Ultrasonic enhancement of myocardial infarction with perfluorocarbon compounds in dogs

Medically pure (100%) carbon dioxide directly injected into a peripheral vein was used for 2-dimensional contrast echocardiography in 134 patients with an arteriovenous shunt demonstrated by cardiac catheterization and cineangiography, Qp/Qs ratios of 1.5 to 3.7, pulmonary-to-systemic peak systolic pressure ratios of 0.2 to 0.8 and no oximetrically demonstrable venoarterial shunt. Two patients with transposition of the great arteries, intact ventricular septum and a Senning operation as well as 30 normal subjects of comparable age also were studied. In patients with an atrial septal defect, the gas microbubbles opacified the left atrium. In patients with a ventricular septal defect, the gas microbubbles opacified the left ventricle, whereas the left atrium was free of contrast. In all patients with patent ductus arteriosus, the gas microbubbles opacified the abdominal aorta, whereas the left atrium, left ventricle, aortic root and aortic arch remained free of contrast. In 2 patients in whom an aneurysm of the sinus of Valsalva ruptured into the right ventricle, the "negative" contrast effect permitted localization of the shunt. In 2 patients with transposition of the great arteries, an intact ventricular septum and a Senning operation, the intracardiac flow pattern was clearly demonstrated. No complication was observed. We conclude that pure carbon dioxide directly injected into a peripheral vein is a safe and advantageous echocardiographic contrast material. Because of its greater diffusibility in comparison with oxygen and fluid contrast media, small venoarterial shunting can be detected in defects such as atrial septal defect, ventricular septal defect and patent ductus arteriosus, in which only an arteriovenous shunt can be demonstrated by oximetry.     

Pulmonary blood flow distribution in transposition of the great arteries

Pulmonary blood flow distribution was studied by scintillation scanning of the lungs after the infusion of iodine-131-labeled macroaggregates of human albumin before and after the Mustard operation in 53 patients with transposition of the great arteries. The patients were classified as follows: Group I (24 infants with uncomplicated transposition of the great arteries); Group II (18 patients with transposition and ventricular septal defect); and Group III (11 patients with transposition, ventricular septal defect and pulmonary obstruction).Before operation, 21 patients had a normal distribution of pulmonary blood flow, 10 had preferential flow to the right lung and 2 had preferential flow to the left lung. After operation, 19 had a normal pattern of pulmonary blood flow, 21 had preferential flow to the right lung and 3 had preferential flow to the left lung. The scanning studies have proved helpful in follow-up of patients to rule out recurrence of the shunt, pulmonary or systemic venous obstruction, development of pulmonary hypertension and occlusion of a palliative systemic-pulmonary shunt.     

Ventricular septal defect with increased pulmonary vascular resistance. Late results of surgical closure

The fate of 57 children who underwent surgical closure of ventricular septal defect in the presence of increased pulmonary vascular resistance was analyzed. Eighteen (32 percent) died at or immediately after operation. Seven late deaths, due to the Eisenmenger syndrome, occurred 1 to 7 years after operation. Follow-up studies, including cardiac catheterization, were performed in 25 survivors, 1 to 11 years (mean 5 years) after operation. In patients operated on after age 2 years, the degree of preoperative elevation of pulmonary vascular resistance largely determined the prognosis: The condition of patients with mild elevation (pulmonary vascular resistance less than one third the systemic level) returned to normal after operation, with one exception. Patients with more severe elevation (pulmonary vascular resistance more than one third the systemic level) most often showed progressive pulmonary vascular disease; the condition of a few remained unchanged and that of only one returned to normal after operation.Operative mortality rate was high in children with elevated pulmonary vascular resistance during the second year of life who were operated on before age 2 years, but pulmonary vascular resistance returned to normal in the three survivors. When pulmonary vascular resistance was increased in the first year of life, it generally decreased spontaneously (independently of operation); the early increase in these cases is believed to represent delayed maturation of the pulmonary vascular bed rather than pulmonary vascular disease.The overall results of surgery in ventricular septal defect associated with a high level of pulmonary vascular resistance are unfavorable and call for interruption of the natural history before significant pulmonary vascular obstructive changes have taken place; this can be achieved by surgical closure before age 2 years or pulmonary artery banding in infancy.     

Mustard operation in the 1st month of life

Since April 1976, nine infants less than 1 month of age underwent a Mustard intraatrial baffle procedure. All had transposition of the great arteries and were persistently symptomatic or hypoxic after the Rashkind balloon atrioseptostomy. Two had an associated large ventricular septal defect patched at the time of physiologic correction. The average age of the infants was 11.6 days (range 36 hours to 28 days). Weight averaged 3.4 kg (range 2.5 to 4.2). In all the Mustard procedure was performed using deep hypothermie circulatory arrest, averaging 71 minutes (range 48 to 88) at a mean core temperature of 13 °C. An average of 2.8 days of postoperative ventilatory assistance was required. One death occurred in a 28 day old male infant with an associated ventricular septal defect who, the morning after operation, had a sudden unresponsive cardiac standstill. The postoperative hospitalization period averaged 15 days (range 10 to 23). Follow-up evaluation has extended from 4 to 63 months (average 31). Six patients were restudied 2 to 21 months postoperatively. One had obstruction of the superior limb of the baffle, which had separated from the right atrial wall permitting a modest right to left shunt. She has had uneventful repair employing a unique modification of Senning's operation. Another child has asymptomatic partial obstruction of the superior limb of the baffle demonstrated angiographically. None has pulmonary venous obstruction and all have prevailing normal sinus rhythm. Significant right ventricular dysfunction has been demonstrated in one. Early correction in these persistently symptomatic or hypoxic neonates with transposition of the great arteries with or without a ventricular septal defect has obviated the need for palliative operations and produced gratifying early and late results.     

Effect of respiratory acidosis on ventricular shunt flow and hemodynamics in dogs with ventricular septal defect

The effects of respiratory acidosis on ventricular shunt flow and hemodynamics were studied in 20 anesthetized dogs with a ventricular septal defect and a normal pulmonary vascular bed. The interventricular shunt flow was measured directly by using a specially designed electromagnetic flow probe. Respiratory acidosis was produced by hypoventilation and tachypnea with constant minute volume. Hypoxemia was also induced by hypoventilation, but not by tachypnea with constant minute volume. Systemic vascular resistance was increased in severe hypoventilation at 100 and 50 ml of tidal volume, and tachypnea at 100 ml of tidal volume. However the increase of pulmonary vascular resistance was observed in only severe hypoventilation: arterial pH 6.9, PaO2 24 mmHg, and PaCO2 88 mmHg. Left to right ventricular shunt flow and pulmonary blood flow were increased significantly with no change of systemic blood flow in both conditions of respiratory acidosis. The diastolic fraction of shunt flow was increased significantly. These findings indicate that the increase of left to right shunt flow in respiratory acidosis might be one of the risk factors of congestive heart failure for the patients with ventricular septal defect.     

Ultrasonic contrast studies for the detection of cardiac shunts

Contrast echocardiography has achieved importance in the diagnosis of cardiac shunt lesions. The technique provides information about flow patterns and serves as an adjunct to identifying communications that may be too small to image, even with high resolution real time scanning. This report reviews clinical applications and experiences in the use of standard, peripherally injected echocardiographic contrast agents for the detection of atrial septal defect, ventricular septal defect and patent ductus arteriosus. The importance and development of transpulmonary contrast agents capable of crossing the pulmonary capillary bed to opacify the left ventricle are reviewed and experience with a variety of experimental echocardiographic contrast agents is presented. Agents opacifying the left ventricle after intravenous injection are capable of providing direct ultrasonic contrast imaging of congenital left to right shunts. Further, recent experience with an experimental standardized, gas-producing contrast agent in an open chest animal model with an experimentally produced ventricular septal defect suggests that a combination of an experimental right heart agent that produces a measurable and reproducible amount of contrast effect, with a videodensitometric system capable of quantifying both positive and negative contrast effects, may provide an ultrasonic method for evaluating the magnitude of cardiac shunts.     

A neonate with mitral stenosis due to accessory mitral valve,ventricular septal defect,and patent ductus arteriosus: changes in echocardiographical findings during the neonatal period

 A female neonate with mitral stenosis due to accessory mitral valve with ventricular septal defect and patent ductus arteriosus is described. She was referred to our hospital because of neonatal asphyxia. Asphyxia was improved by ventilator support, but rapid deterioration of respiration with pulmonary congestion and hemorrhage appeared 8 days after birth. Echocardiography revealed an accessory mitral valve attached to the anterior mitral leaflet with a perimembranous ventricular septal defect and patent ductus arteriosus. Although there were no echocardiographical findings indicating mitral stenosis on admission, the mitral stenosis blood flow patterns were detected by color and pulsed Doppler examination performed on the eighth day after admission. Transaortic resection of accessory mitral valve tissue was performed with patch closure of the ventricular septal defect and ligation of the ductus arteriosus 35 days after birth. After operation, pulmonary congestion and hemorrhage were improved. Postoperative echocardiography showed complete resection of the accessory mitral valve and no mitral insufficiency. We concluded that the combination of the accessory mitral valve and left-to-right shunt due to ventricular septal defect or patent ducturs arteriosus might have led to a critical hemodynamic condition due to relative mitral stenosis in the neonatal period with the decrease in pulmonary vascular resistance. Received: May 30, 2002 / Accepted: September 6, 2002 Correspondence to T. Ito     

Two-dimensional echocardiographic identification of hemitruncus: Anomalous origin of one pulmonary artery from ascending aorta with the other pulmonary artery arising normally from right ventricle

Two-dimensional echocardiography (2DE) was performed on a 2300 gm newborn who presented with congestive heart failure. Clinical examination suggested left-to-right shunt with pulmonary hypertension. Cardiac catheterization and angiography demonstrated origin of the right pulmonary artery (RPA) from the aorta. Retrospectively, this feature (anomalous RPA) had been present on 2DE. A second patient aged 2 years had evidence of ventricular septal defect with large left-to-right shunt early in life. Gradual development of infundibular stenosis and clinical cyanosis ensued. 2DE showed subaortic ventricular septal defect with infundibular stenosis. Cardiac catheterization and angiography confirmed tetralogy of Fallot with origin of the left pulmonary artery (LPA) from the aorta. Retrospective review of 2DE showed the anomalous LPA arising from the side of the ascending aorta.     

Results of the arterial switch operation for transposition of the great arteries with ventricular septal defect. Surgical considerations and midterm follow-up data

Between January 1983 and December 1987, 62 patients underwent an arterial switch operation for transposition of the great arteries with ventricular septal defect or double outlet right or left ventricle. There were three hospital deaths (4.8%), and no deaths occurred in neonates (less than 1 month of age, n = 18). There were three late deaths, one due to coronary obstruction and two due to pulmonary vascular obstructive disease. One child has been lost to follow-up. We have prospectively evaluated the remaining 55 survivors by clinical evaluation, echocardiography, cardiac catheterization, ambulatory electrocardiographic monitoring, and limited electrophysiologic studies. The mean length of follow-up has been 27 +/- 16 months since surgery. One child has required reoperation for a residual ventricular septal defect; no child has undergone reoperation for supravalvar pulmonary or aortic stenosis. Aortic regurgitation was identified in 12 children (22%), which was mild in 11 and moderate in one. One child has asymptomatic occlusion of the left main coronary artery, one child has a tiny right coronary artery-to-pulmonary artery fistula, and one child has abnormal left ventricular wall motion according to follow-up angiography. No other abnormalities of systemic (left) ventricular function have been identified at late follow-up. In addition to the two late deaths due to pulmonary vascular obstructive disease, three children, all of whom were repaired at more than 6 months of age, have elevated pulmonary vascular resistance. Notable postoperative arrhythmias include complete heart block in four patients and nonsustained supraventricular or ventricular tachycardia early after surgery in eight patients (all resolved without medication at later follow-up). Only two patients have evidence of sinus node dysfunction and have not required treatment. The low hospital mortality and encouraging early follow-up data represent a significant improvement over atrial level repairs, supporting the arterial switch operation as the procedure of choice for children who have transposition of the great arteries with ventricular septal defect or double outlet ventricle. Because of the potential for the development of early pulmonary vascular obstructive disease in these patients, repair is recommended within the first 2 months of life.     

Supravalvular stenosing ring of the left atrium associated with corrected transposition of the great vessels

A case of supravalvular stenosing ring of the left atrium is described. The severity of the stenosis obscured the features of Ebstein's malformation of the left atrioventricular valve, which was the only other defect associated with corrected transposition. Analysis of the reported examples of supravalvular stenosing rings reveals that the condition rarely exists as an isolated anomaly but tends to occur in 2 groups of conditions, namely, a developmental complex of obstructive anomalies of the left side of the heart (supravalvular ring, subaortic stenosis, parachute mitral valve and coarctation of the aorta) or a second group associated with a left to right shunt produced by a ventricular septal defect or patent ductus arteriosus. The potential diagnostic value of echocardiography in cases in which there is evidence of pulmonary venous obstruction is discussed.     

Congenital unilateral pulmonary vein stenosis complicating transposition of the great arteries

Four patients with transposition of the great arteries and unilateral pulmonary vein (PV) stenosis, all left-sided, were studied. Two patients had an intact ventricular septum (1 with a patent ductus arteriosus), 1 patient had a ventricular septal defect and 1 had a ventricular septal defect with pulmonary stenosis. Clinical signs, such as recurrent pneumonia, unilateral pulmonary edema and pleural effusion, were present preoperatively in 2 patients. Diagnosis was made at cardiac catheterization by cineangiography in 2 patients and at Mustard operation when the PV orifices were inspected in the other 2. PV dilatation was attempted in 3 patients, 1 before correction (age 6 months), 1 during and after it (ages 1 and 3 years, respectively) and 1 during corrective surgery (age 15 months). In the fourth patient only the intracardiac baffle was enlarged near the left PV orifices. In the first patient, at Mustard operation (age 18 months), only a fibrotic PV without an orifice was found; this patient died after surgery. The mean follow-up in the 3 survivors was 3.2 years (range 2 months to 7.6 years). All have severe residual PV obstruction documented by technetium-99m lung perfusion scans that show decreased flow to the left lung (0 to 16% total counts; normal 45 %); 2 have unilateral pulmonary edema and 1 has pulmonary artery pressure at systemic level. It is believed that in patients with transposition of the great arteries, left-sided unilateral PV stenosis is a congenital anomaly that becomes progressive as a result of postnatal preferential flow to the right lung.     

Pulmonary vascular disease in complete transposition of the great arteries: A study of 200 patients

Lung specimens of 200 patients with transposition of the great arteries were examined microscopically for evidence of pulmonary vascular disease. In patients with an intact ventricular septum or a small ventricular septal defect, advanced pulmonary vascular disease was uncommon; only 9 of 107 such patients (8.4 percent) demonstrated greater than grade 2 (Heath-Edwards) pulmonary vascular disease. A persistent large patent ductus arteriosus appeared to promote progressive pulmonary vascular disease in this group since each of the five infants less than 1 year of age with grade 3 or 4 disease had this lesion. In contrast, pulmonary vascular disease was common in patients with a large ventricular septal defect; 37 of 93 patients (40 percent) with this defect had greater than grade 2 pulmonary vascular disease. Among patients more than 1 year of age, 26 of 35 (75 percent) had grade 4 disease. The catheterization data suggest that the calculated pulmonary vascular resistance may underestimate the degree of disease, probably by overestimating the pulmonary blood flow (Fick method). Pulmonic stenosis appeared to protect the lungs from progressive pulmonary vascular disease, and pulmonary arterial banding was protective when performed before age 6 months. Our studies indicate that a persistent large patent ductus arteriosus should be closed as early as possible in view of its association with advanced pulmonary vascular disease in these patients. In infants with a large ventricular septal defect, pulmonary arterial banding or corrective surgery with closure of the defect should be performed between the ages of 4 and 6 months to prevent progressive pulmonary vascular damage.     

Long-term follow-up study after closure of secundum atrial septal defect in children: An echocardiographic study

Serial echocardiography was performed in 51 children with isolated secundum atrial septal defect before and after surgery to measure the effects of chronic right ventricular overload on ventricular function. Right ventricular dilation increased dramatically with growth and with size of the left to right shunt only in the youngest children (body surface area less than 0.5 m²). A lesser effect of growth and no significant effect of shunt size were noted in older children.Although an initial decrease in right ventricular size occurred in the first 3 months after operation, persistent right ventricular dilation remained up to 5 years after closure of the interatrial defect in more than 80 percent of patients. Preoperatively, the ratio of the right ventricular preelection period to ejection time was significantly less than that of normal children. This ratio increased dramatically after operation, exceeding normal values early in the postoperative period in 18 of 48 children and persisting in 6 of 22 after 3 months. Left ventricular dimensions were normal early and late after operation. Left ventricular function was apparently normal, although] an exceptionally high shortening fraction was noted in 22 (44 percent) of 51 children after operation. Aortic systolic time interval ratios decreased after operation from high normal to low normal values.It is hypothesized that the persistent enlargement of the right ventricle after operation may be due to the chronic preoperative dilation secondary to chronic interatrial shunting. The abnormally high shortening fraction after operation may result from an abnormal left ventricular geometric configuration or abnormality of filling. It is suggested that surgical closure of the atrial defect in the first 3 years of life may prevent these abnormalities.     

Acute haemodynamic effects of nifedipine in patients with ventricular septal defect.

The haemodynamic effects of nifedipine were studied in 14 patients (aged 8-14 years, seven male and seven female) with ventricular septal defect with and without pulmonary hypertension. All underwent left and right heart catheterisation. In each patient the pressures and heart rate were measured and blood samples were taken for oximetry before and after sublingual administration of 10 mg nifedipine. In eight patients with ventricular septal defect without pulmonary hypertension (mean pulmonary artery pressure less than 20 mm Hg) nifedipine significantly reduced the mean aortic pressure and systemic vascular resistance, and significantly increased heart rate. The other haemodynamic indices did not change significantly. In six patients with ventricular septal defect complicated by pulmonary hypertension (mean pulmonary artery pressure greater than 20 mm Hg) nifedipine significantly increased systemic output, stroke volume, and heart rate, and significantly reduced systemic vascular resistance and the pulmonary to systemic flow ratio. The other haemodynamic indices did not change significantly. Nifedipine had a beneficial effect in patients with ventricular septal defect complicated by pulmonary hypertension. It reduced the left to right shunt and increased the stroke volume. This effect was not seen in patients with ventricular septal defect uncomplicated by pulmonary hypertension.     

Acute haemodynamic effects of nifedipine in patients with ventricular septal defect

The haemodynamic effects of nifedipine were studied in 14 patients (aged 8-14 years, seven male and seven female) with ventricular septal defect with and without pulmonary hypertension. All underwent left and right heart catheterisation. In each patient the pressures and heart rate were measured and blood samples were taken for oximetry before and after sublingual administration of 10 mg nifedipine. In eight patients with ventricular septal defect without pulmonary hypertension (mean pulmonary artery pressure less than 20 mm Hg) nifedipine significantly reduced the mean aortic pressure and systemic vascular resistance, and significantly increased heart rate. The other haemodynamic indices did not change significantly. In six patients with ventricular septal defect complicated by pulmonary hypertension (mean pulmonary artery pressure greater than 20 mm Hg) nifedipine significantly increased systemic output, stroke volume, and heart rate, and significantly reduced systemic vascular resistance and the pulmonary to systemic flow ratio. The other haemodynamic indices did not change significantly. Nifedipine had a beneficial effect in patients with ventricular septal defect complicated by pulmonary hypertension. It reduced the left to right shunt and increased the stroke volume. This effect was not seen in patients with ventricular septal defect uncomplicated by pulmonary hypertension.     

Unusual vascular ring in infant with pulmonary atresia and ventricular septal defect.

A 3-day-old infant investigated for cyanotic heart disease was found to have partial DiGeorge syndrome and pulmonary atresia with ventricular septal defect. The only source of pulmonary blood flow was a right-sided persistent ductus arteriosus which originated from an aberrant right subclavian artery. Such a vascular ring has not been described previously. Surgical treatment included a left-sided prosthetic shunt in infancy followed by resection of the ligamentum arteriosum and right subclavian artery during the second year of life.     

心室间隔缺损心电图心室肥厚与肺动脉压力、缺损大小和分流量的对比分析

目的：分析８３例心室间隔缺损（ＶＳＤ）患者术前心电图改变与血流动力学及缺损大小之间的关系，为ＶＳＤ术前提供初步预测性意见。方法：依据心电图分为正常、左心室肥厚、右心室肥厚和双心室肥厚４组，与右心导管检查所测肺动脉压力和阻力、左向右分流量和术中所见缺损大小、心室壁厚度进行对比。结果：心电图为左心室肥厚、心室间隔为中小缺损且呈中大分流量者，肺动脉压力多为轻中度增高；心电图为右心室肥厚和双心室肥厚，心室间隔多为中大缺损且分流量大者多有重度肺动脉高压，右心室肥厚，肺总阻力增高较双心室肥厚者严重。与术中所见心室壁肥厚比较，心电图诊断左、右心室肥厚符合率较高，分别为１００．０％及８５．７％，但心电图正常者中有７８．６％术中所见为左心室肥厚。结论：ＶＳＤ心电图改变可以间接评估其血液动力学改变及缺损大小。     

Change in pulmonary and systemic circulation in acute ventricular septal defect

The correlation between left to right ventricular (L-R) shunt flow and other hemodynamic changes was studied in 16 dogs with an acute ventricular septal defect (VSD) and normal pulmonary vascular bed. The interventricular shunt flow was measured directly with a specially designed electromagnetic flowmeter probe, where the area of the VSD was constant. The sudden presentation of VSD increased pulmonary arterial pressure, pulmonary flow and left ventricular end-diastolic pressure. L-R shunt flow was not changed significantly by atrial pacing except when the rate was increased to over 200/min. Dogs with a VSD were treated with isoproterenol and dextran to vary the shunt flow and hemodynamic parameters. L-R shunt flow was decreased by isoproterenol and increased by dextran loading. The percentage changes of L-R shunt flow from pre-drug values correlated well with the change in left ventricular end-diastolic pressure (r = 0.75) and the ratio of pulmonary to systemic vascular resistance (r = -0.73). Change in total pulmonary vascular resistance had a greater effect on L-R shunt flow than did a change in systemic vascular resistance, whereas a change in aortic flow had less effect (r = 0.35) on L-R shunt flow than did a change in preload and afterload. The time to peak LV dP/dt, as an index of cardiac contractility, and heart rate were not correlated with the relative change in L-R shunt flow. These results indicate that L-R shunt flow induced by the sudden presentation of a VSD varied with changes in the pulmonary and systemic circulation.     

Occlusion of azygos vein via direct percutaneous puncture of innominate vein following cavopulmonary anastomosis

A 2-year-10-month-old boy was diagnosed with a complex congenital heart disease: right atrial isomerism, left superior vena cava (LSVC), complete atrioventricular septal defect, secundum type atrial septal defect, transposition of the great arteries with pulmonary atresia, patent ductus arteriosus, absence of a right superior vena cava (RSVC), and dextrocardia. He had received a left Blalock-Taussig (BT) shunt at the age of 3 months and a left bidirectional Glenn shunt one year after BT shunt. Progressive cyanosis was noted after the second operation and cardiac catheterization showed a functional Glenn shunt with an engorged azygos vein, which was inadvertently skipped for ligation. Because of the absence of RSVC, transcatheter occlusion of the azygos vein was performed successfully via direct puncture of the innominate vein.     

Critical aortic coarctation: patch aortoplasty in infants less than age 3 months.

Twenty-three infants less than age 3 months (mean age 31 days) underwent patch aortoplasty for relief of coarctation of the aorta. All had intractable congestive heart failure, despite aggressive medical therapy. Each infant had other cardiac anomalies, including patent ductus arteriosus (83 percent) and ventricular septal defect (74 percent). All patients underwent closure of the ductus arteriosus and patch angioplasty of the aorta to produce a luminal diameter of at least 16 mm. In addition, 9 of the 17 patients (53 percent) with a large shunt ventricular septal defect underwent pulmonary arterial banding. There was one hospital death 42 days after operation secondary to bowel perforation and sepsis. Hospitalization beyond 21 days postoperatively was always due to other unrepaired cardiac lesions. The three late deaths at 3, 9 and 18 months after operation were associated with additional major anomalies. Fourteen patients have had postoperative catheterization. No gradient was found across the site of coarctation repair, but one patient had a gradient between the left carotid and left subclavian arteries. Surgical repair of critical coarctation of the aorta in infants can safely be offered despite the presence of other cardiac anomalies.