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 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 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

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

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 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 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–ST-elevation myocardial infarction (NSTEMI), and ST-elevation 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–ST-elevation myocardial infarction (NSTEMI), and ST-elevation 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