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J Laas

Publications and source records attributed to J Laas.

At least 37 records · Page 2Linked to original sources
PubMed1993

Three-dimensional vascular imaging--an additional diagnostic tool.

Angiography is still the standard for imaging of vascular structures. However, since the number of projections is limited, complex pathoanatomy may not be sufficiently visible. This study presents two patients in whom 3D reconstruction from Spiral CT data revealed combined vascular lesions undisclosed by angiography. In one case the combination of coarctation and chronic dissection type B, in another the combination of two aneurysms of the celiac trunk in series was disclosed. We conclude that 3D reconstruction can be a valuable asset in the diagnosis of complex vascular pathoanatomy.

Adult↗
PubMed1993

A case of coronary stenosis developing after successful aortic valve repair in Cogan's syndrome.

Cogan's syndrome has been described as entity of progressive deafness and interstitial keratitis with variable cardiovascular involvement leading to aortic insufficiency or orificial stenosis of coronary or aortic arch vessels. So far, aortic valve replacement either with mechanical or biological prosthesis was favored for correction of the valvular lesion. A patient with primary successful aortic valve repair followed by coronary revascularization for left coronary ostial stenosis occurring after the first operation is presented.

Adult↗
PubMed1993

[Surgical aspects of fulminant pulmonary embolism].

Fulminant pulmonary embolism associated with cardiac arrest has an extremely high mortality. The feasibility of pulmonary embolectomy initiated during resuscitation is still under discussion. Between January 1975 and October 1992, embolectomy was performed in 34 patients, 21 to 79 years of age. Diagnosis was established primarily by indirect parameters (medical history, ECG, blood gas analyses, Swan-Ganz catheter in 22 cases). Only in 12 instances, imaging techniques as angiography, ventilation perfusion mismatch, and transesophageal echocardiography were performed. Fifteen patients did not require resuscitation (group A); 6 had to be resuscitated and underwent surgery after reestablishing circulation with catecholamines (group B); 13 patients were connected to extracorporeal circulation during continuous cardiopulmonary resuscitation (30 to 210 minutes) (group C). Embolectomy was performed using extracorporeal circulation with the heart beating (n = 8), or fibrillating (n = 15), or using cardioplegia (n = 11). Twenty-two patients received a caval clip or ligature at the end of the procedure. Fifteen patients (44%) died early postoperatively. The mortality rates for groups A, B, and C were 33%, 66% and 46%, respectively. Nine patients died of right heart failure, 4 of brain death, and 2 of septical complications. Of the surviving patients, only one had ischemic brain damage. In two cases a recurrent pulmonary embolism occurred after a follow-up of 16 years (mean follow-up 4.9 years). We conclude, that even with subtotal obstruction of the pulmonary artery, effective cardiopulmonary resuscitation with maintenance of uncompromised brain function is possible. In emergency situations, the decision to operate may be based only on clinical features without imaging diagnostic procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Advances in aortic arch surgery.

From 1980 to January 1991, 130 patients (89 men and 41 women, aged 22 to 76 years; mean age, 52 years) underwent 133 interventions on the aortic arch. Aneurysm was diagnosed in 57 patients, whereas 29 had chronic and 44 acute aortic dissection. In 67 instances a partial and in 35 instances a total arch replacement was performed. The distal arch was approached through a left thoracotomy in 14 patients. Local interventions (n = 17) included surgical reconstruction and glue procedures. Additionally, 55 patients required aortic valve replacement, preferably with composite grafts (n = 46), whereas the valve was reconstructed in 14. Procedures were performed using hypothermia (nasopharyngeal temperature, 11 degrees to 25 degrees C) and circulatory arrest (mean time, 27 minutes). Early mortality was 13.9% at the first operation on the aortic arch. Early deaths included 7 of 57 patients with aortic aneurysm (12.3%), 2 of 29 patients with chronic dissection (6.9%), and 9 of 44 patients with acute dissection (20.5%). Neurological (n = 6) and cardiac events (n = 5) were the most common causes of early death. Since 1987, 7 of 88 patients have died for an overall mortality of 8.0%. With growing experience, proper indication, and adequate operative strategy including the use of circulatory arrest in hypothermia, operation on the aortic arch can be performed with an acceptable risk.

Adult↗
PubMed1992

[Artificial intravascular oxygenation (IVOX). Application to the treatment of postoperative respiratory failure].

Very recently, the concept of artificial intracorporeal oxygenation of blood for patients suffering from respiratory failure has been introduced into clinical practice through development of a totally implantable intravascular oxygenator (IVOX). We report on the use of such a device in a patient who developed severe respiratory insufficiency secondary to prolonged hypovolaemic shock and pneumonia following successful repair of a ruptured abdominal aortic aneurysm in September, 1990. Postoperatively, severe hypoxaemia occurred (AaDO2 548-602 torr) despite extensive mechanical ventilatory support. There was no obvious chance to overcome this situation by conventional therapeutic measures and the decision was made to institute IVOX therapy. Hypoxaemia was resolved immediately and both FiO2 and tidal volume could be reduced within hours. The patient's respiratory condition continued to improve over the next days leading to termination of IVOX therapy after 71 hours. However, the necessity of long-term ventilatory support secondary to recurrent pneumonia and sepsis, multiple abdominal reoperations for ischemic colitis and retroperitoneal abscess prolonged his recovery. He was discharged from the hospital after four months and is alive and well now 14 months after his operation. He is the first long-term survivor after IVOX therapy in Europe. IVOX may be successfully used in selected patients while the indications and it's potential role in the therapy of severe respiratory failure still need to be defined.

Humans↗
PubMed1992

Open-heart surgery in patients requiring chronic hemodialysis.

The management and outcome of open-heart surgery in 31 patients requiring chronic hemodialysis because of end-stage renal failure are reviewed. The reasons for surgery were coronary artery disease (20 cases), mitral valvulopathy (5, including 3 with tricuspid insufficiency), aortic valvulopathy (5, including 2 with coronary artery disease) and perforation of an aortic aneurysm into the left upper lung lobe. Surgery was elective in all but the last case. Apart from double venous cannulation to avoid potassium overload after cardioplegia, and hemofiltration in the extracorporeal circulation permitting removal of 1,500-2,000 ml fluid during bypass, procedure was routine. Postoperatively fluids were restricted and serum potassium levels were not allowed to exceed the known preoperative maximum. Four patients required catecholamine support for 3-10 hours. Thirty were weaned from the respirator after 8-41 (mean 16) hours. The one perioperative death was due to complications associated with post-bypass administration of protamine. Dialysis was restarted 20-69 (mean 32) hours postoperatively. With appropriate management of fluid balance and potassium, open-heart surgery in dialysis-dependent patients need not carry heightened risk.

Adult↗
PubMed1992

[Surgical aspects of acute aortic dissection].

This paper highlights some of the surgical aspects of acute aortic dissections such as: emergency diagnosis, indications for surgery, reconstructive operative techniques, malperfusion phenomena and necessity for follow-up. Aortic dissection is caused by an intimal tear, called the "entry", and subsequent splitting of the media by the stream of blood. Two lumina are thus created, which may communicate through "re-entries". As this creates severe weakness of the aortic wall, rupture and/or dilatation are the imminent dangers of acute aortic dissection. Acute aortic dissection type A, by definition involving the ascending aorta (Figures 1 and 2), is an absolute indication for emergency surgical treatment, because its natural history shows an extremely poor outcome (Figure 3). Due to impending (intrapericardial) aortic rupture, it may be necessary to limit diagnostic procedures to a minimum. Transesophageal echocardiography is the method of choice for establishing a quick, precise and reliable diagnosis (Figure 4). In stable patients, computed tomography gives additional information about aortic diameters or sites of extrapericardial perforation. Digital subtraction angiography (DSA) shows perfusion of the lumina and dependent organs. The surgical strategy in acute aortic dissection type A aims at replacement of the ascending aorta. Reconstructive techniques have to be considered, especially in aortic valve regurgitation without annuloectasia (Figures 5 and 6). In recent times, the use of GRF tissue glue has reduced the need for teflon felt. Involvement of the aortic arch should be treated aggressively up to the point of total arch replacement in deep hypothermic circulatory arrest as part of the primary procedure (Figure 7). Malperfusion phenomena of aortic branches remain risk-factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗
PubMed1992

Long-term follow-up after separate replacement of the aortic valve and ascending aorta.

Between May 1974 and November 1991, 28 patients underwent a separate replacement of the aortic valve and the ascending aorta (20 male, eight female; 32 to 71 years old, x = 52 years). 23 patients were operated for ascending aortic aneurysm, three for chronic and two for acute aortic dissection type A. 17/18 patients living at the beginning of this study were re-investigated after a mean follow-up interval of 8.5 years postoperatively with DSA, thoraco-abdominal CT and echocardiography. 1/8 biological aortic valves and 1/20 mechanical valves had to be replaced (four years and two months postoperatively) for valve degeneration and paravalvular leakage respectively. Three patients developed a sinus of Valsalva aneurysm and were reoperated five, 9.2 and 9.3 years after primary repair. In all three patients histological signs of idiopathic degenerative media disease of the aorta were found. Two other patients presented with a perfused perigraft channel and therefore had to be reoperated. Patients with chronic aortic dissection type A and/or ascending aortic aneurysms presenting clinical or intraoperative signs of degenerative media disease of the aorta should undergo composite graft replacement to preclude formation of sinus Valsalva aneurysms.

Adult↗
PubMed1992

[Progress in surgery of the aortic arch].

We summarize our experience out of 133 operations involving the aortic arch which were performed in 130 patients throughout the last 13 years. Aortic pathology was aneurysmal disease in 57 cases, acute aortic dissection in 44, and chronic aortic dissection in 29 patients. Operative strategies included partial replacement or repair of the aortic arch in 80 cases and subtotal or total replacement of the transverse arch in 53 patients. In 19 cases presenting with aneurysms of the descending thoracic aorta, implantation of an elephant trunk prothesis was performed simultaneously. The operations were performed during circulatory arrest (10-64 min, mean: 27 min) and in deep hypothermia (nasopharyngeal temperature: 11-25 degrees C). Recently, two modifications of the technique were introduced: First, the site of arterial inflow cannulation is changed by intubating the prothesis directly during reperfusion providing antegrade perfusion. Second, in patients with acute aortic dissection, the false lumen of the aortic root and arch is filled with resorcinformol glue and the layers are readapted by this means after anatomical reconstruction. Overall, early mortality was 14.3% and was much higher in acute dissection (22.7%) when compared to chronic dissection (6.9%, p = 0.110). A total of 24 reoperations were necessary in 16 patients of this group with subsequent replacement of the descending thoracic aorta being most frequently performed (n = 14). Actuarial survival after 5 years was not significantly different between the groups (69.1%) but showed a progressive decline for patients with aneurysms and chronic dissection (11 late deaths) while no late deaths occurred in acute dissections.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Improvement in the diagnosis of abscesses associated with endocarditis by transesophageal echocardiography.

BACKGROUND: Echocardiography is recognized as the method of choice for the noninvasive detection of valvular vegetations in patients with infective endocarditis, with transesophageal echocardiography being more accurate than transthoracic echocardiography. The diagnosis of associated abscesses by transthoracic echocardiography is difficult or even impossible in many cases, however, and it is not known whether transesophageal echocardiography is any better. METHODS: To determine the value of transesophageal echocardiography in the detection of abscesses associated with endocarditis, we studied prospectively by two-dimensional transthoracic and transesophageal echocardiography 118 consecutive patients with infective endocarditis of 137 native or prosthetic valves that was documented during surgery or at autopsy. RESULTS: During surgery or at autopsy, 44 patients (37.3 percent) had a total of 46 definite regions of abscess. Abscesses were more frequent in aortic-valve endocarditis than in infections of other valves, and the infecting organism was more often staphylococcus (52.3 percent of cases) in patients with abscesses than in those without abscesses (16.2 percent). The hospital mortality rate was 22.7 percent in patients with abscesses, as compared with 13.5 percent in patients without abscesses. Whereas transthoracic echocardiography identified only 13 of the 46 areas of abscess, the transesophageal approach allowed the detection of 40 regions (P less than 0.001). Sensitivity and specificity for the detection of abscesses associated with endocarditis were 28.3 and 98.6 percent, respectively, for transthoracic echocardiography and 87.0 and 94.6 percent for transesophageal echocardiography; positive and negative predictive values were 92.9 and 68.9 percent, respectively, for the transthoracic approach and 90.9 and 92.1 percent for the transesophageal approach. Variation between observers was 3.4 percent for transthoracic and 4.2 percent for transesophageal echocardiography. CONCLUSIONS: The data indicate that transesophageal echocardiography leads to a significant improvement in the diagnosis of abscesses associated with endocarditis. The technique facilitates the identification of patients with endocarditis who have an increased risk of death and permits earlier treatment.

Abscess↗
PubMed1991

Fulminant pulmonary embolism: symptoms, diagnostics, operative technique, and results.

Fulminant pulmonary embolism associated with cardiac arrest has an extremely high mortality. The feasibility of pulmonary embolectomy initiated during resuscitation is still under discussion. Between January 1975 and January 1991, pulmonary embolectomy was performed in 27 patients, 21 to 79 years old. The diagnosis was established primarily by clinical findings in 18 patients, by angiography and ventilation-perfusion mismatch in 4 patients, and by transesophageal echocardiography in 1 patient seen recently. Eleven patients did not require resuscitation (group 1); 5 patients had to be resuscitated and underwent operation after circulation was reestablished without need of further cardiac massage (group 2); and 11 patients were connected to extracorporeal circulation devices during cardiopulmonary resuscitation (30 to 210 minutes) (group 3). Embolectomy was performed using extracorporeal circulation with the heart beating (n = 2) or fibrillating (n = 15) or using cardioplegia (n = 10). Fifteen patients received a caval clip or ligature at the end of the procedure. Twelve patients died early postoperatively; the mortality rates were 36%, 60%, and 45% for groups 1, 2, and 3, respectively. Eight patients died of right heart failure, and 2 patients each died of brain death and sepsis. Of the surviving patients, only 1 showed ischemic brain damage. Mean stay in the intensive care unit was 5.1, 7.0, and 9.75 days for groups 1, 2, and 3, respectively. There were no recurrent embolisms during the 15-year follow-up (mean follow-up, 4.6 years). This experience demonstrates that even with subtotal obstruction of the pulmonary arteries, effective cardiopulmonary resuscitation with maintenance of uncompromised brain function is possible.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiopulmonary Resuscitation↗
PubMed1991

Tumor-related obstruction of the inferior vena cava extending into the right heart--a plea for surgery in deep hypothermic circulatory arrest.

This study reviews eight patients, 39-63 years old, with tumor-related obstruction of the inferior vena cava (IVC) extending into the right atrium (n = 5) and ventricle (n = 3). Five patients suffered from renal cell carcinoma, 3 from sarcomatous disease. The general approach was a median sternotomy and laparotomy with hypothermic circulatory arrest (17.0-20.5 degrees C; 23-46 min) in six patients, while in two patients, the IVC was clamped sequentially under moderate hypothermia and extracorporeal circulation. Four patients had tumor infiltration of the IVC necessitating partial caval resection. In three, the IVC was reconstructed by fabric patches or tubular prothesis. In one patient, the continuity of the IVC was interrupted permanently. Three patients underwent nephrectomy during the same procedure, two before and one after IVC disobliteration. In one patient each, pulmonary embolectomy and intrahepatic IVC stenting were performed. Two patients died early, one due to uncontrollable hemorrhage the other due to non-cardiogenic pulmonary edema. Six patients were discharged in good physical condition and are still alive at a mean follow-up of 24 months. Five patients have since remained free of recurrence, one patient underwent three further surgical interventions for bone metastases. We feel that IVC desobliteration is feasible in selected cases with extended tumor-related obstruction with an acceptable early risk and late outcome.

Adult↗
PubMed1991

[Risk factors for early fatality of ruptured abdominal aortic aneurysms].

Early mortality (EM) following surgery for ruptured abdominal aneurysm continues to be extremely high. In the literature EM still ranges between 30 and 85%, despite improvement of surgical intervention and perioperative management in the recent years. Numerous studies investigate intra- und postoperative parameters, but little is known about preoperative transportation circumstances and the clinical condition prior to intervention. The transportation system at our clinic allowed a complete retrospective assessment of these parameters which were included into the evaluation of the risk factor analysis of the study. From 1974 to 1986 142 patients (131 male, 11 female, mean age: 68.8 years [46-89 years]) were operated on ruptured abdominal aneurysms. Time intervals prior to admission and surgical intervention as well as perioperative data were retrospectively assessed. The patients were divided in: deceased (D) within 30 days and survivors (S). Late survival was assessed either by letter or telephone interview. Age and sex showed no influence on the early mortality. Transportation time and time interval: admission/operation were similar in both groups. The shockindex showed a significant difference. D: 1.1 +/- 0.27; S: 0.8 +/- 0.16. Anuria was seen in 66% of the diseased and 26% of the surviving patients. If free perforation was detected 20 of 30 patients died. The total amount of transfusion differed significantly: D: 6.8 +/- 2.51; S:3.9 +/- 2.01. If diaphragmal X-clamp was necessary 7 of 8 patients died. The necessity of catecholamine support postoperatively was 64% for deceased patients. Dialysis was necessary in 77.8% of the deceased patients. 84% of D developed an ileus and 67% of D developed a pneumonia.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1991

Management of thoracoabdominal malperfusion in aortic dissection.

Malperfusion of the thoracoabdominal aorta or its branches is a common complication of aortic dissection, often with a fatal outcome. Since 1985 we saw thoracoabdominal malperfusion in 13 patients with aortic dissection. During repair of an acute type A aortic dissection, the intimal flap was fenestrated in three cases in the abdominal aorta and one within the superior mesenteric artery. In two cases with acute type B aortic dissection fenestration was performed at the level of the aortic bifurcation, and in one the descending aorta was replaced. Six patients had chronic dilatation of a false lumen without distal reentry, compromising the true lumen, with malperfusion of viscera, kidneys, and lower extremities. Three patients underwent replacement of the descending aorta, two of them subsequent abdominal aortic replacement with revascularization of the kidneys. One patient had thoracoabdominal replacement, and in two an extra-anatomic bypass was implanted. Five patients with acute dissection died: two from sequelae of malperfusion, two of myocardial failure, and one late after stroke. Eight patients are alive 1 month to 5 years after operation. In acute aortic dissection fenestration of the intimal flap may relieve thoracoabdominal malperfusion. In chronic aortic dissection, pseudocoarctation is most likely to occur at the diaphragmatic hiatus. This is treated by replacement of the affected aortic segment. In high-risk patients an extra-anatomic bypass is also feasible.

Aortic Dissection↗
PubMed1991

Surgery extended into the aortic arch in acute type A dissection. Indications, techniques, and results.

From May of 1979 to September of 1990, 106 patients underwent emergency surgery for acute type A aortic dissection. In 29 patients (27.3% of total; mean age, 53 years) surgery was extended into the aortic arch. In 19 cases the proximal entry reached or began beyond the aortic cross-clamping site, which prevented proper reconstruction of the distal aorta. In six cases an aortic perforation was located in the arch. In four others the dissection occurred within a preexistent arch aneurysm. Operative techniques consisted of eight arch reconstructions, 17 proximal arch replacements, and four total arch replacements. Repair was performed during deep hypothermia (mean nasopharyngeal temperature, 17.8 degrees C) and circulatory arrest (mean, 24.2 minutes). Operative mortality was 20.6% (six of 29), dropping to 10.5% (two of 19) during the past 4 years. There were no late deaths in the 23 survivors, with one patient suffering from neurological sequelae. Nineteen underwent either computed tomography and digital subtraction angiography or magnetic resonance imaging without pathological findings in the ascending aorta or arch. In acute type A aortic dissection the site of the intimal tear and/or perforation, as well as preexistent aneurysmatic disease, may require primary aortic arch repair. This can be accomplished during deep hypothermia and circulatory arrest, with acceptable early and satisfactory late results.

Aortic Dissection↗