ABSTRACT
OBJECTIVES: This study assessed the coexistence of intra-atrial re-entrant tachycardia (IART) and isthmus-dependent atrial flutter (IDAF) in patients presenting with supraventricular tachyarrhythmias after surgical correction of congenital heart disease (CHD). BACKGROUND: In patients with CHD, atrial tachyarrhythmias may result from IART or IDAF. The frequency with which IART and IDAF coexist is not well defined. METHODS: Both IDAF and IART were diagnosed in 16 consecutive patients using standard criteria and entrainment mapping. Seven patients had classic atrial flutter morphology on surface electrocardiogram (ECG), whereas nine had atypical morphology. RESULTS: A total of 24 circuits were identified. Three patients had IDAF only, five had IART only, seven had both, and one had a low right atrial wall tachycardia that could not be entrained. Twenty-two different reentry circuits were ablated. Successful ablation was accomplished in 13 of 14 (93%) IART and 9 of 10 (90%) IDAF circuits. There was one IART recurrence. The slow conduction zone involved the region of the right atriotomy scar in 12 of 14 (86%) IART circuits. No procedural complications and no further recurrences were seen after a mean follow-up of 24 months. CONCLUSIONS: Both IDAF and IART are the most common mechanisms of atrial re-entrant tachyarrhythmias in patients with surgically corrected CHD, and they frequently coexist. The surface ECG is a poor tool for identifying patients with coexistent arrhythmias. The majority of IART circuits involve the lateral right atrium and may be successfully ablated by creating a lesion extending to the inferior vena cava.
Subject(s)
Atrial Flutter/diagnosis , Heart Defects, Congenital/complications , Tachycardia, Supraventricular/diagnosis , Adolescent , Adult , Aged , Atrial Flutter/complications , Atrial Flutter/epidemiology , Catheter Ablation , Child , Electrocardiography , Electrophysiologic Techniques, Cardiac , Female , Fluoroscopy , Follow-Up Studies , Heart Defects, Congenital/diagnostic imaging , Heart Defects, Congenital/surgery , Humans , Male , Middle Aged , Prevalence , Recurrence , Tachycardia, Supraventricular/complications , Tachycardia, Supraventricular/epidemiologySubject(s)
Cardiovascular Diseases/diagnosis , Catheter Ablation/standards , Clinical Competence/standards , Electric Countershock/standards , Electrophysiologic Techniques, Cardiac/standards , American Heart Association , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/surgery , Education, Professional/standards , Electrophysiologic Techniques, Cardiac/trends , Humans , Professional Competence/standards , Teaching/standards , United StatesSubject(s)
Anti-Arrhythmia Agents/administration & dosage , Anti-Arrhythmia Agents/pharmacokinetics , Atrial Fibrillation/drug therapy , Phenethylamines/administration & dosage , Phenethylamines/pharmacokinetics , Sulfonamides/administration & dosage , Sulfonamides/pharmacokinetics , Action Potentials/drug effects , Administration, Oral , Animals , Anti-Arrhythmia Agents/adverse effects , Atrial Flutter/drug therapy , Controlled Clinical Trials as Topic , Disease Models, Animal , Dose-Response Relationship, Drug , Electrocardiography/drug effects , Electrophysiologic Techniques, Cardiac , Humans , Phenethylamines/adverse effects , Potassium/metabolism , Potassium Channel Blockers , Potassium Channels/metabolism , Reaction Time/drug effects , Sulfonamides/adverse effects , Treatment Outcome , Ventricular Fibrillation/drug therapyABSTRACT
Clinical cardiac electrophysiology is a relatively new discipline, heavily dependent upon new technology that is often expensive. In cardiac pacing, no effective alternative to permanent pacing usually exists for patients with Class I indications, so cost-reduction strategies involve appropriate selection and utilization of hardware and facilities. Cost-effective utilization of radiofrequency ablation and implantable cardioverter-defibrillators requires that these techniques be compared with alternative therapies, usually antiarrhythmic drugs. Both ablation and defibrillator implantation can be shown to be cost effective in selected populations, but a cost-conscious approach to procedures and patient selection can make them cost effective in a broad range of patients.
Subject(s)
Arrhythmias, Cardiac/therapy , Cardiac Pacing, Artificial/economics , Catheter Ablation/economics , Defibrillators, Implantable/economics , Arrhythmias, Cardiac/economics , Cost-Benefit Analysis , Humans , Tachycardia, Supraventricular/economics , Tachycardia, Supraventricular/therapyABSTRACT
Of 77 patients hospitalized for unstable angina pectoris and failure of oral, dermal, or intravenous nitrates and/or beta blockade, 81 percent with negligible or single-vessel disease and 55 percent with two- or three-vessel disease showed response (p less than 0.05) to nifedipine therapy. Patients with either S-T elevation or no change during pain responded better (31 of 45) than those with any S-T depression (16 of 32; p less than 0.05). Patients with negligible or single-vessel disease had a higher prevalence of S-T elevation (13 of 16) than patients with two- or three-vessel disease (15 of 31; p = 0.004). S-T motion did not predict response in patients with two- or three-vessel disease, but did predict response in patients with negligible or single-vessel disease. On follow-up study at 9 +/- 8 (range one to 33) months, 39 of 42 who had shown response were free from pain. Three died from infarction without unstable angina. (range one to 33) months, 39 of 42 who had shown response were free from pain. Three died from infarction without unstable angina. Five who showed response had elective bypass surgery. The addition of nifedipine abolished or reduced pain episodes by more than 50 percent in 61 percent of patients with refractory unstable angina pectoris. Patients with negligible or single-vessel disease with S-T elevation benefit most. In patients with two- or three-vessel disease, the type of S-T motion did not predict response. Follow-up of all those with response indicated sustained amelioration by nifedipine therapy. Failure of nifedipine therapy should not be accepted until a dose of 120 mg per day has been achieved, or until intolerable side effects appear.