Term
| Given a list of indications, choose those relative to performing an echocardiogram on fetal circulation |
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Definition
•Evaluation of the heart in the setting of retarded fetal growth or fetal distress.
•Extracardiac anomalies detected during fetal ultrasound.
•The presence of chromosomal abnormalities detected with amniocentesis.
•Assessment of fetal arrhythmias.
•Maternal exposure to teratogenic substances or a parental history of previous children with congenital lesions |
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Term
| Describe intracardiac echocardiography |
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Definition
| This technology involves a single-plane, high-frequency transducer on the tip of a steerable intravascular catheter, typically 9-13 French size. The catheter can be steered in both directions and can be retroflexed and anteflexed. There is a 64-element single-plane ultrasound transducer mounted at the tip that provides high-resolution, two-dimensional imaging as well as color flow imaging and Doppler spectral imaging |
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Term
| State where intracardiac echocardiography is applicable |
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Definition
| This technique is obviously applicable only in the cardiac catheterization laboratory and requires large bore intravascular access |
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Term
| State the uses of intracardiac echocardiography |
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Definition
| This technique has seen greatest use for monitoring complex interventional procedures such as percutaneous ASD closure, atrial septostomy, and pulmonary vein isolation for treatment of A-Fib |
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Term
| Define intravascular ultrasound |
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Definition
| Typically, these are ultraminiaturized ultrasound transducers mounted on modified intracoronary catheters. Most devices provide anatomic imaging and do not provide Doppler information. Intracoronary ultrasound is by definition performed in the CCL and in a majority of instances is performed by an invasive cardiologist rather than a dedicated echocardiographer. The technique provides high-resolution images of the proximal coronary arteries and can identify calcification and plaque and further characterize plaque |
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Term
| State the uses of intravascular ultrasound |
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Definition
| The technique was instrumental in determining the optimal methods for intracoronary stent deployment. It is usually most often used to define the true anatomic severity of “intermediate” coronary lesions noted on angiography or for highly precise evaluation of coronary arterial wall anatomy |
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Term
| State the use of Doppler flow wires |
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Definition
| Data from intracoronary Doppler flow wires can be used to assess the integrity of hyperemic reserve by determining flow characteristics under basal conditions and after vasodilation. It provides another method for defining the physiologic significance of a coronary stenosis |
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Term
| State the major advantage of digital echocardiography |
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Definition
| A major advantage of the digital environment is the ability to pull up and compare in a side-by-side format multiple studies. This allows a side-by-side display of equivalent images recorded at two different points in time for evaluation of serial changes and has particular relevance with respect to evaluating resolution of wall motion abnormalities after AMI, serial changes in valvular insufficiency, or serial changes in LV function |
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Term
| State the use of echocardiography in patients with known or suspected ischemic heart disease |
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Definition
| The use of echocardiography in patients with known or suspected ischemic heart disease is broad ranging and includes playing a role in diagnosis, detecting complications, and assessing prognosis |
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Term
| Describe normal left ventricular wall motion and the results of interruption of contraction |
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Definition
| Normal left ventricular wall motion consists of simultaneous wall thickening and endocardial excursion so that the cavity decreases in size in a relatively symmetric manner. Interruption of contraction, due to ischemia, infarction, or other process, results in regional abnormalities of wall motion |
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Term
| Identify the echocardiographic sequence of events that occur after coronary artery occlusion |
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Definition
| Immediately after coronary artery occlusion, abnormalities in diastolic function occur and can be detected with echocardiographic and Doppler techniques. The easiest and most commonly identified abnormality is abnormal mitral valve inflow, with reduction in E-wave velocity and an increase in A-wave velocity occurring within seconds of total coronary occlusion. Additionally, there may be a visibly abnormal relaxation pattern to the wall, mimicking a conduction abnormality. This is followed almost immediately by the loss of systolic wall thickening and decreased endocardial excursion in the region perfused by the obstructed coronary artery. If the coronary artery obstruction persists for a threshold period (typically defined as > 4hrs) myocardial necrosis ensues and a persistent wall motion abnormality will develop. |
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Term
| Define and discuss the impact myocardial tethering has on the estimating the extent of a wall motion abnormality |
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Definition
| Although the location of a wall motion abnormality is an accurate marker for the site of ischemia or infarction, the extent of the wall motion abnormality often overestimates the anatomic extent of ischemia or infarction. This is due in large part to tethering. Myocardial tethering refers to the impact that an abnormal segment has on a normal adjacent border segment. Tethering occurs both on a horizontal and vertical basis. Horizontal tethering occurs when there is akinesis or dyskinesis of a segment that then results in the reduction in endocardial excursion in the adjacent functionally normal boundary tissue. The effect of horizontal or lateral tethering is for the extent of a wall motion abnormality to overrepresent the anatomic circumferential extent of myocardial necrosis because the detected wall motion abnormality includes not only the infarcted tissue but also a variable percentage of the immediately adjacent boundary tissue. Generally, the wall motion abnormality will overestimate the anatomic extent of a myocardial infarction by approximately 15% due to this phenomenon. |
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Term
| Discuss how regional left ventricular wall motion and global ventricular function can be analyzed |
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Definition
| Regional left ventricular wall motion and global ventricular function can be analyzed and quantified using a number of schemes. These can be classified as purely qualitative, semiquantitative, and quantitative assessments. Although detailed quantitative schemes, which measure regional or global function as a percentage of anticipated normal, may be useful for serial studies and investigational protocols, they are not necessary for detection and localization of an ischemic event for clinical diagnosis. A compromise that allows semiquantitation and that can be employed easily is the generation of a wall motion score. |
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Term
| State why M-mode measurements provide only limited information on patients with coronary artery disease |
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Definition
| M-mode LV measurements provide only limited information on patients with coronary artery disease, not only because of the regional nature of the left ventricular function but also because the M-mode dimensions are not true minor axis measurements |
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Term
| 58. State which method has replaced M-mode echocardiography for evaluation of global and regional wall motion |
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Definition
| Two-dimensional imaging has replaced M-mode echocardiography for evaluation of global and regional wall motion. |
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Term
| State the most commonly used method for volume determination |
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Definition
| The most commonly used method for volume determination is the Simpson rule, or the rule of disks |
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Term
| Given a selection of standard wall motion scores match them to their corresponding descriptions Echocardiography |
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Definition
Normal- 1
Hypokinetic- 2
Akinetic- 3
Dyskinetic- 4
Aneurysm- 5 |
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Term
| Discuss the role echocardiography plays in establishing the diagnosis of acute myocardial infarction |
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Definition
| Urgent 2D echocardiography can play a crucial role in establishing the diagnosis of AMI and determining its location, extent, and prognosis. In the presence of chest pain with EKG changes, detection of a RWMA is direct evidence of myocardial ischemia, and the extent of the wall motion abnormality is directly related to the volume of myocardium in jeopardy. One should appreciate the independence of the wall motion abnormality from EKG changes because wall motion abnormalities will be seen in the absence of traditional Q-wave infarct. |
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Term
| List the role (impact) that transthoracic echocardiography has in patients presenting with chest pain syndromes |
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Definition
| In contemporary practice, resting TTE is rarely used as a stand alone technique in patients presenting with chest pain syndromes. Many aggressive centers have adopted an approach of early stress echocardiography in patients with normal resting wall motion who have presented with chest pain suggesting an acute coronary syndrome. |
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Term
| Given a list select the natural course of an acute myocardial infarction |
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Definition
| Without the successful restoration of flow, the natural course of acute myocardial infarction is for transmural necrosis to occur. In this instance, there will be no recovery of function in the infarct zone. The border zones that may have had compromised myocardial perfusion acutely and hence have abnormal wall motion may show recovery of function; however, the central transmural infarct zone will remain akinetic. Over approximately a 6 week period, myocardial necrosis is replaced by fibrosis and scar. Both pathologically and echocardiographically the wall becomes thinner and denser. More chronically, aneurysm formation and remodeling may occur than can have deleterious effects on ventricular performance |
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Term
| List four complications of acute myocardial infarction |
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Definition
| Pericardial effusion, Infarct expansion, Free-Wall rupture, Ventricular thrombus, RV infarction, Acute MR, Ventricular septal rupture |
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Term
| Discuss infarct expansion and identify its implications |
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Definition
| Infarct expansion represents acute thinning of the ventricular wall with aneurysmal dilation, occurring 24-72 hours after transmural myocardial infarction. It represents an acute remodeling phenomenon and carries significant prognostic implications. This complication is not seen in nontransmural infarction. It is more common after anteroapical myocardial infarction than posterior distribution infarction. The wall in the area of infarct expansion consists of necrotic myocardial tissue, which because it has expanded or been stretched over a larger endocardial surface area may only be 4-6 mm in thickness and have markedly reduced structural integrity. The thin necrotic wall has low tensile strength and is the precursor to most mechanical complications. This complication should be recognized because it is the precursor to mechanical complication such as free-wall rupture, ventricular septal rupture, and papillary muscle rupture. |
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Term
| 66. State the location that ventricular thrombus is most often associated with after an acute myocardial infarction |
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Definition
| It is virtually always associated with anteroapical myocardial infarction with relatively extensive areas of abnormal wall motion. It is infrequently reported in inferior MI. |
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Term
| State when right ventricular infarction occurs |
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Definition
| RV infarction occurs most commonly (>90%) in conjunction with inferior myocardial infarction. On rare occasions, patients are noted with LAD coronary artery distribution infarction and concurrent RV involvement. This is typically due to a variation of coronary anatomy in which RV branches arise from the LAD. The overwhelming majority of RV infarctions, however, will be seen in the presence of inferior myocardial infarction due to occlusion of the proximal RCA |
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Term
| Given a list of echocardiographic abnormalities, choose the ones relative to right ventricular infarction |
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Definition
| With RV infarction, dilation of the RV and tricuspid annulus is common. Secondary tricuspid regurgitation is often seen. In many instances, more subtle degrees of RV dysfunction will be present in which frank dilation and akinesis may not be noted. The elevation of right heart pressure may result in substantial amounts of R-L shunting through a PFO. Concurrent MR or VSD all increase the work of the RV acutely and the combination of RV involvement with either of these entities confers a substantially worse prognosis |
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Term
| State which echocardiographic technique is crucial for evaluation of possible papillary muscle rupture |
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Definition
| Color flow imaging is crucial for evaluation of possible papillary muscle rupture |
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Term
| State what type of myocardial necrosis leads to ventricular septal rupture |
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Definition
| As with other forms of mechanical disruption it is virtually always associated with transmural rather than nontransmural myocardial necrosis, and acute infarct expansion is the precursor |
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Term
| When evaluating patients for ventricular septal defects after a myocardial infarction state which standard echocardiographic views and techniques are most helpful |
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Definition
| When evaluating patients for VSD it is often necessary to use unconventional imaging planes. It is often most advantageous to first scan using CFI in an effort to identify the pathologic L-R flow rather than scanning looking for the anatomic defect |
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Term
| State the definition and description of an LV aneurysm and pseudoaneurysm |
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Definition
| LV pseudoaneurysm represents a contained rupture of the LV free wall. In rare instances, a pseudoaneurysm can actually occur within the ventricular septum rather than along the free wall. It is important to recognize a pseudoaneurysm because the likelihood of spontaneous rupture is high. Unlike a true aneurysm in which the wall consist of dense tensile strength, the wall of a pseudoaneurysm is composed of organizing thrombus and varying portions of the epicardium and parietal pericardium. Pathologically it is the sequela of myocardial rupture with hemorrhage into the pericardial space, which then becomes locally compressive. Local tamponade occurs, preventing further hemorrhage into the pericardium. Over time, the intrapericardial thrombus organizes, creating a wall to the pseudoaneurysm, however, with poor structural integrity. As such it is at risk of spontaneous rupture, which is generally a fatal event |
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Term
| Discuss differentiating between true and pseudoaneurysms |
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Definition
| Pseudoaneurysms can be separated from true aneurysms by several characteristics. Separation of true from pseudoaneurysms in the proximal posterior wall is often problematic, however. Traditionally it is thought that if the size of the opening to the LV cavity is less than the maximal dimension of the aneurysm, the defect is more likely to be a pseudoaneurysm. Because the pseudoaneurysm is composed of both a free aneurysmal cavity and the organizing hematoma, its true size is often underrepresented on echocardiography because the organized hematoma has a soft-tissue density similar to that of many surrounding structures. Pseudoaneurysm at the base of the heart (most commonly after an acute MI) may be difficult to separate from a true aneurysm. In this location, they may have a wider mouth than is traditionally thought and can be difficult to distinguish from a true aneurysm. |
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Term
| List the role echocardiography plays in detecting Kawasaki disease |
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Definition
| Because this is a childhood disease, in which coronary visualization is often less problematic, screening the coronary arteries with TTE provides a reliable tool for establishing or excluding the diagnosis of the disease. High frequency scanning can frequently demonstrate thrombus lining the wall of an aneurysm. 2D echo is used as a tool for follow-up of these aneurysms because their size and appearance may change over time |
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Term
| List the single factor that led to the rapid development of stress echocardiography as a clinical tool and why |
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Definition
| Improvement in image quality and the development of digital acquisition contributed to greater accuracy and increased the practicality of using stress echocardiography in clinical situations. Most important, the digitization of echocardiographic images reduced the problem of respiratory interference by permitting selection of cardiac cycles that were devoid of lung interference and the creation of cine loops that permitted side-by-side analysis of rest and stress images. This allowed more accurate interpretation of wall motion, largely by permitting relatively subtle changes in stress-induced wall motion to be detected. Digital technology also shortened the acquisition time for postexercise imaging and facilitated display, storage, and transmission of echocardiographic data. |
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Term
| Define stunned myocardium |
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Definition
| Stunned myocardium is the term applied when functional abnormalities persist after transient ischemia for a longer period. Although a reversible process, stunning may last days or even weeks if the ischemia is severe and prolonged |
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Term
| Discuss the utility of echocardiography in conjunction with stress testing |
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Definition
| The utility of echocardiography in conjunction with stress testing is contingent upon the ability to record wall motion and LV function at baseline and then to detect changes after the induction of stress, either exercise or pharmacologic |
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Term
| Discuss the effects of regional wall motion abnormalities present at baseline or during stress |
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Definition
| At baseline, the presence of a RWMA generally implies the presence of previous myocardial damage, in most cases due to MI. Less often, cardiomyopathy and stunned or hibernating myocardium cause resting WMA’s. Regional deterioration of LV function during stress is a specific marker of ischemia. Although exercise induced wall motion abnormalities may occasionally occur in normal individuals after prolonged, intense exercise, this type of response during stress testing is usually the result of significant coronary disease. A global decrease in LV function in response to stress, however, may be due to other causes, such as hypertension or cardiomyopathy. Therefore, by comparing RWM at baseline and during stress, the presence of inducible ischemia can be detected and localized |
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Term
| State the most popular form of pharmacologic stress echocardiography |
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Definition
| The most common pharmacologic agent used in conjunction with echocardiography is dobutamine |
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Term
| State 4 stressors less commonly used in stress echocardiography testing |
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Definition
| Less commonly used stressors include isometric exercise such as handgrip, vasodilators such as dipyridamole or adenosine, and pacing, usually through a transesophageal approach |
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Term
| State the most common form of stress testing in the United States and why |
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Definition
| Treadmill exercise is the most common form of stress testing in the United States. It provides a plethora of useful clinical information that has both diagnostic and prognostic value. These include exercise capacity, blood pressure response, and arrhythmias. It is safe and well tolerated and can be applied to a large percentage of the patients referred for stress testing |
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Term
| Name two categories of contrast echocardiographic techniques that can be applied to stress testing |
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Definition
| The application of contrast echocardiographic techniques to stress testing falls into two distinct categories: LV opacification for border enhancement and myocardial perfusion imaging |
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Term
| Describe the concept and benefits of using an intravenous contrast agent to enhance left ventricular border detection |
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Definition
| The concept of using an IV contrast agent to improve LV border detection is predicated on its ability to cross the pulmonary circuit and provide sufficient left-sided chamber opacification. As such, this application is not limited to stress echocardiography but has utility whenever image quality adversely affects wall motion assessment. By improving endocardial border detection, the accuracy with which systolic function and wall motion analysis can be ascertained is increased |
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Term
| Discuss the application of contrast agents to detect stress induced myocardial perfusion abnormalities |
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Definition
| The application of contrast agents to detect stress-induced myocardial perfusion abnormalities is an area of intense clinical investigation. In theory, a perfusion defect must precede the development of a wall motion abnormality so a method to assess myocardial perfusion should increase the sensitivity of the test to detect ischemia. After IV injection the distribution of the contrast agent parallels blood flow and can be visualized as it traverses the microvasculature of the tissue, generating a time-intensity curve. Thus, perfusion can be assessed as a relative change (rest vs. stress), a regional difference (lateral wall vs. septum) or more quantitatively based on changes in the rate of flow or blood volume. An echocardiographic test that combines wall motion assessment with the simultaneous ability to evaluate perfusion changes in response to stress would have considerable utility |
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