The Perception of Evidence for Venous Thromboembolism Prophylaxis Current Practices after Cardiac Surgery: A Canadian Cross-Sectional Survey.

Background. Venous thromboembolism (VTE) is the third leading cause of cardiovascular death in patients undergoing surgery. However, VTE prophylaxis practices in cardiac surgery are based on noncardiac surgical literature. The objective of our study was to extract current patterns of VTE prophylaxis practices in cardiac surgery patients. We also aimed to identify health care professionals knowledge of available evidence supporting VTE prophylaxis in adult cardiac surgery patients. Methods. A web-based survey was developed and sent to all Canadian cardiac surgery centers with the intent to have the survey distributed to all personnel involved in the perioperative care of adult cardiac surgery patients. Participation in the questionnaire was voluntary and anonymized. Results. Thirty-five responses were obtained. Sixty-nine percent reported having an established protocol for VTE prophylaxis. However, 83% reported using VTE prophylaxis in their daily practice despite lack of protocol. The majority (60%) believed that the class of recommendation was high despite the lack of evidence. Conclusions. Our survey demonstrated the following. (a) Majority of Canadian centers employ VTE prophylaxis, with considerable variability. (b) There is a misconception among health care professionals about the strength of evidence supporting VTE prophylaxis in cardiac surgery. Our findings highlight the need for appropriately designed studies to fill this knowledge gap.

A pilot randomized controlled trial comparing CABG surgery performed with total arterial grafts or without.

OBJECTIVE: To date only a few randomized controlled studies have compared grafting strategies in patients with multi-vessel coronary disease. This study represents a pilot RCT designed to test the feasibility of a trial comparing conventional CABG performed with a LIMA-LAD plus saphenous vein grafts (LIMA+SVG) and CABG performed with total arterial grafting (TAG). METHODS: Consenting patients undergoing non-redo isolated CABG surgery at a single institution were randomized to TAG or LIMA+SVG groups. Exclusion criteria included prior CABG, emergent procedure, concomitant procedure, varicose veins and renal dysfunction. The primary endpoints were: enrolment >20% and completion of CT coronary angiography at 6 months >80%. Statistical investigation was performed on an intention to treat analysis. RESULTS: Of 421 eligible patients, 60 were enrolled and 2 withdrew (n = 30 in TAG, n = 28 LIMA+SVG) for 14% enrolment rate. Patient characteristics were similar in each group. No patients died in hospital and adverse events such as MI, stroke and deep sternal wound infection were not significantly different between groups. Clinical follow-up was complete in 100% of patients, with 44/58 (76%) undergoing CT coronary angio at 6 months. Graft occlusion occurred in 2 patients in each group for patency rates of 89% (TAG) and 91% (LIMA+SVG). CONCLUSIONS: We provide evidence that an RCT comparing grafting strategy is possible but also show that achieving recruitment or follow-up CT may be difficult. Given the excellent patency results and little difference between groups, our findings suggest that the sample size required may make it infeasible to compare graft patency at 6 months as a study end-point. TRIAL REGISTRATION: Randomized Controlled Trial number: ISRCTN80270323 . Few RCT's exist comparing conventional CABG performed with a LIMA-LAD plus saphenous vein grafts (LIMA+SVG) compared to CABG performed with total arterial grafting (TAG). This study is a pilot RCT designed to test the feasibility of such a trial and identify pitfalls.

Prevalence of and risk factors for persistent postoperative nonanginal pain after cardiac surgery: a 2-year prospective multicentre study.

BACKGROUND: Persistent postoperative pain continues to be an underrecognized complication. We examined the prevalence of and risk factors for this type of pain after cardiac surgery. METHODS: We enrolled patients scheduled for coronary artery bypass grafting or valve replacement, or both, from Feb. 8, 2005, to Sept. 1, 2009. Validated measures were used to assess (a) preoperative anxiety and depression, tendency to catastrophize in the face of pain, health-related quality of life and presence of persistent pain; (b) pain intensity and interference in the first postoperative week; and (c) presence and intensity of persistent postoperative pain at 3, 6, 12 and 24 months after surgery. The primary outcome was the presence of persistent postoperative pain during 24 months of follow-up. RESULTS: A total of 1247 patients completed the preoperative assessment. Follow-up retention rates at 3 and 24 months were 84% and 78%, respectively. The prevalence of persistent postoperative pain decreased significantly over time, from 40.1% at 3 months to 22.1% at 6 months, 16.5% at 12 months and 9.5% at 24 months; the pain was rated as moderate to severe in 3.6% at 24 months. Acute postoperative pain predicted both the presence and severity of persistent postoperative pain. The more intense the pain during the first week after surgery and the more it interfered with functioning, the more likely the patients were to report persistent postoperative pain. Pre-existing persistent pain and increased preoperative anxiety also predicted the presence of persistent postoperative pain. INTERPRETATION: Persistent postoperative pain of nonanginal origin after cardiac surgery affected a substantial proportion of the study population. Future research is needed to determine whether interventions to modify certain risk factors, such as preoperative anxiety and the severity of pain before and immediately after surgery, may help to minimize or prevent persistent postoperative pain.

Mitral valve and short-term ventricular assist devices; potential mechanical complications.

Mechanical complications of ventricular assist devices (VADs) are rare but serious. The authors describe two cases of different mechanical complications of VADs that can affect the mitral valve. Attention should be paid to the position of the inflow/outflow cannula after off-loading of the ventricle, especially in acute heart failure and normal atrial dimensions. Complete off-loading of the left ventricle in the presence of a bioprosthetic mitral valve might cause fusion of the valve leaflets leading to mitral stenosis, which will call for another intervention.

Delirium: a cause for concern beyond the immediate postoperative period.

BACKGROUND: Delirium is a common neurologic complication after cardiac surgery, and may be associated with increased morbidity and mortality. Research has focused on potential causes of delirium, with little attention to its sequelae. METHODS: Perioperative data were collected prospectively on all isolated cases of coronary artery bypass grafting (CABG) performed from 1995 to 2006 at a single center. The definition of delirium used in the study was that of the Society of Thoracic Surgeons. Characteristics of patients who became delirious postoperatively were compared with those of patients who did not. The outcomes of interest were long-term all-cause mortality, hospital admission for stroke, and in-hospital mortality, examined in all three cases through multivariate analysis. RESULTS: Of 8,474 patients who underwent CABG within the defined period, 496 (5.8%) developed postoperative delirium and 229 (2.7%) died while in the hospital. At baseline, patients who developed delirium were more likely to be older and to have a greater burden of comorbid illness. Delirium was an independent predictor of perioperative stroke (odds ratio [OR]; 1.96; 95% confidence interval [CI], 1.22 to 3.16), but was not associated with in-hospital mortality (OR, 0.81; 95%CI, 0.49 to 1.34). Delirious patients had a median postoperative hospital stay of 12 days (interquartile range [IQR], 8 to 21 days) versus 6 days (IQR, 5 to 8 days) for those who were nondelirious. Delirium was identified as an independent predictor of all-cause mortality (hazard ratio [HR], 1.52; 95%CI, 1.29 to 1.78) and hospitalization for stroke (HR, 1.54; 95%CI, 1.10 to 2.17). CONCLUSIONS: There was an association between delirium and adverse outcomes after CABG that persisted beyond the immediate perioperative period. Patients with delirium after CABG appear to have an increased long-term risk of death and stroke. The advancing age and rising rates of delirium in the CABG population make it necessary to address the prevention and management of delirium in this population.

Should all patients be treated with an angiotensin-converting enzyme inhibitor after coronary artery bypass graft surgery? The impact of angiotensin-converting enzyme inhibitors, statins, and ß-blockers after coronary artery bypass graft surgery.

BACKGROUND: We sought to evaluate the association between angiotensin-converting enzyme (ACE) inhibitors and outcomes after coronary artery bypass graft surgery (CABG). METHODS: Postoperative outpatient utilization of ACE inhibitors, statins, and ß-blockers was assessed in a cohort of 3,718 patients after CABG 65 years and older. The primary outcome was freedom from a composite of all-cause mortality or hospital readmission for cardiac events or procedures. RESULTS: Use of all 3 medication classes increased significantly over the study period. Female patients and patients with a history of myocardial infarction, diabetes, and poor left ventricular function were independently associated with ACE inhibitor use on multivariate analysis (all P < .05). At a median follow-up of 3 years, postoperative therapy with an ACE inhibitor had no effect on death or rehospitalization for cardiovascular events (adjusted hazard ratio [HR] 1.12, 95% CI 0.96-1.30, P = .16). However, statins (HR 0.65, 95% CI 0.57-0.74, P < .0001) and ß-blockers (HR 0.83, 95% CI 0.74-0.93, P = .001) were associated with a significantly improved event-free survival. CONCLUSIONS: Among patients after CABG 65 years or older, ACE inhibitors had no independent effect on mortality or recurrent ischemic events in the midterm after CABG, although a benefit was observed for statins and ß-blockers.

Delirium as a predictor of sepsis in post-coronary artery bypass grafting patients: a retrospective cohort study.

INTRODUCTION: Delirium is the most common neurological complication following cardiac surgery. Much research has focused on potential causes of delirium; however, the sequelae of delirium have not been well investigated. The objective of this study was to investigate the relationship between delirium and sepsis post coronary artery bypass grafting (CABG) and to determine if delirium is a predictor of sepsis. METHODS: Peri-operative data were collected prospectively on all patients. Subjects were identified as having agitated delirium if they experienced a short-term mental disturbance marked by confusion, illusions and cerebral excitement. Patient characteristics were compared between those who became delirious and those who did not. The primary outcome of interest was post-operative sepsis. The association of delirium with sepsis was assessed by logistic regression, adjusting for differences in age, acuity, and co-morbidities. RESULTS: Among 14,301 patients, 981 became delirious and 227 developed sepsis post-operatively. Rates of delirium increased over the years of the study from 4.8 to 8.0% (P = 0.0003). A total of 70 patients of the 227 with sepsis, were delirious. In 30.8% of patients delirium preceded the development of overt sepsis by at least 48 hours. Multivariate analysis identified several factors associated with sepsis, (receiver operating characteristic (ROC) 79.3%): delirium (odds ratio (OR) 2.3, 95% confidence interval (CI) 1.6 to 3.4), emergent surgery (OR 3.3, CI 2.2 to 5.1), age (OR 1.2, CI 1.0 to 1.3), pre-operative length of stay (LOS) more than seven days (OR 1.6, CI 1.1 to 2.3), pre-operative renal insufficiency (OR 1.9, CI 1.2 to 2.9) and complex coronary disease (OR 3.1, CI 1.8 to 5.3). CONCLUSIONS: These data demonstrate an association between delirium and post-operative sepsis in the CABG population. Delirium emerged as an independent predictor of sepsis, along with traditional risk factors including age, pre-operative renal failure and peripheral vascular disease. Given the advancing age and increasing rates of delirium in the CABG population, the prevention and management of delirium need to be addressed.

The impact of sequential grafting on clinical outcomes following coronary artery bypass grafting.

OBJECTIVES: Sequential anastomoses in coronary artery bypass grafting (CABG) offer theoretical advantages including increased graft flow and more complete revascularisation. However, published studies concerning the safety and efficacy of this technique are not definitive. The objective of this study was to assess the effect of sequential anastomoses on outcomes following CABG. METHODS: Perioperative data were prospectively collected on all patients with triple-vessel disease who underwent first-time, isolated, on-pump CABG between 1995 and 2005 at a single centre. Patients with a left internal mammary artery graft to the anterior wall and saphenous vein grafts to the lateral and posterior walls were included. RESULTS: Compared to patients without sequential anastomoses (n=1108), patients with sequential anastomoses (n=1246) were more likely to have an ejection fraction (EF)<40% (14.9% vs 10.8%, p=0.004), a recent myocardial infarction (19.3% vs 14.3%, p=0.001) and an urgent/emergent operative status (19.6% vs 14.4%, p=0.0008). Median follow-up was 78 months. After adjusting for clinical covariates, sequential grafting was not an independent predictor of in-hospital adverse events (odds ratio (OR) 1.15, 95% confidence interval (CI) 0.88-1.50, p=0.31) or long-term mortality and/or readmission to hospital (hazard ratio (HR) 0.98, 95% CI 0.86-1.12, p=0.74). Sequential grafting was an independent predictor of receiving greater than three distal anastomoses (OR 9.26, 95% CI; 6.27-13.67, p<0.0001). CONCLUSIONS: Patients undergoing sequential grafting presented with greater acuity and worse systolic function. After adjusting for baseline differences, sequential grafting was not found to be an independent predictor of adverse events. These results support the safety of sequential anastomoses in patients undergoing CABG.

Long-term results of heart operations performed by surgeons-in-training.

BACKGROUND: We investigated the association between trainees performing supervised operations and late outcomes of patients undergoing cardiac surgery. METHODS AND RESULTS: Data were prospectively collected on patients who underwent coronary artery bypass graft surgery, aortic valve replacement, or a combination of these between 1998 and 2005 at the Maritime Heart Center, Halifax, Canada. In-hospital mortality and a composite outcome of in-hospital mortality, stroke, bleeding, intra-aortic balloon pump insertion, renal failure, and sternal infection was compared between teaching (n=1054) and nonteaching cases (n=5877). Late survival and cardiovascular hospital readmissions were also examined. To adjust for baseline risk disparities, we used logistic regression for dichotomous in-hospital outcomes and Cox proportional hazards regression for survival data. Resident cases were significantly more likely to have high-risk features such as depressed ventricular function, redo operation, and urgent or emergent procedure. Resident as primary operator was not independently associated with in-hospital mortality (OR, 1.09; 95% CI, 0.75 to 1.58; P=0.66) or with the composite outcome (OR, 1.01; 95%, CI 0.82 to 1.26; P=0.90). The Kaplan-Meier event-free survival of the 2 groups was equivalent at 1, 3, and 5 years (log-rank P=0.06). By Cox regression, resident cases were not associated with late death or cardiovascular rehospitalization (hazard ratio, 1.05; 95% CI, 0.94 to 1.17; P=0.42). CONCLUSIONS: Cases performed by senior-level cardiac surgery residents were more likely to have greater acuity and complexity than staff surgeon-performed cases. However, clinical outcomes were similar in the short- and long-term. Allowing residents to perform cardiac surgery is not associated with adverse patient outcomes.

Mitral insufficiency and morbidity and mortality in left ventricular dysfunction.

BACKGROUND: Mitral insufficiency is known to occur in a substantial proportion of patients with heart failure. Its relationship with morbidity and mortality is poorly described. METHODS: The mortality and hospitalization for heart failure were retrospectively examined in patients who underwent baseline echocardiography in the Studies Of Left Ventricular Dysfunction (SOLVD) treatment and prevention trials. The presence and grade of mitral insufficiency was assessed, and patients with and without mitral insufficiency were compared. RESULTS: Patients with left ventricular dysfunction and mitral insufficiency had greater than twofold increased risk of death or admission for heart failure over two years (RR 2.38, 95% CI 1.43 to 3.97). This excess risk persisted after adjustment for the severity of heart failure, etiology and differences in treatment (RR 1.82, 95% CI 1.04 to 3.17; P=0.04). The presence of moderate mitral insufficiency versus no insufficiency was associated with even greater independent risk (RR 2.20, 95% CI 1.01 to 4.80; P=0.05). Results were consistent with binary and ordinal analysis of mitral insufficiency. CONCLUSION: The presence of mitral insufficiency in patients with left ventricular dysfunction is independently associated with adverse outcomes, including death and hospitalization for heart failure. This has potentially important clinical implications for the assessment and management of patients with heart failure.

Total arterial revascularization is safe: multicenter ten-year analysis of 71,470 coronary procedures.

BACKGROUND: The purpose of this study was to assess the use of arterial revascularization and to compare the in-hospital mortality with other CABG grafting strategies. METHODS: A total of 71,470 CABG patients (1992-2001) in 27 centers in the United Kingdom were studied. The proportion of patients with arterial revascularization was compared. In-hospital mortality was compared for various grafting strategies: all-arterial (n = 5,401), all non-all-arterial patients (n = 66,069), one artery any number of veins (n = 49,801). The groups were compared for in-hospital mortality using multivariate logistic regression to assess the independent effect of the grafting strategies on mortality; logistic EuroSCORE-predicted mortality was compared to actual mortality, and all arterial and one artery and veins patients were compared with propensity score analysis. RESULTS: There was a significant increase in the proportion of all-arterial patients over time (3.2% to 11.7%, p < 0.001) with evidence of variability across centers. Crude mortality for all-arterial patients was 2% vs 3% for all non-all-arterial patients (p < 0.001). In multivariate analysis, all-arterial was associated with a slight but insignificant increase in in-hospital mortality (odds ratio [OR] 1.13; [95% confidence interval {CI} 0.86-1.48], p = 0.36). There was a trend toward higher mortality in the all-arterial group when compared with the one artery and veins group (OR 1.19 [95% CI 0.91-1.56], p = 0.10). The one artery and veins group was the only group where actual mortality was significantly lower than predicted by EuroSCORE (p < 0.001). In propensity analysis the mortality was 1.51% for one artery and veins and 1.74% of all-arterial patients (p = 0.56). CONCLUSIONS: The use of arterial grafting has increased over time, varies by center, and appears to be safe in terms of in-hospital mortality.

The preoperative intraaortic balloon pump in coronary bypass surgery: a lack of evidence of effectiveness.

BACKGROUND: There is limited evidence demonstrating the effectiveness of preoperative intraaortic balloon pump (IABP) use in isolated coronary artery bypass graft (CABG) surgery. A single-center randomized trial demonstrated its benefit. We undertook a multicenter observational study to verify this finding. METHODS: In 29,950 consecutive patients undergoing isolated CABG between 1995 and 2000 at 10 centers, we compared patients with and without a preoperative IABP. We also compared the effect of preoperative IABP use within 7 high-risk clinical subgroups. To validate the previous randomized trial, patients with any 2 of the following were also analyzed: left main > 70%, ejection fraction < 40%, redo CABG, or preoperative intravenous nitroglycerin. RESULTS: Preoperative IABPs were used in 1896 patients (6.3%). These patients had more comorbid conditions and a higher crude mortality than those who did not have preoperative IABPs (9.5% vs 2.3%, P < .0001). Preoperative IABP patients were caliper matched to non-preoperative IABP patients using a propensity score. Excess mortality associated with preoperative IABP persisted (9.2% vs 5.8%, P = .0004). In 7 high-risk subgroups, mortality was significantly higher with preoperative IABP. We used propensity caliper matching to compare preoperative IABP with non-preoperative IABP patients who met trial criteria (n = 4332). Preoperative IABP was associated with higher mortality (11.0% vs 6.5%, P = .0009). Removing emergency patients did not alter results. CONCLUSIONS: Use of preoperative IABPs was consistently associated with higher mortality. Despite detailed statistical analysis, we were unable to show benefit from preoperative IABP use or confirm the results of a single-center trial that demonstrated its benefit. Assessment of preoperative IABP efficacy will require a randomized trial.

The association between prior percutaneous coronary intervention and short-term outcomes after coronary artery bypass grafting.

BACKGROUND: Increasingly, patients are being referred for coronary artery bypass grafting (CABG) for management of symptoms after prior percutaneous coronary intervention (PCI). In this study, we assessed the impact of prior PCI on inhospital mortality after CABG. METHODS: Perioperative data were collected on patients who underwent first-time CABG at 2 surgical centers. Patients who underwent PCI and CABG during the same admission were excluded. Patients with prior PCI were compared with patients with no prior PCI, and the risk-adjusted impact of prior PCI on inhospital mortality after CABG was determined using both multivariate techniques and propensity score matching techniques. RESULTS: Six thousand thirty-two patients met inclusion criteria. Patients with prior PCI were less likely to be between the ages of 70 and 80 (P < .0001), to have an ejection fraction <0.40 (P < .0001), and to have 3-vessel/left main disease (P < .0001). They were, however, more likely to have Canadian Cardiovascular Society class IV symptoms (P < .0001) and to have an urgent status (P = .02). Rates of inhospital mortality after CABG were higher in patients with prior PCI (3.6% vs 2.3%, P = .02). Using multivariate techniques, prior PCI emerged as an independent predictor of postoperative inhospital mortality (odds ratio 1.93, P = .003). When patients with prior PCI were matched to patients with no prior PCI using propensity scores, inhospital mortality remained higher among patients with prior PCI (3.6% vs 1.7%, P = .01). CONCLUSION: Patients with prior PCI presented for CABG with less comorbidity and diminished coronary disease; yet, they had more advanced symptoms and greater urgency. After adjusting for these differences, prior PCI emerged as an independent predictor of inhospital mortality after CABG.

Pulmonary artery to distal bypass for surgery on the descending thoracic aorta.

A variety of extracorporeal techniques have been described in surgery of the descending thoracic and thoracoabdominal aorta. We describe an operative approach involving the cannulation of the pulmonary artery for venous drainage in 12 patients undergoing descending thoracic aortic surgery. In-hospital mortality was 17%; there were no in-hospital deaths for elective cases. There were no cases of post-operative paraplegia. Cannulation of the pulmonary artery is a safe and technically simple means of providing venous drainage during cardiopulmonary bypass in aortic surgery. This is an effective approach to distal perfusion in aortic surgery that is associated with excellent flows and avoids cannulating the left side of the heart.

Training residents in mitral valve surgery.

BACKGROUND: The safety of training residents in complex procedures has not been elucidated. In particular, the impact of resident-performed mitral valve surgery on patient outcomes is unknown. METHODS: All mitral valve procedures performed by residents between 1998 and 2003 were compared with those performed by staff surgeons. Operative mortality and a composite morbidity (reoperation for bleeding, myocardial infarction, infection, stroke, or ventilation > 24 hours) were compared using multivariate analysis. Individual outcomes were compared with the use of propensity scores. RESULTS: There were 1020 cardiac surgeries performed by residents, including 165 mitral valve procedures (86 replacements, 79 repairs). In the same period, the staff surgeons performed 261 mitral procedures. Crude operative mortality for isolated mitral procedures was 5.4% and 4.7% (resident and staff, respectively, p = 1.00). Mitral valve repair including combined procedures had an operative mortality of 3.8% and 4.3% (resident and staff, respectively, p = 1.00). The composite morbidity outcome was 29.7% and 35.3% for resident and staff-performed cases, respectively (p = 0.24). In multivariate analysis, resident was not associated with the adverse outcomes examined (OR 0.80, 95% CI, 0.47, 1.37). The incidence of major adverse outcomes for propensity score-matched mitral valve cases, including combined procedures, were similar between residents and staff, respectively: mortality, 7.4% versus 8.7% (p = 0.67), stroke, 4.0% versus 6.7% (p = 0.30), and reoperation for bleeding, 4.7% versus 9.4% (p = 0.11). CONCLUSIONS: There were no significant differences in morbidity and mortality in patients undergoing mitral valve surgery between resident and staff surgeons. It is possible to train residents to perform complex cardiac cases without adversely affecting outcomes.

A multicenter comparison of intraaortic balloon pump utilization in isolated coronary artery bypass graft surgery.

BACKGROUND: Single-center studies suggest substantial variation in intraaortic balloon pump (IABP) utilization. Our purpose is to examine IABP utilization over time and across medical centers. METHODS: This was a prospective cohort of 29,961 consecutive patients undergoing isolated coronary artery bypass graft surgery, between 1995 and 2000, at 10 centers (eight in northern New England and two in Canada). RESULTS: A total of 2,678 (8.9%) patients received an IABP. The rate of preoperative IABP insertion was 6.3%, and that of intra- or postoperative insertion was 2.6%. During the 6 years, IABP use increased from 7.0% to 10.3% (p(trend) <0.001). Preoperative IABP insertion increased from 5.4% to 7.8% (p(trend) < 0.001). There was no significant increase in intra-/postoperative IABP insertion 1.7% to 3.4% (p(trend) = 0.34). Adjustment for changes in patient and disease characteristics did not substantially alter these results. The rate of IABP use varied substantially by center, from 5.9% to 16.4% (p < 0.001). Adjustment for patient and disease characteristics resulted in variation from 4.8% to 12.8% across the 10 centers (p < 0.001). The adjusted rates of preoperative IABP insertion varied from 3.6% to 13.7% (p < 0.001), and the rates of intra-/postoperative IABP insertion ranged from 1.0% to 5.2% (p < 0.001). There was no significant correlation between the rates of preoperative and intra-/postoperative IABP use (r(s) = 0.085, p = 0.815). CONCLUSIONS: During the 6 years, there was a 47% increase in the rate of IABP utilization. Even after adjustment, there was almost threefold variation in IABP use across centers. This variation likely reflects lack of consensus on the appropriate use of the IABP in CABG patients.

Infectious endocarditis of a Chiari network.

We present the case of a 62-year-old man with infectious endocarditis in a Chiari network. Chiari networks are present in 1.5% to 3% of the population. Although Chiari networks are usually clinically insignificant, they are associated with a number of conditions, including patent foramen ovale, thromboembolism, atrial aneurysm, and cardiac arrhythmias. Although there are rare reports of patients with a Chiari network who had endocarditis develop, this is the first report of a patient who had endocarditis develop solely within a Chiari network.

Human leukocyte antigen-DR and ABO mismatch are associated with accelerated homograft valve failure in children: implications for therapeutic interventions.

OBJECTIVE: This study examines the incidence and factors associated with the failure of homograft valves and identifies those factors that are modifiable. METHODS: From 1990 to 2001, 96 homograft valves were implanted in the right ventricular outflow tract of 83 children (mean age 5.1 +/- 5.6 years). Clinical and blinded serial echocardiographic follow-up was performed on all 90 valves in the 77 survivors. RESULTS: Eighteen homograft valves were replaced as the result of pulmonary insufficiency (3), stenosis (9), or both (6). Freedom from reoperation was 71% at 9 years (95% confidence interval, 58%-84%). Forty-eight valves developed progressive pulmonary insufficiency of at least 2 grades, 26 valves developed transvalvular gradients of 50 mm Hg or greater, and 14 of these valves were also insufficient. The freedom from echocardiographic failure (progressive pulmonary insufficiency >or=2 grades or >or=50 mm Hg gradient) was only 27% at 5 years (95% confidence interval, 17%-37%). In a multivariate analysis (Cox regression), use of an aortic homograft (P =.001) and short antibiotic preservation time (P =.04) were associated with reoperation. Younger age (P =.01), ABO mismatch (P =.04), and diagnosis (P =.005) were associated with echocardiographic failure. In the subanalysis of patients with human leukocyte antigen typing, age (P =.002), aortic homograft (P =.04), and human leukocyte antigen-DR mismatch (P =.03) were associated with echocardiographic valve failure. CONCLUSION: Many homografts rapidly become insufficient and require replacement. In our analysis of both reoperation and echocardiographic failure, several immunologic factors are consistently associated with homograft failure. Matching for human leukocyte antigen-DR, blood group, and avoiding short preservation times (thus minimizing antigenicity) offers the potential to extend the life of these valves.