Biomedical subjects
Publications and source records attributed to O Hoffman.
We have shown that predominance of the jugular veins in cerebrovenous drainage is limited to the supine position. In the erect position, the vertebral venous system represents the major outflow pathway.
A patient was treated by PTA for a tight excentric stenosis in the external iliac artery. Following angioplasty, appropriate placement of a Palmaz stent over the lesion was impossible because of arterial curves and irregular aspect of the residual stenosis. To overcome this problem, the stent was grasped and pulled over the lesion using a snare loop device by contralateral approach.
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Acute femoro-popliteal occlusions (native arteries or bypass grafts) were treated by medical and surgical treatment. Despite improvement in surgical technique, patient mortality was high and limb loss remained frequent. Percutaneous endoluminal treatment of such lesions is feasible using in situ fibrinolysis and/or thromboaspiration singly or in association with balloon angioplasty. Those techniques are effective and are currently the first intention treatment of many of those acute femoro-popliteal occlusion. The advantages and disadvantages of those techniques are discussed, as well as their respective indications, and particularly their place compared to surgical techniques. New devices such as mechanical thrombectomy may increase effectivity and indications of endovascular treatment however such devices need to be better evaluated.
Two cases of isolated calcified lesions of the aorta are reported. The first observation is that of a 25 years old man suffering from mild intermittent claudication predominant in the left leg. Radiological examination showed a calcified isolated lesion of the infra renal abdominal aorta. The patient underwent surgical treatment (thromboendarteriectomy) and was asymptomatic after 6 months. The second observation concerns a 30 years old man treated for benign thrombocytemia in whom a severe arterial hypertension associated with a thoracic bruit was discovered incidentally. Radiological workup demonstrated a solitary calcified lesion of the descending thoracic aorta. Endarteriectomy was performed and the patient was still asymtomatic at 12 months. A review of the literature as well as physiopathological hypothesis and diagnostic and therapeutic management of these uncommon lesions is proposed.
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The aim of this study was to determine the frequency, significance and prognosis of small, abnormal, strand-like echos observed by early transoesophageal echocardiography after mitral mechanical valve replacement with hemi-disc prostheses. One hundred and twenty nine consecutive patients operated between October 1988 and June 1992 underwent transoesophageal echocardiography on average 15 +/- 7 days after surgery. A second transoesophageal echocardiography was performed in 52 patients on average 8 months after the first postoperative examination. The frequency of small strand-like echos and of non-obstructive thromboses of the valve at the initial transoesophageal examination was 43% and 8.5% respectively. A multivariate analysis showed that the only independent predictive factor for prosthetic valve strands was spontaneous intra-atrial contrast (p < 0.01). The presence of strands was significantly related to the prevalence of early thrombo-embolic events (confirmed non-obstructive valve thrombosis and systemic embolism). Strands were observed in 80% of cases with early thromboembolic complications compared with only 38% of cases with no early thromboembolic events (p < 0.04). Univariate analysis showed that the protamine/heparin ratio at the end of cardiopulmonary bypass and the percentage of ineffective postoperative heparinisation were higher in patients with these small, abnormal echos (p < 0.05 and p < 0.001, respectively). These appearances disappear at long-term transoesophageal echocardiographic control examinations in about half the cases. The authors conclude that the majority of these small, abnormal echos are thrombotic in nature and are associated with a higher thromboembolic risk, justifying effective anticoagulation in the first postoperative hours whenever possible, considering the risk of bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)
In a series of 50 patients (22 females, 28 males); 52 ostial renal artery stenoses were treated by transluminal balloon angioplasty. The mean age of patients was 66 years (range 36-81); mean arterial pressures were 181 mmHg for the systolic pressure and 87 mmHg for the diastolic pressure. The mean level of serum creatinine was 179 mumol/l +/- 128. An immediate success was obtained in 86.5% (residual stenosis of 26%). There were 7.6% of immediate failures and 13.5% of residual stenosis above 50%. Mortality within 1 month was observed in 2 patients. Morbidity included one aortic dissection and 5 cholesterol embolisms. After a mean follow-up of 10 months, 78% of the series were controlled: 66.6% exhibited a residual stenosis below 50%, 25.9% had restenosis and 7.4% had an occlusion of the renal artery. Since patients with ostial renal artery stenosis constitute a high surgical risk group, transluminal balloon angioplasty might be considered as an acceptable and safe alternative treatment.
The aim of this study was to evaluate the early postoperative angiographic features of arterial coronary bypass grafts in 83 asymptomatic patients referred consecutively from the surgical unit. The patients aged 33 to 78 years (average 62 years) were operated between August 1989 and March 1992 and received only arterial coronary bypass grafts: 209 arteries bypassed (121 internal mammary including 10 sequential grafts, 46 radial, 36 epigastric including 4 sequential grafts and 6 gastroepiploic arterial grafts), an average of 2.4 bypass grafts per patient. Selective angiography of the arterial grafts was performed systematically between the 7th and 15th postoperative days in patients with uncomplicated recoveries. The native coronary arterial network was opacified only when a graft was "non-functional": haemodynamic (> 70%) stenosis or occlusion. 3.8% of pediculated mammary grafts were occluded. On the other hand, 16.6% of free internal mammary grafts were occluded. None of the radial artery grafts were occluded, but 8% were stenotic. Finally, 30% of epigastric and 50% of the gastroepiploic grafts were occluded. These results confirm the good function of in situ mammary artery grafts by suggest that systematic multiple arterial grafts should be used with caution. Radial artery grafts give very encouraging results which require long-term evaluation. Early postoperative evaluation of coronary arterial grafts provides important information and should be considered a routine procedure.
The authors studied the responses of the main systems of sympathetic and hormonal regulation in valvular aortic stenosis, a special model of dissociation between arterial pressure and left ventricular function. The series comprised 14 patients with an average age of 70 +/- 9 years without diuretic therapy presenting with pure calcific aortic stenosis without other valvular or coronary disease. All were in sinus rhythm; 5 were taking an angiotensin converting enzyme inhibitor. Plasma concentrations of endothelin 1, atrial natriuretic factor (ANF), arginine vasopressin (AVP), catecholamines, plasma renin activity (PRA), angiotensin II and aldosterone were measured in resting, fasting patients, by blood samplings from a peripheral vein immediately before cardiac catheterisation. The results were compared with the severity of the aortic stenosis (aortic valve area greater or less than 0.7 cm2), the ratio of left ventricular work/myocardial mass (greater or less than 0.6) and treatment (with or without ACE inhibitors). Catecholamine levels were much higher in severe aortic stenosis (noradrenaline: 579 +/- 66 pg/ml when valve surface area > 0.7 cm2 versus 900 +/- 92 pg/ml when valve surface area < 0.7 cm2; p < 0.01). Endothelin -1 and AVP concentrations were normal. Whereas PRA was normal, aldosterone levels were increased in patients without treatment by ACE inhibitors. This treatment did not, however, normalise the noradrenaline levels. The increase in ANF concentration was large when left ventricular work decreased with respect to myocardial mass (190.8 +/- 42.3 pg/ml if W/M was decreased versus 82.7 +/- 15.4 pg/ml when W/M was normal): this could be related to the degree of left ventricular hypertrophy.
Blood pressure (BP) variability depends on external and internal factors. Among these, arterial baroreflex play an important role. The matter of this study is to assess the relationship between these two parameters in borderline hypertension (BL). Twenty six BL male hypertensive were recruited for the study, all gave informed consent. Age: 21 +/- 2 years, height: 177 +/- 8 cm, weight: 77 +/- 14 kg. An ambulatory BP monitoring was performed in each one using a Diasys (Novacor) recorder. Measurements were obtained each 15 minutes for 24 hours. Mean, standard deviation and variation coefficient (VC) of BP and heart rate (HR) were computed for 24 hours, daytime (9a.m.-7 p.m.), nighttime (11 p.m.-7 a.m.). Baroreflex sensitivity (BRS) was determined as the ratio of HR variation on systolic BP variation recorded with a Finapres device from the fourth phase of a Valsalva manoeuvre. Mean systolic and diastolic BP values for 24 hours, daytime and nighttime are: 129 +/- 11/73 +/- 13, 137 +/- 14/76 +/- 15, 114 +/- 11/69 +/- 12 mmHg. VC are: 12 +/- 3/15 +/- 3, 9 +/- 3/13 +/- 3, 10 +/- 3/13 +/- 4%. HR values are: 73 +/- 10, 84 +/- 14, 58 +/- 7 b/min, VC are: 24 +/- 5, 17 +/- 4, 17 +/- 7%. Index for BRS = 1.76 +/- 0.65%. There is no correlation between BRS and systolic BP or HR. BRS is correlated to the inverse of systolic daytime BP VC: r = -0.556, p = 0.003. There is no correlation with other parameters. This study provides evidence for a link between BRS and daytime BP variability in borderline hypertension.
PURPOSE: To report the immediate results and the clinical and angiographic outcome of percutaneous angioplasty in patients with ostial renal artery stenosis. MATERIAL AND METHODS: Retrospective review of 52 percutaneous transluminal renal angioplasty (PTRA) procedures for strictly defined ostial atherosclerotic renal artery stenosis in 50 consecutive patients, selected among 670 PTRAs performed between 1983 and 1993. RESULTS: Immediate angiographic success was achieved in 30 arteries (58%) and improvement was achieved in 15 arteries (29%). The procedure was a failure in seven lesions (13%). PTRA was followed by a stent implantation in three lesions (6%). Two patients (4%) died within the first month after PTRA and a major complication occurred in seven other patients (13%). At a mean follow-up of 20.6 months, both systolic and diastolic blood pressure decreased significantly (P = .0006 and P = .0057 respectively). Renal function did not change significantly (P = .73). One patient was lost during follow-up. At angiographic control (mean, 11 months), restenosis occurred in 27% of the cases. There was no recurrence of pulmonary edema at a mean follow-up of 32 months in 50% of the 12 patients who experienced one episode or more before PTRA. CONCLUSIONS: True ostial renal artery stenosis is rare and often reflects severe and multifocal atheromatous disease. In these patients, PTRA might be considered an acceptable and relatively safe treatment that improves blood pressure and stabilizes renal function.