Judson B. Williams

Retrograde ascending aortic dissection as an early complication of thoracic endovascular aortic repair

OBJECTIVE Retrograde ascending aortic dissection (rAAD) is a potential complication of thoracic endovascular aortic repair (TEVAR), yet little data exist regarding its occurrence. This study examines the incidence, etiology, and outcome of this event. METHODS A prospective institutional database was used to identify cases of acute rAAD following TEVAR from a cohort of 309 consecutive procedures from March 2005 (date of initial Food and Drug Administration approval) to September 2010. The database was analyzed for the complication of rAAD as well as relevant patient and operative variables. RESULTS The incidence of rAAD was 1.9% (6/309); all cases occurred with proximal landing zone in the ascending aorta and/or arch (zones 0-2). All were identified in the perioperative period (range, 0-6 days) with 33% (2/6) 30-day/in-hospital mortality. Eighty-three percent (5/6) underwent emergent repair; one patient died without repair. rAAD patients were similar to the non-rAAD group (n = 303) across pertinent variables, including age, gender, race, and device size (all P > .1). rAAD incidence by aortic pathology was 1.0% (2/200) for aneurysm, 4.4% (4/91) for dissection, and 0% (0/18) for transection; P = .08. rAAD incidence by device was TAG (Gore) 1.0% (2/205), Talent (Medtronic) 4.7% (2/43), and Zenith TX2 (Cook) 3.6% (2/55). rAAD incidence was observed to be higher among patients with an ascending aortic diameter ≥ 4.0 cm (4.8% vs 0.9% for ascending diameter <4.0 cm); P = .047. Incidence was also higher with proximal landing zone in the native ascending aorta (zone 0) 6.9% (2/29) versus 1.4% for all others (4/280); P = .101. For patients with dissection pathology and an ascending aortic diameter ≥ 4.0 cm, 11% (3/28) suffered rAAD; with the combination of native ascending aorta (zone 0) landing zone measuring ≥ 4.0 cm, the incidence was 25% (2/8). Definitive diagnosis was by computed tomography angiography (n = 1), intraoperative transesophageal echocardiography (n = 3), intraoperative arteriography (n = 1), or postmortem autopsy (n = 1). CONCLUSIONS rAAD is a lethal early complication of TEVAR, which may be more common when treating dissection, with devices utilizing proximal bare springs or barbs for fixation, with native zone 0 proximal landing zone and with ascending aortic diameter ≥ 4 cm. Combinations of these risk factors may be particularly high risk. Intraoperative imaging assessment of the ascending aorta should be conducted following TEVAR to avoid under-recognition. National database reporting of this complication is needed to ensure safety and proper application of emerging TEVAR technology.

Contemporary results for proximal aortic replacement in North America.

OBJECTIVES The purpose of this study was to characterize operative outcomes for ascending aorta and arch replacement on a national scale and to develop risk models for mortality and major morbidity. BACKGROUND Contemporary outcomes for ascending aorta and arch replacement in North America are unknown. METHODS We queried the Society of Thoracic Surgeons Database for patients undergoing ascending aorta (with or without root) with or without arch replacement from 2004 to 2009. The database captured 45,894 cases, including 12,702 root, 22,048 supracoronary ascending alone, 6,786 ascending plus arch, and 4,358 root plus arch. Baseline characteristics and clinical outcomes were analyzed. A parsimonious multivariable logistic regression model was constructed to predict risks of mortality and major morbidity. RESULTS Operative mortality was 3.4% for elective cases and 15.4% for nonelective cases. A risk model for operative mortality (c-index 0.81) revealed a risk-adjusted odds ratio for death after emergent versus elective operation of 5.9 (95% confidence interval: 5.3 to 6.6). Among elective patients, end-stage renal disease and reoperative status were the strongest predictors of mortality (adjusted odds ratios: 4.0 [95% confidence interval: 2.6 to 6.4] and 2.3 (95% confidence interval: 1.9 to 2.7], respectively; p < 0.0001). CONCLUSIONS Current outcomes for ascending aorta and arch replacement in North America are excellent for elective repair; however, results deteriorate for nonelective status, suggesting that increased screening and/or lowering thresholds for elective intervention could potentially improve outcomes. The predictive models presented may serve clinicians in counseling patients.

Association Between Endoscopic vs Open Vein-Graft Harvesting and Mortality, Wound Complications, and Cardiovascular Events in Patients Undergoing CABG Surgery

CONTEXT The safety and durability of endoscopic vein graft harvest in coronary artery bypass graft (CABG) surgery has recently been called into question. OBJECTIVE To compare the long-term outcomes of endoscopic vs open vein-graft harvesting for Medicare patients undergoing CABG surgery in the United States. DESIGN, SETTING, AND PATIENTS An observational study of 235,394 Medicare patients undergoing isolated CABG surgery between 2003 and 2008 at 934 surgical centers participating in the Society of Thoracic Surgeons (STS) national database. The STS records were linked to Medicare files to allow longitudinal assessment (median 3-year follow-up) through December 31, 2008. MAIN OUTCOME MEASURES All-cause mortality. Secondary outcome measures included wound complications and the composite of death, myocardial infarction, and revascularization. RESULTS Based on Medicare Part B coding, 52% of patients received endoscopic vein-graft harvesting during CABG surgery. After propensity score adjustment for clinical characteristics, there were no significant differences between long-term mortality rates (13.2% [12,429 events] vs 13.4% [13,096 events]) and the composite of death, myocardial infarction, and revascularization (19.5% [18,419 events] vs 19.7% [19,232 events]). Time-to-event analysis for those patients receiving endoscopic vs open vein-graft harvesting revealed adjusted hazard ratios [HRs] of 1.00 (95% CI, 0.97-1.04) for mortality and 1.00 (95% CI, 0.98-1.05) for the composite outcome. Endoscopic vein-graft harvesting was associated with lower harvest site wound complications relative to open vein-graft harvesting (3.0% [3654/122,899 events] vs 3.6% [4047/112,495 events]; adjusted HR, 0.83; 95% CI, 0.77-0.89; P < .001). CONCLUSION Among patients undergoing CABG surgery, the use of endoscopic vein-graft harvesting compared with open vein-graft harvesting was not associated with increased mortality.

Relationship Between Vein Graft Failure and Subsequent Clinical Outcomes After Coronary Artery Bypass Surgery

Background— Vein graft failure (VGF) is common after coronary artery bypass graft surgery, but its relationship with long-term clinical outcomes is unknown. In this retrospective analysis, we examined the relationship between VGF, assessed by coronary angiography 12 to 18 months after coronary artery bypass graft surgery, and subsequent clinical outcomes. Methods and Results— Using the Project of Ex Vivo Vein Graft Engineering via Transfection IV (PREVENT IV) trial database, we studied data from 1829 patients who underwent coronary artery bypass graft surgery and had an angiogram performed up to 18 months after surgery. The main outcome measure was death, myocardial infarction, and repeat revascularization through 4 years after angiography. VGF occurred in 787 of 1829 patients (43%). Clinical follow-up was completed in 97% of patients with angiographic follow-up. The composite of death, myocardial infarction, or revascularization occurred more frequently among patients who had any VGF compared with those who had none (adjusted hazard ratio, 1.58; 95% confidence interval, 1.21–2.06; P=0.008). This was due mainly to more frequent revascularization with no differences in death (adjusted hazard ratio, 1.04; 95% confidence interval, 0.71–1.52; P=0.85) or death or myocardial infarction (adjusted hazard ratio, 1.08; 95% confidence interval, 0.77–1.53; P=0.65). Conclusions— VGF is common after coronary artery bypass graft surgery and is associated with repeat revascularization but not with death and/or myocardial infarction. Further investigations are needed to evaluate therapies and strategies for decreasing VGF to improve outcomes in patients undergoing coronary artery bypass graft surgery.

Midterm results with thoracic endovascular aortic repair for chronic type B aortic dissection with associated aneurysm.

OBJECTIVE Thoracic endovascular aortic repair for chronic type B aortic dissection with associated descending thoracic aneurysm remains controversial. Concerns include potential ischemic complications due to branch vessel origin from the chronic false lumen and continued retrograde false lumen/aneurysm sac pressurization via fenestrations distal to implanted endografts. The present study examines midterm results with thoracic endovascular aortic repair for chronic (>2 weeks) type B aortic dissection with associated aneurysm to better understand the potential role of thoracic endovascular aortic repair for this condition. METHODS Between March 2005 and December 2009, 51 thoracic endovascular aortic repair procedures were performed at a single institution for management of chronic type B dissection. The indication for thoracic endovascular aortic repair was aneurysm in all cases. A subset of 7 patients (14%) underwent placement of the EndoSure wireless pressure measurement system (CardioMEMS, Inc, Atlanta, Ga) in the false lumen adjacent to the primary tear for monitoring aneurysm sac/false lumen pulse pressure after thoracic endovascular aortic repair. RESULTS Mean patient age was 57±12 years (range, 30-82 years); 14 patients (28%) were female. Mean aortic diameter was 6.2±1.4 cm. There were no in-hospital/30-day deaths, strokes, or permanent paraplegia/paresis. There were no complications related to compromise of downstream branch vessels arising from the false lumen. Two patients (3.9%) who had preexisting ascending aortic dilation had retrograde acute type A aortic dissection; both were repaired successfully. Median postoperative length of stay was 4 days. Mean follow-up is 27.0±16.5 months (range, 2-60 months). Actuarial overall survival is 77.7% at 60 months with an actuarial aorta-specific survival of 98% over this same time period. Actuarial freedom from reintervention is 77.3% at 60 months. All patients with the EndoSure wireless pressure measurement system exhibited a decrease in aneurysm sac/false lumen pulse pressure indicating a depressurized false lumen. The aneurysm sac/false lumen pulse pressure ratio decreased from 52%±27% at the predischarge measurement to 14%±5% at the latest follow-up reading (P=.029). CONCLUSIONS Thoracic endovascular aortic repair for chronic type B dissection with associated aneurysm is safe and effective at midterm follow-up. Aneurysm sac/false lumen pulse pressure measurements demonstrate a significant reduction in false lumen endotension, thus ruling out clinically significant persistent retrograde false lumen perfusion and provide proof of concept for a thoracic endovascular aortic repair-based approach. Longer-term follow-up is needed to determine the durability of thoracic endovascular aortic repair for this aortic pathology.

Results with an algorithmic approach to hybrid repair of the aortic arch

OBJECTIVE Hybrid repair of the transverse aortic arch may allow for aortic arch repair with reduced morbidity in patients who are suboptimal candidates for conventional open surgery. We present our results with an algorithmic approach to hybrid arch repair, based on the extent of aortic disease and patient comorbidities. METHODS Between August 2005 and January 2012, 87 patients underwent hybrid arch repair by three principal procedures: zone 1 endograft coverage with extra-anatomic left carotid revascularization (zone 1; n = 19), zone 0 endograft coverage with aortic arch debranching (zone 0; n = 48), or total arch replacement with staged stented elephant trunk completion (stented elephant trunk; n = 20). RESULTS The mean patient age was 64 years, and the mean expected in-hospital mortality rate was 16.3% as calculated by the EuroSCORE II. Of operations, 22% (n = 19) were nonelective. Sternotomy, cardiopulmonary bypass, and deep hypothermic circulatory arrest were required in 78% (n = 68), 45% (n = 39), and 31% (n = 27) of patients to allow for total arch replacement, arch debranching, or other concomitant cardiac procedures, including ascending with or without hemiarch replacement in 17% (n = 8) of patients undergoing zone 0 repair. All stented elephant trunk procedures (n = 20) and 19% (n = 9) of zone 0 procedures were staged, with 41% (n = 12) of patients undergoing staged repair during a single hospitalization. The 30-day/in-hospital rates of stroke and permanent paraplegia or paraparesis were 4.6% (n = 4) and 1.2% (n = 1). Of 27 patients with native ascending aorta zone 0 proximal landing zone, three (11.1%) experienced retrograde type A dissection after endograft placement. The overall in-hospital mortality rate was 5.7% (n = 5); however, 30-day/in-hospital mortality increased to 14.9% (n = 13) owing to eight 30-day out-of-hospital deaths. Native ascending aorta zone 0 endograft placement was found to be the only univariate predictor of 30-day in-hospital mortality (odds ratio, 4.63; 95% confidence interval, 1.35-15.89; P = .02). Over a mean follow-up period of 28.5 ± 22.2 months, 13% (n = 11) of patients required reintervention for type 1A (n = 4), type 2 (n = 6), or type 3 (n = 1) endoleak. Kaplan-Meier estimates of survival at 1 year, 3 years, and 5 years were 73%, 60%, and 51%. CONCLUSIONS Hybrid aortic arch repair can be tailored to patient anatomy and comorbid status to allow complete repair of aortic pathology, frequently in a single stage, with acceptable outcomes. However, endograft placement in the native ascending aorta is associated with high rates of retrograde type A dissection and 30-day/in-hospital mortality and should be approached with caution.

Secondary Prevention After Coronary Artery Bypass Graft Surgery Findings of a National Randomized Controlled Trial and Sustained Society-Led Incorporation Into Practice

Background— Despite evidence supporting the use of aspirin, β-blockers, angiotensin-converting enzyme inhibitors, and lipid-lowering therapies in eligible patients, adoption of these secondary prevention measures after coronary artery bypass grafting has been inconsistent. We sought to rigorously test on a national scale whether low-intensity continuous quality improvement interventions can be used to speed secondary prevention adherence after coronary artery bypass grafting. Methods and Results— A total of 458 hospitals participating in the Society of Thoracic Surgeons National Cardiac Database and treating 361 328 patients undergoing isolated coronary artery bypass grafting were randomized to either a control or an intervention group. The intervention group received continuous quality improvement materials designed to influence the prescription of the secondary prevention medications at discharge. The primary outcome measure was discharge prescription rates of the targeted secondary prevention medications at intervention versus control sites, assessed by measuring preintervention and postintervention site differences. Prerandomization treatment patterns and baseline data were similar in the control (n=234) and treatment (n=224) groups. Individual medication use and composite adherence increased over 24 months in both groups, with a markedly more rapid rate of adherence uptake among the intervention hospitals and a statistically significant therapy hazard ratio in the intervention versus control group for all 4 secondary prevention medications. Conclusions— Provider-led, low-intensity continuous quality improvement efforts can improve the adoption of care processes into national practice within the context of a medical specialty society infrastructure. The findings of the present trial have led to the incorporation of study outcome metrics into a medical society rating system for ongoing quality improvement. # Clinical Perspective {#article-title-27}Background— Despite evidence supporting the use of aspirin, &bgr;-blockers, angiotensin-converting enzyme inhibitors, and lipid-lowering therapies in eligible patients, adoption of these secondary prevention measures after coronary artery bypass grafting has been inconsistent. We sought to rigorously test on a national scale whether low-intensity continuous quality improvement interventions can be used to speed secondary prevention adherence after coronary artery bypass grafting. Methods and Results— A total of 458 hospitals participating in the Society of Thoracic Surgeons National Cardiac Database and treating 361 328 patients undergoing isolated coronary artery bypass grafting were randomized to either a control or an intervention group. The intervention group received continuous quality improvement materials designed to influence the prescription of the secondary prevention medications at discharge. The primary outcome measure was discharge prescription rates of the targeted secondary prevention medications at intervention versus control sites, assessed by measuring preintervention and postintervention site differences. Prerandomization treatment patterns and baseline data were similar in the control (n=234) and treatment (n=224) groups. Individual medication use and composite adherence increased over 24 months in both groups, with a markedly more rapid rate of adherence uptake among the intervention hospitals and a statistically significant therapy hazard ratio in the intervention versus control group for all 4 secondary prevention medications. Conclusions— Provider-led, low-intensity continuous quality improvement efforts can improve the adoption of care processes into national practice within the context of a medical specialty society infrastructure. The findings of the present trial have led to the incorporation of study outcome metrics into a medical society rating system for ongoing quality improvement.

Long-Term Survival of Patients With Ischemic Cardiomyopathy Treated by Coronary Artery Bypass Grafting Versus Medical Therapy

BACKGROUND We prospectively applied the Surgical Treatment of Ischemic Cardiomyopathy trial entry criteria to an observational database to determine whether coronary artery bypass grafting (CABG) decreases mortality compared with medical therapy (MED) for patients with coronary artery disease and depressed left ventricular ejection fraction. METHODS This was a retrospective, observational, cohort study of prospectively collected data from the Duke Databank for Cardiovascular Disease. Long-term mortality was the main outcome measure. Between January 1, 1995, and July 31, 2009, 86,874 patients underwent cardiac catheterization for suspected ischemic heart disease and were evaluated for inclusion in the analysis. RESULTS A total of 2,624 patients were found to have left ventricular ejection fraction less than 0.35, coronary artery disease amenable to CABG, and no left main stenosis of greater than 50%. After exclusions including ongoing Canadian Cardiovascular Society class III angina and acute myocardial infarction, 763 patients were included for propensity score analysis, including 624 who received MED and 139 who underwent CABG. Adjusted mortality curves were constructed for those patients in the three quintiles most likely to receive CABG. The curves diverged early, with risk-adjusted mortality rates at 5 years of 46% for MED versus 29% for CABG, and the survival benefit of CABG over MED continued through 10 years of follow-up (hazard ratio, 0.63; 95% confidence interval, 0.45 to 0.88). CONCLUSIONS Among a propensity-matched, risk-adjusted, observational cohort of patients with coronary artery disease, left ventricular ejection fraction less than 0.35, and no left main disease of greater than 50%, CABG is associated with a survival advantage over MED through 10 years of follow-up.

Staged total abdominal debranching and thoracic endovascular aortic repair for thoracoabdominal aneurysm

OBJECTIVE Thoracoabdominal aortic aneurysms (TAAAs) occur most commonly in elderly individuals, who are often suboptimal candidates for open repair because of significant comorbidities. The availability of a hybrid option, including open visceral debranching with endovascular aneurysm exclusion, may have advantages in these patients who are at high-risk for conventional repair. This report details the evolution of our technique and results with complete visceral debranching and endovascular aneurysm exclusion for TAAA repair in high-risk patients. METHODS Between March 2005 and June 2011, 47 patients (51% women) underwent extra-anatomic debranching of all visceral vessels, followed by aneurysm exclusion by endovascular means at a single institution. A median of four visceral vessels were bypassed. The debranching procedure was initially performed through a partial right medial visceral rotation approach, leaving the left kidney posterior in the first 22 patients, and in the last 25 by a direct anterior approach to the visceral vessels. The debranching and endovascular portions of the procedure were performed in a single operation in the initial 33 patients and as a staged procedure during a single hospital stay in the most recent 14. RESULTS Median patient age was 71.0 ± 9.8 years. All had significant comorbidity and were considered suboptimal candidates for conventional repair: 55% had undergone previous aortic surgery, 40% were American Society of Anesthesiologists (ASA) class 4, and baseline serum creatinine was 1.5 ± 1.3 mg/dL. The 30-day/in-hospital rates of death, stroke, and permanent paraparesis/plegia were 8.5%, 0%, and 4.3%, respectively, but 0% in the most recent 14 patients undergoing staged repair. These patients had significantly shorter combined operative times (314 vs 373 minutes), decreased intraoperative red blood cell transfusions (350 vs 1400 mL), and were more likely to be extubated in the operating room (50% vs 12%) compared with patients undergoing simultaneous repair. Over a median follow-up of 19.3 ± 18.5 months, visceral graft patency was 97%; all occluded limbs were to renal vessels and clinically silent. There have been no type I or III endoleaks or reinterventions. Kaplan-Meier overall survival is 70.7% at 2 years and 57.9% at 5 years. CONCLUSIONS Hybrid TAAA repair through complete visceral debranching and endovascular aneurysm exclusion is a good option for elderly high-risk patients less suited to conventional repair in centers with the requisite surgical expertise with visceral revascularization. A staged approach to debranching and endovascular aneurysm exclusion during a single hospitalization appears to yield optimal results.

Outcomes of Acute Type A Dissection Repair Before and After Implementation of a Multidisciplinary Thoracic Aortic Surgery Program

OBJECTIVES The purpose of this study was to compare the results of acute type A aortic dissection (ATAAD) repair before and after implementation of a multidisciplinary thoracic aortic surgery program (TASP) at our institution, with dedicated high-volume thoracic aortic surgeons, a multidisciplinary approach to thoracic aortic disease management, and a standardized protocol for ATAAD repair. BACKGROUND Outcomes of ATAAD repair may be improved when operations are performed at specialized high-volume thoracic aortic surgical centers. METHODS Between 1999 and 2011, 128 patients underwent ATAAD repair at our institution. Records of patients who underwent ATAAD repair 6 years before (n = 56) and 6 years after (n = 72) implementation of the TASP were retrospectively compared. Expected operative mortality rates were calculated using the International Registry of Acute Aortic Dissection pre-operative prediction model. RESULTS Baseline risk profiles and expected operative mortality rates were comparable between patients who underwent surgery before and after implementation of the TASP. Operative mortality before TASP implementation was 33.9% and was statistically equivalent to the expected operative mortality rate of 26.0% (observed-to-expected mortality ratio 1.30; p = 0.54). Operative mortality after TASP implementation fell to 2.8% and was statistically improved compared with the expected operative mortality rate of 18.2% (observed-to-expected mortality ratio 0.15; p = 0.005). Differences in survival persisted over long-term follow-up, with 5-year survival rates of 85% observed for TASP patients compared with 55% for pre-TASP patients (p = 0.002). CONCLUSIONS ATAAD repair can be performed with results approximating those of elective proximal aortic surgery when operations are performed by a high-volume multidisciplinary thoracic aortic surgery team. Efforts to standardize or centralize care of patients undergoing ATAAD are warranted.