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Biomedical subjects

F Van de Werf

Publications and source records attributed to F Van de Werf.

At least 19 recordsLinked to original sources
PubMed1995

Stroke after thrombolysis. Mortality and functional outcomes in the GUSTO-I trial. Global Use of Strategies to Open Occluded Coronary Arteries.

BACKGROUND: Stroke is the most feared complication of thrombolysis for acute myocardial infarction because of the resulting mortality and disability. We analyzed the incidence, timing, and outcomes of stroke in an international trial. METHODS AND RESULTS: Patients were randomly assigned to one of four thrombolytic strategies. Neurological events were confirmed clinically and anatomically and were adjudicated by a blinded committee. Stroke survivors, categorized by residual deficit and disability, assessed their quality of life with a time trade-off technique. Multivariable regression identified patient characteristics associated with intracranial hemorrhage. Over-all, 1.4% of the patients had a stroke (93% anatomic documentation). The risk ranged from 1.19% with streptokinase/subcutaneous heparin therapy to 1.64% with combination thrombolytic therapy (P = .007). Primary intracranial hemorrhage rates ranged from 0.46% with streptokinase/subcutaneous heparin to 0.88% with combination therapy (P < .001). Of all strokes, 41% were fatal, 31% were disabling, and 24% were nondisabling, with no significant treatment-related differences. Stroke subtype affected prognosis: 60% of patients with primary intracranial hemorrhage died and 25% were disabled versus 17% dead and 40% disabled with nonhemorrhagic infarctions. Patients with moderate or severe residual deficits showed significantly decreased quality of life. Advanced age, lower weight, prior cerebrovascular disease or hypertension, systolic and diastolic blood pressures, randomization to tissue plasminogen activator, and an interaction between age and hypertension were significant predictors of intracranial hemorrhage. CONCLUSIONS: Stroke remains a rare but catastrophic complication of thrombolysis. Additional studies should assess the net clinical benefit of thrombolysis in high-risk subgroups, particularly the elderly and patients with prior cerebrovascular events.

Aged↗
PubMed1995

Impaired myocardial tissue perfusion early after successful thrombolysis. Impact on myocardial flow, metabolism, and function at late follow-up.

BACKGROUND: Impaired tissue reperfusion after successful recanalization of an epicardial coronary artery has been documented both in animals and in patients with acute myocardial infarction. Whether this phenomenon can be demonstrated with positron emission tomography (PET) and whether it has an effect on late recovery of flow, metabolism, and function are unknown. METHODS AND RESULTS: Thirty patients with an acute myocardial infarction and TIMI flow grade 3 of the infarcted vessel at 90 minutes after thrombolytic therapy were studied. Within 24 hours after thrombolysis, at 5 days and at 3 months, myocardial blood flow was measured with 13NH3. 18FDG uptake was measured at 5 days. Radionuclide left ventricular angiograms were acquired at 5 days and at 3 months. In 11 patients (37%), regional myocardial flow was severely impaired (< 50% of normally perfused myocardium) despite successful thrombolysis. No recovery of left ventricular function occurred in any of these patients at 3 months. In 12 patients (40%), intermediate flows (50% to 75% of normal) were found, with functional improvement after angioplasty only in regions with a PET mismatch. Seven patients (23%) had high flow values early after successful thrombolysis (> 75% of normal) and showed preserved regional contractile function at 3 months. CONCLUSIONS: This study is the first demonstration with PET of impaired myocardial tissue perfusion in patients with an acute myocardial infarction after successful thrombolysis. Functional recovery of the reperfused myocardium is observed only when adequate tissue flow is restored. PET may be helpful in selecting patients in whom additional revascularization can improve recovery of left ventricular function.

Aged↗
PubMed1995

Benefit of thrombolytic therapy is sustained throughout five years and is related to TIMI perfusion grade 3 but not grade 2 flow at discharge. The European Cooperative Study Group.

BACKGROUND: Long-term follow-up in patients treated with thrombolysis for acute myocardial infarction thus far has been reported in a few studies only, and no long-term follow-up is available for patients who underwent additional percutaneous transluminal coronary angioplasty (PTCA). This report describes 5-year survival as collected in patients who received placebo, recombinant tissue plasminogen activator (rTPA), or rTPA with additional immediate PTCA in two European Cooperative Study Group trials. Determinants for long-term survival were assessed in 1043 patients discharged alive. METHODS AND RESULTS: Five-year follow-up information on mortality was collected. Hospital mortality was lower after rTPA than placebo (2.5% versus 5.7%, P = .04) and higher after rTPA with immediate PTCA compared with rTPA without additional intervention (6.0% versus 2.2%, P = .07). Of the 1043 hospital survivors, data were available for 923 patients, of whom 109 died. In the placebo group, mortality after hospital discharge was 10.7% versus 11.0% in the comparative rTPA group. The patients treated with rTPA and immediate PTCA had a mortality rate of 10.5% versus 8.9% in the rTPA group without PTCA (all P = NS). Significant determinants of mortality in multivariate proportional hazards analysis were enzymatic infarct size, indicators of residual left ventricular function, number of diseased vessels and TIMI perfusion grade at discharge. Patients with TIMI grade 2 flow had mortality rates similar to those with TIMI flow grades 0 and 1, while prognosis was better in patients with TIMI flow grade 3. CONCLUSIONS: The initial in-hospital benefit of thrombolysis with intravenous rTPA is maintained throughout 5 years, with no early or late beneficial effect of systematic immediate PTCA. Enzymatic infarct size, left ventricular function, and extent of coronary artery disease are predictors for long-term survival. TIMI perfusion grade 2 at discharge should be considered as an inadequate result of therapy.

Angioplasty, Balloon, Coronary↗
PubMed1995

Can dobutamine echocardiography distinguish necrotic from ischemic myocardium, early after myocardial infarction?

UNLABELLED: The aim of this study was to evaluate the usefulness of dobutamine echocardiography (DE) in distinguishing necrotic from ischemic myocardium in infarct zones. We performed DE in 39 patients, 3 to 5 days after admission for a first, acute myocardial infarction, treated with thrombolysis. DE was considered positive if wall motion in the infarct zone worsened progressively during increasing dose of dobutamine or if wall motion in the infarct zone initially improved at low dose of dobutamine and deteriorated at higher dose. The results of DE were correlated to the evolution of wall motion in the infarct zone after 3 months and to the need for supplementary balloon dilatation. In 15 of the 39 patients, there was evidence of residual ischemia in the infarct zone. Twenty of the 39 patients had a positive dobutamine echocardiogram. Eleven of these 20 patients had evidence of residual ischemia in the infarct zone. They showed generalized changes of wall motion in the total infarct territory during DE. The other 9 patients demonstrated only localized changes of wall motion in isolated segments of the infarct zone during DE. None of these patients had evidence of residual ischemia. IN CONCLUSION: DE seems worthwhile in the detection of residual ischemia in the region of infarction. To reduce the number of false positive DE early after myocardial infarction, only extensive changes of wall motion in the total infarct territory should be accepted as indicative of residual ischemia in the infarct zone.

Dobutamine↗
PubMed1995

Left ventricular quantification with breath-hold MR imaging: comparison with echocardiography.

To evaluate the reproducibility of measurements of left ventricular (LV) dimensions, function, and myocardial mass, segmented k-space gradient-recalled-echo (GRE) magnetic resonance (MR) imaging was performed on two occasions on 12 healthy volunteers. To compare the MR data, all volunteers underwent a two-dimensional echocardiography with determination of LV dimensions and function. The left ventricle was imaged during breath-hold by consecutive, contiguous short-axis views at end-diastole and end-systole. An average of eight short-axis views was needed to encompass the whole left ventricle. This fast MR sequence limited the total acquisition time to 12 min. LV volumes and masses were calculated after manual delineation of epicardial and endocardial surfaces by two observers in a blinded fashion. Interstudy variability varied between 4.1% and 10.3% for LV end-diastolic volume and end-systolic volume, respectively. Differences in interobserver variability were smaller and varied between 3.6% and 7.3% for LV ejection fraction and end-diastolic volume, respectively. Intraobserver variabilities ranged between 2.0% and 7.0% for LV ejection fraction and end-systolic volume, respectively. These variability percentages agree very well with other studies in literature using other MR sequences. No significant differences in LV dimensions or function were found between MR imaging and echocardiography. In conclusion, this MR sequence allows fast and reproducible LV quantification.

Adult↗
PubMed1995

Determinants of transmitral inflow pattern 10-14 days after acute myocardial infarction.

AIM: The administration of thrombolytic therapy after an acute myocardial infarction can reduce the size of the infarct and improve left ventricular function. We used pulsed Doppler to assess left ventricular diastolic function after an acute myocardial infarction in patients treated with recombinant tissue plasminogen activator (rTPA). PATIENTS AND METHODS: We studied 104 patients after an acute myocardial infarction, 48 treated with a placebo and 56 with rTPA. They were compared with 36 age-matched controls. The Doppler parameters measured included the early peak in diastolic flow velocity, the peak during atrial contraction, the atrial: early ratio, mean deceleration, deceleration time, and half-filling fraction. Doppler parameters for large and small infarct sizes were compared. RESULTS: The Doppler parameters did not differ between treatment groups. Compared with the normal controls, significant differences were observed in both treatment groups for the early peak (placebo P < 0.05; rTPA P < 0.001), the atrial: early ratio (placebo P < 0.05; rTPA P < 0.01), and the half-filling fraction (P < 0.001 for both). In patients with large infarcts, the atrial peak was depressed (P = 0.008). Multivariate analysis showed that end-diastolic pressure, age, end-systolic volume, and regional wall motion parameters were major predictors of Doppler parameters.

Adult↗
PubMed1995

Comparison of a low-molecular-weight heparin (nadroparin calcium) and unfractionated heparin as adjunct to coronary thrombolysis with alteplase and aspirin in dogs.

BACKGROUND: Low-molecular-weight heparins may have a higher benefit to risk ratio than unfractionated heparin in preventing perioperative thrombosis. The antithrombotic effects of low-molecular-weight heparins, given as adjunctive therapy to alteplase and aspirin, have not previously been compared with those of unfractionated heparin in experimental models of coronary artery thrombosis. METHODS: Occlusive coronary thrombosis was induced in 5 groups of 10 dogs by placing a copper coil into the left anterior descending coronary artery. After 1 h of occlusion, intravenous alteplase (0.1 mg/kg bolus followed by 0.01 mg/kg/min for 30 min), and aspirin (bolus of 5 mg/kg) were administered in combination with one of the following study treatments given intravenously for 2 h: placebo (group 1); unfractionated heparin (200 IU/kg bolus followed by 100 IU/kg/h, group II); the low-molecular weight heparin, nadroparin calcium, in three different doses (100 IU/kg bolus followed by 50 IU/kg/h, group III; 200 IU/kg bolus followed by 100 IU/kg/h, group IV; and 300 IU/kg followed by 150 IU/kg/h, group V). Coronary patency was assessed with angiography at 10 min intervals and hemostasis parameters were measured at baseline, after 1 h of occlusion, and 30 and 120 min after commencing drug administration. RESULTS: Optimal reperfusion [Thrombolysis in Myocardial Infarction (TIMI) flow grade 3 without reocclusion] was more frequently observed in groups II (6/10), IV (8/10) and V (9/10) than in groups I (1/10) and III (3/10) (P < 0.05). Groups II and IV had similar patency rates (P = NS) and were therefore assumed to represent equivalent antithrombotic doses. Both nadroparin calcium and unfractionated heparin effectively prevented new thrombin generation as shown by repeated measurements of thrombin-antithrombin III complex levels in plasma. At equivalent antithrombotic doses, nadroparin calcium (group IV) was associated with significantly lower steady state values than standard heparin (group II) for activated partial thromboplastin time (41.3 +/- 48.9 versus 134.7 +/- 61.6 s), anti-Xa levels (2.4 +/- 0.5 vs 3.4 +/- 0.9 U/ml) and anti-IIa levels (0.8 +/- 0.1 versus 2.1 +/- 0.7 U/ml). CONCLUSION: Both nadroparin calcium and unfractionated heparin significantly enhance alteplase-induced thrombolysis in aspirin-treated dogs. At equivalent antithrombotic doses, nadroparin calcium was associated with less prolongation of the activated partial thromboplastin time and lower steady-state anti-Xa and anti-IIa activities.

Animals↗
PubMed1994

High yield production and purification of recombinant staphylokinase for thrombolytic therapy.

Recombinant plasmids were constructed in which the signal sequence of the sak42D and the sakSTAR staphylokinase genes were replaced by an ATG start codon and which express staphylokinase under the control of a tac promoter and two Shine-Dalgarno sequences in tandem. Induction of transfected E. coli TGl cells in a bacterial fermentor produced intracellular staphylokinase representing 10 to 15% of total cell protein. Gram quantities of highly purified recombinant staphylokinase were obtained from cytosol fractions by chromatography, at room temperature, on SP-Sepharose and on phenyl-Sepharose columns, with yields of 50 to 70 percent. The material, at a dose of 4 mg/kg, did not produce acute reactions or affect body weight in mice. Intravenous administration of 10 mg SakSTAR over 30 minutes in five patients with acute myocardial infarction induced complete coronary artery recanalization, without associated fibrinogen degradation. However, neutralizing antibodies appeared in the plasma of all patients within 12 to 20 days. Thus, the present expression and purification method for recombinant staphylokinase yields large amounts of highly purified mature protein (approximately 200 mg per liter fermentation broth) suitable for a more detailed clinical investigation of its potential as a thrombolytic agent.

Base Sequence↗
PubMed1992

The risk of stroke in patients with acute myocardial infarction after thrombolytic and antithrombotic treatment. Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico II (GISSI-2), and The International Study Group.

BACKGROUND: Many trials in patients with acute myocardial infarction have demonstrated that thrombolytic therapy is not associated with an excessive risk of stroke, as compared with conventional treatment. However, the incidence of various forms of stroke in patients treated with different thrombolytic and antithrombotic regimens and the associated effect of risk factors for stroke are largely unknown. METHODS: Strokes occurring in patients hospitalized with acute myocardial infarction who were enrolled in either of two large trials were analyzed. The patients were randomly assigned to receive streptokinase (1.5 million units) or recombinant tissue plasminogen activator (t-PA) (100 mg) and also randomly assigned to receive subcutaneous heparin or no heparin. Ninety-one percent of the patients also received aspirin. RESULTS: Complete data were available on 20,768 patients. A total of 236 (1.14 percent) had strokes in the hospital; 0.36 percent had hemorrhagic strokes, 0.48 percent ischemic strokes, and 0.30 percent strokes of undefined cause. Patients treated with t-PA had a small but significant excess of stroke as compared with those who received streptokinase (1.33 vs. 0.94 percent; adjusted odds ratio, 1.42; 95 percent confidence interval, 1.09 to 1.84). The administration of subcutaneous heparin in addition to a thrombolytic agent did not increase the risk of stroke (risk with heparin, 1.13 percent; without heparin, 1.14 percent). Older age, a higher Killip class, and the occurrence of anterior infarction significantly increased the risk of stroke, whereas a higher body-mass index or a history of hypertension, diabetes, or smoking did not. CONCLUSIONS: Patients with acute myocardial infarction who receive thrombolytic therapy have a small risk of stroke. Treatment with t-PA as compared with streptokinase resulted in a small but significant excess of stroke. Subcutaneous heparin, given together with t-PA or streptokinase and aspirin, did not result in an increased risk of stroke.

Aged↗
PubMed1992

Present status of rescue coronary angioplasty: current polarization of opinion and randomized trials.

Whereas coronary angioplasty has been demonstrated to be unnecessary and perhaps harmful for most patients after successful thrombolytic treatment of acute myocardial infarction, the clinical benefit of rescue angioplasty after failed thrombolysis remains untested in a randomized clinical trial. However, in the clinical judgment of many physicians it is unethical to withhold such treatment, whereas a nearly equal number of physicians believe that such treatment cannot be justified. A review of reported nonrandomized data from a limited number of patients suggests that 1) coronary angioplasty is successful in only 80% of patients after failed thrombolysis, 2) later reocclusion rates may depend on the thrombolytic agent used, 3) left ventricular ejection fraction is seldom improved, and 4) mortality rates after successful angioplasty approximate those after successful thrombolysis alone but mortality rates after failed angioplasty are remarkably high. The arguments for and against rescue angioplasty are reviewed, and it is concluded that results of randomized trials are needed to replace disparate clinical opinion on whether this potentially costly form of therapy should be widely implemented.

Angioplasty, Balloon, Coronary↗
PubMed1992

Antecedent angina pectoris predicts worse outcome after myocardial infarction in patients receiving thrombolytic therapy: experience gleaned from the International Tissue Plasminogen Activator/Streptokinase Mortality Trial.

The significance of antecedent angina in predicting clinical outcome was assessed in 8,329 patients with acute myocardial infarction who received thrombolytic therapy with either recombinant tissue-type plasminogen activator or streptokinase. There were 2,370 patients with antecedent angina for greater than 1 month, 1,512 patients with antecedent angina for less than or equal to 1 month and 4,447 patients with no antecedent angina. The longer the duration of angina, the worse the baseline characteristics in the three groups: the mean patient age was 65 versus 62 versus 61 years, respectively (p less than 0.0001); the rate of previous myocardial infarction was 37% versus 18% versus 10% (p less than 0.0001); and the rate of hypertension was 40% versus 31% versus 27% (p less than 0.0001). Antecedent angina was associated with a longer hospital stay (11.3 and 11.7 days vs. 10.8 days, p less than 0.0001), a higher incidence of bypass surgery (2.2% vs. 1.2% vs. 0.7%, p = 0.0001), a worse Killip class at discharge (10.6% of patients in class greater than 1 vs. 8.7% vs. 6.4%, p = 0.0001), and a higher hospital and 6-month mortality (12.1% and 18% vs. 8.9% and 11.6% vs. 6.6% and 9.2%, respectively, p less than 0.0001). A multivariate analysis taking into account all baseline characteristics confirmed the independent association of antecedent angina with mortality, with a relative risk of 1.4 to 1.47 (p less than 0.001). Antecedent angina predicts a worse clinical outcome and a more intense use of medical resources in patients with acute myocardial infarction receiving thrombolytic therapy.

Aged↗
PubMed1992

Confronting the issues of patient safety and investigator conflict of interest in an international clinical trial of myocardial reperfusion. Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) Steering Committee.

The Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) trial is a large scale international trial of new myocardial reperfusion strategies. The primary hypothesis is that early and sustained coronary artery recanalization will be associated with a significant reduction in mortality. The four regimens that are being tested are 1) streptokinase with subcutaneous heparin; 2) streptokinase with intravenous heparin; 3) accelerated recombinant tissue-type plasminogen activator (rt-PA) with intravenous heparin; and 4) combination streptokinase, rt-PA and intravenous heparin. The planned recruitment of 41,600 patients in 1,500 sites from 15 countries is expected to be completed by December 1992 and will enable detection of a 15% reduction or 1% absolute difference in mortality compared with that associated with standard therapy (streptokinase and subcutaneous heparin). In designing the trial, two important issues were directly addressed. First, a strategy was developed to provide assurance of patient safety during large scale investigational use of an aggressive thrombolytic regimen. This includes fascimile transmission of a one-page safety summary form to the Data Coordinating Center within 24 h of death or discharge, acceptance of the concept of "net clinical benefit" and close surveillance of the trial's progress by the independent Data and Safety Monitoring Committee. Second, to avoid potential conflict of interest beyond elimination of any position of financial equity, the Steering Committee unanimously voted to prohibit any honoraria for speaking engagements, payment for consultancy or travel or reimbursement of any kind from any of the five corporate sponsors until 1 year after publication of the results. Incorporation of these approaches may facilitate the design of future large scale randomized trials in cardiovascular medicine.

Biomedical Research↗
PubMed1992

A randomized placebo controlled trial on the effects of simvastatin, a HMG-CoA reductase inhibitor, on blood lipids and fibrinolytic parameters.

Coronary artery disease is frequently associated with disturbed blood lipids and with a deficient blood fibrinolytic capacity. In order to investigate a possible link between hypercholesterolemia and hypofibrinolysis, we have investigated the effect of simvastatin, a HMG-CoA reductase inhibitor, on blood lipids and fibrinolytic parameters in a double blind, randomized, placebo controlled study design. Twenty-four male patients, aged between 42 and 65 years, with angiographically confirmed coronary artery disease, were selected from a series of 731 consecutive patients on the basis of a fasting serum cholesterol level of more than 250 mg/dl and a plasma PAI-1 level of more than 60 ng/ml. Patients were randomly assigned to 20 mg of simvastatin daily (Group I), or placebo (Group II), for four weeks, followed by doubling of the dose for another four weeks. Blood samples were obtained at baseline and at 4 and 8 weeks. Groups I and II did not differ significantly at baseline. As expected, simvastatin produced a significant reduction in serum levels of total cholesterol (33 +/- 12 and 36 +/- 12 percent, mean +/- SD, after 4 and 8 weeks respectively, p less than 0.001 vs baseline), LDL-cholesterol (36 +/- 5 and 43 +/- 6 percent respectively, p less than 0.001 vs baseline) and apolipoprotein-B (20 +/- 29 and 23 +/- 30 percent respectively, p less than 0.05 vs baseline), whereas these parameters did not change significantly in the placebo group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

The role of percutaneous transvenous balloon mitral valvuloplasty in the treatment of patients with symptomatic mitral stenosis.

Since its introduction in 1984, percutaneous transvenous mitral balloon valvuloplasty (PTMV) has emerged as an effective technique in the treatment of selected patients with severe mitral stenosis. The most important factors determining the haemodynamic and clinical outcome after PTMV are the anatomic and pathological features of the mitral valve apparatus. In patients with pliable, non-calcified valves, immediate success rates of well over 90% are achieved. Short-term follow-up studies of such patients after PTMV demonstrate a low rate of valve restenosis, with the vast majority of patients remaining much improved clinically. Less favourable immediate and short-term results are observed in patients who have non-pliable, calcified valves. Major acute complications of PTMV include thromboembolic events and the production of severe mitral regurgitation. It appears that, as a result of increased operator experience, better patient selection and refinements in the technique of PTMV, the rates of these acute complications are now very low. Follow-up studies will be needed to assess the long-term efficacy of the procedure. The first publications on this field are encouraging.

Calcinosis↗
PubMed1992

Isolated single coronary artery: a review of 50,000 consecutive coronary angiographies.

Single coronary artery is a rare congenital anomaly of the coronary arteries where only one coronary artery arises from the aortic trunk by a single coronary ostium, supplying the entire heart. A database consisting of the angiographic reports of 50,000 consecutive coronary angiographies performed in adult patients in the University Hospital of Leuven between March 1973 and August 1991 was searched for the diagnosis of single coronary artery. All films concerned were reviewed and classified according to their anatomical type. Thirty-three cases of single coronary artery were retrieved, yielding an incidence of 0.066%. Patient characteristics and clinical data are described, with a discussion on the pathological importance of this finding.

Adult↗
PubMed1992

Effect of early intravenous heparin on coronary patency, infarct size, and bleeding complications after alteplase thrombolysis: results of a randomised double blind European Cooperative Study Group trial.

OBJECTIVE: To determine whether concomitant treatment with intravenous heparin affects coronary patency and outcome in patients treated with alteplase thrombolysis for acute myocardial infarction. DESIGN: Double blind randomised trial. TREATMENT REGIMENS: Alteplase 100 mg (not weight adjusted) plus aspirin (250 mg intravenously followed by 75-125 mg on alternate days) plus heparin (5000 units intravenously followed by 1000 units hourly without dose adjustment) was compared with alteplase plus aspirin plus placebo for heparin. SETTING: 19 cardiac centres in six European countries. SUBJECTS: 652 patients aged 21-70 years with clinical and electrocardiographic features of infarcting myocardium in whom thrombolytic therapy could be started within six hours of the onset of major symptoms. MAIN OUTCOME MEASURE: Angiographic coronary patency 48-120 hours after randomisation. RESULTS: Coronary patency (TIMI grades 2 or 3) was 83.4% in the heparin group and 74.7% in the group given placebo for heparin. The relative risk of an occluded vessel in the heparin treated group was 0.66 (95% confidence interval 0.47 to 0.93). Mortality was the same in both groups. There were non-significant trends towards a smaller enzymatic infarct size and a higher incidence of bleeding complications in the group treated with heparin. CONCLUSIONS: Concomitant intravenous heparin improves coronary patency in patients with alteplase. Whether this can be translated into improved clinical benefit needs to be to be tested in a larger trial.

Adult↗
PubMed1992

Comparative copper coil-induced thrombogenicity of the internal mammary, left anterior descending coronary, and popliteal arteries in dogs.

The internal mammary artery (IMA) is the graft of choice for coronary artery bypass surgery because of its resistance to atherosclerosis. Studies to elucidate the mechanism of this phenomenon have focused on vasoactive properties of the vessel wall; however, low thrombogenicity might also contribute to the protection of the IMA against atherosclerosis. To test this hypothesis, copper coils 3 mm long were introduced in 14 heparinized dogs into both the IMA and the left anterior descending coronary artery (LAD) (n = 7) or into both the IMA and the popliteal artery (POP) (n = 7). Arterial patency was monitored angiographically at 15-minute intervals for 4 hours. Occlusion occurred in all LADs and POPs and in 10 of the 14 IMAs. Spontaneous reflow after occlusion occurred in all IMAs and was followed by cyclic reocclusion and reflow in two animals. Short periods of reflow followed by reocclusion occurred in two of the seven LADs and three of the seven POPs. The patency status, categorized as persistent occlusion, reflow followed by reocclusion, reflow without reocclusion, or persistent patency, was significantly different between IMA and LAD (p less than 0.02) and between IMA and POP (p less than 0.04) but not between LAD and POP. Patent arteries at the end of the 4-hour period were observed in all of the 14 IMAs versus none of the seven LADs and two of the seven POPs (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Angiography↗