199: Prevalence and significance of stroke among patients with paroxysmal supraventricular tachycardia

Abstract

The risk of atrial fibrillation (AF) in patients with paroxysmal supraventricular tachycardia (SVT) is well-known. AF is a cause of embolic event and a risk of stroke in patients with SVT can be expected. The purpose of the study was to assess the prevalence of unexplained stroke in patients presenting with SVT and to look for the risk factors. Electrophysiological study (EPS) was performed in 1379 patients without anterograde conduction through accessory pathway (AP) for SVT. Clinical and electrophysiological data were collected. Stroke was noted in 38 patients (group I) (prevalence 2.8%). 1341 patients had no stroke (group II). 1) Clinical data: Group I was older than group II (62±13 vs 49±19 years) (p<0.0002). Associated heart disease (14/38, 37% vs 139/1341, 10%)(p<0.0001), AF history (4/38, 10.5%, 32/1341, 2%, p<0.002) were more frequent in group I than in group II. Male gender was similar in both groups. 2) Electrophysiological data: SVT mechanism was similar: AV re-entrant tachycardia in a concealed AP was noted in 4 group I patients (10.5%) and 247 group II patients (18%)(NS). Signs of atrial vulnerability were as frequent in both groups. 3) Follow-up (mean 3±3 years): Adverse events (AE) occurred in 102 patients: 3 group II patients presented a stroke; AF occurred in 8 group I patients (21%), 62 group II patients (5%)(p<0.0001); 3 group I patients (8%), 26 group II patients (2%) died from cardiovascular death (p<0.01). SVT ablation was performed in 65 of 102 patients (64%) with AE (AF or death), 790 of 1277 patients without AE (62%)(NS). Age (p=0.001), prior AF (p=0.001) were the 2 independent risk factors of stroke at multivariate analysis stroke. Adjusted on age, heart disease was not significantly associated with stroke. Unexplained stroke was a rare event in patients with paroxysmal SVT (2.8%). Old age, and AF history were the only independent significant factors associated with the history of stroke in these patients. They had a risk of severe adverse events during the follow-up as spontaneous AF (21%) or death (8%). SVT ablation did not reduce the risk of new stroke, spontaneous AF or death.