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B Letac

Publications and source records attributed to B Letac.

At least 91 records · Page 5Linked to original sources
PubMed1991

[Contribution of the continuity equation for the assessment of mitral valve area in mitral stenosis].

The aim of this study was to evaluate the continuity equation in the quantification of mitral valve area in mitral stenosis, the area being considered as the product of the area of the left ventricular outflow tract multiplied by the ratio of the velocity time integrals of the aortic or pulmonary flow to that mitral flow. The continuity equation was compared to two other echocardiographic methods, planimetry and Hatle's method, and to the results obtained at catheterization using the Gorlin formula in a population of 44 patients with mitral stenosis. All were in sinus rhythm; twelve had Grade I mitral regurgitation and 9 patients had Grade I aortic regurgitation. Excellent correlation were observed between the values obtained by the continuity equation and planimetry (r = 0.91; SEE = 0.19 cm2; p less than 0.001) and Hatle's method (r = 0.87; SEE = 0.20 cm2, p less than 0.001). The correlation with the catheter values were also excellent (r = 0.83; SD = 0.22 cm2, p less than 0.001), better than those observed with Hatle's method (r = 0.73; SEE = 0.27 cm2, p less than 0.001) and very similar to those obtained with planimetry (r = 0.87; SEE = 0.23 cm2, p less than 0.001). The sensibility and specificity of the continuity equation for the diagnosis of severe mitral stenosis (surface less than 1.5 cm2) were 90% and 100% respectively, when those of Hatle's method were 88% and 91% respectively. The continuity equation in the evaluation of mitral valve area in mitral stenosis seems to be reliable and accurate compared with catheter data, and superior to Hatle's method.

Echocardiography, Doppler↗
PubMed1990

[Aneurysm of the membranous ventricular septum. Apropos of 4 cases surgically treated].

Four patients with aneurysms of the membranous ventricular septum were operated either because of complications or for associated malformations. The authors describe the anatomical, radiological and, above all, the echocardiographic and angiographic features of this malformation. Surgical management is necessary in complicated cases or when there are associated congenital malformations. The information provided by echocardiography in the diagnosis and follow-up of ventricular septal defects indicates that this malformation is not as rare as was previously thought.

Adolescent↗
PubMed1990

[Percutaneous valvotomy in the combination of mitral and tricuspid valve stenosis. Report of 3 cases].

The authors report the results of a series of 3 cases of double valvuloplasty with a balloon catheter in young patients with combined mitral and tricuspid stenosis. Haemodynamic and Doppler echocardiographic evaluation after the procedure showed comparable results to those of surgical commissurotomy without significant secondary valvular regurgitation. Clinical and echocardiographic follow-up showed that valvular opening remained satisfactory in the 2 cases examined. Percutaneous valvuloplasty would seem to be a valuable alternative to surgical commissurotomy in selected patients with combined mitral and tricuspid valve stenosis.

Adolescent↗
PubMed1990

[Immediate and one-year evaluation of the benefit of aortic valvuloplasty in aortic stenosis with impaired ejection fraction].

Seventy-two consecutive patients with severe aortic stenosis and impaired by left ventricular ejection fractions (EF less than 40%) underwent percutaneous aortic valvuloplasty between September 1985 and November 1987. Forty-five patients had been turned down by the surgeons because of their age (29 patients over 80 years of age), their impaired left ventricular function or associated pathologies. Valvular dilatation with 15 to 23 mm diameter balloons resulted in a reduction of the transvalvular pressure gradient from 63 +/- 21 to 26 +/- 11 mmHg (p less than 0.001) and an increase in valve surface area from 0.48 +/- 0.15 to 0.91 +/- 0.32 cm2 (p less than 0.001) but with large individual variations. No cases of aggravation of associated aortic insufficiency were observed after the procedure. One 98-year old woman died during the dilatation and 4 other patients died during the hospital period. Immediate clinical improvement was observed in 80 per cent of patients. During the one-year follow-up period, 33 patients died, 31 of cardiac causes. Of the 34 survivors at one year, 21 had maintained their clinical improvement. A repeat hemodynamic study was performed in 22 patients 7 months after valvuloplasty. Eleven patients had restenosed and their hemodynamic parameters had practically returned to pre-valvuloplasty values. The left ventricular ejection fractions of the 11 patients without restenosis had increased from 28 +/- 7 to 40 +/- 18 per cent (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1990

[Percutaneous aortic valvuloplasty as a last resort in patients with critical aortic valve stenosis].

Emergency aortic valvuloplasty was performed as a last resort in 34 patients with an average age of 76 years with critical aortic stenosis in the terminal stages with congestive cardiac failure or cardiogenic shock. Emergency aortic valve replacement was considered to be too risky in these cases. The valve was dilated in all patients, resulting in a fall in mean peak-to-peak pressure gradients from 59 mmHg to 21 mmHg and an increase in valve surface area from 0.42 cm2 to 0.85 cm2. Significant improvement in myocardial function was observed immediately after the procedure with an increase of the cardiac index from 1.77 l/min/m2 to 2.07 l/min/m2 and of the ejection fraction from 28% to 35%. Complications were rare. There were no deaths or cerebrovascular accidents during the valvuloplasty procedure. Two patients died in hospital (6%) after the dilatation and two other patients who had persistent pulmonary oedema, underwent surgery; one died and the other had a good surgical result. A clear cut clinical improvement was obtained in the other 30 patients. The patients were followed up for an average of 15 +/- 7 months during which 15 died (50%), 6 +/- 5 months after dilatation. The other 15 survivors have a significant and unhoped for functional improvement. Three young patients later underwent surgical valve replacement in good clinical conditions with the same operative risk as that of standard candidates for aortic valve surgery. One other patient was operated on successfully during another relapse of cardiac failure. These results show that aortic valvuloplasty may be undertaken with a low risk even in the most critical clinical situations and that the procedure rapidly relieves the invalidating symptoms. It may be used as a bridge to surgery in patients with an unacceptable operative risk. The indications should be very flexible in young patients in terminal cardiac failure with cardiogenic shock or refractory pulmonary oedema.

Aged↗
PubMed1990

Coronary venous synchronized retroperfusion during percutaneous transluminal angioplasty of left anterior descending coronary artery.

Synchronized coronary venous retroperfusion was applied and studied in 16 patients undergoing percutaneous transluminal coronary angioplasty (PTCA) balloon dilatation of proximal left anterior descending (LAD) coronary artery stenosis. The rationale for using retroperfusion support during the PTCA-induced coronary artery occlusions was to ameliorate or prevent myocardial ischemia and possibly facilitate extension of the PTCA balloon-inflation period. After therapeutic PTCA treatment, which successfully dilated the culprit coronary artery in all 16 patients, and a 5-minute recovery period, a single retroperfusion-treated LAD occlusion (101 +/- 36 seconds) was compared with equivalent untreated control LAD occlusions (86 +/- 24 seconds) before and after the retroperfusion-supported balloon occlusion. Observations and measurements encompassed 1) ease and time of coronary sinus catheterization, 2) incidence of anginal pain during LAD occlusion, 3) electrocardiographic signs of myocardial ischemia, and 4) two-dimensional echocardiographic indexes of global left ventricular function. The coronary sinus was successfully catheterized within 139 +/- 140 seconds, and in 12 of the 16 patients, the tip of the special autoinflatable retroperfusion balloon catheter could be placed in the desired location of the great cardiac vein. The retroperfusion protocol interfered minimally with the PTCA procedure, and application of the support system had no deleterious effects. As compared with the pain reported 23 (72%) times during the 32 control LAD occlusions, only five (31%) of the patients indicated pain or discomfort during the retroperfused occlusions. Treated occlusions exhibited delayed or significantly lower electrocardiographic ST segment elevations (sum, 10.4 +/- 7.8 mm) as compared with the controls (sum, 16.2 +/- 7.9 mm and 18.8 +/- 10.6 mm; both p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Balloon catheter therapy and cardiac valvular disease.

Over the last five years, percutaneous balloon dilatation has been developed as a nonsurgical treatment of stenotic cardiac valves in children and adults. In this paper, we review the state of the art in this new and evolving field of interventional cardiac catheterization.

Angioplasty, Balloon↗
PubMed1989

Percutaneous balloon valvuloplasty in patients with severe aortic stenosis and low ejection fraction. Immediate results and 1-year follow-up.

The efficacy, morbidity, and 1-year follow-up of balloon aortic valvuloplasty in patients with low ejection fraction (less than 40%) were studied on a consecutive series of 55 patients (mean age, 77 years) treated from September 1985 to February 1987. Because of their age (20 patients greater than 80 years old), poor left ventricular function, and associated diseases, 45 patients were definitely not surgical candidates. Balloon dilatation with 15-23-mm diameter balloon catheters decreased the transvalvular gradient from 66 +/- 24 to 28 +/- 14 mm Hg (p less than 0.001) and increased the valve area from 0.47 +/- 0.15 to 0.83 +/- 0.27 cm2 (p less than 0.001). Immediately after dilatation, ejection fraction mildly increased from 29 +/- 7% to 34 +/- 9% (p less than 0.001) in 38 patients who had undergone a second left ventricular angiogram after dilatation. No significant change in the degree of aortic regurgitation was found after the procedure. Three patients died in hospital (femoral arterial complications in two, septicemia in one). Immediate clinical improvement was noted in 80% of the patients. During the follow-up (mean, 11 months), 22 patients died (heart failure in 15 patients, sudden death in five patients, myocardial infarction in one patient, cancer in one patient). Thirty patients survived, 21 with persistent clinical improvement. Repeat cardiac catheterization was performed at 6 months in 20 patients, of whom eight had recurrence of symptoms. Nine patients had restenosis: their hemodynamic indexes had returned to prevalvuloplasty values.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

Aortic stenosis in elderly patients aged 80 or older. Treatment by percutaneous balloon valvuloplasty in a series of 92 cases.

Very elderly patients with severe aortic stenosis will probably benefit from percutaneous balloon valvuloplasty. Ninety-two patients, aged 80 or older (mean age, 84 +/- 3.7 years) and all severely incapacitated (18 with an associated pathologic condition or in critical condition with terminal heart failure), underwent a valvuloplasty procedure. Femoral access was used in all cases except seven (8%), in whom the femoral route had to be abandoned and the brachial approach was used due to severe arterial tortuosity. Peak-to-peak ventriculoaortic gradient decreased from 71 +/- 27 to 27 +/- 15 mm Hg, and the aortic valve area increased from 0.48 +/- 0.16 to 0.91 +/- 0.35 cm2 (p less than 0.01). Thirty-two percent had a postprocedure aortic valve area more than or equal to 1 cm2. The final valve area was less than or equal to 0.7 cm2 in 30% of the patients. There were three deaths (ages, 82, 92, and 98 years) in the procedure room. One stroke occurred 1 day after the procedure. Hematoma or thrombosis at the femoral puncture site was observed in 14 cases (15%), requiring surgical repair in only five cases. Three patients died in the hospital; the total in-hospital mortality was 6.5%. Among the 62 patients about whom information could be obtained at a mean follow-up interval of 13 +/- 5 months, there were 18 late deaths (mean age, 85 +/- 11 years). The majority of the surviving 44 patients experienced marked symptomatic improvement. The results indicate that balloon valvuloplasty can be offered to very elderly patients with severe aortic stenosis and can produce improvement in hemodynamic and clinical status.

Aged↗
PubMed1989

[Treatment of acquired aortic stenosis in adults by percutaneous valvuloplasty with balloon catheterization. Experience of 245 cases].

In our department, percutaneous balloon valvuloplasty has become the routine treatment of aortic valve stenosis in adults. We report here the results obtained in 245 consecutive patients. The patients' age varied between 30 and 98 years (mean 74 +/- 11 years), 77 of them (31 p. 100) being 80 years' old or older. The initial peak to peak ventriculo-aortic gradient was 72 +/- 25 mmHg and the aortic valve area was 0.53 +/- 0.17 cm2. After dilatation the gradient was reduced to 29 +/- 14 mmHg (p less than 0.001) and the aortic valve area was increased to 0.95 +/- 0.33 cm2 (p less than 0.0001). The aortic valve area was increased by 100 p. 100 or more in 83 patients (34 p. 100) and by less than 25 p. 100 in only 17 patients (7 p. 100). The ventricular ejection fraction rose slightly but significantly from 48 +/- 18 p. 100 to 51 +/- 17 p. 100 (p less than 0.01). One patient developed massive regurgitation and had to undergo semi-emergency surgery. The experience acquired and the use of better catheters enabled us to improve these results by almost doubling the number of patients whose aortic valve area became 1 cm2 or more and by reducing by half those whose aortic valve area remained 0.7 cm2 or less. Three patients aged 82, 91 and 98 respectively died, and there was one cerebral vascular accident in the catheterization room. Nine patients (4 p. 100) died in hospital during the following days.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

[A european multicenter and randomized study of APSAC versus streptokinase in myocardial infarction].

In a multicentre randomized open study conducted on two parallel groups the effectiveness of APSAC was compared with that of streptokinase (SK) in 116 cases of myocardial infarction treated during the first 2.75 hours. APSAC (30 IU) was administered by intravenous bolus injection over 2 to 5 minutes, and SK (1.5 million IU) by intravenous infusion over 60 minutes. The patency of the coronary artery responsible for myocardial infarction was evaluated by coronary arteriography performed 1.74 h on average after the beginning of treatment; it was 70 p. 100 in the APSAC group and 51 p. 100 in the SK group (p less than 0.05). The fall in plasma fibrinogen was similar in both groups (mean minimum level; 0.2 g/l). Haemorrhages occurred in 9/58 patients treated with APSAC (15.5 p. 100) and in 13/58 patients treated with SK (22.4 p. 100); these haemorrhages took place during the first 24 hours in 4 patients of the APSAC group and in 10 patients of the SK group. Five patients died: 2 in the APSAC group and 3 in the SK group. In a subgroup of 38 patients who underwent 3 control coronary arteriographies (at 90 min, 24 hours and 3 weeks), the patency rates were 63 p. 100, 82 p. 100 and 93 p. 100 respectively with APSAC and 44 p. 100, 86 p. 100 and 92 p. 100 respectively with SK (NS). No coronary reocclusion occurred in the APSAC group, as against 3 (1 early, 2 delayed) in the SK group. It is concluded that APSAC seems to be more effective than intravenous streptokinase; it is easier to administer (bolus injection) and does not carry a higher risk of haemorrhage.

Anistreplase↗
PubMed1989

[Percutaneous mitral valvuloplasty using balloon catheterization. Immediate results in 80 cases].

In our first 80 attempts of percutaneous double balloon mitral valvuloplasty (BMV) 77 procedures have been successful. The mean patients age was 44 +/- 17 years, there were 16 men; 12 patients had previously been operated, 29 patients had important valvular deterioration (calcifications, thickening or unpliability) or of subvalvar system. For technical failure BMV was performed with only one balloon in 8 patients. BMV resulted in significant improvement in haemodynamic values: the mean capillary pressure fell from 22 +/- 6 to 12 +/- 5 mmHg (p less than 0.001), the mean mitral gradient from 15 +/- 6 to 5 +/- 3 mmHg (p less than 0.001). Cardiac index remained unchanged. The hemodynamic valve area, by Gorlin formula, increased from 1.09 +/- 0.29 to 2.19 +/- 0.72 cm2 (p less than 0.001). Doppler and echocardiography data were similar to haemodynamic data. Mitral valve area obtained with BMV was equivalent to the area usually obtained in closed mitral commissurotomy. There were 3 tamponades. The first, in a patient to whom BMV was not successful. For the 2 others, surgically evacuated, intracavitary pressures were measured after surgical pericardial drain. BMV was of little efficacy in one patient who died 3 days thoracotomy. The three tamponades were caused by straight tip balloon left ventricle perforation. There was no tamponade with pigtail tip catheter balloon. Mitral valve regurgitation was never increased more than 1 + Interatrial septal defect with QP/QS greater than or equal to 1.5 and less than 2 was present in 5 patients. BMV may be a useful alternative to surgery with low incidence of complication. Mitral valve area increase is similar with both treatment.

Adult↗
PubMed1988

Insights on the mechanism of balloon valvuloplasty in aortic stenosis.

An analysis of the mechanisms of action of balloon valvuloplasty in adult aortic stenosis (AS), based on postmortem studies on fresh specimens and on clinical experience with 300 consecutive cases, is reported. When maximally inflated, a 20-mm diameter balloon (occupying a 3.14 cm2 cross-sectional area) significantly enlarges the stenosed valve orifice by 3 mechanisms: stretching of valve tissue, rupturing of commissural fusion and breaking of calcific deposits. These last 2 mechanisms are the most effective, in both tricuspid and bicuspid forms of AS, to render the cusps more flexible and able to open during systole and to close at the time of ventricular diastole. The marked increase in valve area obtained by the dilatation procedure was clearly demonstrated on fresh postmortem specimens and also on postmortem examination of cases that had had balloon valvuloplasty during life. Stretching alone may give only a temporary increase in valve area with an elastic return of the leaflets to their initial stenosing position and may explain, at least in part, the occurrence of restenosis. Inflation of the balloon is well tolerated with no deleterious decrease in blood pressure in two-thirds of the cases because the balloon opens the commissures, allowing blood ejection through these openings. It does not produce calcific emboli, probably because calcium deposits remain imbedded in the leaflets, covered by the endothelium. Finally, it very infrequently produces acute severe aortic regurgitation. Careful choice of balloon size is necessary to obtain on effective opening; most often a 20-mm diameter balloon but sometimes a balloon up to 23 mm is used.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[Percutaneous valvuloplasty using a balloon catheter in acquired mitral and aortic stenosis in adults].

Since 1984 to 1985, catheter dilation of mitral stenosis and aortic stenosis has been added to the arsenal of interventional cardiology. In mitral valvuloplasty the left atrium is approached by transseptal catheterization. Dilation is normally performed by two balloon catheters of 20 mm diameter. One or two dilations of 20 sec duration are usually sufficient to open the mitral valve by cracking one or two fused commissures. In our series of 61 patients the mitral valve area had more than doubled (from 1.03 +/- 0.27 cm2 to 2.17 +/- 0.71 cm2). The most suitable subjects for the technique are young patients in sinus rhythm with relatively elastic valve leaflets, few calcifications, little distortion of the subvalvular apparatus and no major regurgitations. However, mitral valvuloplasty can also be tried in less favourable conditions where there are surgical contraindications, particularly in elderly patients. The complications of the technique are in fact rare. The functional improvement is spectacular and control studies over two years show no tendency to restenosis. --In aortic valvuloplasty a retrograde arterial approach is used. Balloon catheters of increasing size are consecutively employed, starting from 15-20 and even 23 mm diameter. Forceful dilation is needed not only to overcome leaflet fusion but also to compress the valvular structures against the aortic wall to render them more pliable and break the calcifications. --Since September 1985 over 400 patients have undergone valvuloplasty at Rouen with satisfactory overall results.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Results of percutaneous transluminal valvuloplasty in 218 adults with valvular aortic stenosis.

The results of balloon aortic valvuloplasty (BAV) in 218 adult patients with valvular aortic stenosis (AS) are reported. In most cases, 3 transcutaneously introduced balloons of successively increasing size were used. Tolerance was excellent in 64%, whereas a decrease in blood pressure below 60 mm Hg during inflation was observed in 36%. The left ventricular-aortic peak to peak gradient decreased from 72 +/- 25 to 29 +/- 14 mm Hg (p less than 0.001) and the aortic valve area increased from 0.52 +/- 0.18 to 0.93 +/- 0.33 cm2 (p less than 0.001). The final aortic valve area was greater than or equal to 1 cm2 in 69 patients (32%). In only 6 cases (3%) the aortic valve area did not change or increased by less than 10%. A clear improvement in the results was observed with gained experience and better catheters. There was 1 death and 1 stroke in the procedure room, and 3 strokes after BAV. Nine patients died shortly after the procedure. There were local complications (hematoma or thrombosis) at the femoral puncture site in 28 (13%) patients. Clinical follow-up was obtained for 144 patients (mean 8 months). There were 24 deaths. In the 120 remaining cases, symptomatic improvement was good in 84%, with decrease or disappearance of dyspnea, angina or both. This study demonstrates that BAV is feasible in adult AS at a low risk and is able to produce marked clinical improvement in most cases.

Adult↗
PubMed1988

A multicenter double-blind comparative study of rilmenidine and clonidine in 333 hypertensive patients.

The efficacy and acceptability of rilmenidine were studied in a double-blind clonidine-controlled multicenter trial; after a 4-week placebo run-in period, patients with supine diastolic blood pressure (BP) between 95 and 115 mm Hg received as monotherapy either rilmenidine or clonidine over 6 weeks. The initial dose (rilmenidine 1 mg/day or clonidine 0.15 mg/day) was doubled (1 mg or 0.15 mg twice a day, respectively) after 2 weeks if diastolic BP remained greater than or equal to 90 mm Hg. Three hundred and thirty-three patients (mean age 57.8 +/- 0.7 years) with a systolic BP of 170.53 +/- 0.92 mm Hg and a diastolic BP of 101.57 +/- 0.30 mm Hg were randomly divided into 2 homogenous groups (rilmenidine, n = 162 and clonidine, n = 171). All patients taking rilmenidine completed the trial. Seventeen patients taking clonidine (10%, p less than 0.01 vs rilmenidine) were withdrawn because of severe side effects. Systolic and diastolic BP were significantly reduced in both groups at every examination (at 2, 4 and 6 weeks). The mean decreases in supine and erect BP were identical in both groups: systolic BP 19 mm Hg and diastolic BP 12 mm Hg after 6 weeks. BP was normalized (systolic BP less than 160 and diastolic BP less than or equal to 90 mm Hg) in 57% of patients taking rilmenidine and 56% of patients taking clonidine (60% of normalized patients had been taking the single dose in both groups).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Agonists↗