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G L Grunkemeier

Publications and source records attributed to G L Grunkemeier.

At least 37 records · Page 2Linked to original sources
PubMed1999

Continuous intravenous insulin infusion reduces the incidence of deep sternal wound infection in diabetic patients after cardiac surgical procedures.

BACKGROUND: Diabetes mellitus is a risk factor for deep sternal wound infection after open heart surgical procedures. We previously showed that elevated postoperative blood glucose levels are a predictor of deep sternal wound infection in diabetic patients. Therefore, we hypothesized that aggressive intravenous pharmacologic control of postoperative blood glucose levels would reduce the incidence of deep sternal wound infection. METHODS: In a prospective study of 2,467 consecutive diabetic patients who underwent open heart surgical procedures between 1987 and 1997, perioperative blood glucose levels were recorded every 1 to 2 hours. Patients were classified into two sequential groups: the control group included 968 patients treated with sliding-scale-guided intermittent subcutaneous insulin injections (SQI); the study group included 1,499 patients treated with a continuous intravenous insulin infusion in an attempt to maintain a blood glucose level of less than 200 mg/dL. There were no differences between these groups with respect to age, sex, procedure, bypass time, antibiotic prophylaxis, or skin preparation methods. RESULTS: Compared with subcutaneous insulin injections, continuous intravenous insulin infusion induced a significant reduction in perioperative blood glucose levels, which led to a significant reduction in the incidence of deep sternal wound infection in the continuous intravenous insulin infusion group (0.8% [12 of 1,499]) versus the intermittent subcutaneous insulin injection group (2.0% [19 of 968], p = 0.01 by the chi2 test). Multivariate logistic regression revealed that continuous intravenous insulin infusion induced a significant decrease in the risk of deep sternal wound infection (p = 0.005; relative risk, 0.34), whereas obesity (p < 0.03; relative risk, 1.06) and use of an internal thoracic artery pedicle (p = 0.1; relative risk, 2.0) increased the risk of deep sternal wound infection. CONCLUSIONS: Use of perioperative continuous intravenous insulin infusion in diabetic patients undergoing open heart surgical procedures significantly reduces major infectious morbidity and its associated socioeconomic costs.

Aged↗
PubMed1999

Bileaflet mechanical prostheses performance in mitral position.

OBJECTIVE: The experience with the Carbomedics (CM) and the St. Jude Medical (SJM) bileaflet mechanical prostheses was evaluated to determine thromboembolic and hemorrhagic complications and predictive risk factors. METHODS: From 1989 to 1994, a total of 625 patients had mitral valve replacement (CM, 240; SJM, 385); 32.5% (203), concomitant procedures and 32.8% (205), previous cardiac surgery, primarily valve replacement procedures. RESULTS: The pre-operative variables did not distinguish the populations, except for previous surgery CM 37.9% and SJM 29.6% (P < 0.05). The pre-operative variables (type of prostheses, cardiac rhythm, coronary artery bypass, NYHA III/IV, advancing age, gender, urgency status and previous surgery) were not predictive of overall thromboembolism (TE), major TE, minor TE, prosthesis thrombosis and hemorrhage (P not significant; P = NS). The linearized rate of total TE events for overall MVR was 5.0%/patient-year (CM 4.4; SJM 5.4). The < or = 30 day major crude rate was 0.44%, while the > 30 day late major event rate was 2.0%/patient-year. Of the total TE events 91% of < or = 30 days and 75%, > 30 days had an INR < 2.5 at or immediately prior to the event. The thrombosis rate (included in TE events) was 0.63%/patient-year (ten events, four managed successfully with thrombolysis, five successfully with reoperation, and one fatality identified at autopsy). The freedom, at 5 years, from major/fatal TE, thrombosis and hemorrhage from anticoagulation was 88.2%, and 89.5% exclusive of early events. CONCLUSIONS: This non-randomized prospective observational evaluation of the CarboMedics and St. Jude Medical prostheses has not revealed any differentiation in performance of the prostheses. The study serves as a single institution experience with the potential for future comparative evaluation.

Adult↗
PubMed1999

Bileaflet mechanical prostheses for aortic valve replacement in patients younger than 65 years and 65 years of age or older: major thromboembolic and hemorrhagic complications.

OBJECTIVE: To determine major thromboembolic and hemorrhagic complications and predictive risk factors associated with aortic valve replacement (AVR), using bileaflet mechanical prostheses (CarboMedics and St. Jude Medical). DESIGN: A case series. SETTING: Cardiac surgical services at the teaching institutions of the University of British Columbia. PATIENTS AND METHODS: Patients 2 age groups who had undergone AVR between 1989 and 1994 were studied. Group 1 comprised 384 patients younger than 65 years. Group 2 comprised 215 patients 65 years of age and older. RESULTS: The linearized rates of major thromboembolism (TE) occurring after AVR were 1.54%/patient-year for group 1 and 3.32%/patient-year for group 2; the rates for major TE occurring more than 30 days after AVR were 1.13%/patient-year for group 1 and 1.55%/patient-year for group 2. The crude rates for major TE occurring within 30 days of AVR were 1.04% for group 1 and 3.72% for group 2. The death rate from major TE in group 1 was 0.31%/patient-year and in group 2 was 0.88%/patient-year. Of the major TE events occurring within 30 days, 100% of patients in both age groups were inadequately anticoagulated at the time of the event, and for events occurring more than 30 days after AVR, 45% in group 1 and 57% in group 2 were inadequately anticoagulated (INR less than 2.0). The overall linearized rates of major hemorrhage were 1.54%/patient-year for group 1 and 2.21%/patient-year for group 2. There were no cases of prosthesis thrombosis in either group. The mean (and standard error) overall freedom from major TE for group 1 patients at 5 years was 95.6% (1.4%) and with exclusion of early events was 96.7% (1.3%); for group 2 patients the rates were 90.0% (3.2%) and 93.7% (3.0%), respectively. The mean (and SE) overall freedom from major and fatal TE and hemorrhage for group 1 patients was 90.1% (2.3%) and with exclusion of early events was 91.2% (2.3%); for group 2 patients the rates were 87.9% (3.1%) and 92.5% (2.9%), respectively. The 5-year rate for freedom from valve-related death for group 1 patients was 96.3% (2.1%) and for group 2 patients was 97.2% (1.2%). CONCLUSION: The thromboembolic and hemorrhagic complications after AVR with bileaflet mechanical prostheses occur more frequently and result in more deaths in patients 65 years of age and older than in patients years younger than 65 years.

Adult↗
PubMed1999

Artificial Valve Endocarditis Reduction Trial (AVERT): protocol of a multicenter randomized trial.

BACKGROUND AND AIM OF THE STUDY: This article presents the protocol of the Artificial Valve Endocarditis Reduction Trial (AVERT), a multicenter, international randomized trial to assess the efficacy of the SilzoneTM coating of St. Jude Medical Masters Series mechanical heart valves in the prevention of prosthetic heart valve endocarditis (PVE). A total of 4,400 eligible patients will be randomized within three years of study commencement at 17 participating clinical centers in North America and Europe, with study completion within four years. ELIGIBILITY CRITERIA: Eligible patients are candidates for St. Jude mechanical valves with either the Silzone or conventional cuff, in the mitral and/or aortic position, who give informed written consent to participate. Major exclusion criteria are the presence of prosthetic valves that do not require replacement, and the need for tricuspid valve replacement. Bypass surgery and valve repair are allowed during the implant operation. Patients will be randomized using an envelope-based intraoperative randomization scheme, stratified by clinical center and by the presence of endocarditis at the time of surgery. FOLLOW UP: Patients will be contacted at discharge, three months, and each anniversary of the implant procedure. A brief follow up survey, administered via clinic interview, telephone or mail, will elicit events associated with possible endocarditis (unexplained fever, worsening angina, hospitalization) that will initiate contact with the patient's following physician. OUTCOME ANALYSIS: The primary PVE endpoint will be based upon a published algorithm, with two infectious disease specialists making the final determination of cases classified as possible endocarditis. Study data will be periodically reviewed by a Data Safety Monitoring Board. The primary analysis will be an intention-to-treat comparison of freedom from PVE curves between the Silzone and conventional cuff treatment groups. CONCLUSIONS: AVERT will provide much-needed information on the effectiveness of Silzone in preventing PVE, as well as practice patterns and outcomes of valve replacement.

Clinical Protocols↗
PubMed1999

Heart valve replacement: a statistical review of 35 years' results.

BACKGROUND AND AIMS OF THE STUDY: Having performed our first heart valve replacement in 1960, we began a prospective lifetime follow up service for all patients, contacting them at least annually to determine survivorship and heart valve complications. METHODS: We reviewed isolated aortic (AVR) and mitral (MVR) valve replacements from 1960 to 1993, with follow up to 1998. In total, 2,942 AVR and 1,579 MVR were performed, with 21,742 and 12,142 patient-years of follow up, respectively. Analysis of the results affords an opportunity to demonstrate the usefulness and necessity of certain statistical methods, including multivariable event-free analyses and cumulative incidence functions. RESULTS: The survival rate was 8% at 30 years for both valve positions. However, an overall survival curve is an artificial composite of patients of increasingly higher risk being served during increasingly safer years of calendar time. One result is that, for AVR, age is not a significant univariate risk factor for operative mortality, but is highly significant after accounting for date of surgery using logistic regression. Long-term mortality is higher for tissue valves than for mechanical valves; but mean age is greater (74 versus 57 years), and after accounting for age using Cox regression, mortality is similar for both valve types. Kaplan-Meier analysis estimates thromboembolism occurrences of 85% for AVR and 95% for MVR at 35 and 34 years, respectively, but the cumulative incidence estimates are only 32% and 41%, respectively. CONCLUSIONS: Prospective follow up for over 35 years has provided an opportunity to illustrate important statistical issues: Multivariate analyses are essential to avoid being misled by excluding important risk factors or including artifactual ones, and the cumulative incidence estimates the percentage of patients who will actually experience a complication.

Adult↗
PubMed1998

Mitral valve replacement: randomized trial of St. Jude and Medtronic Hall prostheses.

BACKGROUND: This study was designed to better define the merits of the bileaflet and tilting-disc valves. METHODS: We prospectively randomized 156 patients (mean age, 59 years) to receive either the St. Jude (n = 80) or the Medtronic Hall (n = 76) mitral valve prosthesis between September 1986 and December 1997. The two groups were not significantly different with respect to preoperative New York Heart Association class, left ventricular ejection fraction, incidence of mitral stenosis or insufficiency, extent of coronary artery disease, completeness of revascularization, or cross-clamp or bypass time. RESULTS: The operative mortality (11.2% versus 13.1%, St. Jude versus Medtronic Hall, respectively) and late mortality (27% versus 22%, St. Jude versus Medtronic Hall, respectively) were not significantly different. Follow-up was complete in all hospital survivors with a mean of 60.7 months (range, 1 to 133 months). The analysis of 10-year actuarial survival and freedom from valve-related events demonstrated no significant differences between the cohorts. Freedom from reoperation was higher in the St. Jude group (p < 0.01). Comparisons of patient functional status and echocardiographic hemodynamic parameters obtained at the time of follow-up demonstrated no significant differences between the two prostheses. CONCLUSIONS: This study suggests that there is no difference between the St. Jude and Medtronic Hall prostheses with respect to late clinical performance or hemodynamic results and therefore does not support the preferential selection of either prosthesis.

Aged↗
PubMed1998

Multiple mechanical valve replacement surgery comparison of St. Jude Medical and CarboMedics prostheses.

OBJECTIVE: The experience with the St. Jude Medical (SJM) and CarboMedics (CM) bileaflet mechanical prostheses was evaluated to determine thromboembolic and hemorrhagic complications and predictive risk factors. METHODS: From 1989 to 1994, a total of 246 patients had multiple valve replacement (SJM, 140; CM, 106); concomitant procedures 20.3% (50) [coronary artery bypass 10.6% (26)] and 53.7% (132) previous cardiac surgery, primarily valve replacement procedures. The pre-operative variables [coronary artery disease, previous cardiovascular surgery, concomitant procedures, valve lesion (except mitral stenosis), status, atrial fibrillation, and NYHA III/IV] did not distinguish the prosthesis-type (pNS). RESULTS: The prosthesis-type and the pre-operative variables, including atrial fibrillation, were not predictive of overall thromboembolism (TE). The linearized rate of total TE events for overall multiple replacements (MR) was 5.4%/patient-year (minor, 2.52; major 2.85); the total TE for CM and SJM was 5.4%/patient-year, respectively. The < or = 30 day major TE crude rate was 0.82%, while the > 30 day major event rate was 2.7%/patient-year. Of the total (major and minor) TE events 100% (3) of < or = 30 days and 72% (29), > 30 days had an INR < 2.5 at or immediately prior to the event. The thrombosis rate (included in total TE events) was 0.67%/patient-year (4 events, 100% INR < 2.5). Of the various TE event categories the prosthesis-types (CM and SJM) were not differentiated (pNS). The freedom, at 5 years, from major/fatal TE, thrombosis and hemorrhage from anticoagulation was 89.3 +/- 3.8% for CM and 87.9 +/- 3.7% for SJM and, 91.3 +/- 3.5% and 89.3 +/- 3.7%, respectively, (pNS) exclusive of early events. CONCLUSIONS: The performance of the CarboMedics and St. Jude Medical prostheses in multiple valve replacement surgery in this non-randomized prospective study revealed no significant differences in performance with regard to thromboembolic and hemorrhagic complications.

Adult↗
PubMed1998

Clinical evaluation and analysis of heart valve substitutes.

We discuss the clinical assessment of heart valve substitutes, primarily with regard to pre-market evaluation. We concentrate on the current FDA heart valve guidance document. This guidance is self-acknowledged to be an evolving document, scheduled to be revised between three and five years after its initial release on December 1993. We outline the history and some of the strengths of the present system, and discuss areas for possible improvement. We selected one important statistical issue to address thoroughly how to compute the confidence limit of a linearized rate.

Bioprosthesis↗
PubMed1998

The Ultracor tilting disc heart valve prosthesis: a seven-year study.

BACKGROUND AND AIM OF THE STUDY: The Ultracor heart valve is a recent entry in the evolution of the tilting disc valve. This report summarizes the experience with the Ultracor valve from three European centers. METHODS: Between 1990 and 1996, 446 patients received 499 Ultracor heart valve prostheses in 450 procedures, including 225 (50.0%) aortic, 172 (38.2%) mitral and 49 (10.9%) double valve replacements. An additional four (1.0%) patients had mitral valve replacement (MVR) added to a previous aortic valve replacement (AVR) and were considered double valve replacement (DVR) patients. The total follow up was 751 patient-years (pt-yr) for AVR (mean 3.4), 440 pt-yr for MVR (mean 2.6) and 125 pt-yr for DVR (mean 2.4). Nine patients (one AVR, eight MVR) were lost to follow up, which was 98% complete. RESULTS: The actuarial survival rate, including operative mortality rate, at five years was 90% for AVR, 77% for MVR and 82% for DVR. The linearized complication rates (%/year) for AVR, MVR and DVR were: 2.1, 4.0 and 4.0 for late mortality; 0.1, 3.0 and 0.8 for thromboembolism; 0, 0.2 and 0 for thrombosis; 2.0, 1.6 and 1.6 for anticoagulant-related hemorrhage (ACH); 0.3, 0.5 and 1.6 for prosthetic valve endocarditis (PVE); and 0.5, 0.9 and 3.2 for reoperation, respectively. The actuarial rates of freedom from complications at five years were: thromboembolism, 99% for AVR and 88% for MVR; thrombosis, 100% for AVR and 99% for MVR; ACH, 91% for AVR and 94% for MVR; PVE, 99% for AVR and 97% for MVR; reoperation, 98% for AVR and 98% for MVR. No structural failure was observed. CONCLUSIONS: Seven years' experience showed the Ultracor heart valve prosthesis to be comparable with other currently used mechanical heart valves. Continued evaluation of this prosthesis is warranted in order to obtain a more extended clinical follow up.

Adult↗
PubMed1997

Time-related analysis of nonfatal heart valve complications: cumulative incidence (actual) versus Kaplan-Meier (actuarial).

BACKGROUND: The cumulative incidence of a postoperative event is the percentage of patients who experience the event by postoperative time T. Its complete determination requires all patients to be followed until T. In ongoing series, the Kaplan-Meier method is employed because not all patients have been observed until T. When applied to nonfatal events, however, the Kaplan-Meier estimates probabilities as if the patients who die before they sustain an event continue to be at risk thereafter. It thus estimates risk in the unrealistic situation where death does not occur. METHODS AND RESULTS: Cumulative incidence can be estimated directly, to provide the probability of actually experiencing an event before death, that is, when death properly eliminates patients from further risk of the event. We compare cumulative incidence and Kaplan-Meier estimates in two series of mitral valve replacement patients: thromboembolism in a completed series of ball valves implanted in relatively young patients and valve explant in an ongoing series of porcine valves in older patients. Kaplan-Meier estimated a higher event percentage than the cumulative incidence, and the difference was greater in the older patients, who had a higher death rate. CONCLUSIONS: Cumulative incidence, unlike Kaplan-Meier, provides estimates of the percentage of patients who will actually sustain an event. Cumulative incidence is more meaningful for individual patient counseling and more useful for estimating resource utilization in a managed population.

Aged↗
PubMed1997

Glucose control lowers the risk of wound infection in diabetics after open heart operations.

BACKGROUND: Elevated blood glucose levels in the postoperative period are associated with an increased risk of deep wound infection in diabetic individuals undergoing open heart operations at Providence St. Vincent Hospital. METHODS: Of 8,910 patients who underwent cardiac operations between 1987 and 1993, 1,585 (18%) were diabetic. The rate of deep sternal wound infections in diabetic patients was 1.7%, versus 0.4% for nondiabetics. Nine hundred ninety patients had their operation before implementation of the protocol and 595 after implementation. Charts of all diabetic patients were reviewed. Mean blood glucose levels were calculated from documented results of finger-stick glucometer testing. RESULTS: Thirty-three diabetic patients suffered 35 deep wound infections: 27 sternal (1.7%) and eight at the donor site (0.5%). Infected diabetic patients had a higher mean blood glucose level through the first 2 postoperative days than noninfected patients (208 +/- 7.1 versus 190 +/- 0.8 mg/dL; p < 0.003) and had a greater body mass index (31.5 +/- 1.4 versus 28.6 +/- 0.1 kg/m2; p < 0.05). Multivariable logistic regression showed that mean blood glucose level for the first 2 days (p = 0.002), obesity (p < 0.002), and use of the internal mammary artery (p < 0.02) were all independent predictors of deep wound infection. Institution of a protocol of postoperative continuous intravenous insulin to maintain blood glucose level less than 200 mg/dL was begun in September 1991. This protocol resulted in a decrease in blood glucose levels for the first 2 postoperative days and a concomitant decrease in the proportion of patients with deep wound infections, from 2.4% (24/990) to 1.5% (9/595) (p < 0.02). CONCLUSIONS: The incidence of deep wound infection in diabetic patients was reduced after implementation of a protocol to maintain mean blood glucose level less than 200 mg/dL in the immediate postoperative period.

Aged↗
PubMed1997

Risk, diagnosis and management of prosthetic valve endocarditis: a review.

Prosthetic valve endocarditis (PVE) emerged approximately 37 years ago when the first human heart valve replacements were performed. PVE can be classified as 'early' or 'late' with the pathophysiology and etiologic organisms varying between the two subgroups. The incidence of PVE ranges up to 0.5% per patient-year for mechanical mitral valves and up to 1.0% per patient-year for other valves. The clinical presentation is similar to that of native valve endocarditis, with fever being the most prevalent sign. Diagnosis is based on a constellation of clinical signs and symptoms as well as echocardiographic evaluation of the valve and perivalvular tissues. An algorithm is set forth for diagnosis and management of patients with suspected PVE based on our personal experience and the published literature. Indications for surgery, the surgical approach and methods of PVE prophylaxis and prevention are discussed.

Algorithms↗
PubMed1996

Aortic valve replacement in elderly patients: influence of concomitant coronary grafting on late survival.

BACKGROUND: Aortic valve replacement (AVR) has been an accepted therapy for elderly patients (> 70 years) with aortic valve disease. This study was designed to investigate the determinants of survival after the implantation of aortic valve prostheses, with emphasis on the effect of concomitant coronary artery bypass grafting on survival. METHODS: From November 1964 to July 1994,963 elderly patients underwent isolated AVR. Long-term survival was investigated in 877 patients (70 to 94 years) who survived operation, with 92% follow-up completeness (mean +/- standard deviation, 4.5 +/- 3.9 years; maximum, 20.1 years; total, 3,920.2 patient-years), by univariate and multivariate analyses. RESULTS: Actuarial survival was 38.1% +/- 2.8% at 10 years, 17.8% +/- 3.0% at 15 years, and 9.0% +/- 3.1% at 20 years. Eight variables (age, sex, body surface area [less or greater than 1.7 m2], period of operation, type of prosthesis, size of prosthesis, re-replacement, and concomitant coronary artery bypass grafting) were investigated with regard to long-term survival by the Kaplan-Meier method. Age, sex, and body surface area were significant. Multivariate analysis revealed that older age (p = 0.0005) and male sex (p = 0.0001) were independent variables that determined long-term survival. CONCLUSIONS: Elderly patients may have satisfactory long-term results after AVR. Age and sex are independent determinants. Other factors (such as concomitant coronary artery bypass grafting and type of prosthesis) did not independently influence long-term survival. Coronary revascularization in elderly patients with coronary disease undergoing AVR may lead to a long-term survival similar to that in patients without coronary disease undergoing AVR.

Actuarial Analysis↗
PubMed1996

Guidelines for reporting morbidity and mortality after cardiac valvular operations. The American Association for Thoracic Surgery, Ad Hoc Liaison Committee for Standardizing Definitions of Prosthetic Heart Valve Morbidity.

At the request of the Councils of The Society of Thoracic Surgeons (STS) and The American Association for Thoracic Surgery (AATS) the Ad Hoc Liaison Committee for Standardizing Definitions of Prosthetic Heart Valve Morbidity "revisited" the "Guidelines" published in September 1988 [1-3]. The purpose of the review was to update and clarify definitions within the guidelines and to consider recommendations made by others [4, 5]. The variety of cardiac valvular procedures has expanded since 1988; therefore, in this document the term "operated valve" indicates prosthetic and bioprosthetic heart valves of all types: operated or repaired native valves and allograft and autograft valves. The term "operated valve" includes any cardiac valve altered by a surgeon during an operation. Much morbidity and mortality is a direct consequence of the interaction between the patient and operated valve(s), although patient variables (e.g., age, degree of coronary arterial disease, follow-up care) may be more responsible for outcomes than an operated valve. However, no set of guidelines can identify all possible patient factors that may affect morbidity and mortality. General agreement regarding the following definitions of terms and suggestions for reporting data do not preclude more detailed analyses or constructive recommendations and investigators are encouraged to identify relevant patient factors in addition to factors related to operated valves.

Documentation↗
PubMed1996

Long-term outcome, survival analysis, and risk stratification of dynamic cardiomyoplasty.

METHODS: To analyze the long-term outcome of dynamic cardiomyoplasty, we retrospectively studied 127 consecutive patients who underwent this procedure in Paris, France (n = 76), São Paulo, Brazil (n = 37), and Portland, Oregon (n = 14). Preoperative data were collected for patients operated on between January 1985 and June 1994 and examined with respect to effect on long-term survival. Patients had a mean age of 50 +/- 13 years and were predominantly male (82%). In 46% the cause of disease was ischemic. Concomitant operations were performed in 22 patients. RESULTS: Operative mortality was 12% (15/127). Kaplan-Meier survival +/- standard error at 1 through 5 years was 73% +/- 4%, 57% +/- 5%, 49% +/- 6%, 44% +/- 6%, and 40% +/- 7%, respectively. There was a distinct improvement at 6 months in New York Heart Association functional class (3.2 +/- 0.05 vs 1.7 +/- 0.07, p < 0.0001) and a small but significant increase in left ventricular ejection fraction (20% +/- 0.8% vs 23% +/- 1.5%, p = 0.04). Ninety-day mortality was associated with low right ventricular ejection fraction, a blunted hemodynamic response to exercise testing, and requirement for an intraaortic balloon pump at the time of the operation. Using a stepwise Cox regression method of multivariable survival analysis (n = 101), we determined that atrial fibrillation, New York Heart Association class IV, high pulmonary capillary wedge pressure, and balloon pump use were independent variables simultaneously associated with poor overall survival. When metabolic testing variables were added to this model, peak oxygen consumption eliminated both pulmonary capillary wedge pressure and functional class from the model, albeit with fewer (n = 74) patients. CONCLUSION: Dynamic cardiomyoplasty is an evolving therapy for symptomatic congestive heart failure, the results of which may be enhanced by intelligent, risk-sensitive patient selection.

Cardiomyoplasty↗
PubMed1996

Is referral source a risk factor for coronary surgery? Health maintenance organization versus fee-for-service system.

We began performing coronary artery bypass grafting for a large health maintenance organization (HMO) in 1974, as the sole provider of their cardiac surgery. The outcomes of our HMO group of patients were compared with those of our patients treated on a fee-for-service (FFS) basis. The HMO system entails preintervention and multidisciplinary screening conferences and is devoid of self-referral and personal financial incentives. Since 1985, the operative mortality for HMO patients has been consistently lower than for FFS patients. There were 8483 operations during this study period: 3168 (37%) were in the HMO group, with an overall operative mortality of 2.7%, and 5315 (63%) were in the FFS group, with an operative mortality of 4.6% (p=0.00002). This difference was investigated with univariate and multivariable analyses. Sixteen factors were found to univariately affect the risk of operative mortality; for five of these risk correlates there was a significant maldistribution between the HMO and FFS patients. Logistic regression was used to explore the influence of this imbalance in risk factors. The model found seven independent risk factors (left ventricular failure, emergency coronary bypass, redo bypass, nonuse of the internal thoracic artery, unstable angina, age, and diabetes) that significantly affected operative mortality. The FFS group variable closely approached independent risk significance at p=0.059. This multivariable model explained only one third of the observed differences in actual mortality between the HMO and FFS groups. The system-wide angioplasty/coronary bypass ratio, which could not be used in a patient-specific model, was 0.6 in the HMO system and 1.5 in the FFS group. Other factors related to the operating structure of a mature, large HMO may account for the remainder of the difference. The HMO referral system, through a powerful selection process, resulted in fewer emergencies, redo bypass operations, and catheterization complications that, in turn, yielded lower operative mortality than a noncoordinated FFS system of cardiovascular management.

Angioplasty, Balloon, Coronary↗
PubMed1996

Guidelines for reporting morbidity and mortality after cardiac valvular operations.

At the request of the Councils of the Society of Thoracic Surgeons (STS) and the American Association of Thoracic Surgery (AATS) the Ad Hoc Liaison Committee for Standardizing Definitions of Prosthetic Heart Valve Morbidity reviewed the "Guidelines" published in September 1988 [3, 7, 8]. The purpose of the review was to update and clarify definitions within the guidelines and to consider recommendations made by other [2, 11]. The variety of cardiac valvular procedures has expanded since 1988; therefore, in this document the term "operated valve" indicates prosthetic and bioprosthetic heart valves of all types, operated or repaired native valves and allograft and autograft valves. The term "operated valve" includes any cardiac valve altered by a surgeon during an operation. Much morbidity and mortality is a direct consequence of the interaction between the patient and operated valve(s), although patient variables (e.g., age, degree of coronary arterial disease, follow-up care, etc.) may be more responsible for outcomes than an operated valve. However, no set of guidelines can identify all possible patient factors that may affect morbidity and mortality. General agreement regarding the following definitions of terms and suggestions for reporting data do not preclude more detailed analyses or constructive recommendations and investigators are encouraged to identify relevant patient factors in addition to factors related to operated valves. Purpose The purpose of these guidelines is to facilitate the analysis and reporting of results of operations on diseased cardiac valves. The definitions and recommendations that follow are guidelines, not standards, and are designed to facilitate comparisons between the experiences of different surgeons who treat different cohorts of patients at different times with different techniques and materials.

Data Collection↗