The dormant epicardial reconnection of pulmonary vein: an unusual cause of recurrent atrial fibrillation after pulmonary vein isolation.

The case of a 65-year-old man with recurrent atrial fibrillation after undergoing segmental pulmonary vein isolation caused by the reconnection of previously isolated pulmonary veins is herein reported. Interestingly, frequent ectopic firings in the left superior pulmonary vein conducted to the left atrium, not through its ostium but through the supposed epicardial pathway at the region of the Marshall ligament, which had been absent during the first treatment session. The reisolation of the left superior pulmonary vein by radiofrequency application in the left atrial appendage thus successfully eliminated the occurrence of atrial fibrillation.

Decreased renal function as an independent predictor of re-hospitalization for congestive heart failure.

BACKGROUND: Patients with congestive heart failure (CHF) are often re-hospitalized, worsening both their quality of life and prognosis. Although renal dysfunction reportedly increases the risk of CHF, the association between renal dysfunction and re-hospitalization for CHF remains unclear. METHODS AND RESULTS: Patients with CHF and decreased renal function were reviewed. The estimated glomerular filtration rate (GFR) was calculated with the Modification of Diet in Renal Disease equation. Patients with decreased renal function (estimated GFR on admission <45 ml .min(-1) . 1.73 m(-2)) were re-hospitalized more frequently than were patients with preserved renal function (estimated GFR on admission >or=45). Patients with decreased renal function were older and had higher rates of anemia, worsening renal function during hospitalization, and previous hospitalization for CHF. Independent predictors of re-hospitalization for CHF identified with multivariate analysis were age, previous hospitalization for CHF, decreased renal function, and non-use of an angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker. CONCLUSIONS: Renal dysfunction is an independent predictor of re-hospitalization for CHF, so careful follow-up is needed, even after discharge.

Renal insufficiency is related to painless myocardial infarction.

BACKGROUND: Acute myocardial infarction (MI) sometimes occurs without painful symptoms and in such cases, prognosis is worsened by delays in diagnosis and revascularization. Renal insufficiency induces many types of neuropathy, but the relation between renal insufficiency and painless MI remains unclear. METHODS AND RESULTS: Patients with MI and elevated creatine kinase levels were retrospectively analyzed. Renal insufficiency (serum creatinine concentration > or =1.5 mg/dl) and other characteristics (age, sex, body mass index, hypertension, smoking, diabetes mellitus, dyslipidemia, history of stroke, previous MI, hemodialysis, and atrial fibrillation) were compared between patients who had MI with painful symptoms (painful MI, n=131) and patients who had MI without painful symptoms (painless MI, n=18). Other variables compared were the time from symptom onset to admission, peak creatine kinase concentration, Killip class, site of MI, emergency coronary angiography, postprocedural Thrombolysis In Myocardial Infarction grade III flow, and in-hospital death. Univariate analysis identified older age, renal insufficiency, and previous MI as predictors of painless MI. Patients with painless MI showed higher rates of Killip class > or =II and in-hospital death and a longer time from symptom onset to admission. However, multivariate analysis identified only renal insufficiency as an independent predictor of painless MI. CONCLUSIONS: MI without painful symptoms frequently develops in patients who have renal insufficiency, so the possibility of painless MI should be evaluated in such patients to ensure early diagnosis and treatment.

Reduction of AF recurrence after pulmonary vein isolation by eliminating ATP-induced transient venous re-conduction.

BACKGROUND: Recent evidence has suggested that the transient re-conduction of the isolated pulmonary vein (PV) induced by the intravenous injection of adenosine (dormant PV conduction) might predict the incidence of subsequent venous reconnection after the procedure, which is the main cause of the atrial fibrillation (AF) recurrence after PV isolation (PVI). We tested the hypothesis that the elimination of these dormant PV conductions by additional radiofrequency (RF) applications can improve the efficacy of the PVI. METHODS AND RESULTS: One hundred forty-eight patients (124 males; mean age 53 +/- 9 years) with drug-refractory AF underwent the PVI procedure. The standard PVI was performed in 94 patients (Group A), whereas the elimination of adenosine triphosphate (ATP)-induced dormant conduction using additional RF energy was performed in addition to the standard PVI in other 54 patients (Group B). Dormant conduction was observed in 56% of the patients (30/54) in Group B and 95% of these transient re-conductions were successfully eliminated by additional RF applications (mean: 1.5 +/- 1.0 times). During the mean follow-up period of 20 months, recurrences of AF after the procedures were observed significantly less frequently in Group B (20%) than in Group A (40%) (P < 0.05). CONCLUSION: The use of additional RF applications to eliminate transient PV reconnection induced by ATP injection led to a reduction of AF recurrence after PVI, most likely due to the minimization of the subsequent PV reconnection.

Segmental pulmonary vein antrum isolation using the "large-size" lasso catheter in patients with atrial fibrillation.

BACKGROUND: The limited efficacy and complications of segmental ostial pulmonary vein isolation (PVI) for treating atrial fibrillation (AF) have been discussed so, in the present study the feasibility and efficiency of performing segmental pulmonary vein (PV) antrum isolation to treat AF were assessed. METHODS AND RESULTS: A total of 187 patients with drug-refractory AF (paroxysmal 120, persistent 67) underwent segmental PVI guided by circumferential 20-electrode catheters (Lasso). Radiofrequency (RF) current was delivered either at the ostium using a regular Lasso (15-20 mm in diameter, 70 patients: Group 1) or at the antrum using a larger Lasso (25-30 mm in diameter, 117 patients: Group 2). A significantly wider region had to be ablated, with a longer RF application time, to isolate all 4 PVs in Group 2 patients than in Group 1 patients. Although the rate of recurrence of AF after the initial session was equal in both groups, a significantly greater number of patients were free from AF after a mean of 1.4 procedures in Group 2 than in Group 1 (93% vs 76% for paroxysmal AF, 78% vs 48% for persistent AF). CONCLUSIONS: Segmental antral PVI using large-sized Lasso catheters was found to be more effective and safer than ostial PVI for the treatment of AF.

The effects of pulmonary vein isolation on the morphology of p waves: the contribution of pulmonary vein muscle excitation to the formation of p waves.

BACKGROUND: Although the pulmonary veins have been demonstrated to play an important role in initiating and perpetuating atrial fibrillation, the role that cardiac muscle tissue in the pulmonary veins plays regarding the formation of P wave remains to be elucidated. We sought to clarify the contribution of pulmonary vein cardiac muscles to the formation of P waves by analyzing the P loops/waves in patients with atrial fibrillation. METHODS: The subjects in this study consisted of 21 patients (mean age, 57 +/- 10 years) with drug-refractory, paroxysmal atrial fibrillation who had undergone a segmental ostial isolation of all four pulmonary veins from the left atrium. Vectorcardiograms, intracardiac electrograms, and electrocardiograms (ECGs) were recorded before and after pulmonary vein isolation. RESULTS: The morphology of P waves changed after pulmonary vein isolation procedures with a significant increase in the maximal amplitude of both the leftward force in lead x and the anterior force in lead z (P < 0.05). The middle part (second one of three parts) of P loop on the horizontal plane shifted anteriorly and leftward after pulmonary vein isolation. Intracardiac electrograms in the pulmonary veins demonstrated the averaged activation times of all four pulmonary veins to range from 40% to 84% of the P duration. CONCLUSIONS: The excitation of cardiac muscle tissue, which has migrated to the pulmonary veins, was thus found to play an important role in the formation of the middle part of the P wave/loop.

Behavior of atrial ectopic beats before and after pulmonary vein isolation in patients with atrial fibrillation: a reduction in the number and arrhythmogenicity of ectopic firings.

BACKGROUND: No studies evaluating in a quantitative manner the effect of pulmonary vein (PV) isolation on the behavior of atrial premature beats have been reported. OBJECTIVES: The purpose of this study was to reveal the behavior of atrial premature beats before and after PV isolation in patients with paroxysmal atrial fibrillation (AF). METHODS: In 108 patients free from AF following PV isolation, both the number of atrial premature beats and their coupling intervals before and following PV isolation were evaluated with periodic 24-hour ambulatory monitoring. RESULTS: After a successful PV isolation procedure (group 1, n = 78), the number of atrial premature beats significantly decreased with two distinct time courses: an acute reduction on the following day and a subsequent gradual decrease throughout the whole observation period. The mean atrial premature beat coupling interval at baseline was 420 +/- 30 ms, which was significantly prolonged to 560 +/- 100 ms at 3 months after PV isolation (P <.01). Although patients with AF recurrence after PV isolation (group 2, n = 30) had transiently depressed atrial premature beats shortly after the procedure, they recovered to the former level 3 months after PV isolation. Repeat PV isolation targeting the reconnected PVs successfully suppressed these residual atrial premature beats both in their number and the coupling interval in a manner similar to those in group 1. CONCLUSION: Successful PV isolation reduced the number of atrial premature beats with both rapid and gradual time courses. The residual atrial premature beats appeared less arrhythmogenic, with longer coupling intervals than those at baseline. AF recurrences after PV isolation were associated with increased atrial premature beat number and shortened coupling interval, which were depressed by reisolation of reconnected PVs.

Dual mechanisms underlying pulmonary vein tachycardias in a patient with paroxysmal atrial fibrillation.

We report a case of a 46-year-old man with paroxysmal atrial fibrillation who underwent pulmonary vein isolation. After a complete isolation of each pulmonary vein was performed, two different types of pulmonary vein tachycardia appeared: a regular tachycardia in the left inferior pulmonary vein with a supposed reentrant mechanism, and an irregular tachycardia in the right superior PV showing a nonreentrant character.