Franco Humar

Lone atrial fibrillation : Prognostic differences between paroxysmal and chronic forms after 10 years of follow-up

BACKGROUND Lone atrial fibrillation (LAF) is defined by the presence of atrial fibrillation unassociated with other evidence of organic heart disease. There are conflicting data concerning the prognostic importance, rate of embolic complications, and survival in subjects affected by this arrhythmia. METHODS AND RESULTS One hundred forty-five patients younger than 50 years at the time of the first diagnosis were identified; 96 had paroxysmal and 49 had chronic LAF. They were followed up with clinical and echocardiographic controls, and we recorded every thromboembolic complication and death. During the follow-up (10 +/- 8 years) among patients with paroxysmal LAF, 1 (1%) had an ischemic stroke, 2 a transient ischemic attack, and 1 a myocardial infarction. In the group with chronic LAF, 1 patient had moderate heart failure, 2 myocardial infarction, and 1 transient ischemic attack. In this group, 8 embolic complications in 7 (16.3%) patients were observed. One patient with intestinal embolism died during surgery; 2 (6.1%) patients died suddenly. CONCLUSIONS The prognosis of young patients with paroxysmal LAF appears to be excellent, whereas patients with chronic LAF are at increased risk of embolic complications and higher mortality rates. Our results suggest that LAF is not always a benign disorder, as suggested by previous studies. Subgroups with substantially increased risk for thromboembolic events caused by LAF should be better identified.

Clinical spectrum of fascicular tachycardia.

Aims Ventricular tachycardia spreading from the anterior or posterior division of the left bundle branch is generally called fascicular tachycardia (FT). We will present our experience with FT, a type of ventricular tachycardia not necessarily implying the absence of heart disease and/or sensitivity to selective antiarrhythmic drugs, but only particular routes of left ventricular depolarization. Methods Since 1981 we have had the opportunity to study 10 cases of FT (nine men and one woman; aged 28–77 years, mean ± SD 55 ± 18.6 years) by means of echocardiography, coronary angiography (seven cases), endomyocardial biopsy (five cases), signal-averaged electrocardiogram (SAECG, nine patients), electrophysiological and electropharmacological evaluation. Results Seven patients had paroxystic, extrastimulus inducible FT that was sensitive to verapamil given intravenously (group A); three patients, on the other hand, showed repetitive or incessant FT, not modifiable by stimulation techniques and sensitive to class 1 antiarrhythmic drugs (group B). Patients presented histologic substrates ranging from the absence of heart disease to previous myocardial infarction or myocarditis. FT spontaneously disappeared within 2 years in group B, while frequently persisted in the long term in group A. Conclusions FT is not a homogeneous group of ventricular tachycardia, as patients may differ according to clinical presentation, mechanisms that are involved in the genesis of the arrhythmia and natural history; the histologic substrate is highly variable, ranging from the total absence of heart disease to severe forms of myocardial involvement.