Lois U. Nwakanma

Aortic Root Replacement in 372 Marfan Patients: Evolution of Operative Repair Over 30 Years

BACKGROUND We reviewed the evolution of practice and late results of aortic root replacement (ARR) in Marfan syndrome patients at our institution. METHODS A retrospective clinical review of Marfan patients undergoing ARR at our institution was performed. Follow-up data were obtained from hospital and office records and from telephone contact with patients or their physicians. RESULTS Between September 1976 and September 2006, 372 Marfan syndrome patients underwent ARR: 269 had a Bentall composite graft, 85 had valve-sparing ARR, 16 had ARR with homografts, and 2 had ARR with porcine xenografts. In the first 24 years of the study, 85% received a Bentall graft; during the last 8 years, 61% had a valve-sparing procedure. There was no operative or hospital mortality among the 327 patients who underwent elective repair; there were 2 deaths among the 45 patients (4.4%) who underwent emergent or urgent operative repair. There were 74 late deaths (70 Bentalls, 2 homograft, and 2 valve-sparing ARRs). The most frequent causes of late death were dissection or rupture of the residual aorta (10 of 74) and arrhythmia (9 of 74). Of the 85 patients who had a valve-sparing procedure, 40 had a David II remodeling operation; there was 1 late death in this group, and 5 patients required late aortic valve replacement for aortic insufficiency. A David I reimplantation procedure using the De Paulis Valsalva graft has been used exclusively since May 2002. All 44 patients in this last group have 0 to 1+ aortic insufficiency. CONCLUSIONS Prophylactic surgical replacement of the ascending aorta in patients with Marfan syndrome has low operative risk and can prevent aortic catastrophe in most patients. Valve-sparing procedures, particularly using the reimplantation technique with the Valsalva graft, show promise but have not yet proven as durable as the Bentall.

Aortic Root Operations for Marfan Syndrome: A Comparison of the Bentall and Valve-Sparing Procedures

BACKGROUND We compared results of the Bentall procedure with valve-sparing aortic root replacement (VSRR) for aortic root aneurysm in Marfan syndrome. METHODS Marfan syndrome patients who had the Bentall procedure or VSRR at our institution between April 1997 and September 2006 were identified. Follow-up information was obtained from hospital charts and contact with patients or their physicians. Kaplan-Meier survival and propensity score analyses were performed. RESULTS One hundred forty Marfan syndrome patients had either the Bentall procedure (n = 56) or VSRR (n = 84; 40 remodeling and 44 reimplantation). Bentall patients were older than VSRR patients (38 versus 29 years; p = 0.0001) and had more aortic dissections (16% versus 1%; p = 0.0012); more urgent/emergent surgery (20% versus 2%; p = 0.0008); larger preoperative sinus diameter (5.7 versus 5.1 cm; p = 0.0004); and more preoperative 3+/4+ aortic insufficiency (59% versus 10%; p < 0.0001). There were no operative deaths. Postoperatively, 9% Bentall patients (5 of 56) and 1% of VSRR patients (1 of 84) suffered thromboembolic events (p = 0.03). Two percent (1 of 56) of Bentall patients required reoperation on the aortic root versus 6% of VSRR patients (5 of 84; p = 0.40). Eight-year freedom from aortic valve replacement was 90% for VSRR patients. Eight-year survival was 90% for Bentall and 100% for VSRR patients (p = 0.01). Propensity-adjusted regression showed that the Bentall procedure did not predict mortality (p = 1.00) and did not protect from reoperation (odds ratio = 0.28; 95% confidence interval: 0.01 to 4.33; p = 0.36). CONCLUSIONS The Bentall procedure and VSRR have similar operative results in Marfan syndrome. The procedures are distinguished by higher rates of thromboembolism among Bentall patients and higher rates of reoperation among VSRR patients. Lower late survival among Bentall patients probably reflects the preferential use of the Bentall procedure for higher risk patients.

Impact of Donor-to-Recipient Weight Ratio on Survival After Heart Transplantation : Analysis of the United Network for Organ Sharing Database

Background— Generally accepted donor criteria for heart transplantation limit allografts from donors within approximately 20% to 30% of the recipient’s weight. We analyzed the impact of donor-to-recipient weight ratio on survival after heart transplantation. Methods and Results— Adult heart transplant recipients reported to the United Network for Organ Sharing from 1999 to 2007 were divided into 3 groups based on donor-to-recipient weight ratio: <0.8, 0.8 to 1.2, and >1.2. Kaplan–Meier methodology was used to estimate survival. Propensity-adjusted Cox regression modeling was used to analyze predictors of mortality. A total of 15 284 heart transplant recipients were analyzed; 2078 had weight ratio of <0.8, 9684 had 0.8 to 1.2, and 3522 had >1.2. Kaplan–Meier survival was not statistically different between groups at 5 years (P=0.26). Among patients with weight ratio <0.8, 5-year survival was lower for recipients with high pulmonary vascular resistance (>4 Woods units; P=0.02). Among recipients with high pulmonary vascular resistance, 5-year survival was similar for those with weight ratio 0.8 to 1.2 and >1.2 (P=0.44). Furthermore, male recipients with elevated pulmonary vascular resistance who received hearts from female donors had a significantly worse survival than males who received hearts from male donors (P=0.01). Propensity-adjusted multivariable analysis demonstrated that weight ratio <0.8 did not predict mortality (hazard ratio, 1.09; 95% CI, 0.94 to 1.27; P=0.21). Five-year survival after propensity matching was not statistically different between those with weight ratio <0.8 versus ≥0.8 (P=0.37). Conclusions— Weight ratio did not predict mortality after heart transplantation. However, recipients with elevated pulmonary vascular resistance who received undersized hearts had poor survival. Furthermore, in the setting of high pulmonary vascular resistance, male recipients who received hearts from female donors had worse survival than those who received hearts from male donors. Extending donor criteria to include undersized hearts in select recipients should be considered.

EuroSCORE Predicts Short- and Mid-Term Mortality in Combined Aortic Valve Replacement and Coronary Artery Bypass Patients

Abstract  Background and Aim of the Study: European system for cardiac operative risk evaluation (EuroSCORE) has been studied for its effectiveness in predicting operative mortality, and more recently, long‐term mortality in a wide variety of cardiac surgical procedures. Combined coronary artery bypass and aortic valve replacement (AVR‐CABG) carries increased perioperative risk, and tends to have higher‐risk patients. Performance of the EuroSCORE system in patients undergoing concomitant AVR‐CABG has not been well established. Thus, we aimed to analyze the accuracy of both additive and logistic EuroSCOREs in predicting operative and mid‐term mortality. Methods: We retrospectively reviewed and calculated EuroSCOREs for all patients who underwent AVR‐CABG between January 2000 and December 2004. Patients who had previous cardiac surgery and those undergoing any concomitant procedures were excluded. Areas under the receiver operator curves (ROC) were determined to assess EuroSCOREs accuracy in predicting operative mortality. Kaplan‐Meier analysis and Cox regression were used to determine mid‐term survival, freedom from repeat revascularization, and predictors of these outcomes. Results: There were 233 patients who met study criteria. Mean follow‐up period was 2.2 ± 1.7 years with one patient lost to follow‐up. Mean additive and logistic EuroSCOREs were 8.77 and 16.1, respectively, with an observed mortality of 9.44%. The area under the ROC curves for additive EuroSCORE was 0.76 and for logistic EuroSCORE was 0.75. Regression analysis revealed additive EuroSCORE, but not logistic EuroSCORE, to be predictive of mid‐term mortality. Conclusions: Both additive and logistic EuroSCOREs were accurate in predicting operative morality. Only additive EuroSCORE was predictive of mid‐term mortality in AVR‐CABG patients. EuroSCORE remains a good and well‐validated risk stratification model applicable to patients who undergo concomitant AVR‐CABG.

Pretransplant panel reactive antibodies in human lung transplantation: an analysis of over 10,000 patients.

BACKGROUND The role of panel reactive antibody (PRA) in lung transplant recipients has not been clearly defined in a large population. We sought to determine how panel reactive antibody level affects survival in lung transplant recipients. METHODS The United Network for Organ Sharing (UNOS) Standard Transplant Analysis and Research files from 1987 through 2005 were analyzed. Demographic data, pretransplant PRA, relevant clinical indicators, and survival were examined. RESULTS Of the 12,751 first lung transplant recipients during this period, pretransplant PRA levels were reported for 10,237 patients. Panel reactive antibody was more than 0% in 1748 patients; of these, PRA was 1% to 10% in 1259 (72%), 11% to 25% in 249 (14%), and more than 25% in 240 (14%). Using the Kaplan-Meier method, survival decreased with increasing PRA and was significant when PRA exceeded 25% compared with the rest of the cohort. On multivariable analysis, PRA was associated with increased 30-day (hazard ratio, 2.6) and overall mortality (hazard ratio, 1.3). Importantly, this effect was not seen when a cohort from 1998 through 2005 was analyzed. CONCLUSIONS The UNOS database has provided the largest series of lung transplant patients stratified by PRA. Our analysis demonstrates that PRA level exceeding 25% is a predictor of death. However, newer laboratory and management techniques may attenuate this effect with better outcomes in the modern era.

Alpha II-spectrin Breakdown Products Serve as Novel Markers of Brain Injury Severity in a Canine Model of Hypothermic Circulatory Arrest

BACKGROUND The development of specific biomarkers to aid in the diagnosis and prognosis of neuronal injury is of paramount importance in cardiac surgery. Alpha II-spectrin is a structural protein abundant in neurons of the central nervous system and cleaved into signature fragments by proteases involved in necrotic and apoptotic cell death. We measured cerebrospinal fluid alpha II-spectrin breakdown products (alphaII-SBDPs) in a canine model of hypothermic circulatory arrest (HCA) and cardiopulmonary bypass. METHODS Canine subjects were exposed to either 1 hour of HCA (n = 8; mean lowest tympanic temperature 18.0 +/- 1.2 degrees C) or standard cardiopulmonary bypass (n = 7). Cerebrospinal fluid samples were collected before treatment and 8 and 24 hours after treatment. Using polyacrylamide gel electrophoresis and immunoblotting, SBDPs were isolated and compared between groups using computer-assisted densitometric scanning. Necrotic versus apoptotic cell death was indexed by measuring calpain and caspase-3 cleaved alphaII-SBDPs (SBDP 145+150 and SBDP 120, respectively). RESULTS Animals undergoing HCA demonstrated mild patterns of histologic cellular injury and clinically detectable neurologic dysfunction. Calpain-produced alphaII-SBDPs (150 kDa+145 kDa bands-necrosis) 8 hours after HCA were significantly increased (p = 0.02) as compared with levels before HCA, and remained elevated at 24 hours after HCA. In contrast, caspase-3 alphaII-SBDP (120 kDa band-apoptosis) was not significantly increased. Animals receiving cardiopulmonary bypass did not demonstrate clinical or histologic evidence of injury, with no increases in necrotic or apoptotic cellular markers. CONCLUSIONS We report the use of alphaII-SBDPs as markers of neurologic injury after cardiac surgery. Our analysis demonstrates that calpain- and caspase-produced alphaII-SBDPs may be an important and novel marker of neurologic injury after HCA.

Coronary artery bypass grafting with or without surgical ventricular restoration: a comparison.

BACKGROUND Coronary artery bypass grafting (CABG) is an effective treatment for ischemic cardiomyopathy. However, patients with ventricular enlargement are known to have inferior outcomes. We assessed whether surgical ventricular restoration (SVR) with CABG (SVR + CABG) leads to improved outcomes versus CABG alone for patients with ischemic cardiomyopathy and ventricular enlargement. METHODS We conducted a case-control study comparing patients with ischemic cardiomyopathy and ejection fraction less than 0.35 who underwent SVR + CABG versus CABG alone from June 2002 to December 2005. Patients who underwent SVR + CABG were compared with control patients who met criteria for SVR + CABG by ventriculogram or echocardiogram but received CABG alone. End points included survival, rehospitalization for heart failure, and New York Heart Association class. RESULTS During the study period 120 patients underwent SVR + CABG (n = 62) versus CABG alone (n = 58). Patients in the SVR + CABG group were younger (60 versus 64 years; p = 0.04) and more likely to be New York Heart Association class III or IV preoperatively (98% versus 86%; p = 0.01). Operative mortality was similar between groups (6.4% versus 5.2%; p = 1.00). Ejection fraction was similar preoperatively (0.22 versus 0.24; p = 0.31) and postoperatively (0.34 versus 00.32; p = 0.40). The SVR + CABG patients experienced fewer rehospitalizations for heart failure (24% [13 of 54] versus 55% [24 of 44]; p = 0.006) but had similar 4-year survival (p = 0.60). At follow-up, 80% (50 of 62) of SVR + CABG versus 57% (27 of 47) of CABG alone patients improved to New York Heart Association class I or II (p = 0.01). CONCLUSIONS Patients with ischemic cardiomyopathy and ventricular enlargement experience similar early survival after SVR + CABG or CABG alone. However, SVR + CABG resulted in fewer rehospitalizations and better improvements in New York Heart Association class. Surgical ventricular restoration with CABG should be offered to eligible patients with ischemic cardiomyopathy and ventricular enlargement.

The Impact of Surgical Ventricular Restoration on Mitral Valve Regurgitation

BACKGROUND Surgical management of functional mitral regurgitation (MR) in ischemic cardiomyopathy is controversial. Surgical ventricular restoration (SVR) decreases left ventricular volume and may improve MR severity. We assessed the impact of SVR on the degree of MR. METHODS We retrospectively reviewed patients with ejection fractions (EF) < 0.35 who underwent SVR with coronary artery bypass grafting (SVR+CABG) over a 3-year period. Patients with concomitant mitral valve procedures were excluded. Patients with EF < 0.35 who had CABG alone during the same time period served as control. Mitral regurgitation was graded 0 to 4+ by echocardiogram and ventriculogram. Outcomes included survival, MR grade, and cardiac function. RESULTS Thirty-nine patients received SVR+CABG: 3% (1 of 39) had 4+, 10% (4 of 39) had 3+, 51% (20 of 39) had 2+, and 36% (14 of 39) had 0 to 1+ MR. Thirty-five patients with a similar MR distribution underwent CABG alone. Operative mortality was 2.6% for SVR+CABG and 5.7% for CABG patients (p = 0.62). At follow-up, MR grade decreased by 57% (2.24 +/- 0.5 to 1.24 +/- 0.9, p < 0.001) for the SVR+CABG group compared to 12% (2.25 +/- 0.5 to 2.00 +/- 0.9, p = 0.27) for the CABG alone group. SVR+CABG patients had significantly less MR than CABG patients at follow-up (1.24 +/- 0.9 vs 2.00 +/- 0.9, p = 0.007), with 15 patients improving to 0 to 1+ MR postoperatively versus 6 patients in the CABG cohort (p = 0.02). Improvement in postoperative EF was significantly greater after SVR+CABG (0.13% vs 7%, p = 0.04). Three-year survival was 85% for SVR+CABG and 72% for CABG patients (p = 0.39). CONCLUSIONS SVR+CABG demonstrated greater reduction in MR severity at follow-up than CABG alone. Decreased left ventricular volumes and improved papillary muscle orientation likely contribute to decreased MR after SVR.

Idiopathic Pulmonary Artery Aneurysm Treated With Surgical Correction and Concomitant Coronary Artery Bypass Grafting

Idiopathic pulmonary artery aneurysm is a rare clinical entity, and therefore the natural course and clinical management are not well established. We present the case of an elderly woman with a symptomatic idiopathic pulmonary artery aneurysm who underwent surgical repair along with simultaneous coronary artery bypass grafting. With long-term follow-up presented in this report, we describe the safety and durability of surgical repair.

Surgical Ventricular Restoration Versus Cardiac Transplantation: A Comparison of Cost, Outcomes, and Survival

BACKGROUND Cardiac transplantation is the accepted standard treatment for end-stage heart disease but is donor limited. Surgical ventricular remodeling is an established treatment for patients with ischemic cardiomyopathy. We sought to compare charges, outcomes, and survival in patients undergoing surgical ventricular restoration (SVR) versus cardiac transplantation (CTx). METHODS AND RESULTS We retrospectively analyzed hospital charges, length of stay (LOS), and survival for 69 SVR and 53 CTx patients at our institution between January 2002 and June 2005. We also compared New York Heart Association (NYHA) status and Kaplan-Meier survival of our SVR patients with CTx patients with ischemic cardiomyopathy from the International Society of Heart & Lung Transplantation (ISHLT) registry. Median total LOS (12 days vs. 17 days, P = .01) and median postoperative LOS (10 days vs. 15 days, P = .02) were shorter for SVR patients than our CTx patients. Median total hospital charges (