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.     

Clinical implications and possible association of malposition of the branch pulmonary arteries with DiGeorge syndrome and microdeletion of chromosomal region 22q11

We describe a series of 10 patients with malposition of the branch pulmonary arteries (4 patients with crossing [crossed pulmonary arteries] and 6 patients without crossing), 2 of whom had a short main pulmonary artery segment that resulted in iatrogenic right pulmonary artery stenosis after pulmonary artery band placement. DiGeorge syndrome was seen in 5 patients and 4 had microscopic deletion of chromosomal region 22q11.     

A new operative technique for pulmonary artery banding: adjustment of pulmonary artery bands by mitral valve flow velocity

We developed a new technique to adjust the pulmonary artery band at surgery by monitoring the mitral valve flow velocity, which is indirectly indicative of the pulmonary flow. We employed this technique for 10 consecutive patients aged from 5 days to 5 months (mean, 1 months) weighing from 2.7 to 4.4 kg (mean, 3.3 kg). Underlying disease was aortic coarctation or interrupted+ventricular septal defect in 7 patients, single ventricule in 1 patients and miscellaneous defects in 2 patients. The pulmonary artery was exposed through a left lateral thoracotomy and a 3 mm wide Teflon tape was placed around the main pulmonary artery. The transducer of the Doppler echocardiography was placed along the left sternal border. The band was tightened gradually until the maximum velocity of the mitral valve flow decreased to around 70% of the previous level. During banding procedure, arterial oxygen saturation, heart rate and left ventricular contractility were monitored continuously. If bradycardia, unacceptable hypoxemia or ventricular dysfunction occurred, the band was released. The mitral valve flow velocity decreased rapidly by just a little additional tightness of the band between the range of 50% to 80% of the previous level. This technique enabled a very fine adjustment (less than 0.5 mm plication) and postoperative management has become very easy. Although there is a limitation of this technique that monitoring of the mitral valve flow velocity cannot be applied to the patients with significant interatrial shunt or mitral regurgitation, we conclude that this technique is simple and useful to obtain the optimum constriction of the pulmonary artery with excessive pulmonary blood flow.     

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

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

Observation of relationship between function and structure of experimental pulmonary artery hypertension in rats and inhibitory effect of garlicin and other herbal medicines

The paper deals with the treatment of the pulmonary artery hypertention in rats caused by monocrotaline with garlicin, liqustrazine and berbamine and studies the relationship between the function and structure of pulmonary artery and pulmonary artery hypertension before and after use of hypotensive agents. The results show that there is a close relationship between the function and structure of pulmonary artery and pulmonary hypertension, and the inhibitory effect of garlicin is the strongest among the three herbal medicines. The pathogenesis is also studied.     

Device to limit inflation of a pulmonary artery catheter balloon

OBJECTIVE: The most serious complication seen with pulmonary artery catheters is rupture of the pulmonary artery. The effectiveness of an external safety balloon added to the pulmonary artery balloon inflation port was tested. DESIGN: The external balloon is designed to inflate and absorb excess volume from the inflation syringe after the internal balloon contacts the vessel wall. When the catheter tip is in a small pulmonary artery, expansion of the external balloon indicates that the catheter tip is in a noncompliant or small vessel. SETTING: The external balloon was tested in a bench simulation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The pulmonary artery balloon was slowly inflated inside 2.6-, 3.0-, 4.7-, 8.6-, and 11.6-mm internal diameter polyvinyl chloride tubes, with and without the external safety device in place. Without the external balloon, the average balloon pressure was 1647 +/- 145 (SD) mm Hg in the 2.6-mm vessel. With the external balloon in use, the maximum pulmonary artery balloon pressure was 473 +/- 7.2 mm Hg in the 2.6-mm vessel. CONCLUSIONS: The external balloon can limit balloon pressures within the pulmonary artery and identify when excessive volumes are being forced into the pulmonary artery balloon.     

Pulmonary artery sling

A case of pulmonary artery sling in a 1-year-old boy, treated by resection of the left pulmonary artery (LPA) at its origin from the right pulmonary artery (RPA) and reanastomosis of the LPA to the main pulmonary artery (MPA), is reported. In this patient the LPA-MPA anastomosis was demonstrated to be patent in a follow-up pulmonary angiogram six months after the operation. Pulmonary artery sling should be kept in mine when assessing respiratory distesss syndrome in children.     

Digital clubbing associated with pulmonary artery sarcoma

A case of digital clubbing in a patient with pulmonary artery sarcoma and severe pulmonary hypertension is presented. The differential diagnosis of clubbing and clinical features of pulmonary artery sarcoma are reviewed with emphasis on the possible association of clubbing with pulmonary artery sarcoma.     

Etest for routine clinical antimicrobial susceptibility testing of rapid-growing mycobacteria isolates

Tumors depend on their blood supply for growth. The blood supply to metastatic neoplasia of lung is usually from the pulmonary circulation or both the pulmonary and systemic circulation. The antineoplastic effect of pulmonary artery occlusion was investigated in a rat model of methylcholanthrene-induced metastatic pulmonary sarcoma. Left pulmonary artery ligation was performed on day 7 after tumor inoculation, and animals were sacrificed on day 14. The tumor burden of the left lung decreased 44% when compared with the control group. The survival of non-tumor-bearing rats undergoing left pulmonary artery ligation for 24 hours followed by right pneumonectomy after 2 weeks was also studied. No significant lung damage after a period of left pulmonary artery ligation was seen, as evidenced by both survival after contralateral right pneumonectomy and histology. Balloon occlusion of pulmonary artery, together with regional chemotherapy for patients with lung metastases, may warrant investigation.     

Mucor thermophilus spec. nov. and other Mucorales from India

We illustrate a case of so-called right pulmonary artery agenesis, discovered in a 3-month-old baby. This kind of malformation is rarely reported in neonatal age being most often discovered in the adulthood. The patient presented with cardiac failure, cyanosis and radiological features of cardiomegaly and left side pulmonary venous congestion. The diagnosis was strongly suspected by two-dimensional echocardiography and confirmed at cardiac catheterization. The patient was successfully operated upon with connection of main pulmonary artery to hilar right pulmonary artery. To the best of our knowledge, this is the first reported case of diagnosis and effective surgical therapy of right pulmonary artery agenesis in neonatal age.     

Blood flow in pulmonary and bronchial arteries in acute experimental pneumonia and pulmonary embolism

Acute lobar pneumonia and pulmonary embolism were induced in rabbits and the blood flow in the pulmonary artery and bronchial arteries was determined using isotopic microspheres. In acute pneumonia the pulmonary artery flow to the involved lung was reduced 8.5 times and the bronchial artery flow was reduced 5.0 times compared to flow in the normal lung. In acute pulmonary embolism, both the pulmonary artery flow (2.3 times) and the bronchial artery flow (2.5 times) were also reduced. For all animals, the reduction in pulmonary artery flow paralleled the reduction in bronchial artery flow (r=0.65).     

Variation in the size and distensibility of the pulmonary arteries in d-transposition of the great arteries

The relative size of the main pulmonary artery was determined from cineangiograms of 117 patients with d-transposition of the great arteries by calculating the ration between the diameters of the main pulmonary artery and aorta. The pulmonary artery was largest in patients with ventricular septal defect or patent ductus arteriosus, or both, because of increased pulmonary arterial pressure and flow. In patients with an intact ventricular septum or with left ventricular outflow tract obstruction, or both, the main pulmonary artery was approximately the size of the aorta. Two cases of d-transposition and gross dilatation of the main pulmonary artery and hypoplastic first branch pulmonary arteries are presented. In these cases the ratio between the diameters of the main pulmonary artery and aorta was greater than in any of the other 117 cases studied...     

Senning plus arterial switch operation for discordant (congenitally corrected) transposition

BACKGROUND: Congenitally corrected transposition of the great arteries is a complex cardiac lesion, usually associated with ventricular septal defect, left ventricular outflow tract obstruction, and tricuspid valve abnormalities. A subset of patients without left ventricular outflow tract obstruction have undergone Senning plus arterial switch operation in an attempt to place the left ventricle in the systemic circuit and the right ventricle in the pulmonary circuit. METHODS: Fourteen patients have had the operation performed since July 1989. Age and weight medians were 12 months (range, 0.5 to 120 months) and 8.2 kg (range, 3.2 to 34 kg). All but 1 patient had a left ventricular to right ventricular pressure ratio greater than 0.7, due to a large ventricular septal defect (with or without a previous pulmonary artery band), severe congestive heart failure caused by right ventricular dysfunction and tricuspid insufficiency, or a pulmonary artery band for left ventricular retraining. At least 10 patients had strong contraindications to "classic" repair, including right ventricular hypoplasia (n = 2), moderate to severe right ventricular dysfunction (n = 5), or moderate to severe tricuspid insufficiency (n = 9). RESULTS: There was one hospital death, occurring in a neonate (7%; 95% confidence interval = 0% to 34%). Actuarial survival beyond 10 months is 81% (95% confidence interval = 42% to 95%), currently with 389 patient-months of total follow-up time. The median grade of tricuspid insufficiency fell from 3/4 preoperatively to 1/4 postoperatively (p = 0.003). Right ventricular function is normal in 11/12 current survivors, all but 1 of whom are in New York Heart Association class I or II. CONCLUSIONS: Senning plus arterial switch operation is a good option for selected patients with congenitally corrected transposition of the great arteries with a similar or lower early risk (as compared with classic repairs). Some of the long-term problems associated with congenitally corrected transposition of the great arteries may be avoided with this strategy.     

Leiomyosarcoma of the pulmonary artery

Primary leiomyosarcoma of the pulmonary artery is an extremely rare tumor that is frequently misdiagnosed as chronic pulmonary embolism. In the present case, early diagnosis and location in the left pulmonary artery permitted resection by pneumonectomy with total cardiopulmonary bypass.     

Reconsideration of criteria for the Fontan operation. Influence of pulmonary artery size on postoperative hemodynamics of the Fontan operation

BACKGROUND: The outcome of the Fontan operation largely depends on the selection of patients because this procedure is a physiological correction. Among the several selection criteria for the Fontan operation, the importance of adequate size of the pulmonary artery remains controversial. In this series, in order to clarify whether the pulmonary artery size is indispensable or not as one of the selection criteria for the Fontan operation, we considered the physiological meaning of pulmonary artery size and investigated how it influenced postoperative hemodynamics of the Fontan operation. METHODS AND RESULTS: In congenital heart disease of decreasing pulmonary blood flow, 40 patients were examined for this analysis. Pulmonary artery indexes (cross-sectional area of the right and left pulmonary arteries divided by body surface area) were measured as the expression of pulmonary artery size, and the relations of pulmonary artery index (PAI) to pulmonary vascular resistance (Rp) and compliance (Cp) were studied. There was no significant correlation between PAI and Rp, whereas a significant correlation was found between PAI and Cp (r = .71, P = .001). Furthermore, Cp influenced postoperative hemodynamics of the Fontan operation by affecting the peak central venous pressure (pCVP) and total impedance, which was the afterload to the ventricle. Impedance increased abruptly when PAI was < approximately 100 mm2/m2. CONCLUSIONS: The smaller pulmonary artery size causes more disadvantageous hemodynamics after the Fontan operation, with resultant effects of the rise in pCVP and the increase in afterload to the single ventricle.     

Pulmonary artery catheterisation

The introduction of balloon-tipped pulmonary artery flotation catheters revolutionised monitoring of the cardiovascular system and the management of seriously ill patients. Advances in design allow direct measurement of cardiac output and continuous mixed venous oxygen saturation, while intracardiac electrocardiogram monitoring and passage of pacing wires is now possible. The technique of insertion must be meticulous as must the method of obtaining central venous, pulmonary artery, pulmonary artery wedge and pulmonary capillary wedge pressures. Sources of error are highlighted as are methods to avoid and detect them. Correct interpretation of the data is essential for proper patient management and must be taken in light of information obtained by other methods. Complications of insertion are numerous and potentially serious or even lethal. It is mandatory that the information obtained by insertion of a pulmonary artery catheter be used to optimize patient management.     

Density and localization of calcium channels of the L-type in human pulmonary artery

The pharmacological profile and the anatomical localization of Ca2+ channels of the L-type were investigated in the human pulmonary artery to identify possible mechanisms involved in the regulation of the pulmonary vascular tone. Analysis was performed on slide-mounted frozen sections of human pulmonary artery using radioligand binding assay techniques associated with light microscope autoradiography. [3H]-Nicardipine was used as ligand. Human renal and right coronary arteries also were used as systemic reference arteries. Binding of [3H]-nicardipine to sections of human pulmonary artery was time-, temperature- and concentration-dependent, saturable and reversible. In the human pulmonary artery, the apparent equilibrium dissociation constant (Kd) was 0.12+/-0.02 nM and the maximum density of binding sites (Bmax) was 38.15+/-2.25 fmol/mg tissue. Kd values were 0.3+/-0.01 nM and 0.5+/-0.02 in the human renal artery and right coronary artery respectively. Bmax values were 248+/-16 fmol/mg tissue and 173+/-9.5 fmol/mg tissue in the human renal artery and right coronary artery respectively. The pharmacological profile of [3H]-nicardipine binding to sections of human pulmonary artery was consistent with the labeling of Ca2+ channels of the L-type. It was similar in the pulmonary artery and in the human renal and right coronary arteries. Light microscope autoradiography revealed a high density of [3H]-nicardipine binding sites within smooth muscle of the tunica media of human pulmonary artery as well as of human renal and right coronary arteries. A lower accumulation of the radioligand occurred in the tunica adventitia. No specific binding was noticeable in the tunica intima. Our data suggest that human pulmonary artery expresses Ca2+ channels of the L-type sensitive to dihydropyridines. These sites have similar affinity and lower density than those expressed by systemic arteries. The presence of Ca2+ channels of the L-type in human pulmonary artery suggests that their pharmacological manipulation may be considered in the treatment of pulmonary hypertension.     

Consequences of a small decrease of air temperature from thermal equilibrium on thermoregulation in sleeping neonates

PURPOSE: To evaluate macromolecular contrast-enhanced MR-angiography for the detection of experimentally induced pulmonary artery embolism and to determine the size of the smallest detectable embolised vessel. METHODS: Pulmonary artery embolism was artificially induced in eight isolated perfused sheep lungs by injecting room air into the main pulmonary artery. The pulmonary vascular system enhanced by macromolecular gadolinium-DTPA-polylysine was imaged with a flow-sensitive gradient-echo technique. RESULTS: Pulmonary artery embolism was demonstrated in all eight lungs by an obvious cut-off phenomenon in the contrast-enhanced arteries proximal to the pulmonary air emboli. The smallest detectable embolised artery measured 1.6 mm in diameter and was located in the 6th generation of the pulmonary vascular system. CONCLUSIONS: In this experimental study MR angiography enhanced by a macromolecular contrast agent allowed noninvasive diagnosis of pulmonary artery embolism.     

Pulmonary arterial reconstruction with autologous pulmonary arterial tissue for pulmonary artery sling

One-year and two-month-old boy with pulmonary artery sling underwent pulmonary artery reconstruction with autologous pulmonary arterial tissue. Surgical repair consisted of the transection of the left pulmonary artery at its origin with trimming a button hole and the creation of an oval hole with the same size to the left pulmonary button. An autologous pulmonary patch and the left pulmonary button were exchanged and sutured to the former partner's place. He recovered uneventfully in post-operative course. Postoperative CT revealed a well developed left pulmonary artery from 5 mm to 10 mm in diameter without any distortion or stenosis. This exchange method could allow the natural growth of the anastomotic places without narrowing or distortion.     

Late re-interventions following arterial switch operations in transposition of the great arteries. Incidence and surgical treatment of postoperative pulmonary stenosis

Seventy-six patients were studied after arterial switch operation (ASO) between May 1977 and February 1992. Pulmonary artery reconstruction was initially performed by: conduit interposition in 5 patients, direct main pulmonary artery anastomosis and button patches in 60 patients, and pantaloon-like patch repair in 11 patients. Pulmonary stenosis developed in 17 patients (22%), requiring a total of 26 late re-interventions. Re-intervention was required in four out of five patients operated with pulmonary artery conduits, 11 out of 60 with a button patch repair and 2 out of 11 following pantaloon-type repair. In this series pulmonary artery stenosis (PS) involving the pulmonary valve occurred in 9/17 patients. Involvement of the pulmonary valve was related to the technique of pulmonary artery reconstruction. In these patients surgery is necessary. Balloon angioplasty can be a valuable tool when the stenosis is more distal. The incidence of PS was not influenced by the type of reconstruction or the use of Lecompte's maneuver.