PubMed Health⌕ Search

Biomedical subjects

W Tworetzky

Publications and source records attributed to W Tworetzky.

13 recordsLinked to original sources

Factors affecting technical success of fetal aortic valve dilation.

OBJECTIVE: We have reported previously that valve dilation enhances growth of cardiac structures and may prevent hypoplastic left heart syndrome (HLHS) in fetuses with critical aortic stenosis. We aimed to investigate maternal/fetal factors which may affect the technical success of fetal valvuloplasty, and to describe perinatal complications of the procedure. METHODS: This was a descriptive series of 22 fetuses diagnosed with critical aortic stenosis developing into HLHS which underwent intervention by valvuloplasty. Initially this was attempted using a percutaneous approach; reassessment after our first five attempts, only one of which was successful, led to the introduction of the option of laparotomy. Technical success was defined as balloon inflation across the aortic annulus and a broader jet through the aortic valve as assessed by Doppler. Data collected included body mass index, demographic variables, ultrasound findings and postprocedure interventions. RESULTS: Technical success increased significantly if maternal laparotomy was an option (83.3% vs. 20.0%, P = 0.017). Laparotomy was performed in 66.6% (12/18) of cases. There was a learning curve that showed an increase in success rate and decrease in need for laparotomy over the 3-year study period. Neither the need for laparotomy nor the chances of technical success were predictable by gestational age, body mass index or placental location. Tocolysis was limited to perioperative prophylaxis; one woman experienced wound infection and fluid overload. Postoperatively, three fetuses died and two delivered prematurely, 2 and 7 weeks after intervention. CONCLUSION: Fetal aortic valvuloplasty can be performed with technical success, with low fetal loss rate and few maternal complications. While the need for laparotomy cannot be predicted, having it available as an option improves the technical success rate.

Adult↗

Improved surgical outcome after fetal diagnosis of hypoplastic left heart syndrome.

BACKGROUND: Hypoplastic left heart syndrome (HLHS) is frequently diagnosed prenatally, but this has not been shown to improve surgical outcome. METHODS AND RESULTS: We reviewed patients with HLHS between July 1992 and March 1999 to determine the influence of prenatal diagnosis on preoperative clinical status, outcomes of stage 1 surgery, and parental decisions regarding care. Of 88 patients, 33 were diagnosed prenatally and 55 after birth. Of 33 prenatally diagnosed patients, 22 were live-born, and pregnancy was terminated in 11. Of 22 prenatally diagnosed patients who were live-born, 14 underwent surgery, and parents elected to forego treatment in 8. Of 55 patients diagnosed postnatally, 38 underwent surgery, and 17 did not because of parental decisions or clinical considerations. Prenatally diagnosed patients were less likely to undergo surgery than patients diagnosed after birth (P:=0.008). Among live-born infants, there was a similar rate of nonintervention. Among patients who underwent surgery, survival was 75% (39/52). All patients who had a prenatal diagnosis and underwent surgery survived, whereas only 25 of 38 postnatally diagnosed patients survived (P:=0.009). Patients diagnosed prenatally had a lower incidence of preoperative acidosis (P:=0.02), tricuspid regurgitation (P:=0.001), and ventricular dysfunction (P:=0.004). They were also less likely to need preoperative inotropic medications or bicarbonate (P:=0.005). Preoperative factors correlating with early mortality included postnatal diagnosis (P:=0.009), more severe acidosis (P:=0.03), need for bicarbonate or inotropes (P:=0.008 and 0.04), and ventricular dysfunction (P:=0.05). CONCLUSIONS: Prenatal diagnosis of HLHS was associated with improved preoperative clinical status and with improved survival after first-stage palliation in comparison with patients diagnosed after birth.

Age Factors↗

Inhaled nitric oxide in neonates with persistent pulmonary hypertension.

To investigate the oxygenation and haemodynamic dose response to inhaled nitric oxide in neonates with persistent pulmonary hypertension (PPHN), we gave seven neonates nitric oxide and measured directly pulmonary arterial pressure. Inhaled nitric oxide produced peak improvement in oxygenation at 5 parts per million (ppm) whereas peak improvement in the pulmonary-to-systemic arterial pressure ratio did not occur until a nitric oxide dose of 20 ppm, which suggests that an Initial dose of 20 ppm is optimum for the treatment of PPHN.

Administration, Inhalation↗

Balloon arterioplasty of recurrent coarctation after the modified Norwood procedure in infants.

Coarctation of the reconstructed aorta after the modified Norwood procedure for hypoplastic left heart syndrome is a relatively common occurrence that can have significant adverse effects. From 1992-98, 65 infants with hypoplastic left heart syndrome or variants thereof underwent a modified Norwood procedure. Of the 50 survivors of Stage I palliation, 10 (20%) were subsequently diagnosed with clinically significant obstruction of the aortic arch at a median age of 5.1 months. Eight of these patients underwent coarctation balloon arterioplasty. All 8 patients underwent successful dilation of the coarctation, with a decrease in the pressure gradient from 43+/-20 to 4+/-5 mm Hg and an increase in aortic diameter at the site of obstruction from 3.5+/-0.5 to 7.0+/-1.0 mm (both P<0.001). There was also a significant increase in lower extremity systolic blood pressure. Although there was no immediate increase in cardiac output after dilation in most patients, ventricular function was improved in 3 patients within 24-48 hr of the procedure and in all but 2 at the most recent follow-up (median 2 years). Two patients developed bradycardia during wire placement that required cardiopulmonary resuscitation. Two others died suddenly during the follow-up period. All surviving patients have undergone subsequent palliative procedures; none have required repeat intervention for arch obstruction. We found a 20% incidence of coarctation in survivors of the modified Norwood procedure. Balloon arterioplasty is effective in relieving this obstruction, and should be carried out promptly upon diagnosis to minimize its deleterious effects on ventricular function. Balloon dilation, however, should be considered a high-risk procedure in these fragile infants, and special attention must be given to cardiovascular support.

Anastomosis, Surgical↗

Incidence and implications of systemic to pulmonary collaterals after bidirectional cavopulmonary anastomosis.

BACKGROUND: Systemic to pulmonary arterial collaterals often develop after bidirectional cavopulmonary anastomosis (BCPA). It has been proposed that such collaterals may be related to perioperative outcome and duration of effusions after the modified Fontan procedure. However, the incidence and significance of collaterals after BCPA remain uncertain. METHODS: To evaluate risk factors for, and significance of, such collaterals, we reviewed angiographic and clinical data for all 76 patients who underwent BCPA between January 1990 and June 1996 and had follow-up catheterization during or before 1997. RESULTS: The median age at BCPA was 10 months, and the median duration from BCPA to follow-up catheterization was 18 months. Arterial collaterals were detected on follow-up catheterization in 45 patients (59%). Factors associated with collateral development included a prior right-sided systemic-to-pulmonary arterial shunt, lower pre-BCPA end-diastolic ventricular pressure and pulmonary vascular resistance, and use and duration of cardiopulmonary bypass during the BCPA operation. Fourteen of the 45 patients (30%) underwent coil embolization of the collaterals. Forty-three patients have undergone extracardiac conduit Fontan, with 1 early and 1 late death. Collaterals were present in 22 of these patients, 7 of whom underwent pre-Fontan embolization. The duration from BCPA to Fontan was longer in patients with collaterals, but these patients were not more likely to have prolonged effusions than those without, and the duration of tube thoracostomy was significantly shorter in patients with collaterals. Embolization of collaterals did not affect the duration of effusions. CONCLUSIONS: Systemic-to-pulmonary arterial collaterals are common after BCPA. In contrast to prior reports, collaterals were not associated with a higher incidence of prolonged effusions after the Fontan procedure in our experience, and did not correlate with poor outcome.

Collateral Circulation↗

Issues and outcomes in the management of supravalvar aortic stenosis.

BACKGROUND: Supravalvar stenosis of the aorta is an uncommon congenital cardiac anomaly that involves not only the supravalvar aorta but the entire aortic root. Despite considerable attention to the importance of maintaining the integrity of the aortic root during supravalvar reconstruction, there has been little focus on the management of other components of the aortic root and left ventricular outflow tract, including the aortic valve, subvalvar region, and coronary arteries. METHODS: We reviewed the records of 36 consecutive patients with supravalvar aortic stenosis who underwent repair from 1992-1998 (median age, 4 years). Discrete stenosis was present in 29 patients, whereas the remaining 7 had the diffuse form of the disease. Associated anomalies of the aortic root and adjacent structures were present in 23 patients. The median pressure gradient across the left ventricular outflow tract was 70 mm Hg. Supravalvar stenosis was relieved by extended aortoplasty with a Y-shaped patch in 18 patients, resection of the stenotic segment of ascending aorta at the sinotubular junction with end-to-end anastomosis of the ascending aorta in 7, the Ross procedure in 4, and other techniques in 7. Additional procedures included aortic valvuloplasty in 10 patients, resection of subvalvar stenosis in 11, and procedures on the coronary arteries in 2. RESULTS: There was 1 perioperative death, and no reoperations or other significant complications. During follow-up (median 33 months), there were no deaths and 3 reoperations for replacement of the aortic valve with a pulmonary autograft (n = 1) or mechanical prosthesis (n = 2). The median pressure gradient across the left ventricular outflow tract was 10 mm Hg. CONCLUSIONS: In patients with supravalvar aortic stenosis, abnormalities of the aortic valve, subaortic region, and coronary arteries are frequently present as well. Management of these issues is as critical to the long-term outcome of these patients as reconstruction of the supravalvar aorta. Aggressive valvuloplasty may help decrease the incidence of late aortic valve replacement, whereas the Ross procedure may be a preferable approach in some patients with complex outflow tract obstruction.

Adolescent↗

Pulmonary blood flow alters nitric oxide production in patients undergoing device closure of atrial septal defects.

OBJECTIVE: To determine the effect of pulmonary blood flow (Qp) on nitric oxide (NO) production in patients with increased Qp due to an atrial septal defect (ASD). BACKGROUND: Alterations in pulmonary vascular NO production have been implicated in the development of pulmonary hypertension secondary to increased Qp. In vitro, acute changes in flow or shear stress alter NO production. However, the effect of Qp on lung NO production in vivo is unclear. METHODS: Nineteen patients (2.4-61 years of age, median 17) with secundum ASD undergoing device closure were studied. Before, and 30 min after ASD closure, exhaled NO and plasma nitrate concentration were measured by chemiluminescence (NOA 280, Sievers, Boulder, Colorado). RESULTS: Before ASD closure, all patients had increased Qp (Qp: systemic blood flow [Qs] of 2.0 +/- 0.7) and normal mean pulmonary arterial pressure (13.4 +/- 3.1 mm Hg). Atrial septal defect device closure decreased Qp from 6.0 +/- 2.5 to 3.6 +/- 1.3 L/min/m2 (p < 0.05). Mean pulmonary arterial pressure was unchanged. Associated with the decrease in Qp, both exhaled NO (-22.1%, p < 0.05) and plasma nitrate concentrations (-17.9%, p < 0.05) decreased. CONCLUSIONS: These data represent the first demonstration that acute changes in Qp alter pulmonary NO production in vivo in humans. Exhaled NO determinations may provide a noninvasive assessment of pulmonary vascular NO production in patients with congenital heart disease. Potential correlations between exhaled NO, pulmonary vascular reactivity and pulmonary hypertension warrant further study.

Adolescent↗

Congenital obstructive lesions of the right aortic arch.

BACKGROUND: In the setting of normal cardiac situs, a right-sided aortic arch is uncommon. When a right arch does occur, it is typically in conjunction with other congenital cardiovascular anomalies, especially defects with abnormal right ventricular outflow. Congenital obstruction of a right arch, caused by coarctation, interruption, or cervical arch, is extremely rare. METHODS: We reviewed our experience and all reported cases of right aortic arch with coarctation of the aorta, interrupted arch, or obstruction of a cervical arch in the setting of normal cardiac situs and topology. RESULTS: Since 1992, 4 such patients have undergone repair at our institution, including 1 with interrupted arch, 1 with coarctation of a mirror image arch, and 2 with obstruction of a cervical arch. In addition to these 4 patients, 38 others have been described in the published reports: 15 with interrupted arch, 19 with coarctation, and 4 with obstruction of a cervical arch. Associated cardiac defects were uncommon, except for ventricular septal defect in patients with interrupted arch, but abnormalities of the brachiocephalic vessels were frequent. Except for most of the patients with interrupted right arch, the majority of patients described have undergone successful surgical repair. CONCLUSIONS: Although obstructive arch lesions are often grouped together, the etiologies of coarctation of the aorta, interrupted arch, and cervical arch with obstruction almost certainly differ. The rarity of such lesions among patients with right aortic arch may be explained in part by the fact that the fetal hemodynamic conditions associated with persistence of a right arch do not facilitate flow-related arch obstruction. In this review, we discuss these issues in detail, along with specific surgical considerations in the management of obstruction lesions of the right aortic arch.

Aorta, Thoracic↗

Multiple ventricular septal defects: how and when should they be repaired?

BACKGROUND: Congenital heart lesions with multiple ventricular septal defects remain a surgical challenge. Traditional approaches often rely on either ventriculotomy for exposure or palliation with pulmonary artery banding. However, indications for repair versus palliation and for various approaches to surgical exposure are not clearly defined. METHODS: From July 1992 to January 1998, 45 patients with multiple (>/=2) ventricular septal defects (37 with associated lesions) underwent surgery. Median age was 86 days; all but 4 patients were infants. The mean number of defects was 3.7, and almost half of the patients had more than 3 defects. Apical muscular defects were present in 62% of patients. Thirty-one patients underwent primary complete repair through a right atriotomy or trans-semilunar valve approach (group 1), 8 had palliation (group 2), and 6 underwent complete repair after prior palliation elsewhere (group 3). No patient had a ventriculotomy. RESULTS: One early death occurred in a group 1 patient. Four patients who had had palliation (50%) underwent early reoperation for pulmonary artery band revision because of failure to thrive or band removal after spontaneous closure of the defects. At follow-up (median 22 months), there was 1 death in a group 2 patient (palliation) and 1 other group 2 patient required cardiac transplantation. The only late reoperation was for removal of the pulmonary artery band and closure of multiple apical defects in a group 2 (palliation) patient. No patients who underwent repair have hemodynamically significant residual defects. CONCLUSIONS: In our experience, palliation of multiple ventricular septal defects is associated with greater morbidity than primary repair. Multiple defects can almost always be repaired adequately in early infancy without ventriculotomy, although "Swiss-cheese" septum may be an indication for palliation.

Child, Preschool↗

Echocardiographic diagnosis alone for the complete repair of major congenital heart defects.

OBJECTIVES: The study was done to determine the diagnostic accuracy of echocardiography alone in the preoperative diagnosis of children with major congenital heart defects undergoing primary complete repair. BACKGROUND: Although echocardiography is well established as the first-line imaging technique for the diagnosis of all forms of congenital heart disease, most institutions continue to perform cardiac catheterization prior to complete repair of more complex defects. METHODS: To determine the diagnostic accuracy of echocardiography alone and echocardiography plus catheterization, we reviewed the records of 503 children with major congenital heart defects who underwent primary complete repair at our institution between July 1992 and June 1997. We included children with transposition of the great arteries, tetralogy of Fallot, double-chamber right ventricle, interrupted aortic arch, aortic coarctation, atrioventricular septal defect, truncus arteriosus, aortopulmonary septal defect, and totally anomalous pulmonary venous return. We excluded children with less complex defects such as isolated shunt lesions, as well as those with the most complex defects that would require surgical palliation (e.g., functional univentricular heart). We defined major errors as those that increased the surgical risk and minor errors as those that did not. Errors in diagnosis were determined at surgery. RESULTS: Eighty-two percent of children (412 of 503) underwent surgery after preoperative diagnosis by echocardiography alone. There were 9 major (2%) and 10 minor errors in the echocardiography alone group and 7 major and 5 minor errors in the echocardiography plus catheterization group. The most common type of error was misidentification of coronary artery anatomy in patients with transposition of the great arteries. No error in either group resulted in surgical morbidity or mortality. CONCLUSIONS: This study suggests that echocardiography alone is an accurate tool for the preoperative diagnosis of major congenital heart defects in most children undergoing primary complete repair, and may obviate the need for routine diagnostic catheterization.

Adolescent↗

Early and late results after repair of aortopulmonary septal defect and associated anomalies in infants <6 months of age.

The Richardson classification system for aortopulmonary septal defect (APSD) includes simple defects between the ascending aorta and pulmonary trunk (type I), defects extending distally to include the origin of the right main pulmonary artery (type II), and anomalous origin of the right main pulmonary artery from the ascending aorta with no other aortopulmonary communication (type III). These are rare lesions that must be repaired in early infancy to avoid development of pulmonary vascular disease. Few reports have focused on patients with complex, associated lesions who underwent repair in early infancy. Between 1972 and 1995, 24 patients with Richardson type I (n = 11), II (n = 7), or III (n = 6) defects underwent repair at ages ranging from 2 to 172 days (median 34). Twelve patients had complex, associated anomalies, including interrupted or hypoplastic arch (n = 9), tetralogy of Fallot with (n = 1) or without (n = 1) pulmonary atresia, and transposition of the great arteries (n = 1). The most recent 7 patients were diagnosed by echocardiography without cardiac catheterization. There were no early or late deaths among the 12 patients with simple APSD. Four patients with complex, associated lesions died in the early postoperative period and another died 4 months after surgery. All 6 surviving patients with interrupted arch have had recurrent obstruction at the arch repair site, although reintervention for this reason has been performed in only 2 patients. Altogether, 6 early survivors have required reintervention, and all survivors are in New York Heart Association class I at follow-up ranging from 2 to 25 years. Thus, long-term survival after repair of APSD in early infancy is excellent. Late sequelae are likely to be related either to associated lesions or to obstruction at the APSD repair site. Almost all cases of APSD in young infants can be diagnosed and evaluated by echocardiography without catheterization.

Aorta, Thoracic↗