Background The outpatient prognostic assessment of coronary artery disease (CAD) by exercise electrocardiography has limitations, including the feasibility of the test and its low positive predictive value in several ...
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Background The outpatient prognostic assessment of coronary artery disease (CAD) by exercise electrocardiography has limitations, including the feasibility of the test and its low positive predictive value in several clinical conditions, In the current study we investigated the safety, feasibility, and prognostic value of pharmacologic stress echocardiography in a large cohort of ambulatory patients. Methods The study group was mode of 1482 ambulatory patients (969 men, aged 60 +/- 10 years) who underwent stress echocardiography with either dipyridamole (n = 846) or dobutamine (n = 636) for evaluation of suspected or known stable CAD. The pretest likelihood of CAD was intermediate (<70%) in 709 patients and high (70%) in 773 patients. Results There was no complication during the dipyridamole test, whereas 2 ischemia-dependent, sustained ventricular tachycardias occurred during the dobutamine test. Limiting side effects were observed in 2% of dipyridamole and in 3% of dobutamine stresses. The echocardiogram was positive in 459 patients. During a mean follow-up of 28 +/- 24 months, 58 patients died, 33 had a nonfatal myocardial infarction, and 158 underwent early (less than or equal to3 months) and 64 late (>3 months) revascularization. Multivariate predictors of hard events (death, infarction) were positive echocardiographic results (hazard ratio [HR] 2.9) and resting wall motion score index (WMSI) (HR 2.3). In considering major events (death, infarction, late revascularization) as end points, positive echocardiographic result (HR 4.3), scar (HR 2.2), and resting WMSI (HR 1.7) were independent prognostic predictors. The 5-year survivor rates for the ischemic and nonischemic groups were, respectively, 80% and 91% (HR 3.6, 95% confidence interval [CI] 3.8-8.4;P < .0001) considering hard cardiac events and 65% and 88% (HR 2.6, 95% Cl 2.1-5.9;P < .0001) considering major events. Multivariate predictors of major events were positive echocardiogra
Oxidized low-density lipoproteins are important in the progression of atherosclerosis. Autoantibodies against malondialdehyde-modified low-density lipoproteins have been reported to be predictive of the progression of...
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Oxidized low-density lipoproteins are important in the progression of atherosclerosis. Autoantibodies against malondialdehyde-modified low-density lipoproteins have been reported to be predictive of the progression of atherosclerosis. This study sought to examine whether plasma levels of autoantibodies against oxidized low-density lipoprotein increase in the coronary circulation in patients with coronary spastic angina. The authors examined plasma antioxidized low-density lipoprotein antibody levels (activity unit values (AcU)/mL) simultaneously in the coronary sinus and the aortic root in 20 patients with coronary spastic angina, 23 patients with stable exertional angina, and 15 control subjects by measuring plasma levels of immunoglobulin G (IgG) autoantibodies against malondialdehyde-modified low-density lipoproteins by enzyme-linked immunosorbent assay. The plasma antioxidized low-density lipoprotein antibody levels (AcU/mL) in the coronary sinus increased in coronary spastic angina (38 +/- 16) compared with stable exertional angina (23 +/- 7) and control subjects (20 +/- 6) (p less than or equal to 0.0001). The levels (AcU/mL) in the aortic root also increased in coronary spastic angina (33 +/- 12) compared with stable exertional angina (23 +/- 7) and control subjects (20 +/- 6) (p < 0.005). Furthermore, the coronary sinus-arterial differences of the levels (AcU/mL) were also higher in coronary spastic angina (5 9) than in stable exertional angina (0 +/- 6) and healthy subjects (-1 +/- 5) (p < 0.05). The generation of malondialdehyde-modified low-density lipoproteins is reported to be associated with atherothrombosis. These findings suggest that elevated levels of autoantibodies against malondialdehyde-modified oxidized low-density lipoproteins in coronary circulation are associated with the development of atherothrombosis from the progression of atherosclerosis rather than with the extent of coronary atherosclerosis in patients with coronary spast
Nine heart transplant recipients with cellular rejection were randomized to (1) treatment with low molecular weight heparin in addition to enhanced corticosteroids, or (2) enhanced corticosteroids alone. Compared with...
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Nine heart transplant recipients with cellular rejection were randomized to (1) treatment with low molecular weight heparin in addition to enhanced corticosteroids, or (2) enhanced corticosteroids alone. Compared with patients who received only enhanced corticosteroids, those who received low molecular weight heparin had a significant improvement in microvascular endothelial function.
This study evaluates the coronary flow reserve (CFR) in hypertensive patients with and without left ventricular (LV) hypertrophy. CFR was assessed by transesophageal Doppler echocardiography in 15 normal subjects (gro...
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This study evaluates the coronary flow reserve (CFR) in hypertensive patients with and without left ventricular (LV) hypertrophy. CFR was assessed by transesophageal Doppler echocardiography in 15 normal subjects (group I), 21 hypertensive patients without LV hypertrophy (group II), and 27 hypertensive patients with LV hypertrophy (group III). All hypertensive patients were complaining of typical anginal pain and had normal coronary angiograms. The sample volume was placed at the bifurcation of the left main and left anterior descending coronary arteries. Coronary blood flow velocities were evaluated at rest, 2 minutes after dipyridamole infusion, and 2 minutes after intravenous aminophylline. The ratios of dipyridamole to rest peak diastolic and systolic velocities were considered as indexes of CFR. Peak diastolic velocity ratio was significantly lower in group III than in groups I and II (1.6 +/- 0.2 2.7 +/- 0.4, and 2.1 +/- 0.2, respectively p <0.05), and it was significantly lower in group II then I (p <0.05). The peek systolic velocity ratio was significantly lower in group III than in groups I and II (1.7 +/- 0.3, 2.8 +/- 0.3, and 2.1 +/- 0.2, respectively;p <0.05), and it was significantly lower in group II than I (p <0.05). The peak diastolic velocity ratio was inversely related to systolic blood pressure, diastolic blood pressure, and LV mass index (r = -0.48, -0.51, and -0.37 respectively) in hypertensive patients. It is concluded that CFR is significantly impaired in hypertensive patients, especially those with LV hypertrophy, compared with healthy subjects. The degree of impairment of CFR is related to LV mass index. (C) 2000 by Excerpta Medica, Inc.
Background In patients taking digoxin, the exercise electrocardiogram has a lower specificity For detecting coronary artery disease. However, the effect of digoxin on adenosine-induced ST-segment depression is unknown...
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Background In patients taking digoxin, the exercise electrocardiogram has a lower specificity For detecting coronary artery disease. However, the effect of digoxin on adenosine-induced ST-segment depression is unknown. The purpose of this study was to evaluate the specificity of the electrocardiogram during adenosine myocardial perfusion imaging in patients taking digoxin. Methods Between May 1991 and September 1997, patients (n = 99) taking digoxin who underwent adenosine stress imaging with thallium-201 or technetium-99m sestamibi and coronary angiography within 3 months were retrospectively identified. Exclusion criteria included prior myocardial infarction, coronary artery angioplasty or bypass surgery, left bundle branch block, paced ventricular rhythm, or significant valvular disease. Twelve-lead electrocardiograms were visually interpreted at baseline, during adenosine infusion, and during the recovery period. The stress electrocardiogram was considered positive if there was greater than or equal to1 mm additional horizontal or downsloping ST-segment depression or elevation 0.08 seconds after the J-point compared with the baseline tracing. Results ST-segment depression and/or elevation occurred in 24 of 99 patients. There were only 2 false-positive stress electrocardiograms, yielding a specificity of 87% and positive predictive value of 92%. All 8 patients with greater than or equal to2 mm ST-segment depression had multivessel disease by coronary angiography. Conclusions ST-segment depression or elevation during adenosine myocardial perfusion imaging in patients taking digoxin is highly specific for coronary artery disease. Marked (greater than or equal to2 mm) ST-segment depression and/or ST-segment elevation is associated with a high likelihood of multivessel disease.
This study evaluated the role of adrenomedullin in patients with vasospastic nagina pectoris. Adrenomedullin may be involved in regulating a basal tone of the coronary artery in these patients.
This study evaluated the role of adrenomedullin in patients with vasospastic nagina pectoris. Adrenomedullin may be involved in regulating a basal tone of the coronary artery in these patients.
Background Patients with Marian syndrome show a hereditary abnormality of elastin metabolism that may cause aortic enlargement and dissection. We have hypothesized that abnormal elastin may alter peripheral vascular s...
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Background Patients with Marian syndrome show a hereditary abnormality of elastin metabolism that may cause aortic enlargement and dissection. We have hypothesized that abnormal elastin may alter peripheral vascular structure and function. Methods Forearm blood flow (FBF) (in milliliters per minute per 100 mL) response ta the endothelium-dependent dilator acetylcholine (0.75 to 4.5 mu g/min per 100 mt), the endothelium-independent dilator sodium nitroprusside (0.05 to 0.3 mu g/min per 100 mt), and structure-related maximum dilator response (10-minute occlusion-induced reactive hyperemia) were measured by plethysmograph in 10 patients with Marfan syndrome (mean age 44 years) and 10 healthy age- and sex-matched controls. Patients with the complications of hypercholesterolemia, diabetes mellitus, or heart Failure were excluded from the study. Results Basal FBF (mean +/- SE) did not differ between the 2 groups (2.7 +/- 0.3 vs 2.3 +/- 0.4). Maximum FBF response to acetylcholine in patients with Marfan syndrome was significantly lower than that of healthy controls (8.5 +/- 2.1 vs 15.4 +/- 1.7 mL/min per 100 mi;P < .05). Reactive hyperemia was also lower in patients with Marfan syndrome (at peak 23.0 +/- 2.5 vs 29.5 +/- 2.3 mL/min per 100 mt;P < .05), but sodium nitroprusside-induced FBF changes did not differ between the 2 groups (10.3 +/- 1.1 vs 10.2 +/- 1.5 mL/min per 100 mt;P = not significant). Conclusion These observations suggest that endothelium-dependent dilation and maximum dilator reserve capacity are both abnormal in peripheral resistance vessels of patients with Marfan syndrome. These peripheral vasomotion abnormalities may have a detrimental impact on the cardiovascular system in this disorder.
Several studies have been undertaken using myocardial perfusion imaging to detect myocardial ischemia in patients with mitral valve prolapse (MVP).1–9 Controversial results were obtained in patients with MVP without ...
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Several studies have been undertaken using myocardial perfusion imaging to detect myocardial ischemia in patients with mitral valve prolapse (MVP).1–9 Controversial results were obtained in patients with MVP without coronary artery disease.1–11 Moreover, these previous studies have been performed mostly in the 1970s using planar myocardial perfusion imaging with thallium-201 (Tl-201).1–8 Recently, it was shown that single-photon emission computed tomography has better ability to allow visual analysis of all coronary regions in the diagnosis of coronary artery disease than planar imaging.12–14 This study was designed to assess myocardial perfusion imaging using single-photon emission computed tomographic (SPECT) analysis and recently established echocardiographic criteria for MVP.
The aim of our study was to compare the prognostic value of stress echocardiography and exercise electrocardiography after uncomplicated non-Q-wave acute myocardial infarction in a series of 89 female patients. Our da...
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The aim of our study was to compare the prognostic value of stress echocardiography and exercise electrocardiography after uncomplicated non-Q-wave acute myocardial infarction in a series of 89 female patients. Our data show that stress echocardiography has independent predictive value in a female patient population recovering from uncomplicated acute myocardial infarction.
Despite the widespread use of head-up tilt testing as a means for diagnosing vasovagal syncope, standardization of test methodology remains a controversial issue. The aim of this study was to compare the diagnostic va...
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Despite the widespread use of head-up tilt testing as a means for diagnosing vasovagal syncope, standardization of test methodology remains a controversial issue. The aim of this study was to compare the diagnostic value of head-up tilt testing potentiated with sublingual nitroglycerin with that of head-vp tilt testing potentiated with law-dose isoproterenol. For this purpose, 71 patients with unexplained syncope (mean age 43 years) and 30 asymptomatic controls were studied. All underwent the sublingual nitroglycerin and low-dose isoproterenol tests on separate days in a randomized fashion. The protocol of the 2 tests was similar and consisted of 2 phases. Initially, subjects were tilted at 60 degrees for 20 minutes without medication;then, if syncope did not occur, patients and controls received sublingual nitroglycerin (300 mu g) or low-dose intravenous isoproterenol (mean infusion rate 1.3 +/- 0.5 mu g/min) and continued to be tilted at 60 degrees for a further 20 minutes. During the sublingual nitroglycerin test, a positive response (syncope associated with sudden hypotension and bradycardia) occurred in 35 patients (49%), a negative response in 36 (51%), and drug intolerance in none (0%). During the low-dose isoproterenol test, these percentages were 41%, 59%, and 6%, respectively. A concordant response was observed in 53 cases (75%). Among controls, 3 subjects (10%) had a positive response to the sublingual nitroglycerin test and 4 (13%) to the low-dose isoproterenol test. It is concluded that sublingual nitroglycerin and low-dose isoproterenol are equivalent tests for evaluating patients with unexplained syncope. The sublingual nitroglycerin test, however, is simpler, better tolerated, and safer than the low-dose isoproterenol test and, thus, more suitable for routine clinical use. (C) 2000 by Excerpta Medica, Inc.
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