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PubMed1986

Dipyridamole versus intracoronary injection of contrast medium for the evaluation of coronary reserve in man: a comparative study.

Coronary reserve can be assessed by the ratio of coronary blood flow after "maximum" vasodilation to control flow. The intravenous infusion of dipyridamole (0.56 mg X kg-1) is considered to elicit maximum coronary vasodilation. The present study was designed to compare coronary flow and resistance responses to intravenous dipyridamole and intracoronary injection of contrast medium (ioxaglate), this latter technique being frequently used in digital radiology to stimulate hyperemia. The comparison was performed in seven normal patients, nine patients with coronary artery disease, and 16 patients with dilated cardiomyopathy. Coronary flow reserve was calculated as the ratio of peak flow after dipyridamole or contrast medium to control flow, and coronary resistance reserve was calculated as the ratio of minimal to control coronary resistance after each stimulus. Although flow reserve after dipyridamole was approximately twice that obtained after contrast medium in the normal group (4.01 +/- 0.56 vs 2.02 +/- 0.24) there was a close and linear relationship between coronary flow and resistance reserve estimated by both techniques (r = 0.846, p less than 0.001 for flow reserve ratios, and r = 0.844 p less than 0.001 for resistance reserve ratios). However, contrast-induced hyperemia identified 13/25 (52%) of patients with coronary artery disease or dilated cardiomyopathy as having a reduced flow reserve, while dipyridamole revealed a restrained coronary flow reserve in 20/25 (80%) of these patients. Similar proportions were obtained when using coronary resistance reserve (56% for contrast vs 80% for dipyridamole). (ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1986

Effect of nifedipine on dipyridamole thallium-201 myocardial scintigraphy.

The effect of a calcium antagonist drug, nifedipine, on dipyridamole thallium-201 images was assessed in 10 angina patients with positive dipyridamole test. Two dipyridamole thallium-201 tests were performed, the first in basal conditions, the second after administration of 20 mg nifedipine. After dipyridamole, heart rate and double product increased respectively from 68.0 +/- 8.2 to 94.7 +/- 11.5 beats/min (p less than 0.01) and from 9459.5 +/- 1800.2 to 12,770.0 +/- 1864.7 mmHg X beats/min (p less than 0.01). Dipyridamole when infused after nifedipine induced an increase in heart rate from 74.2 +/- 7.16 to 88.8 +/- 5.6 beats/min (p less than 0.01) and in double product from 9650.5 +/- 1348.0 to 11,399.0 +/- 1146 mmHg X beats/min (p less than 0.05). Systolic and diastolic blood pressures were unmodified during the two studies. Segment scores were comparable before and after nifedipine. Thus, nifedipine does not worsen thallium-201 myocardial images obtained during dipyridamole infusion, therefore, this test could provide an alternative to exercise thallium-201 in patients receiving calcium antagonist drugs.

Coronary Circulation↗

PubMed1986

Two-dimensional echocardiographic evaluation of ventricular asynergy induced by dipyridamole: correlation with thallium scanning.

Myocardial asynergies detected by two-dimensional echocardiography during intravenous administration of Dipyridamole (0.75 mg/kg) were evaluated in 54 patients referred for angiographic evaluation of chest pain. Technically adequate two-dimensional echocardiograms suitable for analysis were recorded in 42 of 54 (77.7%) patients studied. Thallium-201 myocardial perfusion scintigraphy, during dipyridamole test was performed in the same patients. Thirty of the 42 patients studied showed significant coronary narrowing at cardiac catheterization. Dipyridamole-induced wall motion abnormalities and myocardial perfusion defects were detected, respectively, in 19 (63.3%) and 21 (70%) of 30 patients with significant coronary artery disease. Wall by wall comparison of the distribution of dipyridamole-induced echocardiographic asynergy with reversible thallium-201 (201Tl) perfusion defects demonstrated complete correlation in 42 segments examined. Three segments with perfusion defects at thallium scanning did not show asynergy during the test while two segments showing wall motion abnormalities during dipyridamole infusion did not manifest perfusion defects. Our study demonstrates that two-dimensional echocardiography during dipyridamole testing is useful in detecting patients with coronary artery disease. Furthermore, ventricular asynergies detected during the test show a high correspondence with site of myocardial perfusion defects at thallium scanning.

Cardiac Catheterization↗

PubMed1990

Thallium-201 perfusion imaging with atrial pacing or dipyridamole stress testing for evaluation of cardiac risk prior to nonvascular surgery.

Preoperative assessment of cardiac risk using thallium-201 scintigraphy and atrial pacing (n = 42) or dipyridamole stress testing (n = 35) was performed in 77 patients (mean age 65 +/- 7 years), who subsequently underwent elective nonvascular surgery. All patients were at low cardiac risk by clinical criteria; none could perform exercise stress testing due to physical limitations. ST depression consistent with ischemia occurred in 11 patients during atrial pacing and in 1 patient during dipyridamole stress testing (p less than 0.01). Nine patients had reversible perfusion defects with atrial pacing, and 10 patients with dipyridamole stress testing; fixed defects were present in 15 and 8 patients, respectively. Only one patient (fixed perfusion defect with atrial pacing, left main disease on coronary angiography) underwent preoperative coronary revascularization. Two patients subsequently had postoperative cardiac events. One patient (reversible perfusion defect with dipyridamole stress testing) experienced sudden death after a nonvascular procedure, while a second patient (normal thallium images with dipyridamole testing) had a nonfatal myocardial infarction. In patients having atrial pacing or dipyridamole stress testing, thallium-201 scans that are normal or show only a fixed perfusion defect confirm a low risk of cardiac complications following nonvascular surgery. The presence of a reversible perfusion defect does not preclude a postoperative course free of cardiac complications in patients at low cardiac risk by clinical criteria.

Aged↗

PubMed2002

Correlation between myocardial perfusion abnormalities detected with intermittent imaging using intravenous perfluorocarbon microbubbles and radioisotope imaging during high-dose dipyridamole stress echo.

BACKGROUND: The clinical accuracy of myocardial contrast echocardiography (MCE) using intermittent harmonic imaging and intravenous perfluorocarbon containing microbubbles during dipyridamole stress has not been evaluated in a multicenter setting. HYPOTHESIS: The accuracy of dipyridamole stress contrast echo in the detection of coronary artery disease (CAD) using myocardial perfusion images is high in comparison with technetium-99 (99Tc) sestamibi single-photon emission computed tomography (MIBI SPECT) and increases the accuracy of wall motion data. METHODS: In 68 consecutive nonselected patients (46 men; mean age 66 years) from three different institutions in two countries. dipyridamole stress echo and SPECT with 99mTc MIBI were compared. Continuous intravenous (IV) infusion of perfluorocarbon exposed sonicated dextrose albumin (PESDA) (2-5 cc/min) was administered for baseline myocardial perfusion using triggered harmonic end systolic frames. Real-time digitized images were used for wall motion analysis. Dipyridamole was then injected in two steps: (1) 0.56 mg/kg for 3 min, (2) 0.28 mg/kg for 1 min, if the first step was negative for an inducible wall motion abnormality. After dipyridamole injection, myocardial contrast enhancement and wall motion were analyzed again by the same methodology. RESULTS: There were 35 patients with perfusion defects by SPECT. Wall motion was abnormal in 22, while MCE was abnormal in 32. Wall motion and MCE each had one false positive. The proportion of correctly assigned patients was significantly better with MCE than with wall motion (p = 0.03; chi square test). CONCLUSIONS: Myocardial contrast echocardiography, using intermittent harmonic imaging and intravenous perfluorocarbon containing microbubbles, is a very effective method for detecting coronary artery disease during dipyridamole stress echo.

Adult↗

PubMedDate not supplied

Plasma dipyridamole concentrations after two different dosage regimens in patients.

Twenty patients received dipyridamole by two different dosage regimens yielding a total daily dose of 150 mg, either as 50 mg three times a day or 75 mg twice a day. The rationale for comparing these two regimens is that dipyridamole is usually given three times a day, but recent studies have revealed a final elimination half-life of the drug of about half a day. Based on drug cumulation during chronic dosing, the final half-life of dipyridamole observed in this study also averaged about half a day. The 75 mg b.i.d. regimen did not result in lower trough concentrations than the 50 mg t.i.d. regimen. There was wide interpatient variability in observed plasma dipyridamole concentrations for both regimens, averaging about 10-fold. These results suggest that dipyridamole could be administered twice a day and that dipyridamole levels should be monitored in clinical studies on the antithrombotic effect of the drug.

Dipyridamole↗

PubMed2006

Development of a sustained-release system for perivascular delivery of dipyridamole.

Vascular access grafts implanted in dialysis patients are prone to failure in the long-term because of stenosis and occlusion caused by neointimal hyperplasia. Local delivery of antiproliferative drugs may be effective to prevent this consequence while minimizing the systemic side effects they cause. We developed a combination of poly(lactide-co-glycolide) (PLGA) microspheres with ReGel, an injectable copolymer, as a sustained-release system for perivascular delivery of an antiproliferative drug, dipyridamole. Dipyridamole-incorporated PLGA microspheres with various molecular weights (MWs) of PLGA were prepared by oil-in-water emulsion method. Encapsulation efficiency and surface morphology of microspheres were characterized. In vitro release kinetics of dipyridamole from ReGel or from microspheres/ReGel was experimentally determined. Without microspheres, 40% of the dipyridamole was released from ReGel as an initial burst in the first 3 days followed by continuous release in the subsequent 2 weeks. The use of PLGA microspheres decreased the initial burst and extended dipyridamole release from 23 to 35 days with increasing MW of PLGA. The highest MW PLGA showed a lag time of 17 days before consistent drug release occurred. Mixing microspheres and ReGel with two different MW PLGA achieved a continuous release for 35 days with little initial burst. In vivo release of dipyridamole from microspheres/ReGel exhibited a comparable release pattern to that seen in vitro. This injectable platform is a promising technique for sustained perivascular delivery of antiproliferative drugs.

Animals↗

PubMed1994

The type III phosphodiesterase inhibitor milrinone and type V PDE inhibitor dipyridamole individually and synergistically reduce elevated pulmonary vascular resistance.

The effects of the phosphodiesterase (PDE) inhibitors milrinone and dipyridamole were studied in an in situ perfused rabbit lung model in which the pulmonary vascular resistance (PVR) was elevated by infusion of the thromboxane-A2 mimetic U46619. Dose-response curves for reduction of elevated PVR were generated for each of these drugs. The EC50 for milrinone was approximately 2 microM. The EC50 for dipyridamole was approximately 0.2 microM. In separate experiments, 0.1 microM milrinone was found to reduce elevated PVR by 4.6 +/- 2.4%, 0.06 microM dipyridamole reduced elevated PVR by 8.2 +/- 2.8%, whereas the combination of 0.1 microM milrinone and 0.06 microM dipyridamole reduced elevated PVR by 41.9 +/- 7.3%. In more limited experiments, it was determined that the PDE type V inhibitor zaprinast also caused a synergistic reduction of PVR when used with milrinone. We concluded that both the type III PDE inhibitor milrinone and the type V PDE inhibitors dipyridamole or zaprinast are effectively able to reduce elevated PVR and that the combination of PDE type III and type V inhibitors is synergistic in the ability to reduce elevated PVR. We speculate that type V PDE may play a more important role than type III PDE in the regulation of pulmonary vascular tone. It is proposed that the combination of milrinone and dipyridamole has the potential to be useful in the clinical treatment of elevated PVR.

Animals↗

PubMed1992

A comparison of maximal exercise and dipyridamole thallium-201 planar gated scintigraphy.

Both symptom-limited maximal exercise and intravenously given dipyridamole stress (0.56 mg/kg over 4 min with a 2 min walk) gated thallium scans were performed in 22 patients undergoing coronary arteriography for the assessment of chest pain. All scans were acquired gated to the electrocardiogram in 3 projections and were reported for the presence and extent of defects in 5 myocardial segments in each view. In addition, left and right ventricular myocardial uptake and estimates of right and left lung and liver to left ventricular uptake were assessed relative to the injected dose of thallium-201. Overall, 190/310 segments were abnormal with exercise compared with 169/310 with dipyridamole. Segments were scored greater in extent in 90/310 cases with exercise, compared with 46/310 in which the defect was more extensive with dipyridamole (P less than 0.0005). Non-attenuation corrected percentage myocardial thallium uptakes were similar for both stresses: anterior percentage uptakes, 0.785% +/- 0.230% with exercise versus 0.870% +/- 0.217% with dipyridamole (NSD). Left and right lung and liver to left ventricle ratios were all significantly higher with dipyridamole than with exercise (1.587 +/- 0.408 versus 1.446 +/- 0.518, P less than 0.02; 1.78 +/- 0.479 versus 1.46 +/- 0.502, P less than 0.002; 2.598 +/- 0.788 versus 1.265 +/- 0.386, P less than 0.001, respectively). High right and left lung uptakes with dipyridamole were strongly correlated with high exercise values (r = 0.756, P less than 0.001; r = 0.809, P less than 0.001). The liver uptake was weakly correlated between the 2 different stress tests (r = 0.483, P less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1982

Myocardial imaging with dipyridamole: comparison of the sensitivity and specificity of 201Tl versus MUGA.

Myocardial imaging was performed at rest and after dipyridamole infusion using 201Tl and 99Tcm - gated blood pool studies (MUGA). Of 38 patients studied, 21 had coronary artery disease (CAD) and 17 were normal. With 201Tl imaging, 19 of 21 patients with CAD (sensitivity 88%) showed perfusion defects during dipyridamole. Of 17 normals 6 (specificity 65%) showed clear perfusion defects during dipyridamole. With MUGA, 2 of 15 patients with CAD (sensitivity 13%) developed abnormal wall motion during dipyridamole; both patients developed ST depression greater than 1 mm. Of 10 normals none developed abnormal wall motion. Twenty six of 38 patients developed angina during dipyridamole, which was reversed by aminophylline in 24 of 26. We suggest that dipyridamole infusion is effective for 201Tl-perfusion imaging, and easily performed, but is not suitable for MUGA studies where ischaemia is the required endpoint.

Aminophylline↗

PubMed1992

Schedule-dependent synergistic action of tiazofurin and dipyridamole on hepatoma 3924A cells.

Tiazofurin is an oncolytic nucleoside analog that has shown therapeutic activity in end-stage acute non-lymphocytic leukemia and in chronic granulocytic leukemia in blast crisis. Tiazofurin is anabolized to the active metabolite, TAD, which inhibits IMP dehydrogenase activity, leading to a reduction in guanylate pools and to the cessation of neoplastic cell proliferation. The drug exhibits potent cytostatic and cytotoxic activity against hepatoma 3924A cells in culture. In growth-inhibition and clonogenic assays, the 50% inhibitory concentration of tiazofurin was 3.8 and 4.2 microM, respectively. Dipyridamole, an inhibitor of nucleoside transport, curtails the salvage of nucleosides and bases for nucleotide biosynthesis. Dipyridamole exhibited cytotoxicity against hepatoma 3924A cells, with an LC50 of 24 microM and an IC50 of 29 microM being recorded. A combination of tiazofurin and dipyridamole provided synergistic cytotoxicity in hepatoma 3924A cells in culture. This synergistic activity was dependent on the order of addition of the drugs. Simultaneous addition of the two drugs produced antagonism, whereas preincubation of cells with tiazofurin or dipyridamole followed by addition of the second drug resulted in synergy. TAD concentrations were significantly higher (129% and 135%) in cells that had been pretreated with tiazofurin or dipyridamole before the addition of the second agent as compared with cells that had been treated simultaneously (113%). These studies indicate the importance of the order of the addition of drugs to obtain a synergistic response in combination chemotherapy and suggest the need for a careful selection of drug modulation in clinical trials of tiazofurin and dipyridamole.

Animals↗

PubMed1994

Phase I/II trial of dipyridamole, 5-fluorouracil, leukovorin, and mitoxantrone in metastatic breast cancer.

Based upon the hypothesis that dipyridamole would potentiate the cytotoxicity of mitoxantrone and the combination of 5-fluorouracil (5-FU) and leukovorin, we performed a phase I/II trial of the combination of dipyridamole, 5-FU, leukovorin, and mitoxantrone in patients with metastatic breast cancer. The dose of dipyridamole was fixed at 175 mg/m2 by mouth every 6 h (700 mg/m2/day), based upon a previous phase I trial of oral dipyridamole with 5-FU and leukovorin. Dipyridamole therapy began 24 h prior to the first dose of chemotherapy and continued until 24 h after the last dose of chemotherapy for each course of treatment. At the initial dose level, leukovorin 200 mg/m2 was given intravenously immediately prior to 5-FU 375 mg/m2 intravenously on days 1-5. Mitoxantrone 6 mg/m2 was given as a single dose on day 3. Unacceptable toxicity was observed at this dose level, leading to successive dose decrements rather than dose increments. The maximum tolerated dose was leukovorin 200 mg/m2 days 1-2, 5-FU 375 mg/m2 days 1-2, mitoxantrone 6 mg/m2 on day 2, and dipyridamole 175 mg/m2 every 6 h on days 0-3. Two responses were produced in 15 patients. This regimen is not recommended for further investigation in the treatment of breast cancer.

Adult↗

PubMed2006

Perivascular tissue pharmacokinetics of dipyridamole.

PURPOSE: The tissue diffusivity (D(g)) and partitioning (K) for dipyridamole were determined and a model was developed to examine the relationship between perivascular dose and local dipyridamole tissue concentrations. METHODS: Experiments were performed using an in vitro perfusion apparatus that recirculated buffer through different graft samples or normal porcine femoral arteries and veins. The grafts or blood vessels were immersed in a compartment containing Krebs-Henseleit (KH) buffer and dipyridamole (30 microg/mL). The recirculating buffer was sampled at multiple time points and dipyridamole was assayed. Estimates of the effective diffusivity (D(g)) and partition coefficient (K) of the drug in the vessel wall were determined and used to simulate dipyridamole tissue concentration after perivascular delivery. RESULTS: Dipyridamole diffusivity within native femoral veins (D(g) = 3.87 +/- 0.93 x 10(-6) cm2/s) was approximately twice that within femoral arteries (D(g) = 2.06 +/- 0.79 x 10(-6) cm2/s, p < 0.01). Explanted grafts showed the lowest diffusivity. Partition coefficients of femoral arteries (K = 4.11 +/- 0.99) were higher than those of femoral veins (K = 2.05 +/- 0.85, p < 0.01) and explanted graft (K = 0.89 +/- 0.56, p < 0.01). DISCUSSION: The results demonstrate that local drug kinetics vary greatly for different types of blood vessels and grafts. The pharmacokinetic parameters and resulting computational simulations are helpful in exploring perivascular drug delivery strategies.

Algorithms↗

PubMed1983

Effects of oral dipyridamole on coronary dynamics and myocardial metabolism at rest and during pacing-induced angina in patients with coronary artery disease.

The effects of oral dipyridamole administration (150 mg) on coronary hemodynamics, myocardial metabolism, and pacing threshold were studied in 10 patients with significant coronary artery disease (CAD). Following dipyridamole through 120 minutes, there was no significant change in resting heart rate, arterial pressure, coronary venous flow, coronary resistance, myocardial lactate extraction, or myocardial oxygen consumption. Rapid atrial pacing performed before and at 60, 90, and 120 minutes after dipyridamole failed to demonstrate any significant reduction in pacing threshold or evidence of increased ischemia after dipyridamole. Blood dipyridamole levels showed variable and slow absorption which probably explains the difference between intravenous and oral dipyridamole on coronary dynamics and myocardial response to pacing.

Administration, Oral↗

PubMed1989

Dipyridamole thallium-201 imaging pre- and post-coronary angioplasty for assessment of regional myocardial ischemia in humans.

To examine the effect of coronary angioplasty on myocardial perfusion and to examine anatomic correlates of dipyridamole-thallium images, we performed dipyridamole thallium scanning before and after 24 angioplasty procedures in 23 patients with clinical ischemia. Dipyridamole thallium tomography was performed 1 to 4 (mean +/- S.D. 1.5 +/- 0.9) days before and 1 to 25 (6.3 +/- 6.9) days after angioplasty. Coronary angioplasty was anatomically successful (less than 50% residual stenosis) in 23 of 24 patients. Before angioplasty, 3 of 24 scans were interpreted as normal, with no change in these patients following angioplasty. Prior to angioplasty, 19 scans showed redistribution. After successful coronary angioplasty in 18 of 19, 17 showed improvement in dipyridamole thallium scanning; one did not show improvement and later required repeat coronary dilatation. In one patient with failed angioplasty, images before and after angioplasty were unchanged. Nine scans showed "fixed" defects before angioplasty, with improvement in three of nine following angioplasty. Quantitative analysis of the dipyridamole thallium scans revealed significant improvement in uptake in the myocardial regions supplied by the successfully dilated artery (involved regions), but not in the remote (uninvolved) regions. We conclude that myocardial perfusion, as judged by dipyridamole thallium scanning, almost always improves following anatomically successful coronary angioplasty. "Fixed" defects may improve following angioplasty and presumably represent ischemia with incomplete redistribution, rather than infarction.

Adult↗

PubMed1994

Dipyridamole myocardial contrast echocardiography in patients with single-vessel coronary artery disease: perfusion, anatomic, and functional correlates.

The aim of this study was to examine whether myocardial contrast echocardiography (MCE) may be used to study regional myocardial blood flow distribution during dipyridamole-induced hyperemia. MCE was performed before and after dipyridamole infusion in 11 patients with a proximal, significant left anterior descending (LAD) coronary artery stenosis. The relation between contrast-derived parameters and the degree of coronary narrowing and the occurrence of transient regional wall motion abnormalities was also investigated. In the territory supplied by left circumflex coronary artery, mean peak contrast intensity increased after dipyridamole from 50 +/- 18 to 76 +/- 27 IU (p < 0.001). In contrast, a significant reduction in mean peak intensity was observed after dipyridamole in the LAD territory (from 41 +/- 27 to 13 +/- 13 IU, p < 0.01). Similar results were obtained with the use of the area under the time-intensity curve. An increase in peak intensity > or = 10 IU after dipyridamole administration separated normal regions from those supplied by a significant coronary artery lesion with a sensitivity of 91% and a specificity of 91%. Perfusion abnormalities were always detected by contrast echocardiography when septal motion abnormalities developed and, in five patients they were detected in the absence of clinical, electrocardiographic, and echocardiographic signs of ischemia. A weak correlation was found between both peak intensity and area under the curve and percent coronary diameter stenosis and cross-sectional area. In conclusion, dipyridamole MCE can be used during routine coronary angiography to assess myocardial blood flow distribution in patients with coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1995

Long-term risk stratification with dipyridamole imaging.

This study was undertaken to assess the reliability of clinical parameters and dipyridamole-thallium 201 images for predicting the occurrence of future cardiac events (nonfatal myocardial infarction or cardiac death). Dipyridamole myocardial perfusion imaging is routinely performed in patients who have possible or known coronary disease and a low exercise tolerance. A total of 753 patients underwent clinical assessment and semiquantitative dipyridamole-201TI imaging and were followed up as outpatients. Patients who underwent coronary revascularization during the follow-up period were excluded from the study because the decision to intervene would have been based at least in part on the test itself. There were 82 cardiac events and 54 noncardiac deaths, and 11 patients were lost to follow-up after a mean follow-up of 15 months. With use of a quantitative index reflecting the amount of jeopardized myocardium, patients could be stratified by dipyridamole imaging into subsets with coronary morbidity and mortality rates ranging from 1% to 89%, (p = 0.0001). When clinical and scintigraphic variables were subjected to backward stepwise logistic regression analysis, the significant predictors of cardiac events were the jeopardized myocardium index by scintigraphy (p < 0.0001), left ventricular hypertrophy on the electrocardiogram (p = 0.0009), and transient dipyridamole-induced left ventricular cavitary dilatation (p = 0.0073). Quantitative dipyridamole-201TI imaging appears to be a powerful predictor of future cardiac events in patients with coronary disease and a low exercise tolerance and is a potentially useful contributor to risk-profile assessment and to the treatment of these patients.

Aged↗

PubMed1986

Role of dipyridamole-echocardiography test in electrocardiographically silent effort myocardial ischemia.

A frequent clinical problem is documentation of the elusive entity of "electrocardiographically silent" effort myocardial ischemia. In this study, 83 patients with angina on effort and either negative or nondiagnostic exercise stress test results underwent a dipyridamole-echocardiography (echo) test, a feasible and useful tool for detection of coronary artery disease (CAD). The dipyridamole-echo test (2-dimensional echocardiographic monitoring combined with intravenous dipyridamole infusion at a maximal dosage of 0.84 mg/kg over 10 minutes) and coronary arteriography were performed in all patients. Positivity of dipyridamole-echo test was based on the detection of regional transient asynergy of contraction. At coronary arteriography, 50 of the 83 patients had significant (more than 70% diameter reduction) CAD: 27 had 1-vessel, 17 had 2-vessel and 6 had 3-vessel CAD. Interpretable echocardiograms were recorded in all the patients studied. The dipyridamole-echo test results were positive in 27 of the 50 patients (54%) with CAD. No patient without CAD had a positive test result. In conclusion, the dipyridamole-echo test frequently unmasks electrocardiographically silent effort myocardial ischemia by providing objective mechanical evidence of the ischemic event.

Adult↗