Biomedical subjects

Steven P Kutalek

Publications and source records attributed to Steven P Kutalek.

10 recordsLinked to original sources

PubMed2006

Decremental ramp atrial extrastimuli pacing protocol for the induction of atrioventricular nodal re-entrant tachycardia and other supraventricular tachycardias.

AIM: The primary aim of this study was to evaluate the utility of decremental ramp atrial extrastimuli pacing protocol (PRTCL) for induction of atrioventricular nodal re-entrant tachycardia (AVNRT), and other supraventricular tachycardias (SVTs), compared to standard (STD) methods. METHODS: The study cohort of 121 patients (age 57.51 +/- 14.02 years) who presented with documented SVTs and/or symptoms of palpitations and dizziness, and underwent invasive electrophysiological evaluation was divided into Group I (AVNRT, n = 42) and Group II (Control, n = 79). The PRTCL involved a train of six atrial extrastimuli, delivered in a decremental ramp fashion. The STD methods included continuous burst and rapid incremental pacing up to atrioventricular (AV) block cycle length, and single and occasionally double atrial extrastimuli. Prolongation in the Atrio-Hisian (Delta-AH) intervals achieved by both methods were compared, as were induction frequencies. RESULTS: In Group I, three categories of responses--(1) induction of AVNRT, (2) induction of echo beats only, and (3) none--were observed in 29 (69%), 11 (26%), and 2 (5%) patients with the PRTCL, when compared with 14 (33%), 16 (38%), and 12 (29%) patients with STD methods in the baseline state without the use of pharmacological agents. The Delta-AH intervals for each of these three categories were larger using PRTCL versus STD methods; 293.3 +/- 95.2 ms versus 192.9 +/- 61.4 ms (P < 0.005), 308.6 +/- 68.5 ms versus 189. 9 +/- 64.9 ms (P < 0.0005), and 203.0 +/- 86.3 ms versus 145.8 +/- 58.9 ms (P = NS), respectively. In Group II, in one patient with dual AV nodal physiology but no clinical tachycardia, the PRTCL induced nonsustained (12 beats) AVNRT. Additionally, in this group, both PRTCL and STD methods induced atrial tachycardia in two patients and orthodromic AV re-entrant tachycardia in one patient. CONCLUSION: Decremental ramp atrial extrastimuli pacing PRTCL demonstrates a superior response for induction of typical AVNRT as compared to STD techniques. Because of easy and reliable induction of AVNRT and echo beats by the PRTCL, we recommend it as a method to increase the likelihood of induction of AVNRT. For induction of other SVTs, the PRTCL and the STD methods are comparable.

Arrhythmias, Cardiac↗

PubMed2005

Electroanatomical mapping and radiofrequency catheter ablation of atrial tachycardia originating from the recipient heart with recipient-to-donor atrio-atrial conduction after orthotopic heart transplantation.

Atrial tachycardias resulting from recipient-to-donor atrio-atrial conduction after orthotopic heart transplantation are difficult to treat. We present two patients in whom atrial tachycardia originating in the recipient heart were successfully treated by radiofrequency ablation guided by electroanatomical CARTO mapping system. These cases illustrate that such atrial tachycardia are curable by radiofrequency ablation. Electroanatomical CARTO mapping is useful in identifying the site of origin of the tachycardia and the atrio-atrial conduction sites.

Aged↗

PubMed2004

Usefulness of pindolol for treatment of neurocardiogenic syncope.

This study evaluated the efficacy of pindolol, a noncardioselective beta blocker with intrinsic sympathetic activity, on neurocardiogenic syncope using a head-up tilt-table test in 66 patients. Pindolol was equally effective in men and women and the 2 age groups (>60 and <60 years) of the study cohort. The earliest benefit was seen </=3 days after initiating treatment. Side effects were better tolerated in younger patients (age <60 years).

Adolescent↗

PubMed2004

Pacemaker and defibrillator lead extraction.

PURPOSE OF REVIEW: Continued growth in the elderly population and expanding indications have resulted in a progressive increase in the number of implants of pacemakers and defibrillators. Concomitant with these expanding numbers, more leads require removal, due especially to mechanical dysfunction, the need to upgrade to more complex devices, or local or systemic infection. Further, leads have become more complex, particularly for defibrillator systems, resulting in the development of powered extraction sheaths to expedite their removal. For these reasons, it is important to understand the expanding indications, procedural aspects, and limitations of arrhythmia device extraction. RECENT FINDINGS: Expanded indications for lead extraction include upgrade to more complex systems, particularly pacemaker to defibrillator or biventricular device, extraction through occluded vasculature to produce a conduit for reimplantation, more frequent removal due to vascular overload with multiple leads, and a finite frequency of infection, occurring particularly with device replacement or revision. Powered sheaths now include laser and electrocautery systems, both improving the ease of lead explantation. SUMMARY: Complication rates remain low but constant with extraction of larger numbers of leads using new technologies. Expansion of the use of biventricular systems, with implantation of coronary sinus electrodes, will continue to challenge lead extraction in terms of technology and safety. Design of leads that are easier to remove remains of paramount importance.

Arrhythmias, Cardiac↗

PubMed2002

Dual-chamber pacing or ventricular backup pacing in patients with an implantable defibrillator: the Dual Chamber and VVI Implantable Defibrillator (DAVID) Trial.

CONTEXT: Implantable cardioverter defibrillator (ICD) therapy with backup ventricular pacing increases survival in patients with life-threatening ventricular arrhythmias. Most currently implanted ICD devices provide dual-chamber pacing therapy. The most common comorbid cause for mortality in this population is congestive heart failure. OBJECTIVE: To determine the efficacy of dual-chamber pacing compared with backup ventricular pacing in patients with standard indications for ICD implantation but without indications for antibradycardia pacing. DESIGN: The Dual Chamber and VVI Implantable Defibrillator (DAVID) Trial, a single-blind, parallel-group, randomized clinical trial. SETTING AND PARTICIPANTS: A total of 506 patients with indications for ICD therapy were enrolled between October 2000 and September 2002 at 37 US centers. All patients had a left ventricular ejection fraction (LVEF) of 40% or less, no indication for antibradycardia pacemaker therapy, and no persistent atrial arrhythmias. INTERVENTIONS: All patients had an ICD with dual-chamber, rate-responsive pacing capability implanted. Patients were randomly assigned to have the ICDs programmed to ventricular backup pacing at 40/min (VVI-40; n = 256) or dual-chamber rate-responsive pacing at 70/min (DDDR-70; n = 250). Maximal tolerated medical therapy for left ventricular dysfunction, including angiotensin-converting enzyme inhibitors and beta-blockers, was prescribed to all patients. MAIN OUTCOME MEASURE: Composite end point of time to death or first hospitalization for congestive heart failure. RESULTS: One-year survival free of the composite end point was 83.9% for patients treated with VVI-40 compared with 73.3% for patients treated with DDDR-70 (relative hazard, 1.61; 95% confidence interval [CI], 1.06-2.44). The components of the composite end point, mortality of 6.5% for VVI-40 vs 10.1% for DDDR-70 (relative hazard, 1.61; 95% CI, 0.84-3.09) and hospitalization for congestive heart failure of 13.3% for VVI-40 vs 22.6% for DDDR-70 (relative hazard, 1.54; 95% CI, 0.97-2.46), also trended in favor of VVI-40 programming. CONCLUSION: For patients with standard indications for ICD therapy, no indication for cardiac pacing, and an LVEF of 40% or less, dual-chamber pacing offers no clinical advantage over ventricular backup pacing and may be detrimental by increasing the combined end point of death or hospitalization for heart failure.

Adrenergic beta-Antagonists↗

PubMed2002

Quality of life in the antiarrhythmics versus implantable defibrillators trial: impact of therapy and influence of adverse symptoms and defibrillator shocks.

BACKGROUND: Implantable cardioverter defibrillator (ICD) use reduces mortality in patients with serious ventricular arrhythmias compared with antiarrhythmic drug (AAD) use. However, the relative impact of these therapies on self-perceived quality of life (QoL) is unknown. METHODS AND RESULTS: Three self-administered instruments were used to measure generic and disease-specific QoL in Antiarrhythmics Versus Implantable Defibrillators trial participants. Generalized linear models were used to assess the relationships between self-perceived QoL and treatment (AAD versus ICD) and adverse symptoms and ICD shocks. To minimize the impact of missing data, only patients surviving 1 year were included in the primary analyses. Baseline characteristics among QoL participants (n=905) and nonparticipants (n=111) were similar, but participants who survived 1 year (n=800) were healthier at baseline than nonsurvivors (n=105). Of the 800 patients in the primary analysis, characteristics of those randomized to AAD (n=384) versus ICD (n=416) were similar. Overall, ICD and AAD use were associated with similar alterations in QoL. The development of sporadic shocks and adverse symptoms were each associated with reduced physical functioning and mental well-being and increased concerns among ICD recipients, whereas development of adverse symptoms was associated with reduced physical functioning and increased concerns among AAD recipients. CONCLUSIONS: ICD and AAD therapy are associated with similar alterations in self-perceived QoL over 1-year follow-up. Adverse symptoms were associated with reduced self-perceived QoL in both groups, and sporadic shocks were associated with reduced QoL in ICD recipients.

Aged↗

PubMed2002

Effect of surgical revascularization in patients with coronary artery disease and ventricular tachycardia or fibrillation in the Antiarrhythmics Versus Implantable Defibrillators (AVID) Registry.

BACKGROUND: Patients who undergo resuscitation from near-fatal ventricular arrhythmias often have significant coronary artery disease, and revascularization has been shown to reduce myocardial ischemia and cardiac arrest episodes in this patient population. The magnitude of benefit attributed to revascularization has varied by study, and the use of adjunct implantable cardioverter defibrillator (ICD) therapy has not been well-characterized. METHODS AND RESULTS: The Antiarrhythmics Versus Implantable Defibrillators (AVID) registry included 3117 patients with life-threatening ventricular arrhythmias, of whom 2321 (77%) had documented coronary artery disease and 281 (17%) underwent a coronary artery bypass grafting revascularization procedure after the index event. Patients who underwent a revascularization procedure were younger, had a lower incidence rate of prior myocardial infarction and ventricular arrhythmia, had a higher left ventricular ejection fraction, had less congestive heart failure, and were more likely to have had ventricular fibrillation as the presenting arrhythmia. Patients who underwent revascularization had a better survival rate than did those who did not undergo such a procedure after the index event, and adjustment for differing baseline patient covariates did not alter the relative survival rate benefit. Further, ICD implantation offered a similar survival rate advantage to those patients in the AVID registry with coronary artery disease independent of revascularization. CONCLUSION: Coronary revascularization in the AVID registry patients with coronary artery disease effected a survival rate benefit that was not attributable to differences in baseline patient characteristics. The benefit of ICD on patient survival rate was not attenuated by a revascularization procedure.

Aged↗

PubMed2002

Prolonged sustained ventricular fibrillation without loss of consciousness in patients supported by a left ventricular assist device.

Patients with cardiomyopathy of either ischemic or nonischemic origin are at increased risk for malignant ventricular arrhythmias. Normally sustained ventricular fibrillation (VF) leads to death very rapidly. We report two patients who remained in sustained VF, supported by a left ventricular assist device, for a prolonged period of time. Perfusion pressure through the device was sufficient to allow the patients to remain awake and responsive for several hours while in VF. The cases represent two of the longest reported episodes of sustained VF recorded in awake patients implanted with such devices.

Aged↗

PubMed2002

Ventricular assist device support for management of sustained ventricular arrhythmias.

We describe herein the cases of 2 patients who had ventricular arrhythmias. In one, a short-term biventricular assist device, the ABIOMED BVS 5000, was placed because the patient had sustained ventricular tachycardia and could not be weaned from cardiopulmonary bypass. Excellent hemodynamic support was maintained for several days while the antiarrhythmic therapy was maximized. Sinus rhythm was restored, and the patient was successfully weaned from the ventricular assist device. However, the substrate for the arrhythmia persisted, and a recurrence, 1 week later, resulted in the patient's death. In the 2nd patient, the use of an implantable left ventricular assist device was successful in temporarily alleviating the ventricular tachycardia associated with ischemic cardiomyopathy. However, after 2 days of device assistance, the patient experienced a recurrence of the tachycardia, which degenerated into ventricular fibrillation with a marked deterioration in the patient's hemodynamics. The arrhythmia persisted despite multiple attempts at external cardioversion, and internal cardioversion and placement of an automatic implantable cardioverter-defibrillator were necessary. This treatment, along with repeated boluses of amiodarone, led to successful suppression of the arrhythmias, and the patient eventually underwent transplantation. The mechanical hemodynamic support of the circulation by ventricular assist devices was effective in supporting these 2 patients who had sustained ventricular arrhythmias.

Female↗

PubMedDate not supplied

Proarrhythmic effects of adenosine: one decade of clinical data.

In 1989, adenosine was introduced into the American clinical setting as an antiarrhythmic drug for the acute management of reentrant supraventricular tachycardia involving the atrioventricular node. During this decade of use, evidence for proarrhythmic effects of the drug have been documented. In addition to the mostly benign transient episodes of atrial fibrillation, several cases of life-threatening ventricular arrhythmias induced by adenosine have been reported. This article summarizes the proarrhythmic effects of adenosine as they were reported in the literature as well as data from the manufacturer files. The causes of these adverse effects of adenosine are analyzed, and factors to be considered before using the drug are discussed.

Adenosine↗