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J Laas

Publications and source records attributed to J Laas.

At least 55 records · Page 3Linked to original sources
PubMed1991

[Long-term results 10-14 years following implantation of Y-prostheses for arterial occlusive disease].

Between 1973 and 1977 169 patients underwent implantation of bifurcated prostheses for arterial occlusive disease. Perioperative and follow-up data 10-14 years after operation were retrospectively assessed. The angiologic status of living patients was compiled. Impact of following risk factors was investigated with multivariant analysis. Coronary artery disease, hypertension, smoking, diabetes mellitus, Pulmonary disease, renal insufficiency, obesity. Follow-up was 98.8%. Preoperatively over 90% of the patients investigated had been in grade IIb (Fontaine) or worse (33% grade IV). Early mortality was 5.3% (1973 = 15%, 1977 = 5.3%, 1987/1988 = 1.8%) and was mainly related to cardiopulmonary factors. Reoperation was necessary in 69 patients (149 procedures, no mortality, 38 amputations). Late mortality was 75% (120 of 160 patients) and mainly due to cardiac problems. The 10-year-actuarial-survival (37%) was reduced due to following combinations of risk factors: Myocardial infarction/smoking/obesity (n = 41) 17%, diabetes/smoking (n = 36) 17% hypertension/myocardial infarction (n = 24) 8%. Clinical condition of the living patients (n = 40) was: 48% grade I, 28% grade IIa, 18% grade IIb, none grade III, 8% grade IV. Long term results following implantation of bifurcated prostheses for arterial occlusive disease show, that quality of life is consistently improved. Reoperation is necessary in almost half of the patients due to the progressive disease. Late mortality is closely related to the underlying arteriosclerosis. Life expectancy of our patients does not significantly differ from the normal population and is probably a sequelae of the close follow-up.

Adult↗
PubMed1990

Thoracic aortic aneurysms after acute type A aortic dissection: necessity for follow-up.

Between April 1979 and May 1989, 86 patients underwent emergency operation for acute type A aortic dissection. Sixty-four (74.4%) survived. None of the survivors died of late aortic complications. Fifty-eight patients were followed 3 months to 10 years (mean follow-up, 3.2 years) postoperatively with computed tomography and digital subtraction angiography. Dilatation of the distal aorta (diameter size range, 6 to 10.5 cm) developed in 10 patients (17%). Six patients underwent replacement of the descending aorta 1 month to 21 months (mean period, 8.5 months) after aortic dissection repair. Two of them had third-stage thoracoabdominal replacement. In 2 patients, replacement of the descending aorta was scheduled; 1 died before reoperation and 1 refused the procedure. Two patients underwent aortic arch replacement; it is scheduled for another (fourth stage). There were no deaths among the patients having reoperation. The rate of indications for reoperation on the aorta downstream from the original repair 1 month to 6 years 4 months (median time, 9 months) after primary surgical intervention for acute type A aortic dissection was 24% (14 reoperations in 10 of 58 patients). This study underscores the importance of close follow-up of patients having operation for acute type A aortic dissection. Early recognition of progressive downstream aortic pathology permits effective prevention of aortic rupture and timely reoperation.

Adult↗
PubMed1990

[Postoperative diagnosis following separate replacement of an aortic valve and an ascending aorta using IV-DSA and CT].

We performed a follow-up examination by intravenous DSA and dynamic CT of 14 patients with separate replacement of aortic valve and ascending aorta due to an aneurysm or an aortic dissection. In 5 patients, we found an aortic ectasia at the aortic bulb or a perfused "graft inclusion". Both are best demonstrated with dynamic CT. As a result of the study, the operation technique was changed. In the postoperative management of patients with separate replacement of aortic bulb and ascending aorta, careful monitoring by dynamic CT is necessary even in the absence of clinical symptoms.

Adult↗
PubMed1990

[After care and reoperation after primary intervention in chronic type A aortic dissection].

UNLABELLED: Between 4/78 und 9/89 44 patients (pts.) underwent primary repair of CADA. 3 pts. died early postoperatively. 36 pts. were followed-up 3 months to 9.7 years (means = 3.1 years) postoperatively with CT, DSA and echocardiography. 8 pts. underwent 12 aortic reoperations, in 10 cases due to persistent or recurrent aneurysms. CONCLUSIONS: In CADA radical replacement of the Ascending Aorta is advisable to prevent recurrent aneurysms formation. Systematic follow-up facilitates early recognition and repair of progressively chronic or new downstream aortic pathology.

Adult↗
PubMed1990

[Severe thoracic trauma: under what accident and resuscitation conditions can it still be treated?].

Severe thoracic trauma is a major cause of early death following road accident. 569 non-surviving and 112 surviving victims of traffic casualties were documented by the Accident Research Unit of the Clinic of Trauma Surgery, Hannover Medical School from 1973 to 1987. Medical data and measures of rescue were evaluated with a view to way of clinical therapies, lethal outcome and time of death. Primary intubation and chest draining seems to be the most successful initial treatment on the scene and during transport.

Accidents, Traffic↗
PubMed1990

[Embolectomy in fulminant lung embolism and persistent electromechanical uncoupling--a case report and review of the literature].

A 56-year-old patient with deep vein thrombosis shown by phlebography developed a massive pulmonary embolism during perfusion ventilation lung scanning with complete occlusion of the main pulmonary artery branch. 40 minutes after beginning of symptoms the patient suffered from persistent heart failure. Under external heart massage and controlled ventilation a cardio-pulmonary bypass was established after sterniotomy. After manual manipulations to express peripheral emboli pulmonary embolectomy and cava clipping was performed. The patient recovered without neurological damage.

Cardiopulmonary Bypass↗
PubMed1989

The effect of controlled reperfusion in porcine hearts submitted to three hours of cold global ischemia.

At present, many investigations of myocardial function following ischemic insults concentrate on the modalities of reperfusion rather than on the mode of preservation. In this study, we tried to define the effect of reperfusion using warm blood cardioplegia (WBC) after medium-term (3 h) cold global ischemia, as required in cardiac transplantation. Twenty-one porcine hearts were harvested after preservation with cold cardioplegia (St. Thomas Hospital solution) and topical cooling. Normothermic reperfusion with blood was initiated after 3 h of ischemia utilizing a special extracorporeal pump circuit. Twelve hearts served as controls (group A), while substrate-enriched WBC was applied during the initial 20 min of reperfusion in nine hearts (group B). Hearts in both groups were then studied for myocardial function and metabolism under both working and nonworking conditions for a maximum of 180 min. In the nonworking mode, left ventricular dp/dt was significantly higher in group B than in group A at 15 min (2201 +/- 785 mm Hg/sec vs 1515 +/- 732 mm Hg/sec) and at 180 min (1730 +/- 471 mm Hg/sec vs 836 +/- 147 mm Hg/sec; P less than 0.05). After 3 h, lactate production was significantly higher in group A (371 +/- 45 mg/dl) than in group B (108 +/- 44 mg/dl; P less than 0.05). Creatine kinase release into the coronary sinus was also significantly elevated in group A at 15 min (2807 +/- 1478 IU/l vs 1148 +/- 1272 IU/l; P less than 0.05). Similarly, the hemodynamic data obtained under working conditions in group B were superior to those in group A.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Intravenous DSA and dynamic computed tomography for postoperative follow-up of type A aortic dissections.

We undertook a direct comparison of intravenous digital subtraction angiography and dynamic computed tomography in a follow-up study on 37 patients who had undergone surgery on the thoracic aorta for acute or chronic type A dissections. These are minimally invasive and complementary procedures: IV-DSA provides a clear angiographic image of the dissection, with visualization of the true and false channels, their distal extension and the supra-aortic and abdominal vessels they supply. Dynamic CT best demonstrates the proximal extension of the disease; it visualizes clotting in the false lumen and permits a more accurate measurement of the aortic width, and thus early recognition of a developing aneurysm.

Adult↗
PubMed1988

[The place of radiologic research procedures in the diagnosis of aortic dissection].

Aortic dissection is a rare but life-threatening disease that requires a prompt and exact diagnosis. That is why the radiologist now assumes a central role due to the introduction of new imaging modalities. Each of them can make a contribution while having its own limitations. The choice of the right examination procedure and its correct application determine a successful radiological diagnosis. On the basis of experience with more than 150 operated patients we explain our diagnostic strategy in aortic dissection.

Aortic Dissection↗
PubMed1987

Acute type-A dissection of the aorta: which diagnostic modes remain for surgical indication?

The natural course of acute type-A dissection of the aorta (AADA) implies a mortality of 50% within the initial 2 days. Preoperative diagnostic tests have to be expeditious while avoiding hypertension and direct manipulation of the aneurysm to prevent aortic rupture. Since 1979, 51 patients have been operated upon for AADA. The diagnosis was established by one or more of the following methods: transthoracic echocardiography (TTE); transesophageal echocardiography (TEE); conventional angiography (CA); intravenous digital subtraction angiography (DSA); and computed tomography with bolus injection of contrast medium (CT). TTE (n = 26) showed a dissection in 72%, suggested an intimal flap in 25%, and missed the diagnosis in 1 case. CT (n = 15) and DSA (n = 10) failed to indicate dissection in 1 case each. CA (n = 27) demonstrated dissection in every case but was the most time-consuming and stressful method. Since the introduction of combined transthoracic and transesophageal echocardiography, no other diagnostic methods have been used. On the basis of this experience, we propose the following diagnostic plan: 1. in AADA, the demonstration of an intimal flap in the ascending aorta by TTE/TEE is an indication for immediate surgery without further diagnostic measures (10 patients: no false-positive findings); 2. if a dissection is suggested by TTE/TEE, then DSA is performed if the supra-aortic branches are suspected to be compromised; CT is preferred if an extrapericardial aortic rupture is suspected; 3. the time-consuming and stressful diagnostic approach of conventional angiography is no longer indicated.

Acute Disease↗
PubMed1987

A new look at acute type-A dissection of the aorta.

A new method of treating acute type-A dissection of the aorta is described and illustrated. It involves the reconstruction of both the valve and the ascending aorta. This procedure was employed in 17 patients, 2 of whom succumbed early of complications unrelated to the method while one committed suicide at a later date. One of the surviving patients required reoperation due to breakdown of a resuspended aortic commissure. Two patients show minor non-progressive valve regurgitation in the absence of annulo-aortic ectasia. Two patients have developed dilatation of the aortic root--one will require reoperation in the foreseeable future. In our hands, this method has served to make emergency operation for acute aortic dissection both simpler and safer. The limitations of its use are discussed.

Acute Disease↗
PubMed1987

Surgical decision making in acute aortic dissection type A.

In principle there are 3 different approaches to the treatment of acute aortic dissection type A (AADA): replacement of the aortic valve and ascending aorta, reconstruction of these structures, and a combination of both techniques. This study summarizes our experiences with these methods and delineates indication for the different surgical procedures. Since 1979, a total of 51 patients (39 male, 12 female, mean age 45.5 years) underwent surgery for AADA with an overall mortality of 25%. Differences in mortality of the operative variants (reconstruction 12%, composite replacement 18%, combined reconstruction and replacement 47%) predominantly mirror growing experience than applicability of the methods. The follow-up of patients with reconstruction of the aortic valve revealed a reoperation rate of only 9% after 0.3 to 6.3 years. Four patients with constant and minor annuloectasia and/or subclinical aortic insufficiency are observed in short intervals. We conclude, that the operative procedure in AADA must be adapted to the intraoperative pathoanatomical findings. Patients with primary annuloectasia should undergo graft replacement. Reconstruction of the ascending aorta and aortic valve is considered to be the preferable method in patients with primarily normal caliber of the ascending aorta and aortic anulus.

Adult↗
PubMed1986

[Replacement of the infrarenal aorta in advanced age].

Between 1975 and 1986, infrarenal aortic replacement, due to aneurysm, was performed on 80 patients (mean age 78.4 +/- 3.2 years, 63 men, 17 women). From 28 electively operated patients one died (3.6%), and from 26 urgently operated symptomatic patients, 23.1% (n = 6). Following emergency operations due to rupture, the lethality rate was 50% (13/26). The figures for patients under 75 years of age were: 4.3% (12/277), 10.6% (7/66) and 40.9% (47/125). An analysis of patients, operated in an emergency, on account of ruptured aneurysm or with symptoms, showed that significant cardiovascular and pulmonary risk factors existed. The risk of electively operated patients older than 75 years is not higher than for younger patients. In our opinion, limitation of indication for operation, due to higher age, is not justified.

Aged↗