Determination of interobserver variability for identifying inducible left ventricular wall motion abnormalities during dobutamine stress magnetic resonance imaging.

AIMS: To determine the interobserver variability for identifying inducible left ventricular (LV) wall motion abnormalities during high-dose dobutamine/atropine stress cardiovascular magnetic resonance (DSMR). METHODS AND RESULTS: Four readers from various institutions were supplied with the image data from 150 consecutive DSMR examinations and asked to grade wall motion and image quality throughout graded doses of dobutamine infusion administered to achieve 85% of the maximum age-predicted heart rate. Inducible ischaemia was identified if more than one segment demonstrated a new or worsening LV wall motion abnormality, and significant stenosis was defined as > or =50% luminal diameter reduction by quantitative contrast coronary angiography. Seventy-seven patients (51%) had luminal narrowings > or =50%. Diagnostic performance (sensitivity, specificity, diagnostic accuracy) of all readers was 78.2, 87.0 and 82.5%. Disagreement between two readers occurred in every seventh examination. Agreement on the presence or absence of inducible wall motion abnormalities was moderate (mean kappa value 0.59, range 0.52-0.76). Diagnostic performance and disagreement were independent of the presence of luminal narrowings > or =50% or the number of diseased coronary vessels. Image quality was regarded excellent in 89.3% of standard views. CONCLUSION: In the setting of multiple observers from different institutions performing a diagnostic reading of DSMR examinations carried out at a single centre, the interobserver variability was low for identifying inducible LV wall motion abnormalities indicative of coronary arterial luminal narrowings > or =50%.     

Prediction of coronary artery disease by left ventricular regional wall motion abnormalities in patients with stenosis of the aortic valve.

To identify predictive factors for coronary artery disease in patients with stenosis of the aortic valve the clinical histories, haemodynamic measurements, biplane contrast left ventriculograms, and coronary angiograms of 83 consecutively catheterised patients with valvar aortic stenosis were examined retrospectively. The mean (SD) age was 66.4 (9.1) years and 78% were men. Fifty five patients had significant coronary artery disease (greater than or equal to 50% diameter narrowing). Forty five (82%) of 55 patients with and 23 (82%) of 28 patients without coronary disease had angina. Heart failure occurred in a third of the patients; these patients were on average older, were more likely to be female, and had lower ejection fractions and cardiac outputs than patients in whom failure did not occur. Calculated valve area, transvalvar gradient, and left ventricular end diastolic pressure did not discriminate between patients with and without coronary disease. Syncope was less common than angina and heart failure and was associated with significantly lower valve areas and higher gradients than those found in patients without syncope. Left ventricular regional wall motion abnormalities were equally common in the groups with and without angina and predicted coronary artery disease with 94% accuracy. The absence of regional wall motion abnormality was an insensitive marker of normal coronary arteries as 45% of such patients had coronary disease. Five of the 83 patients had significant coronary disease without angina or regional wall motion abnormality. In patients with aortic stenosis angina did not predict the presence of coronary artery disease; therefore, it is advisable to have the results of coronary angiography before aortic valve replacement in a population such as this. Two of the patients with heart failure and severe aortic stenosis had regional wall motion abnormality with normal coronary arteries. Thus in some patients left ventricular failure produced by increased afterload may itself be a cause of left ventricular regional wall motion abnormality.     

Prediction of coronary artery disease by left ventricular regional wall motion abnormalities in patients with stenosis of the aortic valve

To identify predictive factors for coronary artery disease in patients with stenosis of the aortic valve the clinical histories, haemodynamic measurements, biplane contrast left ventriculograms, and coronary angiograms of 83 consecutively catheterised patients with valvar aortic stenosis were examined retrospectively. The mean (SD) age was 66.4 (9.1) years and 78% were men. Fifty five patients had significant coronary artery disease (greater than or equal to 50% diameter narrowing). Forty five (82%) of 55 patients with and 23 (82%) of 28 patients without coronary disease had angina. Heart failure occurred in a third of the patients; these patients were on average older, were more likely to be female, and had lower ejection fractions and cardiac outputs than patients in whom failure did not occur. Calculated valve area, transvalvar gradient, and left ventricular end diastolic pressure did not discriminate between patients with and without coronary disease. Syncope was less common than angina and heart failure and was associated with significantly lower valve areas and higher gradients than those found in patients without syncope. Left ventricular regional wall motion abnormalities were equally common in the groups with and without angina and predicted coronary artery disease with 94% accuracy. The absence of regional wall motion abnormality was an insensitive marker of normal coronary arteries as 45% of such patients had coronary disease. Five of the 83 patients had significant coronary disease without angina or regional wall motion abnormality. In patients with aortic stenosis angina did not predict the presence of coronary artery disease; therefore, it is advisable to have the results of coronary angiography before aortic valve replacement in a population such as this. Two of the patients with heart failure and severe aortic stenosis had regional wall motion abnormality with normal coronary arteries. Thus in some patients left ventricular failure produced by increased afterload may itself be a cause of left ventricular regional wall motion abnormality.     

Comparison of exercise radionuclide angiography with thallium SPECT imaging for detection of significant narrowing of the left circumflex coronary artery.

Although quantitation of exercise thallium tomograms has enhanced the noninvasive diagnosis and localization of coronary artery disease, the detection of stenosis of the left circumflex coronary artery remains suboptimal. Because posterolateral regional wall motion during exercise is well assessed by radionuclide angiography, this study determined whether regional dysfunction of the posterolateral wall during exercise radionuclide angiography is more sensitive in identifying left circumflex disease than thallium perfusion abnormalities assessed by single-photon emission computed tomography (SPECT). One hundred ten consecutive patients with CAD were studied, of whom 70 had a significant stenosis of the left circumflex coronary artery or a major obtuse marginal branch. Both regional function and segmental thallium activity of the posterolateral wall were assessed using visual and quantitative analysis. Left ventricular regional function was assessed objectively by dividing the left ventricular region of interest into 20 sectors; the 8 sectors corresponding to the posterolateral free wall were used to assess function in the left circumflex artery distribution. Similarly, using circumferential profile analysis of short-axis thallium tomograms, left ventricular myocardial activity was subdivided into 64 sectors; the 16 sectors corresponding to the posterolateral region were used to assess thallium perfusion abnormalities in the left circumflex artery territory. Qualitative posterolateral wall motion analysis detected 76% of patients with left circumflex coronary artery stenosis, with a specificity of 83%, compared with only 44% by qualitative thallium tomography (p less than 0.001) and a specificity of 92%. Whereas quantitation of thallium activity increased the sensitivity for detecting left circumflex coronary artery stenosis to 80% with a specificity of 55%, it did not achieve statistical significance when compared with qualitative wall motion analysis.(ABSTRACT TRUNCATED AT 250 WORDS)     

The echo-dobutamine test for the diagnosis of myocardial ischemia. Study on 20 patients with normal kinetics at rest

We have assessed the value of dobutamine stress echocardiography for the diagnosis of myocardial ischemia in 20 consecutive patients referred for chest pain, without a previous myocardial infarction and with a normal left ventricular wall motion at rest. The test was considered positive when wall motion abnormalities appeared during dobutamine infusion (from 5 to a maximum of 40 micrograms/Kg/min). The results were compared to the % diameter stenosis (%DS) quantitatively measured on coronary arteriography. "Significant" coronary artery disease was defined as greater than or equal to 50% DS. No significant side effects occurred in any patients during the test. Transient wall motion abnormalities were detected in 8 of the 12 patients with significant coronary artery disease (sensitivity = 66%) and in 1 of the 8 patients without significant coronary artery disease (specificity = 88%). All the patients with false-negative dobutamine stress echocardiography had distal stenosis or stenosis in a collateral vessel; moreover, all the patients with true-positive dobutamine stress echocardiography had proximal (7 patients) or middle (1 patient) stenosis. The results of this study show that dobutamine stress echocardiography is a safe and feasible test for the noninvasive diagnosis of myocardial ischemia.     

Quantitative assessment of transient left ventricular asynergy in coronary artery disease

The purpose of this study was to determine the diagnostic value of quantitative two-dimensional echocardiography during transesophageal atrial pacing in assessing the presence and severity of coronary artery disease. Apical four- and two-chamber views were registered at rest and at different pacing rates. Computerized quantitative evaluation of left ventricle wall motion was performed. On the basis of left ventricle wall motion analysis data of 22 individuals with no coronary pathology, as assessed by angiography and with negative exercise ECG and transesophageal atrial pacing ECG test, nomograms for assessment of wall motion abnormalities and for calculation of asynergy area as a measure of wall motion abnormality extent were obtained. The method revealed new transient wall motion abnormalities during pacing or exacerbation of old ones present at rest in 83 of the 89 patients with angiographically proven coronary artery stenosis greater than or equal to 70% and in 3 of the 32 controls with no changes in their coronary angiograms. Thus, it showed high sensitivity (93%), specificity (91%), predictive value of positive result (96%), predictive value of negative result (83%), and efficiency of the test (93%). These values appeared to be higher than those calculated for transesophageal atrial pacing ECG, recorded simultaneously with echocardiographic images (81, 87, 95, 62, and 83%, respectively) and for exercise ECG test which was performed in 66 coronary patients and in 29 controls (68, 86, 92, 54, and 74%, respectively). The extent of pacing-induced left ventricular regional wall motion abnormalities appeared to be directly correlated to the extent of coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)     

Left ventricular dysfunction in patients with angina pectoris and normal coronary angiograms

Left ventricular function was assessed in 201 patients who presented with angina pectoris and who were subsequently found to have completely normal coronary angiograms. Left ventricular angiograms from 187 patients were suitable for analysis of systolic regional wall motion; 121 were found to be normal and 66 had a total of 115 hypokinetic segments. Patients with hypokinesia had a significantly higher left ventricular end systolic volume and a significantly lower left ventricular ejection fraction and exercise capacity than those in whom regional wall motion was normal. Thirty one per cent of patients with normal wall motion and 30% of those with hypokinesia had a resting left ventricular end diastolic pressure greater than 15 mm Hg. There were significantly more smokers in the group with hypokinetic segments. Thus of patients with angina and normal coronary angiograms, 25% had evidence of left ventricular systolic dysfunction, 20% had evidence of diastolic dysfunction, and 11% had evidence of both systolic and diastolic dysfunction. The results suggest that smoking may be associated with left ventricular regional wall motion abnormalities.     

Left ventricular dysfunction in patients with angina pectoris and normal coronary angiograms.

Left ventricular function was assessed in 201 patients who presented with angina pectoris and who were subsequently found to have completely normal coronary angiograms. Left ventricular angiograms from 187 patients were suitable for analysis of systolic regional wall motion; 121 were found to be normal and 66 had a total of 115 hypokinetic segments. Patients with hypokinesia had a significantly higher left ventricular end systolic volume and a significantly lower left ventricular ejection fraction and exercise capacity than those in whom regional wall motion was normal. Thirty one per cent of patients with normal wall motion and 30% of those with hypokinesia had a resting left ventricular end diastolic pressure greater than 15 mm Hg. There were significantly more smokers in the group with hypokinetic segments. Thus of patients with angina and normal coronary angiograms, 25% had evidence of left ventricular systolic dysfunction, 20% had evidence of diastolic dysfunction, and 11% had evidence of both systolic and diastolic dysfunction. The results suggest that smoking may be associated with left ventricular regional wall motion abnormalities.     

Serial analysis of regional left ventricular wall motion by two-dimensional echocardiography in patients with coronary artery enlargement after Kawasaki disease.

OBJECTIVES. This study was designed to assess the temporal relation between early coronary artery abnormalities and left ventricular function in Kawasaki disease. BACKGROUND. Although late segmental wall motion abnormalities may be seen in patients with Kawasaki disease who have coronary artery stenosis, the impact of early coronary artery abnormalities is unclear. METHODS. Regional left ventricular wall motion was assessed by two-dimensional echocardiography in 18 patients with Kawasaki disease and echocardiographic evidence of coronary artery enlargement at 3 weeks and 3 months and at either 6 or 12 months after the onset of fever. Four patients had a persistent left coronary artery aneurysm, four had regression of their aneurysm, two had persistent left coronary artery ectasia and eight had regression of ectasia. Left ventricular wall motion was assessed by measuring regional area change in parasternal and apical views. After planimetry of an end-systolic and an end-diastolic frame, the ventricle was divided into eight equal segments and the percent area change was calculated. A floating system correcting for translation and rotation was applied. The measurements in the patient group were compared with values previously obtained in 55 normal age-matched infants and children. RESULTS. A transient regional wall motion abnormality 3 and 6 months after the onset of fever was discovered in the inferolateral wall of one patient with a persistent left coronary artery aneurysm. One patient with regression of coronary artery ectasia had a persistent wall motion abnormality in the anterolateral left ventricular wall. There was no correlation between the extent of coronary artery enlargement and the presence or absence of wall motion abnormalities. CONCLUSIONS. These early changes are most likely secondary to associated myocarditis rather than coronary artery abnormalities.     

Left ventricular regional dysfunction induced by intracoronary papaverine in patients with isolated stenosis of the left anterior descending coronary artery.

Intracoronary papaverine was administered to eight subjects with normal coronary arteries and to nine patients with single-vessel disease of the left anterior descending coronary artery. All patients had normal left ventricular function at baseline. After papaverine, global and regional ventricular function were unchanged in the normal group. In patients with left anterior descending coronary artery stenosis, intracoronary papaverine resulted in significant wall motion abnormalities and decrease of ejection fraction (from 65 +/- 6% to 54 +/- 9%, p less than 0.01). A full spectrum of responses was observed, however, in these patients, some having almost no change of regional wall motion while others had large anterior dyskinesis. No relationship was found between the severity of the stenosis and the amount of regional dysfunction induced by intracoronary papaverine. These data demonstrate the lack of relationship between the angiographic severity of a stenosis and its impact on left ventricular segmental contraction. This suggests that techniques aimed at producing wall motion abnormalities by means of coronary anterior vasodilation may not be recommended as first-line strategy for the detection of patients with coronary artery disease.     

Localization of a Coronary Stenosis, Left Ventricular Function, and Pain Perception During Myocardial Ischemia in Patients with One-Vessel Disease

Silent Myocardial Ischemia and Endogenous Pain Modulation. A total of 97 patients with asymptomatic and 69 patients with symptomatic myocardial ischemia and one-vessel disease were compared with respect to the location of coronary stenosis and left ventricular wall motion abnormalities. All symptomatic and asymptomatic patients exhibited reproducible objective signs of myocardial ischemia in exercise tests, ischemia being always silent in the asymptomatic group. Right coronary artery stenosis (and left circumflex artery stenosis) was more frequently observed in asymptomatic patients, left artery descending stenosis more often in symptomatic patients. Left ventricular wall movement abnormalities with posterobasal or diaphragmatic localization were significantly more often associated with the absence of angina pectoris pain. The present results could contribute to the understanding of the mechanisms underlying the absence of pain in silent myocardial ischemia. A possible explanation for these results would be that stimulation of inhibitory vagal afferents, which are preferentially distributed in the inferior ventricle wall, may play a role of the suppression of pain perception in myocardial ischemia.     

Left main coronary artery disease: radionuclide angiographic function versus anatomic correlates with visual and quantitative angiographic methods

The results of exercise radionuclide angiography in 29 patients with significant left main coronary artery stenosis were examined to correlate functional left ventricular performance with anatomic severity of left main coronary artery stenosis. Change in ejection fraction, regional wall motion, and peak ejection fraction were widely variable; none of these parameters correlated with severity of left main stenosis as assessed by visual or quantitative angiographic methods. Twenty-five patients (86%) had two or more of the following indicators of ischemia with exercise: chest pain, significant ST-segment depression, systolic hypotension, definite decrease in ejection fraction, or definite decline in regional wall motion. However, four patients (14%) had only mild abnormalities in ejection fraction and regional wall motion, although they did have hemodynamic and electrocardiographic evidence of severe ischemia. Exercise radionuclide angiography yields heterogeneous results in patients with significant left main coronary artery stenosis. Anatomically severe left main coronary artery stenosis is not always associated with mechanical evidence of severe ischemia.     

The influence of bias on the subjective interpretation of cardiac angiograms

Subjective interpretation of angiographic left ventricular regional wall motion is routinely performed with knowledge of the location and extent of coronary artery stenosis. We studied 100 patients with coronary artery disease in order to determine the accuracy of such wall motion assessment relative to a more objective standard based upon computer-assisted left ventricular (LV) ejection fraction and end-systolic fractional shortening referenced to the end-diastolic area centroid. Only 379 of 700 (54%) region-by-region comparisons of wall motion were in precise agreement. Computer-assisted wall motion analysis correlated significantly better with ejection fraction than did subjective analysis (r = 0.82 vs r = 0.61, p less than 0.002). In 56 patients, in whom major discordance was noted, subjective assessment of wall motion correlated significantly better with the presence of coronary artery stenosis (p less than 0.05), but objective assessment correlated significantly better with ejection fraction in these same patients (p less than 0.02). These data suggest that the accuracy of subjective assessment of regional wall motion, relative to global ejection fraction, can be adversely biased by knowledge of the patient's coronary anatomy. Because of the inherently reproducible nature of the algorithmic process, and in light of the better correlation with global function, computer-assisted analysis of regional wall motion might be preferable to conventional subjective assessment.     

Coronary microvascular abnormality in the reversible systolic dysfunction observed after noncardiac disease

Acute reversible left ventricular wall motion abnormalities mimicking myocardial stunning have been reported with noncardiac disease and their coronary angiograms did not demonstrate organic stenosis or vasospasm in the epicardial coronary arteries. Thus, this mechanism has not yet been fully clarified. Two patients are reported as demonstrating acute reversible wall motion abnormalities after noncardiac disease. The electrocardiographic and echocardiographic findings mimicked myocardial stunning and confirmed the previous reports. The coronary angiograms did not show any corresponding coronary stenosis or vasospasm, but did show a reduced coronary flow reserve. Cardiac metaiodobenzylguanidine scintigraphy demonstrated regional defects involving the apex, a decreased heart/mediastinum ratio and an enhanced washout rate, which partially returned to normal after 3 months. Microvascular dysfunction and sympathetic nervous abnormalities might be responsible for the reversible contractile impairment.     

Prediction of the extent of coronary artery disease with the evaluation of left ventricular wall motion abnormalities during atrial pacing. A cross-sectional echocardiographic study

In patients with coronary artery disease, left ventricular performance during stress is affected by the degree of coronary stenosis. In order to verify whether there exists a relationship between the extent of wall motion abnormalities detectable during atrial pacing and the degree of coronary obstruction, 76 patients, without previous myocardial infarction, were studied. Each patient underwent cross-sectional echocardiography during transesophageal atrial pacing and exercise electrocardiography before coronary angiography. Of the 76 patients, 46 had significant coronary artery disease (stenosis ⩾ 75% of at least one major coronary vessel), while 30 had normal coronaries or a stenosis of less than 75%. Eighteen patients had single-, 14 had two-and 14 had three-vessel disease. For each patient a coronary score was obtained: the score used took into consideration the site, number and severity of the stenosis. This score was then correlated with the wall motion score, obtained from the analysis of 9 segments of the left ventricle. A weak correlation was obtained between wall motion score at rest and coronary score (r = −0.42), while the correlation between coronary score and the difference between wall motion score at rest and during transesophageal atrial pacing was slightly better (r = 0.53); this correlation further improved if wall motion score during pacing was considered (r = −0.63). If the patients with discordant diagnostic tests (echocardiography during transesophageal atrial pacing and exercise electrocardiography) were excluded, the correlation coefficient between coronary score and wall motion score during pacing increased even more (r = −0.77).In conclusion: (1) analysis of wall motion of the left ventricle during atrial pacing is useful for the non-invasive evaluation of the severity of coronary disease; (2) cross-sectional echocardiography during atrial pacing, apart from being a useful diagnostic tool, is also a help in judging the degree of severity of coronary artery disease.     

Effect of exercise on left and right ventricular ejection fraction and wall motion.

OBJECTIVE: We evaluated the diagnostic value of response of left and right ventricular ejection fraction and wall motion to exercise using electron beam computed tomography. METHODS AND RESULTS: We attempted to determine the value of exercise electron beam computed tomography for detecting coronary artery disease, including evaluation of the right ventricular ejection fraction and wall motion abnormalities. A study of 35 patients undergoing electron beam tomography exercise cine studies and coronary artery angiography for the evaluation of chest pain was performed. Of the 18 patients with significant coronary disease (> or = 50% luminal diameter stenosis in at least one coronary artery), 17 (94%) had failure to increase global left ventricular ejection fraction with exercise. Fourteen of 18 (78%) developed a wall motion abnormality during peak exercise, and eight (44%) developed a regional right ventricular wall motion abnormality during peak exercise. Of the 17 patients without obstructive disease, 14 (82%) had a increase in ejection fraction > or = 5% and none had an abnormal response in left ventricular wall motion during peak exercise (specificity = 100%). The change in right ventricular ejection fraction with exercise was not a significant predictor of obstructive coronary disease in this study (P=NS). Using different criteria during stress to predict coronary disease, the accuracy was 89% (31/35) using an increase of <5% in ejection fraction, 89% (31/35) using the development of a new or worsened wall motion abnormality, and 91% (32/35) using both left ventricular criteria. CONCLUSION: Our study suggests that exercise electron beam computed tomography appears to be a useful tool for the detection of coronary disease. A increase of <5% in ejection fraction and abnormal left ventricular response to exercise were important predictors, while the exercise induced changes of right ventricular ejection fraction was not a significant predictor of obstructive disease. Both left and right ventricular wall motion abnormalities are useful and important parameters in identifying patients with obstructive disease from those with normal coronary arteries.     

Ischemic heart disease and regional left ventricular wall motion: a study comparing radial, centerline and a video intensity based slope technique

Left ventricular regional wall motion in ischemic heart disease was evaluated and compared using three different methods based on radiographic ventriculograms. Radial method uses an internal reference system, and centerline method employs an external reference system, both methods are based on two frame analysis. The last method, an automated video intensity technique, analyzes on a frame by frame basis utilizing an external reference system. A total of 42 patients were included in the study, of these 12 had a history of myocardial infarction. Significant coronary artery stenosis was defined as 50% measured diameter reduction. Right coronary artery (29/42) was most commonly involved. Single vessel disease was present in 18 patients, two vessel disease in 15 and three vessel disease in eight patients. The radial method detected abnormal wall motion in 16/42 patients, centerline method yielded a detection accuracy of 22/42 and with the new technique, asynchrony was noted in 39/42 patients. All three methods detected regional wall motion abnormalities with a higher sensitivity in patients with prior myocardial infarction. The centerline method had highest sensitivity for the right coronary artery bed (55%). The radial method (45%) and the video intensity based technique (95%) had the highest sensitivity for regions supplied by the left anterior descending artery.     

Anterior left ventricular wall echoes in coronary artery disease. Linear scanning with a single element transducer

The feasibility and usefulness of obtaining anterior left ventricular wall echoes were studied using a linear cardiac scan with a single element tranducer and M mode recordings. One hundred four patients were examined: 50 with acute myocardial infarction and 54 who underwent left ventricular angiography and coronary cineangiography for evaluation of chest pain. Of the 54 patients with cardiac catheterization studies, 11 had no evidence of cardiac disease, 42 had 50 percent or greater obstruction in one or more of the three major coronary arteries and one had aortic insufficiency. Anterior left ventricular wall echo motion toward the transducer or absence of motion during ejection was called abnormal, and motion away from the transducer during ejection was interpreted as normal. Abnormal motion was seen in four of four patients with an isolated lesion of the anterior descending coronary artery, in one of three with an isolated lesion of the right coronary artery and in neither of two with an isolated lesion of the left circumflex artery. Of the 20 patients with obstructive coronary artery disease by arteriography and abnormal left ventricular wall echo motion, 18 had obstruction of the left anterior descending artery with or without other disease. Correlation of the anterior left ventricular echograms with the left ventricular angiograms was poor, with agreement in only 66 percent (33 of 50) of cases. Twenty-five of 26 patients with acute infarction and abnormal anterior left ventricular wall echo motion had electrocardiographic changes indicative of anterior or lateral wall infarction, or both. Twenty-five of 34 patients with electrocardiographic changes indicative of anterior wall infarction had an abnormal anterior wall motion echo. This study shows that obtaining the anterior left ventricular wall echo is feasible and useful in patients with coronary artery disease since abnormal anterior left ventricular wall motion is closely associated with anterior wall ischemia or infarction in these patients.     

Stunned left ventricular myocardium after exercise treadmill testing in coronary artery disease

Myocardial stunning (postischemic ventricular dysfunction) occurs in dogs after coronary stenosis following treadmill exercise. Less data are available in humans regarding development of stunned myocardium after exercise. Regional wall motion changes were evaluated in 22 patients with known coronary artery disease using 2-dimensional echocardiography and exercise treadmill testing. Wall motion was scored as 1 = normal, 2 = hypokinetic, 3 = akinetic, 4 = dyskinetic. At least 1 left ventricular segment with normal resting function developed an increase in wall motion score at 15 or 30 minutes compared with values at rest. The wall motion score in the midportion of the ventricular septum increased from 1.0 at rest to 1.6 (p less than 0.004) at 30 minutes after exercise; the basal inferior wall score worsened from 1.0 at rest to 1.9 (p less than 0.01) at 30 minutes after exercise. Coronary angiographic data in these patients revealed that left anterior descending narrowing correlated best with left ventricular septal wall motion abnormalities, whereas right coronary artery and circumflex narrowing best correlated with inferior and posterior wall motion abnormalities. Eight normal adult volunteers with no history of myocardial ischemia also underwent 2-dimensional echocardiography and exercise testing. No wall motion abnormalities were observed at any time after exercise. The present study suggests that in patients with coronary artery disease, exercise treadmill testing may induce regional wall motion abnormalities of the left ventricle that persist greater than or equal to 30 minutes after exercise, an observation consistent with the phenomenon of stunned myocardium.     

Coronary artery thrombosis in patients with unstable angina.

This report describes the clinical course, coronary artery anatomy, and ventricular function of 16 patients in whom coronary artery thrombosis was detected at the time of cardiac catheterisation. All patients had an unstable clinical course in which accelerated angina occurred a mean of four weeks (range four days to 12 weeks) before catheterisation, and four patients had recent subendocardial myocardial infarction. In all patients severe coronary artery disease was documented at catheterisation. Fifteen patients had segmental wall motion abnormalities involving the left ventricular wall that was supplied by the coronary artery in which there was thrombus. Three patterns of coronary artery thrombus were noted: (1) Thrombus proximal to high-grade coronary artery stenosis; (2) thrombus distal to high-grade coronary artery stenosis; and (3) thrombus in segments of the arterial tree in which there was no high-grade coronary artery stenosis. Though the precise cause of the coronary artery thrombosis in our patients is unknown, it may have been a result of stasis, a ruptured atherosclerotic plaque, or coronary spasm. The common clinical course with unstable angina of acute onset suggests the possibility that the thrombus may have been responsible for the abrupt change in clinical condition or may have been a contributing factor in the patients' course.