Aortic dissection: a medical perspective

[Acute aortic syndromes and sleep apnea]

Obstructive sleep apnea (OSA) is a common disease, often present in "cardiovascular or metabolic patients". OSA favours the occurrence of arterial lesions, all the more if severe. There is a strong relationship between OSA and acute aortic syndromes (AAS). This relationship is in part explained by aortic dilatation linked to OSA. The presence of repeated episodes of sudden variation of transmural pressure applied on aortic wall seems to play a major role in this dilatation. All OSA patients should have a search of aortic dilatation by ultrasound (at a thoracic and abdominal level). Also, screening of OSA should be systematically performed in patients with aortic disease. The effect of continuous positive airway pressure in apneic patients with AAS has not been studied.

Conservative management of chronic aortic dissection with underlying aortic aneurysm

Aortic dissection is one of the most common aortic emergencies affecting around 2000 Americans each year. It usually presents in the acute state but in a small percentage of patients aortic dissections go unnoticed and these patients survive without any adequate therapy. With recent advances in medical care and diagnostic technologies, aortic dissection can be successfully managed through surgical or medical options, consequently increasing the related survival rate. However, little is known about the optimal long-term management of patients suffering from chronic aortic dissection. The purpose of the present report is to review aortic dissection, namely its pathology and the current diagnostic tools available, and to discuss the management options for chronic aortic dissection. We report a patient in which chronic aortic dissection presented with recurring episodes of vomiting and also discuss the management plan of our patient who had a chronic aortic dissection as well as an underlying aortic aneurysm.

[Aortic dissection spread to the renal arteries: role of renal volumetry after angioplasty]

OBJECTIVE

Type A or B aortic dissection can extend to renal arteries, causing a renal ischemia which treatment is usually endovascular. The aim of our study is to show the interest of the renal volumetry in the follow-up of these patients.

PATIENTS AND METHODS

Twenty-two patients (16 men, mean age 63.4±11.8years, BMI 25.2±3.4kg/m(2)) with a type A or B aortic dissection spread to one or to both renal arteries and followed at Grenoble university hospital were consecutively included. All patients underwent renal angiography with aorto-renal pressure gradients measurements and follow-up by renal volumetry (scanner Siemens(®)). A renal ischemia was defined by a decrease of 20% or more of the volumetry.

RESULTS

Sixteen patients (73%) were hypertensive before the aortic dissection among which ten (62%) were treated. Eight patients (36%) have a significant renal pressure gradient among which five (62%) underwent renal endovascular therapy. The renal volumetry of these five patients remained unchanged while six of 17 patients (36%) without angioplasty have a decreasing volumetry.

CONCLUSION

Renal volumetry appeared an effective and attractive option for the follow-up of the patients with aortic dissection spread to the renal arteries. These results should be taken into account to put the indication of an endovascular treatment.

A three-layer model for buckling of a human aortic segment under specific flow-pressure conditions

Human aortas are subjected to large mechanical stresses because of blood flow pressurization and through contact with the surrounding tissue. It is essential that the aorta does not lose stability by buckling with deformation of the cross-section (shell-like buckling) (i) for its proper functioning to ensure blood flow and (ii) to avoid high stresses in the aortic wall. A numerical bifurcation analysis employs a refined reduced-order model to investigate the stability of a straight aorta segment conveying blood flow. The structural model assumes a nonlinear cylindrical orthotropic laminated composite shell composed of three layers representing the tunica intima, media and adventitia. Residual stresses because of pressurization are evaluated and included in the model. The fluid is formulated using a hybrid model that contains the unsteady effects obtained from linear potential flow theory and the steady viscous effects obtained from the time-averaged Navier-Stokes equations. The aortic segment loses stability by divergence with deformation of the cross-section at a critical flow velocity for a given static pressure, exhibiting a strong subcritical behaviour with partial or total collapse of the inner wall. Preliminary results suggest directions for further study in relation to the appearance and growth of dissection in the aorta.

Predictors of poor blood pressure control assessed by 24 hour monitoring in patients with type B acute aortic dissection

The chronic management of post-acute aortic dissection (AD) of the descending aorta (Type B) is based on optimal control of blood pressure (BP), with a target BP < 135/80 mmHg. The aim of our study was to determine and verify effective blood pressure control with an objective measurement method and to identify predicting factors.

Standard of practice for the endovascular treatment of thoracic aortic aneurysms and type B dissections

Thoracic endovascular aortic repair (TEVAR) represents a minimally invasive technique alternative to conventional open surgical reconstruction for the treatment of thoracic aortic pathologies. Rapid advances in endovascular technology and procedural breakthroughs have contributed to a dramatic transformation of the entire field of thoracic aortic surgery. TEVAR procedures can be challenging and, at times, extraordinarily difficult. They require seasoned endovascular experience and refined skills. Of all endovascular procedures, meticulous assessment of anatomy and preoperative procedure planning are absolutely paramount to produce optimal outcomes. These guidelines are intended for use in quality-improvement programs that assess the standard of care expected from all physicians who perform TEVAR procedures.

Standard of practice for the endovascular treatment of thoracic aortic aneurysms and type B dissections

Thoracic endovascular aortic repair (TEVAR) represents a minimally invasive technique alternative to conventional open surgical reconstruction for the treatment of thoracic aortic pathologies. Rapid advances in endovascular technology and procedural breakthroughs have contributed to a dramatic transformation of the entire field of thoracic aortic surgery. TEVAR procedures can be challenging and, at times, extraordinarily difficult. They require seasoned endovascular experience and refined skills. Of all endovascular procedures, meticulous assessment of anatomy and preoperative procedure planning are absolutely paramount to produce optimal outcomes. These guidelines are intended for use in quality-improvement programs that assess the standard of care expected from all physicians who perform TEVAR procedures.

Epidemiology and Long-Term Prognostic Factors in Acute Type B Aortic Dissection

The epidemiological data and reports on long-term predictors of mortality after medically or endovascularly and medically treated patients with acute type B aortic dissection (AD) are scarce. Patients with type B AD between 2000 and 2004 were identified through the inpatient endovascular or autopsy registry at Malmö-Lund University Hospital, Sweden. Seventy-two patients had acute type B AD, of whom eight were found at autopsy. Shock due to ruptured type B AD was associated with in-hospital mortality (P = 0.006) in the 64 eligible patients. Renal insufficiency (odds ratio [OR] = 4.7, 95% confidence interval [CI] 1.1-19.4) and coexistent aortic disease (OR = 4.1, 95% CI 1.0-16.9) remained as independent predictors for long-term mortality after multivariate logistic regression analysis. Endovascular intervention (n = 32) was associated with neither short- nor long-term mortality. The estimated overall incidence of acute type B AD was 2.1/100,000 person-years, and the highest incidence rates were found in men aged 65-74 years (14.6/100,000 person-years) and women aged 75-84 years (19.0/100,000 person-years). Survival in patients with complicated acute type B AD managed with the endovascular technique was the same as in uncomplicated medically treated patients. Renal insufficiency and coexistent aortic disease were strong predictors for long-term mortality.

Dissection of the temporal artery in a patient with giant cell arteritis

A 74-year-old woman presented to her rheumatologist with classic symptoms of giant cell arteritis. The temporal arteries were strikingly swollen, warm, and erythematous. On biopsy of the right temporal artery, a focal dissection was found associated with a pan-arteritis and giant cells. Isolated temporal artery dissection in giant cell arteritis has not been reported previously. We propose that the unusually intense vascular inflammation may have weakened the vessel wall, so that the dissection occurred during the routine physical exam or biopsy. We believe this case illustrates that physicians should take special care in the examination of floridly inflamed vessels, because vigorous palpation might lead to dissection. In the case of patients with giant cell arteritis, dissection may result in an increased risk of ischemic complications, such as scalp necrosis.

Endovascular stent-grafts treatment in acute aortic dissection (type B): Clinical outcomes during early, late, or chronic phases

OBJECTIVE

This is a prospective study to evaluate the clinical outcomes of endovascular repair in patients with different phases of type B aortic dissection.

BACKGROUND

Endovascular repairing with stent-grafts is an innovative technique for type B acute aortic dissection. There is no previous study regarding outcomes in different time phases.

METHODS

Sixty-two patients underwent endovascular stent-grafts. There were 23 in the early phase (<24 hr), 20 in the late phase (>or=24 hr to 2 weeks), and 19 in the chronic phase (>2 weeks).

RESULTS

The early phase group had the lowest ratio of stent-grafts to patient and the shortest stent-graft length. The chronic phase group had the largest diameter of false lumen. The technical success rate was 100%; no patient died within hospital. Three patients died within 30 days, with the same death rate in every group. Compared with acute patients, the chronic group had a higher volume of contrast, a higher creatinine post-procedure, and a higher incidence of contrast-induced nephropathy. Multiple regression analysis demonstrated that creatinine and endoleak were independent factors in predicting late death (95% CI, 3.4-26%, P < 0.01). The overall cardiovascular event-free survival was 88.9% +/- 2.1% at 30 days, 87.2% +/- 4.1% at 1 year, and 81.4% +/- 6.3% at 2 years. CT angiography identified the complete or partial thrombosis of the false lumen to be 95.7%.

CONCLUSIONS

Endovascular repairing with stent-graft is safe, feasible, and able to treat type B aortic dissection in all phases. However, chronic renal dysfunction was an independent factor which contributed to a lower survival rate of chronic phase patients.

Endovascular treatment of thoracic aortic diseases: Combined experience from the EUROSTAR and United Kingdom Thoracic Endograft registries

PURPOSE

The objective of this study was to assess the initial and 1-year outcome of endovascular treatment of thoracic aortic aneurysms and dissections collated in the European Collaborators on Stent Graft Techniques for Thoracic Aortic Aneurysm and Dissection Repair (EUROSTAR) and the United Kingdom Thoracic Endograft registries.

METHODS

Four hundred forty-three patients underwent endovascular repair of thoracic aortic disease between September 1997 and August 2003 (EUROSTAR, 340 patients; UK, 103 patients). Patients represented 4 major disease groups: degenerative aneurysm (n = 249), aortic dissection (n = 131), false anastomotic aneurysm (n = 13), and traumatic aortic injury (n = 50).

RESULTS

Mean age in the entire study group was 63 years. Fifty-two percent of patients were deemed at high risk for open surgery because of major comorbidity. Sixty percent of patients underwent an elective procedure, and 35% required emergency treatment. Conventional indications for treatment of aortic dissection, including aortic expansion, continuous pain, rupture, or symptoms of branch occlusion constituted the basis for endograft placement in 57% of patients, whereas in 43% of patients aortic dissections were asymptomatic. Primary technical success was obtained in 87% of patients with degenerative aneurysm and in 89% with aortic dissection. Paraplegia was a postoperative complication in 4.0% of patients with degenerative aneurysm and 0.8% of patients with aortic dissection (not significant). Thirty-day mortality in the entire study group was 9.3%, with mortality rates after elective procedures of 5.3% for degenerative aneurysms and 6.5% for aortic dissection. Mortality for degenerative aneurysm after emergency repair was higher (28%; P <.0001) then after elective procedures. For aortic dissection the emergency repair rate was 12% (not significant compared with elective repair of aortic dissection, and P = .025 compared with emergency repair of degenerative aneurysm). One-year follow-up was complete in 195 patients. The outcome at 1 year was more favorable for aortic dissection than for degenerative aneurysm with regard to aortic expansion (0% vs 15%; P = .001) and late survival (90% vs 80%; P = .048). In the groups with false anastomotic aneurysm and traumatic aortic injury, 30-day mortality rates were 8% and 6%, respectively.

CONCLUSION

This multicenter experience demonstrates acceptable rates for operative mortality and paraplegia after endovascular repair of thoracic aortic disease. Outcome after 30 days and 1 year was more favorable for aortic dissection than for degenerative aneurysm. However, the durability of this technique is currently unknown, and continued use of registries should provide data from long-term follow-up.

Is medical therapy still the optimal treatment strategy for patients with acute type B aortic dissections?

OBJECTIVE

The optimal treatment of patients with acute type B dissections continues to be debated.

METHODS

A 36-year clinical experience of medical and surgical treatments in 189 patients was retrospectively analyzed (multivariable Cox proportional hazards model) with respect to three outcome end points: all deaths, freedom from reoperation, and freedom from late aortic complications or death. Propensity score analysis identified 2 quintiles (quintiles I and II, consisting of 142 comparable patients) for further comparison of the effects of surgical versus medical treatment.

RESULTS

Shock (hazard ratio 14.5, 95% confidence interval 4.7-44.5, P <.001) and visceral ischemia (hazard ratio 10.9, 95% confidence interval 3.9-30.3, P <.001) largely predominated as determinants of death, along with 6 other risk factors (arch involvement, rupture, stroke, previous sternotomy, and coronary or lung disease), which roughly doubled the hazard of death. Female sex was a significant but weaker predictor of death. Renal dysfunction, year of presentation, age, and mode of therapy (medical vs surgical) had no important bearing on overall survival. The actuarial survival estimates for all patients were 71%, 60%, 35%, and 17% at 1, 5, 10, and 15 years, respectively, and were similar for the medical and surgical patients. Reoperation and late aortic complications were predicted by the presence of Marfan syndrome. For the propensity-matched patients in quintiles I and II, survival, freedom from reoperation, and freedom from aortic complications were almost identical in the medically treated and surgical subsets.

CONCLUSIONS

The prognosis for patients with acute type B aortic dissection is bleak and determined primarily by dissection-related and patient-specific risk factors, which do not appear to be readily modifiable.

Acute and chronic aortic dissection

Each year acute aortic dissection is diagnosed in 2,000 individuals in the United States. Acute aortic dissection is no longer a catastrophic event because this problem can be rapidly diagnosed with current medical technology, and therefore promptly treated with medication and surgery. Consequently, patients with aortic dissection can survive for 10 to 20 or more years after the initial event. However, there is considerable current debate regarding the most optimal technique(s) for the diagnosis of aortic dissection. Moreover, little information is available on the best methods for the long-term assessment and treatment of patients who have been successfully treated for acute aortic dissection. This report reviews the current techniques that are available for the diagnosis of aortic dissection and discusses the important issues regarding the acute and long-term treatment of patients with this problem.

Aortic dissection: percutaneous management with a separating stent-graft--preliminary results

The authors used a separating stent-graft to treat Stanford type B aortic dissection. The separating stent-graft consists of two stents: a stent-graft and an inner bare stent. The separating stent-graft has three parts: a proximal stent, a graft made of synthetic polyester textile fiber, and a distal stent. A 12-F introducing sheath was used. After the separating stent-graft was placed, false-lumen thrombosis was evident in all six patients during a follow-up period of 206 days. The major advantages of this technique are that a cutdown and blood pressure control are not required.

Delayed chronic type A dissection following CABG: implications for evolving techniques of revascularization

BACKGROUND

Postoperative dissection in some patients is related to manipulation of the aorta and accounts for 3% to 5% of deaths after cardiac surgery.

METHODS

Between 1987 and 1999, 109 patients with previous cardiac operations were treated for chronic type A dissection. In 31 of the patients, the etiology was related to aortic manipulation. Twenty-one patients (17 men, 4 women; 67+/-13 years of age) had isolated coronary artery bypass grafting (CABG) as their first operation and were reviewed. The interval between operations was 52.9+/-47.3 months.

RESULTS

Reoperation was elective in 11 patients, urgent in 10 patients. Median maximal aortic diameter was 6.8+/-2.1 cm; 9 patients had major aortic insufficiency. The intimal tear was at the partial occlusion clamp site in 12 patients (57.1%), at the cross-clamping site in 4 patients (19.1%), and at the proximal anastomosis in 1 patient (4.8%); 4 patients (19.1%) had multiple tears at several sites. Cystic media necrosis was present in 9.5% of the patients, severe atherosclerosis in 47.6% of the patients, and 42.9% of the patients had both. Nine patients (42.9%) underwent a modified Bentall procedure, 12 patients (57.1%) underwent a supracoronary anastomosis, and all had open distal anastomosis. There were two (9.5%) hospital deaths and three (14.3%) postoperative strokes. Freedom from cardiac or aorta-related mortality was 85.7% at a mean follow-up of 49.3 months.

CONCLUSIONS

In patients who develop type A dissection of the aorta after previous CABG, the intimal tear most often is at partial occlusion clamp site. This complication is associated with morbidity and mortality. It remains to be seen whether the use of partial occlusion clamps on the pulsating and often diseased aorta during off-pump coronary artery bypass (OPCAB) will increase the risk of delayed iatrogenic dissections.

Epidemiology and clinicopathology of aortic dissection

STUDY OBJECTIVES

To determine the incidence and mortality as well as to analyze the clinical and pathologic changes of aortic dissection.

DESIGN AND SETTING

A population-based longitudinal study over 27 years on a study population of 106,500, including 66 hospitalized and 18 nonhospitalized consecutively observed patients.

MEASURES

Analysis of data from the medical, surgical, and autopsy records of patients with aortic dissection.

RESULTS

Altogether, 86 cases of aortic dissection were found in 84 patients, corresponding to a 2.9/100,000/yr incidence. Sixty-six of the 84 patients (79%) were admitted to the hospital, and 18 patients (21%) died before admission. Their ages ranged from 36 to 97 years, with a mean of 65. 7 years. The male/female ratio was 1.55 to 1. A total of 22.7% of the hospitalized patients died within the first 6 h, 33.3% within 12 h, 50% within 24 h, and 68.2% within the first 2 days after admission. Six patients were operated on, with a perioperative mortality of two of six patients and a 5-year survival of two of six patients. All patients who were not operated on died. Pain was the most frequent initial symptom. Every patient had some kind of cardiovascular and respiratory sign. Neurologic symptoms occurred in 28 of 66 patients (42%). Five patients presented with clinical pictures of acute abdomen and two with acute renal failure. Trunk arteries were affected in 33 of the 80 autopsied cases (41%), and rupture of aorta was seen in 69 cases (86%). In five cases, spontaneous healing of dissection was also found. The ratio of proximal/distal dissections was 5.1 to 1. All 18 prehospital cases were acute. Fifty-nine cases (89.4%) were acute at admission, and 7 cases (10.6%) were chronic dissections. Hypertension and advanced age were the major predisposing factors.

CONCLUSION

Aortic dissection was the initial clinical impression in only 13 of the 84 patients (15%). Thus, 85% of the patients did not receive immediate appropriate medical treatment. For this reason, these late-recognized and/or unrecognized cases may be regarded as an untreated or symptomatically treated group, whose course may resemble the natural course of aortic dissection.

Delineation of the extracellular determinants of ultrasonic scattering from elastic arteries

Elastic arteries consist of three primary components: elastin fibers, extracellular collagen matrix and smooth muscle cells. However, the relative contribution of elastin and collagen fibers to overall ultrasonic scattering from an intact arterial wall is poorly understood. To define the principal source of extracellular scattering from the medial layer of elastic arteries, canine ascending aortas (n = 10) were excised, fixed and sectioned for insonification. Subsequently, aortic specimens were restudied after treatment to dissolve all tissue components except extracellular collagen matrix (n = 5) and elastin fibers (n = 5). Histological staining revealed very few elastin fibers and sparse intact collagen in collagen-isolated and elastin-isolated tissues, respectively. Integrated backscatter, attenuation and backscatter coefficients differentiated these two treated tissues. The backscatter coefficient for elastin-isolated tissue demonstrated a fivefold increase over collagen-isolated tissue, suggesting that elastin fibers represent a primary scattering component within elastic arteries, and the collagen fibers may provide a secondary component of scattering.

Etiologic factors of acute aortic dissection in children and young adults

Current concepts in the pathophysiology and predisposing conditions of acute aortic dissection in children, adolescents, and young adults are presented. Timely diagnosis is required for this life-threatening condition. Most children and adolescents with aortic dissection have congenital cardiovascular anomalies. Certain heritable disorders involving connective tissue also predispose to this disorder. Newer associations include cocaine abuse and weight lifting. To facilitate early diagnosis, the salient physical findings of the known predisposing conditions are reviewed. Clinical presentation and diagnostic imaging of aortic dissection are briefly summarized. Physicians working in an acute care setting, particularly in the emergency room, should be aware of disorders predisposing to acute aortic dissection in the pediatric and young adult population. Practitioners conducting school or college preparticipation sports evaluations can make use of such information in their assessment of risk for sudden death.

Nonsurgical reconstruction of thoracic aortic dissection by stent-graft placement

BACKGROUND

The treatment of thoracic aortic dissection is guided by prognostic and anatomical information. Proximal dissection requires surgery, but the appropriate treatment of distal thoracic aortic dissection has not been determined, because surgery has failed to improve the prognosis.

METHODS

We prospectively evaluated the safety and efficacy of elective transluminal endovascular stent-graft insertion in 12 consecutive patients with descending (type B) aortic dissection and compared the results with surgery in 12 matched controls. In all 24 patients, aortic dissection was diagnosed by magnetic resonance angiography. In each group, the dissection involved the aortic arch in 3 patients and the descending thoracic aorta in all 12 patients. With the patient under general anesthesia, either surgical resection was undertaken or a custom-designed endovascular stent-graft was placed by unilateral arteriotomy.

RESULTS

Stent-graft placement resulted in no morbidity or mortality, whereas surgery for type B dissection was associated with four deaths (33 percent, P=0.09) and five serious adverse events (42 percent, P=0.04) within 12 months. Transluminal placement of the stent-graft prosthesis was successful in all patients, with no leakage; full expansion of the stents was ensured by balloon inflation at 2 to 3 atm. Sealing of the entry tear was monitored during the procedure by transesophageal ultrasonography and angiography, and thrombosis of the false lumen was confirmed in all 12 patients after a mean of three months by magnetic resonance imaging. There were no deaths or instances of paraplegia, stroke, embolization, side-branch occlusion, or infection in the stent-graft group; nine patients had postimplantation syndrome, with transient elevation of C-reactive protein levels and body temperature plus mild leukocytosis. All the patients who received stent-grafts recovered, as did seven patients who underwent surgery for type B dissection (58 percent) (P=0.04).

CONCLUSIONS

These preliminary observations suggest that elective, nonsurgical insertion of an endovascular stent-graft is safe and efficacious in selected patients who have thoracic aortic dissection and for whom surgery is indicated. Endoluminal repair may be useful for interventional reconstruction of thoracic aortic dissection.

Acute thoracic aortic dissection: the basics

With an increasing incidence, aortic dissection is the most common acute illness of the aorta. In the setting of chronic hypertension, with or without other risk factors for aortic dissection, this diagnosis should be considered a diagnostic possibility in patients presenting to the emergency department with acute chest or back pain. Left untreated, about 75% of patients with dissections involving the ascending aorta die within 2 weeks of an acute episode. But with successful initial therapy, the 5-year survival rate increases to 75%. Hence, timely recognition of this disease entity coupled with urgent and appropriate management is the key to a successful outcome in a majority of the patients. This article reviews acute thoracic aortic dissection, including ED diagnosis and management.

Early and late outcome of operated and non-operated acute dissection of the descending aorta

OBJECTIVE

At present debate continues concerning the optimal mode of treatment for type B dissections. Controversies are mainly due to discordant results regarding survival following medical or surgical treatment. We assessed early and long-term outcome of acute dissection of the descending aorta treated by emergency aortic replacement, medical treatment or delayed surgery.

METHODS

Between 1980 and 1995, 225 patients were hospitalized in the medical or surgical department of our institution with the diagnosis of acute type B aortic dissection. A total of 38 patients (16.8%) underwent replacement of the descending aorta within the first week after hospital admission. Primary indications for immediate surgery were: rupturing aneurysm (n = 15), diameter of the descending aorta (n = 13), malperfusion of the thoracoabdominal aorta (n = 8) and pseudocoarctation syndrome with uncontrollable hypertension (n = 2). All other patients (n = 187) underwent primary conservative treatment on the intensive care unit, including appropriate anti-hypertensive medication. In 12 of them, surgery was denied because of age or significant concomitant diseases.

RESULTS

Hospital mortality after urgent or emergency surgery was 21% (8/38 patients) for the overall time period. There has been a significant decrease in hospital mortality during the last 5 year-period (12% versus 30% between 1980 and 1994). Causes of death were: cardiac failure in 3, bleeding complications in 2, postoperative mesenteric ischemia in 2 and septicemia in one patient. From the 30 operative survivors, 9 (30%) patients required further surgery on the native aorta after a mean follow-up of 48 +/- 13 months. Hospital mortality during conservative treatment was 17.6% (33/187 patients). Main causes of death were rupture in 14, thoraco-abdominal malperfusion in 13 and cardiac failure in 3 patients, whereas in 3 patients, the cause of death could not be evaluated. In this group, 9 patients had to be shifted to early surgery during the initial hospitalization because of impending rupture (n = 4), rapidly increasing diameter (n = 2) and suspicion of intestinal ischemia (n = 3). After hospital discharge, surgery for chronic dissection was performed in 47 patients, mainly because of expanding descending aortic aneurysm. Hospital mortality was 8% (4/47 patients). Actuarial survival rates after surgery during the first admission were 85 +/- 6% at 5 years and 61 +/- 8% at 10 years, versus 76 +/- 5 and 50 +/- 7% respectively, following conservative treatment (P < 0.001).

CONCLUSION

Nowadays, acute type B dissection can be treated surgically with a reasonable perioperative risk. Despite aggressive anti-hypertensive treatment, hospital mortality of primary conservative treatment is still high and a substantial percentage of patients requires surgery during initial hospitalization. Main causes of death in both groups are rupture and abdominal malperfusion: therefore, closed clinical and radiologic assessment of the whole thoraco-abdominal aorta is of utmost importance. Long-term results are satisfying; unlimited radiographic follow-up allows for detection of potential severe complications and for proper planning of elective reoperations when indicated.