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YingXing Wu

Publications and source records attributed to YingXing Wu.

15 recordsLinked to original sources
PubMed2005

Randomized trial of endoscopic versus open vein harvest for coronary artery bypass grafting: six-month patency rates.

OBJECTIVE: We sought to compare the 6-month angiographic patency rates of greater saphenous veins removed during coronary artery bypass grafting with the endoscopic vein harvest or open vein harvest techniques. METHODS: Two hundred patients undergoing nonemergency on-pump coronary artery bypass grafting were prospectively randomized to either endoscopic vein harvest or open vein harvest. Follow-up angiography of all vein grafts was scheduled at 6 months. Graft patency and disease grades were assigned independently by 2 interventional cardiologists. Leg wound healing was evaluated at discharge, 1 month, and 6 months for evidence of complications. RESULTS: There were 3 conversions from endoscopic vein harvest to open vein harvest because of vein factors. Leg wound complications were significantly lower in the endoscopic vein harvest group (7.4% vs 19.4%, P = .014). On multivariable analysis, endoscopic vein harvest emerged as the only factor affecting wound complications (odds ratio, 0.33). Three deaths (2 perioperative and 1 late) occurred in the endoscopic vein harvest group that were unrelated to vein graft closure. Twenty-four and 29 patients in the endoscopic vein harvest and open vein harvest cohorts, respectively, refused the follow-up 6-month angiography. Therefore a total of 144 angiograms (73 endoscopic vein harvests and 71 open vein harvests) and 336 vein grafts (166 endoscopic vein harvests and 170 open vein harvests) were available for analysis. The overall occlusion rates at 6 months were 21.7% for endoscopic vein harvest and 17.6% for open vein harvest. Additionally, there was evidence of significant disease (>50% stenosis) in 10.2% and 12.4% of endoscopic vein harvest and open vein harvest grafts, respectively. By means of ordinal hierarchic logistic regression, endoscopic vein harvest was not found to be a risk factor for vein graft occlusion or disease (odds ratio, 1.15). Significant predictors were congestive heart failure (odds ratio, 2.87), graft to the diagonal artery territory (odds ratio, 1.76), larger vein conduit size (odds ratio, 1.32), and graft flow (odds ratio, 0.90). CONCLUSION: Endoscopic vein harvest reduces leg wound complications compared with open vein harvest without compromising the 6-month patency rate. The overall patency rate depends on target and vein-related variables and patient characteristics rather than the method of vein harvesting.

Aged↗
PubMed2004

Durability of pericardial versus porcine aortic valves.

OBJECTIVES: This study compares the long-term performance of the Carpentier-Edwards (CE) porcine bioprosthesis and the CE pericardial bioprosthesis for aortic valve replacement (AVR). BACKGROUND: With new bioprostheses on the horizon, there is renewed interest in how the long-term durability of current pericardial bioprostheses compares with the traditional porcine bioprosthesis. METHODS: We reviewed 518 AVR with CE porcine valves from 1974 to 1996 and 1,021 AVR with CE pericardial valves from 1991 to 2002. The age distribution and clinical profiles were similar for both groups. The total (mean) follow-up was 3,322 (6.4) years for porcine and 2,556 (2.5) years for pericardial. RESULTS: Long-term mortality was similar (p = 0.29) for porcine and pericardial, with 10-year survival rates of 34 +/- 2% and 38 +/- 6%, respectively. Ten-year freedom from major adverse cardiac events was also similar for both (respectively): thromboembolism (80 +/- 2% and 87 +/- 2%; p = 0.24); endocarditis (98 +/- 1% and 99 +/- 1%; p = 0.30). However, 10-year freedom from explant was lower for porcine (90 +/- 2%) than for pericardial (97 +/- 1%, p = 0.04). Reasons for explant for porcine were structural valve deterioration (SVD) (n = 25), endocarditis (n = 4), and periprosthetic leak (n = 2). The reasons for explant for pericardial were SVD (n = 4), endocarditis (n = 4) and periprosthetic leak (n = 1). CONCLUSIONS: The current CE pericardial valve offers better midterm durability than the traditional CE porcine valve. Its freedom from SVD and reoperation makes it our current bioprosthesis of choice for AVR in appropriately selected patients.

Adult↗
PubMed2004

The risks and benefits of reoperative aortic valve replacement.

BACKGROUND: Many patients are advised to have mechanical aortic valve replacement (AVR) because their expected longevity exceeds that of tissue prostheses. This strategy may avoid the risks of reoperation but exposes patients to the risks of long-term anticoagulation therapy. Which risk is greater? METHODS: We reviewed the records of 1213 consecutive, unselected AVR patients, 60% of whom had concomitant procedures, who were treated from 1994 through 2002. Of these patients, 887 were first-time AVR patients, and 326 underwent reoperation. Of the reoperation patients, 134 had previously undergone AVR (redo). We constructed a risk model from these 1213 cases to assess the factors that predicted mortality and to examine the extent to which reoperation affected outcome. RESULTS: Multiple logistic regression analysis indicated that factors of reoperation and redo operation did not predict mortality. In fact, the mortality rate was 4.1% for all first AVR operations and 3.1% for all reoperation AVR ( P =.891). Significant predicting factors (with odds ratios) were reoperative dialysis (6.03), preoperative shock (3.68), New York Heart Association class IV (2.20), female sex (1.76), age (1.61), and cardiopulmonary bypass time (1.26). CONCLUSIONS: In this series, the risk of reoperation AVR is comparable with the published risks of long-term warfarin sodium (Coumadin) administration after mechanical AVR. Any adult who requires AVR may be well advised to consider tissue prostheses.

Aged↗
PubMed2004

Mitral valve operations through standard and smaller incisions.

OBJECTIVE: Evaluate the operative results of mitral valve repair (MVV) and mitral valve replacement (MVR) performed through standard and smaller incisions. METHODS: From January 1997 through December 2002, 821 consecutive patients underwent mitral valve operation. Of these procedures, 475 were MVV and 346 were MVR. A logistic regression model was developed to identify the risk factors for early mortality and to evaluate the effect of replacement versus repair and standard versus small incision. RESULTS: Replacement patients were older, more likely New York Heart Association (NYHA) class III or IV, more likely female, and had more frequent previous median sternotomy and stroke (all P <.05). The mitral diagnoses in the 2 groups were markedly different. Prolapse and ischemia dominated the repairs, whereas calcific and rheumatic diagnoses required replacement. There were 667 concomitant procedures performed on these patients, most commonly coronary artery bypass graft (229), aortic valve replacement (170), maze (79), and tricuspid valve (TV) repair/replacement (73). Thirty-three patients (4.0%) died in the postoperative period, 2.3% after repair and 6.4% after replacement ( P <.01). Endocarditis (4/17), calcific disease (7/73), and ischemic disease (9/121) accounted for 26% of patients and 60% of deaths. Multivariate regression analysis identified NYHA class, emergent status, concomitant TV operation, and history of renal failure, but not repair versus replacement, as independent risk factors predicting mortality. We estimated that 356 of the 821 patients (43%) were candidates for small-incision operations, the others were excluded by the need for concomitant procedure or other cause. A total of 205/356 (57%) actually underwent small-incision operations, all with central cannulation and standard techniques. From 1997-1999, 32% of eligible patients were so treated, but from 2000-2002, with increasing surgeon experience, this percentage rose significantly to 71% ( P <.01). Eligible patients who underwent small-incision operation were younger and had lower NYHA classifications, lower preoperative creatinine, and shorter length of stay (all P <.01) than those who had standard incisions. Cross-clamp time, perfusion time, and mortality rate were not significantly different. CONCLUSIONS: The mortality rate for MV operations is concentrated among a few diagnoses. In some patients surgery may be approached safely through smaller incisions without introducing new elements of operative risk.

Aged↗
PubMed2004

Sternal preservation: a better way to treat most sternal wound complications after cardiac surgery.

BACKGROUND: Postcardiotomy sternal wound complications remain challenging. The prevailing approach for deep sternal wound infection of debridement and flap coverage without osseous closure makes subsequent reoperation difficult. METHODS: An analysis of all patients undergoing cardiac surgery at a single institution between 1986 and 2001 was conducted. Prospective data collection and chart review were used to compare different treatment strategies for sternal complications. RESULTS: Of 5337 patients, 122 had sternal wound complications (2.2%) comprising 15 (0.3%) uninfected dehiscences (El Oakley class 1), 45 (0.8%) superficial infections (El Oakley class 2A), and 62 (1.1%) deep sternal wound infections (El Oakley class 2B). Thirty-two patients with deep sternal infection were treated by debridement, rewiring, and delayed primary closure. There were initial treatment failures in 6 patients (18.8%) and ultimate failures in 2 patients (6.3%), both of whom died. One of these patients had previously received external beam radiation after a radical mastectomy for breast cancer. Median length of stay was 32 days and median time to wound healing was 85 days. Twenty-five patients were managed by muscle flap coverage without sternal reclosure. There were 6 initial treatment failures (24%) but no ultimate failures or deaths (p = NS). Median length of stay was 31 days and median infection time was 161 days. CONCLUSIONS: In patients with postcardiotomy deep sternal wound infection without previous chest radiation, debridement, rewiring, and delayed skin closure is effective. It offers a shorter healing time and probably makes late cardiac reoperation safer. We propose an algorithm for the management of poststernotomy complications.

Algorithms↗
PubMed2004

The Silzone effect: how to reconcile contradictory reports?

OBJECTIVE: To attempt to reconcile reports containing contradictory findings with the St. Jude Medical Silzone heart valve. METHODS: Major leak and thromboembolism data were extracted from available Silzone valve studies. Linearized rates were used to summarize and compare the events rates among the studies. RESULTS: The Artificial Valve Endocarditis Reduction Trial (AVERT) study reported significant higher rate of major leak and the Cardiff Embolic Risk Factor Study (CERFS) reported significant higher rate of thromboembolism with Silzone compared to non-Silzone valves. But, current updates of these studies show a diminution of these differences. Three other comparative studies reported no difference between Silzone and non-Silzone valves, and three single arm studies reported acceptable results with Silzone valves. CONCLUSION: The contradictory findings could be partly due to clinical and technical reasons. No new events have been reported since the original AVERT (major leak) and CERFS (mitral thromboembolism) publications.

Endocarditis↗
PubMed2004

Coronary artery bypass grafting: are risk models developed from on-pump surgery valid for off-pump surgery?

OBJECTIVE: This study was undertaken to test whether risk models developed from on-pump coronary artery bypass grafting are valid for assessing the risk for off-pump coronary artery bypass grafting. METHODS: From January 1997 through June 2002, a total of 12,845 patients underwent isolated coronary artery bypass grafting procedures in Providence Health System hospitals. Of these, 1782 operations (14%) were performed without cardiopulmonary bypass. An operative mortality risk model was derived from on-pump data with logistic regression. This model and two other external risk models developed from on-pump data were then applied to patients undergoing off-pump coronary artery bypass grafting to test the model adequacy. RESULTS: Good model discrimination and calibration were obtained from all three models. CONCLUSION: Operative mortality risk models developed from on-pump coronary artery bypass grafting can be used to assess the risk for off-pump coronary artery bypass grafting.

Aged↗
PubMed2004

Mechanical heart valves: are two leaflets better than one?

OBJECTIVE: We sought to compare the long-term clinical outcomes of patients who underwent isolated aortic valve replacement with single-disc and bileaflet mechanical heart valves. METHODS: From May 1975 through October 2001, 590 single-disc valves (7 models) were used for isolated valve replacement, and from November 1980 through July 2002, 1283 bileaflet valves (10 models) were used for isolated valve replacement. Detailed follow-up was performed to a maximum of 27.4 and 21.9 years with a total of 6872 and 5811 patient-years for single-disc valves and bileaflet valves, respectively. Survival and valve-related events were analyzed. RESULTS: Single-disc valves were mainly implanted from 1975 through 1995, whereas bileaflet valves were mainly implanted from 1987 through 2002; thus the years of concurrent use were 1987 through 1995. The bileaflet valve had a significantly lower explantation rate, whereas the single-disc valve had a significantly lower thromboembolism rate. No significant differences were detected in early mortality, long-term survival, and other valve-related complications. When limiting the comparison to the concurrent period of 1987 through 1995, no significant difference was detected in survival or in any valve-related complication. CONCLUSION: Single-disc and bileaflet valves provide similar clinical performance. The predominant use of bileaflet valves is not based on clinical outcomes.

Adult↗
PubMed2004

Forty-year survival with the Starr-Edwards heart valve prosthesis.

BACKGROUND AND AIM OF THE STUDY: The study aim was to update an analysis of the long-term survival of heart valve replacement using the Starr-Edwards prosthesis. METHODS: Cases of isolated aortic (AVR, n = 2,247) and mitral (MVR, n = 1,406) valve replacement with Starr-Edwards prostheses implanted between 1960 and 1997, with follow up to 2003, were reviewed. Introduced in 1965, the Models A1200/1260, M6120 are still in use (Current), while other models have been discontinued (Discontinued). For AVR, 938 valves were Discontinued, with a total follow up of 8,506 patient-years (pt-yr) and a maximum of 41 years; by comparison, 1,309 valves were Current, with a total follow up of 11,586 pt-yr and a maximum of 36.1 MVR, were Discontinued, with a total follow up of 6,454 pt-yr and maximum of 37.2 years; and 771 valves were Current, with a total follow up of 6,211 pt-yr and maximum of 37.0 years. RESULTS: Kaplan-Meier (KM) survival at 10 years was 53% for AVR and 51% for MVR; KM survival at 20 years was 23% for both AVR and MVR; KM survival at 30 years was 8% for both AVR and MVR; KM survival at 40 years was 4% for AVR. The standard error for all KM percentages was 1%. Four patients are currently alive with their original valves, more than 40 years after implantation. CONCLUSION: This series of patients, who underwent valve replacement with the Starr-Edwards valve, now have a follow up extending beyond 40 years, thereby confirming the excellent durability of this valve.

Actuarial Analysis↗
PubMed2003

Continuous insulin infusion reduces mortality in patients with diabetes undergoing coronary artery bypass grafting.

OBJECTIVE: Diabetes mellitus is a risk factor for death after coronary artery bypass grafting. Its relative risk may be related to the level of perioperative hyperglycemia. We hypothesized that strict glucose control with a continuous insulin infusion in the perioperative period would reduce hospital mortality. METHODS: All patients with diabetes undergoing coronary artery bypass grafting (n = 3554) were treated aggressively with either subcutaneous insulin (1987-1991) or with continuous insulin infusion (1992-2001) for hyperglycemia. Predicted and observed hospital mortalities were compared with both internal and external (Society of Thoracic Surgeons 1996) multivariable risk models. RESULTS: Observed mortality with continuous insulin infusion (2.5%, n = 65/2612) was significantly lower than with subcutaneous insulin (5.3%, n = 50/942, P <.0001). Likewise, glucose control was significantly better with continuous insulin infusion (177 +/- 30 mg/dL vs 213 +/- 41 mg/dL, P <.0001). For internal comparison, multivariable analysis showed that continuous insulin infusion was independently protective against death (odds ratio 0.43, P =.001). Conversely, cardiogenic shock, renal failure, reoperation, nonelective operative status, older age, concomitant peripheral or cerebral vascular disease, decreasing ejection fraction, unstable angina, and history of atrial fibrillation increased the risk of death. For external comparison, observed mortality with continuous insulin infusion was significantly less than that predicted by the model (observed/expected ratio 0.63, P <.001). Multivariable analysis revealed that continuous insulin infusion added an independently protective effect against death (odds ratio 0.50, P =.005) to the constellation of risk factors in the Society of Thoracic Surgeons risk model. CONCLUSION: Continuous insulin infusion eliminates the incremental increase in in-hospital mortality after coronary artery bypass grafting associated with diabetes. The protective effect of continuous insulin infusion may stem from the effective metabolic use of excess glucose to favorably alter pathways of myocardial adenosine triphosphate production. Continuous insulin infusion should become the standard of care for glycometabolic control in patients with diabetes undergoing coronary artery bypass grafting.

Aged↗
PubMed2003

"Our complication rates are lower than theirs": statistical critique of heart valve comparisons.

OBJECTIVES: From the widely differing complication rates published for every heart valve, is it possible to determine a true rate for each valve and to compare the rates of two different valves? We investigated this question for the two most popular bileaflet valves. METHODS: Aortic valve data were abstracted from 14 St Jude Medical (St Jude Medical Inc, Minneapolis, Minn; 33,125 patient-y) and 11 Carbomedics (Sulzer Carbomedics Inc, Austin, Tex; 19,141 patient-y) series, and mitral valve data were abstracted from 11 St Jude Medical (21,553 patient-y) and 8 Carbomedics (8368 patient-y) series. Regression analysis was used to accommodate heterogeneity among rates with the same valve model, to estimate hazard ratios and 95% confidence intervals for the valve model effect, and to incorporate other series-level risk factors. RESULTS: Most of the complication rates with both valve models exhibited significant heterogeneity. For thromboembolism and bleeding, the relative risks for valve model were not significantly different from unity. Valve thrombosis rates exhibited less heterogeneity: the Carbomedics valve had a lower rate in the aortic position (hazard ratio 0.2, 95% confidence interval 0.1-0.6) and a higher rate in the mitral position (hazard ratio 1.9, 95% confidence interval 1.0-3.8). CONCLUSIONS: Unlike simple weighted averages of valve complication rates, regression methods can incorporate heterogeneity related to center effects and allow for inclusion of other risk factors. Thromboembolism and bleeding rates were not significantly different with St Jude Medical and Carbomedics valves. Valve thrombosis appeared to differ between the two valves, but the absolute differences in rates were small. Because of the variability among rates with the same valve, statistical comparisons must be interpreted cautiously.

Aortic Valve↗
PubMed2003

Statistical analysis of the results of heart valve replacement.

A variety of statistical methods can be used to analyze the results of heart valve replacement. In this review, we illustrate the methodology and the application of the techniques that are most widely used. For early events, univariate analysis and multivariate logistic regression are illustrated. For late (time-related) events, nonparametric methods (Kaplan-Meier and cumulative incidence or 'actual' analysis), parametric methods (based on the exponential, Gompertz and Weibull distributions) and semiparametric methods (Cox proportional hazards) are illustrated.

Aged↗
PubMed2002

Statistical analysis of heart valve outcomes.

Statistics is a rapidly growing field utilizing thousands of data analysis functions, though a relatively few are used in the majority of cardiac surgical studies. Dr. Wechsler recently published a list of the statistical terms which are important for cardiothoracic surgeons to be familiar with. These can be grouped into 3 categories: General concepts; Summary and test statistics; and Special techniques. The last category includes three techniques which are widely used to describe the long-term results of heart valve series: Hazard functions, Kaplan-Meier event-free curves, and "Actual" event-free curves. Some conclusions from a review of these techniques are: (1) an event with a non-constant hazard should not be described using "Linearized" rates (the Weibull distribution adds a parameter to accommodate changing hazard); (2) for non-fatal events, "Actual" analysis provides the true event probability, which the Kaplan-Meier overestimates. These methods are used in the analysis of published heart valve series to conclude that: (1) the wide scatter in complications rates with the same valve models implicates factors other than the valve; (2) the earliest porcine series had low mean ages and low durability compared with later series.

Heart Valve Diseases↗
PubMedDate not supplied

Effect of hyperglycemia and continuous intravenous insulin infusions on outcomes of cardiac surgical procedures: the Portland Diabetic Project.

OBJECTIVE: To describe the main findings of the Portland Diabetic Project, which elucidates the adverse relationship between hyperglycemia and outcomes of cardiac surgical procedures in patients with diabetes and delineates the protective effects of intravenous insulin therapy in reducing those adverse outcomes. RESULTS: In this ongoing 17-year prospective, nonrandomized, interventional study of 4,864 patients with diabetes who underwent an open-heart surgical procedure, we investigated the effects of hyperglycemia, and its subsequent reduction by continuous intravenous insulin (CII) therapy, on in-hospital outcomes. Increasing blood glucose levels were found to be directly associated with increasing rates of death, deep sternal wound infections (DSWI), length of hospital stay (LOS), and hospital cost. In separate multivariate analyses, increasing hyperglycemia was found to be independently predictive of increasing mortality (P<0.0001), DSWI (P = 0.017), and LOS (P<0.002). Conversely, CII therapy, designed to achieve predetermined target blood glucose levels, independently reduced the risks of death and DSWI by 57% and 66%, respectively (P<0.0001 for both). Target blood glucose levels of less than 150 mg/dL and a 3-day postoperative duration of CII therapy are both important variables that determine the effect of the CII therapy on improved outcomes. Coronary artery bypass grafting-related mortality (2.5%) and DSWI rates (0.8%) in patients with diabetes were normalized to those of the nondiabetic population by the use of the Portland CII Protocol. CONCLUSION: Perioperative hyperglycemia in patients undergoing a cardiac surgical procedure affects biochemical and physiologic functions, which, in turn, adversely alter mortality, LOS, and infection rates. The Portland CII Protocol is a cost-efficient method that effectively eliminates hyperglycemia and reduces postoperative morbidity and mortality in patients with diabetes undergoing an open-heart operation. CII protocols should be the standard care for glycometabolic control in all patients undergoing cardiac surgical procedures.

Blood Glucose↗