Comparative long-term results of surgery versus balloon valvuloplasty for pulmonary valve stenosis in infants and children

BACKGROUND: We compared the long-term results of surgical valvotomy (S) versus balloon valvuloplasty (BV) for pulmonary valve stenosis in infants and children. METHODS: Results after surgical pulmonary valvotomy (with concomitant ASD/VSD closure) (n = 62, age 2.9 +/- 3.5 years) and balloon valvuloplasty (n = 108, age 3.6 +/- 3.9 years) were analyzed. Transvalvular mean pressure gradient decrease, freedom from reintervention for restenosis, pulmonary valve insufficiency, and tricuspid valve insufficiency were considered. RESULTS: Mean pressure gradient decreased significantly more in the surgical group (from 64.8 +/- 30.8 mm Hg to 12.8 +/- 9.8 mm Hg at a mean follow-up of 9.8 years) than after BV (decreasing from 66.2 +/- 21.4 mm Hg to 21.5 +/- 15.9 mm Hg after a mean of 5.4 years; p < 0.001). Moderate pulmonary valve insufficiency occurred in 44% after surgery, and in 11% after BV (p < 0.001). Tricuspid valve insufficiency occurred in 2% after surgery, and in 5% after BV. Restenosis occurred in 3 surgical patients (5.6%), 2 patients required reoperation, and 1 patient required a balloon valvotomy. Restenosis developed in 13 BV patients (14.1%): 6 patients were redilated and 7 patients required surgery. Surgical valvotomy led to significantly less reinterventions than balloon valvuloplasty (p < 0.04). CONCLUSIONS: Surgical relief of pulmonary valve stenosis produces lower long-term gradients and results in longer freedom from reintervention. Balloon valvuloplasty may remain, despite these results, the preferred therapy for isolated pulmonary valve stenosis, because it is less invasive, less expensive, and requires a shorter hospital stay. Surgery should remain the exclusive form of therapy in the presence of concomitant intracardiac defects, which need to be addressed.     

Balloon valvuloplasty after pulmonary valvotomy for babies with pulmonary atresia and intact ventricular septum.

During a 2 1/2-year period, staged procedures of transventricular closed pulmonary valvotomy followed by balloon valvuloplasty were attempted in 12 babies with pulmonary atresia and an intact ventricular septum. All babies immediately underwent valvotomy when echocardiography revealed a tripartite right ventricle with adequate inflow and outflow dimensions and without sinusoidal-coronary arterial fistulas. After valvotomy, the overall mortality rate was 25% (3/12), but the only surgical death (1/12, 8%) was due to failure to establish continuity between the right ventricular cavity and the pulmonary trunk. The other 2 babies died of neonatal complications after successful valvotomy. Angiocardiography performed 5 to 18 months after valvotomy documented substantial growth of the right ventricular inflow and outflow dimensions in the 9 survivors. Twelve balloon dilation procedures were then performed in 7 babies. All except 1 achieved a significant drop in the right ventricular to left ventricular peak systolic pressure ratio (0.96 +/- 0.40 to 0.56 +/- 0.28; p less than 0.01). Balloon valvuloplasty was not required in 1 baby and failed in the other, who then underwent successful right ventricular outflow tract reconstruction. After these staged procedures, follow-up at 1 month to 20 months (mean follow-up, 14.8 months) revealed resting cyanosis in 3 babies, which was related to severe residual infundibular stenosis (55 mm Hg) in 1 and a subnormal tricuspid valve annulus in 2. The remaining 5 babies (including 1 who required no valvuloplasty) were active and pink (saturation greater than 97%) and had a mean Doppler estimated gradient of 19 mm Hg (range, 8 to 36 mm Hg) across the pulmonary valve.(ABSTRACT TRUNCATED AT 250 WORDS)     

Right ventricular growth potential in neonates with pulmonary atresia and intact ventricular septum

The cardiac catheterization data and angiograms of 30 infants with pulmonary atresia and intact ventricular septum were reviewed to evaluate the growth potential of the right ventricle after transventricular pulmonary valvotomy. An index of right ventricular size based upon the tricuspid valve anulus, right ventricular inlet, and right ventricular outlet dimensions was used. Fourteen infants (Group I) were treated with systemic-pulmonary arterial shunts only, whereas 16 infants (Group II) underwent pulmonary valvotomy and 14 had shunting as well. Follow-up studies demonstrated the lack of right ventricular growth in Group I (right ventricular index of 7.0 +/- 3.2 preoperatively versus 7.0 +/- 2.0 postoperatively) and persistence of severe right ventricular hypertension (systolic pressure of 121 +/- 31 versus 120 +/- 48 mm Hg). In contrast, the right ventricular cavity increased in nine of 11 Group II infants who underwent valvotomy. Right ventricular index increased from 7.7 +/- 1.6 to 11.0 +/- 3.1 (p less than 0.01) and systolic pressure fell from 132 +/- 31 to 83 +/- 50 mm Hg (p less than 0.1). Early and late mortality in Group I was 50% (7/14), whereas only three of 16 Group II infants died (p greater than 0.1). It is concluded that pulmonary valvotomy should be attempted in all neonates with pulmonary atresia and intact ventricular septum in whom an outflow tract is identified angiographically to maximize the potential for right ventricular growth and increase its functional contribution to normal circulation.     

Improved right ventricular function following late pulmonary valve replacement for residual pulmonary insufficiency or stenosis

Residual severe pulmonary insufficiency or stenosis may result in significant myocardial dysfunction late after repair of tetralogy of Fallot. Although pulmonary valve replacement has been advocated for selected patients, objective improvement in right ventricular function has been difficult to demonstrate. We undertook pulmonary valve replacement in 11 patients to treat residual insufficiency (n = 8) or stenosis (n = 3) and evaluated them before and after operation by radionuclide ventriculography and M-mode echocardiography. Patients' age at the original repair was 6.6 +/- 0.6 years (range 2 to 8 years) and at subsequent valve replacement was 14.6 +/- 1.5 years (range 5 to 20 years). Indications for pulmonary valve replacement were conduit stenosis indicated by a gradient greater than or equal to 75 mm Hg (n = 3), symptoms (n = 2), progressive cardiomegaly (n = 3), and new onset of tricuspid insufficiency (n = 3). Prior to pulmonary valve replacement, right ventricular ejection fraction was 0.29 +/- 0.12 (range 0.12 to 0.48) and rose to 0.35 +/- 0.10 (range 0.19 to 0.48) at a mean of 10.5 +/- 2.3 months after operation (p less than 0.05). Improvement (defined as an increase in ejection fraction greater than 0.05) was noted in seven patients whereas four demonstrated no change. Left ventricular ejection fraction before operation (0.55 +/- 0.12) was unchanged after pulmonary valve replacement (0.54 +/- 0.06). M-mode echocardiography demonstrated significant reduction in right ventricular dilatation. Right ventricular/left ventricular end-diastolic dimension fell from 1.03 +/- 0.30 to 0.73 +/- 0.13 after operation (p less than 0.01). Cardiothoracic ratio fell from 0.59 +/- 0.02 to 0.55 +/- 0.02 at a mean of 12 months after pulmonary valve replacement (p less than 0.01). Subjective improvement in exercise tolerance was noted in all seven patients who showed an increase in right ventricular ejection fraction. Of the remaining four patients, two had no improvement, one felt symptomatically improved, and one was too young for evaluation. These data demonstrate objective improvement in right ventricular function following pulmonary valve replacement and confirm the usefulness of this procedure in patients with significant right ventricular dysfunction secondary to residual pulmonary insufficiency and stenosis.     

Staged biventricular repair of pulmonary atresia or stenosis with intact ventricular septum

BACKGROUND: Since 1991 we have performed a multistage palliative approach to biventricular repair of pulmonary atresia or critical pulmonary stenosis with intact ventricular septum in infants with a detectable right ventricular infundibulum. METHODS: A total of 25 patients (19 pulmonary atresia and 6 critical pulmonary stenosis) underwent initial palliation consisting of a transarterial pulmonary valvotomy and a polytetrafluoroethylene shunt between the left subclavian artery and pulmonary trunk. Among the 23 survivors, 15 underwent balloon valvotomy. Six of these patients later required additional palliative surgery that consisted of repeat pulmonary valvotomy, adjustment of an atrial communication, and resection of the hypertrophied muscles in the right ventricle. RESULTS: Of the 25 patients, 23 (92%) survived. In all, 20 patients underwent definitive operations: 18 (90%) biventricular repair (12 pulmonary atresia, and 6 critical pulmonary stenosis), one bidirectional Glenn, and one Fontan procedure. The actuarial probability of achieving a biventricular repair at 36 months of age was 69%. In 18 patients right ventricular end-diastolic volume significantly increased but tricuspid valve diameter did not change. CONCLUSIONS: The multistage palliation procedure to promote right ventricular growth makes a definitive biventricular repair of pulmonary atresia or critical pulmonary stenosis with intact ventricular septum possible in the majority of infants with a patent infundibulum.     

Right ventricular function in patients with aortic stenosis undergoing aortic valve replacement.

The effects of aortic stenosis (AS) on right ventricular function during cardiac surgery are not fully understood. Forty patients undergoing aortic valve replacement with either a systolic transvalvular gradient of less than 100 mm Hg (82.1 +/- 5.5 mm Hg; group 1, n = 20) or greater than 120 mm Hg (131.1 +/- 6.9 mm Hg, group 2, n = 20) were investigated with regard to right ventricular function in the perioperative period. Right ventricular ejection fraction (RVEF), right ventricular end-systolic volume (RVESV), and right ventricular end-diastolic volume (RVEDV) were measured by means of the thermodilution technique. Before cardiopulmonary bypass (CPB), RVEF was significantly lower in group 2 patients (34% +/- 6%) than in group 1 (45% +/- 5%). After CPB, RVEF increased significantly in group 2 (28% +/- 4% to 49% +/- 5%), and no further differences were noted between the groups. In the patients with a higher systolic transvalvular gradient, RVEDV and RVESV were lower at the start of surgery, but increased after opening the pericardium. Cardiac index was also lower in these patients. Pericardiotomy resulted in a decrease in right ventricular end-systolic pressure (RVESP) only in the patients of group 2. In these patients more epinephrine was necessary to maintain stable hemodynamics during the post-bypass period. It is concluded that patients with AS are at risk of reduced right ventricular function when the systolic transvalvular pressure gradient is more than 120 mmHg. Knowledge of the complex interaction between the two sides of the heart may enable anesthesiologists to optimize management during the perioperative period.     

Surgical intervention in neonates with critical pulmonary stenosis.

The surgical experience with 18 consecutive neonates with critical pulmonary stenosis (PS) and intact ventricular septum was reviewed. All patients had cardiac catheterization with calculation of right ventricular volume. Group A patients (N = 8) had a small right ventricular end-diastolic volume (RVEDV less than 72% of predicted). Group B patients (N = 10) had a normal or enlarged RVEDV. All patients had a closed pulmonary valvotomy. Five Group A patients required a systemic-pulmonary shunt or prostaglandin (PGE1) after operation; one patient died. Nine Group B patients did well after valvotomy; one moribund patient died after valvotomy and shunt. Six of 16 survivors required reoperation: valvectomy in four patients and shunt takedown in two patients. Four of the six patients who had reoperation also had a transannular patch. There was one unrelated late death. All long-term survivors are asymptomatic. Recatheterization in four patients with a small right ventricle (RV) documented significant RV growth. In conclusion, most neonates with critical PS can be managed with closed valvotomy. Patients with a small RV may require PGE1 or a shunt after operation for persistent hypoxemia. Some patients with a small RV will have significant RV growth after valvotomy.     

Prevalence and risk factors of tricuspid regurgitation after correction of tetralogy of Fallot

Tricuspid regurgitation was evaluated in 133 patients with tetralogy of Fallot after corrective operations for a real-time Doppler flow imaging system. Moderate or severe tricuspid regurgitation was found in 15% (10/66) of patients in whom the ventricular septal defect was closed through the right atrium and tricuspid valve, 13% (2/15) through the pulmonary artery, and 25% (13/52) through the right ventricle. These differences were not significant. Right ventricular systolic pressure was significantly higher (66 +/- 27 mm Hg) in patients with moderate or severe tricuspid regurgitation (group A) than in patients with mild or no tricuspid regurgitation (group B) (41 +/- 13 mm Hg) (p less than 0.01). Right ventricular end-diastolic pressure was significantly higher in group A (7.7 +/- 2.2 mm Hg) than in group B (6.1 +/- 2.9 mm Hg) (p less than 0.01). Significant pulmonary regurgitation (angiographic grades 3/4 to 4/4) was more frequent in group A (8/18; 44%) than in group B (14/64; 22%) (p less than 0.05). Residual ventricular septal defect (pulmonary/systemic flow ratio greater than 1.3) was also more frequent in group A (5/18; 28%) than in group B (0/64; 0%) (p less than 0.01). Right ventricular end-diastolic volume was significantly higher in group A (202% +/- 79% of the normal right ventricle) than in group B (158% +/- 38% of normal) (p less than 0.01). Thus significant tricuspid regurgitation was associated with high right ventricular systolic pressure, high right ventricular end-diastolic pressure, and significant pulmonary regurgitation and residual ventricular septal defect, which increased the right ventricular end-diastolic volume. Operative procedure for closing the ventricular septal defect was not related to the development of significant tricuspid regurgitation.     

Pulmonary vascular dynamics after percutaneous mitral valvotomy

Hemodynamic studies were performed immediately before, within 1/2 hour, and every 8 hours for 24 hours after percutaneous mitral valvotomy in 22 patients with severe mitral stenosis and pulmonary hypertension. The mean pressure in the left atrium decreased from 27 +/- 2 mm Hg to 14 +/- 1 mm Hg (p less than 0.01) immediately after successful valvotomy. There was no significant further drop in left atrial pressure (or pulmonary capillary wedge pressure) over 24 hours. Mean cardiac output increased from 3.9 +/- 0.3 L/min to 4.6 +/- 0.3 L/min immediately after successful valvotomy (p less than 0.01). Cardiac output continued to rise for the next 8 hours and plateaued during the 24-hour period of observation. Pulmonary vascular resistance dropped immediately after the relief of mitral valve obstruction in all patients. In the group of patients who had elevated pulmonary vascular resistance after valvotomy, resistance continued to drop significantly (p less than 0.05) over the next 24 hours. In some cases it did not fall to normal levels despite adequate relief of mitral stenosis.     

Acute control of pulmonary regurgitation with a balloon "valve". An experimental investigation

Operations for certain congenital cardiac lesions can produce pulmonary regurgitation. Pulmonary regurgitation contributes to right ventricular dysfunction, which may cause early postoperative morbidity and mortality. To ameliorate the problems of pulmonary regurgitation during the early postoperative period, we evaluated a method for its acute control. Complete pulmonary valvectomy was performed utilizing inflow occlusion in eight sheep. A catheter with a 15 ml spherical balloon was positioned in the pulmonary arterial trunk; its inflation and deflation were regulated by an intra-aortic balloon pump unit. Blood flow from the pulmonary arterial trunk and forward and regurgitant fraction were determined from electromagnetic flow transducer recordings. The regurgitant fraction with uncontrolled pulmonary regurgitation was 38% +/- 3% (forward flow = 42 +/- 5 ml/beat and regurgitant flow = 16 +/- 2 ml/beat). Inflation of the balloon during diastole was timed to completely eliminate pulmonary regurgitation. This balloon control of pulmonary regurgitation increased pulmonary arterial diastolic pressure from 12 +/- 1 to 17 +/- 1 mm Hg (p less than 0.0001) and decreased pulmonary arterial systolic pressure from 31 +/- 3 to 27 +/- 1 mm Hg (p = 0.06). Pulmonary arterial pulse pressure decreased from 19 +/- 3 to 9 +/- 1 mm Hg (p less than 0.003). Elimination of pulmonary regurgitation decreased right ventricular stroke volume (25 +/- 3 versus 42 +/- 5 ml/beat, p less than 0.0002) and resulted in a 46% reduction in right ventricular stroke work (5.0 +/- 0.6 versus 9.4 +/- 1.0 gm-m/beat, p less than 0.001) with no change in net forward pulmonary artery flow. Thus, acute pulmonary regurgitation can be controlled and this control improves overall hemodynamic status and decreases right ventricular work.     

Experience with one and a half ventricle repair

OBJECTIVE: This article presents a 10-year experience with one and a half ventricle repair for right ventricular hypoplasia or dysfunction. METHODS: From November 1986 to December 1996, 30 patients (mean age 6.7 +/- 8.5 years, range 4 months-40 years) with functionally abnormal right ventricles underwent a bidirectional Glenn shunt as part of the repair. Diagnoses included pulmonary atresia with intact ventricular septum (n = 15), Ebstein anomaly (n = 5), levotransposition of the great arteries (n = 3), pulmonary stenosis with right ventricular hypoplasia (n = 2), tetralogy of Fallot (n = 3), dextrotransposition of the great arteries (n = l), and Uhl anomaly (n = l). Concomitantly performed cardiac procedures included atrial septal defect closure (n = 27), fenestration of the atrial septum (n = 2), right ventricular cavity augmentation (n = 8), right ventricular outflow tract enlargement (n = 6), transannular patch (n = 13), modified Blalock-Taussig shunt closure (n = 16), tricuspid replacement (n = 3), tricuspid repair (n = 2), Rastelli procedure (n = 3), tricuspid commissurotomy (n = 2), and double switch (n = l). RESULTS: There were 2 early deaths (6.6%) and 1 late death. Mean early postoperative superior vena caval pressure was 14. 12 +/- 3.55 mm Hg and mean right atrial pressure was 10.3 +/- 5.16 mm Hg. Early oxygen saturation in the operating room with an inspired oxygen fraction of 1 was 97.2 +/- 2.5; oxygen saturation was 92.3 +/- 4.8 on room air at discharge. Mean oxygen saturations were 93.6% +/- 3.6% at 1 year of follow-up (P =.10) and 93.5% +/- 4. 1% at 5 years (P =.12). Overall survival was 90% at 5 years, and 21 patients (77%) were in New York Heart Association class I, 5 (18%) were in class II, and 1 (2.7%) was in class III. CONCLUSION: This procedure provides a valid alternative for correction of right ventricle hypoplasia or dysfunction. Early and intermediate follow-up results compare favorably with those of the Fontan procedure, but long-term follow-up is needed.     

Relationship of right and left ventricular negative diastolic pressures, hypercontractility, and relief of outflow tract obstructions

Continuous postoperative right and left ventricular diastolic pressures were measured in 12 consecutive patients undergoing pulmonic valvotomy and in 13 consecutive patients undergoing membranectomy and myectomy for discrete subaortic stenosis. All 25 patients had positive preoperative diastolic ventricular pressures. Negative ventricular diastolic pressure was detected immediately postoperatively in all 25. The lowest left ventricular negative diastolic pressure was -38 mm Hg, and the lowest right ventricular negative diastolic pressure was -28 mm Hg. Intravenous administration of volume (blood) reduced the right ventricular negative diastolic pressure significantly (from -14.8 +/- 9.2 to -6.4 +/- 6.8 mm Hg, p less than 0.001) and decreased right ventricular rate of pressure rise from 1100 +/- 320 to 380 +/- 180. Left ventricular negative diastolic pressure was not significantly affected (from -17 +/- 11 to -14.7 +/- 11 mm Hg). Left ventricular negative diastolic pressure disappeared spontaneously 6 to 9 hours postoperatively in association with a spontaneous decrease of left ventricular rate of pressure rise (from 3450 +/- 610 to 2100 +/- 660 mm Hg/sec). We conclude that negative right and left ventricular pressures are common findings immediately after surgical relief of outflow obstructions. Hypercontractility is the main reason for these phenomena. Volume load reduces the right ventricular negative diastolic pressure, but has insignificant effect on left ventricular negative diastolic pressure. The pathogenesis of the hypercontractility is discussed.     

Circulatory support for right ventricular dysfunction

New modes of circulatory support for right ventricular dysfunction have recently been described. The present study compared the effectiveness of pulmonary artery balloon counterpulsation with a right ventricular assist device for support of surgically induced right ventricular dysfunction. Right ventricular hypertrophy was created in 16 neonatal lambs by pulmonary artery banding. Right ventricular dysfunction was produced in all animals by performing a right ventriculotomy and maintaining the pulmonary artery band. Four unassisted animals developed severe acute right heart failure and died. Six sheep had pulmonary artery balloon counterpulsation with a Dacron graft anastomosed to the proximal pulmonary artery as a reservoir for a 40 ml intra-aortic balloon after the onset of heart failure. The remaining six sheep had a pneumatically activated ventricular assist device inserted between the proximal pulmonary artery and the right ventricular apex. Periods of circulatory support with the balloon pump and the assist device on and off were compared. Decreases in right atrial pressure were observed with both balloon counterpulsation and right ventricular assistance: 14 +/- 1 to 11 +/- 1 mm Hg, p less than 0.0001, versus 19 +/- 2 to 12 +/- 2 mm Hg, p less than 0.0002, respectively. Cardiac output increased with both balloon counterpulsation and ventricular assistance: 1.45 +/- 0.16 to 2.03 +/- 0.13 L/min, p less than 0.001, versus 0.72 +/- 0.15 to 2.24 +/- 0.23 L/min, p less than 0.0002, respectively. Aortic systolic pressure increased in both support groups: 78 +/- 7 to 99 +/- 6 mm Hg, p less than 0.0004, versus 53 +/- 9 to 85 +/- 9 mm Hg, p less than 0.0001, respectively. Ventricular assistance produced greater changes in the right atrial pressure (39% +/- 6% versus 17% +/- 3%, p less than 0.01), cardiac output (153% +/- 39% versus 54% +/- 11%, p less than 0.05), and aortic systolic pressure (85% +/- 13% versus 39% +/- 9%, p less than 0.01). The insertion of a right ventricular assist device caused a significant increment in right ventricular dysfunction. These data, obtained with the devices in place but not operating, showed significantly increased right atrial and right ventricular end-diastolic pressures and approximately 50% less cardiac output than with the pulmonary artery balloon counterpulsation system. The results demonstrate that both modes of circulatory support were effective in reversing surgically induced right ventricular failure.(ABSTRACT TRUNCATED AT 400 WORDS)     

Prognostic factors in valvotomy for critical aortic stenosis in infancy

Aortic valvotomy for critical aortic stenosis in infancy has had a high mortality. To determine the factors that influence survival, we reviewed the cases of 24 infants who underwent aortic valvotomy in the first 6 months of life (mean 4 1/2 weeks) for aortic stenosis from 1978 to 1984. Cardiopulmonary bypass was used in all patients. Operative mortality was 21% (5/24), four of the five deaths occurring from low cardiac output. Analysis of preoperative factors affecting survival versus nonsurvival revealed that low ejection fraction (60% +/- 17% in survivors versus 36% +/- 2% in nonsurvivors), high left ventricular end-diastolic pressure (16 +/- 7 mm Hg in survivors versus 30 +/- 14 mm Hg in nonsurvivors), and presence of endocardial fibroelastosis (25% in survivors versus 100% in nonsurvivors) all were predictive of a poor outcome, although the small sample size indicated caution in interpreting results. Factors that did not appear to influence survival included peak systolic gradient (79 +/- 30 mm Hg in survivors versus 60 +/- 15 mm Hg in nonsurvivors) and left ventricular end-diastolic volume (37 +/- 17 cm3/m2 in survivors versus 36 +/- 7 cm3/m2 in nonsurvivors). Four patients with a left ventricular end-diastolic volume below 26 cm3/m2 survived. Postoperative gradients averaged 25 +/- 21 mm Hg at 3.4 +/- 2 years' follow-up in nine recatheterized patients. Ejection fraction of these patients increased from 45% +/- 10% to 70% +/- 11% and left ventricular end-diastolic volume increased from 37 +/- 17 to 58 +/- 5 cm3/m2. Two of 17 patients have required apical-aortic conduits; all other patients are asymptomatic. We conclude that infants with critical aortic stenosis benefit from valvotomy even with impaired left ventricular function and severely reduced left ventricular dimensions and many have nearly normal hemodynamics on late follow-up.     

Intrauterine creation and repair of pulmonary artery stenosis in the fetal lamb. Weight and ultrastructural changes of the ventricles

Fetal lamb experimental models were employed for intrauterine creation and repair of pulmonary artery stenosis. The study group was composed of 51 fetal lambs including 29 models of pulmonary artery stenosis and 22 control lambs. Gestational age was 89 days at creation of pulmonary artery stenosis. Fourteen fetal lambs (Group A) were studied after creation of the stenosis at 131 days of gestation and compared to normal age-matched control lambs. The systolic right ventricular pressure was significantly higher after creation of pulmonary artery stenosis (76.6 +/- 17.8 versus 50.3 +/- 23.5 mm Hg), but the systolic pulmonary artery pressure was unchanged. The mean right ventricular weight and the mean right ventricular/left ventricular weight ratio were significantly greater after pulmonary artery stenosis than in normal control animals. The transverse myocyte diameter was not modified by pulmonary artery stenosis, but on electron microscopic study the myocytes appeared mature. Ten lambs (Group B) underwent intrauterine repair of pulmonary artery stenosis at 131 days of gestation without cardiopulmonary bypass. The pulmonary artery was clamped and patched. Immediately after repair the right ventricular pressure fell significantly from 85.8 +/- 18.9 to 62.2 +/- 14.6 mm Hg. At birth, 7 +/- 6 days after repair, Group B was compared to Group C (unrepaired pulmonary artery stenosis, five fetuses) and to normal control lambs. The mean right ventricular weight and the mean right ventricular/left ventricular weight ratio were not statistically different in Group B and in the control group. There were no ultrastructural changes after intrauterine repair. We conclude that intrauterine creation of pulmonary artery stenosis causes right ventricular hypertrophy with more mature myocytes. Intrauterine repair of pulmonary artery stenosis is feasible without cardiopulmonary bypass and rapidly abolishes the preponderance of right ventricular weight over left ventricular weight.     

Pulmonary hypertension in isolated aortic stenosis. Hemodynamic correlations and follow-up

The clinical, hemodynamic, and angiographic data on 92 patients with severe isolated aortic stenosis were reviewed to determine the incidence and mechanism of pulmonary hypertension. The status of each of these patients was determined 1 to 8 years after diagnosis by cardiac catheterization. Patients were divided into three groups on the basis of the pulmonary artery systolic pressure: group 1 (less than or equal to 30 mm Hg), 46 patients; Group 2 (31 to 50 mm Hg), 31 patients; and Group 3 (greater than 50 mm Hg), 15 patients. The prevalence of pulmonary hypertension was 50% (46/92) and that of severe pulmonary hypertension, 16% (15/92). There was no significant difference in age, aortic valve gradient, or valve area among the three groups. There was a significant positive correlation in left ventricular end-diastolic pressure (group 1, 15.5 +/- 7.2 mm Hg; group 2, 23.3 +/- 8.1 mm Hg; and group 3, 29.5 +/- 5.8 mm Hg; R = 0.56, p less than 0.01). There was also a significant negative correlation in left ventricular ejection fraction (group 1, 67.5% +/- 14%; group 2, 62.3% +/- 13.8%; and group 3 49.9% +/- 18.3%; R = 0.43, p less than 0.01). Of the 92 patients, 85 had aortic valve replacement with four (4.7%) hospital deaths. Follow-up showed excellent symptomatic relief in all three groups. Thirteen of the 15 patients in group 3, with severe pulmonary hypertension, had aortic valve replacement. There were no hospital deaths and only one noncardiac death at follow-up in Group 3 patients, and 11 of the 12 surviving patients were in New York Heart Association functional class I. We conclude that pulmonary hypertension is common in isolated aortic stenosis and is related to an elevated left ventricular end-diastolic pressure, frequently with preserved systolic function. Surgical results are excellent.     

Surgical management of critical pulmonary stenosis in the neonate

Experience with 36 consecutive neonates less than 1 month of age with critical pulmonary stenosis (PS) with intact ventricular septum was analyzed to define the role of pulmonary valvotomy and of a concomitant systemic-pulmonary shunt as well as the impact of prostaglandin E1 (PGE1) therapy in the management of this disorder. Operative procedures included pulmonary valvotomy as an isolated procedure (Group 1, N = 22), pulmonary valvotomy plus a systemic-pulmonary shunt (Group 2, N = 8), pulmonary valvotomy with PGE1 therapy (Group 3, N = 5), and one miscellaneous procedure. The hospital mortality (+/- 70% confidence limits [CL]) by treatment group was as follows: Group 1, 54% (CL, 41-67%) (12/22); Group 2, 25% (CL, 9-50%) (2/8); and Group 3, 0 (CL, 0-32%); Group 1 versus Group 2 plus Group 3 (p less than or equal to 0.05). Patients managed with a shunt or perioperative administration of PGE1 experienced a significant improvement in early survival. Late postoperative angiography demonstrated exemplary right ventricular growth in the majority of patients, although important residual abnormalities of the outflow tract necessitating operative repair were frequently present (5-year and 10-year actuarial freedom from reoperation, 73 +/- 10% and 42 +/- 16%, respectively [+/- standard error of the mean]). This review illustrates the limitations of pulmonary valvotomy as an isolated therapeutic method in neonates with critical PS. Provision of a systemic extracardiac source of pulmonary blood flow, accomplished by a systemic-pulmonary shunt or PGE1 infusion continued postoperatively, is the most important determinant of early survival in this disorder.     

分期全腔静脉-肺动脉连接术治疗复杂先天性心脏病

目的 总结分期全腔静脉.肺动脉连接术(TCPC)治疗复杂先天性心脏病的经验.方法 1998年6月至2008年3月,22例先天性心脏病复杂畸形患者接受分期TCPC.本组中单心室合并肺动脉狄窄9例,合并肺动脉闭锁3例;完全性大动脉转位,十字交叉心,肺动脉瓣狭窄1例;完全性房室通道,左心窒发育不良,肺动脉闭锁,房室瓣少-中量反流1例;完全性房室通道,动脉导管未闭,肺动脉狭窄,双向Glenn术后伴吻合口狭窄房室瓣大量反流1例;镜面右位心,功能性单心室,肺动脉闭锁,动脉导管未闭,体肺侧支,双侧双向Glenn术后2年,右下肺动-静脉瘘1例;三尖瓣闭锁并肺动脉狭窄4例;三尖瓣闭锁伴肺动脉闭锁,动脉导管未闭1例;镜面右位心,右心室双出口,窒间隔缺损,左心室发育小良,功能性单心房,肺动脉瓣狭窄,三尖瓣少量反流,粗大体肺侧支1例.第一期体肺分流术后,二期双向Glenn术5例,第一期单侧或双侧双向Glenn手术17例.行双向Glenn手术的年龄为(5.9±4.4)岁,Glenn术前肺动脉压为17～20 mm Hg(1 mm Hg=0.133 kPa);房室瓣膜关闭不全3例;一期手术前Nakata指数小于200 mm2/m2者4例.接受TCPC术平均年龄为(9.6±4.9)岁,与双向Glenn术间隔时间(3.7 ±1.2)年,术前经上腔静脉置管测得肺动脉压力均小于15 mm Hg.全组22例均采用心外管道TCPC,房窜瓣成形1例.结果 全组住院死亡1例,病死率为4.5%.死亡病例为单心室,肺动脉闭锁,第一期体肺分流术后,二期左肺动脉成形双向Glenn术后5年第三期行TCPC,术后左肺反复多次大出血死亡.余患者均顺利出院,术后中心静脉压12～18 mm Hg.出院前经皮测血氧饱和度为90%～96%,活动量明显增加,发绀及气促症状消失,心功能均为NYHA分级Ⅰ～Ⅱ级.结论 对于高危患者根据病情选择分期TCPC,可以使更多有高危因素不能行Fontan手术的患者得到救治的机会,扩大手术适应证,并取得满意疗效.     

Factors affecting late survival after surgical remodeling of left ventricular aneurysms

OBJECTIVES: Surgical remodeling of the left ventricle has involved various techniques of volume reduction. This study evaluates factors that influence long-term survival results with 3 operative methods. METHODS: From 1979 to 2000, 157 patients (134 men, mean age 61 years) underwent operations for class III or IV congestive heart failure, angina, ventricular tachyarrhythmia, and sudden death after anteroseptal myocardial infarction. The preoperative ejection fraction was 28% +/- 0.9% (mean +/- standard error), and the pulmonary artery occlusive pressure was 15 +/- 0.07 mm Hg. Cardiogenic shock was present in 26 patients (16%), and an intra-aortic balloon pump was used in 48 patients (30%). The type of procedure depended on the extent of endocardial disease and was aimed at maintaining the ellipsoid shape of the left ventricle cavity. In group I patients (n = 65), radical aneurysm resection and linear closure were performed. In group II patients (n = 70), septal dyskinesis was reinforced with a patch (septoplasty). In group III patients (n = 22), ventriculotomy closure was performed with an intracavitary oval patch. RESULTS: Hospital mortality was 16% (25/157) and was similar among the groups. Actuarial survival up to 18 years was better with a preoperative ejection fraction of 26% or greater (P =.004) and a pulmonary artery occlusive pressure of 17 mm Hg or less (P =.05). Survival was worse in patients who had intra-aortic balloon pump support (P =.03). Five-year survival for all patients in group III was higher than for patients in group II (67% vs 47%, P =.04). CONCLUSIONS: Factors that improved long-term survival after left ventricular surgical remodeling were intraventricular patch repair, preoperative ejection fraction of 26% or greater, and pulmonary artery occlusive pressure of 17 mm Hg or less without the need for balloon pump assist.     

Left heart hypoplasia and neonatal aortic arch obstruction: is the Rhodes left ventricular adequacy score applicable?

OBJECTIVE: Although the influence of small left heart structures on outcome of a biventricular repair in neonatal critical aortic stenosis is well documented, little is known about its effect in neonates with aortic arch obstruction and coarctation. The purpose of this study was to evaluate the influence of small left heart structures on early and late results of repair and the ability to achieve a biventricular repair in neonates with coarctation and aortic arch obstruction. PATIENTS: Neonates included in this study had a left ventricular adequacy score (as proposed by Rhodes and associates for critical aortic stenosis) that would have predicted a need for a univentricular (Norwood) repair. All were ductus dependent but had antegrade ascending aortic flow and a small but nonstenotic aortic valve (<30 mm Hg gradient). Twenty neonates aged 10 +/- 9 days were identified for the study with weights averaging 3. 1 +/- 0.6 kg. Selected left heart measurements obtained by preoperative echocardiography included the following: aortic anulus 5.3 +/- 0.3 mm, mitral anulus 8.4 +/- 1.0 mm, transverse aortic arch 3.4 +/- 0.6 mm, and left ventricular volume 25 +/- 4 mL/m2. All patients underwent coarctation repair by resection and extended end-to-end anastomosis to enlarge the transverse arch as needed. Three patients underwent simultaneous pulmonary artery banding because of a hemodynamically significant ventricular septal defect. These 3 patients have subsequently had their defects successfully closed without mortality. RESULTS: There were no early or late deaths at a follow-up of 38 +/- 16 months after the operation. Three patients (3/20, 15%) have had to undergo reintervention with balloon aortoplasty because of recurrent coarctation (gradient > 20 mm Hg) in 2 and resection of subaortic stenosis in 1. Late follow-up in the remaining patients reveals 1 with moderate subaortic stenosis (gradient = 43 mm Hg), 2 with mild aortic stenosis (gradient < 30 mm Hg), and 2 with mild to moderate mitral stenosis. At late follow-up, 16 patients (16/20, 80%) are completely free of symptoms and 4 (4/20, 20%) have mild residual symptoms. CONCLUSIONS: Biventricular physiology can be successfully achieved in neonates with small left heart structures and aortic arch obstruction with minimal mortality and excellent late functional results. Standard echocardiographic measurements used to predict the need for a univentricular repair in critical aortic stenosis are not valid for the neonate with aortic arch obstruction.