Frequent atrial premature beats predict paroxysmal atrial fibrillation in stroke patients: an opportunity for a new diagnostic strategy

BACKGROUND AND PURPOSE: For patients having suffered ischemic stroke, the current diagnostic strategies often fail to detect atrial fibrillation as a potential cause of embolic events. The aim of the study was to identify paroxysmal atrial fibrillation in stroke patients. We hypothesized that patients with frequent atrial premature beats (APBs) recorded in 24-hour ECG will show more often atrial fibrillation when followed by repeated long-term ECG recordings than patients without or infrequent APBs. METHODS: 127 patients with acute ischemic stroke and without known AF were enrolled in a prospective study to detect paroxysmal AF. Patients were stratified according to the number of APBs recorded in a 24-hour ECG (> or =70 APBs versus <70 APBs). Subsequently, they all underwent serial 7-day event-recorder monitoring at 0, 3, and 6 months. RESULTS: Serial extended ECG monitoring identified AF in 26% of patients with frequent APBs but only in 6.5% when APBs were infrequent (P=0.0021). A multivariate analysis showed that the presence of frequent APBs in the initial 24-hour ECG was the only independent predictor of paroxysmal AF during follow-up (odds ratio 6.6, 95% confidence intervals 1.6 to 28.2, P=0.01). CONCLUSIONS: In patients with acute ischemic stroke, frequent APBs (> or = 70/24 hours) are a marker for individuals who are at greater risk to develop or have paroxysmal AF. For such patients, we propose a diagnostic workup with repeated prolonged ECG monitoring to diagnose paroxysmal AF.

Activation of electrical triggers of atrial fibrillation in hyperthyroidism

A shortening of the atrial refractory period has been considered as the main mechanism for the increased risk of atrial fibrillation in hyperthyroidism. However, other important factors may be involved.

Atrial fibrillation following device closure of patent foramen ovale

OBJECTIVES: Recurrent embolic events after device closure of patent foramen ovale (PFO) have been related to incomplete closure. Another cause could be atrial fibrillation (AF). The aim of this study was to determine the incidence of AF in stroke patients after PFO closure. METHODS: Consecutive patients with device closure of a PFO after a stroke or transient ischemic attack and control patients with stroke underwent 7-day event loop recordings 3 and 6 months after PFO closure or stroke, respectively. RESULTS: Forty patients treated by PFO device closure 96 +/- 68 days after cryptogenic ischemic stroke and 70 control patients with ischemic stroke of other etiologies (known AF excluded) were compared. AF was identified in 6 patients (15%) of the treated group and in 12 control patients (17%, p = 0.77). In multivariate analysis, the presence of an occluder device was not an independent risk factor for AF. CONCLUSIONS: The incidence of AF is high after device closure of a PFO in stroke patients and similar to that in patients with stroke of non-PFO etiology and, hence, with no device. Further studies are required to determine the risk of thromboembolism and the optimal treatment in patients developing AF after device closure of a PFO.

Transseptal puncture for catheter ablation of atrial fibrillation after device closure of patent foramen ovale

The technique of transseptal puncture for catheter ablation of atrial fibrillation after percutaneous closure of a foramen ovale with the Amplatzer Occluder is demonstrated based on 2 representative cases.

Frequency of severe pulmonary hypertension complicating "isolated" atrial septal defect in infancy

Atrial septal defects (ASDs) are typically asymptomatic in infancy and early childhood, and elective defect closure is usually performed at ages of 4 to 6 years. Severe pulmonary hypertension (PH) complicating an ASD is seen in adulthood and has only occasionally been reported in small children. A retrospective study was undertaken to evaluate the incidence of severe PH complicating an isolated ASD and requiring early surgical correction. During a 10-year period (1996 to 2006), 355 pediatric patients underwent treatment for isolated ASDs either surgically or by catheter intervention at 2 tertiary referral centers. Two hundred ninety-seven patients had secundum ASDs, and 58 had primum ASDs with mild to moderate mitral regurgitation. Eight infants were found with isolated ASDs (6 with secundum ASDs and 2 with primum ASDs) associated with significant PH, accounting for 2.2% of all patients with ASDs at the centers. These 8 infants had invasively measured pulmonary artery pressures of 50% to 100% of systemic pressure. They were operated in the first year of life and had complicated postoperative courses requiring specific treatment for PH for up to 16 weeks postoperatively. The ultimate outcomes in all 8 infants were good, with persistent normalization of pulmonary pressures during midterm follow-up of up to 60 months (median 28). All other patients with ASDs had normal pulmonary pressures, and the mean age at defect closure was significantly older, at 6.2 years for secundum ASDs and 3.2 years for primum ASDs. In conclusion, ASDs were rarely associated with significant PH in infancy but then required early surgery and were associated with excellent midterm outcomes in these patients.

Gender differences in patients referred for atrial fibrillation management to a tertiary center

BACKGROUND: Atrial fibrillation (AF) ablation is less frequently performed in women than in men. Although the prevalence of AF is slightly higher in men, this does not fully account for the lower number of AF ablations performed in women. This study sought to examine the effect of gender on referral for AF and subsequent AF management. METHODS: Consecutive patients referred to our tertiary arrhythmia outpatient clinic for AF management were retrospectively analyzed. RESULTS: Of 264 patients referred, only 27% were women. Women were older than men (63 +/- 9 vs 58 +/- 11 years, P = 0.002), more often had paroxysmal AF (78% vs 63% in men, P = 0.022), and women more frequently complained about palpitations (71% vs 49%, P = 0.002). In addition, they had more often experienced amiodarone side effects than men (56% vs 36%, P = 0.046). In this referred population, there was no difference in the proportion of women and men undergoing AF ablation immediately following the initial evaluation (21% vs 25%, P = ns), at any time during the follow-up (38% vs 44%, P = ns), and there was no difference in the proportion of patients undergoing atrioventricular node ablation in both sexes (6% of women vs 3% of men, P = ns). CONCLUSIONS: There is an important difference in the proportion of men and women referred for management of AF in a specialized outpatient arrhythmia clinic, with women being referred three times less often than men. However, there is no gender-related difference in the subsequent treatment decisions. These findings emphasize the importance of focusing on management of symptomatic AF in women.

Myocardial infarction due to paradoxical embolism in a patient with large atrial septal defect

We present the case of a patient who presented with acute inferior myocardial infarction and embolic occlusion of the distal left anterior descending and proximal right coronary artery. A large atrial septal defect (ASD) was seen on transesophageal echocardiography and the ASD was closed during the same session as coronary angiography and percutaneous coronary intervention. The presence of embolic or thrombotic occlusions of coronary arteries should prompt interventional cardiologists to look for a patent foramen ovale or ASD and perform percutaneous closure right away.