Biomedical subjects

Robert Schweikert

Publications and source records attributed to Robert Schweikert.

At least 19 recordsLinked to original sources

PubMed2006

Atrial arrhythmias after surgical maze: findings during catheter ablation.

OBJECTIVES: We describe the clinical and electrophysiologic characteristics and management of post "cut and sew" Maze arrhythmias in symptomatic patients. BACKGROUND: The Cox Maze procedure was developed as a surgical treatment of atrial fibrillation. Until recently, invasive electrophysiologic studies in patients with symptomatic post-operative arrhythmias in this patient population have not been described. METHODS: The management and clinical course of consecutive patients with post-Maze arrhythmias refractory to antiarrhythmic drugs (AADs) between January 2000 and December 2003 are presented. RESULTS: Twenty-three patients (15 men) presented 14 +/- 14 months after Maze surgery for treatment of atrial fibrillation (AF). Eight patients underwent "cut and sew" Maze for lone AF with no other surgical indication. Fifteen patients underwent the "cut and sew" Maze procedure in addition to another surgical procedure: mitral valve surgery (11 patients) and coronary artery bypass graft surgery (4 patients). Eight patients (35%) had recurrent AF secondary to recovered conduction around the lines encircling the pulmonary veins. Five patients were documented to have focal atrial tachycardia, which was mapped to the coronary sinus in 3 patients, to the posterolateral right atrium in 1 patient, and to the left atrial (LA) septum in 1 patient. Four patients had right atrium incisional atrial flutter (AFL), and 6 had LA incisional AFL, which was mapped around the mitral valve annulus in 4 patients and around the right pulmonary veins in 2 patients. Twenty-two of the 23 patients were treated successfully with radiofrequency ablation. At 1-year follow-up, 19 patients were arrhythmia-free and taking no AADs. CONCLUSIONS: After surgical "cut and sew" Maze, approximately one-third of patients experiencing atrial arrhythmias have AF secondary to pulmonary vein-left atrium conduction recovery. Moreover, incisional AFL seems to be a common finding in this group of patients. Catheter-based mapping and ablation of these arrhythmias seems to be feasible and effective.

Aged↗

PubMed2006

Phrenic nerve injury after catheter ablation: should we worry about this complication?

INTRODUCTION: Phrenic nerve injury (PNI) is a complication that can occur with catheter ablation. METHODS: Data from 17 patients with PNI following different catheter ablation techniques were reviewed. PNI was defined as decreased motility (transient) or paralysis (persistent) of the hemi-diaphragm on fluoroscopy or chest X-ray. Patient's recovery was monitored. Normalization of chest images and sniff test would be considered as complete clinical recovery. RESULTS: Out of the 17 PNI patients (16 right, 1 left), 13 (11 persistent, 2 transient) occurred after pulmonary veins isolation with or without superior vena cava ablation. Three patients had persistent PNI after sinus node modification and one other patient experienced PNI after epicardial ventricular tachycardia ablation. Ablation was performed with different energy source including radiofrequency (n = 13), cryothermal (n = 1), ultrasound (n = 2) and laser (n = 1). Patient's symptoms varied broadly from asymptomatic to dyspnea, and even to respiratory insufficiency that required temporary mechanical ventilation support. Two patients with transient PNI resolved immediately after the procedure and the other 15 persistent PNI patients resolved within a mean time of 8.3 +/- 6.6 months. CONCLUSIONS: PNI caused by catheter ablation appears to functionally recover over time regardless of the energy sources used for the procedure.

Adult↗

PubMed2006

Incidence of atrial fibrillation in heart transplant patients: long-term follow-up.

BACKGROUND: The incidence of atrial fibrillation (AF) in heart transplant patients has not been well documented. METHODS: To determine the incidence of AF in a cohort of patients undergoing cardiac transplantation, clinical data were obtained from a prospectively collected database for all consecutive orthotopic heart transplantation (OHT) patients and for all consecutive coronary artery bypass graft (CABG) surgery patients between January 1984 and March 2004 at our institution. A cohort of 1,714 OHT patients and low-risk CABG (normal ejection fraction [EF] and no left ventricular hypertrophy [LVH]) patients were age- and sex-matched. RESULTS: The average age in the two groups was 56 +/- 7 years with 87% male and 81% white race and body mass index (BMI) of 26 +/- 4. There were 3 cases of AF (0.3%) in the OHT group and 757 cases of AF (21%) in the low-risk CABG group. The strongest independent predictor of freedom from postoperative AF was having had a transplant (odds ratio [OR] 96, 95% confidence interval [CI] 13-720). The incidence of AF, atrial flutter (AFL), and supraventricular tachycardia (SVT) in OHT was 0.33, 2.8%, and 1.3%, respectively. Given that incidence of AF, AFL, and SVT in historical post-CABG population is 25%, 17%, and 4.3%, transplanted patients appear to have lower incidence of AF, AFL, and SVT than the reference population. Consistent with this, transplanted patients underwent few ablation procedures for atrial arrhythmias. Additionally, the three patients with AF had bicaval anastomoses suggesting the possibility of PACs originating in the donor superior vena cava (SVC) or IVC (inferior vena cava) initiating AF in these patients. CONCLUSIONS: In a cohort study of transplant and low-risk CABG patients, the strongest independent predictor of freedom from AF is having undergone transplant surgery. One potential explanation for the markedly lower incidence of AF may be effective isolation of thoracic veins with documented cases retaining the native SVC.

Aged↗

PubMed2005

Radiofrequency ablation vs antiarrhythmic drugs as first-line treatment of symptomatic atrial fibrillation: a randomized trial.

CONTEXT: Treatment with antiarrhythmic drugs and anticoagulation is considered first-line therapy in patients with symptomatic atrial fibrillation (AF). Pulmonary vein isolation (PVI) with radiofrequency ablation may cure AF, obviating the need for antiarrhythmic drugs and anticoagulation. OBJECTIVE: To determine whether PVI is feasible as first-line therapy for treating patients with symptomatic AF. DESIGN, SETTING, AND PARTICIPANTS: A multicenter prospective randomized study conducted from December 31, 2001, to July 1, 2002, of 70 patients aged 18 to 75 years who experienced monthly symptomatic AF episodes for at least 3 months and had not been treated with antiarrhythmic drugs. INTERVENTION: Patients were randomized to receive either PVI using radiofrequency ablation (n=33) or antiarrhythmic drug treatment (n=37), with a 1-year follow-up. MAIN OUTCOME MEASURES: Recurrence of AF, hospitalization, and quality of life assessment. RESULTS: Two patients in the antiarrhythmic drug treatment group and 1 patient in the PVI group were lost to follow-up. At the end of 1-year follow-up, 22 (63%) of 35 patients who received antiarrhythmic drugs had at least 1 recurrence of symptomatic AF compared with 4 (13%) of 32 patients who received PVI (P<.001). Hospitalization during 1-year follow-up occurred in 19 (54%) of 35 patients in the antiarrhythmic drug group compared with 3 (9%) of 32 in the PVI group (P<.001). In the antiarrhythmic drug group, the mean (SD) number of AF episodes decreased from 12 (7) to 6 (4), after initiating therapy (P = .01). At 6-month follow-up, the improvement in quality of life of patients in the PVI group was significantly better than the improvement in the antiarrhythmic drug group in 5 subclasses of the Short-Form 36 health survey. There were no thromboembolic events in either group. Asymptomatic mild or moderate pulmonary vein stenosis was documented in 2 (6%) of 32 patients in the PVI group. CONCLUSION: Pulmonary vein isolation appears to be a feasible first-line approach for treating patients with symptomatic AF. Larger studies are needed to confirm its safety and efficacy.

Anti-Arrhythmia Agents↗

PubMed2005

Safety and efficacy of radiofrequency energy catheter ablation of atrial fibrillation in patients with pacemakers and implantable cardiac defibrillators.

BACKGROUND: Catheter ablation has significantly transformed the clinical management of atrial fibrillation (AF). The safety and efficacy of this procedure are not well understood in patients with pacemakers and defibrillators. OBJECTIVES: The purpose of this study was to study the impact of radiofrequency catheter ablation of AF in patients with pacemakers and implantable cardiac defibrillators. METHODS: We studied 86 patients with pacemakers and defibrillators (group I) and a similar number of age- and gender-matched controls (group II) who underwent AF ablation between 1999 and 2004. Clinical and procedural variables were compared between the two groups. In group I, various generator and lead parameters were compared before and after the procedure. Resurgence of clinical AF after 2 months was considered recurrence. RESULTS: Both groups were similar with regard to age, gender, body mass index, and type of AF. Group I had a higher incidence of diabetes (17% vs 6%, P = .03), coronary artery disease (25% vs 13%, P = .05), less prolonged AF (31 +/- 21 vs 45 +/- 30 months, P <.001), lower left ventricular ejection fraction (49 +/- 13% vs 52 +/- 9%, P = .03), and left ventricular end-diastolic dimensions (4.97 +/- 0.81 vs 4.72 +/- 0.67, P = .03). No changes in the sensing and pacing thresholds, impedance of atrial and ventricular leads, or defibrillator coil impedance after AF ablation were observed in group I. Atrial lead dislodgment was seen in two patients. Transient abnormal but "expected" pulse generator behavior was seen in 25% of patients without permanent malfunction. Stroke (1% vs 1%, P = 1.000), pulmonary vein stenosis (2% vs 1%, P = .77), and AF recurrence rates at 12 months were similar between groups I and II, respectively (19% vs 21%, P = .73). CONCLUSION: AF ablation is safe and efficacious in patients with pacemakers and defibrillators.

Atrial Fibrillation↗

PubMed2005

Response to pharmacological challenge of dissociated pulmonary vein rhythm.

UNLABELLED: Dissociated pulmonary vein rhythm. INTRODUCTION: Characterization of the electrophysiologic behavior of the pulmonary vein (PV) triggers initiating atrial fibrillation (AF) is still lacking. We conducted the current study to evaluate the behavior of the dissociated PV rhythm (PVD) observed after electrical disconnection from the left atrium of the PV responsible for initiation of AF. METHODS AND RESULTS: Four hundred and seven consecutive patients (102 women; mean age 55+/-11 years) presented for ablation of symptomatic AF to our laboratory. After isolation, sustained dissociated rhythm (>10 minutes) was documented in 2.1% (34 of 1,568 PVs) of the PVs (initiating AF prior to isolation). Adenosine (18 mg IV bolus), verapamil (10 mg IV bolus), phenylephrine (200 mcg bolus followed by infusion at 100 mcg/hour), and isoproterenol (infusion rate of 15 mcg/hour) were administered in these patients. The cycle length of the PV rhythm before and after the administration of drugs was measured. Adenosine prolonged the sinus node (SN) cycle length (from 750+/-105 to 1,900+/-200 ms; P<0.05) and suppressed the PVD. Isoproterenol shortened both the SN (from 750+/-105 to 420+/-150 ms; P<0.05) and the PVD (from 2,225+/-300 to 800+/-190 ms; P<0.05) cycle length. A similar response to adenosine and isoproterenol of the PV firing was observed prior to isolating the arrhythmogenic PV. Phenylephrine prolonged the cycle length of both the SN (from 740+/-115 to 960+/-90 ms; P<0.05) and the PV rhythm (from 2,200+/-300 to 2,355+/-280 ms; P=0.87). Verapamil did not cause a significant change either in the SN or in the PVD cycle length. CONCLUSION: Our data suggest that the PVD within isolated PV responsible for initiating AF exhibits a response to pharmacologic agents similar to the SN cells.

Adenosine↗

PubMed2005

Left atrial flutter following pulmonary vein antrum isolation with radiofrequency energy: linear lesions or repeat isolation.

INTRODUCTION: Left atrial flutter (LAFL) is a known complication of pulmonary vein isolation. Treatment of this arrhythmia currently involves both linear lesions as well as re-isolation. However, it is unknown if re-isolation alone is sufficient to prevent recurrence. This study reviews the incidence of LAFL following segmental PV antrum isolation (PVAI) in a large patient population and evaluates if re-isolation alone is sufficient to prevent recurrence. METHODS AND RESULTS: Seven hundred thirty-seven patients underwent PVAI. Twenty-three patients (3.1%) developed post-PVAI LAFL. All patients underwent a second procedure in which only repeat PVAI was done. During the second procedure, all flutter circuits were electroanatomically mapped. All patients were followed at 3, 6, and 12 months. All 23 patients demonstrated recovery in one or more PV. After repeat isolation of the PVs, 61% of patients were arrhythmia free off all antiarrhythmic drugs. A relationship between the presence/absence of pre-existing left atrial (LA) scar was observed. Of the 11 patients with pre-existing LA scar, 36% remained arrhythmia free off antiarrhythmic drugs. In contrast, of the 12 patients without pre-existing LA scar, 83% remained arrhythmia free off antiarrhythmic drugs (P = 0.03). CONCLUSION: Among patients with LAFL following PVAI, re-isolation alone is sufficient in preventing recurrence in patients without pre-existing LA scar. Patients with pre-existing LA scar tend to have recurrence requiring further ablation including linear lesions, and continue to need antiarrhythmic medications.

Atrial Fibrillation↗

PubMed2005

The impact of povidone-iodine pocket irrigation use on pacemaker and defibrillator infections.

BACKGROUND: Infection is a devastating complication of permanent pacemakers (PMs) implantable cardioverter defibrillators (ICDs). Many implanting physicians commonly use povidone-iodine solution to irrigate the device pocket before implanting the device. We sought to assess if such a measure would alter the rate of infection. METHODS: A total of 2,564 consecutive patients who received implantable PM or ICD devices between 1994 and 2002 were studied. Povidone-iodine was used for pocket irrigation in 53% and saline in 47%. A total of 18 (0.7%) patients developed pocket infections with 0.7% (10/1,359) in povidone-iodine (group I) and 0.6% (8/1,205) in saline (group II) pocket irrigation (p = ns). Groups I and II were studied for various clinical and demographic variables described in the results section. RESULTS: There was no statistical difference in the baseline demographic and clinical characteristics between groups I and II, respectively. ICDs were most frequently infected than PMs (56% vs 44%). Most (83%) of the devices were dual chamber. Reopening of the pocket for either lead or generator replacement had a higher incidence of infection than new implants (61% vs 39%). There was no difference in the use of preimplantation antibiotic prophylaxis. Late (61%) and deep pocket infections (78%) were more common than early (39%) and superficial infections (22%). Blood cultures were positive in 67% and Staphylococcus aureus was the common most pathogen (50%). The mean duration of antibiotics use after the diagnosis of device infection was 35 +/- 23 days with 72% requiring device explantation. The device was reimplanted on the contralateral side in 56% cases. One patient in each group died due to device infection and related complications. No significant allergy to iodine was seen in either group. CONCLUSION: Povidone-iodine irrigation of the subcutaneous pocket did not alter the rates of pocket infection after pacemaker/defibrillator implantation.

Aged↗

PubMed2005

The role of swab and tissue culture in the diagnosis of implantable cardiac device infection.

BACKGROUND: The isolation of a pathogen is vital in the diagnosis and treatment of a device infection. A swab culture, despite poor sensitivity, is the most common method used in specimen collection. OBJECTIVE: To determine the relative value of swab and tissue specimen cultures in patients with implantable cardiac pacemakers and defibrillators. DESIGN: Prospective patient cohort study. SETTING: A 1,000-bed tertiary referral center in Cleveland, Ohio. PATIENTS: Consecutive patients with implantable cardiac pacemaker or defibrillator presenting for lead extraction from October 1, 2000 to March 31, 2001. METHODS: Tissue and swab cultures were prospectively collected during pacemaker and implantable defibrillator surgeries that required lead extraction. Clinical manifestations, microbiology, and echocardiographic data were recorded in patients with and without a clinical diagnosis of device system infection. RESULTS: Seventy-one patients with implantable pacemaker (n = 49, 69%), implantable defibrillator (n = 18, 25%), or both devices (n = 4, 6%) requiring lead extraction had pocket swab and tissue cultures for analysis. Infection was evident clinically in 35 (49%) of the patients and absent in the remainder. The most common bacteria isolated were coagulase-negative Staphylococcus (37%) and Staphylococcus aureus (10%). Patients with clinical infection had positive cultures more frequently (P = 0.002) by pocket tissue culture (n = 24, 69%) than by swab culture (n = 11, 31%). However, patients without clinical infections had positive cultures at similar rates by pocket tissue culture (n = 10, 28%) and by swab culture (n = 8, 22%; P = 0.48). Patients without clinical infection were not treated with other than perioperative antibiotics, and did not develop clinical infections. CONCLUSION: Pocket tissue cultures are more effective than pocket swab cultures for the isolation and identification of the infectious pathogens in cardiac device infections. Positive cultures by pocket swab or tissue cultures in the absence of clinical signs and symptoms of infection does not imply infection or the need for specific therapy.

Aged↗

PubMed2004

Mode of initiation and ablation of ventricular fibrillation storms in patients with ischemic cardiomyopathy.

OBJECTIVES: We report on the initiation of ventricular fibrillation (VF) storm in patients with ischemic cardiomyopathy (ICM) and the results of targeted ablation to treat VF storm. BACKGROUND: Monomorphic premature ventricular contractions (PVCs) have been shown to initiate VF in patients without structural heart disease. METHODS: A total of 29 patients with ICM and documented VF initiation were identified. In 21 patients, VF storm was controlled with antiarrhythmic drugs and/or treatment of heart failure. Eight patients with VF (mean 52 +/- 25 episodes) refractory to medical management required ablation. All patients underwent three-dimensional electroanatomical mapping using CARTO (Biosense-Webster Inc., Diamond Bar, California), and PVCs were mapped when present. Scarred areas were identified using voltage mapping. RESULTS: Monomorphic PVCs initiated VF in all 29 identified patients. Five of eight patients requiring ablation had frequent PVCs that allowed PVC mapping. The earliest activation site was consistently located in the scar border zone. The PVCs were always preceded by a Purkinje-like potential (PLP). Ablation was successfully performed at these sites. In three patients, infrequent PVCs prevented mapping, but PLPs were recorded around the scar border. Ablation targeting these potentials along the scar border was successfully performed. During follow-up (10 +/- 6 months), one patient had a single VF episode and another developed sustained, monomorphic ventricular tachycardia. There was no recurrence of VF storm. CONCLUSIONS: Ventricular fibrillation in ICM is triggered by monomorphic PVCs originating from the scar border zone with preceding PLPs; targeting these PVCs may prevent VF recurrence. In the absence of PVCs, both substrate mapping and ablation appear to be equally effective.

Aged↗

PubMed2004

Pulmonary vein isolation for the treatment of atrial fibrillation in patients with impaired systolic function.

OBJECTIVES: We aimed to determine the safety and efficacy of pulmonary vein isolation (PVI) in atrial fibrillation (AF) patients with impaired left ventricular (LV) systolic function. BACKGROUND: To date, PVI has been performed primarily in patients with normal LV function. Yet, many AF patients have impaired LV systolic function. The outcomes of PVI in patients with impaired LV systolic function are unknown. METHODS: We included 377 consecutive patients undergoing PVI between December 2000 and January 2003. Ninety-four patients had impaired LV function (ejection fraction [EF] <40%), and they comprised the study group. The control group was the remaining 283 patients who had a normal EF. End points included AF recurrence and changes in EF and quality of life (QoL). RESULTS: Mean EF was 36% in our study group, compared with 54% in controls. After initial PVI, 73% of patients with impaired EF and 87% of patients with normal EF were free of AF recurrence at 14 +/- 6 months (p = 0.03). In the study group, there was a nonsignificant increase in EF of 4.6% and significant improvement in QoL. Complication rates were low and included a 1% risk of pulmonary vein stenosis. CONCLUSIONS: Although the AF recurrence rate after initial PVI in impaired EF patients was higher than in normal EF subjects, nearly three-fourths of patients with impaired EF remained AF-free. Although our sample size was nonrandomized, our results suggest PVI may be a feasible therapeutic option in AF patients with impaired EF. Randomized studies with more patients and longer follow-up are warranted.

Atrial Fibrillation↗

PubMed2004

Pulmonary vein antrum isolation for treatment of atrial fibrillation in patients with valvular heart disease or prior open heart surgery.

OBJECTIVES: The goal of this study was to assess the safety and efficacy of pulmonary vein antrum isolation in patients with moderate valvular heart disease or open-heart surgery and atrial fibrillation (AF). BACKGROUND: Valvular heart disease and open-heart surgery are commonly associated with AF and increase the risk of adverse events in AF patients. METHODS: A total of 391 consecutive patients who had pulmonary vein antrum isolation performed between December 2000 and December 2002 were screened. A total of 142 of these patients had clinically significant valvular disease or prior cardiac surgery. End points included AF recurrence and pulmonary vein antrum isolation complication rates. RESULTS: Patients with valvular heart disease or prior open-heart surgery were older, had larger left atria and a more advanced New York Heart Association class. They did not differ significantly with respect to gender, but had a longer history of AF. Procedure times were similar between patients with and without valvular heart disease or prior open-heart surgery. After 18 +/- 7 months in the lone AF patients, 11 +/- 5 months in patients with valvular heart disease, and 10 +/- 5 months in patients with prior open heart surgery, there was a trend toward lower recurrence of AF in patients with lone AF who enjoyed a 98% overall cure rate after up to 2 pulmonary vein antrum isolations versus 93% among patients with valvular heart disease (P = .04) and prior open heart surgery (P = .07). Complication rates were comparable between groups. CONCLUSIONS: Pulmonary vein antrum isolation is safe and effective in patients with moderate valvular heart disease and the patients who developed AF after open-heart surgery. These results have implications for our understanding of the pathophysiology of AF in patients with moderate valvular heart disease or past cardiac surgery and should be considered when discussing treatment options in these patients.

Atrial Fibrillation↗

PubMed2004

Pulmonary vein isolation for atrial fibrillation in patients with symptomatic sinus bradycardia or pauses.

INTRODUCTION: Sick sinus syndrome is commonly associated with tachyarrhythmias and bradyarrhythmias that often are symptomatic. The aim of this study was to assess the effect of pulmonary vein isolation in patients with sick sinus syndrome and atrial fibrillation (AF). METHODS AND RESULTS: Three hundred fourteen consecutive patients who underwent pulmonary vein isolation between December 2000 and January 2002 were included in the study. Thirty-one patients had sick sinus syndrome, which was defined as a preprocedural history of symptomatic sinus bradycardia or pauses. Endpoints included AF recurrence, change in the frequency of sinus pauses, and symptoms of presyncope or syncope, as well as mean heart rate and percentage of atrial pacing in patients with pacemakers implanted prior to the pulmonary vein isolation. Patients had AF for an average of 6 +/- 3 years. Patients were 58 +/-8 years old and had ejection fractions of 55 +/- 4%. Sixty-one percent had implanted pacemakers. AF recurred within 6 months in 4 patients. Two had a successful second pulmonary vein isolation procedure. There were no recurrences of presyncopal events (P < 0.05) or documented sinus pauses (P < 0.05) after successful pulmonary vein isolation in the patients without permanent pacemakers. Patients with pacemakers had a 13-fold reduction in the percentage of atrial pacing (P < 0.05). Both groups showed a significant increase in average heart rates at 6-month follow-up. CONCLUSION: Cure of AF by pulmonary vein isolation helped resolve the clinical manifestations of sick sinus syndrome, suggesting that the occurrence of AF and/or the associated treatment could be partially responsible for sick sinus syndrome.

Analysis of Variance↗

PubMed2003

Randomized study comparing combined pulmonary vein-left atrial junction disconnection and cavotricuspid isthmus ablation versus pulmonary vein-left atrial junction disconnection alone in patients presenting with typical atrial flutter and atrial fibrillation.

BACKGROUND: Atrial flutter (AFL) and atrial fibrillation (AF) frequently coexist in the same patient. Recently it has been demonstrated that the triggers for both AF and AFL may originate in the pulmonary veins (PVs). We hypothesized that in patients with both AF and typical AFL, pulmonary vein-left atrial junction (PV-LAJ) disconnection may eliminate both arrhythmias. METHODS AND RESULTS: Consecutive patients with documented symptomatic AF and typical AFL were randomly assigned to have PV-LAJ disconnection combined with cavotricuspid isthmus (CTI) ablation (group 1, n=49) or PV-LAJ disconnection alone (group 2, n=59). Within the first 8 weeks after ablation, 32 of the group 2 patients had typical AFL documented, whereas none was seen in group 1. Twenty of these 32 converted to sinus rhythm after initiating antiarrhythmic drugs (AADs). Twelve were cardioverted, and AADs were started. After 8 weeks, all AADS were stopped, and only 3 patients continued to have recurrent sustained typical AFL that was eliminated by CTI ablation. Beyond 8 weeks of follow-up, 7 patients in group 1 and 6 patients in group 2 (14% and 11%, respectively) continued to have AF. Ten of these 13 patients underwent a repeat PV-LAJ disconnection procedure and were cured. The remaining 3 remained in normal sinus rhythm while taking AADs. CONCLUSIONS: In patients with both AFL and AF, PV-LAJ disconnection alone may be sufficient to control both arrhythmias. CTI block reduced early postablation recurrence of arrhythmias, which in the majority of patients reflects a short-term clinical problem.

Anti-Arrhythmia Agents↗

PubMed2003

Phased-array intracardiac echocardiography monitoring during pulmonary vein isolation in patients with atrial fibrillation: impact on outcome and complications.

BACKGROUND: The objective of this study was to assess the impact of intracardiac echocardiography (ICE) on the long-term success and complications in patients undergoing pulmonary vein isolation (PVI) for treatment of atrial fibrillation (AF). METHODS AND RESULTS: Three hundred fifteen patients underwent PVI for treatment of AF. Each patient underwent ostial isolation of all PVs using a cooled-tip ablation catheter. PVI was performed using circular mapping (CM) alone (group 1, 56 patients), CM and ICE (group 2, 107 patients), and CM and ICE with titration of radiofrequency energy based on visualization of microbubbles by ICE (group 3, 152 patients). After a mean follow-up time of 417+/-145 days, 19.6% (11 of 56), 16.8% (18 of 107), and 9.8% (15 of 152) of patients in groups 1, 2, and 3 experienced recurrence of AF, respectively. Moreover, whereas no group 3 patient experienced severe (>70%) PV stenosis, severe PV stenosis was documented in 3 (3.5%) of 56 patients in group 1 and in 2 (1.8%) of 107 patients in group 2 (P<0.05). No embolic events were detected in group 3 patients. CONCLUSIONS: Intracardiac echocardiography improves the outcome of cooled-tip PVI. Power adjustment guided by direct visualization of microbubble formation reduces the risk of PV stenosis and improves long-term cure.

Atrial Fibrillation↗

PubMed2003

Use of different catheter ablation technologies for treatment of typical atrial flutter: acute results and long-term follow-up.

OBJECTIVES: We report the acute success and long-term follow-up in consecutive patients undergoing catheter ablation of typical right atrial flutter (AFL) using different ablation technologies. METHODS: One hundred and two patients presenting for treatment of AFL to our laboratory were included in the study. Based on availability and physician preference, ablation was performed with either a cooled-tip catheter (39 patients, group I), an 8- or 10-mm tip catheter connected to a high-power radiofrequency (RF) generator (25 patients, group II), or a 4- or 5-mm tip catheter (38 patients, group III). Acute ablation success was achieved in all group II and group III patients. Among the 38 patients undergoing ablation with the conventional catheter tip (group I), crossover to an 8-mm tip or a cooled tip ablation catheter was required in 11 patients (29%). The mean fluoroscopy time was significantly higher in group I (54.3 +/- 26.4 minutes) when compared to group II (39.6 +/- 19.6 minutes; P < 0.05) and group III (40 +/- 16 minutes; P = 0.0.5). After a mean follow up of 20 +/- 5 months no patient in group II experienced recurrence of AFL, whereas 18.4% (7 of 38 patients; P < 0.05) in group I and 10% (4 of 39 patients; P < 0.05) in group III had recurrence of AFL. Ablation technologies designed to obtain larger size lesions appeared to be more effective in achieving acute ablation success of AFL and in limiting the long-term recurrence rate of this arrhythmia.

Atrial Flutter↗

PubMed2003

Three-dimensional reconstruction of pulmonary veins in patients with atrial fibrillation and controls: morphological characteristics of different veins.

Multidetector computed tomography can be used to evaluate the anatomy of pulmonary veins (PVs) in patients with AF. The study evaluated two groups. Group 1 included 61 patients assessed following PV ablation with ultrasound of RF energy. Group 2 included 15 patients undergoing ablation for AF and 14 control subjects without a history of AF matched for age and sex. The anatomy of the PVs was analyzed in this group prior to the ablation and compared to controls. Computed tomography was used to measure the ostium of the left superior, left inferior, right superior, right inferior PVs, and the left atrial appendage size. In group 1, PV stenosis was seen in 14 (30%) of 46 patients undergoing ablation with RF energy and in none of the 15 patients receiving ablation with ultrasound energy. In group 2, the ostium size was not different between patients with AF and controls. Similarly, the ostium of the PV that appeared to trigger AF was not larger than the ostium of the remaining veins. A "clustering pattern" of PV branches near the right inferior PV ostium was seen in almost every patient, independent of the presence of the arrhythmia. Computed tomography frequently detects PV stenosis following RF ablation. Ultrasound ablation does not appear to result in PV narrowing. Overall, patients with AF do not have larger sizes of PV ostia. Multiple ramifications from the right inferior PV ostium is a common pattern and may represent a protective anatomic variant.

Atrial Fibrillation↗

PubMed2002

Circular mapping and ablation of the pulmonary vein for treatment of atrial fibrillation: impact of different catheter technologies.

OBJECTIVES: We conducted this study to compare the efficacy and safety of different catheter ablation technologies and of distal versus ostial pulmonary veins (PV) isolation using the circular mapping technique. BACKGROUND: Electrical isolation of the PVs in patients with atrial fibrillation (AF) remains a technical challenge. METHODS: Two hundred eleven patients (163 men; mean age 53 +/- 11 years) with symptomatic AF were included in this study. In the first 21 patients (group 1), distal isolation (> or = 5 mm from the ostium) was achieved targeting veins triggering AF. In the remaining 190 patients (group 2), ostial isolation of all PVs was performed using 4-mm tip (47 patients), 8-mm tip (21 patients), or cooled-tip (122 patients) ablation catheters. RESULTS: Distal isolation was able to eliminate premature atrial contractions (PACs) and AF in six of 21 patients (29%) and 10 of 34 PVs. After a mean follow-up time of 6 +/- 4 months, no patients treated with the 8-mm tip catheter experienced recurrence of AF, whereas 21% (10 of 47 patients) and 15% (18 of 122 patients) of the patients ablated with the 4-mm tip and the cooled-tip ablation catheters experienced recurrence of AF after a mean follow-up of 10 +/- 3 and 4 +/- 2 months, respectively. Significant complications including stroke, tamponade, and severe stenosis occurred in 3.5% (8/211) of patients. CONCLUSIONS: Catheter technologies designed to achieve better lesion size appeared to have a positive impact on procedure time, fluoroscopy time, number of lesions, and overall efficacy. Although distal isolation can be achieved with fewer lesions, ostial isolation is required in the majority of patients to eliminate arrhythmogenic PACs and AF.

Adult↗