Permanent Pacemaker Insertion 

Updated: Apr 29, 2021
Author: Chakri Yarlagadda, MD, FACC, FSCAI, FASNC, CCDS; Chief Editor: Richard A Lange, MD, MBA 



Permanent pacemaker insertion plays a key role in the management of heart rhythm disorders and heart failure.[1] The number of permanent pacemaker insertions in the United States has been steadily increasing.[2] A pacemaker is an electronic device, approximately the size of a pocket watch, that senses intrinsic heart rhythms and provides electrical stimulation when indicated.

At present, three approaches to permanent cardiac pacing are in common use:

  • Single-chamber pacemaker – With this device, one pacing lead is implanted in the right atrium or ventricle

  • Dual-chamber pacemaker – With this device, two pacing leads are implanted (one in the right ventricle and one in the right atrium); this is the most common type of implanted pacemaker

  • Biventricular pacing (cardiac resynchronization therapy [CRT]) – With this approach, in addition to single- or dual-chamber right heart pacing leads, a lead is advanced to the coronary sinus for left ventricular epicardial pacing

The first implantable pacemaker to be used in a human being was inserted by Dr. Ake Senning in 1958; it lasted for only a few hours. Since then, cardiac pacing has evolved to include single-chamber, dual-chamber, and CRT devices. Epicardial lead implantation by thoracotomy has largely been replaced by transvenous placement of right atrial and right ventricular leads, as well as left ventricular epicardial pacing lead placement via the coronary sinus.

Remarkable advances have been made in pacemaker technology, including reduced size, increased battery longevity, and remote monitoring capability, as well as the addition of magnetic resonance imaging (MRI)-safe pacemakers.[3]

Published guidelines that outline indications for cardiac pacing are available from both the American Heart Association (AHA) and the European Society of Cardiology.[4, 5] This article outlines the clinical indications for pacing, implant techniques, and common pacing system complications.


Indications for pacemaker implantation are categorized into the following classes[6] :

  • Class I – These are conditions where implantation of a pacemaker is considered necessary and beneficial (benefits much greater than risks).

  • Class II – These are conditions where placement is indicated, but there is conflicting evidence or divergence of opinion. In Class IIa weight of evidence is in favor of efficacy (benefits greater than risk), while in class IIb, the efficacy is less well established (benefits greater than or equal to the risks).

  • Class III – These are conditions in which permanent pacing is not recommended, and in some cases, it may be harmful (risks greater than the benefits).

The most common indications for permanent pacemaker implantation are sinus node dysfunction and high-grade atrioventricular block.[6]

In 2008, the American College of Cardiology (ACC), the AHA, and the Heart Rhythm Society (HRS) jointly published guidelines for pacemaker implantation.[7] For further details on the following indications, see ACC/AHA/HRS 2008 Guidelines for Device-Based Therapy of Cardiac Rhythm Abnormalities.

Sinus node dysfunction

Class I indications include the following:

  • Documented symptomatic sinus bradycardia including frequent sinus pauses which produce symptoms and symptomatic sinus bradycardia that results from required drug therapy for medical condition

  • Symptomatic chronotropic incompetence (failure to achieve 85% of age-predicted maximal heart rate during formal or informal stress test or inability to mount age appropriate heart rate during activities of daily living)

Class II indications include the following:

  • Sinus bradycardia with heart rate less than 40 bpm, but no clear association between the symptoms and bradycardia

  • Unexplained syncope when clinically significant abnormalities of sinus node function are discovered or provoked in electrophysiological (EP) studies

  • Minimally symptomatic patients with chronic heart rate less than 40 bpm while awake

Acquired atrioventricular (AV) block

Class I indications include the following:

  • Complete third-degree AV block with or without symptoms

  • Symptomatic second degree AV block, Mobitz type I and II

  • Exercise-induced second or third degree AV block in the absence of myocardial infarction

  • Mobitz II with widened QRS complex

Class II indications include the following:

  • Asymptomatic Mobitz type II with the narrow QRS complex

  • First degree AV block when there is a hemodynamic compromise

  • Asymptomatic second degree AV block at Intra or Infra-His levels found in EP studies

Chronic bifascicular block​

Class I indications include the following:

  • Advanced second-degree AV block or intermittent third-degree AV block

  • Alternating bundle-branch block

  • Type II second-degree AV block

Class II indications include the following:

  • In patients having syncope not demonstrated to be due to AV block when other likely causes have been excluded, specifically ventricular tachycardia (VT)

  • Incidental finding at EP study of a markedly prolonged HV interval (greater than 100 ms) or pacing-induced infra-His block in asymptomatic patients. (HV interval is conduction time from the His bundle which is located just below the AV node to first identifiable onset of ventricular activation)

  • Can be considered in patients with neuromuscular disease such as myotonic muscular dystrophy, Erb dystrophy and peroneal muscular dystrophy with bifascicular block or any fascicular block, with or without symptoms

After acute phase of myocardial infarction

Class I indications include the following:

  • Permanent ventricular pacing for persistent second degree AV block in the His-Purkinje system with alternating bundle branch block or third degree AV block within or below the His-Purkinje system after ST-segment elevation MI (STEMI)

  • Permanent ventricular pacing for a transient advanced second or third-degree infranodal AV block and associated bundle branch block

  • Permanent ventricular pacing for persistent and symptomatic second or third degree AV

Class II indications include the following:

  • Permanent ventricular pacing may be considered for the asymptomatic persistent second or third degree AV block at AV node level

Neurocardiogenic syncope and hypersensitive carotid sinus syndrome

Class I indications include the following:

  • Recurrent syncope caused by spontaneously occurring carotid sinus stimulation and carotid sinus pressure that induces ventricular asystole of more than 3 seconds

Class II indications include the following:

  • Reasonable in patients having syncope without clear and provocative event, and with a hypersensitive cardio-inhibitory response of 3 seconds or longer

  • Can be considered for significantly symptomatic neurocardiogenic syncope associated with bradycardia documented spontaneously or at the time of tilt-table testing

Hypertrophic cardiomyopathy (HCM)

Class I indications include the following:

  • Patients with HCM having sinus node dysfunction and AV block

Class II indications include the following:

  • Can be considered in medically refractory symptomatic patients with HCM and with significant resting or provoked left ventricular outflow tract obstruction

Congenital heart disease

Class I indications include the following:

  • For advanced second or third-degree AV block associated with symptomatic bradycardia, ventricular dysfunction, or low cardiac output; also for advanced second or third-degree AV block which is not expected to resolve or persists for 7 days or longer after cardiac surgery

  • For sinus node dysfunction with a correlation of symptoms during age inappropriate bradycardia

  • Congenital third-degree AV block with a wide QRS escape rhythm, complex ventricular ectopy or ventricular dysfunction

  • Congenital third-degree AV block in an infant with a ventricular rate < 55 bpm or with congenital heart disease with a ventricular rate of < 70 bpm

Class II indications include the following:

  • For patients with congenital heart disease and sinus bradycardia for the prevention of recurrent episodes of intra-atrial re-entrant tachycardia; sinus node dysfunction may be intrinsic or secondary to antiarrhythmic treatment

  • For congenital third-degree AV block beyond the first year of life with an average heart rate < 50 bpm, abrupt pauses in ventricular rate which are 2 or 3 times the basic cycle length, or associated with symptoms due to chronotropic incompetence

  • May be considered for transient postoperative third-degree AV block that reverts to sinus rhythm with the residual bifascicular block

  • Considered for asymptomatic sinus bradycardia after biventricular repair of congenital heart disease in patients with a resting heart rate < 40 bpm or with pauses in ventricular rate longer than 3 seconds


Contraindications for permanent pacemaker insertion include the following:

  • Local infection at implantation site

  • Active systemic infection with bacteremia

  • Severe bleeding tendencies (relative contraindication)

  • Active anticoagulation therapy (relative contraindication)

  • Severe lung disease and positive end-expiratory pressure ventilation (relative contraindication for internal jugular and subclavian access)

Technical Considerations

Procedural planning

Cardiac pacing can be either temporary or permanent. Temporary pacing may be accomplished transcutaneously (ie, placing two external pacing pads over the chest wall in the anteroposterior or anterolateral location) or via transvenous placement of a temporary pacing wire in one or more of the right heart chambers. In a patient who has recently undergone cardiac surgery, temporary epicardial leads are often placed and removed before the patient is discharged from the hospital.[8]

Permanent pacing is most commonly accomplished through transvenous placement of leads to the endocardium (ie, right atrium or ventricle) or epicardium (ie, to the left ventricular surface via the coronary sinus), which are subsequently connected to a pacing generator placed subcutaneously in the infraclavicular region. In a patient without appropriate venous access, epicardial leads can be placed via a thoracotomy and tunneled subcutaneously to the pacing generator. Recently, a leadless permanent pacemaker lead (Micra, Medtronic Inc) has been approved as an alternative to conventional transvenous pacemakers.

Complication prevention

Multiple studies have shown that infection rates can be reduced by employing maximal sterile-barrier precautions, including mask, cap, sterile gown, sterile gloves, and large sterile drape.

Subclavian artery injury may occur during subclavian vein access, carotid artery puncture during jugular vein access, and femoral artery puncture during femoral vein access. The subclavian artery cannot be compressed; accordingly, the subclavian approach should be avoided in anticoagulated patients.

An air embolism may be caused by negative intrathoracic pressure during inspiration by the patient, which sucks air into an open line hub. Hence, line hubs should always be occluded. Placing the patient in the Trendelenburg position lowers the risk of this complication.

If air embolism occurs, the patient should be placed in the Trendelenburg position with a left lateral decubitus tilt; this may prevent the movement of air into the right ventricle and onward into the pulmonary artery. In addition, 100% oxygen should be administered to speed resorption of the air. If a catheter is located in the heart, aspiration of the air should be attempted.

Dysrhythmia due to mechanical irritation of the heart by the wire or catheter tip may occur. It can usually be terminated by simply withdrawing the equipment into the superior vena cava. Placing a central venous catheter without a cardiac monitor is unwise.

If the clinician is not conscientious about maintaining control of the guide wire, it may be inadvertently inserted fully into the vein and have to be retrieved.

Patients who are allergic to antibiotics may experience anaphylaxis upon insertion of an antibiotic-impregnated catheter.


A 2016 retrospective, observational study evaluated the long-term (1 year) utility of permanent pacemakers implanted early (≤30 days) in 247 patients with complete heart block after cardiac surgery.[9] By determining the frequency of ventricular pacemaker at each pacemaker interrogation visit, investigators found that most permanent pacemakers were not underutilized, and there was no association between longer delay from surgery to implantation of the device and a higher likelihood that there would long-term use of the permanent pacemaker.[9]

In another 2016 retrospective study (1984-2002; followed to 2014) comprising data from 995 consecutive patients who underwent dual-chamber (DDD) pacemaker implantation and had at least one follow-up visit, investigators reported an association between sex and indications to DDD pacing therapy.[10] ​ Although the rate of adverse events was similar between the sexes, women had significantly more incidences of sick sinus syndrome, a history of paroxysmal atrial fibrillation, and a similar percentage of atrioventricular block. Women also had significantly longer duration of follow-up despite markedly older age at implantation than men.[10]

Observational data (2001-2011) from the Spanish ARIAM registry (Analysis of Delay in AMI [acute myocardial infarction]) of 27,608 patients with acute coronary syndrome (ACS) found that in 62 of these patients who received permanent pacemakers, implantation of these devices was independently associated with death.[11] Other factors independently associated with permanent pacemaker implantation in the setting of ACS included older age, heart failure, arrhythmias, and left bundle branch block at admission to the intensive care unit.


Periprocedural Care


Equipment required for permanent pacemaker insertion includes the following:

  • Fluoroscope

  • Instrument tray

  • Pacing system analyzer

  • Introducer kit

  • 1-2% lidocaine or bupivacaine

  • Antimicrobial flush and saline for pocket irrigation

  • Emergency crash cart with medications

  • Battery or electric cautery

  • Suture material

  • External pacemaker/defibrillator

Fluoroscopy and electrocardiography (ECG) are essential. Single-plane fluoroscopy using anteroposterior, 30° right anterior oblique, and 45° left anterior oblique views usually suffices for transvenous implantation from either the right or the left pectoral approach. High-resolution digital C-arm fluoroscopy is generally needed for implants performed in the operating room (OR). Currently, initial lead sensing and capture measurements are obtained by system analyzers, which may be freestanding or built into the pacer programmer.

Instrument requirements vary with surgical preferences. A minivascular tray from the OR provides an excellent starting point and can be modified as needed. Suture materials include both nonabsorbable material for lead and device anchoring and absorbable material for pocket closure. Antimicrobial flush and saline for pocket irrigation should be available. If phlebography is to be performed, an appropriate intravenous (IV) contrast agent must be available.


Although transvenous pacemaker leads from different manufacturers vary significantly, they can be classified into one of two types on the basis of the fixation mechanism at the tip:

  • Active fixation with a screw

  • Passive fixation with tines

The pacemaker battery usually lasts about 6-12 years, depending on type, programming, frequency of use, and lead characteristics. When the battery is depleted, the pulse generator must be replaced. The previously placed leads can be used if they are functioning properly.

Current pacemakers are programmable to different modes. A standardized code for pacemaker nomenclature was developed jointly by the North American Society of Pacing and Electrophysiology (NASPE—the older name for what is now the HRS) and the British Pacing and Electrophysiology Group (BPEG).[12] The code has five positions, each of which denotes a function of the lead in the cardiac chamber; letter values are assigned to the positions (see the Table below). The fifth position is not widely used in current practice.

Table. Standardized Code for Pacemaker Nomenclature (Open Table in a new window)






Chamber(s) paced

Chamber(s) sensed

Response to sensing

Rate modulation

Multisite pacing

O = None

O = None

O = None

O = None

O = None

A = Atrium

A = Atrium

T = Triggered

R = Rate modulation

A = Atrium

V = Ventricle

V = Ventricle

I = Inhibited


V = Ventricle

D = Dual (A+V)

D = Dual (A+V)

D = Dual (T+I)


D = Dual (A+V)

Patient Preparation


Implantation of pacing systems usually involves a combination of local anesthesia and conscious sedation. Infiltration of skin and subcutaneous tissue at the implant site with 1-2% lidocaine or bupivacaine provides sufficient local anesthesia for the majority of implant procedures. Conscious sedation may be administered in the form of carefully titrated IV midazolam and fentanyl by trained and qualified personnel. On rare occasions, general anesthesia may be required in an extremely uncooperative or high-risk patient.


The patient is usually positioned on his or her back, with the arms tucked. If air embolism occurs, the patient should be placed in the Trendelenburg position with a left lateral decubitus tilt; this may prevent the movement of air into the right ventricle and onward into the pulmonary artery.

Monitoring and Follow-Up

Patients should plan to have someone drive them home after discharge.

Routine oral antibiotics should be continued for 3-10 days after the time of discharge. Discharge medications must be optimized after pacemaker implantation, especially atrioventricular blocking medications.

The method and frequency of pacemaker checkup are determined by the physician involved in pacemaker follow-up care and are based on the individual patient’s needs, the type of pacemaker used, and any underlying medical conditions present.

Medicare-allowed pacemaker checks are as follows:

  • Single-chamber pacemakers - 2 pacemaker checks in the first 6 months after insertion, then 1 every 12 months or during any pacer malfunction

  • Dual-chamber pacemakers - 2 pacemaker checks in the first 6 months after insertion, then 1 every 6 months or during any pacer malfunction

There is a 90-day global period for pacemaker insertion; as a rule, any pacer checks during that time are included in the global period.

Pacemakers can be followed via transtelephonic monitoring or remotely via wireless technology. Although these technologies provide some comfort to the patient, they offer only limited interrogation data and pacemaker information to the monitoring physician. One of the disadvantages of remote monitoring is that it does not permit programming or changes to the pacemaker.



Approach Considerations

Permanent pacemaker insertion is considered a minimally invasive procedure. Transvenous access to the heart chambers under local anesthesia is the favored technique, most commonly via the subclavian vein, the cephalic vein, or (rarely) the internal jugular vein or the femoral vein. The procedure is typically performed in a cardiac catheterization laboratory or in an operating room (OR).

The pacing generator is typically placed subcutaneously in the infraclavicular region. Occasionally, pacemaker leads are implanted surgically via a thoracotomy, and the pacing generator is placed in the abdominal area. Single-chamber and dual-chamber pacer insertion can be accomplished from either left or right pectoral sites. After appropriate sedation, the chest is prepared with an antiseptic solution, and the area is covered with sterile drapes to keep the incision area as clean as possible.

In current practice, antibiotic prophylaxis is standard for device implantation. Preoperative antibiotic use reduces the risk of pacemaker-related infections by approximately 80%.[13, 14]

Implantation of Pacemaker

Routinely, cefazolin 1 g or patient weight-based dosing is administered intravenously (IV) 1 hour before the procedure. If the patient is allergic to penicillins or cephalosporins, vancomycin 1 g IV or another appropriate antibiotic may be administered preoperatively.

Venous access

A central vein (ie, the subclavian or axillary vein) is accessed via a percutaneous approach. In patients in whom this is technically difficult because skeletal landmarks are deviated, an initial brief fluoroscopic examination will greatly reduce the time and complications associated with obtaining the access.

The subclavian vein is typically accessed at the junction of the first rib and the clavicle. On occasion, phlebography may be required to visualize the vein adequately or to confirm its patency. Some centers employ the first rib approach under fluoroscopy, with no or minimal incidence of pneumothorax.

After venous access is obtained, a guide wire is advanced through the access needle, and the tip of the guide wire is positioned in the right atrium or the vena caval area under fluoroscopy. The needle is then withdrawn, leaving the guide wire in place. If indicated, a second access will be obtained in a similar fashion for positioning of a second guide wire.

Sometimes, a double-wire technique is used, whereby 2 guide wires are inserted through the first sheath and the sheath then withdrawn, so that 2 separate sheaths can be advanced over the 2 guide wires. This technique can cause some resistance or friction during sheath or lead advancement.

Creation of pocket

A 1.5- to 2-inch incision is made in the infraclavicular area parallel to the middle third of the clavicle, and a subcutaneous pocket is created with sharp and blunt dissection where the pacemaker generator will be implanted. Some physicians prefer to make the pocket first and obtain access later through the pocket or via venous cutdown; once access is obtained, they position the guide wires as described above.

Placement of lead(s)

Over the guide wire, a special peel-away sheath and dilator are advanced. The guide wire and dilator are withdrawn, leaving the sheath in place. A stylet (a thin wire) is inserted inside the center channel of the pacemaker lead to make it more rigid, and the lead-stylet combination is then inserted into the sheath and advanced under fluoroscopy to the appropriate heart chamber. Usually, the ventricular lead is positioned before the atrial lead to prevent its dislodgment.

Making a small curve at the tip of the stylet renders the ventricular lead tip more maneuverable, so that it can more easily be placed across the tricuspid valve and positioned at the right ventricular apex or septum. Techniques for positioning the ventricular lead have been described.[15, 16]

Once correct lead positioning is confirmed, the lead is affixed to the endocardium either passively with tines (like a grappling hook) or actively via a helical screw located at the tip. The screw at the tip of the pacemaker is extended or retracted by turning the outer end of the lead with the help of a torque device. Adequate extension of the screw is confirmed with fluoroscopy. Each manufacturer has its own proprietary identification marks for confirming adequate extension of the screw.

Once the lead is secured in position, the introducing sheath is carefully peeled away, leaving the lead in place. After the pacing lead stylet is removed, pacing and sensing thresholds and lead impedances are measured with a pacing system analyzer, and pacing is performed at 10 V to make sure that it is not causing diaphragmatic stimulation. After confirmation of lead position and thresholds, the proximal end of the lead is secured to the underlying tissue (ie, pectoralis) with a nonabsorbable suture that is sewn to a sleeve located on the lead.

If a second lead is indicated, it is positioned in the right atrium via a second sheath, with the lead tip typically positioned in the right atrial appendage with the help of a preformed J-shaped stylet.

In a patient who is without an atrial appendage as a result of previous cardiac surgery, the lead can be positioned medially or in the lateral free wall of the right atrium. As with the ventricular lead, the atrial lead position is confirmed, impedance is assessed, the stylet is withdrawn, and the lead is secured to the underlying pectoralis with a nonabsorbable suture.

Positioning of pulse generator

When the leads have been properly positioned and tested and sutured to the underlying tissue, the pacemaker pocket is irrigated with antimicrobial solution, and the pulse generator is connected securely to the leads. Many physicians secure the pulse generator to underlying tissue with a nonabsorbable suture to prevent migration or twiddler syndrome.

Typically, the pacemaker is positioned superficial to the pectoralis, but occasionally, a subpectoral or inframammary position is required. After hemostasis is confirmed, a final look under fluoroscopy before closure of the incision is recommended to confirm appropriate lead positioning.

Completion and closure

The incision is closed in layers with absorbable sutures and adhesive strips. Sterile dressing is applied to the incision surface. An arm restraint or immobilizer is applied to the unilateral arm for 12-24 hours to limit movement.

A postoperative chest radiograph is usually obtained to confirm lead position and rule out pneumothorax. Before discharge on the following day, posteroanterior and lateral chest radiographs will be ordered again to confirm lead positions and exclude delayed pneumothorax.

Pain levels are typically low after the procedure, and the patient can be given pain medication to manage breakthrough pain associated with the incision site.


Access-related complications

Early access-related complications include the following:

  • Bleeding

  • Hematoma

  • Phlebitis or thrombophlebitis of the vein

  • Local infection

  • Arterial injury or puncture

  • Hemothorax

  • Pneumothorax

  • Catheter-related thrombosis (which may lead to pulmonary embolism)

  • Air embolism

  • Dysrhythmias

  • Atrial wall puncture from guide wire (which may lead to pericardial tamponade)

  • Lost guide wire

  • Anaphylaxis

  • Chylothorax (possible with left-side lead insertion)

A study by Armaganijan et al reported that age is a factor in early postimplant complications, with elderly patients (older than 75 years) having an increased risk of pneumothorax and both atrial and ventricular lead dislodgement/loss of capture.[17]

Late access-related complications include the following:

  • Chylothorax

  • Hematoma

  • Venous thrombosis or occlusion

  • Phlebitis

  • Atrioventricular fistula

  • Hemothorax

  • Infection

Pocket-related complications

Early pocket-related complications include the following:

  • Swelling

  • Hematoma

  • Bruising and local pain

  • Infection

Late pocket-related complications include the following:

  • Pocket erosion

  • Pocket infection

  • Chronic pain at the site

Lead-related complications

Early lead-related complications include the following:

  • Atrial or ventricular arrhythmias

  • Chamber perforation[18]

  • Pneumothorax and pneumopericardium (with an atrial lead)

  • Intercostal or diaphragm pacing

  • Pectoral muscle stimulation

  • Lead dislodgement

  • Tricuspid valve laceration

  • Cardiac tamponade

  • Pericardial friction rub

  • Hypotension

  • Bleeding

Late lead-related complications include the following:

  • Infection of pacer lead

  • Endocarditis

  • Systemic infection

  • Perforation

  • Access vein thrombosis

  • Inferior vena cava thrombus

  • Pectoral muscle stimulation

  • Right atrial thrombus

  • Loss of capture and sensing

  • Tricuspid regurgitation (also independently associated with body mass index >30 kg/m2[19] )

  • Lead fracture

  • Intercostal or diaphragm pacing

Pacemaker generator–related complications

Early pacemaker generator – related complications include the following:

  • Infection

  • Malfunction, including undersensing, oversensing, loss of capture, loss of output, inappropriate rate, inappropriate mode, pulse generator failure, pacemaker-mediated tachycardia, and pacemaker syndrome[20]

Late pacemaker generator – related complications include the following:

  • Twiddler syndrome

  • Pacemaker infection

  • Pacer malfunction[20]

  • Allergy or sensitivity to the device materials

Pacemaker device infection

Cardiac device infections can lead to longer hospital stays, increased costs, and higher mortalities. If they are detected and treated at an early stage, device extraction may be avoided and patient morbidity and mortality significantly reduced.

Pacemaker infections may be divided into 2 general types on the basis of the initial source of infection:

  • Primary infections - The device or pocket itself is the source of infection, usually because of contamination at the time of implantation

  • Secondary infection - The leads, device, and the pocket are seeded by bacteremia derived from a different source

Overall device infection rates range from 0.68-2.2%.[21, 22, 23, 24, 25] Independent risk factors for cardiac device infection have been identified. These include the following:

  • Pulse generator replacement

  • Dual- or triple-chamber device implantation[22]

  • Advanced patient age (older than 60 years)[25]

  • Renal dysfunction

  • Oral anticoagulation[24]

Complete device system extraction (either percutaneously or intraoperatively), antimicrobial therapy of appropriate duration, and reimplantation of a new pacing system at a different site are the current methods of treatment for device infection. Implantation of a leadless permanent pacemaker lead (Micra, Medtronic Inc) may be preferable in some infected patients. The majority of patients discharged after such treatment will be free of infection.[26]

Other complications

The patient may experience reactions to either a local anesthetic or an IV sedative. Radiation skin burns have been reported to occur as a result of prolonged fluoroscopy in technically difficult cases.

Cardiac Resynchronization Therapy

Cardiac resynchronization therapy (CRT), also referred to as biventricular pacing or multisite ventricular pacing, is a component of modern heart failure therapy for qualified patients. In CRT, there is a coronary sinus lead for left ventricular epicardial pacing in addition to a conventional right ventricular endocardial lead. By simultaneously pacing the right and left ventricles, CRT reduces the ventricular dyssynchrony that is frequently present in patients with ventricular dilatation or conduction system defect.

CRT can involve either solely pacing (CRT-P) or also include the potential for defibrillation (CRT-D). The following discussion focuses on CRT-P.

CRT is recommended for patients with a left ventricular ejection fraction < 35%, a QRS duration longer than 120 msec, sinus rhythm, and New York Heart Association (NYHA) functional class III or ambulatory class IV heart failure symptoms with optimal medical therapy.[7] Trials suggest that CRT may also reduce morbidity and mortality in patients with mildly symptomatic heart failure. Consequently, the 2010 European guidelines and updated 2012 ACC/AHA/HRS guidelines now recommend CRT for the NYHA class II patient population.[27, 28] The ACC/AHA/HRS guidelines also now indicate CRT for patients with left-bundle-branch block with a QRS duration that is greater than or equal to >150 msec.[28]

Biventricular pacing has been effective in improving symptoms and quality of life, reducing heart failure hospitalizations, and reducing mortality because of its ability to achieve the following results:

  • Reduction in ventricular electromechanical delay

  • Improved ventricular function

  • Reduced metabolic demands

  • Improved functional mitral regurgitation

  • Favorable ventricular remodeling

  • Reduction of cardiac chamber dimensions

  • Improved exercise capacity

Factors that influence the responsiveness of patients to CRT or that are used to identify patients who will be responsive to CRT include the following:

  • QRS complex duration

  • Ventricular dyssynchrony (by echocardiography)

  • Successful lead placement

  • Physiologic atrioventricular delay

CRT requires left ventricular lateral wall pacing, which is achieved by placement of an epicardial lead via the coronary sinus. Multiple-guide catheter systems are available for coronary sinus cannulation, with most designs favoring a left pectoral approach. Coronary sinus phlebography facilitates placement by demonstrating vessel size, position, and angulation. Left anterior oblique and right anterior oblique projections are obtained with cine recording during injection of 10-15 mL of contrast in the coronary sinus.

A guide wire is inserted through the catheter positioned in the coronary sinus and maneuvered to the target venous branch. The coronary sinus lead is advanced over the guide wire into the desired branch of the coronary venous system.

The guide wire and guide catheter are withdrawn, leaving the coronary sinus lead in place. After acceptable thresholds and impedance are ensured, the lead is secured to the pectoralis with a nonabsorbable suture.

Identifying ideal sites for biventricular pacing has proven elusive when the criteria of latest epicardial activation, cumulative biventricular-paced QRS width, and empiric placement on the posterolateral wall are employed. Micromanometer recordings of the first derivative of left ventricular pressure (dP/dt) and 3-dimensional echocardiographic wall motion analysis provide superior information regarding lead site placement, but they are not widely used in clinical settings.

Frequently encountered difficulties include problems in cannulating the coronary sinus, acute angulation of the target venous vessels, and the absence of suitably sized veins in the left ventricular pacing region of interest. Right pectoral positioning of the biventricular pacing leads is more difficult in the presence of right subclavian–superior vena caval angulation and frequently requires the use of a deflectable guide catheter.



Medication Summary

The goals of pharmacotherapy are to reduce morbidity and prevent complications.

Antibiotics, Other

Class Summary

Routinely, cefazolin 1 g is administered intravenously (IV) 1 hour before the procedure. If the patient is allergic to penicillins or cephalosporins, vancomycin 1 g IV or another appropriate antibiotic may be administered preoperatively.


Cefazolin is a first-generation semisynthetic cephalosporin that arrests bacterial cell wall synthesis, inhibiting bacterial growth.


Vancomycin is a potent antibiotic that is directed against gram-positive organisms and that is active against Enterococcus species. It is useful in the treatment of septicemia and skin structure infections. Vancomycin is indicated for patients who cannot receive or have not responded to penicillins and cephalosporins and for patients who have infections with resistant staphylococci.

Local Anesthetics, Amides

Class Summary

Local anesthetics block the initiation and conduction of nerve impulses. Anesthetics used for the permanent pacemaker insertion include bupivacaine and lidocaine.

Bupivacaine (Marcaine)

Bupivacaine decreases permeability to sodium ions in neuronal membranes. This results in the inhibition of depolarization, blocking the transmission of nerve impulses.

Lidocaine (Xylocaine)

Lidocaine is an amide local anesthetic used in 1-2% concentration. The 1% preparation contains 10 mg of lidocaine for each 1 mL of solution; the 2% preparation contains 20 mg of lidocaine for each 1 mL of solution. Lidocaine inhibits depolarization of type C sensory neurons by blocking sodium channels.

To improve local anesthetic injection, cool the skin with ethyl chloride before injection. Use smaller-gauge needles (eg, 27 gauge or 30 gauge). Make sure the solution is at body temperature. Infiltrate very slowly to minimize the pain. The time from administration to onset of action is 2-5 minutes, and the effect lasts for 1.5-2 hours.