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Coronary anatomy (view source)

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Patients with older age, diabetes mellitus, chronic renal insufficiency, multivessel disease, low ejection fraction have a higher risk of complications.
Patients with older age, diabetes mellitus, chronic renal insufficiency, multivessel disease, low ejection fraction have a higher risk of complications.


=Time-out procedure=
In surgery, the use of a pre-operative checklist has improved the outcome. Implementation of a 19-item surgical safety checklist improved team communication and reduced rates of death and complications in patients undergoing noncardiac surgery<cite>Haynes</cite>. Implementation of a comprehensive preoperative checklist targeting the entire surgical pathway (including items such as medication, marking of operative side and the use of postoperatieve instructions) was associated with a reduction in surgical complications and mortality in hospitals with a high standard of care<cite>deVries</cite>.
Although the goal of most procedures in interventional cardiology is to access the heart and its associated vasculature (making wrong site procedures less of a concern), a preprocedure checklist is also recommended in the catheterization laboratory<cite>Naidu</cite>. Information obtained preprocedural should include procedural indication, patients history, informed consent, a review of medication (in particular antiplatelet therapies and metformin) and a risk of bleeding assessment. Renal function should be less than 90 days old. If the patient is using VKA an INR is obtained < 24 preprocedural.  Images of prior catheterizations are obtained and procedural reports of any coronary or peripheral bypass surgery reviewed. The history should be reviewed for previous heparin-induced thrombocytopenia (HIT). Allergies should be checked, especially contrast allergies or allergies to medication used periprocedural (p.e. heparin). Each laboratory has a protocol for preventing contrast allergic reaction (using p.e. Prednison and an antihistaminic).
Before procedure a time-out procedure is performed by all team members before vascular access is obtained. Patient identification should be checked and confirmed and agreement on the right procedure obtained. Figure 1 shows a sample of a time-out checklist.
Figure 1
<br/>
Sample ‘‘Time Out’’ Preprocedure Checklist
The physician taking ultimate responsibility for the procedure should lead the Time Out and ensure each of the following items is announced:
#Patient’s name and medical record number
#Procedure to be performed (e.g., left heart catheterization, coronary angiography, right heart catheterization)
#Route to be used (e.g., right femoral artery)
#Confirm that the equipment needed is available or alternatives are available including intended stent type for PCI or cath-possible patients
#Patient’s allergies and premedication if appropriate (e.g., heparin-induced thrombocytopenia, contrast allergy)
#Special laboratory or medical conditions (e.g., elevated INR, chronic kidney disease)
=Vascular Access Site=
=Vascular Access Site=
Before Judkins developed the percutaneous transfemoral approach in the late sixties, brachial arteriotomy was performed to introduce the catheter. This is seldomly used nowadays. In the majority of cases arterial catheters are introduced via the femoral artery or radial artery using the Seldinger technique.
Before Judkins developed the percutaneous transfemoral approach in the late sixties, brachial arteriotomy was performed to introduce the catheter. This is seldomly used nowadays. In the majority of cases arterial catheters are introduced via the femoral artery or radial artery using the Seldinger technique.
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*LAO 20 cranial 25                      Crux, RDP and RPL
*LAO 20 cranial 25                      Crux, RDP and RPL


[[File:RecommendedRadiographicProjections.png]]
[[File:RecommendedRadiographicProjections_03072014.png]]
LAO 45
LAO 45


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For collateral connections, it is necessary to make longer angiographic projections. In a RCA obstruction, intercoronary collaterals can form between the septal branches of the LAD and the RDP through the interventricular septum. Collaterals connecting distal portions of two arteries are frequently observed, p.e. connections between the distal RCx and RCA in the interventricular groove and between diagonal branches of the LAD. A collateral between the conus branch of the RCA to the proximal LAD is called a ring of Vieussens. Atrial branches from the RCA or the Kugel’s artery (mostly an small artery arising from proximal RCA anastomosing with branches of sinus node artery) can form connections between the proximal and distal RCA.
For collateral connections, it is necessary to make longer angiographic projections. In a RCA obstruction, intercoronary collaterals can form between the septal branches of the LAD and the RDP through the interventricular septum. Collaterals connecting distal portions of two arteries are frequently observed, p.e. connections between the distal RCx and RCA in the interventricular groove and between diagonal branches of the LAD. A collateral between the conus branch of the RCA to the proximal LAD is called a ring of Vieussens. Atrial branches from the RCA or the Kugel’s artery (mostly an small artery arising from proximal RCA anastomosing with branches of sinus node artery) can form connections between the proximal and distal RCA.


=Left ventriculography=
Left ventriculography provides information about global and segmental left ventricular function and mitral regurgitation, and some other abnormalities (ventricular septal defect, hypertrophic cardiomyopathy, left ventricular thrombi)<cite>Baim</cite>.
''Technique''
<br/>
The large amount of contrast that is needed in short time, is delivered by a pigtail catheter with multiple side holes. The RAO 30° projection is used without magnification. The catheter is placed on the aortic valve with a guidewire, retracted a few centimeters in the catheters. After pushing the pigtail on the valve until bending, it is retracted slowly while being rotated clockwise, untill passing into the left ventricle (figure 1<cite>Hartcatheterisatie</cite>). The optimal catheter position is midcavitary. About 35 ml of contrast is delivered at 10ml/second at a PSI of maximal 1000 at RAO 30° and LAO 60°. Left ventriculography can be performed with normal quiet breathing (in LAO, the diaphragm can be obstructive during expiration).
''Interpretation''
<br/>
The left ventriculogram is analysed qualitatively on a sinus beat following a previous sinus beat since ectopic of postectopic beats give a false impression of ventricular function. Overall ventricular function is described. In RAO view, the anterolateral, apical, inferior and posterobasal segment can be seen, in LAO view the posterolateral, lateral and septal segments (figure 1). The degree of mitral regurgitation can be estimated.
''Complications''
<br/>
It is normal for the patient to experience a hot feeling due to powerful vasodilatation of the contrast. Ventricular extrasystoles occur frequently but also ventricular tachycardia or ventricular fibrillation can occur. The pigtail can be placed under chordae (catheter close to inferior wall). If it is placed under the papillary muscles with a side hole firmly against the endocardium, deposition of contrast material within the endocardium and myocardium can occur, leading rarely to myocardial perforation. A possible complication that can lead to death is the injection of air (air embolism). If the catheter is placed in the left ventricular outflow tract, a left anterior fascicular block can occur, leading to complete heart block in pre-existing right bundle branch block and left posterior fascicular block.
<br/>
Figure 1
<br/>
[[File:TimeOut_figure1.png]]
Figure 2
<br/>
[[File:TimeOut_figure2.gif]]
#Anterobasal
#Anterolateral
#Apical
#Inferior
#Posterobasal
#Posterolateral
#Lateral
#Septal
Figure 3
<br/>
[[File:TimeOut_figure3.gif]]
Left ventriculography during systole showing apical ballooning akinesis with basal hyperkinesis in a patient with takotsubo cardiomyopathy.
=Shock=
Cardiogenic shock is the inability of the heart, as a result of impairment of its pumping function, to deliver sufficient blood flow to the tissues to meet resting metabolic demands<cite>Califf</cite>. There is poor cardiac output and evidence of tissue hypoxia in the presence of adequate intravascular volume. The diagnosis is indicated by low blood pressure (<90mm Hg, or <30mm Hg below basal levels), a depressed cardiac index (< 2.2 L/min) in the presence of an elevated pulmonary-capillary wedge pressure (> 15 mmHg).
Causes of cardiogenic shock are:
*Acute myocardial infarction (left or right)
*Mechanical complication
**Acute mitral regurgitation due to papillary muscle dysfunction or rupture
**Ventricular septal rupture
**Free-wall rupture
**Left ventricular aneurysm
*Other causes
**Myocarditis
**Mycoardial contusion
**Left ventricular outflow tract obstruction (aortic stenosis, hypetrophic obstructive cardiomyopathy)
**Left ventricular inflow tract obstruction (mitral stenosis, intracardiac tumour)
**After cardiopulmonary bypass
=Intra-aortic balloon counterpulsation=
''Background''
<br/>
The intra-aortic balloon pump (IABP) was first introduced in 1968<cite>Kantrowitz</cite>. It uses counterpulsation to increase aortic pressure during diastole and decreasing aortic pressure during systole. This improves the artery blood supply while decreasing the impedance for blood from the ventricle during systole<cite>Baim2</cite>.
[[File:IntraAortic_figure1.jpg]]
<br/>
Figure 1: intra-aortic location of IABP


[[File:IntraAortic_figure2.jpg]]
<br/>
Figure 2: balloon pressure curve.
''Technique''
<br/>
The balloon pump system consists of a balloon-tipped catheter (polyurethane, 10cm, 40ml, dual lumen) that is positioned in the descending aorta 1 to 2 cm beyond the origin of the left subclavian artery and is inserted percuteaneously through a 8-9 French sheath. The balloon is inflated in with helium after aortic valve closure (triggered on the R wave of surface ECG), and maintained until just before the beginning of systolic ejection when the helium is abruptly withdrawn. When appropriately timed, the effect of the IABP is to reduce ventricular afterload and increase cardiac output.
''Indication''
<br/>
Indication for IABP:
*Cardiogenic shock secondary to myocardial infarction with continuing ischemia, ventricular septal rupture or mitral regurgitation, myocarditis, sepsis (IIb indication in ESC STEMI guideline<cite>EurHeart</cite>)
*Inability to wean from bypass after cardiac surgery
*Severe arrhythmia owing to refractory ischemia
*Prophylactic high risk intervention (high risk PCI due to LV dysfunction or large territory at risk, severe multivessel disease, left main disease)
Contra-indications are:
*Significant aortic regurgitation
*Abdominal aortic aneurysm
*Aortic dissection
*High risk of bleeding
*Bilateral femoral-popliteal bypass grafts
''Precautions''
<br/>
The level of anticoagulation should be monitored daily, with aPTT maintained 50-70 seconds to prevent thrombotic or embolic complications. Evalutions of the limbs and peripheral circulation should be checked regularly. Before removal, patients are weaned by decreasing the counterpulsation (to 1:2/1:3). The incidence of major complications is 2.8%. Common complications are limb ischemia, access site bleeding and balloon leak. Risk factors for complications are female sex, older age (>75 years), BSA < 1.65m2 and peripheral vascular disease.
''Clinical results''
<br/>
In one meta-analyses including 7 randomized trials with STEMI patients with cardiogenic shock, IABP showed neither a 30-day survival benefit nor improved left ventricular ejection fraction, and was associatied with more complications (higher stroke, higher bleeding rates). Another meta-analysis included 9 cohorts with STEMI patients with cardiogenic shock, and showed that IABP was associated with an 18% decrease in 30 day mortality, but with significantly higher revascularization rates and higher mortality in the PCI group<cite>EurHeart2</cite>.  In the randomized controlled trial Shock II, publiced in the NEJM in 2012, the use of IABP did not significantly reduce the 30-day mortality in patients with cardiogenic shock complicating acute myocardial infarction for whom an early revascularization strategy was planned<cite>Thiele</cite>.
= Other circulatory assist devices: Impella =
The Impella device is an axial flow pump on a catheter.  The system has an electromagnetic motor directy coupled to a helical impeller located near the tip of a catheter. When the “snorkel” at the tip of the catheter is placed across the aortic valve and into the left ventricular chamber, the motor rotates the impeller at 50.000 rpm, drawing ventricular blood into the distal end of the catheter and discharging it non-pulsatile into the ascending aorta. The device can be placed via the femoral artery in a 9 Fr sheath. There are 2 versions: a 2.5 and a 5L (33.000 rpm), with maximal outputs of respectively 2.5 and 5.0L/min. Before placement an echocardiography should rule out LV thrombus<cite>Engstrom</cite>.
Possible indications for Impella placement are high risk PCI and cardiogenic shock.
In 2012, the PROTECT II trial randomized 452 patients with 3-vessel of left main coronary artery disease and severely depressed left ventricular function to an Impella (2.5L) or an IABP. The Impella provided superior hemodynamic support, but with no difference in the 30 days endpoint of major adverse events<cite>Cardiol</cite>.
In 2008, a multicenter registry showed the Impella 2.5 to be safe and potentially useful in hemodynamic support in high-risk PCI (multivessel, left main, last remaining vessel, low LV function) with rates of myocardial infarction, stroke, bleeding and vascular complications at 30 days of 6.2%<cite>Oneill</cite>.
[[File:Impella.jpg|thumb|400px|Example of a 2.5L Impella system<cite>McCulloch</cite>]]
<br/>


= References =
= References =
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#Jukema4 Jukema JW, Vliegen HW, Bruschke AVG. Coronary angiography: principles, technique and interpretation. 1e druk, Leiden, the Netherlands, 2009. Chapter 3: 23-34.
#Jukema4 Jukema JW, Vliegen HW, Bruschke AVG. Coronary angiography: principles, technique and interpretation. 1e druk, Leiden, the Netherlands, 2009. Chapter 3: 23-34.
#Jukema5 Jukema JW, Vliegen HW, Bruschke AVG. Coronary angiography: principles, technique and interpretation. 1e druk, Leiden, the Netherlands, 2009. Chapter 4: 35-40.
#Jukema5 Jukema JW, Vliegen HW, Bruschke AVG. Coronary angiography: principles, technique and interpretation. 1e druk, Leiden, the Netherlands, 2009. Chapter 4: 35-40.
#Haynes pmid=19144931
#deVries pmid=21067384
#Naidu pmid=22434598
#Baim Baim DS. Grossman’s cardiac catheterization, angiography, and intervention. 7th edition 2006. Lipincott Williams & Wilkins, Philadelphia PA USA. Chapter 12: 222-233.
#Hartcatheterisatie https://www.mst.nl/opleidingcardiologie/modules/hartcatheterisatie/
#Califf pmid=8190135
#Kantrowitz pmid=5694059
#Baim2 Baim DS. Grossman’s cardiac catheterization, angiography, and intervention. 7th edition 2006. Lipincott Williams & Wilkins, Philadelphia PA USA. Chapter 21: 412-430.
#EurHeart pmid=22922416
#EurHeart2 pmid=19168529
#Thiele pmid=22920912
#Engstrom pmid=21118589
#Cardiol pmid=20082934
#Oneill pmid=22935569
#McCulloch  pmid=21285459
</biblio>
</biblio>
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