Search PubMed⌕ Search

Biomedical subjects

C M Duran

Publications and source records attributed to C M Duran.

At least 73 records · Page 4Linked to original sources
PubMed1993

Triple-valve operation in the young rheumatic patient.

Multiple-valve operation for the young rheumatic patient remains a problem. There is a paucity of information on the results of repair versus replacement in this age group. Between July 1988 and December 1991, 242 patients less than 20 years of age underwent a valve operation for rheumatic heart disease at our institution. Twenty-four (9.9%) of them had simultaneous mitral, aortic, and tricuspid valve procedures. The mean age was 14.71 years. All 24 patients were in functional class III or IV preoperatively. Valvar regurgitation was the predominant lesion. Four patients (16.7%) had active rheumatic myocarditis at the time of operation. Valve repair was attempted in the absence of infective endocarditis. Triple-valve repair was possible in 12 patients (50%). The hospital mortality rate was 16.7%. Reoperation was performed after repair in 9 patients (45%) without any deaths. The reason for reoperation was failure of the mitral valve repair in all patients, and the cause was technical in 3 patients, progression or recurrence of rheumatic myocarditis in 5, and endocarditis in 1 patient. The three late deaths (15%) were in patients who had mitral valve replacement. Valve repair was associated with a higher reoperation rate, and replacement of left-sided valves was associated with a higher early and late mortality. In conclusion, although valve repair would be ideal in the young rheumatic patient, multiple-valve repair is associated with a high reoperation rate.

Adolescent↗
PubMed1993

Present status of reconstructive surgery for aortic valve disease.

Most surgical techniques for reconstruction of the aortic valve, although described a long time ago, are now feasible with satisfactory results. The general surgical principles for successful reconstruction, and the operative techniques of annuloplasty, commissurotomy, free edge resuspension, unrolling and thinning, and cusp extension are described. Methods for intraoperative evaluation of the repaired valve are also described. Between August 1988 and April 1992, 166 patients underwent aortic valve reconstruction with a 3.2% hospital and 1.2% late mortality. There were no thromboembolic events in the patients with isolated aortic valve repair. The reoperation rate was 6.5%. Echocardiographic study at last follow-up showed stable results at 4 years maximum follow-up.

Aortic Valve↗
PubMed1993

New prosthetic ring for aortic valve annuloplasty.

Aortic valve repair is recently receiving more attention. To broaden the indications for this procedure a prosthetic annuloplasty ring has been developed and tested in animals. Thirty-two sheep underwent implantation of such a ring in the pulmonary (14) and aortic (18) positions. In the 12 survivors followed for a maximum of 200 days the ring was found epithelialized and free from thrombus. One ring was dehiscent; no haemolysis was detected. It is concluded that a small clinical study is warranted.

Animals↗
PubMed1993

The challenge of valve surgery in a developing population.

Between August 1988 and October 1992, 1,052 patients underwent 1,522 valve procedures in our institution. Their mean age was 32.69 years (range 1-90). The etiology was rheumatic in 724 (68.8%), congenital in 120 (11.4%), degenerative in 99 (9.4%), infective in 58 (5.5%) and ischemic in 17 (1.6%). The mean preoperative functional class (NYHA) was 2.95 and 780 (74.1%) were in sinus rhythm. Repair was possible in 885 (58.1%) valves. The rate of repair versus replacement was 94.5% for the tricuspid, 56.2% for the mitral and 43.6% for the aortic valve. The total hospital mortality was 4.18%. For isolated mitral surgery it was 2.94%, for isolated aortic 4.12% and for isolated tricuspid 15%. Double valve surgery carried a mortality of 3% and triple valve surgery 13%. Hospital mortality for isolated mitral and isolated aortic surgery was lower for repair than for replacement (1.5% vs. 5% and 0 vs. 6.8%). The follow-up was 94.65% complete. The total incidence of embolic events was 2.93% with an actuarial freedom at 48 months of 92.71 +/- 5.35% for repair, 88.22 +/- 6.26% for replacement and 90.31 +/- 5.65% for patients with repair and replacement. Late mortality was 4.5%. The actuarial survival excluding hospital deaths was 94.89 +/- 2.10% for repair, 86.84 +/- 2.84% for replacement and 91.33 +/- 2.73% for the mixed group. The reoperation rate was higher for repair (13%) than for replacement (0.1%). This rate was highest for the rheumatic mitral patients with an age below 20 years (25.2%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

The Ross procedure in a young rheumatic population: early clinical and echocardiographic profile.

The use of pulmonary autografts for aortic valve replacement is nearing its third decade. It is showing promise as a permanent aortic valve with its ability to grow with age. We report our experience of 45 patients with a mean age of 16.89 years over a three year period. Rheumatic heart disease was the cause of aortic valve dysfunction in 38 (84.4%) patients. Sixteen (35.5%) patients also underwent mitral valve repair. Echocardiographic examination revealed early reduction of aortic regurgitation and left ventricular dimensions, which remained stable in the short follow up period. There were no early or late deaths. One patient required reoperation for a regurgitant pulmonary autograft at two years. We conclude that pulmonary autograft transplantation to the aortic root seems to offer a near permanent solution in a young population affected by rheumatic valve disease.

Adolescent↗
PubMed1993

Surgery for organic rheumatic disease of the tricuspid valve.

The paucity of reports on the incidence and management of organic involvement of the tricuspid valve in rheumatic disease led us to carry out this retrospective study. Over a four and a half year period, of the 1052 patients undergoing valve surgery at our institution, 253 (24.05%) required tricuspid surgery. Organic involvement was noted in 115 (45.45%) of these patients. Definitive preoperative diagnosis was feasible by echocardiogram in only 48 (41.73%). Tricuspid regurgitation was present in all patients while detectable stenosis was present in 48 (41.7%). Annular dilatation was seen in 52 (45.2%). Primary repair was possible in 107 patients (93.0%). The reduction in tricuspid regurgitation remained stable at the last follow up in all but seven patients. Nine patients underwent reoperation in this study for failure of left-sided valve repairs, of which five needed reoperation on the tricuspid valve. All the five reoperated tricuspid valves had had dilated annuli at primary surgery. The presence or absence of annular dilatation did not cause any significant difference in early or late mortality. The presence of annular dilatation in the presence of left-sided valve lesions superimposed on organically involved tricuspid valves evokes the possibility of the presence of an organo-functional disease.

Adolescent↗
PubMed1993

Vanishing De Vega annuloplasty for functional tricuspid regurgitation.

Annuloplasty is performed for significant functional tricuspid regurgitation even if it is presumed that in some cases the regurgitation will regress spontaneously after correction of the left-sided lesion. In an attempt to avoid the drawbacks of a permanent annuloplasty, we used a reabsorbable De Vega annuloplasty in a selected group of patients. Of 73 patients with functional tricuspid regurgitation operated on between May 1989 and May 1991, 25 with pulmonary arteriolar resistance below 400 dyne.sec.cm-5 underwent a De Vega annuloplasty with 2-0 polydioxanone suture. The diagnosis of significant functional tricuspid regurgitation (mean 2.74 +/- 1.05) was established by transthoracic color Doppler echocardiography in all patients. The degree of functional tricuspid regurgitation and pulmonary arteriolar resistance were measured with the patients anesthetized. In 16 patients the regurgitation remained severe (3+ to 4+) and in 9 it was moderate (2+). Twenty-three patients had mitral (12 repairs, 11 replacements) and 9 had aortic (4 repairs, 5 replacements) valve operations. The immediate postbypass residual functional tricuspid regurgitation was 0 to 1+ in 23 and 0 in 2. There was 1 (4%) operative death. The maximum follow-up period was 24 months (mean 13.9 months). There were 2 (8.3%) late deaths. Six patients underwent reoperation because of mitral dysfunction. Four of them who were reoperated on between 2 and 5 weeks after the initial procedure showed no recurrence of functional tricuspid regurgitation. The other 2, reoperated on at 5 and 10 months after the first operation, had recurrence of functional tricuspid regurgitation. Visual inspection of these two tricuspid valves showed a dilated anulus with otherwise normal valves. All surviving patients are in New York Heart Association functional class I or II without significant functional tricuspid regurgitation (mean 0.78 +/- 0.56). We concluded that functional tricuspid regurgitation in patients with low pulmonary arteriolar resistance can be adequately treated by a vanishing De Vega annuloplasty, which will stent the tricuspid anulus for about 4 months.

Adolescent↗
PubMed1992

Pulmonary artery diastolic pressure: a simultaneous Doppler echocardiography and catheterization study.

Pulmonary hypertension is an important determinant of the clinical presentation of and surgical approach to patients with heart disease. To confirm the utility of continuous wave Doppler echocardiography in assessing the pulmonary artery diastolic pressure in patients with pulmonary regurgitation, 51 patients representing the wide hemodynamic spectrum of pulmonary artery pressure underwent simultaneous determination of pulmonary artery diastolic pressure by continuous wave Doppler echocardiography and cardiac catheterization. Pulmonary artery diastolic pressure was estimated from the Doppler recordings by the end-diastolic pressure gradient obtained by the modified Bernoulli equation plus the estimated right atrial pressure. A correlation was observed (r = 0.935, SEE = 7.4 mmHg) between Doppler and catheterization pulmonary artery diastolic pressure. In addition, comparison between the mean diastolic pressure gradient across the pulmonary valve by Doppler and pulmonary artery diastolic pressure at catheterization yielded a high correlation (r = 0.947, SEE = 5.1 mmHg). These data demonstrate that continuous wave Doppler echocardiography is a useful noninvasive technique for evaluating the pulmonary artery diastolic pressure in patients with pulmonary regurgitation.

Adolescent↗
PubMed1992

Percutaneous mitral valvotomy with the Inoue balloon catheter in children and adults: immediate results and early follow-up.

Percutaneous mitral balloon valvotomy (PMV) using the Inoue balloon catheter was attempted in 60 consecutive patients with severe symptomatic mitral stenosis. There were 10 children (mean age 13 years) and 50 adults (mean age 31 years). Forty patients were females and 20 were males; 53 were in sinus rhythm. The procedure was technically successfully performed in 57 (95%) patients. There were no deaths or thromboembolic complications. Balloon valvotomy was done using a 22 to 30 mm diameter catheter with the echo/Doppler guided stepwise mitral dilatation technique. After PMV the mean left atrial pressure decreased from 23.0 +/- 5.0 to 14.0 +/- 4.0 mm Hg (p less than 0.001). The mean mitral valve gradient (MVG) decreased from 15.0 +/- 4.0 to 6.0 +/- 2.0 mm Hg (p less than 0.001). The mitral valve area (Gorlin formula) increased from 0.7 +/- 0.2 to 1.6 +/- 0.4 cm2 (p less than 0.001). The mitral valve area as determined by echocardiography increased from 0.8 +/- 0.1 to 1.9 +/- 0.3 cm2 (p less than 0.001). Mild mitral regurgitation (MR) developed in six patients (11%) and increased by one grade in another five patients (9%). No patient developed severe mitral regurgitation. Mitral valve area at mean follow-up of 4.8 months remained unchanged at 1.9 +/- 0.3 cm2. We conclude that PMV, using the Inoue balloon catheter, is safe and effective in the treatment of severe mitral stenosis in children and adults, without inducing significant mitral regurgitation.

Adolescent↗
PubMed1992

Balloon coarctation angioplasty in adolescents and adults: early and intermediate results.

Twenty-three adolescent and adult patients with native coarctation of the aorta underwent balloon dilatation. Dissection of the aorta developed in one patient. Data were collected on the remaining 22 patients. They ranged in age from 15 to 55 years (mean 23 +/- 9.2 years). Invasive measurement of the peak systolic gradient (PSG) and biplane angiography were performed before and immediately after angioplasty and at follow-up 4 to 48 months (mean 15 months) later. PSG before dilatation was 37 to 100 mm Hg (mean 66.9 +/- 19.9 mm Hg) and decreased to 0 to 30 mm Hg (mean 9.1 +/- 11 mm Hg) immediately after dilatation (p less than 0.001). Restenosis occurred in two patients 6 months after dilatation, and one patient had an incomplete dilatation. These three patients underwent successful redilatation and remained improved 12 to 19 months later. There was no significant change in gradient at repeat catheterization in the remaining 20 patients. PSG was 0 to 20 mm Hg (mean 5.8 +/- 7.2 mm Hg). Angiography showed that a small aneurysm developed in one patient immediately after dilatation and in another 6 months later. Eleven patients were restudied more than once, and no change in gradient or size of the aneurysm was noted at mean follow-up 25 months after dilatation. This study demonstrated that balloon angioplasty is an effective method of treating adolescent and adult patient with native coarctation of the aorta. However, because of the uncertain natural history of aneurysm after dilatation, this procedure should be considered investigational until much longer follow-up times are available.

Adolescent↗
PubMed1992

New surgical technique for type B aortic interruption.

Restoring continuity of the aortic arch in aortic interruption continues to be a problem in terms of both surgical technique and long-term results. We report here a surgical technique using the left subclavian artery along with an aberrant right subclavian artery to form a conduit in a patient with type B interruption, to reestablish aortic continuity.

Aorta, Thoracic↗
PubMed1992

Simultaneous measurement of left atrial pressure by Doppler echocardiography and catheterization.

Simultaneous, continuous wave Doppler echocardiography, left ventricular systolic and mean pulmonary capillary wedge pressure measurements were performed during cardiac catheterization in 54 patients with mitral regurgitation. Doppler-derived left atrial pressure, which was calculated by subtracting mitral regurgitant gradient from brachial artery systolic pressure, correlated well with mean pulmonary capillary wedge pressure by catheter (r = 0.933, SEE = 2.9 mmHg, P < 0.001); a comparison between non-invasive and invasive systolic gradients across the mitral valve yielded a high correlation (r = 0.91, SEE = 6.0 mmHg, P < 0.001); and there was also a high correlation between brachial artery and left ventricular systolic pressures (r = 0.93, SEE = 4.9 mmHg, P < 0.01). It is concluded that Doppler echocardiography provides a reliable and accurate method for complete non-invasive assessment of left atrial pressure in patients with mitral regurgitation.

Adolescent↗
PubMed1992

Total cavopulmonary connection for right ventricular endomyocardial fibrosis.

Endomyocardial fibrosis is an endemic problem in tropical countries and is characterised by ventricular cavity obliteration, decreased ventricular compliance, and atrioventricular valve regurgitation. We report on a patient with right ventricular endomyocardial fibrosis resulting in obliteration of the cavity and tricuspid regurgitation treated successfully by total cavopulmonary connection and exclusion of the right ventricle.

Adult↗
PubMed1992

Right-sided endomyocardial fibrosis with recurrent pulmonary emboli leading to irreversible pulmonary hypertension.

A 26 year old Saudi man with features of both Loeffer's endocarditis and endomyocardial fibrosis presented with mild symptoms and pulmonary emboli. Echocardiographic examination showed obliteration of the right ventricular apex by an attached mass. The results of haemodynamic studies were somewhat abnormal and medical treatment was started. Despite anticoagulation with warfarin the patient's condition deteriorated rapidly over a four month period after a further episode of pulmonary embolism and the development of pulmonary hypertension. Two haemodynamic studies performed four months apart were typical of pulmonary hypertension and later right ventricular failure; they showed none of the characteristics of restriction. Pulmonary embolectomy was attempted but there was no cleavage plane between the organised thrombi and the endothelium of the pulmonary artery. The patient died of severe pulmonary hypertension and right ventricular failure several days after operation. Surgical intervention in the early stages of right-sided endomyocardial fibrosis might have prevented the development of pulmonary embolism and pulmonary hypertension.

Adult↗
PubMed1992

The vanishing tricuspid annuloplasty. A new concept.

A tricuspid De Vega annuloplasty with absorbable 2-0 polydioxanone sutures was performed on 16 sheep supported by cardiopulmonary bypass. The anulus diameter was reduced by 2 to 6 mm. Four sheep died perioperatively. The 12 survivors were electively killed at 2-week intervals during a period of 6 months. Infective endocarditis was not observed. At the time of death no gradient was found on simultaneous pressure measurements of the right atrium and ventricle. Epicardial echocardiography did not reveal tricuspid stenosis or regurgitation. Macroscopically there was no thrombus and the tricuspid leaflets were of a normal appearance. A thin white cord was observed at the anulus in all animals killed after 12 weeks. The annular size remained as surgically induced until the fourth month, but it reverted to its preoperative size after 5 months. Histologically there was granulation tissue initially only around the foreign material, but then progressively it appeared also between the foreign filaments, with the development of multinucleated foreign body giant cells. At approximately 5 months most of the foreign material had been disrupted or absorbed, leaving a tenuous ring of granulation tissue, which allowed expansion of the tricuspid ring to its original circumference. By 6 months most of the foreign material had disappeared and was replaced by loose collagenous tissue. The concept of a "vanishing annuloplasty" is advanced, with particular application in children and in patients with functional tricuspid insufficiency.

Animals↗