Pulmonary artery and left heart end-diastolic pressure relations.

The exponential fall of the pulmonary pressure curve from its systolic peak to left atrial pressure previously described in the presence of normal intraventricular conduction has been investigated in patients with right bundle-branch block. We have been able to show once more that the pulmonary artery diastolic pressure seeks the left atrial level: when right ventricular systole is delayed the pulmonary artery pressure continues to fall with the left atrial 'x' descent.     

Double-outlet left ventricle: Diagnosis and management

Double-outlet left ventricle (DOLV) is a rare congenital cardiac malformation in which both great arteries originate entirely or predominantly from the morphologic left ventricle. DOLV occurs most commonly in the form of atrial situs solitus with atrioventricular (AV) concordance. Ventricular septal defect (VSD) is most commonly subaortic, and 90% of these patients have associated pulmonary stenosis. In most cases, there is a right anterior position of the aorta relative to the pulmonary artery. Most patients with DOLV will have pulmonary outflow obstruction and present soon after birth with cyanosis. DOLV with two well-developed ventricles is conventionally treated surgically by VSD closure, closure of the native left ventricle-to-pulmonary outflow, and placement of a right ventricle-to-pulmonary artery extracardiac conduit. However, pulmonary root translocation may be used as an alternative to biventricular repair of DOLV. Patients with DOLV and functionally single-ventricle or AV valve atresia will require a Fontan procedure.     

Separation of the left atrium from the right pulmonary artery in the suprasternal echocardiogram: a parameter of left atrial pressure

A separation of the left atrium from the right pulmonary artery during atrial contraction may be observed in the suprasternal echocardiogram. In 280 catheterized patients with sinus rhythm, we investigated whether left atrial separation is a parameter from which an estimate of the left atrial pressure can be obtained. In 239 of the 280 patients, the suprasternal echograms were of a quality such that it could be seen whether there was, a left atrial separation. In 182 patients, a normal left atrial pressure (greater than or equal to 12 mm Hg) was found; in 57 patients, the left atrial pressure was elevated. An atrial separation was observed in 183 patients, and in 56 patients it was lacking. Lack of left atrial separation indicates a left atrial pressure elevation with a sensitivity of 73.7% and a specificity of 92.3%. If a left atrial pressure above 18 mm Hg was considered elevated, the sensitivity of this echoparameter amounted to 90.3%, and the specificity was 86.5%. The study shows that the left atrial separation from the right pulmonary artery separation from the right pulmonary artery in the suprasternal echocardiogram is a parameter valuable in providing a rough estimate of the left atrial pressure.     

Partial pressure of oxygen is lower in the left upper pulmonary vein than in the right in adults with atrial septal defect: difference in P(O2) between the right and left pulmonary veins

BACKGROUND: The right-to-left shunt at the atrial level is responsible for arterial hypoxemia in patients with atrial septal defect. OBJECTIVES: This study investigated the mechanism of arterial hypoxemia in patients with atrial septal defect by measuring the P(O2) in both the right and left upper pulmonary veins. SUBJECTS AND METHOD: We prospectively measured the P(O2) in the femoral artery and the right and left upper pulmonary veins during cardiac catheterization in 13 adults (median age, 53 years) and 7 children (median age, 7 years) with secundum atrial septal defect. The adults and children were studied consecutively. Contrast echocardiography was performed to evaluate right-to-left shunt in all adults. RESULTS: Among the children, there were no patients showing arterial hypoxemia, and there was no difference in the P(O2) (+/-SD) between the right and left upper pulmonary veins (right, 100+/-3.8 mm Hg vs left, 100+/-7.8 mm Hg; p = 0.92). However, arterial hypoxemia was present in 11 of the 13 adult patients, although contrast echocardiography showed more than a moderate degree of right-to-left shunt in only four adults. The P(O2) was lower in the left upper pulmonary vein than it was in the right upper pulmonary vein in all adult patients (right, 91.6+/-13.8 mm Hg vs left, 73.0+/-11.5 mm Hg; p < 0.0001). CONCLUSION: The P(O2) was lower in the left upper pulmonary vein than it was in the right upper pulmonary vein in adults with atrial septal defect. Care must be taken in measuring pulmonary blood flow if the P(O2) in the left upper pulmonary vein is low enough to influence oxygen content. The decreased P(O2) in the left upper pulmonary vein may contribute to arterial hypoxemia in addition to right-to-left shunt at the atrial level in adults with atrial septal defect.     

An unusual coronary arteriocameral fistula

A case of a coronary arteriocameral fistula in a 28 year old woman is reported. There was an abnormal coronary artery arising from the main pulmonary artery and connecting with both the left coronary artery and the left atrial appendage. In addition, the pulmonary valve was biscuspid and the mitral valve incompetent. The diagnosis of the communication between the pulmonary artery and the left atrium was made with the aid of right heart catheterization and selective cineangiocardiography. However, the communication between the aorta and the fistula was not demonstrated during life. The patient died suddenly four days after cardiac catheterization. Death was attributed to an arrhythmia four days after the investigation.

The hemodynamic situation and the anatomic findings are discussed. Partial surgical correction would have been possible but may not have influenced the prognosis.     

Isolation of the left common carotid or left innominate artery

Isolation of the left common carotid or left innominate artery from the aortic arch is rare. A six week malformed infant with a right aortic arch had isolation of a left innominate artery and connection to the pulmonary artery by a left ductus arteriosus. A right ductus arteriosus had been ligated. Another infant with a right aortic arch and ostium primum atrial septal defect was shown to have an aberrant left subclavian artery arising from the lower descending aorta. The left common carotid artery filled retrogradely and drained into the pulmonary artery by a left ductus arteriosus. This abnormality has not been reported before.     

Isolation of the left common carotid or left innominate artery.

Isolation of the left common carotid or left innominate artery from the aortic arch is rare. A six week malformed infant with a right aortic arch had isolation of a left innominate artery and connection to the pulmonary artery by a left ductus arteriosus. A right ductus arteriosus had been ligated. Another infant with a right aortic arch and ostium primum atrial septal defect was shown to have an aberrant left subclavian artery arising from the lower descending aorta. The left common carotid artery filled retrogradely and drained into the pulmonary artery by a left ductus arteriosus. This abnormality has not been reported before.     

Atrial natriuretic polypeptide is removed by the lungs and released into the left atrium as well as the right atrium in humans

To examine the sites of release and removal of plasma atrial natriuretic polypeptide plasma levels in the femoral vein, right atrium, pulmonary artery, pulmonary capillary bed, left atrium and aortic root were measured in 11 control subjects and 22 patients with mitral stenosis. Mean plasma natriuretic polypeptide levels in the femoral vein, right atrium, pulmonary artery, pulmonary capillary bed, left atrium and aortic root were, respectively, 64 +/- 29, 124 +/- 72, 103 +/- 44, 83 +/- 30, 106 +/- 46 and 101 +/- 35 pg/ml in the control subjects and 321 +/- 170, 500 +/- 234, 458 +/- 266, 356 +/- 209, 434 +/- 222 and 432 +/- 217 pg/ml in the patients with mitral stenosis. In both the control subjects and the patients with mitral stenosis, there was a significant increase between the femoral vein and the right atrium and between the pulmonary capillary bed and the left atrium and a significant decrease between the pulmonary artery and the pulmonary capillary bed. Blood samples were also taken simultaneously from the pulmonary vein and the pulmonary capillary bed, as well as from the pulmonary artery and the left atrium, in 25 patients (11 control subjects, 5 patients with mitral stenosis and 9 patients with atrial septal defect). There was no difference in plasma atrial natriuretic polypeptide levels between the pulmonary capillary bed and the pulmonary vein in these 25 patients. It is concluded that atrial natriuretic polypeptide 1) is released into the left as well as the right atrium, and 2) is removed by the lungs.     

Congenitally corrected transposition of the great arteries: An update

Opinion statement  Congenitally corrected transposition of the great arteries is a rare condition in which systemic venous blood returns to normally positioned atria. However, the atria are connected to the opposite ventricle, right atrium to left ventricle, left atrium to right ventricle; so-called atrioventricular disordance. In addition, the ventricles are inverted (right to left change in position) and are connected to the opposite great artery, left ventricle to pulmonary artery, right ventricle to aorta; thus, forming ventricular-arterial discordance. The aorta is anterior and to the left of the pulmonary artery, L-transposed. Atrioventricular discordance plus ventricular-arterial discordance results in normal blood flow (ie, congenitally corrected). The right ventricle with the tricuspid valve is the systemic ventricle. Common associated conditions are ventricular septal defects (VSDs), pulmonary stenosis, and congenital heart block. Major issues related to management revolve around the status of the systemic right ventricle, which can develop dysfunction with increasing age and tricuspid regurgitation, which can increase in severity with age and contribute to ventricular dysfunction. One emerging treatment is the double switch operation. In patients with no pulmonary obstruction, it is possible to switch the systemic and pulmonary venous return using an atrial baffle procedure followed by an arterial switch procedure. This results in the anatomical left ventricle now functioning as the systemic ventricle. In those patients with associated pulmonary obstruction and a VSD, another type of double switch can be performed in which the left ventricle is tunneled through the VSD to the aorta, the right ventricle is connected to the pulmonary artery with a homograft or other conduit, and the atrial baffle procedure is performed. The most difficult challenge is choosing the patient who is a candidate for the double-switch operation and the timing of that operation, or the timing of a more classical operation for associated defects.     

Clinical implications of atrial isomerism

Right atrial isomerism or left atrial isomerism is frequently diagnosed as situs ambiguous without further discrimination of the specific morbid anatomy. Thirty six cases of right atrial isomerism and seven cases of left atrial isomerism were collected from the records and pathological museum at the National Taiwan University Hospital. There was a necropsy report for 18 cases. In all patients one or more of the following conditions was met: (a) isomeric bronchial anatomy, (b) echocardiographic and angiocardiographic evidence of isomerism, and (c) surgical or necropsy evidence of abnormal atrial anatomy. An anomalous pulmonary venous connection was present in 55% of patients with right atrial isomerism; in left atrial isomerism one case (14%) had a partial anomalous pulmonary venous connection. Forty per cent of cases of anomalous pulmonary venous connection with right atrial isomerism had obstruction. Six (86%) of seven cases with left atrial isomerism had an ambiguous biventricular atrioventricular connection. In contrast, univentricular atrioventricular connection (26 of 36, 72%) was significantly more common in right atrial isomerism. A common atrioventricular valve was the most frequent mode of connection in both forms. Two discrete atrioventricular valves were significantly more common in left atrial isomerism. Atrioventricular valve regurgitation was detected in 14 cases. Double outlet right ventricle was the most common type of ventriculoarterial connection. The most commonly cited causes of death after either palliative or definitive operation were undetected anomalous pulmonary venous connection, pulmonary venous stricture, and uncorrected atrioventricular valve or aortic regurgitation complicated by abnormal coagulation. Although the prognosis is poor, successful operation depends on knowledge of the precise anatomical arrangement associated with atrial isomerism.     

Clinical implications of atrial isomerism.

Right atrial isomerism or left atrial isomerism is frequently diagnosed as situs ambiguous without further discrimination of the specific morbid anatomy. Thirty six cases of right atrial isomerism and seven cases of left atrial isomerism were collected from the records and pathological museum at the National Taiwan University Hospital. There was a necropsy report for 18 cases. In all patients one or more of the following conditions was met: (a) isomeric bronchial anatomy, (b) echocardiographic and angiocardiographic evidence of isomerism, and (c) surgical or necropsy evidence of abnormal atrial anatomy. An anomalous pulmonary venous connection was present in 55% of patients with right atrial isomerism; in left atrial isomerism one case (14%) had a partial anomalous pulmonary venous connection. Forty per cent of cases of anomalous pulmonary venous connection with right atrial isomerism had obstruction. Six (86%) of seven cases with left atrial isomerism had an ambiguous biventricular atrioventricular connection. In contrast, univentricular atrioventricular connection (26 of 36, 72%) was significantly more common in right atrial isomerism. A common atrioventricular valve was the most frequent mode of connection in both forms. Two discrete atrioventricular valves were significantly more common in left atrial isomerism. Atrioventricular valve regurgitation was detected in 14 cases. Double outlet right ventricle was the most common type of ventriculoarterial connection. The most commonly cited causes of death after either palliative or definitive operation were undetected anomalous pulmonary venous connection, pulmonary venous stricture, and uncorrected atrioventricular valve or aortic regurgitation complicated by abnormal coagulation. Although the prognosis is poor, successful operation depends on knowledge of the precise anatomical arrangement associated with atrial isomerism.     

Peripheral and intracardiac levels of atrial natriuretic factor during cardiothoracic surgery.

Immunoreactive atrial natriuretic factor (ANF) levels were measured in blood taken from superior vena cava, right atrium, pulmonary artery, pulmonary vein, left atrium, and radial arteries in patients undergoing cardiac surgery. Significant (p less than 0.05) differences were seen between sites. Levels of atrial natriuretic factor were seen to rise from superior vena cava (27.5 pmol/L) to right atrium (54.3 pmol/L) and then fall in pulmonary artery (38.5 pmol/L). A further significant fall was seen in pulmonary vein (32.7 pmol/L) samples. There was no significant change in levels in left atrium (32.1 pmol/L) or radial artery (30 pmol/L). The fall between radial artery levels and superior vena caval levels was also significant. The rise from superior vena cava to right atrium is to be expected as this represents the major site of addition of atrial natriuretic factor to the circulation. We propose that the fall in levels from right atrium to pulmonary artery and from pulmonary artery to pulmonary vein suggests uptake and therefore possible local hormonal action on both right ventricle and pulmonary vasculature. The fall from radial artery to vena cava would be in keeping with atrial natriuretic factor's known systemic uptake and action.     

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.     

Backward transmission of the left atrial V wave and premature pulmonary valve closure

The concept that premature pulmonary valve closure may result from severe mitral insufficiency is presented. Five patients with severe mitral valve insufficiency had pulmonary arterial mean pressure which exceeded simultaneously recorded right ventricular mean systolic pressure. A high delayed pressure wave was present in the pulmonary artery of these subjects, and in four subjects the pulmonary arterial pressure rose above the right ventricular pressure. In two of the five, the timing and morphology of this pressure wave were suggestive of early closure of the pulmonary valve by retrograde transmission of the left atrial “V” wave through the pulmonary vessels. Catheterization revealed low cardiac indices, marked left atrial systolic pressure elevation, and elevated pulmonary artery pressure. All subjects had high total pulmonary resistance, while pulmonary arteriolar resistance was normal in three and only moderately elevated in two. The respective roles played by pulmonary arteriolar resistance, compliance of the left atrium and pulmonary vasculature, the state of left ventricular function, and amount of mitral regurgitation in the production of this phenomenon are discussed.     

Isolated atrial inversion Visceral situs solitus, visceroatrial discordance, discordant ventricular d loop without transposition, dextrocardia: Diagnosis and surgical correction

After cardiac catheterization and angiocardiographic studies an infant with cyanosis from birth was found to have visceral situs solitus, visceroatrial discordance without venoatrial discordance, a discordant ventricular d loop without transposition, and dextrocardia. The circulatory pathway was from the venae cavae to right atrium to left ventricle to aorta, and from the pulmonary veins to left atrium to right ventricle to pulmonary artery. An atrial defect was present allowing some mixing between the pulmonary and systemic circulations, but this appeared inadequate and the defect was enlarged surgically. Subsequently, a corrective operation using an atrial baffle to direct the pulmonary venous return to the left ventricle and the systemic venous return to the right ventricle was successfully undertaken.     

慢性阻塞性肺病患者心房颤动与心脏结构的关联性

目的 分析慢性阻塞性肺病（COPD）患者初发心房颤动与心脏结构的关联性。方法 将426例COPD患者分成窦性心律组（n=376）和初发房颤组（n=50）通过单因素分析得出COPD初发房颤的影响因素,再运用logistic回归分析COPD患者初发房颤的高危因素。结果 单因素分析显示与窦性心律组比较,初发房颤组患者在年龄、冠心病史、右心室内径（RVD）、左心房内径（LAD）、右心房内径（RAD）、肺动脉内径（PAD）方面差异具有统计学意义（P<0.05）,在初发房颤影响因素logistic回归分析中LAD（P<0.05）、RAD（P<0.05）是COPD患者初发房颤的危险因素。结论 COPD患者初发房颤与心脏结构有关联,左心房及右心房增大是COPD患者初发房颤的独立相关因素。     

Pulmonary atresia with intact atrial and ventricular septums, unroofed coronary sinus, and absent aortocoronary arterial connections

A stillborn fetus with pulmonary valvar atresia and intact atrial and ventricular septums also had absence of coronary arterial connections from the aorta and an unroofed coronary sinus. A left superior caval vein drained to the dilated coronary sinus. The left coronary artery was anomalously connected to the proximal branch of the right pulmonary artery, and a fistula from the right ventricle supplied the right coronary artery.     

Scanning suprasternal echocardiography.

Scanning suprasternal echocardiography was performed in 280 patients with a variety of cardiac anomalies. By using the special suprasternal transducer on the suprasternal notch, the aortic arch, right pulmonary artery, and left atrium were recorded superoinferiorly. From this reference position various scanning techniques were made to record the main pulmonary artery, pulmonary valve, ascending aorta, aortic valve, and distal aortic arch, wherever possible. These scans made it possible to assess (a) the integrity and size of right pulmonary artery and main pulmonary artery in pulmonary atresia, stenosis of origin of right pulmonary artery, pulmonary artery banding, kinked Waterston anastomosis, and aneurysm of pulmonary artery; (b) relative positions of aortic valve and pulmonary valve in malposition complexes; (c) the position and size of the aortic arch in tetralogy of Fallot and aortic coarctation. Measurements of the left atrium made by suprasternal echocardiography were consistently larger than those made by praecordial echocardiography. Changes in relative sizes of aortic arch, right pulmonary artery, main pulmonary artery, and left atrium were also documented in the various cardiac anomalies. The atrial baffle after Mustard repair for d-transposition of the great arteries and the atrial membrane in cor triatriatum were also demonstrated. The introduction of scanning techniques has thus widened the scope of suprasternal echocardiography.     

Large atrial myxoma causing mitral obstruction and severe pulmonary hypertension

Myxoma is the most common type of cardiac tumor, accounting for 30-50% of all primary cardiac tumors. Clinically, patients usually present with at least one of the classic triad of obstructive cardiac, embolic, and constitutional signs. The case is reported of a large atrial myxoma in the left atrium which caused mitral valve obstruction, leading to severe pulmonary hypertension and right heart failure, mimicking rheumatic mitral stenosis. Postoperatively, a fall occurred in the patient's pulmonary artery pressure and she showed clinical improvement.     

Bidirectional shunt in uncomplicated atrial septal defect

The presence of right to left shunts at atrial level in 40 patients with an uncomplicated atrial septal defect was determined by measuring the pulmonary vein to systemic artery oxygen stepdown . In six patients (group 1) a sizeable right to left shunt was found: left atrial oxygen stepdown was greater than or equal to 0.7 vol%, mean right to left shunt 0.67 1/min/m2 (range 0.36-1.0), and arterial oxygen saturation between 84% and 90.5%. The patients in group 1 did not show any differences from those with left to right shunts alone (group 2) as regards sex, cardiac rhythm, heart rate, "a" wave and mean right atrial pressure, end diastolic right ventricular pressure, morphology of diastolic right ventricular pressure curves, pulmonary to systemic vascular resistance ratio, size of the defect, and coexistence of anomalous pulmonary venous drainage. Patients with coexisting right to left shunts were, however, significantly older and had smaller left to right shunts. Thus an appreciable number of patients with uncomplicated atrial septal defects have major right to left shunts which are unrelated to pulmonary hypertension or right heart failure. These shunts may be detected by the usual oximetric techniques and apparently develop with age, which suggests that they result from changes associated with chronic right volume overload.