Effects of cardiac sympathetic innervation on regional wall motion abnormality in patients with long QT syndrome. Issue 3 (1st March 2000)

• Record Type: Journal Article
• Authors: Yamanari, H; Nakayama, K; Morita, H; Miyazi, K; Fukushima, K; Matsubara, H; Emori, T; Ohe, T
• Is Part Of: Heart. Volume 83:Issue 3(2000)
• Page Start: 295
• Page End: 300
• Publication Date: 2000-03-01
• Subjects: long QT syndrome -- sympathetic innervation -- regional wall motion; Heart -- Diseases -- Treatment -- Periodicals; Cardiology -- Periodicals; 616.12
• DOI: 10.1136/heart.83.3.295
• Languages: English
• ISSNs: 1355-6037

Abstract

Abstract : AIM: To assess the spatial relation between regional cardiac sympathetic innervation and regional ventricular repolarisation indicated by ventricular wall motion abnormality in patients with congenital long QT syndrome. DESIGN: Regional percentage uptake and washout rate of 123 I metaiodobenzylguanidine (MIBG) were measured to assess cardiac sympathetic innervation in septum, anterior wall, lateral wall, and posterior wall. Left ventricular short axis images on echocardiography were digitised to reconstruct digitised M mode echocardiograms, from which left ventricular wall thickness curves were obtained. The wall thickening time (ThT) was defined as the period in which the instantaneous wall thickness exceeded 90% of the maximum wall thickness. The ThT was measured from the ventricular wall thickness curve at the same segments where regional percentage uptake and washout rate of 123 I MIBG were measured. PATIENTS: Seven patients with long QT syndrome. RESULTS: The regional washout rate (mean (SD)) of 123 I MIBG in patients with long QT syndrome was greater in the segments with decreased percentage uptake of 123 I MIBG than in those without (17.4 (10.6)% v 9.7 (16.5)%, p < 0.03). ThT in segments both with and without decreased percentage uptake of 123 I MIBG was longer than in control subjects (p < 0.0001). ThT was longer in the segments with decreased percentage uptake of 123 I MIBG than in those without (199 (70) ms v 150 (66) ms, p = 0.0018). CONCLUSIONS: Activation of regional cardiac sympathetic terminals is likely to participate in additional regional prolongation of ventricular repolarisation in patients with long QT syndrome.