Barriers to the delivery of adequate hemodialysis in ESRD Network 4.

Dialysis dose has been established as a determinant of morbidity and mortality in chronic hemodialysis patients. To identify remediable barriers to the delivery of adequate hemodialysis, we examined factors that affected adherence to prescribed dialysis dose. End-Stage Renal Disease (ESRD) Network 4 facilities that fell into the lowest quintile in measures of dialysis adequacy were studied. At the time of this study, Network 4 was composed of 178 dialysis facilities in Delaware and Pennsylvania. Those 29 facilities had an average delivered urea reduction ratio (URR) of <0.67 and/or 71% of patients with a URR of 0.65. (The mean URR value of Network 4 was 0. 699 with a compliance ratio of 80%.) Dialysis treatment sheets were reviewed for all patients in the 29 facilities for all treatments during a calendar week. Predialysis and postdialysis blood urea nitrogen (BUN) values from 1 treatment during this week were used to calculate URR and Kt/V. A total of 1,339 patients with a mean age of 61.9 +/- 15.1 years and a mean duration of ESRD of 3.4 +/- 3.3 years were dialyzed in the 29 units. Mean prescribed duration of dialysis (T) was 219 +/- 26 min. with a mean blood flow rate (BFR) of 393 +/- 62 mL/min. Concordance between the prescribed and delivered T (-5 min), BFR (-50 mL/min), and hemodialyzer were assessed, by patient, for each treatment (Tx). Characteristics of a delivered Kt/V < 1.2 were duration <4 hours, BFR < 350 mL/min, patient weight > 100 kg, and delivered BFR 50 mL/min less than prescribed BFR. Multivariate analysis of the relationship between delivered dose of dialysis and patients and treatment characteristics identified black race, male gender, and younger age as demographic factors associated with low delivered dose. Potential remediable barriers identified by this analysis included reduced treatment time (>10%) and use of catheters for angioaccess. These data suggest components of the dialysis process that might be targeted in future quality improvement projects to improve the adequacy of dialysis delivery.

Improving compliance with the dialysis prescription as a strategy to increase the delivered dose of hemodialysis: an ESRD Network 4 quality improvement project.

Delivery of an inadequate dose of hemodialysis is associated with a significant increase in the relative risk of both hospitalization and death. We hypothesized that noncompliance with the dialysis prescription, defined as failure to achieve the prescribed blood flow, failure to dialyze for the prescribed duration, or failure to use the prescribed dialyzer, was a significant factor in patients not achieving a urea reduction ratio (URR) of > or =0.65. We identified the 29 dialysis facilities in ESRD Network 4 that had the lowest average URR and/or lowest percent of patients with a URR > or =0.65 based on quarterly data reports. Each facility was surveyed by review of all dialysis treatment sheets from a single week by network staff to evaluate for noncompliance with the dialysis prescription. Facility-specific data were reported back to each facility. Each facility was required to develop a facility-specific quality improvement plan after receiving intensive education on the quality improvement process. After 9 months the facilities were resurveyed. Although the compliance with the dialysis prescription decreased from 54.0% to 53.6% (P =.026), the delivered URR increased from 0.679 +/- 0.072 to 0.688 +/- 0.070 (P =.026) with an increase in the percentage of patients with a URR > or = 0.65 from 69.7% to 75% (P =.0096). Kt/V increased from 1.37 +/- 0.26 to 1.41 +/- 0.27 (P =. 0001). Analysis of the process changes instituted by the individual facilities showed an increase in the prescribed dose of dialysis. Thus, although the process goal of improved compliance with the dialysis prescription was not achieved, the outcome goal of an increased delivered dose of dialysis was met through an alternative process change of an augmented dialysis prescription.

Echocardiographic predictors of coronary artery pathology in pulmonary atresia with intact ventricular septum.

Coronary artery pathology is a major determinant of treatment strategy and outcome in patients with pulmonary atresia and intact ventricular septum (PA/IVS). For this reason, infants with PA/IVS routinely undergo preoperative cardiac catheterization. The goal of this study was to identify echocardiographic predictors of coronary artery pathology in infants with PA/IVS. The initial preoperative echocardiograms of 30 consecutive infants with PA/IVS (median age at diagnosis 1 day) were reviewed for indexes predicting the degree of coronary pathology. The tricuspid valve (TV) annulus diameter Z- score was determined and evidence of abnormal flow in the coronary arteries by Doppler was evaluated. Coronary pathology was defined by angiography and graded as: 0 = no fistulae; 1 = fistulae/no right ventricular (RV)-dependent coronary arteries; 2 = fistulae with 1 RV-dependent coronary; 3 = fistulae with >/=2- vessel RV-dependent coronary arteries. Outcome was classified as: 2 ventricles, "1.5" ventricles, and 1 ventricle. By angiography, 30% of the patients had grade 0 coronary pathology, 30% had grade 1, 20% had grade 2, and 20% had grade 3. There was 1 death in a patient with grade 3 coronary pathology. Among the survivors (median age at follow-up 28. 6 months), biventricular circulation existed in 12 patients (41%), 7 patients (24%) were 1.5, and 10 (34%) were 1 ventricle. All patients with TV Z-score -2.5. The sensitivity, specificity, positive, and negative predictive values of TV Z-score

Early results and medium-term follow-up of stent implantation for mild residual or recurrent aortic coarctation.

BACKGROUND: Optimal timing and mode of treatment for patients with aortic coarctation remains controversial, particularly when the degree of obstruction is mild. Surgery, balloon dilatation, and stent implantation have all proven effective in the treatment of moderate or severe obstruction. In this report, we describe the use of stents to treat coarctation in a heterogeneous population, including patients with relatively mild obstruction. METHODS: Retrospectively, we studied the results of stent implantation in 33 patients, children and young adults, who underwent catheterization for treatment of coarctation. Patients with isolated coarctation, as well as those with associated cardiac defects, were included. The median systolic pressure gradient of our patients was 25 mm Hg. RESULTS: Patients had an acute decrease in systolic blood pressure gradient (25 mm Hg to 5 mm Hg, P <.001) and an increase in lumen diameter (8 mm to 13 mm, P <.001). When 16 patients were recatheterized during the follow-up period, gradients remained decreased (30 mm Hg to 14 mm Hg, P <.001) compared with prestent values. Ventricular end-diastolic pressure, which was increased in 82% of patients at the time of initial catheterization, decreased from 17 mm Hg to 14 mm Hg (P =.002). Although the procedure was generally safe, serious complications did occur. CONCLUSIONS: Stent implantation represents a therapeutic option that can safely and effectively reduce gradient in challenging patients with mild postoperative coarctation. Furthermore, our data suggest that aortic obstruction often coexists with ventricular diastolic dysfunction in these patients and that relief of obstruction may play a role in improvement of function.

Left superior vena cava connection to unroofed coronary sinus associated with positional cyanosis: successful transcatheter treatment using Gianturco-Grifka vascular occlusion device.

A persistent left superior vena cava connection to an unroofed coronary sinus is a rare cardiac anomaly that is associated with a variable degree of cyanosis. We report an infant with this condition and the unusual feature of cyanosis dependent on head position. When the patient's head was rotated to the left, he developed severe stenosis of the left internal jugular vein, enlarged cervical collateral veins that connected to the right superior vena cava and had an oxygen saturation 95%. When the patient's head was rotated to the right, the left internal jugular vein was widely patent and systemic oxygen saturation decreased to 87%. There was no right ventricular volume overload. Temporary occlusion of the left superior vena cava documented tolerable proximal venous pressure. Cyanosis was relieved by transcatheter closure of the left superior vena cava with a Gianturco-Grifka vascular occlusion device. Cathet. Cardiovasc. Intervent. 48:369-373, 1999.

Repeat balloon dilation of congenital valvar aortic stenosis: immediate results and midterm outcome.

While balloon dilation (BD) has become the initial treatment for congenital valvar aortic stenosis (CVAS) at many institutions, repeat BD for recurrent obstruction has been reported only in a few. Between January 1985 and December 1996, 298 patients (70 neonates) underwent BD, 34 of whom underwent a repeat BD without mortality. A greater proportion of neonates had a repeat BD (26% vs. 8%, P < 0.001). At repeat BD (1 day-7.5 years post initial BD), the mean peak-to-peak gradient was reduced from 67+/-24 to 36+/-16 mm Hg (P < 0.0001). Aortic regurgitation (AR) increased immediately in 26%, being moderate or more in 24%. During a mean follow-up of 5.2 years, there was one surgically related death. Of the 33 survivors, 6 had surgery for residual stenosis and/or AR. Among the remaining 27 patients, 96% were asymptomatic, the peak instantaneous aortic valve Doppler gradient was 50+/-15 mm Hg with AR absent in 8%, mild in 62%, and moderate or more in 31%. In conclusion, repeat BD is effective and without mortality. AR was at least moderate in 24% of patients immediately after a second BD. Repeat BD was more common in patients who underwent the initial BD as neonates.

Preoperative management of pulmonary venous hypertension in hypoplastic left heart syndrome with restrictive atrial septal defect.

A severely restrictive atrial septal defect (ASD) in neonates with hypoplastic left heart syndrome (HLHS) results in pulmonary venous hypertension, pulmonary edema, and intractable hypoxia. Between January 1983 and June 1998, 21 of 355 neonates presenting with HLHS (5.9%) underwent cardiac catheterization at median age 1 day (range 0 to 25), for creation or enlargement of a restrictive or absent interatrial communication. One patient died during preliminary angiography. Three underwent blade septostomy with 2 procedure-related deaths, and 1 had balloon atrial septostomy (BAS); all 4 died before surgical intervention. Fifteen underwent Brockenbrough atrial septoplasty with transatrial needle puncture and serial balloon dilations of the new ASD, 5 after unsuccessful BAS. The most recent patient had a stent placed across the atrial septum after transatrial needle puncture. In the 16 patients treated with septoplasty or stent, oxygen saturation increased from 50 +/- 4% to 83 +/- 2% (p <0.0001) and transatrial pressure gradient decreased from 16 +/- 1 to 6 +/- 1 mm Hg (p <0.0001). One patient died awaiting transplantation, supportive care only was requested in 1, and 14 underwent stage 1 palliation. Eight of 14 (57%) survived to hospital discharge. Six of 7 (86%) survived bidirectional Glenn and the 3 who have undergone fenestrated Fontan are alive. In neonates with HLHS, a restrictive ASD resulting in profound cyanosis demands urgent intervention. BAS is frequently unsuccessful and blade septostomy has high mortality. Pulmonary venous hypertension can be adequately relieved by Brockenbrough atrial septoplasty or stenting, allowing stabilization before reconstructive surgery or while awaiting transplant.

Transvascular balloon dilation for neonatal critical aortic stenosis: early and midterm results.

OBJECTIVES: We evaluated our immediate and midterm (mean 4.3 years) results of balloon dilation of critical valvular aortic stenosis in 33 neonates. BACKGROUND: Balloon dilation has been used as an alternative to surgical treatment. Reports to date consist of small series (largest 16 babies) with short-term follow-up (longest 4.8 years). METHODS: From 1985 to 1991, 33 neonates had dilation at a mean age of 13 days and a mean weight of 3.4 kg. Nineteen of the neonates (58%) were intubated and received prostaglandins, and 94% had other cardiac abnormalities. RESULTS: The dilation was completed retrograde in 31 of the neonates (umbilical artery in 11 and femoral artery in 20) and anterograde (femoral vein) in 2. The average immediate peak gradient and left ventricular end-diastolic pressure reductions were 54% and 20%, respectively. The overall mortality rate was 12% (three early deaths and one late). All 20 neonates dilated through a femoral artery initially had pulse loss with restoration in 35% after thrombolytic therapy. At 8.3 years, survival and freedom of reintervention probability rates were 88% and 64%, respectively. At mean 4.3 years of follow-up, 83% of the survivors were asymptomatic; Doppler study revealed a maximal instantaneous gradient < 50 mm Hg in 65% of neonates and significant aortic regurgitation in 14%. CONCLUSIONS: This study confirms that dilation of aortic stenosis in neonates is effective; reintervention (mostly redilation) is frequent (40%); and midterm survival is encouraging (88%).

Tetralogy of Fallot with diminutive pulmonary arteries: preoperative pulmonary valve dilation and transcatheter rehabilitation of pulmonary arteries.

OBJECTIVES: This study sought to determine the results of a novel transcatheter management approach in tetralogy of Fallot with diminutive pulmonary arteries. BACKGROUND: Tetralogy of Fallot with diminutive pulmonary arteries and severe pulmonary stenosis is rare and resembles tetralogy of Fallot with pulmonary atresia: There is a high incidence of aortopulmonary collateral channels, arborization abnormalities, stenoses and need for multiple operations. Because a combined catheter-surgery approach facilitates repair in these patients, such an approach may benefit those with diminutive pulmonary arteries and pulmonary stenosis. METHODS: Clinical, catheterization and surgical data were studied retrospectively for 10 such patients undergoing preoperative pulmonary valve balloon dilation, among other transcatheter interventions, from January 1989 to January 1995. RESULTS: Initially, the Nakata index ranged from 20 to 98 mm2/m2 (mean 67 +/- 28 mm2/m2). The pulmonary valve was first balloon dilated (mean balloon/annulus 1.5 +/- 0.3), and the mean initial valve annulus Z score (-4.0 +/- 1) increased to -33 +/- 1.1 (p < 0.01) Other interventions included branch pulmonary artery balloon dilation (7 patients, 23 vessels) and coil embolization of aortopulmonary collateral channels (8 patients, 31 collateral channels). At preoperative follow-up catheterization, the mean pulmonary annulus Z score was -3.1 +/- 0.7, and the Nakata index increased to 143 +/- 84 mm2/m2 (p < 0.03). All patients underwent complete surgical repair successfully. At a mean follow-up period of 2.6 +/- 2 years, right ventricular pressure was < 70% systemic in all patients and < 50% systemic in seven. CONCLUSIONS: In patients with tetralogy of Fallot, severe pulmonary stenosis and diminutive pulmonary arteries, initial pulmonary valve balloon dilation increases the annulus Z score and anterograde pulmonary blood flow and facilities simultaneous coiling of aortopulmonary collateral channels and access for branch pulmonary artery dilation, all of which results in pulmonary artery growth, simplifying surgical management.

Midterm results of balloon dilation of congenital aortic stenosis: predictors of success.

OBJECTIVES: We evaluated patient and procedural characteristics that influence the midterm success of balloon dilation of congenital aortic stenosis. BACKGROUND: Balloon dilation is a new treatment for congenital aortic stenosis. Factors that influence midterm success are unknown. METHODS: We performed a retrospective review of 148 children >1 month old who underwent balloon dilation for aortic stenosis. RESULTS: Balloon dilation was successful in 87% of patients, with a procedural mortality rate of 0.7%. The average immediate peak to peak gradient reduction was 56.4 +/- 19.9% (mean +/- SD). Prior valvotomy was the only factor that significantly reduced the immediate gradient reduction after dilation (47.1 +/- 21.8% vs. 57.8 +/- 19.6%, p < 0.01). Survival after dilation was 95% at 8 years. Seventy-five percent of patients were free of repeat intervention 4 years after dilation, whereas 50% remained free of repeat intervention at 8 years. Asymmetrically thick valve leaflets (risk ratio [RR] 0.17, p < 0.01) and prior aortic valvotomy (RR 0.35, p = 0.02) decreased the risk of repeat intervention. Aortic regurgitation grade > or = 3 (RR 4.27, p = 0.04) and residual gradient after dilation (RR 1.63 for 10 mm Hg, p < 0.01) increased the risk. CONCLUSIONS: The 8-year survival rate after dilation was 95% with 50% of patients free of repeat intervention. Factors that increased the risk for repeat intervention included symmetrically thin or thick aortic valve leaflets, regurgitation grade > or = 3 after dilation and a high residual gradient after dilation. The incidence of repeat intervention after dilation was high owing to its palliative nature.

New developments in intracardiac and intravascular devices for congenital heart disease.

Techniques of transcatheter device placement for treatment of pediatric congenital heart disease have developed substantially since their introduction 20 years ago. Patent ductus arteriosus occlusion can be accomplished by umbrella deployment or coil placement. Intracardiac defects can be closed with umbrella or buttoned devices. Stenoses of vessels or conduits that are only temporarily relieved with balloon dilation can be effectively expanded with intravascular stents. Recent procedural modifications have been introduced in an attempt to minimize the size of the delivery sheath and reduce complications that can arise from device embolization. Transcatheter device placement can be an important adjunct to surgery for correction or palliation of congenital heart lesions.

Prolongation of RV-PA conduit life span by percutaneous stent implantation. Intermediate-term results.

BACKGROUND: Right ventricle-to-pulmonary artery (RV-PA) homografts and bioprosthetic conduits are commonly used to palliate various types of complex congenital heart disease. These conduits frequently develop progressive obstruction and require surgical replacement. This report reviews our experience implanting balloon-expandable stents to relieve conduit obstruction and delay reoperation. METHODS AND RESULTS: A retrospective review identified 44 patients who underwent placement of 48 stents in obstructed RV-PA conduits. Median patient age was 6.9 years (range, 7 months to 30 years), and median follow-up time was 14.2 months (range, 0 to 48 months). Stent implantation initially decreased the RV-PA pressure gradient from 61.0 +/- 16.9 to 29.7 +/- 11.9 mm Hg (P < or = .001) and the right ventricular-to-systemic arterial pressure ratio from 0.92 +/- 0.17 to 0.63 +/- 0.20 (P < or = .001). The diameter of the stenotic region expanded from 9.3 +/- 3.5 to 12.3 +/- 3.3 mm in the anteroposterior view (P < or = .001) and from 6.6 +/- 2.9 to 10.9 +/- 2.5 mm in the lateral view (P < or = .001). During the follow-up period, 2 patients had their stents redilated, 7 had additional conduit stents deployed, and 14 underwent surgical replacement of their conduits. Actuarial freedom from conduit reoperation was 65% at 30 months postprocedure. Seven patients were found to have fractured stents on follow-up, suggesting an important role for external compressive forces in conduit failure. Recatheterization in 16 patients a median of 11.8 months (3 to 48 months) postprocedure demonstrated hemodynamic evidence of recurrent obstruction despite sustained enlargement at the previously stented sites. Complications included stent displacement (n = 1), bacterial endocarditis (n = 1), and false aneurysm formation (n = 1). One patient died awaiting conduit replacement surgery. CONCLUSIONS: Stent implantation in obstructed RV-PA conduits results in significant immediate hemodynamic and angiographic improvement. In a subgroup of patients, the procedure prolongs conduit life span by several years and increases the interval between conduit reoperations. Recurrent obstruction is caused by external compression and progressive stenosis outside the stented region.

Coronary artery abnormalities detected at cardiac catheterization following the arterial switch operation for transposition of the great arteries.

Because the arterial switch operation has become the routine surgical approach for transposition of the great arteries, there is increasing awareness of adverse sequelae in some survivors. For the arterial switch to be considered the procedure of choice for transposition of the great arteries, long-term patency and normal function of the translocated coronary arteries must be achieved. We reviewed the cineangiograms and hemodynamic data in 366 patients who underwent postoperative catheterization after arterial switch operation. Of these, 13 patients (3%) had previously unsuspected coronary abnormalities diagnosed angiographically. No patient had noninvasive evidence of resting systolic dysfunction. Findings included left main coronary artery stenosis (n = 3) or occlusion (n = 2), anterior descending coronary artery stenosis (n = 1) or occlusion (n = 2), right coronary artery stenosis (n = 1) or occlusion (n = 1), and small coronary artery fistulas (n = 3). One patient died suddenly 3.3 years after surgery, 1 patient is lost to follow-up, and the remaining 10 patients are alive and asymptomatic up to 11 years after surgery.

Transcatheter closure of ventricular septal defects: hemodynamic instability and anesthetic management.

The technique of transcatheter ventricular septal defect (VSD) device closure may be associated with significant hemodynamic instability. The anesthetic records and catheterization data of 70 consecutive transcatheter VSD closures between February 1989 and September 1992 were reviewed, and risk factors associated with hemodynamic instability evaluated. In 28 of 70 procedures (40%), hypotension (> 20% decrease in systolic blood pressure from baseline) occurred; 12 responded to administration of fluids intravascularly alone, whereas 16 patients required additional acute resuscitation. Significant dysrhythmias occurred during 20 (28.5%) anesthetics associated with hypotension and requiring treatment or catheter withdrawal. ASA physical status, precatheterization indication for device placement, and patient size were not predictive of hemodynamic instability during the procedure. Blood transfusions were necessary in 38 (54.4%) cases and were size-related, with patients weighing less than 10 kg requiring a significantly larger transfusion volume (25.1 +/- 12.4 mL/kg). After 35 procedures (50%) patients were admitted directly to the intensive care unit (ICU) due primarily to hemodynamic instability or procedure duration; 24 (68%) required mechanical ventilation. No deaths occurred; there was no late morbidity due to catheterization-related events. Intravenous sedation was used for the initial catheterizations, maintained with a combination of midazolam, ketamine, and morphine. Subsequently general intravenous or inhaled anesthesia was predominantly used during transesophageal echocardiography and internal jugular vein cannulation. We conclude that hemodynamic instability is common during device closure of VSDs, and is likely to be an inescapable feature of these procedures in many patients because of the technique necessary for device placement.

Intraaortic spring coil loops: early and late results.

OBJECTIVES: Our aim was to determine the late fate of intraaortic spring coil loops after embolization of aortopulmonary vessels. BACKGROUND: In some aortopulmonary collateral vessels and patent ductus arteriosi, the narrowest segment is close to the aorta; coils used to close such vessels will "straddle" the lesion, allowing one or more coil loops to protrude into the aortic lumen. The consequences of this procedure are unknown. METHODS: We reviewed the cineangiograms of all patients who had at least one aortopulmonary collateral vessel or patent ductus arteriosus closure between January 1, 1988 and August 31, 1993. From this group, 53 patients had multiple-plane angiographic evidence of intraaortic coil loops. All subsequent cineangiograms were reviewed to determine coil position or movement and evidence of recanalization or endothelial coverage of the coil loop. We also reviewed each hospital record or communicated directly with referring physicians to identify any subsequent complications such as emboli or endocarditis. RESULTS: Of the 53 patients with intraaortic coil loops, 49 patients had closure of one or more aortopulmonary collateral vessels (59 vessels), and 4 had closure of a patient ductus arteriosus (4 vessels). Patient follow-up ranged from 1 day to 66 months (median 20 months); follow-up was not available in 6 patients. Five of the 53 patients (9.3%; 95% confidence limits [CL] 3.1% to 20.7%) died at operation or of end-stage heart failure. Patients with late angiography had no residual flow in 31 of 35 aortopulmonary collateral vessels (88.6%; 95% CL 73.3% to 96.8%), and 0.5 mm separated the coil and aortic contrast column in all 12 coils with adequate angiography, suggesting endothelial coverage of the intraaortic coil loop. No episodes of stroke, embolic events, endocarditis or coil migration were reported. CONCLUSIONS: Although coil occlusion of aortopulmonary collateral vessels or patent ductus arteriosi may produce intraaortic coil loops, endothelialization appears routine. No late complications associated with intraaortic coil loops were observed.

Balloon dilation of critical valvar pulmonary stenosis in the first month of life.

Between 1985 and 1992, 36 consecutive neonates, aged 1-29 days, weight 2.4-5.0 kg, with critical valvar pulmonary stenosis underwent attempted balloon dilation (BD). At catheterization, 30 were on prostaglandin (PGE1) therapy and 20 were intubated. The valve was successfully crossed and dilated in 34/36 (94%), including three with an echocardiographic diagnosis of valvar pulmonary atresia and a right ventricle of adequate size. The valve was first dilated with a 2- to 5-mm balloon and then with serially larger ones (up to 12 mm) to a final balloon/annulus value of 126%. The RV/systemic pressure value fell from 150 +/- 32 to 83 +/- 30%, O2 saturation rose from 91 +/- 6% to 96 +/- 4%, and PGE1 was discontinued at the end of the procedure. There were 11 complications (31%) including one early death from sepsis and necrotizing enterocolitis, endocarditis in another, two myocardial perforations, one femoral-iliac vein tear, and one transient pulse loss. A repeat BD was carried out in five patients, two of whom subsequently had surgery. At follow-up (33 +/- 23 months), the 31 patients managed by BD alone were well and had echocardiographic gradients of < 30 mm Hg in 90% and pulmonary regurgitation, considered mild in most, in 52%. In neonates with critical valvar pulmonary stenosis, we believe BD mortality is less than with surgery and is the treatment of choice.

Transesophageal echocardiographic guidance of transcatheter ventricular septal defect closure.

OBJECTIVES: This report describes transesophageal echocardiographic guidance of transcatheter closure of ventricular septal defects and its value as an adjunct to fluoroscopy and angiography in this procedure. BACKGROUND: Experience with transcatheter closure of ventricular septal defects has identified a diverse group of patients in whom it may be the procedure of choice. Although facilitating other interventional procedures, such as transcatheter closure of atrial septal defects, the value of transesophageal echocardiographic guidance for transcatheter ventricular septal defect closure has not been documented. METHODS: All patients who underwent ventricular septal defect closure with transesophageal echocardiographic guidance before November 1992 were included. Angiograms and echocardiograms were reviewed to evaluate device position and relation to valve tissue during placement and to assess residual flow after device implantation. The ability of transesophageal echocardiography to assess these variables was compared with fluoroscopy and angiography. RESULTS: Transesophageal echocardiographic guidance was used in 31 of the 83 catheterizations involving transcatheter ventricular septal defect closure performed between February 1990 and November 1992. Under transesophageal echocardiographic guidance, 45 devices were implanted: 23 in muscular ventricular septal defects, 17 in residual postoperative patch margin defects and 5 in other ventricular septal defects. Transesophageal echocardiographic guidance enhanced assessment of device position and proximity to valve structures and markedly improved assessment of residual flow. Assessment of residual flow with transesophageal echocardiography eliminated the need for multiple angiograms in some patients. Combining transesophageal echocardiography with fluoroscopy and angiography provided the most information. CONCLUSIONS: Transesophageal echocardiography facilitates transcatheter closure of ventricular septal defects by improving assessment of device position and effectiveness of closure. It is indicated when device placement is likely to be difficult or may interfere with valve structures or when multiple interventional procedures are anticipated.

Balloon aortic valvuloplasty in the young adult with congenital aortic stenosis.

Although balloon aortic valvuloplasty (BAV) is effective in the acute management of valvar aortic stenosis (AS), sustained benefit of this technique has been shown to vary in differing age groups. The role of BAV in the young adult with congenital, nondegenerative AS is poorly defined. The catheterization results and follow-up echocardiographic data were reviewed for all patients (n = 18) between the ages of 17 and 40 years (mean 23 +/- 7) undergoing BAV at our institution between March 1986 and January 1992. Peak-to-peak systolic ejection gradient was reduced by 55%, from 85 +/- 29 to 38 +/- 17 mm Hg (p < 0.001). Aortic valve area increased from 0.9 +/- 0.2 to 1.1 +/- 0.3 cm2 (p = 0.003). Results of dilation were inadequate in 2 patients. There were no deaths, myocardial infarction, or embolic events. The 16 "effectively" dilated patients were followed with serial echocardiography for a period of 1 to 82 months, demonstrating persistent gradient relief in most patients (maximal instantaneous gradient at follow-up, 55 +/- 17 vs 79 +/- 22 mm Hg before dilation, p < 0.001). Aortic valve replacements were performed in 5 patients, 2 with unsuccessful initial dilations. At the time of the most recent echocardiogram, 8 of 16 patients remained "incident free," with no subsequent catheterization or surgical interventions, a maximal instantaneous gradient of < or = 55 mm Hg, no more than moderate aortic regurgitation, and preserved ventricular function.(ABSTRACT TRUNCATED AT 250 WORDS)

Severe congenital mitral stenosis in infants.

BACKGROUND: Despite current medical and surgical therapy, infants with symptomatic congenital mitral stenosis (CMS) continue to have high rates of morbidity and mortality. Catheter balloon dilation has been successful in relieving symptoms in a few older children with CMS but has not been evaluated in infants. METHODS AND RESULTS: We reviewed the records of 85 infants with CMS to assess severity of CMS, associated cardiac lesions, echocardiographic morphological appearance of the mitral valve, treatment, and outcome. There were five valve morphologies identified: "typical" hypoplastic mitral valve with symmetric papillary muscles (SYMM, 52%), supravalvar mitral ring (SVMR, 20%), double-orifice mitral valve (DOMV, 11%), hypoplastic mitral valve with asymmetric papillary muscles (ASYMM, 8%), and parachute mitral valve (PARA, 8%). Of the 85 infants, 31 (36%) were severely symptomatic, requiring intervention within the first 2 years. Balloon dilation was performed in 18 infants (age, 8.7 +/- 5.7 months; weight, 5.9 +/- 1.9 kg) and valve surgery in 13 (age, 10.9 +/- 5.9 months; weight, 6.7 +/- 2.1 kg). Balloon dilation decreased the peak transmitral gradient (LAa-LVED) > 30% in 15 of 18 initial attempts, from 20.3 +/- 8.2 to 10.9 +/- 4.9 mm Hg (P < .001), and the mitral valve area increased from 0.7 +/- 0.3 to 1.0 +/- 0.5 cm2/M2 (n = 10, P = .01). No infants died during the initial balloon dilation, although 2 of 3 died during a repeat procedure for restenosis. Other complications included significant mitral regurgitation in 7 of 18 patients (39%), 4 of whom had SVMR. Of the 18 infants, 8 (44%) had persistent symptomatic improvement at a mean follow-up of 14 months (range, 2 to 32 months). The 2-year survival after balloon dilation was 70%; 40% remained free of repeat intervention. Mitral valve surgery in 13 infants consisted of SVMR resections in 7, mitral valve replacements in 4, and LA-to-LV aortic valved homografts in 2. The operative mortality was 30%. Sustained improvement occurred in 8 (6 with SVMR) at 11 to 62 months of follow-up (mean, 30 months), with a 2-year survival of 60%. CONCLUSIONS: Infants with severe CMS have 2-year mortality rates approaching 40% regardless of treatment modality. Balloon dilation significantly reduces the transmitral gradient in the majority, but symptomatic improvement persists in only 40%. Procedure-related mortality was associated with repeat balloon dilation in patients with left ventricular hypoplasia. Balloon dilation of "typical" CMS can provide symptomatic relief in many infants, allowing postponement of valve replacement, although infants with SVMR do better with surgical management.

Traumatic aortopulmonary window as a complication of pulmonary artery balloon angioplasty: transcatheter occlusion with a covered stent. A case report.

We describe a case in which pulmonary artery balloon angioplasty was complicated by formation of an aortopulmonary window, a previously unreported complication associated with this technique. A novel transcatheter approach for occluding the defect, a covered stent, was utilized. Deployment of the covered stent significantly reduced the shunt, allowed for clinical stabilization, and averted the need for emergency surgical intervention.