Risk factors for postoperative morbidity

OBJECTIVE: Analysis of outcomes after coronary artery bypass grafting has focused on risk factors for operative mortality. Nonfatal perioperative morbidity is far more costly and more common after operation. To identify the risk factors that lead to postoperative morbidity, we evaluated 938 patients undergoing coronary artery bypass grafting at Albany Medical Center Hospital during 1993. METHODS: Multivariate statistical analysis was performed on preoperative patient variables to identify risk factors for either serious postoperative morbidity or increased hospital length of stay. Variables were considered both individually and in combination. For example, age was considered individually or in combination with other variables, including parameters of blood volume (i.e., age divided by red blood cell volume or Age/RBCVOL). Similar multivariate analysis was performed to identify independent risk factors for hospital mortality. RESULTS: In order of decreasing importance, the following patient variables were significantly associated with increased length of stay by stepwise Cox regression analysis: Age/RBCVOL, history of congestive heart failure, hypertension, femoral-popliteal peripheral vascular disease, chronic obstructive lung disease, and renal dysfunction. The combination variable, Age/RBCVOL, was an important risk factor for both increased length of stay and serious postoperative morbidity. Variables that were significant independent predictors of increased mortality, such as preoperative shock, and redo operation, were not risk factors for either serious morbidity or increased length of stay. CONCLUSIONS: We conclude that risk factors for postoperative morbidity are different from those for postoperative mortality. These results suggest that older patients with preoperative anemia and low blood volume who also have other comorbidities (congestive heart failure, stroke, chronic obstructive pulmonary disease, or hypertension) are at increased risk for postoperative complications. This allows identification of a high-risk cohort of patients who are likely candidates for interventions to lessen postoperative morbidity.     

Elimination of cardiopulmonary bypass: a prime goal in reoperative coronary artery bypass surgery

OBJECTIVE: The purpose of this study was to evaluate morbidity and mortality in reoperative coronary artery bypass surgery using the New York State database. METHODS: Patients undergoing reoperative coronary artery bypass between January-1995 and December 1996 were included. Patients were operated using cardiopulmonary bypass (CPB group, n = 184) or without cardiopulmonary bypass (non-CPB group, n = 105) by surgeon preference. Groups were compared for preoperative risk factors, postoperative mortality and major complications. RESULTS: Crude mortality was lower in the non-CPB group, despite a higher expected mortality, resulting in a risk-adjusted mortality of 1.3% versus 2.7% for the CPB group (NS). Of non-CPB patients, 91.4% were without complications, while only 72.1% of CPB patients (P < 0.0001) were complication-free. Major complications were significantly reduced in non-CPB patients compared to CPB patients: stroke 0% versus 3.8% (P < 0.04), cardiovascular complications 4.8% versus 15.8% (P < 0.005), other major complications 1.9% versus 10.4% (P < 0.007). Postoperative IABP support was needed in 1.9% of the non-CPB group patients and in 14.2% of the CPB group (P < 0.0007). CONCLUSIONS: The main object of reoperative CABG is to relieve symptoms, since the survival benefit of the procedure has not been demonstrated. Performance of reoperative coronary artery bypass surgery without cardiopulmonary bypass significantly reduces morbidity. We conclude that cardiopulmonary bypass should be avoided whenever possible in reoperative coronary bypass surgery.     

Female sex is associated with increased mortality and morbidity early, but not late, after coronary artery bypass grafting

OBJECTIVE: To describe mortality and morbidity during a period of 2 years after coronary artery bypass grafting in relation to gender. DESIGN: Prospective follow-up study. SETTING: Two regional cardiothoracic centres which performed all the coronary artery bypass operations in western Sweden at the time. SUBJECTS: A total of 2129 (1727 (81%) men and 402 (19%) women) consecutive patients undergoing coronary artery bypass surgery between June 1988 and June 1991 without concomitant procedures. RESULTS: Females were older and more frequently had a history of hypertension, diabetes mellitus, congestive heart failure, renal dysfunction and obesity. In a multivariate analysis, taking account of age, history of cardiovascular diseases and renal dysfunction, female sex appeared as a significant independent predictor of mortality during the 30 days after coronary artery bypass grafting (P < 0.05), but not thereafter. Various postoperative complications including neurological deficit, hydro- and pneumo-thorax, perioperative myocardial damage and the need for assist devices and prolonged reperfusion were more common in females than males. CONCLUSION: Females run an increased risk of early death and the development of postoperative complications after coronary artery bypass surgery as compared with males. Late mortality does not appear to be influenced by gender and the long-term benefit of the coronary artery bypass graft operation is similar in men and women.     

Fructosamine in obese normal subjects and type 2 diabetes

Occult coronary artery disease often accompanies symptomatic peripheral vascular disease and has an important effect on survival. Most perioperative and late fatalities after peripheral vascular operations are due to cardiac causes. Noninvasive cardiac testing can identify patients at increased risk for postoperative cardiac complications, although controversy exists regarding the optimal preoperative evaluation. Risk reduction strategies for patients known to be at high risk are also controversial. Some authors advocate coronary revascularization with coronary artery bypass grafting or percutaneous transluminal coronary angioplasty before the vascular procedure. Others believe that the combined morbidity and mortality of 2 operations exceed those of a peripheral vascular operation performed with aggressive monitoring and medical therapy. Continuous electrocardiographic monitoring after an operation has identified silent myocardial ischemia as a powerful predictor of cardiac complications. Ongoing research is likely to provide insights into the pathogenesis of postoperative cardiac complications and may lead to specific therapeutic interventions. Few prospective studies have been done in this area, and the threshold for preoperative and postoperative intervention is unknown. I review the literature and present an algorithm to guide cardiac testing and risk reduction in patients undergoing elective vascular surgical procedures.     

Effect of different methods of internal thoracic artery harvest on pulmonary function

BACKGROUND: In several clinical studies, internal thoracic artery (ITA) grafting for myocardial revascularization has been identified as increasing the risk of postoperative pulmonary complications. This study was designed to determine whether the technique used to harvest the ITA has an effect on postoperative pulmonary function. METHODS: Seventy-nine consecutive patients undergoing coronary artery bypass grafting using the left ITA were compared with patients undergoing coronary artery bypass grafting using saphenous vein grafts only. Two methods of ITA harvesting were used: (1) incision of the endothoracic fascia dissected off the ITA as a skeletonized vessel (group 1, n = 33) and (2) mobilization of the ITA as a wide musculofascial pedicle (group 2, n = 46). Thirty-two patients underwent coronary artery bypass grafting using saphenous vein grafts only (group 3). Pulmonary function tests were performed between postoperative days 20 and 30. RESULTS: The postoperative values of forced vital capacity were reduced in patients in all groups (p < 0.0001). The ratios of postoperative to preoperative forced vital capacity were 84% in group 1, 77% in group 2, and 84% in group 3. The reduction in group 2 was significant compared with group 1 (p < 0.05) and group 3 (p < 0.05). CONCLUSIONS: Postoperative pulmonary dysfunction was significantly greater in patients who underwent wide musculofascial pedicle dissection of the ITA compared with skeletonization of the artery. Thus, of the two techniques, the latter may be the method of choice with regard to lowering the incidence of postoperative pulmonary dysfunction.     

Determinants of early and late results of combined valve operations and coronary artery bypass grafting

BACKGROUND: Factors determining the outcome of operative correction of valvular abnormalities combined with coronary artery bypass grafting are still incompletely defined. METHODS: Determinants of early and late (more than 90 days) deaths and event-free survival were studied for combined valve operations and coronary artery bypass grafting in 741 patients using multivariate analysis. RESULTS: Ninety-day survival probability was 89% (95% confidence interval, 87% to 92%). Preoperative risk factors for early death were age, female sex, renal failure, New York Heart Association class IV or V, and mitral insufficiency. The operative risk factor was the duration of aortic cross-clamping. Five- and 10-year survival probabilities were 74% (95% confidence interval, 71% to 78%) and 43% (95% confidence interval, 36% to 50%), respectively. Preoperative risk factors for late death were age, preoperative renal failure, New York Heart Association class IV or V, vessel disease, and nonsinus rhythm. Five- and 10-year event-free survival probabilities were 57% (95% confidence interval, 53% to 61%) and 23% (95% confidence interval, 17% to 28%), respectively. Preoperative risk factors for non-event-free survival were age, female sex, reduced left ventricular function, mitral regurgitation, and pacemaker rhythm. CONCLUSION: The demographic factors of age and female sex; the comorbid condition of renal failure; the cardiac conditions of advanced New York Heart Association class, left ventricular function, mitral regurgitation, vessel disease, and cardiac rhythm; and the operative condition of ischemia time are the most important predictors of clinical outcome after combined valve operations and coronary artery bypass grafting.     

Longterm followup (12-15 years) of a randomized controlled trial comparing Bassini-Stetten, Shouldice, and high ligation with narrowing of the internal ring for primary inguinal hernia repair

OBJECTIVE: To determine preoperative and perioperative risk factors for gastrointestinal (GI) complications following cardiac surgery. DESIGN: A database including records of patients who underwent cardiac surgery was reviewed, with univariate analysis of several variables thought to be relevant to GI complications. Using a risk-adjusted model, preoperative stratification was used to fit a logistic regression model including operative features. SETTING AND PATIENTS: All patients undergoing cardiac surgery from January 1, 1991, to December 31, 1994, at a university-affiliated teaching hospital. MAIN OUTCOME MEASURES: Incidence of GI complications, postoperative mortality, length of hospital stay, and relative risk of GI complications based on multivariate analyses. RESULTS: Gastrointestinal complications occurred in 2.1% of patients and had an associated mortality of 19.4%; this was higher than the mortality in patients without GI complications (4.1%; P < .001). Length of hospital stay was significantly longer in patients with GI complications (43 vs 13.4 days; P < .001). In patients who underwent coronary artery bypass grafting only, cardiopulmonary bypass time was significantly longer in patients with GI complications (166 vs 138 minutes; P = .004). In patients who underwent valve replacement, bypass time was not associated with GI complications. Use of a left internal mammary artery graft was associated with a lower incidence of GI complications. CONCLUSIONS: Patients who have GI complications after cardiac surgery have a higher mortality and a longer hospital stay. The use of a left internal mammary artery seems to have a protective effect against GI complications. Based on these observations, patients may be stratified into low-, medium-, and high-risk groups.     

Morbidity, cost, and six-month outcome of minimally invasive direct coronary artery bypass grafting

BACKGROUND: Minimally invasive direct coronary artery bypass grafting (MIDCABG) promises to reduce the morbidity of coronary bypass, but this has not been proved. METHODS: This retrospective study compares the morbidity, mortality, cost, and 6-month outcome of patients less than 80 years old undergoing elective left internal mammary artery to left anterior descending artery bypass grafting via MIDCABG (n = 60) or sternotomy (n = 55) between January 1995 and December 1996. There were no differences between the groups in mean age, sex distribution, or preoperative risk level. The left internal mammary artery was mobilized from the fifth costal cartilage to the subclavian artery in all patients. The anastomoses were done with a beating heart in the MIDCABG group and with cardioplegic arrest in the sternotomy group. RESULTS: There were no operative deaths in either group. The MIDCABG patients had a lower transfusion incidence (10/60 [17%] versus 22/55 [40%]; p< or =0.02) and a shorter postoperative intubation time (2.1+/-4.2 versus 12.6+/-9 hours; p< or =0.0001). One patient in each group was reexplored for bleeding. Three sternotomy patients (3/55, 5%) required ventilatory support for greater than 48 hours, but no MIDCABG patient was ventilated for more than 24 hours. Median postoperative length of stay was 4 days for MIDCABG and 7 days for sternotomy. Estimated hospital costs were $11,200+/-3100 for MIDCABG and $15,600+/-4200 for CABG (p < 0.001). The reduced morbidity and cost of MIDCABG was found mostly in high-risk patients. At 6-month follow-up, 5 MIDCABG patients (5/60, 8%) had evidence of recurrent ischemia involving the left anterior descending artery, primarily the result of anastomotic stricture. CONCLUSIONS: This analysis shows that MIDCABG reduces the initial morbidity and cost of coronary bypass, but some patients require subsequent reintervention. Long-term follow-up is needed before MIDCABG can be judged better than traditional bypass, but the initial results are promising, especially in high-risk patients.     

The risk of coronary artery surgery in women: a matched comparison using preoperative severity of illness scoring

OBJECTIVE: To evaluate the effect of gender on outcomes of coronary artery bypass surgery using a weighted preoperative severity of illness scoring system. DESIGN: Retrospective database review. SETTING: Tertiary care teaching hospital. PARTICIPANTS: The patient population consisted of 2,800 consecutive coronary artery bypass graft (CABG) patients (658 women, 2,142 men), with or without concurrent procedures, operated on between January 1, 1993 and March 31, 1994. MEASUREMENTS AND MAIN RESULTS: Patients were stratified for severity of illness using a 13-element scoring system. The distribution of severity of illness scores and severity of illness-stratified morbidity, hospital mortality, and intensive care unit (ICU) length of stay were compared by chi-square and Fischer's exact test where appropriate. Median duration of intubation and median duration of ICU length of stay were examined by the median test. Female versus male unadjusted mortality (4.9% v 3.0%), total morbidity (15.0% v 9.2%), and average initial ICU length of stay (92.62% v 60.56 hours) were statistically different. Female patients also had significantly more of the following postoperative morbidities: central nervous system complications (focal neurologic deficits, patients > or = 65 years 3.20% v 1.54%; global neurologic deficits, patients > or = 65 years 2.75% v 1.25%), duration of perioperative ventilation that includes the intubation time in the operating room until extubation in the ICU (average = 77.36 hours v 49.20 hours; median = 21.87 v 20.26 hours), and average initial ICU length of stay (average = 92.62 hours v 60.56 hours; median = 42.33 hours v 27.91 hours). However, distribution of severity scores was also different. Women had significantly more preoperative risk factors (p < 0.05): age 65 to 74 years (45.1% v 36.6%), age > or = 75 years (21.3% v 11.9%), chronic obstructive pulmonary disease (10.8% v 6.4%), hematocrit less than 34% (21.9% v 5.5%), diabetes (34.8% v 21.8%), weight less than 65 kg (37.4% v 6.2%), and operative mitral valve insufficiency (9.6% v 6.0%). Stratified by severity, no statistically significant gender differences were found for mortality, morbidity, or ICU length of stay. CONCLUSIONS: Gender does not appear to be an independent risk factor for perioperative morbidity, mortality, or excessive ICU length of stay when patients are stratified by preoperative risk in this severity of illness scoring system.     

Gastrointestinal complications after cardiac surgery

OBJECTIVE: Gastrointestinal (GI) complications after cardiac surgery with cardiopulmonary bypass (CPB) are uncommon complications with significant morbidity and mortality rates. METHODS: From 1988 to 1995, 36 GI complications were identified in 3158 patients who underwent cardiac surgery (1.14% incidence). The mortality rate was 13.9%. Complications included hemorrhage in the GI tract in 22, perforated ulcer in 3, acute cholecystitis in 3, pancreatitis in 2, mesenteric ischemia in 3, diverticulitis in 1 and liver failure in 2 patients. RESULTS: Clinical risk factors included advanced age, combined coronary artery bypass grafting (CABG)-valve operation, postoperative low cardiac output (LCO), prolonged ventilation time, re-exploration of the chest, sternal infection and a positive history of peptic ulcer. Patients with a prolonged pump time had an increased risk of GI complications (P < 0.001). CONCLUSIONS: Gastrointestinal complications, although of low incidence, carry a significantly high mortality, and the clinician must be alert to institute early appropriate treatment.     

Coronary artery bypass grafting in immune thrombocytopenic purpura

BACKGROUND: Reports of patients with idiopathic thrombocytopenic purpura undergoing cardiac operations are scarce and no recommendations exist regarding their management. We report 3 patients with idiopathic thrombocytopenic purpura and severe coronary artery disease who underwent uncomplicated coronary bypass grafting. METHODS: The case history of each patient with idiopathic thrombocytopenic purpura who underwent coronary artery bypass grafting and the literature were reviewed. RESULTS: All 3 patients underwent uncomplicated coronary artery bypass grafting after preoperative treatment with intravenous immunoglobulin and intraoperative platelet transfusions if needed. Prophylactic splenectomy was not performed. There was no increased incidence of bleeding complications. CONCLUSIONS: Coronary artery bypass grafting can be safely performed in patients with idiopathic thrombocytopenic purpura using conventional conduits after pretreating with immunoglobulin G and avoiding splenectomy.     

Emergency coronary surgery after failed angioplasty: 11 years of experience (1987-1997)

METHODS: From January 1987 to December 1997, thirty patients underwent emergent or urgent coronary artery bypass grafting after failed elective percutaneous transluminal coronary angioplasty. Dissection/occlusion of the target artery was the commonest complication, but we also had two cases of stent dislocation and one case of coronary artery wall perforation. Two-thirds of the patients experienced extreme preoperatory hemodynamic instability (i.e., cardiac arrest or cardiogenic shock) and half had to be intubated in the Catheterization Laboratory. An average of 1.73 grafts/patient was performed. Complete coronary revascularization was achieved in 93% of the cases; the internal mammary artery could be employed in one-third only. RESULTS: In-hospital mortality was 10%, and perioperatory myocardial infarction or persistent ischemia could be detected in half of the patients. The need for aortic counterpulsation, and the use of inotropic and antiarrhythmic drugs were higher than average in this group of patients; while intensive care unit and hospital stay were longer. Patients with deteriorated preoperative hemodynamics fared significantly worse. Late results were encouraging: seventy-five per cent of all patients (and 84% of hospital survivors) were still alive an average of 52 months after surgery. Two-thirds of all patients (and 72% of hospital survivors) were alive and angina-free. CONCLUSIONS: Even in the current era, revascularization surgery after failed coronary angioplasty still carries an increased risk for postoperative complications and death, especially for patients with deteriorated preoperative hemodynamic conditions. On the other hand, postoperative middle- and long-term results are encouraging, as hospital survivors were similar to elective bypass patients regarding survival and freedom from return of angina.     

A national study of postoperative mortality associated with coronary artery bypass grafting in Israel. ISCAB Consortium. Israel Coronary Artery Bypass Study

BACKGROUND: Investigation of observed differences in outcomes among medical centers is of major interest to the medical community and the public and has a substantial impact on efforts to improve the quality of medical care. METHODS: This study analyzed data from consecutive patients who underwent isolated coronary artery bypass grafting at 14 medical centers. Data included demographic and clinical information, comorbidity, cardiac catheterization results, and 30-day postoperative vitality status. Logistic regression analysis was used to identify variables associated with mortality. An outlier hospital was defined as one having an observed mortality outside the 95% confidence interval boundaries around the expected mortality rate calculated, given the patient risk factors. RESULTS: The overall crude 30-day mortality rate for isolated coronary artery bypass grafting among the 4,835 patients in this study was 3.1%. The rate varied among centers, ranging from 0.85% to 7.05%. Predictors of 30-day mortality included advanced age, female sex, diabetes mellitus, poor left ventricular function, high creatinine level, high priority of operation, and three-vessel disease (with or without left main coronary artery disease). After adjustment for risk factors, two hospitals were defined as outliers. CONCLUSIONS: The observed disparity in early mortality among patients undergoing coronary artery bypass grafting is not due solely to differences in case mix.     

Tracking the MEN1 gene

Combined carotid endarterectomy and coronary artery bypass grafting was performed in 52 patients between January 1982 and September 1994. Forty-nine patients had stable or unstable angina and three had symptom-free coronary artery disease detected by stress testing. Thirty-one patients had triple-vessel disease and 17 had left main trunk or left main equivalent coronary artery disease. Five patients had symptom-free carotid artery disease, 12 had non-specific neurological symptoms, and 35 had transient ischaemic attacks. Carotid endarterectomy was performed first, followed by coronary artery bypass grafting. There were three postoperative deaths, two cardiac and one neurological, for a mortality rate of 5.8%. One patient suffered a permanent neurological deficit (1.9%). It is concluded that combined carotid endarterectomy/coronary artery bypass grafting can be performed in selected patients with acceptable neurological morbidity, although cardiac mortality was not eliminated by the combined approach.     

Lipopolysaccharide activation of murine splenocytes and splenic B cells increased the expression of aryl hydrocarbon receptor and aryl hydrocarbon receptor nuclear translocator

BACKGROUND: To achieve complete myocardial revascularization in patients with diffuse coronary artery disease and patients at high risk if they undergo cardiopulmonary bypass such as severe systemic disease or diffuse arteriosclerosis of the aorta, we have adopted the technique of combining direct coronary artery bypass grafting without cardiopulmonary bypass with transmyocardial laser revascularization. METHODS: From April 1995 to September 1997 this technique was used in 77 patients. Ages ranged from 37 to 85 years with a mean of 56 +/- 17 years. Diffuse coronary artery lesions were present in 46 patients, 10 had severely deranged renal function, 7 had diffuse carotid artery lesions, and 7 had aortic arch atheromas. Liver dysfunction was present in 4 patients and severe obstructive airway disease in 3. The mean left ventricular ejection fraction was 0.45 +/- 0.05. Midsternotomy approach was used in 65 patients and anterior minithoracotomy in 12. Direct coronary artery bypass grafting without cardiopulmonary bypass was done to the left anterior descending coronary artery or right coronary artery or both. Transmyocardial laser revascularization using a 1,000-W CO2 laser machine was performed on the areas supplied by ungraftable coronary arteries or even in graftable distal targets in the posterolateral or inferior wall in patients who were at high risk if they underwent cardiopulmonary bypass. RESULTS: The mean number of vessels bypassed was 1.12. One patient died of intractable ventricular arrhythmia in the early postoperative phase. Mean follow-up was 16.6 months. At 12 months 89% of the patients were angina free. Metabolic stress test demonstrated an average increase in exercise tolerance from 5.2 at baseline to 9.7 minutes at 12 months. Myocardial thallium scanning done at 3-, 6-, and 12-month intervals postoperatively revealed that myocardial perfusion in grafted segments had an exponential trend of improvement, and perfusion in transmyocardial laser revascularization segments showed a linear trend in the same period with a total gain of 28.4%. CONCLUSIONS: Transmyocardial laser revascularization is an excellent adjunct to minimally invasive coronary artery bypass grafting to achieve complete myocardial revascularization in patients with graftable vessels in the anterior wall and ungraftable vessels in the posterior and inferior wall. This achieves complete myocardial revascularization without compromising safety in patients who are at high risk if they undergo cardiopulmonary bypass. Minimal morbidity and mortality in the present series revealed that this procedure is safe, and postoperative follow-up of these patients showed significant functional improvement as well as an improvement in myocardial perfusion scan.     

Minimally invasive treatment for coronary artery disease

Coronary artery disease is the leading cause of morbidity and mortality in the United States. One advancement in the treatment of this disease is the minimally invasive direct coronary artery bypass (MIDCAB) procedure, which is an alternative to the traditional open heart bypass procedure. The MIDCAB procedure is becoming a viable alternative to the traditional coronary artery bypass grafting procedure for a select group of patients. With further experience and follow-up, this procedure will offer lower hospital costs by decreasing lengths of stay and offering patients the optimal conduit for coronary artery bypass grafting without the complications of cardiopulmonary bypass.     

Influence of ejection fraction on hospital mortality, morbidity, and costs for CABG patients

BACKGROUND: Preoperative ejection fraction (EF) has been shown to adversely affect postoperative hospital mortality and morbidity for patients undergoing isolated coronary artery bypass grafting. METHODS: To investigate influence of EF on isolated coronary artery bypass grafting outcomes (overall hospital mortality, hospital cardiac mortality, hospital morbidity, and hospital costs), data were reviewed from 1,354 consecutive patients who underwent isolated coronary artery bypass grafting between January 1, 1990, and April 30, 1992, at a single nonprofit hospital. Overall hospital mortality was 4.06% (cardiac, 2.36%). Hospital morbidity was 14.25% (including mortality). Hospital costs (not charges) averaged $16,673 per patient. To explore the impact of preoperative EF, EF was stratified into regular intervals. Each interval was then compared with regard to hospital mortality, morbidity, and average costs. A new statistical tool, discharge analysis, was developed to analyze the cost data. This was necessary because previous efforts at cost analysis have used tools inappropriate for real world cost data. RESULTS: The statistical analysis showed that patients with EF of 0.40 or greater had the best outcomes (lowest mortality, morbidity, and cost). Once the EF is 0.40 or greater the EF does not carry further predictive value. At EF less than 0.40, patients with EF less than 0.30 have a poorer outcome than patients with EF of 0.30 to 0.39. CONCLUSIONS: (1) Ejection fraction is a valid predictor of mortality, morbidity and resource utilization based on statistical analysis. (2) Patients can be broadly grouped as having EF greater than 0.40, less than 0.30, or from 0.30 to 0.39 with regard to clinical and cost outcomes. (3) Postoperative length of stay is not predicted by risk-adjusted EF. (4) A new tool, discharge analysis, is presented to facilitate cost analysis.     

Operative outcome and hospital cost

INTRODUCTION: Because of concern about increasing health care costs, we undertook a study to find patient risk factors associated with increased hospital costs and to evaluate the relationship between increased cost and in-hospital mortality and serious morbidity. METHODS: More than 100 patient variables were screened in 1221 patients undergoing cardiac procedures. Simultaneously, patient hospital costs were computed from the cost-to-charge ratio. Univariate and multivariate statistics were used to explore the relationship between hospital cost and patient outcomes, including operative death, in-hospital morbidity, and length of stay. RESULTS: The greatest costs were for 31 patients who did not survive operation ($74,466, 95% confidence interval $27,102 to $198,025), greater than the costs for 120 patients who had serious, nonfatal morbidity ($60,335, 95% confidence interval $28,381 to $130,897, p = 0.02) and those for 1070 patients who survived operation without complication ($31,459, 95% confidence interval $21,944 to $49,849, p = 0.001). Breakdown of the components of hospital costs in fatalities and in cases with nonfatal complications revealed that the greatest contributions were in anesthesia and operating room costs. Significant (by stepwise linear regression analysis) independent risks for increased hospital cost were as follows (in order of decreasing importance): (1) preoperative congestive heart failure, (2) serum creatinine level greater than 2.5 mg/dl, (3) New York state predicted mortality risk, (4), type of operation (coronary artery bypass grafting, valve, valve plus coronary artery bypass grafting, or other), (5) preoperative hematocrit, (6) need for reoperative procedure, (7) operative priority, and (8) sex. These risks were different than those for in-hospitality death or increased length of stay. Hospital cost correlated with length of stay (r = 0.63, p < 0.001), but there were many outliers at the high end of the hospital cost spectrum. CONCLUSIONS: We conclude that operative death is the most costly outcome; length of stay is an unreliable indicator of hospital cost, especially at the high end of the cost spectrum; risks of increased hospital cost are different than those for perioperative mortality or increased length of stay; and ventricular dysfunction in elderly patients undergoing urgent operations for other than coronary disease is associated with increased cost. Certain patient factors, such as preoperative anemia and congestive heart failure, are amenable to preoperative intervention to reduce costs, and a high-risk patient profile can serve as a target for cost-reduction strategies.     

Surgical treatment of ischemic heart disease complicated with severe left ventricular dysfunction: experience in 200 cases

BACKGROUND: The study was designed to evaluate short and long-term benefits of coronary artery bypass graft in patients with coronary artery disease and severely depressed left ventricular ejection fraction and to identify contemporary risk factors associated with significantly greater mortality in this high-risk subgroup. METHODS: From 1985 to 1995, 200 consecutive pts with EF < or = 0.30 underwent CABG. Among these patients, 60% were older than 70 years. NYHA functional class III/IV was present in 31% of pts. Preoperative mean cardiac index was 2.7 +/- 7 l/min/m2, mean pulmonary artery pressure was 29.9 +/- 7 mm Hg and contractility score (generated by appropriate software for left ventricular kinesis analysis) mean value was 50.1 +/- 11.6 points. Urgent operation was required in 32 pts (16%). The majority of pts were completely revascularized. RESULTS: Operative mortality was 9% (18 pts). Low output syndrome was the most common postoperative complication (13.5%) followed by ventricular arrhythmia (8%), mean length of postoperative hospitalization for survivors was 13 +/- 10 days. Of 23 possible operative risk factors evaluated, four were associated with significantly greater mortality: cardiac index < or = 2.1 l/min/m2, urgent operation, contractility score > or = 80 and associated surgical procedures. Survivors experienced significant improvement in CHF class (p < 0.001) and follow up EF (p < 0.001). Kaplan-Meier estimate of survival at 1 year, 5 years and 8 years was 85%, 65% and 54%. CONCLUSION: Through more careful assessment of preoperative risk factors, patients selection and perioperative management, actually coronary artery bypass graft may be offered to pts with low ejection fraction with reduced morbidity and mortality.     

Extensive endarterectomy of the left anterior descending coronary artery combined with coronary artery bypass grafting

BACKGROUND: Complete revascularization of a diffusely diseased left anterior descending (LAD) coronary artery can be accomplished by extensive endarterectomy in conjunction with coronary artery bypass grafting (CABG). The present study was designed to assess the safety of the procedure, and which techniques lead to the best short- and long-term results. METHODS: Between January 1990 and October 1994 106 patients underwent extensive open endarterectomy of the LAD coronary artery combined with CABG at our institution. This group constituted 4.9% of all patients undergoing CABG during this period. The mean age of those studied was 64.4 +/- 9.2 years and 92% were male. In 22 patients (21%) the procedure was a repeat CABG and 12% had had percutaneous transluminal coronary angioplasty prior to the operation. Ninety-one per cent of the patients were in Canadian Cardiovascular Society (CCS) angina class 3 or 4, 91% had three-vessel disease and 36% had unstable angina at the time of surgery. The mean preoperative left ventricular ejection fraction was 53.6 +/- 14.9% (range, 15-80%). The internal mammary artery (IMA) was used to bypass the LAD coronary artery in 40 patients (38%) and a saphenous vein graft (SVG) was used in 66 patients. In 25 of the IMA bypass group an additional venous patch was used (IMA+P). RESULTS: The overall mortality rate was 9.4% (10 patients), including seven immediate postoperative deaths. When the IMA was used as a conduit the mortality rate was only 5.0%. There were seven (6.6%) postoperative non-fatal myocardial infarctions. There was a low incidence of other postoperative complications, similar to that following CABG without endarterectomy performed during the same period. Multivariate analysis identified emergency operation, two-vessel endarterectomy and female sex as independent risk factors for mortality. Upon follow-up study of 94 hospital survivors (98%), at a mean of 26.5 months (range, 1-48 months), all endarterectomy patients were in CCS class 1 or 2. Seventy-eight patients (83%) had an excellent postoperative exercise tolerance and the left ventricular function was preserved. The 4-year survival rates were 88% and 96% and the cardiac event-free survival rates were 74% and 87% in the SVG and IMA groups respectively. CONCLUSIONS: Complete revascularization of the diffusely diseased LAD coronary artery can be accomplished by adjunctive open endarterectomy with a degree of operative risk (mortality 9% and incidence of non-fatal myocardial infarction 7%). The immediate and medium-term results are improved when the IMA is used as a conduit, with or without additional venous patch. Independent risk factors for mortality were two-vessel endarterectomy, female sex and emergency operation. The long-term results revealed an overall survival rate of 92% and a cardiac event-free survival rate of 79% at 4 years, as well as excellent functional results.