Electrophysiologist-implanted transvenous cardioverter defibrillators using local versus general anesthesia

Pain During "Noncomplex" Electrophysiological Studies and Cardiac Rhythm Device Surgery

BACKGROUND

There are only limited data about peri-interventional pain during cardiac electrophysiological procedures without analgosedation. In this study, peri-interventional pain and recollection of it after the intervention were evaluated.

METHODS

A total of 101 patients (43 electrophysiological/ablation procedures and 58 device surgeries) reported pain on a numerical rating scale (NRS; 0-10) before (pre), during (peri), and after (post) the intervention. Maximum pain (maxNRS) and the average of pain (meanNRS) were used for statistical analysis. Peri-interventional pain was compared with postinterventional data of the recollection of peri-interventional pain (peri-post). Patients were allocated into 2 groups (with 51 and 50 patients, respectively) to evaluate the mode of patient-staff interaction on pain recollection. Depressive, anxiety, and somatic symptom scales (Patient Health Questionnaire-15, Generalized Anxiety Disorder-7, and Patient Health Questionnaire-15) were used to analyze their influence on pain recollection.

RESULTS

In total, 49.6% of patients (n = 50) complained of moderate to severe pain (maxNRS) at least once during the procedure. The comparison between peri and peri-post data revealed the following (median (range)-maxNRS, peri: 3 (0-10) versus peri-post: 4 (0-9) (ns), and meanNRS, peri: 1.4 (0-7) versus peri-post: 2.0 (0-6) (ns). The mode of patient-staff interaction had no influence on pain. No effect was found for psychosocial factor concerning pain and the recollection of pain. The results of the linear regression showed no influence of low-dose midazolam on recollection of pain.

CONCLUSION

Half of the patients reported moderate to severe pain at least once during cardiac electrophysiological procedures without analgosedation. However, on average, patients reported only low pain levels. Postinterventional derived data on discomfort reflect the peri-interventional situation.

Feasibility and safety of using local anaesthesia with conscious sedation during complex cardiac implantable electronic device procedures

We assessed the feasibility and safety of using local anaesthesia with conscious sedation as an alternative to general anaesthesia during complex and noncomplex cardiac implantable device procedures. We enrolled 279 consecutive patients who underwent cardiac device implantation/replacement at our tertiary/quaternary cardiac specialist hospital during a 17-month study period. Continuous combined intravenous conscious sedation with propofol and midazolam plus fentanyl and local anaesthesia were used for all procedures. Among the patients, 113, 59, 43, and 64 patients underwent pacemaker implantation, implantable cardiac defibrillator implantation, cardiac resynchronisation therapy device implantation, and generator exchange, respectively. The procedural success rate was 100%, with no apnoea or hypoxia episodes requiring therapeutic intervention. None of the patients required conversion to general anaesthesia. The mean surgical duration was longer for complex vs. noncomplex procedures (p = 0.003). The minimum mean arterial pressure during complex procedures was slightly lower than that during noncomplex procedures (p = 0.03). The perioperative (<24 h) mortality rate was 0%, and neither complexity group required tracheal intubation. Only two patients (0.7%) required unplanned intensive care unit admission for further surveillance. Our findings suggest that local anaesthesia with conscious sedation is a safe and feasible option for cardiac device implantation procedures, including complex procedures.

Cardiac implantable electronic device lead extraction using the lead-locking device system: keeping it simple, safe, and inexpensive with mechanical tools and local anesthesia

Objective:

We have previously reported our successful approach for percutaneous cardiac implantable electronic device (CIED) lead extraction using inexpensive tools, which we have continued over the years. Herein we report the results of the systematic use of a unique stylet, the lead-locking device (LLD), which securely locks the entire lead lumen, aided with non-powered telescoping sheaths in 54 patients to extract 98 CIED leads.

Methods:

This prospective observational clinical study included 38 men and 16 women aged 68.9±13.1 years undergoing lead extraction for device infection (n=46), lead malfunction (n=5), or prior to defibrillator implant (n=3). Leads were in place for 6.7±4.3 years. Infections were more commonly due to Staphylococcus species (n=40). There were 78 pacing (31 ventricular, 37 atrial, 4 VDD, and 6 coronary sinus leads) and 20 defibrillating leads.

Results:

Using simple traction (6 leads) and the LLD stylets (92 leads) aided with telescoping sheaths (15 patients), 96 (98%) leads in 52 (96.3%) patients were successfully removed, with all but one leads removed using a subclavian approach; in 1 patient, the right femoral approach was also required. In 2 patients, distal fragments from one ventricular pacing and one defibrillating lead could not be removed. Finally, lead removal was completely (52/54) (96.3%) or partially (2/54) (3.7%) successful in 54 patients for 96 of 98 leads (98%) without major complications.

Conclusion:

Percutaneous lead extraction can be successful with mechanical tools using the LLD locking stylet aided with non-powered telescoping sheaths through a simplified, safe, and inexpensive procedure using local anesthesia alone.

"Real life" longevity of implantable cardioverter-defibrillator devices

BACKGROUND

Manufacturers of implantable cardioverter-defibrillators (ICDs) promise a 5- to 9-year projected longevity; however, real-life data indicate otherwise. The aim of the present study was to assess ICD longevity among 685 consecutive patients over the last 20 years.

HYPOTHESIS

Real-life longevity of ICDs may differ from that stated by the manufacturers.

METHODS

The study included 601 men and 84 women (mean age, 63.1 ± 13.3 years). The underlying disease was coronary (n = 396) or valvular (n = 15) disease, cardiomyopathy (n = 220), or electrical disease (n = 54). The mean ejection fraction was 35%. Devices were implanted for secondary (n = 562) or primary (n = 123) prevention. Single- (n = 292) or dual-chamber (n = 269) or cardiac resynchronization therapy (CRT) devices (n = 124) were implanted in the abdomen (n = 17) or chest (n = 668).

RESULTS

Over 20 years, ICD pulse generator replacements were performed in 238 patients (209 men; age 63.7 ± 13.9 years; ejection fraction, 37.7% ± 14.0%) who had an ICD for secondary (n = 210) or primary (n = 28) prevention. The mean ICD longevity was 58.3 ± 18.7 months. In 20 (8.4%) patients, devices exhibited premature battery depletion within 36 months. Most (94%) patients had none, minor, or modest use of ICD therapy. Longevity was longest for single-chamber devices and shortest for CRT devices. Latest-generation devices replaced over the second decade lasted longer compared with devices replaced during the first decade. When analyzed by manufacturer, Medtronic devices appeared to have longer longevity by 13 to 18 months.

CONCLUSIONS

ICDs continue to have limited longevity of 4.9 ± 1.6 years, and 8% demonstrate premature battery depletion by 3 years. CRT devices have the shortest longevity (mean, 3.8 years) by 13 to 17 months, compared with other ICD devices. These findings have important implications, particularly in view of the high expense involved with this type of electrical therapy.

Sedation for electrophysiological procedures

Administration of intravenous sedation (IVS) has become an integral component of procedural cardiac electrophysiology. IVS is employed in diagnostic and ablation procedures for transcutaneous treatment of cardiac arrhythmias, electrical cardioversion of arrhythmias, and the insertion of implantable electronic devices including pacemakers, defibrillators, and loop recorders. Sedation is frequently performed by nursing staff under the supervision of the proceduralist and in the absence of specialist anesthesiologists. The sedation requirements vary depending on the nature of the procedure. A wide range of sedation techniques have been reported with sedation from the near fully conscious to levels approaching that of general anesthesia. This review examines the methods employed and outcomes associated with reported sedation techniques. There is a large experience with the combination of benzodiazepines and narcotics. These drugs have a broad therapeutic range and the advantage of readily available reversal agents. More recently, the use of propofol without serious adverse events has been reported. The results provide a guide regarding the expected outcomes of these approaches. The complication rate and need for emergency assistance is low in reported series where sedation is administered by nonspecialist anesthesiology staff.

Managing anticoagulation in patients receiving implantable cardiac devices

A substantial proportion of patients who undergo cardiac rhythm device implantation receive anticoagulation to prevent thromboembolism. Many patients have coexisting cardiovascular diseases treated with antiplatelet therapy. Anticoagulation may increase the risk of hemorrhagic complication, while withdrawal of anticoagulation may increase thromboembolic risk. In this article, we review and describe the available evidence, in order to inform best practice .

Phantom shocks unmasked: clinical data and proposed mechanism of memory reactivation of past traumatic shocks in patients with implantable cardioverter defibrillators

BACKGROUND

Implantable cardioverter defibrillators (ICD), despite an unequivocal clinical benefit, are known to have a complex psychosocial impact on the patients. ICD shocks and the resultant psychobiological changes are known to contribute to increased levels of anxiety, depression, and post-shock stress symptoms in these patients. Phantom shock is a patient-reported perception of an ICD shock in the absence of any actual shock; however, its pathophysiological understanding is poor.

METHODS

A retrospective chart review of the University hospital ICD patients' database from June 2006 to April 2010 was conducted. A total of 38 patients with documented phantom shocks as cases and 76 age- and sex-matched patients with no phantom shocks as controls were selected from the database. Patient characteristics were analyzed for their potential association with the occurrence of phantom shocks.

RESULTS

Phantom shock patients had higher prevalence of documented depression (31.6%), anxiety (23.7%), and cocaine use (42.1%). Additionally, patients who had previous ICD shock storms were more likely to have phantom shocks (39.5%; p = 0.001). More importantly, no phantom shocks were reported in patients who did not receive defibrillation threshold testing or past ICD shock storms.

CONCLUSIONS

Phantom shocks are primarily observed in ICD patients who had prior exposure to traumatic device shocks and are more common in patients with a history of depression, anxiety, or substance abuse. A pathophysiological mechanism is proposed as a guide to potential prevention.

[Implantation of cardioverter-defibrillators. How much anesthesia is necessary?]

Updated cardiologic guidelines constitute the background for an extended spectrum of indications for the implantation of automatic implantable cardioverter defibrillators (AICDs) and lead to an increasing number of operative implantations of AICDs. Moreover, during implantation of devices for cardiac resynchronization therapy the anesthesiologist is responsible for the most critically ill patients with the longest duration of surgery. As a result anesthesiologists face an increasing number of critically ill patients, whose management contributes to perioperative outcome. Automatic implantable cardioverter defibrillators can be implanted either during general anesthesia, local anesthesia or during a combination of local anesthesia combined with deep conscious sedation accomplished by an anesthesiologist. Besides economic aspects there is an increasing demand for anesthesia with the least cardiovascular side effects and rapid recovery in the often seriously ill patient with preexisting limitations of cardiac and pulmonary functions. Accordingly procedure and anesthesia-associated risks are reviewed and an algorithm for anesthesia management is suggested.

The dilemma of ICD implant testing

Ventricular fibrillation (VF) has been induced at implantable cardioverter defibrillator (ICD) implant to ensure reliable sensing, detection, and defibrillation. Despite its risks, the value was self-evident for early ICDs: failure of defibrillation was common, recipients had a high risk of ventricular tachycardia (VT) or VF, and the only therapy for rapid VT or VF was a shock. Today, failure of defibrillation is rare, the risk of VT/VF is lower in some recipients, antitachycardia pacing is applied for fast VT, and vulnerability testing permits assessment of defibrillation efficacy without inducing VF in most patients. This review reappraises ICD implant testing. At implant, defibrillation success is influenced by both predictable and unpredictable factors, including those related to the patient, ICD system, drugs, and complications. For left pectoral implants of high-output ICDs, the probability of passing a 10 J safety margin is approximately 95%, the probability that a maximum output shock will defibrillate is approximately 99%, and the incidence of system revision based on testing is < or = 5%. Bayes' Theorem predicts that implant testing identifies < or = 50% of patients at high risk for unsuccessful defibrillation. Most patients who fail implant criteria have false negative tests and may undergo unnecessary revision of their ICD systems. The first-shock success rate for spontaneous VT/VF ranges from 83% to 93%, lower than that for induced VF. Thus, shocks for spontaneous VT/VF fail for reasons that are not evaluated at implant. Whether system revision based on implant testing improves this success rate is unknown. The risks of implant testing include those related to VF and those related to shocks alone. The former may be due to circulatory arrest alone or the combination of circulatory arrest and shocks. Vulnerability testing reduces risks related to VF, but not those related to shocks. Mortality from implant testing probably is 0.1-0.2%. Overall, VF should be induced to assess sensing in approximately 5% of ICD recipients. Defibrillation or vulnerability testing is indicated in 20-40% of recipients who can be identified as having a higher-than-usual probability of an inadequate defibrillation safety margin based on patient-specific factors. However, implant testing is too risky in approximately 5% of recipients and may not be worth the risks in 10-30%. In 25-50% of ICD recipients, testing cannot be identified as either critical or contraindicated.

Can we implant cardioverter defibrillator under minimal sedation?

Aim In a prospective study, we tested the feasibility of implantable cardioverter-defibrillator (ICD) implantation under local anaesthesia (LA) with minimal sedation (MS) vs. short general anaesthesia (SGA) for defibrillation test (DT).

METHODS AND RESULTS

We implanted ICDs in 118 patients between October 2002 and November 2003. Surgery was performed under LA with MS. Depending on the day of admission, patients had DT without SGA with a shock delivered when patient is unconscious (MS group, n = 73) or with short general anaesthesia (SGA group, n = 45). The patients were asked to rate the intensity of pain on a 10-point visual analogue scale (VAS) at the end of the implantation procedure and for the patient of MS group just after DT (VAS-DT). Visual analogue scale was not influenced by the type of anaesthesia (MS vs. SGA). Univariate analysis showed that NYHA >III, 3 leads implanted and an incomplete understanding of the explanation on the procedure were risk factors of VAS >4. Only understanding of the explanation on the procedure has an influence on pain in multivariate analysis.

CONCLUSION

ICD implantation under MS even for DT is feasible and acceptable for the patient.

Subpectoral cardioverter-defibrillator implantation using a lateral approach

INTRODUCTION

Third-generation cardioverter-defibrillators have revolutionized management of ventricular tachyarrhythmias. Implantation can be performed in the electro-physiology laboratory, with minimal morbidity. Generator size has shrunk to the point that subcutaneous implantation is feasible and safe, even under local anesthesia. The prepectoral technique, however, is associated with increased mechanical stress to the subcutaneous tissue and can predispose to device erosion or infection. These complications may be avoided by submuscular placement. Among subpectoral techniques, the lateral approach offers unrestricted ability to deploy patches or array electrodes, should the need arise, and may represent the optimal implant technique under some circumstances.

METHODS

We studied 29 male patients, aged 29-78 years, who presented with syncope or sustained ventricular tachycardia, and underwent subpectoral defibrillator implantation under general anesthesia or conscious sedation. All devices were third-generation active can systems with biphasic shock capability. Six dual-chamber defibrillators were used.

RESULTS

Subpectoral implantation was successful in all cases, with an estimated blood loss of 28+/-17 mL and no immediate complications. Except for one patient who developed twiddler's syndrome and ultimately required revision to a subcutaneous pocket, the implant site was tolerated well, and no limitation in the range of motion of the upper limb was observed during 20 months of follow-up.

CONCLUSIONS

Subpectoral implantation using a lateral approach is technically straightforward and can be applied globally, with modest additional resource and equipment requirements. Familiarity with this approach can maximize the likelihood of successful defibrillator implantation in the electrophysiology laboratory.

Two-coil versus single-coil transvenous cardioverter defibrillator systems: comparative data

Two types of new-generation transvenous implantable cardioverter defibrillator (ICD) systems, incorporating a two-coil (62 patients, group 1) versus single-coil (32 patients, group 2) lead system were compared among 94 consecutive patients. The two groups were comparable in age (58 +/- 13 vs 59 +/- 14 years), presenting arrhythmia (ventricular tachycardia versus ventricular fibrillation 77%/21% vs 84%/13%), cycle length of induced VT (294 +/- 4 vs 289 +/- 44 ms), number of unsuccessful antiarrhythmic drugs (1.7 +/- 0.8 vs 1.7 +/- 0.7), and left ventricular ejection fraction (35 +/- 12% vs 34 +/- 9%). Both systems were successfully implanted strictly transvenously in all patients. Biphasic shocks were used in all patients. Active shell devices were used in 79% and 84% patients of groups I and II, respectively (P = NS). Intraoperative testing revealed comparable defibrillation threshold (DFT) values (10.2 +/- 3.7 J in group 1 versus 9.3 +/- 3.6 J in group 2 system), and pacing threshold (0.7 +/- 0.3 vs 0.7 +/- 0.3 V), but R wave amplitude and lead impedance were lower in group 1 (13 +/- 5 vs 16 +/- 5 mV, P = 0.003; and 579 +/- 115 vs 657 +/- 111 ohms, P = 0.002, respectively). Lead insulation break requiring reoperation occurred in one patient with an Endotak lead, and two patients with Transvene leads had initially high DFT with a single one-lead/active can system, which was converted to a two- or three-endocardial-lead/inactive can configuration. We conclude that both single-coil and two-coil transvenous ICD systems were associated with high rates of successful strictly transvenous ICD implantation and a low incidence of lead-related complications. Significant differences were noted in the sensed R wave and lead impedance, probably reflecting the active fixation characteristics of the Transvene lead. However, in order to obviate the sporadic need for implantation of additional endocardial leads, as was the case in two patients in this series, a double-coil lead may be preferable.