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The main objective of this article is to introduce a new natural fiber as a reinforcement in polymers for making composites for lightweight applications. The extraction of golden cane (Chrysalidocarpus lutescens) fiber and the mechanical properties of the fiber-reinforced polyester composites are described. The composites were formulated up to a maximum volume fraction of 0.43, resulting in a mean tensile strength and modulus of 2.13 and 2.26 times and mean flexural strength and modulus of 1.94 and 2.89 times greater than those of plain polyester, respectively, at a higher volume fraction of 0.43. The work of fracture in impact is measured to be 358 J/m. The results of this study indicate that golden cane fibers have potential as reinforcing fillers in plastics in order to produce inexpensive materials with high toughness.

Background The objective of our study was to evaluate the outcomes of open-heart surgery in patients with a spinal cord injury. Methods A retrospective analysis of all patients (n = 8) with a spinal cord injury who underwent open-heart operations in a single institution from April 1994 to November 2006 was conducted. Results All patients had a permanent spinal cord injury with levels ranging from T3 to L2 with a mean age of 62 years (range, 47–72). Seven coronary artery bypass operations and 2 aortic valve replacements were performed. The mean cardiac ejection fraction was 44% (range, 20–60). Seventy-five percent of the patients were extubated within 24 hours of the operation. A decubitus ulcer occurred in only 1 patient. The acute hospital stay averaged 14 days (range, 6–36). One patient died from multiorgan failure on postoperative day 13 giving an in-hospital 30-day mortality of 12.5%. The 5-year survival was 75% with a mean follow-up of 67 months (range, .5–129). Conclusions Open-heart operations in patients with a spinal cord injury can be performed safely with acceptable early and late outcomes.

A 62-year–old man presented with progressive exertional dyspnea and angina. His past medical history is notable for coronary artery disease, for which he underwent a coronary artery bypass graft surgery 8 years earlier. A few years afterward, he underwent aortic valve (AV) bypass (AVB) surgery for severe aortic stenosis (AS) using an apicoaortic conduit to the descending aorta consisting of a 16-mm connector and an 18-mm valved conduit (Hancock valve; Medtronic, Minneapolis, MN; Figures 1 and 2; online-only Data Supplement Movie I). After a period of initial improvement in symptoms, the patient developed progressive dyspnea and angina and was referred for additional cardiac workup. Figure 1. An ECG-gated thin-slice contrast-enhanced cardiac computed tomography scan showing a heavily calcified native aortic valve (AV), hypertrophied left ventricle (LV), and the apical LV insertion site of the apicoaortic valved conduit. Figure 2. A 3-dimensional cardiac computed tomography reconstruction image showing the apicoaortic valved conduit, extending from its apical insertion site into the left ventricle (LV) to its insertion site into the descending aorta. Arrow , Conduit valve. The patient underwent a bicycle ergometer test, which showed a diminished functional capacity and was stopped because of fatigue and a hypotensive response. He underwent a 2-dimensional transthoracic echocardiogram with gradual dobutamine infusion. He was found to have a heavily calcified AV (online-only Data Supplement Movie II) with a rest mean transvalvular gradient of 34 mm Hg and velocity of 3.5 m/s, which increased to 50 mm Hg and 4.8 m/s, respectively, at peak dobutamine dose (Figure 3). This corresponded with a …

Background The US Food and Drug Administration recently approved a transcatheter aortic valve for patients for whom open heart surgery is prohibitively risky. Methods A multidisciplinary heart valve team partnered with administration to launch a transcatheter aortic valve replacement (TAVR) program. Clinical registries were used to show robust valve caseloads and outcomes at our Veterans Affairs (VA) facility and to project future volumes. A TAVR business plan was approved by the VA leadership as part of a multiphase project to upgrade and expand our surgical facilities. Results The heart valve team completed a training program that included simulations and visits to established TAVR centers. Patients were evaluated and screened through a streamlined process, and the program was initiated successfully. Conclusions Establishing a TAVR program at a VA facility requires a multidisciplinary team with experience in heart valve and endovascular therapies and a supportive administration willing to invest in a sophisticated infrastructure.

Background The outcomes of thoracic aortic surgery involving hypothermic circulatory arrest at a US Department of Veterans Affairs medical center were evaluated. Methods Using the Veterans Affairs Continuous Improvement in Cardiac Surgery Program, all thoracic aortic operations performed with hypothermic circulatory arrest between December 1999 and December 2009 were identified (n = 24). Operative mortality and morbidity were evaluated, and survival was assessed by using the Kaplan-Meier method. Results Aortic dissection was the underlying disease in 10 patients (42%). Full or hemiarch aortic repair was performed in 16 patients (67%); of these operations, 3 (13%) involved elephant trunk repair. There was 1 operative death (4%). Four patients (17%) had strokes (all but 1 fully recovered), and 1 (4%) had renal failure. The survival rate was 90% at 1 year and 67% at 3 years. Conclusions Despite the magnitude and risk of thoracic aortic surgery involving hypothermic circulatory arrest, good outcomes can be achieved when such surgery is performed at an experienced Veterans Affairs center.

Papillary fibroelastomas are the most common benign neoplasms of the cardiac valvular structures, and they are being recognized more frequently because of higher-resolution imaging technology. Papillary fibroelastomas are associated with substantial complications that are secondary to systemic embolism. Incidentally discovered papillary fibroelastomas are treated on the basis of their size, mobility, and associated comorbidities and symptoms. Surgical resection should be offered to all patients who have symptoms and to asymptomatic patients who have pedunculated lesions or tumors larger than 1 cm in diameter. Valve-sparing excision produces good long-term results in most instances.Herein, we present the case of a patient who was scheduled for elective myocardial revascularization and in whom an aortic valve papillary fibroelastoma was discovered incidentally during routine intraoperative transesophageal echocardiography. The timely recognition of this asymptomatic tumor enabled a modified operative approach: the patient underwent myocardial revascularization with concomitant valve-sparing resection of the tumor. We discuss the pathophysiology of fibroelastomas of the aortic valve and operative approaches to the management of these tumors when they are discovered incidentally.

The relative prognostic impact of intra-aortic balloon pump (IABP) placement before versus after cardiac surgery is not well defined.We reviewed data from all cardiac surgical patients who received perioperative IABP support at a veterans' hospital between April 1992 and April 2008. We compared outcomes between patients who received an IABP before surgery (BS, n = 36) and after surgery (AS, n = 28).The AS group had higher operative morbidity (71% vs 42%) and mortality (43% vs 14%) rates than the BS group (P.02 for both). Furthermore, survival rates were lower in the AS group than in the BS group at 1 year (50% vs 83%) and 3 years (46% vs 80%) (log-rank test, P.004).Patients who require IABP after cardiac surgery may have worse outcomes than patients who receive IABP support before surgery. In both groups, after an early peak in mortality, the midterm outcomes were characterized by a reassuring plateau in the survival rates.

Background Because surgical residents' level of experience may be at its nadir early in the academic year, academic seasonality—or the "July effect"—could affect cardiac surgical outcomes. Methods Prospectively collected data from the Department of Veterans Affairs Continuous Improvement in Cardiac Surgery Program were used to identify 70,616 consecutive cardiac surgical procedures performed between October 1997 and October 2007. Morbidity and mortality rates were compared between early (July 1 to August 31, n=11,975) and late (September 1 to June 30, n=58,641) periods in the academic year. A prediction model was constructed by using stepwise logistic regression modeling. Results The two patient groups had similar demographic and risk variables. Isolated coronary artery bypass grafting accounted for 76.7% of early-period procedures and 75.8% of later-period procedures ( p = 0.03). Morbidity rates did not differ significantly between the early (14.0%) and later periods (14.2%; odds ratio [OR], 1.01; 95% confidence interval [CI], 0.96 to 1.07; p = 0.67) and operative mortality was similar, 3.7% vs 3.9% (OR, 0.99; 95% CI, 0.89 to 1.11; p = 0.90). The early portion of the year was associated with longer cardiac ischemia times (84 ± 40 vs 83 ± 42 minutes), cardiopulmonary bypass times (126 ±52 vs 124 ±56 minutes), and total surgical times (295 ± 90 vs 288 ± 90 minutes; p Conclusions The early part of the academic year was associated with slightly longer operative times; however, risk-adjusted outcomes were similar in both periods. This finding should lessen concerns about the quality of cardiac surgical care at the beginning of the academic year.

Hurricane Katrina produced a surge of patient referrals to our facility for cardiac surgery. We sought to determine the impact of this abrupt volume change on operative outcomes. Using our cardiac surgery database, which is part of the Department of Veterans Affairs' Continuous Improvement in Cardiac Surgery Program, we compared procedural outcomes for all cardiac operations that were performed in the year before the hurricane (Year A, 29 August 2004–28 August 2005) and the year after (Year B, 30 August 2005–29 August 2006). Mortality was examined as unadjusted rates and as risk-adjusted observed-to-expected ratios. We identified 433 cardiac surgery cases: 143 (33%) from Year A and 290 (67%) from Year B. The operative mortality rate was 2.8% during Year A (observed-to-expected ratio, 0.4) and 2.8% during Year B (observed-to-expected ratio, 0.6) (P = 0.9). We identified several factors that enabled our institution to accommodate the increase in surgical volume during the study period. We conclude that, although Hurricane Katrina caused a sudden, dramatic increase in the number of cardiac operations that were performed at our facility, good surgical outcomes were maintained.

Importance The US Food and Drug Administration recently approved the use of a transcatheter aortic valve in patients for whom traditional valve replacement surgery poses a high or prohibitive risk. Our hospital was one of the first Veterans Affairs facilities to launch a transcatheter aortic valve replacement (TAVR) program. Objective To evaluate our early experience with transfemoral TAVR. Design and Setting We retrospectively reviewed the records of all patients who underwent TAVR during the first year of our program at the Department of Cardiothoracic Surgery, Michael E. DeBakey Veterans Affairs Medical Center. Participants The mean (SD) age of the patients was 77 (9) years, and their mean (SD) Society of Thoracic Surgeons predicted risk of mortality score was 8.8 (10.7). Interventions All patients underwent TAVR with the SAPIEN transcutaneous valve. Main Outcome Measures We evaluated operative mortality and major operative morbidity (stroke, myocardial infarction, renal failure necessitating dialysis, and requirement for mechanical circulatory support, as well as vascular complications and requirement for permanent pacemaker), in addition to length of hospital stay and discharge status. Results Between December 21, 2011, and December 13, 2012, a total of 19 transfemoral TAVR procedures were performed at our center. Implantation was successful in all cases. There were no reports of operative (30-day) mortality, prosthetic valve endocarditis, renal failure necessitating dialysis, perioperative myocardial infarction or stroke, or conversion to surgical aortic valve replacement. Seven patients (37%) had mild paravalvular leak, 3 patients (16%) had moderate paravalvular leak, 2 patients (11%) had groin wound complications, 2 patients (11%) required a permanent pacemaker, 1 patient (5%) had a vascular access complication requiring endovascular repair, and 1 patient (5%) required temporary circulatory support (with extracorporeal membrane oxygenation). The mean (SD) length of hospital stay after TAVR was 8.0 (5.9) days. All patients were discharged home. Conclusions and Relevance Transcatheter aortic valve replacement can be performed safely and with good outcomes at a Veterans Affairs facility with a committed multidisciplinary team and substantial experience in heart valve and endovascular therapies.

Hypothesis We hypothesized that the relationship among β-blocker use, heart rate control, and perioperative cardiovascular outcome would be similar in patients at all levels of cardiac risk. Design Retrospective cohort study. Setting Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas. Patients Among all patients who underwent various noncardiac surgical procedures in 2000, those who received perioperative β-blockers were matched and compared with a control group from the same patient population. Main Outcome Measures Thirty-day stroke, cardiac arrest, myocardial infarction, and mortality, as well as mortality at 1 year. Results Patients at all levels of cardiac risk who received β-blockers had lower preoperative and intraoperative heart rates. The β-blocker group had higher rates of 30-day myocardial infarction (2.94% vs 0.74%, P =.03) and 30-day mortality (2.52% vs 0.25%, P =.007) compared with the control group. In the β-blocker group, patients who died perioperatively had significantly higher preoperative heart rate (86 vs 70 beats/min, P =.03). None of the deaths occurred among the patients at high cardiac risk. Conclusion Among patients at all levels of cardiac risk undergoing noncardiac surgery, administration of β-blockers should achieve adequate heart rate control and should be carefully monitored in patients who are not at high cardiac risk.