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At least 19 recordsLinked to original sources
PubMed2004

Incremental value of isolating the right inferior pulmonary vein during pulmonary vein isolation procedures in patients with paroxysmal atrial fibrillation.

Electrical isolation of the left superior, left inferior, and right superior pulmonary veins (PVs) is often, but not always, effective in eliminating paroxysmal atrial fibrillation (PAF). The incremental clinical value of also isolating the right inferior PV has not been well defined. PV isolation by ostial applications of radiofrequency energy guided by PV potentials was performed in 176 consecutive patients (mean age 52 +/- 11 years) with PAF. The left superior, left inferior, and right superior PVs were targeted in 106 patients, and all four PVs were targeted 70 patients. Successful isolation was achieved in 96% of targeted PVs. The mean duration of follow-up was 15 +/- 7 months. At 1-year follow-up, 58% of patients in whom three PVs were isolated were free of recurrent PAF in the absence of antiarrhythmic drug therapy, compared to 73% of patients in whom all four PVs were isolated (P = 0.07). There is a trend towards a better outcome when all four PVs are isolated than when only the three major PVs are isolated. Whenever feasible, the right inferior PV should be isolated along with the other three PVs during the first ablation procedure in patients with PAF.

Adult↗
PubMed2006

Electrophysiology of pulmonary veins.

Pulmonary veins were found to be important foci for the genesis and maintenance of atrial fibrillation. Morphological studies have demonstrated the presence of complex anatomic structures and different types of cardiomyocytes in pulmonary veins. Numerous studies have suggested that the combination of reentrant and nonreentrant mechanisms (automaticity and triggered activity) are the underlying arrhythmogenic mechanisms of atrial fibrillation initiation from the pulmonary veins. Electropharmacological studies further indicated that pulmonary veins contained distinct arrhythmogenic activity. Several experimental models have been used to study the pulmonary vein electrical activity and demonstrate the precipitating factors for enhancing the pulmonary vein arrhythmogenic activity. The aim of this review article is to provide a critical overview of the current understanding of the basic and clinical electrophysiology of pulmonary veins and to underscore the importance of future research in this field.

Arrhythmias, Cardiac↗
PubMed2006

Pulmonary vein tachycardia after pulmonary vein isolation in patients with atrial fibrillation.

BACKGROUND: Pulmonary vein (PV) isolation has been developed to treat patients with atrial fibrillation (AF), and the electrophysiological endpoint of PV isolation is the disappearance or dissociation of pulmonary vein potentials (PVPs). Pulmonary vein tachycardia (PVT) is the dissociated PV rhythm with a rapid rate. However, the characteristics and significance of PVT after pulmonary vein isolation in patients with AF remains unclear. METHODS: From June 2003 to June 2005, a total of 285 consecutive patients with drug refractory AF were included in this study, and they underwent segmental pulmonary vein ablation (SPVA) or circumferential pulmonary vein ablation (CPVA). PV isolation was the initial endpoint for both approaches with documenting disappearance or dissociation of PVPs. PVT was characterized as dissociated activities within PVs with a circle length (CL) of < 300 ms, and was classified into organized PVT or disorganized PVT according to the variance of CL. Systematic follow-up was conducted after initial procedures. Continuous variables were analyzed by Student's t test and categorical variables were analyzed by chi-square test. RESULTS: Three hundred and fifteen PVs were ablated in 85 patients underwent SPVA approach, 400 circular lesions surrounding ipsilateral PVs (including 790 PVs) were produced in the rest of 200 patients received CPVA approach. Electrical isolation was achieved in all of these PVs. Of these, PVPs were abolished in 89.8% (992/1105) of the ablated PVs, dissociated PV rhythms were documented in the rest 10.2 % (113/1105) of the treated PVs. Among the 113 dissociated PV rhythms, 28 met the criteria of PVT with mean CL of (155 +/- 43) ms (2 PVTs in 2 patients received SPVA, 26 PVTs in 18 patients underwent CPVA). PVT was more frequently documented in patients underwent CPVA approach [9.0% (18/200) vs 2.3% (2/85), P = 0.04]. During the 6-month follow-up, it was indicated that no significant difference existed in AF free rate between patients with PVT and those without PVT (P = 0.75). CONCLUSIONS: PVT dissociated from LA activations can be documented after PV isolation, especially in patients underwent CPVA approach. However, PVT does not affect the follow-up results.

Adolescent↗
PubMed2006

Propofol and thiopental attenuate adenosine triphosphate-sensitive potassium channel relaxation in pulmonary veins.

Pulmonary veins (PV) make a significant contribution to total pulmonary vascular resistance. We investigated the cellular mechanisms by which the intravenous anesthetics propofol and thiopental alter adenosine triphosphate-sensitive potassium (KATP+) channel relaxation in canine PV. The effects of KATP+ channel inhibition (glybenclamide), cyclooxygenase inhibition (indomethacin), nitric oxide synthase inhibition (L-NAME), and L-type voltage-gated Ca2+ channel inhibition (nifedipine) on vasorelaxation responses to levcromakalim (KATP+ channel activator) alone and in combination with the anesthetics were assessed. The maximal relaxation response to levcromakalim was attenuated by removing the endothelium and by L-NAME, but not by indomethacin. Propofol (10(-5), 3x10(-5), and 10(-4) M) and thiopental (10(-4) and 3x10(-4) M) each attenuated levcromakalim relaxation in endothelium-intact (E+) rings, whereas propofol (3x10(-5) and 10(-4) M) and thiopental (3x10(-4) M) attenuated levcromakalim relaxation in endothelium-denuded (E-) rings. In E+ rings, the anesthesia-induced attenuation of levcromakalim relaxation was decreased after pretreatment with L-NAME but not with indomethacin. In E-strips, propofol (10(-4) M) and thiopental (3x10(-4) M) inhibited decreases in tension and intracellular Ca2+ concentration ([Ca2+]i) in response to levcromakalim, and these changes were abolished by nifedipine. These findings indicate that propofol and thiopental attenuate the endothelium-dependent component of KATP+ channel-induced PV vasorelaxation via an inhibitory effect on the nitric oxide pathway. Both anesthetics also attenuate the PV smooth muscle component of KATP+ channel-induced relaxation by reducing the levcromakalim-induced decrease in [Ca2+]i via an inhibitory effect on L-type voltage-gated Ca2+ channels.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2000

Mediators of alkalosis-induced relaxation of piglet pulmonary veins.

Pulmonary venous constriction leads to significant pulmonary hypertension and increased edema formation in several models using newborns. Although alkalosis is widely used in treating neonatal and pediatric pulmonary hypertension, its effects on pulmonary venous tone have not previously been directly measured. This study sought to determine whether alkalosis caused pulmonary venous relaxation and, if so, to identify the mediator(s) involved. Pulmonary venous rings (500-microm external diameter) were isolated from 1-wk-old piglets and precontracted with the thromboxane mimetic U-46619. Responses to hypocapnic alkalosis were then measured under control conditions after inhibition of endothelium-derived modulator activity or K(+) channels. In control rings, alkalosis caused a 34.4 +/- 4.8% decrease in the U-46619-induced contraction. This relaxation was significantly blunted in rings without functional endothelium and in rings treated with nitric oxide synthase or guanylate cyclase inhibitors. However, neither cyclooxygenase inhibition nor voltage-dependent, calcium-dependent, or ATP-dependent K(+)-channel inhibitors altered alkalosis-induced relaxation. These data suggest that alkalosis caused significant dilation of piglet pulmonary veins that was mediated by the nitric oxide-cGMP pathway.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2005

Conventional and sutureless techniques for management of the pulmonary veins: Evolution of indications from postrepair pulmonary vein stenosis to primary pulmonary vein anomalies.

OBJECTIVE: We have previously reported a limited but favorable experience with a novel sutureless technique for surgical management of postoperative pulmonary vein stenosis occurring after repair of total anomalous pulmonary venous drainage. Because this technique requires integrity of the retrocardiac space for hemostasis, extension of the technique to the primary repair of pulmonary vein anomalies requires evaluation. This analysis reviews our experience with the sutureless technique in patients with postrepair pulmonary vein stenosis, as well as our extension of the technique into primary repair of pulmonary vein anomalies. METHODS: Retrospective univariable-multivariable analysis of all pulmonary vein stenosis procedures and sutureless pulmonary vein procedures over a 20-year period was performed. Cox proportional hazards modeling was used to identify variables associated with freedom from reoperation or death. RESULTS: Sixty patients underwent 73 procedures, with pulmonary vein stenosis present in 65 procedures. The sutureless technique was used in 40 procedures. Freedom from reoperation or death at 5 years after the initial procedure was 49%. Unadjusted freedom from reoperation or death was greater with the sutureless technique for patients with postrepair pulmonary vein stenosis ( P = .04). By using multivariable analysis, a higher pulmonary vein stenosis score was associated with greater risk of reoperation or death. After adjustment, the sutureless repair was associated with a nonsignificant trend toward greater freedom from reoperation or death ( P = .12). Despite the absence of retrocardiac adhesions, operative mortality was not increased with the sutureless technique ( P = .64). Techniques to control bleeding (intrapleural hilar reapproximation) and improve exposure (inferior vena cava division) were identified. CONCLUSION: The sutureless technique for postrepair pulmonary vein stenosis is associated with encouraging midterm results. Extension of the indications for the technique to primary repair appears safe with the development of simple intraoperative maneuvers.

Analysis of Variance↗
PubMed2006

Clinical predictors and outcomes associated with acute return of pulmonary vein conduction during pulmonary vein isolation for treatment of atrial fibrillation.

BACKGROUND: Pulmonary vein electrical isolation (PVI) is an effective treatment for atrial fibrillation (AF). However, recurrence of pulmonary vein (PV) conduction after ablation may limit long-term success. OBJECTIVE: We sought to determine the clinical predictors of acute PV reconnection during PVI and assess the long-term clinical outcomes associated with this phenomenon. METHODS: We studied all patients with AF referred for PVI between November 2000 and August 2004. Over the course of the study period, PVI of arrhythmogenic PVs was performed segmentally using a 4-mm tip (52 degrees , 40 W, up to 90 seconds) or 8-mm tip catheter (50 degrees , 70 W, up to 60 seconds). PVI was defined as entry and exit block using a multipolar Lasso catheter. All veins were resampled to confirm isolation after 20-60 minutes. AF control was defined as no AF on or off a previously ineffective antiarrhythmic drug. Follow-up data included transtelephonic monitoring and clinical data collection from patient interviews. RESULTS: There were 424 patients who underwent isolation of 1,347 PVs during the study period. Acute reconnection of at least one PV occurred in 211 (50%) of the 424 patients and 326 (24%) of 1,347 of the PVs targeted. The left superior PV was most likely to acutely recover conduction compared with the other veins (left superior 31%, right superior 26%, right inferior 22%, left inferior 24%; P = .03). Patients with acute reconnection were more likely to be older, have a larger left atrium, have a history of hypertension or obstructive sleep apnea, and demonstrate persistent AF. After a single procedure, AF control was achieved in 153 (70%) of the 213 patients who demonstrated acute PV reconnection compared with 148 (73%) of 211 patients without acute PV reconnection observed (P = .52). CONCLUSIONS: Acute return of PV conduction is common after successful PVI and is more likely to occur in older patients with nonparoxysmal AF, hypertension, a large left atrium, and sleep apnea. There was no significant difference in acute PV reconnection between the 4-mm and 8-mm tip RF catheter despite differences in power and duration of energy delivery. Furthermore, there was no effect of PV reconnection on long-term AF control after repeated disconnection was performed.

Atrial Fibrillation↗
PubMed1993

Fifteen micrometer microspheres reflux up the pulmonary veins during pulmonary artery occlusion.

The systemic arterial blood supply to the lung (bronchial blood flow, Qbr) is commonly measured using the reference flow technique by injecting radiolabeled microspheres into the left atrium (LA) and simultaneously collecting a reference blood sample from a large artery such as the aorta. These measurements are often done with the pulmonary artery occluded prior to the time of injection. We have reported previously that left atrial blood refluxes up the pulmonary veins following pulmonary artery (PA) occlusion. We designed this experiment to determine if 15 mu microspheres reflux from the LA into the left lung (i) when the left PA is occluded prior to microsphere injection and (ii) when the left PA is open during the injection. We calculated Qbr to the left lung after simultaneous left ventricular (LV) and LA injections of different radiolabeled microspheres in anesthetized, closed-chest, prone goats. When the PA was open (but occluded 5 sec after the microsphere injection), Qbr calculated from an LA injection differed little from that calculated from an LV injection of microspheres. However, when the PA was occluded prior to injection of the microspheres, Qbr calculated from an LA injection was significantly higher than that calculated from an LV injection suggesting that microspheres reflux from the LA to the lung.

Animals↗
PubMed2005

[Clinical significance of the doppler evaluation in ductus venosus, hepatic veins and pulmonary veins].

Doppler evaluation of the fetal venous system at present improves assessment of fetal well-being in many conditions. Actually, analysis of ductus venosus waveforms seems to be the most important. It place role in detection of genetic abnormalities (in low pregnancies), prediction of outcomes growth-restricted fetuses, assessment of severity of heart failure due to congestive heart anomalies, fetal infections, hydrops fetalis. Hepatic veins are known rather as an additional parameter (for ductus venosus) in the severely compromised fetus. Doppler evaluation of pulmonary veins may be useful in prediction of fetal lung maturity and in detection some difficult circulatory anomalies.

Female↗
PubMed1981

Anomalous unilateral single pulmonary vein mimicking pulmonary varices.

Anomalous single pulmonary veins (AUSPV) is a rare anomaly of the pulmonary venous system. Six cases have been documented in the literature, and two additional are reported here. Since AUSPV mimics pulmonary varices on pulmonary angiography, careful interpretation of the pulmonary venous anatomy by bidirectional and stereoscopic angiography is mandatory for diagnosing this anomaly.

Adult↗
PubMed2002

Differentiation of atrial and pulmonary vein potentials recorded circumferentially within pulmonary veins.

INTRODUCTION: Accurate discrimination of atrial and pulmonary vein potentials recorded circumferentially within the pulmonary veins is important when performing segmental isolation of the pulmonary veins in patients with atrial fibrillation. METHODS AND RESULTS: Twenty patients with paroxysmal atrial fibrillation underwent pulmonary vein mapping with a decapolar Lasso catheter during sinus rhythm and during pacing in the distal coronary sinus and left atrial appendage. Bipolar and unipolar electrograms were recorded within the left superior, right superior, and left inferior pulmonary veins. The atrial potentials were larger in the left pulmonary veins than in the right superior pulmonary vein, whereas the pulmonary vein potentials in the superior pulmonary veins were larger than in the left inferior pulmonary vein. The atrial and pulmonary vein potentials usually were readily distinguished during sinus rhythm in the right superior pulmonary vein. Characteristic distribution and morphologies of the atrial potentials as well as the response to distal coronary sinus and left atrial appendage pacing were useful for differentiating the atrial and pulmonary vein potentials in the left pulmonary veins. CONCLUSION: Atrial and pulmonary vein potentials recorded circumferentially within the pulmonary veins have characteristic features that are useful in distinguishing them from each other. In the left pulmonary veins, discrimination of the atrial and pulmonary vein potentials is aided by coronary sinus or left atrial appendage pacing.

Analysis of Variance↗
PubMed1996

[Flow in pulmonary veins].

Pulmonary venous flow can be evaluated by means of pulsed Doppler echocardiography during a transthoracic or transesophageal echocardiography examination. In most cases a three-peak spectral curve with highest positive wave during ventricular systole, a lower positive wave during ventricular diastole and a small negative wave during the left atrial contraction are recorded. Multiple factors affect the systolic and diastolic components of pulmonary venous flow. Pulmonary venous flow measurement may prove to be an important tool in routine judgment of diastolic left ventricular and atrial function. With regard to clinical importance, the pulmonary venous flow is a useful parameter for left atrial pressure quantification and for differential diagnosis of restrictive cardiomyopathy and constrictive pericarditis.

Blood Flow Velocity↗