Ductal spasm during performance of transcatheter ductal occlusion.

OBJECTIVES: Transcatheter patent ductus arteriosus (PDA) occlusion is a staple of pediatric catheterization laboratories. We present the phenomenon of significant PDA spasm to prevent failure to occlude a hemodynamically significant duct.
BACKGROUND: Transcatheter techniques have evolved, allowing safe and effective occlusion of PDAs in younger and smaller patients. Neonatal care is evolving with increasing survival at younger gestational ages. Premature infants often have PDAs, so the proportion of formerly premature children referred for transcatheter ductal occlusion will likely rise.
METHODS: We reviewed all transcatheter PDA occlusions performed at our institution since 2001 (N = 331). Retrospective data included: gestational age, age at catheterization, precatheterization echocardiographic parameters, PDA size (after spasm relief), device specifications, and most recent follow-up data.
RESULTS: Seven cases were identified. Median age was 12 months, median gestational age was 28 weeks. All were born prematurely. All PDAs were restrictive and six had left-heart volume overload. All patients were examined by the interventional cardiologist and had ductal murmurs. When reauscultated (three of seven), murmurs were absent during spasm. Once spasm relieved, PDA diameters ranged from 1.5 to 8 (median 2) mm. All patients accommodated a 6-mm-or larger-Amplatzer device. No significant complications occurred and all patients were well at follow-up.
CONCLUSIONS: Ductal spasm occurs during transcatheter occlusion and may be an unrecognized cause of procedural failure. The phenomenon seems to occur in children born prematurely, and can occur after infancy. Loss of a continuous murmur confirms the diagnosis. Care should be taken to avoid device under-sizing when spasm occurs.