BACKGROUND: The rising costs of healthcare have forced policy makers to make choices, and new treatments are increasingly assessed in terms of the balance between additional costs and additional effects. The recent recognition that... more
BACKGROUND: The rising costs of healthcare have forced policy makers to make choices, and new treatments are increasingly assessed in terms of the balance between additional costs and additional effects. The recent recognition that stenting has a major and long-lasting effect enhancing balloon PTCA procedure has made it imperative to compare in patients with multivessel disease the standard surgical procedure with multiple stenting in a large-scale multinational and multicenter approach (19 countries, 68 sites). METHODS: Selection and inclusion of patients is based on a consensus of the cardiac surgeon and interventional cardiologist on equal 'treatability' of patients by both techniques with analysis of clinical follow-up (event-free survival) on the short (30 days), medium (1 year), and long term (3 and 5 years) with analysis of cost-effectiveness and quality of life (EuroQol and SF-36). Of the entire trial, the primary null hypothesis which needs to be rejected is that there will be no difference in event-free survival or effectiveness (E), at 1 year and also that the direct and indirect costs (C) per event-free year are not different between surgery or stenting. For this to become significant with a power of 90% requires 1200 patients. Between April 97 and June 98, 1205 patients have been randomized with a monthly recruitment of 83 patients; the one year follow-up will thus be completed in June 1999. Expected costs, effects and cost-effectiveness ratio (CE ratio) for stents are: Stent: high-cost estimate, 2 vessel disease (C 3 $19,297, E 3 81%, CE ratio 3 $23,876); 3 vessel disease (C 3 $24,566, E 3 81%, CE ratio 3 $30,397) low-cost estimate, 2 vessel disease (C 3 $16,638, E 3 81%, CE ratio 3 $20,586); 3 vessel disease (C 3 $20,456, E 3 81%, CE ratio 3 $25,322) Compared with CABG (C 3 $21,350, E 3 88%, CE ratio 3 $24,348) CONCLUSION: Clinically, stenting is not expected to be more effective than CABG, but should be cost-effective in both the 2- and 3-vessel disease groups when using the lower-cost estimate and in the 2 vessel group when using the higher-cost assumptions. (Int J Cardiovasc
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ABSTRACT The angiotensin converting enzyme (ACE) inhibitors constitute a major breakthrough in the medical management of congestive heart failure. The incidence of side effects with these agents is surprisingly low when they are used in... more
ABSTRACT The angiotensin converting enzyme (ACE) inhibitors constitute a major breakthrough in the medical management of congestive heart failure. The incidence of side effects with these agents is surprisingly low when they are used in the appropriate dosage. They produce sustained beneficial hemodynamic and symptomatic improvement in most patients with congestive heart failure and may produce greater symptomatic benefit than digoxin when given as second-line therapy to patients with heart failure on diuretics. Their neurohumoral effects generally are advantageous, resulting in normalization of sodium and potassium balance and a reduction in ventricular arrhythmias. The ACE inhibitors may improve survival in patients with congestive heart failure, and recent data suggest that they may prevent or delay the development of left ventricular dilatation and overt heart failure in patients with asymptomatic left ventricular dysfunction
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The angiotensin converting enzyme (ACE) inhibitors constitute a major breakthrough in the medical management of congestive heart failure. The incidence of side effects with these agents is surprisingly low when they are used in the... more
The angiotensin converting enzyme (ACE) inhibitors constitute a major breakthrough in the medical management of congestive heart failure. The incidence of side effects with these agents is surprisingly low when they are used in the appropriate dosage. They produce sustained beneficial hemodynamic and symptomatic improvement in most patients with congestive heart failure and may produce greater symptomatic benefit than digoxin when given as second-line therapy to patients with heart failure on diuretics. Their neurohumoral effects generally are advantageous, resulting in normalization of sodium and potassium balance and a reduction in ventricular arrhythmias. The ACE inhibitors may improve survival in patients with congestive heart failure, and recent data suggest that they may prevent or delay the development of left ventricular dilatation and overt heart failure in patients with asymptomatic left ventricular dysfunction.
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Research Interests: Cardiology, Adolescent, Medicine, Pulmonary Hypertension, Humans, and 15 moreInternal Medicine, Hemodynamics, Blood Pressure, Female, Male, Heart rate, Middle Aged, Adult, Nifedipine, Aorta, Vascular Resistance, Prostacyclin, Cardiac output, Medical and Health Sciences, and Cardiovascular medicine and haematology
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One of the basic caveats in endocrinology is that glandular abnormalities tend to occur together. Continued suspicion of other glandular hypofunction should be maintained in following patients with any type of endocrine gland... more
One of the basic caveats in endocrinology is that glandular abnormalities tend to occur together. Continued suspicion of other glandular hypofunction should be maintained in following patients with any type of endocrine gland hypofunction, since the risk of multiple glandular involvement is significant. Family members should be alerted to the high prevalence of endocrinopathies especially among first-degree relatives of patients with polyglandular autoimmune disease. Parameters such as antiorgan antibodies, although occasionally helpful, have not been shown to be consistently useful in predicting the future development of clinical organ-specific autoimmune disease. HLA typing remains a research tool at this time, as does evaluation of humoral and cell-mediated immunity.
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The beneficial effects of acute prazosin therapy in patients with congestive heart failure (CHF) have been well documented; however, its chronic efficacy over several months has not previously been evaluated in a placebo-controlled... more
The beneficial effects of acute prazosin therapy in patients with congestive heart failure (CHF) have been well documented; however, its chronic efficacy over several months has not previously been evaluated in a placebo-controlled manner. Therefore, an assessment was made by radionuclide ventriculography of the effect of prazosin, 20 mg/day, on left ventricular ejection fraction and end-systolic and end-diastolic volumes at rest and on peak upright bicycle exercise, as well as its effect on right ventricular ejection fraction at rest, exercise time and work load, and standard clinical variables in 23 patients with stable class III symptoms of CHF. The study consisted of a 6-month randomized, double-blind, controlled evaluation of prazosin versus placebo in patients receiving a stable dose of digitalis and diuretics for at least 1 month. At entry, the prazosin and placebo groups did not differ in any respect. Prazosin caused no demonstrable effect on clinical variables such as status of symptoms, heart rate, mean arterial pressure, and cardiothoracic ratio when compared with placebo. Prazosin also caused no demonstrable effect compared with placebo on absolute or percent changes in radionuclide variables at rest or on peak exercise, or on exercise time or exercise work load. In addition, prazosin had no consistent effect compared with placebo on plasma renin activity or plasma catecholamine levels. However, there was a slight but significant increase in weight (p less than 0.0001) and in plasma renin activity in the upright position (p less than 0.002) with time, as well as a tendency for the diuretic dose to increase with time in both groups. Thus, long-term prazosin therapy generally produces no demonstrable subjective or objective improvement in patients with stable, chronic class III CHF receiving digitalis and diuretic therapy.
Research Interests: Cardiology, Medicine, Heart Failure, Humans, Internal Medicine, and 15 morePlacebo, Congestive Heart Failure, Female, Male, Heart, Aged, Middle Aged, Adult, Ejection Fraction, Quinazolines, Random Allocation, Clinical Trials as Topic, Prazosin, Cardiovascular medicine and haematology, and physical exertion
Prostacyclin (PGI2) is a naturally occurring vasodilator and inhibitor of platelet aggregation that produces vasodilatation of the systemic, pulmonary and coronary vascular beds in animal models. Because the endogenous production of PGI2... more
Prostacyclin (PGI2) is a naturally occurring vasodilator and inhibitor of platelet aggregation that produces vasodilatation of the systemic, pulmonary and coronary vascular beds in animal models. Because the endogenous production of PGI2 is reduced in those with coronary arterial disease (CAD), it may have a therapeutic role in patients with ischemic heart disease. To assess its safety and efficacy in this clinical setting, 17 patients with stable angina and CAD received an incremental intravenous infusion of either PGI2 (n = 10) to a maximum dose of 10 ng/kg/min (average 9.8 +/- 0.8 [mean +/- standard deviation]), or diluent buffer solution (placebo) (n = 7). All patients who received PGI2 became flushed, but experienced no other adverse effects PGI2 caused an increase in heart rate (66 +/- 11 to 80 +/- 11 beats/min, p less than 0.001) and cardiac index (2.88 +/- 0.65 to 3.97 +/- 1.17 liters/min/m2, p less than 0.001) and a decrease in mean femoral arterial pressure (96 +/- 18 to 86 +/- 11 mm Hg, p less than 0.001), but no change in mean pulmonary arterial or capillary wedge pressure. Total systemic and pulmonary vascular resistance decreased significantly (p less than 0.001). In response to PGI2, mean coronary sinus blood flow did not change significantly (100 +/- 40 to 121 +/- 52 ml/min), but coronary vascular resistance decreased (1.07 +/- 0.40 to 0.83 +/- 0.36 U, p less than 0.001). No variable was altered by placebo infusion. PGI2 caused a marked increase in 6-keto PGF1 alpha (the stable metabolite of PGI2) concentrations in both arterial (42 +/- 29 to 567 +/- 216 pg/ml, p less than 0.001) and venous (46 +/- 31 to 604 +/- 229 pg/ml, p less than 0.001) blood but no demonstrable change in plasma renin activity. Thus, intravenous PGI2 to a dosage of 10 ng/kg/min is a safe and effective systemic, pulmonary and coronary arterial vasodilator in patients with CAD and stable angina pectoris.
Research Interests: Cardiology, Medicine, Humans, Internal Medicine, Hemodynamics, and 15 moreBlood Pressure, Female, Male, Heart rate, Middle Aged, Angina pectoris, Coronary Circulation, Prostaglandins, Vasodilation, Vascular Resistance, Random Allocation, epoprostenol, Prostacyclin, Cardiac output, and Cardiovascular medicine and haematology
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... of Minoxidil in Severe Congestive Heart Failure and Comparison to Hydralazine and Nitroprusside ROY V. MARKHAM, Jr., MD, ALYCE GILMORE, RN ... Unit at Parkland Memorial Hospital, Dallas, Texas, the technical assistance of R. Scott... more
... of Minoxidil in Severe Congestive Heart Failure and Comparison to Hydralazine and Nitroprusside ROY V. MARKHAM, Jr., MD, ALYCE GILMORE, RN ... Unit at Parkland Memorial Hospital, Dallas, Texas, the technical assistance of R. Scott Lyons and Tom Rhodes, and October 1 ...
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To assess the influence of ethanol on coronary arterial blood flow and dimensions, we measured coronary sinus blood flow in 35 subjects (23 men and 12 women, aged 38 to 69 years; (29 with and 6 without coronary artery disease) before and... more
To assess the influence of ethanol on coronary arterial blood flow and dimensions, we measured coronary sinus blood flow in 35 subjects (23 men and 12 women, aged 38 to 69 years; (29 with and 6 without coronary artery disease) before and during a 15- to 30-minute intracoronary infusion of (1) 5% dextrose in water (n = 15, controls) or (2) 5% dextrose in water (n = 20). In the controls heart rate, arterial pressure, and coronary sinus blood flow were unchanged. In those receiving ethanol at a rate that produced a concentration in coronary sinus blood of 285 +/- 102 (mean +/- SD) mg/dl, heart rate-systolic arterial pressure product was unchanged; coronary sinus blood flow rose 27 +/- 36%, and coronary vascular resistance fell 17 +/- 22% (p less than 0.05 in comparison to baseline); arterial-coronary sinus oxygen content difference fell (p less than 0.05), and epicardial coronary arterial dimensions were unchanged. Thus intracoronary ethanol increases coronary blood flow and decreases resistance without inducing a change in epicardial coronary dimensions, suggesting that its effect results from dilatation of the intramyocardial resistance vessels.
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Left ventricular dysfunction due to chronic right ventricular pressure overload is well documented in experimental animals, but is controversial in humans. Whether left ventricular dysfunction resolves following the relief of chronic... more
Left ventricular dysfunction due to chronic right ventricular pressure overload is well documented in experimental animals, but is controversial in humans. Whether left ventricular dysfunction resolves following the relief of chronic right ventricular pressure overload has not been studied. In this report, rapid improvement in both right and left ventricular function following successful percutaneous balloon valvuloplasty is described in a patient with severe isolated valvular pulmonic stenosis and biventricular dysfunction. It appears that: (1) geometric distortion played a major role in his reversible left ventricular dysfunction, and (2) severe biventricular dysfunction should not be a contraindication to valvuloplasty for valvular pulmonic stenosis.
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Research Interests: Mathematics, Cardiology, Medicine, Humans, Internal Medicine, and 15 moreStandard Deviation, Hemodynamics, Blood Pressure, Female, Male, Heart rate, Heart, Cardiac Catheterization, Middle Aged, Cardiovascular system, Erythrocytes, Blood Vessel, Pulmonary Artery, Cardiac output, and Cardiovascular medicine and haematology
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Research Interests: Humans, Female, Male, Heart, Acute Myocardial Infarction, and 13 moreMiddle Aged, Coronary Angiography, Myocardial Infarction, Adult, Coronary heart disease, Retrospective Studies, Prognosis, Coronary Artery Disease, Exercise Test, Heart Ventricles, The American, High risk, and Cardiovascular medicine and haematology
Abstract Although previous retrospective assessments have demonstrated good agreement between the results of the Fick method and those of indocyanine green dye and thermodilution in the measurement of cardiac output (CO), 1–3 they have... more
Abstract Although previous retrospective assessments have demonstrated good agreement between the results of the Fick method and those of indocyanine green dye and thermodilution in the measurement of cardiac output (CO), 1–3 they have suggested that the discrepancy between Fick and dye is exaggerated in patients with a low CO and in those with aortic or mitral regurgitation, whereas the Fick-thermodilution difference is not increased in these patients. As a result, thermodilution may be preferable to dye in those with a low CO or left-sided regurgitation. However, no previously published study has measured CO by all 3 techniques in a large number of patients, thereby allowing a direct comparison of dye and thermodilution. The present study was performed for this purpose.
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Research Interests: Cardiology, Medicine, Humans, Internal Medicine, Hemodynamics, and 15 moreBlood Pressure, Female, Male, Aspirin, Aged, Middle Aged, Adult, Coronary heart disease, Angina pectoris, Coronary Circulation, Coronary Artery Disease, Aorta, epoprostenol, Cardiovascular medicine and haematology, and Coronary Vessels
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... imaging. Brian G. Firth DPhil, MD Corresponding Author Contact Information , a ,Gregory J. Dehmer MD a , James R. Corbett MD a , Samuel E. Lewis MD a , Robert W. Parkey MD, FACC a and James T. Willerson MD, FACC a. a ...
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Abstract The best method for detecting early left ventricular (LV) dysfunction in patients with chronic aortic regurgitation is uncertain. Variables used previously to identify LV dysfunction have included (1) angiographic measurements to... more
Abstract The best method for detecting early left ventricular (LV) dysfunction in patients with chronic aortic regurgitation is uncertain. Variables used previously to identify LV dysfunction have included (1) angiographic measurements to identify an LV end-systolic volume index (LVESVI) ≥60 ml/m 2 , (2) echocardiographic measurements to identify LV end-systolic dimension (LVESD) ≥5.5 cm or LV fractional shortening ≤25%, and (3) depressed LV ejection fraction (EF) at rest and/or an LVEF or LVESVI that deteriorates with exercise as detected by myocardial scintigraphic measurements. The hypothesis was tested that radionuclide ventriculography with exercise allows earlier detection of important LV dysfunction in patients with aortic regurgitation than the other variables. In 15 consecutive asymptomatic or only minimally symptomatic patients (8 men and 7 women, mean age 44 years) with isolated 2 to 4+ aortic regurgitation (1) rest and exercise-gated radionuclide ventriculography, (2) M-mode echocardiography, and (3) LV angiography were performed. No other cause of LV dysfunction was apparent in 13 patients; 1 patient had moderate systemic arterial hypertension and 1 had 50% luminal diameter narrowing of the proximal left anterior descending coronary artery. Ten patients did not have an increase in LVEF >0.05 EF units at peak exercise (0.58 ± 0.11 to 0.50 ± 0.12, mean ± standard deviation [SD]) (Group 2), whereas 5 had a normal LVEF response to exercise (0.63 ± 0.08 to 0.69 ± 0.07) (Group 1). Eight of the 10 patients with abnormal LVEF responses to exercise had a decrease in LVEF >10% during exercise. The same 8 patients also had an increase in LVESVI with exercise, whereas the 5 patients with normal LVEF responses to exercise had normal or blunted LVESVI responses to exercise. Only 4 of the 10 patients with exercise-induced LV dysfunction had an angiographic LVESVI ≥60 ml/m 2 , and only 1 had an echocardiographically determined LVESD ≥5.5 cm. Serial follow-up rest and exercise scintigraphic and echocardiographic measurements were made in 8 of the patients a mean of 9.4 months after the initial measurements; 3 patients were in Group 1 and 5 in Group 2. The 5 patients in Group 2 again demonstated abnormal LV function during exercise stress, and 2 of the 3 patients in Group 1 then demonstrated an abnormal LV functional response during exercise. Therefore, it is concluded that (1) exercise radionuclide ventriculography identifies LV dysfunction earlier than traditionally used assessments, (2) LV dysfunction appears to persist in patients that demonstrate it and develop in others that did not have it originally, and (3) echocardiographic dilatation of the LVESD to 5.5 cm appears to be a late and relatively unusual occurrence.
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We assessed the value of two-channel Holter monitoring during the initial hours of hospitalization in patients with unstable angina pectoris (UAP) to identify those with severe coronary artery disease (CAD), variant angina, and/or poor... more
We assessed the value of two-channel Holter monitoring during the initial hours of hospitalization in patients with unstable angina pectoris (UAP) to identify those with severe coronary artery disease (CAD), variant angina, and/or poor prognosis over the next 3 months. Accordingly, 116 UAP patients had Holter monitoring for 27 +/- 7 (mean +/- SD) (range 12 to 50) hours following hospitalization. Of these, 24 evolved myocardial infarction (MI) during monitoring and 92 did not. Transient ST segment alterations occurred in 21 of the 92. Of these 21, 4 had variant angina, were treated with calcium antagonists, and did well. Each of the remaining 17 had severe fixed CAD (left main or three-vessel) (n = 12) and/or poor prognosis over the 3 months after discharge as manifested by death (n = 1), MI (n = 3), and/or severe angina (n = 3). In contrast, 71 patients did not demonstrate transient ST segment alterations: none had variant angina (p less than 0.001), nine had left main or three-vessel CAD (p less than 0.001), and 50 were alive and well 3 months after discharge (p less than 0.001). Ventricular tachycardia (VT) was demonstrated by Holter monitor in 5 of the 92 patients: four had three-vessel CAD and the other had severe persistent angina. Thus in patients hospitalized with unstable angina, transient ST segment alterations and/or VT on Holter monitor are specific predictors of "high-risk" subgroup UAP patients with left main or three-vessel CAD, variant angina, and/or impaired 3-month prognosis.
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This study was performed (1) to assess the value of postextrasystolic T wave alterations in identification of patients with cardiac disease and (2) to determine if their frequency depends on length of compensatory pause. In 52 patients a... more
This study was performed (1) to assess the value of postextrasystolic T wave alterations in identification of patients with cardiac disease and (2) to determine if their frequency depends on length of compensatory pause. In 52 patients a pacing catheter was placed in the right ventricular (RV) apex, and premature beats were programmed to occur 30 msec beyond RV refractory period. Postextrasystolic T wave alterations occurred in 32 patients, 13 with an 19 without coronary artery disease (CAD) (NS). Such alterations were also not related to presence of abnormal left ventricular (LV) ejection fraction (less than 0.55) or end-diastolic pressure (greater than 12 mm Hg). In 33 patients, premature beats were also introduced 330 msec beyond the RV refractory period to compare effects of long and short compensatory pauses on frequency of postextrasystolic T wave alterations. When the pause was near maximal, 18 patients had alterations in 60 ECG leads; when it was shorter, seven patients had alterations in 10 leads (p less than 0.001). Thus, judging from provoked postextrasystolic T wave alterations, such spontaneous changes appear neither sensitive nor specific in the identification of patients with cardiac disease. The frequency of postextrasystolic T wave changes depends on the length of the compensatory pause.
Research Interests: Cardiology, Medicine, Electrocardiography, Humans, Internal Medicine, and 13 moreFemale, Male, Heart rate, Aged, Middle Aged, Adult, Public health systems and services research, Time Factors, Propranolol, Coronary Artery Disease, Heart Ventricles, Quinidine, and Cardiovascular medicine and haematology
The present study was performed to determine the utility of radionuclide ventriculography (RNV) in conjunction with atrial pacing in the identification of individuals with coronary artery disease. Accordingly, left ventricular... more
The present study was performed to determine the utility of radionuclide ventriculography (RNV) in conjunction with atrial pacing in the identification of individuals with coronary artery disease. Accordingly, left ventricular end-diastolic volume index, end-systolic volume index, ejection fraction, and regional wall motion were measured with radionuclide ventriculography before and during atrial pacing in 37 patients: 27 with and 10 without (control subjects) coronary artery disease. In the control subjects, pacing caused a decrease in end-diastolic volume index (77 +/- 19 [mean +/- SD] ml/M2 at rest, 50 +/- 18 ml/M2 at peak pacing; p less than 0.001), a decrease in end-systolic volume index (34 +/- 14 ml/M2 at rest, 19 +/- 9 ml/M2 at peak pacing; p less than 0.001), an increase in ejection fraction (0.61 +/- 0.11 at rest, 0.66 +/- 0.11 at peak pacing; p = 0.006); and no deterioration in wall motion. In 16 patients with coronary artery disease who developed ECG and/or metabolic evidence of ischemia during pacing, end-diastolic volume index decreased (87 +/- 26 ml/M2 at rest, 69 +/- 24 ml/M2 at peak pacing; p less than 0.001), end-systolic volume index was unchanged (43 +/- 20 ml/M2 at rest, 44 +/- 21 ml/M2 at peak pacing; p = NS), ejection fraction decreased (0.55 +/- 0.12 at rest, 0.40 +/- 0.14 at peak pacing; p less than 0.001), and new wall motion abnormalities developed in 14. In 11 patients with coronary artery disease but no ECG or metabolic evidence of ischemia, pacing caused a decrease in end-diastolic volume index (80 +/- 26 ml/M2 to 61 +/- 31 ml/M2; p less than 0.001), a decrease in end-systolic volume index (36 +/- 17 ml/M2 to 28 +/- 20 ml/M2; p = 0.002), no change in ejection fraction (0.60 +/- 0.11 to 0.60 +/- 0.13; p = NS), and new wall motion abnormalities in four. Although the specificity of these scintigraphic measurements for the identification of patients with coronary artery disease was excellent (1.0), the combined sensitivity of all scintigraphic measurements was high only if ECG or metabolic evidence of ischemia was present: 0.94 in patients with evidence of ischemia but only 0.36 in those without ischemia. Thus radionuclide ventriculography during incremental atrial pacing is useful in the identification of patients with coronary artery disease only if ischemia is induced.
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Research Interests: Cardiology, Medicine, Stents, Humans, Hospital costs, and 15 moreFemale, Paradigm Shift, Male, Drug Delivery Systems, Myocardial Revascularization, Medicare, Middle Aged, Paradigm, Health Care Costs, Sirolimus, Multicenter Studies as Topic, Randomized Controlled Trials as Topic, Immunosuppressive Agents, Delivery of Health Care, and Cardiovascular medicine and haematology
Research Interests: Publishing, Conflict of Interest, Health / Medical Journalism, Clinical research, Biomedical Research, and 11 moreIndustry, United States, Physicians, Health Care System, Public health systems and services research, Patient Care, Drug Industry, Equipment and Supplies, United States Food and Drug Administration, guidelines as topic, and Cardiovascular medicine and haematology
Research Interests: Cardiology, Medicine, Humans, Internal Medicine, Hemodynamics, and 15 moreLeft Ventricular Assist Device, Blood Pressure, Female, Male, Heart rate, Middle Aged, Rest, Adult, Cardiac Output Monitoring, Ejection Fraction, Exercise Test, Heart Ventricles, Cardiac output, Left Ventricular, and Cardiovascular medicine and haematology
Endogenous modulators of platelet aggregability and vascular tone may play a part in coronary-artery disease. We therefore measured the release of prostaglandins and thromboxane into the coronary circulation in patients with various kinds... more
Endogenous modulators of platelet aggregability and vascular tone may play a part in coronary-artery disease. We therefore measured the release of prostaglandins and thromboxane into the coronary circulation in patients with various kinds of cardiac disease. Simultaneous coronary-sinus (CS) and ascending-aortic (AO) blood samples were obtained from 60 patients for measurement of 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha, a prostaglandin I2 metabolite) and of thromboxane B2 (TxB2). Samples from 45 of these patients were also tested for prostaglandin E2 (PGE2) and lactate. Patients with unstable angina pectoris who reported chest pain within 24 hours of study had higher TxB2 CS/AO ratios (5.8 +/- 2.8, mean +/- S.D.) than patients whose most recent anginal pain was more than 96 hours before study (1.3 +/- 0.6; P less than 0.05), than those with nonischemic chest pain (1.2 +/- 0.4; P less than 0.05), or with valvular or congenital nonischemic heart disease (1.2 +/- 0.6; P less than 0.05). Those whose most recent anginal pain occurred 24 to 96 hours before study were distributed bimodally: the majority had low TxB2 CS/AO ratios (range, 0.5 to 2.1) like the patients in the three aforementioned groups, whereas a few had markedly elevated values (range, 10.5 to 46.6). The 6-keto-PGF1 alpha and PGE2 CS/AO ratios and myocardial lactate extraction were not significantly different among the five groups. These data suggest that local thromboxane release is associated with recent episodes of angina in patients with unstable angina pectoris, but whether this release is a cause or an effect is not yet known.
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This study was performed to assess the influence of selective coronary arteriography on left ventricular volumes and ejection fraction in man. In 30 patients with assorted cardiac diseases, left ventricular end-diastolic and end-systolic... more
This study was performed to assess the influence of selective coronary arteriography on left ventricular volumes and ejection fraction in man. In 30 patients with assorted cardiac diseases, left ventricular end-diastolic and end-systolic volumes and ejection fraction were quantitated immediately before and after selective coronary arteriography. In 19 patients (Group A), contrast left ventriculography was performed immediately before and after selective coronary arteriography. In the remaining 11 patients (Group B), multigated equilibrium blood pool imaging was performed just before and after coronary arteriography. In both groups, mean systemic arterial pressure and heart rate did not change from just before the first to immediately before the second assessment of left ventricular volumes and ejection fraction, but left ventricular end-diastolic pressure increased. End-diastolic and end-systolic volume indexes, and ejection fraction did not change from just before to immediately after selective coronary arteriography. Therefore, selective coronary arteriography (1) consistently causes an increase in left ventricular end-diastolic pressure but (2) exerts no effect on left ventricular volumes and ejection fraction, even in patients with severely compromised left ventricular function.
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Methods We conducted a randomized trial comparing carotid-artery stenting with the use of an emboli-protection device to endarterectomy in 334 patients with coexisting conditions that potentially increased the risk posed by endarterectomy... more
Methods We conducted a randomized trial comparing carotid-artery stenting with the use of an emboli-protection device to endarterectomy in 334 patients with coexisting conditions that potentially increased the risk posed by endarterectomy and who had either a symptomatic carotid- ...