Long-term Prognosis of Paroxysmal Atrial Fibrillation and Predictors for Progression to Persistnt or Chronic Atrial Fibrillation in the Korean Population.

Little is known about the long-term prognosis of or predictors for the different clinical types of atrial fibrillation (AF) in Korean populations. The aim of this study was to validate a risk stratification to assess the probability of AF progression from paroxysmal AF (PAF) to persistent AF (PeAF) or permanent AF. A total of 434 patients with PAF were consecutively enrolled (mean age; 71.7 ± 10.7 yr, 60.6% male). PeAF was defined as episodes that are sustained > 7 days and not self-terminating, while permanent AF was defined as an ongoing long-term episode. Atrial arrhythmia during follow-up was defined as atrial premature complex, atrial tachycardia, and atrial flutter. During a mean follow-up of 72.7 ± 58.3 months, 168 patients (38.7%) with PAF progressed to PeAF or permanent AF. The mean annual AF progression was 10.7% per year. In univariate analysis, age at diagnosis, body mass index, atrial arrhythmia during follow-up, left ventricular ejection fraction, concentric left ventricular hypertrophy, left atrial diameter (LAD), and severe mitral regurgitation (MR) were significantly associated with AF progression. In multivariate analysis, age at diagnosis (P = 0.009), atrial arrhythmia during follow-up (P = 0.015), LAD (P = 0.002) and MR grade (P = 0.026) were independent risk factors for AF progression. Patients with younger age at diagnosis, atrial arrhythmia during follow-up, larger left atrial chamber size, and severe MR grade are more likely to progress to PeAF or permanent AF, suggesting more intensive medical therapy with close clinical follow-up would be required in those patients.

Left-to-right atrial inward rectifier potassium current gradients in patients with paroxysmal versus chronic atrial fibrillation.

BACKGROUND: Recent evidence suggests that atrial fibrillation (AF) is maintained by high-frequency reentrant sources with a left-to-right-dominant frequency gradient, particularly in patients with paroxysmal AF (pAF). Unequal left-to-right distribution of inward rectifier K(+) currents has been suggested to underlie this dominant frequency gradient, but this hypothesis has never been tested in humans. METHODS AND RESULTS: Currents were measured with whole-cell voltage-clamp in cardiomyocytes from right atrial (RA) and left (LA) atrial appendages of patients in sinus rhythm (SR) and patients with AF undergoing cardiac surgery. Western blot was used to quantify protein expression of I(K1) (Kir2.1 and Kir2.3) and I(K,ACh) (Kir3.1 and Kir3.4) subunits. Basal current was ≈2-fold larger in chronic AF (cAF) versus SR patients, without RA-LA differences. In pAF, basal current was ≈2-fold larger in LA versus RA, indicating a left-to-right atrial gradient. In both atria, Kir2.1 expression was ≈2-fold greater in cAF but comparable in pAF versus SR. Kir2.3 levels were unchanged in cAF and RA-pAF but showed a 51% decrease in LA-pAF. In SR, carbachol-activated (2 µmol/L) I(K,ACh) was 70% larger in RA versus LA. This right-to-left atrial gradient was decreased in pAF and cAF caused by reduced I(K,ACh) in RA only. Similarly, in SR, Kir3.1 and Kir3.4 proteins were greater in RA versus LA and decreased in RA of pAF and cAF. Kir3.1 and Kir3.4 expression was unchanged in LA of pAF and cAF. CONCLUSION: Our results support the hypothesis that a left-to-right gradient in inward rectifier background current contributes to high-frequency sources in LA that maintain pAF. These findings have potentially important implications for development of atrial-selective therapeutic approaches.

Natriuretic peptides and right atrial fibrosis in patients with paroxysmal versus persistent atrial fibrillation.

Natriuretic peptides (NPs) are excellent diagnostic and prognostic markers of heart failure, but their roles in atrial fibrillation (AF), particularly of isolated cardiac valvular origin, are unclear. We assessed the mRNA and protein content of pro-atrial natriuretic peptide (pro-ANP) and pro-brain natriuretic peptide (pro-BNP) in right atrial appendages (RAAs) and their N-terminal fragments (nt-proANP and nt-proBNP) in the plasma of 30 patients with paroxysmal AF (PaAF) and 40 patients with persistent AF (PeAF) matched with 34 patients in sinus rhythm (SR) undergoing isolated valvular replacement. To explore the underlying mechanism, fibrosis related examinations were simultaneously carried out in RAAs. Unexpectedly, atrial expression of pro-NPs mRNA was notably augmented in the PaAF subgroup, but not so pronounced in the PeAF subgroup. Atrial content of pro-NPs proteins and plasma nt-proNPs, between which surprisingly strong positive correlations were found (pro-ANP and nt-proANP: r=0.918, p<0.001; pro-BNP and nt-proBNP: r=0.913, p<0.001), were increased analogously in PaAF and PeAF subgroups. We identified significantly increasing gradients of atrial collagen volume fraction (CVF), levels of collagen I and III in the SR, PaAF and PeAF groups, and convincing negative linear correlations between CVF, levels of collagen I and III, and atrial transcripts of pro-NPs. These findings suggest that the discordance between transcripts and protein contents of pro-NPs was possibly due to the more outstanding atrial fibrosis in PeAF, and that circulating nt-proNPs levels could reflect the corresponding atrial pro-NPs contents in this report.

Concealed left superior accessory pathway. Distinctive features of retrograde atrial activation and successful ablation using transseptal approach.

Concealed left superior accessory pathways are very infrequent and can be difficult to diagnose and ablate. We describe here the case of a patient presenting with reciprocating tachycardia involving superior and inferior left accessory pathways. Left superior accessory pathway was suspected because of the simultaneous retrograde atrial activation at the distal coronary sinus (CS) and His bundle lead and could be successfully ablated using transseptal catheterization.

Successful radiofrequency ablation of a right posteroseptal accessory pathway through an anomalous inferior vena cava and azygos continuation in a patient with incomplete situs inversus.

We present a 43-year-old patient with paroxysmal supraventricular tachycardia. In the process of catheter ablation, we found interruption of the inferior vena cava with azygos continuation with incomplete situs inversus. In this patient, we adopted the lower approach via the anomalous inferior vena cava and azygos continuation to achieve stability of radiofrequency catheter for right posteroseptal accessory pathway, and successfully abolished the preexcitation.

Ablación por radiofrecuencia de fibrilación auricular paroxística y persistente / Radiofrequency ablation of paroxysmal and persistent atrial fibrillation

La ablación por radiofrecuencia (ARF) es aceptada en la actualidad como tratamiento de la fibrilación auricular (FA) paroxística y persistente. El objetivo del presente trabajo es comparar los resultados de la ablación por radiofrecuencia con diferentes técnicas...

Radiofrequency catheter ablation (RFA) is one of the currently accepted treatments for paroxysmal and persistent atrial fibrillation (AF). Different approaches are currently used. To analyze the results of RFA in patients (pts.) with paroxysmal and persistent AF performing different techniques...

Impact of percutaneous transluminal septal myocardial ablation on refractory paroxysmal atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy.

Atrial fibrillation is commonly observed in patients with hypertrophic obstructive cardiomyopathy. Episodes of paroxysmal atrial fibrillation are often torturous and limit the quality of life by causing congestive heart failure, transient hypotension, or bradycardia. Control of paroxysmal atrial fibrillation in patients with hypertrophic obstructive cardiomyopathy is considered to be important for symptomatic improvement and prevention of the development to chronic atrial fibrillation. The authors report on 3 patients with hypertrophic obstructive cardiomyopathy who suffered from paroxysmal atrial fibrillation despite receiving medical treatment using antiarrhythmic agents. However, after undergoing percutaneous transluminal septal myocardial ablation, the incidence of episodes became significantly less frequent. Percutaneous transluminal septal myocardial ablation is normally performed for attenuating left ventricular obstruction by reducing the systolic anterior motion of the mitral leaflet. However, in these patients, this procedure was also effective in preventing supraventricular arrhythmia, probably by improving left ventricular diastolic dysfunction, smooth blood inflow into the left ventricular, and decreasing the pressure stress against the left atrial wall.

Pulmonary vein antrum not always coaxial to the pulmonary vein: a dimensional pitfall to the circumferential isolation technique.

BACKGROUND: The dimensions and electrophysiological characteristics of the antral region of human pulmonary veins (PVs) were investigated. METHODS AND RESULTS: Fifty-five consecutive patients with symptomatic paroxysmal atrial fibrillation underwent PV isolation targeting the PV antrum potentials with a 31 mm multielectrode basket catheter (MBC). The most distal and proximal electrode pairs along the MBC spline where radiofrequency ablation was carried out were identified and the longitudinal distance between those ablation sites (Ld) was measured. When the Ld was > or =6 mm, the PV antrum was defined as noncoaxial. In 56% of the left superior PVs, 42% of the right superior PVs, 63% of the left inferior PVs and 56% of the right inferior PVs, a noncoaxial PV antrum was identified. In each PV, the radiofrequency ablation delivery duration and energy to complete the PV antrum isolation were significantly larger in the PVs with a noncoaxial PV antrum than in those with a coaxial PV antrum. CONCLUSION: The PV antrum is noncoaxial to the PV in >50% of the PVs, a feature that may increase the complexity of the circumferential isolation technique.

Electrogram-guided isolation of the left superior vena cava for treatment of atrial fibrillation.

AIMS: Radiofrequency ablation targeting the pulmonary veins offers potential cure for patients with symptomatic paroxysmal atrial fibrillation (AF). Initiating ectopics can also arise from other sites including the major thoracic veins, vein of Marshall and more rarely, persistent left superior vena cava (LSVC). We report our experience with arrhythmogenic persistent LSVC initiating AF. METHODS AND RESULTS: The LSVC was present in four patients from an overall series of 204 patients undergoing AF ablation at our centre. All were males, mean age 50 +/- 11 years. All patients underwent pre-procedure transesophageal echocardiography. The mapping of the LSVC was performed with a circumferential mapping catheter following pulmonary vein isolation. Atrial ectopics from the LSVC were observed to initiate AF. Catheter ablation (power controlled mode; 65 degrees C and 30 W at irrigation flow rate of 30 mL/min) resulted in electrical isolation of the LSVC in all patients and was accompanied by termination of AF in one of four patients. There were no complications. All patients underwent multiple procedures (three procedures in one patient, two procedures in three patients). After a mean follow-up of 18 +/- 7 months (range 7-24 months), three of the four patients remained free of AF off antiarrhythmic medications. CONCLUSION: Arrhythmogenic foci within persistent LSVC can result in AF despite electrical isolation of pulmonary veins. This report demonstrates the importance of the LSVC as a potential source of atrial ectopics initiating and perpetuating AF.

Syncope in hypertrophic cardiomyopathy: mechanisms and consequences for treatment.

Hypertrophic cardiomyopathy (HCM) is an inherited disease with marked phenotypic variability that includes the extent of hypertrophy, the presence and severity of symptoms, and the natural history of the disease. Symptoms of impaired consciousness (syncope and pre-syncope) occur in approximately 15-25% of patients with hypertrophic cardiomyopathy (HCM). In young patients a history of recurrent syncope is associated with an increased risk of sudden death. Detailed investigations identify a probable mechanism in a minority of these, usually paroxysmal atrial fibrillation or ventricular tachycardia. In the majority, however, no likely mechanism is found despite extensive investigation. Although this may be the case, it is still of vital importance to exclude potentially treatable causes of syncope.

A permanent junctional reciprocating tachycardia with atypical location, treated with radiofrequency catheter ablation.

Permanent junctional reciprocating tachycardia (PJRT) is an incessant or almost incessant supraventricular tachycardia with a long RP interval, usually occurring in children and young adults. The differential diagnosis of PJRT includes an atrial tachycardia and atypical atrioventricular nodal reentrant tachycardia (AVNRT). The accessory pathways in PJRT are typically located in the posteroseptal region. We report a case of successful radiofrequency catheter ablation in a 28-year-old male patient with PJRT due to a left posterolateral accessory pathway.

[Painless myocardial ischemia as a risk factor of constantly relapsing paroxysms of cardiac fibrillation]. / Bezbolevaia ishemiia miokarda kak faktor riska nepreryvno retsidiviruiushchikh paroksozmov mertsatel'noi aritmii.

A case is reported illustrating relationship between marked coronary atherosclerosis with development of painless myocardial ischemia (PMI) and constantly recurrent paroxysms of cardiac fibrillation (CF). A male 62-year-old patient suffering from paroxysmal CF received cordaron in a dose 200 mg twice a day. The treatment was ineffective until a comprehensive examination (thyroid hormones, echocardiography, Holter ECG monitoring, treadmill test, CT of the coronary arteries) found PMI episodes and severe stenosing atherosclerosis and the treatment was changed for sotalex (80 mg twice a day). Sotalex treatment was effective and stopped recurrences of CF.

[Bouveret's tachycardia]. / Tachycardies de Bouveret.

In 1889, in an age preceding the invention of the electrocardiogram, a physician working in the hospitals of Lyon published a remarkable paper on essential paroxysmal tachycardia, of which Bristowe in England and Huppert in Germany had already spoken. The study described 12 cases (including 3 personal cases) of essential paroxysmal tachycardia and 6 secondary tachycardias. They were not all benign, there being 4 deaths out of the 12 cases. From this period on, the term "Bouveret's tachycardia" has been used in France and, with the advances in rhythmology, some have assimilated it to paroxysmal nodal tachycardia. In fact, many forms of paroxysmal essential tachycardia have been recognised at atrial (nodal tachycardia, accessory pathway tachycardia, idiopathic atrial flutter and fibrillation) and ventricular levels (benign or ventricular Bouveret's tachycardia). This is an occasion to review the variety of clinical medicine in the accuracy of a rhythmological diagnosis without forgetting that the electrocardiogram is essential when the recordings are analysable. The term of Bouveret's tachycardia should be retained but, before electrocardiographic analysis, it englobes all paroxysmal tachycardia occurring in healthy hearts, and not only paroxysmal nodal tachycardia.

Síndrome de Wolff-Parkinson-White / Wolff-Parkinson-Write syndrome

A avaliaçäo de pacientes com pré-excitaçäo ventricular é frequente nos consultórios de Cardiologia. Este artigo apresenta uma revisäo prática do manuseio clínico desses pacientes. Para tratarmos os pacientes com síndrome de Wolff-Parkinson-Write, devemos considerar os sintomas e o possível risco de morte súbita. Embora muito baixa, a incidência de morte súbita. Embora muito baixa, a incidência de morte súbita é maior nos sintomáticos (4 "por cento"). Pacientes assintomáticos apresentam apresentam risco de morte súbita de 1/1.000 anos-pacientes. A minoria dos pacientes com síndrome de Wolff-Parkinson-White é sintomática (20 "por cento). Os sintomas mais frequêntes säo crises de taquicardia supraventricular, que utilizam uma via acessória como parte do circuito macro-reentrante atrioventricular. O tratamento da crise de taquicardia ortodrômica pode ser feito com verapamil ou adenosina, caso as manobras vagais näo surtam efeito. O tratamento de escolha vagais para a reversäo das taquicardias antidrômicas e taquiarritmias atriais pré-excitadas é a cardioversäo elétrica, ou drogas do grupo 1A e 1C. A presença de fibrilaçäo atrial em portadores de via acessória com período refratário anterógrado curto gera uma frequência ventricular e consequente morte súbita. O tratamento definitivo para os pacientes sintomáticos com síndrome de Wolff-Parkinson-White é a ablaçäo por cateter com radiofrequência. Os pacientes assintomáticos devem ser avaliados com Holter, teste ergométrico e ecocardiograma, na tentativa de se identificar aqueles com maior risco de morte súbita. O estudo eletrofisiológico está indicado nos pacientes assintomáticos, nos quais há suspeita de maior risco de morte súbita. Se este for confirmado, a ablaçäo por cateter estará indicada. O estudo eletrofisiológico näo está indicado de maneira indiscriminada para todos os assintomáticos, apenas para os acima mencionados e para aqueles com risco pessoal ou coletivo.

Síndrome de preexcitación en el Hospital Juan XXIII La Paz / Pre-excitation syndrome at Hospital John XXIII of La Paz

Se presentan 4 casos de Síndrome de Preexcitación del Servicio de Cardiología del Hospital Juan XXIII en los años 1993 a 1996, analizandose la sintomatología con la cual se presentan y haciéndose énfasis en que la mayoria no presentaron alteraciones al examen cardiovascular, además se muestra la importancia del electrocardiograma de superficie para el diagnóstico de esta patología

Anatomy of atrioventricular nodal reentry investigated by intracardiac echocardiography.

Intracardiac echocardiography was used to evaluate posteroseptal space anatomy in patients with atrioventricular nodal reentrant tachycardia compared with patients with other mechanisms of tachycardia. The posteroseptal space was found to be significantly wider in patients with atrioventricular nodal reentry, suggesting an anatomic basis for dual atrioventricular nodal physiology.

Paroxysmal atrial fibrillation. A common but neglected entity.

Paroxysmal atrial fibrillation is an extremely common form of atrial fibrillation seen by most physicians. Despite making up more than 40% of the cases of atrial fibrillation, its management continues to be neglected in the medical literature. Many of the recent large-scale prospective trials have excluded these patients. Limited data suggest that paroxysmal atrial fibrillation should be treated in a similar fashion as chronic atrial fibrillation.

Catheter ablation of permanent junctional reciprocating tachycardia with radiofrequency current.

OBJECTIVES: This study evaluated accessory pathway location, its relation to retrograde P wave polarity on the surface electrocardiogram and radiofrequency ablation efficacy and safety in a large group of patients with permanent junctional reciprocating tachycardia. BACKGROUND: Permanent junctional reciprocating tachycardia is an uncommon form of reciprocating tachycardia, almost incessant from infancy and usually refractory to drug therapy. It is characterized by RP > PR interval and usually by negative P waves in leads II, III, aVF and V4 to V6. Retrograde conduction occurs through an accessory pathway with slow and decremental properties. Although this accessory pathway has been classically located in the posteroseptal zone, other locations have been recently reported. METHODS: The study included 32 patients (20 men, 12 women, mean [+/- SD] age 29 +/- 15 years) with a diagnosis of permanent junctional reciprocating tachycardia confirmed at electrophysiologic study. Seven patients had depressed left ventricular function. Radiofrequency energy was applied at the site of the earliest retrograde atrial activation during tachycardia. RESULTS: There were 33 accessory pathways. The site of the earliest retrograde atrial activation was posteroseptal in 25 patients (76%), midseptal in 4 (12%), right posterior in 1 (3%), right lateral in 1 (3%), left posterior in 1 (3%) and left lateral in 1 (3%). Thirty pathways were ablated with a right approach; in 11 patients with posteroseptal pathway the ablation was performed through the coronary sinus. Three pathways were ablated with a left approach. Positive retrograde P wave in lead I suggested that ablation could be performed from the right side; if negative, it did not exclude ablation from this approach. All the accessory pathways were successfully ablated, with a median of 3 and a mean of 5.6 +/- 5 radiofrequency applications of 70 +/- 26 s in duration. In two patients with the accessory pathway in the midseptal zone, a transient second- and third-degree atrioventricular block, respectively, was observed after ablation. At a mean follow-up of 18 +/- 12 months, 31 patients (97%) are asymptomatic without antiarrhythmic therapy (95% confidence interval [CI] 84% to 99%). Recurrences were observed in four patients (13%) (95% CI 4% to 29%), three of whom had the accessory pathway ablated successfully at a second session. All patients with depressed left ventricular function showed a marked improvement after successful ablation. CONCLUSIONS: In our experience, most of the patients with permanent junctional reciprocating tachycardia had posteroseptal pathways; all these pathways were ablated from the right side. P wave configuration may be helpful in suggesting the approach to the site of ablation. Catheter ablation using radiofrequency energy is an effective therapy for permanent junctional reciprocating tachycardia.

[Usefulness of the pre-excitation index to determine the mechanism of supraventricular paroxysmal tachycardia and the location of the anomalous pathway]. / Utilidad del índice de preexcitación para determinar el mecanismo de la taquicardia paroxística supraventricular y la localización de la vía anómala.

To evaluate the preexcitation index in determinate the mechanism of paroxysmal supraventricular tachycardia and localize accessory pathway, fifty nine patients with clinical and electrocardiographic supraventricular tachycardia were analyzed. There were thirty eight patients (64.4%) with orthodromic AV reentry using an accessory pathway for retrograde conduction and 21 patients (35.6%) with typical AV nodal reentrant tachycardia. Preexcitation of the atrium during tachycardia by premature ventricular complex at a time when anterograde His bundle activation was present in 30 o 38 (79%) patients with AV reentry while only 8 of 21 (38%) patients with AV nodal reentry demonstrated preexcitation during tachycardia. There was no significant difference between left and right accessory pathways and in mean tachycardia cycle length between the two groups. However, atrioventricular reentry demonstrated atrial preexcitation during tachycardia more frequently than AV nodal reentry. In conclusion, our findings show that the preexcitation index is a useful method for determinate the mechanism of supraventricular tachycardia and to localize accessory pathways.