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J Acar

Publications and source records attributed to J Acar.

At least 109 records · Page 6Linked to original sources
PubMed1991

[Mid-term results of heart valve replacement with 2 types of pericardial heterograft. Apropos of 208 cases].

Medium-term results of valve replacement with a pericardial bioprosthesis were analysed in 141 patients receiving an Ionescu-Shiley aortic prosthesis and in 67 patients receiving a Mitroflow aortic (42), mitral (21) or double mitro-aortic (4) bioprostheses. There were 8 deaths in the operative (5.7%) and medium term (56 months) follow-up periods in the Ionescu group and a cumulative survival of 625 patient-years. There were 16 late deaths, 8 of cardiac origin. The 8 year survival and good functional results rates were 71% and 53% respectively. The linear rates of thrombo-embolism, endocarditis, reoperation, valvular dysfunction and regurgitation were 3.5, 1.1, 2.6, 2.7 and 6.1% patient-years. The corresponding figures in the Mitroflow bioprostheses were 0.5, 1.0, 3.1, 3.1 and 5.6% patient-years, but the average follow-up was shorter (36 months) with a cumulative survival of 195 patient-years. These results underline the frequency of primary valve dysfunction the mechanisms of which are: early tear in areas of high mechanical stress and late calcification. However, the hemodynamic profiles of this type of prosthesis are better than those of porcine bioprostheses which make them a valuable alternative in elderly patients operated for calcific aortic stenosis with a small aortic ring.

Actuarial Analysis↗
PubMed1991

Degenerative aortic regurgitation.

In view of the growing incidence of degenerative origin among the aetiologies of aortic regurgitation, we felt it interesting to report our experience of the surgical treatment of such patients. Out of 313 patients operated on for isolated chronic aortic regurgitation between 1974 and 1989, 102 (32.6%) had aortic regurgitation of degenerative origin and form the basis of this study. The patients were divided into group I (n = 48) without aneurysm of the ascending aorta and group II (54 patients) with anulo-aortic ectasia. The first group was further subdivided according to the diameter of the ascending aorta: in group Ia (23 patients) the aorta was normal with a root diameter of less than 40 mm, while in group Ib (25 patients) the aorta was enlarged (root diameter between 40 and 54 mm). There was no statistically significant difference between the pre-operative and operative parameters of patients in groups Ia and Ib. All underwent aortic valve replacement without associated surgery of the ascending aorta. During a mean follow-up of 58 months, five patients from group Ib had aortic dissection and in another three, an ascending aorta aneurysm developed. Reoperation was performed in six cases. No such complications occurred in group Ia. At 6 years, the proportion of patients free from complications related to the ascending aorta was 100% in group Ia vs 63 +/- 6% in group Ib (P less than 0.05). In group II, all the patients underwent aortic valve replacement. The modalities of repair of the ascending aorta differed with time.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

[Detection of thrombosis of the left atrium in mitral valve stenosis. Particular value of transesophageal echography].

This retrospective study assessed the prevalence of left atrial thrombi in mitral stenosis and evaluated the diagnostic value ot the main means of investigation Five hundred and eighty-one patients underwent open heart surgery over a 10 year period. The prevalence of atrial thrombi was 7%, the majority (60%) being located in the left atrial appendage. The sensitivity of transthoracic echocardiography for detecting thrombi in the left atrial cavity was satisfactory (65%) but was very poor for detecting thrombi in the left atrial appendage (4%). The results of invasive investigations (atrial angiography and coronary angiography) are no better. Without any doubt, transoesophageal echocardiography, performed in 101 patients in this series, has transformed these results (sensitivity 83%, specificity 97%). False negatives in this study mainly concerned small thrombi adherent to the atrial wall. Under these conditions, it would seem reasonable to propose transoesophageal echocardiography to all patients with mitral stenosis complicated by an embolic event or for those for whom percutaneous commissurotomy is suggested.

Adolescent↗
PubMed1991

[Dystrophic aortic valve insufficiency].

Although dystrophic aortic regurgitation is considered to be a rare condition, if aortic regurgitation due to cystic media-necrosis which usually presents with annulo-aortic ectasia and regurgitation due to dystrophic aortic valves are included, it becomes a relatively common cause of aortic regurgitation. In the authors' experience of 313 patients operated for pure chronic aortic regurgitation, approximately 30% had dystrophic lesions and this was the second most common cause of aortic regurgitation after acute rheumatic fever. The clinical presentation is variable: excluding annulo-aortic ectasia, the other features of dystrophic aortic regurgitation are less well known. Eighty-nine cases without aneurysm of the ascending thoracic aorta were recensed and analysed in a French Cooperative study. They were divided into two groups with respect to the diameter of the ascending aorta measured by echocardiography. The incidence of late postoperative complications of the ascending aorta was higher in patients with a dilated aorta. The diagnosis of dystrophic aortic regurgitation is easy in patients with an aneurysm of the ascending aorta: in other cases, transoesophageal echocardiography is very useful for evaluating the valvular lesions. Surgical treatment of pure dystrophic aortic regurgitation with an aneurysm of the ascending aorta is well established but the best management of aortic regurgitation associated with only mildly dilated aorta is debatable.

Aorta, Thoracic↗
PubMed1991

[Björk-Shiley-Monostrut prosthesis of the aortic valve. Mid-term development].

From July 84 to June 88, 100 patients underwent an isolated aortic valve replacement by a Monostrut-Björk-Shiley prosthesis. Fifty-one had calcified aortic stenosis, 24% aortic insufficiency, 25% mixed aortic lesions. Pre-operatively, their mean age was 57 years, 68% were male, 46% were in NYHA class II or IV, 43% had angina, all were in sinus rhythm. Operative mortality was 4%. All the survivors were followed-up for a mean period of 22 months (6 to 58) with a cumulative follow-up of 183 patients-years. All patients were placed on a long-term regimen of anticoagulant therapy. Two late deaths occurred (1 myocardial infarction, 1 cerebral hemorrhage). The 4 years survival rate was 94%. Postoperative functional results were excellent. Nearly all patients were asymptomatic. Concerning valve related complications: the 4 years actuarial rate of patients free from thromboembolism, hemorrhage, valve thrombosis, periprosthetic leakage and endocarditis were respectively 97%, 97%, 100%, 100% and 100%. No patient were reoperated on. Valvular function was evaluated by mean transprothetic gradient on echo-doppler (61 cases) and by the calculation of the valvular area with transseptal catheterization (21 cases). For small sizes prosthesis (annulus diameter of 19 or 21 mm), medium size prosthesis (23 or 25 mm), large size prosthesis (27 to 29 mm), mean transprothetic gradient were respectively 16, 10 and 6.9 mmHg and valvular aortic area were respectively 1.5, 1.9 and 2.4 cm2. Mid term results of the Monostrut-Björk-Shiley prosthesis on aortic position are good with a low rate of valve related complications and good hemodynamic results, even with the small valve size.

Actuarial Analysis↗
PubMed1991

[Dystrophic aortic insufficiency: influence of dilatation of the ascending aorta on secondary outcome].

This cooperative study recensed 89 cases of patients operated for aortic regurgitation in whom the dystrophic process was confirmed on anatomical (thin, translucent valves without symphysis, multilation or sclerosis) and histological criteria (mucinous infiltration). They included 81 men (91%) and the average age was 52 +/- 14 years. The valvular degeneration was part of a generalised dystrophy of elastic tissue in 8 patients (6 "formes frustes" of Marfan's syndrome, 2 Lobstein's syndrome). The patients were divided into 2 groups according to the diameter of the ascending aorta measured by echocardiography and/or aortography. In Group 1 (n = 40), the aorta was not dilated (diameter less than 40 mm) whereas in Group 2 (n = 49), the diameter of the ascending aorta was dilated (40-55 mm) but not aneurysmal (loss of parallelism of the aortic walls). The two groups were comparable before surgery with respect to age, sex, functional class, degree of left ventricular dilatation, left ventricular ejection fraction and presence of associated coronary disease). There were no differences in the operative parameters but aortic parietal biopsy (n = 35) revealed clear signs of cystic medianecrosis more often in Group 2 than in Group 1 (14/25 versus 1/10, p less than 0.05). No operative procedure was performed on the ascending aorta during aortic valve replacement. One operative death occurred in each group. After an average follow-up of 4 years, there was a higher mortality in Group 2: the actuarial 7 year survival rate being 74% in Group 1 and 54% in Group 2. This was explained by a higher incidence of ascending aortic complications. Only 1 patient in Group 1 developed an aneurysm of the ascending aorta requiring reoperation compared to 14 patients in Group 2, 8 of whom were reoperated (p less than 0.01). These results suggest that non-aneurysmal dilatation of the ascending aorta in patients with dystrophic aortic regurgitation is a poor prognostic factor because of the high incidence of secondary aortic parietal complications (aneurysm, dissection).

Actuarial Analysis↗
PubMed1990

[Percutaneous mitral valvuloplasty].

Since its introduction as an alternative to surgical commissurotomy, percutaneous mitral valvuloplasty (PMV) has been preformed in a wide range of patients. PMV improves valve function significantly, and provides a final valve area of 2 cm2. The quality of the results is mainly related to valve anatomy. The incidence of complications is relatively low: death 0.5%, severe mitral incompetence 4%, and left to right shunts, as assessed by oximetry 20% of which two thirds disappear during follow-up. As of now, only mid-term follow-up results are available. If the initial result is good, functional improvement occurs in most cases and re-stenosis is rare. On the other hand, secondary surgery is most often necessary in case of poor initial result or severe mitral regurgitation complicating PMV. These favorable results lead us to propose PMV as the first treatment for mitral stenosis with pliable valves. On the contrary, valve replacement remains the main treatment in calcific stenosis, PMV being restricted to particular cases: mild calcification, high surgical risk or even refusal of surgery. Finally, the decision of PMV can only be taken after exclusion of contraindications: left atrial thrombosis, moderate to severe mitral regurgitation.

Adolescent↗
PubMed1990

Atrial natriuretic peptide response to postural changes in patients with left atrial hypertension.

Plasma atrial natriuretic peptide (ANP), cyclic guanosine monophosphate (GMP) and renin activity (PRA) were measured in 13 patients with mitral stenosis 24 h before and 48 h after balloon valvotomy resulting in a fall in LA pressure from 23.4 +/- 2.2 to 10.5 +/- 0.8 mmHg (P less than 0.01). Before treatment, plasma ANP was higher during ambulation (128.1 +/- 18.5 pg ml-1) than in the supine posture (93.3 +/- 15.0 pg ml-1; P less than 0.01) and did not diminish after return to the erect posture (86.4 +/- 14.1 pg ml-1). A physiological response was restored after valvotomy with ANP plasma levels of 49.2 +/- 7.8 pg ml-1 in the initial ambulant period, 63.1 +/- 12.6 pg ml-1 in the supine posture and 44.6 +/- 8.7 pg ml-1 in the final erect posture. Postural variations of cyclic GMP were parallel to those of ANP. In contrast, LA hypertension did not abolish PRA postural response. During the three successive periods of ambulation, supine posture and erect posture PRA was 5.4 +/- 1.0, 2.8 +/- 0.6 and 5.5 +/- 1.2 ng h-1 ml-1, respectively, before treatment, whereas after treatment the values measured were 10.3 +/- 2.9, 2.3 +/- 0.7 and 7.0 +/- 2.5 ng h-1 ml-1 respectively. Variations of plasma ANP, cyclic GMP and PRA in response to postural changes were also studied in 10 healthy volunteers and in 12 uraemic patients with high plasma ANP.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Detection of prosthetic valve thrombosis using 111indium platelet imaging.

The diagnosis of prosthetic valve thrombosis (PVT) may be difficult in cases without valve obstruction. The aim of this study was to evaluate the diagnostic accuracy of 111indium-labelled autologous platelet imaging in the detection of PVT. We studied 41 patients with 45 prostheses, mechanical (37) or biological (8), in the mitral (26) or aortic (19) site. Mean age was 55 +/- 13 years. All these patients experienced one or several thromboembolic events (mean: 2.3 per patient). The mean interval between the last embolic event and indium test (IT) was 32 +/- 25 days. Scintigrams were recorded in two views daily for 5 days. IT showed an abnormal platelet deposition on the prosthetic area in 24 patients. Platelet half-life was 3.8 +/- 1.0 days for patients with a positive IT and 4.6 +/- 0.6 days for those with a negative IT (P less than 0.01). Anatomical data were obtained in 10 cases (surgery nine, autopsy one) 16 +/- 5 days after IT. All these patients had PVT, and IT was positive in eight cases. In the other 31 medically treated patients, recurrent embolism occurred within 12 months after IT in four cases, three of whom previously had a positive test. We conclude that IT is a useful means for detecting PVT.

Aortic Valve↗
PubMed1990

[Value of transesophageal echocardiography. From a preliminary experience of 532 cases].

Transesophageal echocardiography (TEE) was introduced recently in France. The aim of this study was to review the diagnostic value of this technique after 8 months' use in our cardiology department. A total of 532 TEE studies were carried out between April and December 1988 in 396 patients (average age 54 years, range 17 to 89 years) at Tenon Hospital. The failure rate was 1.8 per cent (N = 10), over half of which occurred at the beginning of the operator's experience. TEE was particularly valuable compared with the standard transthoracic approach in the following instances: the investigation of mitral stenosis, especially before percutaneous valvuloplasty (N = 75). A left atrial thrombus was demonstrated in 5 cases by TEE vs none by standard echocardiography. There was also a much higher diagnostic sensitivity for small interatrial shunts (40 vs 6) resulting from transseptal catheterisation. In the preoperative investigation of severe mitral regurgitation (N = 29). The etiology was accurately diagnosed in 29 vs 26 cases, and the mechanism of the regurgitation was correctly classified especially in cases of ruptured chordae (15 vs 6 cases). In endocarditis (N = 26) by the visualisation of abscess of the aortic ring (7 vs 1) and vegetations (19 vs 8). In prosthetic valve dysfunction (N = 65) by the demonstration of primary degeneration of bioprostheses (7 vs 4), perivalvular leaks (10 vs 4) and non-occlusive thrombi of mechanical prostheses (3 vs 0). In cases of intracardiac tumours, dissection of the thoracic aorta and atrial septal defects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Factors influencing survival after surgery of pure non-ischemic mitral insufficiency].

Uni and multifactorial (Cox) statistical analysis of the results of surgery in a series of 247 patients operated between 1969 and 1988 for pure, non-ischaemic mitral regurgitation was undertaken to determine the factors influencing operative and late mortality. All but 3 cases were adults, average age 51 years, and very symptomatic (75 per cent Class III et IV of NYHA Classification). Dystrophic or degenerative lesions were responsible for 53 per cent of cases of regurgitation whilst rheumatic valvular disease was only observed in 30 per cent of cases. Mitral valve replacement was performed in 137 patients (96 mechanical and 41 bioprostheses) and conservative surgery was possible in 110 cases. There were 12 operative deaths (4.9%); the operative risk increased with age and with the practice of valve replacement. Eleven of the 235 survivors (4.7%) were lost to follow-up. During the follow-up period (average 58 months) there were 37 late deaths of which nearly a half were due to left ventricular dysfunction. Multifactorial analysis identified cardiothoracic ratio and atrial fibrillation as predictive factors of late mortality whilst left ventricular ejection fraction and the type of surgery were related to the development of left ventricular dysfunction. The postoperative left ventricular ejection fraction was significantly lower after valve replacement than after valvuloplasty (11 +/- 13% vs 3 +/- 13%; p less than 0.01). These results are therefore in favour of early correction of severe mitral regurgitation by conservative surgery whenever possible.

Adolescent↗
PubMed1990

[Echography in surgical mitral insufficiency. Pathologic diagnosis and provision of the surgical procedure].

The aim of this study was to determine the reliability of preoperative transthoracic and transesophageal echocardiography compared with the surgical findings in pure or dominant severe mitral regurgitation with respect to: the evaluation of the lesions, mechanism and etiology; the provision of the type of surgery (valve replacement or reconstruction); One hundred and fifty patients were divided into two groups: Group I (N = 120) in which preoperative assessment included transthoracic echo-Doppler coupled with color Doppler in the last 32 patients; Group II (N = 30) operated recently who underwent both transesophageal and transthoracic echo-Doppler examination. In Group I, the sensitivity of transthoracic echo in the evaluation of the etiological was 86% overall [100% in rheumatic valve disease (N = 28), 86% in degenerative or dystrophic valves (N = 72), 44% in endocarditis (N = 9), 87% in ischaemic dysfunction (N = 8)]. The echo evaluation of the mechanism of the regurgitation was also reliable with the exception of ruptured chordae in which direct visualisation of the rupture was only possible in 19 of the 64 cases (30%). The type of surgery predicted by echo was practiced in 87% of cases.

Adolescent↗
PubMed1990

[Study of the etiologic mechanism of valvular regurgitation using Doppler echography].

Doppler echocardiography is currently the method of choice for diagnosing and determining the mechanism and etiology of valvular regurgitation. The recent introduction of transesophageal echo coupled with color Doppler has increased the value of these ultrasonic methods. The analysis of the valvular lesion should be particularly precise and accurate in severe mitral insufficiency because of the possibility of surgical valvuloplasty, the indications of which are now much broader than was the case at the beginning of the nineteen eighties.

Aortic Valve Insufficiency↗
PubMed1990

[Frequency and distribution of beta-lactamases in 1792 strains of Klebsiella pneumoniae in France between 1985 and 1988].

In october 1985, 1987 and 1988, all the clinical isolates of K. pneumoniae (respectively 530, 654, 590 strains) were collected in 20 hospitals. The beta-lactamases were identified by analytical isoelectrofocusing and by substrate and inhibition profiles. 76 to 81% of the strains produced only one beta-lactamase: SHV-1 type, pI 7.7 (61 to 65%) or PI 7.1 (14%). The TEM-1 betalactamase (pI 5.4) was produced in 1985 by 21% of the strains, 9% in 1987, and 11% in 1988: TEM-2, pI 5.6 by 2% in 1985-87-88. The extended broad spectrum beta-lactamases, able to hydrolyse amino-thiazol-oximino-beta-lactam antibiotics, TEM or SHV type enzymes (SHV-2, pI 7.7, SHV-3, pI 7.1; SHV-4/CAZ-5, pI 7.8; SHV-5/CAZ-4 pI 8.2; CTX-1/TEM-3, pI 6.3) were also detected: 0.75% of the strain (3 strains) in 1985, 8.4% (55 strains) in 1987, 11% (65 strains) in 1988. These extended broad spectrum beta-lactamases were found in 2 hospitals in 1985, 10 in 1987 and 9 in 1988.

France↗
PubMed1989

Results of percutaneous mitral commissurotomy in 200 patients.

To assess the feasibility and efficacy of percutaneous mitral commissurotomy (PMC), the procedure was attempted in 200 patients with severe mitral stenosis. There were 154 women and 46 men, their mean age was 43 +/- 16 years (range 13 to 79) and 15 were older than 70 years of age. Forty-four had had previous surgical commissurotomy. Forty were in New York Heart Association class II, 152 in class III and 8 in class IV. In regard to valvular anatomy, 67 had calcified valves, 58 had pliable valves and only mild subvalvular disease, and 75 had flexible valves but extensive subvalvular disease. Grade 1+ mitral regurgitation was present in 62 and grade 2+ in 2. In 11 patients the procedure was discontinued because of complications in 3 and technical failure in 8. Six of the 8 technical failures occurred during the first 15 attempts. Effective PMC was performed in 189 patients using 1 balloon in 23 and 2 balloons in 166. After PMC, there was a significant improvement in mean left atrial pressure (21 +/- 7 to 12 +/- 5 mm Hg, p less than 0.0001), mean mitral gradient (16 +/- 6 to 6 +/- 2 mm Hg, p less than 0.0001), cardiac index (2.6 +/- 0.8 to 3.1 +/- 0.8 liters/min/m2, p less than 0.001) and valve area assessed by hemodynamics (1.1 +/- 0.3 to 2.2 +/- 0.5 cm2, p less than 0.0001) and 2-dimensional echocardiography (1 +/- 0.3 to 1.9 +/- 0.4 cm2, p less than 0.0001). No patient died. Embolism occurred in 8 (4%), with no further sequelae. Sixteen (8%) had atrial septal defect detected by oxymetry.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Evaluation by two-dimensional and doppler echocardiography of the results of percutaneous mitral valvuloplasty].

The purpose of this study was to determine the value of two-dimensional echocardiography and doppler ultrasound in the evaluation of the results and mechanism of percutaneous mitral valvuloplasty. The study involved 200 patients (77 p. 100 female) of mean age 43 +/- 15 years (range 13 to 79 years), most of whom were in NYHA class III or IV. The patients were divided into three groups according to the severity of the anatomical lesions. Group I patients (n = 58) had flexible valves and only minor alterations of the subvalvular structures; group II patients (n = 75) had flexible valves but deeply altered subvalvular structures; group III patients (n = 67) had calcified valves. Following valvuloplasty, the mean transmitral doppler gradient fell from 16 to 5 mmHg (p less than 0.0001) and the mitral valve area, as measured by two-dimensional echocardiography, increased from 1 to 1.9 cm2 (p less than 0.00001); the corresponding values at doppler measurement were 1 and 2 cm2 respectively. In patients successfully dilated, two-dimensional echocardiography showed that the mechanism involved was complete opening of one or both commissures. Before dilatation, 68 patients (34 p. 100) had an usually small degree of mitral regurgitation. After dilatation, grade 3/4 mitral regurgitation was observed in 9 patients (4.5 p. 100). The quality of the results obtained depended on the anatomical lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

[Percutaneous valvuloplasty of aortic stenosis in adults. Immediate and mid-term results: apropos of 78 attempts].

Between February, 1986 and October, 1987 percutaneous aortic valvuloplasty was attempted in 78 patients: 25 men (32 p. 100) and 53 women aged from 61 to 89 years (mean 79.5 years). All patients were symptomatic; 9 were in class II, 49 in class III and 20 in class IV of the NYHA classification. The decision to try percutaneous valvuloplasty was determined by the high surgical risk associated with age (over 75 in 87 p. 100 of the patients), poor physiological condition or concurrent pathology, or by refusal of surgery. 70 dilatations could actually be made (90 p. 100) either by the brachial route (n = 39) or the femoral route (n = 18) or the transseptal route (n = 7) or by a combined brachial and femoral route which enabled the double balloon technique to be used (n = 6). The procedure comprised 5.6 +/- 3 inflations and lasted for 58 +/- 29 min. The diameter of the largest balloon utilized was greater than 20 mm in 75 p. 100 of the cases. Dilatation reduced the aortic gradient from 62 to 28 mmHg (p less than 0.001) without altering the cardiac index (2.36 to 2.32 l/min/m2) and significantly increased the aortic valve area from 0.49 to 0.76 cm2 (p less than 0.001). At the end of the procedure the aortic valve area was greater than 0.7 cm2 in 63 p. 100 and greater than 1 cm2 in 14 p. 100 of the patients. Five patients had to be operated upon within the month following dilatation (3 after technical failure, 2 for poor functional results).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗