Acute myocardial gray level intensity changes detected by transesophageal echocardiography during intraoperative ischemia.
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Densitometry↗
Biomedical subjects
E Picano
Publications and source records attributed to E Picano.
Exercise thallium scintigraphy versus high-dose dipyridamole echocardiography testing for detection of asymptomatic restenosis in patients with positive exercise tests after coronary angioplasty.
The usefulness of high-dose (< or = 0.84 mg/kg over 10 minutes) dipyridamole echocardiography testing was compared with that of exercise thallium-201 scintigraphy in detecting restenosis (> 70% lumen reduction) in 50 asymptomatic patients with ST-segment depression during maximal exercise testing 3 months after successful coronary angioplasty. Dipyridamole echocardiography testing and exercise thallium scintigraphy showed a similar sensitivity (75 vs 83%; p = NS) and specificity (90 vs 84%; p = NS) for the detection of restenoses, which occurred in 12 patients. It is concluded that dipyridamole echocardiography testing is as accurate as exercise thallium testing for the noninvasive detection of severe restenosis in patients with exercise-induced asymptomatic ST-segment depression after successful angioplasty. Furthermore, the site, extent and severity of the thallium perfusion defects during exercise are correlated to those of the dyssynergy during dipyridamole echocardiography.
Angioplasty, Balloon, Coronary↗
Value of rest thallium-201/technetium-99m sestamibi scans and dobutamine echocardiography for detecting myocardial viability.
The relation between radioisotopic and echocardiographic markers of myocardial viability and postrevascularization recovery of function is still to be defined. To this purpose, 14 patients (11 men, 3 women, aged 35 to 64 years, mean 54 +/- 7) with ventricular dysfunction were studied by a multiparametric approach. Each patient underwent, on separate days, rest thallium-201 and technetium-99m sestamibi scintigraphy, dobutamine echocardiography and coronary angiography. Coronary angiography was analyzed by a quantitative approach. Thallium uptake at rest was quantified from planar early (10-minute) and delayed (16-hour) thallium-201 images and expressed as a percentage of maximal activity in each projection using a 13-segment model. Sestamibi uptake was expressed in the same way. Dobutamine (up to 10 micrograms/kg/min) echocardiography was analyzed using a score index ranging from 1 (normokinesia) to 4 (dyskinesia) and a similar segmental model. Before revascularization 50 segments were grouped as normal (coronary stenosis < 50% and normal function, group 1); of the remaining 132 segments with > 50% coronary stenosis, 57 had normal wall motion (group 2) and 75 showed regional dyssynergies (group 3). Early and delayed thallium-201 regional percent activities did not differ in group 1 and in group 2 but were significantly less in group 3 segments. Sestamibi percent activity was more in group 1 and significantly reduced both in group 2 and 3 segments. Segments with improved wall motion after dobutamine had more early, delayed thallium-201 and sestamibi percent activities than unresponsive segments. Postrevascularization echocardiography was performed in all patients. Delayed thallium-201 scans and dobutamine echocardiography showed good sensitivity and specificity in detecting viable myocardium. (ABSTRACT TRUNCATED AT 250 WORDS)
Coronary Angiography↗
Prognostic value of dipyridamole echocardiography early after uncomplicated myocardial infarction: a large-scale, multicenter trial. The EPIC Study Group.
PURPOSE: To determine the prognostic capability of the dipyridamole echocardiography test (DET) early after an acute myocardial infarction. PATIENTS AND METHODS: On the basis of 11 different echocardiographic laboratories, all with established experience in stress echocardiography and fulfilling quality-control requirements for stress echocardiographic readings, 925 patients were evaluated after a mean of 10 days from an acute myocardial infarction and followed up for a mean of 14 months. RESULTS: During the follow-up, there were 34 deaths and 37 nonfatal myocardial infarctions; 104 patients developed class III or IV angina and 149 had coronary revascularization procedures (bypass or angioplasty). Considering all spontaneous events (angina, reinfarction, and death), the most important univariate predictor was the presence of an inducible wall motion abnormality after dipyridamole administration (chi 2 = 45.8). With a Cox analysis, echocardiographic positivity, age, and male gender were found to have an independent and additive value. Considering survival (and, therefore, death as the only event), age was the most meaningful parameter, followed by the wall motion score index during dipyridamole administration (chi 2 = 12.1). Among other parameters, the resting wall motion score index was a significant predictor of death. In a multivariate analysis, the prognostic contributions of age (relative risk estimate = 1.08) and wall motion score index during dipyridamole administration (relative risk estimate = 4.1) were independent and additive. In particular, considering death only, the event rate was 2% in patients with negative DET results, 4% in patients with positive high-dose DET results, and 7% in patients with positive low-dose DET results. CONCLUSIONS: DET is feasible and safe early after uncomplicated myocardial infarction and allows effective risk stratification on the basis of the presence, severity, extent, and timing of the induced dyssynergy.
Adult↗
Increased echodensity of transiently asynergic myocardium in humans: a novel echocardiographic sign of myocardial ischemia.
OBJECTIVES: This study was conducted to establish whether changes in myocardial texture can be observed in humans by transthoracic echocardiography during ischemic episodes of different severity and duration induced by various pathogenetic mechanisms. BACKGROUND: Increased echo-reflectivity of ischemic myocardium has been detected in experimental animals by epicardial echocardiography and by backscatter evaluation. METHODS: Transthoracic two-dimensional echocardiographic monitoring with a commercially available electronic sector scanner (2.25- or 3.5-MHz transducer) was performed during 35 episodes of transient myocardial ischemia induced by ergonovine in patients with vasospastic angina (n = 9), by dipyridamole in patients with angiographically assessed coronary artery disease (n = 11) and by balloon occlusion during coronary angioplasty (n = 15). Quantitative texture analysis of gray levels was performed off-line on digitized images during rest conditions, ischemia and the recovery phase in regions showing normal contraction at rest, obvious dyssynergy during ischemia and normal contraction in the recovery phase. In each condition, a control region with normal contraction throughout the study was also evaluated. RESULTS: Chest pain occurred in 23 of the 35 episodes; electrocardiographic (ECG) changes were present in 26 episodes, and consisted of ST segment elevation in 13, ST segment depression in 10 and pseudonormalization of a basally negative T wave in 3. The duration of ischemic episodes was 67 +/- 53 s by symptomatic criteria and 91 +/- 52 s by ECG criteria. The risk region showed an increased end-diastolic mean gray level amplitude in a.u. (arbitrary units) during ischemia (57 +/- 19) compared with rest (38 +/- 15) and recovery (38 +/- 18, p < 0.01). No significant changes were detected in the control region (rest 36 +/- 16 vs. ischemia 34 +/- 18 vs. recovery 31 +/- 13, p = NS). The percent increase in mean gray level was similar in the various types of stress employed (ergonovine, dipyridamole or angioplasty) and was not significantly correlated with either the duration of ST segment shift (r = 0.05, p = NS) or the severity of dyssynergy evaluated semiquantitatively by means of the wall motion score (r = 0.28, p = NS). In the 15 balloon occlusions performed in six patients during coronary angioplasty, the increased echoreflectivity of the risk zone was already evident during echocardiographic sampling performed after 10 +/- 4 s of occlusion (rest 35 +/- 9 vs. 53 +/- 10 a.u., p < 0.01) when no dyssynergy could be detected by quantitative wall motion analysis (percent area change by fixed center of mass reference system 31 +/- 10% at rest vs. 32 +/- 11% after 10 s of occlusion, p = NS). CONCLUSIONS: Transient short-lasting myocardial ischemia is associated with an abrupt increase in myocardial echodensity detectable by videodensitometric analysis applied to standard transthoracic echocardiographic images and is largely independent of the underlying pathogenetic mechanism (reduced blood supply or flow maldistribution with coronary stenosis). During controlled coronary occlusion, increased echodensity precedes the onset of regional dyssynergy.
Analysis of Variance↗
Prognostic value of dipyridamole echocardiography early after myocardial infarction in elderly patients. Echo Persantine Italian Cooperative (EPIC) Study Group.
OBJECTIVES: This study was conducted to assess the feasibility, safety and prognostic value of dipyridamole echocardiography in elderly patients recovering from an uncomplicated acute myocardial infarction in a subset analysis performed on the patients entered in the subproject "residual ischemia" of the Echo Persantine Italian Cooperative Study (EPIC). BACKGROUND: Coronary heart disease accounts for two thirds of all deaths in the age group > 65 years, and > 50% of all patients admitted to the hospital with acute myocardial infarction are > 65 years old. The prognostic value of dipyridamole-induced left ventricular dysfunction was clearly established in patients evaluated early after acute infarction. METHODS: In a subgroup analysis of the Echo Persantine Italian Cooperative Study (EPIC), we assessed the value of dipyridamole echocardiography in predicting cardiac events in 190 elderly (> or = 65 years) patients (age 68.4 +/- 3.3 years, range 65 to 78; 147 men and 43 women) evaluated early (mean 10 days) after uncomplicated acute myocardial infarction and followed up for 14 +/- 9.8 months. RESULTS: There was no major side effect during dipyridamole echocardiography. A positive test result occurred in 85 patients (44.7%). During follow-up, there were 62 events (14 cardiac deaths, 7 nonfatal reinfarctions, 21 cases of class III or IV angina and 20 revascularization procedures). Of these 62 events, 44 occurred among 85 patients with positive dipyridamole echocardiography and 18 among 105 patients with negative dipyridamole echocardiography (52% vs. 17%, p < 0.001). Spontaneous events (death, reinfarction, angina) occurred in 31 patients with positive and in 11 with negative dipyridamole echocardiography (36% vs. 10%, p < 0.001). Hard events (myocardial infarction or death) occurred in 14 patients with positive and 7 with negative dipyridamole echocardiography (16% vs. 6%, p < 0.05). Death occurred in 11 patients with positive and in 3 with negative dipyridamole echocardiography (13% vs. 3%, p < 0.01). The positive predictive value of positive dipyridamole echocardiography and negative predictive value of negative dipyridamole echocardiography as related to the occurrence of all events in the follow-up period (death, reinfarction, angina, revascularization procedures) were 52% and 83%, respectively. The relative risk (that is, the relative risk of occurrence of future cardiac events in the group with positive dipyridamole echocardiography compared with that in those with negative dipyridamole echocardiography) was 3 for all events and 4.4 for death. CONCLUSIONS: Dipyridamole echocardiography was well tolerated by elderly patients and proved to be very effective in prognostic stratification early after uncomplicated acute myocardial infarction, even when only survival was considered.
Aged↗
Effects of coronary blood flow on myocardial grey level amplitude in two dimensional echocardiography: an experimental study.
OBJECTIVE: The aims were: (1) to evaluate whether differences in absolute and cyclic echocardiographic image amplitude exist in different layers (subendocardium and subepicardium) and regions (septal, anterior, lateral, inferior wall) of the canine left ventricle; (2) to assess the dependence of these variables upon local variations of coronary blood flow. METHODS: In six anaesthetised open chest dogs the circumflex coronary artery was cannulated and perfused by a roller pump with blood from their own femoral artery. Maximum coronary vasodilatation was obtained by continuous adenosine infusion. The absolute values and the transmural distribution of coronary blood flow were measured by radionuclide labelled microspheres. Echo images were obtained in short axis view by a commercially available electronic sector scanner with a 5.0 MHz transducer directly placed on the epicardial surface of the right ventricle, and digitised off-line into a matrix of 256 x 256 pixels with 25% grey level per pixel. The average grey level was calculated for each region of interest. RESULTS: In 32 different conditions, circumflex flow ranged from 0.80 to 12.89 ml.min-1.g-1 and the endocardial/epicardial ratio of flow from 0.53 to 1.73. In the circumflex region (subjected to flow changes) segmental amplitude varied from 76(SD 20) (end diastole) to 56(18) (end systole), p < 0.001. In all regions, a consistent cyclic variation was found, ranging from 9(14) to 28(16)%. For all levels of flow, subendocardial and subepicardial regions showed similar values of both absolute amplitude and cyclic variation. No significant relationship was found between transmural distribution of blood flow and either segmental amplitude (r = 0.26) or cyclic variation (r = 0.04). CONCLUSIONS: (1) a consistent cyclic grey level variation is present in all regions of the canine left ventricle, but subendocardial and subepicardial layers show similar values of both absolute amplitude and cyclic variation; (2) in the absence of severe underperfusion and echocardiographically detectable dyssynergy, absolute amplitude and cyclic variation are totally unrelated to changes in coronary blood flow.
Animals↗
Left ventricular performance and ultrasonic myocardial quantitative reflectivity in endurance senior athletes: an echocardiographic study.
Young elite athletes often show left ventricular hypertrophy, but normal values of quantitatively evaluated myocardial wall reflectivity. The aim of this study is to assess the acoustic pattern of ventricular wall reflectivity, as well as of systolic and diastolic function, in older endurance runners with increased left ventricular mass. For this purpose, 12 elite, senior isotonic athletes in full training and 11 normal, age-matched controls with sedentary life styles were studied. The following parameters were measured with a commercially available 2D echo-Doppler machine: end-diastolic diameter, diastolic septum thickness, left ventricular mass index, ejection fraction (by Teicholtz rule); peak E, peak A, E/A ratio, acceleration and deceleration time of mitral inflow velocity and isovolumic relaxation time. On-line radio frequency analysis was also performed to obtain quantitative operator-independent measurements of the integrated backscatter signal of the ventricular septum and the posterior wall. The integrated values of the radiofrequency signals were normalized for the pericardial interface and expressed in percent (% 2D-IB). In spite of the greater left ventricular mass in athletes versus normal controls (319 +/- 81 vs 225 +/- 63 g.m-2, P < 0.0005), there were no significant intergroup differences as regards end-diastolic diameter (50.7 +/- 5.1 vs 48.1 +/- 5.2 mm, P = ns), ejection fraction (75.5 +/- 9.3 vs 71.8 +/- 9.1%, P = ns), and 2D-IB of septum (22.2 +/- 6.9 vs 22.4 +/- 7.0, P = ns) and posterior wall (12.5 +/- 5.6 vs 13.1 +/- 2.8, P = ns).(ABSTRACT TRUNCATED AT 250 WORDS)
Aged↗
Enhanced sensitivity for detection of coronary artery disease by addition of atropine to dipyridamole echocardiography.
Dipyridamole echocardiography test (DET) has gained acceptance due to its safety, feasibility, diagnostic accuracy and prognostic power. The main limitation of the test is a less than ideal sensitivity in some patient subsets, such as those with limited coronary artery disease. Atropine with dipyridamole might theoretically combine to become a synergistic ischaemic stress test, by increasing myocardial oxygen demand through chronotropic stress and by reducing flow supply through a shortening of the diastolic interval under maximal coronary vasodilation. The aim of this study was to assess the effects of the addition of atropine to DET. Three hundred and twenty-one patients (age = 58 +/- 9 years), referred for testing in the echo lab, were initially studied by DET. Of these, 151 were stopped during or within the 2 min following dipyridamole infusion because of achievement of a predetermined end-point: obvious echocardiographic positivity (n = 137), severe chest pain (n = 3), diagnostic ST segment changes (n = 7) or limited side effects (n = 4). In another three cases, atropine was not given due to a history of glaucoma or severe prostatic hypertrophy. In the remaining 167 patients with a negative DET test, atropine (0.25 mg intravenously, repeated every min up to a maximum of 1 mg, if necessary) was added, starting 3 min after the end of the dipyridamole infusion. The dipyridamole-atropine echo test (DETA) was positive in 32 and negative in 135 patients, and no major side effects occurred in any patient.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Quantitative ultrasonic analysis of myocardium in patients with thalassemia major and iron overload.
BACKGROUND: Patients with beta-thalassemia major present with severe anemia and need continuous transfusion therapy. The consequent iron overload leads to hemochromatosis. Initial cardiac dysfunction has been documented even in thalassemics without clinical manifestations of heart failure as well as by conventional echocardiographic-Doppler techniques. The purpose of this study was to assess the acoustic quantitative properties of myocardium in patients with iron overload. METHODS AND RESULTS: Thirty-eight patients with beta-thalassemia major, without clinical signs of cardiac failure, and 20 age- and sex-matched young controls were studied by echocardiography. An on-line analysis of the ultrasonic radiofrequency signal was performed to obtain quantitative operator-independent measurements of the integrated backscatter (IB) signal of the ventricular septum and the posterior wall. The integrated values of the radiofrequency signal were normalized for the pericardial interface and expressed in percent (IB%). Thalassemic patients had been receiving transfusion therapy for 16 +/- 5 years and had received 313 +/- 138 transfusion units; they all had received chelation treatment (desferroxiamine) for 9 +/- 2 years. Patients and controls showed comparable values of echocardiographically assessed percent fractional shortening (32 +/- 3% versus 36 +/- 4%, p = NS), whereas thalassemics showed higher values of left ventricular mass index (118 +/- 30 versus 98 +/- 15 g/m2, p < 0.05). The IB% values were higher in patients with thalassemia major than in controls for both septum (35 +/- 14% versus 21 +/- 6%, p < 0.001) and posterior wall (16 +/- 6% versus 11 +/- 3%, p < 0.001). In thalassemic patients, no significant correlation was found between the septum IB% value and hematological parameters, such as the total number of transfusions (r = 0.2, p = NS) or the mean ferritin value (r = 0.1, p = NS). No significant correlation was also found between the septum IB% value and the echocardiographically assessed left ventricular mass index (r = 0.2, p = NS). CONCLUSIONS: These data demonstrate that myocardial reflectivity is abnormally increased in patients with thalassemia major under transfusion treatment, probably due to myocardial iron deposits and/or secondary structural changes. These quantitatively assessed abnormalities in regional reflectivity can be detected when conventional echocardiographic parameters of systolic left ventricular function are undistinguishable from normal controls.
Adolescent↗
Normal ultrasonic myocardial reflectivity in hypertensive patients. A tissue characterization study.
Ultrasonic backscatter of myocardial walls is directly related to the morphometrically evaluated collagen content in humans. The integrated backscatter is also increased in hypertrophic cardiomyopathy, whereas it gives normal values in the physiological hypertrophy of elite athletes. We assessed the quantitatively evaluated myocardial reflectivity in 46 mild to moderate, clinically uncomplicated essential hypertensive patients, with echocardiographically assessed normal regional and global left ventricular function, and 22 age- and sex-matched normotensive control subjects. With an echo prototype implemented in our institute, we performed an on-line radiofrequency analysis to obtain quantitative operator-independent measurements of the integrated backscatter signal of the ventricular septum and posterior wall. The integrated values of the radiofrequency signal of myocardial walls were normalized for those of the pericardial interface and expressed as a percent (integrated backscatter index). Hypertensive patients and control subjects differed in mean blood pressure (119 +/- 11 versus 95 +/- 5 mm Hg, p < 0.001) and left ventricular mass index (134 +/- 31 versus 105 +/- 21 g/m2, p < 0.001). However, integrated backscatter index overlapped for both the septum (28 +/- 17% versus 25 +/- 6%, p = NS) and the posterior wall (13 +/- 7% versus 13 +/- 4%, p = NS). In the hypertensive group, there was no detectable correlation between septal integrated backscatter index and either septal thickness (r = -0.26, p = NS) or mean arterial pressure (r = -0.14, p = NS). Hypertensive patients showed a normal pattern of quantitatively assessed ultrasonic backscatter, even in the presence of left ventricular hypertrophy.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
In vivo radiofrequency-based ultrasonic tissue characterization of the atherosclerotic plaque.
BACKGROUND AND PURPOSE: The ultrasonic image can offer unique information on the composition of atherosclerotic plaque, ie, the relative content of lipids, fibrous tissue, and calcific deposits. To date, however, the echographic assessment of plaque structure is based on a subjective, qualitative evaluation of the bidimensional images. We evaluated the feasibility and accuracy of assessing, in vivo, the acoustic properties of arterial carotid plaques by means of a suitably modified echographic apparatus allowing direct access to the radiofrequency signal. METHODS: In 15 patients undergoing carotid thromboendarterectomy, the ultrasonic findings in 70 discrete sites (within the plaque, n = 54; normal sites, n = 11; or intraluminal thrombi, n = 5) were correlated with the histological analysis (hematoxylin-eosin and Mallory trichrome stains) independently performed on the arterial samples. The pathological examination was carried out at a similar level of the insonation; the sites analyzed within the plaque were chosen because of their uniform echoic characteristics. In each ultrasonic region of interest selected from the echographic image, the integrated amplitude of the rectified radiofrequency signal was measured as the integrated backscatter index. RESULTS: The intimal-medial layer of normal carotid wall (n = 11) exhibited values of -32.5 +/- 9.4 dB. The integrated backscatter index in fatty sites (n = 11, -40.3 +/- 5.4 dB) differed from that of fibrous (n = 12, -23.8 +/- 5.0 dB) and calcified (n = 26, -11.5 +/- 5.2 dB, P < .01 for all intergroup differences) sites. Intraluminal thrombotic sites (n = 5, -42 +/- 5.1 dB, P < .01) differed from fibrous and calcified subsets (P < .01) but overlapped (P = NS) with fatty sites. Histological sampling also showed two sites of intraplaque hemorrhage that exhibited very low backscatter values (-53 and -58 dB) and three fibrofatty sites showing backscatter values (-28, -28, and -32 dB) intermediate between the fibrous and the fatty subsets. CONCLUSIONS: Quantitative analysis of integrated backscatter of the arterial wall is feasible in humans and provides an operator-independent assessment of plaque echoic structure. In particular, integrated backscatter is effective in distinguishing lipidic, fibrotic, and calcific components in human atherosclerotic plaques.
Arteriosclerosis↗
Imaging of myocardial viability: a head-to-head comparison among nuclear, echocardiographic, and angiographic techniques.
The relationship between radioisotopic, echocardiographic, and angiographic markers of myocardial viability is still to be defined. To this purpose, 14 patients with previous myocardial infarction were studied using a multiparametric approach. Each patient underwent, on separate days, rest thallium 201 and technetium 99m Sestamibi planar scintigraphy, dobutamine/dipyridamole stress echocardiography, and coronary angiography; 11 of these patients underwent also dipyridamole echocardiographic testing. Thallium 201 and Sestamibi uptakes at rest were expressed as percentage of maximal activity in each projection using a 13 segment model. Dobutamine and dipyridamole stress echocardiography were analyzed using a score index ranging from 1 (normokinesis) to 4 (dyskinesis) and a similar segmentation. Coronary angiography was analyzed by quantitative approach. In all patients, follow-up echocardiography was performed following coronary revascularization. Before revascularization, 75 segments showed regional dyssynergies. Thallium 201 showed the highest sensitivity and specificity in the preoperative identification of viability, whereas Sestamibi was affected by a significant number of false-negative studies. Among echocardiographic techniques, dobutamine was slightly superior to dipyridamole in the detection of viable segments. The degree of coronary stenosis failed to predict the recovery of function following by-pass graft or angioplasty in almost all segments; however, in case of occlusion, most viable segments were perfused by adequately collateralized coronary arteries.
Adult↗
[The myocardium at risk in transient ischemia: its assessment by echocardiography].
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Coronary Circulation↗
[Provocative tests of myocardial ischemia: the current scenario].
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Heart Function Tests↗
Identification of viable myocardium by dipyridamole-induced improvement in regional left ventricular function assessed by echocardiography in myocardial infarction and comparison with thallium scintigraphy at rest.
In patients with coronary artery disease and left ventricular impairment, the distinction between ventricular dysfunction due to myocardial fibrosis and postischemic, viable, although dys-synergic, myocardium has important clinical implications. Experimental studies have shown that dipyridamole can increase myocardial function in stunned segments, outlining a potential role of dipyridamole-induced functional recovery as an ultrasonic marker of myocardial viability. The aim of this study was to assess whether the increase of regional left ventricular function early during dipyridamole infusion in basally asynergic segments could identify viable myocardium recognized by rest injected, delayed (greater than 14 hours from tracer injection) thallium and (in a subset of patients) late functional recovery evaluated by a follow-up echocardiogram at rest. Twenty-two patients with angiographically documented coronary artery disease and regional dysfunction in resting conditions (average left ventricular ejection fraction 43 +/- 8%) were studied by echocardiography. All patients underwent a dipyridamole-echocardiographic test (up to 0.84 mg/kg over 10 minutes) and a delayed planar thallium study. A 13-segment model was used for both techniques. A score index ranging from 1 (normokinesia) to 4 (dyskinesia) was used for echocardiography. Thallium-201 activity was expressed in each segment as the percentage of maximal activity in the corresponding view. After dipyridamole, the wall motion score was assigned to each segment in resting conditions and at peak hyperkinesia before possible mechanical signs of ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)
Coronary Angiography↗
Safety of intravenous high-dose dipyridamole echocardiography. The Echo-Persantine International Cooperative Study Group.
Clinical data on 10,451 high-dose (up to 0.84 mg/kg over 10 minutes) dipyridamole-echocardiography tests (DET) performed in 9,122 patients were prospectively collected from 33 echocardiographic laboratories, each contributing greater than 100 tests. All patients were studied for documented or suspected coronary artery disease (1,117 early [less than 18 days] after acute myocardial infarction and 293 had unstable angina). Significant side effects including major adverse reactions and minor but limiting side effects occurred in 113 patients (1.2%). Major adverse reactions occurred in 7 cases (0.07%). In 6 of these cases, adverse reactions were associated with echocardiographically assessed ischemia and included 1 prolonged cardiac asystole (complicated by acute myocardial infarction and coma, with death after 23 days), 1 short-lasting cardiac asystole, 2 myocardial infarctions, 1 pulmonary edema and 1 sustained ventricular tachycardia. In all 6 cases, the cardiologist-echocardiographer performing the study had a limited experience (less than 100 tests) with DET, and at off-line reading in 5 cases, the obvious echo-positivity preceded the onset of complications by 1 to 5 minutes. The only ischemia-independent major side effect was a short-lasting cardiac asystole that was reversed by aminophylline and atropine. Significant side effects associated with echocardiographically assessed ischemia occurred in 89 additional cases (21 with and 68 without concomitant echocardiographically assessed myocardial ischemia). The most frequent of these side effects was hypotension or bradycardia, or both, which occurred in 40 patients with negative and 6 with positive DET. In all cases, side effects promptly subsided after aminophylline. In 1,857 cases, the high dose was not given for echo-positivity before the eighth minute.(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
Dipyridamole-echocardiography: clinical usefulness following interventions.
Dipyridamole-echocardiography test response can be expressed not only in a black or white (positive vs negative) code but also, in positive tests, by a gray scale integrating the severity and extent of the dyssynergy as well as the ischemia-free stress time. The recognition of the dyssynergy is important to establish the diagnosis; however, the evaluation of the degree of the induced ischemia, stratified according to spatiotemporal coordinates, is even more important because it accurately predicts the coronary anatomical and functional situation, as well as the prognosis of the individual patient. Furthermore, the "shades of gray" in a positive response have proved useful in assessing the beneficial effects of several interventions: coronary angioplasty; coronary artery bypass surgery; thrombolysis; and medical antianginal therapy. Due to its excellent reproducibility, dipyridamole-echocardiography can play a pivotal role for simple, safe, fast, accurate, and objective assessment of therapeutic interventions, either mechanical or pharmacological, based upon the presence, timing, severity, and extent of dipyridamole-induced dyssynergy.
Angina Pectoris↗