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Introduction toCoronary Angioplasty
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IosifXenogiannis
39
Case Presentation
Forty-six-year-old male visited the emergency department of
our hospital complaining for substernal chest pain and concomitant resting dyspnea that started approximately 3 h
prior. The patient was a heavy smoker, obese, and had no
other signicant medical history.
Blood pressure was 100/60 mmHg, heart rate was
110 bpm, respiratory rate was 22 breaths per minute and
SatO2 was 92%. The initial electrocardiogram showed
ST-segment elevation in leads ΙΙ, ΙΙΙ and a VF and ST-segment
depression in leads V4–V6. Echocardiography demonstrated
inferior, posterior, and lateral wall akinesia, with a moderately reduced left ventricular ejection fraction (35–40%) and
moderate mitral regurgitation. High-sensitive troponin-T
was 189pg/mL (normal values <15pg/mL).
The patient was led to the catheterization laboratory….
Background
It has been 45years since Dr. Andreas R.Grüntzig, in 1977,
performed the rst percutaneous coronary balloon angioplasty
recanalizing the left anterior descending coronary artery
(LAD) of a 38-year-old man suffering from angina pectoris.
The intervention was successful paving the way for the genesis of percutaneous coronary interventions (PCI). Since then,
important technological breakthroughs have been achieved
with the development of new catheters and balloons, specialized guidewires as well as the introduction of stents and
adjunctive devices, making PCI more effective and safe,
improving its short- and long-term outcomes. While only a
minority of patients, estimated at 10%, were eligible for PCI in
the early years of interventional cardiology, nowadays, even
the most complex subsets of coronary lesions are tried in
patients who would have otherwise been exclusively surgical
I. Xenogiannis (*)
Second Department of Cardiology, Attikon University Hospital,
National and Kapodistrian University of Athens Medical School,
Athens, Greece
candidates (i.e. left main disease, calcied lesions, three-vessel disease) [1]. In addition, advances in hemodynamic support devices, such as impella development, allowed the
performance of PCI in sicker patients with hemodynamic
instability or compromised ventricular function.
Continued at page 438
Indications
The goal of PCI is to alleviate patient’s symptoms and reduce
major adverse cardiovascular events (MACEs), including
death. Patients undergo PCI for either stable coronary artery
disease (CAD) or acute coronary syndromes (ACS)
(ST-segment elevation myocardial infarction [STEMI] and
non-ST-segment elevation myocardial infarction [nonSTEMI]/unstable angina). Whereas the advantage of PCI
compared to non-invasive management, in terms of survival
benet, has been established by multiple studies in the setting of ACS, this is not the case for stable CAD [2–4]. With
the exception of left main disease, no compelling data exist
showing a survival benet of PCI over optimal medical therapy for patients with stable CAD. [5] The contemporary
ISCHEMIA trial reported no reduction in MACE or death
rate in patients with moderate or severe ischemia randomized to receive an initial invasive strategy (74% PCI, 26%
coronary artery bypass graft surgery [CABG]) as compared
with those randomized to an initial conservative strategy.
Patients with left main disease and left ventricular ejection
infraction <35% were excluded [6]. Spontaneous MIs were
reduced in the invasive group at the expense of more periprocedural MIs [7]. On the other hand, invasive strategy resulted
in greater reduction in angina symptoms compared to noninvasive strategy [8]. Finally, a recent metanalysis which
included 25 randomized trials spanning from 1978 to 2020
reported that revascularization in patients with stable CAD
reduced cardiac mortality and spontaneous MI, illustrating
that even in stable CAD, revascularization may have an
effect on hard end-points apart from symptoms control [9].
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2024
G. Geroulakos et al. (eds.), Mastering Endovascular Techniques, https://doi.org/10.1007/978-3-031-42735-0_39
419
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I. Xenogiannis
Contraindications
It should be noted that in some cases, PCI may be a lifesaving intervention and at the same time the only therapeutic
option. Thus, in such clinical scenarios there are no absolute
contraindications.
Absolute contraindications:
– Bleeding disorders/diathesis (thrombocytopenia, coagu-
lopathy, active peptic ulcer)
– Inability of the patient to co-operate during the procedure
and take antithrombotic therapy
Relative contraindication:
– Inability to tolerate antiplatelets for the indicated period
of time
– Multiple PCI restenosis
– Unsuitable coronary anatomy such as saphenous vein
graft chronic total occlusion (CTO) [10]
Timing ofIntervention
Optimal time of intervention differs for each clinical scenario. “Time is myocardium” in ACS and especially in the
clinical setting of STEMI. Maximum accepted delay from
STEMI diagnosis to primary PCI (wire crossing the lesion)
is 120min in order to choose primary PCI over brinolysis,
otherwise brinolysis should be considered [11]. For patients
who present at primary PCI centers, time from STEMI diagnosis to primary PCI should be ideally ≤60min [11]. CABG
is reserved for STEMI patients who had an unsuccessful primary PCI and have a large jeopardized myocardial area.
Regarding non-STEMI/unstable angina, in very high-risk
patients (cardiogenic shock, hemodynamic or electrical
instability, heart failure, mechanical complications, refractory chest pain despite medical therapy, ST-segment depression in ≥6 leads with accompanying ST-segment elevation in
leads V1 and/or aVR) an immediate (< 2h) invasive strategy
should take place. For high-risk patients (established nonSTEMI, dynamic/new ST-segment or T-wave changes, transient ST-segment elevation, GRACE risk score > 140) an
early invasive strategy, within 24h, is recommended. For all
the other non-STEMI/unstable angina patients, non-invasive
stress test or coronary computed tomography angiography
(CCTA) is usually performed and then, according to the
results, coronary angiography follows or not.
For patients with stable CAD, coronary angiography/PCI
is performed as a scheduled intervention on the basis of a
positive non-invasive examination (stress test of CCTA) or
other high risk clinical or imaging features such as signicant
angina refractory to medical therapy or left ventricular dysfunction likely due to underlying stable CAD [12]. PCI can
be performed either immediately after diagnostic coronary
angiography, as an ad-hoc procedure, or at a later time. The
second option is usually selected for more complex subsets,
i.e., CTOs, severely calcied lesions or left main disease.
Pre-procedural Evaluation/Planning
Meticulous planning before the initiation of the operation is
key to success. The rst step is to evaluate the indication of
procedure (stable angina vs. ACS). After explaining, in detail,
the risks and benets of the procedure, as well as describing
the process, an inform consent should be obtained by the
patient. Oral consent is also acceptable in critical situations
such as STEMI or when the patient is in cardiogenic shock.
Thorough patient’s medical history, if time allows in case
of ACS, should be recorded. In specic, patient should be
asked for prior history of CAD, heart failure, valvular heart
disease, peripheral artery disease, bleeding disorders and
renal failure. Bleeding disorders should be corrected, if feasible, while patients with renal failure may have to be
hydrated before and after the procedure (for National Kidney
Foundation stages 3b and 4) or undergo prophylactic hemoltration (for National Kidney Foundation stage 4) especially before complex PCI. [13] Back pain or other conditions
should be sought out since it may cause patient discomfort
while on table, resulting in poor cooperation. Furthermore,
review of prior heart catheterizations, CCTA or CABG
reports, and ideally images and videos, is paramount.
Knowledge of prior access site and the type of catheters that
were used may save time as well as prevent unnecessary
waste of equipment.
History of allergies to contrast, latex or aspirin has to be
managed with pre-treatment with cortisone and antihistamines, usage of alternative types of gloves and potentially
patient desensitization respectively. It is important to clarify
if the patient is able to receive and maintain dual antiplatelet
therapy (DAPT). Bleeding disorders/high bleeding risk and
high chances of noncompliance with medication may preclude stent implantation since early DAPT discontinuation
increases signicantly the risk of in stent thrombosis.
Physical examination should focus on cardiovascular and
respiratory system. Low blood pressure may imply the presence of cardiogenic shock and the patient should be treated
with vasopressors and/or hemodynamic support devices.
Upper and lower extremity pulses have to be checked.
Absence of pulses can be the result of artery obstruction precluding its use for obtaining access. Surgical scar over the
anatomical site of a radial artery implies that the artery has
been harvested and thus is not available for gaining access.
Arteriovenous stulas for dialysis also exclude the corre-
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421
sponding arm as access site. In patients with apparent groin
ulcers, scars or morbid obesity, radial artery should, in general, be preferred. In case of heart murmurs, valvular heart
disease has to be sought out since it can affect the decision to
proceed with PCI or not. Peripheral edema, jugular vein distention, and the presence of rales during lung auscultation
are signs of congestive heart failure underlying the need for
diuretic administration before or during the operation since
the patient should ideally be euvolemic.
Hematocrit, platelet count, INR, creatinine and electrolytes such as potassium are the basic labs that should be
checked. Signicant anemia, thrombocytopenia, bleeding,
and electrolyte disorders have to be corrected, if possible,
before the operation. Serum beta hCG for women of childbearing potential could be checked.
Review of patient medication is crucial. Warfarin should
be discontinued 5 days before a scheduled coronary
angiography/PCI while for direct oral anticoagulants
(DOACs) 2days are enough in the absence of renal failure.
When creatinine clearance is between 15 and 49 mL/min
DOAC is in general hold for one or two additional days.
Radial access is preferred if the patient did not have the
chance to interrupt anticoagulants or for those with high
INR. Furthermore, antiplatelet administration has to be
checked and the patient should be loaded if he or she was not
previously on aspirin or P2Y12 inhibitor accordingly. Low
molecular weight heparin (LMWH) and unfractionated heparin crossover is discouraged so if the patient was already on
LMWH its use should be continued (see periprocedural antithrombotic agents administration) [14]. Metformin discontinuation before PCI is not routinely recommended but close
creatinine monitoring is mandatory. For patients with renal
failure, metformin should be withhold before the operation
and not be restated for at least 48h after [13]. Finally, administration of nitroglycerin is contraindicated in patients who
have recently used phosphodiesterase type 5 (PDE-5) inhibitors, namely sildenal, vardenal, and tadalal (within the
rst 24h from the administration of the rst two and 48h for
the third).
Monitoring
Close patient monitoring is imperative throughout intervention (Fig.39.1). Before the initiation of the intervention, specic monitoring responsibilities should be shared among the
Fig. 39.1 Patient monitoring during percutaneous coronary intervention (PCI). Patient’s rhythm and rate is recorded continuously (leads I
and II, at the top of the screen). Arterial blood pressure values and tracing morphology are appreciated. In this case, there are two arterial
blood pressure tracings because both coronary arteries were engaged,
as it happens in the vast majority of chronic total occlusion PCIs. The
red tracing is derived from the catheter in the left coronary artery while
the blue tracing is derived from the catheter in the right coronary artery.
Although, it is not routinely performed in every PCI, right heart catheterization is used for the estimation of pulmonary artery and capillary
wedge pressure in patients who are at high risk for hemodynamic compensation. In this case, a swan-ganz catheter records pulmonary artery
pressure (green tracing at the bottom)
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I. Xenogiannis
members of the interventional team (physicians, registered
nurses and technicians). Most of the times, a registered nurse
is responsible for continuously evaluating patient’s comfort
during the operation while a registered nurse or a technician
continuously monitors electrocardiogram and pressure waveform tracing. Patient discomfort may lead to movements that
predispose to complications. Administration of sedatives (i.e.,
1mg of midazolam i.v.) can help anxious patient to relax and
co-operate better. Analgesics such as opioids should be
offered to patients with arm (mostly due to spasm), back or
chest pain. Oxygen saturation has to be monitored continuously and dyspnea or tachypnea should be noted and managed usually with oxygen and/or diuretics administration.
Patient’s skin should also be examined in the setting of acute
onset of dyspnea since the presence of rush is likely to be
associated with allergy development to contrast or drugs. A
relaxed patient allows the operator to focus on the operation
without distractions and thus be more efcient.
Electrocardiogram (ECG) is constantly recorded during
the operation. Ideally, (at least) three leads that “look at” the
anterior, inferior and lateral left ventricle wall should be
used. ECG is checked for heart rhythm and rate.
Supraventricular or ventricular tachycardias may require
antiarrhythmic drug administration while when the patient
becomes hemodynamically unstable or develops ventricular
brillation, electric cardioversion is indicated. On the other
hand, bradyarrhythmias in the catheterization laboratory are
managed with atropine or temporary pacing. ST-segment
elevation or depression are associated with the presence of
ischemia and should be treated according to the cause that
provoked it.
Blood pressure tracing is another key element of optimal
patient monitoring in the catheterization laboratory.
Hypotension may be provoked by several causes that should
be sought out in a timely manner and treated accordingly:
• Cardiogenic shock due to large infarcts or mechanical
complications. Tachyarrhythmias also predispose to
hypotension.
• Inferior infarcts frequently lead to hypotension especially
when the right ventricle is involved and nitroglycerin has
been administered.
• Excess nitroglycerin administration or nitroglycerin
administration in patients with marginal blood pressure.
Co-administration of nitroglycerin in patients on PDE-5
inhibitors may result in severe hypotension.
• Hypovolemic shock due to excess blood loss. Usually this
can happen in the setting of retroperitoneal bleeding when
femoral artery has been used for access.
• Allergic shock as a reaction to drugs or contrast.
• Vasovagal reaction because of discomfort or excessive
pain.
• Tamponade.
• Pseudohypotension or false hypotension caused by the
presence of air or thrombus in the catheter or in the connection between catheter and pressure transducer.
Likewise, when the hemostatic valve or the Y-connector is
open, blood pressure will erroneously appear to be low.
Catheter kinking is another cause of false hypotension.
Bulky equipment within the catheter may also result in
recording low blood pressure on the arterial pressure tracing [15].
Extremely high blood pressure should also be treated as it
can potentially predispose to pulmonary edema.
It is important to investigate the morphology of the arte-
rial wave for pressure dampening or ventricularization (the
arterial waveform simulates with the waveform that is
recorded from the ventricles). Dampening is caused by toodeep engagement of the catheter or advancement of the catheter against aortic or coronary wall or next to an ostial
coronary lesion. Injections should be avoided as they may
lead to coronary artery dissection and the catheter should be
repositioned until a normal arterial waveform is recorded
(Fig.39.2).
The presence of “pulsus paradoxus” on the arterial tracing
is associated with tamponade development.
Contrast should be administered with caution. Risk scores
have been developed for the prediction of contrast-induced
acute kidney injury [16]. A simple rule is not to exceed
3.7×creatinine clearance (glomerular ltration rate) mL in
contrast [17]. If air kerma radiation dose exceeds 5–7 Gray
and the intervention is not about to end the operator has to
think about stopping the procedure [15].
Guid
g
39 Introduction toCoronary Angioplasty
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Fig. 39.2 Pressure
dampening upon engagement
of an aorto-ostial right
coronary artery lesion.
Reprinted from the Manual of
Percutaneous Coronary
Interventions. Emannouil
Brilakis. A step-by-step
approach. 2020. With
permission by Elsevier/
Academic press
Guide engaged
423
Pressure
dampening
e disengaged
Periprocedural Antithrombotic Agents
Administration
Before angioplasty/stent implantation the patient should be
on DAPT. If not already on DAPT, the patient has to be
loaded with aspirin 150–300 mg and a P2Y12 inhibitor. In
general, for stable CAD, clopidogrel 600 mg is preferred
while for ACS a more potent P2Y12 inhibitor is indicated such
as prasugrel 60mg or ticagrelor 180mg loading dose.
There are two categories of intravenous antiplatelet drugs
currently in use: glycoprotein IIb/IIIa inhibitors and the shortacting P2Y12 inhibitor, cangrelor. Two glycoprotein IIb/IIIa
inhibitors agents are available: eptibatide (double bolus of
180μg/kg i.v., given at a 10-min interval, followed by an infusion of 2.0μg/kg/min for up to18 h) and tiroban (bolus of
25μg/kg i.v. over 3min, followed by an infusion of 0.15μg/
kg/min for up to 18h). Glycoprotein IIb/IIIa inhibitors are not
routinely administered during PCI but only as a bail-out therapy in the presence of bulky thrombus. Cangrelor has a very
fast onset of action (2min) that lasts for 30–60min. It may be
considered in P2Y12 receptor inhibitor-naïve patients undergoing PCI and is very useful for patients who cannot be loaded
per os (i.e. intubated patients). The recommended bolus dose
is 30mg/kg i.v. followed by 4mg/kg/min infusion for at least
2h or the duration of the procedure (whichever is longer).
No dampenin
Unfractionated heparin is the most commonly used anticoagulant during PCI. The recommended dose is
70–100 units/kg, reduced to 50–70 units/kg when
concomitant glycoprotein IIb/IIIa inhibitor administration
takes place. Activated clotting time (ACT) should be
checked every 30–60min. The target ACT values are 250–
300s for most PCIs while higher ACT values are recommended for CTO PCI (300–350s for antegrade approach
and >300–350 sec for retrograde approach) and lower in
case of glycoprotein IIb/IIIa inhibitor administration (200–
250s). Bivalirudin is an alternate to unfractionated heparin
and is preferred in patients with history of heparin induced
thrombocytopenia (HIT). The recommended dose is:
0.75mg/kg IV, followed by infusion of 1.75mg/kg/h i.v. for
up to 4h after the procedure. The dose has to be modied
for patients with renal insufciency. Enoxaparin 0.5mg/kg
i.v. bolus, is another option. If the patient was already on s.c.
enoxaparin and the last dose was given less than 8h before,
then, no extra dose of enoxaparin or unfractionated heparin
is recommended. If the last dose was administered more
than 8h ago an additional 0.3mg/kg i.v. bolus dose is recommended. Crossover between unfractionated heparin and
LMWH is discouraged. If the patient was on fondaparinux,
a single dose of unfractionated heparin 85 units/kg is
recommended.
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Access
Radial and femoral artery are the most common sites of
access. Ulnar artery is relatively frequently used as an
alternate to radial artery whereas other sites such as branchial, axilliary or carotid artery or transcaval approach are
rarely used and are more of historical interest. Both the
American and European guidelines support the routine use
of radial artery for gaining access irrespectively from the
clinical setting (stable CAD and ACS) [13, 18]. In ACS the
use of radial artery has been associated not only with less
bleeding and vascular complications but, more importantly, with survival benet [19, 20]. Nevertheless, femoral
artery as the site of access could be preferred in specic
clinical contexts: complex PCI cases where large bore
catheters are used and increased support is essential, such
as CTO PCI.
Patients with prior CABG comprises a group of patients
that femoral access is usually required especially when both
internal mammary arteries have been used as grafts [21]. In
addition, femoral artery is the access site of choice in transcatheter aortic valve implantation or in other structural procedures and in cases where hemodynamic support devices
should be placed.
Although echocardiographic guidance for femoral artery
puncture has been associated with higher rates of rst-pass
success, lower number of attempts, less venipuncture and
lower number of access complications, still, many operators
use only femoral pulsation and anatomic landmarks, with or
without uoroscopy, to dene the point of puncture [22].
Steps of state-of-the-art femoral access technique have been
previously described [23]:
• After palpation of femoral pulse and cleaning of the area,
uoroscopy is used for the identication of the lower edge
of the femoral head which is marked with the use of a
hemostat or another radiopaque material. Using a sterile
marker to mark the position of the skin so as not to miss it
later on is also encouraged (Fig.39.3a).
• The ultrasound probe is placed above the point of lower
femoral edge and moved proximally and distally in order
to detect the bifurcation of common femoral artery to
supercial and profunda femoral arteries (Fig.39.3b).
• Local anesthetic is injected subcutaneously under ultrasound guidance.
• A 18-gauge or preferably a 21-gauge needle (micro puncture needle) is advanced under ultrasound imaging
towards common femoral artery. Pulsatile blood ow
from the back end of the needle means that the needle has
entered artery’s lumen.
• A guidewire is then advanced over the needle. Fluoroscopy
will conrm optimal position of the wire.
• A sheath is then advanced over-the-wire. Usually 6–8 Fr
sheaths are used for PCI via femoral artery while in case
of micropuncture a 4 Fr sheath is initially placed, changed
then for a 6–8 Fr sheath.
• Finally, angiography is performed to conrm optimal
sheath position and antegrade ow as well as to exclude
the presence of dissection or perforation. Note that too
high sheath insertion predisposes to retroperitoneal bleed-
ab
Fig. 39.3 (a) Fluoroscopy is used in order to identify the femoral head.
The lower edge of the femoral head is marked with a hemostat. (b)
Ultrasound is then used in order to guide puncture. When both supercial and profunda femoral artery are visible the probe has been placed
under bifurcation (left panel) while when only common femoral artery
is visible the probe is above femoral bifurcation (appropriate puncture
site). Common, profunda and supercial femoral arteries are indicated
with red color while femoral vein is indicated with blue color. Reprinted
from JACC Cardiovasc Interv. Volume 10, issue 22. Sandoval Y, Burke
MN, Lobo AS, etal. Contemporary arterial access in the cardiac catheterization laboratory. Pages 2233–2241, 2017. Used with permission
from Elsevier
39 Introduction toCoronary Angioplasty
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425
ing while too low sheath insertion predisposes to
pseudoaneurysm.
The steps that are followed for gaining radial access are
similar to those previously described for femoral artery with
the exception that uoroscopy is not used before puncture.
Allen’s test is not mandatory given the results of the RADAR
trial [24]. The right radial artery is preferred with the exception of cases that LIMA has been used as a graft and has to
be engaged and of patients who have undergone transcatheter aortic valve implantation (TAVI) in the past where left
radial artery is preferred.
• The radial artery is palpated and the wrist is sterilized.
• Ultrasound is used for the localization of the radial artery.
This step is usually omitted by operators; nevertheless, in
RAUST trial, usage of ultrasound guided radial artery
cannulation improved success and efciency of the tech-
nique [25].
• Local anesthetic is administered. It is recommended to
infuse no more than 1–2mL of anesthetic in order not to
compress the artery.
• Radial artery is punctured. The optimal point of entrance is
1–2 cm distally to the radial styloid process. Two tech-
niques have been described: the anterior wall technique and
the through-and-through technique [26]. In the rst one,
the needle is inserted until back-bleeding is noticed.
Regarding the second technique, either a micropuncture
needle or a needle/catheter assembly (Angiocath) is
advanced initially through the anterior (at this point back
bleeding will be noticed) and then through the posterior
wall. Then, the micropuncture needle is withdrawn until
pulsatile bleeding from its back end is seen and a wire is
inserted. In case of Angiocath utilization, the needle is
removed and then, the catheter is carefully withdrawn until
back bleeding is pointed followed by wiring of the artery.
• A 0.018″ wire in inserted followed by removal of the
needle.
• A 4–6 Fr sheath for diagnostic angiography or a 6–7 Fr
(rarely 5 Fr) for PCI is placed.
• The dilator and the wire are removed. The sheath is
aspired, ushed and secured. A 5000IU unfractionated
heparin and 2.5 mg verapamil cocktail is administered
through the sheath in order to prevent radial artery spam
and obstruction (Fig.39.4).
Distal radial artery access (puncture of the radial artery in
the anatomic snuffbox) is an emergent technique that is very
useful when left radial artery is selected for access since it is
more comfortable for both the patient and the operator [27].
It is more demanding technically compared with the conventional transradial approach but it has been associated with a
lower rate of forearm radial artery occlusion and shorter time
of hemostasis. [28]
Fig. 39.4 Access through
the right radial artery using a
5 Fr sheath
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Coronary Artery Engagement
andAngiography
The catheters are loaded and advanced over a 0.035″ or a
0.038″ J-tip wire which should always precede when the
wire/catheter assembly is advanced in patient’s vascular system. Resistance to wire advancement can be caused by tortuosity, accidental entrance in a side branch, presence of
aneurysm, spasm or signicant stenosis/occlusion. When
resistance is felt any further effort to advance the wire should
be halted. Under uoroscopy, the catheter is advanced at the
point of resistance. After pressure recording, angiography is
performed in order to clarify the cause of resistance. If spasm
is identied, nitroglycerin and/or verapamil is administered
in the relevant artery. When tortuosity, stenosis, side branch
entrance or aneurysm is identied, a different type of wire
(such as a hydrophilic, polymer-coated or very soft tipped) is
tried. In case of a tortuous iliac artery, a long (45cm) sheath
may straighten the vessel and allow wire advancement. If all
the measures fail or complete vessel occlusion is found, an
alternative site of access should be tried.
When the wire reaches the ascending aorta, it is looped
over the aortic valve. Then, coronary arteries ostia engagement follows. Usually, the left coronary artery (LCA) is
engaged rst, followed by right coronary artery (RCA)
engagement. At posteroanterior (PA) view, the diagnostic
catheter is advanced 2–3cm over the right coronary cusp bottom and the wire is withdrawn. Usually, this movement
results in the engagement of the left main, especially when
the femoral artery is used for access. Sometimes, gentle withdrawal with slight rotation (either clockwise or counterclockwise in needed). Regarding RCA engagement, the catheter is
again advanced over the wire until it reaches the bottom of
right coronary cusp. Using a left anterior oblique (LAO) view,
the wire is then withdrawn and the catheter is rotated clockwise and withdrawn with the right hand while, at the same
time, the left hand moves the catheter back and forth [15].
Two types of catheters are used: diagnostic catheters for
diagnostic coronary angiography and guide catheters for
PCI. The main differences between them are that guide catheters have thinner walls and larger lumen in order to
accommodate the equipment that will we advanced through
them to the coronary arteries and have softer tips.
Different diagnostic catheters are used for the engagement of the LCA and RCA.The most frequently used diagnostic catheters are Judkins Left (JL) 3.5, 4, 4.5 and 5
(Fig.39.5a) and Amplatz left (AL) 1, 2 and 3 for the LCA
and Judkins right (JR) 3.5, 4 (Fig. 39.5b), Amplatz right
(AR) 1, 2, AL 1, Williams and Hockeystick for the
RCA. Jacky and Tiger are specialized catheters that have
a
c
d
b
Fig. 39.5 (a) JL 3.5 (Cordis), 5 Fr diagnostic catheter. (b) JR 4 (Cordis), 5 Fr diagnostic catheter. (c) EBU 3.5 (Medtronic), 6 Fr guide catheter.
(d) AL1 (Medtronic), 7 Fr guide catheter
39 Introduction toCoronary Angioplasty
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427
been developed for the engagement of coronary ostia via
radial access and are used for both the LCA and the
RCA.Regarding right-sided grafts, a JR 4 is used initially,
followed by multipurpose and RCB catheter in case of failure. JR 4 can also be used for left-sided grafts with AL 1 and
LCB being alternative options. The IM catheter is used for
the engagement of internal mammary arteries but JR 4 can be
tried too. Bartorelli-Cozzi catheter has been designed for the
engagement of LIMA via the left radial artery.
EBU 3.0, 3.5, 3.75, 4, 4.5 (Fig.39.5c) and XB 3.0, 3.5, 4,
4.5 guide catheters are used for LCA PCI since they provide
better support compared with JL guide catheters. Accordingly,
AL 1 (Fig. 39.5d) and 3D Right provide stronger support
compared with JR 4 guide catheter and are preferred for
complex RCA PCI.Ikari left and Ikari right are specialized
guide catheters used for LCA and RCA PCI respectively,
when the intervention is performed via radial access.
The catheter is aspired, then connected to the manifold
and the pressure tracing is checked before injection. Multiple
a
b
views of the LCA and RCA are appreciated with left, right,
cranial and caudal image receptor angulation (Fig. 39.6).
When recording cineangiograhic videos, contrast injection is
performed 1–2s after pedal pressure in order to allow enough
time for visualization of calcium or any priorly implanted
stents. Contrast should be used with caution. It is important
not to inject more than 2–3mL each time in order to avoid
excessive contrast administration that may lead to contrast
induces nephropathy. Orthogonal projections of coronary
artery segments are essential in order not to miss any stenoses. In general, > 50% stenosis in the left main and >70–90%
in the other coronary arteries are considered signicant.
Intracoronary administration of nitroglycerine (100–300μg)
is essential in order not to erroneously interpret spam as atherosclerotic stenosis. For stable CAD patients, intermediate
lesions (40–90% according to the European guidelines and
40–69% according to the American guidelines) with no prior
proof of ischemia by a stress test have to be evaluated with
fractional ow reserve (FFR) or instantaneous wave free
c
Fig. 39.6 Coronary angiography of the patient described in the introduction. Access was obtained via the right radial artery using a 6 Fr.
sheath. (a) A JL 3.5 diagnostic catheter was used for the engagement
of the left coronary artery. PA caudal view: multiple signicant lesions
in the left anterior descending coronary artery (LAD) (yellow arrows).
The rst obtuse marginal was totally occluded (circle). Subtotal
occlusion was noticed in the distal circumex (blue arrows). (b) LAO
d
e
caudal (spider) view: the left main, proximal segment of the LAD
(yellow arrow) and circumex (blue arrow) have no signicant stenoses. (c) PA cranial and (d) RAO cranial view. Multiple sequential signicant lesions in the mid-LAD (yellow arrows). (e) Right coronary
artery was engaged with a JR 4 diagnostic catheter. LAO cranial view:
subtotal occlusion of the posterior descending coronary artery (yellow
arrow)
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I. Xenogiannis
ratio (iFR). If FFR is ≤0.8 or iFr is ≤0.89, PCI is recommended (see Lesions functional assessment and
intravascular imaging) [13, 18]. TIMI (Thrombolysis in
Myocardial Infarction) ow grade should also be appreciated. Grade 0: no antegrade ow distal to the lesion. Grade 1:
contrast passes the obstruction but fails to opacify entire
coronary bed. Grade 2: contrast passes the obstruction and
opacies entire coronary bed but at a slower rate compared
with the non-culprit vessel. Grade 3: antegrade ow as fast as
in non- culprit vessel (normal ow).
In STEMI patients, the culprit vessel is the one that supplies the ischemic area as is dened by ST-segment elevation
in the corresponding ECG leads. With respect to angiographic ndings, in the context of STEMI, the culprit vessel
is most of the times totally or sub-totally occluded. Segmental
wall hypokinesis or akinesis, further assists the identication
of the culprit vessel in ACS patients. Dening the culprit vessel is more difcult in the setting of non-STEMI/unstable
angina. Most of the times the culprit lesion is found in the
proximal or mid segments of the vessels and the LAD is
more frequently the culprit vessel [29–31]. Intraluminal haziness, contrast lling defects and contrast staining are supportive of thrombus presence and along with plaque
ulceration (presence of contrast beyond the vessel lumen),
irregular plaque borders and impaired ow are angiographic
features suggestive of plaque rupture. Interestingly, more
than one stenoses may have features of unstable plaque [14].
In every patient with CAD the goal is to achieve complete
revascularization. In the setting of STEMI, the operator
should recanalize initially the culprit vessel and then should
attempt to recanalize the remaining signicant bystander
lesions either during the index procedure or in a staged manner. In STEMI patients, after culprit lesion recanalization,
CABG should be considered in the presence of remaining
complex multivessel disease that complete revascularization
is unlikely to be achieved with PCI. Likewise, in patients
with non-STEMI or stable CAD complete revascularization
can be attempted at a single operation or in a staged manner.
CABG is favored over PCI in cases of three-vessel disease
(especially with SYNTAX score>22), three-vessel disease
in diabetic patients, left main disease with SYNTAX
score>32, multivessel disease with ejection fraction ≤35%
and whenever it is believed that the anatomy is not amenable
to complete revascularization with PCI [13].
Wiring
Guidewires are 0.014in wires made by stainless steel or nitilon that are used in order to cross the target lesion. They use
as a rail over which balloons and stents are advanced
(Fig.39.7a). The rst step of wiring is to select the appropriate guidewire. For non-complex lesions, a workhorse guide-
wire is the rst option. The characteristics of workhorse
guidewires are that they have a soft tip that is usually less
than 1 g and are not polymer-jacketed. Some of the most
commonly used workhorse guidewires worldwide (i.e. Sion
Blue [Asahi Intecc] and Samurai [Boston Scientic]) have
hydrophilic coating that spares their tip in order to navigate
easier through tortuous vessels and at the same time be safer
than hydrophilic guidewires. Hydrophilic (hydrophilic covering of either the tip or multiple cm of the guidewire) and
polymer-jacketed guidewires (covered by slippery polymer,
such as Fielder-XT [Asahi Intecc], Sion Black [Asahi Intecc],
Pilot 200 [Abbott Vascular]) have better deliverability
through tortuous vessels compared with non-hydrophillic
workhorse guidewires, however, it is more likely to injure the
coronary artery causing either perforation or dissection.
Polymer-jacketed guidewires are especially useful for the
crossing of CTOs.
Before the insertion of the guidewire to the catheter and
the coronary artery, its tip has to be shaped. Some guidewires
have a preshaped tip so there is no need for shaping but, on
the other hand, they leave less exibility to the operator. In
general, larger vessels require big bends while smaller vessels require small bends. For some lesions, more than one
bend is needed for successful crossing. The guidewire is then
advanced into the catheter through the hemostatic valve and
then, under uoroscopy, into the coronary artery. For advancing the guidewire through the left main to the ostium of LAD
or circumex, caudal views are preferred. Then for navigating into the LAD, a right anterior oblique (RAO) cranial or
PA cranial view is used. With respect to the RCA, initially a
LAO view is used, changed for a LAO or PA cranial view for
wiring through the posterior descending artery or posteriolateral branch.
The wire is advanced using a torque. For guidewire
advancement, the combination of a forward movement/pushing (and backward/withdrawing when the wire has accidentally entered a side branch) with simultaneous rotation is
used. Various techniques have been applied: many operators
prefer to do both movements with one hand while others prefer to move forward and backward the guidewire with their
left hand and at the same time rotating it with the torque
using the right hand. It should be noted that the nal few cm.
(usually 3) of the guidewires are radiopaque allowing better
visualization of the tip and estimation of lesion’s length
when it is crossed. If a lesion is resistant to crossing, change
of the wire’s tip or using a more advanced (hydrophilic or
polymer-jacketed) guidewire usually solves the problem. For
the most complex subsets of lesions and especially for CTOs,
the use of a microcatheter is essential. Microcatheters (such
as Corsair, Caravel and Turnpike) are small catheters with
distal shaft outer diameter ranging from 1.8 to 3.2Fr that are
advanced over the guidewire and through the guide catheter
into the coronary artery. They provide better support enhanc-
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