Temporary transvenous cardiac pacing: 6 years experience in one coronary care unit

Transcoronary pacing in an animal model : Second coated guidewire versus cutaneous patch as indifferent electrodes

BACKGROUND

Transcoronary pacing is a seldom used treatment option for unheralded bradycardias in the setting of percutaneous coronary interventions (PCI). In the present study we compared a coated guidewire inserted proximally into a coronary artery with a cutaneous patch electrode as indifferent electrodes for transcoronary pacing in a porcine model.

METHODS

Transcoronary pacing was investigated in 7 adult pigs in an animal catheterization laboratory. A standard guidewire insulated by a monorail-balloon was advanced into the periphery of a coronary artery serving as the cathode. As the indifferent anode, a special guidewire with electrical insulated by a polytetrafluoroethylene (PTFE) coating was positioned into the proximal part of the same coronary vessel. Transcoronary pacing parameters (threshold and impedance data and the magnitude of the epicardial electrogram) were compared with unipolar transcoronary pacing using a cutaneous patch electrode.

RESULTS

Transcoronary pacing was successful against both indifferent electrodes. Pacing thresholds obtained with the coated guidewire technique (1.8 ± 1.3 V) were similar to those obtained by standard unipolar transcoronary pacing with a cutaneous patch electrode (1.8 ± 1.5 V). The impedance with the additional coated guidewire was 419 ± 144 Ω and thereby slightly higher compared to 320 ± 103 Ω obtained by pacing against the patch electrode (p < 0.05). Both settings yielded comparable R‑wave amplitudes (8.0 ± 5.1 mV vs. 7.1 ± 3.6 mV).

CONCLUSIONS

A second coated guidewire is as effective as a cutaneous patch electrode when added as an indifferent electrode in transcoronary pacing. This transcoronary pacing technique could replace temporary transvenous pacing in emergency situations during PCI, especially when using the radial approach.

Is transjugular insertion of a temporary pacemaker a safe and effective approach?

Temporary pacemakers (TPMs) are usually inserted in an emergency situation. However, there are few reports available regarding which route of access is best or what the most preferred approach is currently in tertiary hospitals. This study aimed to compare procedure times, complication rates, and indications for temporary pacing between the transjugular and transfemoral approaches to TPM placement. We analyzed consecutive patients who underwent TPM placement. Indications; procedure times; and rates of complications including localized infection, any bleeding, and pacing wire repositioning rates were analyzed. A total of 732 patients (361 treated via the transjugular approach and 371 treated via the transfemoral approach) were included. Complete atrioventricular block was the most common cause of TPM placement in both groups, but sick sinus syndrome was especially common in the transjugular approach group. Separately, procedure time was significantly shorter in the transjugular approach group (9.0 ± 8.0 minutes vs. 11.9 ± 9.7 minutes; P < 0.001). Overall complication rates were not significantly different between the two groups, and longer duration of temporary pacing was a risk factor for repositioning. The risk of reposition was significantly increased when the temporary pacing was continued more than 5 days and 3 days in the transjugular approach group and the transfemoral approach group, respectively. The transjugular approach should be considered if the TPM is required for more than 3 days.

The initial U.S. experience with the Tempo active fixation temporary pacing lead in structural heart interventions

OBJECTIVES

This multicenter retrospective study of the initial U.S. experience evaluated the safety and efficacy of temporary cardiac pacing with the Tempo® Temporary Pacing Lead.

BACKGROUND

Despite increasing use of temporary cardiac pacing with the rapid growth of structural heart procedures, temporary pacing leads have not significantly improved. The Tempo lead is a new temporary pacing lead with a soft tip intended to minimize the risk of perforation and a novel active fixation mechanism designed to enhance lead stability.

METHODS

Data from 269 consecutive structural heart procedures were collected. Outcomes included device safety (absence of clinically significant cardiac perforation, new pericardial effusion, or sustained ventricular arrhythmia) and efficacy (clinically acceptable pacing thresholds with successful pace capture throughout the index procedure). Postprocedure practices and sustained lead performance were also analyzed.

RESULTS

The Tempo lead was successfully positioned in the right ventricle and achieved pacing in 264 of 269 patients (98.1%). Two patients (0.8%) experienced loss of pace capture. Procedural mean pace capture threshold (PCT) was 0.7 ± 0.8 mA. There were no clinically significant perforations, pericardial effusions, or sustained device-related arrhythmias. The Tempo lead was left in place postprocedure in 189 patients (71.6%) for mean duration of 43.3 ± 0.7 hr (range 2.5-221.3 hr) with final PCT of 0.84 ± 1.04 mA (n = 80). Of these patients, 84.1% mobilized out of bed with no lead dislodgment.

CONCLUSION

The Tempo lead is safe and effective for temporary cardiac pacing for structural heart procedures, provides stable peri and postprocedural pacing and allows mobilization of patients who require temporary pacing leads.

A comprehensive scoping review on transvenous temporary pacing therapy

Transvenous temporary cardiac pacing therapy (TV-TP) is widely used to treat life-threatening arrhythmias. Yet aggregated evidence on TV-TP is limited. We conducted a systematic scoping review to evaluate indications, access routes and complications of TV-TP, as well as permanent pacemaker therapy (PPM) following TV-TP. Clinical studies concerning TV-TP were identified in Ovid MEDLINE. Case studies and studies lacking complication rates were excluded. To assess complication incidence over time, differences in mean complication rates between 10-year intervals since the introduction of TV-TP were evaluated. We identified 1398 studies, of which 32 were included, effectively including 4546 patients. Indications varied considerably; however TV-TP was most commonly performed in atrioventricular block (62.7%). The preferred site of access was the femoral vein (47.2%). The mean complication rate was 36.7%, of which 10.2% were considered serious. The incidence of complications decreased significantly between 10-year interval groups, but remained high in the most recent time period (22.9%) (analysis of variance; p < 0.001). PPM was required in 64.2% of cases following TV-TP. Atrioventricular block was the primary indication for TV-TP; however indications varied widely. The femoral vein was the most frequent approach. Complications are common in patients undergoing TV-TP. Although a decrease has been observed since its introduction, the clinical burden remains significant. The majority of patients who underwent TV-TP required PPM therapy.

Epicardial pacemaker as a bridge for pacemaker-dependent patients undergoing explantation of infected cardiac implantable electronic devices

BACKGROUND AND AIM OF THE STUDY

Cardiac implantable electronic device (CIED) implantation is associated with an increase in CIED infection. For pacemaker-dependent patients, temporary pacemaker leads are implanted until infection remission, which allows new CIED implantation. We compared the outcome of pacemaker-dependent patients with infected CIED based on whether a combined single procedure of epicardial pacemaker implantation with system extraction or a temporary transjugular pacemaker implantation with interval system implantation was performed.

METHODS

This retrospective study included pacemaker-dependent patients with CIED infection who were divided into two groups: the Tempo and Epi groups. The Tempo group received temporary transvenous pacemaker connected to an external pulse generator. After infection remission, a new permanent pacemaker was implanted, and the temporary pacemaker leads were removed. The Epi group received implantable epicardial right-ventricular pacemaker through infrasternal inferior pericardiotomy, and a permanent pulse generator was implanted through the same incision between the subcutaneous tissue and abdominal fascia.

RESULTS

Sixty-six patients were included. Forty-two patients with epicardial pacemakers were discharged after 9.5 ± 8.8 days without infection of the newly implanted epicardial pacemaker. Patients with temporary transjugular pacemaker lead were discharged 23 ± 15 days after receiving permanent pacemakers. No serious complications were recorded in the Epi group.

CONCLUSIONS

CIED infections in pacemaker-dependent patients can be treated through epicardial pacemaker implantation that allows early patient mobility and reduces hospital stay with no risk of epicardial pacemaker infection. Epicardial pacemakers can be used as a bridge until permanent intravenous CIED is implanted or as a replacement for permeant intravenous CIED.

Transcoronary pacing : Reliability during myocardial ischemia and after implantation of a coronary stent

BACKGROUND

Transcoronary pacing is a useful therapeutic option for the treatment of unheralded bradycardias in the setting of percutaneous coronary interventions (PCI).

OBJECTIVES

In the present study, we investigated the influence of stent implantation and transient myocardial ischemia on the feasibility of transcoronary pacing in a porcine model.

METHODS

7 adult pigs underwent a percutaneous coronary intervention with implantation of a coronary stent under general anaesthesia in an animal catheterization laboratory. Transcoronary pacing was established by using a standard guidewire isolated with an angioplasty balloon positioned in the periphery of the right coronary artery serving as the cathode. As the indifferent anode, a skin patch electrode at the back of the animal was used. The reliability of transcoronary pacing was assessed by measurement of threshold and impedance data and the magnitude of the epicardial electrogram at baseline, after implantation of a coronary stent and finally during myocardial ischemia.

RESULTS

Effective transcoronary pacing could be demonstrated in all cases with the standard unipolar transcoronary pacing setup yielding a low pacing threshold at baseline of 1.3 ± 0.8 V with an impedance of 283 ± 67 Ω. Implantation of a coronary stent did not influence the pacing threshold (1.0 ± 0.4 V) and impedance (262 ± 63 Ω). Acute myocardial ischemia lead to a significant but clinically nonrelevant increase of the pacing threshold to 2.0 ± 0.6 V and a drop in pacing impedance (137 ± 39 Ω).

CONCLUSIONS

Transcoronary pacing in the animal model is not affected by implantation of a coronary stent in the same vessel used for pacing. Despite a significant increase in pacing threshold, the transcoronary pacing approach is reliable in acute myocardial ischemia during a percutaneous coronary intervention.

Outcomes of 4838 patients requiring temporary transvenous cardiac pacing: A statewide cohort study

BACKGROUND

Temporary-transvenous-cardiac-pacing (TTCP) is a potentially lifesaving procedure, however trends in its utilization and outcomes in unselected contemporary populations are all unknown.

METHODS

Consecutive patients requiring TTCP between July-1, 2000 and December-31, 2013 were identified from a statewide registry of admitted patients. In addition, all patients who underwent other cardiac procedures including permanent-pacemaker (PPM) implantation, automated-implantable-cardiac-defibrillator (AICD) implantation, percutaneous-coronary-intervention (PCI), or coronary-artery-bypass-graft (CABG) surgery were identified for comparative outcome analyses. Survival was tracked from a statewide death registry.

RESULTS

A total of 4838 patients (mean age [±standard deviation] 74.7 ± 12.7 years; 58.0% males) requiring TTCP were identified. The incidence for TTCP was 5.86 ± 1.06 cases per-100,000-persons-per-annum, declining by 46% between 2003 and 2013. During 4.2 ± 3.7 years of follow-up, 2594 (53.6%) patients died, of whom 569 (11.8%) died during the index admission. Weekend admission was associated with increased mortality compared to weekdays (hazard ratio: 1.15, 95% confidence interval [CI] 1.06-1.26, p = 0.002) and independently predicted all-cause death. After adjusting for age, gender, comorbidities, and referral source for admission, patients requiring TTCP had worse survival than those undergoing PPM (n = 17,988) or AICD (n = 5264) implantation, PCI (n = 46,859), or CABG surgery (n = 50,992) (adjusted hazard ratio [aHR]: 2.14, 95% CI 1.94-2.37; aHR: 1.61, 95% CI 1.41-1.83; aHR: 1.76, 95% CI 1.61-1.93; aHR: 2.09, 95% CI 1.98-2.21 respectively, all p < 0.001).

CONCLUSION

TTCP utilization is decreasing and is associated with substantial in-hospital and long-term mortality with weekend-weekday variation in outcome. Further studies are needed to develop strategies to better understand the determinants of adverse outcomes of these patients, as well as appropriate strategies for outcome improvement.

The double guidewire approach for transcoronary pacing in a porcine model

BACKGROUND

Transcoronary pacing is used for treatment of unheralded bradycardias in the setting of percutaneous coronary interventions (PCI).

OBJECTIVES

In the present study we introduced a new concept - the double guidewire approach - for transcoronary pacing in a porcine model.

METHODS

Transcoronary pacing was applied in 16 adult pigs under general anaesthesia in an animal catheterization laboratory. A special guidewire with electrical insulation by PTFE coating except for the distal part of the guidewire was positioned in the periphery of a coronary artery serving as the cathode. As the indifferent anode, an additional standard floppy tip guidewire was advanced into the proximal part of the same coronary vessel. The efficacy of double guidewire transcoronary pacing was assessed by measurement of threshold and impedance data and the magnitude of the epicardial electrogram compared with unipolar transcoronary pacing using a standard cutaneous patch electrode as indifferent anode.

RESULTS

Transcoronary pacing was effective in all cases. Pacing thresholds obtained with the double guidewire technique (1.5 ± 0.9 V) were similar to those obtained by standard unipolar transcoronary pacing with a cutaneous patch electrode (1.2 ± 0.7 V) and unipolar transvenous pacing against the same cutaneous patch electrode (1.5 ± 1.0 V). Bipolar transvenous pacing yielded the lowest pacing threshold at 0.8 ± 0.4 V.

CONCLUSIONS

Transcoronary pacing in the animal model with the novel "double guidewire approach" is a simple and effective pacing technique with comparable pacing thresholds obtained by standard unipolar transcoronary and transvenous pacing.

Echocardiography-guided versus fluoroscopy-guided temporary pacing in the emergency setting: an observational study

BACKGROUND

The insertion of a temporary pacemaker can be a lifesaving procedure in the emergency setting.

OBJECTIVES

This is an observational monocentric study comparing echocardiography-guided temporary pacemaker via the right internal jugular vein to standard fluoroscopy-guided temporary pacemaker via the femoral vein; the procedure was tested for noninferiority.

METHODS

Patients needing urgent pacing were consecutively enrolled. Primary efficacy endpoints were time to pacing and need for catheter replacement. Primary safety endpoint was a composite outcome of overall complications.

RESULTS

One hundred and six patients (77 ± 10 years) were enrolled: 53 underwent echocardiographic-guided and 53 fluoroscopy-guided temporary pacemaker. Baseline characteristics of the two groups of treatment were similar. Time to pacing was shorter in the echocardiography-guided than in the fluoroscopy-guided group (439 ± 179 vs. 716 ± 235 s; P<0.0001; power 100%). During the pacing (54 ± 35 h), there was a higher incidence of pacemaker malfunction in the fluoroscopy-guided group [15 vs. 3 patients; odds ratio (OR) 6.5, confidence interval (CI) 95% 1.9-29.7, P<0.001; power 5.7%] and there was a significantly lower incidence of complications in the echocardiography-guided temporary pacemaker group (6 vs. 22 patients; OR 0.18, CI 95% 0.06-0.49, P<0.001; echocardiography-guided temporary pacemaker events rate 0.1929 vs. fluoroscopy-guided temporary pacemaker events rate 1.398 per 100 person-hours paced, P<0.0001). In the standard group there was one death attributable to a temporary pacemaker complication (sepsis).

CONCLUSION

Echocardiography-guided temporary pacemaker is a well-tolerated procedure that could allow reliable insertion of a temporary pacemaker; therefore, it is a well-tolerated option in an emergency setting and in hospitals where fluoroscopy is not available.

Utility and safety of temporary pacing using active fixation leads and externalized re-usable permanent pacemakers after lead extraction

AIMS

After extraction of an infected cardiac implantable electronic device (CIED) in a pacemaker-dependent patient, a temporary pacemaker wire may be required for long periods during antibiotic treatment. Loss of capture and under sensing are commonly observed over time with temporary pacemaker wires, and patient mobility is restricted. The use of an externalized permanent active-fixation pacemaker lead connected to a permanent pacemaker generator for temporary pacing may be beneficial because of improved lead stability, and greater patient mobility and comfort. The aim of this study was to investigate the efficacy and safety of a temporary permanent pacemaker (TPPM) system in patients undergoing transvenous lead extraction due to CIED infection.

METHODS AND RESULTS

Of 47 patients who underwent lead extraction due to CIED infection over a 2-year period at our centre, 23 were pacemaker dependent and underwent TPPM implantation. A permanent pacemaker lead was implanted in the right ventricle via the internal jugular vein and connected to a TPPM generator, which was secured externally at the base of the neck. The TPPM was used for a mean of 19.4 ± 11.9 days (median 18 days, range 3-45 days), without loss of capture or sensing failure in any patient. Twelve of 23 patients were discharged home or to a nursing facility with the TPPM until completion of antibiotic treatment and re-implantation of a new permanent pacemaker.

CONCLUSION

External TPPMs are safe and effective in patients requiring long-term pacing after infected CIED removal.

Temporary cardiac pacemaker treatment in five Norwegian regional hospitals

OBJECTIVES

Over the last few decades the number of temporary pacemaker placements has declined, while the number of operators has increased. The present study was undertaken in order to assess the quality of present day temporary pacing in Norwegian general hospitals.

DESIGN

Prospective, multi-center study from five general hospitals in Norway with a catchment area of 998,000 inhabitants. All temporary pacing procedures performed at these hospitals during a 1-year period should be registered.

RESULTS

Fifty patients were treated with temporary pacing and six repeated procedures were performed due to pacing failure. The yearly procedure-rate was five per 100,000 inhabitants. Twenty-nine physicians were involved in these procedures, of whom five were experienced implanters, and 18 physicians participated in only one procedure each. Following temporary pacing a permanent pacemaker was implanted in 60% of patients. In-hospital mortality was 18%, and the incidence of bacteremia was 6%.

CONCLUSIONS

Temporary pacemaker treatment is currently performed with less than the required amount of skill, with a high number of complications. Cardiologists on call and the possibility of fast-track permanent implantation could improve the quality of care of patients with acute bradyarrhythmias.

Temporary Transvenous Cardiac Pacing in Patients With Acute Myocardial Infarction Predicts Increased Mortality

Background

Temporary pacemakers (TP) are used in emergency situations for severe bradyarrhythmias secondary to acute myocardial infarction (AMI) and to non-AMI related cardiac disorders. TP have been studied previously in AMI patients treated with thrombolytic therapy; limited information is available on current outcomes in AMI patients treated with percutaneous coronary intervention.

Methods

We reviewed the indications, complications, and mortality associated with TP insertion over a four year period (2003 - 2007) at a university hospital.

Results

Seventy-three temporary pacemakers were inserted (47 men, 26 women) during this period. The mean age was 65.2 years. TP were used in 29 AMI patients (39.7 % of total) and 44 non-AMI patients (60.3% of total). The duration of TP use was 2.6 ± 0.4 days in the whole cohort, 2.46 % of all AMI patients (29/1180) admitted during this period required a TP. Six of these patients requiring a TP required a permanent pacemaker. Eight patients with AMI and a TP died (27.6%). In contrast 8.9 % of AMI patients not requiring a TP died (P < 0.01). There were no statistically significant differences between the AMI and non-AMI groups in the duration of temporary pacing (2.4 ± 0.6 days vs. 2.8 ± 0.4 days), in complications (27.6% vs. 29.5%), or in mortality (27.6% vs. 15.9%). The need for a permanent pacemaker (PPM) differed significantly between the AMI and non-AMI patients (20.7% vs. 54.5%; P < 0.05).

Conclusion

Our results indicate that AMI patients infrequently require a TP and that approximately 20% of these patients require a PPM. These results suggest that early revascularization of the conduction system with current interventional techniques has decreased the need for TP in AMI patients. However, this group requires more intensive monitoring as the mortality rate in this group of patients is significantly higher than the other AMI patients not requiring TP.

[Efficacy and safety of non-permanent transvenous pacemaker implantation in an intensive care unit]

OBJECTIVE

To analyze the clinical indications for use, morbidity and mortality associated with a non-permanent transvenous pacemaker.

DESIGN

Prospective and observational study.

SETTING

Cardiac intensive care unit.

METHOD

One hundred and eighty-two patients with non-permanent pacemakers implanted consecutively over a period of four years.

DATA COLLECTED

Main variables of interest were demographic data, clinical indications, access route, length of stay and complications.

RESULTS

A total of 63% were men, with a median age of 78 ± 9.5 years and with symptomatic third-degree atrioventricular block in 76.9% of the cases. Femoral vein access was preferred in 92.3% of the cases. Complications appeared in 40.11% of the patients, the most frequent being hematoma at the site of vascular access (13.19%). Restlessness was associated to the need for repositioning the pacemaker due to a shift in the electrode (p=0.059) and to hematoma (p=0.07). Subclavian or jugular vein lead insertion (p=0.012; OR=0.16; 95%CI, 0.04-0.66), restlessness during admission to ICU (p=0.006; OR=3.2; 95%CI, 1.4-7.3), and the presence of cardiovascular risk factors (p=0.042; OR=5; 95%CI, 1.06-14.2) were identified by multivariate analysis as being predictors of complications. Length of stay in ICU was significantly longer when lead insertion was carried out by specialized staff (p=0.0001), and in the presence of complications (p=0.05).

CONCLUSIONS

Predictfurors of complications were restlessness, cardiovascular risk factors, and insertion through the jugular or subclavian vein. Complications prolonged ICU stay and were not related to the professionals involved.

A review of temporary cardiac pacing wires

AIMS

This review aims to tabulate data from all available studies of temporary cardiac pacing wires. Particular aims were to determine the best route of venous access and find ways to reduce complications. The review set out to see if specialist doctors are better at inserting wires than non-specialist doctors. In addition, a contemporary study of wire insertion has been performed to compare modern practice in the UK with the previous studies.

METHODS

A literature search produced 15 studies available for inclusion. Over 3700 patients from 1973 to 2004 were included. The data was tabulated and attention was given to the route of venous access, the complication rates and whether a specialist or non-specialist doctor had inserted the wire.

RESULTS

Internal jugular veins are associated with lowest complication rates and ease of access. Antecubital fossa veins have the highest complication rates. Complication rates are high, especially infections and failure to secure access. Specialist doctors have lower rates of complications than non-specialist doctors. Elderly patient suffer the highest complication rate. Our study showed comparable results to the previous studies.

CONCLUSION

Internal jugular veins are the preferred route for access followed by subclavian and femoral veins. The right side should be used when possible. The use of antibiotics and ultrasound probes must be contemplated for all wire insertions. Alternatives to wire insertion (especially in the elderly) must be seriously considered. Setting up an on-call rota would provide experienced doctors to reduce complication rates.

Percutaneous lead implantation connected to an external device in stimulation-dependent patients with systemic infection--a prospective and controlled study

BACKGROUND

Permanent pacemaker implantation usually is contraindicated in patients with systemic infection. The aim of the present study was to compare two different techniques of transvenous temporary pacing to bridge the infectious situation until permanent pacemaker implantation under infection-free conditions is possible.

METHODS AND RESULTS

Forty-nine patients with systemic infection and hemodynamic-relevant bradyarrhythmia/asystole were temporarily paced using either a conventional pacing wire/catheter (n = 26, reference group) or a permanent bipolar active pacing lead, which was placed transcutaneously in the right ventricle and connected to an external pacing generator (n = 23, external lead group). In both groups, there were no significant differences in patient characteristics. Whereas the sensing values were almost identical, the median pacing threshold was significantly higher in the reference group (1.0 V vs 0.6 V, P < 0.05). Within comparable duration of pacing (median: 8.2 vs 7.7 days), there were 24 pacing-related adverse events (including dislocation, resuscitation due to severe bradycardia, or local infection) in the reference group as compared to one event in the external lead group (P < 0.01). None of these complications resulted in cardiac death.

CONCLUSION

Thus, transvenous pacing with active fixation is safe and associated with a significantly lower rate of pacing-related adverse events as compared to the standard technique of transvenous pacing using a passive external pacing catheter.

Temporary transcoronary pacing by coated guidewires

Relevant bradycardias during percutaneous coronary intervention (PCI) are a rare event, but they require immediate therapy by temporary pacing. However, transvenous pacing is associated with frequent and severe complications. Therefore, we wanted to evaluate the safety and reliability of trans-coronary pacing by means of a PCI guidewire. Coronary pacing was applied to 70 consecutive patients undergoing PCI. Pacing was performed before and after PCI in a unipolar setting using standard guidewires as a cathode and a skin electrode as an anode. Both were connected to an external pacemaker. Coronary pacing (maximum output at 10 V, impulse duration 2.5 ms) was effective in 60 of 70 patients (85.7%). Successful pacing was achieved in the LAD and diagonal branches in 90% (27 of 30 Pts.), in the LCX and marginal branches 84.2% (16 of 19 Pts.) and in the RCA in 81% (17 of 21 Pts.). Pacing thresholds were comparable in all vessels within a range of 1-10 V averaging 6.6 +/- 2.3 V before and 6.6 +/- 2.2 V after PCI. The impedance ranged from 190-544 Omega with mean pacing impedance for coronary pacing of 424 Omega before and 416 Omega after PCI, respectively. Significant bradycardias during PCI occurred in 7 cases (10%). In three cases (4.3%) temporary coronary pacing became necessary at a maximum pacing duration of 3 min. There were no severe side effects. Coronary spasm occurred in 3 cases (4.3%) after pacing and was promptly reversible after intracoronary application of nitroglycerine. It is concluded that coronary pacing is a safe and feasible method for the treatment of bradycardias during PCI. It avoids additional venous puncture under hemodynamically unstable conditions and subsequent transvenous pacing, which is accompanied by potentially severe complications and additional costs.

Temporary Pacemakers in Critically Ill Patients

Temporary cardiac pacing provides electrical stimulation to a heart compromised by disturbances in the conduction system causing hemodynamic instability. The use of a temporary pacemaker to treat a bradydysrhythmia or in some cases, a tachydysryhthmia, is undertaken when the condition is temporary and a permanent pacemaker is not necessary or available in a timely fashion. Temporary cardiac pacing is utilized in acute situations and for critically ill patient populations requiring immediate therapy. This article discusses the various indications and contraindications to temporary cardiac pacing therapy, reviews the different modalities of temporary pacemakers, and outlines critical considerations in the management of patients being treated with a temporary pacemaker.

Temporary transvenous pacing with an active fixation bipolar lead in children: a preliminary report

Various techniques and electrode catheters have been developed for effective and safe temporary transvenous cardiac pacing. In neonates and children, lead dislodgment and myocardial perforation have been attendant risks with passive fixation leads. We report our experience with the recently introduced Medtronic 6416 active fixation bipolar lead in a small group of children. Between January 2000 and February 2002, 4 children (2 boys, 2 girls) underwent temporary transvenous pacing with the Medtronic 6416 lead. The median age at implantation was 4.25 years (range: 5 days-13 years), median weight was 14.5 kg (range: 2.5 kg-54 kg) and the median duration of temporary pacing was 19.5 days (range: 5-38 days). The indication for temporary pacing was AV block (n = 2), sinus arrest (n = 1) and sinus node dysfunction (n = 1). The acute pacing threshold was <1.5 mA with no significant rise in the follow-up period. The venous access for lead placement was femoral vein (n = 2), internal jugular vein (n = 1), and subclavian vein (n = 1). There were no complications related to implantation or in the follow-up period. The Medtronic 6416 lead appears to be a safe and effective tool in temporary transvenous pacing in neonates and children.

Complete heart block and polymorphic ventricular tachycardia complicating myocardial infarction after occlusion of the first septal perforator with coronary stenting

We report a case of complete heart block (CHB) and polymorphic ventricular tachycardia (VT) which was associated with a modest-sized myocardial infarction (MI) following incidental occlusion of the first septal perforator (FSP) branch after stent deployment to the left anterior descending (LAD) coronary artery. These complications were successfully treated with temporary pacing and subsequently resolved with spontaneous recanalization of the first septal perforator. This case represents an interesting product of medical progress which defies the adverse natural history and poor prognosis of anteroseptal MI associated with CHB due to the small amount of myonecrosis associated with this event.

An audit of cardiac pacing in the elderly: effect of myocardial infarction on outcome

OBJECTIVE

To audit the outcome of temporary endocardial pacing in an elderly population.

DESIGN

Retrospective case-series analysis.

SETTING

The Department of Medicine for the Elderly at the Wrexham Maelor Hospital, a District General Hospital with 612 beds serving a catchment population of 220,000.

SUBJECTS

A sample of 50 consecutive elderly patients, with an age range of 65 to 99 years, undergoing transvenous cardiac pacing.

MAIN OUTCOME MEASURES

Length of stay in hospital, complications of the pacing procedure, whether a permanent pacemaker was installed, and whether the patient died within 1 month of admission.

RESULTS

There was no difference in length of stay between those with a myocardial infarction and those without. Minor complications occurred in three patients (one local infection and two "failures to pace"). Major complications occurred in two patients (septicemia and pneumonia). More patients without a myocardial infarction (86.9%) went on to implantation of a permanent pacemaker than those with an infarction (11.1%, P = 0.001), and fewer of them died (8.7% compared with 48.1%, P = 0.0025). In those patients with a myocardial infarction who died, there was no difference between the proportions who had inferior (7/18) and anterior (5/9) infarctions.

CONCLUSION

Cardiac pacing seems to be a safe and reliable procedure in the elderly, although long term morbidity and mortality may be dependent on the presence or absence of myocardial ischaemic disease. Myocardial infarction in the elderly is an event of major significance, carrying with it a high mortality rate, particularly if accompanied by cardiogenic shock and the need for cardiac pacing.

Hemodynamic effects of different temporary pacing modes for the management of bradycardias complicating acute myocardial infarction

Twelve patients requiring temporary pacing following acute myocardial infarction (AMI) (10 heart block, 2 junctional bradycardia) had hemodynamic measurements taken with ventricular demand pacing at 80 ppm (VVI80), ventricular demand pacing at the atrial rate (VVIa), physiological pacing (DDD), and spontaneous (intrinsic) rhythm. VVI80 mode did not improve any hemodynamic parameter compared with spontaneous rhythm. VVIa mode improved diastolic and mean arterial pressures only. DDD mode improved most hemodynamic parameters compared with spontaneous rhythm (cardiac output by 29% [P less than 0.0001]; blood pressure: diastolic by 24% [P less than 0.01], systolic by 19% [P less than 0.01], mean by 21% [P less than 0.005]; pulmonary wedge pressure by 10% [P = 0.057] and right atrial pressure by 24% [P less than 0.005]) and also significantly improved some parameters compared with VVIa (cardiac output by 20% [P less than 0.001], systolic blood pressure by 11% [P less than 0.01] and right atrial pressure by 15% [P less than 0.01]). Physiological pacing is hemodynamically superior both to ventricular pacing and spontaneous rhythm for patients requiring temporary pacing following AMI. Ventricular pacing at 80 ppm has little hemodynamic advantage over spontaneous rhythm.