Biomedical subjects

C Sabba

Publications and source records attributed to C Sabba.

8 recordsLinked to original sources

PubMed1997

Effect of propionyl-L-carnitine on quality of life in intermittent claudication.

A double-blind, dose titration study was designed to assess the efficacy of propionyl-L-carnitine in intermittent claudication. The effect on walking capacity was described in a previous article. This study reports on the effect on quality of life, assessed by the McMaster Health Index Questionnaire (MHIQ). After 24 weeks of treatment, the global MHIQ score did not show any difference from baseline in patients randomized to placebo (n = 102). Conversely, it increased from 0.59 +/- 0.12 to 0.64 +/- 0.12 in those taking propionyl-L-carnitine (n = 85). Analysis of variance showed a significant difference between treatments (p = 0.018). Stepwise multiple regression analysis identified baseline maximal walking capacity (cutoff point 250 m) as a predictor of treatment outcome. In patients walking < 250 m, propionyl-L-carnitine significantly improved physical function (p = 0.027), emotional function (p = 0.002), and global MHIQ score (p = 0.002) compared with placebo. Also, for maximal walking capacity, group difference significantly favored propionyl-L-carnitine (p = 0.009). In patients with baseline maximal walking capacity > or = 250 m, propionyl-L-carnitine did not affect the MHIQ scores, nor improve walking performance. These data indicate that propionyl-L-carnitine exerts beneficial effects on quality of life and walking performance in patients with more severely limited walking capacity.

Aged↗

PubMed1996

Quality of life in patients with intermittent claudication: relationship with laboratory exercise performance.

In patients with peripheral arterial disease, limitation of exercise capacity will reduce the level of everyday physical activity and affect the quality of life. This study was designed (1) to examine the health-related quality of life of patients with intermittent claudication, and (2) to verify whether treadmill performance is related to the patient's perceived ability to function in the community. In 251 patients with intermittent claudication and 89 matched normal subjects, quality of life was assessed by a general health index questionnaire, the McMaster Health Index Questionnaire (MHIQ), which covers three dimensions of life (physical, social and emotional function). The maximal walking capacity of intermittent claudication patients was measured by the treadmill test. When controls were compared to intermittent claudication patients using the MHIQ, it was found that intermittent claudication patients showed a significant (p < 0.01) impairment of 'general health' and lower scores for physical (0.90 +/- 0.17 vs 0.65 +/- 0.17; p < 0.01), social (0.71 +/- 0.11 vs 0.63 +/- 0.12; p < 0.01) and emotional (0.75 +/- 0.17 vs 0.65 +/- 0.15; p < 0.01) function. Age, gender and work status had a significant impact upon health scores in several areas. Treadmill performance did not correlate with social or emotional function, whereas there was a small but significant relationship between maximal walking capacity and physical function scores (r = 0.197; p < 0.01). This study suggests that impairment in quality of life experience by patients with intermittent claudication poorly correlates with the reduced exercised capacity assessed by the treadmill test. Therefore, the evaluation of medical and surgical treatment of intermittent claudication should include the administration of a questionnaire for quality of life assessment.

Aged↗

PubMed1993

[Echo-color Doppler in the study of portal hypertension].

Color-Doppler US is currently an extremely valuable tool in the study of abdominal circulation, cirrhosis of liver and its complications, different kinds of portal hypertension, vascular/avascular liver malformations and, finally, in the evaluation of liver transplants. Moreover, its use in experimental studies has yielded good results. Even spontaneous porto-systemic shunts can be demonstrated in most cases (up to 88%). Color-Doppler allows partial obstructions to be demonstrated and permits qualitative and quantitative dynamic evaluations the presence/absence of flow, vascular masses--e.g., mean velocity measurement and blood flow assessment. The interobserver variability of the method was calculated with a double-blind study carried out by our laboratory team cooperating with a study group from the University of Yale, USA. The study evidenced how color-Doppler US cannot be used to follow the single patient unless the variations to measure are higher than variability itself. Color-Doppler limitations depend on the subjectivity of the results and on its difficult application to obese patients or to those with severe intestinal meteorism.

Color↗

PubMed1992

Impaired endothelium-mediated vasodilation in the peripheral vasculature of patients with congestive heart failure.

Impaired endothelial-dependent vasodilation has been demonstrated in two animal models of congestive heart failure and in the coronary circulation of patients with idiopathic dilated cardiomyopathy. To determine whether this impairment contributes to the abnormal peripheral vasomotor tone in patients with congestive heart failure, the local vascular response to intraarterial infusions of graded concentrations (10(-8) M to 10(-5) M) of acetylcholine (an endothelial-dependent vasodilator) and nitroglycerin (a direct-acting vasodilator) was studied in the superficial femoral artery of 19 patients with congestive heart failure (New York Heart Association classes I to IV) and 6 age-matched normal control subjects. The local vascular response was determined from the arterial blood flow velocity pattern obtained by transcutaneous Doppler ultrasonography. Acetylcholine, 10(-5) M, induced a pattern characteristic of vasodilation in all six normal subjects; mean blood flow velocity for the group significantly increased from 11.9 +/- 2.7 to 44.8 +/- 20.9 cm/s (p less than 0.05). In contrast, the same dose of acetylcholine induced a blood flow velocity pattern characteristic of vasodilation in only 4 of the 19 patients with congestive heart failure. Group mean blood flow velocity did not change significantly. Nitroglycerin, 10(-7) M, induced vasodilation in all 6 normal subjects but in only 1 of 19 patients. Nitroglycerin, 10(-5) M, was administered to 10 patients; all 10 demonstrated a pattern characteristic of vasodilation. Thus, acetylcholine-mediated endothelial-dependent vasodilation appears to be impaired in the peripheral vasculature of patients with congestive heart failure. Both endothelial dysfunction and abnormal vascular smooth muscle responsiveness may contribute to abnormal peripheral vasomotor tone.

Acetylcholine↗

PubMed1990

Splanchnic and systemic hemodynamics in mice using a radioactive microsphere technique.

Mice are commonly used for the study of human disease processes. However, techniques for measuring systemic and hepatic blood flow in mice have not been developed. We attempted the conventional technique of radiolabeled microsphere injection into the left ventricle, but difficulties were encountered, including unsuspected ventricular perforation and outflow obstruction in 68% of the animals. We therefore evaluated whether an injection into the carotid artery close to the aortic arch can fulfill the criteria (approximately or greater than 300 microspheres in femoral blood or tissues, adequate mixing of microspheres with blood, and no significant alteration of blood pressure during microsphere injection) required for accurate measurement of systemic and regional hemodynamics. Carotid artery injection resulted in adequate mixing and number of microspheres in tissues in 78 and 91% of the animals, respectively. Portal venous inflow was 1.8 +/- 0.3 ml.min-1.g liver tissue-1 and renal blood flow was 5.1 +/- 0.75 ml.min-1.g tissue-1. Compared per unit weight, these values are quite similar to those reported in rats. Cardiac output was 12.1 +/- 1.2 ml/min and cardiac index was 462 +/- 47 ml.min-1.kg body wt-1. The reliability of cardiac output determination is improved if whole body radioactivity is taken into account. Five of 22 animals had to be excluded because of either a low number of microspheres in tissues or inadequate mixing of microspheres with blood (shown by asymmetrical distribution of microspheres between left and right kidney). With modifications, the radioactive microsphere technique can be adapted to the hemodynamic study of mice.

Animals↗

PubMed1987

Portal hemodynamics after meal in normal subjects and in patients with chronic liver disease studied by echo-Doppler flowmeter.

Changes of portal, superior mesenteric, and splenic venous flows after a meal were studied with the duplex ultrasonic Doppler flowmeter in normal subjects, in patients with chronic active hepatitis, and in those with cirrhosis for 2 h after ingestion of a liquid meal (14% protein, 56% lipid, 30% carbohydrate, 300 kcal). Portal and superior mesenteric venous flows increased significantly throughout the experiment, whereas no significant change occurred in splenic venous flow after the meal in all three groups. The extent of the increase in portal venous flow was significantly lower in patients with cirrhosis, compared with normal subjects and patients with chronic active hepatitis, whereas superior mesenteric venous flow increased to the same extent in all three groups. The sum of superior mesenteric and splenic venous flows was less than the estimated portal venous flow in both normal subjects and patients with chronic active hepatitis; however, this value was greater than the portal venous flow in patients with cirrhosis. The difference widened during postprandial mesenteric hyperemia, indicating an increase of blood flow into the portal-systemic shunts. In conclusion 1) postprandial hyperemia occurs in the intestine, but not in the spleen, to the same extent in patients with chronic active hepatitis or with cirrhosis, as in normal subjects, and 2) a considerable amount of postprandial mesenteric hyperemia bypasses the liver into the systemic circulation of patients with cirrhosis but not in patients with chronic active hepatitis and normal subjects.

Adult↗

PubMed1981

[Spectral analysis of frequencies by conventional Doppler effect examination of the supra-aortic trunks (author's transl)].

Using a directional Doppler (4 MHz) coupled to a frequency analyser, authors investigate the supra-aortic trunks on 90 patients documented by arteriography. The analyser is made of a 16 filter bank system giving a spectrum composed of 16 frequency bands within range of 160 Hz to 4,800 Hz. Data analysis is made on a computer using the comparison means test and the discriminant analysis. Authors compare frequencies on normal common carotid arteries between a group (N = 102) with internal and external carotid arteries free of lesions on one hand, and a group (N = 75) with stenosis or occlusion of internal and/or external carotid arteries on the other hand. They don't note any significant difference for each on of the 16 frequency bands. Comparison of frequencies between normal subclavian arteries (N = 115) and subclavian arteries with proximal stenosis or occlusion (N = 24) shows a significant difference concerning the following bands : F12, F14, F15, F16 (p = 0.05), F13 (p = 0.01). Comparison of frequencies between normal internal carotid arteries (N = 108) and stenosed internal carotid arteries (N = 57) shows significant difference concerning : F11 (p = 0.05), F7, F8, F9, F12, F13, F14, F15, F16 (p = 0.01). On the other side, the discriminant function distinguishes a normal internal carotid artery from a stenosed internal carotid artery in 90% of cases, whatever the stenosis degree is. A discriminant function, added to this analyser, could obtain a frequency analysis easier and less expensive than by fast Fourier transform.

Arterial Occlusive Diseases↗

PubMed1980

[Pre-occlusive stenosis of the internal carotid artery. Haemodynamic study by Doppler effect, phonoangiography-oculoplethysmography and arteriography (author's transl)].

The diagnosis of near total occlusion of the internal carotid artery was made on a group of 122 patients (90 symptomatic - 32 asymptomatic) by Doppler examination on one hand and carotid phonoangiography and oculoplethysmography, used together, on the other hand. The angiographic examination, including the study of the extra cranial arteries and the intra cerebral vessels, was performed. It has shown that a stenosis (greater than or equal to 90% of an internal carotid artery was the only lesion on 65 patients (53.3%) and that in 57 cases (46.7%) there were multiple lesions. 96 patients (76 symptomatic - 20 asymptomatic) were operated on. 4 patients (4.2%) died but the mortality was none in the group of 20 asymptomatic patients. 19 patients refused the operation and we have noted 7 occlusions of the internal carotid artery and 2 patients died (10.2%). On 7 patients with a surgical contra indication we have noted 1 secondary occlusion. We have to consider a near total occlusion of the internal carotid artery as an emergency. Its diagnosis by non invasive techniques must be followed by heparin therapy and angiographic examination. The carotid endarterectomy will respect the external carotid artery patency.

Angiography↗