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G Habib

Publications and source records attributed to G Habib.

At least 91 records · Page 5Linked to original sources
PubMed1996

[Magnetic resonance angiography. Value for evaluating the patency of aortocoronary bypass].

OBJECTIVE: Assessment of coronary bypass patency with conventional angiography can be limited by difficulties in selective catheterism. The aim of this work was to determine whether ultrarapid sequences proposed for imaging coronary arteries could be used to evaluate bypass patency. METHODS: Twenty patients (mean age 66 +/- 7 years) with 42 aorto-coronary bypasses (32 venous and 10 mammary bypasses) underwent conventional angiography and magnetic resonance angiography within a 1 week interval. All patients were evaluated 1 to 15 years after bypass surgery. Magnetic resonance imaging (MRI) was performed in ventral supine position using a flexible surface coil. Breathhold electrocardiogram-synchronized sequences were acquired using a 1.5 T magnet, with TR = 156 ms, TE = 8 ms, slice thickness 5 mm, 126.256 matrix, and a 7 to 11 segmentation per cardiac cycle. At most, 24 transverse slices were acquired for each patient. RESULTS: Twenty-six patent bypasses were correctly identified with MRI. Three bypass were patent on angiography and appeared occluded on MRI (2 mammary and 1 venous bypass). Nine bypasses were classed as occluded with both techniques. MRI demonstrated patency in one bypass for which selective catheterism was not possible. The sensitivity of MRI for the diagnosis of patency in aorto-coronary bypasses was 89% with a 92% specificity. MRI did not identify 1 out of 4 bypass stenoses. CONCLUSION: We conclude that the ultrarapid breath-hold magnetic resonance sequences can be used to determine patency of aorto-coronary bypasses with good sensitivity and specificity. Our results would suggest however that this method is inadequate for the diagnosis of bypass stenosis.

Aged↗
PubMed1996

Modification of the diagnostic criteria proposed by the Duke Endocarditis Service to permit improved diagnosis of Q fever endocarditis.

BACKGROUND: Q fever endocarditis is a life-threatening disease for which the diagnosis is usually based on serology. The major microbiologic criterion for the diagnosis of infectious endocarditis (two separate positive blood cultures) cannot be achieved in most routine laboratories because of the biohazard associated with the culture of Coxiella burnetii, the etiological agent of Q fever. PURPOSE: Recently, new criteria for the diagnosis of infectious endocarditis have been proposed, and in this study we attempted to assess the suitability of these criteria specifically for the diagnosis of Q fever endocarditis. PATIENTS AND METHODS: To achieve this aim, we first selected from our series 20 recent cases in whom endocarditis had been confirmed following valvular pathological examination, and for whom microbiological evidence for the involvement of C burnetii was available. Then, we applied the criteria proposed by the Duke Endocarditis Service (ie, C burnetii positive serology being considered a minor criterion) to this cohort of patients but excluding pathological findings. Although the Duke Endocarditis Service criteria confirmed diagnosis in 16 of the patients, 4 were misclassified as "possible" cases (20%). However, when the Q fever serological results (using an 1/800 antiphase I immunoglobulin G cut off) and single blood culture results were changed from minor to major diagnostic criteria, endocarditis was confirmed in them all. A second time, prospectively, we applied the Duke Endocarditis Service criteria to a further 5 patients affected with Q fever endocarditis. Strict application of these criteria resulted in 1 of the 5 being misdiagnosed. Applying the suggested modification for C burnetii results, all 5 were confirmed as having infectious endocarditis. CONCLUSION: We propose that the modifications discussed in this study be applied to the Duke Endocarditis Service criteria in order that the diagnosis of C burnetii induced endocarditis is improved.

Coxiella burnetii↗
PubMed1996

False aneurysm: a rare and potentially severe complication after pulmonary autograft operation.

A case of a false aneurysm arising at the proximal suture of an aortic root replacement with a pulmonary autograft is presented. This complication did not occur in the first postoperative month but was discovered late, and the female eight-year-old patient was in an extremely serious condition. She was reoperated on an emergency basis but died of acute pulmonary artery hypertension. The mechanism of the occurrence of such a case is discussed. In the absence of infection, structural weakness of the right ventricular muscle with progressive tearing is suggested. Strict and prolonged echocardiographic surveillance after the Ross procedure and early reoperation are mandatory.

Aneurysm, False↗
PubMed1996

[Value of echocardiography in the study of aortic valve homografts and autografts].

Although increasingly used, the echocardiographic parameters of aortic valve homografts and autografts have not been extensively investigated. The aim of this study was to assess the value of transthoracic (TTE) and transoesophageal (TOE) echocardiography in the preoperative assessment of these patients, especially with regards to prediction of homograft size and to describe the normal and pathological echocardiographic appearances of this type of prosthesis. Thirty-seven consecutive patients were studied. Before surgery, the diameter of the aortic ring (24.1 +/- 3 mm), correlated well with the value measured by the surgeon (24.4 +/- 2 mm; r = 0.9), but in 2 cases, this measurement was impossible and in 3 cases inaccurate, the difference between the 2 measurements being greater than 2 mm. It was possible to measure the aortic ring diameter in all cases by TOE. After surgery, TTE showed normal function of 33 of the 37 prosthetic valves with minimal or no obstruction (mean gradient 5.9 +/- 4 mmHg, aortic surface area = 2.8 +/- 0.5 cm2) with no significant difference between the homografts and autografts. Better visualisation of the homograft leaflets was possible by TOE and detected minimal central regurgition in 16 (84%) of the homografts examined, the persistence of an annular abscess in 2 patients and a minimal aorto-left atrial fistula in 1 patient. In conclusion. TTE coupled with Doppler examination is usually adequate for preoperative selection of the homografts and haemodynamic evaluation and follow-up of these patients. TOE should be performed preoperatively in patients with unsatisfactory TTE studies but is mainly useful for preoperative evaluation and postoperative follow-up of patients operated for aortic endocarditis with paravalvula abscess.

Adolescent↗
PubMed1996

[Lymphoma in the transplanted heart].

Lymphoma is a classical complication of cardiac transplantation. The authors report a case in which the disease affected the cardiac graft. There were few symptoms and a good response to treatment was obtained. The patient underwent cardiac transplantation at 48 years of age because of primary dilated cardiomyopathy. Four years later, she presented with general ill health and a left supraclavicular lymphadenopathy which led to the diagnosis of a tumour of the atria extending into the mediastinum. MRI was the investigation which gave the best images of tumour extension. As with most late lymphomas of transplanted patients, the proliferation was a monoclonal B type. A significant reduction of tumour size was observed during the 13 months follow-up with chemotherapy and there were no cardiac functional signs.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

[Abnormal origin of the left coronary artery from the pulmonary artery. Diagnostic contribution of ultrasonographic technique].

We report a case of abnormal origin of the left coronary artery from the pulmonary artery trunk. The original features of this case were its discovery in a young pregnant woman, the normality of basal left ventricular function and the electrocardiogram, the diagnosis by transoesophaegeal echocardiography, and the demonstration of severe myocardial ischaemia by stress echocardiography.

Adult↗
PubMed1995

Standard orthotopic heart transplantation versus total orthotopic heart transplantation. A transesophageal echocardiography study of the incidence of left atrial thrombosis.

BACKGROUND: After standard orthotopic heart transplantation (Sd HT), the enlarged resultant atria may promote atrial thrombosis. The purpose of this study was to compare the incidence of spontaneous echo contrast and left atrial thrombosis after Sd HT and total orthotopic (Tot HT) heart transplantation. METHODS AND RESULTS: Transesophageal echocardiography (TEE) was performed in 75 patients with Sd HT and in 20 patients with Tot HT. Despite the use of antiplatelet therapy, an acute arterial embolism occurred in 11 (15%) of the 75 patients with Sd HT but in none of the 20 Tot HT patients. All patients were in sinus rhythm. Left ventricular ejection fraction was similar in Sd HT and Tot HT patients. Left atrial diameter was smaller in Tot HT patients than in Sd HT patients (41 +/- 4 versus 58 +/- 6 mm, P < .001). In Sd HT patients, spontaneous echo contrast was present in 43 patients (57%) and was associated with left atrial thrombus in 20 patients (on the left atrial appendage in 12 patients, on the posterior wall in 6, and on the suture in 2). No thrombus was detected by transthoracic echocardiography; all thrombi were detected by TEE. On the other hand, no left atrial thrombus was observed in Tot HT patients, and only 1 patient had spontaneous echo contrast. Of the 11 Sd HT patients who experienced an arterial embolism, 5 had both spontaneous echo contrast and left atrial thrombus and 5 had only spontaneous echo contrast. CONCLUSIONS: This study demonstrates a high rate of left atrial thrombus after Sd HT and emphasizes the role of TEE in the follow-up of these patients. The therapeutic implications are the need for a preventive anticoagulant therapy in the high-risk population receiving Sd HT diagnosed with TEE and the consideration of Tot HT as a better surgical approach as far as thrombotic complications are concerned.

Adult↗
PubMed1995

More rapid, complete, and stable coronary thrombolysis with bolus administration of reteplase compared with alteplase infusion in acute myocardial infarction. RAPID Investigators.

BACKGROUND: Early restoration and maintenance of normal (TIMI 3) blood flow during acute myocardial infarction is critical for optimal preservation of left ventricular function and survival. Recombinant plasminogen activator (r-PA, reteplase) is a nonglycosylated deletion mutant of wild-type tissue-type plasminogen activator (TPA) that has been shown to achieve more rapid and complete thrombolysis compared with other plasminogen activators in animal models. METHODS AND RESULTS: The RAPID Trial was designed to test the hypothesis that bolus administration of one or more dosage regimens of r-PA was superior to standard-dose alteplase (TPA) in achieving infarct-related artery patency 90 minutes after initiation of treatment. Six hundred six patients with acute myocardial infarction were randomized to one of four treatment arms: (1) TPA 100 mg i.v. over 3 hours, (2) r-PA as a 15-MU single bolus, (3) r-PA as a 10-MU bolus followed by 5 MU 30 minutes later, or (4) r-PA as a 10-MU bolus followed by 10 MU 30 minutes later. Coronary arteriography was performed at 30, 60, and 90 minutes after initiation of treatment and at hospital discharge. The 10 + 10-MU r-PA group achieved better 90-minute and 5- to 14-day TIMI 3 flow (63% [CI, 55% to 71%] versus 49% [41% to 57%], P = .019, and 88% [82% to 94%] versus 71% [63% to 79%], P < .001, respectively) than the TPA group. The TIMI 3 flow in the 10 + 10-MU r-PA group at 60 minutes was equivalent to that in the TPA group at 90 minutes (51 versus 49%). Global ejection fraction and regional wall motion in the 10 + 10-MU r-PA group were superior to those of the TPA group at hospital discharge (53 +/- 1.3% versus 49 +/- 1.3%, P = .034; -2.19 +/- 0.12 versus -2.61 +/- 0.13 SD per chord, P = .02, respectively). The 15-MU and 10 + 5-MU r-PA patency and left ventricular function results were similar to those of the TPA and inferior to those of the 10 + 10-MU r-PA group. Bleeding complications were similar between the groups. CONCLUSIONS: r-PA given as a double bolus of 10 + 10 MU achieves more rapid, complete, and sustained thrombolysis of the infarct-related artery than standard-dose TPA, without an apparent increased risk of complications. This was associated with improved global and regional left ventricular function at hospital discharge.

Coronary Angiography↗
PubMed1995

[Neurologic accident of decompression: a new indication of transesophageal echocardiography].

Decompression sickness in a 33-year-old SCUBA diver led to neurological lesions with brain damage. The existence of a patent foramen ovale detected with a transoesophageal contrast echocardiography suggested paradoxal gas embolism. This observation emphasizes the intest of transoesophageal contrast echocardiography in decompression sickness as discussed in the literature. Its widely utilization would permit a better understanding of the pathophysiology of decompression sickness. It also may help the physician in deciding whether or not to authorize further diving.

Adult↗
PubMed1995

Assessment of aortic regurgitation severity by magnetic resonance imaging of the thoracic aorta.

A new method of assessing the severity of aortic regurgitation severity by magnetic resonance imaging has been developed. Two groups were studied: 20 controls (age = 58 +/- 19 years) without valvular aortic disease, and 24 patients (age = 62 +/- 13 years) with chronic aortic insufficiency evaluated by magnetic resonance and aortic root cineangiography within 1 week of each other. A magnetic resonance sequence (TR = 35 ms/TE = 12 ms/flip angle = 20 degrees/magnet = 1.5 T) was acquired in a plane containing the thoracic aorta. A transverse saturation band 30 mm wide was positioned 30-40 mm above the aortic valve. Aortic insufficiency was graded; the importance of end-diastolic retrograde movement in the saturation band in the descending aorta was noted. Magnetic resonance was also compared to Doppler echocardiography in 20 patients. In the controls, we found that retrograde blood flow was absent (18/20) or mild (2/20). In contrast, the presence of marked retrograde movement in a saturation band across the thoracic aorta was always associated with severe aortic regurgitation (angiographic grade III or IV). This rapid method (imaging time less than 20 min) can be applied in most patients with aortic regurgitation and is likely to be helpful when echocardiography is not possible or gives inconclusive results.

Adult↗
PubMed1994

[Cerebral infarction in patients aged 16 to 35 years. Prospective study of 52 cases].

OBJECTIVES: Aetiologies of cerebral ischemic events in young adults are various and often contraversial: atherosclerosis plays a role after age 35 years, cardioembolism is often recognized as the major cause, and numerous new predisposing conditions have been described. To evaluate very premature cerebral infarction, we studied prospectively 52 consecutive patients (34 women and 18 men) aged 16-35 years (mean 28.6 +/- 5.6 years) admitted over a 6-year period for an arterial cerebral infarct identified on CT, on MRI or both. METHODS: All patients were investigated using a standard protocol including cerebral angiography, transthoracic echocardiography, 24-hour Holter ECG monitoring, coagulation inhibitors levels, lupus anticoagulant testing, HIV and syphilitic serologies. Additional investigations were performed in a majority of patients: transesophageal echocardiography in 33, contrast echocardiography in 50, and anticardiolipin antibodies levels in 38. RESULTS: The arterial distribution of infarction did not differ from that of overall stroke patients. Sixteen cases were classified as certain aetiologies, including cardiac diseases with high embolic risk (n = 9), spontaneous arterial dissection (n = 4), moya-moya disease (n = 1), atherosclerosis (n = 1), and inherited antithrombine III deficiency (n = 1). Eighteen cases were classified as possible aetiologies including cardiac diseases with low embolic risk (n = 11) such as mitral valve prolapse or atrial septal aneurysm, miscellaneaous arteriopathies (n = 3) such as arterial dysplasia, antiphospholipid antibodies syndrome (n = 1) and migrainous stroke (n = 3). The 18 last cases were classified as unknown aetiologies, despite all patients but one had at least one vascular risk factor: this group significantly differed from the formers in that the patients were more frequently women using oral contraceptive associated with tobacco consumption, hypercholesterolemia, or both. Two patients died acutely and the survivors were followed 31 +/- 18 months. Three patients experienced recurrent stroke. Functional outcome was assessed using the Rankin scale on admission and 6 to 12 months after the onset of stroke: patients evaluated < or = 2 (no to mild handicap) were 31% on admission and 82% after recovery. Twenty six p. cent remained unable to resume a work. CONCLUSION: Despite extensive evaluation, identification and classification of aetiologies of cerebral infarction in young adults should be cautious because the risk as well as the pathogenesis of many potential causes still need to be defined.

Adolescent↗
PubMed1994

Valproic acid intensifies the depressant action of phenobarbital and ethanol by a pharmacodynamic mechanism.

This investigation was designed to determine whether valproic acid (VPA) affects the pharmacodynamics of the depressant action of phenobarbital (PB) and ethanol. Rats received sodium valproate iv, 150 mg/kg, or saline, followed 20 min later by a constant infusion of either PB or ethanol until onset of anesthesia. At that time the concentrations of the depressant drugs in biological fluids were determined. In order to induce anesthesia, VPA-treated rats required significantly lower PB total serum concentrations (36% reduction) as well as lower PB cerebrospinal fluid concentrations (20% reduction). Similarly, the ethanol dose required to induce onset of sleep was about 35% lower, and the serum ethanol concentrations at that endpoint were 44% lower in the VPA-treated group as compared to corresponding controls. These results indicate that VPA accentuates the effect of the depressant action of ethanol and PB on the central nervous system.

Animals↗
PubMed1994

Prolonged wall motion abnormalities after chest pain at rest in patients with unstable angina: a possible manifestation of myocardial stunning.

Although myocardial "stunning" would be expected to occur in unstable angina, there is no published report in which the recovery of regional left ventricular function was serially monitored in this syndrome. To determine whether the time course of the regional wall motion abnormalities associated with unstable angina is consistent with myocardial stunning, 20 consecutive patients with unstable angina were studied prospectively. Regional left ventricular wall motion was assessed by two-dimensional echocardiography during or immediately after angina at rest and at serial times thereafter. Six of the 20 patients fulfilled the inclusion criteria. The recovery of segmental wall motion after chest pain was consistently found to be delayed in all six patients, but a considerable variability was observed. In at least two subjects, the improvement was rapid and the wall motion abnormalities disappeared almost completely within 2 hours after the chest pain. Both of these patients had the shortest duration of angina (approximately 10 minutes). In contrast, in three other patients with longer duration of chest pain, the improvement was slower and significant wall motion abnormalities were still present at 24 hours after the chest pain. In five control patients who had angiographically-documented coronary artery disease but no recent episode of angina, there was no significant change in segmental wall motion during a period of observation equivalent to that used in the unstable angina group. This study evaluated for the first time the time course of wall motion abnormalities in patients with unstable angina. The results demonstrate that angina at rest is followed by a prolonged depression of contractile function, which may persist for up to 24 hours or even longer. Because none of the patients had evidence of acute myocardial infarction or recurrent ischemia, our observations suggest myocardial stunning as the pathophysiologic substrate for the slow recovery of wall motion. The present results are consistent with the concept that myocardial stunning does occur in unstable angina and indeed may be a component of the natural history of this disorder; however, further investigations using simultaneous measurements of function and flow will be necessary to unequivocally distinguish myocardial stunning from hibernation and silent ischemia.

Angina, Unstable↗
PubMed1994

The effect of immunosuppression by total-body irradiation on the pharmacodynamics of centrally active drugs in rats.

The aim of this investigation was to assess whether immunosuppression induced by total-body irradiation (TBI) affects the pharmacodynamics of centrally acting drugs. Female Sabra rats were exposed to a single dose of gamma irradiation (5.3 Gy). Four days later, when both the cellular and the humoral immune responses were impaired, they received an i.v. infusion of either phenobarbital (0.8 mg/min), ethanol (16.3 mg/min), pentylenetetrazol (PTZ; 0.618 mg/min), or theophylline (as aminophylline; 2 mg/min). The infusion was stopped at the onset of the pharmacologic end point--loss of righting reflex for the depressant agents or maximal seizures for the stimulant drugs--and the concentrations of the neuroactive drugs at that point were determined. In the ethanol experiment, blood samples were also taken upon awakening. The radiation-induced immunosuppression significantly decreased the CNS sensitivity to the depressant action of both phenobarbital and ethanol as indicated by the higher CSF phenobarbital concentrations required to induce sleep in the irradiated rats versus controls (156 +/- 4 vs 133 +/- 5 mg/L, respectively; P < 0.05), and the higher serum ethanol concentrations at the onset and offset of sleep in the immunosuppressed group versus control values (4.6 +/- 0.2 and 1.68 +/- 0.01 vs 3.79 +/- 0.17 and 1.32 +/- 0.9 mg/mL, respectively; P < 0.04). Exposure to TBI did not alter the pharmacodynamics of the two convulsant drugs (theophylline and PTZ).

Animals↗
PubMed1994

Thallium perfusion and myocardial hypertrophy in transplanted heart recipients with normal or near-normal coronary arteriograms.

In patients with hypertrophic cardiomyopathy or systemic hypertension, exercise thallium perfusion defects have been observed but without significant angiographic stenoses. Hypertension and myocardial hypertrophy are common in transplanted heart recipients, and the aim of this study was to determine if exercise thallium scintigraphy false-positives are frequent in transplanted heart recipients. Thirty-four transplanted heart recipients were evaluated by exercise thallium single emission computed tomography and subsequently had a normal or near normal coronary arteriogram. At the time of the exercise, the patients (28 men and six women) had a mean age of 48.9 +/- 12 years and 29 had been previously treated for systemic hypertension. The mean duration between transplantation and the exercise test was 31.6 +/- 13 months. In all patients left ventricular mass was obtained by echocardiography within 3 months of thallium 201 SPECT and was > or = 130 g.m-2 in nine males and > or = 110 g.m-2 in four females. M-mode septal + posterior end-diastolic thickness was > 23 mm in 14 patients, all of whom had been previously treated for systemic hypertension. These patients were older and endured a longer period during which the heart was kept cold but ischaemic before being grafted ('cold ischaemia') but a shorter exercise duration than patients without left ventricular hypertrophy. During exercise testing, 26 of 34 patients achieved at least 80% of their maximal predicted heart rate and two developed significant ECG changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Hyperhomocysteinaemia in heart transplant recipients.

The aim of this study was to determine the prevalence of hyperhomocysteinaemia in cardiac transplant recipients. Three groups of subjects were studied: 27 heart transplant recipients, 14 to 63 months (mean = 36.5) after transplantation; 10 patients with moderate chronic renal insufficiency without clinical evidence of vascular disease; 17 apparently healthy individuals. Twenty-five out of 27 transplanted patients had a coronaroangiography within 6 months of homocysteine measurement. Plasma homocysteine was measured both while the subject was fasting (t0) and 6 h after administration of 0.1 g.kg-1 of methionine (t6). Hyperhomocysteinaemia was present in 14/27 fasting transplanted patients and after methionine loading. Mean plasma levels of homocysteine at t0 were higher (P = 0.03) in transplanted heart recipients (15.4 +/- 7 mumol.l-1) than in the renal patients (9.9 +/- 5 mumol.l-1) despite similar mean plasma creatinin. In eight transplanted patients with angiographic coronary abnormalities of the cardiac graft, homocysteinaemia was at t0 17.1 +/- 9 mumol.l-1 and at t6 47.8 +/- 25 mumol.l-1. In 17 transplanted patients with angiographically normal coronary arteries, plasma homocysteine levels were at t0, 13.2 +/- 4 mumol.l-1 and at t6, 46.8 +/- 25 mumol.l-1. We conclude that hyperhomocysteinaemia is common in transplanted heart recipients, and partly related to renal insufficiency. No correlation was found between hyperhomocysteinaemia and angiographic evidence of coronary atherosclerosis of the graft, but the population of the study was possibly too small to establish this correlation.

Aged↗