Juxtaductal aortic coarctation. Analysis of 84 patients studied hemodynamically, angiographically, and morphologically after age 1 year

Characteristics of Adults Having Aortic Valve Replacement for Pure Aortic Regurgitation Involving a Congenitally Bicuspid Aortic Valve Unaffected by Infective Endocarditis or Aortic Dissection

Few reports have appeared describing patients with a purely regurgitant congenitally bicuspid aortic valve (BAV) unassociated with active or healed infective endocarditis or with acute or healed aortic dissection. This report describes a large group of such patients who had replacement of the purely regurgitant BAV with or without concomitant resection of the ascending aorta. Operatively excised purely regurgitant BAVs were examined and then their clinical records were examined to confirm that the valves indeed were purely regurgitant. The patients were aged 21 to 86 years (median 50). Of the 133 patients, 114 (86%) were men. The degree of aortic regurgitation (AR) ranged from 1+ to 4+/4+. Of the 133 patients, 52 (39%) had simultaneous resection of the ascending aorta, its frequency varying inversely with the degree of AR. Histologic study of sections of the operatively excised aortas disclosed that 28 (54%) had a normal or nearly normal aorta (0-1+ loss of medial elastic fibers) and that 24 (46%) had an abnormal loss (grade 2+ -4+/4+). In conclusion, the congenitally BAV, unassociated with either infective endocarditis or aortic dissection, is a common cause of pure AR in adults in the Western World undergoing AVR for AR. About half the patients had a dilated ascending aorta and those resected were histologically abnormal half the time. Why one BAV becomes stenotic, another purely regurgitant, another the site of infective endocarditis, and another functions normally for an entire lifetime remains unclear.

Two-dimensional echocardiographic predictors of coarctation of the aorta

BACKGROUND

Coarctation of the aorta is a very common congenital heart malformation. It is frequently associated with other abnormalities. Echocardiography is the diagnostic modality for congenital heart disease. The carotid-subclavian artery index and the isthmus/descending aorta index were proposed for establishing the diagnosis of coarctation of the aorta.

OBJECTIVES

The objectives were to evaluate such indexes and to look for other echocardiographic predictors of coarctation of the aorta.

METHOD

Echocardiography was reviewed for infants with coarctation of the aorta, as well as a control group, using the Echo PAC Dimension. Standard measurements were obtained from different sites of the aortic arch.

RESULTS

A total of 31 infants 3 months or less with coarctation of the aorta and 50 infants with no coarctation of the aorta were reviewed. Abnormal aortic valve was present in 65% of those with coarctation of the aorta. The diameters of the proximal and the distal transverse aortic arch were smaller in the coarctation of the aorta group. The distance between the aortic arch branches was longer in the coarctation of the aorta group. Apart from the ratio between distance 2 and the ascending aorta, other ratios/indexes were smaller in the coarctation of the aorta group than in the control group.

CONCLUSION

The presence of abnormal aortic valve, a carotid subclavian index <1.1, I/AAo ratio <0.53, and DTA/AAo ratio <0.6 suggest the presence of coarctation of the aorta. Neonates with large patent ductus arteriosus and any of these findings need close observation until the patent ductus arteriosus closes. If the arch is difficult to assess by two-dimensional echocardiography, the patient may need further imaging to rule out coarctation of the aorta.

Natural history of adults with congenitally malformed aortic valves (unicuspid or bicuspid)

Appreciation of the frequency of the congenitally malformed aortic valve has come about during the last 50 years, a period during which aortic valve replacement became a predictably successful operation. Study of patients at necropsy with either a congenitally unicuspid (1 true commissure) or bicuspid (2 true commissures) valve in whom no aortic valve operation has been performed has not been conducted during these 50 years, to our knowledge. We studied 218 patients at necropsy with congenitally malformed aortic valves: 28 (13%) had a unicuspid valve and 190 (87%), a bicuspid valve. Their ages at death ranged from 21 to 89 years (mean, 55 yr), and 80% were men. Of the 218 adults, the aortic valve functioned normally during life in 54 (25%) and abnormally in 164 (75%): aortic stenosis in 142 (65%), pure aortic regurgitation without superimposed infective endocarditis (IE) in 2 (1%), and IE superimposed on a previously normally functioning aortic valve in 20 (9%). IE occurred in a total of 31 (14%) of the 218 patients: involving a previously normally functioning valve in 20 (65%) and a previously stenotic valve in 11 (35%). Of the 218 patients, at least 141 (65%) died as a consequence of aortic valve disease (124 patients) or ascending aortic tears with or without dissection (17 patients). An estimated 1% of the population, maybe higher in men, has a congenitally malformed aortic valve. Data from this study suggest that about 75% of them will develop a major complication. Conversely, and encouragingly, about 25% will go through life without a complication.

Presence of a congenitally bicuspid aortic valve among patients having combined mitral and aortic valve replacement

Although bicuspid aortic valve occurs in an estimated 1% of adults and mitral valve prolapse in an estimated 5% of adults, occurrence of the 2 in the same patient is infrequent. During examination of operatively excised aortic and mitral valves because of dysfunction (stenosis and/or regurgitation), we encountered 16 patients who had congenitally bicuspid aortic valves associated with various types of dysfunctioning mitral valves. Eleven of the 16 patients had aortic stenosis (AS): 5 of them also had mitral stenosis, of rheumatic origin in 4 and secondary to mitral annular calcium in 1; the other 6 with aortic stenosis had pure mitral regurgitation (MR) secondary to mitral valve prolapse in 3, to ischemia in 2, and to unclear origin in 1. Of the 5 patients with pure aortic regurgitation, each also had pure mitral regurgitation: in 1 secondary to mitral valve prolapse and in 4 secondary to infective endocarditis. In conclusion, various types of mitral dysfunction severe enough to warrant mitral valve replacement occur in patients with bicuspid aortic valves. A proper search for mitral valve dysfunction in patients with bicuspid aortic valves appears warranted.

Balloon angioplasty for native coarctation of the aorta in neonates and infants with congestive heart failure

BACKGROUND

Balloon angioplasty (BA) is an alternative to surgical repair for coarctation of the aorta (CoA) in children. However, its role in the treatment of native CoA in neonates and infants remains controversial. The purpose of this study was to report the midterm outcomes of BA for native CoA in neonates and infants with congestive heart failure (CHF).

METHODS

Between July 2000 and March 2007, 18 neonates and infants with native CoA and CHF who underwent BA were enrolled. Patients without recoarctation were designated as group A, while those with recoarctation or CHF were designated as group B. The clinical presentations, laboratory data, and outcomes were compared between groups.

RESULTS

There were 10 patients in group A and eight in group B. The mean age was 2.8 +/- 3.1 months (range, 0.7-11 months). Mean body weight was 4.0 +/- 1.9 kg (range, 2.1-8.0kg). CHF improved markedly in all patients immediately after BA, with a reduction in systolic pressure gradient from 36.4 +/- 12.0 to 5.6 +/- 6.0 mmHg (p < 0.001). The recoarctation rate was 44% (8/18). The risk factors for restenosis were post-BA systolic pressure gradient >10 mmHg (p = 0.007) and CoA diameter <3 mm (p = 0.013).

CONCLUSIONS

The outcomes of BA for native CoA in neonates and infants with CHF remain poor. The incidence of recoarctation is high in neonates and patients whose post-BA systolic pressure gradient is >10 mmHg or whose CoA diameter is <3 mm.

Validation of two echocardiographic indexes to improve the diagnosis of complex coarctations

OBJECTIVES

Coarctation of the aorta is one of the most common congenital heart defects. Its diagnosis may be difficult in the presence of a patent ductus arteriosus, of other complex defects or of a poor echocardiographic window. We sought to demonstrate that the carotid-subclavian artery index (CSA index) and the isthmus-descending aorta ratio (I/D ratio), two recently described echocardiographic indexes, are effective in detection of isolated and complex aortic coarctations in children younger and older than 3 months of age. The CSA index is the ratio of the distal aortic arch diameter to the distance between the left carotid artery and the left subclavian artery. It is highly suggestive of a coarctation when it is <1.5. The I/D ratio defined as the diameter of the isthmus to the diameter of the descending aorta, suggests an aortic coarctation when it is less than 0.64.

METHODS

This is a retrospective cohort study in a tertiary care children's hospital. Review of all echocardiograms in children aged 0-18 years with a diagnosis of coarctation seen at the author's institution between 1996 and 2006. An age- and sex-matched control group without coarctation was constituted. Offline echocardiographic measurements of the aortic arch were performed in order to calculate the CSA index and I/D ratio.

RESULTS

Sixty-eight patients were included in the coarctation group, 24 in the control group. Patients with coarctation had a significantly lower CSA index (0.84+/-0.39 vs 2.65+/-0.82, p<0.0001) and I/D ratio (0.58+/-0.18 vs 0.98+/-0.19, p<0.0001) than patients in the control group. Associated cardiac defects and age of the child did not significantly alter the CSA index or the I/D ratio.

CONCLUSIONS

A CSA index less than 1.5 is highly suggestive of coarctation independent of age and of the presence of other cardiac defects. I/D ratio alone is less specific than CSA alone at any age and for any associated cardiac lesion. The association of both indexes improves sensitivity and permits diagnosis of coarctation in all patients based solely on a bedside echocardiographic measurement.

Cardiac transplantation and aortic coarctation repair in severe heart failure

A 37-year-old man presented with severe dilated cardiomyopathy secondary to occult aortic coarctation. He was successfully managed with combined orthotopic heart transplantation and aortic coarctation repair.

Coarctation of the aorta: pre and postoperative evaluation with MRI and MR angiography; correlation with echocardiography and surgery

AIMS

To compare MRI and MRA with Doppler-echocardiography (DE) in native and postoperative aortic coarctation, define the best MR protocol for its evaluation, compare MR with surgical findings in native coarctation.

MATERIALS AND METHODS

136 MR studies were performed in 121 patients divided in two groups: Group I, 55 preoperative; group II, 81 postoperative. In group I, all had DE and surgery was performed in 35 cases. In group II, DE was available for comparison in 71 cases. MR study comprised: spin-echo, cine, velocity-encoded cine (VEC) sequences and 3D contrast-enhanced MRA.

RESULTS

In group I, diagnosis of coarctation was made by DE in 33 cases and suspicion of coarctation and/or aortic arch hypoplasia in 18 cases. Aortic arch was not well demonstrated in 3 cases and DE missed one case. There was a close correlation between VEC MRI and Doppler gradient estimates across the coarctation, between MRI aortic arch diameters and surgery but a poor correlation in isthmic measurements. In group II, DE detected a normal isthmic region in 31 out of 35 cases. Postoperative anomalies (recoarctation, aortic arch hypoplasia, kinking, pseudoaneurysm) were not demonstrated with DE in 50% of cases.

CONCLUSIONS

MRI is superior to DE for pre and post-treatment evaluation of aortic coarctation. An optimal MR protocol is proposed. Internal measurement of the narrowing does not correspond to the external aspect of the surgical narrowing.

Percutaneous stenting of anastomotic stenoses in tubular interposition grafts used to repair aortic coarctation in adults

Stenting is the usual treatment for recoarctation following resection with direct end-to-end anastomosis. We describe for the first time stenting to relieve anastomotic stenoses in tubular interposition grafts, which are used to repair approximately 10% of coarctations. Success in these two adults expands further the spectrum of large conduits that may be relieved of stenosis by stenting.

Reduced left ventricular dimension and normalized atrial natriuretic hormone level after repair of aortic coarctation in an adult

Although unusual in the older patient, coarctation of the aorta can be an occult cause of cardiomyopathy. This report describes a 53-year-old man with new-onset heart failure symptoms, global left ventricular (LV) dysfunction, and underlying aortic coarctation. Surgical correction resulted in reduced LV size, resolution of symptoms, and normalization of atrial natriuretic hormone levels.

Nonneoplastic diseases of aorta and pulmonary trunk--Part IV

This five-part review focuses on selected nonneoplastic diseases of the aorta and pulmonary trunk. Because many more diseases affect the aorta compared with the pulmonary trunk and right and left main pulmonary arteries, most of this review will be devoted to disorders of the aorta. Part IV of the series discusses cystic medial degeneration, trauma, and congenital diseases of the aorta.

Cardiac surgery for grown-up congenital heart patients: survey of 307 consecutive operations from 1991 to 1994

The cardiac surgery performed from 1991 to 1994 in a unit dedicated specifically for grown-up congenital heart (GUCH) patients was reviewed to determine the frequency of various procedures, incidence of first and reoperations, early mortality, and its determinants. The 295 patients, aged 16 to 77 years (31 +/- 13), had 307 operations. First operations (n = 128, 42%) were most commonly for closure of atrial septal defect (n = 40), aortic valve replacement (n = 31) or repair of aortic coarctation (n = 14). Reoperations were more frequent (n = 179, 58%) and divided among first corrective repair (n = 49), reoperation after corrective repair (n = 115), and further palliation (n = 15). First corrective surgery was mainly for aortic valve disease (n = 17), Fallot (n = 7), and lesions needing a Fontan procedure (n = 5). Reoperations after corrective repair were needed for aortic valve disease (n = 43), right-sided conduit (n = 30), or recoarctation (n = 11). Early mortality was influenced by presence of central cyanosis (9 of 49, 18% in cyanotic patients; 12 of 258, 5% in acyanotic; p <0.001), increased number of previous operations (0 = 4%, 1 = 7%, 2 = 11%, >2 = 13%; p = 0.003), and increasing age of patients. Cyanotic patients had more serious postoperative complications: pleural and pericardial effusions, severe bleeding, renal insufficiency, and sepsis, and their hospital stay was longer compared with acyanotic patients (20 +/- 17 vs 11 +/- 8 days; p <0.001). In GUCH patients, reoperations cause the largest demand on cardiac surgical services. Increased survival of patients with complex cardiovascular malformations brings difficult challenges not only to cardiologists but also to cardiovascular surgeons. There is a need to provide continued highly specialized care. Resources, patients, and funding should be concentrated in a few designated centers.

Severe Aortic Coarctation in an Adult Without Left Ventricular Hypertrophy Nor Overt Collateral Channels

We describe an unusual case of periductal carctation of the aorta in a 40-year-old patient presenting to the echocardiography laboratory for evaluation of a heart murmur. Subsequent clinical history revealed easy fatigability, dyspnea on exertion, and hypertension. Despite a lack of left ventricular hypertrophy, aortic coarctation was suggested by echocardiography. It was later confirmed to be severe by multiple additional imaging modalities, despite an absence of overt collateral arterial channels. The importance of echocardiography in the diagnosis of coarctation of the aorta and the management of this complicated patient is discussed.

Secondary hypertension: evaluation and treatment

Most patients with hypertension in the United States have essential (primary) hypertension (95%), the cause of which is unknown. The remaining 5% of adults with hypertension have the secondary form of hypertension, the cause and pathophysiologic process of which are known. Internists and other primary care physicians refer to this as treatable or curable hypertension, because the hypertension can be managed or even controlled with medications. Similarly, the condition is called surgical hypertension by surgeons in the belief that once the cause is determined and identified, surgical intervention will result in cure of hypertension. Secondary causes of hypertension include renal parenchymal disease, renovascular diseases, coarctation of the aorta, Cushing's syndrome, primary hyperaldosteronism, pheochromocytoma, hyperthyroidism, and hyperparathyroidism. Occasionally included in this category are alcohol- and oral contraceptive-induced hypertension and hypothyroidism, but these conditions are not discussed herein. The evaluation of secondary hypertension is of interest and can bring together different facets of anatomy, physiology, pharmacology, and radiology in the medical and surgical treatment of these disorders. Despite enthusiasm that can be generated in the evaluation of these conditions, evaluation can be expensive and should not be conducted for all patients with hypertension. Features that aid in the diagnosis of secondary hypertension include the following: 1. Onset of hypertension before the age of 20 or after the age of 50 years. The presence of hypertension at a young age may suggest coarctation of the aorta, fibromuscular dysplasia, or an endocrine disorder. Hypertension found for the first time after the age of 50 years may suggest the presence of renovascular hypertension caused by atherosclerosis. 2. Markedly elevated blood pressure or hypertension with severe end-organ damage, as in grade III or IV retinopathy. These findings suggest the presence of renovascular hypertension or pheochromocytoma. 3. Specific body habitus and ancillary physical findings. For example, truncal obesity and purple striae occur with hypercortisolism, and exophthalmos is associated with hyperthyroidism. 4. Resistant or refractory hypertension (poor response to medical therapy usually necessitating use of more than three antihypertensive medications from three different classes). 5. Specific biochemical test that suggest the existence of certain disorders, such as hypercalcemia in hyperparathyroidism, hyperglycemia in Cushing's syndrome and pheochromocytoma, and unprovoked hypokalemia with renin-producing tumors, primary hyperaldosteronism, or renin-mediated renovascular hypertension. 6. Other characteristics that may suggest secondary hypertension such as abdominal diastolic bruits (renovascular hypertension), decreased femoral pulses (coarctation of the aorta), or bitemporal hemianopias (Cushing's disease). A combination of a good history and physical examination, astute observation, and accurate interpretation of available data usually are helpful in the diagnosis of a specific causation.

Transesophageal echocardiographic assessment of aortic coarctation using color, flow-directed Doppler sampling

We report the use of color, flow-directed transesophageal Doppler in the evaluation of aortic coarctation. Transesophageal echocardiography (TEE) was used to define the aortic shelf in two adults with mild and moderate postductal coarctation, respectively. The color mosaic pattern aided in identification of the coarctation location and orifice diameter. Continuous wave and pulsed cursors were steered to provide sampling parallel to the color jet direction and gradients calculated by the modified Bernoulli formula, excluding prestenotic velocities. Measured pressure gradients were equivalent to those determined at catheterization. We conclude that color, flow-directed TEE Doppler sampling can aid in the identification and characterization of adult patients with aortic coarctation.

Noninvasive long-term follow-up after coarctation repair

Thirty patients operated on for aortic coarctation while less than 3 years of age underwent magnetic resonance imaging, digital subtraction angiography, and bicycle exercise testing 14 to 33 years (mean, 22 years) after operation. Diameters of the aorta at the site of the anastomosis, of the distal arch, and of the aorta at the level of the diaphragm were measured in the images. Blood pressures were obtained from the right arm and leg before and after exercise. Patients were divided into three groups according to blood pressure data: group I, resting gradient less than 30 mm Hg and exercise gradient less than 50 mm Hg; group II, resting gradient less than 30 mm Hg and exercise gradient greater than 50 mm Hg; and group III, resting gradient 30 mm Hg or greater. A control group underwent the same test. The frequency of hypertensive patients was greater in groups II (58%) and III (100%) than in group I (20%). The anastomosis/descending aorta ratio seen in digital subtraction angiograms was smaller in group II and III patients. Exercise blood pressure gradient correlated significantly (r = -0.48; p = 0.009) with anastomosis/descending aorta ratio in digital subtraction angiograms but not in magnetic resonance images. Twenty of 30 patients (67%) had a significant anatomic narrowing at the site of the anastomosis. Blood pressure data correlated with diameters measured in digital subtraction angiograms but not with diameters measured in magnetic resonance images.

Association of distal displacement of the left subclavian artery and coarctation of the aorta

Previously noted but undocumented observation of distal displacement of the left subclavian artery in patients with discrete coarctation of the aorta was verified by an objective two-dimensional echocardiographic method in 28 patients with aortic coarctation and in 43 control subjects. Relative position of brachiocephalic arteries to one another was evaluated by the ratio of the distance between the left common carotid and the left subclavian artery to the distance between the innominate and the left common carotid artery. Large distance between the left common carotid and the left subclavian artery was reflected by high value of the derived ratio. In neonates with aortic coarctation, the ratio was 1.69, SD +/- 0.66, compared to 1.04, SD +/- 0.40 in the control group. In older children this ratio was less discriminatory. We also observed that the left subclavian artery formed an acute angle (less than 90 degrees) with the proximal (upstream) segment of the aortic arch in infants with aortic coarctation. In all control infants, this angle was equal to or greater than 90 degrees. A corresponding necropsy study confirmed the echocardiographic findings. We conclude that distal displacement of the left subclavian artery is associated with coarctation of the aorta. It can be accurately visualized and objectively assessed by the two-dimensional echocardiographic technique proposed.

Accuracy of two-dimensional echocardiography in the diagnosis of aortic arch obstruction

To evaluate the predictive accuracy of two-dimensional echocardiography in the diagnosis of aortic arch obstruction, 540 consecutive patients aged 2 days to 15 years (mean 2 months) who underwent subsequent cardiac catheterization and angiography were prospectively studied. At angiography, 51 patients had aortic arch obstruction; of these, 35 had juxtaductal coarctation, 15 isthmic hypoplasia and 1 a type B interrupted aortic arch. The presence of arch obstruction was correctly identified with two-dimensional echocardiography in 45 of 51 patients with this condition (overall sensitivity 88%). Two-dimensional echocardiography clearly defined a juxtaductal coarctation in 33 of 35 patients and isthmic hypoplasia in 13 of 15 patients (sensitivity 94% and 73%, respectively). The form and type of interrupted aortic arch were clearly distinguished from other forms and types of arch obstruction. Among the 489 patients without aortic arch obstruction, two-dimensional echocardiography wrongly diagnosed the presence of such obstruction in 9 patients (overall specificity 98%). Forty-six (92%) of the 51 patients had at least one associated intracardiac abnormality. Twenty-two (44%) had a ventricular septal defect, 21 (42%) a bicuspid aortic valve and 4 (18%) subaortic stenosis. Five patients had complex congenital cardiac malformations. All associated abnormalities were prospectively identified with two-dimensional echocardiography. Thus, two-dimensional echocardiography is highly specific in diagnosing aortic arch obstruction. It is less sensitive for the diagnosis of isthmic hypoplasia in the neonatal period.

Exercise testing after surgical repair of coarctation of the aorta

After repair of coarctation, exercise testing was performed in 20 patients with an isolated coarctation (group I) and in 26 with additional congenital cardiac malformations (group II). Ages at time of operation were significantly different in both groups (7.9 +/- 6.0 years in group I; 4.6 +/- 3.8 years in group II; p less than or equal to 0.01). Simultaneous blood pressures were obtained from upper and lower limbs at rest and after exercise. There was no significant difference regarding the systolic blood pressures at rest (122.5 +/- 15.6 mmHg in group I versus 119 +/- 15.8 mmHg in group II). Seven (14%) of the patients were hypertensive; five of them had blood pressure gradients between arms and legs of 15-45 mmHg. But the gradients at rest were found to be significantly different in both groups (9.0 +/- 10.5 mmHg in group I; 18.5 +/- 16.1 mmHg in group II; p less than or equal to 0.05). Six patients, all in group II, had gradients greater than or equal to 30 mmHg at rest. After exercise there were no significant differences in systolic blood pressure and gradients in both groups. Values for blood pressures and gradients at rest and after exercise showed a positive correlation (blood pressure r = 0.76, p less than or equal to 0.001; gradient r = 0.44, p less than or equal to 0.01). Thus exercise testing can provide valuable information about blood pressure and gradient changes during physical activity, but angiography is required to reveal restenosis or residual stenosis.

Coarctation and other obstructive aortic arch anomalies: their relationship to the ductus arteriosus

Forty-three specimens with an obstructive aortic arch anomaly, obtained from infants that had died under the age of one year, were studied to establish the relationship between the arch anomalies and the ductus arteriosus. All specimens were studied morphologically. Twenty of the 43 were also studied histologically. The morphological part of the study included measurements of all the segments of the aortic arch and establishment of the localisation of any associated coarctation. The specimens were divided according to the appearance of the isthmus. The isthmus was not present in 4, was atretic in 2, hypoplastic in 19 and had a normal diameter in 18 cases. In all cases, except 5 (2 with atresia and 3 with hypoplasia of the isthmus) there was an associated coarctation. The majority of the coarctations (28) was located preductally. All such preductal coarctations had ductal tissue in the obstructing ridge. There were 5 paraductal coarctations. Of these, two also had ductal tissue in the ridge. The distribution of the ductal tissue among the two types of coarctation suggested a spectrum of anomalies rather than two completely different entities. The patterns of the aortic arches appeared predictive for the type of coarctation present. The arches that tapered normally towards the isthmus either presented with a preductal coarctation (20 cases) or without a coarctation (3 cases). All 4 specimens in which the isthmus was lacking also had a preductal coarctation. The 5 paraductal coarctations were found in arches that showed a "reverse" pattern, tapering towards the brachiocephalic arteries. All the preductal coarctations contained ductal tissue whereas only 2 of the 5 paraductal coarctations had ductal tissue in the obstructing ridge. It is concluded that careful evaluation of all the segments of the aortic arch may be helpful in the clinical evaluation of infants with an obstructive aortic arch anomaly.

Persistent ventricular adaptations in postoperative coarctation of the aorta

To evaluate ventricular performance and myocardial contractility after surgical correction of congenital coarctation of the aorta, we studied 25 patients (16 men and 9 women, mean age 26.1 years [range 19 to 34]), an average of 10.6 years (range 2 to 25) after repair. Radionuclide ventriculography at rest and exercise and digitized, quantitative two-dimensional echocardiography were performed. Data from derived, high resolution time-activity curves by radionuclide ventriculography, combined with noninvasive hemodynamic/ventricular volume data, were compared with values in an age- and sex-matched normal population. Despite essentially identical baseline and exercise hemodynamics, postoperative coarctation subjects demonstrated enhanced ventricular contraction, as determined by the peak ejection rate at rest (-3.79 versus -3.20 stroke volume/s, p less than 0.01) and exercise (-3.00 versus -2.90 stroke volume/s, p = NS), and overall ejection fraction at rest (56.4 versus 48.0%, p less than 0.01) and exercise (70.8 versus 59.3%, p less than 0.01). An intrinsic activation-contraction delay was observed, as illustrated by a prolonged time to peak ejection rate at rest (27.7 versus 21.5% of the RR interval, p less than 0.01) and exercise (28.4 versus 21.2% of the RR interval, p less than 0.01), and total systolic time at rest (50.2 versus 43.4% of the RR interval, p less than 0.01) and exercise (56.8 versus 50.4% of the RR interval, p less than 0.01). Although left ventricular meridinal wall stress was statistically indistinguishable (62 versus 74 mm Hg/mm2, p = NS), intrinsic myocardial contractility, as assessed by the peak systolic pressure/volume ratio, was increased in the postoperative coarctation group (1.88 versus 2.87 mm Hg/ml, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Interruption of the aortic arch and coarctation of the aorta: pathogenetic relations

The pathologic anatomic features and associated cardiac anomalies of 63 cases of interruption of the aortic arch (IAA) type A (54 reported and 9 observed) and 145 cases of type B (124 reported and 21 observed) were analyzed and compared with those seen in 57 autopsy cases of infant coarctation of the aorta (CA). There was no significant sex predominance within the 3 groups and the prognosis without surgery was uniformly poor. Ventricular septal defect was much more common in IAA type B than in type A or CA. Anomalous origin of the subclavian artery and DiGeorge syndrome were commonly associated with IAA type B but were rare in type A and CA. Transposition of the great arteries and double-inlet left ventricle are less common in IAA type B than in types A and CA. On the basis of these findings and the observation by Le Lièvre and Le Douarin that neural crest cells contribute significantly to the formation of the visceral arch system and associated organs, we postulate that IAA type B may be a manifestation of a developmental error involving the neural crest, as is the DiGeorge syndrome. We believe IAA type A and CA to be closely related anomalies that may be prenatally acquired and pathogenetically distinct from IAA type B.