Assessment of transesophageal Doppler echography in dissecting aortic aneurysm

To assess the clinical value of transesophageal Doppler echography in the diagnosis of dissecting aortic aneurysm, both transesophageal and conventional echograms were performed in 22 cases of dissecting aortic aneurysm. Of the 22 patients, 17 underwent angiography; 8, X-ray computed tomography; 4, both; and 12, surgery. The performance of each method was assessed in the following four segments: A, ascending aorta; B, aortic arch; C, thoracic descending aorta; and D, upper abdominal aorta. The results by angiography were presumed to be correct. In the group of 17 patients who underwent angiography, the rate of correct detection of an intimal flap using the transesophageal approach was 100% in all four segments, significantly better than detection by the conventional approach (segment A, 65%; segment B, 47%; segment C, 35%; segment D, 53%) (p less than 0.01), and the rate of correct detection of the entry sites using the transesophageal approach was 100%, significantly better than that by conventional approach (42%) (p less than 0.05). X-ray computed tomography was not capable of detecting the site of entry in all cases. The presence of thrombus, aortic regurgitation and pericardial hemorrhage were all revealed clearly by the transesophageal approach, and the results were partly proved by other methods. In conclusion, transesophageal Doppler echography provides a rapid and accurate method of diagnosing and evaluating dissecting aortic aneurysm and permits prompt initiation of appropriate treatment.     

Intimal tear without hematoma: an important variant of aortic dissection that can elude current imaging techniques

BACKGROUND: The modern imaging techniques of transesophageal echocardiography, CT, and MRI are reported to have up to 100% sensitivity in detecting the classic class of aortic dissection; however, anecdotal reports of patient deaths from a missed diagnosis of subtle classes of variants are increasingly being noted. METHODS AND RESULTS: In a series of 181 consecutive patients who had ascending or aortic arch repairs, 9 patients (5%) had subtle aortic dissection not diagnosed preoperatively. All preoperative studies in patients with missed aortic dissection were reviewed in detail. All 9 patients (2 with Marfan syndrome, 1 with Takayasu's disease) with undiagnosed aortic dissection had undergone >/=3 imaging techniques, with the finding of ascending aortic dilatation (4.7 to 9 cm) in all 9 and significant aortic valve regurgitation in 7. In 6 patients, an eccentric ascending aortic bulge was present but not diagnostic of aortic dissection on aortography. At operation, aortic dissection tears were limited in extent and involved the intima without extensive undermining of the intima or an intimal "flap." Eight had composite valve grafts inserted, and all survived. Of the larger series of 181 patients, 98% (179 of 181) were 30-day survivors. CONCLUSIONS: In patients with suspected aortic dissection not proven by modern noninvasive imaging techniques, further study should be performed, including multiple views of the ascending aorta by aortography. If patients have an ascending aneurysm, particularly if eccentric on aortography and associated with aortic valve regurgitation, an urgent surgical repair should be considered, with excellent results expected.     

Incremental value of live/real time three-dimensional transesophageal echocardiography over the two-dimensional technique in the assessment of aortic aneurysm and dissection

We compared findings from intraoperative live/real time three-dimensional transesophageal echocardiography (3DTEE) and two-dimensional transesophageal echocardiography (2DTEE) with surgery in 67 patients having aortic aneurysm and/or aortic dissection. Of these, 20 patients had aortic aneurysm without dissection, 21 aortic aneurysm and dissection, and 26 aortic dissection without aneurysm. 3DTEE diagnosed the type and location of aneurysm correctly in all patients unlike 2DTEE, which missed an aneurysm in one case. There were four cases of aortic aneurysm rupture. Three of them were diagnosed by 3DTEE but only one by 2DTEE, and one missed by both techniques. The mouth of saccular aneurysm, site of aortic aneurysm rupture, and communication sites between perfusing and nonperfusing lumens of aortic dissection could be viewed en face only with 3DTEE, enabling comprehensive measurements of their area and dimensions as well as increasing the confidence level of their diagnosis. In all patients with aortic dissection, 3DTEE enabled a more confident diagnosis of dissection because the dissection flap when viewed en face presented as a sheet of tissue rather than a linear echo seen on 2DTEE which can be confused with an artifact. 2DTEE missed dissection in one patient. In six cases the dissection flap involved the right coronary artery orifice by 3DTEE and surgery. These were missed by 2DTEE. Aortic regurgitation severity was more comprehensively assessed by 3DTEE than 2DTEE. Aneurysm size by 3DTEE correlated well with 2DTEE and surgery/computed tomography scan. In conclusion, 3DTEE provides incremental information over 2DTEE in patients with aortic aneurysm and dissection.     

The complementary role of magnetic resonance imaging, Doppler echocardiography, and computed tomography in the diagnosis of dissecting thoracic aneurysms

Non-ECG gated MRI was compared with 2DE and/or CT scans in 10 patients with dissecting aneurysms proven by angiography and/or surgery. Patient ages ranged from 48 to 85 years (mean 69.6). Six had DeBakey type I dissections and four had DeBakey type III dissections. MRI was diagnostic for aortic dissection in nine cases and suggestive in the tenth. 2DE was diagnostic in six out of nine patients, suggestive in two patients, and nondiagnostic in one patient. CT was diagnostic in the three cases in which it was employed. MRI demonstrated a dilated ascending aorta with thickened walls in all type I dissections as well as an intimal flap and slow flow in the false channel in four patients. In the other two patients with type I dissection, MRI detected the intimal flap in the descending aorta but not in the ascending aorta, whereas 2DE revealed the ascending aortic intimal flap in both of these patients and CT showed it in one of them. In the type III dissections, MRI demonstrated a thickened wall and thrombus in the lumen in all four cases, and the intimal flap in three out of the four. 2DE excluded ascending aortic involvement in all three type III dissections. Six other patients with fusiform dilated ascending aortas had no evidence of dissection by MRI, 2DE, and aortography. Thus, non-ECG gated MRI alone or in combination with 2DE and/or CT is useful in the diagnosis of dissecting thoracic aneurysm and in assessing the extent of the dissection. In addition, the differentiation of dissecting aneurysms of the aorta from fusiform dilatation of the aorta is made possible by these noninvasive techniques.     

3D morphometric analysis of ascending aorta as an adjunctive tool to predict type A acute aortic dissection

BackgroundAcute type A aortic dissection (AAAD) is a pathological process that implicates the ascending aorta and represents a surgical emergency burdened by high mortality if not promptly treated in the first hours of onset. Despite best efforts, the annual incidence rates of aortic dissection has remained stable over the past decades. We measured aortic dimensions (aortic diameters, area, length and volume) using 3D multiplanar reconstruction imaging with the purpose of refining the risk- morphology for AAAD.MethodsComputerized tomography angiography studies of three groups were compared retrospectively: patients affected by AAAD (AAAD group; n=71), patients affected by aortic aneurysm and subsequently subjected to ascending aorta replacement (Aneurysm, n=77) and a healthy aorta’s group (Control, n=75).ResultsMean diameters of AAAD (4.9 cm) and Aneurysm (5.1 cm) aortas were significantly larger than those of the control group (3.4 cm). In AAAD patients, an ascending aorta diameter greater than 5.5 cm was observed in 18% of patients. Multiple comparisons showed statistically significant differences among mean of the ratio of aortic root area to height between the three groups (P<0.001). In frontal and sagittal planes, the length of the ascending aorta was significantly greater in patients affected by aortic pathology (AAAD and aneurysm) than in the control group (P<0.001). Significant differences were confirmed when indexing the aortic length to patient’s height and BSA, and the aortic volume to patient’s BSA.ConclusionsMaximum transverse diameter, considered separately, is not the best predictor of aortic dissection. In our opinion, the introduction into clinical practice of measurements of the area, length, and volume of the aorta, as absolute or indexed values, could improve the selection of patients who would benefit from preventive surgical aortic replacement.     

Imaging of the Postsurgical Aorta in Marfan Syndrome

Marfan syndrome is a heritable multisystem connective tissue disease and is the most common genetic cause of aortic disease. Guidelines for surgical repair and recommendations for surveillance imaging aim to prevent aneurysm rupture, aortic dissection, and death. Options for proximal aorta repair include the modified Bentall procedure and valve-sparing aortic root repairs. Hemiarch and total arch replacement are options for aortic arch repair, and the elephant trunk procedure is a special two-staged total arch repair facilitating future descending aorta repair. Endovascular repair is not currently considered an acceptable long-term treatment option in Marfan syndrome but may be performed when open repair is not feasible or in the acute setting as a bridge to definitive surgical treatment. After an initial surgery, patients remain at risk for new aortic dissection, propagation of a pre-existing aortic dissection, and new or enlarging aortic aneurysm. Anastomotic pseudoaneurysm is a potential postsurgical complication at multiple sites including proximal and distal aortic anastomoses, coronary anastomoses, and intercostal and visceral artery patches. Patients undergoing endovascular repair are at increased risk of endoleak and aortic dissection. CT and MR angiography are the main imaging modalities for surveillance of the aorta in Marfan syndrome and are capable of demonstrating these complications, as well as expected postsurgical appearances. 4D flow MRI is an emerging technique providing hemodynamic information that may risk-stratify aneurysms better than size alone and help predict future aortic events.     

Involvement of thoracic aorta revealing temporal arteritis. Three cases

INTRODUCTION: Temporal arteritis involves large vessels in 15% of cases. Their discovery is usually late, commonly several years after the diagnosis. EXEGESIS: We describe three cases of temporal arteritis with thoracic aorta involvement: two patients presented with aorta aneurysm which revealed temporal arteritis, one patient had aortic insufficiency. Clinical features of temporal arteritis were absent in two patients. Temporal artery biopsy, performed in two cases, was positive. Two patients were treated with corticosteroids, associated in one case with immunosuppressive agent. Surgery was necessary in all patients. CONCLUSION: Thoracic aorta involvement in Horton's disease is most often discovered when corticotherapy is decreased. Aneurysm rupture or aortic dissection in aortic affection are the major complication. Patient with thoracic aorta involvement need a clinical and radiological follow up over long period.     

Annulo-ectasing disease of the aorta: apropos of 10 cases

Ten patients were investigated and operated for severe aortic regurgitation due to dystrophic aortic dilatation. This is the third commonest cause of pure aortic regurgitation (18 p. 100) operated at Necker Hospital during the same period. This condition, comprising aneurysm of the ascending aorta, dilatation of the aortic ring and dystrophic aortic valves, is often responsible for severe aortic regurgitation and is noteworthy because of the associated risk of aortic dissection. Cardiovascular surgery is indicated and usually includes replacement of the ascending thoracic aorta with aortic valve replacement.     

Dystrophic aortic valve insufficiency

Although dystrophic aortic regurgitation is considered to be a rare condition, if aortic regurgitation due to cystic media-necrosis which usually presents with annulo-aortic ectasia and regurgitation due to dystrophic aortic valves are included, it becomes a relatively common cause of aortic regurgitation. In the authors' experience of 313 patients operated for pure chronic aortic regurgitation, approximately 30% had dystrophic lesions and this was the second most common cause of aortic regurgitation after acute rheumatic fever. The clinical presentation is variable: excluding annulo-aortic ectasia, the other features of dystrophic aortic regurgitation are less well known. Eighty-nine cases without aneurysm of the ascending thoracic aorta were recensed and analysed in a French Cooperative study. They were divided into two groups with respect to the diameter of the ascending aorta measured by echocardiography. The incidence of late postoperative complications of the ascending aorta was higher in patients with a dilated aorta. The diagnosis of dystrophic aortic regurgitation is easy in patients with an aneurysm of the ascending aorta: in other cases, transoesophageal echocardiography is very useful for evaluating the valvular lesions. Surgical treatment of pure dystrophic aortic regurgitation with an aneurysm of the ascending aorta is well established but the best management of aortic regurgitation associated with only mildly dilated aorta is debatable.     

Value of echocardiography in patient follow-up after surgically corrected type A aortic dissection.

BACKGROUND: To identify patients (pts) at risk of late complications, follow-up after surgery for type A aortic dissection is essential. We assessed the value of echocardiography to monitor patients after surgery for type A aortic dissection. METHODS: 80 out of 108 pts operated between 1989 and 1999 for type A aortic dissection survived surgery. 62 pts with at least one TEE, CT or MRI examinations during follow-up were included in this study. All pts had transthoracic echocardiography (TTE), 53 transesophageal echocardiography (TEE), 51 had CT, and 39 had MRI. RESULTS: At the first follow-up, 12 of 48 pts with aortic valve sparing surgery presented with aortic insufficiency >I degrees detected using echocardiography. 16 pts evolved a distal aortic aneurysm of over 5 cm, all seen in TEE, CT and MRI. A distal intimal flap was present in 39 pts and could be seen in TEE, CT and MRI in all patients. A new proximal aortic root dissection took place in 5 pts. Progressive aortic pathology led to reoperation in 9 pts. TEE was especially useful in 2 pts to confirm redissection, in 1 pt to rule out redissection assumed by CT, and in 1 with paraprosthetic blood flow after ascending aortic replacement. MRI led to additional information in 1 patient with false aneurysm of the distal anastomosis and 1 with redissection not seen in TEE 6 month before. CT and MRI were superior to TEE in demonstrating aortic arch pathology, whereas TEE was more effective in showing the flow pattern and residual entry sites. CONCLUSIONS: Echocardiography is an effective and cost-saving diagnostic tool to monitor pts after surgery for type A aortic dissection, and should be the method of choice to ascertain aortic pathology initially after surgery. Follow-up intervals and need for additional CT or MRI should be determined afterwards according to specific pathologies.     

单纯主动脉瓣反流病因超声心动图与手术对照分析

目的 探讨行手术治疗的单纯主动脉瓣反流病因分布.方法 手术治疗的单纯主动脉瓣重度反流患者86例,通过超声心动图观察主动脉瓣反流、瓣膜形态及异常回声、升主动脉内径,综合超声心动图、手术所见、部分病理结果和临床资料确定最终病因.结果 在手术治疗单纯主动脉瓣反流患者中,瓣膜松弛、感染性心内膜炎和升主动脉夹层分别排行前3位病因.风湿性心脏病、退行性变、白塞病排行并列第4位.其余病因为主动脉瓣二叶瓣和梅毒.结论 本组行手术治疗的单纯主动脉瓣反流病人中,病因以瓣膜病为主,超声心动图在确定病因方而起重要作用.     

胸主动脉病变术中应用经食管超声心动图的初步探讨

目的：探讨胸主动脉疾病的术中应用经食管超声心动图（ＴＥＥ）的价值及适应证。方法：本文报道８例（１５～６３岁，平均年龄４４．５岁）不同类型胸主动脉疾病术中ＴＥＥ监测结果。病例包括先天性主动脉瓣上狭窄、升主动脉瘤、主动脉夹层及主动脉夹层伴假性动脉瘤、胸降主动脉假性动脉瘤、主动脉瓣脱垂等。结果：８例患者的术中检查与术前诊断全部吻合。术中ＴＥＥ发现１例主动脉夹层累及左锁骨下动脉，而术前磁共振成像未能提示。此外，术中ＴＥＥ还显示２例胸降主动脉内的粥样硬化斑块。结论：初步显示术中ＴＥＥ可即刻评价手术效果，对拟行主动脉瓣成形术的患者最有价值；为避免升主动脉粥样斑块的脱落导致术后体循环尤其是脑栓塞，对于高龄患者也积极提倡术中ＴＥＥ监测。     

Magnetic resonance tomography in the assessment of questionable aneurysm of the thoracic aorta with or without dissection of the intima

To assess the value of MRI in the diagnosis of aneurysm of the thoracic aorta with suspected or known dissection 23 patients were imaged with cardiac gating. Seven patients (group 1) had known dissection of the thoracic aorta; in 16 patients (group 2) an aneurysm was suspected by chest x-ray or 2D-echocardiography. Reference methods were: x-ray, 2D-echocardiography, angiography, and computered tomography. In the first group MRI clearly identified the intimal flap, could differentiate between true and false lumen, slow flow, and thrombus, respectively. In the second group MRI could exclude a dissection of the ectatic part of the thoracic aorta in 11 patients and demonstrate paracardiac or mediastinal mass in five patients. MRI can serve as an important diagnostic tool in known or suspected aneurysm of the thoracic aorta.     

Surgical techniques. Ascending aorta

Aneurysm and dissection are the most common diseases affecting the ascending aorta. Graft replacement of the ascending aorta is a straightforward cardiovascular procedure with excellent early and late results. When aneurysm or dissection extends into the aortic sinuses or arch, management becomes more complex and may entail replacement of the aortic root, aortic valve, or a portion of the aortic arch using hypothermic circulatory arrest. The optimal root prosthesis depends on several patient- and procedure-related variables. Valve-sparing procedures confer many long-term advantages and should be considered in all cases where the aortic valve leaflets are normal. The Ross procedure, although ideally suited for isolated aortic valve disease in young patients, may be applicable to some patients with combined aortic valve and ascending aortic disease, unless there is evidence of a systemic connective tissue disorder.     

Transesophageal Doppler echocardiography in the diagnosis of dissecting aortic aneurysm

Transesophageal Doppler echocardiography (TEDE) was performed in three patients with proven or suspected DeBakey type I and type III aortic dissection. Case 1: A 66-year-old woman, with DeBakey type I aortic dissection. Clear images of a widened dissected aorta and an intimal flap were obtained in both the ascending and descending aorta, including the aortic arch. The site of an entry into the false lumen was identified by the defect of the intimal flap and the pulsatile entry flow through it. The reentry into the true lumen was also identified near the orifice of the celiac trunk. In this case, the observation was performed using this technique during the operation; i.e., replacement of the ascending aorta with an artificial graft. Case 2: A 77-year-old man, DeBakey type III aortic dissection. The study was performed after surgery which consisted of replacement of the descending aorta with an artificial graft. TEDE provided clear images of the artificial graft, the aorta, and their boundaries. The remaining intimal flap was clearly confirmed. Case 3: An 80-year-old man, DeBakey type III aortic dissection. In this case, though abdominal echography suggested aortic dissection, angiography and X-ray CT failed to facilitate the diagnosis. Only TEDE confirmed the diagnosis. The abnormal flow via the entry directing toward the false lumen was clearly demonstrated on the color Doppler images. We therefore conclude that TEDE is a useful and reliable means of diagnosing dissecting aortic aneurysm.     

Aneurysms of the ascending aorta: Diagnostic features and prognosis in patients with marfan's syndrome versus hypertension

Background: In Marfan's syndrome progressive dilation of the sinuses of Valsalva, the supra-aortic ridge and the ascending aorta are well characterized abnormalities likely to set the stage for severe aortic sequelae accounting for 70% of lethal complications. However, the specific anatomical, clinical, and prognostic profiles of aortic pathology are less well characterized in the setting of patients with Marfan's syndrome symptomatic from aortic complications. Hypothesis: The study was designed to characterize the spectrum of anatomical, clinical, and prognostic profiles of thoracic aortic disease in symptomatic patients with Marfan's syndrome compared with patients with arterial hypertension. Noninvasive imaging techniques were used for comprehensive mapping of aortic pathology associated with Marfan's syndrome. Methods: Thirty-five consecutive patients with Marfan's syndrome (16 women, 19 men; mean age 35± 12 years) were imaged by transthoracic (TTE; n = 26) and transesophageal echocardiography (TEE; n = 11), contrast enhanced computed tomography (XCT; n = 16), or magnetic resonance techniques (MRI; n = 14). Diagnostic results were compared with both in-traoperati ve or angiographic findings and also with a group of 85 consecutive patients with aortic pathology associated with arterial hypertension. Results: Aortic pathology was more frequently confined to the ascending aorta (p<0.05) and aortic regurgitation was more prevalent in Marfan's syndrome than in arterial hypertension (p < 0.05). In 23 cases (66%) of dissection and 12 cases (34%) of nondissecting aneurysms, no Marfan-specific aortic macropathology was identified when compared with arterial hypertension. Diagnostic results of TEE, XCT, and MRI were all excellent; however, in contrast to the transesophageal ultrasound approach, transthoracic ultrasound was not useful in the detection of aortic dissection and intramural hemorrhage. Both 30-day (100 vs. 70%; p<0.05) and 5-year survival rates (91 vs. 57%; NS) were higher in patients with Marfan's syndrome than in those with arterial hypertension. Repeat surgery, however, was more frequently required in patients with Marfan's syndrome (25% vs. none in aortic aneurysm; p < 0.05). Conclusions: There are no macropathologic findings of the aorta specific for Marfan's syndrome. In patients with Marfan's syndrome with an inherently high rate of aortic complications, serial noninvasive imaging should be encouraged, preferably utilizing TEE or MRI.     

Postoperative follow-up of type A aortic dissectionexperience with 67 patients]

BACKGROUND: The surgical treatment of type A aortic dissection is usually palliative and most surviving patients remain at considerable risk to develop late postoperative complications; consequently, there is the need for careful long-term follow-up. The present study reports on our experience in the postoperative follow-up of a consecutive series of patients with type A aortic dissection. METHODS: Between January 1986 and December 1996, 89 patients underwent emergency surgery for type A acute aortic dissection; the overall hospital mortality rate was 22% (20/89). This study includes the 69 hospital survivors (49 men and 20 women). Forty-six patients had ascending aortic graft replacement, 13 patients underwent replacement of aortic valve and ascending aorta by a composite graft. The surgical repair was extended to the aortic arch in 5 patients. All patients were serially evaluated by clinical examination and imaging techniques (transthoracic echocardiography in all patients, magnetic resonance imaging in 40, transesophageal echocardiography in 33 and computed tomography in 25). Follow-up was complete in 97% of patients (two patients were lost to follow-up and excluded from the study) and extended to a maximum of 152 months (mean 74 +/- 39 months). The postoperative quality of life was assessed by a questionnaire in 51 current survivors. Risk factors for cardiovascular death, reoperation and poor quality of life were investigated with univariate and multivariate analysis. RESULTS: During the follow-up period 15 patients (22%) died; in 13 cases death was due to cardiovascular causes and in 6 of them it was related to aortic disease. The Kaplan-Meier survival was 92 +/- 3%, 87 +/- 5%, 78 +/- 6% and 70 +/- 8% at 2, 4, 6 and 8 years, respectively. A persistent aortic dissection was demonstrated in 50 patients (75%) and 42 of them showed the presence of flow in the false lumen. A dilatation of one or more aortic segments was found in 59 patients (88%), with a diameter > or = 50 mm in 17 and > or = 60 mm in 8. In 30 patients who underwent transesophageal echocardiography the relation between aortic dimensions and flow pattern in the false lumen was examined; the presence of aneurysmal dilatation with a diameter > or = 50 mm was significantly correlated with a "high flow" pattern. Ten patients (15%) underwent reoperation from 13 to 83 months postoperatively. Reoperation was indicated for: sinus of Valsalva aneurysm and severe aortic regurgitation (2 patients), severe aortic regurgitation (2 patients), aneurysm of the arch (1 patient), thoracoabdominal aneurysm (1 patient), periprosthetic pseudoaneurysm (4 patients). The hospital mortality rate was 20% (2 patients). Sixty-two% of current survivors are asymptomatic; 30 patients returned to their predissection status. Quality of live is judged "good" by 23 patients, "fairly good" by 21 patients and "poor" by 7 patients. No significant independent risk factor for cardiovascular death, reoperation and poor quality of life was identified. CONCLUSIONS: The long-term prognosis after surgical treatment of type A aortic dissection is not satisfactory because of a significant risk of late complications. However, the results of our study can be judged fairly good, particularly if we consider the natural history of the disease.     

Acute and subacute dissection of the thoracic aorta: diagnostic importance of magnetic resonance tomography]

The purpose of this study was to retrospectively assess the reliability of ECG-triggered magnetic resonance imaging (MRI) for the diagnosis of acute and subacute thoracic aortic dissection and associated clinical epiphenomena. 67 patients were subjected to MRI; the diagnostic results were compared with morphological standards. 25 patients had type A, 12 patients type B dissection. In 30 cases a dissection was excluded. 17 patients with aortic dissection had acute onset of symptoms, 10 patients had subacute onset of symptoms. 17 patients revealed thrombosis of the false lumen, which was found in the descending aorta in 59% of the cases. Aortic regurgitation and pericardial effusion was most often associated with type A dissection (Table 1). Three patients were studied while on mechanical ventilation. Scan time for MRI ranged from 15 to 71 minutes with an average of 46 +/- 18 minutes. In this series no deleterious events were encountered related to MRI diagnostics. In contrast to previously published data using other noninvasive techniques the sensitivity of MRI was 100% for detecting a dissection in the ascending segment of the thoracic aorta. Moreover, the specificity of MRI for a dissection was 100% and thus higher than previously published data using transesophageal echocardiography. Sensitivity and specificity for detection and correct classification of type B dissection was 100% and 100% respectively (Table 2). In addition, MRI proved to be sensitive in detecting the formation of thrombus material in the false lumen of the ascending aorta (92%), the aortic arch (100%) and the descending segment (88%). Specificity for exclusion of suspected thrombus material even proved to be slightly higher with 100% in the ascending and descending aorta and 96.1% in the aortic arch (Table 3). The site of entry to a dissection was detected in 78%, with a sensitivity of 76% in the ascending and 92% in the descending aorta. The involvement of side branches in the dissecting process was identified in 60%. There were no false positive findings concerning side branch involvement. Aortic regurgitation and pericardial effusion were detected in 100% and 100%, respectively (Tables 1 and 2). MRI performed even in acute cases proved to be a atraumatic, safe and highly sensitive method to identify and classify acute and subacute dissections of the entire thoracic aorta. Limited patient access was not associated with an increased risk and mechanical ventilation did not interfere with MRI. These results may establish MRI as a valid and promising noninvasive technique to establish the diagnosis in patients with thoracic aortic dissection.(ABSTRACT TRUNCATED AT 400 WORDS)     

Degenerative aortic regurgitation

In view of the growing incidence of degenerative origin among the aetiologies of aortic regurgitation, we felt it interesting to report our experience of the surgical treatment of such patients. Out of 313 patients operated on for isolated chronic aortic regurgitation between 1974 and 1989, 102 (32.6%) had aortic regurgitation of degenerative origin and form the basis of this study. The patients were divided into group I (n = 48) without aneurysm of the ascending aorta and group II (54 patients) with anulo-aortic ectasia. The first group was further subdivided according to the diameter of the ascending aorta: in group Ia (23 patients) the aorta was normal with a root diameter of less than 40 mm, while in group Ib (25 patients) the aorta was enlarged (root diameter between 40 and 54 mm). There was no statistically significant difference between the pre-operative and operative parameters of patients in groups Ia and Ib. All underwent aortic valve replacement without associated surgery of the ascending aorta. During a mean follow-up of 58 months, five patients from group Ib had aortic dissection and in another three, an ascending aorta aneurysm developed. Reoperation was performed in six cases. No such complications occurred in group Ia. At 6 years, the proportion of patients free from complications related to the ascending aorta was 100% in group Ia vs 63 +/- 6% in group Ib (P less than 0.05). In group II, all the patients underwent aortic valve replacement. The modalities of repair of the ascending aorta differed with time.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evolution of aortic dissection after surgical repair

Patients after aortic dissection repair still have long-term unfavorable prognosis and need careful monitoring. The purpose of this study was to analyze the evolution of aortic dissection after surgical repair in correlation to anatomic changes emerging from systematic magnetic resonance imaging (MRI) follow-up. Between January 1992 and June 1998, 70 patients underwent surgery for type A aortic dissection. Fifty-eight patients were discharged from the hospital (17% operative mortality) and were followed by serial MRI for 12 to 90 months after surgery. In all, 436 postoperative MRI examinations were analyzed. In 13 patients (22.5%) no residual intimal flap was identified, whereas 45 patients (77.5%) presented with distal dissection, with a partial thrombosis of the false lumen in 24. The yearly aortic growth rate was maximum in the descending aortic segment (0.37 +/- 0.43 cm) and was significantly higher in the absence of thrombus in the false lumen (0.56 +/- 0.57 cm) (p <0.05). There were 4 sudden deaths, with documented aortic rupture in 2. Sixteen patients underwent reoperation for expanding aortic diameter. In all but 1 patient, a residual dissection was present (in 13 without any thrombosis of the false lumen). Close MRI follow-up in patients after dissection surgical repair can identify the progression of aortic pathology, providing effective prevention of aortic rupture and timely reoperation. Thrombosis of the false lumen appears to be a protective factor against aortic dilation.