Biomedical subjects

C Cracowski

Publications and source records attributed to C Cracowski.

6 recordsLinked to original sources

PubMed2004

[Biomarkers as prognostic factors in pulmonary arterial hypertension. Rationale and study design].

CURRENT SITUATION: Pulmonary arterial hypertension (PAH) is a serious disease. Its prognostic is based on the functional status quantified by the NYHA class and the 6-min walking test, and the hemodynamic data. The algorithms of treatment are solely based on the hemodynamic data and the functional status. The main objective is to test whether basal concentrations of isoprostanes, Big endotheline 1, ADMA, high sensitivity CRP, NT-Pro-BNP and cardiac troponin T are a 3-year prognostic factor in PAH using a combined criterion: death from any cause and pulmonary or cardiopulmonary transplantation. MATERIALS AND METHODS: This is a multicenter, prospective, prognostic, single blinded study (plasma and urinary samples being blinded). The study started in november 2003, running for 2 years, with a 3 year follow-up for each patient. The main inclusion criterion is PAH. The data analysis will use a multivariable Cox model, taking into account the functional and hemodynamic parameters. EXPECTED RESULTS: This study will determine whether any of the biomarkers tested provides additional prognostic information in PAH in addition to the functional and hemodynamic parameters.

Biomarkers↗

PubMed2001

Characterization of obstructive nonapneic respiratory events in moderate sleep apnea syndrome.

Obstructive nonapneic respiratory events (ONAREs, i.e., obstructive hypopneas [OHs] and respiratory effort related arousals [RERAs]) are clinically important as producing sleep fragmentation but are much more difficult to detect and classify than obstructive apneas. We characterized 1,061 ONAREs in 15 unselected patients with moderate sleep apnea-hypopnea syndrome (OSAHS) according to the 1999 American Academy of Sleep Medicine (AASM) Task Force recommendations concerning accurate skills for respiratory measurements (i.e., pneumotachograph and esophageal pressure [Pes]) and definitions of respiratory events. OHs were defined as > or = 50% decrease in flow or < 50% but > or = 30% decrease in flow associated with either a desaturation of > or = 3% or a cortical arousal. RERAs corresponded to a less than 30% decrease in flow associated with an arousal. OHs represented a large majority of the events (79.9%, n = 848). Among the events demonstrating a 30 to 50% reduction in flow (n = 392), the occurrence of a cortical arousal permitted the classification of 246 events as OHs (62.8%). RERAs represented only 5.3% of the events. Finally 14.8% of the events were classified as indeterminate owing to a < 50% and > or = 30% airflow decrease without arousal or desaturation or an airflow decrease less than 30% without arousal. The same level of DeltaPes was observed at the end of OHs and RERAs (21.9 +/- 5.5 versus 18.9 +/- 5.7 cm H(2)O respectively [NS]) whereas the reduction in flow was as expected, higher for OH (57.9 +/- 10.7 versus 21.3 +/- 4.9%). In a population of moderate OSAHS, OH represented the dominant type of ONAREs when RERAs should be considered as specific but relatively rare respiratory events. The occurrence and the recognition of a microarousal represented the key associated factor for classifying respiratory events as hypopneas. The high rate (15%) of unclassified events demonstrated some limitations in the AASM Task Force recommendations for definitions of respiratory events. Similar levels of DeltaPes found at the end of RERAs and OHs, although the reduction in flow was higher for OHs, suggest that different levels of collapsibility can exist throughout the night in a given patient.

Data Interpretation, Statistical↗

PubMed2001

Increased lipid peroxidation in patients with pulmonary hypertension.

Isoprostanes are chemically stable lipid peroxidation products of arachidonic acid, the quantification of which provides a novel approach to the assessment of oxidative stress in vivo. The main objective of this study was to quantify the urinary levels of isoprostaglandin F(2alpha) type III (iPF(2alpha)-III), an F(2)-isoprostane, in patients with pulmonary hypertension (PHT) in comparison with healthy controls. The secondary objective was to test whether baseline iPF(2alpha)-III levels correlate to the reversibility of pulmonary hypertension in response to inhaled NO challenge. Urinary iPF(2alpha)-III levels were measured by gas chromatography-mass spectrometry in 25 patients with PHT, 14 of whom were investigated for response to inhaled NO challenge. Urinary iPF(2alpha)-III levels in PHT patients (225 +/- 27 pmol/mmol creatinine) were 2.3 times as high as in controls (97 +/- 7 pmol/mmol creatinine, p < 0.001). The mean pulmonary arterial pressure variation and the pulmonary vascular resistance variation in response to inhaled NO were correlated to basal iPF(2alpha)-III levels. This study shows that oxidative stress is increased in patients with pulmonary hypertension. Furthermore, iPF(2alpha)-III levels inversely correlate to pulmonary vasoreactivity. These observations are consistent with the hypothesis that free radical generation is involved in PHT pathogenesis.

Adolescent↗

PubMed1998

Lung function and exercise capacity in thalassaemia major.

Lung function abnormalities in thalassaemia major are various and complex; however, patients still die from cardiac lesions. This study aimed to investigate pulmonary and cardiac involvement at an early stage in thalassaemic patients and study their respective implications at rest and during exercise. Ten patients (five adults and five children) with thalassaemia major were investigated by echocardiography, lung function and exercise testing a few days after transfusion. All have had regular transfusions and chelation with deferoxamine and none had chronic pulmonary disease symptoms. Minor lung function abnormalities were found: two patients had moderate obstructive syndrome and two had a decreased carbon monoxide transfer factor. Hypoxaemia was never found at rest and no desaturation was observed at the end of exercise. Echocardiographic abnormalities were also moderate. Peak oxygen consumption (V'O2) was decreased in three adults and was lower in adults than children (means 27.7+/-4.6 and 41.1+/-4.8 mL.kg(-1).min(-2) respectively). The V'O2/cardiac frequency slope was lower in adults than children (0.25+/-0.06 versus 0.42+/-0.10 mL.kg(-1).min(-2)), whereas end-exercise breathing reserve was >40% maximal voluntary ventilation for all patients. In conclusion, none of the patients had ventilatory limitations but older patients had cardiac limitations assessed by the relationship between oxygen consumption and cardiac frequency. Exercise testing may detect cardiac impairment in thalassaemia major earlier than investigations at rest.

Adolescent↗

PubMed1998

[Deep venous thrombosis and severe burns].

Deep venous thrombosis (DVT) is a frequent and potentially serious complication in severely burned patients. We report the case of a burned patient (40% of total body surface burned), who had right femoral deep venous thrombosis and severe pulmonary embolism, although a prophylaxis was conducted with low molecular weight heparin, graduated compression stockings and rotating bed. This case shows that DVT early diagnosis and prophylaxis is difficult in severely burned patients. Systematic screening of DVT by duplex scan is possible only for femoral veins, which renders duplex scan more suitable for femoral catheter follow up than for systematic DVT screening. Computed tomography venography seems to be a valuable tool in the diagnosis of proximal thrombosis. Prophylaxis is best achieved with the use of preventive low molecular weight heparins, graduated compression stockings, and early mobilisation when possible. However, the place of low molecular weight heparins at high doses and external pneumatic calf compression needs to be evaluated by prospective studies.

Adult↗

PubMed1997

[Non-invasive management of a serious acute pulmonary embolism].

Prompt diagnosis of a large pulmonary embolus is essential in order to initiate appropriate treatment early. We report a case of a large pulmonary embolus in which management was aided solely by noninvasive investigations. Transthoracic echocardiogram showed elevated right heart pressures which together with the patient symptoms suggested a major pulmonary embolus. Spiral computed tomography of the chest confirmed the diagnosis. The source of the embolus was shown by echodoppler. This case illustrates that a diagnosis of a major pulmonary embolus can be made using noninvasive techniques. Pulmonary angiography should be reserved for those rare cases in which diagnostic uncertainty remains rather than being used as a routine examination prior to consideration of therapeutic decision.

Acute Disease↗