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Biomedical subjects

L Campeau

Publications and source records attributed to L Campeau.

At least 55 records · Page 3Linked to original sources
PubMed1985

Long-term fate of bypass grafts: the Coronary Artery Surgery Study (CASS) and Montreal Heart Institute experiences.

Both the Veterans Administration Cooperative Study and the European Coronary Surgery Study have provided only brief accounts of graft patency rates in their surgically treated patients. In the Veterans Administration Cooperative Study, at an average of 1 year after operation, 69% of the grafts were patent among 208 patients; 88% of patients had at least one patent graft, and 58% had all grafts patent. In the European Coronary Surgery Study, angiographic examination of the grafts was performed within 9 months of operation in 84 patients, and showed a patency rate of 90%; in 223 patients, the examination was performed at between 9 and 18 months, and showed a 77% patency rate. In the Coronary Artery Surgery Study (CASS), graft patency rates were evaluated within 60 days of operation in 129 patients, a median of 18 months after operation in 121 patients, and a median of 5 years after operation in 197 patients. Cumulative vein graft patency (per distal anastomosis) was 90% early, 82% at 18 months, and 82% at 5 years. At least one graft anastomosis was patent early in 97% of patients, at 18 months in 96% of patients, and at 5 years in 97% of patients; all graft anastomoses were patent early in 81% of patients, at 18 months in 70% of patients, and at 5 years in 67% of patients. The incidence of vein graft stenosis of 50% or more was 10% at 18 months and 8% at 5 years after operation. The excellent results reported in CASS were associated with marked improvement in quality of life and excellent survival 5 years after operation in surgically treated patients, as previously reported.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

The relation of risk factors to the development of atherosclerosis in saphenous-vein bypass grafts and the progression of disease in the native circulation. A study 10 years after aortocoronary bypass surgery.

We examined 82 patients 10 years after saphenous-vein aortocoronary bypass surgery to determine their angiographic status and to relate those findings to the risk factors for coronary-artery disease. Of 132 grafts shown to be patent 1 year after surgery, only 50 were unaffected at 10 years. The remainder were narrowed (43) or occluded (39). Disease progression in coronary arteries without grafts was also frequent, both in vessels that were normal (15 of 32) and in those with minor stenosis (25 of 53). New lesions did not develop in 15 patients, whereas they did in 67--in the grafts, the native vessels, or both. There was no significant difference between the two groups in the incidence of hypertension, diabetes, or smoking, whereas plasma levels of very-low-density lipoproteins (VLDLs) and low-density lipoproteins (LDLs) were higher, and high-density lipoprotein (HDL) levels were lower in those with new disease than in those without. Univariate analysis showed that plasma cholesterol and triglyceride levels were significantly higher at the time of surgery and at the 10-year examination in those with new lesions. Multivariate analysis indicated that among the lipoprotein indexes, levels of HDL cholesterol and plasma LDL apoprotein B best distinguished the two groups. The findings indicate that atherosclerosis in these patients was a progressive disease, frequently affecting both the grafts and the native vessels, and that the course of such disease may be related to the plasma lipoprotein levels.

Cholesterol↗
PubMed1984

Progression of atherosclerosis in coronary arteries and bypass grafts: ten years later.

Progression of atherosclerosis in aortocoronary saphenous vein grafts is frequent and is the predominant cause of late graft closure after CABG. Only approximately 60% of grafts remain patent between 10 and 12 years after surgery. Of patent grafts, 45% show angiographic evidence of atherosclerosis between 10 and 12 years after surgery and 70% of the atherosclerotic lesions reduce the graft lumen diameter by 50% or more. Atherosclerosis of saphenous vein grafts does not appear to be related to age, sex or cigarette smoking, but is associated with abnormalities of cholesterol lipoprotein fractions. Progression of atherosclerosis in the native coronary arteries is also very significant after CABG. Progression of CAD between 10 and 12 years after surgery occurs in approximately 50% of nongrafted arteries. Between 10 and 12 years after surgery, the rate of progression of disease in nongrafted arteries is not different from that of grafted arteries with patent grafts; however, progression is more frequent in grafted arteries with occluded grafts. The rate of progression is not related to age, sex, risk factors or extent of disease at baseline coronary arteriography. Progression of preexisting stenoses is more frequent than appearance of new stenosis. Progression is related to the severity of the preexisting stenosis only in nongrafted arteries. Finally, progression is related to alterations of left ventricular function during follow-up. Because of these progressive late changes, CABG should probably remain limited to patients with incapacitating anginal symptoms or to those with severe lesions for whom surgery might enhance long-term survival, such as patients with severe left main CAD and 3-vessel CAD.

Adult↗
PubMed1984

Myocardial infarction in patients with previous coronary artery bypass surgery.

An increasing proportion of patients hospitalized with myocardial infarction have previously undergone coronary artery bypass surgery. To define this subgroup, 77 patients with acute infarction occurring 2 or more months (mean 52.8) after bypass surgery were compared with 77 control patients with infarction. Baseline characteristics of the groups were similar except that post-bypass patients were more often men (p = 0.02) and more likely to have had a previous infarction (37 versus 21, p = 0.008). Infarct size was smaller in the post-bypass group as assessed by peak creatine kinase (CK), peak CK-MB, maximal number of electrocardiographic leads with ST elevation, maximal summed ST elevation and QRS score measured 7 to 10 days after admission (p less than 0.001 for each variable). Five control patients but none of the post-bypass patients died in the hospital (p = 0.06). Serious complications (death, acute heart failure, ventricular fibrillation, second or third degree atrioventricular block) occurred in 24 control patients but in only 5 post-bypass patients (p less than 0.001). Angiography was performed after infarction in 45 of the 77 post-bypass patients. Occlusion of both a native coronary artery and its graft was found in 24 of the 45; these patients had had higher peak CK levels (p = 0.008) than the other 21 patients who had angiography. The probable causes of infarction in these 21 were disease progression in nonbypassed arteries or graft occlusion with arterial stenosis, or vice versa, and disease progression distal to a patent graft.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Partial ileal bypass in type II familial hypercholesterolemia. Eleven-year experience at the Montreal Heart institute.

The National Heart, Lung, and Blood Institute is currently sponsoring a multicenter clinical trial to evaluate the long-term efficacy of partial ileal bypass in the prevention of recurrent myocardial infarction in hypercholesterolemia patients. Thus we felt that a report of our clinical results with this intervention at the Montreal Heart Institute during the last 11 years would be of interest. Twenty patients with type II hyperlipoproteinemia and a mean age of 38 (range 25-54) years underwent partial ileal bypass between March 1971 and April 1978. This intervention was associated with aortocoronary bypass surgery in 11 patients. All patients were followed at regular intervals. The mean survival time was 70.7 (range 1-123) months. Two deaths were observed during follow-up, one from an acute myocardial infarction and the other from ventricular fibrillation, respectively, 1 month and 1 and one-half years after partial ileal bypass. The ileal bypass was undone twice because of gastrointestinal problems including a malabsorption syndrome and repeated episodes of subocclusion. A progressive decrease of the effects of the operation on serum cholesterol was noted, from a 33 per cent reduction at 3 months to 43 per cent at 2 years and 16 per cent at 6 years. Two patients presented an acute myocardial infarction respectively 3 and 4 years after the operation, respectively, and one patient suffered a right-sided hemiplegia at age 30, 12 months after the operation. Of 14 patients with angina pectoris preoperatively (class III in 10), eight remained symptomatic postoperatively (class I and II angina in five).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Reoperation in patients with patent atherosclerotic coronary vein grafts. A different approach to a different disease.

Atherosclerotic changes are often noted in vein grafts at angiography 8 to 10 years after coronary artery grafting. Reoperation in these patients is hazardous, as manipulation of the grafts may loosen atheromatous debris and cause coronary embolization and myocardial infarction. A technique is described to avoid embolization of atheromatous material during reoperation in patients with patent atherosclerotic coronary vein grafts. This technique was carried out in six patients and compared to the standard technique of reoperation in similar patients. The incidence of complicated perioperative myocardial infarction (0/6 versus 5/12) and perioperative death (zero versus three) was lower when our new technique was used. This approach consists of minimal dissection for access to the right atrium and ascending aorta for cannulation, prompt ligation of all patent grafts at the start of cardiopulmonary bypass, cardioplegic infusion through the ascending aorta and subsequently also through newly inserted grafts using larger infusions until myocardial temperatures reach less than or equal to 15 degrees C, and single aortic clamping for distal and proximal anastomoses.

Aged↗
PubMed1984

Comparison of late changes in internal mammary artery and saphenous vein grafts in two consecutive series of patients 10 years after operation.

Postoperative angiographic studies were carried out at 1 month, 1 year, and 10 years in two groups of patients: 238 patients with saphenous vein (SV) grafts and 40 patients with internal mammary artery (IMA) grafts. Cumulative patency was better in IMA grafts, both at 1 year (88.5% vs 76.4%) and at 10 years (84.1% vs 52.8%). Atheromatous changes in patent grafts at 10 years were frequent in SV grafts (29/66 or 43.9%) and uncommon in IMA grafts (1/19 or 5.2%; p less than .02). Attrition rate (11.8%) during the first year in IMA grafts (representing our initial experience with IMA grafts) was comparable to that of SV grafts (15.2%) in a group of patients operated on after 2 years of experience. Therefore, early attrition rate may be related to both experience and type of conduit. Later, at 10 years, the conduit itself appears to be the dominant factor. Furthermore, patients who received IMA grafts had a better survival rate at 10 years (84.3% vs 70%) than those who underwent SV bypass grafting.

Arteriosclerosis↗
PubMed1983

Atherosclerosis and late closure of aortocoronary saphenous vein grafts: sequential angiographic studies at 2 weeks, 1 year, 5 to 7 years, and 10 to 12 years after surgery.

Sequential control angiographic examinations were performed at 2 weeks, 1 year, 5 to 7 years, and 10 to 12 years after aortocoronary saphenous vein bypass surgery in 82 unselected patients. Graft modifications consisting of wall irregularities and obstructive lesions of various severity and shapes that were found to develop after the first year were attributed to atherosclerosis. The incidence of these late changes increased from 16% during the interval between 1 year and 5 to 7 years to 36.4% during the subsequent interval between 7 and 12 years (p less than .01). These changes were not influenced by the severity of early diffuse or localized intimal hyperplasia. They were not related to classical risk factors except for low-density lipoprotein and low-density beta-lipoprotein cholesterol. Graft closure increased 2.5-fold from the interval between 1 year and 5 to 7 years to the following period between 7 and 12 years, 10.2% to 26.1% (p less than .02); thus the mean yearly attrition rate augmented from 2% to 5.3%. Late graft closure may result from early localized stenosis most likely related to improper surgical techniques, but the most frequent cause appears to be atherosclerosis. Graft patency at 10 to 12 years is 63.3%.

Adult↗
PubMed1982

Changes in grafts and coronary arteries after saphenous vein aortocoronary bypass surgery: results at repeat angiography.

We studied the patency of saphenous vein aortocoronary bypass grafts in nonconsecutive and consecutive subgroups of our first 600 patients. The patency rates were 87-93% within 1 month and 74-85% approximately 1 year after surgery. The attrition rate of grafts averaged 2.2% per year between 1 and 6 years. Early occlusion was due to thrombosis; occlusion at 1 year was caused by fibrous intimal proliferation of grafts, which also led to variable reduction in caliber and to significant (greater than 50%) segmental stenoses in 5-15% of patent grafts. The most important determinant of graft patency at 1 year was the runoff capacity of the recipient arteries, followed by the quality of the surgical techniques. Late occlusion was related to atherosclerosis that became manifest only after at least 2 years. Coronary atherosclerosis progressed in more than 50% of proximal segments of grafted arteries during the first year, but little additional deterioration occurred between 1 and 6 years. During the first year, only 10% of preexisting stenoses in nongrafted arteries showed progression of disease; progression in these vessels increased to 46% at 6 years and was no longer different, for preexisting lesions greater than 50%, from that of grafted arteries. A close correlation was observed between changes in grafts and in coronary arteries and long-term survival or relief of angina. Ninety-four percent of patients with all grafts patent and 98% with an optimal correction were alive at 6 years compared with 70% of patients without patent grafts or surgical correction. Changes in grafts or coronary arteries were observed in two-thirds of patients in whom functional deterioration occurred between 1 and 6 years, compared with 18% in whom improvement persisted after surgery.

Angiography↗
PubMed1980

Platelet regeneration time and late occlusion of aortocoronary saphenous vein bypass grafts.

The half-time for platelet regeneration was estimated in 16 patients with aortocoronary vein grafts by the use of a non-radioisotopic technique based on the permanent inhibition by acetylsalicylic acid of lipid peroxidation by platelets. Ten patients had patent grafts after 6 years; in the other six at least one graft had become occluded between 2 and 6 years after the operation as shown by serial angiography. The mean half-time (+/- the standard error) for platelet regeneration was reduced to 2.5 +/- 0.2 days (P less than 0.002) in the group with occluded grafts as compared with 3.3 +/- 11 healthy volunteers. These results suggest a relation between late graft occlusion and platelet turnover and support the idea that patients with aortocoronary vein grafts could benefit from platelet suppressive therapy. Finally, the method employed appears to be a useful and simple way of evaluating platelet function in vivo.

Adult↗
PubMed1979

Prophylactic coronary artery grafting in patients with few or no symptoms.

Fifty-five patients who underwent prophylactic coronary artery grafting were followed for 4 to 8 years. Sixteen patients had no angina, and 39 were in New York Heart Association Functional Class I. Twenty-one patients had single-vessel disease, 13 had double-vessel disease, and 27, triple-vessel disease. A total of 101 grafts were inserted. There were no operative deaths. Two patients suffered a perioperative myocardial infarction (MI), and 3 were reoperated on for persistent bleeding. Early after operation, 9 of the 45 grafts were occluded. At 1 year, 2 patients had occlusion of all grafts, and 1 had similar findings at 5 years. There were 4 late deaths, 3 related to coronary artery disease. Seven patients sustained a late MI. Thirty-one of the 51 survivors (60.8%) seen late (mean, 69.3 months) after operation were free from angina; 14 were in Class I and 6, Class II. It is apparent from this retrospective study that patients such as these stand to benefit little from prophylactic revascularization. Longevity may be increased, however, in patients who are asymptomatic after MI.

Adult↗
PubMed1979

Loss of the improvement of angina between 1 and 7 years after aortocoronary bypass surgery: correlations with changes in vein grafts and in coronary arteries.

Improvement of effort angina following pure aortocoronary bypass graft surgery was related to postoperative control angiographic studies of grafts and coronary arteries in 75 unselected patients. Clinical and angiographic evaluations were carried out at approximately 1 year and at 5 to 7 years after surgery. At 1 year, 61 (81.3%) were improved (52 without angina and 9 with partial improvement by at least two functional classes), whereas 14 were unimproved (18.7%). At approximately 6 years, loss of improvement (reappearance of angina or aggravation by at least two functional classes) was observed in 22 of the 61 improved patients, representing an attrition of 36.1% over a 5-year period. Graft occlusion or a narrowing of over 50% was observed in two of the 39 patients in whom improvement had continued (5.1%), whereas it was found in six of the 22 patients (27.3%) whose results deteriorated (p less than 0.05). Similarly, progression to occlusion of a preexisting stenosis of over 50% or appearance of a new stenosis of over 50% in a major coronary artery (distal to a graft or in an unbypassed artery) was observed in five of the 39 patients with continued improvement (12.8%) and in 11 of the 22 patients whose condition deteriorated (p less than 0.01). Changes in a graft or in a coronary artery were noted in 63.6% (14/22) of the patients with loss of improvement as compared to only 18% (7/39) of the patients whose improvement did not deteriorate. Improvement of angina was also evaluated in all survivors among our first 500 cases who had preoperative effort angina and pure bypass surgery with or without angiographic studies. Of these 260 patients, 70.4% were angina-free or improved by two to three functional classes at 1 year, and only 41.9% at 7 years after surgery. It is concluded that the effect of aortocoronary bypass graft surgery is transient in a high proportion of patients and that deterioration of results is related to late graft modifications and progression of atherosclerosis, particularly in ungrafted coronary arteries.

Adult↗
PubMed1979

Clinical and angiographic determinants of early mortality related to aortocoronary bypass surgery.

Clinical and angiographic features were identified that influences early mortality in 807 patients who underwent aortocoronary bypass grafting alone among the first 1000 consecutive patients subjected to aortocoronary bypass operations at the Montreal Heart Institute. The early mortality was 4.7% and was related to the patient's age, the duration of the illness from its first clinical manifestation, certain types of clinical presentation, electrocardiographic findings, the number of obstructed arteries and the ejection fraction. The influence of the number of obstructed arteries appeared to be independent of other factors, including the number of grafts and the degree of correction. Early mortality was not influenced by risk factors such as lipid abnormalities, hypertension or diabetes, by the history of previous myocardial infarction or the number of grafts.

Adult↗