1/922. Minimally invasive cardiac surgery with surgical ablation of atrial fibrillation. Surgical ablation for atrial fibrillation with mitral valve operations has been often performed in patients who have chronic atrial fibrillation associated with mitral valve disease. We describe a case of the combined operation through a small incision. A 49-year-old woman presented with a 1-month history of left hemiplegia. echocardiography confirmed mitral stenosis and electrocardiogram revealed atrial fibrillation. The duration of the atrial fibrillation before admission was 12 years. Mitral commissurotomy, removal of clots, and surgical ablation for atrial fibrillation was performed through an 8-cm right parasternal incision. The right femoral artery and vein were used for cannulation. Another cannula was inserted into the superior vena cava. The extended use of cryoablation was carried out instead of atriotomy or reanastomosis. The patient was extubated for 5 hours after the operation. atrial fibrillation was converted to a sinus rhythm. On the basis of our experience, this procedure seemed promising. ( info) |
2/922. adenosine-induced atrial pro-arrhythmia in children. adenosine has become the preferred acute treatment for common types of supraventricular tachycardia because of its efficacy and safety. There have been a few reports of serious proarrhythmic events associated with its use, including the induction of atrial fibrillation in adult patients. Three instances of adenosine-induced atrial proarrhythmia (two atrial fibrillation and one atrial flutter) have been observed in children with manifest or concealed wolff-parkinson-white syndrome at the Hospital for Sick Children, Toronto, ontario since 1990, which indicates a previously unreported risk of atrial arrhythmia for children as well. Because adenosine may enhance antegrade bypass tract conduction, its use carries a risk of ventricular acceleration, including progression to ventricular fibrillation. Because of such rare and potentially life-threatening adverse effects, appropriate monitoring and precautions are required during the administration of the drug to children and adults. ( info) |
3/922. A patient with hypertrophic cardiomyopathy accompanied by right ventricular dilation of unknown cause. Hypertrophic cardiomyopathy (HCM) is a disease characterized by an unknown cause of hypertrophy in the left or right ventricle. The dilated phase of HCM shows disease conditions resembling dilated cardiomyopathy, such as ventricular dilation, thin ventricular wall, and reduction of the ejection fraction. A patient presented with left ventricular concentric hypertrophy accompanied by right ventricular dilatation of unknown cause. Right ventricular endomyocardial biopsy specimens showed characteristic myocardial disarray. Therefore, there is the possibility that the patient had right and left ventricular HCM in the process toward the dilated phase, in which dilatation first occurred in the right ventricle. ( info) |
4/922. Impaired cardiac performance relating to delayed left atrial activation after atrial compartment operation for chronic atrial fibrillation. In the presence of a normal atrial systole and optimal AV delay, atrial kick contributes to a significant fraction of the stroke volume. This atrial contribution may be lost during atrial asystole or mismatch in the timing of atrial and ventricular contraction. A patient received atrial compartment operation for his chronic AF. Although the AF was successfully converted to sinus rhythm, the conduction from the right to left atrium was markedly delayed so that the left atrial and ventricular activations occurred almost simultaneously. This delay in left atrial activation resulted in impaired cardiac performance. ( info) |
5/922. TSH-secreting pituitary macroadenoma: rapid tumor shrinkage and recovery from hyperthyroidism with octreotide. A 44-year-old man with atrial fibrillation caused by hyperthyroidism is described. The underlying disease was a TSH-secreting macroadenoma of the pituitary. Treatment with the somatostatin analog octreotide eliminated hyperthyroidism and atrial fibrillation within 4 days and the tumor size diminished substantially within 3 weeks. ( info) |
6/922. ST segment elevation in the right precordial leads induced with class IC antiarrhythmic drugs: insight into the mechanism of brugada syndrome. We evaluated two patients without previous episodes of syncope who showed characteristic ECG changes similar to brugada syndrome following administration of Class IC drugs, flecainide and pilsicainide, but not following Class IA drugs. Patient 1 had frequent episodes of paroxysmal atrial fibrillation resistant to Class IA drugs. After treatment with flecainide, the ECG showed a marked ST elevation in leads V2 and V3, and the coved-type configuration of ST segment in lead V2. A signal-averaged ECG showed late potentials that became more prominent after flecainide. Pilsicainide, a Class IC drug, induced the same ST segment elevation as flecainide, but procainamide did not. Patient 2 also had frequent episodes of paroxysmal atrial fibrillation. Pilsicainide changed atrial fibrillation to atrial flutter with 2:1 ventricular response, and the ECG showed right bundle branch block and a marked coved-type ST elevation in leads V1 and V2. After termination of atrial flutter, ST segment elevation in leads V1 and V2 continued. In this patient, procainamide and quinidine did not induce this type of ECG change. In conclusion, strong Na channel blocking drugs induce ST segment elevation similar to brugada syndrome even in patients without any history of syncope or ventricular fibrillation. ( info) |
7/922. Left ventricular ischemia due to coronary stenosis as an unexpected treatable cause of paroxysmal atrial fibrillation. We present a patient with exercise-induced paroxysmal atrial fibrillation who was eventually scheduled for a Cox-maze operation due to persistence of his complaints of fatigue, impaired exercise tolerance, and predominantly exercise-related irregular palpitations despite treatment with several antiarrhythmic drugs. A preoperative exercise stress test without antiarrhythmic or negative chronotropic drugs, however, showed clear evidence of myocardial ischemia. After coronary angioplasty of a significant stenosis in the left anterior descending artery, there was no recurrence of atrial fibrillation during a follow-up of 7 months. ( info) |
8/922. Thrombotic risk in thalassemic patients. Hemostatic parameters of 495 beta-thalassemic patients (421 with thalassemia major and 74 with thalassemia intermedia) were analyzed, to assess their association with the described thrombophilic condition and to verify the role of additional risk factors (e.g. persistent postsplenectomy thrombocytosis, insulin dependent diabetes mellitus, estrogen-progestin treatment and atrial fibrillation). The prevalence of thromboembolic accidents was 5.2% and in four patients (15.3%) inherited or acquired predisposing defects were recognized. The incidence of thromboembolic events and the associated relative risk due to hemocoagulative abnormalities in these patients are discussed. ( info) |
9/922. Double valve repair and maze procedure for degenerative valvular disease and chronic atrial fibrillation. A 61-year-old male with degenerative aortic valve regurgitation, mitral valve regurgitation and chronic atrial fibrillation underwent a combined reparative procedure consisting of aortic valve repair, mitral valve repair and maze procedure. Surgery was successful and postoperatively the patient is in NYHA class I, without anticoagulation. To the best of our knowledge, this is the first clinical report of this combined reparative surgery. As advances are made in valve repair surgery, it is expected that similar combined procedures will be performed more frequently in future. The benefits of avoiding valve replacement and anticoagulation after such combination treatment is discussed. ( info) |
10/922. Pilsicainide intoxication in a patient with dehydration. An 81-year-old woman developed pilsicainide intoxication associated with dehydration. The patient had been taking pilsicainide (100 mg/day) for 1 year because of paroxysmal atrial fibrillation. Her renal function was within normal limits. One week before admission, she was suffering from pneumonia, and had appetite loss, fever, and severe fatigue. physical examination revealed dehydration. The electrocardiogram (ECG) on admission showed atrioventricular dissociation, idioventricular rhythm with marked QRS widening and QTc prolongation. The plasma concentration of pilsicainide on admission was markedly elevated at 6.2 microg/ml, approximately 6 times the therapeutic range (0.25-1.0 microg/ml). Continuous saline infusion was initiated for the treatment of dehydration,which progressively improved. As a result, sinus rhythm was recovered 2 h after admission, and the QRS and JT intervals gradually normalized. This is an interesting case because the proarrhythmia of pilsicainide was induced by dehydration. ( info) |