Fractured sternal wire causing a cardiac laceration.

BACKGROUND: Hemopericardium is a serious complication that can occur after cardiac surgery. While most post-operative causes are due to inflammation and bleeding, patients with broken sternal wires and an unstable sternum may develop hemopericardium from penetrating trauma. CASE PRESENTATION: We present the case of a 62-year-old male who underwent triple coronary bypass surgery and presented five months later with sudden anterior chest wall pain. Chest computed tomography revealed hemopericardium with an associated broken sternal wire that had penetrated into the pericardial space. The patient underwent a redo-sternotomy which revealed a 3.5 cm bleeding, jagged right ventricular laceration that correlated to the imaging findings of a fractured sternal wire projecting in the pericardial space. The laceration was repaired using interrupted 4 - 0 polypropylene sutures in horizontal mattress fashion between strips of bovine pericardium. The patient's recovery was uneventful and he was discharged on post-operative day four without complications. CONCLUSION: Patients with broken sternal wires and an unstable sternum require careful evaluation and management as these may have potentially life-threatening complications if left untreated.

A Case of Post-operative Jaundice After Cardiac Surgery.

Hyperbilirubinemia is a common gastrointestinal complication seen post-cardiac surgery. Here, we describe a case of a 72-year-old male with a past medical history of chronic obstructive pulmonary disease, chronic kidney disease (CKD), pulmonary hypertension, and valvular heart disease with severe aortic stenosis, severe mitral and tricuspid regurgitations who underwent elective aortic valve replacement (AVR), mitral valve replacement (MVR), and tricuspid valve (TV) repair; in addition, he required left thoracotomy for the repair of pulmonary artery perforation from a Swan-Ganz catheter that resulted in a large left pleural bleed. Post-operatively, he developed severe jaundice, which was predominantly conjugated that peaked at 24 mg/dL. He also required multiple blood products' transfusion in the perioperative period and was supported temporarily with hemodialysis for acute kidney injury superimposed on his CKD. He underwent extensive evaluation for jaundice, which included ultrasound of the liver, hepatobiliary iminodiacetic (HIDA) scan, and magnetic resonance cholangiopancreatography (MRCP), which were all normal. The patient eventually got better and was discharged from the hospital. The hyperbilirubinemia slowly got better without any specific therapy and on his follow-up visit to the office following discharge, his bilirubin level was found completely normalized. Although most cases of post-cardiac surgery hyperbilirubinemia resolve without any specific therapy, the occurrence is not completely benign since it can increase morbidity and mortality. It is paramount that intensivists and cardiothoracic surgeons caring for these patients are aware of this occurrence to prevent unnecessary diagnostic evaluation. Most early cases of hyperbilirubinemia are transient and do not usually increase morbidity and mortality. In the late cases, infectious etiology resulting in sepsis needs to be entertained early and treated aggressively.

A study on the influence of service robots' level of anthropomorphism on the willingness of users to follow their recommendations.

Service robots are increasingly deployed in various industries including tourism. In spite of extensive research on the user's experience in interaction with these robots, there are yet unanswered questions about the factors that influence user's compliance. Through three online studies, we investigate the effect of the robot anthropomorphism and language style on customers' willingness to follow its recommendations. The mediating role of the perceived mind and persuasiveness in this relationship is also investigated. Study 1 (n = 89) shows that a service robot with a higher level of anthropomorphic features positively influences the willingness of users to follow its recommendations while language style does not affect compliance. Study 2a (n = 168) further confirms this finding when we presented participants with a tablet vs. a service robot with an anthropomorphic appearance while communication style does not affect compliance. Finally, Study 2b (n = 122) supports the indirect effect of anthropomorphism level on the willingness to follow recommendations through perceived mind followed by persuasiveness. The findings provide valuable insight to enhance human-robot interaction in service settings.

Surgical management of aortic valve disease in the elderly: A retrospective comparative study of valve choice using propensity score analysis.

BACKGROUND AND AIM OF THE STUDY: Aortic valve dysfunction is the most common form of valvular heart disease. As the population continues to age, a greater number of patients will become candidates for aortic valve replacement (AVR); hence, prosthetic valve choice becomes of paramount importance. METHODS: A retrospective analysis was conducted on 801 patients aged > or =65 years who underwent isolated AVR or AVR + coronary artery bypass grafting (CABG) between January 1989 and June 2003 with a Carpentier Edwards Perimount (CEP) pericardial bioprosthesis (n = 398) or a St. Jude Medical (SJM) mechanical valve (n = 403). The mean age of CEP patients was 74.5 years (range: 65-89 years), and of SJM patients 73.9 years (range: 65-90 years). The follow up was 96.2% and 96.5% complete for CEP and SJM patients, respectively. Propensity scoring was used to establish homogeneity of the groups and reduce bias. RESULTS: The operative mortality was 4.0% (n = 16) among CEP patients and 6.5% (n = 26) among SJM patients. Predictors of hospital mortality included: peripheral vascular disease (p = 0.018), surgical urgency (p = 0.010), preoperative intra-aortic balloon pump (IABP) (p = 0.010), intraoperative perfusion time (p = 0.046) and intraoperative IABP (p = 0.001). Postoperative morbidities were similar for the two groups. The mean follow up was 72.4 and 59.2 months for CEP and SJM patients, respectively. The five-year actuarial survival was 70.9 +/- 2.3% for CEP and 71.8 +/- 2.4% for SJM patients; at 10 years the actuarial survival was 32.6 +/- 3.3% and 38.2 +/- 3.8%, respectively. Freedom from reoperation for AVR, stroke and non-fatal myocardial infarction was 98.8% (159/161), 99.4% (160/161) and 99.4% (160/161), respectively, in CEP patients, and 100.0% (220/220), 97.7% (215/220) and 97.7% (215/220), respectively, in SJM patients (p = NS). Predictors of late death (>30 days) included chronic obstructive pulmonary disease (p = 0.001) and mechanical valve replacement (p = 0.001). CONCLUSION: In comparable elderly patients, the outcomes of CEP and SJM valves after AVR showed no significant differences in hospital morbidity, mortality, mid-term survival or late cardiac events. However, the cumulative risk of lifelong anticoagulation with a mechanical valve is a serious consideration that must be factored into the selection algorithm.

Current clinical outcomes of percutaneous coronary intervention and coronary artery bypass grafting.

BACKGROUND: Randomized trials have compared coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI). However, results of these trials in select patients may not accurately reflect current clinical practice using drug-eluting stents (DES) and off-pump CABG. We undertook a prospective registry of coronary revascularization by CABG on-pump and off-pump, and PCI with or without DES, to determine clinical outcomes. METHODS: All patients undergoing isolated coronary revascularization in 8 community-based hospitals were enrolled. Preprocedural, intraprocedural, and postprocedural data were captured, with outcomes obtained at 18 months by patient and physician contact, and the Social Security Death Index. RESULTS: The study enrolled 4336 patients, 71.2% PCI and 28.8% CABG. DESs were used in 2249 PCIs (73.1%), and 596 CABG procedures (47.8%) were off-pump. Incidence of major adverse cardiac events at 18 months was 14.7% for CABG vs 23.3% for PCI (p < 0.001). Cardiac death and myocardial infarction had similar rates. The need for repeat revascularization was significantly less with CABG (6.2% vs 13.6%, p < 0.001). Hazard ratio of CABG to PCI was 0.76 (95% confidence interval, 0.571 to 0.872). CABG outcome was similar on-pump and off-pump, as was repeat revascularization with DES (12.1%) vs BMS (14.9%; p = 0.096). Overall event-free survival was 85.3% in CABG and 76.8% in PCI (p < 0.001). CONCLUSIONS: Rates of repeat revascularization were significantly higher for PCI than for CABG, but mortality and myocardial infarction were the same. There were no significant differences in outcomes between DES and BMS or between on-pump and off-pump CABG.

Routine use of the direct thrombin inhibitor bivalirudin for off-pump coronary artery bypass grafting is safe and effective.

Anticoagulation with unfractionated heparin has been the standard of care for more than a half-century for patients undergoing cardiac surgery. The risk of heparin-induced adverse reactions dictates the need for a safe and effective alternative, particularly in off-pump coronary artery bypass (OPCAB) surgery, an approach associated with a perioperative prothrombotic condition that may negatively influence graft patency. Between March 2003 and January 2005, 243 consecutive patients underwent OPCAB with bivalirudin (0.75 mg/kg bolus with 1.75 mg/kg per hour infusion). There were 171 men (70.4%) and 72 women (29.6%). The mean age was 64.9 +/- 10.9 years (age range 32-88 years). There were 147 patients (60.5%) with 3-vessel disease; 46 (18.9%) had substantial (>50%) stenosis of the left main coronary artery; 104 (42.8%) had a moderately reduced (0.30 to 0.50) ejection fraction; and 9 (3.7%) had a severely reduced (<0.30%) ejection fraction. Five patients (2.1%) required conversion to cardiopulmonary bypass and subsequently received heparin. Postoperative complications included perioperative myocardial infarction in 6 patients (2.5%), stroke in 3 (1.2%), prolonged ventilation in 4 (1.6%), reoperation for bleeding in 3 (1.2%), renal insufficiency in 14 (5.8%), atrial fibrillation in 26 (10.7%), low cardiac output in 3 (1.2%), and deep sternal infection in 1 (0.4%). Blood products were used in 117 patients (48.1%). The overall hospital mortality rate was 0.4% (1 of 243). Bivalirudin is a safe and effective anticoagulant that may be routinely used as an alternative to heparin and protamine in patients undergoing OPCAB. This is evidenced by low hospital mortality and morbidity rates. Further follow-up is warranted to discern the influence of bivalirudin on long-term clinical outcomes.

Coronary Artery Revascularization (CARE) registry: an observational study of on-pump and off-pump coronary artery revascularization.

BACKGROUND: The Coronary Artery Revascularization (CARE) study is a multicenter observational registry of coronary revascularization by percutaneous and surgical techniques. As a substudy of this registry, we analyzed the current practice and outcomes of on-pump and off-pump coronary artery bypass graft (CABG) surgery. METHODS: Procedural and outcomes data were prospectively collected for all patients undergoing isolated CABG in eight community-based hospitals in the HCA Hospital System between February 1 and July 31, 2004. Twelve-month follow-up was obtained by patient contact, phone, questionnaire, and the National Death Index. RESULTS: Isolated coronary artery revascularization procedures were done in 1251 patients, with 12-month follow-up data available on 1149 (91.8%); 654 patients (52.3%) were operated on-pump and 597 (47.7%) had off-pump procedures. On-pump versus off-pump results were mean number of grafts, 3.4 +/- 1 versus 2.9 +/- 1.2 (p < 0.001); operative mortality, 1.7% versus 1.7% (p = 1.00); permanent stroke, 0.9% versus 0.7% (p = 0.51); reoperation for bleeding, 2.6% versus 1.0% (p = 0.037); prolonged ventilation, 10.0% versus 3.4% (p < 0.001); atrial fibrillation, 23.8% versus 14.9% (p < 0.001); need for transfusion, 51.0% versus 34.9% (p < 0.001); intensive care unit length of stay, 68.1 +/- 97.0 hours versus 59.3 +/- 109.4 hours (p = 0.16); and hospital length of stay, 7.5 days versus 6.2 days (p < 0.001). At 12 months, there was no difference in total cardiac mortality on-pump versus off-pump (4.9% versus 4.6%, p = 0.88), myocardial infarction (1.0% versus 0.7%, p = 0.76), need for repeat revascularization (2.8% versus 4.1%, p = 0.70), or total overall major adverse cardiac outcomes (8.7 versus 9.4, p = 0.69). CONCLUSIONS: Current approaches to coronary revascularization using both on-pump and off-pump techniques at individual surgeon discretion, which varies significantly in the community setting, leads to acceptable outcomes. Although perioperative complications were less off-pump, mortality was the same, both in the perioperative period and at 12 months. Fewer grafts in the off-pump group appeared to be related to disease burden and not incomplete revascularization. Cardiac death, myocardial infarction, and the need for repeat revascularization were equal at 12 months.

Development of an empirical model to estimate real-world fine particulate matter emission factors: the traffic air quality model.

The purpose of the study was to quantify the impact of traffic conditions, such as free flow and congestion, on local air quality. The Borman Expressway (I-80/94) in Northwest Indiana is considered a test bed for this research because of the high volume of class 9 truck traffic traveling on it, as well as the existing and continuing installation of the Intelligent Transportation System (ITS) to improve traffic management along the highway stretch. An empirical traffic air quality (TAQ) model was developed to estimate the fine particulate matter (PM2.5) emission factors (grams per kilometer) based solely on the measured traffic parameters, namely, average speed, average acceleration, and class 9 truck density. The TAQ model has shown better predictions that matched the measured emission factor values more than the U.S. Environmental Protection Agency (EPA)-PART5 model. During congestion (defined as flow-speeds < 50 km/hr [30 mi/hr]), the TAQ model, on average, overpredicted the measured values only by a factor of 1.2, in comparison to a fourfold underprediction using the EPA-PART5 model. On the other hand, during free flow (defined as flow-speeds > 80 km/hr [50 mi/hr]), the TAQ model was conservative in that it overpredicted the measured values by 1.5-fold.

Is the St. Jude Medical mechanical valve an appropriate choice for elderly patients?: A long-term retrospective study measuring quality of life.

BACKGROUND AND AIM OF THE STUDY: The selection of a suitable valve substitute in patients requiring valvular heart surgery is an important element in the preoperative decision-making process between cardiologist, surgeon, and patient. Controversy persists regarding the use of mechanical valves in the elderly. With the population living longer, reoperative risk becomes of paramount importance. Quality of life (QOL) considerations are often as important to the patient as longevity. The influence of mechanical valve replacement on QOL in elderly patients has not been well documented. METHODS: Between June 1981 and December 1999, a total of 1,125 consecutive patients aged > or = 65 years (582 men, 543 women; mean age 71.4 +/- 4.9 years) underwent valve replacement with at least one St. Jude Medical (SJM) mechanical valve. Preoperatively, 138 patients (12.3%) were in NYHA class II, 775 (68.9%) in class III, and 212 (18.8%) in class IV. In 535 patients (47.6%), coronary artery disease required surgical intervention. Survivors were administered the Short Form (SF)-36 QOL Survey at follow up, which was 96.1% complete. RESULTS: Hospital mortality was 7.6% (85/1,125). Mean follow up was 5.9 years (range: 9 months to 18.4 years). Mean (+/- SEM) actuarial survival was 70.6 +/- 1.4% at five years, and 40.6 +/- 2.0% at 10 years. Male patients scored significantly higher on the SF-36 than controls in physical (p = 0.012) and mental health (p = 0.004). Comparing female patients with controls revealed no significant difference in physical health; however, they scored higher in mental health than controls (p = 0.001). CONCLUSION: The study results clearly demonstrate that heart surgery in the elderly with the SJM mechanical valve can be accomplished with acceptable hospital mortality, morbidity, and excellent long-term results. Moreover, long-term QOL in elderly patients with a SJM valve can be expected to meet or exceed that of age- and gender-matched controls.

Use of bivalirudin as an anticoagulant during cardiopulmonary bypass.

Bivalirudin is a short-acting direct thrombin inhibitor that has been used in cardiac surgical patients with heparin-induced thrombocytopenia (HIT) or suspected HIT. Although no direct thrombin inhibitor is indicated for anticoagulation during cardiac surgery in patients with heparin-induced thrombocytopenia (HIT) or suspected HIT, use of heparin-alternatives are increasing as the awareness of HIT increases. Reports of anticoagulation with bivalirudin are sporadic, however, with variable dosing and management strategies. In this report, we describe our management techniques for cardiopulmonary bypass with bivalirudin based upon our personal experience. Although the reported clinical experience with bivalirudin in cardiac surgery is reviewed, operative techniques for the perfusionist/surgeon team are discussed in detail. We recognize that the use of bivalirudin during cardiopulmonary bypass is evolving and modifications of technique will undoubtedly occur as further data and experience accumulate.

Midterm outcomes using the physio ring in mitral valve reconstruction: experience in 492 patients.

BACKGROUND: Mitral valve reconstruction using standardized Carpentier techniques is the treatment of choice for most patients with regurgitant lesions. Demonstrated predictability and stability make it an attractive alternative to valve replacement. The Physio Ring's inherent flexibility provides a viable alternative in the application of remodeling techniques and appears to be physiologically superior to traditional approaches. METHODS: Between April 1994 and October 2000, 492 consecutive patients underwent mitral valve reconstruction using standardized Carpentier techniques with the Carpentier-Edwards Physio Ring (Edwards Lifesciences LLC, Irvine, CA). There were 267 men (54.3%) and 225 women (45.7%). Mean age was 64.2 years (range, 18 to 86). Almost one-half (44.3%) were 70 years of age or over. The mitral valve etiology was congenital in 7 patients (1.4%), myxomatous in 351 patients (71.3%), ischemic in 88 (17.9%), rheumatic in 26 (5.3%), endocarditis in 9 (1.8%), calcific in 8 (1.6%), and other abnormalities in 3 (0.6%). RESULTS: Isolated mitral valve reconstruction was performed in 282 patients (57.3%), with coronary artery bypass grafting (CABG) in 182 (37.0%), with valve replacement in 11 (2.2%), and with CABG and valve replacement in 17 (3.5%). All patients (100.0%) had ring annuloplasty, 263 (53.5%) leaflet resection, 140 (28.5%) chordal resection, 55 (11.2%) chordal transposition, 48 (9.8%) chordal shortening, and 15 (3.0%) commissurotomy. Overall hospital mortality was 3.5% (17 of 492). Postoperative complications included respiratory insufficiency in 55 patients (11.2%), low cardiac output in 13 (2.6%), stroke in 14 (2.8%), reoperation for bleeding in 13 (2.6%), renal insufficiency in 21 (4.3%), and myocardial infarction in 5 (1.0%), and new onset of atrial fibrillation in 74 patients (15.0%). The cumulative follow-up for the series was 1,522.9 patient years and ranged from 1 to 101.0 months (mean, 38.5 months). There were 11 reconstruction failures (2.3%) requiring ring explant. Actuarial survival was 81.5% +/- 2.1% at 4 years and 67.9% +/- 4.6% at 7 years. Freedom from reoperation at 4 years was 81.5% +/- 2.1% and 67.9% +/- 4.6% at 7 years. CONCLUSIONS: Mitral valve reconstruction with the Physio Ring can be accomplished with low hospital mortality and morbidity even in combined procedures. Moreover, the low incidence of reoperation and late cardiac events suggests that the Physio Ring, with its inherent flexibility, offers a definite advantage in the application of remodeling techniques in mitral valve reconstruction.

Comparison of bovine and porcine heparin in heparin antibody formation after cardiac surgery.

BACKGROUND: Heparin-induced thrombocytopenia (HIT) is a potentially devastating complication of heparin therapy. The incidence of clinical HIT after cardiovascular surgery is less than 2%, although asymptomatic antibodies to heparin-platelet factor 4 (PF4) occur more frequently. Bovine heparin is thought to cause more HIT than porcine heparin, although this has never been established for heparin use during coronary artery bypass grafting. We therefore undertook a randomized, prospective study of heparin-PF4 antibody formation in patients undergoing first-time CABG given intraoperative bovine or porcine heparin. METHODS: Two hundred seven patients (108 porcine, 99 bovine) completed the study. Heparin given pre- or postoperatively was always porcine. Platelet counts and heparin-PF4 antibody tests (enzyme-linked immunosorbent assays) were performed preoperatively and daily until postoperative day 7 or discharge if earlier. RESULTS: The overall incidence of heparin-PF4 antibody formation was 42%. Six patients (2.9%) were positive preoperatively, of which, 1 developed clinical HIT. When these were excluded, seroconversion rates were 44 of 99 (44.4%) and 33 of 108 (30.6%) for bovine and porcine heparin, respectively (p = 0.041). Among patients who produced antibodies, most (90% bovine, 85% porcine) seroconverted after postoperative day 2. There were no differences in postoperative platelet counts; only 1 patient developed thrombosis associated with seroconversion, but without developing thrombocytopenia. The seroconversion rates for patients having cardiopulmonary bypass or off-pump surgery were not significantly different. CONCLUSIONS: This study confirms the high frequency of heparin-PF4 antibodies after coronary artery bypass grafting and demonstrates a significantly higher incidence after bovine heparin. However, because some patients may seroconvert after discharge, our study may underestimate the true incidence.