Transcript Surgery of Coronary Artery Disease

Surgery of Coronary Artery
Disease
Ischemic Heart Disease
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IHD – imbalance between myocardial
oxygen demand and supply:
Coronary Artery Disease
Printzmetal Angina
Syndrome X
Coronary Artery Disease
(CAD)
Deficiency in blood supply to
myocardium caused by stenotic
atheromatous lesions in major
branches of coronary arteries
Clinical Forms of CAD
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Stable Angina
Unstable Angina
Acute Coronary Syndrome
Myocardial Infarction
Ischemic Myocardiopathy (Left Ventricular
Remodeling, Mitral Regurgitation)
Prevalence of CAD
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About 50% of total mortality in Europe
and North America is due to
cardiovascular diseases
100.000 of Acute Myocardial Infarctions in
Poland each year
The older population the more prevalent
CAD
Complex Etiology of Atheromatosis
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Genetic (family history)
Metabolic (hyperlipidemia, diabetes)
Life Style (obesity, smoking, lack of
exercise)
Infectious and Inflammatory?
Risk Factors of CAD
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Sex - male
Age - older
Family History
Arterial Hypertension
Hyperlipidemia
Smoking
Obesity
Symptoms of CAD (1)
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Angina – retrosternal chest pain, usually
related to the exercise
Canadian Cardiovascular Society (CCS)
Classification of Angina:
I class – only in extreme exercise
II class – in moderate exercise
III class – in every exercise
IV class – also in rest
Symptoms of CAD (2)
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Dyspnea (in Ischemic Myocardiopathy or
Mitral Regurgitation)
New York Heart Association (NYHA)
classification of dyspnea (I-IV class)
When NYHA class higher than CCS class –
poor prognosis
Pathology of CAD (1)
Atheromatous Plaque
Stable
(fibrous)
Stable Angina
Unstable
(ulceration + thrombus)
Unstable Angina
Acute Myocardial Infarction (AMI)
(necrosis)
Pathology of CAD (2)
Complications of CAD
Chronic ischemia –
AMI -necrosis
-fibrosis
LV Remodeling
Pump failure
Cardiomyopathy
Mitral Regurgitation (MR)
Rapture of myocardium
Cardiogenic Shock
Acute VSD
Acute MR
Tamponade (free wall)
Pathophysiology of CAD
Consequences of Coronary Artery Stenosis:
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Up to
About
More than
100%
50% - asymptomatic
75% - exercise angina
90% - rest angina
- AMI
Diagnostics of CAD
Methods
History
Angina (CCS)
Risk Factors
Non-invasive
ECG
Rest
Exercise
24-hours
Echocardiography
Invasive
Coronary
Angiography
Evidence taken from Exercise ECG
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Clinically positive (angina)
ECG positive (ST segment abnormalities)
localization: anterior, lateral, posterior
Exercise tolerance (in METs*)
* MET – metabolic equivalent – rest
oxygen demand = 30 ml/kg/min
Evidence taken from
Echocardiography
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Global systolic function of left ventricle –
left ventricular ejection fraction (LVEF):
Good
 Moderately impaired
 Poor
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– LVEF>50%
–LVEF 30-50%
–LVEF<30%
Regional systolic abnormalities
(hypokinesis, akinesis, dyskinesis)
Mitral Regurgitation
Indications for Coronary
Angiography
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Typical Angina (even with negative ECG
exercise test)
Positive ECG exercise test
Unstable Angina / Acute coronary
syndrome (primary rescue PCI)
After Myocardial Infarction especially when
angina persists
Technique of Coronary Angiography
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Selective coronary artery catheterization
via femoral or radial artery
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Administration of iodine contrast
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X-ray motion picture
Evidence taken from Coronary
Angiography
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Presence of lesions in coronary arteries
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Degree of stenosis (0-100%)
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Localization of lesions (proximal or distal)
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Type of lesions (A, B or C)
What is a significant stenosis of
coronary artery?
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Left main stem (LMS) stenosis of 50% or
more
Other vessels stenosis of 75% or more
Clinical Value of Coronary
Angiography in Decision Making
Evidence of CAD
Medical
Treatment
Invasive
Cardiology
PCI
Surgical
Treatment
Invasive Cardiology or Surgery?
The most important disadvantage of PCI is still high rate of
re-stenosis, reaching 30% per year (10% using DES)
CAD
INVASIVE:
Acute coronary syndrome
One- or two- vessels disease
Type A lesions
Good LV function
Non-diabetics
SURGERY:
LMS stenosis
3-vessels disease
Poor LV function
Diabetics
Anatomy of
Coronary
Arteries
Anatomy of Left Coronary Artery
Left Main Stem
LMS
Left Anterior Descending
LAD
Circumflex
Cx
Diagonal Branches
Dg1, Dg2 etc.
Marginal Branches
Mg1, Mg2 etc.
Anatomy of Right Coronary Artery
Right Coronary Artery
RCA
Right Posterior Descending
RPD
Postero-Lateral
PL
The Milestones of Coronary Surgery
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1959
1964
1967
1991
Sonnes
Kolesov
Coronary angiography
Graft:LITA-LAD (no
CPB, no Angiography)
Favaloro CABG
Benetti OPCAB
Idea of Surgical Treatment of CAD
Revascularization of the heart via bypassing significantly narrowed coronary
arteries to enhance blood supply to
ischemic regions of myocardium
The Goals of Surgery in CAD
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To prolong a lifetime
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To improve a quality of living
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To prevent myocardial infarction and its
complications
Surgical Revascularization
Procedures
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Coronary Artery By-Pass Grafting (CABG) CLASSIC
Off-Pump Coronary Artery By-Pass
(OPCAB) – NO CPB
Minimally Invasive Coronary Artery ByPass (MID-CAB) – NO STERNOTOMY
Transmural Laser Revascularization
(TMLR) - ALTERNATIVE
CABG – The Classic Coronary
Operation
Since 1967 when Favaloro from Cleveland
Clinic in USA performed the first CABG it
has become one of the most popular
surgical procedure in the world
CABG or OPCAB?
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The biggest advantage of OPCAB is avoidance of
complications related to CPB e.g. SIRS and
slightly lower costs
However, OPCAB provides less completeness of
revascularization and worse precision of
anastomosis (moving operating area)
Classic indication for OPCAB is isolated stenosis
of LAD not suitable for PCI e.g. amputation
OPCAB
Cardio-Pulmonary Bypass (CPB)
Cardio-Pulmonary By-Pass (CPB)
Extracorporeal circulation (ECC)
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Requires full heparinization of the patient
Main elements:
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System of cannules, tubes and filters
Oxygenator
Pumps (arterial and suction)
Side effects
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Blood cells damage
Systemic Inflammatory Response Syndrome (SIRS)
Indications for CABG
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Left main stem stenosis > 50%
Equivalent of LMS stenosis (proximal stenosis of
LAD and Cx > 75%)
Three-vessels disease (stenoses of RCA, LAD
and Cx or their branches >75%)
Proximal LAD stenosis >75% with one- or twovessels disease, with excessive part of
myocardium in jeopardy, especially in patients
with poor LV function and/or in diabetics (not
suitable for PCI, method of choice if isolated–
OPCAB)
Counter-indications for CABG
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Acute myocardial infarction (2 weeks)
Use of antiplatelet drugs like ticlopidine or
clopidogrel (2 weeks or platelet
concentrate – if emergency)
Lack of graftable distal vessels (diameter
of at least 1,5mm) – consider TMLR
Scheduled or emergency CABG?
When to operate?
Stable
Scheduled
Weeks
Asymptomatic LMS
Urgent
Days
Unstable
Emergency
Hours
Patient’s Preparation to Scheduled
CABG
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Red cells concentrate (autotransfusion, family
donations)
Coagulometry
Cessation of antiplatelet drugs (2 weeks before
surgery)
Optimal medical treatment (beta-blockers,
statins, control of glycemia in diabetics)
Co-morbidities (carotid doppler, gastroscopy)
Predictors of Outcomes after CABG
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Age > 60 years
Female sex
Poor LV function
Re-do operation
Emergency
Obesity
Co-morbidities
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Renal failure
Chronic Obturatory Pulmonary Disease
Stroke
Generalized atherosclerosis
CABG-Technique
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Medial Sternotomy
Use of CPB
Saphenous by-pass grafts (SBG) or arterial
grafts
Material for Grafts in CABG
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Saphenous vein (SBG)
Left internal thoracic artery (LITA)
Right internal thoracic artery (RITA)
Radial artery (RA)
Gastroepiploic artery
Venous or arterial grafts?
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Arterial grafts are generally better than venous –
e.g. LITA patency rate after 20 years is 90%
whereas 50% of SBGs is occluded after 10
years.
GOLDEN STANDARD: LITA to LAD!
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Totally arterial revascularization is especially
indicated in young patients and in those with
bilateral crural varicosity
CABG
Venous
grafts
Venous
sequential
graft
Harvested
LITA
Graft: LITA
to LAD
Harvesting and anastomosing of
Radial Artery
Outcomes of CABG
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Mortality rate 1-5% - depends mostly of
patients’ profile (see predictors of
outcomes )
Common postop. complications:
Excessive bleeding, heart tamponade
Perioperative myocardial infarction - low cardiac output
Stroke or psycho-organic syndromes
Acute renal failure
Hemothorax, pneumothorax
Sternal dehiscence, mediastinitis
Typical uncomplicated course after
CABG
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ICU 1-2 days:
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Hospital stay – about 1 week
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Artificial ventilation <12 hours
Chest tubes – 2 days
Antibiotics – 4 days
Rehabilitation 2-3 weeks
Most of the patients returns to normal
activity in few months
Standard Medication after CABG
„A B S”
ASA 150-300 mg daily
 Beta-Blockers
 Statins
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Secondary Prevention after CABG
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Lipids control
Glucose control
Weight control
Arterial pressure control
Smoking cessation
Moderate exercise