Enhanced detection of patent foramen ovale by systematic transthoracic saline contrast echocardiography

Objective

We aimed to evaluate the effectiveness of transthoracic saline contrast echocardiography (TSCE) in detecting patent foramen ovale (PFO).

Background

Transesophageal echocardiography (TEE) is semi-invasive and not ideal for PFO screening.

Methods

112 patients (48 males, 46 ± 14 years) with suspected PFO received intravenous agitated-saline contrast at rest and stress (strain and release phases of Valsalva maneuver and coughing). The presence of interatrial shunting was defined as > 5 bubbles appearing in the left heart within 3 cardiac cycles. The stage of the maneuver at which interatrial shunting occurred was recorded. The TSCE findings were validated by TEE.

Results

TEE identified PFO in 45% of patients. The sensitivities of TSCE in detecting PFO at rest, during strain and release of Valsalva maneuver, and coughing were 12.0%, 38.0%, 80.0% and 94.0% respectively (each p < 0.05 when compared to previous stage). Specificities were similar and > 95% for all stages. Moreover, the release phase of the maneuver improved the diagnostic accuracy [defined as (number of true positives + true negatives) divided by total in sample] with incremental value over the preceding strain phase (89.2 vs. 70.5%, p < 0.001).

Conclusions

Patent foramen ovale can be identified confidently with proper conduct of the Valsalva maneuver during the transthoracic saline contrast echocardiography.     

Atrial stunning: determinants and cellular mechanisms

Background

Atrial stunning is a transient depression of atrial and atrial-appendage mechanical function after successful cardioversion of atrial fibrillation compared with its precardioversion state.

Method

Atrial stunning associated with different methods of cardioversion of atrial fibrillation and the determinants and cellular mechanisms of atrial stunning were elaborated by thoroughly examining the studies on the subject identified through a comprehensive literature search.

Results and conclusion

Atrial stunning has been reported with all methods of cardioversion of atrial fibrillation, including transthoracic electrical, low-energy internal electrical, pharmacological, and spontaneous. It is a function of the underlying atrial fibrillation becoming apparent at the restoration of sinus rhythm, regardless of the method used for conversion. Unsuccessful cardioversion does not result in atrial stunning. The duration of the preceding atrial fibrillation, atrial size, and underlying structural heart disease are the determinants of atrial stunning. A shorter duration of atrial fibrillation and smaller atrial diameters are associated with a relatively less severe stunning, lasting for a shorter duration. Atrial stunning after cardioversion of atrial fibrillation of <1 week usually resolves within 24 hours, and atrial stunning after cardioversion of chronic atrial fibrillation usually resolves within 4 weeks. Tachycardia-induced atrial cardiomyopathy, atrial cytosolic calcium alterations with down-regulation of the L-type Ca2+ channels and up-regulation of the Na+/Ca2+ exchanger, atrial hibernation with myocyte dedifferentiation and myolysis, and atrial fibrosis are the suggested mechanisms underlying atrial stunning. Atrial stunning determines the risk of postcardioversion thrombus formation in atria and atrial appendages, the duration of postcardioversion anticoagulation therapy, the recovery of the atrial contribution to the ventricular function, and the functional recovery of the patients after successful cardioversion of atrial fibrillation.     

Racial Differences in Atrial Fibrillation Prevalence and Left Atrial Size

Background

Previous studies relying on clinical care data have suggested that atrial fibrillation is less common in African Americans than Caucasians, but the mechanism remains unknown. Clinical care may itself vary by race, potentially affecting the accuracy of atrial fibrillation ascertainment in studies relying on clinical data. We sought to examine racial differences in atrial fibrillation prevalence determined by protocol-driven electrocardiograms (ECGs) obtained in prospective cohort studies and to study racial differences in echocardiographic characteristics.

Methods

We pooled primary data from 3 cohort studies with atrial fibrillation adjudicated from study protocol ECGs and documentation of potentially important confounders: the Heart and Soul Study (n = 1014), the Heart and Estrogen-Progestin Replacement Study (n = 2673), and The Osteoporotic Fractures in Men Sleep Study (n = 2911). Left atrial anatomic dimensions were compared among races from sinus rhythm echocardiograms in the Heart and Soul Study.

Results

Of the 6611 participants, 268 (4%) had atrial fibrillation: Caucasians had the highest prevalence (5%), and African Americans had the lowest (1%; P <.001 for each compared with all other races). After adjustment for potential confounders, Caucasians had a 3.8-fold greater odds of having atrial fibrillation than African Americans (95% confidence interval, 1.6-8.8, P = .002). Although ventricular and atrial volumes and function were similar in Caucasians and African Americans, Caucasians had a 2 mm larger anterior-posterior left atrial diameter after adjusting for potential confounders (95% confidence interval, 1-3 mm, P <.001).

Conclusion

ECG confirmed atrial fibrillation is more common in Caucasians than in African Americans, which might be related to the larger left atrial diameter observed in Caucasians.     

Patent Foramen Ovale and Migraine Attacks: A Systematic Review

Background

Migraine headache and the presence of a patent foramen ovale have been associated with each other, although the precise pathophysiological mechanism(s) are uncertain. The purpose of this systematic review was to identify the extent of patent foramen ovale prevalence in migraineurs and to determine whether closure of a patent foramen ovale would improve migraine headache.

Methods

An electronic literature search was performed to select studies between January 1980 and February 2013 that were relevant to the prevalence of patent foramen ovale and migraine, and the effects of intervention(s) on migraine attacks. Of the initial 368 articles presented by the initial search, 20 satisfied the inclusion criteria assessing patent foramen ovale prevalence in migraineurs and 21 presented data on patent foramen ovale closure.

Results

In case series and cohort studies, patent foramen ovale prevalence in migraineurs ranged from 14.6% to 66.5%. Case-control studies reported a prevalence ranging from 16.0% to 25.7% in controls, compared with 26.8% to 96.0% for migraine with aura. The extent of improvement or resolution of migraine headache attack symptoms was variable. In case series, intervention ameliorated migraine headache attack in 13.6% to 92.3% of cases. One single randomized trial did not show any benefit from patent foramen ovale closure. The data overall do not exclude the possibility of a placebo effect for resolving migraine following patent foramen ovale closure.

Conclusion

This systematic review demonstrates firstly that migraine headache attack is associated with a higher prevalence of patent foramen ovale than among the general population. Observational data suggest that some improvement of migraine would be observed if the patent foramen ovale were to be closed. A proper assessment of any interventions for patent foramen ovale closure would require further large randomized trials to be conducted given uncertainties from existing trial data.     

Do baseline atrial electrocardiographic and infarction patterns predict new-onset atrial fibrillation after ST-elevation myocardial infarction? Insights from the Assessment of Pexelizumab in Acute Myocardial Infarction Trial

Background

Atrial infarction reportedly occurs in 0.7% to 52% of ST-elevation myocardial infarctions (STEMIs), up to two thirds of whom develop atrial fibrillation and flutter (AF). Prospective validation of electrocardiographic atrial infarction patterns is lacking. Hence, in STEMI patients treated with primary percutaneous coronary intervention, we examined whether baseline atrial electrocardiographic changes or atrial infarction patterns predicted new AF or mortality.

Methods

Within the Assessment of Pexelizumab in Acute Myocardial Infarction trial, a nested case-control study was conducted. Patients with new AF were matched 1:1 with controls, and baseline atrial electrocardiographic variables were examined.

Results

Abnormal P wave morphology (Liu minor criterion for atrial infarction) was significantly associated with new AF (adjusted odds ratio, 1.68; 1.03-2.73). This was also independently associated with 90-day mortality in the overall case-control cohort (adjusted hazard rate, 1.90; 1.04-3.46) and among patient with new-onset AF (adjusted hazard rate, 2.43; 1.22-4.84).

Conclusions

Abnormal P wave morphology significantly predicted new AF and 90-day mortality in STEMI patients.     

Outcome of direct current cardioversion for atrial arrhythmias in adults with congenital heart disease

Objectives

We sought to evaluate safety, efficacy, and outcome of direct current cardioversion (DCCV) for atrial arrhythmias in adults with congenital heart disease (CHD).

Background

Atrial arrhythmias are increasingly noted in adults with CHD. The outcome of DCCV for atrial arrhythmias in this population is unknown.

Methods

Our study was a retrospective review of patients 18 years or older with CHD who underwent DCCV between June 2000 and July 2003. This constituted the CHD group. Patient characteristics reviewed included the specific cardiac diagnosis and arrhythmia history. A subset of patients had transesophageal echocardiography (TEE) before DCCV; this subset was reviewed to evaluate spontaneous echocardiographic contrast. The outcome data evaluated included success of DCCV, complications, recurrence of arrhythmia, antiarrhythmic medication use, electrophysiology or pacemaker procedure in follow-up, and all-cause mortality. The recurrence rate of the arrhythmia was compared to a control group consisting of an age, gender, and rhythm matched group of patients who have no CHD and who underwent DCCV for atrial arrhythmias.

Results

Sixty-three patients in the CHD group underwent 80 DCCVs, 59 of which were TEE-guided. Atrial flutter was more common in the CHD group (37 of 80 DCCV, 46%) than in the control group (13 of 56, 23%) (p < 0.001). DCCV was successful in 75 (94%). Mean follow-up was 387 days. No thromboembolic events were noted. All-cause mortality on follow-up was 11%. There was no death related to DCCV. Twenty-five patients in the CHD group (40%) remained in sinus rhythm throughout follow-up. This was similar to that observed in the control group (30/56, 54%, p = 0.13). Recurrent arrhythmia in the CHD group was predicted by the presence of atrial fibrillation (p = 0.009) and less so spontaneous echo contrast in the left atrium (p = 0.05).

Conclusions

DCCV with appropriate anticoagulation is safe and effective for patients with CHD, even in the presence of an intracardiac shunt and spontaneous contrast on TEE. However, the recurrence rate is substantial. Spontaneous echo contrast in the left atrium along with atrial fibrillation predicts arrhythmia recurrence following DCCV in patients with CHD.     

Circadian variation of arrhythmia onset patterns in patients with persistent atrial fibrillation

Background

The circadian onset patterns and cycle lengths of atrial tachyarrhythmias (AT) were determined in a group of patients with persistent atrial fibrillation.

Methods

Fifteen patients, mean age 63 ± 14 years and 80% male, were implanted with the Jewel AF atrial defibrillator (Medtronic, Minneapolis, Minn) for persistent atrial fibrillation only. Onset times of AT and median onset atrial cycle lengths were determined from device memory.

Results

Over a follow-up period of 23.3 ± 7 months, 227 episodes of persistent AT were treated by patient-activated atrial defibrillation. The peak onset of persistent AT was nocturnal, with 74% of episodes initiating between 8 pm and 8 am. Eighty-seven percent of the patients experienced an additional 403 paroxysmal AT episodes. These episodes showed a “double-peaked” pattern with the least number of episodes occurring between midnight and 8 am. The mean onset atrial cycle length of persistent AT was significantly shorter than the paroxysmal AT episodes (200 ± 37 ms vs 240 ± 39 ms, P < .005). The atrial cycle lengths at arrhythmia onset of both paroxysmal and persistent AT episodes also demonstrated circadian variation.

Conclusion

There is a circadian distribution of onsets for persistent AT with predominance at night. Patients with persistent AF have >1 type of atrial arrhythmia with differences in the onset patterns and atrial cycle lengths, suggesting different triggers and onset mechanisms.     

Diagnosis and quantification of patent foramen ovale. Which is the reference technique? Simultaneous study with transcranial Doppler, transthoracic and transesophageal echocardiography

Introduction and objectives

Patent foramen ovale (PFO) is the most common cause of cryptogenic stroke in patients younger than 55. Transesophageal echocardiography (TEE) has been accepted as the reference diagnostic technique. The purpose of this study was to compare the accuracy of transthoracic echocardiography (TTE), TEE and transcranial Doppler (TCD) in the diagnosis and quantification of patent foramen ovale.

Methods

We studied 134 patients prospectively. Simultaneous TTE with TCD and TEE with TCD were performed, using agitated saline solution to detect right to left shunt.

Results

In 93 patients diagnosed with PFO, the shunt was visualized at baseline by TCD in 69% of cases, by TTE in 74% and by TEE in 58%. The Valsalva maneuver produced a similar improvement in shunt diagnosis with all 3 techniques (26%-28%). TTE and TCD showed higher sensitivity (100% vs 97%; non significant difference) than TEE in the diagnosis of PFO (86%; P < .001). TCD performed during TEE did not diagnose 12 (13%) shunts previously diagnosed during TTE. Similarly, TEE underestimated shunt severity.

Conclusions

TTE enables adequate diagnosis and quantification of PFO. TEE is less sensitive and tends to underestimate the severity of the shunt.Full English text available from: www.revespcardiol.org     

Enalapril treatment and hospitalization with atrial tachyarrhythmias in patients with left ventricular dysfunction

Background

Experimental and clinical evidence suggests a preventive role for agiotensin-coverting enzyme (ACE) inhibitors on the development of atrial fibrillation. However, the effect of ACE inhibition on hospitalization with atrial tachyarrhythmias in patients with left ventricular (LV) dysfunction is not known. We sought to determine whether enalapril treatment reduced hospitalizations with atrial tachyarrhythmias in patients with LV dysfunction.

Methods

We performed a retrospective analysis of the Studies of Left Ventricular Dysfunction (SOLVD) trial. Hospitalizations with atrial tachyarrhythmias were noted.

Results

A total of 192 hospitalizations with atrial tachyarrhythmias occurred in 158 patients during a follow-up period of 34 months. The time to first hospitalization with atrial tachyarrhythmias or death was significantly lower in the enalapril group (P = .005). In a multivariate analysis adjusting for the presence of atrial fibrillation at study entry, enalapril treatment was associated with a reduction in the rate of hospitalization with atrial tachyarrhythmias or death (RR, 0.87; 95% CI, 0.79-0.96; P = .007). The incidence of hospitalization with atrial tachyarrhythmias was 7.9 hospitalizations per 1000 patient-years of follow-up in the enalapril group, compared with 12.4 per 1000 patient-years in the placebo group (RR, 0.64; 95% CI, 0.48-0.85; P = .002).

Conclusion

Enalapril is associated with a decreased incidence of hospitalization with atrial tachyarrhythmias in patients with LV dysfunction.     

C825T polymorphism of the G-protein beta3 subunit gene and atrial fibrillation: association of the TT genotype with a reduced risk for atrial fibrillation

Background

A polymorphism consisting of a C825T substitution in the G-protein β₃ subunit gene (GNB3) has been associated with enhanced human atrial inward rectifier potassium currents regarding the TT genotype. Therefore, we investigated a possible impact of the GNB3 C825T polymorphism on atrial fibrillation in an association study.

Methods

Two hundred ninety-one consecutive patients admitted to our center with atrial fibrillation (age, 58 ± 10 years) and 292 consecutive control patients without atrial tachyarrhythmias (59 ± 11 years) were genotyped for the C825T polymorphism. Patients with coronary heart disease, valvular heart disease, or cardiomyopathy were excluded from the study. Both patient groups had a similar incidence of cardiovascular risk factors (hypertension, hypercholesterolemia, body mass index).

Results

The prevalence of the GNB3 TT genotype was significantly lower in patients with atrial fibrillation (5.8%) than in the control group (12.0%); however, no significant differences in the frequencies of the CT and CC genotypes were found. The TT genotype was associated with a 54% decrease in the adjusted risk (OR from a multivariant model, 0.46; 95% CI, 0.24 to 0.87; P = .02) for the occurrence of atrial fibrillation.

Conclusions

The current study suggests an association between the GNB3 TT genotype and a reduced risk for the occurrence of atrial fibrillation.     

Five-year clinical and echocardiographic evaluation of the Das AngelWings atrial septal occluder

Background

The late outcome of patients treated with atrial septal occluder devices remains incompletely defined. The purpose of this study was to assess the late outcome (range 4-7 years postprocedure) of patients in whom the Das AngelWings septal occluder device was implanted in the atrial septum. We report the clinical and echocardiographic outcome, at an average of 5 years following the procedure, of patients treated with the Das AngelWings device used to close either a secundum atrial septal defect (ASD) or a patent foramen ovale (PFO).

Methods

Thirty-two patients underwent successful percutaneous closure of an atrial septal closure, patent foramen ovale, or fenestration in the lateral tunnel of their Fontan with the Das AngelWings device between June 1995 and March 1998 at Duke University Medical Center. Two of the 32 patients were lost to follow-up. The remaining 30 patients were divided into 3 groups based on indication for device implantation. Group 1 consisted of 14 patients with a secundum ASD and predominantly left-to-right atrial shunting. Group 2 consisted of 8 patients who had a PFO and who suffered a thromboembolic event. Group 3 (compassionate use) consisted of 10 patients with multiple comorbid medical problems with predominantly right-to-left shunting at the atrial level causing hypoxemia. Eight of the patients in group 3 were severely ill at the time of device implantation. The 2 remaining patients in group 3 underwent AngelWings implantation for closure of right-to-left shunting through a Fontan fenestration. Mean follow-up was 59 months.

Results

There was no device embolization. No patient in the ASD or PFO/stroke group had a clinical complication. By radiographic examination, 2 of 27 patients had evidence of fracture of the nitinol framework at 2-year follow-up. Residual shunting was present in 44% at 24 hours, 20% at 1 year, and 18.8% at 2 years by use of Doppler color flow imaging and/or microcavitation echocardiographic studies. Mild mitral regurgitation caused by the AngelWings device occurred in 1 patient.One patient in the compassionate use group had a subsequent neurologic event. Five of the 10 patients in the compassionate use group died of comorbid illnesses in follow-up, none directly related to device complications.

Conclusion

The late clinical outcome of secundum ASD and PFO/stroke patients in this study demonstrates that Das AngelWings closure of the atrial septum is effective and safe. These data are encouraging with respect to the expanding use of other percutaneously implanted ASD occlusion devices, although late clinical safety and efficacy data are needed for the specific devices being implanted.     

Expression of spliceosome assembly factor SC-35 in TUNEL-positive atrial cardiomyocytes in mitral and tricuspid regurgitation: Viability of atrial cardiomyocytes

Background

Most of the atrial cardiomyocytes with positive terminal deoxynucleotidyl transferase (TdT)-mediated dUTP in situ nick end-labelling (TUNEL) reaction are not apoptotic in patients with mitral and tricuspid valve diseases. The TUNEL-positive myocytes with expression of spliceosome assembly factor SC-35, an indicator of increased RNA synthesis, should be living cardiomyocytes.

Methods

This study analyzed twenty-three patients with significant mitral and tricuspid regurgitation. Fifteen patients had persistent atrial fibrillation, and eight had sinus rhythm. Atrial appendageal tissues were obtained during surgery. Immunohistochemical study was performed.

Results

Immunohistochemical study of fibrillating right atrial myocardium demonstrated that 44.8 ± 24.6% of myocytes had TUNEL-positive nuclei whereas 39.4 ± 21.4% of myocytes had TUNEL-positive nuclei in sinus right atrial myocardium (p = 0.682). However, most (81.6%) nuclei of TUNEL-positive myocytes in the fibrillating right atria also expressed proliferating cell nuclear antigen (PCNA), an indicator of DNA replication and repair, and most nuclei (91.8%) of TUNEL-positive myocytes also expressed SC-35. In fibrillating left atria, most (88.1%) nuclei of TUNEL-positive myocytes also expressed SC-35. Similarly, in sinus right atrial myocardium, most (78.0%) nuclei of TUNEL-positive myocytes expressed PCNA, and most (91.4%) nuclei of TUNEL-positive myocytes also expressed SC-35, but none expressed Ki-67, a replication-associated antigen. Additionally, the percentage of TUNEL-positive myocytes in the right atria significantly and positively correlated with the percentage of PCNA-positive myocytes (r = 0.826, p < 0.001) and SC-35 positive myocytes (r = 0.713, p < 0.001).

Conclusions

Most TUNEL-positive atrial cardiomyocytes in patients with mitral and tricuspid regurgitation are living cardiomyocytes.     

Influence of Obesity on Outcomes in Atrial Fibrillation: Yet Another Obesity Paradox

Background

Obese patients have favorable outcomes in congestive heart failure, hypertension, peripheral vascular disease, and coronary artery disease. Obesity also has been linked with increased incidence of atrial fibrillation, but its influence on outcomes in atrial fibrillation patients has not been investigated. The objective of this research is to investigate the effect of obesity on outcomes in atrial fibrillation.

Methods

The Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study was one of the largest multicenter trials of atrial fibrillation, with 4060 patients. Subjects were randomized to rate versus rhythm-control strategy. We performed a post hoc analysis of the National Heart, Lung and Blood Institute limited access dataset of atrial fibrillation patients who had body mass index (BMI) data available in the AFFIRM study. BMI data were not available on 1542 patients. Patients with BMI ≥18.5 were split into normal (18.5-25), overweight (25-30), and obese (>30) categories as per BMI (kg/m²). Multivariate Cox proportional hazards regression was used on the eligible 2492 patients. End points were all-cause mortality and cardiovascular mortality.

Results

Over three fourths of all patients in our cohort were overweight or obese. There were 304 deaths (103 among normal weight, 108 among overweight, and 93 among obese) and 148 cardiovascular deaths (54 among normal weight, 41 among overweight, and 53 among obese) over a mean period of 3 years of patient follow-up. On multivariate analysis, overweight (hazard ratio [HR] 0.64; 95% confidence interval [CI], 0.48-0.84; P = .001) and obese (HR 0.80; 95% CI, 0.68-0.93; P = .005) categories were associated with lower all-cause mortality as compared with normal weight. Overweight (HR 0.40; 95% CI, 0.26-0.60; P <.001) and obese patients (HR 0.77; 95% CI, 0.62-0.95; P = .01) also had lower cardiovascular mortality as compared with the normal weight patients.

Conclusions

Although in prior studies, obesity has been associated with increased risk of atrial fibrillation, an obesity paradox exists for outcomes in atrial fibrillation. Obese patients with atrial fibrillation appear to have better long-term outcomes than nonobese patients.     

Warfarin Use and Outcomes in Patients with Atrial Fibrillation Complicating Acute Coronary Syndromes

Background

We examined warfarin use at discharge (according to Congestive heart failure, Hypertension, Age > 75 years, Diabetes, Prior Stroke/transient ischemic attack score and bleeding risk) and its association with 6-month death or myocardial infarction in patients with post-acute coronary syndrome atrial fibrillation.

Methods

Of the 23,208 patients enrolled in the Platelet IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy, Platelet IIb/IIIa Antagonist for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network A, and Superior Yield of the New Strategy of Enoxaparin, Revascularization and Glycoprotein IIb/IIIa Inhibitors trials, 4.0% (917 patients) had atrial fibrillation as an in-hospital complication and were discharged alive. Cox proportional hazards models were performed to assess 6-month outcomes after discharge.

Results

Overall, 13.5% of patients with an acute coronary syndrome complicated by atrial fibrillation received warfarin at discharge. Warfarin use among patients with atrial fibrillation had no relation with estimated stroke risk; similar rates were observed across Congestive heart failure, Hypertension, Age > 75 years, Diabetes, Prior Stroke/transient ischemic attack (CHADS₂) scores (0, 13%; 1, 14%; ≥ 2, 13%) and across different bleeding risk categories (low risk, 11.9%; intermediate risk, 13.3%; high risk, 11.1%). Among patients with in-hospital atrial fibrillation, warfarin use at discharge was independently associated with a lower risk of death or myocardial infarction within 6 months of discharge (hazard ratio 0.39; 95% confidence interval, 0.15-0.98).

Conclusion

Warfarin is associated with better 6-month outcomes among patients with atrial fibrillation complicating an acute coronary syndrome, but its use is not related to CHADS₂ score or bleeding risk.     

Low prevalence of atrial fibrillation in community-dwelling Chinese aged 55 years or older in Singapore: a population-based study

Background

The prevalence of atrial fibrillation (AF) in Asian populations appears to be lower than that in Western populations according to limited data. We conducted a community study to (a) estimate the prevalence of AF in Chinese adults aged 55 years or older in Singapore and (b) examine associated risk factors.

Methods

We conducted a whole-survey area population screening of 1839 Chinese residents aged 55 years or older in the southeast region of Singapore with a single electrocardiographic recording. We performed structured interviews and anthropometric as well as clinical measurements, including blood pressure.

Results

The estimated overall AF prevalence was 1.5% (95% confidence interval = 1.1-2.2); specifically, the prevalence was higher in men (2.6%) than in women (0.6%) and increased sharply to 5.8% only in individuals aged 80 years or older. This latter rate is lower than age-standardized rates in Western populations by approximately half and consistent with similarly low prevalence rates reported for Korea and China. Of the 26 cases of AF in this study, only 10 were known cases; 3 of the 10 patients were receiving anticoagulant therapy, whereas the rest were receiving antiplatelet therapy. Atrial fibrillation was significantly associated in multivariate analyses with male sex (odds ratio [OR] = 4.10), heart failure (OR = 3.11), and stroke (OR = 3.60).

Conclusions

These data add support to the view that the prevalence of AF in Asian populations is lower than that in Western populations. The observations from these contrasting populations warrant attention in future studies.     

Migraine headaches following catheter ablation for atrial fibrillation

Background  

Atrial septal defects (ASD), including patent foramen ovale, have been linked to an increased prevalence of migraine headaches in the general population. A similar association with migraine is speculated for iatrogenic ASD due to atrial septal puncture during catheter ablation for atrial fibrillation (AF).     

Influence of coffee and caffeine consumption on atrial fibrillation in hypertensive patients

Background and aims

Coffee and caffeine are widely consumed in Western countries. Little information is available on the influence of coffee and caffeine consumption on atrial fibrillation (AF) in hypertensive patients. We sought to investigate the relationship between coffee consumption and atrial fibrillation with regard to spontaneous conversion of arrhythmia.

Methods and results

A group of 600 patients presenting with a first known episode of AF was investigated, and we identified 247 hypertensive patients. The prevalence of nutritional parameters was assessed with a food frequency questionnaire. Coffee and caffeine intake were specifically estimated. Left ventricular hypertrophy was evaluated by electrocardiogram (ECG) and echocardiogram. Coffee consumption was higher in normotensive patients. High coffee consumers were more frequent in normotensive patients compared with hypertensive patients. On the other hand, the intake of caffeine was similar in hypertensive and normotensive patients, owing to a higher intake in hypertensive patients from sources other than coffee. Within normotensive patients, we report that non-habitual and low coffee consumers showed the highest probability of spontaneous conversion (OR 1.93 95%CI 0.88-3.23; p = 0.001), whereas, within hypertensive patients, moderate but not high coffee consumers had the lowest probability of spontaneous conversion (OR 1.13 95%CI 0.67-1.99; p = 0.05).

Conclusion

Coffee and caffeine consumption influence spontaneous conversion of atrial fibrillation. Normotensive non-habitual coffee consumers are more likely to convert arrhythmia within 48 h from the onset of symptoms. Hypertensive patients showed a U-shaped relationship between coffee consumption and spontaneous conversion of AF, moderate coffee consumers were less likely to show spontaneous conversion of arrhythmia. Patients with left ventricular hypertrophy showed a reduced rate of spontaneous conversion of arrhythmia.     

Alterations of atrial electrophysiology related to hemodialysis session: insights from a multiscale computer model

Background

The prevalence of atrial fibrillation is increased in patients with end-stage renal disease. Previous studies suggested that extracellular electrolyte alterations caused by hemodialysis (HD) therapy could be proarrhythmic.

Methods

Multiscale models were used for a consequent analysis of the effects of extracellular ion concentration changes on atrial electrophysiology. Simulations were based on measured electrolyte concentrations from patients with end-stage renal disease.

Results

Simulated conduction velocity and effective refractory period are decreased at the end of an HD session, with potassium having the strongest influence. P-wave is prolonged in patients undergoing HD therapy in the simulation as in measurements.

Conclusions

Electrolyte concentration alterations impact atrial electrophysiology from the action potential level to the P-wave and can be proarrhythmic, especially because of induced hypokalemia. Analysis of blood electrolytes enables patient-specific electrophysiology modeling. We are providing a tool to investigate atrial arrhythmias associated with HD therapy, which, in the future, can be used to prevent such complications.     

Elevated NT-proBNP levels should be interpreted in elderly patients presenting with dyspnea

Background

B-type natriuretic peptide (BNP) assay is a useful tool in order to diagnose dyspnea due to congestive heart failure (CHF). On the other hand many other diseases could affect BNP levels. The aim of this study was to investigate a group of elderly patients admitted to an Internal Medicine unit because of dyspnea.

Patients and methods

NT-proBNP was assessed in 132 consecutive patients aged 80 ± 6 years because of dyspnea. History data, anthropometric, clinical and biochemical parameters were collected. Renal function was assessed by the CKD-EPI formula. Diagnosis of pulmonary disease such as infections and chronic obstructive disease was considered and was analyzed as a single parameter. Statistical analysis was carried out dividing patients with high NT-proBNP from those with normal NT-proBNP according to the Januzzi cut-off.

Results

NT-proBNP was higher than the normal reference values in 68.7% of patients and its levels increased in the 5 different stages of chronic kidney disease. Subjects with high NT-proBNP had lower haemoglobin levels (11.6 ± 2.1 vs 12.8 ± 1.9 g/dl, p = 0.003), higher prevalence of atrial fibrillation (54.3 vs 25%, p = 0.001), and lower prevalence of pulmonary diseases (29.7 vs 57.5%, p = 0.005). Logistic regression analysis showed that NT-proBNP levels were independently associated with haemoglobin (OR 1.307 95% CI 1.072-1.593, p = 0.008) and pulmonary diseases (OR 3.069 95% CI 1.385-6.801, p = 0.006).

Conclusions

A disease different from CHF appears to affect NT-proBNP plasma levels. Therefore, determination of its levels does not seem to help clinicians in the definition of dyspnea in elderly people with different comorbidities.     

Patent Foramen Ovale Closure for Secondary Prevention of Cryptogenic Stroke: Updated Meta-Analysis of Randomized Clinical Trials

Background

Patent foramen ovale closure represents a potential secondary prevention strategy for cryptogenic stroke, but available trials have varied by size, device studied, and follow-up.