High Risk of Prosthetic Valve Endocarditis and Death After Valve Replacement Operations in Dialysis Patients.

BACKGROUND: Despite a high burden of dialysis access-related bloodstream infections and an increasing incidence of endocarditis, few data are available addressing the risk of prosthetic valve endocarditis (PVE) in the dialysis population. We sought to assess the risk of PVE and death after valve replacement operations in patients receiving long-term dialysis. METHODS: A matched retrospective cohort study was conducted comprising patients admitted for valve replacement operations at two university hospitals. Patients without dialysis were matched 1:1 with dialysis patients by valve(s) replaced, year of operation, and presence of active endocarditis as the indication for valve replacement. Patient characteristics were compared using χ(2) and t tests. The development of PVE was defined by use of the modified Duke criteria and analyzed with Cox proportional hazards regression. RESULTS: Two hundred seventy-eight patients were included, with 139 in either cohort. The PVE risk per year of follow-up was 0.14 in the dialysis cohort and 0.03 in the nondialysis cohort. Dialysis remained a risk factor (adjusted hazard ratio 5.61 [95% confidence interval, 2.17 to 14.5], p = 0.0004) after age and race were controlled for. The 5-year survival rate was lower after valve replacement operation in the dialysis group (25.4%) than in the nondialysis group (75.9%, p < 0.001). CONCLUSIONS: The risk of PVE and death after valve replacement operations in dialysis patients is substantial and significantly higher than in patients without dialysis. These findings highlight the importance of a careful preoperative risk-benefit assessment and underscore the need to prevent hemodialysis-related bloodstream infections.

Multidrug-Resistant Organism Infections in Patients with Left Ventricular Assist Devices.

Left ventricular assist devices improve survival prospects in patients with end-stage heart failure; however, infection complicates up to 59% of implantation cases. How many of these infections are caused by multidrug-resistant organisms is unknown. We sought to identify the incidence, risk factors, and outcomes of multidrug-resistant organism infection in patients who have left ventricular assist devices. We retrospectively evaluated the incidence of multidrug-resistant organisms and the independent risk factors associated with them in 57 patients who had permanent left ventricular assist devices implanted at our institution from May 2007 through October 2011. Outcomes included death, transplantation, device explantation, number of subsequent hospital admissions, and number of subsequent admissions related to infection. Infections were categorized in accordance with criteria from the Infectious Diseases Council of the International Society for Heart and Lung Transplantation. Multidrug-resistant organism infections developed in 18 of 57 patients (31.6%)-a high incidence. We found 3 independent risk factors: therapeutic goal (destination therapy vs bridging), P=0.01; body mass index, P=0.04; and exposed velour at driveline exit sites, P=0.004. We found no significant differences in mortality, transplantation, or device explantation rates; however, there was a statistically significant increase in postimplantation hospital admissions in patients with multidrug-resistant organism infection. To our knowledge, this is the first report in the medical literature concerning multidrug-resistant organism infection in patients who have permanent left ventricular assist devices.

Outcomes for Transcatheter Aortic Valve Replacement in Nonagenarians.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) may offer extreme-aged patients a treatment alternative to surgical aortic valve replacement (SAVR). The objective of this study was to describe outcomes of TAVR in nonagenarians using transfemoral and alternative access techniques. METHODS: In a retrospective review, we found 95 nonagenarians who underwent TAVR from September 2007 through February 2014 at Emory University using a balloon expandable valve: transfemoral (n = 66), transapical (n = 14), transaortic (n = 14), and transcarotid (n = 1). Morbidity and 30-day and midterm mortality were assessed. Kaplan-Meier plots were used to determine midterm survival rates. RESULTS: The mean age of the patients was 91.8 ± 1.8 years, and 49 (52%) were female. Postoperative morbidity included 1 patient (1%) each with stroke, myocardial infarction, pneumonia, and renal failure. The mean postoperative length of stay was 6.8 ± 5.1 days for all patients. Overall 30-day mortality was 3.2%, much less than The Society of Thoracic Surgeons predicted risk of mortality of 14.5% ± 7.3%. There were no deaths in the transfemoral patients, but there were 2 transapical deaths (14.3%) and 1 transaortic death (7.1%). The Kaplan-Meier estimate of median survival was 2.6 years. CONCLUSIONS: Extreme-aged nonagenarian patients may have excellent outcomes from TAVR at 30-day and midterm follow-up. Alternative access TAVR is associated with higher morbidity and mortality than transfemoral TAVR. Referral for TAVR of nonagenarians should not be precluded based on age alone.

Prospective Evaluation of Weight-Based Prophylactic Enoxaparin Dosing in Critically Ill Trauma Patients: Adequacy of AntiXa Levels Is Improved.

Venous thromboembolism (VTE) is a leading cause of death in multisystem trauma patients; the importance of VTE prevention is well recognized. Presently, standard dose enoxaparin (30 mg BID) is used as chemical prophylaxis, regardless of weight or physiologic status. However, evidence suggests decreased bioavailability of enoxaparin in critically ill patients. Therefore, we hypothesized that a weight-based enoxaparin dosing regimen would provide more adequate prophylaxis (as indicated by antifactor Xa levels) for patients in our trauma intensive care unit (TICU).These data were prospectively collected in TICU patients admitted over a 5-month period given twice daily 0.6 mg/kg enoxaparin (actual body weight). Patients were compared with a historical cohort receiving standard dosing. Anti-Xa levels were collected at 11.5 hours (trough, goal ≥ 0.1 IU/mL) after each evening administration. Patient demographics, admission weight, dose, and daily anti-Xa levels were recorded. Patients with renal insufficiency or brain, spine, or spinal cord injury were excluded. Data were collected from 26 patients in the standard-dose group and 37 in the weight-based group. Sixty-four trough anti-Xa measurements were taken in the standard dose group and 74 collected in the weight-based group. Evaluating only levels measured after the third dose, the change in dosing of enoxaparin from 30 to 0.6 mg/kg resulted in an increased percentage of patients with goal antifactor Xa levels from 8 per cent to 61 per cent (P < 0.0001). Examining all troughs, the change in dose resulted in an increase in patients with a goal anti-Xa level from 19 to 59 per cent (P < 0.0001). Weight-based dosing of enoxaparin in trauma ICU patients yields superior results with respect to adequate anti-Xa levels when compared with standard dosing. These findings suggest that weight-based dosing may provide superior VTE prophylaxis in TICU patients. Evaluation of the effects of this dosing paradigm on actual VTE rate is ongoing at our institution.

High-risk patients with inoperative aortic stenosis: use of transapical, transaortic, and transcarotid techniques.

BACKGROUND: Patient characteristics and procedural outcomes from nontransfemoral (non-TF) transcatheter aortic valve replacement (TAVR) in high-risk or inoperable patients with aortic stenosis have been incompletely reported. The purpose of this study was to compare outcomes with non-TF TAVR access techniques including transapical (TA), transaortic (TAo), and transcarotid (TC) TAVR with a balloon-expandable valve. METHODS: A retrospective review was performed of all patients undergoing TA, TAo, and TC TAVR from 2007 to 2013 at Emory University. Preoperative risk factors and postoperative outcomes were evaluated using Valve Academic Research Consortium-2 definitions. RESULTS: Of 469 patients undergoing TAVR during that period at our institution, 139 underwent TA TAVR, 35 had Tao TAVR, and 11 had TC TAVR. Patients undergoing TC TAVR were younger than those undergoing TA TAVR and TAo TAVR (mean ages: TC, 68.9 ± 23.6 years; TA, 81.3 ± 7.7 years; Tao, 83.8 ± 8.3 years; p = 0.017). Most patients undergoing TAo TAVR were women (82.9%), whereas patients undergoing TA TAVR were more likely to be men (62.6%). Slightly more than half of patients undergoing TA TAVR (54.7%) and TC (54.6%) TAVR had undergone previous coronary artery bypass grafting (CABG), whereas no patients underwent TAo TAVR (0%). There was no preoperative difference in ejection fraction, New York Heart Association classification, significant chronic obstructive pulmonary disease, and The Society of Thoracic Surgeons predicted risk of mortality between TA TAVR, Tao TAVR, and TC TAVR, respectively. Average postoperative length of stay was 9 to 11 days and was similar among groups (p = 0.22). There were 13 (9.4%) TA TAVR operative deaths and 4 (11.4%) operative deaths in the TAo TAVR group. There were no deaths in the TC TAVR group. CONCLUSIONS: In high-risk and inoperable patients who are not candidates for TF TAVR, careful selection of alternative access options can lead to excellent and comparable postoperative outcomes.

Avoiding aortic clamping during coronary artery bypass grafting reduces postoperative stroke.

OBJECTIVE: The purpose of this study was to determine whether the incidence of postoperative stroke could be reduced by eliminating aortic clamping during coronary artery bypass grafting. METHODS: From 2002 to 2013, 12,079 patients underwent primary, isolated coronary artery bypass grafting at a single US academic institution. Aortic manipulation was completely avoided by using in situ internal thoracic arteries for inflow in 1552 patients (12.9%) (no-touch), a clampless facilitating device for proximal anastomoses in 1548 patients (12.8%), and aortic clamping in 8979 patients (74.3%). These strategies were assessed in a logistic regression model controlling for relevant variables. RESULTS: The overall incidence of postoperative stroke was 1.4% (n = 165), with an unadjusted incidence of 0.6% (n = 10) in the no-touch group, 1.2% (n = 18) in the clampless facilitating device group, and 1.5% (n = 137) in the clamp group (P < .01 for no-touch vs clamp). The ratio of observed to expected stroke rate increased as the degree of aortic manipulation increased, from 0.48 in the no-touch group, to 0.61 in the clampless facilitating device group, and to 0.95 in the clamp group. Aortic clamping was independently associated with an increase in postoperative stroke compared with a no-touch technique (adjusted odds ratio, 2.50; P < .01). When separated by cardiopulmonary bypass use, both the off-pump partial clamp and the on-pump crossclamp techniques increased the risk of postoperative stroke compared with no-touch (adjusted odds ratio, 2.52, P < .01; and adjusted odds ratio, 4.25, P < .001, respectively). CONCLUSIONS: A no-aortic touch technique has the lowest risk for postoperative stroke for patients undergoing coronary artery bypass grafting. Clamping the aorta during coronary artery bypass grafting increases the risk of postoperative stroke, regardless of the severity of aortic disease.

Reduced intraocular pressure after cataract surgery in patients with narrow angles and chronic angle-closure glaucoma.

PURPOSE: To evaluate the effect of cataract surgery on intraocular pressure (IOP) in patients with narrow angles and chronic angle-closure glaucoma (ACG) and to determine whether the change in IOP was correlated with the preoperative pressure, axial length (AL), and anterior chamber depth (ACD). SETTING: Private practice, Atlanta, Georgia, USA. DESIGN: Retrospective case series. METHODS: Charts of patients with narrow angles or chronic ACG who had cataract surgery were reviewed. All eyes had previous laser iridotomies. Data recorded included preoperative and postoperative IOP, AL, and ACD. The preoperative IOP was used to stratify eyes into 4 groups. RESULTS: The charts of 56 patients (83 eyes) were reviewed. The mean reduction IOP in all eyes was 3.28 mm Hg (18%), with 88% having a decrease in IOP. There was a significant correlation between preoperative IOP and the magnitude of IOP reduction (r = 0.68, P < .001). The mean decrease in IOP was 5.3 mm Hg in eyes with a preoperative IOP above 20 mm Hg, 4.6 mm Hg in the over 18 to 20 mm Hg group, 2.5 mm Hg in the over 15 to 18 mm Hg group, and 1.4 mm Hg in the 15 mm Hg or less group. The mean follow-up was 3.0 years ± 2.3 (SD). CONCLUSIONS: Cataract surgery reduced IOP in patients with narrow angles and chronic ACG. The magnitude of reduction was highly correlated with preoperative IOP and weakly correlated with ACD. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

Transcatheter aortic valve replacement has improved short-term but similar midterm outcomes in isolated aortic valve replacement after prior coronary artery bypass grafting.

BACKGROUND: An increasing number of patients with prior coronary artery bypass grafting (CABG) now present with severe aortic stenosis. The proposed benefit of surgical (SAVR) vs transcatheter aortic valve replacement (TAVR) is unknown. The objective of this study was to compare short-term and midterm outcomes of patients undergoing isolated SAVR vs TAVR in those with prior CABG. METHODS: A retrospective analysis was performed of 255 patients who underwent isolated SAVR after prior CABG from January 2002 to February 2013 at Emory University. Outcomes of 148 patients undergoing SAVR (2002 to 2013) and 107 undergoing TAVR (2007 to 2013) were compared using multivariable logistic regression and analysis of variance techniques, adjusting for The Society of Thoracic Surgeons (STS) risk score. Kaplan-Meier plots were used to determine survival rates, and midterm survival between groups was compared using the Cox proportional hazards model. RESULTS: TAVR patients were older (79.8 ± 7.9 years vs 72.5 ± 8.8 years, p < 0.001) but were gender equivalent (female: 24% vs 22%, p = 0.61). The preoperative ejection fraction was similar between groups (TAVR: 0.433 ± 0.131 vs SAVR: 0.469 ± 0.148%, p = 0.60). The TAVR group had a significantly higher the STS risk scores (11.8% vs 7.1%, p < 0.001). All-cause 30-day mortality was 1.9% for TAVR and 4.1% for SAVR (p = 0.32), a result that marginally favors TAVR after risk adjustment (adjusted odds ratio, 0.19; p = 0.07). Postoperative morbidity and resource utilization was significantly higher in the SAVR patients. Midterm survival was similar between the two groups after adjustment (adjusted hazard ratio, 0.78, p = 0.46). CONCLUSIONS: Excellent outcomes can be achieved in SAVR or TAVR after prior CABG. Although TAVR improves short-term outcomes and resource utilization compared with SAVR, midterm mortality outcomes are similar.

Intrapyloric botulinum injection increases postoperative esophagectomy complications.

BACKGROUND: Intrapyloric botulinum toxin injection has emerged as a possible alternative to standard pyloric drainage procedures. Possible advantages include decreased operative time and less postoperative dumping and bile reflux symptoms. However, data are lacking to show its effectiveness versus standard drainage procedures. The purpose of this review is to compare the results in a prospective cohort of patients who received pyloric botulinum injection versus patients who received pyloromyotomy or pyloroplasty with esophagectomy. METHODS: We performed a retrospective review of a prospective database of all patients who underwent an open esophageal resection at a single institution from 2005 through 2010. Three hundred twenty-two patients were divided into 3 groups for analysis: botulinum injection (n = 78), pyloromyotomy (n = 45), and pyloroplasty (n = 199). We compared these groups with respect to duration of the procedure, presence of delayed gastric emptying on postoperative swallow studies, requirement of anastomotic dilation, requirement of pyloric dilation, use of postoperative promotility agents, and patient experience of postoperative symptoms of reflux or dumping, or both. RESULTS: Patients receiving botulinum injections experienced similar delayed gastric emptying on postoperative radiologic evaluation as did patients undergoing pyloromyotomy and pyloroplasty (16% versus 5% and 13%, respectively; p = 0.14). Mean operative time was significantly shorter for the patients receiving botulinum as expected (239 minutes versus 312 minutes and 373 minutes, respectively; p < 0.001). However, more patients receiving botulinum and pyloric dilation (22% versus 4% and 2%, respectively; p < 0.001) experienced postoperative reflux symptoms (32% versus 12% and 13%, respectively; p = 0.001) and used postoperative promotility agents (22% versus 5% and 15%, respectively; p = 0.04). There was no statistical difference between the groups regarding postoperative dumping. CONCLUSIONS: Use of intrapyloric botulinum injection significantly decreased operative time. However, the patients receiving botulinum experienced more postoperative reflux symptoms, had increased use of promotility agents as well as a requirement for postoperative endoscopic interventions, and postoperative dumping was not reduced by the reversible procedure. Intrapyloric botulinum injection should not be used as an alternative to standard drainage procedures. Pyloromyotomy appears to be the drainage procedure of choice to accompany an esophagectomy.

The impact of clopidogrel therapy on postoperative bleeding after robotic-assisted coronary artery bypass surgery.

OBJECTIVES: The purpose of this study was to determine whether patients undergoing robotic-assisted coronary artery bypass graft surgery (CABG) on clopidogrel had an increased risk of bleeding complications compared with those not on clopidogrel. METHODS: From 2008 to 2011, 322 patients underwent robotic-assisted CABG either as an isolated procedure or as part of a hybrid coronary revascularization procedure (HCR). Patients were classified according to whether they received clopidogrel within 5 days of surgery or intraoperatively (n = 64) compared with those who never received or who had discontinued clopidogrel therapy >5 days before surgery (n = 258). A propensity analysis using 31 preoperative variables was used to control for confounding variables. In a subgroup analysis, patients undergoing one-stage HCR (clopidogrel load 600 mg in odds ratio (OR) prior to stenting) were compared with patients in the clopidogrel group who underwent two-stage HCR. RESULTS: In the Clopidogrel group, the mean interval between surgery and last dose of clopidogrel was 2.1 ± 1.5 days. Compared with the No Clopidogrel group, the Clopidogrel group had greater 24-h chest tube drainage (1003 ± 572 vs 782 ± 530 ml, P = 0.004) and more blood transfusions (35.9%, 23 of 64 patients vs 20.9%, 54 of 258 patients, P = 0.01). On logistic regression analysis, there was greater 24-h chest tube drainage in the Clopidogrel group (+198 ml, P = 0.02) and a significantly higher incidence of blood transfusion (OR = 2.30, P = 0.01). In the subgroup analysis, patients undergoing one-stage HCR (n = 17) had greater 24-h chest tube drainage compared with patients undergoing two-stage HCR (1262 vs 909 ml, P = 0.03). CONCLUSIONS: Patients undergoing robotic-assisted CABG on clopidogrel had more postoperative bleeding and a higher incidence of blood transfusion. Therefore, despite a less invasive approach, surgery should be delayed in these patients when possible.

Incidence of postoperative stroke using the Heartstring device in 1,380 coronary artery bypass graft patients with mild to severe atherosclerosis of the ascending aorta.

BACKGROUND: Atherosclerotic disease of the ascending aorta during coronary artery bypass graft surgery (CABG) increases the risk for postoperative stroke. The objective of this study was to examine the incidence of postoperative stroke in CABG utilizing the Heartstring (Maquet Cardiovascular, San Jose, CA) proximal anastomotic device. METHODS: Intraoperative epiaortic ultrasonography was used to grade atherosclerosis in CABG patients at Emory University from April 2003 to December 2012. The Heartstring device was utilized in 1,380 patients: 407 (29.5%) grade I (minimal atherosclerosis), 367 (26.6%) grade II, 437 (31.7%) grade III, 110 (8.0%) grade IV, and 59 (4.3%) grade V (severe atherosclerosis). Logistic regression analysis was used to estimate the effect of aortic grade on outcomes adjusted for Society of Thoracic Surgeons predicted risk of mortality and predicted risk of stroke scores. RESULTS: The mean age of all patients was 66.7 ± 10.5 years, and 31.9% were female. An increasing risk profile was apparent with rising aortic grade. Most CABG was done off pump (n = 1,277, 92.5%). There was no significant association between aortic grade and frequency of postoperative stroke (p = 0.83). In all patients, use of the Heartstring device reduced the predicted risk of stroke by 44% (O:E risk 0.56). The benefit for postoperative stroke was least apparent in the grade I aorta patients (O:E 0.8) compared with patients having grade II and greater. There were no strokes among patients with severe atherosclerosis using the Heartstring device. CONCLUSIONS: Compared with the Society of Thoracic Surgeons predicted risk for stroke, the Heartstring proximal anastomotic device can be safely used with all aortic grades. The most prominent benefit appears to be for patients with grade II disease and greater.

Comparison of injury mortality risk in motor vehicle crash versus other etiologies.

The mortality risk ratio (MRR), a measure of the proportion of people who died that sustained a given injury, is reported to be among the most powerful discriminators of mortality following trauma. The primary aim was to determine whether mechanistic differences exist and are quantifiable when comparing MRR-based injury severity across two broadly defined etiologies (motor vehicle crash (MVC) versus non-MVC) for the clarification of important injury types that have some room for improvement by emergency treatment and vehicle design. All International Classification of Diseases, 9th revision (ICD-9) coded injuries in the National Trauma Data Bank (NTDB) database were stratified into MVC and non-MVC groups and the MRR for each injury was computed within each group. Injuries were classified as 11 different types for MRR comparison between etiologies. Overall, MRRs for specific injuries were 10-18% lower for MVC compared to non-MVC etiologies. MVCs however produced much higher mean MRRs for crushing injuries (0.184 versus 0.072) and internal injuries to the thorax, abdomen, and pelvis (0.200 versus 0.169). Non-MVCs produced much higher MRRs for intracranial injuries (0.199 versus 0.250). Analysis of the top 95% most frequent MVC injuries revealed higher MVC MRR values for 78% of the injuries with MRR ratios indicating an average 50% increase in a given injury's MRR when MVC was the etiology. Addressing the large differences in MRR in between etiologies for identical injuries could provide a reduction in fatalities and may be important to patient triage and vehicle safety design.

The impact of hybrid coronary revascularization on hospital costs and reimbursements.

BACKGROUND: Hybrid coronary revascularization (HCR) combines a minimally invasive, left internal mammary artery-left anterior descending coronary artery (LAD) bypass with percutaneous intervention of non-LAD vessels for patients with multivessel coronary disease. The financial implications of HCR have not been compared with off-pump coronary artery bypass (OPCAB) through sternotomy. METHODS: The contribution margin is a fiduciary calculation (best hospital payment estimate--total variable costs) used by hospitals to determine fiscal viability of services. From 2010 to 2011, 26 Medicare patients underwent HCR at a single United States institution and were compared with 28 randomly selected, contemporaneous Medicare patients undergoing multivessel OPCAB. All HCR patients underwent a robotic-assisted, sternal-sparing, off-pump, left internal mammary artery-LAD anastomosis plus percutaneous intervention to non-LAD vessels. A linear regression model was used to compare fiscal and utilization outcomes of HCR to OPCAB adjusted for hospital length of stay and The Society of Thoracic Surgeons Predicted Risk of Mortality score. RESULTS: On regression analysis controlling for overall length of stay and Predicted Risk of Mortality score, the contribution margin (+$8,771, p<0.0001) was greater for HCR than for OPCAB. Despite higher total cost for HCR compared with OPCAB (+$7,026, p=0.001), the total variable cost (+$2,281, p=0.07) was not significantly different. Best payment estimates (+11,031, p<0.0001) and Medicare reimbursements (+$8,992, p=0.002) were higher for HCR than for OPCAB, and there was a reduction in blood transfusion (-1.5 units, p<0.0001), ventilator time (-10 hours, p=0.001), and postoperative length of stay (-1.2 days, p=0.002) for the HCR group. CONCLUSIONS: Compared with OPCAB, HCR results in a greater contribution margin for hospitals. This may result from higher reimbursement as well as improved resource utilization postoperatively, which may offset more expensive procedural costs associated with HCR.

Total arch replacement using moderate hypothermic circulatory arrest and unilateral selective antegrade cerebral perfusion.

OBJECTIVE: To examine the clinical outcomes and impact of using moderate hypothermic circulatory arrest (MHCA) and unilateral selective antegrade cerebral perfusion (uSACP) in the setting of total aortic arch replacement (TOTAL). METHODS: From 2004 to 2012, 733 patients underwent open arch reconstruction with MHCA and SACP. Of these, 145 (20%) underwent TOTAL. Measured outcomes included death, stroke, temporary neurologic dysfunction (TND), and renal failure. Mean follow-up time was 33 months and ranged from 0 to 95 months. RESULTS: Core temperature at the onset of MHCA was 25.8°C. Cardiopulmonary bypass and myocardial ischemic times were 236 minutes and 181 minutes, respectively. Twenty-three patients (16%) underwent emergency repair of acute type A dissection. Fifty-four cases (37%) were reoperative and 52 (34%) were stage I elephant trunk procedures. Concomitant root replacement was performed in 50 (35%) patients, including 20 David V valve-sparing procedures. Mean duration of circulatory arrest was 55 minutes. Operative mortality was 9.7%. Overall incidence of stroke and TND was 2.8% and 5.6%, respectively. Four patients (2.8%) required postoperative dialysis. Seven-year survival was significantly reduced (P = .04) after repair of type A dissection (83.8%) compared with elective surgery (89.5%). Higher temperature during TOTAL was not found to be a significant risk factor for adverse events. CONCLUSIONS: TOTAL using MHCA and uSACP can be accomplished with excellent early and late results. MHCA was not associated with adverse neurologic outcomes or higher operative risk, despite prolonged periods of circulatory arrest.

Trends in aortic clamp use during coronary artery bypass surgery: effect of aortic clamping strategies on neurologic outcomes.

OBJECTIVE: The purpose of the present study was to determine the effect of different clamping strategies during coronary artery bypass grafting on the incidence of postoperative stroke. METHODS: In the present case-control study, all patients at Emory hospitals from 2002 to 2009 with postoperative stroke after isolated coronary artery bypass grafting (n = 141) were matched 1:4 to a contemporaneous cohort of patients without postoperative stroke (n = 565). The patients were matched according to the Society of Thoracic Surgeons' predicted risk of postoperative stroke score, which is based on 26 variables. The patients who received on-pump and off-pump coronary artery bypass grafting were matched separately. Multiple logistic regression analysis with adjusted odds ratios was performed to identify the operative variables associated with postoperative stroke. RESULTS: Among the on-pump cohort, the single crossclamp technique was associated with a decreased risk of stroke compared with the double clamp (crossclamp plus partial clamp) technique (odds ratio, 0.385; P = .044). Within the on-pump cohort, no significant difference was seen in the incidence of stroke according to clamp use. Epiaortic ultrasound of the ascending aorta increased from 45.3% in 2002 to 89.4% in 2009. From 2002 to 2009, clamp use decreased from 97.7% of cases to 72.7%. CONCLUSIONS: During on-pump coronary artery bypass grafting, the use of a single crossclamp compared with the double clamp technique decreased the risk of postoperative stroke. The use of any aortic clamp decreased and epiaortic ultrasound use increased from 2002 to 2009, indicating a change in the operative technique and surgeon awareness of the potential complications associated with manipulation of the aorta.

Long-term survival for patients with metabolic syndrome after bioprosthetic or mechanical valve replacement.

BACKGROUND: Metabolic diseases are thought to negatively impact the long-term survival of cardiac patients and have been shown to be associated with reduced durability of bioprosthetic heart valves. The purpose of this study is to determine whether long-term survival of post-valve replacement patients is affected by the presence of metabolic disease, and whether choice of tissue versus mechanical prosthesis impacts survival. METHODS: A retrospective review was conducted of all isolated valve replacements performed between 2002 and 2011 from the STS adult cardiac database of Emory Healthcare Hospitals. A total of 1,222 cases were reviewed, of which 909 patients had AVR (661 tissue, 248 mechanical), and 313 MVR (190 tissue, 123 mechanical). Cardiometabolic syndrome (CMS), in accordance with the World Health Organization (WHO) definition, was present in 242 of 1,222 (19.8%) cases in entire cohort, 203 of 909 (22.3%) in AVR, and 39 of 313 (12.5%) in MVR. Cox proportional hazard regression analysis was used to calculate long-term survival after adjusting for propensity score (PS), Society of Thoracic Surgeons Predicted Risk of Mortality (STS PROM), and direct covariates for valve and implant type and stratifying by CMS. RESULTS: In PS adjusted AVR, patients with CMS risk factors had worse survival compared to metabolic risk-free patients (AHR = 3.47), as was the case for MVR (AHR = 4.06). Tissue MVR patients with CMS had higher hazard of death compared to patients with no diabetes and no metabolic risk factors after adjusting for PROM (AHR = 3.33) and direct covariates (AHR = 3.91). CONCLUSIONS: Metabolic diseases negatively impact long-term survival of aortic and mitral valve replacement (MVR) patients. Tissue prostheses are associated with worse long-term survival following MVR.

The accuracy of transit time flow measurement in predicting graft patency after coronary artery bypass grafting.

OBJECTIVE: Transit time flow measurement (TTFM) is a method used to assess intraoperative blood flow after vascular anastomoses. Angiography represents the criterion standard for the assessment of graft patency after coronary artery bypass grafting (CABG). The purpose of this study was to compare flow measurements from TTFM to diagnostic angiography. METHODS: From October 9, 2009, to April 30, 2012, a total of 259 patients underwent robotic-assisted CABG procedures at a single institution. Of these, 160 patients had both TTFM and either intraoperative or postoperative angiography of the left internal mammary artery to the left anterior descending coronary artery graft. Transit time flow measurements were obtained after completion of the anastomosis and after administration of protamine before chest closure. Transit time flow measurement assessment included pulsatility index, diastolic fraction, and flow (milliliters per minute). Angiograms were graded according to the Fitzgibbon criteria. The patients were grouped according to angiographic findings, with perfect grafts defined as FitzGibbon A and problematic grafts defined as either Fitzgibbon B or O. RESULTS: Overall, there were 152 (95%) of 160 angiographically perfect grafts (FitzGibbon A). Of the eight problematic grafts, five were occluded (Fitzgibbon O) and three had significant flow-limiting lesions (FitzGibbon B). Two patients had intraoperative graft revision after completion angiography, one had redo CABG during the same hospitalization, and five were treated with percutaneous coronary intervention. A significant difference was seen in mean ± SD flow (34.3 ± 16.8 mL/min vs 23.9 ± 12.5 mL/min, P = 0.033) between patent and nonpatent grafts but not in pulsatility index (1.98 ± 0.76 vs 1.65 ± 0.48, P = 0.16) or diastolic fraction (73.5% ± 8.45% vs 70.9% ± 6.15%, P = 0.13). CONCLUSIONS: Although TTFM can be a useful tool for graft assessment after CABG, false negatives can occur. Angiography remains the criterion standard to assess graft patency and quality of the anastomosis after CABG.

Improved left ventricular function and remodeling after the david v for significant aortic insufficiency.

BACKGROUND: Valve-sparing root replacement is controversial in patients with significant aortic insufficiency (AI) because the aortic valve cusps often require repair, which may potentially jeopardize long-term valve function. The purpose of this study was to evaluate valve function and left ventricular reverse remodeling in patients undergoing valve-sparing root replacement in the setting of significant AI. METHODS: A review of the Emory Aortic Surgery database between 2004 and 2012 identified 616 aortic root replacements. Of these procedures, 169 were performed for patients with 3+ or greater AI. Fifty-one patients (30%) underwent a David V procedure. Echocardiography was used to evaluate the degree of AI, left ventricular end-diastolic diameter, and left ventricular end-systolic diameter. RESULTS: The mean echocardiographic follow-up was 18 ± 21 months (range, 1 to 89). Patients undergoing valve-sparing root replacement had an increase in ejection fraction (preoperative 51% ± 7% versus postoperative 57% ± 6%, p < 0.01) and a reduction in left ventricular end-diastolic diameter (preoperative 58 ± 8 mm versus postoperative 48 ± 6 mm, p < 0.01) and left ventricular end-systolic diameter (preoperative 40 ± 8 mm versus postoperative 32 ± 6 mm, p < 0.01). During the follow-up period, freedom from greater than 1+ AI was 96%, and freedom from aortic valve replacement was 98%. The addition of cusp repair did not represent a significant risk factor for recurrent postoperative AI (p = 0.21). CONCLUSIONS: The David V technique produces significant left ventricular reverse remodeling and improved ventricular function in patients with chronic severe AI. Long-term data and close follow-up will be paramount in evaluating the durability of valve repair in this patient population.

Impact of varying degrees of renal dysfunction on transcatheter and surgical aortic valve replacement.

BACKGROUND: Renal impairment portends adverse outcomes in patients undergoing valvular heart surgery. The relationship between renal dysfunction in patients undergoing transcatheter aortic valve replacement (TAVR) is incompletely understood. METHODS: A retrospective review of 1336 patients undergoing surgical aortic valve replacement (SAVR; 2002-2012) and 321 patients undergoing TAVR (2007-2012) was performed. Patients were divided into 3 glomerular filtration rate (GFR) groups: GFR greater than 60 mL/min, GFR 31 to 60 mL/min, and GFR 30 mL/min or less. Logistic and linear regression analysis was performed to estimate the TAVR effect on outcomes. Risk adjustments were made using the Society for Thoracic Surgeons (STS) predicted risk of mortality (PROM). RESULTS: TAVR patients were older (82 vs 65 years; P < .001), had a poorer ejection fraction (48% vs 53%; P < .001), were more likely female (45% vs 41%; P = .23), and had a higher STS PROM (11.9% vs 4.6%; P < .001). In-hospital mortality rates for TAVR and SAVR were 3.5% and 4.1%, respectively (P = .60), a result that marginally favors TAVR after risk adjustment (adjusted odds ratio = .52, P = .06). In SAVR patients, worsening preoperative renal failure was associated with increased in-hospital mortality (P = .004) and hospital (P < .001) and intensive care unit (ICU) (P < .001) lengths of stay. In contrast, worsening renal function did not influence in-hospital mortality (P = .78) and hospital (P < .23) and ICU (P = .88) lengths of stay in TAVR patients. CONCLUSIONS: Worsening renal function was associated with increased in-hospital mortality, hospital length of stay, and ICU length of stay in SAVR patients, but not in TAVR patients. This unexpected finding may have important clinical implications in patients with aortic stenosis and preoperative renal dysfunction.

Acute type a dissection: impact of antegrade cerebral perfusion under moderate hypothermia.

BACKGROUND: The optimal method of arterial cannulation and circulation management for acute type A aortic dissection (type A) remains debated. Moderate hypothermic circulatory arrest (MHCA) and unilateral selective antegrade cerebral perfusion (uSACP) is effective in the elective setting. In this study, the impact of MHCA and uSACP on outcomes for type A repair was evaluated. METHODS: A retrospective review identified 346 patients who underwent type A repair under circulatory arrest, including 193 patients who had MHCA/uSACP. Measured outcomes included operative mortality, permanent neurologic deficit (PND) and temporary neurologic deficit, renal failure, and tracheostomy. Propensity-adjusted, multivariable logistic regression analysis was used to model adverse outcomes. RESULTS: The mean age of MHCA/uSACP patients was 56 years. The mean temperature during MHCA was 26.9 ± 2.0°C. Operative mortality for MHCA/SACP patients was 9.8% compared with 20.3% for the non-MHCA/SACP group (p < 0.01). Propensity score analysis found that MHCA/uSACP did not represent an adverse risk factor for mortality, temporary neurologic deficit, PND, renal failure, or the need for tracheostomy compared with non-MHCA/uSACP techniques. There was a 2.32-fold higher incidence of PND among patients who underwent cross-clamping of the dissected aorta during cooling before circulatory arrest (p < 0.05). CONCLUSIONS: Emergent type A repair can be accomplished with respectable operative risk using MHCA/uSACP. Cross-clamping the dissected aorta before MHCA increases the incidence of PND. These data suggest that MHCA/uSACP represents an effective circulation management strategy for patients undergoing repair of type A and obviates the need for deep hypothermic circulatory arrest.