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F D Loop

Publications and source records attributed to F D Loop.

At least 37 records · Page 2Linked to original sources
PubMed1997

Third coronary artery bypass operations: risks and costs.

BACKGROUND: Third coronary artery bypass operations are technically difficult and are associated with increased risk. METHODS: We reviewed the cases of 469 patients who had undergone a third isolated coronary artery bypass operation and used univariate and multivariate testing to examine the effect of preoperative and operative variables on outcome and costs. RESULTS: The in-hospital mortality was 7.0% (33 patients). Advanced age and severe symptoms were found to increase risk (both p < 0.05): the mortality was 14% (n = 74) in patients 70 years old or older who had severe symptoms. However, the overall mortality for 1993 through 1995 was 4.3% (5/117) and only one death (1.3%) occurred among the 79 patients who were less than 70 years old. The late survival rate was 94%, 84%, and 66% at 1, 5, and 10 postoperative years, respectively, and predictors of decreased late survival were advanced age, abnormal left ventricular function, and diabetes (all p < 0.05). Again, age of 70 years or more was a predictor of a poor outcome. Only 52% of patients in that subgroup (including both early and late mortality) were alive 5 years after operation. Analysis of direct hospital costs showed that the mean costs of third coronary artery bypass operations were 21% higher than the mean costs of primary operations but that the elevation in the mean costs for third operations was related to very high costs in 4 patients. Sex was found to influence the cost of both primary and third operations (increased cost for women). CONCLUSIONS: Unfavorable outcomes after third coronary artery bypass operations have been associated with preoperatively definable variables, particularly age of 70 years or more. The in-hospital mortality in patients younger than 70 was low, and long-term survival in this group has been favorable. The increased hospital costs associated with third operations are related to high costs in only a few patients and have been unpredictable.

Age Factors↗
PubMed1997

A profile of candidates for repeat myocardial revascularization: implications for selection of treatment.

OBJECTIVES: It is not known whether the results of randomized trials comparing coronary artery bypass grafting to percutaneous transluminal coronary angioplasty for initial revascularization apply to repeat revascularization in patients with prior bypass grafts. We studied the differences between the patients with prior bypass grafts referred for surgery or angioplasty to identify the clinical and angiographic characteristics that correlated best with either choice and to find clues that might aid in selecting one treatment over the other. METHODS: Between 1992 and 1994, 870 patients underwent first isolated reoperation and 793 patients underwent first balloon angioplasty after a previous operation. A jeopardy score (0 to 8 points) was derived for each patient on the basis of the relative size of the ischemic territory. Clinical and angiographic data were analyzed for association with the revascularization strategy. RESULTS: The following characteristics were more prevalent in the reoperation group: male sex, diabetes, hypertension, valvular disease, normocholesterolemia, and severe left ventricular systolic dysfunction; fewer functioning venous and arterial grafts; and a higher jeopardy score (p < 0.01 for all) than in the angioplasty group. A higher jeopardy score, diabetes, and a lower number of functioning arterial or venous grafts were strong, independent predictors of referral for reoperation (p < 0.01 for all). In hospital death and Q-wave infarction (p < 0.01 for both) were more frequent in the reoperation group. CONCLUSIONS: Reoperation was the revascularization procedure of choice when larger regions of myocardium were in jeopardy. Angioplasty was more frequently chosen in the presence of a patent arterial graft to the left anterior descending coronary artery or multiple functioning bypass grafts. Reoperation was associated with a higher risk of in-hospital complications than angioplasty.

Aged↗
PubMed1997

Technical and economic feasibility of reusing disposable perfusion cannulas.

OBJECTIVE(S): The reuse of disposable devices is a potential source of significant cost savings to hospitals. Venous and arterial perfusion cannulas under new and reused conditions were selected to identify the clinical, safety, technical, logistic, and economic issues that must be addressed to realize these savings. METHODS: Single- and dual-stage venous and arterial cannulas from two manufacturers were tested when new, after initial clinical use, and after a single clinical use plus up to nine simulated reuses. Reuse was simulated by end-to-end bending, coupling and uncoupling of the connectors, and by two 1-hour soaks in plasma at 4 degrees and 40 degrees C, respectively. Cannulas were decontaminated and then processed by a peracetic acid-based liquid chemical sterilization system after each use/reuse. Sterilization was validated by eliminating Bacillus subtilis spores from the cannulas on each of five consecutive cycles. Cannulas were tested for physical changes, functional integrity, biocompatibility, and in vivo performance in sheep. A cost analysis was also performed. RESULTS: Sterilization was successfully achieved. Mechanical changes were less than 20% on all variables studied and were undetectable by experienced cardiac surgeons in selective evaluation. No clinically important differences were found between new and reused cannulas, even after nine simulated reuses. Reusing cannulas four times would reduce the cost per procedure from $53 to $19 (64%). CONCLUSIONS: Preliminary data suggest that the perfusion cannulas tested can be safely and efficaciously used five times. Limited reuse of these disposable cannulas is technically feasible and cost-effective. Cannula reuse would result in a small incremental savings; however, with more expensive devices and higher-volume sterilization procedures, the savings could be considerably greater. This program provides a model for evaluation of other single-use medical devices for reuse.

Animals↗
PubMed1997

Reoperation for failure of mitral valve repair.

BACKGROUND AND OBJECTIVE: Mitral valve repair is the procedure of choice to correct mitral regurgitation of all types. Up to 10% of patients who undergo mitral valvuloplasty require late reoperation for recurrent mitral valve dysfunction. To determine the causes of failed mitral valve repair, we examined the surgical pathology of patients who underwent reoperation for failed mitral valve repair. PATIENTS AND RESULTS: From 1986 to 1994, 81 patients had 86 reoperations for recurrent mitral regurgitation after mitral valve repair. Mean age was 59.2 +/- 1.4 years; 55 were men. Primary valve disease was degenerative in 48 patients (59%), rheumatic in 16 (20%), ischemic in 13 (16%), endocarditic in 3 (4%), and congenital in 1 (1%). Mean time interval between initial mitral valve repair and reoperation was 15.6 +/- 2.5 months. Causes of repair failure were procedure-related (50 cases, 58%), valve-related (33 cases, 38%), or unknown (3 cases, 3%). Procedure-related valve failure was caused by suture dehiscence (21 cases), rupture of previously shortened chordae (19 cases), or incomplete initial correction (10 cases). Valve-related repair failure was caused by progressive primary valve disease (27 cases), endocarditis (5 cases), or extensive leaflet retraction (1 case). Repair failure was procedure-related in 70% of patients with degenerative valvular disease versus only 13% of patients with rheumatic valvular disease (p = 0.0001). At reoperation, mitral valve replacement was performed in 64 patients (79%) and repeat mitral valve repair in 17 (21%). CONCLUSION: We conclude that (1) most mitral valve repair failures are procedure-related in degenerative disease and valve-related in rheumatic disease; (2) rupture of previously shortened chordae is a common cause of late failure in patients with degenerative mitral valve disease; and (3) repeat mitral valve repair results in successful treatment for a minority of patients.

Adolescent↗
PubMed1997

Robotic surgical instruments for dexterity enhancement in thoracoscopic coronary artery bypass graft.

OBJECTIVES: Endoscopically sutured vascular anastomoses are complex, time consuming, and require great dexterity. We decided to evaluate performance enhancement using a robotic device to create sutured coronary artery bypass anastomoses with endoscopic techniques in a plastic model. METHODS: Seven coronary artery bypass anastomoses were endoscopically created in a plastic model using a robotic enhancement technology (Computer Motion, Goleta, CA). Anastomoses were created with a single running suture (7-0 monofilament). Our endpoints were operative time, intraoperative incidents, stability and dexterity of the robotic system, surgeon's fatigue, and anastomotic patency. RESULTS: Operative time was 46+/-12 min (mean+/-SD). There were no intraoperative incidents. Patency was confirmed in all anastomoses. The system's stability and dexterity were high. Surgeon's fatigue was mild. CONCLUSION: The use of robotic enhancement technology leads to an efficient performance of sutured coronary artery bypass anastomoses in a plastic model. The robotic device enhances dexterity, precision, and reduces surgeon's fatigue while preserving the quality of hand suturing.

Clinical Competence↗
PubMed1996

Repair of anterior leaflet prolapse: chordal transfer is superior to chordal shortening.

UNLABELLED: Several techniques are currently used to repair anterior leaflets with elongated or ruptured chordae. To evaluate the efficacy of these techniques, we analyzed the case histories of 108 patients operated on from 1989 through 1992 with degenerative mitral valve disease and prolapse of the anterior leaflet. The mean age was 59 +/- 15 years (range 18 to 87 years) and 74 (69%) were male. METHODS: Chordal shortening was performed in 31 (29%) and chordal transfer in 77 (71%) of the repairs. Of the transfers, 58 (75%) were from the posterior to the anterior leaflet and 16 (21%) were from the secondary to the primary position of the anterior leaflet. Three patients had both types of transfers. Seventy-one (66%) patients had isolated repairs and the remainder had associated procedures. The degree of preoperative mitral regurgitation was 3+ or greater for 107 (99%) of the patients, mean 3.4 for shortening and 3.7 for transfer. RESULTS: Four (4.0%) hospital deaths occurred, none after isolated repair. Follow-up of hospital survivors was 100% complete at a mean of 4.0 years. A total of 421 patient-years of follow-up were available for analysis. There were seven late deaths, for a 5-year actuarial survival of 93%. Eleven patients underwent reoperation for recurrent mitral regurgitation. Five-year actuarial freedom from reoperation was 90%-96% after chordal transfer and 74% after chordal shortening, p = 0.003. Independent predictors for reoperation include chordal shortening and preoperative New York Heart Association functional class III or IV. The mechanism of valve failure in six of seven patients undergoing reoperation after chordal shortening was rupture of the previously shortened chordae. CONCLUSIONS: We conclude that chordal transfer is superior to chordal shortening, providing a more predictable correction of mitral regurgitation and a lower incidence of reoperation. Reoperations after chordal shortening are a result of rupture of the previously shortened chordae.

Actuarial Analysis↗
PubMed1996

Surgical treatment of prosthetic valve endocarditis.

From 1975 through 1992, we reoperated on 146 patients for the treatment of prosthetic valve endocarditis. Prosthetic valve endocarditis was considered to be early (< 1 year after operation) in 46 cases and active in 103 cases. The extent of the infection was prosthesis only in 66 patients, anulus in 46, and cardiac invasion in 34. Surgical techniques evolved in the direction of increasingly radical débridement of infected tissue and reconstruction with biologic materials. All patients were treated with prolonged postoperative antibiotic therapy. There were 19 (13%) in-hospital deaths. Univariate analyses demonstrated trends toward increasing risk for patients with active endocarditis and extension of infection beyond the prosthesis; however, the only variables with a significant (p < 0.05) association with increased in-hospital mortality confirmed with multivariate testing were impaired left ventricular function, preoperative heart block, coronary artery disease, and culture of organisms from the surgical specimen. During the study period, mortality decreased from 20% (1975 to 1984) to 10% (1984 to 1992). For hospital survivors the mean length of stay was 25 days. Follow-up (mean interval 62 months) documented a late survival of 82% at 5 postoperative years and 60% at 10 years. Older age was the only factor associated (p = 0.006) with late death. Nineteen patients needed at least one further operation; reoperation-free survival was 75% at 5 and 50% at 10 postoperative years. Fever in the immediate preoperative period was the only factor associated with decreased late reoperation-free survival (p = 0.032). Prosthetic valve endocarditis remains a serious complication of valve replacement, but the in-hospital mortality of reoperations for prosthetic valve endocarditis has declined. With extensive débridement of infected tissue and postoperative antibiotic therapy, the extent and activity of prosthetic valve endocarditis does not appear to have a major impact on late outcome, and the majority of patients with this complication survive for 10 years after the operation.

Adult↗
PubMed1995

Clinical and operative characteristics of patients randomized to coronary artery bypass surgery in the Bypass Angioplasty Revascularization Investigation (BARI).

The surgical cohort of the Bypass Angioplasty Revascularization Investigation (BARI) is the largest group of patients with multivessel coronary artery disease randomly assigned to surgical treatment. This report presents baseline and operative characteristics of the cohort and describes some aspects of the variability in surgical practice among the 14 primary clinical centers and 4 co-investigational sites participating in BARI. Preoperative clinical and angiographic data and intraoperative variables were reviewed in 892 patients who were randomly assigned to coronary artery bypass grafting (CABG) and underwent operation. Associations between patient/lesion variables and operative characteristics are described. Of patients assigned to CABG, 87% underwent an operation within 2 weeks of randomization, as recommended in the protocol. Mean age of the 892 patients was 61 years, and mean age of the 235 women was greater than that of men (64 years vs 60 years); 64% of the surgical patients were classified as having unstable angina during the 6 weeks prior to randomization. Coronary angiography demonstrated 3-vessel disease (50% diameter narrowing by caliper measurement) in 41% of patients, and disease of the left anterior descending coronary artery was present in 87% of patients. A mean of 3.1 coronary arteries per patient were bypassed, and 82% of patients received 1 (70%) or 2 (12%) internal thoracic artery grafts. Prevalence of internal thoracic grafts was lower in elderly patients (74% of patients > or = 70 years), in women (72% vs 85% in men; p < 0.01), and in black participants (65%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

Have PTCA failures requiring emergent bypass operation changed?

From 1980 through 1990, 9,145 patients had balloon angioplasty with failure of the procedure requiring emergent surgical revascularization within 24 hours occurring in 253 patients (2.8%). Patients were divided into two cohorts based on the date of the percutaneous transluminal coronary angioplasty (PTCA): 1980 to 1985 (n = 109) and 1986 to 1990 (n = 144). The incidence of PTCA failure was 3.8% during 1980 to 1985 (109/2,903) and decreased to 2.3% (144/6,242) for 1986 to 1990. Comparison of pre-PTCA patient characteristics between the two periods showed that only a history of a previous PTCA and class III or class IV symptoms were more common in the recent years (p < or = 0.05). In-hospital mortality after emergency operation was 4.6% (5/109) during 1980 to 1985 and 7.6% (11/144) from 1985 to 1990 (p = not significant). This trend toward increased mortality appeared to be related to an increased number of patients who underwent operation in a state of severe hemodynamic compromise in the more recent period. The in-hospital mortality rate for patients in shock or undergoing cardiopulmonary resuscitation was 28.3% (13/46) compared with 1.4% (3/207) for patients with less severe hemodynamic derangement (p < 0.001). Use of the intraaortic balloon pump preoperatively increased from 12.8% to 32.6% (p < 0.01). Late survival was 92% at 2 and 87% at 5 postoperative years. Although the incidence of PTCA failure necessitating emergent surgical intervention has decreased over time, there has been a trend toward an increased in-hospital mortality rate for those patients that does not appear to be related to more severe pre-PTCA characteristics.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1995

You are in charge of cost.

Shifts in medical reimbursement dictate that physicians become knowledgeable about resource consumption. Price drives cost. The patient is now a cost center. Various models of physician-hospital integration are presented. A completely integrated staff in the hospital has the greatest potential for economic efficiency. The best method of cost accounting will include activity-based costs in a format that is understandable for physician education. Hospital cost management involves human resources, ordering practices, length of stay, purchasing, capital requirements, and benchmark targets. As health reform takes shape, physicians should be fully cognizant of cost, understand healthcare issues, and commit to improving the environment in which they practice medicine. The purpose of these activities is to improve the value of healthcare delivery for all patients.

Accounting↗
PubMed1995

The Carpentier-Edwards pericardial aortic valve. Ten-year results.

To evaluate the function of the Carpentier-Edwards pericardial valve in the aortic position, we analyzed the results of 310 aortic valve replacements performed between 1982 and 1985. Mean age was 64.2 +/- 10.8 years (range 22 to 95 years); 190 patients (61.3%) were male patients. There were 18 hospital deaths (5.8%), and none were valve related. Follow-up of the 292 survivors was 100% complete at a mean of 7.8 +/- 2.9 years; 2290 patient-years of follow-up were available for analysis. There were 133 late deaths (45.5%). Actuarial survivals at 5 and 10 years were 82.5% and 45.9%, respectively. The 10-year actuarial freedom from events was 88.7% +/- 2.1% for thromboembolism, 90.9% +/- 1.8% for hemorrhage, 94.3% +/- 1.6% for endocarditis, and 91.2% +/- 2.6% for structural deterioration. The 153 hospital survivors 65 years of age or older had an extremely low incidence of structural valve deterioration, with only four explants and 95.5% actuarial freedom from explantation at 10 years, and a linearized rate of 0.3 +/- 0.2 per patient-year compared with 88.6% and 0.7 +/- 0.2 for patients younger than 65 years of age. Twelve valves were explanted for structural deterioration. Of these, 11 (93%) had leaflet calcification causing stenosis and one had a wear-related leaflet tear. The Carpentier-Edwards pericardial valve has a low incidence of valve-related complications. The freedom from structural valve deterioration is low at 10 years, particularly in patients 65 years of age and older.

Actuarial Analysis↗
PubMed1995

Thoracic Surgery Workforce Report. The fourth report of the Thoracic Surgery Workforce Committee of The American Association for Thoracic Surgery and The Society of Thoracic Surgeons.

To determine demographics, practice patterns, and work volume of North American thoracic surgeons, we sent a detailed survey to all members of The American Association for Thoracic Surgery and The Society of Thoracic Surgeons between January and May 1993 to determine data for 1992; 3049 of 3487 (87%) thoracic surgeons responded and 2677 (88%) were in active practice. Ninety-seven percent were male and 3% female, with a mean age of 52 years. Sixty-five percent considered fee-for-service as their primary compensation mode. Only 24% do isolated subspecialty work: 2% pediatric cardiac surgery. 10% general thoracic surgery, and 12% adult cardiac surgery. Seventy-six percent of respondents do both cardiac and thoracic operations. Workload data for adult cardiac, pediatric cardiac, general thoracic, peripheral vascular, and pacemaker operations were requested. Volume data were cross-correlated with age, 10 geographic regions including Canada, type of practice, and type of compensation and were cross-checked by hospital discharge data for 1992. These data were compared with data from similar surveys performed in 1976, 1980, and 1985, under the auspices of the same two societies; these latter surveys used diplomates of the American Board of Thoracic Surgery as their database. Workloads have increased over previous surveys. Most surgeons do a wide variety of thoracic operations, and exclusive designations are in the minority.

Aged↗
PubMed1995

The use of APACHE III to evaluate ICU length of stay, resource use, and mortality after coronary artery by-pass surgery.

OBJECTIVE: To identify patient characteristics that are associated with increased ICU length of stay, resource use, and hospital mortality after coronary artery bypass surgery. DESIGN: Prospective, multicenter study. SETTING: Six tertiary care hospitals. PARTICIPANTS: A consecutive sample of 2,435 unselected ICU admissions following coronary artery by-pass surgery. MATERIALS AND METHODS: Demographic, operative characteristics and APACHE III score were collected during the first postoperative day; and APACHE III scores and therapeutic interventions during the first three postoperative days. Hospital survival and ICU length of stay were also recorded. Multivariate equations were derived and cross-validated to predict hospital mortality, ICU length of stay, and ICU resource use. RESULTS: Unadjusted hospital mortality rate was 3.9% (range 1.0% to 6.0%), mean ICU length of stay was 3.7 days (range 3.2 to 4.7 days), and first 3-day ICU resource use (TISS points) was 99 (range 68 to 116). The range of actual to predicted ICU length of stay varied from 0.86 to 1.26; and resource use from 0.71 to 1.16. CONCLUSIONS: A limited number of operative characteristics, the post-operative acute physiology score (APS) of APACHE III and patient demographic data can predict hospital death rate, ICU length of stay, and resource use immediately following coronary by-pass surgery. These estimates may compliment assessments based on pre-operative risk factors in order to more precisely evaluate and improve the efficacy and efficiency of cardiovascular surgery.

APACHE↗
PubMed1994

Is the internal thoracic artery the conduit of choice to replace a stenotic vein graft?

Reoperative coronary artery bypass grafting secondary to saphenous vein graft (SVG) stenosis is a mushrooming problem. The internal thoracic artery graft (ITA) provides superior long-term patency, but its flow is limited and may be inadequate to meet large myocardial demands. To evaluate the efficacy of the ITA as a replacement conduit for a stenotic SVG, 387 consecutive patients undergoing reoperative bypass grafting from 1985 to 1990 with a stenotic SVG to a totally obstructed left anterior descending coronary artery (LAD) were analyzed. The patients were divided into four groups according to the management of the previously placed SVG. Group I (n = 155) underwent graft replacement with a new SVG. Group II (n = 90) received an ITA with the old SVG left intact. In group III (n = 37), an ITA was placed to the LAD with an SVG to the diagonal (old graft interrupted). Group IV (n = 104) had an ITA only to the LAD (old graft interrupted). There were 14 deaths (3.6%). Mortality rate was 7.9% for group IV and 2.1% for groups I through III (p = 0.01). Multivariate analyses identified advancing age (p = 0.001), ITA only (p = 0.001), and female sex (p = 0.04) as independent predictors of operative mortality. Evidence of hypoperfusion in the distribution of the LAD was present in 19 patients, all of whom were in group IV (18.9%). Predictors of hypoperfusion were moderate/severe left ventricular function (p = 0.02) and ITA to the LAD with interruption of the old graft (p = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Cause of Death↗
PubMed1994

Systolic anterior motion of mitral valve after the posterior leaflet sliding advancement procedure.

The posterior leaflet sliding advancement procedure was developed to prevent the occurrence of systolic anterior motion of mitral valve and consequently outflow obstruction after mitral annuloplasty. We present a patient with extremely redundant posterior mitral leaflet in whom outflow obstruction developed despite employment of this procedure. This case underscores the utility of preoperative and intraoperative echocardiography in surgical decision making. Systolic anterior motion can develop in some patients despite this new surgical technique.

Humans↗
PubMed1994

Coronary reoperation: results of adding an internal mammary artery graft to a stenotic vein graft.

Although it is desirable at coronary reoperation to replace a stenotic vein graft to the left anterior descending coronary artery (LAD) with an internal mammary artery (IMA) graft, previous reports have shown that if the stenotic vein graft is removed, that strategy can be complicated by severe hemodynamic deterioration and increased perioperative mortality. We report the results for 90 patients in whom an IMA was used to graft a completely obstructed LAD with the stenotic vein graft left intact. For 10 patients, reoperation involved only an IMA-LAD graft, and in 80 patients, a second IMA, veins, or both were used to graft other vessels. There were no hospital deaths. One patient had a perioperative myocardial infarction. Follow-up at a mean postoperative interval of 58 months documented 11 late deaths (eight cardiac related) and actuarial 5-year survival of 88%. Twenty-two patients underwent coronary angiography at a mean postoperative interval of 48 months. The IMA-LAD graft was found to be perfectly patent in 20 and obstructed in 2. The strategy of adding an IMA graft to the LAD and leaving a stenotic vein graft intact has been associated with a low risk of perioperative myocardial infarction, the late clinical results are favorable, and repeat angiography indicates that serious competitive flow from the stenotic vein graft is uncommon.

Adult↗