The double switch procedure for anatomical repair of congenitally corrected transposition of the great arteries in infants and children

AIMS: To assess outcomes of anatomical repair (double switch procedure) in infants and children with congenitally corrected transposition of the great arteries. METHODS AND RESULTS: Between September 1993 and August 1996, 17 patients with congenitally corrected transposition underwent surgery at UCSF. Anatomical repair was performed in 11 of these patients, at ages ranging from 4.8 months to 7.8 years (median 3.2 years). The remaining six patients did not undergo anatomical repair due to unfavourable anatomy (n = 2), prior conduit repair (n = 2), biventricular dysfunction (n = 1), and isolated complete atrioventricular block (n = 1). The 11 patients who underwent anatomical repair make up the study group for the present report. All 11 patients had a malalignment ventricular septal defect, while pulmonary outflow tract obstruction was present in nine patients and significant tricuspid valve pathology or dysfunction was present in five. Anatomical repair was achieved with a Senning (n = 7) or a Mustard (n = 4) procedure combined with an arterial switch operation plus ventricular septal defect closure (n = 4), or a Rastelli procedure with left ventricle to aortic baffle and right ventricle to pulmonary artery conduit (n = 7). There was one early death and no patients developed surgical complete atrioventricular block. At a median follow-up of 22 months, there were no late deaths. Two patients required a total of three late reoperations, and all patients were asymptomatic on no cardiac medication. Follow-up echocardiography revealed normal biventricular function in all patients. CONCLUSIONS: Anatomical repair of corrected transposition can be achieved with low rates of early mortality and surgical heart block, and favourable mid-term results. Long-term follow-up will be necessary to determine if the double switch approach improves the natural history of corrected transposition when compared to less aggressive surgical approaches that leave the right ventricle in the systemic circulation.     

Long-term outcome of mitral valve repair of dystrophic mitral regurgitation

Between January 1984 and December 1994, 130 patients underwent mitral valvuloplasty for pure dystrophic mitral regurgitation. There were 94 men and 36 women with a mean age of 61 +/- 9 years: 52 patients were in atrial fibrillation; 91% of patients were in NYHA Classes III or IV. At preoperative echocardiography, the regurgitation was assessed as Grade III or IV and classified using the Carpentier classification according to type I (dilatation of the annulus) or II (mitral valve prolapse); 95% of patients had isolated prolapse of the posterior leaflet, 3% had isolated prolapse of the anterior leaflet and 2% had prolapse of the two leaflets. After valvuloplasty, a prosthetic ring was implanted in 124 patients (95%). The early mortality was 3%; 5.3% of patients had early complications. All patients underwent control transthoracic echocardiography in the first postoperative week. They were reviewed with a second transthoracic echocardiography after a mean follow-up of 5 +/- 0.3 years and a cumulative follow-up of 657 years-patients. At the immediate postoperative echocardiography, 24 minimal residual regurgitations were observed; at long-term, 20 new mitral regurgitations developed, all mild without any clinical symptoms and 98% of patients were in the NYHA Classes I or II. At 10 years, the actuarial survival was 73 +/- 16%; absence of thromboembolic complications 95 +/- 3%, absence of reoperation 95 +/- 5%. This study confirms the efficacy of mitral valvuloplasty and the postoperative stability of repaired valvular lesions. These results suggest that the operative indications should be considered at an earlier stage.     

Durability of mitral valve repair for degenerative disease

BACKGROUND: Degenerative mitral valve disease is the most common cause of mitral regurgitation in the United States. Mitral valve repair is applicable in the majority of these patients and has become the procedure of choice. OBJECTIVE: This study was undertaken to identify factors influencing the durability of mitral valve repair. PATIENTS AND METHODS: Between 1985 and 1997, 1072 patients underwent primary isolated mitral valve repair for valvular regurgitation caused by degenerative disease. Repair durability was assessed by multivariable risk factor analysis of reoperation. It was supplemented by a search for valve-related risk factors for death before reoperation. Three hospital deaths occurred (0.3%); complete follow-up (4152 patient-years) was available in 1062 of 1069 hospital survivors (99.3%). RESULTS: At 10 years, freedom from reoperation was 93%. Among 30 patients who required reoperation for late mitral valve dysfunction, the repair failed in 16 (53%) as a result of progressive degenerative disease. Durability of repair was adversely affected by pathologic conditions other than posterior leaflet prolapse, use of chordal shortening, annuloplasty alone, and posterior leaflet resection without annuloplasty. Durability was greatest after quadrangular resection and annuloplasty for posterior leaflet prolapse and was enhanced by the use of intraoperative echocardiography. Death before reoperation was increased in patients having isolated anterior leaflet prolapse or valvular calcification and by use of chordal shortening or annuloplasty alone. CONCLUSIONS: Repair durability is greatest in patients with isolated posterior leaflet prolapse who have posterior leaflet resection and annuloplasty. Chordal shortening, annuloplasty alone, and leaflet resection without annuloplasty jeopardize late results.     

Partial mitral homograft: a new technique for mitral valve repair

Partial mitral homograft was used in 22 patients with localized lesions contraindicating a conventional valve repair. The etiologies of valve disease were: calcified rheumatic stenosis (n=14) and acute bacterial endocarditis (n=8). One patient died three months after surgery from cancer. Another patient required reoperation for residual stenosis 14 months postoperatively. All other patients had an excellent functional result with 19 patients in sinus rhythm. In this series, partial homograft replacement of the mitral valve significantly extended the possibilities of reconstructive surgery.     

Left ventricular false aneurysm complicating mitral valve repair

Left ventricular false aneurysm is a rare complication of mitral valve replacement or myocardial infarction. A case of left ventricular false aneurysm complicating mitral valve repair is presented. The patient was clinically asymptomatic, and the diagnosis was made on postoperative transesophageal echocardiography. The patient subsequently underwent successful mitral valve replacement and false aneurysm repair.     

The mitral valve prolapse syndrome in children and adolescents

The authors studied the prevalence of mitral valve prolapse (MVP) in the group of 656 children and adolescents (329 males and 327 females), who were a representative sample (obtained with the Monte Carlo method of statistical trials) of all newborns in the city of Maribor, Republic of Slovenia, in the period of 18 years (1976-1992). The results were considered positive in children and adolescents who in addition to possible history (chest pain, palpitations, dizziness, loss of consciousness, headaches, perspiration), probable auscultatory finding (mezzosystolic click and late systolic murmur), and suspected phonocardiographic and ECG findings, also had a positive M-mode echocardiographic finding. The criteria for MVP on M-mode echocardiography were taken from the literature: descending of mitral cusp, either anterior or posterior, of at least 3 mm below the line connecting points C and D. Children and adolescents were divided into six age groups (infants, toddlers, preschool children, early school age, children in puberty, adolescents). Assuming MVP as a cause of cardiac arrhythmias, beside standard ECG we also performed holter ECG monitoring in 61 children and adolescents (29 with MVP, 32 without MVP). The results were tested with standard statistical tools (chi 2-test, Student t-test, 2 x 2 Fisher chi 2-test). MVP was found in 71 patients (10.8%, 32 males and 39 females). As regards age and sex we found lower prevalence of MVP in male children (9.7%) compared to female children (11.9%). The highest prevalence was found in early school age, more so in females (14.2 vs 13.7). The differences were not statistically significant (p > 0.05). In both sexes most frequent was endosystolic prolapse (males 59.3%, females 51.3%). Most commonly both cusps are involved in the prolapse (males 78.1%, females 66.7%). Most frequently measured descending of the cusps was 3-4.5 mm (males 56.2%, females 48.7%). Negative auscultatory finding (silent MVP) was detected in 47.8% of the patients with MVP. Most patients with diagnosed MVP had no symptoms (71.8%). The prevalence of asymptomatic MVP declines with age in both sexes. The prevalence of arrhythmias, both in standard ECG and holter ECG, is higher in patients with MVP (6.8:0%--NS and 44.6%:9.3%--p < 0.05). The influence of constitutional changes (dolichostenomelia, asthenic constitution, genua valga) on the appearance of MVP is reflected in statistically significant difference in the Rohr' index in the group of patients with MVP in relation to the healthy group (p < 0.05). The higher prevalence of headache and dizziness in the group with MVP is statistically significant (p < 0.05).     

Artificial chordae for mitral valve reconstruction in children

BACKGROUND: Congenital mitral regurgitation continues to present a challenge for cardiac surgeons because of the diversity of the anatomy of the congenitally malformed mitral valve. We undertook aggressive repair of the mitral valve with artificial chordae for reconstruction of the prolapsed anterior leaflet in some children. The short-term results are reported herein. METHODS: Three patients with isolated congenital mitral regurgitation underwent mitral valve repair with use of expanded polytetrafluoroethylene sutures as artificial chordae. RESULTS: There have been no late deaths and no valve-related complications. Serial follow-up echocardiographic examinations have not revealed any increase in the severity of mitral regurgitation with continuing patient growth up to 39 months after the operation. CONCLUSIONS: When combined with other conservative methods of mitral valve repair, chordal replacement with expanded polytetrafluoroethylene sutures in children undergoing mitral valve reconstruction produces good short-term results. We believe that it delays and possibly prevents the need for a mechanical prosthesis with its associated complications in this young patient population.     

Late results of mitral valve repair for mitral regurgitation due to degenerative disease

From June 1981 to August 1992, 184 patients with mitral regurgitation due to degenerative disease underwent mitral valve repair. The mean age was 57 years, and 74% were men. One-third of the patients were in atrial fibrillation, and 71% were in New York Heart Association classes III and IV. The mitral regurgitation was due to prolapse of the posterior leaflet in 97 patients (53%), prolapse of the anterior leaflet in 42 (23%), and prolapse of both leaflets in 45 (24%). The degree of myxomatous changes was assessed intraoperatively as mild in 125 patients (68%), moderate in 27 (15%), and severe in 32 (17%). Mitral valve repair was accomplished largely by techniques described by Carpentier. Ring annuloplasty was performed in 160 patients (66 with Carpentier ring and 94 with Duran ring). There was one operative death, and 5 patients experienced life-threatening complications. Patients were followed up from 5 to 132 months (mean, 41 months). The actuarial survival at 8 years was 88% +/- 4%. The freedom from stroke at 8 years was 94% +/- 2%, and the freedom from transient ischemic attacks was 86% +/- 6%. Age greater than 60 years was the only factor associated with higher risk of thromboembolic complications by logistic regression analysis. The actuarial freedom from reoperation at 8 years was 95% +/- 2%. Advanced myxomatous changes in the leaflets of the mitral valve was the only significant factor associated with a higher risk of reoperation. Most patients were in New York Heart Association class I at the last follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)     

Minimally invasive mitral valve repair using transthoracic aortic occlusion

This report describes a minimally invasive mitral valve repair done through a limited (6-cm) thoracic incision. The patient was supported by peripheral extracorporeal perfusion with cardiac arrest established using a new transthoracic aortic cross-clamp and antegrade blood cardioplegia. The patient was discharged on postoperative day 3 with minimal pain. This less invasive approach to mitral valve surgery may offer combined advantages to patients by increasing comfort, expediting recovery, and decreasing surgical costs by using modified traditional methods compared with specialized intraaortic occlusive balloons.     

Surgical therapy in a case of congenital mitral valve insufficiency]

Using sheep erythrocytes (SRBC) as the antigen, two subpopulations of spleen antigen-binding lymphocytes could be distinguished by a marked difference in the susceptibility of their receptors to trypsin. In unimmunized animals, 30% of the antigen-binding cells were trypsin-resistant, whereas at 5 days after immunization, 80-90% were trypsin-resistant, indicating an increase of about 50-fold in trypsin-resistant antigen-binding cells per spleen. In contrast, trypsin-sensitive cells per spleen were only 4-fold higher on day 5 than before immunization. The rise in % trypsin sensitivity preceded the increase in rosettes per spleen, implying that immunization produced a preferential increase in trypsin-resistant antigen binding cells partly by converting sensitive cells to resistant cells. After the 5th day, the trypsin sensitivity of antigen-binding cells slowly returned toward the unimmunized level, but a booster injection of SRBC restored trypsin resistance. Trypsin resistance was not lost in the presence of sodium azide or protein synthesis inhibitors. But a slightly increased trypsin susceptibility was conferred by 2-deoxyglucose, implying that glycolysis or the glycosylation of protein may be involved in maintaining trypsin resistance.     

Aortic homograft and mitral valve repair in a patient with Werner's syndrome

We report the case of a 66-year-old man suffering from Werner's syndrome (adult progeria); he presented with several cardiac disorders, including coronary artery disease, aortic stenosis, and mitral regurgitation, mainly due to calcific deposits in the mitral annulus and the aortic cusps. Treatment consisted of mitral repair, homograft replacement of the aortic valve, and coronary artery bypass grafting. Avoidance of prosthetic material because of chronic infectious skin ulcers constituted the main goal of the operation.     

Congenital malformations of the mitral valve in children. Pathology and surgical treatment

A systematic study of congenital mitral valve malformations was undertaken on a surgical basis in an attempt to develop techniques of valvular reconstruction adapted to the various lesions. Forty-seven children between the ages of 4 months and 12 years (average 6 years, 4 months) have been operated upon between January, 1970, and March, 1976. Valvular lesions were classified into four group: Group I, mitral insufficiency owing to valvular lesions: Group II mitral insufficiency with subvalvular lesions; Group III, mitral insufficiency and stenosis; Group IV, stenosis. Associated lesions (ventricular or atrial septal defects, coarctation, or aortic valve stenosis) were present in 31 patients (65 per cent) and were corrected during the same operation. Valve reconsruction was possible in 38 patients whereas valve replacement was necessary in 9 patients. In the valve repair group there were three operative deaths (8 per cent), no late deaths, one reoperation for residual ventricular septal defect, and one myocardial infarction. In the valve replacement group of 9 patients, there were three operative deaths, three late deaths, and one case of repeated embolization. Thirty-one of 38 patients in the valve repair group were classified into Functional Class I after the operation (86 per cent), 2 were in Class II, and one in Class III. Minimal or moderate regurgitation and cardiomegaly persisted in the majority of the patients. Pulmonary artery pressure significantly decreased, however, as demonstrated by postoperative catheterization in 17 patients.     

Successful surgical repair of left atrial dissection after mitral valve replacement

A rare case of left atrial dissection after mitral valve replacement is reported. Low output syndrome developed in the immediate postoperative period. Cardiac catheterization showed marked elevation of the pulmonary wedge pressure, and left ventriculography revealed massive paraprosthetic leakage with left atrial dissection. At the reoperation, the dissecting cavity was successfully closed from inside the left atrium under cardiopulmonary bypass. We consider this complication another variation of an atrioventricular discontinuity after mitral valve replacement.     

Damage to the circumflex coronary artery during mitral valve repair with sliding leaflet technique

We report a case of damage to the circumflex coronary artery during mitral valve repair using sliding leaflet technique in a patient with a posterior mitral leaflet prolapse and coronary artery disease who underwent mitral valve reconstruction using Carpentier's technique and coronary artery bypass grafting. This case underscores the risk of circumflex coronary artery injury during mitral valve reconstruction, especially in patients with left coronary dominance or codominance, and therefore emphasizes the importance of knowing the coronary artery anatomy preoperatively. The use of intraoperative transesophageal echocardiography is mandatory for the evaluation of mitral valvuloplasty.