Search PubMed⌕ Search

Biomedical subjects

D Hausmann

Publications and source records attributed to D Hausmann.

At least 37 records · Page 2Linked to original sources

Standardization of coronary vasomotor tone with intracoronary nitroglycerin.

Maximal, reproducible, and thus "standardized" dilation of epicardial coronary arteries can be easily achieved with intracoronary bolus administration of 0.1 mg nitroglycerin without considerable decrease in blood pressure. The addition of other nitrocompounds or calcium antagonists cannot increase coronary dilation after nitroglycerin, but may be hampered by adverse effects.

Blood Pressure↗

Angiographically silent atherosclerosis detected by intravascular ultrasound in patients with familial hypercholesterolemia and familial combined hyperlipidemia: correlation with high density lipoproteins.

OBJECTIVES: This study sought to evaluate the extent of atherosclerosis in coronary and iliac arteries in patients with heterozygous familial hypercholesterolemia or familial combined hyperlipidemia, using intravascular ultrasound imaging. BACKGROUND: Intravascular ultrasound imaging provides cross-sectional tomographic views of the vessel wall and allows quantitative assessment of atherosclerosis. METHODS: Forty-eight nonsmoking, asymptomatic patients with heterozygous familial hypercholesterolemia or familial combined hyperlipidemia underwent intravascular ultrasound imaging of the left anterior descending coronary, left main coronary and common iliac arteries. Angiography showed only minimal or no narrowing in these vessels. Intravascular ultrasound images obtained during catheter pullback underwent morphometric analysis. Plaque burden was expressed as the mean and maximal intimal index (ratio of plaque area and area within the internal elastic lamina) and as the percent of vessel surface covered by plaque. RESULTS: Intravascular ultrasound detected plaque more frequently than angiography in the left anterior descending (80% vs. 29%, respectively), left main (44% vs. 16%) and iliac arteries (33% vs. 27%). Plaque burden was higher in the left anterior descending (mean intimal index [+/- SD] 0.25 +/- 0.16) than in the left main (0.11 +/- 0.16, p < 0.001) and iliac arteries (0.02 +/- 0.04, p < 0.001). Angiography detected lumen narrowing only in coronary arteries with a maximal intimal index > or = 0.42 (left anterior descending artery) and > or = 0.43 (left main artery). The area within the internal elastic lamina increased with plaque area in the left anterior descending (r = 0.82, p < 0.001) and left main arteries (r = 0.53, p < 0.001). By stepwise multiple regression analysis, the strongest predictor for plaque burden in the left anterior descending artery was the level of high density lipoprotein (HDL) cholesterol and total/HDL cholesterol ratio for the left main artery. CONCLUSIONS: In patients with heterozygous familial hypercholesterolemia and familial combined hyperlipidemia, extensive coronary plaque is present despite minimal or no angiographic changes. Compensatory vessel enlargement and diffuse involvement with eccentric plaque may account for the lack of angiographic changes. Levels of HDL cholesterol and total/HDL cholesterol ratio are far more powerful predictors of coronary plaque burden than are low density lipoprotein cholesterol levels in these patients with early, asymptomatic disease.

Adult↗

[Profile of the effect of succinylcholine after pre-curarization with atracurium, vecuronium or pancuronium].

OBJECTIVE: The depolarizing muscle relaxant succinylcholine (SCh) may cause several side effects including muscle fasciculations and postoperative myalgia. These can be attenuated or even prevented by prior administration of a non-depolarizing muscle relaxant. A study was conducted to detect any difference between clinically established approaches concerning the successful prevention of muscular side effects and the influence on the time profile of SCh action. METHODS: The study included 64 patients (ASA status I or II) who underwent elective surgery under general anesthesia. The patients were divided into four groups; the demographic data did not differ significantly between the groups (see table 1). Before the injection of SCh (1 mg/kg) for intubation, the control group received saline (K), the other groups 5 mg Atracurium (A), 1 mg Vecuronium (V), or 1 mg Pancuronium (P), respectively. Neuromuscular block was quantified after train-of-four (TOF) stimulation of the tibial nerve by accelerometry at the toe. The first response was used to determine the onset time, duration of effect, and recovery index. It was noted whether SCh led to muscular activity. Postoperatively, patients were asked whether they experienced any muscular sequelae. Statistical significance was assessed at the 5% probability level by the Mann-Whitney-U test and the CHi2 test (Fisher's exact test, if appropriate). RESULTS: SCh caused a complete neuromuscular block in all patients. Most patients in the control group exhibited muscular contractions than in the other groups (see table 2), but only two patients reported light myalgia. There was no statistically significant difference between the four groups in the onset time and the recovery index of SCh. The duration of the effect was significantly reduced by atracurium (7.5 min) or vecuronium (8.2 min) as compared to the placebo (11.8 min) and pancuronium (13.5 min) (see figure). CONCLUSION: The prolonged duration of the SCh effect after pancuronium is probably due to the known inhibition of cholinesterase by pancuronium. The short duration of action after Atracurium and Vecuronium can be explained by the competitive antagonism at the receptor causing an increased amount of unbound SCh. The duration of the SCh effect may be influenced according to clinical needs by the choice of the non-depolarizing muscle relaxant. The significantly reduced duration of complete neuromuscular block after Atracurium or Vecuronium as precurarizing agents may be advantageous in cases where a fast recovery of spontaneous breathing is essential. If a reduction of the SCh blockade has to be avoided, Pancuronium should be selected for prior administration.

Adult↗

The safety of intracoronary ultrasound. A multicenter survey of 2207 examinations.

BACKGROUND: Intracoronary ultrasound (ICUS) is increasingly used in clinical practice to study the natural history of coronary artery disease and to assess the effects of intracoronary, catheter-based interventions. However, the risk associated with the procedure is not well documented. METHODS AND RESULTS: ICUS studies performed in 28 centers were retrospectively included; these centers agreed to contribute to the study among a total of 60 centers initially invited. Among the 2207 ICUS studies, 505 (23%) were performed in heart transplant recipients and 1702 (77%) in nontransplant patients. Indication for ICUS was diagnostic imaging in 915 (41%), drug testing in 244 (11%), and guidance for intracoronary interventions in 1048 patients (47%). There were no complications in 2034 patients (92.2%). In 87 patients (3.9%), complications occurred but were judged to be "not related" to ICUS by the operator. In 63 patients (2.9%), spasm occurred during ICUS imaging. In 9 patients (0.4%), complications other than spasm were judged to have a "certain relation" to ICUS, including acute procedural events in 6 (3 acute occlusion, 1 embolism, 1 dissection, and 1 thrombus) and major events in 3 patients (2 occlusion and 1 dissection; all resulting in myocardial infarction). In 14 patients (0.6%), complications with "uncertain relation" to ICUS were recorded, including acute procedural events in 9 (5 acute occlusion, 3 dissection, and 1 arrhythmia) and major events in 5 patients (2 myocardial infarction and 3 emergency coronary artery bypass surgery). The incidence of acute procedural or major complications judged to be associated with ICUS (uncertain relation or certain relation to ICUS) was compared in different patient groups. The complication rate was higher in patients with unstable angina or acute myocardial infarction (2.1% events) as compared with patients with stable angina pectoris and asymptomatic patients (0.8% and 0.4%, respectively; chi 2 = 10.9, P < .01). These complications were also more frequent in patients undergoing interventions (1.9%) as compared with transplant and nontransplant patients undergoing diagnostic ICUS imaging (0% and 0.6%, respectively; chi 2 = 13.5, P < .001). Adverse events were few, and no association was detected between these events and the size or type of ICUS catheter used. CONCLUSIONS: ICUS is associated with (but not necessarily the direct cause of) a minor acute clinical risk. Vessel spasm is the most frequent event occurring during ICUS. Other complications predominantly occur in patients with acute coronary syndromes and during guidance for intervention.

Adult↗

Contribution of endothelium-derived nitric oxide to coronary arterial distensibility: an in vivo two-dimensional intravascular ultrasound study.

Reduced epicardial coronary arterial distensibility associated with early atherosclerosis may be mediated in part by reduced nitric oxide (NO) release. To directly assess the contribution of endogenous NO to coronary arterial distensibility, we examined the effect of intracoronary N omega nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthase, and L-arginine, its natural substrate, on the circumflex artery in seven anesthetized dogs. We also used intracoronary acetylcholine to examine the effect of pharmacologically induced NO release on coronary distensibility. Electrocardiographically gated measurements of epicardial coronary lumen area were made by a blinded observer from images obtained with a 4.3F, 30 MHz intravascular ultrasound catheter. Aortic root pressure was continuously monitored, and neither systemic arterial pressure nor pulse pressure changed significantly with intracoronary drug administration. Change in lumen area (delta LA) from end systole to end diastole was measured, and an arterial distensibility index was calculated. Delta LA increased with acetylcholine from 8.2% +/- 0.5% at baseline to 16.3% +/- 2.8% (10(-6) mol/L; p < 0.001), with increases in both end-systolic and end-diastolic lumen area and decreased delta LA to 3.1% +/- 1.3% (p < 0.01). Lumen area and delta LA were both restored to baseline by L-arginine (10(-4)). The calculated distensibility index of the epicardial coronary artery was enhanced by acetylcholine, reduced below baseline by L-NAME, and restored to baseline by L-arginine.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗

Mechanisms of estrogen-induced vasodilation: in vivo studies in canine coronary conductance and resistance arteries.

OBJECTIVES: We sought to examine the immediate vasodilator effect of intracoronary estrogen on epicardial and resistance coronary arteries in 19 dogs. BACKGROUND: Although estrogen reportedly dilates coronary arteries in vitro, the site and mechanisms of its action have not been fully defined in vivo. METHODS: Epicardial coronary artery dimensions and coronary flow velocity were assessed using simultaneous intracoronary two-dimensional and Doppler ultrasound. RESULTS: Estrogen (0.1 and 1 mumol/liter) induced a significant increase in coronary cross-sectional area, flow velocity and volumetric blood flow. Estrogen-induced vasodilation was not influenced either by pretreatment with N omega-nitro-L-arginine methyl ester (L-NAME) (100 mumol/liter intracoronary), indomethacin (5 mg/kg body weight intravenously), propranolol (0.75 mg/kg intravenously) or the classic estrogen receptor antagonist ICI 182,780 (10 mumol/liter). Balloon denudation of the endothelium did not attenuate estrogen-induced epicardial vasodilation. Pretreatment with glibenclamide (10 mumol/liter) attenuated estrogen-induced vasodilation only in epicardial arteries, as did verapamil (0.1 mumol/liter). Estrogen had no effect on a phenylephrine dose-response curve in either epicardial coronary arteries or the microcirculation. CONCLUSIONS: Acute estrogen-induced dilation in canine coronary arteries is endothelium independent and is not mediated by the classic intracellular estrogen receptor but through non-genomic mechanisms, presumably at the membrane level, which in epicardial arteries may include effects on adenosine triphosphate-sensitive potassium or calcium channels, or both.

Analysis of Variance↗

Identification of patent foramen ovale permitting paradoxic embolism.

OBJECTIVES: We sought to analyze the morphologic and functional characteristics of the patent foramen ovale in patients with different clinical likelihoods for paradoxic embolism. BACKGROUND: The incidence of patent foramen ovale is increased in patients with otherwise unexplained arterial ischemic events. Because signs of venous thrombosis are absent in most patients, the diagnosis of paradoxic embolism is often questioned, even when patent foramen ovale is the only potential explanation for the ischemic event. METHODS: Seventy-eight patients with a patent foramen ovale detected by contrast transesophageal echocardiography were studied: 21 patients with an otherwise unexplained arterial ischemic event and clinical evidence implying paradoxic embolism (group I), 30 patients with an unexplained ischemic event but no clinical evidence for paradoxic embolism (group II) and 27 patients without an ischemic event (group III). RESULTS: During transesophageal contrast echocardiography, patients in group I had more severe right to left shunting (mean +/- SD 52 +/- 16% of the left atrial area filled with contrast medium) and a wider opening of the patent foramen ovale (7.1 +/- 3.6-mm separation between the septum primum and the septum secundum) than did patients in group II (35 +/- 15% and 4.4 +/- 3.2 mm, respectively, p < 0.001) or group III (23 +/- 12% and 3.0 +/- 2.0 mm, respectively, p < 0.001). The incidence of atrial septal aneurysm was similar in the three groups. Severe contrast shunting (> or = 50% of the left atrial area filled with contrast medium) and wide opening of the patent foramen ovale (> or = 5-mm separation) revealed a high sensitivity (71% and 86%, respectively) and high specificity (86% and 96%, respectively) for identification of group I patients. CONCLUSIONS: Right to left contrast shunting is more severe and opening of the patent foramen ovale is larger in patients with ischemic arterial events considered to be due to paradoxic embolism. In patients with a patent foramen ovale as the only potential cause for ischemic events and no signs of venous thrombosis, morphologic and functional variables assessed by transesophageal echocardiography may be helpful in estimating the likelihood of paradoxic embolism.

Adult↗

Lumen and plaque shape in atherosclerotic coronary arteries assessed by in vivo intracoronary ultrasound.

Current knowledge of lumen and plaque shape of atherosclerotic coronary vessels is derived from in vitro examination of coronary vessels. The in vivo plaque and lumen shape was studied by intracoronary ultrasound (ICUS) imaging in 82 patients with coronary artery disease and the images were analyzed by computerized morphometry. In 386 of the 638 cross sections (61%) with atherosclerotic plaque, nondiseased wall (intima thickness < 200 microns) was present in the ICUS image; in 440 sections (69%), the plaque was located eccentrically in the vessel. Although the extent of nondiseased wall segment and eccentricity decreased with plaque burden, 42% of cross sections with plaque stenosis > 60% had residual nondiseased wall, and 40% of these cross sections showed eccentric plaque. A circular or near-circular lumen (ratio of long/short diameter < 1.1) was found in 252 cross sections (39%), an elliptical lumen in 370 (58%), and a "D"-shaped lumen in 16 cross sections (3%); slit- or star-like lumen shapes were not detected. The ratio of long/short diameter was lower in the 555 noncalcified (1.10 +/- 0.08) than in the 83 calcified cross sections (1.15 +/- 0.08; p < 0.001). Radiographic lumen area measurements were simulated in ellipse models based on the long and short lumen axes measured in the ICUS images. Assuming a single radiographic view, maximal over- or underestimation of up to 40% compared with the true vessel lumen is possible. Errors in lumen area measurements increased with plaque area stenosis, reflecting the more elliptical lumen shape in advanced coronary disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Angina Pectoris↗

Contrast-enhanced intravascular ultrasound: validation of a new technique for delineation of the vessel wall boundary.

OBJECTIVES: We evaluated a new technique for delineation of the vessel wall surface during intravascular ultrasound imaging using echogenic contrast agents. BACKGROUND: Intravascular ultrasound is used for detection of complex vessel wall structures after catheter-based interventions; however, differentiation between the lumen and these wall structures can be difficult. METHODS: In 12 anesthetized dogs, intracoronary ultrasound was performed during intracoronary bolus injection (3 and 6 ml) of different contrast agents (hand-agitated saline solution, standard iohexol, sonicated iohexol, hand-agitated iohexol, SHU 454, SHU 508). Contrast intensity was quantified by videodensitometry, and contrast homogeneity was assessed qualitatively (grade 0 to 3). RESULTS: Peak contrast intensities for SHU 454 and SHU 508 (mean [+/- SD] 48 +/- 9 and 36 +/- 6 U, respectively) were higher compared with standard, sonicated or agitated iohexol (16 +/- 3, 28 +/- 7 and 20 +/- 3 U, respectively) or with agitated saline solution (17 +/- 4 U); intensities were higher for 6 ml compared with that for 3 ml. Contrast homogeneity was higher for SHU 508 (mean [+/- SD] 3.0 +/- 0) and SHU 454 (2.7 +/- 0.5) compared with the other agents (standard iohexol 1.2 +/- 0.4, sonicated iohexol 2.0 +/- 0.5, agitated iohexol 1.8 +/- 0.6, agitated saline solution 1.0 +/- 0.4). Exact delineation of the vessel wall surface was possible in 100% of SHU 508 and in 88% of SHU 454 injections compared with 13% of agitated iohexol and 8% of sonicated iohexol injections. Accurate surface delineation was never achieved with standard iohexol or agitated saline solution. Shadowing of parts of the vessel wall by contrast material occurred at peak intensity of 75% of SHU 508 and 46% of SHU 454 injections but not with the other agents. No adverse physiologic reactions were noted, except for transient negative inotropic effects after 6 ml of SHU 508. CONCLUSIONS: This preliminary study shows that delineation of the vessel wall boundary using echogenic contrast agents during intravascular ultrasound is safe and feasible. Because of higher contrast intensity and homogeneity, SHU 454 and SHU 508 are superior to other agents.

Animals↗

Intracoronary ultrasound imaging: intraobserver and interobserver variability of morphometric measurements.

Measurements of lumen and plaque dimensions by intracoronary ultrasound imaging are useful in assessing effects of intracoronary interventions and in quantifying plaque burden in transplant patients or during regression trials. However, these measurements are affected by inter- and intraobserver variability. In 87 patients, 120 intracoronary ultrasound images were obtained with a 4.3F, 30 MHz catheter. Morphometric measurements were performed two times by three independent observers using computerized planimetry. Intraobserver and interobserver agreement for qualitative parameters (presence of atherosclerotic plaque, calcified plaque, and residual nondiseased wall) was high (> 87%). For quantitative parameters measured directly in the images (lumen area, minimal and maximal lumen diameters, area within the internal elastic lamina, arc of calcium plaque) interobserver and intraobserver correlation between measurements was high (correlation coefficient r > 0.90) and differences between measurements were low (mean differences < 10%; SD < 20%). Measurement of the arc of nondiseased wall showed less interobserver correlation (r = 0.76 to 0.91), but percentages of difference between the measurements were low. Parameters derived from directly measured variables (plaque area, area stenosis, thickness, and eccentricity) showed slightly higher variability (correlations between measurements r = 0.78 to 0.91). SD for percentages of difference ranged between 20% and 30% (plaque area, area stenosis, and thickness) and systematic deviation between measurements (mean differences > 10%) occurred for plaque area. Thus most qualitative and quantitative measurements of lumen and plaque dimensions performed in intracoronary ultrasound images have low in intraobserver and interobserver variability; derived parameters may have slightly higher variability. Variability of morphometric measurements has to be considered, especially when serial ultrasound measurements are compared.

Adult↗

Detection of intralesional calcium by intracoronary ultrasound depends on the histologic pattern.

This study was designed to examine the accuracy of intravascular ultrasound in detecting different histologic types of calcium pattern in human coronary artery atherosclerotic lesions. Previous studies have shown that calcium deposits in atherosclerotic lesions may occur in various forms and that intravascular ultrasound is a sensitive technique to detect calcium in atherosclerotic lesions. However, there has been no distinction between varying image representations of calcium and different histologic patterns of intralesional calcific deposits. Calcific lesions have an important clinical impact on the outcome of intracoronary transcatheter therapy, and the varying types of calcium may also play a role in the guidance of intracoronary interventions. Fifty fresh coronary vessel segments were studied by intracoronary ultrasound imaging and the images compared with the corresponding histologic sections. With intracoronary ultrasound imaging, calcium was defined as bright echo with corresponding sharp edged shadowing in the distal field. Three different histologic types of calcification were defined, and the sensitivity and specificity of the detection by intravascular ultrasound were determined for each type. Dense calcified plaques (type 1) were found 18 cases, microcalcification (small flecks of calcium) with single calcium fleck size < or = 0.05 mm (type 2) in 12 cases, and combination of calcified plaque surrounded by small calcium flecks (type 3) in 3 cases. In 17 (34%) coronary vessel segments, histologic analyses detected no calcium. Intracoronary ultrasound correctly detected 16 (89%) of 18 cases of type 1 calcification, 2 (17%) of 12 type 2, and all 3 (100%) type 3. Sensitivity for detection of type 1 and 3 calcification was 90%, with specificity of 100%.(ABSTRACT TRUNCATED AT 250 WORDS)

Calcium↗

[The form of atherosclerotic coronary plaques: pathoanatomic concepts and new insights using intravascular ultrasound].

In addition to the degree of vessel obstruction and to the composition of the atheroma, the geometric shape of the plaque--in particular the presence of non-diseased wall segments--is an important factor in the pathophysiology and therapy of coronary heart disease. The relevance of the plaque shape has been emphasized by pathoanatomic studies in the late 1970s. The in vivo assessment of the plaque shape using coronary angiography has major limitations: The lumen silhouette obtained by angiography does not accurately reflect the histologic extent of the plaque due to compensatory vessel enlargement, atrophy of the media, and diffuse plaque accumulation. In contrast, intravascular ultrasound (IVUS) allows direct, cross-sectional visualization of the plaque. Although this method has a small, but definite acute risk, it provides the first technique for in vivo assessment of the extent and shape of coronary plaque. In agreement with prior pathoanatomic investigations, IVUS studies have confirmed that the majority of advanced coronary plaques are located eccentrically in the vessel and that non-diseased wall segments are often present in these lesions. Using IVUS imaging, it has also been proven that in vivo relaxation of advanced coronary stenoses by vasodilatory drugs is mainly based on expansion of the non-diseased wall segment. IVUS studies have also shown that the presence of non-diseased wall segments may be important for the effect of intracoronary interventions: Balloon angioplasty of eccentric coronary lesions often causes dilatation of the non-diseased wall segments; immediate and chronic elastic recoil of these vessel segments may diminish the lumen gain from this procedure. During directional coronary atherectomy IVUS imaging of the exact location and shape of the plaque may limit subintimal tissue retrieval and thereby also reduce restenosis.

Angioplasty, Balloon, Coronary↗

Quantitation of soluble HLA-DR antigens in human serum and other body fluids.

The existence of soluble forms of MHC class II molecules is well established. To quantify soluble HLA-DR antigens (sHLA-DR) in human serum and other body fluids, we developed an enzyme immunoassay using two non-overlapping HLA-DR-specific monoclonal antibodies (RoDR, BL-la/5) and an immunoaffinity chromatography-purified sHLA-DR standard. In serum of healthy individuals, sHLA-DR levels were found in the range between 0.6 and 3 ng/ml (median 0.85 ng/ml) whereas EDTA plasma samples showed concentrations about 20 times higher (median 21 ng/ml). In tears, saliva, sweat, urine, amniotic fluid, cerebrospinal fluid, and bronchoalveolar lavage, sHLA-DR could also be detected. No association was found between sHLA-DR serum levels and distinct HLA specificities. In the sera of patients with autoimmune diseases, slightly enhanced sHLA-DR values were found (juvenile rheumatoid arthritis: median 2.0 ng/ml, lupus erythematosus: 1.5 ng/ml, diabetes mellitus: 2.1 ng/ml).

Amniotic Fluid↗

Comparison of transthoracic and transesophageal echocardiography for detection of abnormalities of prosthetic and bioprosthetic valves in the mitral and aortic positions.

Two-dimensional echocardiography is the diagnostic procedure of choice for evaluation of prosthetic valve abnormalities. However, transthoracic echocardiography (TTE) may be limited owing to acoustic shadowing and poor acoustic windows. Some of these limitations may be overcome by transesophageal echocardiography (TEE). One hundred twenty-six patients with 148 prosthetic valves (113 bioprostheses and 35 mechanical devices) were studied by M-mode and 2-dimensional TTE and TEE. Prosthetic valve morphology was confirmed by surgery or autopsy in all cases; 124 prostheses were classified as diseased (33 endocarditis, 8 thrombi, and 83 degeneration defined as leaflet thickening > 3 mm with restricted motion) and 24 as normal. Prosthetic valve endocarditis and thrombi were correctly identified by TTE in 12 of 33 (36%) and 1 of 8 (13%) prostheses, respectively, but could be diagnosed by TEE in 27 of 33 (82%; p < 0.001) and 8 of 8 (100%; p < 0.01), respectively. Compared with TTE, TEE had a higher sensitivity for morphologic prosthetic valve abnormalities in patients with either bioprostheses (88 [87%] vs 66 [65%] of 101 prostheses; p < 0.01) or mechanical devices (19 [83%] vs 5 [22%] of 23 prostheses; p < 0.01) and in patients with a prosthesis in either the aortic (49 [77%] vs 32 [50%] of 64; p < 0.01) or mitral (58 [97%] vs 39 [65%] of 60; p < 0.001) position. Overall, sensitivity and specificity were 57 and 63%, respectively, for TTE, and 86 and 88%, respectively, for TEE.(ABSTRACT TRUNCATED AT 250 WORDS)

Aortic Valve↗

Effect of medical and surgical therapy on aortic dissection evaluated by transesophageal echocardiography. Implications for prognosis and therapy. The European Cooperative Study Group on Echocardiography.

BACKGROUND: Aortic dissection still has a poor prognosis despite progress in therapy. Therefore, this prospective follow-up study was designed to determine whether the degree of communication between true and false lumen in relation to the type of dissection, analyzed by transesophageal echocardiography, influences the risk after initiation of medical or surgical therapy. METHODS AND RESULTS: In eight centers, 168 patients (124 men and 44 women) of age range of 23-84 years with proven aortic dissection were examined by transesophageal echocardiography in the acute phase, after start of medical and/or surgical therapy, and during follow-up (0-65 months; mean, 10 months). Analyses were performed prospectively according to a detailed study protocol. Patients were subdivided by transesophageal echocardiography according to a modified DeBakey classification. Type I aortic dissection was found in 35%, type II aortic dissection in 17%, and type III aortic dissection in 48%. Preoperative mortality was 3%, 7%, and 2%, and survival rates were 52%, 69%, and 70%, respectively. Type III aortic dissection could be subdivided into those with communication and antegrade dissection (ca) (50%), with communication and retrograde dissection limited to the descending aorta (cr desc) (10%), with dissection extended to the aortic arch and ascending aorta (cr asc) (27%), and with noncommunicating (nc) aortic dissection (13%). An open false lumen with no thrombus formation was present in types I, II, III ca and III cr asc aortic dissection in 17%, 21%, 39%, and 27% respectively, although it was most pronounced in types III nc and III cr desc (75% and 78%). During follow-up in patients who survived, thrombus was demonstrated in the false lumen in 80% of type I aortic dissection and 81% of types III ca and III cr asc. Open false lumen was seen in type II aortic dissection in 18%. Spontaneous healing was found in 4% with type II and 4% with type III aortic dissection (mainly in patients with type III nc aortic dissection). Patients with fluid extravasation, pleural effusion, pericardial tamponade, and periaortic effusion as well as mediastinal hematoma had a mortality of 52%. Reoperations were necessary in 12-29%, with the highest rate in patients with type III ca aortic dissection. Survival for patients with types III nc and III cr desc aortic dissection was higher than those with types I, II, III ca, and III cr asc. CONCLUSIONS: Preoperative mortality appears to be reduced by transesophageal echocardiography, allowing rapid initiation of treatment. Intraoperative and postoperative mortality in aortic dissection remains high. Risk factors are fluid extravasation and an open false lumen with high communication. Thrombus formation in the false lumen can be regarded as a good prognostic sign. Surgery appears to be only a first step in the treatment of aortic dissection. Second surgery or closure of entry sites based on intraoperative echocardiography may be considered to induce thrombus formation and reduce aortic wall stress.

Adult↗