Multiple Pulmonary Vein Research Articles

Clinical features and CT findings of fibrosing mediastinitis associated pulmonary hypertension

Objective: To investigate the clinical features and CT findings of pulmonary hypertension (PH) in patients with fibrosing mediastinitis (FM). Methods: Thirteen patients with FM diagnosed between September 2015 and June 2022 were studied retrospectively, including patients with PH (FM-PH group) and patients without PH (FM group) confirmed on right heart catheterization. The t test of two independent samples, Mann-Whitney U rank sum and Fisher's test were used to compare the general information, symptoms, laboratory examination, right ventricular and pulmonary artery measurement data and pulmonary artery CT findings between the two groups, respectively. Results: Compared with the 7 FM patients aged 28-79 (60.00±17.69) years, the 6 patients in the FM-PH group, aged from 60 to 82 (68.83±8.35) years, had more peripheral edema, lower percentage of PaO2, wider inner diameters of pulmonary artery and right ventricle, a higher ratio of right ventricle and left ventricular transverse diameter, faster tricuspid regurgitation velocity and higher estimated systolic pulmonary artery pressure (P<0.05). There were no differences in BNP levels and tricuspid annular plane systolic excursion between groups (P>0.05). Of the 6 patients with PH, 5 had precapillary PH and 1 had mixed PH. Except that the pulmonary vascular resistance in patients of the FM-PH group was significantly higher than that in the FM group (P<0.05), there were no significant differences in cardiac output, mixed venous oxygen saturation and pulmonary capillary wedge pressure between the two groups. CT pulmonary angiography (CTPA) showed pulmonary artery and vein stenosis. Patients in the FM-PH group had more severe stenosis and occlusion of pulmonary artery and pulmonary vein (P<0.05), and more involvement of multiple pulmonary veins (P<0.05). Conclusions: The clinical manifestation of FM complicated with PH is related to the degree of involvement of pulmonary artery, vein and airway. It is recommended that the disease be evaluated in combination with multiple parameters such as clinical manifestations, cardiac ultrasound, right cardiac catheter and CTPA.

Characterization of pulmonary vein reconnection post Cryoballoon ablation

BackgroundThe Arctic Front Cryoballoon System is a technology in which substrate alterations in patients with atrial fibrillation (AF) recurrence have not been well characterized. In this study, we evaluated sites of pulmonary vein (PV) reconnections and the accuracy of the Achieve™ circular mapping catheter in detecting these reconnections after cryoablation. MethodsThis study included 15 patients undergoing redo AF ablation after a prior single cryoablation procedure. PV reconnection sites were determined by measuring PV signals and high output pacing from 4 vectors of the Achieve catheter. The results were compared with a roving mapping catheter guided by rotational intracardiac echocardiography (ICE) in the left atrium. ResultsAll patients had PV reconnections (2.1 ± 0.8 veins/patient). The left superior PV was most commonly reconnected (n = 11), whereas the right inferior PV was least likely (n = 3). Both carinas (left: n = 11; right: n = 7) and left atrial appendage ridge (n = 11) were also frequently reconnected. Mapping with the Achieve catheter showed a positive predictive value (PPV) 100% and negative predictive value (NPV) 96% when compared with ICE guided mapping. In 2 patients, right superior PV reconnection was not identified by the Achieve. ConclusionDuring redo AF ablation after index cryoablation, multiple PVs are usually reconnected, with both carinas and left atrial appendage ridge being common sites of reconnection. The Achieve mapping catheter was able to identify reconnection with high positive and negative predictive values.

Comprehensive surgical approach to treat atrial fibrillation in patients with variant pulmonary venous anatomy

Catheter radiofrequency ablation procedures yield fairly successful results for the treatment of atrial fibrillation; however, patients with anatomic variant pulmonary veins (PV) are generally thought not to benefit from catheter ablation technique, with recurrence rates observed as high as 78%. We report a comprehensive surgical approach to treat this subset of patients with a modified full maze procedure. From January 2002 to December 2009, 72 patients undergoing cardiac surgery who had drug-refractory and/or recurrent AF after catheter ablation were identified. PV variance was observed on preoperative multislice chest computed tomography. All patients underwent multiple PV epicardial circumferential isolation and epicardial-endocardial longitudinal PV ablations along with standard maze as an adjunct to the cardiac surgical procedure. Patients were followed up at 6 months, 1 year, and 2 years postoperatively. Typical patterns of PV variation were observed in 72 patients. Left common PV trunk was found in 49 patients (68%), with a mean length of 21 ± 4.6 mm, diameter of 28.6 ± 4.9 mm, and wall thickness of 2.1 ± 1.7 mm. Right PV variants, including right middle and right top PVs, were found in 23 patients (32%), with a length of 20 ± 2.1 mm, diameter of 9.9 ± 3.4 mm, and wall thickness of 1.9 ± 1.7 mm. Overall restoration of sinus rhythm was confirmed in 64 patients (94%) at 1-year follow-up. Twelve patients were defibrillated into sinus rhythm within 90 days after the operation. A modified full maze procedure should be considered as a first choice treatment for atrial fibrillation with variant drainage of PVs because of the nature of PV size, wall thickness, and specific foci in the arrhythmogenic veins. Multiple PV isolation and epicardial-endocardial longitudinal PV ablations along with the standard maze are essential to success. Early referral for surgical ablation allows higher success rates.

Distinct restitution properties in vagally mediated atrial fibrillation and six-hour rapid pacing-induced atrial fibrillation

The atrial potential duration (APD) restitution has been suggested to play an important role in ventricular fibrillation; however, its role in atrial fibrillation (AF) has not been determined. This study sought to investigate the APD restitution properties in two different AF models: vagally mediated AF and 6-h rapid atrial pacing-induced AF. Twenty anaesthetized open-chest dogs were assigned to Group I, vagally mediated AF (n= 8) or Group II, 6-h rapid atrial pacing-induced AF (n= 12). In both groups, the monophasic APD was subsequently recorded at multiple pulmonary vein and atrial sites. The APD restitution curve was constructed using a dynamic pacing protocol and determined by plotting each APD(90) against the preceding diastolic interval at incremental atrial pacing rates at eight sites. In Group I, vagal stimulation significantly shortened the APD(90), flattened the APD restitution curve (slopes <1), and suppressed the APD alternans at each site, while increasing the AF inducibility and duration (P<0.05 for all). In Group II, 6-h rapid pacing-induced APD shortening steepened the restitution curves (slopes >1), facilitated the APD alternans, and also increased the incidence and duration of AF (P< 0.05 for all). The spatial dispersion of APD restitution was significantly increased in both groups. This study showed distinct atrial APD restitution properties in vagally mediated AF and 6-h rapid pacing-induced AF, indicating specific restitution kinetics in different mechanisms of AF.

Characterization of conduction recovery after pulmonary vein isolation using the “single big cryoballoon” technique

Pulmonary vein isolation using the cryoballoon technique (CB-PVI) has evolved into a simple and safe alternative for point-by-point radiofrequency ablation. Systematic analysis of conduction recovery occurring after CB-PVI and causing recurrent atrial fibrillation has not yet been performed. The purpose of this study was to analyze conduction recovery after PVI using the single big (28-mm) cryoballoon technique. Twenty-six patients with recurrent atrial tachyarrhythmia after previous CB-PVI underwent repeat ablation. Pulmonary vein (PV) reisolation was performed by antral irrigated radiofrequency ablation using electroanatomic mapping. For analysis of the location of conduction gaps, the ipsilateral LA-PV junction was divided into six equally distributed segments. PV reconduction frequently occurred into multiple (>2) PVs (54% patients). Conduction gaps could be abolished by single point ablation in 63% (lateral) and 41% (septal) of patients or by incomplete circular lesions in the remaining patients. A significantly higher number of patients exhibited conduction recovery at inferior segments (85% lateral, 77% septal) compared with superior segments (42% lateral, 31% septal). Furthermore, the ridge between PV ostia and left atrial appendage (LAA) was highly associated with reconduction into lateral PVs (81% of patients). Retrospective analysis of the initial CB-PVI-procedure revealed lower freezing temperatures at superior than inferior PVs as well as sharp catheter angulations with loss of central cryoballoon alignment to reach inferior PVs. Conduction recovery after CB-PVI occurs at a high incidence at inferior sites around ipsilateral PV ostia and the LAA-PV ridge. Modifications of the technique to ensure optimal balloon-tissue contact at predilection sites may improve long-term success rates.

A Case with Catecholaminergic Polymorphic Ventricular Tachycardia Unmasked after Successful Ablation of Atrial Tachycardias from Pulmonary Veins

Catecholaminergic polymorphic ventricular tachycardia (VT) is characterized by polymorphic VT during exercise, and the association of atrial fibrillation (AF) has been reported. However, the mechanism of AF in this disease and the relationship between VT and AF has been obscured. We described a 13-year-old girl who referred for catheter ablation of exercise-induced paroxysmal AF. Multifocal atrial tachycardia mimicking AF on the surface electrocardiogram originated from multiple pulmonary veins (PVs). While AT became non-inducible after the isolation of four PVs, polymorphic VT was initiated by isoproterenol infusion. Polymorphic VT was suppressed during rapid atrial pacing.

Radiofrequency Catheter Ablation of Atrial Fibrillation in Athletes Referred for Disabling Symptoms Preventing Usual Training Schedule and Sport Competition

Atrial fibrillation (AF) may occasionally affect athletes by impairing their ability to compete, and leading to noneligibility at prequalification screening. The impact of catheter ablation (CA) in restoring full competitive activity of athletes affected by AF is not known. The aim of our study was to investigate the effectiveness of CA of idiopathic AF in athletes with palpitations impairing physical performance and compromising eligibility for competitive activities. Twenty consecutive competitive athletes (all males; 44.4 +/- 13.0 years) with disabling palpitations on the basis of idiopathic drug-refractory AF underwent 46 procedures (2.3 +/- 0.4 per patient) according to a prospectively designed multiprocedural CA approach that consolidates pulmonary veins (PV) isolation through subsequent steps. Preablation, effort-induced AF could be documented in 13 patients (65%) during stress ECG and significantly reduced maximal effort capacity (176 +/- 21 W), as compared with patients with no AF during effort (207 +/- 43 W, P < 0.05). At the end of CA protocol, which also included ablation of atrial flutter (AFL) in 7 patients, 18 (90.0%) patients were free of AF and two (10.0%) reported short-lasting (minutes) episodes of palpitations during 36.1 +/- 12.7 months follow-up. Compared with preablation, postablation maximal exercise capacity significantly improved (from 183 +/- 32 to 218 +/- 20 W, P < 0.02). All baseline quality of life (QoL) parameters pertinent to physical activity significantly improved (P < 0.05) at the end of CA protocol. All athletes obtained reeligibility and could effectively reinitiate sport activity. AF, alone or in combination with AFL, may significantly impair maximal effort capacity thereby limiting competitive performance. Multiple PV isolation proved very effective in these patients to restore full competitive activity and allow reeligibility.

Thoracic exploration for the diagnosis of multiple pulmonary vein varices: case report

Thoracic exploration for the diagnosis of multiple pulmonary vein varices: case report

Worldwide Survey on the Methods, Efficacy, and Safety of Catheter Ablation for Human Atrial Fibrillation

The purpose of this study was to conduct a worldwide survey investigating the methods, efficacy, and safety of catheter ablation (CA) of atrial fibrillation (AF). A detailed questionnaire was sent to 777 centers worldwide. Data relevant to the study purpose were collected from 181 centers, of which 100 had ongoing programs on CA of AF between 1995 and 2002. The number of patients undergoing this procedure increased from 18 in 1995 to 5050 in 2002. The median number of procedures per center was 37.5 (range, 1 to 600). Paroxysmal AF, persistent AF, and permanent AF were the indicated arrhythmias in 100.0%, 53.0%, and 20.0% of responding centers, respectively. The most commonly used techniques were right atrial compartmentalization between 1995 and 1997, ablation of the triggering focus in 1998 and 1999, and electrical disconnection of multiple pulmonary veins between 2000 and 2002. Of 8745 patients completing the CA protocol in 90 centers, of whom 2389 (27.3%) required >1 procedure, 4550 (52.0%; range among centers, 14.5% to 76.5%) became asymptomatic without drugs and another 2094 (23.9%; range among centers, 8.8% to 50.3%) became asymptomatic in the presence of formerly ineffective antiarrhythmic drugs over an 11.6+/-7.7-month follow-up period. At least 1 major complication was reported in 524 patients (6.0%). The findings of this survey provide a picture of the variable and evolving methods, efficacy, and safety of CA for AF as practiced in a large number of centers worldwide and may serve as a guide to clinicians considering therapeutic options in patients suffering from this arrhythmia.

Mechanistic significance of intermittent pulmonary vein tachycardia in patients with atrial fibrillation.

The significance of intermittent tachycardia within a pulmonary vein (PV) during an episode of atrial fibrillation (AF) is unclear. The aim of this study was to determine the role that intermittent PV tachycardias play in AF. In 56 patients with AF, segmental ostial ablation guided by PV potentials was performed to isolate the PVs. The characteristics of intermittent PV tachycardias and the inducibility of AF before and after PV isolation were analyzed prospectively. During AF, a PV tachycardia (mean cycle length 130 +/- 30 msec) with exit block to the left atrium was present in 93% of left superior, 80% of left inferior, 73% of right superior, and 7% of right inferior PVs. The site of shortest cycle length during AF alternated between the PVs and left atrium 1 to 13 times per minute. Complete isolation was achieved in 168 (94%) of 178 targeted PVs. In 99% of PVs, tachycardia resolved upon isolation. AF was persistent before and after PV isolation in 100% and 27% of patients, respectively (P < 0.001). Intermittent bursts of tachycardia are observed within multiple PVs during persistent AF in a majority of patients. After PV isolation, PV tachycardias almost always resolve, and AF is less likely to be inducible or persistent. These observations suggest a dynamic interplay between the atria and PVs, with intermittent bursts of PV tachycardia being dependent on left atrial input and with the probability of persistent AF diminishing when PV tachycardias are eliminated by PV isolation.

Prevalence and significance of exit block from multiple pulmonary veins in patients with paroxysmal atrial fibrillation Hakan Oral, Christian Sticherling, Robert L. Baker, Steven P. Chough, Kristina Wasmer, Hiroshi Tada, Frank Pelosi, Jr., Bradley P. Knight, S. Adam Strickberger, Fred Morady. University of Michigan, Ann Arbor, MI

Prevalence and significance of exit block from multiple pulmonary veins in patients with paroxysmal atrial fibrillation Hakan Oral, Christian Sticherling, Robert L. Baker, Steven P. Chough, Kristina Wasmer, Hiroshi Tada, Frank Pelosi, Jr., Bradley P. Knight, S. Adam Strickberger, Fred Morady. University of Michigan, Ann Arbor, MI

Mapping-guided ablation of pulmonary veins to cure atrial fibrillation

Catheter ablation of triggers inducing paroxysms of atrial fibrillation (AF) is an emerging therapy for this common arrhythmia. In a series of 225 consecutive patients with AF resistant to multiple drugs, 96% presented with triggering foci originating from 1 or multiple pulmonary veins (PV), independently of whether or not the patient had ectopy or structural heart disease. The present article describes the mapping and ablation techniques applicable to individual patients: (1) criteria to define an arrhythmogenic PV; (2) use of provocative maneuvers; and (3) the role of circumferential mapping catheters to provide extent, distribution, and activation of PV muscle as well as monitoring distal PV potentials (PVP) during ablation. Radiofrequency ablation can be performed by targeting the PVP during sinus rhythm (right PV) or left atrial pacing (left PV) with the procedural endpoint of PVP elimination, which is more effective in predicting a successful outcome than suppression of acute ectopy. Complete elimination of AF is presently obtained in 70% of patients, allowing interruption of arrhythmias and in use anticoagulants. It is anticipated that continued technologic improvements will improve and facilitate this technique of curative treatment of AF.

Electrophysiological end point for catheter ablation of atrial fibrillation initiated from multiple pulmonary venous foci.

The end point for catheter ablation of pulmonary vein (PV) foci initiating atrial fibrillation (AF) has not been determined. Ninety patients underwent mapping during spontaneous or induced ectopy and/or AF initiation. Ostial PV ablation was performed by use of angiograms to precisely define targeted sites. Success defined by elimination of AF without drugs was correlated with the procedural end point of the abolition of distal PV potentials. A total of 197 arrhythmogenic PV foci (97%)-single in 31% and multiple in 69%-and 6 atrial foci were identified. A discrete radiofrequency (RF) application eliminated the PV potentials in 9 PV foci, whereas 2 foci from the same PV required RF applications at separate sites in 19 cases. In others, a wider region was targeted with progressive elimination of ectopy. In 49 patients, multiple sessions were necessary owing to recurrent or new ectopy. The clinical success rates were 93%, 73%, and 55% in patients with 1, 2, and > or =3 arrhythmogenic PV foci. Recovery of local PV potential and the inability to abolish it were significantly associated with AF recurrences (90% success rate with versus 55% without PV potential abolition). PV stenosis was noted acutely in 5 of 6 cases, remained unchanged at restudy, and was associated with RF power >45 W. Multiple PV foci are involved in initiation of AF, and elimination of PV muscle conduction is associated with clinical success.