ABSTRACT
The purpose of this study was to evaluate the safety and efficacy of radiofrequency (RF) ablation of typical atrial flutter by using an 8-mm electrode catheter and a 100-W RF power generator. A limitation of previous trials of catheter ablation of atrial flutter is that the data were not collected as part of a prospective multicenter clinical trial. The study results associated catheter ablation of typical atrial flutter in a cohort of 150 patients with an 88% acute efficacy rate. At 6-month follow-up, recurrent typical atrial flutter was observed in 13% of patients. Of the 12 patients with typical atrial flutter recurrence, 4 were symptomatic and 8 were asymptomatic. Procedure duration was a significant predictor of typical atrial flutter recurrence. The 12-month rate for development of atrial fibrillation was 30%. Catheter ablation of atrial flutter was associated with significant improvements in 5 of 8 domains of the Short Form 36 Survey (quality of life) and significant decreases in 13 of the 16 symptoms of the Symptom Checklist. The device- or procedure-related complication rate was 2.7%. Skin burns occurred at the dispersive pad site due to stronger RF power in 3 patients. Use of a dual dispersive pad system mitigated this problem. Thus, the results of this study associated catheter ablation of atrial flutter with high acute efficacy, a small risk of recurrent atrial flutter, and an important risk of atrial fibrillation during follow-up.
Subject(s)
Atrial Flutter/surgery , Catheter Ablation/instrumentation , Aged , Atrial Fibrillation/diagnosis , Atrial Fibrillation/physiopathology , Atrial Flutter/diagnosis , Atrial Flutter/physiopathology , Cohort Studies , Electrocardiography , Equipment Safety , Female , Follow-Up Studies , Heart Atria/physiopathology , Heart Atria/surgery , Humans , Male , Middle Aged , Prospective Studies , Quality of Life , RecurrenceABSTRACT
This preliminary experimental study demonstrates the potential usefulness of harmonic power Doppler imaging in producing left ventricular myocardial opacification and demonstrating intramyocardial coronary vessels during contrast echocardiography using Levovist, a saccharide-based contrast agent. The contrast effect was most dramatic when a vasodilator such as dipyridamole or nitroglycerin was used in conjunction with contrast injections of Levovist. No significant myocardial opacification was noted with B-mode harmonic imaging alone.
ABSTRACT
Utilizing a new echocardiographic system, intramyocardial coronary arteries could be demonstrated by color Doppler in a small number of open chest animals. Both intravenous and intracoronary injections of a contrast agent (Levovist) resulted in significant enhancement of color flow signals with an increase in the length, width, and the number of these vessels. Similar results were obtained with intravenous infusion and direct intracoronary injections of a vasodilator (adenosine). (ECHOCARDIOGRAPHY, Volume 13, November 1996)
