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•Instruct the patient not to manipulate the pacemaker wires or pulse generator.
•Give the patient with a permanent pacemaker the manufacturer’s identification card, and tell him to carry it at all times.
•Emphasize the importance of identifying pacemaker problems or battery depletion if your patient receives pacemaker checks over the telephone.
•Teach the patient and his family how to care for the incision, how to take a pulse, and what to do if the pulse drops below the pacemaker rate.
•Advise the patient to avoid tight clothing or other direct pressure over the pulse generator, to avoid magnetic resonance imaging scans and certain other diagnostic studies, and to notify the practitioner if he feels confused, light-headed, or short of breath. The patient should also notify the practitioner if he has palpitations, hiccups, or a rapid or unusually slow heart rate.
Teach your patient the ABCs of life with a pacemaker.
A look at biventricular pacemakers
Biventricular pacing is used in the treatment of some patients with class III and IV heart failure, with both systolic heart failure and intraventricular conduction delay. Also called cardiac resynchronization therapy, biventricular pacing reduces symptoms and improves the quality of life in patients with advanced heart failure.
Two ventricles, three leads
Unlike other pacemakers, a biventricular pacemaker has three leads rather than two: one to pace the right atrium, one to pace the right ventricle, and one to pace the left ventricle. Both ventricles are paced at the same time, causing them to contract simultaneously, increasing cardiac output.
An important tip
Unlike traditional lead placement, the electrode tip for the left ventricle is placed in the coronary sinus to a branch of the cardiac vein. Because this electrode tip isn’t anchored in place, lead displacement may occur. (See Biventricular lead placement, page 192.)
Improves symptoms and quality of life
Biventricular pacing produces an improvement in the patient’s symptoms and activity tolerance. Moreover, biventricular pacing improves left ventricular remodeling and diastolic function and reduces sympathetic stimulation. As a result, in many patients,
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Biventricular lead placement
The biventricular pacemaker uses three leads: one to pace the right atrium, one to pace the right ventricle, and one to pace the left ventricle. The left ventricular lead is placed in the coronary sinus. Both ventricles are paced at the same time, causing them to contract simultaneously, improving cardiac output.
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Subclavian vein |
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Generator |
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Right atrial lead |
Right atrium |
Left ventricular lead |
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(in coronary sinus vein) |
Right ventricle |
Left ventricle |
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Right ventricular lead |
the progression of heart failure is slowed and quality of life is improved.
Biventricular pacing produces an improvement in quality of life.
Different ventricles, different timing
Under normal conditions, the right and left ventricles contract simultaneously to pump blood to the lungs and body, respectively. However, in heart failure, the damaged ventricles can’t pump as forcefully and the amount
of blood ejected with each contraction is reduced. If the ventricular conduction pathways are also damaged, electrical impulses reach the ventricles at different times, producing asynchronous contractions. This condition, called intraventricular conduction defect, further reduces the amount of blood that the heart pumps, worsening the patient’s symptoms.
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Sympathetic response
To compensate for reduced cardiac output, the sympathetic nervous system releases neurohormones, such as aldosterone, norepinephrine, and vasopressin, to boost the amount of blood ejected with each contraction. The resultant tachycardia and vasoconstriction increase the heart’s demand for oxygen, reduce diastolic filling time, promote sodium and water retention, and increase the pressure that the heart must pump against. The effect on the patient is a worsening of symptoms.
Who’s a candidate?
Not all patients with heart failure benefit from biventricular pacing. Candidates should have both systolic heart failure and intraventricular conduction delay along with these characteristics:
•symptomatic heart failure despite maximal medical therapy
•moderate to severe heart failure (New York Heart Association class III or IV)
•QRS complex greater than 0.13 second
•left ventricular ejection fraction of 35% or less.
Ask the patient if he has a shellfish allergy before
pacemaker insertion.
Caring for the patient
Provide the same basic care for the patient with a biventricular pacemaker that you would for a patient with a standard permanent pacemaker. Specific care includes these guidelines:
•Before the procedure, ask the patient if he has an allergy to iodine or shellfish because contrast medium is used to visualize the coronary sinus and veins. Notify the practitioner if an allergy exists.
•Because of the position of the left ventricular lead, watch for stimulation of the diaphragm and left chest wall. Notify the practitioner if this occurs because the left ventricular lead may need repositioning or the pacing output may need to be reprogrammed.
•Observe the ECG for pacemaker spikes. Although both ventricles are paced, usually only one pacemaker spike is seen.
•Note the presence of positive R waves in leads V1, I, and aVL. Notify the practitioner if this isn't the case or if the R wave direc-
tion changes at any time.
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What to teach the patient
Provide the same basic teaching that you would for the patient receiving a permanent pacemaker. Additionally, when a patient gets a biventricular pacemaker, be sure to cover these points:
•Explain to the patient and his family why a biventricular pacemaker is needed, how it works, and what they can expect.
•Tell the patient and his family that it’s sometimes difficult to place the left ventricular lead and that the procedure can take 3 hours or more.
•Stress the importance of calling the practitioner immediately if the patient develops chest pain, shortness of breath, swelling of the hands or feet, or a weight gain of 3 lb (1.4 kg) in 24 hours or 5 lb (2.3 kg) in 72 hours.
A look at radiofrequency ablation
Radiofrequency ablation is an invasive procedure that may be used to treat arrhythmias in patients who haven’t responded to antiarrhythmic drugs or cardioversion or can’t tolerate antiarrhythmic drugs. In this procedure, bursts of radiofrequency energy are delivered through a catheter to the heart tissue to destroy the focus of the arrhythmia or block the conduction pathway.
Who’s a candidate?
Radiofrequency ablation is effective in treating patients with atrial tachycardia, atrial fibrillation and flutter, ventricular tachycardia, AV nodal reentry tachycardia, and Wolff-Parkinson-White (WPW) syndrome.
Understanding the procedure
The patient first undergoes an electrophysiology study to identify and map the specific areas of the heart that’s causing the arrhythmia. The ablation catheters are inserted into a vein, usually the femoral vein, and advanced to the heart where short bursts of radiofrequency waves destroy small targeted areas of heart tissue. The destroyed tissue can no longer conduct electrical impulses. Other types of energy may also be used, such as microwave, sonar, or cryo (freezing).
With radiofrequency ablation, a burst of energy is sent right to the part of me that’s causing the arrhythmia.
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Hitting the target
In most patients with atrial fibrillation, the tissue inside the pulmonary vein is responsible for the arrhythmia. Targeted radiofrequency ablation is used to block these abnormal impulses. (See
Destroying the source.)
Destroying the source
In radiofrequency ablation, special catheters are inserted in a vein and advanced to the heart. After the source of the arrhythmia is identified, radiofrequency energy is used to destroy the source of the abnormal electrical impulses or abnormal conduction pathway.
AV node ablation
If a rapid arrhythmia originates above the atrioventricular (AV) node, the AV node may be destroyed to block impulses from reaching the ventricles.
Pulmonary vein isolation and ablation
If ectopic foci in the pulmonary vein are the source of the atrial fibrillation, radiofrequency energy is used to destroy the tissue at the base of the pulmonary vein.
Pulmonary vein
SA node |
SA node |
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Radiofrequency |
Radiofrequency |
catheter |
catheter |
Right atrium |
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AV node |
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Radiofrequency energy is used to destroy the AV node.
Radiofrequency energy is used to destroy the tissue
where the atrium connects to the pulmonary vein.
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If a rapid arrhythmia that originates above the AV node (such as atrial fibrillation) isn’t terminated by targeted ablation, AV nodal ablation may be used to block electrical impulses from being conducted to the ventricles. After ablation of the AV node, the patient may need a pacemaker because impulses can no longer be conducted from the atria to the ventricles. If the atria continue to beat irregularly, anticoagulation therapy will also be needed to reduce the risk of stroke.
If the patient has WPW syndrome, electrophysiology studies can locate the accessory pathway and ablation can destroy it. When reentry is the cause of the arrhythmia, such as AV nodal reentry tachycardia, ablation can destroy the pathway without affecting the AV node.
How you intervene
When caring for a patient after radiofrequency ablation, follow these guidelines:
•Provide continuous cardiac monitoring, assessing for arrhythmias and ischemic changes.
•Place the patient on bed rest for 8 hours, or as ordered, and keep the affected extremity straight. Maintain the head of the bed between 15 and 30 degrees.
•Assess the patient’s vital signs every 15 minutes for the first hour, then every 30 minutes for 4 hours, unless the patient’s condition warrants more frequent checking.
•Assess peripheral pulses distal to the catheter insertion site as well as the color, sensation, temperature, and capillary refill of the affected extremity.
•Check the catheter insertion site for bleeding and hematoma formation.
•Monitor the patient for complications, such as hemorrhage, stroke, perforation of the heart, cardiac tamponade, arrhythmias, phrenic nerve damage, pericarditis, pulmonic vein stenosis or thrombosis, and sudden death.
What to teach the patient
When a patient undergoes radiofrequency ablation, be sure to cover these points:
•Discuss with the patient and his family why radiofrequency ablation is needed, how it works, and what they can expect.
•Warn the patient and his family that the procedure can be lengthy, up to 6 hours if electrophysiology studies are being done first.
Caring for the patient after
radiofrequency ablation requires specific guidelines as discussed here.