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Loeys-Dietz syndrome presents early in life with rapidly progressive aortic aneurysmal disease, hypertelorism, and bifid uvula/cleft palate. Genetic testing reveals transforming growth factor-beta 1 and 2 mutations. Patients require monitoring for progressive aneurysmal disease, and may need total aortic replacement. Two patients are presented who typify these concepts.

Replacement of the aortic root with a prosthetic graft and valve in patients with Marfan's syndrome may prevent premature death from rupture of an aneurysm or aortic dissection. We reviewed the results of this surgical procedure at 10 experienced surgical centers.A total of 675 patients with Marfan's syndrome underwent replacement of the aortic root. Survival and morbidity-free survival curves were calculated, and risk factors were determined from a multivariable regression analysis.The 30-day mortality rate was 1.5 percent among the 455 patients who underwent elective repair, 2.6 percent among the 117 patients who underwent urgent repair (within 7 days after a surgical consultation), and 11.7 percent among the 103 patients who underwent emergency repair (within 24 hours after a surgical consultation). Of the 675 patients, 202 (30 percent) had aortic dissection involving the ascending aorta. Forty-six percent of the 158 adult patients with aortic dissection and a documented aortic diameter had an aneurysm with a diameter of 6.5 cm or less. There were 114 late deaths (more than 30 days after surgery); dissection or rupture of the residual aorta (22 patients) and arrhythmia (21 patients) were the principal causes of late death. The risk of death was greatest within the first 60 days after surgery, then rapidly decreased to a constant level by the end of the first year.Elective aortic-root replacement has a low operative mortality. In contrast, emergency repair, usually for acute aortic dissection, is associated with a much higher early mortality. Because nearly half the adult patients with aortic dissection had an aortic-root diameter of 6.5 cm or less at the time of operation, it may be prudent to undertake prophylactic repair of aortic aneurysms in patients with Marfan's syndrome when the diameter of the aorta is well below that size.

Objectives: Renal dysfunction occurring after cardiac operations has been attributed to various factors, but the importance of an atherosclerotic thoracic aorta has not been previously evaluated. The purpose of this study was to identify predictors of postoperative renal dysfunction (50% or more increase from preoperative values) and to evaluate the importance of atherosclerosis of the ascending aorta as a predictor of this complication. Methods: Nine hundred seventy-eight consecutive patients, 50 years of age and older with normal preoperative renal function (serum creatinine level of 1.5 mg/dL or less), who were scheduled to undergo cardiac surgery were prospectively evaluated. Atherosclerosis of the ascending aorta was assessed during the operation (with epiaortic ultrasound), and patients were divided into 3 groups according to its severity (normal-to-mild, moderate, and severe). Results: Univariate predictors of renal dysfunction at postoperative day 1 were atherosclerosis of the ascending aorta (P < .045) and postoperative low cardiac output (P = .05); at postoperative day 6 they were atherosclerosis of the ascending aorta (P < .0001), postoperative low cardiac output (P < .0001), advanced age (P = .001), decreased preoperative left ventricular function (P = .01), and female gender (P = .03). Multivariate analysis showed that atherosclerosis of the ascending aorta (odds ratio, 3.06; P = .04) was the only independent predictor of postoperative renal dysfunction at day 1 and that postoperative low cardiac output (odds ratio, 4.83; P < .0001), atherosclerosis of the ascending aorta (odds ratio, 2.13; P = .0006), and preoperative left ventricular dysfunction (odds ratio, 1.48; P = .028) were independent predictors of postoperative renal dysfunction at day 6. Conclusions: An atherosclerotic ascending aorta is an important predictor of postoperative renal dysfunction, possibly because atheroembolism to the kidneys occurs in the perioperative period (ie, during surgical manipulation of an atherosclerotic aorta) or because the diseased aorta may be a marker of widespread atherosclerotic disease that may predispose to perioperative renal dysfunction. (J Thorac Cardiovasc Surg 1999;117:111-6)

Background and Purpose After spinal cord ischemia, some neurons remain viable after an ischemic insult but may be at risk of dying during reperfusion. We searched for morphological and biochemical features of apoptosis, which is a mechanism of delayed neuronal death, in a rabbit model of spinal cord ischemia. Methods The infrarenal aorta of White New Zealand rabbits (n=24) was occluded for 40 minutes using a loop tourniquet. Rabbits were killed after 12, 24, or 48 hours (n=8 per group). The loop was placed but never tightened in sham-operated rabbits (n=6). The lumbar segment of the spinal cord (L5 to L7) was used for morphological studies, including hematoxylin and eosin staining and a modified terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end-labeling (TUNEL) staining method. Electron microscopy was used to examine ultrastructural morphology. In addition, lumbar tissue was used for biochemical investigation of DNA laddering by agarose gel electrophoresis. Results After ischemia, the affected areas contained neurons with positive TUNEL staining. Positive neurons were located in laminae III to IX, although most were concentrated in the intermediate and ventral areas. Adjacent sections stained with hematoxylin and eosin exhibited ischemic cell changes (red and ghost neurons), while apoptotic bodies were also apparent. In addition, electron microscopy of ischemic tissue samples exhibited ultrastructural characteristics of apoptosis, including nuclear condensation and relatively normal organelle morphology. Finally, isolated DNA revealed a ladder on agarose gel electrophoresis, indicating DNA fragmentation into ≈180 multiples of base pairs. Conclusions Spinal cord ischemia in rabbits induces morphological and biochemical changes suggestive of apoptosis. These data raise the possibility that apoptosis contributes to neuronal cell death after spinal cord ischemia.

Objective: We examined the characteristics of neuronal cell death after transient spinal cord ischemia in the rat and the effects of an N -methyl-d-aspartate antagonist, dextrorphan, and a protein synthesis inhibitor, cycloheximide. Methods: Spinal cord ischemia was induced for 15 minutes in Long-Evans rats with use of a 2F Fogarty catheter, which was passed through the left carotid artery and occluded the descending aorta, combined with a blood volume reduction distal to the occlusion. The rats were killed after 1, 2, and 7 days. Other groups of rats were pretreated with dextrorphan (30 mg/kg, intraperitoneally, n = 7), cycloheximide (30 mg, intrathecally, n = 7), or vehicle (saline solution, n = 12) and killed after 2 days. Results: This model reliably produced paraplegia and histopathologically distinct morphologic changes consistent with necrosis or apoptosis by light and electron microscopic criteria in different neuronal populations in the lumbar cord. Scattered necrotic neurons were seen in the intermediate gray matter (laminae 3 to 7) after 1, 2, and 7 days, whereas apoptotic neurons were seen in the dorsal horn laminae 1 to 3 after 1 and 2 days. Deoxyribonucleic acid extracted from lumbar cord showed internucleosomal fragmentation (laddering) on gel electrophoresis indicative of apoptosis. The severity of paraplegia in the rats treated with dextrorphan and cycloheximide was attenuated 1 day and 2 days after ischemia. The numbers of both necrotic and apoptotic neurons were markedly reduced in both dextrorphan- and cycloheximide-treated rats. Conclusions: The results suggest that both N -methyl-d-aspartate receptor-mediated excitotoxicity and apoptosis contribute to spinal cord neuronal death after ischemia and that pharmacologic treatments directed at blocking both of these processes may have therapeutic utility in reducing spinal cord ischemic injury. (J Thorac Cardiovasc Surg 1997;114:609-18)

Background. While extracardiac vascular disease (ECVD), defined as a history of peripheral vascular disease (PVD) or cerebrovascular disease (CBVD), is common in patients undergoing coronary artery bypass graft (CABG) surgery, there are limited data available on the association between ECVD, vein graft failure (VGF), and clinical outcomes. Methods. Using data from the Project of Ex-vivo Vein Graft Engineering via Transfection IV (PREVENTIV) trial (n [ 3,014), 1-year angiographic follow-up and 5year clinical outcomes (death, myocardial infarction, and revascularization) were determined in patients with and without ECVD. Logistic regression was used to assess risk of VGF. Generalized estimating equations methods were used to account for correlations in a graftlevel analysis. Kaplan-Meier estimates and Cox hazards regression were used to compare clinical outcomes. We similarly explored the association of the individual components CBVD and PVD with both VGF and clinical outcomes in an additive model. Results. Patients with ECVD (n [ 634, 21%) were older, more commonly female, and had more comorbidities, lower use of internal thoracic artery grafting, and overall worse graft quality than patients without ECVD. VGF rates tended to be higher (patient-level: odds ratio [OR]: 1.23, 95% confidence interval [CI] 0.96 to 1.58, p [ 0.099; graft-level: OR: 1.23, 95% CI: 1.00 to 1.53, p [ 0.053) in patients with ECVD. VGF rates were significantly higher among CBVD patients (OR: 1.42, 95% CI: 1.03 to 1.97, p [ 0.035; graft-level: OR: 1.40, 95% CI: 1.06 to 1.85, p [ 0.019). Patients with ECVD had a higher risk of death, myocardial infarction, or revascularization 5 years after CABG surgery (hazard ratio [HR]: 2.96, 95% CI: 2.02 to 4.35, p < 0.001). This relationship was driven by the subset of patients with PVD (HR [ 3.32, 95% CI: 2.16 to 5.09, p < 0.001) and not by those with CBVD (HR [ 1.10, 95% CI: 0.88 to 1.37, p [ 0.40). Conclusions. ECVD is common among patients undergoing CABG surgery and is associated with similar short-term but increasingly worse long-term clinical outcomes. This higher risk may be partly, but not exclusively, due to higher rates of VGF among these patients.

Objective To analyze clinical outcomes and distal segmental aortic growth and aortic reoperation rates following 1-stage open repair of extensive chronic aortic dissection that included resection and graft replacement of the aneurysmal descending thoracic aorta. Methods Among 68 patients undergoing extensive 1-stage repair of chronic aortic dissection that included the ascending aorta, arch, and varying lengths of the descending thoracic aorta, 66 were hospital survivors (early mortality 2.9%). Fifty-one of these patients (77%) had serial imaging studies suitable for calculation of growth rates of the remaining thoracic and upper abdominal aorta. The mean duration of follow-up was 5.8 years and extended to 13.7 years. Results The overall growth rate of the distal aorta for the entire cohort was 0.10 mm/year. For 28 patients followed for >5 years, the growth rate was 0.03 mm/year. Three patients required reoperation on the contiguous thoracic or abdominal aorta for aneurysmal degeneration 8 months, 34 months, and 6.2 years postoperatively. Actuarial freedom from reoperation for aneurysmal growth of the distal aorta at 5 and 10 years was 96.3% and 93.3%, respectively. Actuarial freedom from any aortic reoperation at 5 years and 10 years was 88.6% and 82.7%, respectively. Actuarial survival at 5, 7, and 10 years was 78.2%, 71.2%, and 57.3%, respectively. Conclusions Our extended experience with the 1-stage procedure confirms its safety and feasibility for treatment of extensive chronic thoracic aortic dissection. It is associated with a low incidence of reoperation on the contiguous aorta for aneurysmal degeneration. It represents a viable alternative to 2-stage and hybrid procedures that are also used to treat this condition.

Recognizing the importance of neuroprotection in aortic arch surgery, deep hypothermic circulatory arrest (DHCA) now underpins operative practice as it minimizes cerebral metabolic activity. When prolonged periods of circulatory arrest are required, selective antegrade cerebral perfusion (SACP) is supplemented as an adjunct. However, concerns exist over the risks of SACP in introducing embolism and hypo- and hyper-perfusing the brain. The present meta-analysis aims to compare postoperative outcomes in arch surgery using DHCA alone or DHCA + SACP as neuroprotection strategies.Electronic searches were performed using six databases from their inception to January 2013. Two reviewers independently identified all relevant studies comparing DHCA alone with DHCA + SACP. Data were extracted and meta-analyzed according to pre-defined clinical endpoints.Nine comparative studies were identified in the present meta-analysis, with 648 patients employing DHCA alone and 370 utilizing DHCA + SACP. No significant differences in temporary or permanent neurological outcomes were identified. DHCA + SACP was associated with significantly better survival outcomes (P=0.008, I(2)=0%), despite longer cardiopulmonary bypass time. Infrequent and inconsistent reporting of other clinical results precluded analysis of systemic outcomes.The present meta-analysis indicate the superiority of DHCA + SACP in terms of mortality outcomes.

A recent concern of deep hypothermic circulatory arrest (DHCA) in aortic arch surgery has been its potential association with increased risk of coagulopathy, elevated inflammatory response and end-organ dysfunction. Recently, moderate hypothermic circulatory arrest (MHCA) with selective antegrade circulatory arrest (SACP) seeks to negate potential hypothermia-related morbidities, while maintaining adequate neuroprotection. The present meta-analysis aims to compare postoperative outcomes in arch surgery using DHCA or MHCA+SACP as neuroprotective strategies.Electronic searches were performed using six databases from their inception to January 2013. Two reviewers independently identified all relevant studies comparing DHCA with MHCA+SACP, as defined by a recent hypothermia temperature consensus. Data were extracted and meta-analyzed according to pre-defined clinical endpoints.Nine comparative studies were identified for inclusion in the present meta-analysis. Stroke rates were significantly lower in patients undergoing MHCA+SACP (P=0.0007, I(2)=0%), while comparable results were observed with temporary neurological deficit, mortality, renal failure or bleeding. Infrequent and inconsistent reporting of systemic outcomes precluded analysis of other systemic outcomes.The present meta-analysis indicated the superiority of MHCA+SACP in terms of stroke risk.

Objectives. This study sought to determine the role of transesophageal echocardiography (TEE) and epiaortic ultrasound in the detection of atherosclerosis of the ascending aorta in patients undergoing cardiac surgery.Background. Atherosclerosis of the ascending aorta is a major risk factor for perioperative stroke and systemic embolism in patients undergoing cardiac surgery.Methods. Forty-four patients underwent prospective evaluation of the ascending aorta with two ultrasound techniques—epiaortic ultrasound and biplane TEE—and by palpation. The severity of atherosclerosis was graded on a four-point scale as normal, mild, moderate or severe.Results. A comparison of results with biplane TEE and those with epiaortic ultrasound yielded a kappa value of 0.12 (95% confidence interval 0 to 0.25), indicating poor correlation between the two. Compared with epiaortic ultrasound, biplane TEE significantly underestimated the severity of ascending aortic atherosclerosis, and this underestimation was more marked in the distal ascending aorta (p < 0.0001). When compared with epiaortic ultrasound and biplane TEE, palpation of the ascending aorta significantly underestimated the presence and severity of atherosclerosis (p < 0.0001 for both).Conclusions. Epiaortic ultrasound is more accurate than TEE for identification of atherosclerosis of the ascending aorta, but both ultrasound techniques are superior to palpation. Epiaortic ultrasound and TEE provide complementary information regarding thoracic aortic atherosclerosis. Modification of surgical technique on the basis of results of intraoperative epiaortic ultrasound and TEE in elderly patients undergoing cardiac procedures may prevent atheroembolic complications.

New volume requirements for coronary artery bypass grafting are being imposed on cardiac surgeons by hospitals, managed care groups, and others. The rationale for this is unclear. The available literature as well as additional sources relating volume and outcomes in cardiac surgery were extensively reviewed and reexamined. There are no data to conclusively indicate that outcomes of cardiac operations are related to a specific minimum number of cases performed annually by a cardiac surgeon. Each cardiothoracic surgeon should participate in a national database that permits comparison of his or her outcomes on a risk-adjusted basis with other surgeons. Until conclusive data become available that link volume to outcome, volume should not be used as a criterion for credentialing of cardiac surgeons by hospitals, managed care groups, or others. Instead, each surgeon should be evaluated on his or her individual results.

Many efforts to improve the quality of care focus on information drawn from databases. Such information can be very useful; however, the acquisition and analysis of data must be undertaken with caution. Six issues related to quality of care and the acquisition and analysis of data that pose problems for thoracic surgeons are the limitations and dangers of the right to know, the inadequacy of current databases, outcomes analysis and whether they help or hurt us, increased scrutiny of our practices, practice guidelines and the standards of care, and credentialing. To maximize the benefits of databases, physicians must participate in the process of data acquisition and analysis and the formulation of practice guidelines. Speaking out against the misuse of incomplete or inaccurate data and supporting Society initiatives that address these concerns will help us as we strive to maintain a strong physician-patient relationship and to deliver optimal care to our patients.

Background. Hypothermic cardiopulmonary bypass with intervals of circulatory arrest is a useful adjunct during operations on the descending thoracic aorta and distal aortic arch when severe aortic disease precludes placement of clamps on the aorta. Hypothermia also has a marked protective effect on spinal cord function during periods of aortic occlusion. Methods. Fifty-one patients (age range, 22 to 79 years) with descending thoracic or thoracoabdominal aortic disease had resection and graft replacement of the diseased aortic segments using hypothermic cardiopulmonary bypass and intervals of circulatory arrest in situations where the location, extent, or severity of disease precluded placement of clamps on the proximal aorta (8 patients) or (in 43 patients) when extensive thoracic (11) or thoracoabdominal (32) aortic disease was present and the risk for development of spinal cord ischemic injury and renal failure was judged to be increased. Patent intercostal (below T-6) and upper lumbar arteries were attached to the graft whenever possible. Results. Thirty-day mortality was 9.8% (5 patients). Paraplegia occurred in 2 and paraparesis in 1 of the 46 30-day survivors (6.5%). Among the 27 operative survivors with thoracoabdominal aneurysms, paraplegia occurred in 1 of 12 with Crawford type I (8%), 0 of 10 with type II, and 1 of 5 with type III aneurysms (20%). Paraplegia occurred in none of the 12 patients with aortic dissection and in 2 of the 15 patients with degenerative aneurysms. Renal failure requiring dialysis occurred in 1 (2.2%) of the 46 30-day survivors. Conclusions. Hypothermic circulatory arrest is a valuable adjunct for the treatment of complex aortic disease involving the aortic arch and thoracoabdominal aorta. In patients with thoracoabdominal aneurysms, its use has been associated with a low incidence of renal failure and an incidence of paraplegia/paraparesis in traditionally high-risk subsets (type I and II aneurysms, aortic dissection), which may be less than that observed with other surgical techniques.

Profound hypothermia induced with cardiopulmonary bypass has a protective effect on spinal cord function during operations on the thoracoabdominal aorta. The mechanism of this protection remains unknown. It has been proposed that the release of excitatory amino acids in the extracellular space plays a causal role in irreversible neuronal damage. We investigated the changes in extracellular neurotransmitter amino acid concentrations with the use of in vivo microdialysis in a swine model of spinal cord ischemia. All animals underwent left thoracotomy and right atrium-femoral artery cardiopulmonary bypass with additional aortic arch perfusion. Lumbar laminectomies were then done and microdialysis probes were inserted stereotactically in the anterior horn of the second and fourth segments of the lumbar spinal cord. The probes were perfused with artificial cerebrospinal fluid at a rate of 2 microliters/min and 15-minute samples were assayed by high-performance liquid chromatography. Group 1 animals (n = 6) underwent aortic clamping distal to the left subclavian artery and proximal to the renal arteries for 60 minutes at normothermia (37 degrees C) and group 2 animals (n = 5) were cooled to a rectal temperature of 20 degrees C before application of aortic clamps, maintained at this level during cardiopulmonary bypass until the aorta was unclamped, and then slowly rewarmed to 37 degrees C. Seven amino acids were studied, including two excitatory neurotransmitters (glutamate and aspartate) and five putative inhibitory neurotransmitters (glycine, gamma-aminobutyric acid, serine, adenosine, and taurine). Glutamate exhibited a threefold increase in extracellular concentration during normothermic ischemia compared with baseline values and remained elevated until 60 minutes after reperfusion. The increase in aspartate concentration was not significant. The extracellular concentrations of glycine and gamma-aminobutyric acid also increased significantly during ischemia and reperfusion. Hypothermia uniformly prevented the release of amino acids in the extracellular space. Glutamate levels remained significantly decreased even after rewarming to normothermia whereas glycine levels returned to baseline values. These results are consistent with a role for excitatory amino acids in the production of ischemic spinal cord injury and suggest that the mechanism of hypothermic protection may be related to decreased release of these amino acids in the ischemic spinal cord.

The Society of Thoracic Surgeons Clinical Practice Guidelines are intended to assist physicians and other health care providers in clinical decision making by describing a range of generally acceptable approaches for the diagnosis, management, or prevention of specific diseases or conditions. These guidelines should not be considered inclusive of all proper methods of care or exclusive of other methods of care reasonably directed at obtaining the same results. Moreover, these guidelines are subject to change over time, without notice. The ultimate judgment regarding the care of a particular patient must be made by the physician in light of the individual circumstances presented by the patient.

Guidelines for referral of chronic aortic insufficiency (AI) patients for aortic valve replacement (AVR) suggest that surgery can be delayed until symptoms or reduction in left ventricular (LV) contractile function occur. The frequent occurrence of reduced LV contractile function after AVR for chronic AI suggests that new contractile metrics for surgical referral are needed.In 16 chronic AI patients, cardiac MRI tagged images were analyzed before and 21.5 ± 13.8 months after AVR to calculate LV systolic strain. Average measurements of three strain parameters were obtained for each of 72 LV regions, normalized using a normal human strain database (n = 63), and combined into a composite index (multiparametric strain z score [MSZ]) representing standard deviation from the normal regional average.Preoperative global MSZ (72-region average) correlated with post-AVR global MSZ (R(2) = 0.825, p0.001). Preoperative global MSZ also predicts improvement of impaired regions (N = 271 regions from 14 AI patients, R(2) = 0.392, p0.001). Preoperative MRI-based LV ejection fraction (LVEF) is also predictive (r = 0.410, p0.001). Although global preoperative MSZ had a significantly higher correlation than preoperative LVEF with improvement of injured regions (p0.001), both measures convey the same phenomenon.Global preoperative MRI-based multiparametric strain predicts global strain postoperatively, as well as improvement of regions (n = 72 per LV) with impaired contractile function. Global contractile function is an important correlate with improvement in regionally impaired contractile function, perhaps reflecting total AI volume-overload burden (severity/duration of AI).

Objective Recent advances in endovascular surgery have put into question the role of open operative treatment of thoracoabdominal aortic aneurysms. In this context we evaluated our experience with thoracoabdominal aortic aneurysm repair using cardiopulmonary bypass and hypothermic circulatory arrest. Methods From January 1986 to December 2008, 218 patients (mean age, 63 ± 14 years) underwent thoracoabdominal aortic aneurysm repair with cardiopulmonary bypass and hypothermic circulatory arrest. The degree of repair was as follows: Crawford extent I, 57 (26%) patients; Crawford extent II, 91 (41%) patients; and Crawford extent III, 70 (32%) patients. Degenerative aneurysms were present in 160 (73%) patients. Eighteen (8%) patients underwent emergency operations. Results The mean durations of cardiopulmonary bypass and hypothermic circulatory arrest were 160 ± 44 and 31 ± 12 minutes, respectively. Stroke occurred in 8 (3.7%) patients, and spinal cord ischemic injury occurred in 10 (4.6%) patients (8 with paraplegia and 2 with paraparesis). Temporary dialysis for new-onset renal failure was required in 3.6% of hospital survivors. Thirty-day and 1-year mortality rates were 7.3% and 24.5%, respectively. After emergency operations, the 30-day mortality rate was 33.3% compared with 5.0% after elective operations ( P = .001). Five- and 10-year survivals were 55% and 23%, respectively. Twenty-five patients required reoperation on the graft or contiguous aorta at a mean of 5 ± 3 years after the initial procedure. Five- and 10-year rates of freedom from reoperation were 87% and 60%, respectively. Conclusions Cardiopulmonary bypass with hypothermic circulatory arrest can be safely used for thoracoabdominal aortic aneurysm repair, providing excellent protection against end-organ injury. Early mortality and morbidity rates do not exceed those reported for endovascular repair, with particularly favorable outcomes among patients undergoing elective operations.

The cause of cerebral and peripheral embolism remains undetermined in a significant number of patients. An atherosclerotic thoracic aorta has thus far been considered to be an uncommon one. To define the potential role of the ascending thoracic aorta as an embolic source, intraoperative ultrasonic aortic imaging was performed in 1200 of 1334 consecutive patients aged 50 years and older who were undergoing cardiac surgery. Patients were divided into two groups according to the results of the ultrasound study in terms of presence or absence of atherosclerotic disease. The prevalence of previous neurological events in the two groups was characterized and compared. Ascending aortic atherosclerosis was present in 231 (19.3%) of the patients studied. Patients in this category were older (P < .0001). A higher percentage of them were smokers (P < .0001) compared with patients with less severe disease. Coronary artery disease was more extensive (P = .012), and a higher percentage of these patients had a history of peripheral vascular disease (P < .0001). Univariate analysis of the subjects with (n = 158) and without (n = 1042) previous neurological events indicated that age, body mass index, atrial fibrillation, hypertension, and atherosclerosis of the ascending aorta were associated significantly with previous occurrence of a cerebrovascular accident. For the group as a whole, multiple logistic regression analysis demonstrated that hypertension (odds ratio, 1.81; P = .002), atherosclerosis of the ascending aorta (odds ratio, 1.65; P = .013), and atrial fibrillation (odds ratio, 1.54; P = .060) were significantly and independently associated with the occurrence of previous neurological events. Atherosclerosis of the ascending aorta is an independent risk factor for cerebrovascular events. An atherosclerotic ascending aorta may represent a potential source of emboli or may be a marker of generalized atherosclerosis.

Objective The authors evaluated the protective effect of hypothermic circulatory arrest for patients with bilateral carotid artery disease who underwent cardiac surgical procedures. Summary background data Severe bilateral carotid artery disease coexisting with cardiac disease that requires surgical treatment is associated with a substantial incidence of stroke after operations that require cardiopulmonary bypass. The optimal method of management of patients with these coexisting conditions is not established clearly. Because hypothermia has a protective effect on neural and myocardial tissue during cardiac operations, a protocol employing profound hypothermia and a period of circulatory arrest was evaluated in a group of patients who underwent combined carotid and cardiac surgery who were considered to be at increased risk for the development of stroke. Methods Fifty patients with bilateral carotid artery disease, including 24 patients with high-grade unilateral stenosis and contralateral occlusion and 6 patients with 80% to 99% bilateral stenosis, underwent combined carotid endarterectomy and cardiac surgery (coronary artery bypass grafting in all 50 patients and additional procedures in 8 patients). Profound systemic hypothermia (15 C) was instituted, and the carotid endarterectomy was performed during a period of circulatory arrest that averaged 30 minutes. The cardiac procedure was performed during the periods of cooling and rewarming. Results The 30-day mortality rate was 6% (3 patients). There were no early postoperative strokes or reversible ischemic neurologic deficits. There have been seven late deaths in the postoperative period, which extends to 54 months. None of these deaths were caused by stroke. There has been one late stroke, which occurred in the distribution of the unoperated carotid artery. Conclusions This technique provides adequate protection of the brain and myocardium during combined carotid and cardiac surgical procedures and appears to reduce the frequency of stroke in the high-risk subgroup of patients with bilateral carotid artery disease.

The optimal substitute for severely diseased aortic valves in children and young adults is unknown. The use of a mechanical prosthesis requires permanent treatment of the patient with anticoagulants and is associated with thromboembolic and hemorrhagic complications. Aortic-valve allografts and porcine bioprostheses, which do not necessitate anticoagulant therapy, may deteriorate and have limited durability.We therefore evaluated the use of the autologous pulmonary valve (i.e., the patient's own pulmonary valve) and the adjacent pulmonary artery as a replacement for the aortic valve and aortic sinuses in 33 patients. Five of the patients were from 8 to 16 years of age, and 28 were from 20 to 47 years of age. The pulmonary valve and the main pulmonary artery were used to replace the diseased aortic valve and the adjacent aorta. The coronary arteries were detached from the aorta and implanted into the pulmonary artery. The pulmonary valve and artery were replaced with a cryopreserved pulmonary allograft.There were no deaths during follow-up of up to 48 months (mean, 21 months). There were no episodes of infective endocarditis, and no reoperations on the aortic root were necessary. Also, there was no evidence on echocardiography of progressive dilatation of the autografts. With color-flow Doppler imaging, 22 patients were found to have only trivial regurgitation or none, 9 patients to have mild regurgitation, and no patients to have moderate or severe regurgitation across the autograft at the most recent follow-up visit. The mean peak velocity of flow across the autograft was 1.3 m per second (upper limit of normal, 1.8), indicating the absence of stenosis. One patient required reoperation for stenosis of the pulmonary allograft.Although the pulmonary-autograft procedure is more complex than simple aortic-valve replacement, it has been safely applied in selected patients, including young adults. Intermediate follow-up indicates satisfactory function of the autografts, with no dilatation or progressive valvular regurgitation. Pulmonary-root autografts may thus be the best available substitute for diseased aortic valves in children and young adults.

Spinal cord ischemia with resultant paraplegia or paraparesis remains an important clinical problem after operations on the thoracoabdominal aorta. Because hypothermia has a protective effect on ischemic neural tissue, we developed a baboon model of spinal cord ischemia to simulate the situation encountered clinically for resection of aneurysms of the thoracoabdominal aorta and to determine whether profound hypothermia produced by hypothermic cardiopulmonary bypass has a protective effect on spinal cord function. After cardiopulmonary bypass was established, the aorta was clamped distal to the left subclavian artery and proximal to the renal arteries for 60 minutes. Group I animals (n = 9) underwent aortic clamping at normothermia (37 degrees C), and group II animals (n = 9) were cooled to a rectal temperature of 15 degrees C before aortic clamping and underwent cardiopulmonary bypass at this temperature until the aorta was unclamped. Of the eight operative survivors in group I, six animals were paraplegic and two were paraparetic, whereas all six group II animals that survived the procedure were neurologically intact (p = 0.0002). The protective effect of hypothermia was associated with blunting of the hyperemic response of spinal cord blood flow (determined by the radioactive microsphere technique) in the lower thoracic and the lumbar segments of the spinal cord after unclamping of the aorta. Profound hypothermia produced by hypothermic cardiopulmonary bypass may be an effective method of protection of the spinal cord in patients undergoing repair of aneurysms of the thoracoabdominal aorta and may reduce the prevalence of ischemic injury to the spinal cord.

Atherosclerosis of the ascending aorta (AAA) and severe carotid artery disease are risk factors for stroke in cardiac surgical patients. Twelve hundred of a consecutive series of 1,334 patients 50 years of age or older having a cardiac operation were screened for the presence of AAA by intraoperative ultrasonographic scanning and for the presence of carotid artery occlusive disease (791 of 798 patients > or = 65 years of age and younger symptomatic patients) by carotid duplex scanning. Coronary artery disease was present in 88% of the patients. Patients with moderate or severe AAA (n = 231; 19.3% of the total) were treated by ascending aortic replacement (n = 27) or by modified, less extensive techniques (n = 168) to avoid the atherosclerotic areas. Thirty-three patients had combined carotid endarterectomy and cardiac operation. Thirty-day mortality and stroke rates for the 1,200 patients were 4.0% and 1.6%, respectively. The stroke rate was low (1.1%) among the 969 patients with no or mild AAA. It was zero among 27 patients with moderate or severe AAA who had ascending aortic replacement and among the 33 patients who had carotid endarterectomy. The stroke rates were higher for 111 patients with moderate or severe ascending aortic disease who had only minor interventions (6.3%) and for 16 patients with severe carotid artery disease who did not have carotid endarterectomy (18.7%). Screening for AAA and carotid artery disease and aggressive surgical treatment of moderate or severe AAA and severe or symptomatic carotid artery disease appears to reduce the frequency of stroke in older cardiac surgical patients.

The purpose of this study was to evaluate clinical outcomes of two different surgical techniques for the repair of acute type A dissection: open distal anastomosis under deep hypothermic circulatory arrest (DHCA) compared with distal aortic clamping on hypothermic cardiopulmonary bypass (ACPB). Between January 2000 and July 2008, 82 patients underwent DHCA and 42 had ACPB. Major morbidity, operative mortality and five-year actuarial survival were compared between groups. There were no significant differences in the preoperative characteristics. Operative mortality (17% in DHCA vs. 21% in ACPB, P=0.63), reoperation for bleeding (20% in DHCA vs. 34% in ACPB, P=0.16) and stroke rates (16 DHCA vs. 24% in ACPB, P=0.33) were comparable between the two groups. Actuarial five-year survival rates were 74% for DHCA vs. 73% for ACPB, P=0.99. No significant differences in operative mortality, major morbidity and actuarial five-year survival were observed between DHCA and ACPB. There are some practical technical advantages if the distal anastomosis is performed in an open manner. More studies are required to determine the fate of the false lumen between the two techniques.

Open surgical repair after failed endovascular aneurysm repair usually involves complete aneurysm removal and replacement with a prosthetic surgical graft. We describe an alternative strategy of open surgical repair of a thoracoabdominal aneurysm repair after failed endovascular aneurysm repair that entails preserving the functioning portion of the endograft and sewing the thoracoabdominal graft on the existing abdominal endograft.

[Figure][1] A 77-year-old woman underwent coronary artery bypass grafting in 2002. The surgeon noted a mass on the ascending aorta, adjacent to the innominate artery. He performed an off-pump coronary artery bypass grafting procedure to avoid manipulation of the aorta. The patient

Transesophageal echocardiography has been found to be an effective technique for the real-time assessment of myocardial and valvular function in postoperative patients. To determine the value of transesophageal echocardiography in patients with mechanical assist devices, we performed daily, bedside transesophageal echocardiography on 16 patients with right (n = 3), left (n = 1), or biventricular assist devices (n = 12). We obtained four-chamber and short-axis views in all patients. Valvular function and the presence of left-to-right shunts were evaluated by means of color flow Doppler imaging. During the echocardiographic study ventricular assist device flow was diminished to less than 1.5 L/min, and inotropic agents (dobutamine or epinephrine) were given to assess ventricular reserve. Changes in day-to-day ventricular function were assessed in comparisons made by two observers (one unaware of the study sequence) using a semiquantitative method for wall motion analysis. The left ventricular wall motion scores in the patients successfully weaned from left or biventricular assist devices (n = 5) improved (14.2 ± 1.6 versus 8.2 ± 1.5, p horac C ardiovasc S urg 1992;104:1410-6)

Background Current practice related to the management of atrial fibrillation (AF) complicating coronary artery bypass grafting (CABG) is uncertain. Methods We examined management of post-CABG AF in the PREVENT-IV trial, and we explored patterns of use of postoperative rhythm versus rate control and anticoagulation for AF by geographic region and type of site. We also compared outcomes of patients who developed post-CABG AF (663) with those who did not (2,131). Results The incidence of AF was 24%. Post-CABG AF was treated with a rhythm control strategy in 81% of patients and with warfarin in 23% of patients. Although there were significant variations across sites in the management of post-CABG AF, patterns of use of postoperative rhythm versus rate control and anticoagulation did not differ by geographic region or by whether or not the enrolling site was an academic institution. Mortality was higher in patients with post-CABG AF than patients without AF at 30 days (1.5% vs 0.7%, P = .01) but not at 3 years (6.9% vs 4.9%, P = .41). There was a trend toward a higher risk of mortality or stroke at 30 days in patients with AF (2.4% vs 1.9%, P = .08). Conclusion Although a rhythm control strategy was used in most of the patients in this trial and the overall rate of use of warfarin was low, the significance of these findings is uncertain because of the lack of data from randomized clinical trials. The substantial variations in the management of post-CABG AF across sites are likely because of definitive data on the most effective therapies, highlighting the need for clinical trials on rate versus rhythm control and on anticoagulation for AF in this setting.

During a 16-year interval ending in October 1990, 168 patients underwent 172 aortic root replacements. Thirty patients (18%) had Marfan syndrome. Annuloaortic ectasia (81 patients) and aortic dissection (63 patients) were the principal indications for operation. Twenty-seven patients (16%) had previous operations on the ascending aorta or aortic valve. The hospital mortality rate was 5% and the duration of cardiopulmonary bypass was the only significant independent predictor of early death (p = 0.017). Major modifications in technique were made in 1981, when the inclusion/wrap technique employing a composite graft (used in the first 105 procedures) was abandoned in favor of an open technique (used in 51 procedures), and in 1988, when aortic allografts and pulmonary autografts were introduced for selected conditions (reoperations, dissection, endocarditis, isolated aortic valve disease) in 16 patients. The mean duration of follow-up was 81 months. Forty-six patients were followed for more than 10 years. The actuarial survival rate was 61% at 7 years and 48% at 12 years. No significant difference in survival rate was observed between the patients with annuloaortic ectasia and aortic dissection, or between the inclusion/wrap and open techniques. However the frequency of pseudoaneurysm formation at suture lines and the frequency of reoperations on the ascending aorta and aortic valve were less with the open technique. The actuarial freedom from thromboembolism for the 152 patients with prosthetic valves was 82% at 12 years. One early and one late death occurred among the 16 patients with allograft or autograft root replacement. Anticoagulant therapy was not used in these patients and no thromboembolic episodes occurred in the follow-up period (mean, 7 months). The satisfactory results observed with extended follow-up support the continued use of the composite graft technique as the preferred method of treatment for patients with annuloaortic ectasia, persistent aneurysms of the sinuses of Valsalva following previous operations, and for patients with ascending aortic dissection who require aortic valve replacement. The availability of aortic root allografts and the perfection of techniques for safe implantation of the autologous pulmonary root into the aortic position have broadened the indications for aortic root replacement.

Diagnosis and treatment of thoracic vascular disease remain difficult problems for the clinician. These pathologic conditions often result in significant morbidity and mortality. Currently, published series document long-term treatment results and allow investigators to analyze both pre- and postoperative predictors of outcome. This review outlines some of the many significant publications over the past 12 months dealing with these disorders.

Although use of one internal mammary artery (IMA) for coronary artery bypass grafting does not appear to be associated with increased risk, the results with both IMAs are less certain; the potential for a higher incidence of sternal wound infection as a result of devascularization of the sternum is a major concern. During a 42-month interval ending July 1988, 1,566 patients had coronary artery bypass grafting alone or in combination with other procedures: 633 received only vein grafts, 687 had unilateral IMA grafting, and 246 had bilateral IMA grafting. The IMA patients were younger, were more often male, had better cardiac function, and underwent fewer emergent, urgent, or combined procedures than the patients receiving vein grafts (p less than 0.05). Thirty-day mortality was lower among the IMA patients (unilateral IMA group, 2.8%; bilateral IMA group, 3.7%; and vein graft group, 7.9%; p = 0.001). With the exception of sternal wound problems, occurrence rates for postoperative complications among the IMA patients did not differ significantly from or were lower (p less than 0.05) than those among the patients with vein grafts. Sternal infections occurred with greater frequency among the bilateral IMA patients (6.9%) than among the unilateral IMA (1.9%) or vein graft (1.3%) patients (p = 0.001). By univariate analysis, obesity, diabetes, bilateral IMA grafting, and need for prolonged (greater than 48 hours) mechanical ventilation were associated with a significantly higher incidence of sternal infection (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Between 43,000 and 47,000 people die annually in the United States from diseases of the aorta and its branches and continues to increase. For the thoracic aorta, these diseases are increasingly treated by stent-grafting. No prospective randomized study exists comparing stent-grafting and open surgical treatment, including for disease subgroups. Currently, one stent-graft device is approved by the Food and Drug Administration for descending thoracic aortic aneurysms although two new devices are expected to obtain FDA approval in 2008. Stent-graft devices are used "off label" or under physician Investigational Device Exemption studies for other indications such as traumatic rupture of the aorta and aortic dissection. Early first-generation devices suffered from problems such as stroke with insertion, ascending aortic dissection or aortic penetration from struts, vascular injury, graft collapse, endovascular leaks, graft material failure, continued aneurysm expansion or rupture, and migration or kinking; however, the newer iterations coming to market have been considerably improved. Although the devices have been tested in pulse duplicators out to 10 years, long-term durability is not known, particularly in young patients. The long-term consequences of repeated computed tomography scans for checking device integrity and positioning on the risk of irradiation-induced cancer remains of concern in young patients. This document (1) reviews the natural history of aortic disease, indications for repair, outcomes after conventional open surgery, currently available devices, and insights from outcomes of randomized studies using stent-grafts for abdominal aortic aneurysm surgery, the latter having been treated for a longer time by stent-grafts; and (2) offers suggestions for treatment.

To the Editor: We believe that transvascular and transapical implantation of cardiac valves is an important developing technology. In our opinion, however, the article “Percutaneous Implantation of the CoreValve Self-Expanding Valve Prosthesis in High-Risk Patients With Aortic Valve Disease: The Siegburg First-in-Man Study”1 inaccurately describes results of current therapy in order to favorably portray the 80% hospital survival with this device. The authors claim “up to 50%” operative mortality for surgical aortic valve replacement, citing 3 references. Reference 1 reports an overall mortality of 6%. Reference 2 reveals a mortality of 6% for aortic valve replacement in elderly patients. Reference 3 focuses on long-term survival. The Society of Thoracic …

Objective The purpose of the present study was to evaluate the early clinical outcomes of aortic root surgery in the United States. Methods The Society of Thoracic Surgeons database was queried to identify all patients who had undergone aortic root replacement from 2004 to early 2010 (n = 13,743). The median age was 58 years (range, 18-96); 3961 were women (29%) and 12,059 were white (88%). The different procedures included placement of a mechanical valve conduit (n = 4718, 34%), stented pericardial (n = 879, 6.4%) or porcine (n = 478, 3.5%) bioprosthesis, stentless root (n = 4309, 31%), homograft (n = 498, 3.6%), and valve sparing root replacement (n = 1918, 14%). Results The median number of aortic root surgeries per site was 2, and only 5% of sites performed >16 aortic root surgeries annually. An increased trend to use biostented (porcine or pericardial) valves during the study period (7% in 2004 vs 14% in 2009). The operative (raw) mortality was greater among the patients with aortic stenosis (6.2%) who had undergone aortic root replacement, independent of age. Mortality was greater in patients who had undergone concomitant valve or coronary artery bypass grafting or valve surgery (21%). The lowest operative mortality was observed in patients who had undergone aortic valve sparing procedures (1.9%). Conclusions Most cardiac centers performed aortic root surgery in small volumes. The unadjusted operative mortality was greater for patients >80 years old and those with aortic stenosis, regardless of age. Valve sparing root surgery was associated with the lowest mortality. A trend was seen toward an increased use of stented tissue valves from 2004 to 2009.

The optimal perfusion strategy during surgery of acute type A aortic dissection is controversial. The purpose of this study was to determine the impact of retrograde cerebral perfusion during hypothermic circulatory arrest on short-term and long-term outcome in this specific patient population.Between 1984 and 2005, 175 consecutive patients underwent repair of an acute type A dissection. Three different surgical approaches were used: aortic cross-clamping without hypothermic circulatory arrest in 50 (29%), hypothermic circulatory arrest alone in 69 (39%), and hypothermic circulatory arrest with supplemental retrograde cerebral perfusion in 56 (32%).Operative mortality was 18% +/- 3% (+/- 70% confidence interval), and adverse outcomes (death or cerebrovascular accident) occurred in 21% +/- 3% of patients (p = 0.97 between groups). Multivariate analysis identified valve replacement (p = 0.04), preoperative flow complications (p = 0.03), and non-Marfan syndrome (p = 0.04) as predictors of operative mortality. Intraoperative dissection (p0.001) and history of cerebrovascular disease (p = 0.02) were predictors for permanent neurologic deficit, and retrograde cerebral perfusion was shown to have a protective effect on transient neurologic deficits (p = 0.008). Kaplan-Meier survival was 75% +/- 3% at 1 year (131 patients at risk), 63% +/- 4% at 5 years (87 patients at risk), and 49% +/- 4% at 10 years (48 patients at risk) and was independent of surgical approach (p = 0.37). Long-term survival was diminished with increased age (p0.001), earlier operative year (p0.001), and coronary artery disease (p = 0.02).The current investigation suggests improved neurologic recovery with circulatory arrest and supplemental retrograde cerebral perfusion. Operative mortality and long-term survival were comparable among groups.

To the Editor: The comprehensive review of endovascular surgical techniques for repair of abdominal and thoracic aortic aneurysms by Katzen and colleagues1 provides important information on the current status and future directions of this new, less-invasive technology. In their discussion of the management of descending thoracic aortic aneurysms, the authors reported rates of postoperative paraplegia of …

Recent innovations in endovascular grafting technologyhave made the endovascular treatment of thoracic aorticaneurysm, dissection, and other thoracic aortic diseases aviable alternative to open surgical repair. Like many newsurgical procedures, thoracic endovascular stent-graftingpresents challenges to physicians who care for patientswith thoracic aortic disease. When new surgical proce-dures are introduced, the pressure for rapid adoption canlead to deviations from the fundamental principles ofphysician education and training and from the estab-lished indications for operative intervention. These devi-ations may compromise the quality and safety of patientcare.As with any surgical procedure, appropriate manage-ment of the specific underlying disease process involvesseveral distinct but interrelated components. First and fore-most, the involved physicians must possess a broad under-standing of the disease entity. Second, they must possessknowledge of, and expertise in, all of the available thera-peutic options, including, but not limited to, the new tech-nique that is being applied. They must be able to care forthe treated patients in the post-procedural period and todeal with the potential complications of a specific therapy.Third, they must receive technique-specific training. Toenable physicians to meet these basic requirements forthoracic endovascular grafting procedures and to becomecredentialed to perform them, specific criteria for all threeof these categories must be established.

To the Editor: In their prospective, multi-institutional study of adverse cerebral outcomes after coronary-artery bypass surgery, Roach et al. (Dec. 19 issue)1 have documented the frequency of such outcomes (6.1 percent) and their costs in terms of increases in mortality, length of hospital stay, and care after hospital discharge. It is becoming increasingly evident that atherosclerosis of the ascending aorta is one of the most important predictors, if not the most important predictor, of what the authors termed a type I outcome. Two studies, among others, have documented the importance of aortic atherosclerosis and the use of epiaortic ultrasonography or transesophageal echocardiography for its detection.2,3 Two studies involved over 1200 patients each,2,4 and one was prospective.2 These studies have established that visual inspection and palpation of the ascending aorta underestimate the frequency and severity of atherosclerosis.2,3