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PubMedDate not supplied

Detection of coronary artery disease: comparison between technetium 99m-labeled sestamibi single-photon emission computed tomography and two-dimensional echocardiography with dipyridamole low-level exercise-stress.

BACKGROUND: Myocardial perfusion imaging in conjunction with dipyridamole low-level exercise stress has proved its value in the evaluation of patients with coronary artery disease (CAD). Simultaneous wall motion analysis by two-dimensional (2D) echocardiography may provide additional information beyond that obtained by myocardial perfusion imaging alone. The purpose of this study was to compare 99mTc-labeled sestamibi single-photon emission computed tomography (SPECT) and 2D echocardiography for the evaluation of CAD according to a dipyridamole low-level bicycle exercise stress protocol. METHODS AND RESULTS: We studied 35 consecutive patients referred for the evaluation of chest pain who had undergone coronary arteriography. 99mTc-labeled sestamibi SPECT and 2D echocardiography agreed in 27 patients (80%) studied for overall detection of CAD. On a segmental basis, agreement was found between SPECT and 2D echocardiography in 124 (73%) of 170 segments (Cohen's kappa = 0.43). The accuracy of the combined assessment of myocardial perfusion and echocardiographic wall motion in detecting CAD was 86%, which was not different from the accuracy of SPECT alone (80%; difference not significant) but significantly higher than for 2D echocardiography alone (71%; p = 0.03). In the detection of individual coronary artery stenoses, SPECT had a significantly higher accuracy for detecting left anterior descending coronary artery lesions than had 2D echocardiography (80% vs 60%; p < 0.01); combining the two method did not improve the accuracy (80%). The combined assessment slightly improved the accuracy for detecting left circumflex coronary artery stenoses from 71% to 83% (p = 0.05). CONCLUSION: The combined simultaneous assessment of myocardial perfusion by 99mTc-labeled sestamibi SPECT and wall motion by 2D echocardiography did not significantly improve overall accuracy over that obtained by 99mTc-labeled sestamibi SPECT alone. Therefore 99mTc-labeled sestamibi SPECT with dipyridamole low-level exercise stress appears the preferred imaging modality for the evaluation of patients with CAD.

Adult↗
PubMed1997

Detection of patients with restenosis after PTCA by dipyridamole-atropine-stress-echocardiography.

Stress-echocardiography (SE) has been proven to be a valuable method for the diagnosis of coronary artery disease. For patients who cannot exercise, pharmacological stress-echocardiography represents an alternative method for the induction of cardiovascular stress. Few studies exist concerning the value of dipyridamole-SE for the detection of restenosis in patients after primary successful PTCA. It has been demonstrated that the addition of atropine can significantly increase the diagnostic potential of dipyridamole-SE, especially in patients with 1- or 2-vessel disease. The purpose of our study was to investigate the diagnostic value of high-dose dipyridamole-SE plus atropine (DASE) for the detection of restenosis after primary successful PTCA. We investigated 65 patients 3-6 months after PTCA before a control angiography was performed. Restenosis was defined as > 70% lumen narrowing, determined by quantitative coronary angiography. In 20/27 patients with restenosis, the DASE was pathological (sensitivity 74%); in 34/38 patients without restenosis the DASE was normal or showed no induced WMA (specificity 89%). Patients with tight restenosis (> 90%) were always correctly detected by DASE. Concerning the different vessels, restenosis of the LAD was correctly predicted by DASE in 11/12 patients, restenosis of the LCX in 6/9 patients and restenosis of the RCA in 8/11 patients. From the results of our study we conclude that DASE is a reliable diagnostic method for the non-invasive evaluation of patients after PTCA. DASE can identify patients with relevant restenosis after PTCA and help to select those patients who will probably benefit from further coronary interventions, for repeat angiography.

Angioplasty, Balloon, Coronary↗
PubMed2001

Free radical oxidation and antioxidant activity in blood plasma and myocardium during long-term dipyridamole treatment.

Activation of free radical oxidation and inhibition of antioxidant activity in mouse myocardium after long-term dipyridamole treatment were demonstrated using chemiluminescent techniques. At the same time, dipyridamole 10-fold inhibited free radical oxidation and slightly increased antioxidant activity in the plasma. Dipyridamole-induced platelet disaggregation was accompanied by an increase in platelet count.

Animals↗
PubMed2001

Effect of disturbed plasma oxidant homeostasis on hemopoietic differentiation of polypotent bone marrow stem cells in mice treated with dipyridamole.

The choice of hemopoietic differentiation by polypotent bone marrow stem cells was studied by morphological and chemiluminescent methods. This choice occurred on day 7 after heterotopic bone marrow transplantation and dipyridamole administration, under the effect of oxidative homeostasis imbalance in the plasma. Dipyridamole increased total antioxidant activity and 10-fold reduced the intensity of free radical oxidation. Disaggregation therapy with dipyridamole reduced platelet count in the peripheral blood and decreased total plasma antioxidant activity.

Animals↗
PubMed2003

Head-to-head comparison of dipyridamole echocardiography and stress perfusion scintigraphy for the detection of coronary artery disease: a meta-analysis. Comparison between stress echo and scintigraphy.

OBJECTIVES: This meta-analysis was performed to assess and compare the diagnostic accuracy of dipyridamole echocardiography test (DET) vs. stress perfusion scintigraphy (SPS) for the diagnosis of coronary artery disease (CAD). METHODS: We performed a meta-analysis of peer reviewed articles, published in English language reporting head-to-head comparison of DET vs. SPS for the diagnosis of CAD. Data of 10 studies comprising 651 patients from 10 different institutions were analyzed. DET dose was 0.56 mg/kg (low dose) in two studies, 0.75 mg/kg in 10 min or 0.84 mg/kg in 10 min (high dose) in six studies, and 0.84 mg/kg in 6 min (accelerated high dose) in one study and 0.84 mg/kg in 10 min + 1 mg atropine co-administration (augmented dose) in one study. SPS was performed with dipyridamole in six studies, with exercise in three studies and with dobutamine in one study. RESULTS: The overall diagnostic accuracy of the two tests was almost similar, 77% (95% CI = 74-81) for DET vs. 81% (95% CI = 78-84) for SPS (p = ns). SPS gave higher sensitivity, 88% (95% CI = 85-89) than DET, 70% (95% CI = 66-75) in cumulative data (p < 0.0001) while DET gave higher specificity, 90% (95% CI = 86-94) vs. 67% (95% CI = 60-73) (p < 0.0001). With state of the art protocols, i.e. accelerated dose and atropine augmented high dose, sensitivity of DET improved and overall accuracy was better than SPS (p < 0.05). CONCLUSION: DET and SPS have a similar diagnostic accuracy. DET has a markedly higher specificity regardless of the dose employed. SPS shows a superior sensitivity, however this sensitivity gap diminishes when more aggressive dipyridamole dosage is used for the stress echocardiography.

Coronary Disease↗
PubMed1986

How does dipyridamole elevate extracellular adenosine concentration? Predictions from a three-compartment model of adenosine formation and inactivation.

Steady-state mathematical models are developed according to which adenosine is formed in the cytoplasm of a group of cells, arises in the extracellular space via the symmetric nucleoside transporter and is inactivated in the adenosine forming cells and after rate-limiting transport into other cell-types. Dipyridamole increases the Km and Vmax. of the transporter symmetrically with respect to influx and efflux. Models incorporating differing degrees of compartmentation are used to predict intracellular and extracellular adenosine concentration as a function of dipyridamole concentration and adenosine formation rate. The vasodilator action of dipyridamole is explained since it is predicted to elevate interstitial fluid adenosine concentrations at all rates of adenosine formation provided that washout of the interstitial compartment is restricted.

Adenosine↗
PubMed1998

Diagnostic accuracy and prognostic value of combined dipyridamole-exercise thallium imaging in hemodialysis patients.

BACKGROUND: Non-invasive detection of coronary artery disease in dialysis patients, a major cause of mortality, often remains difficult. The aim of the study was to test the diagnostic and prognostic accuracies of combined dipyridamole-exercise thallium imaging in dialysis patients. METHODS: Dipyridamole-exercise thallium imaging and coronary angiography were both performed prospectively in 60 asymptomatic hemodialysis patients who were followed up, long term, by recording any major coronary event. RESULTS: Coronary angiography was abnormal in 13 patients (21%), and there was abnormal thallium uptake in 17 patients. Sensitivity, specificity, positive and negative predictive values, and overall accuracy of thallium to detect a coronary artery disease were 92, 89, 71, 98 and 90%, respectively. After a median follow-up of 2.8 years, 12 patients experienced at least one major coronary event (4 cardiac deaths, 5 myocardial infarctions and 3 revascularizations). Eight of the 17 patients with abnormal thallium uptake (47%) suffered a coronary event, compared to only 4 of the 43 patients (9%) with a normal thallium uptake (P < 0.001). The positive prognostic predictive value of thallium imaging was 47% and its negative predictive value was 91%. The probability of survival free of coronary events was significantly higher in patients with normal thallium uptake than in those with abnormal thallium uptake (crude risk ratio 7.6; P < 0.001) even after adjustment for several risk factors for cardiovascular disease (adjusted risk ratio 9.2; P < 0.005). CONCLUSION: In dialysis patients, combined dipyridamole-exercise thallium imaging is an accurate method for detecting coronary stenosis and for predicting future coronary events.

Adult↗
PubMed1998

Dipyridamole stress thallium-201 perfusion abnormalities in patients with hypertrophic cardiomyopathy. Relationship to clinical presentation and outcome.

AIMS: Thallium-201 perfusion abnormalities are common in patients with hypertrophic cardiomyopathy and may be associated with an adverse prognosis in the young. The aim of this study was to prospectively determine the relationship between thallium-201 defects during dipyridamole stress to clinical presentation and outcome in a large consecutive series of patients with hypertrophic cardiomyopathy. METHODS/RESULTS: Thallium-201 single photon computed tomography was performed in 216 patients with hypertrophic cardiomyopathy during dipyridamole stress (0.5 mg. kg-1). Fixed perfusion defects occurred in 25%, and reversible defects in 22%. A combination of defects was present in 7%. Fixed defects were associated with: a history of syncope (17 of 46 with, vs 36 of 170 without syncope, P = 0.03); larger left ventricular end-diastolic (46.9 +/- 7.4 mm vs 43.3 +/- 6.4 mm; P = 0.001) and end-systolic dimension (30.2 +/- 8.4 mm vs 24.5 +/- 5.9 mm, P < 0.0001); increased left atrial diameter (46.1 +/- 8.1 mm vs 40.5 +/- 7.7 mm, P < 0.0001); lower fractional shortening (35.9 +/- 10.4% vs 43.8 +/- 8.6%, P < 0.0001): and lower maximal exercise oxygen consumption (24.2 +/- 8.1 ml. min-1. kg-1 vs 29.4 +/- 8.8 ml. min-1. kg-1, P < 0.0003). Reversible defects did not correlate with symptomatic status, but were associated with: larger left atrial dimensions (44.5 +/- 8.1 mm vs 41.0 +/- 8.0 mm; P = 0.009) and greater maximal left ventricular wall thickness (24.0 +/- 7.0 mm vs 20.6 +/- 7.0 mm, P = 0.003). The mean follow up time was 41 +/- 21 months, range 0.6-124. There was no association between any thallium-201 abnormality and disease related death in young or adult patients. CONCLUSION: The present study shows that fixed thallium-201 perfusion defects detected during dipyridamole stress in patients with hypertrophic cardiomyopathy are associated with syncope, larger left ventricular cavity dimensions and reduced exercise capacity. Although the event rate was relatively small, there was no evidence for an association between thallium-201 defects and survival.

Adolescent↗
PubMed1999

Effect of dipyridamole on prostanoid production in rat isolated atria.

The effect of 0.01 microM dipyridamole on prostanoid production was studied in atria from normal, acute diabetic and insulin-treated diabetic rats. Diabetes was induced by i.v. administration of 65 mg/kg of streptozotocin (STZ) and the rats were killed 5 days later. Atria were incubated during 60 min in Krebs solution. The prostanoids 6-keto-prostaglandin (PG) F1alpha (6-keto-PGF1alpha) and thromboxane (TX) B2, stable metabolites of prostacyclin and TXA2, respectively, as well as PGE2 were measured by reversed phase high-performance liquid chromatography-UV. In diabetic atria, 6-keto-PGF1alpha production was reduced by 50% whereas TXB2 release was increased two-fold compared to the controls, with a significant decrease in the 6-keto-PGF1alpha/TXB2 ratio. The preincubation with 0.01 microM dipyridamole for 30 min increased 6-keto-PGF1alpha production in control, diabetic and insulin-treated diabetic atria whereas TXB2 release was not modified. This effects provoked an significant increase in the 6-keto-PGF1alpha/TXB2 ratio. In conclusion, STZ diabetes reduces the 6-keto-PGF1alpha/TXB2 ratio impairing the functional status of the atria. Dipyridamole increased this ratio in atria from diabetic and insulin-treated diabetic rats, thus opposing the effects of STZ diabetes. This fact suggests the possibility of a participation of the drug in pathologies characterized by an imbalance in the production of vasodilator and vasoconstrictor prostanoids.

6-Ketoprostaglandin F1 alpha↗
PubMed1984

Effect of dipyridamole and aspirin on late vein-graft patency after coronary bypass operations.

To study the prevention of occlusion of aortocoronary-artery bypass grafts, we concluded a prospective, randomized, double-blind trial comparing long-term administration of dipyridamole (begun two days before operation) plus aspirin (begun seven hours after operation) with placebo in 407 patients. Results at one month showed a reduction in the rate of graft occlusion in patients receiving dipyridamole and aspirin. At vein-graft angiography performed in 343 patients (84 per cent) 11 to 18 months (median, 12 months) after operation, 11 per cent of 478 vein-graft distal anastomoses were occluded in the treated group, and 25 per cent of 486 were occluded in the placebo group. The proportion of patients with one or more distal anastomoses occluded was 22 per cent of 171 patients in the treated group and 47 per cent of 172 in the placebo group. All grafts were patent within a month of operation in 94 patients in the placebo group and 116 patients in the treated group; late development of occlusions was reduced from 27 per cent in the placebo group to 16 per cent in the treatment group. The results show that dipyridamole and aspirin continue to be effective in preventing vein-graft occlusion late after operation, and we believe that such treatment should be continued for at least one year.

Adult↗
PubMed1988

Aspirin and dipyridamole in the prevention of restenosis after percutaneous transluminal coronary angioplasty.

To examine the role of antiplatelet therapy in the prevention of arterial restenosis after percutaneous transluminal coronary angioplasty (PTCA), we conducted a randomized, double-blind, placebo-controlled study in 376 patients. The active treatment consisted of an oral aspirin-dipyridamole combination (330 mg-75 mg) given three times daily, beginning 24 hours before PTCA. Eight hours before PTCA, the oral dipyridamole was replaced with intravenous dipyridamole at a dosage of 10 mg per hour for 24 hours, and oral aspirin was continued. Sixteen hours after PTCA, the initial combination was reinstituted. Treatment was continued in patients with a successfully dilated vessel until follow-up angiography four to seven months after PTCA--or earlier, if symptoms dictated. Of 249 patients who underwent follow-up angiography, 37.7 percent of patients receiving the active drug had restenosis in at least one segment, as compared with 38.6 percent of patients taking placebo (P not significant). The number of stenotic segments was virtually the same in the two groups. Among the 376 randomized patients, there were 16 periprocedural Q-wave myocardial infarctions--13 in the placebo group and 3 in the active-drug group (6.9 percent vs. 1.6 percent, P = 0.0113). Although the use of this antiplatelet regimen before and after PTCA did not reduce the six-month rate of restenosis after successful coronary angioplasty, it markedly reduced the incidence of transmural myocardial infarction during or soon after PTCA. Thus, the short-term use of antiplatelet agents in relation to PTCA can be recommended.

Administration, Oral↗
PubMed1994

Dipyridamole-thallium scintigraphy and gated radionuclide angiography to assess cardiac risk before abdominal aortic surgery.

BACKGROUND: Because many patients with atherosclerotic disease of the abdominal aorta also have coronary artery disease, assessment of cardiac risk before abdominal aortic surgery has received much attention. Our prospective study was designed to identify predictors of cardiac risk in consecutive patients evaluated preoperatively with dipyridamole-thallium single-photon-emission computed tomography (SPECT) to assess myocardial perfusion and radionuclide angiography to measure left ventricular ejection fraction. METHODS: Clinical and scintigraphic data were collected prospectively during hospitalization in 457 consecutive patients undergoing elective abdominal aortic surgery. Adverse cardiac outcomes were predicted with multivariate analyses. RESULTS: Eighty-six patients (19 percent) had one or more of the following postoperative complications: prolonged myocardial ischemia (61 patients), myocardial infarction (22), congestive heart failure (20), and severe ventricular tachyarrhythmia (2). Twenty patients died postoperatively (4.4 percent), half of them from cardiac causes. Information about myocardial perfusion obtained from dipyridamole-thallium SPECT did not accurately predict adverse cardiac outcomes. The best correlates of cardiac complications were definite clinical evidence of coronary artery disease (odds ratio, 2.6; 95 percent confidence interval, 1.6 to 4.3) and age greater than 65 years (odds ratio, 2.3; 95 percent confidence interval, 1.4 to 3.6). Measurement of the ejection fraction was useful only in the prediction of left ventricular failure. Age greater than 65 years was the only predictor of death (odds ratio, 26.4; 95 percent confidence interval, 3.5 to 200.0). CONCLUSIONS: The presence of definite clinical evidence of coronary artery disease and older age were the most important preoperative predictors of an adverse cardiac outcome after abdominal aortic surgery. These results suggest that the routine use of dipyridamole-thallium SPECT and radionuclide angiography for screening before abdominal aortic surgery may not be justified.

Aged↗
PubMed2002

Diadenosine pentaphosphate vasodilates the forearm vascular bed: inhibition by theophylline and augmentation by dipyridamole.

BACKGROUND: In rats, diadenosine pentaphosphate (AP(5)A) has been implicated in the pathogenesis of essential hypertension. This study describes for the first time the vasomotor action of AP(5)A in humans by means of the "perfused forearm technique." RESULTS: AP(5)A evoked a dose-dependent forearm vasodilator response equal to that of adenosine but less than that of adenosine triphosphate (ATP) at equimolar doses. The P(1)-purinoceptor antagonist theophylline (0.28 micromol/min per deciliter) reduced the percentage decrease in forearm vascular resistance (FVR) to AP(5)A (0.6, 6, and 20 nmol/min/dL): -8% +/- 6%, -50% +/- 6%, and -68% +/- 4% during saline solution versus -7% +/- 4%, -33% +/- 5%, and -45% +/- 6% during theophylline (mean +/- standard error [SE]; ANOVA for repeated measures; P <.05 for the interaction between purine dose and theophylline; n = 10). An inhibitor of equilibrative nucleoside transport, dipyridamole (7.4 nmol/min per deciliter), augmented the AP(5)A (0.6 and 6 nmol/min per deciliter)-induced reduction in FVR as follows: -34% +/- 6% and -67% +/- 5% during saline versus -49% +/- 5% and -80% +/- 3% during dipyridamole (P <.05 for the effect of dipyridamole; n = 6). The bivalent cation chelator ethylenediaminetetra-acetic acid (EDTA) inhibited the rapid degradation of AP(5)A in vitro. In vivo, the highest tolerated intra-arterial EDTA dose was not sufficient to inhibit AP(5)A metabolism. CONCLUSION: Intra-arterial AP(5)A caused a dose-dependent reduction in FVR. This is, at least in part, mediated by its degradation product adenosine. The data do not support an in vivo vasoconstrictor action of AP(5)A, and as such AP(5)A does not seem likely to contribute to the pathogenesis of primary hypertension in humans.

Adult↗
PubMed2001

Dipyridamole stress ultrasonic myocardial tissue characterization in patients with Kawasaki disease.

Dipyridamole stress integrated backscatter (IBS) was used for evaluation of myocardial ischemia or damage in 31 children with coronary artery lesions caused by Kawasaki disease, in comparison with thallium-201 myocardial imaging. All patients underwent echocardiography at rest and after dipyridamole stress at the anterior interventricular septum, posterior wall (PW), and inferior wall (INF). At rest, no significant difference was seen in cyclic variation (CV) of IBS in the regions with normal or abnormal distribution on Tl-201 imaging. But in the regions showing abnormal distribution after stress, CV decreased significantly. A delayed study after stress showed the recovery of CV to the level at rest in all patients. Sensitivity of abnormal cyclic variation integrated backscatter was 75% in the PW and 91% in the INF, and specificity was 91% in the PW and 90% in the INF, compared with the results of thallium-201 imaging. Dipyridamole stress IBS can provide sensitive detection of myocardial ischemia or damage in Kawasaki disease.

Adolescent↗
PubMedDate not supplied

Comparison of pulmonary uptake with transient cavity dilation after dipyridamole Tl-201 perfusion imaging.

BACKGROUND: Elevated lung-heart ratio (LHR) and transient ischemic dilation (TID) have been identified as markers of severe coronary artery disease after both exercise and pharmacologic stress testing. We have previously demonstrated a very weak correlation between elevated LHR and TID after exercise, which suggests that they reflect different pathophysiologic manifestations of coronary disease. Because the physiology of pharmacologic vasodilation with dipyridamole is significantly different than that of physical exercise, we undertook this study to evaluate the relationship between elevated LHR and TID after pharmacologic stress testing with dipyridamole. METHODS AND RESULTS: We identified 1129 consecutive patients who underwent pharmacologic stress imaging with dipyridamole and thallium 201. LHR and a dilation index were calculated and compared with each other and with relevant clinical parameters. Echocardiographic parameters were also compared in a subset of 475 patients who had echocardiography within 2 weeks of pharmacologic stress testing. There was no significant correlation between elevated LHR and TID despite the fact that both were associated with more severe thallium stress and redistribution scores. Patients with elevated LHR were more likely to have a history of myocardial infarction and coronary artery bypass grafting and to have lower ejection fraction. Patients with TID were more likely to have a positive electrocardiographic response (15% vs 7%, P =.0003), which was not seen in patients with elevated LHR (11% vs 8%, P =.23). CONCLUSIONS: Although both elevated LHR and TID were associated with more severe coronary disease, they have no significant correlation. Patients with elevated LHR are more likely to have a history of myocardial infarction or coronary artery bypass grafting, a larger left ventricle, and lower ejection fraction. Our results support the hypothesis that TID is due to diffuse subendocardial hypoperfusion and represents a different pathophysiologic response to ischemia than elevated LHR.

Aged↗
PubMed2004

Platelet activation markers, microparticles and soluble adhesion molecules are elevated in patients with arteriosclerosis obliterans: therapeutic effects by cilostazol and potentiation by dipyridamole.

We evaluated the plasma concentrations of platelet activation markers, microparticles and soluble adhesion molecules in patients with arteriosclerosis obliterans (ASO) and compared the beneficial effects of cilostazol alone and combination therapy of cilostazol and dipyridamole in these patients. There was a significant elevation of CD62P, CD63, PAC-1, annexin V, platelet-derived microparticles (PDMPs), sP-selectin, sE-selectin, sICAM-1 and sVCAM-1 in the ASO patients compared with the controls. Platelet aggregation was decreased by 2 weeks of cilostazol monotherapy in the ASO patients. Adding dipyridamole to the cilostazol therapy for 2 weeks further reduced platelet aggregation. While treatment with cilostazol alone reduced levels of CD62P, CD63, PAC-1, annexin V, PDMP, and sP-selectin, the combination therapy reduced these parameters further. While sE-selectin and cell adhesion molecules did not change significantly after 2 weeks of combination therapy, they exhibited a remarkable decrease after 16 weeks of combination treatment. These findings suggest that platelets are activated in ASO patients, and cilostazol is effective to reduce platelet activation. Furthermore, dipyridamole may potentiate the beneficial effect of cilostazol in ASO patients. Combination use of both drugs may help to prevent the onset of cardiovascular complications in patients with ASO by activated platelets and PDMP.

Aged↗
PubMedDate not supplied

In vitro antioxidant and photo-oxidant properties of dipyridamole.

The in vitro antioxidant and photo-oxidant activity of dipyridamole was studied by its effect on superoxide- and singlet oxygen-mediated photohemolysis and viability of neutrophils. Dipyridamole was found to be phototoxic when examined by the photohemolysis on human erythrocytes and on linoleic acid as lipid peroxidation model at concentrations above 3.0 x 10(-5) M. On the contrary, when lower concentrations (1.0 x 10(-5) to 1.0 x 10(-6) M) were used, dipyridamole showed a protector action against singlet oxygen-mediated photohemolysis by other phototoxic compounds like triamterene. This antioxidant property is proposed to result from quenching of triamterene mediated by fluorescence energy transfer. Auto-oxidation and fluorescence-energy transfer is clearly an important mechanism for protection for this drug.

Antioxidants↗
PubMed1989

Dipyridamole-echocardiography test in essential hypertensives with chest pain and angiographically normal coronary arteries.

Microvascular angina--chest pain syndrome in the presence of angiographically normal epicardial coronary arteries and reduced flow reserve--has been described in patients with essential hypertension (EH) and linked to the development of left ventricular hypertrophy (LVH). We performed a dipyridamole-echocardiography test (DET: 2D-echo and 12 lead ECG monitoring with dipyridamole infusion, up to 0.84 mg/kg over ten minutes) in 28 essential hypertensives meeting the following inclusion criteria: (1) history of chest pain; (2) angiographically normal coronary arteries; (3) normal resting regional and global left ventricular function. A group of 12 (age- and sex-matched) normotensives with the same inclusion criteria, as well as with negative exercise stress test, was also evaluated. During DET, none of the essential hypertensives or the control group developed a regional dyssynergy of contraction. Fifteen essential hypertensives and two in the control group had a diagnostic (greater than 0.1 mV from baseline) ST segment depression on ECG tracing (54 v 17%, P less than .01); 16 essential hypertensives and two in the control group had chest pain (57 v 17%, P less than .01). None of the control group and nine of the essential hypertensives had echocardiographically assessed LVH. In the essential hypertensive group ventricular hypertrophy was present in seven of 20 patients with and in two of eight patients without dipyridamole induced chest pain and/or ST segment depression (35% v 25%, P = NS). In conclusion, essential hypertensive patients with chest pain and angiographically normal coronary arteries frequently show echocardiographically silent angina and/or ST segment depression during DET.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗