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Biomedical subjects

P de Groote

Publications and source records attributed to P de Groote.

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

Kinetics of oxygen consumption during and after exercise in patients with dilated cardiomyopathy. New markers of exercise intolerance with clinical implications.

OBJECTIVES: This study analyzed the kinetics of oxygen consumption during and after a maximal cardiopulmonary exercise test in patients with dilated cardiomyopathy. The prognostic information derived from indexes of recovery was also studied. BACKGROUND: Previous studies have examined the kinetics of oxygen consumption during a short recovery period in a limited number of patients. To our knowledge, no study has examined the prognostic information derived from indexes of recovery. METHODS: We studied 153 patients and 55 control subjects. We calculated the ratio between total oxygen consumption during exercise and recovery, the half-recovery time of peak oxygen consumption, the time constant of recovery, the recovery time and the ratio between duration of exercise and recovery time. RESULTS: Recovery of oxygen consumption was significantly delayed in patients, and this delay was related to the degree of exercise intolerance. After a median follow-up period of 439 days, for the total study group, percent of predicted peak oxygen consumption (p = 0.003) and ejection fraction (p = 0.03) were independent predictors of survival. In a subgroup of patients with moderate exercise intolerance (percent peak oxygen consumption > 40%), the ratio between total oxygen consumption during exercise and recovery (p = 0.013) and the ejection fraction (p = 0.013) were independent predictors of survival. CONCLUSIONS: The kinetics of oxygen consumption during recovery was delayed in patients with dilated cardiomyopathy. Although indexes of recovery were not prognostic markers in the total study group, the ratio between total oxygen consumption during exercise and recovery was an independent prognostic marker in patients with moderate exercise intolerance.

Adult↗
PubMed1996

Prevalence and clinical significance of antiphospholipid antibodies in heart valve disease: a case-control study.

The purposes of this study were (1) to assess the prevalence of antiphospholipid (aPL) antibodies in patients with non-specific heart valve disease referred for valve replacement and (2) to determine whether the presence of aPL antibodies carries a risk for thrombotic events during a postoperative follow-up in a prospective cohort. The sera of 89 consecutive patients and 80 matched control subjects were tested for antibodies to cardiolipin (immunoglobulin G and immunoglobulin M) and for lupus anticoagulant. The prevalence of aPL antibodies was significantly higher in patients (19 [21%] of 89) than in control subjects (7 [9%] of 80) (p < 0.05). Patients were divided into two subgroups according to the presence (subgroup A) or the absence (subgroup B) of aPL antibodies. No significant difference in age or sex ratio was observed between the two subgroups. A history of arterial thrombosis was more frequent in subgroup A (8 [42%] of 19) than in subgroup B (8 [11%] of 70) (p < 0.01). No significant difference with respect to the occurrence of thrombotic events was observed during a median follow-up period of 8.7 months. Thus a high prevalence of aPL antibodies was found in patients referred for heart valve replacement compared with matched control subjects. No increased risk has been demonstrated in the patients with aPL antibodies.

Antibodies, Anticardiolipin↗
PubMed1996

[Value of spiral computed tomography with three-dimensional reconstruction in the investigation of renal arteries. An initial clinical experience apropos of 16 cases].

Renovascular hypertension represents 1 to 2% of all causes of hypertension. It is important to make the diagnosis as radical treatment may be proposed. Digitised arteriography is the reference diagnostic method. Spiral angiotomography is a new diagnostic technique for the investigation of the aorta and its branches. The examination was performed with a Siemens Somatom Plus S spiral scanner. The images were acquired after intravenous injection of 140 ml of iodine contrast medium in the forearm. Three dimensional reconstruction of the renal arteries may be performed secondarily. The results of 16 examinations were compared with those of arteriography. Nine stenoses were suspected after spiral angiotomography and confirmed in 7 cases by arteriography (sensitivity 100%; specificity 77%); two adrenal abnormalities were also detected by spiral tomography. In this series, spiral angiotomography detected all cases of renal artery stenosis with good specificity. Moreover, this investigation also allowed evaluation of the adrenal glands. The simple, non-invasive and polyvalent nature of this method should, if the results are confirmed in a large series, lead to its use as the investigation of first intention for suspected secondary causes of hypertension.

Female↗
PubMed1996

[Acute myocarditis caused by toxoplasmosis simulating infarction. Apropos of a case].

Acute myocarditis due to toxoplasmosis infection has been previously reported, usually in patients suffering from immuno-depression. Cardiac involvement by toxoplasmosis is rare in subjects with a normal immunological status. The authors report the case of a 16-year-old patient without immuno-depression with acute myocarditis caused by toxoplasmosis simulating myocardial infarction.

Acute Disease↗
PubMed1995

Local lesion-related factors and restenosis after coronary angioplasty. Evidence from a quantitative angiographic study in patients with unstable angina undergoing double-vessel angioplasty.

BACKGROUND: Restenosis rates are high when coronary angioplasty is performed in patients with unstable angina. The relative contributions of local and systemic factors to this excess risk of restenosis are unclear. To assess these, we compared changes in minimal lumen diameter and the incidence of restenosis, determined by quantitative coronary angiography, after coronary angioplasty at culprit and nonculprit lesions dilated in the course of a single procedure in patients with unstable angina. METHODS AND RESULTS: We identified 67 consecutive patients with unstable angina in whom two lesions, in different vessels, were dilated during the same procedure. Lesions were designated as culprit or nonculprit on the basis of the location of ECG changes during chest pain combined with assessment of the angiographic characteristics of the lesions. With these criteria, 43 patients had identifiable culprit lesions. Stenosis severity before and immediately after angioplasty and at follow-up was assessed with quantitative angiography. Angiographic follow-up was performed in 91% (39 patients) of this subgroup. Culprit lesions were more severe (P < .02) than nonculprit lesions. The late loss at culprit lesions (0.87 +/- 0.75 mm) was significantly (P < .01) greater than the equivalent value for nonculprit lesions (0.33 +/- 0.69 mm). With a categorical definition (> 50% stenosis at follow-up), restenosis occurred at 67% of culprit lesions and at 32% of nonculprit lesions (P < .01). CONCLUSIONS: The greater loss in minimal lumen diameter and the consequent higher rate of restenosis at culprit compared with nonculprit lesions suggest that local "lesion-related" factors are an important determinant of the high rate of restenosis when coronary angioplasty is performed in patients with unstable angina.

Angina, Unstable↗
PubMed1995

Plasma levels of endothelin-1 at rest and after exercise in patients with moderate congestive heart failure.

Plasma levels of endothelin-1 are increased in patients with severe congestive heart failure related to various etiologies. However, conflicting data have been published in patients with moderate congestive heart failure. Moreover, the effect of exercise on plasma levels of endothelin-1 is not precisely known. We determined the plasma levels of endothelin-1 in a homogenous group of patients with idiopathic dilated cardiomyopathy in stage II of the New York Heart Association functional classification at rest and at peak exercise. In this group of patients, plasma levels of endothelin-1 were increased compared to a control group (2.9 +/- 0.27 vs. 1.96 +/- 0.24 pmol/l, P < 0.01, mean +/- S.E.M.), as were plasma levels of atrial natriuretic peptide (26.3 +/- 6.3 vs. 2.95 +/- 0.7 pmol/l, P < 0.001), plasma renin activity (12.6 +/- 2.98 vs. 1.75 +/- 0.23 ng/ml per h, P < 0.001) and plasma levels of aldosterone (217 +/- 29.3 vs. 154 +/- 18.8 pg/ml, P < 0.05). In contrast to the other hormones, exercise did not increase plasma levels of endothelin-1. There was no correlation between plasma levels of endothelin-1 and plasma levels of atrial natriuretic peptide, and no correlation between left ventricular ejection fraction, peak oxygen consumption and hormonal values. In conclusion, plasma levels of endothelin-1 are increased in a homogeneous group of patients with idiopathic dilated cardiomyopathy and moderate congestive heart failure. Endothelin-1 could participate in the progression of heart failure. Exercise did not increase the plasma levels of endothelin-1 in contrast to the other hormones.

Adult↗
PubMed1995

[Congestive heart failure in the elderly. Value of Doppler echocardiography].

Fifty-eight consecutive elderly patients (seven men and 51 women, mean age 84 +/- 6) admitted for congestive heart failure were prospectively investigated by doppler echocardiography in order to 1) define the prevalence of cardiac failure with normal left ventricular systolic function, 2) estimate the role of abnormalities of left ventricular filling (diastolic dysfunction), 3) evaluate echodoppler parameters for assessment of diastolic function: ratio of early peak on atrial peak of filling velocities (E/A), mitral deceleration time (MDT) and isovolumic relaxation time (IRT). Of the 58 patients, 32 (55%) had normal left ventricular systolic function and 26 (45%) had systolic dysfunction. Of the 32 patients with normal systolic function, diastolic function could not be evaluated in nine patients, was abnormal in 16 and normal in seven. Congestive heart failure with normal systolic function is very frequent in the elderly subject. Sensitivity of clinical data being too low, doppler echocardiography is the easiest noninvasive technique for defining abnormalities of both left ventricular systolic and diastolic function. In the elderly, MDT and IRT are more sensitive parameters than E/A for the diagnosis of diastolic dysfunction.

Aged↗
PubMed1995

Outcome after thrombolytic therapy of nine cases of myopericarditis misdiagnosed as myocardial infarction.

Anecdotal reports have suggested that cardiovascular complications may occur if thrombolytic therapy is performed in cases of pericarditis misdiagnosed as acute myocardial infarction. From 1980 to 1993, 47 cases of myopericarditis mimicking myocardial infarction have been admitted to our institution. The misdiagnosis was made because of clinical onset characterized by a typical chest pain, and/or localized ST segment elevation. Since 1987, nine (9/9 males, age 40 +/- 14 years) out of the 47 patients (19%) have been treated with a thrombolytic agent (streptokinase 4/9, rt-PA 5/9) followed by intravenous heparin. This treatment was started during the pre-hospital phase (2/9) and while in hospital (7/9). No pericardial rub was present; ST segment elevation was mainly localized in inferior and lateral leads; no Q wave developed; median creatine kinase rise was 268 units (range 38 to 1280), and only one patient had a small pericardial effusion. The mean level of fibrinogen after thrombolysis was 1.72 g.l-1 (range 0.10 to 4.50). In all cases, typical ECG changes were present suggesting pericarditis with a subsequent return to a normal ECG. No severe cardiac or pericardial complication or arrhythmia occurred; only one patient developed a non-compressive and resolvable pericardial effusion. Cardiac catheterizations (coronary and left ventricular angiographies) were normal when performed (5/9). Long-term follow-up (mean 46 +/- 29 months) was favourable without any coronary events. In conclusion, thrombolytic therapy was uncomplicated in our patients with myopericarditis simulating evolving myocardial infarction.

Adolescent↗
PubMed1995

Comparative diagnostic value of ankle-to-brachial index and transcutaneous oxygen tension at rest and after exercise in patients with intermittent claudication.

BACKGROUND: Few studies have compared sensitivities of ankle-to-brachial index (ABI) and transcutaneous oxygen tension (TcPO2) in a large group of patients with Leriche stage II intermittent claudication. METHOD AND RESULTS: 111 patients (138 limbs) with a stable chronic (> three months) intermittent claudication and significant peripheral vascular disease (PVD) proved by angiography were studied. They performed a treadmill test (10%, 3 km/hr) limited by limb pain. ABI and TcPO2 were measured before, just after exercise, and after three and ten minutes of recovery in supine position. Sensitivities per patient for ABI and TcPO2 were respectively at rest: 82.9% and 28.8%, and after exercise: 88.3% and 62.2%. Sensitivities per leg (n = 138) for ABI and TcPO2 were respectively at rest: 73.9% and 26.8%, and after exercise: 82.6% and 34%. The sensitivity of TcPO2 increased to 56.5% after three minutes of recovery but was always less than that of ABI, which was maximal just after exercise (82.6%). The sensitivity of the regional perfusion index was similar to that of TcPO2. The sensitivity of TcPO2 increased with respect to the Leriche stage and the number of lesions but was always lower than that of ABI. There was a weak correlation between TcPO2 and ABI after exercise, but no correlation was noted between maximal walking distance, ABI, and TcPO2. CONCLUSION: TcPO2 is not required in patients with Leriche stage II intermittent claudication but might be useful either in severely affected patients (Leriche stage III or IV) or in selected patients.

Aged↗
PubMed1995

[Current respective role of surgery and permanent endocavitary stimulation in the treatment of hypertrophic cardiomyopathies].

Surgery and cardiac pacing are the two main non-drug treatments for hypertrophic cardiomyopathy. Various surgical techniques have been proposed over the last 35 years: myotomy, myotomy-septal myomectomy, isolated mitral valve replacement, heart transplantation. Patients eligible for surgery are those with severe symptoms (NYHA stage III or IV) and refractory or no longer responding to drug treatment. The choice between the various techniques is based on morphological and haemodynamic criteria (significant subaortic gradient associated with increased septal thickness, severe and/or organic mitral regurgitation, either isolated or associated with obstruction, or less severe or heterogeneous septal thickness [< 18 mm]) or therapeutic criteria (failure of primary myomectomy, depletion of all surgical possibilities). Analysis of the results of surgery is complicated by the variety of techniques performed and the experience of the various teams. The operative mortality was markedly decreased (between 2 and 11% at the present time); the complications of myomectomy (ventricular septal defect, disturbances of conduction requiring continuous pacing) are still frequent. Intraoperative transoesophageal ultrasonography could help to further decrease the operative risk. Surgery improves functional symptoms and exercise tolerance. This beneficial effect appears to be more marked, more frequent and more lasting than that of medical treatment. Surgical treatment does not ensure permanent cure, as the symptoms related to pathophysiological abnormalities other than intraventricular obstruction (abnormalities of diastolic filling, myocardial ischaemia, arrhythmias) may develop subsequently. No controlled trial has demonstrated a favourable effect on survival. Continuous pacing, introduced more recently, can now be considered to be a therapeutic method in its own right.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Pacing, Artificial↗
PubMed1994

Folding of the mouse hepatitis virus spike protein and its association with the membrane protein.

Coronaviruses are assembled by budding into pre-Golgi membranes. Using different approaches we have demonstrated that the spike (S) protein and the membrane (M) protein of mouse hepatitis virus (MHV) associate to form large complexes. Newly synthesized M was found in these complexes almost immediately after its synthesis, whereas the S protein started to appear in heterocomplexes after 10-20 min. This is consistent with the slow rate of folding of S and with the observation that folding of S preceeds its association with M. While the folding of S involves the formation of multiple disulfide bonds, folding of M is disulfide-independent. This contrast was reflected by the differential sensitivity of the two proteins to reduction with dithiothreitol (DTT). Addition of DTT to the culture medium of MHV-infected cells drastically impaired the folding of S, but not of M. Consequently, the S protein was unable to interact with M. Under these conditions, S stayed in the ER while M was transported efficiently beyond the site of budding to the Golgi complex. We conclude that the association of S with M is an essential step in the formation of the viral envelope and in the accumulation of both proteins at the site of virus assembly.

Biological Transport↗
PubMed1994

Response of atrial natriuretic factor to surgical pericardial drainage in patients with chronic pericardial effusion.

Previous studies have demonstrated the importance of atrial transmural pressure in the secretion of atrial natriuretic peptide. These studies have been performed in patients with pericardial effusion and hemodynamic compromise. The response of atrial natriuretic peptide to the drainage of chronic pericardial effusion without clinical evidence of tamponade is unknown. We studied 13 patients with chronic abundant pericardial effusion but without hemodynamic compromise. Blood samples for hormonal determinations were drawn before and after surgical pericardiocentesis. Right atrial pressure was measured during the procedure. Drainage induced a significant increase of atrial natriuretic peptide (from 12 +/- 3.9 to 105 +/- 22.8 pmol/l, P < 0.001, mean +/- S.E.M.), correlated with the fall in right atrial pressure (from 7.65 +/- 1.18 to 4.31 +/- 1.46 mmHg, P < 0.05, r = 0.68, P = 0.01). This increase was inversely correlated with the rise of mean blood pressure after surgery (from 84 +/- 2.37 to 100 +/- 5.3 mmHg, P < 0.05, r = 0.65, P < 0.02). Plasma renin activity decreased after drainage (from 8.12 +/- 2.57 to 3.27 +/- 0.65 ng/ml/h, P < 0.05). Surgery induced an increase of plasma levels of aldosterone (from 811 +/- 241 to 1199 +/- 249 pmol/l, P < 0.05), which were reduced after pericardiocentesis (371 +/- 102 pmol/l, P < 0.02). In patients with chronic abundant pericardial effusion, surgical pericardiocentesis induced a significant increase of atrial natriuretic peptide, correlated with a fall in right atrial pressure. The increase of atrial natriuretic peptide was similar than in patients with tamponade, despite a moderate fall in right atrial pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Intermittent left bundle branch block revealed during anaesthesia.

Intermittent left bundle branch block is uncommon. During anaesthesia,, left bundle branch block may be related to hypertension or tachycardia and its occurrence makes the diagnosis of acute myocardial ischaemia or infarction difficult. Patients with intermittent left bundle branch block often develop established left bundle branch block, which may represent an earlier state of ischaemic heart disease. Cardiological investigation of our patient after operation did not point towards an organic cause of intermittent left bundle branch block.

Aged↗
PubMed1994

Treatment of recurrent pericarditis with colchicine.

Corticosteroid therapy, because of its frequent and severe side effects should be avoided if possible, and colchicine may be an effective substitute in steroid-dependent recurrent pericarditis. The aim of our study was to assess the usefulness of colchicine in recurrent pericarditis before initiating corticosteroid treatment. Nineteen consecutive patients (10 males, nine females, age 46 +/- 7 years) with recurrent pericarditis (two episodes or more) were included in this prospective open-label study. Before the study, the patients suffered a total of 57 episodes of pericarditis (mean = 3.0 +/- 0.5 episodes.patient-1) despite the use of non-steroidal anti-inflammatory drugs. The mean interval time between the episodes was 7.3 +/- 5.3 months. Colchicine was given at a loading dose of 3 mg and a maintenance dose of 1 mg daily (for 1 to 27 months (mean = 7.7). During the clinical follow-up, the efficacy was estimated by the occurrence of new episodes of pericarditis and by the need for corticosteroid treatment. No recurrence occurred in 14 out of the 19 patients (74%) during a follow-up of 37.4 +/- 6.5 months. In four out of the 19 patients (21%), five recurrences occurred, which resolved without corticosteroids. Follow-up at 23.8 +/- 12.7 months was free of further recurrence. Only one patient (5%) had several recurrences and required corticosteroids for chronic rheumatism. Tolerance was good except for two cases of diarrhoea, one case of hypothyroidism due to associated long-term antidiarrhoeal therapy (containing iodine), and one case of mild leucopenia.(ABSTRACT TRUNCATED AT 250 WORDS)

Colchicine↗
PubMed1994

Long-term follow-up after peripheral and coronary angioplasty in patients undergoing both types of procedure.

Restenosis rates after peripheral and coronary angioplasties have been assessed only in patients who had either peripheral angioplasty or coronary angioplasty but never in patients who had both types. Among the 6364 angioplasties performed in the authors' institution since 1980, they studied 38 patients (36 men, 2 women, mean age fifty-five years, range thirty-four to seventy-seven) who had both peripheral and coronary angioplasty. The peripheral angioplasties were most often performed on iliac artery stenoses. They were performed before coronary angioplasty in 22 patients (58%) and after coronary angioplasty in 16 patients (42%). The follow-up after peripheral angioplasty was based on clinical data; ultrasound investigation was performed when the result of the clinical follow-up was poor (maximal walking distance lower than 500 meters). Follow-up after coronary angioplasty was assessed by a systematic coronary angiography at six months and with long-term clinical follow-up. The mean durations of the follow-up after peripheral or coronary angioplasty were not significantly different (respectively fifty-six +/- eleven and forty-two +/- nine months [mean +/- 2 SEM]). No patient was lost to clinical follow-up; 17 (45%) ultrasound investigations, 12 (32%) peripheral angiographies, and 34 (89%) coronary angiographies were performed. The restenosis rate after peripheral angioplasty was 18% and that after coronary angioplasty was 34%. These rates are similar to the classic rates observed in the literature. In conclusion, as reported for either procedure alone, the restenosis rates after peripheral angioplasty and after coronary angioplasty are different when assessed in patients who undergo both types of angioplasty.

Adult↗