Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_3597_Библиотеки_им_академика_М_И_Перельмана
.pdf
272 5 —
https://t.me/med1917
American Association for Vascular Surgery/Society for Vascular Surgery, Society for
Cardiovascular Angiography and Interventions, Society for Vascular Medicine and
Biology, Society of Interventional Radiology, and the ACC/AHA Task Force on Practice Guidelines (Writing Committee to Develop Guidelines for the Management of
Patients with Peripheral A rterial Disease): endorsed by the American A ssociation of
Cardiovascular and Pulmonary Rehabilitation; National Heart, Lung, and Blood Institute; Society for Vascular Nursing; TransAtlantic Inter-Society Consensus; and Vascular Disease Foundation. Circulation 113:e463–e654, 20 06.
Jenkins JS, Patel SN, White CJ, et al: Endovascular stenting for vertebral arter y stenosis.
J Am Coll C ardiol 55:538–542, 2010.
Jongkind V, Akkersdijk GJ, Yeung KK, et al: A systematic review of endovascular treat-
ment of extensive aortoiliac occlusive disease. J Vasc Surg 52:1376–1383, 2010.
Klein AJ, Feldman DN, Aronow HD, et al: SCAI expert consensus statement for aorto-iliac
arter ial intervention appropriate use. Catheter Cardiovasc Inter v 84(4):520–528, 2014.
Klein AJ, Pinto DS, Gray BH, et al: SCAI expert consensus statement for femoral-popliteal
arter ial intervention appropriate use. Catheter Cardiovasc Interv 84(4):529 –538, 2014.
Laird JR, Katzen BT, Scheinert D, et al: RESILIENT Investigators. Nitinol stent implantation
versus balloon angioplasty for lesions in the superficial femoral arter y and proximal
popliteal artery: twelve -month results from the RESILIEN T randomized trial. Circ
Cardiovasc Interv 3:267–276, 2010.
Leesar MA, Varma J, Shapira A, et al: Prediction of hypertension improvement after stent-
ing of renal artery stenosis: comparative accuracy of translesional pressure gradients,
intravascular ultrasound, and angiography. J Am Coll Cardiol 53(25):2363–2371, 2009.
Morrow DA, Braunwald E, Bonaca MP, et al: Vorapaxar in the secondary prevention of
atherothrombotic events. N Engl J Med 366(15):1404–1413, 2012.
Murphy TP, Cutlip DE, Regensteiner JG, et al: Supervised exercise versus primary stenting
for claudication resulting from aortoiliac peripheral artery disea se: six-month outcomes from the claudication: exercise versus endoluminal revascularization
(CLEVER) study. Circulation 125:130–139, 2012.
Norgren L, Hiatt WR, Dormandy JA, et al: Inter-Society Consensus for the Management
of Peripheral A rterial Disease (TASC II). J Vasc Surg 45(suppl S):S5 –S67, 2007.
North American Symptomatic Carotid Endarterectomy Trial collaborators: Beneficial
effect of carot id endarterectomy in symptomatic patients with high-gr ade carotid
stenosis. N Engl J Med 325:445–453, 1991.
Patel SN, White CJ, Collins TJ, et al: Catheter-based treatment of the subclavian and
innominate arteries. Cath Cardiova sc Inter v 71:963–968, 20 08.
Rooke TW, Hirsch AT, Misra S, et al: 2011 ACCF/AHA focused update of the guideline for
the management of patients with peripher al arter y disease (updating the 2005 guideline): a report of the American College of Cardiology Foundation/American Heart
Association Task Force on Pract ice Guidelines: developed in collaboration with the
Society for Cardiovascular Angiography and Inter ventions, Societ y of Inter ventional
Radiology, Society for Vascular Medicine, and Society for Vascular Surger y. Cath
Cardiovasc Interv 79:501–531, 2011.
Sacco R L, Adams R, Albers G, et al: Guideline s for prevention of stroke in patients with
ischemic stroke or transient ischemic attack: a statement for healthcare professionals
from t he Amer ican Heart Ass ociation/American Stroke A ssociation Council on
Stroke: co -sponsored by the Council on Cardiovascular Radiology and Intervention:
the American Academy of Neurolog y affirm s the value of this guideline. Stroke
37:577–617, 2006.
Scheiner t D, Katsanos K, Zeller T, et al: A prospective randomized multicenter compari-
son of balloon angioplast y and infrapopliteal stenting with the sirolimus eluting stent
in patients with ischemic peripheral arterial disease. J Am Coll Cardiol 60:2290, 2012.
Scheiner t D, Scheinert S, Sax J, et al: Prevalence and clinical impact of stent fractures
after femoropopliteal stent ing. J Am Coll Cardiol 45:312–315, 2005.
Schillinger M, Sabeti S, Loewe C, et al: Balloon angioplasty versus implantation of nitinol
stents in the superficial femoral artery. N Engl J Med 354:1879–1888, 2006.
Selvin E, Erlinger TP: Prevalence of and risk factors for peripheral arterial disease in the
United States: results from the National Health and Nutrition Examination Survey,
1999-2000. Circulation 110:738–743, 2004.
Stewart KJ, Hiatt WR, Regensteiner JG, et al: Exercise training for claudication. N Engl J
Med 347:1941–1951, 20 02.
Tepe G, Zeller T, Albrecht T, et al: Local delivery of paclitaxel to inhibit restenosis during
angiopla sty of the leg. N Engl J Med 358:689 –699, 2008.
Tetteroo E, van der Graaf Y, Bosch JL, et al: Randomised compari son of primary stent
placement versus primary angiopla sty followed by selective stent placement in
patients with iliac-artery occlusive disease. Dutch Iliac Stent Trial Study Group.
Lancet 351:1153–1159, 1998.
Warfarin Antiplatelet Vascular Evaluation Trial Investigators, Anand S, Yusuf S, et al: Oral
anticoagulant and antiplatelet therapy and peripheral arterial disease. New Eng J
Med 357(3):217–227, 2007.
Willegendael EM, Teijink JA, Bartelink ML, et al: Smoking and the patency of lower
extremity by pass grafts: a meta-analysis. J Vasc Surg 42(1):67–74, 2005.
Yadav JS, Wholey MH, Kuntz RE, et al: Protected carotid-artery stenting versus endarter-
ectomy in high-risk patient s. N Engl J Med 351:1493–1501, 2004.
Ye W, Liu CW, Ricco JB, et al: Early and late outcomes of percutaneous treatment of
TransAtlantic Inter-Society Consen sus class C and D aorto -iliac lesions. J Vasc Surg
53:1728 –1737, 2011.
Peripheral Arterial Disease and Angiography
6
https://t.me/med1917
The Electrophysiology
Laboratory and
Electrophysiologic
Procedures
SCOTT W. FERREIRA • ALI A. MEHDIRAD
During the past two decades, the dedicated electrophysiology laboratory has evolved into a highly specialized procedure room wherein a variety of procedures are offered, ranging from diagnostic
elec trophysiologic (EP) studies, curative catheter ablation procedures, implantation of loop recorders, and pacemakers, defibrillators,
and resynchronization therapy devices to extraction of chronic indwelling leads.
The electrophysiologic study (EPS) is an invasive procedure that
involves the placement of multipolar catheter electrodes at various
intracardiac sites. Electrode catheters are routinely placed in the right
atrium (RA), across the tricuspid valve annulus in the area of the
atrioventricular (AV) node and His bundle (a special part of the conduction system), in the right ventricle (RV), in the coronary sinus, and
sometimes in the left ventricle (LV; Fig. 6 -1). The general purposes of
EPS are to characterize the EP properties of the conduction system,
induce and analyze the mechanism of arrhythmias, and evaluate the
effects of therapeutic interventions. Invasive EP techniques and procedures are routinely used in the clinical management of patients who
have supraventricular and ventricular arrhythmias (Box 6-1). In today’s
laboratory, the use of computer-generated “electroanatomical maps”
are very much a part of the jargon, and even a novice must be able to
recognize the color-coded activation patterns of common arrhythmias
shown later in this chapter. Individuals seeking a more in-depth discussion of the procedures and concepts described should refer to the
Suggested Readings section later in this chapter.
Equipment
An EP laboratory is equipped with radiographic imaging systems, a
recording and monitoring system, a stimulator, and all drugs and
equipment required for advanced cardiovascular life support (ACLS)
(Fig. 6-2). Although a dedicated laboratory would be preferable, in
many institutions, these procedures are performed in the cardiac
hemodynamic-angiographic catheterization laboratory. If used for
pacemaker and defibrillator implantation procedures, the room should
have air filtering equivalent to that in a surgical operating room.
Although expensive and elaborate equipment cannot substitute
for an experienced and careful operator, the use of inadequate equipment may prevent adequate amounts of data from being collected and
can make all the difference between success and failure. The arrhythmia targeted determines what equipment is required. A complete
273
274 6 —
https://t.me/med1917
Coronary sinus catheter
Figure 6 -1
Multipolar catheters are positioned in the high right atrium (RA) near the
sinus node, area of the atrioventricular (AV) node and His bundle, right
ventricular (RV) apex, and coronary sinus.
The Electrophysiology Laboratory and Electrophysiologic Procedures
RA catheter
Sinus node
AV node
RV catheter
Tricuspid valve
Purkinje system
Catheter positions for routine electrophysiologic study (EPS).
His bundle catheter
Bundle of His
Bundle branches
Box 6 -1 Clinical Applications of Electrophysiologic Studies
Diagnostic
• Diagnose SND
• Determine site of AV nodal block
• Define cause of syncope of unclear origin
• Differentiate VT from SVT in cases of wide- complex tachycardia
• Define mechanism of SVT or VT and map site of origin of tachyc ardia
Therapeutic
• Guide drug therapy for sust ained VT, aborted sudden death, or SVT
• Select appropriate candidates for cardioverter- defibrillator and
anti- tachycardia pacing therapy
• Test ef ficacy of device therapy for ventricular tachyarrhy thmias
• Select appropriate candidates for catheter ablative and sur gical therapy
• Test ef ficacy of ablative and surgical therapies
Interventional
• AV nodal ablation or modification for AF
• Ablation for atrial tachycardia and atrial flutter
• AV nodal modification (slow-pathway or fast-pathway ablation)
• Accessory pathway ablation in WP W syndrome
• Ablation of VT
Prognostic
• Risk stratification in asymptomatic WPW syndrome
• Risk stratification in patients after myocardial infarction
• Risk stratification in patients with nonsustained VT
AF, Atrial fibrillation; AV, atrioventricular; SVT, supraventricular tachycardia; SND,
sinus node dysfunction; VT, ventricular ta chycardia; WPW, Wolff-Parkinson -White.
evaluation of most arrhythmias that may require activation mapping
necessarily involves the use of multiple catheters, several recording
channels, a programmable stimulator, and sophisticated and computerized three-dimensional (3D) mapping systems. Thus, an appropriately equipped laboratory should provide all of the equipment
necessary for the most detailed study.
Electrode Catheters
Diagnostic Catheters
The hallmark feature of an EP catheter is the presence of at least two
ring electrodes that can be used for bipolar and unipolar pacing and
https://t.me/med1917
6 —
The Electrophysiology Laboratory and Electrophysiologic Procedures 275
Stimulator
EP recorder/
analyzer
system
Constant
current
source
Fluoroscopy
Printer
Physician
Signal processor
(amplifiers/filters)
Switch
box
Catheters
Patient
Nurse
Defibrillator
Crash
cart
Figure 6-2 General setup of the equipment used for electrophysiologic
studies (EPSs). EP, Electrophysiologic.
recording of local myocardial electrical activity. The material used to
construct these catheters may be of the woven Dacron variety or synthetic materials, such as plastic or polyurethane. The number of electrodes in these catheters can var y between 2 and 20, interelectrode
spacing between 2 and 20 mm, and thickness between 4 F and 7 F.
The shape of these catheters can vary on the basis of the structures
that they are designed to map: the crista terminalis, His bundle, coronary sinus, or pulmonary vein ostium. Typical EP catheters are shown
in Figure 6-3.
Ablation Catheters
Ablation catheters of various designs allow the operator to map and
deliver energy in a very precise manner. These catheters var y with
respect to the length of the ablation/tip electrode, which can range
from 3.5 to 10 mm in length. Figure 6-4 shows commonly used ablation
catheters. Notice that the tip of the catheter can be deflected to allow
for the arrhythmogenic myocardium to be reached. Conventionally,
the tip of the ablation catheter is longer than the electrode of a diagnostic catheter, to prevent overheating of the ablation electrode with
consequent coagulum formation. Prevention of overheating of the
ablation electrode can also be achieved by actively cooling with saline
irrigation.
Electroanatomical Mapping Catheters
In the mid 1990s, a novel technology termed nonfluoroscopic electroanatomical mapping revolutionized the practice of interventional EP.
Electroanatomical mapping systems integrate three functionalities,
namely, (1) nonfluoroscopic catheter localization in 3D space, (2) 3D
display of activation sequences and electrogram voltage, and (3) integration of this electroanatomical information with noninvasive images
of the heart—that is, computed tomography, magnetic resonance
images, or ultrasound images (image fusion). Two leading mapping
systems are available and most laboratories use one or both. They are
(1) the CARTO 3 system, manufactured by Biosense Webster, Inc., and
(2) the NavX system, manufactured by St. Jude Medical.
CARTO 3. In the mid 1990s, Biosense Webster, Inc. created a catheter
that has the appearance of a standard ablation catheter with a magnetic sensor within the shaft near the tip. Together with a reference
sensor, it can be used to precisely map the 3D spatial location of the
catheter (Fig. 6-5). The electroanatomical mapping system is called
the CARTO 3 system and consists of the reference and catheter sensor,
an external ultra-low magnetic emitter (Figs. 6 -6 and 6-7), and a processing unit. The amplitude, frequency, and phase of the sensed magnetic fields contain information to solve the algebraic equations,
yielding the precise locations (see Fig. 6-6) in three dimensions (x, y,
276 6 —
https://t.me/med1917
A
The Electrophysiology Laboratory and Electrophysiologic Procedures
B
Figure 6- 3 A, Several types of multipolar catheters used in routine elec-
trophysiologic studies (EPSs). Note the difference in the number of electrodes and in spacing between the electrodes among the various catheters.
B, Proximal end of a quadripolar electrode catheter. The number on each
pin corresponds to the electrode position at the tip of the catheter, with D
representing the most-distal electrode.
and z axes) and orientation of the catheter tip sensor (roll, pitch, and
yaw). An electrogram can also be recorded simultaneously in space,
and thus, an electroanatomical map can be generated. The catheter
can also be moved without fluoroscopy, thus decreasing radiation
exposure. An example of atrial tachycardia that arose from a focal
point that was mapped and ablated successfully with the use of the
CARTO 3 system is shown in Figure 6-7 for focal tachycardia. Shown
is a left anterior oblique (LAO) of an electroanatomical map of the
right and left atria as well as the coronary sinus. The activation data
https://t.me/med1917
6 —
The Electrophysiology Laboratory and Electrophysiologic Procedures 277
Figure 6-4 Specialized large -tip catheter electrodes designed for ablative
procedures.
D3
D1
D2
Figure 6-5 Image illustrates principles of operation of the CARTO 3 sys-
tem; specifically, how catheter location is determined. The location pad,
fixed beneath the patient table, is constructed of three coils that generate
ultra-low magnetic fields (1, 2, and 3 kHz). The emitted fields possess well known temporal and spatial distinguishing characteristics that “code” the
mapping space around the patient’s chest. Sensing of the magnetic field
by the location sensor (passive) enables determination of the location and
orientation of the catheter in 6 degrees of freedom.
seen with the color scale show the arrhythmia to arise from the ostium
of the coronary sinus.
NavX. The NavX system uses three low-amplitude high-frequency
current fields that are generated in three axes over the patient’s thorax
to compute the position of an electrode in the thorax relative to a reference electrode that can be placed in the heart or on the patient’s
thorax. On the basis of these measurements, the system then displays
the position of any EP catheter. The advantage of this system is that
multiple catheters can be displayed, and unlike the CARTO 3 system,
they are not limited to the products of a single manufacturer. Figure
6-8 shows an example of an LAO cranial view of an electroanatomical
map of the left atrium (LA, purple shell) along with the four pulmonary
veins and the left atrial appendage (LAA, green) constructed with
NavX. Also seen are the coronary sinus catheter, tip of the ablation
278 6 —
https://t.me/med1917
Figure 6-6 Ultra-low external magnetic field emitter used in the CARTO 3
system. This device is placed below the patient. The system comprises a
miniature passive magnetic field sensor located at the tip of the catheter,
external ultra-low magnetic field emitter, and processing unit. The system
uses the magnetic technology to accurately determine location and orientation of the catheter in 6 degrees of freedom (x, y, z, roll, pitch, and yaw)
and simultaneously records the intracardiac local electrogram from its tip.
The three -dimensional (3D) geometry of the chamber is reconstructed in
real time with the electrophysiologic (EP) information, which is color- coded
and superimposed on the electroanatomical map.
The Electrophysiology Laboratory and Electrophysiologic Procedures
catheter, and a circular mapping catheter. This map was performed in
a patient undergoing catheter ablation of atrial fibrillation (AF).
Junction Box and Recording Apparatus
The junction box and recording apparatus consists of pairs of numbered multiple pole switches matched to each recording and stimulation channel and permits the ready selection of any pair of electrodes
for stimulation or recording. Current computer junction boxes come
in banks of 8 or 16. Nowadays, the signal processor (filters and amplifier), visualization screen, and recording apparatus are incorporated
as a single unit in the form of a computerized system. GE Healthcare,
EP Med Systems (St. Jude Medical), and Bard Electrophysiology manufacture popular systems. Eight to 14 amplifiers should be available to
process surface electrocardiogram (ECG) leads simultaneously with
multiple intracardiac electrograms. The number of amplifiers can be
as many as 128 in some systems. Intracardiac recordings must be
displayed simultaneously, with at least three surface ECG leads. Most
computers allow several pages to be stored, with one page displaying
a 12-lead ECG. Thus, an operator can always have a 12-lead ECG
recorded simultaneously while observing intracardiac electrogram
data. The amplifiers used for recording intracardiac electrograms must
have the ability to have gain modification and alter both high and low
band pass filters to permit appropriate attenuation of the incoming
signals. For example, the His bundle electrogram is most clearly visualized when the signal is filtered between 30 and 40 Hz (high pass) and
400 and 500 Hz (low pass; Fig. 6-9). In addition, assessing unipolar
electrograms also requires acquiring open filters (0.05 to 500 Hz).
https://t.me/med1917
6 —
The Electrophysiology Laboratory and Electrophysiologic Procedures 279
LA
RA
CS
Figure 6-7 Focal tachycardia image. Figure shows an electroanatomical
map of right and left atria (RA; LA) along with the coronary sinus (CS). The
activation sequence pattern of an atrial tachycardia is shown. Red, Sites of
early activation; blue and purple, late sites. The activation pattern shows a
focal arrhythmia arising from the anterior lip of the coronary sinus ostium.
Maroon dots, Sites where catheter ablation was performed. LAO, Left ante rior oblique; LAT, lateral.
Stimulation Apparatus
Most EPSs require a complex programmable stimulator that has (1) a
constant current source, (2) minimal current leakage, (3) the ability
to pace at a wide range of cycle lengths (100 to 2000 msec) from at
least two simultaneous sites, (4) the ability to introduce multiple extrastimuli, and (5) the ability to synchronize the stimulator to appropriate
electrograms during spontaneous and paced rhythms. The stimulator
is equipped with dials or switches by which the pacing intervals and
coupling intervals of the extrastimuli may be adjusted (Fig. 6 -10). A
junction box that interfaces with the recording system and stimulator
facilitates changes in the pacing site without the need to disconnect
catheters. The stimulator should be able to deliver variable currents
that can be accurately controlled, with a range from 0.1 to 10 mA. The
ability to change pulse widths is also useful. The results of programmed
stimulation can be influenced by the delivered current, and for consistency and safety, stimulation is generally performed at two and a
half times diastolic threshold.
280 6 —
https://t.me/med1917
Figure 6- 8 Example of lef t anterior oblique (LAO) cranial view of an elec-
troanatomical map of the lef t atrium (LA, purple shell) along with the four
pulmonary veins and left atrial appendage (LAA, green) constructed with
NavX is shown in this figure. Also seen are the coronary sinus catheter and
the tip of the ablation catheter and a circular mapping catheter. This map
was per formed in a patient undergoing catheter ablation of atrial fibrillation
(AF). CS, Coronary sinus; LIPV, left interior pulmonary vein; LSPV, left superior
pulmonary vein; RSPV, right superior pulmonary vein. (EnSite, Velocity,
Quartet, SJM Confirm and St. Jude Medical are trademarks of St. Jude
Medical, Inc. or its related companies. Reprinted with permission of St. Jude
Medical, © 2015. All rights reserved.)
The Electrophysiology Laboratory and Electrophysiologic Procedures
Ablation
catheter
RSPV
LA
LSPV
LAA
LIPV
Circular mapping
CS catheter
catheter
A B
C D
Figure 6-9 Effect of filtering frequency on the His bundle electrogram.
Pacing from the proximal coronar y sinus is performed at a basic cycle length
of 60 msec. In each of the four panels, surface leads I, II, aVF, and V1 are
shown. A recording catheter is placed in the standard position to record the
His bundle electrogram; and recordings from the proximal, mid, and distal
electrode pairs are displayed. A, His bundle electrograms, where the signal
is filtered bet ween 30 Hz (high pass) and 500 Hz (low pass); B, recording
made between filter settings of 0.05 and 500 Hz; C, recording made
between 30 and 1000 Hz; D, recording made between 100 and 500 Hz.
The clearest recording of the His bundle electrogram occurs with a filtering
of the signals below 30 Hz and above 500 Hz (A).
It is preferable that the stimulator, computerized data recorder,
and other devices used in EP are permanently installed. Most laboratories use a stimulator and computer system that modifies all input
signals and stores them in an optical disc. All equipment must be
grounded, and other aspects of electrical safety must be ensured
because even small amounts of leakage current can pass to the patient
and potentially induce arrhythmias. A technical engineer must check
https://t.me/med1917
6 —
The Electrophysiology Laboratory and Electrophysiologic Procedures 281
Figure 6-10 Junction box/recording apparatus and stimulation apparatus.
Image shows the Prucka CardioLab EP system. Also seen within the white
oval is a computerized stimulator manufactured by Micropace. The junction
box inter faces with the recording system and stimulator, thus allowing us
to change the pacing site without the need to disconnect catheters.
the equipment so that leakage current remains <10 mA. Figure 6-2
shows an illustration of the organization of the relevant equipment
required during an EPS.
Defibrillator
A functioning defibrillator should be available at the patient’s side
throughout all EPSs. A backup defibrillator is optimal in case of a rare
but potentially disastrous failure of one defibrillator. Defibrillators
should be tested before each study and equipped with an emergency
power source. Many laboratories use commercially available R2 pads,
which are placed on the patient before the EPS procedure begins. One
pad is placed under the right scapula and the other on the anterior
chest over the left ventricular (LV) apex and connected to the defibrillator with an adapter. In rare instances in which transthoracic
defibrillation fails to convert induced ventricular fibrillation (VF),
emergency defibrillation through an intracardiac electrode catheter
may be effective in terminating the arrhythmia (Fig. 6-11). It is our
practice to have biphasic defibrillators in our laboratories.
Because the physician’s attention is often focused on the stimulator and electrograms, he or she relies heavily on the nurse to monitor
the patient’s condition and communicate significant changes. The
nurse usually sits between the patient and the cardioverter-defibrillator
and crash cart. The nurse monitors the patient’s blood pressure, heart
rate (HR), rhythm, and oxygen saturation via a pulse oximeter; administers drugs for diagnostic and therapeutic interventions during EPS;
and performs cardioversion or defibrillation when an induced hemodynamically unstable arrhythmia appears. Optimally, a second nurse
is available during procedures to administer medications or assist in
technical aspects of the procedure.
Implantation of Pacemakers, Defibrillators,
and Resynchronization Therapy Devices
Pacemakers
Pacemakers, the original devices implanted for cardiac rhythm management, have the ability to provide electrical stimulation (pace) to
Соседние файлы в папке Библиотека им академика М.И. Перельмана