B-PO03-199 SINUS NODE DYSFUNCTION AFTER SURGERY FOR CONGENITAL HEART DISEASE: INCIDENCE AND IMPACT ON RECOVERY

Introduction: Ventricular dyssynchrony induced by ventricular pacing (VP) may predispose patients (pts) to congestive heart failure. The detrimental effects of VP are directly related to the cumulative percentage of VP (Cum%VP). Managed ventricular pacing (MVP, Medtronic) is a novel pacing algorithm developed to minimize unnecessary VP by uncoupling atrial pacing from VP. The use, efficacy, and safety of MVP in pediatrics pts and pts with congenital heart disease (CHD) have not been described. Methods: A multicenter review evaluated all pediatric pts < 22 years old and older pts with CHD that had an implanted device using an MVP algorithm. Primary outcome variables were Cum%VP and adverse events. A subgroup analysis evaluated pts that had a DDD/R pacemaker prior to MVP device with similar low pacing rate and compared Cum%VP before and after initiation of MVP, using Wilcoxon signed-rank test. Results: 62 patients from 6 centers were included for the review (see table ). Mean age at MVP device implant was 21.5 ± 9.6 years (range 7–51). 63% of pts had CHD. With MVP device, mean Cum%VP was 4.3 ± 14.6% (range 0 – 83.7). By pacing indication, Cum%VP was 2.9 ± 6.5% in pts with sinus node dysfunction (n = 24), 34.8 ± 41.3% in pts with atrioventricular (AV) block (n = 5), and 0.6 ± 1.0% in pts with an ICD (n = 33). 11 patients were eligible for subgroup analysis. With DDD/R pacing, mean low rate was 64 ppm and mean paced/sensed AV intervals were 251 and 241 ms. With MVP, mean low rate was 63 ppm and mean paced/sensed AV intervals were 193 and 166 ms. Compared to DDD/R, Cum%VP significantly decreased with MVP (67.1 ± 29.4 vs. 9.2 ± 24.8%; p < 0.005). One MVP-related adverse event occurred: a pt with intermittent AV block had symptoms with nonconducted atrial beats and was reprogrammed to DDD. Conclusions: MVP can be used safely and can significantly reduce unnecessary ventricular pacing in pediatric pts and pts with CHD. MVP should be considered when choosing a pacing mode for this pt population.

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CONGENITAL HEART DISEASE: INCIDENCE IN THE FIRST YEAR OF LIFE

American Journal of Epidemiology ◽

10.1093/oxfordjournals.aje.a114978 ◽

1988 ◽

Vol 128 (2) ◽

pp. 381-388 ◽

Cited By ~ 84

Author(s):

RALPH G. GRABITZ ◽

MICHEL R. JOFFRES ◽

RUTH L. COLLINS-NAKAI

Keyword(s):

Congenital Heart Disease ◽

Heart Disease ◽

Congenital Heart ◽

Disease Incidence ◽

First Year ◽

First Year Of Life

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Altered autonomic cardiac regulation in individuals with Down syndrome

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00560.2005 ◽

2005 ◽

Vol 289 (6) ◽

pp. H2387-H2391 ◽

Cited By ~ 38

Author(s):

Ferdinando Iellamo ◽

Alberto Galante ◽

Jacopo M. Legramante ◽

Maria Enrichetta Lippi ◽

Claudia Condoluci ◽

...

Keyword(s):

Congenital Heart Disease ◽

Down Syndrome ◽

Heart Disease ◽

Congenital Heart ◽

Sinus Node ◽

Control Subjects ◽

Arterial Blood ◽

Cardiac Regulation ◽

Autonomic Cardiac Regulation ◽

And Control

We tested the hypothesis that individuals with Down syndrome, but without congenital heart disease, exhibit altered autonomic cardiac regulation. Ten subjects with Down syndrome (DS) and ten gender-and age-matched healthy control subjects were studied at rest and during active orthostatism, which induces reciprocal changes in sympathetic and parasympathetic traffic to the heart. Autoregressive power spectral analysis was used to investigate R-R interval variability. Baroreflex modulation of sinus node was assessed by the spontaneous baroreflex sequences method. No significant differences between DS and control subjects were observed in arterial blood pressure at rest or in response to standing. Also, R-R interval did not differ at rest. R-R interval decreased significantly less during standing in DS vs. control subjects. Low-frequency (LFNU) and high-frequency (HFNU) (both expressed in normalized units) components of R-R interval variability did not differ between DS and control subjects at rest. During standing, significant increase in LFNU and decrease in HFNU were observed in control subjects but not in DS subjects. Baroreflex sensitivity (BRS) did not differ between DS and control subjects at rest and underwent significant decrease on going from supine to upright in both groups. However, BRS was greater in DS vs. control subjects during standing. These data indicate that subjects with DS exhibit reduced HR response to orthostatic stress associated with blunted sympathetic activation and vagal withdrawal and with a lesser reduction in BRS in response to active orthostatism. These findings suggest overall impairment in autonomic cardiac regulation in DS and may help to explain the chronotropic incompetence typically reported during exercise in subjects with DS without congenital heart disease.

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