Transcript Ischemic heart disease

Ischemic heart disease
Basic Science 3/15/06
All of the following concerning coronary artery
anatomy are correct except:
 The left main coronary artery rises from the left
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coronary sinus and bifurcates into the left anterior
descending (LAD) and the left circumflex (LCA)
coronary arteries.
The LAD supplies the anterior and left lateral portions
of the left ventricle.
The LAD also supplies perforating branches to the
posterior interventricular septum.
Left or right sided dominant circulation is determined
by the vessel supplying the PDA.
In approximately half of patients, the pattern of
circulation is right dominant.
All of the following concerning coronary artery
anatomy are correct except:
 The left main coronary artery rises from the left
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coronary sinus and bifurcates into the left anterior
descending (LAD) and the left circumflex (LCA)
coronary arteries. T
The LAD supplies the anterior and left lateral portions
of the left ventricle. T
The LAD also supplies perforating branches to the
posterior interventricular septum. F, anterior portion.
Left or right sided dominant circulation is determined
by the vessel supplying the PDA. T
In approximately half of patients, the pattern of
circulation is right dominant. F, ~ 90% of patients
have a right dominant circulation, with the PDA
supplied by the RCA.
Which of the following statements is true
regarding the morphologic features of coronary
artery disease?
 Most acute myocardial infarctions result from
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coronary occlusion secondary to hemorrhage within a
plaque.
Complete occlusion of one coronary artery is
uncommonly associated with significant lesions in
other coronary arteries
The LAD and RCA systems are more commonly
involved than the circumflex system.
Transmural infarctions are characterized by complete
absence of viable myocardial cells in the infarct area.
Acute infarcts usually occur in chronic, severely
narrowed vessels.
Which of the following statements is true
regarding the morphologic features of coronary
artery disease?
 Most acute myocardial infarctions result from coronary
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occlusion secondary to hemorrhage within a plaque. F,
result from plaque rupture and thrombotic occlusion
Complete occlusion of one coronary artery is uncommonly
associated with significant lesions in other coronary
arteries. F, 95% of patients with 1 completely occluded
artery will have a significant stenosis in at least one other
artery.
The LAD and RCA systems are more commonly involved
than the circumflex system. T
Transmural infarctions are characterized by complete
absence of viable myocardial cells in the infarct area. F,
most such infarcts have islands of viable myocardial cells.
Acute infarcts usually occur in chronic, severely narrowed
vessels. F, often have developed collaterals resisting
infarction.
High risk or vulnerable plaques have all of the
following characteristics except:
 Typically are large, eccentric with a large intralipid
core.
 Posses a thin , weak, fibrous cap that is prone to
rupture.
 Evidence of active inflammation within the cap and
adjacent adventitia.
 Decreased plaque neovascularity resulting in
necrosis and weakening of plaque.
High risk or vulnerable plaques have all of the
following characteristics except:
 Typically are large, eccentric with a large intralipid
core. T
 Posses a thin , weak, fibrous cap that is prone to
rupture. T
 Evidence of active inflammation within the cap and
adjacent adventitia. T
 Decreased plaque neovascularity resulting in
necrosis and weakening of plaque. F, increased
neovascularity enhances risk of rupture.
Which of the following statements is true
regarding the natural history of CAD?
 A patient successfully treated for an episode of
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unstable angina does not have a worsened
prognosis.
Infarct size has a poor correlation with early mortality
after myocardial infarction.
Use of thrombolytics has lowered hospital mortality
after acute MI to less than 10%.
Most patients with significant CAD die from chronic
heart failure.
Sudden death is uncommon in untreated CAD.
Which of the following statements is true
regarding the natural history of CAD?
 A patient successfully treated for an episode of
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unstable angina does not have a worsened
prognosis. F, less favorable prognosis. Up to 40% of
patients will suffer an acute myocardial infarction
within 10 years.
Infarct size has a poor correlation with early mortality
after myocardial infarction. F, <40% infarcted LV
mass results in mortality of ~ 50%.
Use of thrombolytics has lowered hospital mortality
after acute MI to less than 10%. T, ~ 7%
Most patients with significant CAD die from chronic
heart failure. F, from acute heart failure or ventricular
arrhythmias.
Sudden death is uncommon in untreated CAD. F,
~20%
Which of the following statements is true
regarding myocardial ischemia?
 Myocardial stunning refers to reversible myocardial
dysfunction lasting several days due to short term
(15-20 minute) ischemia.
 The incidence of myocardial stunning in pts after
CABG is on order of 5-10 %.
 Irreversible myocardial injury or infarction is
associated with ischemia lasting 20+ minutes.
 Myocardial infarction generally leads to an
inflammatory process with migration of PMN to site
with removal of debris by macrophages.
Which of the following statements is true
regarding myocardial ischemia?
 Myocardial stunning refers to reversible myocardial
dysfunction lasting several days due to short term
(15-20 minute) ischemia. T
 The incidence of myocardial stunning in pts after
CABG is on order of 5-10 %. F, 20 – 80%.
 Irreversible myocardial injury or infarcation is
associated with ischemia lasting 20+ minutes. T
 Myocardial infarction generally leads to an
inflammatory process with migration of PMN to site
with removal of debris by macrophages. T
Which of the following are considered when
selecting conduits for CABG?
 Internal thoracic arteries are preferred due to their
patency rates exceeding 90% at 10 years.
 Diabetics are ideal candidates for ITA use due to the
lower rates of infection.
 The most commonly used conduit is the greater
saphenous vein.
 Vein graft patency rates are equivalent to arterial
graft patency.
Which of the following are considered when
selecting conduits for CABG?
 Internal thoracic arteries are preferred due to their
patency rates exceeding 90% at 10 years. T
 Diabetics are ideal candidates for ITA use due to the
lower rates of infection. F, bilateral ITA mobilization is
associated with 14x greater risk of sternal infections
in diabetics.
 The most commonly used conduit is the greater
saphenous vein. T
 Vein graft patency rates are equivalent to arterial
graft patency. F, patency rates have been reported to
be 88% early after grafting, 81% at 1 year, 75% at 5
years, and 50% at 15 years; ITA patency at 10 years
exceeds 90%.
Indications for CABG vs other modalities
include all of the following except:
 Patients with stable angina can safely undergo PTCA
as a first intervention for CAD.
 CABG surgery confers a superior long-term survival
benefit in patients with specific anatomic lesions and
is associated with an increased freedom from angina,
a significant reduction in antianginal medications, and
fewer subsequent PCIs.
 CABG surgery is the treatment of choice in diabetic
patients.
Indications for CABG vs other modalities
include all of the following except:
 Patients with stable angina can safely undergo PTCA
as a first intervention for CAD. T
 CABG surgery confers a superior long-term survival
benefit in patients with specific anatomic lesions and
is associated with an increased freedom from angina,
a significant reduction in antianginal medications, and
fewer subsequent PCIs. T
 CABG surgery is the treatment of choice in diabetic
patients. T, despite some limitations (study done
before widespread use of stents and plavix), CABG
appears to confer a survival benefit to diabetic
patients that is superior to angioplasty.
Which of the following statements is true
regarding CAB outcomes?
 Ventricular arrhythmia is the most common ischemic
event after CAB.
 Preoperative ejection fraction has no correlation with
postoperative incidence of sudden death.
 Both maximal exercise capacity and functional
capacity are improved by CAB.
 Only hypokinetic areas can be expected to have
improved systolic function after surgery.
Which of the following statements is true
regarding CAB outcomes?
 Ventricular arrhythmia is the most common ischemic
event after CAB. F, The most common ischemic
event after CAB is the return of angina. Myocardial
infarction is uncommon after CAB, with less than 5%
of patients suffering an MI in the first 5 years.
 Preoperative ejection fraction has no correlation with
postoperative incidence of sudden death. F, Poor
preoperative LV function is the most significant risk
factor for sudden death after CAB.
 Both maximal exercise capacity and functional
capacity are improved by CAB. T
 Only hypokinetic areas can be expected to have
improved systolic function after surgery F,
Hypokinetic, akinetic, and even dyskinetic areas can
show improved systolic function after CAB.
Acute Coronary Artery Syndrome is
characterized by:
 Characterized by a constellation of clinical conditions
that reflect acute myocardial ischemia (AMI).
 Congestive heart failure is the usual cause of early
death.
 Categories include unstable angina, non–STelevation myocardial infarction (NSTEMI), and STelevation myocardial infarction (STEMI).
 Of those suffering from AMI, 10-15% will die, and half
of these patients do so within an hour after onset of
symptoms.
Acute Coronary Artery Syndrome is
characterized by:
 Characterized by a constellation of clinical conditions
that reflect acute myocardial ischemia (AMI). T
 Congestive heart failure is the usual cause of early
death. F, arrhythmias, usually ventricular fibrillation,
are the cause of early death.
 Categories include unstable angina, non–STelevation myocardial infarction (NSTEMI), and STelevation myocardial infarction (STEMI). T
 Of those suffering from AMI, 10-15% will die, and half
of these patients do so within an hour after onset of
symptoms. T
Which of the following have been deemed core
risk factors for CAGB surgery?
 Ejection fraction.
 Age.
 Elevated serum creatinine levels.
 Prior heart surgery.
 Presence of Left Main coronary disease.
 Severity of CAD.
Which of the following have been deemed core
risk factors for CAGB surgery?
 Ejection fraction. T
 Age. T
 Elevated serum creatinine levels. T/F, less predictive
but still a level 1 risk factor.
 Prior heart surgery. T
 Presence of Left Main coronary disease. T
 Severity of CAD. T