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F D Loop

Publications and source records attributed to F D Loop.

At least 55 records · Page 3Linked to original sources

Low factor XIIIA levels are associated with increased blood loss after coronary artery bypass grafting.

Current hematologic approaches to minimize postoperative bleeding have focused principally on antifibrinolytic agents. To explore whether a need might exist to promote clot stabilization independent of steps that might be taken to prevent lysis, we followed levels of the functional A-chain of factor XIII (fibrin stabilizing factor) immunologically in 19 patients undergoing coronary artery bypass grafting. The levels of factor XIIIA together with alterations in fibrinogen were followed at five stages of operation: (1) initial catheter placement (control), (2) heparinization, (3) initiation of cardiopulmonary bypass, (4) discontinuation of cardiopulmonary bypass, and (5) heparin neutralization with protamine sulfate. Significant (p < 0.05) inverse correlations were observed between postoperative chest-tube drainage volumes and levels of XIIIA at stages 1 through 3, and borderline associations (p < 0.1) were observed for stages 4 and 5. Pronounced losses of factor XIIIA accompanied initiation of cardiopulmonary bypass, when levels fell to 43% +/- 12% (standard deviation) of the control value, significantly below the 59% +/- 9% of the control value expected from hemodilution. By comparison, fibrinogen concentrations fell only to the extent attributable to hemodilution, unaccompanied by substantial degradation as indicated by electrophoretic, functional, and immunologic assays. There was a reversible heparin-induced precipitation of fibrin complexes and fibrinogen dimers from the blood on initiation of hypothermia, but these components returned to the circulation on restoration of normothermia. This precipitation was unrelated to losses of factor XIIIA. The findings warrant inference that XIIIA supplementation in deficient states should be considered as an adjunct to other therapies for postoperative bleeding.

Adult↗

Primary isolated coronary artery bypass in left ventricular dysfunction: survival and predictors of survival.

Coronary angiograms of 462 patients with ejection fractions below 51% who underwent primary isolated coronary artery bypass at the Cleveland Clinic from 1981 to 1985 were available for review. They were divided into two groups: group 1 (n = 166) with severe ventricular dysfunction (ejection fraction less than 30%) and group 2 (n = 296) with moderate ventricular dysfunction (ejection fraction 31 to 50%) at a median follow-up of 5.8 years/patient. The actuarial survival was 64.3% in group 1 and 80.6% in group 2 (P = 0.0001). By multivariate analysis, congestive heart failure (P = 0.0001) was the single most important factor affecting survival for both groups. In addition, in group 1 the preoperative use of inotropes (P = 0.03) and in group 2 the presence of peripheral vascular disease (P = 0.001) affected long term survival.

Actuarial Analysis↗

Gastroepiploic and inferior epigastric arteries for coronary artery bypass. Early results and evolving applications.

BACKGROUND: Internal thoracic artery (ITA) conduits are known to provide long-term patency and increased patient survival with low morbidity after coronary artery bypass grafting (CABG). Excellent clinical results with the ITA have stimulated interest in additional arterial grafts. METHODS AND RESULTS: To review our experience and evaluate postoperative complications associated with these new conduits, from May 1985 to September 1993, we studied 290 patients who underwent CABG using additional arterial conduits. The right gastroepiploic artery (GEA) was used in 152 patients and the inferior epigastric artery (IEA) was used in 130 patients. Eight patients with both GEA and IEA grafts were excluded. Patient records were analyzed as to preoperative characteristics, angiographic findings, operative data, and postoperative complications. Statistical analysis was done using the Pearson chi 2 statistic and the t test. Ninety-eight percent of patients received one concomitant ITA graft, and the majority of patients in both groups had bilateral ITA grafts. The GEA group had a higher proportion of reoperations (GEA group, 54%; IEA group, 16%; P < .001), previous myocardial infarction (MI) (GEA group, 67%; IEA group, 50%; P = .004) and New York Heart Association class IV (GEA group, 28%; IEA group, 6%; P = .001). The IEA group was generally slightly older (IEA group, 56 years; GEA group, 52 years; P = .001). Hospital mortality (GEA group, 4%; IEA group, 0.8%) and postoperative morbidity (mediastinal bleeding, infection, stroke, MI, and low cardiac output) were not significantly different between the two groups or from our experience with routine CABG using the ITA. Three intraabdominal complications occurred in the GEA group: 2 episodes of bleeding and 1 of pancreatitis. One patient in the IEA group had abdominal wall bleeding. With overall short follow-up, angiographic patency in a small number of patients has been good: 80% for the GEA group and 85.7% for the IEA group. CONCLUSIONS: We conclude that the morbidity associated with these additional arterial conduits is low and is comparable with that associated with routine CABG using the ITA. Currently we use the ITA for primary targets and alternative arterial conduits for vessels of secondary importance or when the ITA and/or saphenous vein is not available.

Abdominal Muscles↗

The value and conduct of reoperations for coronary atherosclerosis.

The best advice for the referring physician is to find a surgical team skilled and experienced in the treatment of reoperation patients. The cardiologist and surgeon should select patients carefully, prevent complications by good technique and management, and use internal thoracic arteries whenever feasible. The reoperation must be planned and conducted precisely. Coronary artery reoperations are extensive procedures, and patients should be fully informed of the benefits and risks. Experience has resulted in fewer technical accidents today, more complete revascularization, greater use of arterial grafts, and improvements in blood conservation and myocardial protection. As a consequence, the operation is safer, and under proper conditions, stands to afford greater and longer benefit.

Coronary Artery Bypass↗

Surgical treatment of isolated left anterior descending coronary stenosis. Comparison of left internal mammary artery and venous autograft at 18 to 20 years of follow-up.

To assess the long-term results of the surgical treatment of isolated left anterior descending coronary artery stenosis and compare surgical strategies for graft selection, we reviewed 100 consecutive patients receiving left internal mammary artery-to-left anterior descending artery grafts and 100 consecutive patients who received a saphenous vein autograft to the left anterior descending artery. All patients underwent operation from 1971 through 1973. The internal mammary artery and saphenous vein graft groups were equivalent with regard to preoperative clinical and angiographic variables, except that patients receiving left internal mammary artery grafts had a higher prevalence of noncritical disease (less than 50% stenosis) in the circumflex and right coronary arteries than did the saphenous vein graft group. Mean follow-up for the internal mammary artery and saphenous vein graft groups was 18.7 years and 20.7 years, respectively. The 18-year outcome was superior for the internal mammary artery group. Cox regression analysis confirmed that patients with left internal mammary artery grafts had superior survival, intervention-free survival, and event-free survival (all p < 0.01). The presence of noncritical disease in other vessels adversely affected intervention-free survival and event-free survival for both groups (all p < 0.03) and decreased survival for the saphenous vein graft group (p = 0.01) but not for the internal mammary artery group (p = 0.24). We conclude that in long-term follow-up of surgically treated isolated left anterior descending artery stenosis (1) the left internal mammary artery consistently yields better overall and intervention-free survival than does the saphenous vein graft, (2) outcome is influenced by the presence of noncritical disease in other vessels at the initial operation, and (3) deployment of the left internal mammary artery in the treatment of isolated left anterior descending artery stenosis yielded 18 years of intervention-free survival of 60.5% and provides a standard for comparison with other forms of therapeutic intervention.

Coronary Angiography↗

Influence of arterial coronary bypass grafts on the mortality in coronary reoperations.

From 1988 through 1991, 1663 patients underwent a first reoperation for isolated coronary bypass grafting with 62 (3.7%) in-hospital deaths. At the primary operation, 575 patients had received at least one internal thoracic artery graft and 489 patients had at least one patent internal thoracic artery graft present at the time of reoperation. At reoperation, 1014 patients received at least one internal thoracic artery graft, 10 received an inferior epigastric graft, and 37 received a gastroepiploic graft. Of 489 patients with patent internal thoracic artery grafts at reoperation, the internal thoracic artery was damaged in 17 (3.5%); of 428 patients with a patent internal thoracic artery graft to the left anterior descending coronary artery, 14 (3.3%) had graft damage necessitating regrafting. All patients with damaged internal thoracic arteries survived. Multivariate testing of variables for their association with in-hospital mortality identified no internal thoracic artery graft at either primary surgery or reoperation (p < 0.0001), a history of congestive heart failure (p < 0.0001), advancing age (p = 0.018), female gender (p = 0.029), and emergency operation (p = 0.01) as factors linked to increased risk. Left ventricular function, left main stenosis, extent of native coronary atherosclerosis, and the interval between operations did not influence mortality. Furthermore, the presence of an atherosclerotic vein graft to the left anterior descending coronary artery a factor shown to increase in-hospital risk in previous studies did not increase risk during these years. We attribute the observation that patent internal thoracic artery and atherosclerotic vein grafts do not appear to be factors specifically increasing the risk of reoperation to the use of retrograde cardioplegic solution and increased surgical experience. The use of internal thoracic artery grafts at a primary operation does not increase the risk of a reoperation, and the use of internal thoracic artery grafts at reoperation does not increase in-hospital morbidity or mortality.

Age Factors↗

Rehospitalizations after coronary revascularization among Medicare beneficiaries.

The rehospitalization experience of Medicare beneficiaries undergoing coronary artery bypass surgery or percutaneous transluminal coronary angioplasty in 1986 and 1987 was studied by following 53,715 patients who underwent coronary artery bypass and 28,817 patients who underwent angioplasty for 1 year using Medicare hospital claims data. The 1-year rehospitalization rate after bypass and angioplasty was 629 and 863 per 1,000, respectively, compared to a rate of 607 for the Medicare patient population in general. About 45% of rehospitalizations after bypass and two thirds after angioplasty were in categories determined by an expert panel to be possibly related to the original procedure. After angioplasty, there were 61 discharges per 1,000 for bypass surgery and 140 per 1,000 for a repeat angioplasty. Rehospitalization rates for coronary artery bypass surgery after angioplasty were significantly lower for female and black patients who underwent angioplasty. The volume of rehospitalization after revascularizations makes it an important outcome measure. Medicare administrative records provide a unique source of information on rehospitalizations and make possible the monitoring of broad trends in the frequency and outcomes of coronary revascularization. The lower rates of bypass surgery after angioplasty for black and female patients are in line with other studies and bear further investigation.

Aged↗

Analysis of coronary angioplasty practice in the United States with an insurance-claims data base.

BACKGROUND: Coronary angioplasty is frequently performed in the United States, with more than 300,000 procedures in 1990. Despite the high rate of use of the procedure, there have been few studies addressing practice patterns. METHODS AND RESULTS: From a private insurance claims data base of 5.4 million individuals, a total of 2,101 patients who underwent coronary angioplasty during 1988-1989 were identified. Using their 4,578 hospital admission records and 87,578 outpatient claim records, with an average follow-up of 332 +/- 182 days, we compared patients' outcomes and charges according to whether they had an exercise stress test before the procedure, by sex, by region of the country, and by whether the angioplasty was performed in an institution with a training program. Only 29% of the study cohort had exercise testing before angioplasty; patients in the West (p = 0.001), those undergoing multivessel angioplasty (p = 0.00001), and those whose procedures were performed at sites with training programs (p = 0.04) were more likely to have a screening test, whereas women (p = 0.008) and those with a recent myocardial infarction (p = 0.00001) were less likely to have a screening test. The average length of stay for patients without myocardial infarction as a primary diagnosis was 5.6 days, with a total hospital charge of $15,027. In follow-up, 15.1% had coronary artery bypass surgery and 15% had at least one additional angioplasty procedure; the average follow-up charges were $4,879. Charges varied according to sex, region of the country, and academic status of the angioplasty institution. Certain outcomes showed variation by region of the country and academic status of the angioplasty institution. CONCLUSIONS: The relative lack of an objective definition of myocardial ischemia and the marked variability of use of procedures according to geographic region suggest the need for further implementation of established guidelines.

Age Factors↗

The effect of coronary reoperation on the survival of patients with stenoses in saphenous vein bypass grafts to coronary arteries.

Does coronary artery reoperation improve the survival of patients with stenoses in saphenous vein bypass grafts to coronary arteries? To examine this question, we retrospectively reviewed 1117 patients who had coronary bypass grafting and then underwent a postoperative coronary angiogram that showed a stenosis (> or = 20%) of at least one vein graft. Reoperation within 1 month of the postoperative angiogram was performed for 394 patients (REOP group) whereas 723 patients (MED group) received initial medical treatment (no reoperation or percutaneous transluminal coronary angioplasty within 1 year). Compared with the MED group, patients in the REOP group were older, more symptomatic, more likely to have left main stenosis, and had fewer patent bypass grafts (all p < 0.001). In-hospital mortality for the REOP group was 4.3%. Mean postangiogram follow-up of the entire group was 73 months. On the basis of the interval between the primary operation and the postoperative angiogram, patients were designated as having early (< 5 years) or late (> or = 5 years) saphenous vein graft stenosis. Univariate and multivariate analyses were used to identify factors influencing the survival of these subgroups. Reoperation was not identified as a variable improving the survival of patients with early vein graft stenoses. For patients with late vein graft stenoses, moderate or severe impairment of left ventricular function (p < 0.0001), advanced age (p < 0.0001), triple-vessel or left main stenosis (p = 0.0011), and stenosis in a vein graft to the left anterior descending artery (p = 0.0019) decreased survival, whereas reoperation improved survival (p = 0.0007). The improvement in survival with reoperation was particularly strong for patients with a stenotic vein graft to the left anterior descending artery. For that subset, survival was 84% and 74% for the REOP group versus 76% and 53% for the MED group at 2 and 4 years after catheterization, respectively (p = 0.004). For patients with stenotic vein grafts to the right coronary artery or circumflex coronary artery (or both), survival was 92% and 87% for the REOP group versus 89% and 78% for the MED group at 2 and 4 years after catheterization, respectively (p = 0.13). Even for patients with class I or II symptoms, reoperation prolonged survival (p = 0.002 with multivariate testing). Reoperation improves the survival of patients with late vein graft stenoses, particularly those with stenotic grafts to the left anterior descending coronary artery.

Constriction, Pathologic↗

Stratification of morbidity and mortality outcome by preoperative risk factors in coronary artery bypass patients. A clinical severity score.

OBJECTIVE: To relate morbidity and mortality risk to preoperative severity of illness in patients undergoing coronary artery bypass grafting. DESIGN: Retrospective analysis of 5051 patients using univariate and logistic regression to identify risk factors associated with perioperative morbidity and mortality. Prospective application of models to a subsequent 2-year validation cohort (n = 4069). SETTING: Cleveland Clinic Foundation. PATIENTS: All adult patients undergoing coronary artery bypass graft surgery between July 1, 1986, and June 30, 1988 (reference group), and July 1, 1988, and June 30, 1990 (validation group). MAIN OUTCOME MEASURES: Mortality and morbidity (myocardial infarction and use of intra-aortic balloon pump, mechanical ventilation for 3 or more days, neurological deficit, oliguric or anuric renal failure, or serious infection). MAIN RESULTS: Emergency procedure, preoperative serum creatinine levels of greater than 168 mumol/L, severe left ventricular dysfunction, preoperative hematocrit of 0.34, increasing age, chronic pulmonary disease, prior vascular surgery, reoperation, and mitral valve insufficiency were found to be predictive of mortality. In addition to these factors, diabetes mellitus, body weight of 65 kg or less [corrected], aortic stenosis, and cerebrovascular disease were predictive of morbidity. Logistic regression equations were developed, and a simple additive score for clinical use was designed by allocating each of these risk-factor values of 1 to 6 points. Both methods predict mortality. Increased morbidity was demonstrated with increases in score. CONCLUSIONS: The logistic or clinical models developed are superior to the currently available methods for comparing mortality outcome and provide previously unavailable information on morbidity based on preoperative status. The clinical scoring system is useful for preoperative estimates of morbidity and mortality risks.

Aged↗

Role of prophylactic anticoagulation for direct current cardioversion in patients with atrial fibrillation or atrial flutter.

The need for prophylactic anticoagulation to prevent embolism before direct current cardioversion is performed for atrial fibrillation or atrial flutter is controversial. To examine this issue further, a retrospective review was undertaken to assess the incidence of embolic complications after cardioversion. The review involved 454 elective direct current cardioversions performed for atrial fibrillation or atrial flutter over a 7 year period. The incidence rate of embolic complications was 1.32% (six patients); the complications ranged from minor visual disturbances to a fatal cerebrovascular event. All six patients had atrial fibrillation, and none had been on anticoagulant therapy (p = 0.026). The duration of atrial fibrillation was less than 1 week in five of the six patients who had embolic complications. Baseline characteristics of patients with a postcardioversion embolic event are compared with those of patients who did not have an embolic event. There was no difference in the prevalence of hypertension, diabetes mellitus or prior stroke between the two groups, and there was no difference in the number of patients who were postoperative or had poor left ventricular function. Left atrial size was similar between the two groups. No patient in the embolic group had valvular disease. No patient with atrial flutter had an embolic event regardless of anticoagulant status; therefore, anticoagulation is not recommended for patients with atrial flutter undergoing cardioversion. Prophylactic anticoagulation is pivotal in patients undergoing elective direct current cardioversion for atrial fibrillation, even those with atrial fibrillation of less than 1 week's duration.

Anticoagulants↗

Aprotinin therapy for reoperative myocardial revascularization: a placebo-controlled study.

We tested the efficacy and safety of aprotinin in 169 patients undergoing isolated reoperative myocardial revascularization. Patients were randomly assigned to high-dose aprotinin, low-dose aprotinin, or placebo treatment groups in a double-blind, placebo-controlled study. Treatment groups did not differ significantly with respect to age, sex, red cell mass, number of grafts, use of internal thoracic artery, or incidence of preoperative aspirin therapy. Patients treated with aprotinin had a significant reduction in postoperative chest tube drainage (720 +/- 753, 866 +/- 1,636, and 1,121 +/- 683 mL, respectively, for high-dose aprotinin, low-dose aprotinin, and placebo; p < 0.001). Transfusion requirements were reduced in aprotinin-treated patients (2.1 +/- 4.2, 4.8 +/- 11.8, and 4.1 +/- 6.2 units for high-dose, low-dose, and placebo, respectively; p < 0.001). A similar reduction in chest tube drainage and transfusion requirements was seen in patients using aspirin preoperatively. Q-wave myocardial infarctions were increased in the aprotinin subgroups (17.5%, 14.3%, and 8.9% for high-dose, low-dose, and placebo groups; not significant). Acute vein graft thrombosis was found in six of 12 vein grafts studied at postmortem examination in patients receiving aprotinin but not in any of five grafts in patients receiving placebo. We conclude that aprotinin is extremely effective in reducing bleeding and transfusion requirements and may increase the risk of graft thrombosis.

Aged↗

Postcardiotomy centrifugal mechanical ventricular support.

From August 1979 through August 1991, 91 patients were supported with centrifugal mechanical ventricular assist. Major indications for its use were postcardiotomy ventricular failure (79) or as a bridge to cardiac transplantation (12). In postcardiotomy use (0.2% of all cardiac procedures), there were 54 male (68.4%) and 25 female patients (31.6%) with a mean age of 54.8 years and a mean duration of use of 3.56 days (range, 1 hour to 19 days). Forty-nine patients (62%) were successfully weaned, and 20 (25.3%) were hospital survivors. In 57 patients the device was inserted to wean from cardiopulmonary bypass, whereas in 22 it was employed later in the postoperative period because of low cardiac output or sudden arrest. Thirty-four (59.6%) of the 57 patients in the former group were weaned, and 15 (26.3%) were discharged, results similar to those in the latter group with 15 (68.2%) weaned and 5 (22.7%) discharged. Morbidity associated with use of centrifugal blood pumps included bleeding (87.3%; mean transfusion requirement, 53.2 units), renal failure (46.8%), cerebrovascular accident (12.7%), thromboembolism (12.7%), and hepatic insufficiency (12.7%). After a mean follow-up of 45.4 months (range, 2 to 142 months), 7 patients had died (35% late mortality), 1 patient is in functional class IV, and all others are in functional class I or II. Lower survival was associated with biventricular failure and renal failure but not with age or sex of the patient.

Age Factors↗