Cardiac Surgical Mortality Research Articles

Comparative Results of Combined Coronary Artery Bypass Grafting and Carotid Endarterectomy versus Staged Operation

Purpose: Between combined and staged operations of carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG) for patients with concurrent coronary and carotid disease, each treatment strategy has its own advantages and disadvantages. We attempted to compare early surgical results between the two operations. Methods: We retrospectively reviewed medical records of 71 patients who underwent either combined CEA & CABG (n=37) or staged CABG & CEA (n=34) in a single institute between January 2001 and March 2010. After comparing patients’ demographics and preoperative neurologic and cardiac status, we compared early (＜1 month) postoperative cardiac or neurologic complications and surgical mortality between the 2 groups. Results: There was no significant difference in patients’ demographics and indications for operation the between 2 groups. There were 2 (5.4%) cases of postoperative stroke in combined groups and 1 (2.9%) in staged group. However, there was no myocardial infarction or death. In staged operation group, during the interval time between the two operations, 5 cases (14.7%) of stroke developed, of which, all patients recovered without any sequelae by anticoagulation. Conclusion: After experiencing low postoperative cardiac or neurologic morbidity or mortality after combined CABG and CEA, we conclude that combined CABG and CEA was a safe and feasible treatment option for patients with neurologic symptoms and in stable cardiac status. In the staged operation group of patients, we observed development of neurologic events during the interval period between CABG and CEA. To attain optimal treatment strategy in asymptomatic patients, further prospective study would be required.

The Children’s Hospital Boston Non-Routine Event Reporting Program

Several authors have described methods to track perfusion and cardiac surgical morbidity and mortality as well as perfusion accidents. There is currently not a standard definition of a perfusion accident nor is there a standard reporting threshold for events which do not directly cause known morbidity. We propose the term non-routine events (NREs) instead of accidents, and provide a working definition and reporting threshold for such. This paper describes the program which we developed to track perfusion NREs within the Cardiovascular Program at Children’s Hospital, Boston. NREs are categorized by type (technique, equipment, or patient-related) and bypass period (pre-cardiopulmonary bypass, bypass, or post-cardiopulmonary). NRE outcomes are also classified by the level of discussion or change in perfusion practice after multidisciplinary review. We have documented during a 44 month interval that 42% (29/69) of reported NREs occur during the bypass period and are equipment related and thus, efforts to improve practice should focus there. We have also seen a generally decreasing incidence of NREs requiring either a change in perfusion practice or a new protocol during this time period. We believe that our regular multidisciplinary meetings to discuss NREs have increased awareness among the entire team about potential problems in the program and that intuitively, it has improved patient safety.

The complex relationship between pediatric cardiac surgical case volumes and mortality rates in a national clinical database

We sought to determine the association between pediatric cardiac surgical volume and mortality using sophisticated case-mix adjustment and a national clinical database. Patients 18 years of age or less who had a cardiac operation between 2002 and 2006 were identified in the Society of Thoracic Surgeons Congenital Heart Surgery Database (32,413 patients from 48 programs). Programs were grouped by yearly pediatric cardiac surgical volume (small, <150; medium, 150-249; large, 250-349; and very large, >or=350 cases per year). Logistic regression was used to adjust mortality rates for volume, surgical case mix (Aristotle Basic Complexity and Risk Adjustment for Congenital Heart Surgery, Version 1 categories), patient risk factors, and year of operation. With adjustment for patient-level risk factors and surgical case mix, there was an inverse relationship between overall surgical volume as a continuous variable and mortality (P = .002). When the data were displayed graphically, there appeared to be an inflection point between 200 and 300 cases per year. When volume was analyzed as a categorical variable, the relationship was most apparent for difficult operations (Aristotle technical difficulty component score, >3.0), for which mortality decreased from 14.8% (60/406) at small programs to 8.4% (157/1858) at very large programs (P = .02). The same was true for the subgroup of patients who underwent Norwood procedures (36.5% [23/63] vs 16.9% [81/479], P < .0001). After risk adjustment, all groups performed similarly for low-difficulty operations. Conversely, for difficult procedures, small programs performed significantly worse. For Norwood procedures, very large programs outperformed all other groups. There was an inverse association between pediatric cardiac surgical volume and mortality that became increasingly important as case complexity increased. Although volume was not associated with mortality for low-complexity cases, lower-volume programs underperformed larger programs as case complexity increased.

Cardiac Surgery in the Parturient

Heart disease is the primary cause of nonobstetric mortality in pregnancy, occurring in 1%-3% of pregnancies and accounting for 10%-15% of maternal deaths. Congenital heart disease has become more prevalent in women of childbearing age, representing an increasing percentage (up to 75%) of heart disease in pregnancy. Untreated maternal heart disease also places the fetus at risk. Independent predictors of neonatal complications include a maternal New York Heart Association heart failure classification >2, anticoagulation use during pregnancy, smoking, multiple gestation, and left heart obstruction. Because cardiac surgical morbidity and mortality in the parturient is higher than nonpregnant patients, most parturients with cardiac disease are first managed medically, with cardiac surgery being reserved when medical management fails. Risk factors for maternal mortality during cardiac surgery include the use of vasoactive drugs, age, type of surgery, reoperation, and maternal functional class. Risk factors for fetal mortality include maternal age >35 yr, functional class, reoperation, emergency surgery, type of myocardial protection, and anoxic time. Nonetheless, acceptable maternal and fetal perioperative mortality rates may be achieved through such measures as early preoperative detection of maternal cardiovascular decompensation, use of fetal monitoring, delivery of a viable fetus before the operation and scheduling surgery on an elective basis during the second trimester. Additionally, fetal morbidity may be reduced during cardiopulmonary bypass by optimizing maternal oxygen-carrying capacity and uterine blood flow. Current maternal bypass recommendations include: 1) maintaining the pump flow rate >2.5 L x min(-1) x m(-2) and perfusion pressure >70 mm Hg; 2) maintaining the hematocrit > 28%; 3) using normothermic perfusion when feasible; 4) using pulsatile flow; and 5) using alpha-stat pH management.

Comparison of Pediatric Cardiac Surgical Mortality Rates From National Administrative Data to Contemporary Clinical Standards

Despite the superior coding and risk adjustment of clinical data, the ready availability, national scope, and perceived unbiased nature of administrative data make it the choice of governmental agencies and insurance companies for evaluating quality and outcomes. We calculated pediatric cardiac surgery mortality rates from administrative data and compared them with widely quoted standards from clinical databases. Pediatric cardiac surgical operations were retrospectively identified by ICD-9-CM diagnosis and procedure codes from the Nationwide Inpatient Sample (NIS) 1988-2005 and the Kids' Inpatient Database (KID) 2003. Cases were grouped into Risk Adjustment for Congenital Heart Surgery, version 1 (RACHS-1) categories. In-hospital mortality rates and 95% confidence intervals were calculated. A total of 55,164 operations from the NIS and 10,945 operations from the KID were placed into RACHS-1 categories. During the 18-year period, the overall NIS mortality rate for pediatric cardiac surgery decreased from 8.7% (95% confidence interval, 8.0% to 9.3%) to 4.6% (95% confidence interval, 4.3% to 5.0%). Mortality rates by RACHS-1 category decreased significantly as well. The KID and NIS mortality rates from comparable years were similar. Overall mortality rates derived from administrative data were higher than those from contemporary national clinical data, The Society of Thoracic Surgeons Congenital Heart Surgery Database, or published data from pediatric cardiac specialty centers. Although category-specific mortality rates were higher in administrative data than in clinical data, a minority of the relationships reached statistical significance. Despite substantial improvement, mortality rates from administrative data remain higher than those from clinical data. The discrepancy may be attributable to several factors: differences in database design and composition, differences in data collection and reporting structures, and variation in data quality.

Risk Factors and Outcome in Iranian Cardiac Surgery: Iranian Heart Score

Coronary artery bypass grafting (CABG) is one of the leading operations performed worldwide. This treatment modality has been performed in Iran for several years; however, little is known about the current risk profile of Iranian cardiac surgical patients. The authors investigated the relationship between risk factors and mortality assessed by logistic regression analysis. The final Iranian risk stratification model consists of 15 variables, including sex, age, preoperative ejection fraction, chronic renal failure, recent myocardial infarction, unstable angina, preoperative critical situation, run off of left anterior descending artery, indications for surgery, CABG + mitral valve replacement, CABG + aortic valve replacement, postoperational myocardial infarction, postoperational low cardiac output, prolonged intubation, and central nervous system complication. A number of risk factors contribute to cardiac surgical mortality in Iran, which is used to develop a risk stratification system for predication of hospital mortality and the assessment of quality of care.

Paediatric cardiac surgical mortality in England after Bristol: descriptive analysis of hospital episode statistics 1991-2002

Objective To describe trends in mortality of open cardiac surgery in children in Bristol and England since 1991.Design Retrospective analysis of hospital episode statistics data.Setting All open cardiac surgery of...

Calcium antagonists are associated with reduced mortality after cardiac surgery: a propensity analysis

Objectives Observational studies have questioned the effectiveness of perioperative calcium channel blockers but failed to correct for selection biases. We therefore performed a prospective observational cohort study of the effects of calcium channel blockers on cardiac surgical mortality. A propensity score technique was used for risk adjustment. Methods We identified 6619 patients who underwent nontransplant cardiac surgery at the Toronto General Hospital (Toronto, Ontario, Canada) between May 1999 and December 2001. Propensity scores for calcium channel blocker use were constructed for the entire sample and for the subgroup (n = 5222) that underwent coronary artery bypass grafting. The calcium channel blocker adjusted odds ratio for in-hospital mortality after cardiac surgery was determined by using multiple logistic regression and propensity matched-pairs analyses. A subgroup analysis was performed for patients who underwent coronary artery bypass grafting: the calcium channel blocker adjusted odds ratio for mortality was determined by using propensity score matched-pairs analyses. Results Calcium channel blockers were associated with significantly reduced cardiac surgical mortality after adjustment with both multiple logistic regression (odds ratio, 0.56; 95% confidence interval, 0.33-0.94; P = .028) and propensity score matched-pairs analyses (odds ratio, 0.56; 95% confidence interval, 0.32-0.98; P = .042). Calcium channel blockers were also associated with reduced mortality (odds ratio, 0.48; 95% confidence interval, 0.23-0.98; P = .044) among patients who underwent coronary artery bypass grafting. Conclusions After adjustment for baseline differences, calcium channel blockers were associated with significantly reduced mortality after cardiac surgery. This benefit also extends to the subgroup that underwent coronary artery bypass grafting. A large randomized controlled trial of perioperative calcium channel blockers is therefore warranted.

The relationship between predicted and actual cardiac surgical mortality: impact of risk grouping and individual surgeons.

To study the relationship between predicted and actual mortality in a cardiac surgical practice and to determine whether there is a consistent relationship across risk groups and surgeons. Risk information (Parsonnet score) was prospectively collected for 6213 consecutive adult patients undergoing cardiac surgery at one institution. The relationship between predicted mortality and actual mortality was analysed by risk group for all patients and for individual surgeons' practices. Predicted mortality was 10.2%. Actual mortality was 4.2%, giving a mortality ratio of 41% of predicted. This ratio was not consistent across the five major risk groups, ranging from 32% in moderate risk to 67% in very low risk patients. When analysed by individual surgical practices, the results were even more disparate, with a mortality index range between 0% for one surgeon's low risk patients to 150% for another surgeon's very low risk patients. The relationship between predicted and actual mortality at one institution may vary across the risk spectrum and between surgeons. This should be taken into account in preoperative risk assessment and informed patient consent. Individual surgeons may have strengths and weaknesses which are related to preoperative risk stratification.

The safety of intraoperative transesophageal echocardiography: a case series of 7200 cardiac surgical patients.

Transesophageal echocardiography (TEE) is an invaluable intraoperative diagnostic monitor that is considered to be relatively safe and noninvasive. Insertion and manipulation of the TEE probe, however, may cause oropharyngeal, esophageal, or gastric trauma. We report the incidence of intraoperative TEE-associated complications in a single-center series of 7200 adult cardiac surgical patients. Information related to intraoperative TEE-associated complications was obtained retrospectively from the intraoperative TEE data form, routine postoperative visits, and cardiac surgical morbidity and mortality data. The overall incidences of TEE-associated morbidity and mortality in the study population were 0.2% and 0%, respectively. The most common TEE-associated complication was severe odynophagia, which occurred in 0.1% of the study population. Other complications included dental injury (0.03%), endotracheal tube malpositioning (0.03%), upper gastrointestinal hemorrhage (0.03%), and esophageal perforation (0.01%). TEE probe insertion was unsuccessful or contraindicated in 0.18% and 0.5% of the study population, respectively. These data suggest that intraoperative TEE is a relatively safe diagnostic monitor for the management of cardiac surgical patients. The overall morbidity (0.2%) and mortality (0%) rates of intraoperative transesophageal echocardiography (TEE) were determined in a retrospective case series of 7200 adult, anesthetized cardiac surgical patients. The most common source of TEE-associated morbidity was odynophagia (0.1%), which resolved with conservative management. These results suggest that TEE is a safe diagnostic tool for the management of cardiac surgical patients.

High lactate predicts the failure of intraaortic balloon pumping after cardiac surgery

Background. Despite the use of intraaortic balloon pump (IABP) support in complex cardiac surgical patients, morbidity and mortality rates are high. More advanced mechanical cardiovascular support should be considered in those patients who are highly likely to die despite IABP support. We sought to identify early, readily available prognostic markers for patients receiving IABP support.Methods. A retrospective analysis was performed on 39 patients requiring IABP support following cardiac surgery for more than 2 years. The accuracy and predictive ability of multiple potential markers of mortality were statistically assessed.Results. Sixty-seven percent of the patients were successfully weaned from IABP support and 46% survived to hospital discharge. Serious complications occurred in 13% of patients. Serum lactate more than 10 mmol/L in the first 8 hours of IABP support predicted a 100% mortality. Base deficit more than 10 mmol/L, mean arterial pressure less than 60 mm Hg, urine output less than 30 mls/h for 2 hours, and dose of epinephrine or norepinephrine more than 10 μg/min were other highly predictive prognostic markers.Conclusions. Morbidity and mortality rates remain high despite IABP support following cardiac surgery. Mortality can be predicted by the presence of elevated serum lactate, elevated base deficit, hypotension, oliguria and large vasopressor doses, any of which should prompt appropriate consideration as to other mechanical cardiovascular support.

Risk factors and outcome in European cardiac surgery: analysis of the EuroSCORE multinational database of 19030 patients.

To assess risk factors for mortality in cardiac surgical adult patients as part of a study to develop a European System for Cardiac Operative Risk Evaluation (EuroSCORE). From September to November 1995, information on risk factors and mortality was collected for 19030 consecutive adult patients undergoing cardiac surgery under cardiopulmonary bypass in 128 surgical centres in eight European states. Data were collected for 68 preoperative and 29 operative risk factors proven or believed to influence hospital mortality. The relationship between risk factors and outcome was assessed by univariate and logistic regression analysis. Mean age (+/- standard deviation) was 62.5+/-10.7 (range 17-94 years) and 28% were female. Mean body mass index was 26.3+/-3.9. The incidence of common risk factors was as follows: hypertension 43.6%, diabetes 16.7%, extracardiac arteriopathy 2.9%, chronic renal failure 3.5%, chronic pulmonary disease 3.9%, previous cardiac surgery 7.3% and impaired left ventricular function 31.4%. Isolated coronary surgery accounted for 63.6% of all procedures, and 29.8% of patients had valve operations. Overall hospital mortality was 4.8%. Coronary surgery mortality was 3.4% In the absence of any identifiable risk factors, mortality was 0.4% for coronary surgery, 1% for mitral valve surgery, 1.1% for aortic valve surgery and 0% for atrial septal defect repair. The following risk factors were associated with increased mortality: age (P = 0.001), female gender (P = 0.001), serum creatinine (P = 0.001), extracardiac arteriopathy (P = 0.001), chronic airway disease (P = 0.006), severe neurological dysfunction (P = 0.001), previous cardiac surgery (P = 0.001), recent myocardial infarction (P = 0.001), left ventricular ejection fraction (P = 0.001), chronic congestive cardiac failure (P = 0.001), pulmonary hypertension (P = 0.001), active endocarditis (P = 0.001), unstable angina (P = 0.001), procedure urgency (P = 0.001), critical preoperative condition (P = 0.001) ventricular septal rupture (P = 0.002), noncoronary surgery (P = 0.001), thoracic aortic surgery (P = 0.001). A number of risk factors contribute to cardiac surgical mortality in Europe. This information can be used to develop a risk stratification system for the prediction of hospital mortality and the assessment of quality of care.

Congenital heart disease in patients over 40 years old who have not undergone cardiac surgery.

The histories and medical courses were reviewed in 154 patients with congenital heart disease (CHD) ranged in age 40 to 77 years (mean 48.8 years) who had not yet undergone cardiac surgery. The CHD most commonly involved were atrial septal defect (ASD)(63.6%), ventricular septal defect (13.6%) and patent ductus arteriosus (8.4%). There were no cases of tetralogy of Fallot or of transposition of the great arteries in this study. Hemodynamic observations showed no significant correlation between the age and systolic pulmonary artery pressure in left-to-right shunt disease. Mortality due to cardiac failure was higher in patients whose systolic pulmonary artery pressure was over 50 mmHg. 91 patients had cardiac surgery and surgical mortality was 7% (6 patients). There was one late ASD death, and 46% are in good condition (NYHA I). In patients without surgery, 27% (17 patients) died of cardiac failure except one, and 11% (6 patients) are in good condition. Among factors affecting prognosis, pulmonary vascular changes are the most important, with arrhythmia and myocardial damage occurring with age, and complications like infective endocarditis and coronary sclerosis affecting prognosis adversely.