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Sanjeev Saksena

Publications and source records attributed to Sanjeev Saksena.

At least 19 recordsLinked to original sources
PubMed2005

Intra-cardiac echocardiography guided cardioversion to help interventional procedures (ICE-CHIP) study: study design and methods.

The ICE CHIP study is a sequential Phase I and Phase II pilot study comparing the cardiac imaging capabilities of intracardiac echocardiography (ICE) with with transesophageal echocardiography (TEE) followed by a randomized comparison of ICE guided cardioversion with a conventional cardioversion strategy in patients with atrial fibrillation. It is a prospective open label randomized multi-center investigation performed in two phases designed to initially compare two distinct imaging modalities (Phase 1) and subsequently two different strategies (ICE guided Cardioversion and Conventional) in the management of AF in patients undergoing invasive cardiac procedures in whom electrical cardioversion is indicated (Phase 2). This study will examines two hypotheses in AF patients undergoing invasive cardiac procedures: (1) ICE has comparable efficacy to TEE in visualization of left atrial pathology including thrombi or interatrial septal defects. This will be evaluated during the Phase I component of the study. (2) ICE can identify low risk patients in whom immediate cardioversion during the procedure is safe and comparably effective to electrical cardioversion performed based on a conventional strategy of a minimum of 3 weeks of preceding anticoagulation therapy. Phase 1 will enroll 100 patients at 12 centers, who will undergo a clinically indicated TEE procedure and cardiac catheterization procedure. Each patient will be imaged by TEE & ICE and a core echo laboratory will perform a blinded comparison of the two imaging modalities. In Phase 2, a total of 300 patients (3:2 randomization) will be enrolled in the study at up to 15 investigational sites in USA and Europe. The composite incidence rate of major cardiac and bleeding complications (stroke, TIA, peripheral embolism, major hemorrhagic event) will be compared between the two treatment groups over the duration of the study.

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PubMed2005

Implantable defibrillators configured for hybrid therapy of persistent and permanent atrial fibrillation: initial clinical experience with a novel lead system.

AIM: Hybrid therapy strategies have combined antiarrhythmic drugs (AAD) with pacemakers, atrio-ventricular defibrillators (AV ICD) or atrial ablation individually. The feasibility combining AAD with dual site RA pacing (DAP) in an AV ICD has not been examined. METHODS: We used an AV ICD with a novel lead configuration permitting DAP, antitachycardia pacing (ATP) or atrial shocks (ADF) in patients (pts) with refractory persistent or permanent AF. Hybrid therapy included linear RA ablation and/or focal ablation. Continuous DAP and automatic ATP with patient or physician activated ADF. RESULTS: 24 pts, mean age 66 +/- 10 yrs, with cardiac disease (22 pts), underwent insertion of an AVICD with dual RA leads. 20 patients had concomitant ablative procedures (RA only = 19, RA + LA = 1) and all pts continued previously ineffective AAD. During a follow-up of 2-36 months (mean 17 +/- 8 mos), rhythm control was restored in all pts & maintained long-term in 19 (83%) pts. 8 pts used AF termination therapies successfully. Device datalogs showed no episodes of AF in 6 pts, asymptomatic brief arrhythmias in 4 pts, infrequent paroxysmal AF in 9 pts & persistent AF recurred in 5 pts. AV ICD detection algorithms reliably detected AF or AT in the DAP mode in all pts. Intermittent brief P wave double counting occurred during AT in selected pts. No pt received inappropriate ADF therapy. CONCLUSIONS: 1. DAP can be safely incorporated in an AVICD devices for use in an hybrid therapy strategy for AF pts. 2. These devices can be effective for both AF prevention & termination. 3. Long term rhythm control can be achieved and documented by device datalogs in persistent and permanent AF.

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PubMed2005

Dual site right atrial pacing can improve the impact of standard dual chamber pacing on atrial and ventricular mechanical function in patients with symptomatic atrial fibrillation: further observations from the dual site atrial pacing for prevention of atrial fibrillation trial.

BACKGROUND: The effects of atrial pacing mode on atrial and ventricular function in patients with atrial fibrillation (AF) and bradycardia have not been evaluated. We evaluated atrial and ventricular function during randomization to support pacing (SP), high right atrial pacing (HRA), and dual site right atrial pacing (DAP). METHODS: Seventy-nine patients (66 +/- 12 yr, 46 male) with standard pacing indications and symptomatic AF were randomized to each of three pacing modes (DAP, HRA, SP) for 6 months in a crossover design. Echocardiographic studies were performed at enrollment and the end of each mode. Paired comparisons of atrial and ventricular function parameters were performed between each pacing mode and baseline. RESULTS: HRA pacing in DDDR mode resulted in increased left ventricular (LV) end systolic volume (78 +/- 42 vs. 60 +/- 31 ml, p = 0.001) and reduced LV ejection fraction (44 +/- 14 vs. 50 +/- 11%, p = 0.007) compared to baseline. These parameters did not change during DAP. DAP resulted in increased peak A wave velocity (75 +/- 19 vs. 63 +/- 23 cm/s, p = 0.003) and atrial filling fraction compared to baseline (0.47 +/- 0.15 vs. 0.38 +/- 0.13, p = 0.005). Atrial and ventricular function were similar between control and SP. CONCLUSION: DAP, but not HRA or SP, improved left atrial (LA) function in patients with AF and bradycardia. HRA pacing in DDDR mode resulted in LA dilatation and deterioration of LV function which was not observed with DAP.

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PubMed2005

Relationship between atrial tachyarrhythmias and symptoms.

OBJECTIVES: The purpose of this study was to correlate patient-reported symptoms of atrial fibrillation with the underlying rhythm. BACKGROUND: The reliability of patient-reported symptoms as a marker of atrial fibrillation recurrence has not been well studied. METHODS: This prospective multicenter trial correlated the recurrence of atrial tachyarrhythmias with symptoms in patients with a history of atrial fibrillation and a standard indication for permanent pacing. Pacemaker-detected atrial tachyarrhythmia events were correlated with symptoms. Patients logged symptomatic events into the device's memory via an external manual activator. Patients were followed for 12 months and were contacted weekly to ensure compliance with activator usage. Episodes were classified as symptomatic atrial tachyarrhythmia, asymptomatic atrial tachyarrhythmia, or symptomatic nonatrial tachyarrhythmia depending on concordance between patient symptoms and the rhythm. RESULTS: Forty-eight patients underwent implantation of a DDDRP pacemaker and were followed for 12 +/- 2 months. A median of 25.0 (4.0-55.8) symptomatic events attributed to atrial fibrillation. A median of 1.0 (0.0-10.0) symptomatic atrial tachyarrhythmia episodes were documented during follow-up. Symptoms related to atrial fibrillation were reported in 6% of atrial tachyarrhythmia episodes identified by the pacemaker. The probability that symptoms were associated with an atrial tachyarrhythmia (positive predictive value) was 17%. The ventricular rate between symptomatic and asymptomatic atrial tachyarrhythmia events was not significantly different. CONCLUSIONS: Among patients with symptomatic bradycardia and a history of atrial fibrillation, symptoms of atrial fibrillation often were not associated with documented atrial tachyarrhythmias, and more than 90% of atrial tachyarrhythmias were clinically silent.

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PubMed2005

Biatrial and three-dimensional mapping of spontaneous atrial arrhythmias in patients with refractory atrial fibrillation.

INTRODUCTION: While atrial fibrillation (AF) initiation in the pulmonary veins has been well-studied, simultaneous biatrial and three-dimensional noncontact mapping (NCM) has not been performed. We hypothesized that these two techniques would provide novel information on triggers, initiation, and evolution of spontaneous AF and permit study of different AF populations. METHODS AND RESULTS: The origin of atrial premature beats (APBs), onset of spontaneous AF and its evolution were analyzed in 50 patients with AF in the presence or absence of structural heart disease (SHD) and in different AF presentations (group A: Persistent, group B: Paroxysmal). In 45 patients, spontaneous APBs in the right atrium (RA; n = 60) and left atrium (LA; n = 25) with similar regional distributions regardless of heart disease status were demonstrated. In total, 22 patients (44%) had > or =2 disparate regional origins. Biatrial regional foci were seen with equal frequency in patients with SHD (31%), without SHD (40%), in group A (32%), and in group B (36%). Biatrial mapping and NCM showed organized monomorphic atrial tachyarrhythmias arising in the RA (17), septum (17), or LA (21) and were classified as atrial flutter (RA = 34, LA = 8), macro-reentrant atrial tachycardia (RA = 1, LA = 3) or focal atrial tachycardia (RA = 2, LA = 7). Their regional distribution was more extensive in patients with SHD and persistent AF compared with patients without SHD or paroxysmal AF. Simultaneous biatrial tachycardias were observed only in group A patients and those with SHD. CONCLUSIONS: Simultaneous biatrial and NCM permits successful AF mapping in different AF populations and demonstrates a biatrial spectrum of spontaneous triggers and tachycardias. Organized monomorphic tachycardias with multiple unilateral or biatrial locations are commonly observed in human AF. Patients with heart disease or persistent AF have a more extensive distribution as well as simultaneous coexistence of multiple tachycardias during AF.

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PubMed2004

Long-term rhythm control of drug-refractory atrial fibrillation with "hybrid therapy" incorporating dual-site right atrial pacing, antiarrhythmic drugs, and right atrial ablation.

We evaluated the long-term efficacy, safety, and applicability of a "hybrid" therapy strategy for rhythm control in atrial fibrillation (AF), incorporating dual-site right atrial pacing, antiarrhythmic drugs, and right atrial ablation. One hundred thirteen patients (paroxysmal AF [n = 70], persistent/permanent AF [n = 43]) with refractory symptomatic AF were treated with this strategy and followed for 1 to 81 months (mean 30 +/- 23). All-cause mortality, AF recurrences, and progression to permanent AF were monitored and recorded by implanted device data logs. There was no procedural mortality. Rhythm control was achieved in 90% of all patients at 3 and 5 years, with comparable efficacy in subpopulations with paroxysmal (98%), persistent, or permanent AF (87%, p >2). Overall survival was 84% at 3 years and 80% at 5 years, and was higher in patients with paroxysmal AF than in patients with persistent or permanent AF (86% vs 67% at 4 years, p <0.001). Patients with persistent or permanent AF had a greater need for cardioversion (p <0.004) and right atrial ablation (p <0.04) than patients with paroxysmal AF to achieve comparable rhythm control. A hybrid therapy strategy can provide safe and effective long-term rhythm control in patients with drug-refractory AF, and can be implemented in subpopulations presenting with paroxysmal, persistent, or permanent AF.

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PubMed2003

Effectiveness of rhythm control in persistent or permanent atrial fibrillation with overdrive atrial pacing and antiarrhythmic drugs after linear right atrial catheter ablation.

Right atrial (RA) maze procedures using linear catheter ablation have had limited efficacy in paroxysmal atrial fibrillation (AF). We hypothesized that "hybrid" therapy using overdrive atrial pacing and antiarrhythmic drugs can improve efficacy of catheter RA maze and expand its role to persistent or permanent AF. Catheter RA maze procedures were performed in 26 patients with persistent or permanent AF refractory to 4.5 +/- 2.1 antiarrhythmic drugs. Overdrive dual-site RA pacing (21 patients) or high RA pacing (5 patients) was continued (n = 11) or instituted periablation (n = 15). All patients continued receiving previously ineffective antiarrhythmic drugs. Freedom from permanent AF (rhythm control), symptomatic and/or asymptomatic AF recurrences, the safety of hybrid therapy, and overall survival were assessed. There was no procedure-related mortality or stroke. Rhythm control was achieved in 24 patients (92%) within 3 months. During long-term follow-up (6 to 49 months, mean 17 +/- 10), rhythm control was maintained in 20 patients (77%). Nine patients (35%) had no AF recurrences, whereas 11 patients maintained rhythm control with infrequent AF recurrences. Device datalogs at the study cut-off point demonstrated no AF events in 6 patients, nonsustained atrial tachycardia in 2 patients, and brief asymptomatic paroxysmal AF in 12 patients. Actuarial patient survival was 95% at 1 year and 74% at 2 years of follow-up. Thus, hybrid therapy utilizing catheter RA maze procedures with overdrive atrial pacing and antiarrhythmic drugs can be performed safely and can reestablish rhythm control in selected patients with refractory persistent or permanent AF.

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