Showing papers by "Sanjeev Saksena published in 1991"

Implantable cardioverter defibrillators in cardiovascular practice: report of the Policy Conference of the North American Society of Pacing and Electrophysiology. NASPE Policy Conference Committee.

Abstract: NASPE Policy Conference Committee: Michael H. Lehmann, Wayne State University/Harper Hospital, Detroit. Michigan; Sanjeev Saksena, UMDNJ NJ Medical School, Newark. New Jersey, Co-Chairs; Masood Akhtar, Sinai Samaritan Medical Center, Milwaukee, Wisconsin; J. Thomas Bigger. Jr., Columbia Presbyterian, New York. New York; A. John Camm, St. George's Hospital Medical School, London, England; Elizabeth J. Darling, Indianapolis, Indiana; Leonard Dreifus, Likoff Cardiovascular Institute, Philadelphia, Pennsylvania; Margaret Eaust, Nashville, Tennessee; John D. Eisher and Seymour Eurman, Montefiore Medical Center, Bronx, New York; Nora E. Goldschlager, San Erancisco General Hospital, San Eransisco, California; Jerry C. Griffin, Moffitt Hospital, University of California San Erancisco, San Erancisco, California; Thomas Guarnieri, John Hopkins Hospital, Baltimore, Maryland; Gerard M. Guiraudon, University Hospital, London, Ontario, Canada; J. Warren Harthorne and Jeremy N. Ruskin, Massachusetts General Hospital, Boston, Massachusetts; Richard M. Luceri, Eort Lauderdale, Elorida; James D. Maloney, The Cleveland Clinic Eoundation, Cleveland, Ohio; Erancis E. Marchiinski, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; Robert J. Myerburg, University of Miami School of Medicine, Miami, Elorida; Lois Schurig, Oakwood Health Sciences, Detroit, Michigan; Gerald G. Timmis, William Beaumont Hospital, Royal Oak, Michigan; Albert L. Waldo, University Hospital of Cleveland, Cleveland, Ohio; Salim Yusuf, National Institute of Health, Bethesda, Maryland; Douglas P. Zipes, Krannert Institute of Cardiology, Indianapolis, Indiana.

Experience with a third-generation implantable cardioverter-defibrillator.

Abstract: A Medtronic 7216A pacemaker cardioverter-defibrillator was implanted in 16 patients (mean age 56 years) with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) and organic heart disease with a mean left ventricular ejection fraction of 33%. Endocardial and epicardial defibrillation shock efficacy was evaluated before or at implant using 1 to 3 shock patterns, i.e., monophasic single, sequential or simultaneous shocks with dual and triple electrode configurations. Endocardial leads used a common right ventricular cathode and dual anodes, whereas epicardial leads used 2 or 3 helical coil patches. VT termination was evaluated using pacing or shock therapy, or both, whereas only shocks were used in VF. Programmable bradycardia pacing, individual zones for VT and VF detection and individualized pacing and shock therapy for VT and VF were used. Monophasic shocks had epicardial defibrillation thresholds ranging from 3 to 18 (mean 10) J and were comparable for sequential and simultaneous shocks (p > 0.2). VT detection rates ranged from 340 to 470 ms and VF detection rates from 270 to 330 ms. VT or VF induction, or both, was performed noninvasively in 13 patients after implant and was reproducibly terminated by rapid pacing alone (5 patients), low-energy shocks (2 patients), high-energy shocks (3 patients) and combined therapy (3 patients). Intermediate or highenergy shocks terminated all induced VF episodes. During follow-up (2 to 12 months), there have been 2 noncardiac deaths. Electrical therapy was delivered in 7 patients, for VT (3 patients), VT and VF (3 patients) and indeterminate tachyarrhythmia (1 patient). All sol VT VF episodes were successfully terminated, with 78 of 96 (81%) spontaneous VT episodes terminated by pacing. Follow-up reprogramming was required n 5 patients. It is concluded that successful application of individualized electrical therapy prescriptions in patients with VT/VF is feasible. Pacing therapies, which are effective for induced VT, can be reliably used for effective long-term spontaneous VT termination in conjunction with shock therapy and can permit reduced patient exposure to shock therapy. Thus, a programmable hybrid pacemaker cardioverter-defibrillator system provides nonthoracotomy implantation, effective sol VT VF termination, demand ventricular pacing and noninvasive modes for arrhythmia induction, event monitoring and clinical troubleshooting.

Simultaneous Biphasic Shocks Enhance Efficacy of Endocardial Cardioversion Defibrillation in Man

Abstract: Endocardial lead systems are heing clinicaUy investigated for implantable cardioverter defibrillators (ICDs). Successful reversion of ventricular tachycardia (VT) and ventricular fibrillation (VF) with endocardial shocks has been reported.'-^ Initial attempts using two defibrillation electrodes on a single catheter were unsuccessful due to low efficacy rates and poor reliability secondary to high defibrillation thresholds.^ Acceleration of VT with low energy shocks was also frequently observed.'*-^ Reliable endocardial cardioversion and defibrillation has required use of a triple electrode system and high energy monophasic shocks.^'* We have previously extensively evaluated this approach and noted that most patients can be reliably defibrillated using a single common right ventricular cathode and dual anodes in the superior vena cava/right atrium and left thorax with ^ 25 joules (J) monophasic truncated exponential shocks.^ Different reports have suggested that 10% to 30% of patients may not be reliably defibrillated with this approach.^\" Efforts to decrease or eliminate the residual refractory patients have been varied. We have suggested that detailed mapping of optimal patch electrode position on the left thorax may be of value in this group.^••'•'\" Others have suggested cathode repositioning, reversing intracardiac electrode polarity or use of other sites such as the coronary sinus.\"'*^ Extensive intraoperative