Conduction Disorders and Other MI Complications Flashcards
Question 1 of 8
John, age 58, has presented in the emergency department complaining of severe chest pain. He states that two nitroglycerin tablets did not alleviate his pain. An electrocardiogram (ECG) is immediately ordered, along with serum laboratory values for cardiac markers.
John’s ECG revealed a 4-mm ST segment elevation in V2–V6. Which of the following best describes John’s condition? NSTEMI STEMI Partial occlusion of coronary artery Stable angina
STEMI
The ST segment elevation indicates John is experiencing an ST elevation myocardial infarction (STEMI) event, not a non-ST elevation myocardial infarction (NSTEMI), in which no ST segment elevation would be apparent. A STEMI indicates complete, not partial, occlusion of a coronary vessel. The fact that John’s pain was not relieved with nitroglycerin shows it is not stable angina.
Question 2 of 8
Coronary angiography reveals significant blockage in the coronary artery serving the anterior/inferior left ventricle. Which artery is occluded? Left anterior descending Circumflex Posterior interventricular Right marginal
Left anterior descending
The left anterior descending (LAD) serves as the artery for the left ventricle (LV), particularly the anterior and inferior portions of the LV. The other arteries listed serve different portions of the heart, including the posterior aspect (posterior interventricular), right ventricle (right marginal), and left side of heart (circumflex).
Question 3 of 8
When listening to John’s heart you notice a heart murmur that was not noted on John’s earlier health history. Which structures may have been damaged by John’s myocardial infarction that elicited this new murmur? Superior vena cava Pulmonary artery Aorta Papillary muscles
Papillary Muscles
The papillary muscles are attached the atrioventricular (AV) valves and help keep the valves closed during ventricular systole. A myocardial infarction may damage the papillary muscles. If the papillary muscles can not function properly, the valve closure may be disrupted, enabling blood to flow through the valve during systole, resulting in turbulent flow and a heart murmur.
Question 4 of 8
The physician is closely monitoring John’s ECG because she is worried about a rhythm disturbance that may develop as a result of reentry circuits. Given John’s current presentation, which of the following is the most concerning?
First degree AV block
Ventricular tachycardia
Atrial fibrillation
A single premature ventricular contraction (PVC)
Ventricular tachycardia
Because of the location of John’s myocardial infarction, you are most concerned about a conduction disturbance in the ventricles. Ventricular tachycardia is the most worrisome of the conduction disorders listed as it can result in inadequate pumping of blood from the left ventricle. Atrial disorders or a single PVC do not normally result in significant decline in ventricular function at rest.
Question 5 of 8
Because of the damage to the left ventricle, the physician is concerned about poor ejection and stasis of blood in the ventricular chamber leading to further complications. Which of the following may be a primary concern? Atrial fibrillation Thromboembolism First degree AV block Collateral circulation development
Thromboembolism
When stasis of the blood occurs, the risk of clot development increases. In John’s case, a poorly performing left ventricle may increase the risk of a thromboembolism forming. This clot can then travel from the heart to other tissues, such as the lungs.
Question 6 of 8
The physician orders an echocardiogram to get a better sense of John’s heart function. There is a bulging left ventricular wall. Which of the following terms describe this development? Cardiac tamponade Papillary muscle rupture Ventricular aneurysm Pericarditis
Ventricular aneurysm
A ventricular aneurysm is a bulge in the ventricular wall that develops as a result of damage to the tissue. A primary concern of a ventricular aneurysm is that the bulge may rupture leading to a medical emergency. Surgical repair of a ruptured ventricular aneurysm is critical.
Question 7 of 8
John’s pulmonary function is also being closely monitored. Over time, John seems to have difficulty maintaining adequate arterial oxygen levels. When you auscultate John’s lungs you hear the presence of crackles. What complication do you suspect may be developing?
Pneumonia
Chronic obstructive pulmonary disease (COPD)
Heart murmur
Heart failure
Heart failure
As John’s left ventricle was damaged, it may not be able to adequately pump blood forward into circulation. The lack of forward ejection results in blood pooling in the left atrium and finally backing up into pulmonary circulation. As hydrostatic pressure in the pulmonary capillaries increases due to the fluid backup, fluid leaks from the capillaries, leading to pulmonary edema noted by the presence of crackles.
Question 8 of 8
John is eventually discharged from the hospital. However, John returns 10 days later complaining of chest pain and fever. He states the chest pain worsens when he takes a deep breath. On auscultation of John’s chest, a pericardial friction rub is present. What has John developed?
Beck’s triad
Dressler’s syndrome
Prinzmetal angina
Syndrome X
Dressler’s syndrome
Dressler’s syndrome may develop 2 to 3 weeks after a myocardial infarction. Dressler’s syndrome is an autoimmune process in which antibodies and an inflammatory response occur as a result of cardiac proteins being released during a myocardial infarction. The immune complexes deposit in the pericardium, causing pericarditis. Pericarditis may present with a pericardial friction rub heard on auscultation.
Question 1 of 5
Following a myocardial infarction, the sac surrounding the heart may become inflamed. Which structure may develop inflammation?
Pleural space
Thymus
Pleural membrane
Pericardium
Pericardium
Question 2 of 5
A block at the AV node is likely to appear as a(n) ___________________ on an ECG.
widened QRS complex
PVC
prolonged PR interval
inverted P wave
prolonged PR interval
Question 3 of 5
Rapid, irregular P waves are known as ____________.
AV block
atrial fibrillation
ventricular fibrillation
ventricular tachycardia
atrial fibrillation
Question 4 of 5
A single, widened QRS complex is referred to as a _______________.
bigeminy
PVC
ventricular tachycardia
couplet
PVC
Question 5 of 5
Which conduction abnormality is associated with an increased risk for clot formation?
PVC
AV block
AV fibrillation
Couplet
AV fibrillation
