Nonselective preoperative digital subtraction angiography of internal mammary arteries

In preparation for coronary bypass surgery, digital subtraction angiography (DSA) was used to assess the caliber of the left and right internal mammary arteries and to exclude stenoses of their feeding arteries. In 100 patients (86 males, mean age 56 +/- 9 years) DSA was performed with a Siemens Digitron 2 device. A frontal projection was used in 18 patients, and a 10-20 degree right anterior oblique projection was used in 82 patients. The flow was 10 to 25 ml/sec; 20 ml was injected in 45 patients, 30 ml in 41, 40 ml in 5, 50 ml in 8, and 60 ml in 1 patient. Judged on the proximal third, visualization of the left and the right internal mammary artery was good in 80 and 72, fair in 17 and 20, and bad in 3 and 8 arteries, respectively. The diameter (mm) was 2.7 +/- 0.4 (range 1.8-3.4) and 2.7 +/- 0.3 (range 2.0-3.5), and visible length (cm) was 8 +/- 5 (range 1-24) and 9 +/- 4 (range 2-22) for the two arteries, respectively. The 10-20 degree right anterior oblique view separated the left internal mammary artery better from the descending aorta than the frontal view. In more pronounced right anterior oblique views the ascending aorta interfered with the right internal mammary artery. The quality was not different with 20 ml or 30 ml injections. The feeding arteries could not be assessed in 4 patients. One left subclavian artery was found occluded at the orifice. Incidentally, 2 distal right subclavian stenoses and 2 carotid stenoses were detected.(ABSTRACT TRUNCATED AT 250 WORDS)     

Association of chromosome 22q11 deletion with isolated anomalies of aortic arch laterality and branching

OBJECTIVES

The purpose of this study was to determine the frequency of chromosome 22q11 deletions in patients with isolated anomalies of the aortic arch and its branches.

BACKGROUND

Chromosome 22q11 deletions are often present in patients with certain forms of congenital cardiovascular disease, including tetralogy of Fallot, truncus arteriosus and interruption of the aortic arch. Among patients with these anomalies, chromosome 22q11 deletion is more common in those with abnormal aortic arch laterality or branching.

METHODS

We studied 66 patients with isolated anomalies of the aortic arch and no associated intracardiac defects for deletions within chromosome 22q11, using fluorescence in situ hybridization with the cosmid probe N25 (D22S75). Arch anomalies included: double aortic arch (n = 22); right aortic arch with aberrant left subclavian artery (n = 28); right aortic arch with mirror-image branching and a vascular ring formed by a left-sided ductus from the descending aorta (n = 5); right aortic arch with mirror-image branching and no vascular ring (n = 4); and left aortic arch with aberrant right subclavian artery (n = 7). In addition, four patients had a cervical aortic arch, four had aortic coarctation and six had hypoplasia/atresia of the proximal pulmonary arteries.

RESULTS

Chromosome 22q11 deletions were found in 16 patients (24%) across the full spectrum of anomalies studied. Among the morphologic variables analyzed, only hypoplasia/atresia of the proximal pulmonary arteries correlated with the deletion (p = 0.03). Among patients with a double arch, the frequency of chromosome 22q11 deletion was higher in those with an atretic minor arch than it was in those with a patent minor arch (p = 0.02).

CONCLUSIONS

Chromosome 22q11 deletion is associated with isolated anomalies of laterality or branching of the aortic arch in 24% of cases in our series. These findings should alert the clinician to consider deletion screening in patients with isolated anomalies of the aortic arch.     

Takayasu arteritis: usefulness of radiologic and angiographic studies

With the purpose of learning the usefulness of radiologic and angiographic procedures for the evaluation of Takayasu's arteritis (TA), we studied 64 patients (ratio women: 8.1, average age: 23.5 years, range: 13-52 years) in which we performed arteriographic studies in the clinically affected area. All cases had chest films: 53 had thoracic aortogram, 60 abdominal aortogram, 16 pulmonary arteriography. According to the topography of the lesions we found 8% of the cases with damage exclusive to the supra-aortic trunk, 6% with isolated alteration of the intermediate thoraco-abdominal aorta, 62% with mixed pathology of the two categories above, and 21% with lesions in the pulmonary artery besides systemic arteriopathy. The results were as follows: 1) radiology of the chest: cardiomegaly (48%), irregularities in the ascending aorta (31%), calcification in the aortic wall (29%), calcified granulomas (25%) and signs of pulmonary venous hypertension (21%); 2) thoracic aortogram: irregularities in the descending aorta (56.6%), thickening of the wall of descending aorta (39.6%), dilatation of the ascending aorta (26.4%), of the descending aorta (26.4%); occlusions: of the left subclavian (24 cases), left mammary (16 cases), left carotid (8 cases) and left vertebral (8 cases); 3) abdominal aortogram: irregularities of the outline, stenosis, prominent "supplementary" arteries and aneurysms in 53%, 43.3%, 38% and 13.3 of the studies performed. The arteries most commonly affected were: renal (74.7%), both (31.6%), right (28.2%) and left (14.9%), superior mesenteric (26.6%) and hepatic (21.6%); 4) pulmonary arteriography: arterial occlusions: right superior lobar branch (37.5%), right medial (6.2%), right inferior (12.5%), without predilection by any lobe; 5) coronary arteriography: one case with occlusion of anterior descending artery and circumflex coronary artery (the other 8 cases without significant lesions). We concluded that TA affects independently the arteries of different areas, hence it is necessary to perform multiple angiographic studies for adequate evaluation of the extension of vascular damage.     

Early results and follow-up of balloon angioplasty for branch pulmonary artery stenoses

Two hundred eighteen balloon angioplasty procedures were performed in 135 patients with branch pulmonary artery stenoses from June 1984 to February 1989. Arteries were dilated in patients with tetralogy of Fallot (n = 49), tetralogy of Fallot/pulmonary atresia (n = 64), isolated peripheral pulmonary artery stenoses (n = 58) and "other" lesions (the majority had truncus arteriosus or single ventricle and surgically induced pulmonary artery stenoses (n = 47). Mean age at dilation was 6.6 +/- 6.3 years (range 1 month to 38.5 years). The mean diameter of the lesion increased from 3.8 +/- 1.7 to 5.5 +/- 2.1 mm with dilation (p = 0.001). The overall success rate was 58% (127 of 218 dilations), assessed by the following criteria: an increase greater than or equal to 50% of predilation diameter, an increase greater than 20% in flow to the affected lung or a decrease greater than 20% in systolic right ventricular to aortic pressure ratio. Success did not correlate with patient age. Mean balloon to artery ratio was higher in successful (4.2) than in failed (3.0) angioplasty procedures (p = 0.0001). There were four early deaths: two of the patients had pulmonary artery rupture with angioplasty performed less than 1 month after pulmonary artery surgery. An aneurysm occurred in 11 arteries and transient pulmonary edema in four patients. At angiography performed a mean of 10 months (range 1 to 54) after dilation, the mean diameter of 57 arteries was unchanged (5.5 versus 5.4 mm). However, 5 of 32 initially successfully dilated vessels had returned to predilation size as a result of restenosis.(ABSTRACT TRUNCATED AT 250 WORDS)     

The diameters of the aorta and its major branches in patients with isolated coronary artery ectasia

We designed this study to evaluate the diameters of the aorta and its major branches in patients who had coronary ectasia. We assigned 80 patients (mean age, 57 +/- 11 yr) with isolated coronary artery ectasia to the study group and 25 patients (mean age, 54 +/- 10 yr) without structural or coronary arterial disease to the control group. All patients underwent coronary angiography and angiography of the aorta and its branches. We used computed quantitative angiography to measure the diameters of the coronary arteries, the aorta, and the major aortic branches. Within the study group, the diameter indices of the proximal portions of the right common iliac artery (P=0.041) and the left common iliac artery (P=0.035) were significantly larger than the diameter indices within the control group. The diameter indices of all other evaluated arteries were similar in both groups (all P >0.05).     

Analysis of intracardiac shunting in the lizard, Varanus niloticus: a new model based on blood oxygen levels and microsphere distribution

The central sites of the cardiovascular system (right and left aortic arches, RAo and LAo, pulmonary artery, PA, and right and left atria, RAt and LAt) were chronically and non-occlusively cannulated for an analysis of intracardiac shunting in Varanus niloticus. Oxygen partial pressure (PO2) and oxygen concentration (CO2) were significantly higher in right aortic blood than values determined in left aortic blood. The difference was larger in animals acclimated to 25 degrees C (RAo CO2 = 4.5 +/- 1.00 vol %, LAo CO2 = 3.8 +/- 1.14, X +/- SD, n = 19) than at 35 degrees C (RAo CO2 = 5.8 +/- 1.24, LAo CO2 = 5.4 +/- 1.35, n = 18) (P less than 0.001 for both temperatures, paired t-test). These data are explained by a new model describing the differential shunting patterns of the two aortae in addition to the conventional overall right-to-left and left-to-right shunt fractions. This model was solved on the basis of blood gas data collected by simultaneous multiple-site gas analysis, together with data on the differential blood flow in the central vascular system, collected by application of the microsphere method. At 35 degrees C both right-to-left and left-to-right shunts were relatively small (about 9%), with the right-to-left shunt fraction directed exclusively into the left aorta. Thus right aortic blood represented left atrial blood, whereas left aortic blood was composed of 80% left atrial and 20% right atrial blood. Ninety percent of the pulmonary arterial blood was derived from the right atrium and 10% from the left atrium. At 25 degrees C the composition pattern of effluent blood for each vessel was similar, the absolute flow distribution, however, was different from that at 35 degrees C. These findings are discussed with respect to their significance and compatibility with the wash-out shunt model.     

短暂性脑缺血发作的数字减影血管造影及颈部动脉超声评价

目的 评价数字减影血管造影(digital subtraction angiography,DSA)和颈动脉超声对短暂性脑缺血发作(transient ischemia attack,TIA)的诊断价值.方法 74例TIA患者中,颈内动脉(internal carotid artery9 ICA)系统TIA45例,椎基底动脉(vertebrobasilar artery,VBA)系统TIA 29例,均行DSA检查以了解两系统颅内外动脉狭窄情况,行颈动脉超声检查以了解动脉斑块分布情况.结果 DSA检查显示,ICA系统TIA患者血管狭窄检出率为84.4%(38例),重、中、轻度狭窄分别为31.1%(14例)、26.7%(12例)和11.1%(5例),其中颅内动脉狭窄为44.4%(20例),显著高于颅外动脉狭窄的22.2%(10例)(P＜0.001);VBA系统TIA患者血管狭窄检出率为65.5%(19例),重、中、轻度狭窄分别为17.2%(5例)、27.5%(8例)、20.7%(6例),其中颅外动脉狭窄为44.8%(13例),显著高于颅内动脉狭窄的13.8%(4例)(P＜0.001).颈动脉超声检查显示,ICA系统TIA患者ICA斑块检出率为44.4%(20例),高于VBA系统TIA患者的24.1%(7例);VBA系统TIA患者锁骨下动脉起始段斑块检出率为44.8%(13例),显著高于ICA系统TIA患者的13.3%(6例)(P＜0.001).结论 ICA系统和VBA系统TIA患者颅内外血管病变和动脉硬化斑块分布存在差异,前者以颅内病变多见,后者则以颅外病变多见.     

Anomalous origin and course of the coronary arteries

In the normal heart, the right and left coronary arteries arise from the aortic valvar sinuses adjacent to the pulmonary trunk. The right coronary artery then directly enters the right atrioventricular groove, whereas the main stem of the left coronary artery runs a short course before dividing to become the anterior interventricular and circumflex arteries. These arteries can have an anomalous origin from either the aorta or pulmonary trunk; their branches can have various anomalous origins relative to arterial pedicles. Other abnormal situations include myocardial bridging, abnormal communications, solitary coronary arteries, and duplicated arteries. Understanding of these variations is key to determining those anomalous patterns associated with sudden cardiac death. In the most common variant of an anomalous origin from the pulmonary trunk, the main stem of the left coronary artery arises from the sinus of the pulmonary trunk adjacent to the anticipated left coronary arterial aortic sinus. The artery can, however, arise from a pulmonary artery, or the right coronary artery can have an anomalous pulmonary origin. The key feature in the anomalous aortic origin is the potential for squeezing of the artery, produced by either the so-called intramural origin from the aorta, or the passage of the abnormal artery between the aortic root and the subpulmonary infundibulum.     

Fetal echocardiography. A horizontal study of biometry and cardiac function in utero

The anatomy and the cardiac growth in normal fetal heart was studied by real-time-directed M-mode ultrasound from the 19th gestation week until term. A correct fetal cardiac M-mode recording was obtained in 94 out of 144 women (65%). Echocardiographic variables were plotted against gestational age and respective correlation coefficients were determined by linear regression analysis. A comparison between the variables was studied by paired t-test. Left ventricular, right ventricular, left atrial and right atrial chamber size, interventricular septum thickness, right and left wall thickness, aortic and pulmonary diameter all increased linearly with age. Right ventricle (10.1 +/- 3.1) was slightly larger than left ventricle (9.2 +/- 2.8 mm) (p less than 0.001), the pulmonary artery (7.9 +/- 1.9 mm) was greater than the aorta (7.6 +/- 2 mm) (p less than 0.001), while no significant difference was noted between left atrium (10.8 +/- 3.5 mm) and right atrium (10.1 +/- 2.6 mm), right ventricular wall thickness (2.7 +/- 0.9 mm) and left ventricular wall thickness (3.0 +/- 1.1 mm). The ratios of left ventricular/right ventricular diameter, left atrial/right atrial and left atrial/aortic diameters, the relative wall thickness and arterial vessels diameters did not change significantly throughout the pregnancy. The ratio interventricular septum/posterior wall thickness was 1.14 +/- 0.36 and ratio of 1.5 or greater was found in 14.5% of the fetal normal heart. The ratio left atrial/aortic diameter was 1.32 +/- 0.21 and left atrium was significantly greater than aorta (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Isolation of the Left Subclavian Artery in D-Transposition of the Great Arteries with Right Aortic Arch

Abnormal branching of the aorta associated with the right aortic arch (RAA) has been reported as isolation of left subclavian artery (ILSA), isolation of left common carotid artery, isolation of brachiocephalic artery. ILSA is a rare aortic branch anomaly that originates in the left subclavian artery from the pulmonary artery via ductus arteriosus. Several reports have described ILSA associated with 22q11.2 deletion syndrome and tetralogy of Fallot. Here, we present a very unusual case of RAA with ILSA associated with D-transposition of the great arteries and inferior vena cava interrupted with azygos continuation.     

The lungs and platelet production

Several studies have suggested that thrombopoiesis may occur in the lungs. To investigate the role of the lungs in platelet production, we measured automated platelet parameters in blood from the pulmonary artery and the radial artery (n=125) or aorta (n=26) in patients undergoing aorto-coronary bypass. No significant differences were found between pulmonary and radial arterial blood with regard to platelet count (192.132 +/- 46.250 vs. 192.004 +/- 46.294 x 10(9)/l), mean platelet volume (11.03 +/- 1.04 vs. 11.03 +/- 1.03 fl), plateletcrit (0.212 +/- 0.051 vs. 0.212 +/- 0.051 x 10(-2)), platelet distribution width (14.48 +/- 2.16 vs. 14.47 +/- 2.08 fl) and platelet-large cell ratio (0.350 +/- 0.076 vs. 0.351 +/- 0.078). Similar results were obtained in comparisons between pulmonary arterial and aortic blood. A coefficient of linear correlation of 0.98 was found between the pulmonary and radial arterial and aortic platelet counts. These findings suggest that the platelet population entering the lungs was the same as the platelet population leaving them. Our results do not therefore support the theory of pulmonary platelet production.     

Determinants of survival following repair of interrupted aortic arch in infancy.

Between January 1971 and March 1987, surgery was performed in 26 infants with interrupted aortic arch. At operation the 14 boys and 12 girls weighted between 1.71 and 4.23 kg (mean +/- SD = 3.1 +/- 0.63 kg) and ranged in age from 2 to 90 days (13 +/- 18 days). The interruption was distal to the left subclavian artery in 4 (15%), between the left carotid and subclavian arteries in 20 (77%) and between the brachiocephalic (innominate) and left carotid arteries in 2 (8%). Associated complex cardiac lesions in 8 patients included complete transposition (2), common arterial trunk (2), aortopulmonary window (2), double inlet left ventricle (1) and tricuspid atresia (1). The remaining patients had an isolated ventricular septal defect. The arch was reconstructed with a prosthetic conduit in 14 patients; by a direct anastomosis in 6; using the subclavian artery in 3; and with the pulmonary trunk and the arterial duct in 2. Twenty patients (77%) underwent palliative surgery as the first stage of management, and banding of the pulmonary trunk was also performed in 16 of these. Five patients (19%) underwent primary complete repair of the interruption and intracardiac anomalies. One patient (4%) died soon after thoracotomy for palliative surgery. Of the 15 (57%, 70% confidence limits CL = 46-69%) early deaths, 7 occurred in patients with complex associated defects and 4 occurred when single stage repair was attempted. Survival following first-stage palliative surgery for arch interruption with isolated ventricular septal defect was 64% (9/14) [70% CL = 47-79%]. All of these patients subsequently underwent complete repair. Chi-squared and t-tests showed the year of operation and the type of operation (two-stage repair) to be associated with improved survival. It is concluded that a two-stage repair of interrupted aortic arch offers a reasonable alternative to primary complete correction and will lead to satisfactory subsequent repair in most cases.     

Hemodynamics of the Mueller maneuver in man: right and left heart micromanometry and Doppler echocardiography

Ten subjects with normal hemodynamics were studied during elective cardiac catheterization with right and left heart multisensor micromanometry to assess hemodynamic responses to the Mueller maneuver. Simultaneous right and left circulatory hemodynamics and left ventricular, pulmonary arterial, and aortic pressures were recorded, in addition to pulmonary arterial and aortic flow velocities. Steady-state cardiac outputs were determined by thermal dilution. Aortic systolic and mean pressures were not significantly changed during the Mueller maneuver, in contrast to a lower diastolic (p = .019) and higher pulse pressure (p = .016). Mean right atrial pressure (+/- SE) decreased from 7 +/- 1 to -17 +/- 4 mm Hg (p = .0002) and the right atrial "x" descent was markedly accentuated. Left ventricular end-diastolic pressure decreased from 12 +/- 4 to -3 +/- 13 mm Hg (p = .0025). Systemic vascular resistance and left ventricular peak positive dP/dt were increased during the Mueller maneuver (p less than .02), cardiac output and stroke volume were reduced (p less than .05), and there was no significant change in heart rate. Right and left peak flow velocities showed a trend toward a bilateral decrease (right, p = .054; left, p greater than .1), and times to peak flow velocity were increased in the pulmonary artery (p = .007) and reduced in the aortic root (p = .03). Normal subjects were studied separately by pulsed Doppler echocardiography. During the sustained Mueller maneuver, the internal jugular and right ventricular dimensions decreased, and superior vena cava Doppler flow was reduced.(ABSTRACT TRUNCATED AT 250 WORDS)     

Aortic arch surgery using moderate systemic hypothermia and antegrade cerebral perfusion via the right subclavian artery

BACKGROUND: Surgery of the aortic arch avoiding profound systemic hypothermia and using antegrade or retrograde cerebral perfusion has recently been popularized. This usually renders the CPB and surgical field set-up more complex. We propose a simple method achieving a similar effect. METHODS: During a 6-month period, 7 patients (median age 72 years) underwent surgery involving the aortic arch with cannulation of the right subclavian artery for arterial return. There were 6 acute type A dissections and one ascending aorta and arch aneurysm. After commencing CPB, the ascending aorta was clamped and reconstruction of aortic valve and root were initiated. Patients were cooled to a tympanic temperature of 25 - 27 degrees C. CPB was then stopped, and the arch was opened and inspected from inside. While resuming arterial perfusion via the right subclavian artery, the arch branches were clamped sequentially from right to left under observation for back flow. Bilateral radial artery pressure and temporal transcutaneous oxygen saturation were always monitored. RESULTS: In all cases, the aortic valve was spared using remodeling and resuspension techniques. 2 complete arch, 2 partial arch and 3 proximal arch replacements were performed. Mean times were 183 (113 - 321) minutes for CPB and 120 (67 - 213) minutes for aortic cross-clamping. Maximal systemic circulatory arrest time was 82 min. One patient died in the hospital due to MRSA sepsis with a normal CCT scan. All others were discharged in good condition. CONCLUSION: The initial experience with this simple technique of antegrade cerebral perfusion avoiding profound systemic hypothermia and the possible disadvantages of femoral artery cannulation appears promising.     

Complete repair of the interrupted aortic arch by an anterior approach. Apropos of 9 cases

Interrupted aortic arch is a duct-dependent heart disease, and this is why the use of prostaglandins E, which keep the ductus arteriosus open to feed the descending aorta, has transformed its formerly sombre prognosis. The authors report the cases of 9 neonates and infants presenting with interrupted aortic arch associated with ventricular septal defect who underwent total repair of the malformations under extracorporeal circulation. Five children were less than 10 years' old. The aortic lesions were of type A in 2 cases (interruption distal to the left subclavian artery) and of type B in 7 cases (interruption between the left carotid and subclavian arteries). In the second group the lesions were of type B1 in 5 cases (without retro-oesophageal right subclavian artery) and of type B2 in 2 cases (right retro-oesophageal artery distal to the interruption). There was one death (11 p. 100). So far, no child has been reoperated upon for residual aortic obstruction or reopened ventricular septal defect. This technique of total repair in one stage, with closure of the ventricular septal defect, seems to be preferable to the two-stage technique in which stage one includes, in addition to aortic arch repair, cerclage of the pulmonary artery, a procedure with numerous disadvantages and a higher overall mortality rate.     

Prenatal diagnosis of left-sided aortic arch,right descending aorta and right-sided ductus arteriosus associated with anomalous origin of left pulmonary artery from ascending aorta

Left-sided aortic arch (LAA), right descending aorta (rDAo), and right-sided ductus arteriosus (RDA) constitute a rare aortic arch anomaly. Moreover, anomalous origin of the pulmonary artery from the ascending aorta, especially that of the left pulmonary artery, is also a rare anomaly of the pulmonary artery branches. Because of the presence of the ductus arteriosus, prenatal ultrasound is an optimal diagnostic tool for the LAA with rDAo. Four-dimensional color Doppler can clearly demonstrate the spatial relationship between the LAA, rDAo, and RDA and the anomalous origin of the left pulmonary artery from the ascending aorta.     

Dependence of blood flow in human aorto-coronary bypass grafts on the extravascular resistance (author's transl)]

As has been shown in a large number of animal experiments, there is a marked difference between the systolic-to-diastolic flow ratios of the right coronary artery and the left. We examined these ratios in 107 patients who were undergoing aorto-coronary bypass surgery as treatment for coronary artery disease. After cessation of cardio-pulmonary bypass, the blood flow was recorded electromagnetically in a total of 126 venous grafts to the right or to the branches of the left coronary arteries. From these tracings, the following magnitudes were calculated: coronary stroke flow per heart beat, systolic and diastolic stroke flows, mean flow, systolic and diastolic flows. The ratio of the systolic to the diastolic stroke flow was 0.30 +/- 0.17 for the branches of the left coronary artery (n = 79) and 0.61 +/- 0.30 for the right coronary artery (n = 47). The ratio of systolic to diastolic flow was found to be 0.46 +/- 0.25 (branches of the left coronary artery) and 1.01 +/- 0.62 (right coronary artery), respectively. All these values differ statistically on a probability level of p less than 0.001. In principle, our results agree with those of canine experiments. The considerable variation of the individual values of the systolic-to-diastolic flow ratios can be explained by the following: 1. the variability of the pattern of coronary blood supply in man; 2. the actual right and left ventricular pressures; 3. the extent of stenoses present; 4. the degree of myocardial impairment due to ischemia. These factors combined determine the actual value of the extravascular (myocardial) component of the peripheral coronary resistance, which is most effective during systole.     

Intermediate-term clinical and hemodynamic results of the neonatal arterial switch operation for complete transposition of the great arteries.

We prospectively evaluated 49 consecutive hospital survivors of the arterial switch operation for complete transposition and intact ventricular septum by clinical examination, echocardiography, cardiac catheterization, 12-lead and 24-h Holter ECG. The mean length of follow-up was 40 +/- 18 months. Forty-six children are clinically asymptomatic without medication, 2 died due to coronary related left ventricular dysfunction 3 and 12 months after surgery, and 1 required reoperation because of severe bilateral pulmonary branch stenoses. Except for this case, cardiac catheterization (n = 23) revealed a mean gradient of only 17 +/- 8 mmHg between the right ventricle and distal pulmonary arteries. Left ventricular end-diastolic volume was within normal limits except for 2 cases with volumes slightly below normal, the mean ejection fraction was 78 +/- 5%, and end-diastolic and end-systolic ventricular shapes were normal. The mean cardiac index was 4.14 +/- 0.69 l/min/m2. Left ventricular end-systolic wall stress to velocity of fiber shortening relation was normal in all cases examined (n = 15), indicating normal myocardial contractility. Significant neoaortic valve insufficiency was never observed despite considerably enlarged aortic roots. Twenty-four-hour Holter ECG records (n = 46) provided no evidence of serious atrial arrhythmias, especially sinus node dysfunction. These encouraging intermediate-term results make the arterial switch operation the treatment of choice at present, for neonates with simple transposition.     

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.