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PubMedDate not supplied

The syndrome of absent pulmonary valve and ventricular septal defect--anatomical features and embryological implications.

Four cases of absent pulmonary valve in combination with ventricular septal defect are reported. In this syndrome hypo- and dysplasia of the pulmonary valve is constantly associated with a big ventricular septal defect, formation of a huge pulmonary artery aneurysm and absence of the ductus arteriosus. Presence or absence of a right ventricular outflow tract obstruction is the criteria for classification into two forms. Absence of the pulmonary valve, right ventricular outflow tract obstruction and a malalignment-type ventricular septal defect produced by a conotruncal malseptation process represent the primary complex of malformations. Consecutive intrauterine cardiac failure is most probably prevented by prenatal closure of the ductus arteriosus. Pulmonary artery aneurysm and also dilatation of the right ventricular outflow tract as well as a whole lot of other coexisting deformities can be explained by a cascade of hemodynamical sequelae started by this ductus closure in utero. An embryological scheme explaining the genesis of this syndrome is derived from a morphological analysis of the constituting incoherent-appearing anatomical features.

Angiocardiography↗
PubMed1988

Variable arginine vasopressin levels in neonatal congestive heart failure.

Arginine vasopressin levels in 17 neonates with cardiac disease were compared with control levels in 10 healthy newborn infants. Infants with congestive heart failure who were free of left ventricular outflow tract obstruction had a mean level of 80 +/- 18 pg/ml, which was significantly greater than the mean control level (p less than 0.001). Infants with congestive heart failure and left ventricular outflow tract obstruction had a mean vasopressin level of 3 +/- 0.7 pg/ml, which was lower than the mean control level of 6 +/- 0.7 pg/ml (p less than 0.05). The data suggest that impaired forward flow to high pressure sinoaortic and ventricular baroreceptors is necessary for vasopressin release in congestive heart failure. In left ventricular outflow tract obstruction with heart failure these receptors may be impaired or absent, leading to decreased vasopressin release. Low plasma arginine vasopressin may adversely affect circulatory homeostasis.

Acute Disease↗
PubMed1984

Accuracy of combined two-dimensional echocardiography and continuous wave Doppler recordings in the estimation of pressure gradient in right ventricular outlet obstruction.

Fifteen patients (median age 8.5 years) with fixed right ventricular outflow tract obstruction were evaluated by two-dimensional echocardiographically directed continuous wave Doppler ultrasound within 24 hours of cardiac catheterization. Pulmonary artery blood velocity measurements were determined from a real time spectral display of pulmonary artery flow profile and converted to pressure drop utilizing a modified Bernoulli equation. Use of both parasternal and subcostal imaging permitted more accurate detection of maximal flow velocity than did use of either approach alone. Gradients estimated from Doppler recordings correlated well with those measured at cardiac catheterization (correlation coefficient = 0.95, standard error of the estimate = 7.9 mm Hg) with a trend to slight underestimation of gradient in more severe obstruction. In three patients with combined valvular and subvalvular stenosis and one patient with right ventricular outlet obstruction due totally to a ventricular septal aneurysm, Doppler estimation of gradient provided an accurate assessment of total right ventricular-pulmonary artery gradient. Thus, continuous wave Doppler ultrasound combined with two-dimensional echocardiography provides a reliable noninvasive method of estimating pressure gradient in patients with right ventricular outflow tract obstruction.

Adolescent↗
PubMed1997

Ross-Konno procedure with interrupted aortic arch repair in a premature neonate.

A 1,700-g premature baby who presented with interrupted aortic arch type B, hypoplastic aortic annulus, severe subaortic stenosis, and large ventricular septal defect underwent successful surgical repair. A Ross-Konno operation was used to address the left ventricular outflow tract obstruction, hypoplastic aortic annulus, and ventricular septal defect. The interruption was repaired with a direct anastomosis.

Abnormalities, Multiple↗
PubMed1995

Extending the limits of the Ross procedure.

BACKGROUND: The potential for growth and the proven long-term durability of the native pulmonary valve make it ideal for replacement of the diseased aortic valve, especially in growing children. The use of the autologous pulmonary valve can be further extended to patients with complex left ventricular outflow tract obstruction and to neonates and infants. METHODS: Between June 1993 and May 1995, 35 patients underwent the Ross procedure at our center. Of these, 15 (43%) had complex left ventricular outflow tract obstruction and 7 (20%) were infants, including 3 neonates. The autologous pulmonary valve was implanted as a root replacement with coronary reimplantation in all patients. Additional left ventricular outflow tract procedures performed were ventricular myectomy in 7 patients and a Konno type aortoventriculoplasty in 11 patients. RESULTS: There was one early death in a patient with borderline hypoplastic left heart syndrome. At a median follow-up of 9 months (range, 0.2 to 22 months) there were no late deaths or reinterventions. The autologous pulmonary valve function was excellent, with 1 (2.8%) patient having moderate insufficiency. CONCLUSIONS: Autologous pulmonary valve is an excellent option for aortic valve replacement in all age groups. Its use can be readily extended to neonates, infants, and patients with complex left ventricular obstruction requiring additional left ventricular outflow tract procedures.

Adolescent↗
PubMed1997

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.

Cardiac Surgical Procedures↗
PubMed2004

The role of aortic translocation in the management of complex transposition of the great arteries.

The surgical management of transposition of the great arteries with a ventricular septal defect and left ventricular outflow tract obstruction still remains a significant challenge despite major advances in pediatric cardiovascular surgery. Almost four decades after its inception, the Rastelli procedure continues to be the standard surgical technique used in the management of these patients, despite less than optimal long-term results. Aortic translocation with biventricular outflow tract reconstruction is an alternative surgical technique that creates anatomically sound connections between the ventricles and their respective great arteries, which could result in better long-term outcomes. This technique is especially useful in patients with transposition of the great arteries/ventricular septal defect/left ventricular outflow tract obstruction who have an inlet or restrictive ventricular septal defect, a small right ventricle, a straddling atrioventricular valve, or an aberrant coronary artery crossing the right ventricular outflow tract.

Aorta↗
PubMed1997

[Intraventricular obstructions in dobutamine stress echocardiography: determinants of their development and clinical sequelae].

UNLABELLED: Dobutamine stress echocardiography (DSE) leads to strong hypercontraction, tachycardia, and peripheral vasodilatation. In previous studies systolic obstruction of the left ventricular outflow tract (LVOT) was observed as a result of these factors. To evaluate left ventricular function and morphology in patients (pts) with induced systolic LVOT obstruction, we used continuous wave (CW) doppler registrations in combination with quantitative 2-D-echocardiography in 100 pts during routinely performed DSE (5-40 micrograms/kg/min). In addition left ventricular wall thickness was measured. Symptoms were registered using a standardised questionnaire and cardiac arrhythmias were counted over a two minute interval at rest and during the maximal heart rate of each patient. During DSE dynamic flow acceleration with late systolic peak velocity above 2 m/second (s) was considered to represent LVOT obstruction in pts with normal flow profiles in the LVOT before infusion of dobutamine. For invasive studies pts were investigated with femoral catheterisation by the method of Judkins. A greater than 50% stenosis was judged to be significant. RESULTS: Examinations in 73 pts provided data of sufficient quality for echocardiographic and Doppler sonographic evaluations. 39 pts, 26 men, 13 women, mean age 64 +/- 8 years, developed late systolic flow velocities above 2 m/s and therefore formed the obstructive group (grp A). Grp B consisted of 34 pts, 26 men and 8 women, mean age 66 +/- 10 years, who showed normal time velocity integrals during DSE. In 41 pts invasive data provided information concerning the existence and severity of coronary artery disease. There were no significant differences in the increase of heart rate, the product of maximal systolic blood pressure and maximal heart rate or the percentage of pts, who reached their age corrected submaximal heart rate during DSE. Obstructive pts (group A) showed late systolic dynamic acceleration of systolic flow with a mean maximal speed of 315.4 +/- 139.8 cm/s, which peaked 0.12 +/- 0.04 s after the R-wave. From the velocities we calculated a mean pressure gradient of 47.5 +/- 39.7 mm Hg using the modified Bernoulli equation. Group B patients showed lower and earlier maximal speeds with a mean value of 158.2 +/- 37.6 cm/s, 0.09 +/- 0.04 s after the R-wave, corresponding to a pressure gradient of 10.6 +/- 4.9 mm Hg (p < 0.001). Ejection fractions were higher (p < 0.001) before the test in grp A: 68.2 +/- 8% compared to 55.7 +/- 10.4% in B. This difference increased during peak stress: 74.1 +/- 7.7% compared to 59.5 +/- 12.8%. End diastolic (EDVI) and end systolic volume indexes (ESVI) were lower in grp A (p < 0.001). During DSE, the decrease in ESVI was somewhat stronger for pts in grp A. Left ventricular hypertrophy was more often seen with obstruction. Septal thickness was increased in A: 1.45 +/- 0.34 cm compared to 1.13 +/- 0.27 cm in B (p < 0.001). Left ventricular posterior wall measured 1.03 +/- 0.28 cm in A and 0.83 +/- 0.23 cm in B (p < 0.01). 27 pts in grp B and only 9 in grp A had a history of previous myocardial infarction. Showing no difference at rest, wall motion score indexes raised under DSE in both groups and developed significantly higher scores in grp B at peak stress: 1.30 (1.0-1.90) compared to 1.18 (1.0-1.75) in A. We observed typical chest pain more often in grp B. Unspecific symptoms and arrhythmogenic complications were not statistically different, with the exception of ventricular bigeminy which was more often observed in grp B. A decline in the diastolic blood pressure was observed in pts with very severe obstruction (> 3.5 m/s, p < 0.05). Sensitivity of DSE was 84%, specificity 79%. No significant differences between pts with and without obstruction were observed. SUMMARY: Intraventricular obstructions during DSE are often observed in pts with normal systolic function at rest and during peak stress, especially in the case of left ventricular hypertrophy. (ABSTRACT TRU

Blood Flow Velocity↗
PubMed2005

Congenital right atrial diverticulum, atrial septal defect within the oval fossa, and complex pulmonary valvar obstruction in an infant with chromosome 8(p23.1) deletion.

We describe an unusual right atrial aneurysm, occurring with progressive obstruction of the right ventricular outflow tract and increasing cyanosis, in a nine-month-old boy with chromosome 8(p23.1) deletion. Surgical resection of the diverticulum, and relief of the right ventricular obstruction, was successful, although impairment of right ventricular compliance persists after 19 months follow-up.

Chromosome Deletion↗
PubMed2006

Management of right ventricular outflow tract reactivity following pulmonary valve dilatation under general anesthesia: experience of a medical mission.

During a recent volunteer medical mission to the Dominican Republic, we administered anesthesia to a child with severe pulmonary valvular stenosis and suprasystemic right ventricular pressure. This patient underwent a balloon pulmonary valvuloplasty but then developed worsening right ventricular outflow tract obstruction that required immediate therapy to prevent a low cardiac output state. As the development of hyperdynamic right ventricular outflow tract obstruction cannot be predicted, we emphasize the need for preemptive hydration and beta-blockade therapy prior to balloon dilatation.

Adolescent↗
PubMed1976

Clinical experience with the use of a valve-bearing conduit to construct a second left ventricular outflow tract in cases of unresectable intra-ventricular obstruction.

Two patients, ages 7 and 17, with unresectable obstructions within the left ventricular cavity, have been managed by interposing a conduit bearing a porcine aortic valve between the apex of the left ventricle and the infra-renal abdominal aorta. The younger child had idiopathic hypertrophic subaortic stenosis (IHSS) recognized in infancy. At the age of three, a right ventricular myomectomy and a trans-aortic left ventricular myotomy were performed. Symptoms were progressive with congestive failure, diaphoresis, syncope , and angina pectoris. Following construction of a second left ventricular outflow tract with relief of intraventricular obstruction, the patient has become asymptomatic. The second patient has fibrous tunnel obstruction of the left ventricular outflow tracting providing a 100 mm Hg gradient. Fibrous tissue was resected in part through the transaortic route, and a second outflow tract was constructed. A postoperative cardiac catheterization revealed an obliteration of the previous intraventricular gradients and an equal distribution of left ventricular output through the two available outflow tracts. She remains asymptomatic.

Adolescent↗
PubMed2005

Radiofrequency catheter septal ablation for hypertrophic obstructive cardiomyopathy in childhood.

Two patients, a 5 year old boy with progressive hypertrophic obstructive cardiomyopathy and increasing symptoms despite appropriate pharmacologic therapy and an 11 year old girl with symptoms of tiredness and peak instantaneous LVOT gradient of 80 and 90 mmHg respectively were considered for radiofrequency catheter septal ablation, to relieve the left ventricular outflow tract obstruction. Via a femoral arterial approach, the His bundle was initially plotted and marked using the LocaLisa navigation system. Subsequently, using a cooled tip catheter a series of lesions was placed in the hypertrophied septum, commencing distally in the ventricle and proceeding towards the aortic valve, taking care to stay away from the His bundle. The procedure was deemed to be completed when the entire extent of the hypertrophied septum had been treated. In the boy the procedure was complicated by two episodes of ventricular fibrillation, requiring DC cardioversion, but without any neurologic sequelae. The peak to peak gradient between left ventricle and aorta was 50 mmHg and 60 mmHg respectively pre-ablation, and remained unchanged immediately after. Both patients were discharged from the hospital 48 hours later. Serial measurement of serum Troponin T and CK-MB isoenzyme confirmed significant myocardial necrosis. Follow-up echocardiography at 7 days and at 6 weeks post-ablation respectively confirmed a beneficial hemodynamic result, with reduction of left ventricular outflow obstruction and relief of symptoms. In young children, in whom alcohol induced septal ablation is not an option, radiofrequency catheter ablation offers an alternative to surgery, with the benefits of repeatability and a lower risk of procedure-related permanent AV block.

Cardiomyopathy, Hypertrophic↗
PubMedDate not supplied

Effect of beta-blockade on symptomatic dexamethasone-induced hypertrophic obstructive cardiomyopathy in premature infants: three case reports and literature review.

OBJECTIVE: The objective of this study was to assess the efficacy of beta-blockade on clinically significant left ventricular outflow tract obstruction in premature infants treated with dexamethasone because of bronchopulmonary dysplasia. STUDY DESIGN: Case reports are presented of three premature infants (mean gestational age 27 weeks) cared for in the intensive care nursery in whom clinically significant septal hypertrophy and left ventricular outflow tract obstruction developed during dexamethasone treatment for bronchopulmonary dysplasia. The infants were treated with oral propranolol. Serial physiologic and echocardiographic parameters were followed. Physiologic data were analyzed with an analysis of variance, with the Kruskal-Wallis test used for nonparametric data. A p value < 0.05 was considered statistically significant. RESULTS: Oral administration of the beta-blocker propranolol resulted in clinical and echocardiographic improvement of the left ventricular outflow tract obstruction. One patient had a lower average heart rate and two patients had lower average mean blood pressure values during propranolol treatment, none of which was clinically significant. None of the patients had worsening of the respiratory status. CONCLUSION: beta-blockade treatment was well tolerated and may be beneficial in relieving symptomatic steroid-induced left ventricular outflow tract obstruction in premature infants.

Adrenergic beta-Antagonists↗
PubMed1985

Clinical use of ultrashort-lived radionuclide krypton-81m for noninvasive analysis of right ventricular performance in normal subjects and patients with right ventricular dysfunction.

The ultrashort-lived radionuclide krypton-81m, eluted in 5% dextrose from a bedside rubidium-81m generator, was intravenously infused for rapid imaging of the right-sided heart chambers in the right anterior oblique projection adjusted for optimal right atrioventricular separation. Left-sided heart and lung background was minimized by rapid decay and efficient exhalation of krypton-81m, requiring no algorithm for background correction. A double region of interest method decreased the variability in the assessment of ejection fraction to 5%. In 10 normal subjects, 11 patients with pulmonary hypertension, 4 patients with right ventricular outflow tract obstruction and 4 patients with right ventricular infarction, right ventricular ejection fraction determined by krypton-81m equilibrium blood pool imaging ranged from 14 to 76%. The correlation between these values and those determined by cineangiography according to Simpson's rule was close: r = 0.93 for all data points (p less than 0.001), r = 0.92 for studies at rest (p less than 0.001) and r = 0.93 for exercise studies (p less than 0.001). Exercise-related changes in right ventricular function revealed a disturbed functional reserve with pulmonary hypertension and right ventricular infarction, whereas in compensated right ventricular outflow tract obstruction there was a physiologic increase in ejection fraction with exercise (p less than 0.001). Thus, equilibrium-gated right ventricular imaging using ultrashort-lived krypton-81m is a simple, accurate and reproducible method with potential for serial assessment of right ventricular ejection fraction in a variety of right ventricular anatomic and functional abnormalities, both at rest and during exercise. Advantages of this method include an extremely low radiation dose to patients and clear right atrioventricular separation without the need to correct for background activity.

Adult↗
PubMed2005

Septal myectomy for obstructive hypertrophic cardiomyopathy.

Septal myectomy effectively relieves left ventricular outflow tract obstruction (LVOTO) and cardiac symptoms in both adults and children with obstructive hypertrophic cardiomyopathy (HCM). Abnormal attachments of the papillary muscles and chordae and other cardiac lesions can be repaired at the same time. Early mortality for isolated septal myectomy in both children and adults is low (0% to 2.5%). Median echocardiographic LVOT gradients at rest on late follow-up have been as low as 0 to 5 mm Hg. Symptomatic improvements after myectomy occurs in the majority; 90% of patients improve by at least one functional class, and most remain improved on late follow-up. Late survivorship compares very favorably with the natural history of nonoperated patients with symptomatic obstructive HCM. These results serve as a basis for comparison with newer nonsurgical alternatives.

Adolescent↗
PubMed1992

Ventricular septal defect with tricuspid pouch with and without transposition. Anatomic and surgical considerations.

In a 10-year review, patients operated on for ventricular septal defect and tricuspid valve pouch were divided into two groups, because the effect of the tricuspid valve pouch is influenced by which ventricle has the higher pressure. Group I comprised patients with ventricular septal defect without transposition of the great arteries and group II, ventricular septal defect with transposition. In 72 of 392 group I patients, the septal tricuspid valve leaflet was incised to expose the edges of the hidden ventricular septal defect to accomplish proper anatomic repair. Forty-eight patients had a tricuspid valve pouch, the diagnosis being established by angiography, echocardiography, or at operation. Ages at operation ranged from 5 months to 22 years and the pulmonary-systemic flow ratio ranged from 1 to 3.4, with 16 being less than 1.5. In one patient the pouch produced a 40 mm Hg pressure gradient in the right ventricular outflow tract. At operation, through a transatrial approach, the tricuspid valve pouch was opened radially, the actual ventricular septal defect patched, and the tricuspid valve leaflet repaired. There were no deaths, no significant intraoperative or postoperative morbidity, and no tricuspid valve dysfunction. The average postoperative hospital stay was 4.8 days. In group II, six of 83 patients operated on for transposition with ventricular septal defect had significant left ventricular outflow tract obstruction from the tricuspid valve pouch. Five of six had a Mustard procedure, two requiring a left ventricular-pulmonary artery conduit, and in two of the six the ventricular septal defect was closed through the pulmonary artery. One patient had heart transplantation after a Mustard repair and tricuspid valve replacement. The sixth patient in group II had a successful arterial switch at 9 years of age, after the presence of left ventricular outflow tract obstruction was proved to be due to the pouch. The presence of a tricuspid valve pouch in group I may lead the surgeon to close false small openings produced by the pouch rather than the actual ventricular septal defect. Incising the pouch is safe and essential for proper exposure and secure closure of the true defect. In group II, the systemic right ventricular pressure can push the pouch into the left ventricular outflow tract, causing significant obstruction, and may contribute to tricuspid valve insufficiency after atrial baffle repair. Arterial switch is preferred because it returns the obstructive tricuspid valve pouch and abnormal tricuspid leaflet to the lower pressure pulmonic right ventricle.

Child↗