial median ventricular rates, age at diagnosis, and degree of cardiac dysfunction were similar between groups. Six deaths occurred in the DEX group. There was no reversal of third-degree block with therapy or spontaneously. In fetuses treated with DEX, 1/6 with second-degree block progressed to third-degree block and 3 remained in second-degree block (postnatally 1 paced, 2 progressed to third degree); 2 reverted to normal sinus rhythm (NSR; postnatally 1 progressed to second degree). DEX reversed the 2 fetuses with first-degree block to NSR by 7 days with no regression at discontinuation. Absent DEX, the 1 with first-degree block detected at 38 weeks had NSR at birth (overall stability or improvement in 4 of 8 in the DEX group vs 1 of 1 in the non-DEX group). Median gestational birth age was 37 weeks in the DEX group versus 38 weeks in the non-DEX group (p = 0.019). Prematurity and small size for gestational age were restricted to the DEX group. Pacemaker use and growth parameters at birth and 1 year were similar between groups. In conclusion, these data confirm the irreversibility of third-degree block and progression of second- to third-degree block despite DEX. A potential benefit of DEX in reversing first- or second-degree block was supported in rare cases but should be weighed against potential steroid side effects such as growth restriction.