New trends in the management of congenital heart disease

Considerable improvements have been made in the diagnosis and treatment of congenital heart disease during the last decade. Many congenital heart lesions are now treated successfully during the neonatal period that previously were associated with high mortality. Improved echocardiographic imaging, catheterization techniques, and earlier surgical repair are factors that have resulted in greater success in the treatment of congenital cardiac disease. Diagnosis has been improved greatly with advancements in echocardiography and angiography. Better ultrasound technology combined with doppler techniques and transesophageal echocardiography allow more accurate preoperative assessment and therefore more successful surgical repair. Cardiac catheterization techniques have also improved and, when combined with treatment such as balloon angioplasty, have changed the treatment of certain cardiac anomalies such as pulmonary stenosis or coarctation of the aorta. Operative treatment of congenital heart disease has improved the short- and long-term survival of most infants with congenital cardiac anomalies. Improved cardiopulmonary bypass techniques, better suture material, and the ability to perform cardiac transplantation are examples of technology that allows earlier, more complete repair of these complex cardiac defects. Reviewed here are improvements in the treatment of four complex cardiac anomalies that occur in newborns and are associated with high mortality when left untreated. All four anomalies have undergone significant changes in the approach to their treatment with dramatic improvements in survival.     

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.     

Anomalous pulmonary venous return in the staged palliation of functional univentricular heart defects

BACKGROUND: Bidirectional cavopulmonary shunt and Fontan repair are now commonly performed in patients with a variety of forms of complex single ventricle, including those with anomalies of systemic, pulmonary, or systemic and pulmonary venous return. These anomalies are ideally dealt with during bidirectional cavopulmonary shunt, thereby minimizing the complexity of the eventual Fontan procedure. METHODS AND RESULTS: Between March 1990 and March 1997, 32 patients with functional single ventricle and anomalous pulmonary venous return underwent operation at our institution. Five of 25 patients who underwent neonatal palliation died in the early postoperative period, all of whom had obstructed anomalous pulmonary venous return. Twenty-one patients have undergone bidirectional cavopulmonary shunt, including 7 in whom this was the primary palliative procedure. There was one early and two late deaths after the bidirectional Glenn procedure, two in patients with asplenia syndrome and none in patients with previously obstructed pulmonary venous return. Seven patients have undergone Fontan completion, 5 with an extracardiac conduit. There was one early death and one take-down to a classic Glenn shunt, both in patients who did not undergo the extracardiac conduit Fontan operation. CONCLUSIONS: Anomalous pulmonary venous return can significantly complicate the management of the single-ventricle patient, with the major impact on survival coming in the neonatal period. Palliation with the aim of performing an extracardiac conduit Fontan procedure allows greater latitude and more streamlined management in this group of patients.     

Surgical treatment of a fistula between the right pulmonary artery and the left atrium: presentation of two cases and review of literature

OBJECTIVE: A direct communication between the pulmonary artery and the left atrium is a rare anomaly. On the basis of two cases of our own and a literature review of 49 cases, we focus on clinical presentation, anatomy, diagnosis, and the role of surgery. METHODS: Two cases of a fistula between the right pulmonary artery and the left atrium are described in a girl of 4 years and a boy of 15 years. Both presented with unexplained cyanosis. Diagnosis was made on echocardiography and angiography. The fistula was ligated using extracorporeal circulation in the first case and not in the second case. RESULTS: The surgical results were successful with resolution of the cyanosis. CONCLUSIONS: In newborns, urgent surgery may be necessary. In other patients, early elective surgical correction should be performed to prevent complications, especially systemic and cerebral emboli, cerebral abscesses, and rupture of aneurysmal fistulas. Complete cure can be achieved by ligation and possible division or by intracardiac repair.     

Atrioventricular valve dysfunction: evaluation by Doppler and cross-sectional ultrasound

BACKGROUND: A variety of factors can influence the suitability of a congenitally malformed heart for biventricular repair, including size, morphology, function, and dimensions and function of the inflow and outflow, among others. Although certain features have been identified that may indicate a lower probability of successful biventricular repair, our ability to predict whether a particular patient will be able to tolerate completely separate in-series systemic and pulmonary circulations remains imperfect. METHODS AND RESULTS: In this review, we discuss the echocardiographic evaluation of various factors that can influence a patient's suitability for two ventricle repair. We call on our own experience, and illustrate our discussion with a number of echocardiographic images. CONCLUSIONS: In most cases, echocardiography allows for full assessment of the anatomic and functional features that influence whether a patient is a suitable candidate for biventricular repair. Although a number of indices have been developed for determining who can and cannot be expected to undergo successful two ventricle repair, there remains substantial room for progress in this area.     

What are the possible causes of neonatal nephrocalcinosis?

The development of pulmonary arteriovenous fistulas after bidirectional cavopulmonary operations, such as the bidirectional Glenn shunt and Kawashima's procedure, has raised concern. Development of these fistulas, which are more frequent than initially thought, can represent a limiting factor in the late outcome of these patients and may even limit the indication for these types of surgery. Whether the fistulas can be reversed by transforming the surgical procedures has yet to be established. In the hope of avoiding this kind of complication, thought to be caused by the lack of passage of a hypothetical hepatic factor through the pulmonary circulation, we have developed an inverted type of bidirectional cavopulmonary connection in which the blood coming from the liver perfuses immediately both lungs. This is made possible by shunting via an intra-atrial tunnel the blood from the superior caval vein directly to the left atrium, and the blood from the inferior caval vein to the right branch of the pulmonary trunk (keeping its bifurcation intact). We describe findings in two patients undergoing successful surgery with this technique. Serial follow-up with contrast echocardiography did not show evidence of arteriovenous pulmonary fistulas. Despite our numbers being small, and the time of follow-up being limited, we believe that it is important to document these and similar cases.     

The role of intraoperative echocardiography in valve surgery

The widespread use and popularity of intraoperative echocardiography (IOE) has resulted from advances in cardiac surgery, reparative procedures for valvular heart disease and, most specifically, mitral valve repair. IOE has grown exponentially and is becoming an integral part of the planning and evaluation of many types of surgical procedures such that it is now considered standard of care especially for the perioperative management of patients undergoing mitral and aortic valve repair. This article discusses the application of intraoperative echocardiography and focus specifically on valvular heart disease as this represents the most widely accepted indication for the procedure in current clinical practice.     

The operability of patient with pulmonary hypertension judged from hemodynamic changes before and after surgery

1) In congenital heart disease with pulmonary hypertension, the place for surgical correction still remains even with almost systemic PA pressure if R to L shunt ratio on lung scintigram is lower than 25%. 2) The patient with pulmonary hypertension in congenital heart disease younger than 3 years of age has wider acceptability for surgery compared to older patient. 3) In patients with mitral valvular disease, surgical correction seems to be indicated irrespective of PA pressure, if their preoperative U/L are lower than 2.4.     

Laparoscopically assisted abdominal aortic aneurysm repair: first 20 cases

PURPOSE: Laparoscopic surgery decreases postoperative pain, shortens hospital stay, and returns patients to full functional status more quickly than open surgery for a variety of surgical procedures. This study was undertaken to evaluate laparoscopic techniques for application to abdominal aortic aneurysm (AAA) repair. METHODS: Twenty patients who had AAAs that required a tube graft underwent laparoscopically assisted AAA repair. The procedure consisted of transperitoneal laparoscopic dissection of the aneurysm neck and iliac vessels. A standard endoaneurysmorrhaphy was then performed through a minilaparotomy using the port sites for the aortic and iliac clamps. Data included operative times, duration of nasogastric suction, intensive care unit days, and postoperative hospital days. Pulmonary artery catheters and transesophageal echocardiography were used in seven patients. For these patients data included heart rate, pulmonary artery systolic and diastolic pressures, mean arterial pressure, central venous pressure, pulmonary capillary wedge pressure, cardiac index, and end diastolic area. Data were obtained before induction, during and after insufflation, during aortic cross-clamp, and at the end of the procedure. RESULTS: Laparoscopically assisted AAA repair was completed in 18 of 20 patients. Laparoscopic and total operative times were 1.44 +/- 0.44 and 4.1 +/- 0.92 hours, respectively. Duration of nasogastric suction was 1.3 +/- 0.7 days. Intensive care unit stay was 2.2 +/- 0.9 days. The mean length of hospital stay was 5.8 days excluding three patients who underwent other procedures. There were two minor complications, one major complication (colectomy after colon ischemia), and no deaths. For the eight patients who had intraoperative transesophageal echocardiographic monitoring, no changes were noted in heart rate, pulmonary artery systolic pressure, pulmonary capillary wedge pressure, and cardiac index. Pulmonary artery diastolic pressure and central venous pressure were greatest during insufflation without changes in end-diastolic area. Volume status, as reflected by end-diastolic area and pulmonary capillary wedge pressure, did not change. CONCLUSIONS: Laparoscopically assisted AAA repair is technically challenging but feasible. Potential advantages may be early removal of nasogastric suction, shorter intensive care unit and hospital stays, and prompt return to full functional status. The hemodynamic data obtained from the pulmonary artery catheter and transesophageal echocardiogram during pneumoperitoneum suggest that transesophageal echocardiography may be sufficient for evaluation of volume status along with the added benefit of detection of regional wall motion abnormalities and aortic insufficiency. Further refinement in technique and instrumentation will make total laparoscopic AAA repair a reality.     

Minimally invasive diaphragm plication in an infant

We report the use of video-assisted thoracic surgery to plicate the diaphragm after phrenic nerve injury associated with an operation for congenital heart disease. Right diaphragm paresis developed in a cyanotic newborn girl with pulmonary atresia and intact ventricular septum after a right modified Blalock-Taussig shunt. Diaphragm plication was performed endoscopically and the patient recovered. Refinement of technique and instrumentation may allow wider application of video-assisted thoracoscopic plication of the diaphragm in neonatal and pediatric patients.     

Intraoperative epicardial echography in infancy and childhood for the evaluation of the results of surgical correction of congenital heart defects

Intraoperative epicardial echocardiography (IEE) is very useful to assess the result of the surgical procedure. In infancy and childhood the authors performed 32 IEE (using high frequency transducer) out of 193 operations with congenital heart diseases. As a result of IEE study the surgical procedure was extended in 5 cases, as follows: closure of patent ductus arteriosus, exchange of transanular patch, repeated mitral repair, prosthetic mitral valve implantation, and correction of residual right to left shunt. No early or late reoperation was necessary in the remaining cases. Follow up echocardiography and autopsy in 4 cases confirmed the diagnosis of the IEE. The results suggest, that IEE will be the standard method for quality control of surgical procedures in congenital heart disease.     

The clamshell approach for the surgical treatment of complex cardiopulmonary pathology in infants and children

BACKGROUND: The surgical approach to children with complex cardiovascular and pulmonary anomalies is still controversial. Staged operations through multiple incisions are often performed in this setting. OBJECTIVE: The different applications and clinical advantages of a bilateral thoracosternotomy approach to complex cardiothoracic disease requiring surgical repair were reviewed retrospectively. METHODS: Between January 1993 and June 1995, 33 patients, aged between 2 months and 17 years (mean 7.8 +/- 5.3) underwent surgical treatment of complex cardiovascular or pulmonary disease using a clamshell approach. Twenty-one patients (64%) had undergone 1-5 previous surgical procedures (mean 2.5 +/- 1.0/patient). The technique involved supine position placement, submammary incision, access to the pleural space bilaterally through the fourth intercostal space and transverse division of the sternal body. RESULTS: Four groups of patients were operated on via this approach: (1) patients undergoing lobar, lung or heart-lung transplantation (40%); (2) patients undergoing repair of tetralogy of Fallot/pulmonary atresia (36%); (3) patients with previously corrected miscellaneous procedures (12%), including completion of Fontan, one-stage repair of left main bronchial stenosis and atrial septal defect, one-stage repair of partial anomalous pulmonary venous connection and aortic coarctation, and repair of congenital pulmonary venous stenosis. There were two early (< 30 days) deaths, giving a perioperative mortality of 6% for the entire series. Complications included postoperative hemorrhage in 4 patients (12%), prolonged ventilation time due to mechanical failure in 4 (12%). There were no wound infections. Analysis of complications by group showed the lung transplant group to be more affected (18% of patients experienced complications). Except for 2 infants undergoing complete unifocalization and presently awaiting completion of repair of tetralogy of Fallot/pulmonary atresia, in the remaining 31 (94%) a definitive surgical treatment could be performed in one-stage. CONCLUSIONS: The bilateral thoracosternotomy allows optimal exposure of all intrathoracic anatomic structures making one-stage surgical repair possible in a variety of complex cardiovascular and pulmonary anomalies. Early mortality and technique-related morbidity do not differ from those reported with the conventional approaches to the different disease conditions. A wider application of the clamshell approach for the management of complex intrathoracic pathology in infants and children is advocated.     

Pulmonary artery banding with a novel percutaneously, bidirectionally adjustable device

Pulmonary artery banding is commonly performed as a palliative procedure in complex congenital heart disease, when pulmonary blood flow is increased. However, the hemodynamics may change postoperatively requiring readjustment of the band, which may necessitate a second operation. We report a new system for pulmonary artery banding which allows precise placement of the band intraoperatively, as well as bidirectional percutaneous adjustment of the band postoperatively. Via left lateral thoracothomy the new device was implanted without complications into a neonate with congestive heart failure due to tricuspid atresia (IIc) and coarctation of the aorta. Although optimal placement of the band had been achieved intraoperatively the band had to be tightened 25 h after the operation and released 85 h after the operation in order to optimize hemodynamics. The bidirectionally adjustable device for banding of the pulmonary artery is superior to previously used devices with either no or unidirectional adjustability of the band because it is safe and easy to implant and has the potential to reduce the number of reoperations associated with this type of procedure.     

Controllable graded cerebral ischaemia in the gerbil: studies of cerebral blood flow and energy metabolism by hydrogen clearance and 31P NMR spectroscopy

Patent ductus arteriosus is an uncommon anomaly in adult patients. Surgical closure of patent ductus arteriosus in this age group presents difficult problems to the surgeon. We report our experience of 21 adult patients (19-62 years of age, mean 40 years) who underwent closure of the ductus by transfemoral implantation of a Rashkind double umbrella device. The patients came to light because of atrial fibrillation, congestive heart failure, residual flow after surgical ligation of the duct or because of incidental diagnosis made during physical examination or chest X-ray. In ten patients the pulmonary arterial pressure was normal (systolic pressure < 30 mmHg), in eleven it was elevated (systolic pressure from 30 to 100 mmHg, mean 50 mmHg). In seven patients the duct was clearly calcified and the size of the duct varied from 3 to 9 mm (mean 4.3 mm). In 16 patients the ductus resulted perfectly closed after implantation of the first double umbrella device, two patients had minimal residual aortopulmonary flow, whereas in three patients the residual shunt was significant; two of these also developed haemolysis and went to surgery, in the latter the shunt was completely abolished after implantation of a second 17-mm device 16 months later. In conclusion transcatheter closure of patent ductus arteriosus in adults is feasible, even in the presence of calcifications and/or pulmonary hypertension; taking into account the significant surgical risk, PDA umbrella closure should be considered the first choice procedure in this group of patients.     

Bidirectional cavopulmonary shunt in patients with anomalies of systemic and pulmonary venous drainage

BACKGROUND: Bidirectional cavopulmonary shunt and Fontan repair are now commonly performed in patients with a variety of forms of complex single ventricle, including those with anomalies of systemic or pulmonary venous return. These anomalies are ideally dealt with during bidirectional cavopulmonary shunt, thereby minimizing the complexity of the eventual Fontan procedure. METHODS: Between March 1990 and December 1995, 36 patients with anomalous systemic or pulmonary venous drainage underwent bidirectional cavopulmonary shunt. A combination of anomalous systemic and pulmonary venous drainage was present in 12 patients, whereas 19 patients had anomalous drainage only from the systemic circulation and 5 patients had isolated anomalies of pulmonary venous return. Visceral heterotaxy syndrome was diagnosed in 18 patients. The median age at operation was 11 months, and bidirectional cavopulmonary shunt was the first surgical procedure performed in 10 of these patients. Techniques of repair are described. RESULTS: There were two early deaths and one bidirectional cavopulmonary shunt was taken down, for mortality and failure rates not significantly different than those for all patients undergoing bidirectional cavopulmonary shunt during this time period (n = 117). At a mean follow-up of 19.9 months, there have been three late deaths and 11 patients have undergone Fontan completion. Actuarial survival was 87% at 1 year and 81% at 3 years. Among all patients undergoing bidirectional cavopulmonary shunt during this time period, neither heterotaxy syndrome nor anomalies of systemic or pulmonary venous return were significantly associated with decreased survival or poor outcome. CONCLUSIONS: Bidirectional cavopulmonary shunt can be performed in patients with anomalous systemic or pulmonary venous drainage, including those with visceral heterotaxy syndrome, with morbidity and mortality rates that do not differ significantly from those achieved in all patients undergoing bidirectional cavopulmonary shunt. In this report, we describe our experience with this group of patients, primarily focusing on outcomes and technical issues that pertain to the use of bidirectional cavopulmonary shunt as a preparatory procedure for the extracardiac conduit Fontan operation.     

Immediate postoperative respiratory complications after coronary surgery

The influence of anesthesia, surgical procedure and special conditions of open-heart surgery upon respiratory function alterations is analyzed. Hypoxemia (present even in non-complicated open heart surgery) can be due to alveolar hypoventilation, ventilation-perfusion mismatch or shunt. The origin of atelectasias (present in 50-92% of patients) and pleural effusion (42-87%) is discussed. Phrenic nerve damage is usually secondary to thermal injury. Other less common complications are discussed. The influence of age, smoking and previous pulmonary diseases on respiratory complications is analyzed. Respiratory care after heart surgery (as time and requisites of extubations) and results of different methods (CPAP, PEEP, incentive inspirometry) are reviewed.     

Cancer: a response to prolonged tissue necrosis

We report the first case published in Spain of a palliative anatomic correction associated with aortic arch repair in a neonate with (S,D,L)-transposition of the great arteries, multiple ventricular septal defects, and severe hypoplasia of the right ventricle with subaortic obstruction and hypoplasic aortic arch with coarctation. A one stage palliative surgery on cardiopulmonary bypass was performed with reconstruction of the aortic arch and an arterial switch procedure which obtained a satisfactory result. The principle of this operation is to switch the subaortic obstruction into a subpulmonary obstruction and reconstruct a large natural aortic root from the principal ventricle. The right ventricle-pulmonary artery continuity may promote growth of the right ventricle with the possibility of a future biventricular repair. We conclude that this operation, when used by surgical teams experienced with arterial switch surgery, is the best treatment for the complex newborn group with single ventricles or severe ventricular disbalance, ventriculoarterial discordance and stablished subaortic stenosis.     

Study of congenital cardiopathies with left-right shunt using gamma-angiocardiography

Red blood cells labelled with radioactive Technetium were injected intravenously, and the passage of the tracer through the cardio-pulmonary system recorded using a scintillation camera coupled with a numerical dosimeter. The results are presented as serial analoque pictures taken at the rate of two per second, as numerical tracings which are later processed, and as flow charts from predetermined areas of interest: the chambers of the heart, the lung parenchyma, and the aorta. This study is concerned with 58 patients with a left-to-right shunt, and about 40 normal examinations were used as a baseline for comparison. In cases of left-to-right shunt, the finding on the tracings is of abnormally prolonged activity in the lungs after a normal passage through the right side. The intensity-duration curves highlight this finding, and show an early recirculation peak in the right side of the heart and a slowing of pulmonary emptying, which can be evaluated numerically from the ratio C2/C1. A correlation has been found between this value and the ratio of pulmonary to systemic flow as calculated by oximetry. The correlation is even closer if a comparison is made between the curves of pulmonary radioactivity and the dye dilution curves. In certain cases, the shunt can be localised to the atrial or ventricular level. There are many indications for this safe investigation: --the diagnosis and monitoring of the flow through a left-to-right shunt in a child; --confirmation of the closure of septal defects after surgery; --clarification of an infudibulo-pulmonary syndrome.     

Cerebral emboli during cardiac surgery in children

BACKGROUND: Microemboli occur commonly during cardiac surgery in adults, and, when present, increase the risk of neuropsychological deficits. Their incidence and significance during correction of congenital heart disease is unknown. The authors hypothesized that microemboli would occur before bypass with right-to-left cardiac shunts and would also occur in large numbers when the aortic crossclamp was released in children during repair of congenital heart defects. METHODS: In 25 children studied with carotid artery Doppler, embolic signals were counted and timed in relation to 13 intraoperative events. Patients were classified as either at high risk (obligate right-to-left shunt or uncorrected transposition of the great arteries) or at low risk (net left-to-right shunt or simple obstructive lesions) for paradoxical (venous to arterial) emboli. RESULTS: The median number of emboli detected was 122 (range, 2-2,664). Forty-two percent of all emboli were detected within 3 min of release of the aortic crossclamp. The high-risk group had significantly more emboli (median, 66; range, 0-116) during the time interval before cardiopulmonary bypass than did the low-risk group (median, 8; range, 0-73), with P < 0.01. There was no significant difference between the high- and low-risk groups in the total number of emboli detected. There was no apparent association between number of emboli and gross neurologic deficits. CONCLUSIONS: Microemboli can be detected in the carotid arteries of children undergoing repair of congenital heart disease and are especially prevalent immediately after release of the aortic crossclamp. The role of emboli in causing neurologic injury in children undergoing repair of congenital heart disease remains to be determined.     

Arterial prosthesis of microporous expanded polytetrafluoroethylene for construction of aorta-pulmonary shunts

A new arterial prosthesis made of polytetrafluoroethylene (OTFE) was evaluated in 10 infants with complex cyanotic congenital heart disease. All grafts used were 4 mm. in diameter and varied in length from 0.8 to 6 cm. The grafts were anastomosed to the main pulmonary artery or its bifurcation in 8 infants and to the right and left pulmonary arteries in one each. There were two early deaths, one of which was related to shunt failure. The advantages of a shunt to the main pulmonary artery are obvious, and the intraoperative procedure is facilitated with the prosthesis. Follow-up averages 9 months in the 8 survivors, and the patients have nearly doubled their preoperative weight. A shunt murmur is present in each case and the children have mild-to-moderate cyanosis at rest. Repeat aortograms in 2 patients, 8 and 10 months postoperatively, show a smooth graft without luminal narrowing. The aortic oxygen saturations were 73 per cent. The PTFE graft and/or anastomoses will not grow with the growth of the child and therefore may not accommodate growth by increased flow. This may prove to be a limiting factor in its long-term use in fants. We reserve the use of these grafts for infants with complex cyanotic defects undergoing emergency surgery or in older children in whom a conventional shunt is not possible or a previous shunt has failed.