Differential pulmonary flow in hypoplastic left heart syndrome.

We report a case of hypoplastic left heart syndrome associated with restrictive interatrial communication and partial anomalous pulmonary venous connection via a right lower pulmonary vein draining to the inferior vena cava. We found unequal pulmonary artery pressure and different pulmonary artery structure, with the right pulmonary artery being lower in pressure and more tortuous and dilated in its peripheral branches than the left. This was attributed to the variant degrees of pulmonary venous obstruction. The left pulmonary venous return was severely obstructed by the restrictive interatrial communication, whereas the anomalous right lower pulmonary vein drained into the inferior vena cava, with less obstruction. To the best of our knowledge, there has never before been a report of differential pulmonary flow associated with a partial anomalous pulmonary vein, in a case of hypoplastic left heart syndrome.     

Interatrial conduction (activation) times.

Left atrial electrograms were recorded simultaneously from sites located in the coronary sinus, right pulmonary artery and esophagus in order to determine and correlate the interatrial conduction times obtained from these locations. Ten patients with normal-sized atria and 16 patients with isolated left atrial enlargement were studied. A high correlation existed between the P wave duration and the interatrial conduction times obtained from the coronary sinus and pulmonary artery; good correlations were also found for the interatrial conduction times recorded from the pulmonary artery and esophagus correlated well with those recorded from the distal coronary sinus (the generally accepted standard for the indirect interatrial conduction time measurements). In addition to providing information on the mechanism of atrial arrhythmias, the electrograms obtained from the various indirect left atrial recording sites provide satisfactory quantification of interatrial conduction.     

Anomalous left superior pulmonary venous connection with intact interatrial septum

Partial anomalous pulmonary venous connection (PAPVC) with intact interatrial septum is an uncommon congenital anomaly, while isolated left pulmonary venous connection with intact interatrial septum is rare. In this report, a 5-year-old girl with chief complains of mild short breath after exercise was diagnosed of anomalous connection between left superior pulmonary vein (LSPV) and left innominate vein by transthoracic echocardiography (TTE) that was confirmed by 3D cardiac CT scanning.     

Left-to-right shunt via the foramen ovale in the early neonatal period: evaluation by Doppler color flow mapping

Serial two-dimensional Doppler echocardiography was performed in 22 normal neonates (2-9 hours after birth). A left-to-right shunt through the foramen ovale and a shunt through the ductus arteriosus were evaluated. Interatrial shunts were observed as transseptal jets in 16 of 22 neonates on initial examination and resolved nine to 26 hours after birth in 13 neonates. In the remaining three neonates the shunts were observed more than six days and resolved by two months of age. Shunts through the ductus arteriosus were observed in all neonates examined as diastolic or continuous flows toward the transducer in the main pulmonary artery at the initial examination. The ductal flow resolved simultaneously with (3/13) or after (10/13) the disappearance of interatrial flow. With two-dimensional echocardiography, the enlarged left atrium and rightward deviation of the interatrial septum were observed in the neonates with interatrial shunts. This was confirmed by the immobile septum primum and the increased ratio of the left atrial to aortic diameters (LA/Ao ratio) on the M-mode echo. The interatrial septum became mobile and the LA/Ao ratio decreased after disappearance of the interatrial shunts. It was speculated that in neonates with large ductal shunts, large pulmonary venous flow enters into the less compliant left ventricle and raises the left ventricular end-diastolic pressure. Then, increased left atrial pressure distends the interatrial septum and causes left-to-right interatrial shunts via the stretched foramen ovale. This shunt is considered one of the physiological phenomena occurring in the early neonatal period.     

Electrocardiographic left atrial enlargement electrophysiologic, echocardiographic and hemodynamic correlates

The mechanism of the electrocardiographic pattern termed left atrial enlargement was evaluated in 21 patients. Left atrial size and pressure as well as interatrial conduction were correlated with electrocardiographic left atrial enlargement using echocardiography, mean pulmonary capillary wedge pressure and activation time from the P wave to the coronary sinus. In the group as a whole only prolongation of interatrial conduction time was consistently related to the electrocardiographic pattern of left atrial enlargement; left atrial size or pressure was not predictably abnormal in patients with this pattern. Five patients had neither elevation of pulmonary capillary wedge pressure nor echocardiographic evidence of an enlarged left atrium. When the etiologic type of heart disease was analyzed, an enlarged left atrium correlated with electrocardiographic left atrial enlargement only in patients with rheumatic mitral valve disease (eight of nine patients). Elevated pulmonary capillary wedge pressure correlated with electrocardiographic left atrial enlargement in all four patients with cardiomyopathy. In patients with coronary artery disease the electrocardiographic pattern was unrelated to either left atrial pressure or volume overload. Thus, the electrocardiographic pattern termed left atrial enlargement appears to represent an interatrial conduction defect that can be produced by a variety of factors.     

Initial transcatheter palliation of hypoplastic left heart syndrome.

Initial percutaneous transcatheter palliation of hypoplastic left heart syndrome is now feasible. The primary procedures for palliation include stenting of the ductus arteriosus with a self expanding nitinol stent to secure an adequate systemic blood flow, placement of an internal pulmonary arterial band to protect the pulmonary vascular bed and to prevent pulmonary overcirculation, and widening of the interatrial communication by blade and balloon septostomy or static balloon dilation to decompress the left atrium. Anatomic variations of the ductus arteriosus have important implications for technical success with ductal stenting. Patients who have undergone complete transcatheter palliation with the internal pulmonary band appear to have less immediate morbidity at the time of transplant, with preserved integrity and growth of the branch pulmonary arteries at one year follow-up.     

Retrograde pulmonary vein wedge angiography: A new technique

A new technique of pulmonary vein wedge angiography to delineate pulmonary artery anatomy is described. Conventional pulmonary vein wedge angiography requires an interatrial communication—natural or created by a transseptal puncture. In retrograde pulmonary vein wedge angiography, the left atrium and pulmonary veins are entered from arterial route using a specially designed catheter. This technique can be specially utilized for patients in whom there is no interatrial communication.     

Hemodynamic assessment after palliative surgery for hypoplastic left heart syndrome

Ten patients with hypoplastic left heart syndrome underwent cardiac catheterization to assess the effectiveness of palliative surgery designed to prepare them for a modified Fontan procedure. The objectives of palliation were to establish unobstructed systemic blood flow, normalize pulmonary blood flow and pressure, and relieve pulmonary venous obstruction. In the first four patients, systemic blood flow from the right ventricle was established by means of a conduit from either the right ventricular free wall or the proximal main pulmonary artery to the thoracic aorta. Pulmonary blood flow was limited by pulmonary artery banding and ligation of the ductus arteriosus in three patients and by a Blalock-Taussig shunt in one. Conduit obstruction of systemic blood flow developed in two of these infants, and pulmonary vascular abnormalities precluded reparative surgery in the other two. In the other six patients, systemic blood flow was established by direct anastomosis of the proximal main pulmonary artery to the ascending aorta and aortic arch. The pulmonary vasculature was protected by providing pulmonary flow through a central or Blalock-Taussig shunt. The interatrial communication was enlarged by atrial septectomy or balloon atrial septotomy. One infant had progressive tricuspid regurgitation necessitating valve replacement. One, in whom balloon atrial septotomy had been performed, developed an obstructive interatrial communication necessitating late atrial septectomy. These six patients were candidates for physiologic correction. To date, three patients have undergone a modified Fontan procedure; two are clinically well at 9 and 12 months after surgery. Three patients await this procedure.     

Acute coronary syndrome of paradoxical origin

We describe a rare case of acute myocardial infarction secondary to paradoxical embolism complicating acute pulmonary embolism. A 44-year-old woman presented to the emergency department with chest pain. The physical examination was unremarkable except for oxygen saturation of 75%, and the electrocardiogram showed ST-segment elevation in the inferior leads. Urgent coronary angiography showed a distal occlusion of the right coronary artery and multiple thrombi were aspirated. Despite relief of chest pain and electrocardiogram normalization, her oxygen saturation remained low (90%) with high-flow oxygen by mask. The transthoracic echocardiogram showed a mass in the left atrium and dilatation of the right chambers, while the transesophageal echocardiogram showed a thrombus attached to the interatrial septum in the region of the foramen ovale. Color flow imaging was consistent with a patent foramen ovale. Thoracic computed tomography angiography documented thrombi in both branches of the pulmonary trunk. After five days on anticoagulation, the patient underwent surgical foramen ovale closure.     

Divided left atrium associated with supravalvar mitral ring.

Reported is a case with a rare association of divided left atrium, supramitral stenosing ring of the left atrium, connection of the left superior caval vein to the roof of the left atrium, unroofed coronary sinus with an interatrial communication at the mouth of the unroofed sinus and ventricular septal defect. The need for a complete echocardiographic examination in the presence of pulmonary venous obstruction is emphasized. Surgery was successful in spite of significant preoperative pulmonary hypertension.     

Cyanosis in patients with atrial septal defect due to systemic venous drainage into the left atrium

Cyanosis and clubbing of the digits in patients with atrial septal defect usually are indicative of reversal of the interatrial shunt consequent to reduced right ventricular compliance and severe pulmonary hypertension. The condition may be considered inoperable. The cases reported herein emphasize the occurrence of cyanosis in patients with interatrial communication and continued significant left to right shunting, as a consequence of systemic venoarterial shunting into the left atrium. Carefully planned cardiac catherization is indicated to detect the less well recognized mechanisms of cyanosis so that such patients are not denied the benefits of surgical closure of the septal defect.     

Echocardiographic analysis of interatrial septal motion.

Interatrial septal motion was analyzed in 12 normal subjects and 19 patients with right or left atrial overloading using a new method for recording echograms of the mid portion of the interatrial septum through each cardiac cycle. In normal subjects, septal motion was characterized by eight distinct points that were identified and designated on the septal echogram. The septum showed gradual anterior motion (toward the right atrium) in mid and end systole and in early diastole. After reaching the most anterior point, it moved posteriorly (toward the left atrium). During mid diastole it showed very little motion. After the P wave of electrocardiogram it showed slight posterior and then anterior motion.In all eight patients with mitral stenosis, the motion of the interatrial septum was diminished. In all seven patients with mitral regurgitation due to chordal rupture, the septal motion was increased. Systolic fluttering of the septum was observed in four of seven patients. In two patients with Ebstein's anomaly, paradoxical motion of the interatrial septum (posterior motion in systole) was observed. In two patients with primary pulmonary hypertension, septal motion was very much decreased. Interatrial septal motion was thought to result from the interatrial pressure gradient through each cardiac cycle. This method of recording the motion of the interatrial septum seems to be useful for diagnosing right or left atrial overloading and for studying hemodynamic events in both atria.     

Sudden transformation of pulmonary stenosis to trilogy of Fallot in a 65 year old patient

The authors report the case of a 64 year old woman with typical valvular pulmonary stenosis in whom spontaneous and sudden reopening of the foramen ovale resulted in cyanosis. Transthoracic echocardiography with injection of contrast provides a complete diagnosis: valvular pulmonary stenosis with a mean pressure gradient of 83 mmHg and massive right-to-left interatrial shunt. The malformation was treated by interventional catheterisation in a two-stage procedure: pulmonary valvuloplasty followed by closure of the foramen ovale because of the persistence of a right-to-left interatrial shunt. The functional improvement was followed by the appearance of effort angina. Coronary angiography showed single vessel disease of the left anterior descending artery treated by stenting. The long-term outcome was satisfactory.     

Dramatic decrease in the pulmonary artery systolic pressure and disappearance of the interatrial shunt with sildenafil treatment in a patient with primary pulmonary hypertension with atrial septal aneurysm and a severe right to left shunt through the patent foramen ovale

This report describes a patients with PPH with atrial septal aneurysm and a severe right to left shunt through the patent foramen ovale who showed a dramatic decrease in the pulmonary artery systolic pressure and interatrial shunt disappeared after sildenafil treatment.     

Correction of anomalous drainage of right superior vena cava to left atrium

A 2-year-old boy with cyanosis was found to have normal situs and looping with anomalous drainage of a right-sided superior vena cava to the left atrium, and intact interatrial septum in association with anomalous drainage of the left pulmonary veins to the right superior vena cava. He underwent successful surgical repair of this rare congenital malformation.     

Diagnosis of paradoxal and concomitant pulmonary thromboembolism with transesophageal echocardiography: a clinical case]

There is some controversy regarding the indications for transesophageal echocardiography in patients with suspected systemic embolism. The present case report refers to a 65 year old male admitted to the hospital for ischemic acute cerebrovascular accident, which was confirmed by cerebral computerized tomography. A transthoracic echocardiogram was performed showing right atrial and ventricular dilatation. A transesophageal echocardiogram was also performed to exclude thromboembolism and clarify dilatation of the right cavities. Mild spontaneous echocontrast was present in the left atrium without images of thrombus; an interatrial septal aneurysm with patent foramen ovale was found with right to left flow; an image compatible with a very mobile, large, proximal thrombus in the main pulmonary artery was observed. A venous duplex scan was performed, demonstrating venous thrombosis in the right popliteal and femoral veins. Pulmonary arteriography showed a large thrombus in the right pulmonary branch extending to the median lobe and a smaller thrombus in the left pulmonary branch. Apparently, the patient had no predisposing factors for thromboembolism. Full-dose heparin was started followed by oral anticoagulation. An inferior vena cava filter was implanted. At hospital discharge the pulmonary thrombus had disappeared and the right cardiac cavities had returned to normal size. The interatrial aneurysm had disappeared and foramen ovale was no longer patent. After 36 months of clinical follow up on oral anticoagulation, the patient remains asymptomatic without neurological sequelae nor respiratory distress.     

Operative timing for absent pulmonary valve with obstructive sleep apnea

Congenital absence of the pulmonary valve appears to have a prolonged fate, despite substantial regurgitation, thus the optimal timing of surgical correction remains unclear. A 53-year-old man with isolated pulmonary regurgitation accompanied by obstructive sleep apnea developed progressive heart failure after reopening of the foramen ovale. Closure of the interatrial shunt and pulmonary valve replacement with a 25-mm mechanical prosthesis relieved his refractory left heart failure.     

Clinical use of blade atrial septostomy

A cardiac catheter enclosing an extensible blade was used to enlarge the interatrial opening in seven patients. Two patients with transposition of the great arteries who had balloon atrial septostomy as newborns subsequently presented with clinical evidence of a restrictive interatrial opening at 1 and 4 months of age. Cardiac catheterization confirmed restenosis of the interatrial opening and inadequate intracardiac mixing. After blade atrial septostomy the systemic arterial oxygen saturation increased by 20% and 30%, respectively. Five patients with mitral atresia complex, ages 2 months-9 1/2 years, had a restrictive interatrial communication and severe pulmonary venous hypertension (mean left atrial pressures ranged from 20-38 mm Hg). Following blade atrial septostomy, the pressure gradient between the atria was almost completely abolished and prompt clinical improvement was observed in each patient. All patients tolerated the procedure without complications. Blade atrial septostomy was a safe, effective procedure for enlarging the interatrial communication in this limited series of patients with an interatrial septum too thick to permit adequate rupture by conventional balloon atrial septostomy.     

Percutaneous mitral commissurotomy in a case of mirror-image dextrocardia and rheumatic mitral stenosis

A 43-year-old male with mirror-image dextrocardia and severe rheumatic mitral stenosis was subjected to successful percutaneous transvenous mitral commissurotomy (PTMC). The standard Inoue technique was modified by transseptal catheterization via the left femoral vein, image inversion, delineation of the interatrial septal anatomy via levophase pulmonary angiography, septal contrast staining and pigtail catheter insertion in the noncoronary aortic sinus, interatrial septal puncture with the transseptal needle rotated to a 7 o'clock position and left ventricular entry with a reverse loop technique. There were no procedural complications. Intracardiac pressures and mitral valvular planimetry suggested a successful procedural outcome. This case illustrates that PTMC can be accomplished safely in patients with this unusual cardiac anatomy with a few modifications in the standard technique.     

Lutembacher's syndrome and a new concept of the dynamics of interatrial septal defect

A report of a case of Lutembacher's syndrome (combination of interatrial septal defect and mitral stenosis) is presented. The currently held view of the dynamic changes in such a heart is discussed. It is pointed out that the fundamental disturbance in dynamics is the same whether or not the septal patency is complicated by a mitral lesion. According to previous investigators, the ultimate development of marked dilatation and hypertrophy of the right auricle and right ventricle, with minor involvement of the left auricle and left ventricle, is caused by shunting of blood through the communication, which in turn results from the fact that the pressure in the left auricle is higher than that in the right. Evidence is presented to show that this explanation is not tenable.A new concept of the dynamics of interatrial septal defect, based on a correlation between fundamental hydraulic principles and anatomic and experimental considerations, is proposed. It is shown that when two adjoining chambers have a source of constant and equal inflow, a free communication in their common wall, and outflow orifices of equal diameter, the gravitational orientation of the chambers determines their respective sizes, intraluminal pressures, and volume flows. If the chambers are placed one above the other, with the communication in a horizontal plane, the inferior chamber dilates and its outflow trajectory extends beyond that of the upper chamber, which indicates that there is a greater intraluminal pressure in the lowermost chamber.From an anatomic standpoint, evidence is presented to show that the auricular axis is such that the left auricle occupies a definitely more cephalad position that the right. Further, the plane of the foramen ovale (septal defect) is almost horizontal, and not vertical, as it is commonly represented. With the disposition of the chambers and septal defect in this relationship, filling of the right auricle is accomplished by the usual caval flow, and by a gravitational flow through the communication in the floor of the superiorly placed left auricle. Dilatation of the right auricle results, and, in due time, the right side of the heart shows dilatation and hypertrophy, whereas the left auricle and ventricle, which play almost no role in these events, remain essentially unaffected. The aorta becomes hypoplastic because of the decreased systemic volume of blood. The pulmonary arterial tree, on the other hand, necessarily dilates to accommodate the increased volume of blood in the lesser circuit. The presence of mitral stenosis simply exaggerates the flow differences.The proposed concept obviates the necessity of postulating a pressure gradient theory to explain the pathologic changes, and offers, instead, a well-correlated explanation of the entire progression of events which are associated with an interatrial septal defect.