Results of immediate surgical treatment of all acute type A dissections.

BACKGROUND: Surgery for acute type A aortic dissection is associated with a high mortality rate and incidence of postoperative complications. This study was designed to explore perioperative risk factors for death in patients with acute type A aortic dissection. METHODS AND RESULTS: One hundred twenty-four consecutive patients with acute type A aortic dissection between 1984 and 1998 were reviewed. All underwent operation with resection of the intimal tear and open distal anastomosis: 107 patients had surgery within 24 hours and 17 patients had surgery within 72 hours of symptom onset. Median age was 62 years (23 to 89); 89 were men. Forty-three patients had ascending aortic replacement only, 72 had hemiarch repair, in 2 the entire arch was replaced, and in 7 replacement included the proximal descending aorta. The aortic valve was replaced in 54 patients, resuspended in 52, and untouched in 18. Hospital mortality rate was 15.3% (19 of 124): of these, 3 patients died during surgery, 4 had fatal rupture of the distal aorta before discharge, and 2 died of malperfusion-related complications. Multivariate analysis revealed age >60, hemodynamic compromise, and absence of hypertension as preoperative indicators of hospital death (P:<0.05); the presence of new neurological symptoms was a significant preoperative risk factor in univariate analysis. Ominous intraoperative factors included contained hematoma and a comparatively low esophageal temperature but not cerebral ischemic time (mean 32 minutes). The site of the intimal tear did not influence outcome, but mortality rate was higher with more extensive resection: 43% with resection including the descending aorta died versus 14% with only ascending aorta or hemiarch replacement. Overall 5- and 10-year survival was 71% and 54%, respectively; among discharged patients (median follow-up 41 months) survival was 84% and 64% versus expected US survival of 92% and 79%. CONCLUSIONS: Immediate surgical treatment of all acute type A dissections with resection of the intimal tear and use of hypothermic circulatory arrest for distal anastomosis results in acceptable early mortality rates and excellent long-term survival.

Angiosarcoma of the left atrium mimicking myxoma: case report.

The case of a 65-year-old female patient with a pedunculated left atrial angiosarcoma is presented. Histologically, the tumor was composed of vascular spaces lined by atypical cells with similar cells in the solid portion of the tumor. Immunohistochemical stain for factor VIII-related antigen was positive in the cells forming vascular spaces. Immunoperoxidase stain for Ulex Europaeus I lectin was positive in cells lining vascular lumina and in individual cells in the solid portion of the tumor. Cardiac angiosarcomas characteristically occur in men, arise in the right atrium, are large mural masses that infiltrate widely at the time of presentation, and are usually rapidly fatal. Review of the literature reveals that this case of cardiac angiosarcoma is unusual by virtue of its occurrence in a female, left atrial location as a polypoid lesion, and prolonged symptom-free survival after surgical resection alone. Cardiac angiosarcoma may clinically and radiologically simulate myxoma.

Total correction of tetralogy of Fallot. How to deal with the complicated ascending aorta-right pulmonary artery anastomosis.

Ascending aorta-right pulmonary artery anastomosis may be complicated by deformity at the anastomotic site leading to discontinuity between pulmonary artery branches. Simple closure of such shunts through the ascending aorta is associated with residual stenosis and pressure gradients. An alternative approach which allows reconstruction of the entire intrapericardial pulmonary arterial system at the initial corrective operation is described. The transection of the ascending aorta facilitates the exposure necessary for this extensive repair. Two illustrative cases are presented.

Experience with profound hypothermia and circulatory arrest in the treatment of aneurysms of the aortic arch. Aortic arch replacement for acute arch dissections.

In a series of 21 consecutive patients, the aortic arch, varying portions of the ascending and descending aorta, and in some the aortic valve were replaced with the aid of a standard method of profound total body hypothermia and circulatory arrest. Fourteen patients underwent elective and seven patients emergency arch replacement. A combination of surface cooling and cardiopulmonary bypass was used to produce total body hypothermia. Replacement of the aortic arch was performed during a single period of circulatory arrest. Cardiopulmonary bypass was utilized for core rewarming. The average cerebral ischemic time was 37 +/- 14 minutes at an average core temperature of 13.7 degrees +/- 1.8 degrees C. The average myocardial ischemic time was 79 +/- 28 minutes with an average duration of cardiopulmonary bypass of 130 +/- 32 minutes. Of the 14 patients undergoing elective operation, three died; of the seven patients undergoing emergency operations, three died (two with ruptured aneurysms and one with acute arch dissection). Fifteen patients are alive and well 2 months to 7 years following the operation. All are free of neurologic sequelae. One has an asymptomatic residual dissection in the descending aorta. This experience indicates that profound total body hypothermia with circulatory arrest is a safe and effective method for elective surgical treatment of enlarging aneurysms of the aortic arch and for emergency treatment of acute dissections if the intimal tear is located in the aortic arch. The technique is simple and produces results superior to those reported for methods which involve selective cerebral perfusion during arch replacement.

Prolonged epicardial mapping in myocardial infarction: the effects of propranolol and intra-aortic balloon pumping following coronary artery occlusion.

A methods of prolonged epicardial surface mapping of myocardial infarction by serial epicardial ECG's is described. The progression of infarction following coronary artery ligation in dogs was monitored over a 4 day period and the early and late changes in the configuration of the epicardial ECG's associated with the underlying myocardial injury were defined. The determination of the infarct size by surface mapping in vivo correlated accurately with the final infarct size determined by dehydrogenase staining in vitro. Treatment with propranolol resulted in a significant reduction in the infarct size. Treatment with intra-aortic balloon pumping did not alter the size of the myocardial infarction induced in this experimental model.

Urgent operation for acute transverse aortic arch dissection.

Surgical intervention is generally accepted for acute type A dissection, but little is published regarding therapy for acute dissection of the transverse portion of the aortic arch, though involved in approximately 15% of cases. Often, surgical treatment is withheld if aortography suggests a primary tear in the aortic arch. Similarly, resection is limited to the ascending aorta despite intimal tears within the transverse portion of the arch. This work reports a 9-year experience with a policy of emergency resection for all acute aortic dissections involving the aortic arch. Intensive "antiimpulse" therapy is instituted and aortic angiograms are obtained. Type A dissections are resected under moderate hypothermia and, if the primary tear extends into the arch or is not found in the ascending aorta, the arch is explored during a brief period of deep hypothermia and circulatory arrest. If necessary, the arch is replaced during circulatory arrest, the patient's head is packed in ice, steroids are administered, and a barbiturate coma is induced. If arch replacement is anticipated preoperatively, surface cooling is also employed. Sixteen acute (up to 14 days) and three subacute (15 to 28 days) transverse arch dissections were treated in this manner between May 1979 and May 1988, with four (21%) hospital deaths (25%, acute; 0%, subacute). Mortality was related to left main coronary dissection with extensive myocardial infarction in two of our four cases, a third death was related to persistent seizures in a renal transplant patient requiring hemodialysis who had lupus cerebritis, and the fourth resulted from rupture of the descending aorta 15 days after arch replacement.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypothermic circulatory arrest in operations on the thoracic aorta. Determinants of operative mortality and neurologic outcome.

This study was undertaken to determine the factors that influence the final outcome after hypothermic circulatory arrest. Between 1985 and 1992 a uniform method of hypothermic circulatory arrest was used in 200 patients as the primary method of cerebral protection during operations on aneurysms of the thoracic aorta. There were 30 hospital deaths (15%). Age greater than 60 years (relative risk 3.7, p < 0.02), emergency operation and hemodynamic compromise (relative risk 22.2, p < 0.000), concomitant procedures (relative risk 2.7, p < 0.04), presentation with new neurologic symptoms (relative risk 5.2, p < 0.04), and postoperative permanent neurologic deficits (relative risk 9.4, p < 0.000) were found to be significant predictors of operative mortality. A total of 183 patients were available for evaluation of neurologic function and outcome. Multivariate analysis of this cohort of patients by multiple logistic regression showed that temporary neurologic dysfunction occurred in 36 cases (19%). Temporary neurologic dysfunction correlated with the duration of hypothermic circulatory arrest (47 +/- 16 minutes; odds ratio 1.06/minute; p < 0.001) and age (66 +/- 14 years; odds ratio 1.07/year; p < 0.001). Embolic strokes occurred in 22 patients (11%) and were associated with permanent deficits in 13 (7%). Strokes correlated significantly with age (older than 60, 21% versus younger than 60, 1%; p < 0.001) and operations on the arch and descending aortic aneurysms containing clot or atheroma (p < 0.001). This experience shows that the operative mortality is not affected by any parameters related to the use of hypothermic circulatory arrest. The incidence of temporary neurologic dysfunction rises linearly in relation to the age of the patient and the duration of hypothermic circulatory arrest. However, permanent neurologic injury is a result of thromboembolic events and is not related to the method of cerebral protection used. Additional methods to prevent perioperative embolic strokes are needed. Hypothermic circulatory arrest affords adequate cerebral protection if the arrest period is kept less than 60 minutes. We will continue to use this modality until the safety and utility of the alternate methods of cerebral protection are shown to be superior.

Repair of complex subvalvular aortic aneurysm with a valved conduit.

A subaortic annular aneurysm involving three fourths of the annular circumference was repaired with a valved conduit to which a Teflon felt flange was attached. This unique prosthetic repair assured a strong stable repair and uncompromised coronary flow otherwise unobtainable with previously described repairs.

Primary reconstruction of interrupted aortic arch by total aortic outflow obstruction.

Primary aortic arch reconstruction was undertaken in three neonates with interrupted aortic arch and ventricular septal defect. Total ascending aortic occlusion without cardiopulmonary bypass or profound hypothermia permitted, in each case, a rapid tension-free end-to-side descending-to-ascending aortic anastomosis without resulting neurologic or cardiac sequelae. This technique offers distinct advantages over previously described methods and should be considered whenever interrupted aortic arch is present with a ventricular septal defect.

Annular destruction in acute bacterial endocarditis. Surgical techniques to meet the challenge.

Destruction and disruption of ventricular-aortic or mitral-aortic continuity in the presence of acute infection of the annular tissue is a significant surgical challenge. Among 82 patients who underwent surgical treatment for acute endocarditis over a 10-year period, 15 (18.2%) had extensive destruction of the anulus necessitating special reconstructive techniques for treatment. Surgical treatment involved removal of all infected tissue including annular elements followed by appropriate restoration of the anulus for safe anchoring of the prosthetic valve. The reconstruction of the anulus consisted of the following: a Teflon felt patch inside and outside the aorta or ventricle, or both, for secure attachment of the prosthesis (felt aortic root, in three patients with native valve endocarditis), valved composite graft replacement of the aortic root for ventricular-aortic discontinuity (Bentall procedure, in eight patients with prosthetic valve endocarditis), composite patch reconstruction of the mitral anulus and the ascending aorta to restore mitral-aortic continuity (mitral-aortic composite patch in two patients with mitral-aortic prosthetic valve endocarditis), and direct suture of the sewing skirts of the mitral and aortic prostheses to restore the defect (attached skirts, in one patient with mitral-aortic native valve endocarditis). There was one hospital death caused by multiple organ failure. The most common complication was heart block. Two late deaths were due to reinfection resulting from continued intravenous drug abuse. One patient with a felt aortic root repair required late reoperation for subannular aneurysm. Eleven patients were followed up from 7 months to 66 months and are alive and well without complications. This experience indicates that these seemingly radical surgical techniques can be used in these desperately ill patients with safety and good long-term results. They offer the only lasting solution for major disruption in cardiac anatomy in the presence of infection.

Looking for the artery of Adamkiewicz: a quest to minimize paraplegia after operations for aneurysms of the descending thoracic and thoracoabdominal aorta.

All patients undergoing resection of thoracic or thoracoabdominal aneurysms at Mount Sinai Hospital since November 1993 had spinal cord function monitored with somatosensory-evoked potentials as part of a multimodality approach to reducing spinal cord injury. In the segment to be resected, each pair of intersegmental vessels was sequentially clamped, and they were subsequently sacrificed only if no change in somatosensory evoked potentials occurred within 8 to 10 minutes after occlusion. Adjunctive protective measures included mild hypothermia (31 degrees to 33 degrees C), distal perfusion, corticosteroids, maintenance of high normal blood pressures, avoidance of nitroprusside, and cerebrospinal fluid drainage. Ninety-five consecutive patients operated on since 1993 (group II) were compared with 138 earlier patients (group I). Preoperative characteristics such as age, sex, etiology of aneurysm, emergency operation, and reoperation did not differ between groups, nor did operative variables such as incidence of rupture and extent of resection. Group I had slightly more smokers and slightly fewer hypertensive individuals. Group II patients had a significantly better outcome with respect to in-hospital mortality (10.5% vs 18%, p = 0.045) and paraplegia (2% vs 8%, p = 0.008). By multivariate analysis, rupture and diabetes were associated with significantly higher in-hospital mortality, and smoking greatly increased the incidence of paraplegia. The extent of the aneurysm was a major determinant of mortality and paraplegia. The low paraplegia rate in group II was achieved without reattachment of a single intercostal or lumbar artery. No patient with fewer than 10 intersegmental arteries severed had paraplegia, and spinal cord ischemia was reversible in three patients after adjunctive maneuvers were performed to improve perfusion, suggesting that spinal cord blood supply is unlikely to depend on a single "artery of Adamkiewicz."

Neurologic outcome after ascending aorta-aortic arch operations: effect of brain protection technique in high-risk patients.

OBJECTIVE: We sought to assess the optimal strategy for avoiding neurologic injury after aortic operations requiring hypothermic circulatory arrest. METHODS: All 717 patients who survived ascending aorta-aortic arch operations through a median sternotomy since 1986 were examined for factors influencing stroke. Temporary neurologic dysfunction was assessed in all patients who survived the operation without stroke since 1993. Multivariate analyses were carried out to determine independent risk factors for neurologic injury. RESULTS: Independent risk factors for stroke were as follows: age greater than 60 years (P <.001; odds ratio, 4.5); emergency operation (P =.02; odds ratio, 2.2); new preoperative neurologic symptoms (P =.05; odds ratio, 2.9); presence of clot or atheroma (P <.001; odds ratio, 4.4); mitral valve replacement or other concomitant procedures (P =.055; odds ratio, = 3.7); and total cerebral protection time, defined as the sum of hypothermic circulatory arrest and any retrograde or antegrade cerebral perfusion (P =.001; odds ratio, 1.02/min). In 453 patients surviving operations without stroke after 1993, independent risk factors for temporary neurologic dysfunction included age (P <.001; odds ratio, 1.06/y), dissection (P =.001; odds ratio, 2.2), need for coronary artery bypass grafting (P =.006; odds ratio, 2.1) or other procedures (P =.023; odds ratio, 3.4), and total cerebral protection time (P <.001; odds ratio, 1.02/min). When all patients with total cerebral protection times between 40 and 80 minutes were examined, the method of cerebral protection did not influence the occurrence of stroke, but antegrade cerebral perfusion resulted in a significant reduction in incidence on temporary neurologic dysfunction (P =.05; odds ratio, 0.3). CONCLUSIONS: The occurrence of stroke is principally determined by patient- and disease-related factors, but use of antegrade cerebral perfusion can significantly reduce the occurrence of temporary neurologic dysfunction.

Neuropsychologic outcome after deep hypothermic circulatory arrest in adults.

INTRODUCTION: Pediatric patients undergoing prolonged periods of deep hypothermic circulatory arrest have been found to experience long-term deficits in cognitive function. However, there is limited information of this type in adult patients who are undergoing deep hypothermic circulatory arrest for thoracic aortic repairs. METHODS: One hundred forty-nine patients undergoing elective cardiac or thoracic aortic operations were evaluated preoperatively; 106 patients were evaluated early in the postoperative period (EARLY), and 77 patients were evaluated late in the postoperative period (LATE) with a battery of neuropsychologic tests. Seventy-three patients had routine cardiac operations without deep hypothermic circulatory arrest, and 76 patients with deep hypothermic circulatory arrest were divided into 2 subgroups: those with 1 to 24 minutes of deep hypothermic circulatory arrest (n = 36 patients) and those with 25 minutes or more of deep hypothermic circulatory arrest (n = 40 patients). The neuropsychologic test battery consisted of 8 tests encompassing 5 domains: attention, processing speed, memory, executive function, and fine motor function. Data were normalized to baseline values, and changes from baseline were analyzed by analysis of covariance, multivariate logistic regression, and survival functions. RESULTS: In all domains, poor performance or inability to be tested EARLY were significant predictors of poor performance LATE (odds ratio, 5.27; P <.01). Deep hypothermic circulatory arrest of 25 minutes or more and advanced age were significant predictors of poor performance LATE for the memory and fine motor domains. Deep hypothermic circulatory arrest of 25 minutes or more (odds ratio, 4. 0; P =.02) was a determinant of prolonged hospital stay (>21 days). CONCLUSION: Deep hypothermic circulatory arrest of 25 minutes or more and advanced age were associated with memory and fine motor deficits and with prolonged hospital stay.

Risk factors for rupture of chronic type B dissections.

OBJECTIVE: This study was an attempt to determine risk factors for rupture and to improve management of patients with type B aortic dissection who survive the acute phase without operation. METHODS: We studied 50 patients by means of serial computer-generated 3-dimensional computed tomographic scans. All patients who did not undergo operative treatment before the completion of at least 2 computed tomographic scans a minimum of 3 months apart after an acute type B dissection were included in the study. The median duration of follow-up was 40 months (range 0.9-112 months). Only 1 patient died of causes unrelated to the aneurysm during follow-up. Nine patients had fatal rupture (18%); 10 patients underwent elective aneurysm resection because of rapid expansion or development of symptoms, and 31 patients remained alive without operation or rupture. Possible risk factors for rupture in patients in the rupture, operative, and event-free groups were compared, as were dimensional data from first follow-up and last computed tomographic scans. RESULTS: Older age, chronic obstructive pulmonary disease, and elevated mean blood pressures were unequivocally associated with rupture (rupture versus event-free survival, P <.05), and pain was marginally significantly associated. Analysis of dimensional factors contributing to rupture was complicated by the fact that patients who underwent elective operation had significantly larger aneurysms and faster expansion rates than did either of the other groups, leaving comparisons of aneurysmal diameter between groups with and without rupture showing only marginal statistical significance. The last median descending aortic diameter before rupture in the rupture group was 5.4 cm (range 3.2-6. 7 cm). CONCLUSIONS: In an environment in which patients with large and rapidly expanding aneurysms are usually referred for surgical treatment, older patients with chronic type B dissections, especially if they have uncontrolled hypertension and a history of chronic obstructive pulmonary disease, are significantly more likely to have rupture than are younger, normotensive patients without lung disease. Neither the presence of a persistently patent false lumen nor a large abdominal aortic diameter appears to increase the risk of rupture. Overall, our nondimensional data strikingly resemble the natural history of patients with nondissecting aneurysms, suggesting that calculations derived from data on chronic descending thoracic and thoracoabdominal aneurysms would provide an overly conservative individual estimate of rupture risk for patients with chronic type B dissection, who tend toward earlier rupture of smaller aneurysms. A more aggressive surgical approach toward treatment of patients with chronic type B dissection seems warranted.

Left aortic arch and right descending aorta: diagnostic and therapeutic implications of a rare type of vascular ring.

A 3-month-old infant with acute airway obstruction due to the combination of left aortic arch and right descending aorta with persistence of a right ligamentum arteriosum is presented. This is a rare form of a vascular ring and carries special diagnostic and therapeutic implications. Guidelines for diagnosis and surgical treatment are outlined.

Retrograde cerebral perfusion as a method of neuroprotection during thoracic aortic surgery.

Retrograde cerebral perfusion is commonly used as an adjunct to hypothermic circulatory arrest to enhance cerebral protection during thoracic aortic surgery. This review summarizes a large number of studies that demonstrate a spectrum of beneficial, neutral, and detrimental effects of retrograde cerebral perfusion in humans and experimental animal models. It remains unclear whether retrograde cerebral perfusion provides effective cerebral perfusion, metabolic support, washout of embolic material, and improved neurological and neuropsychological outcome.

Experience with left ventricular apicoaortic conduits for complicated left ventricular outflow obstruction in children and young adults.

Six patients, ranging in age from 8 to 20 years, underwent left ventricular apicoaortic construction for treatment of complicated left ventricular outflow tract obstruction. All patients had severe left ventricular hypertrophy as determined by echocardiography and electrocardiography. The preoperative gradient across the left ventricular outflow tract was 84 +/- 17 mm Hg (mean +/- standard deviation) (range, 65 to 110 mm Hg), and the preoperative left ventricular end-diastolic pressure was 20 +/- 7 mm Hg (range, 12 to 28 mm Hg). Conduits were placed retroperitoneally with the distal anastomosis to the infrarenal aorta; the porcine valve was positioned in the left upper quadrant. Relief of left ventricular hypertension was complete; the minimal gradient measured intraoperatively was 13 +/- 8 mm Hg (range, 0 to 20 mm Hg). With an average follow-up of 18 months (range, 6 to 24 months), all patients have improved and are in Functional Class I. Four patients were catheterized 12 months postoperatively. They all showed excellent relief of left ventricular hypertension; the conduit was effectively decompressing the left ventricle. This experience suggests that this approach is effective in relieving complex left ventricular outflow tract obstruction with good early results, and that it deserves more frequent application in children.

Successful treatment of multiple simultaneous great vessel disruptions.

Survival following ruptures of the thoracic aorta at sites other than the aortic isthmus is exceedingly rare. Herein we describe a successful outcome in a 62-year-old woman with ascending and isthmic aortic lacerations compounded by disruptions of the subclavian-innominate artery junction and the left vertebral-subclavian junction. Chest wall instability and a myocardial contusion further complicated her case.

Cricothyroidotomy for prolonged ventilatory support after cardiac operations.

Forty-nine patients required prolonged ventilatory support after cardiac operations. Cricothyroidotomy was used routinely in these patients after approximately 7 days of endotracheal intubation. There were no infections of the median sternotomy wounds despite frequent colonization of the stoma. The only immediate complication was mild stomal bleeding in a patient taking anticoagulants. Nineteen patients (39%) died of underlying disease. The average duration of cricothyroidotomy was 59 days (range, 3 to 270 days). Cannulas were successfully removed in all survivors after an average of 38 days (range, 6 to 187 days). All of the patients were followed by personal interview, telephone contact, or contact with the referring physician. The average length of follow-up was 17 months (range, 2 to 50 months). All symptomatic patients were evaluated by laryngoscopy and bronchoscopy. One patient required endoscopic removal of granulation tissue from the stomal site; 2 others required tracheal resection for stenosis at the balloon site. There were no instances of subglottic stenosis. There were 4 late deaths, none of which was related to the cricothyroidotomy. Based on these findings, we suggest that cricothyroidotomy, with its low complication rate, is the procedure of choice for patients requiring prolonged mechanical ventilation after cardiac operations.

The protective effect of profound hypothermia on the canine central nervous system during one hour of circulatory arrest.

Circulatory arrest during profound hypothermia is a safe technique of cardiac surgery when used in selected instances. Despite its proven safety, the degree of cerebral protection offered by this technique is still poorly defined. Ten dogs anesthetized with Pentothal (thiopental sodium) were surface cooled to 32 degrees C. They were placed on cardiopulmonary bypass, cooled to 13 degrees C (cerebral temperature), and then underwent one hour of circulatory arrest. At the end of the arrest period, the dogs were rewarmed, resuscitated, and successfully weaned from bypass. A control group of 6 dogs were subjected to the same protocol but without the one-hour period of circulatory arrest. There were no group differences in animal weight, duration of surface cooling, cardiopulmonary bypass, or rewarming, mean flow, or mean arterial pressure. After a 7-day observation period, the dogs were killed with rapid tissue fixation using formalin. No neurological deficits were noted in any of the dogs during the observation period. The fixed brains were examined by a neuropathologist. No gross or microscopic evidence of cerebral hypoxia was seen in any of the animals. We conclude that one hour of circulatory arrest under profoundly hypothermic temperatures produces no detectable neurological changes or histological evidence of cerebral hypoxia.