LOW-ENERGY ENDOCARDIAL DEFIBRILLATION USING AN AXILLARY OR A PECTORALTHORACIC ELECTRODE LOCATION

Citation
S. Saksena et al., LOW-ENERGY ENDOCARDIAL DEFIBRILLATION USING AN AXILLARY OR A PECTORALTHORACIC ELECTRODE LOCATION, Circulation, 88(6), 1993, pp. 2655-2660
Citations number
15
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Cardiac & Cardiovascular System",Hematology
Journal title
Circulation → ACNP
ISSN journal
0009-7322
Volume
88
Issue
6
Year of publication
1993
Pages
2655 - 2660
Database
ISI
SICI code
0009-7322(1993)88:6<2655:LEDUAA>2.0.ZU;2-X
Abstract
Background. A significant proportion of patients receiving endocardial defibrillation lead systems must accept either high defibrillation th resholds (DFTs) with lower safety margins or lead implantation by thor acotomy. We examined the feasibility of achieving universal applicatio n of endocardial leads and lower defibrillation energy requirements by optimizing the lead system location in conjunction with biphasic shoc ks. Methods and Results. Two defibrillation catheter electrodes were p ositioned in the right ventricle and superior vena cava. Thoracic patc h electrodes were placed at three sites (apical, pectoral, and axillar y). Fifteen-joule, 10-J, and 5-J bidirectional simultaneous biphasic s hocks were delivered across three different triple electrode configura tions (right ventricle, superior vena cava, and patch) after inducing ventricular fibrillation (VF), and DFT was determined. All patients in whom VF was reproducibly inducible (14 patients) could be reproducibl y defibrillated at 15 J at one or more patch electrode locations. Fift een-joule shocks were effective at three thoracic electrode locations in 12 patients and at two electrode locations in 6 patients. The lowes t mean single-shock DFT was 8.1+/-3.8 J. In 4 patients, ventricular bu tter was reproducibly induced and reverted at 15 J in all patients. Me an DFT for the axillary location was 8.3+/-3.5 J and was significantly lower than apical (12.8+/-5.6 J, P=.008) and pectoral (11.6+/-4.1 J, P<.04) patch locations. The probability of success was significantly h igher at 10 J with axillary location (78% of patients, P<.03 compared with both other sites) and at 15 J (P<.05 compared with the apical loc ation). Low-energy endocardial defibrillation (less than or equal to 1 0 J) was feasible in 10 of 14 tested patients at more than 1 thoracic electrode location at 10 J, whereas only 1 of 7 successful patients co uld be reverted at more than 1 electrode location at 5 J (P<.02). Conc lusions. The use of axillary or pectoral patch lead location can allow endocardial defibrillation with biphasic shocks at energies less than or equal to 15 J in this lead configuration. Virtually universal appl ication of endocardial defibrillation lead systems can be predicted fr om these data. Reduction in maximum pulse generator output to less tha n or equal to 25 J using these two thoracic electrode locations with b idirectional shocks can be feasible and maintain an adequate safety ma rgin and permit thoracic pulse generator implantation. Lowering endoca rdial defibrillation energy <10 J requires increasing specificity of t horacic electrode location.