Remifentanil–Midazolam Sedation Provides Hemodynamic Stability and Comfort During Epicardial Ablation of Ventricular Tachycardia

Remifentanil for Epicardial VT Ablation . Epicardial ablation of ventricular tachycardia (VT) presents multiple challenges for anesthetic management. General anesthesia lowers blood pressure, may interfere with arrhythmia mapping, and use of muscle relaxants precludes identification of the phrenic nerve. We describe a case in which remifentanil with minimal doses of midazolam was employed in a series of epicardial VT ablations and noninvasive programmed stimulations (NIPS), including 5 external cardioversions and discuss the advantages of this approach. (J Cardiovasc Electrophysiol, Vol. 22, pp. 464‐466)     

Harder Roads to Trek? Paradoxical Slowing of an Atrioventricular Reentrant Tachycardia With Contralateral Bundle Branch Block

Slowing of the tachycardia with increase in cycle length and increase in VA time with ipsilateral bundle branch block is a characteristic feature of accessory pathway mediated AVRT. Contralateral bundle branch block has no effect on the tachycardia as it is not a part of the tachycardia circuit. We present an interesting phenomenon in which contralateral bundle branch block resulted in tachycardia slowing in a case of WPW syndrome.     

Social determinants of cardiovascular reactivity: Effects of incentive to exert influence and evaluative threat

The effects on cardiovascular reactivity of incentive to influence the judgements of the experimenter and the threat of social evaluation were examined in a sample of 60 male and 60 female undergraduates. Participants either were guaranteed $5.00 to prepare and deliver a brief speech or were told that the money was contingent on an evaluation by the experimenter. Participants believed that their speech would be rated for either simple clarity or verbal intelligence. The contingent incentive increased systolic blood pressure reactivity by 6.5 mmHg (32%). Evaluative threat increased systolic reactivity by 7.1 mmHg (36%). These interpersonal processes could increase the risk of cardiovascular disease and are likely to affect the degree of cardiovascular reactivity in laboratory studies.     

Postoperative Low‐Molecular‐Weight Heparin Bridging Is Associated with an Increase in Wound Hematoma Following Surgery for Pacemakers and Implantable Defibrillators

Background: The perioperative management of patients receiving oral anticoagulation therapy (OAC) who undergo pacemaker (PM) and defibrillator (ICD) surgery remains controversial. Low‐molecular‐weight heparin (LMWH) is often used; however, wound hematoma is a common complication. Methods: At a single academic Canadian center, between July 2003 and June 2005, details of perioperative OAC bridging and the rate of wound hematoma requiring reoperation or interruption of OAC were reviewed for all patients receiving LMWH bridging for PM or ICD surgery. Results: A total of 148 PM/ICD patients underwent perioperative bridging with LMWH. A significant hematoma occurred in 23 patients, requiring reoperation in three patients. No patient died, developed infection, or stroke. The initial bridging regimen included LMWH (enoxaparin 1 mg/kg BID) given until evening prior to surgery, and reinitiated on postoperative day 3. In response to high rates of postoperative hematoma, subsequent protocols omitted the LMWH on the evening before surgery, all postoperative LMWH, or both. The use of LMWH the night before surgery had no effect on hematoma rates (12% vs 17%, P = 0.62); however, the use of any postoperative LMWH increased hematoma rates (23% vs 8%, P = 0.01). Hematoma rates were not increased in patients receiving acetylsalicylic acid (19% vs 16%, P = 0.62) or clopidogrel (25% vs 17%, P = 0.54). In a multivariate analysis, independent predictors of significant wound hematoma included postoperative LMWH (P = 0.001), a higher international normalized ratio on the day of surgery (P = 0.03), and male sex (P = 0.05). Conclusion: Elimination of postoperative LMWH was associated with a substantial reduction in hematoma rates following PM and ICD surgery.     

Intraosseous infusion — Emergency resuscitation in children

ABSTRACT: Intraosseous infusion provides a relatively safe, simple, rapid and therapeutically successful technique for the provision of fluids, blood, and parenteral medications to critically ill children. The article describes the history, physiology, technique, success and incidence of complications. This form of vascular access has particular application for paediatric resuscitation in rural Australia.     

Device‐Related Infection Among Patients With Pacemakers and Implantable Defibrillators: Incidence,Risk Factors,and Consequences

Risk Factors and Complications of Pacemaker and ICD Infection . Background: Device‐related infection is a major limitation of device therapy for cardiac arrhythmia. Methods: The authors analyzed the incidence and risk factors for cardiac device infection (CDI) among consecutive patients implanted with pacemaker (PM) or implantable cardioverter defibrillator (ICD) (including cardiac resynchronization therapy devices) at a tertiary health center in Hamilton, Ontario, Canada. Most patients with device‐related infections were identified by an internal infection control system that reports any positive wound and blood cultures following surgery, between 2005 and the present. A retrospective review of patient records was also performed for all patients who received an ICD or PM between July 1, 2003 and March 20, 2007. Results: A total of 24 infections were identified among 2,417 patients having device surgery (1%). Fifteen of these infections (60%) were diagnosed within 90 days of the last surgical procedure. Univariate analysis showed that patients presenting with CDI were more likely to have had a device replacement, rather than a new implant, had more complex devices (dual/triple chamber vs single), and were more likely to have had a prior lead dislodgement. Multivariate analysis found device replacement (P = 0.02) and cardiac resynchronization therapy (CRT)/dual‐chamber devices (P = 0.048) to be independent predictors of infection. One patient developed septic pulmonary emboli after having laser‐assisted lead extraction. No patient died and 22 patients received a new device. Conclusion: CDI occurs in about 1% of cases in high volume facilities. Pulse generator replacement surgery and dual‐ or triple‐chamber device implantation were associated with a significantly increased risk of infection. (J Cardiovasc Electrophysiol, Vol. pp. 786‐790, July 2010)     

Response complexity and precue interval effects on the lateralized readiness potential

Fundamental properties of an important new tool in cognitive electrophysiology, the lateralized readiness potential (LRP), were examined in two experiments. Experiment 1 resolved an apparent inconsistency in the literature by demonstrating that this response-specific lateralization is larger preceding complex then preceding simple finger movements. In Experiment 2, the foveally presented precue, which indicated hand of response, preceded the go/no-go stimulus by 0, 100, 300, or 1,400 ms. Analyses of LRP latency indicated that hand-specific preparation began earlier with longer foreperiods but was temporally linked to the reaction stimulus as well as the precue. Although the degree of lateralization did not predict reaction speed in either study, a nonlateralized, response-locked negativity was larger prior to faster reactions.