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G Sanz

Publications and source records attributed to G Sanz.

At least 19 recordsLinked to original sources

Arginine vasopressin infusion increases plasma levels of atrial natriuretic factor in humans.

Seven normal subjects underwent sequential 20-min infusion of arginine vasopressin (AVP) at 0.5 and 2 ng/(kg.min) and a complete right-side heart hemodynamic evaluation during the study to analyze the effect of this hormone on atrial natriuretic factor (ANF) secretion in humans and to elucidate whether this effect was primary or secondary to the hemodynamic or hormonal changes induced by AVP. Plasma ANF levels increased at the end of the first (P less than 0.05) and second (P less than 0.01) infusion periods. No significant changes in mean arterial, pulmonary artery, right and left atrial pressures were recorded during the study. Cardiac output (P less than 0.05) and heart rate (P less than 0.05) decreased, while total vascular resistances (P less than 0.05) increased with respect to basal values in both infusion periods. Plasma renin activity decreased (P less than 0.01) at the end of the infusion, while plasma aldosterone, epinephrine and norepinephrine showed no significant changes. We conclude that arginine vasopressin increases plasma ANF levels in humans and that this effect cannot be ascribed to hemodynamic or hormonal changes induced by this hormone, suggesting a direct effect of vasopressin on the atrial myocyte.

Adult

Pulmonary complications after long term amiodarone treatment.

BACKGROUND: Amiodarone hydrochloride is an antiarrhythmic agent useful in arrhythmias refractory to standard therapy. Although interstitial pneumonitis is known to be its most serious side effect, several aspects of amiodarone lung toxicity are still controversial. METHODS: Pulmonary side effects were examined in a sample of 61 symptomless patients (mean (SD) age 55 (7) years) who had had long term treatment with amiodarone (daily maintenance dose 400 mg), selected from 482 men attending the University of Barcelona myocardial infarction project. To allow for the confounding effects of coronary artery disease and tobacco history on lung function, 46 patients who had taken amiodarone for more than one year were matched with a control group from the same population. Subjects underwent measurement of lung volumes, arterial blood gas analysis and an incremental bicycle exercise test. RESULTS: Most lung function values were close to predicted values, though there was a small increase in resting alveolar-arterial oxygen tension difference (A-aDO2) at rest (4.8 (1.4) kPa in both groups). There were no differences in the results of forced spirometry or static lung volumes between the two groups, or in the fall in A-aDO2 from rest to exercise. There was a small difference between the amiodarone and the control group in transfer factor for carbon monoxide corrected for lung volume (KCO 1.67 (0.3) and 1.83 (0.3) mmol min-1 kPa-1 l-1 respectively) and in exercise capacity (140 (25) and 120 (30)w). Only three patients showed lung function impairment consistent with pneumonitis. No relation between lung function measures and cumulative doses of amiodarone or desethylamiodarone was found. CONCLUSIONS: The prevalence of clinically evident pulmonary side effects was 4.9%, which is lower than that reported in studies in which higher daily maintenance doses of amiodarone were given. The slightly lower KCO values and lower work load achieved by the patients taking amiodarone suggest a small effect of amiodarone in doses of 400 mg on lung function. A role for individual susceptibility to pulmonary complications of amiodarone treatment is suggested.

Amiodarone

[The predictive value of ventricular function during exercise after a myocardial infarct].

To assess the prognostic value of exercise left ventricular function, and if this test improves the prognostic value of clinical data and exercise test, 146 patients (mean age 56 +/- 9 years) underwent rest and exercise radionuclide angiography, 10 days after myocardial infarction. During follow-up (mean 16 +/- 5 months), 32 patients had new coronary events: 5 died, 9 had a new myocardial infarction and the remaining 18 developed unstable angina (Class III-IV of the CCS classification). Patients with new coronary events had more frequently severe left ventricular failure (Killip III-IV) (15% vs 3%; p less than 0.05) and postinfarction angina (32% vs 9%; p less than 0.01) than their counterparts. There were no differences regarding rest ejection fraction between both groups of patients. Exercise ejection fraction increased significantly (50 +/- 14% to 56 +/- 16%, p less than 0.001), while there was no change in patients with new coronary events (46 +/- 16% to 43 +/- 15%, NS). Logistic regression analysis including only clinical data identified postinfarction angina (p less than 0.01) and left ventricular failure (Killip III-IV) (p less than 0.01) as independent predictors of new coronary events. The sensitivity and specificity of the regression equation obtained with clinical data were 43% and 90%, respectively. Analyzing data from clinical variables, as well as exercise test and both, rest and exercise radionuclide angiography, logistic regression analysis identified, exercise ejection fraction (p less than 0.001), postinfarction angina (p less than 0.01) and rest ejection fraction (p less than 0.05) as independent predictors of new coronary events.(ABSTRACT TRUNCATED AT 250 WORDS)

Chi-Square Distribution

[Prognostic predictors of left ventricular aneurysm after myocardial infarct].

We have prospectively studied the prevalence and natural history of left ventricular aneurysm in a series of 386 consecutive male patients with an acute myocardial infarction. Definition of aneurysm was angiographic and based on a single plane left ventricular angiogram. There were 52 (13.5%) left ventricular aneurysms. Mean follow-up was 57 +/- 29 months (range 40-100). During this interval, 15 of the 52 patients died (29%). Univariate analysis showed that survivors had at admission significantly less prevalence of hypercholesterolemia, previous myocardial infarction and intraventricular conduction disturbances. In addition, their Killip class was better (p less than 0.02) and the left ventricular ejection fraction was higher (p less than 0.002). The survival rates of patients with ventricular aneurysm at 1, 3 and 5 years were 88, 82 and 75%, respectively. Left ventricular end diastolic pressure, number of diseased vessels and the presence of bifascicular block were independent predictors of survival. Stratification of patients according to the risk factors allowed identification of patients with excellent prognosis (those with left ventricular end diastolic pressure less than 20 mmHg, single vessel disease and no conduction disturbances) and others with high risk of death (left ventricular end diastolic pressure greater than or equal to 20 mmHg, three vessel disease and bifascicular block). Survival at 5 years for these two groups were 81% vs 50%, respectively (p less than 0.005).

Heart Aneurysm

[The effect of low-dose acetylsalicylic acid on platelet aggregation parameters in vitro].

In order to elucidate whether a single dose of 150 mg acetylsalicylic acid three times a day, provokes significant changes into platelet aggregation, we analyzed a group of 50 patients who underwent coronary revascularization. During 48 hours before surgery, all patients received 100 mg dipyridamole orally every 6 hours and 1 hour after the end of the operation 100 mg dipyridamole via nasogastric tube. Patients were then randomized into three groups to receive 3 times a day a capsule containing: 50 mg acetylsalicylic acid, 50 mg acetylsalicylic acid plus 75 mg dipyridamole or placebo. Before the antiplatelet therapy was started, the day of the operation and 5 days after the onset of the treatment, blood samples were taken to determine platelet aggregation (turbidimetric technique) and the thromboxane A2 liberation. The three groups were comparable for all the studied clinical and angiographic variables. Preoperative dipyridamole did not provoke significant changes in platelet aggregation (acetylsalicylic acid group 86.5 +/- 10% vs 71 +/- 28.8%; acetylsalicylic acid + dipyridamole group 81.5 +/- 7.8% vs 75.3 +/- 22.7%; placebo group 83.7 +/- 8.9% vs 70 +/- 21.5%). After 5 days of treatment with acetylsalicylic acid, both groups under active treatment showed a significant (p less than 0.001) decrease of aggregability (acetylsalicylic acid 12.8 +/- 4.4%; acetylsalicylic acid + dipyridamole 20.5 +/- 17%; placebo 72 +/- 21.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aspirin

Impaired response of atrial natriuretic factor to blood volume expansion in acute right ventricular infarction.

To assess the role of atrial natriuretic factor (ANF) in right ventricular (RV) infarction, 30 patients with inferior wall acute myocardial infarction (15 with RV involvement) and normal left heart filling pressures were studied 39 +/- 12 hours after the onset of symptoms. Serial measurements of cardiac output, right atrial, pulmonary artery and pulmonary wedge pressures, as well as plasma ANF, plasma renin activity, plasma aldosterone and vasopressin were obtained before and 30 minutes after acute volume expansion to raise wedge pressure greater than or equal to 20 mm Hg. Baseline mean right atrial pressure and plasma ANF levels were greater in patients with than without RV infarction (8 +/- 3 vs 5 +/- 2 mm Hg; p less than 0.0001, and 4.6 +/- 2.9 vs 2.7 +/- 1.5 fmol/ml; p less than 0.05, respectively). There were no differences in other baseline hemodynamic or humoral parameters between both groups. After volume expansion, pulmonary wedge pressure was similar in both groups, but right atrial pressure increased to higher levels in patients with RV infarction (19 +/- 2 vs 14 +/- 2 mm Hg; p less than 0.0001). Despite this greater stimulus for ANF secretion, the increase in plasma ANF was less pronounced in patients with RV infarction (63 +/- 81 vs 455 +/- 417%; p less than 0.002), especially among those with paroxysmal supraventricular tachyarrhythmias. Thus, despite higher baseline plasma levels of ANF, response to volume loading is markedly attenuated in patients with RV infarction complicating an inferior wall acute myocardial infarction.

Adult

Clinical and angiographic features and prognostic significance of early postinfarction angina with and without electrocardiographic signs of transient ischemia.

PURPOSE: The goal of the study was to characterize the clinical and angiographic characteristics and the prognostic significance of early postinfarction angina associated or unassociated with ST-T changes. PATIENTS AND METHODS: Four hundred forty-nine consecutive patients surviving an acute myocardial infarction and catheterized before hospital discharge were included. They were closely monitored in the coronary care unit and a 12-lead electrocardiogram (ECG) was promptly obtained before the administration of nitroglycerin whenever chest pain suggestive of ischemia occurred. Complete follow-up information was obtained for all patients a mean of 14 +/- 8 months after the qualifying infarction. RESULTS: Early postinfarction angina occurred in 164 patients. Transient ST-T changes were documented during pain in 79 patients and were absent in 85. Compared with patients without postinfarction angina, patients with angina without ST-T changes were older and had a more frequent past history of angina (42% versus 28%, p = 0.01). They also more often had a non-Q-wave myocardial infarction with lower peak creatine kinase blood level elevation. At angiography, patients with angina had more extensive coronary artery disease (1.9 +/- 0.8 diseased vessels per patient versus 1.6 +/- 0.8, p less than 0.05) and more left ventricular segments at jeopardy by a significant coronary artery stenosis (1.5 +/- 1.1 versus 1.2 +/- 1.1, p less than 0.05). The presence of ST-T changes during chest pain was associated with a further increase in the severity of coronary artery disease (2.1 +/- 0.8 diseased vessels per patient, p less than 0.05) and with a less well-developed collateral circulation (18% versus 34% of patients, p = 0.01) that was more often compromised by a coronary artery stenosis (22% versus 8% of patients, p = 0.008). In-hospital infarct extension occurred in 2% of patients without angina, 3.5% of patients with angina without ECG changes, and 28% of patients with angina and ST-T changes (p less than 0.01). The 2-year survival was similar in the first two groups (90% and 96%), and poorer (83%, p = 0.02) in patients with ST-T changes. Survival rates without myocardial infarction were respectively 80%, 78%, and 67% (p less than 0.004). CONCLUSION: A gradient in the severity of coronary artery disease and in the extent of myocardium at jeopardy exists from patients with no postinfarction angina to patients with angina and to patients with angina accompanied by ECG signs of ischemia. The presence of ST-T changes during pain indicates a much less favorable clinical outcome.

Angina Pectoris

[Non-sedative antihistaminics and binding to central and peripheral H1 histamine receptors].

Four non-sedating antihistamines (astemizole, cetirizine, loratadine and terfenadine) were investigated for in vitro and ex vivo binding to histamine-H1 receptors in guinea-pig cerebellum and lung. In vitro, all the drugs dissociated slowly from H1 receptors (half-times greater than or equal to 100 min), Ki,app-values decreased with longer incubation times for potent lipophylic agents (astemizole and terfenadine) Ki,app-values were lower with more dilute tissue suspensions. In optimized assay conditions astemizole showed a Ki,app-value of 0.2 microM. Terfenadine, cetirizine and loratadine bound with 30-, 80- and 100-times lower affinity to H1 receptors. The occupancy of lung and cerebellar H1 receptors was investigated after oral administration of various dosages of the drugs and at several times after drug administration, using ex vivo binding techniques. Astemizole was a very potent compound showing complete differentiation between lung and cerebellar receptor occupation (with 0.63 mg/kg: 70% of lung H1 receptors were occupied, with less than 10% of cerebellar H1 receptor occupancy). A 7-times higher dose of terfenadine was required to induce the same effect. Astemizole produced a rapid and complete occupancy of lung receptors, which was maintained up to 72 h after administration. In contrast, terfenadine produced a peak effect at 1 h and was completely eliminated from lung receptors in 24 h. Loratadine and cetirizine only poorly differentiated between lung and cerebellar receptor occupancy (at 2.5 mg/kg: 70 and 60% of lung receptor occupancy, 50 and 70% of cerebellar receptor occupancy).(ABSTRACT TRUNCATED AT 250 WORDS)

Astemizole

[Chronic lymphatic leukemia. I. Clinico-biological features and survival analysis. Study of 187 patients].

A review was carried out of 187 previously untreated cases of chronic lymphocytic leukaemia diagnosed between 1969 and 1988. The median age of the patients was 65 years (range, 36-87). There were 118 males (M/F ratio, 1.7). In accordance with Rai's staging system the patients were distributed as follows: 0.29%; I, 20%; II, 25%; III, 13%; IV, 13%, and according to Binet's staging the distribution was: A, 55%; B, 21%; C, 24%. The most frequently found physical findings were lymph node enlargement (55%), splenomegaly (32%) and hepatomegaly (28%). Anaemia was present in 20% of the cases and thrombocytopenia in 13%. The mean lymphocyte count was 62 x 10(9)/L (range, 6-475 x 10(9)/L). Bone marrow infiltration of over 80% was seen in 46% of the patients. Bone marrow biopsy was performed on 97 patients, the diffuse pattern of involvement being most commonly found (44%). Increased BUN (55%), alkaline phosphatase (42%) and LDH (38%) were the most frequent biochemical alterations. Hypogammaglobulinaemia was present in 55% of the patients, IgM being the most commonly affected immunoglobulin (66%). Monoclonal gammopathy was seen in 4% of the cases. LDT, measured in 75 patients, was less than a year in 32%. No antileukaemic drugs were needed in 34% of the patients. When concluding this study, 100 patients had died. The median survival was 57 months and death was related to chronic lymphocytic leukaemia in 53% of such patients.

Actuarial Analysis

[Chronic lymphatic leukemia. II. Analysis of prognostic factors and development of survival predicting models. Study of 187 patients].

The univariate analysis of prognostic factors showed the value of clinical variables (age, symptoms, lymph node enlargement, splenomegaly, hepatomegaly, clinical stage), haematological variables (haemoglobin, platelet count, leucocyte count, lymphocyte count, bone marrow involvement and biopsy pattern, cleaved lymphocytes, prolymphocytes, LDT) and biochemical variables (BUN, creatinine, calcium, phosphorus, uric acid and albumin). The multivariate analysis chose the combination of Rai's stage, age, cervical lymph node involvement, phosphorus and BUN. Two predictive models capable of separating appropriately low, intermediate and high risk groups were developed and validated. The results were compared with others in the literature. The interest of predictive models arising from multivariate analysis is stressed.

Adult

Comparative effects of the aromatase inhibitor R76713 and of its enantiomers R83839 and R83842 on steroid biosynthesis in vitro and in vivo.

R76713 (6-[(4-chlorophenyl)(1H-1,2,4-triazol-1-yl)methyl]-1-methyl-1H- benzotriazole) is a selective, non-steroidal aromatase inhibitor containing an asymmetric carbon atom. In this paper, we compare the effects of R76713 (racemate) with its enantiomers R83839 (the levo-isomer) and R83842 (the dextro-isomer) on steroid biosynthesis in rat cells in vitro and in the rat in vivo. In rat granulosa cells, aromatase activity was inhibited by 50% at concentrations of 0.93 nM of R76713, 240 nM of R83839 and 0.44 nM of R83842, revealing a 545-fold difference in activity between both enantiomers. Up to 1 microM, none of the compounds had any effect on steroid production in primary cultures of rat testicular cells. Above this concentration all three compounds showed a similar slight inhibition of androgen synthesis with a concomitant increase in the precursor progestins, indicative for some effect on the 17-hydroxylase/17,20-lyase enzyme. In rat adrenal cells none of the compounds showed any effect on corticosterone synthesis. At concentrations above 1 microM there was an increase in the levels of 11-deoxycorticosterone pointing towards an inhibition of the 11-hydroxylase enzyme. This increase was more pronounced for R83839 than for R76713 and R83842. In vivo, in PMSG-primed rats, R83842 reduced plasma estradiol by 50%. 2 h after oral administration of 0.0034 mg/kg, whereas 0.011 mg/kg of R76713 and 0.25 mg/kg of R83839 were needed to obtain the same result. Oral administration of up to 20 mg/kg of the compounds did not significantly affect plasma levels of adrenal steroids in LHRH/ACTH-injected rats. Plasma testosterone was lowered at 10 and 20 mg/kg of R83842 and at the highest dose (20 mg/kg) of R76713 and R83839. In conclusion, the present study shows that the aromatase inhibitory activity of R76713 resides almost exclusively in its dextro-isomer R83842. R83842 exhibits a specificity for aromatase as compared to other enzymes involved in steroid biosynthesis of at least a 1000-fold in vitro as well as in vivo. This confirms the extreme selectivity previously found for the racemate.

Adrenal Cortex Hormones

R 75251, a new inhibitor of steroid biosynthesis.

R 75251, a new imidazole derivative, inhibited the conversion of androgens to estrogens, of progestins to androstenedione and testosterone, and of 11-deoxycorticosterone to corticosterone in human placenta microsomes, subcellular fraction of rat testis, bovine adrenocortical mitochondria, in cultured rat granulosa, testicular and adrenal cells, respectively. In vitro, no effect on cholesterol synthesis and cholesterol side-chain cleavage was found at concentrations up to 10 microM. In rat granulosa cells, no effect on progesterone production was detected. In vitro, no effect on steroid radioligand binding was observed. In male volunteers, a single dose of 300 mg of R 75251 significantly lowered plasma testosterone and estradiol for 24 hours and increased plasma concentration of 17 alpha-hydroxyprogesterone and progesterone. As compared with ketoconazole high dose (600 mg b.i.d), R 75251 (300 mg b.i.d) was at least as efficacious as inhibitor of testosterone synthesis when studied during ACTH stimulation. In contrast to ketoconazole, R 75251 did not significantly affect circulating adrenal androgen levels in male volunteers. Precursors of gluco- and mineralocorticoids such as 11-deoxycortisol and 11-deoxycorticosterone accumulated more than after ketoconazole administration. The data show that the cytochrome P450-dependent aromatase, 17-hydroxylase/17,20-lyase, and 11-hydroxylase are the target enzymes for R 75251.

Adrenocorticotropic Hormone

Does low-dose aspirin prevent aortocoronary vein bypass graft occlusion? The Spanish Group for Aortocoronary Bypass Follow-up (GESIC Study).

Although the importance of antiplatelet treatment in preventing early bypass occlusion has been clearly recognized, questions regarding the optimal drug regimen remain. To study the efficacy of low-dose aspirin, alone or in combination with dipyridamole, 927 consecutive patients were enrolled in a multicenter, randomized, double-blind, placebo-controlled trial comparing aspirin, 50 mg t.i.d., aspirin, 50 mg t.i.d. plus dipyridamole, 75 mg t.i.d., and placebo. Both aspirin and aspirin plus dipyridamole reduced the occlusion rate of distal anastomoses, but only aspirin plus dipyridamole reduced the number of patients with at least one occluded graft. Logistic regression analysis identified distal vessel diameter, bypassed artery, graft type, and postoperative antiplatelet treatment as independent predictors of graft patency.

Aged

Risk stratification and prognosis of patients with recent onset angina.

We prospectively assessed coronary artery disease and natural history in a series of 104 patients (99 males, mean age 52 +/- 8 years) admitted with recent onset angina (defined as a history of angina of less than 1 month duration). Coronary angiography showed one-vessel disease in 31, two-vessel disease in 22 and three-vessel disease in 14; 37 patients had normal coronary arteries. After a mean follow-up of 36 (range 1 to 52) months, one patient died, 13 sustained a myocardial infarction and 21 underwent surgery. The univariate analysis showed four of 12 clinical features derived from clinical history and data from CCU (exertional angina (P less than 0.001), and recurrence of angina (P less than 0.05)) to be associated with the presence of coronary artery disease. These clinical features were termed clinical risk characteristics. Three-year probability of medical events (death or acute myocardial infarction) for patients with 0-1 clinical risk characteristics was 0 and that of combined events (need for revascularization with or without a preceding medical event) 0.11, whereas patients with 2 or more risk characteristics had probabilities of 0.27 and 0.49, respectively. Multivariate analysis identified the number of clinical risk characteristics as the only independent predictor of medical events (P less than 0.002) and a positive thallium stress test (P less than 0.0001), the number of clinical risk characteristics (P less than 0.002) and the number of involved arteries (P less than 0.002), as independent predictors of combined events.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Does left ventricular aneurysm influence survival after acute myocardial infarction?

To test whether left ventricular aneurysm independently influences survival after acute myocardial infarction, a series of 386 consecutive men aged 60 years or less, were followed up for 57 (40-100) months. Catheterization was performed 1 month following the infarct. Aneurysm, defined as a diastolic outward bulging with akinetic or dyskinetic systolic motion, was diagnosed in 52 patients (13.5%). Mortality was higher (29% vs 14%; P less than 0.02) in patients with left ventricular aneurysm; their probability of survival at 60 months was 75% vs 90% in patients without aneurysm. Cox regression analysis for the whole population identified ejection fraction, bifascicular block, number of diseased vessels and angina after infarction as the only independent predictors of survival; when adjusted for these variables, differences in mortality between patients with and without aneurysm were no longer significant. To investigate further the role of aneurysm in survival, the 52 patients presenting with left ventricular aneurysm were matched with 52 of the remaining 334 patients according to the following baseline variables: ejection fraction, number of diseased vessels, left ventricular end-diastolic pressure, and bifascicular block. The survival curves of these two subsets were similar (mortality rates of 75% and 82%, respectively). Cox regression analysis of the whole cohort of 104 patients selected bifascicular block and the number of diseased vessels, but not left ventricular aneurysm, as independent predictors of outcome.

Follow-Up Studies

Bone marrow biopsy in myelodysplastic syndromes: morphological characteristics and contribution to the study of prognostic factors.

Ten characteristics of bone marrow (BM) biopsies in paraffin sections, obtained at diagnosis from patients with myelodysplastic syndromes (MDS) classified according to the FAB criteria, were analysed to identify both the most relevant morphologic data and any possible influence on survival. Agreement between two observers was obtained for 94% of the data. BM cellularity was increased in 63% of the cases and was higher in refractory anaemia with excess of blasts (RAEB). RAEB in transformation (RAEB-t) and chronic myelomonocytic leukaemia (CMML) (P = 0.001). Dysmegakaryopoiesis and dyserythropoiesis were present respectively in 83% and 72% of the cases, with slight differences among the FAB subtypes. Abnormal localization of immature precursors (ALIP) was found in more than half of the cases and somewhat more frequently seen in the RAEB + RAEB-t + CMML group (P = 0.07). Eosinophilia, plasmacytosis and reticulin fibrosis were evident in 26%, 18% and 47% of the cases respectively. Cellularity (P = 0.006), eosinophilia (P = 0.009) and, to some extent, dysmegakaryopoiesis (P = 0.07) bore a certain relationship with survival on univariate analysis. The presence of ALIP was not seen to affect the outcome. Multivariate analysis showed that the cellularity and presence of dysmegakaryopoiesis, in BM biopsy, added significant independent prognostic information to that achieved with age, platelet count and proportion of blast cells in BM aspirate, three variables with proven prognostic value in MDS patients. Using a regression model including these five characteristics we have stratified the patients into low, intermediate and high-risk groups with different survivals (P = 0.00001). The present findings show that BM biopsy is able to provide both morphological characteristics and information about the prognosis of survival, and should thus be included in the initial evaluation of MDS.

Adult

Prevention of early aortocoronary bypass occlusion by low-dose aspirin and dipyridamole. Grupo Español para el Seguimiento del Injerto Coronario (GESIC)

To analyze the efficacy of low-dose aspirin in preventing early aortocoronary vein graft occlusion, 1,112 consecutive patients were enrolled in a multicenter, randomized, double-blind, placebo-controlled trial comparing 50 mg t.i.d. aspirin, 50 mg aspirin plus 75 mg t.i.d. dipyridamole, and placebo. All patients received 100 mg q.i.d. dipyridamole for 48 hours before surgery, and assigned treatment was started 7 hours after surgery. Vein graft angiography was performed in 927 patients (83%) within 28 days of surgery (mean, 10 days). Aspirin plus dipyridamole significantly (p = 0.017) reduced the occlusion rate of distal anastomoses from 18% (placebo) to 12.9%. Occlusion rate in the aspirin group was 14%, which approached statistical significance (p = 0.058). Furthermore, only aspirin plus dipyridamole reduced (p = 0.01) the number of patients with occluded grafts (placebo, 33%; aspirin, 27.1%; aspirin plus dipyridamole, 24.3%). Mediastinal drainage was slightly higher (p = 0.04) in the aspirin plus dipyridamole group (713 +/- 456 ml) than in the other two groups (placebo, 670 +/- 437 ml; aspirin, 629 +/- 337 ml), but hospital mortality (average, 4.6%) and early reoperation (average, 3.9%) rates were similar among the three groups. Thus, low-dose aspirin plus dipyridamole safely improves early saphenous vein aortocoronary graft patency; this effect is an added benefit to a preoperative regimen of dipyridamole.

Aged