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A Machraoui

Publications and source records attributed to A Machraoui.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Evaluating the measuring accuracy of intravascular ultrasound].

AIM: Intravascular ultrasound investigations are new tomographic imaging methods for evaluation of artery dimensions and wall morphology. The present study was performed to test accuracy and observer variability. METHOD: 3 plastic phantoms and 1 iliacan artery were assessed. The quantitative measurements were made by computerised 3D reconstruction. RESULTS: The plastic phantoms showed ultrasonically three layers of echogenic structures. An intimal fibrous thickening was seen in the iliac artery. The cross sectional diameters were ultrasonically overestimated by 12.6 +/- 5.6%. Due to the lower velocity of sound in water than in blood there were no significant differences to the true diameters. The intra- and interobserved variabilities were determined to 1.4 +/- 0.8% and 2.6 +/- 1.2%. CONCLUSIONS: Intravascular ultrasound provides a reproducible method for measuring vessel lumen diameters with excellent intraobserver and interobserver variabilities. For in vitro examinations the different velocities of sound in different media have to be taken into account.

Humans↗
PubMed1995

[Effect of the degree of revascularization on left ventricular function after aortocoronary bypass operation].

BACKGROUND: The extent of myocardial revascularisation by aortocoronary bypass surgery can only be quantitatively evaluated by using precise criteria. In this retrospective study the effect of coronary surgery on left ventricular function was analyzed. PATIENTS AND METHODS: In 161 patients, 148 male and 13 female, aged 52.5 +/- 7.0 years (33 to 69 years) with 1 (7%), 2 (38%) or 3 vessel disease (55%) the left ventricular function was analyzed by Swan-Ganz catheterization at rest and on exercise, five months before and after coronary bypass operation. Coronary artery and bypass lesions were quantified according to a new detailed score including diseased main or side branches, segment 1 to 3, type of irrigation and area reduction of the artery cross-section. Pulmonary capillary wedge pressure and cardiac index were measured and related to the grade of revascularisation (RG) and pre-operative ejection fraction (EF), classified in the groups RG1 < 50%, n = 54; RG2 50 to 74%, n = 52; RG3 > or = 75%, n = 55, EF1 < 60%, n = 30 and EF2 > or = 60%, n = 129. RESULTS: The change in pulmonary capillary wedge pressure on exercise was in RG1, RG2 and RG3 -26.2%, -29.0% and -40.9%, respectively (p < 0.001). It was significantly higher in RG2 and RG3 than in RG1. The increase in cardiac index on exercise was significant only in groups RG2, RG3 and EF2 (p < 0.005). CONCLUSION: Adequate improvement of left ventricular function can be expected when a grade of revascularisation of 50% and more is achieved.

Adult↗
PubMed1995

Regression of pre-existing coronary artery disease in a donor heart after cardiac transplantation.

This report is about the angiographic follow-up, over 5 years, in a patient with urgent heart transplantation grafted with an atherosclerotic donor heart because of severe congestive heart failure due to dilative cardiomyopathy. Sequential quantitative angiography documented a regression of the luminal narrowing of a focal lesion in the right coronary artery with a minimal luminal diameter of 1.38 mm (56% diameter stenosis) in 1988 to 2.78 mm (13%) in 1993. During this catheterization in 1993 intravascular ultrasound imaging illustrated almost no atherosclerotic vessel wall abnormalities at the site of the previous angiographic luminal narrowing as well as in the adjacent segments. These findings might promote the potential acceptance of heart transplant donors with a certain extent of coronary artery disease in the case of urgent organ request, if close follow-up and strict guidance of the patient by the transplanting team is feasible.

Adolescent↗
PubMed1994

[Diagnostic value of right thoracic ECG recording in detection of pulmonary hypertension in chronic obstructive respiratory disease].

There are many electrocardiographic criteria of pulmonary hypertension and cor pulmonale. These criteria are generally highly specific but not sensitive. Therefore many patients with pulmonary hypertension remain undetected. The aim of this study was to delineate a sensitive as well as a specific ECG parameter for noninvasive prediction of pulmonary hypertension under special consideration of the right thoracic leads. 75 patients were included in this study, 62 male and 13 female, mean age 62.7 +/- 9.5 years. All presented with chronic obstructive lung disease known since 12.1 +/- 9.7 years. The underlying disease had been confirmed clinically and by body plethysmography. Laboratory and lung function data showed a high air way resistance with a mean value of 6.8 +/- 3.3 cm H2O/l/s and a high intrathoracic gas volume of 149.1% of the expected value. The severity of hypoxemia was variable but generally moderate with a PaO2 of 65.3 +/- 11.6 mm Hg on average. All patients applied aerosols with ipratropiumbromid, fenoterol and glucocorticoids. 92% additionally received aminophylline and 87.0% oral glucocorticoids. Diuretics and glycosides were prescribed in 50.0% and 34.8% respectively. The four right thoracic ECG leads Vr3 to Vr6 were recorded in addition to the common twelve leads I to III, a VR, aVL, aVF and V1 to V6. A modified Sokolow-Lyon-Index (SIm) as a sum of amplitudes of R in lead Vr3 and S in lead V6 and the combination of SIm with PaO2 (SIm-PaO2, n = 44) according to the formula SIm + 0.02 (100--PaO2%) were established. Additionally a right heart catherization by Swan-Ganz technique was performed. The mean values of hemodynamic data demonstrated a constellation of precapillary pulmonary hypertension with high PAPm and pulmonary resistance and low pulmonary capillary wedge pressure (26.4 +/- 12.9 mm Hg, 396.0 +/- 294.0 dyn.s./cm5 and 8.7 +/- 4.2 mm Hg, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1993

Two-dimensional echocardiographic assessment of right cardiac pressure overload in patients with chronic obstructive airway disease.

Two-dimensional echocardiography was used to estimate right cardiac pressure overload in patients with chronic obstructive airway disease. Area measurements of the four heart chambers were carried out from the apical four-chamber view. Additionally, the respiratory behaviour of the inferior vena cava was examined from the subcostal view. A good apical imaging of the four-chamber view for area measurement was obtained in 44 out of 48 patients with chronic obstructive airway disease. The respiratory behaviour of the inferior vena cava was investigated from the subcostal view in 38 patients. Within 8 days after echocardiography, right cardiac catheterization was carried out in order to measure pulmonary artery and right atrial mean pressures and to determine pulmonary vascular resistance. A good correlation was found between pulmonary artery mean pressure and the following echocardiographic parameters: area index (area/body surface) of the two right heart cavities (r = 0.83), right-to-left ventricular area ratio (r = 0.82) and right-to-left cardiac area ratio (ratio between the added areas of both right heart cavities on the one side and the added areas of both left heart cavities on the other; r = 0.82). Correlation between these parameters and pulmonary vascular resistance (r = 0.71, 0.66 and 0.71, respectively) and between the right atrial mean pressure and the right atrial area index was less close (r = 0.64). On the other hand, the respiratory behaviour of the inferior vena cava proved to be highly specific but not very sensitive in predicting a pathological right atrial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Atrial Function, Right↗
PubMed1992

[The importance of 201-thallium myocardial scintigraphy in the hypertensive patient].

Thallium-201 exercise myocardial scintigraphy was performed in 57 patients (37 males, 20 females; mean age 55.4 [43-78] years) with angina and systemic hypertension after exclusion by coronary angiography of any coronary macroangiopathy. The exercise ECG of 32 patients could not be used in the diagnosis of ischaemia because of the presence of left ventricular hypertrophy with abnormal repolarization or left bundle branch block. Abnormal haemodynamics were demonstrated at cardiac catheterization in 23 patients (Swan-Ganz). Only 10 of the studied hypertensives with normal coronary angiograms had a myocardial scintigram within normal limits, while 12 had extensive ischaemic zones in the left ventricle. All patients with left bundle branch block had evidence of exercise-dependent apical "ischaemia". Thallium-201 myocardial scintigraphy should not be used as a screening method in hypertensives with angina, because the high proportion of "false-positive" findings, in the sense of a macroangiopathy, will nevertheless require early invasive diagnosis.

Adult↗
PubMed1992

Efficacy and safety of APSAC in the treatment of acute myocardial infarction.

A prospective, open, multicentre post-marketing surveillance on the efficacy and safety of intravenous APSAC in the treatment of acute myocardial infarction was performed in 2436 patients. Reperfusion suggested by non-invasive parameters was achieved in 77.3% of patients. In-hospital mortality was low (7.1%). After exclusion from analysis of patients greater than 70 years of age and those reported to be in cardiogenic shock, mortality rate was 2.9%. More importantly, non-invasive evidence for successful thrombolysis resulted in a significantly lower mortality (3.3%) compared with patients without evidence of successful reperfusion (17.2%). The incidence of serious adverse events was low (132 in 2436 patients, 8/2436 = 0.3% fatal). The data from this post-marketing surveillance conducted under every-day clinical conditions confirm the efficacy and safety of APSAC as a thrombolytic agent in acute myocardial infarction, as demonstrated previously in controlled clinical trials.

Acute Disease↗
PubMed1992

Aerobic capacity in rate modulated pacing.

Whether heart rate or AV synchrony is the most important factor for an increase in aerobic capacity was evaluated in a comparative study between sinus bradycardia, VVIR, DDD, and DDDR stimulation. Sixteen patients (mean age 67 years) with chronotropic incompetence and implanted DDDR pacemaker (Telectronics META 1250) were randomly studied by cardiopulmonary exercise testing. All patients were exercised to their anaerobic threshold (AT) with the following heart rates: DDD 84 +/- 3, VVIR 110 +/- 5, and DDDR 116 +/- 6 beats/min. Mean oxygen uptake (VO2, mL/kg per min) at AT was 7.4 +/- 0.3 in DDD and VVIR modes. A 12% increase was measured in DDDR mode (8.3 +/- 0.4). Compared to VVIR work capacity in the DDDR mode was improved by 17% (41 vs 48 W/min). In patients with isolated sinus node disease (n = 9) the increase of VO2 and work capacity at AT during DDDR mode was more pronounced (16% and 20%, respectively, compared to VVIR). In patients with intermittent second or third degree AV block (n = 7) the differences between the pacing modes were not significant. This might partly be due to a lesser degree of chronotropic incompetence in this subgroup. In conclusion only the conjunction of heart rate increase and preservation of AV synchrony provides a significant improvement in aerobic capacity during exercise.

Aged↗
PubMed1991

[Intolerance reactions to ionic and nonionic contrast media in cardiac diagnosis. A randomized double-blind study].

Reactions to an ionic and a nonionic contrast medium were compared in a randomized double-blind trial involving 1153 patients (897 men, 256 women; mean age 56 [18-84] years) who underwent left-heart catheterization with coronary angiography. 584 patients (group 1) received the ionic contrast medium meglumine diatrizoate (Urografin 76%), while 569 (group 2) received the nonionic iopromide (Ultravist -370). Reactions of skin and mucosae, heart and circulation, lungs and respiratory tract, as well as of the central nervous system were noted. There was no significant difference between the two groups with respect to age, weight, height, allergic predisposition, left-ventricular ejection fraction, or serum electrolyte concentrations. Mild reactions, not requiring any treatment, occurred in 108 of the 1153 patients (9.4%), 85 (14.6%) in group 1 and 23 (4%) in group 2 (P less than 0.001). Severe reaction requiring treatment occurred in eight patients of group 1 (1.4%) and 14 of group 2 (2.5%)--difference not significant. Ventricular fibrillation was more frequent among group 2 patients (four compared with one in group 1), while two of three asystoles requiring treatment occurred in group 1 patients. The results show that, while mild reactions not requiring treatment were clearly less frequent after nonionic contrast medium injection, the risk of severe reactions was not reduced by their use.

Adolescent↗
PubMed1990

[Systemic fibrinolysis following resuscitation or temporary electrostimulation].

Short-term systemic thrombolytic treatment with 1.5 million I.U. streptokinase or 1.8 million I.U. urokinase or APSAC was carried out in 13 patients with acute myocardial infarction (11 men, 2 women, mean age 61 [44-73] years) after cardiopulmonary resuscitation (n = 11) or transvenous electrostimulation (n = 2). In seven of the patients the infarct vessel was found to be patent after the course of thrombolytic therapy. No haemorrhagic complications occurred. Two patients died: one of a reinfarct at 3 months and the other suddenly at home at 6 months. These results show that short-term high dosage systemic thrombolytic treatment can be successfully performed in individual cases even after resuscitation or central venous catheterization, provided that any serious traumatic lesions or inadvertent arterial punctures have been avoided.

Aged↗
PubMed1990

[Prognosis in cor pulmonale: predictive value of two-dimensional echocardiography].

Cor pulmonale is a common complication and frequent cause of death in COLD. No published records are as yet available on the prognostic ranking of two-dimensional echo-cardiography in this group of patients. In 79 of 85 (93%) consecutively echocardiographically examined COLD patients it was possible to effect apical imaging of the four-chamber view to assess the size of the right ventricle, as well as a subcostal imaging to analyse the respiratory performance of the vena cava inferior (vci). Among the exclusion criteria of this prospective series were a diseased condition of the left heart or other associated cardiac diseases. The patients were classified into two risk groups (RG 0 and RG 1) depending upon whether they had a normal-sized right ventricle or a complete inspiratory collapse of the vci, or not. In RG 1 the pO2 values were lower (56.8 +/- 9.2 vs 66.0 +/- 8.8 mmHg, p less than 0.0005) whereas the values for the respiratory passage resistance were higher (8.01 +/- 3.92 vs 6.22 +/- 2.87 cm H2O/l/s; p less than 0.025) than with RG 0, the values for the intrathoracic gas volume not being significantly different from each other. Fatal cardiopulmonary results were covered over a period of 2-48 months (median 24 months) to perform life table analyses according to Breslow and Mantel. Patients with an enlarged right ventricle or incomplete respiratory collapse of the vci have a lower survival rate (43.7% respectively 61.9%) than patients with a normal-size right ventricle or complete respiratory collapse of the vci (90.5% respectively 88%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Pulmonary gas exchange in conventional ventilation and high frequency ventilation in severe respiratory insufficiency].

During high frequency jet ventilation (HFJV) adequate alveolar ventilation may be achieved with lower (-35%, p less than 0.0005) central airway pressures than during conventional mechanical ventilation (CMV). Due to increasing ventilation-perfusion inequalities, however, intrapulmonary shunt is then considerably increased (+52%, p less than 0.0005). In disease states with extensive shunting (e.g. ARDS) both ventilation modes can provide sufficient oxygenation only if high PEEP is applied.

High-Frequency Jet Ventilation↗