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Sedation with Midazolam for electrical cardioversion
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ABSTRACTS / Journal of Molecular and Cellular Cardiology 42 (2007) S1–S23
elicited at 0.2 Hz; ICaL amplitude and kinetics were measured by applying voltage protocols for steady-state activation and inactivation. T1AM significantly prolonged APD at − 20 mV and at 90% (22.2 ± 17.3 ms vs. 45.9 ± 17.2 ms at − 20 mV p < 0.005; 82 ± 55 ms vs. 266 ± 126 ms p < 0.05 at 90% ctr vs. T1AM), an effect associated with reduction of transient outward currents. T1AM did not affect ICaL amplitude (111.5% of control). In control, ICaL evoked from a holding potential (HP) of − 55 mV was greater than that elicited at HP = − 70 mV (124%) an effect known as facilitation. T1AM suppressed this phenomenon: ICaL measured at HP = − 55 mV was 99% of that measured at HP = − 70 mV. In control, ICaL inactivates with the typical bi-exponential decay (fast: 9 ± 2.6 ms; slow: 50 ± 10 ms). In the presence of T1AM, ICaL inactivated with a mono-exponential decay, the time constant being 26 ± 2 ms (p < 0.01 vs. control, fast). Thus, T1AM actions may reflect changes in cardiomyocyte calcium handling and affect heart inotropism. Keywords: Calcium channels; Myocytes; Signal transduction doi:10.1016/j.yjmcc.2007.03.061
Contact and non-contact mapping systems for ventricular tachycardia mapping and ablation C. Pratola* , T. Toselli* , E. Baldo* , P. Artale* , P. Notarstefano* , R. Ferrari* ,± . ⁎Chair of Cardiology, S. Anna University Hospital, Ferrara, Italy. ±Salvatore Maugeri Foundation, Gussago (BS), Italy Aim: To compare CARTO and Ensite NavX (contact) with Ensite Array (non-contact) mapping system for left ventricular tachycardia mapping and ablation. Methods: 40 patients with CAD with tolerated left ventricular tachycardia were randomized to a procedure with contact or non-contact system. The EP study consisted in arrhythmia induction, left ventricular mapping, ablation with a cooled tip catheter with a setting of 30W and 43C°. Results: 124 ventricular tachycardia morphologies were induced. The clinical one (mean circle length 370 ± 40 and 355 ± 35 ms respectively) was always induced. Anatomical mapping time was 15 min in the contact group and 5 min in the noncontact group. The ablation result of the clinical tachycardia was similar (90%). In 80% of both the groups faster morphologies were also induced. 60% of the 44 inducible morphologies were ablated in the contact group versus 77% of the 40 inducible in the non-contact group. Total procedural time in the 2 groups was 180 ± 28 and 130 ± 20 min. Discussion: Carto and NavX require the activation map of each tachycardia; the procedure is time consuming and only tolerated tachycardias can be mapped. Array is not easy to place into the left ventricle and mapping is difficult because of the presence of the balloon, but arrhythmia identification is fast and also fast tachycardias can be mapped. Procedural time was lower with non-contact mapping system.
Conclusion: Both systems are useful for ventricular tachycardia ablation. Array is a unique tool for ablation of fast morphologies. Keywords: Mapping System; Ventricular tachycardia doi:10.1016/j.yjmcc.2007.03.062
RF AF ablation: is the persistence of all intraprocedural targets necessary for long term sinus rhythm maintenance? E. Baldo* , C. Pratola* , P. Notarstefano* , T. Toselli* , P. Artale* , R. Ferrari* ,±. ⁎Chair of Cardiology, S. Anna University Hospital, Ferrara, Italy. ±Salvatore Maugeri Foundation, Gussago (BS) Aim: To evaluate the long term maintenance of intraprocedural endpoint of AF ablation procedures. Methods and results: Inclusion criteria were (1) previous ablation procedure of pulmonary veins (PVs) encircling performed for drug refractory persistent AF; (2) a “complete” intraprocedural end-point consisting in voltage abatement inside the lesions, PVs disconnection and exit block reached in all the PVs; (3) stable sinus rhythm (SR) documented by seriate ECG-Holter recording and transtelephonic monitoring during a mean follow up of 3 years after the procedure. 20 volunteers (12 males, mean age 59 ± 7 years) underwent a repeat electrophysiological study. At a FU of 36.4 ± 4.7 months, complete voltage abatement was maintained around 32 (40%) of the PVs, PV disconnection persisted in 12 (37.5%) of previously isolated PVs and exit block was present in 33 (41.25%) PVs. 10 patients (8 males, mean age 59.3 ± 6.7 years) who had the “complete” intraprocedural end-point reached during the first procedure and underwent a re-do ablation procedure because of recurrences were taken as control group. The differences in intraprocedural end-points maintenance in the 2 groups were not statistically significant. Conclusion: Common intraprocedural end-points of AF ablation seem to persist at long term follow up only in a limited number of patients in stable SR, as in patients undergoing repeat procedures because of recurrences. Further investigation will be required to determine whether such data will have implications for ablation strategies. Keywords: AF catheter ablation; PVs disconnection; PVs encircling doi:10.1016/j.yjmcc.2007.03.063
Sedation with Midazolam for electrical cardioversion P. Artale, C. Pratola, T. Toselli, E. Baldo, P. Notarstefano. Chair of Cardiology, University of Ferrara, and Cardiovascular Research Centre, S. Maugeri Foundation, Gussago (BS), Italy Background: Electrical cardioversion (ECV) requires the assistance of the anaesthesiology team. To avoid this
ABSTRACTS / Journal of Molecular and Cellular Cardiology 42 (2007) S1–S23
dependence, we have considered the use of sedation with intravenous midazolam administered by cardiologists. Methods: We performed 280 ECV in 202 patients sedated with intravenous midazolam, without anaesthesiology supervision. In scheduled cardioversions we tested two protocols of Midazolam administration: a bolus of 3 mg, followed by 2 mg each minute until necessary, and a loading dose of 0.09–0.1 mg/kg. In cardioversions performed during electrophysiology studies or defibrillator implant, Midazolam was administered by small repeated doses during the entire procedure. Results: Midazolam was effective to obtain adequate sedation in 99% of cases. All patients had amnesia with regards
S23
of the cardioversion. A loading dose of Midazolam allowed a shortening of the procedural time without serious adverse events. Intubation or the assistance of an Anaesthetist was never necessary. Conclusion: Sedation with Midazolam for ECV is effective and well tolerated, with some cautions discussed. A loading dose of Midazolam is well tolerated and further reduces the procedural time. Keywords: Electrical cardioversion; Midazolam doi:10.1016/j.yjmcc.2007.03.064
ABSTRACTS / Journal of Molecular and Cellular Cardiology 42 (2007) S1–S23
elicited at 0.2 Hz; ICaL amplitude and kinetics were measured by applying voltage protocols for steady-state activation and inactivation. T1AM significantly prolonged APD at − 20 mV and at 90% (22.2 ± 17.3 ms vs. 45.9 ± 17.2 ms at − 20 mV p < 0.005; 82 ± 55 ms vs. 266 ± 126 ms p < 0.05 at 90% ctr vs. T1AM), an effect associated with reduction of transient outward currents. T1AM did not affect ICaL amplitude (111.5% of control). In control, ICaL evoked from a holding potential (HP) of − 55 mV was greater than that elicited at HP = − 70 mV (124%) an effect known as facilitation. T1AM suppressed this phenomenon: ICaL measured at HP = − 55 mV was 99% of that measured at HP = − 70 mV. In control, ICaL inactivates with the typical bi-exponential decay (fast: 9 ± 2.6 ms; slow: 50 ± 10 ms). In the presence of T1AM, ICaL inactivated with a mono-exponential decay, the time constant being 26 ± 2 ms (p < 0.01 vs. control, fast). Thus, T1AM actions may reflect changes in cardiomyocyte calcium handling and affect heart inotropism. Keywords: Calcium channels; Myocytes; Signal transduction doi:10.1016/j.yjmcc.2007.03.061
Contact and non-contact mapping systems for ventricular tachycardia mapping and ablation C. Pratola* , T. Toselli* , E. Baldo* , P. Artale* , P. Notarstefano* , R. Ferrari* ,± . ⁎Chair of Cardiology, S. Anna University Hospital, Ferrara, Italy. ±Salvatore Maugeri Foundation, Gussago (BS), Italy Aim: To compare CARTO and Ensite NavX (contact) with Ensite Array (non-contact) mapping system for left ventricular tachycardia mapping and ablation. Methods: 40 patients with CAD with tolerated left ventricular tachycardia were randomized to a procedure with contact or non-contact system. The EP study consisted in arrhythmia induction, left ventricular mapping, ablation with a cooled tip catheter with a setting of 30W and 43C°. Results: 124 ventricular tachycardia morphologies were induced. The clinical one (mean circle length 370 ± 40 and 355 ± 35 ms respectively) was always induced. Anatomical mapping time was 15 min in the contact group and 5 min in the noncontact group. The ablation result of the clinical tachycardia was similar (90%). In 80% of both the groups faster morphologies were also induced. 60% of the 44 inducible morphologies were ablated in the contact group versus 77% of the 40 inducible in the non-contact group. Total procedural time in the 2 groups was 180 ± 28 and 130 ± 20 min. Discussion: Carto and NavX require the activation map of each tachycardia; the procedure is time consuming and only tolerated tachycardias can be mapped. Array is not easy to place into the left ventricle and mapping is difficult because of the presence of the balloon, but arrhythmia identification is fast and also fast tachycardias can be mapped. Procedural time was lower with non-contact mapping system.
Conclusion: Both systems are useful for ventricular tachycardia ablation. Array is a unique tool for ablation of fast morphologies. Keywords: Mapping System; Ventricular tachycardia doi:10.1016/j.yjmcc.2007.03.062
RF AF ablation: is the persistence of all intraprocedural targets necessary for long term sinus rhythm maintenance? E. Baldo* , C. Pratola* , P. Notarstefano* , T. Toselli* , P. Artale* , R. Ferrari* ,±. ⁎Chair of Cardiology, S. Anna University Hospital, Ferrara, Italy. ±Salvatore Maugeri Foundation, Gussago (BS) Aim: To evaluate the long term maintenance of intraprocedural endpoint of AF ablation procedures. Methods and results: Inclusion criteria were (1) previous ablation procedure of pulmonary veins (PVs) encircling performed for drug refractory persistent AF; (2) a “complete” intraprocedural end-point consisting in voltage abatement inside the lesions, PVs disconnection and exit block reached in all the PVs; (3) stable sinus rhythm (SR) documented by seriate ECG-Holter recording and transtelephonic monitoring during a mean follow up of 3 years after the procedure. 20 volunteers (12 males, mean age 59 ± 7 years) underwent a repeat electrophysiological study. At a FU of 36.4 ± 4.7 months, complete voltage abatement was maintained around 32 (40%) of the PVs, PV disconnection persisted in 12 (37.5%) of previously isolated PVs and exit block was present in 33 (41.25%) PVs. 10 patients (8 males, mean age 59.3 ± 6.7 years) who had the “complete” intraprocedural end-point reached during the first procedure and underwent a re-do ablation procedure because of recurrences were taken as control group. The differences in intraprocedural end-points maintenance in the 2 groups were not statistically significant. Conclusion: Common intraprocedural end-points of AF ablation seem to persist at long term follow up only in a limited number of patients in stable SR, as in patients undergoing repeat procedures because of recurrences. Further investigation will be required to determine whether such data will have implications for ablation strategies. Keywords: AF catheter ablation; PVs disconnection; PVs encircling doi:10.1016/j.yjmcc.2007.03.063
Sedation with Midazolam for electrical cardioversion P. Artale, C. Pratola, T. Toselli, E. Baldo, P. Notarstefano. Chair of Cardiology, University of Ferrara, and Cardiovascular Research Centre, S. Maugeri Foundation, Gussago (BS), Italy Background: Electrical cardioversion (ECV) requires the assistance of the anaesthesiology team. To avoid this
ABSTRACTS / Journal of Molecular and Cellular Cardiology 42 (2007) S1–S23
dependence, we have considered the use of sedation with intravenous midazolam administered by cardiologists. Methods: We performed 280 ECV in 202 patients sedated with intravenous midazolam, without anaesthesiology supervision. In scheduled cardioversions we tested two protocols of Midazolam administration: a bolus of 3 mg, followed by 2 mg each minute until necessary, and a loading dose of 0.09–0.1 mg/kg. In cardioversions performed during electrophysiology studies or defibrillator implant, Midazolam was administered by small repeated doses during the entire procedure. Results: Midazolam was effective to obtain adequate sedation in 99% of cases. All patients had amnesia with regards
S23
of the cardioversion. A loading dose of Midazolam allowed a shortening of the procedural time without serious adverse events. Intubation or the assistance of an Anaesthetist was never necessary. Conclusion: Sedation with Midazolam for ECV is effective and well tolerated, with some cautions discussed. A loading dose of Midazolam is well tolerated and further reduces the procedural time. Keywords: Electrical cardioversion; Midazolam doi:10.1016/j.yjmcc.2007.03.064