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At least 631 records · Page 35Linked to original sources
PubMed1999

Obstruction of the right ventricular outflow tract caused by a tuberculoma in a patient with ventricular septal defect and aneurysm of the membranous septum.

Reported here is an obstruction of the right ventricular outflow tract caused by a tuberculoma in a 15-year-old boy who presented with a ventricular septal defect. The obstruction was discovered at surgery and the tuberculous aetiology was only demonstrated histologically. To the authors' knowledge, this is the first report of a tuberculoma of the heart associated with congenital heart disease.

Adolescent↗
PubMed2006

Changes in pulmonary venous Doppler parameters in fetal cardiac defects.

OBJECTIVES: Recent observations in pediatric cardiological studies have prompted discussion on the possible role of intrauterine pulmonary venous changes in neonatal and postoperative outcome of infants with congenital heart defects. This study analyzes changes of Doppler blood flow velocity waveforms in the pulmonary veins of fetuses with different cardiac defects. METHODS: Eighty fetuses (mean gestational age, 27 weeks) with prenatally diagnosed cardiac defects were classified into one of five groups: obstructed left atrium, other left ventricular outflow tract obstruction, right ventricular outflow tract obstruction, miscellaneous cardiac defects and total anomalous pulmonary venous drainage. Doppler examination of the pulmonary veins was performed and the time velocity integral (TVI), end-diastolic (A) velocity, and pulsatility index for veins (PIV) were compared with reference ranges. RESULTS: Fetuses with infradiaphragmatic total anomalous pulmonary venous drainage showed a continuous Doppler flow pattern instead of the typical pulsatile waveform pattern. In fetuses with obstructed left atrium and restrictive foramen ovale, a reversed A-velocity and increased PIV were found. In five of the eight fetuses with left outflow tract obstruction but patent mitral valve, PIV was increased. In the other groups there were no obvious changes in Doppler parameters. CONCLUSIONS: We suggest routine examination of the pulmonary veins with pulsed Doppler ultrasound in every fetus with a prenatally diagnosed heart defect. Such Doppler parameters could be used in future as cut-offs for the recently reported in-utero atrial septostomy to decompress an obstructed left atrium.

Blood Flow Velocity↗
PubMed1993

Fatal obstruction of the left ventricular outflow tract caused by low-profile bioprostheses in the mitral valve position.

Two cases of fatal left ventricular outflow tract obstruction following mitral valve replacement with low-profile bioprostheses are described. This unfortunate experience shows that correct orientation of the prosthesis is mandatory also when using low-profile bioprosthetic valves to avoid this complication, particularly in patients with a small left ventricular cavity.

Aged↗
PubMed1984

Discrete subaortic stenosis.

From 1971-1981, 18 patients with discrete subaortic stenosis were treated surgically at the Medical University of South Carolina. Echocardiography was diagnostic in 10 of 11 patients in whom it was used. Preoperative cardiac catheterization was performed in all patients. The preoperative left ventricular outflow systolic pressure gradient was 82.0 +/- 27.2 mmHg (mean +/- SD) (range 30-145). In 16 (88.8%) patients excision of the subaortic membrane was complete, and relief of left ventricular outflow obstruction was good. The excision was incomplete in 2 patients; one required reoperation for residual gradient and developed complete heart block, and the other had a residual gradient of 60 mmHg and was in New York Heart Association functional class II when lost to follow-up. These data suggest that complete excision of the discrete subaortic stenosis is important to achieve good relief of left ventricular outflow obstruction.

Adolescent↗
PubMed1986

Postoperative long-term results in total correction of tetralogy of Fallot: with special reference to method and degree of relief of right ventricular outflow tract obstruction.

Late results were studied in 63 patients who underwent complete repair of tetralogy of Fallot. Mild pulmonary stenosis (PS) was present in 73%, moderate PS in 17% and severe PS in 10% of the patients. When a transannular patch was used, wider enlargement of the pulmonary annulus did not always relate to a decrease in right ventricular pressure and right ventricular to pulmonary artery pressure gradient in the late postoperative period. Pulmonary regurgitation (PR) of grade 2 or less did not relate to the late postoperative hemodynamics and cardiac function. PR of grade 3 or over led to right ventricular and pulmonary artery hypertension, and to increases in right ventricular end-diastolic volume and CTR. PR of grade 4 impaired left ventricular function. PR of grade 3 or over with moderate PS led to elevation in right ventricular end-diastolic pressure. In patients with mild PS and PR of grade 2 or less, late postoperative hemodynamics and cardiac function were excellent. To maintain excellent postoperative hemodynamics and cardiac function, it is imperative to obtain PR of grade 2 or less and to use a procedure which will lead to excellent development of the pulmonary annulus. In conventional procedures using a transannular patch, a CSAI of less than 2.5 cm2/m2 and precise coaptation between the original pulmonary cusp and the cusp mounted on the patch will aid in avoiding significant PR.

Adolescent↗
PubMed1986

Development of severe left ventricular outflow tract obstruction over the course of 14 years: an unusual natural history of hypertrophic obstructive cardiomyopathy.

A patient with hypertrophic obstructive cardiomyopathy who when first seen had a normal physial examination, chest x-ray, and electrocardiogram, and no provokable gradient with isoproterenol at cardiac catheterization, was re-evaluated after 14 years. At the time of re-evaluation, she was found to have a typical systolic ejection murmur, cardiomegaly, left ventricular hypertrophy, a pseudoinfarction pattern on electrocardiography, and a significant subaortic gradient both by catheterization and by doppler. This case demonstrates that hypertrophic obstructive cardiomyopathy can be a progressive disease and that patients with this condition warrant careful follow-up. Echocardiography with doppler may provide an excellent noninvasive method of following these patients.

Cardiomegaly↗
PubMed2004

Primary cardiac tumor presenting as obstruction of the left ventricular outflow tract.

A transthoracic echocardiogram revealed 3 tumors in the left atrium of a 64-year-old woman, who died suddenly 8 months after resection of the tumors. Primary cardiac tumors are unusual and a case of postoperative left ventricular metastases of the atrial tumors resulting in left ventricular outflow tract obstruction is very rare occurrence.

Echocardiography, Doppler↗
PubMed1999

An equation to predict the changes in peak left ventricular pressure in hypertrophic obstructive cardiomyopathy after treatment: application to the administration of disopyramide.

A theoretical equation was derived based on the time-varying elastance model to predict theoretically the relationship between the delay in the onset of left ventricular outflow obstruction and the reduction in peak left ventricular pressure (LVP) caused by treatment in hypertrophic obstructive cardiomyopathy (HOCM). ECG, LVP, and other hemodynamic parameters were measured during catheterization at a constant heart rate with atrial pacing in 16 patients with HOCM before and after intravenous administration of disopyramide (1 mg/kg). After disopyramide administration, the duration between the R wave of the ECG and the onset of obstruction (T1) was prolonged significantly (from 117 +/- 30 to 155 +/- 32 ms, P < 0.0001), and peak LVP was reduced significantly (from 222 +/- 42 to 177 +/- 39 mmHg, P < 0.0001). The relation between the prolongation of T1 and the percent reduction in peak LVP was predicted well by the theoretical equation (coefficient of determination R2 = 0.926). Our model simplifies the therapeutic strategy for reducing the left ventricular outflow pressure gradient in patients with HOCM, which is to delay the time of onset of obstruction by some methods.

Adult↗
PubMed1986

Instantaneous pressure gradient: a simultaneous Doppler and dual catheter correlative study.

To more precisely measure the beat to beat and instantaneous pressure gradients across outflow stenotic lesions, simultaneous Doppler and dual catheter pressure gradient measurements were performed in 95 patients (mean age 42 years, range 1.5 to 85). There were 38 right ventricular and 62 left ventricular outflow obstructive lesions. Forty-nine patients also had a nonsimultaneous Doppler study performed within 7 days before catheterization. The simultaneous pressure waveforms and Doppler spectral velocity profiles were digitized at 10 ms intervals deriving maximal, mean and instantaneous gradients (mm Hg). For simultaneous maximal Doppler and catheter gradient measurements, the correlation coefficient (r) was 0.95 (SEE = 10 mm Hg), for Doppler and catheter mean gradients it was 0.94 (SEE = 8 mm Hg) and for maximal Doppler and peak to peak catheter gradients it was 0.92 (SEE = 13 mm Hg). The correlation of maximal and mean Doppler gradients with the respective catheter gradients was similarly high when the right and left ventricular outflow lesions were analyzed separately. However, the maximal Doppler gradient was significantly higher than the peak to peak catheter gradient. This was more evident with left ventricular outflow stenotic lesions. The correlation of the outpatient maximal Doppler and catheter gradients (r = 0.80, SEE = 17 mm Hg) was significantly lower than the simultaneous correlation (r = 0.96, SEE = 10 mm Hg) in the 49 patients with two Doppler studies. Continuous wave Doppler echocardiography accurately measures the instantaneous pressure gradient across both left and right ventricular outflow obstructive lesions. The maximal Doppler gradient should not be equated with the peak to peak catheter gradient.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2000

Postnatal growth in southern Chinese children with symptomatic congenital heart disease.

Many Western children with congenital heart disease (CHD) show significant growth retardation. In this study postnatal growth was examined in Chinese children with symptomatic CHD in Hong Kong, in relation to their diagnosis and the time of surgery. 363 children of four years old or younger, who were admitted at Grantham Hospital, Hong Kong, in 1994 and 1995, were subdivided into six diagnostic categories and categorised into cyanotic and acyanotic groups. While a reduced birth weight SDS was present in 18% of patients, at the time of operation approximately 40% of them had subnormal weight and height values. Girls were more impaired in weight and weight-for-height than boys (-1.90 SDS vs -1.52 SDS, and -0.90 SDS vs -0.46 SDS, respectively). Children with acyanotic lesions were more affected in growth than those with cyanotic lesions, but they were also operated on at an older age than children in the latter group. Left to right shunt and common intracardiac mixing were particularly associated with wasting; transposition of the great arteries and pulmonary outflow tract obstruction with stunting; while children with left ventricular outflow obstruction revealed a proportional growth retardation in weight and height. Age at operation did not seem to have an independent effect on postnatal growth in children with CHD. As with Western children, growth retardation is a common feature in Chinese children with symptomatic cardiac defects. Haemodynamics, age at operation and nutritional influences are discussed as potential aetiologic factors.

Birth Weight↗
PubMed1995

Fibrous obstruction within the left ventricular outflow tract associated with ventricular septal defect: a pathologic study.

OBJECTIVES: We examined the nature of ridges within the left ventricular outflow tract associated with ventricular septal defects that might be found by echocardiography. BACKGROUND: Echocardiography displays even small ridges well. Surgical removal of such ridges at the time of defect closure is recommended. METHODS: We examined 37 heart specimens with ventricular septal defects with a ridge, noting its nature and relation to the defect and adjacent valves. We excluded left ventricular outflow tract obstruction associated with complex lesions. RESULTS: Defects were perimembranous in 25 specimens, muscular in 8 and part of an atrioventricular septal defect in 5. Some hearts had multiple defects. Many of the original reports had not mentioned ridges. Three distinct ridge patterns were found. The first (n = 18) was a fold of endocardial tissue related to the membranous septum. The second (n = 12) was a defect of a fibrous nature; in 8 this was a discrete, protuberant fibrous ridge, and in 4 the obstruction was diffuse, which we termed keloidal. The third pattern (n = 7) lay circumferentially around the ventricular septal defect, seemingly associated with the defect's attempted spontaneous diminution in size. Endocardial folds were not found in specimens from patients > 5 years old. Fibrous and keloidal lesions, which may represent a continuum of progression, generally were found in specimens from older patients. Histologic studies of 17 specimens confirmed the morphologic findings. The endocardial folds were endothelial tissue, whereas the fibrous and keloidal ridges were of fibrous tissue, as were circumferential lesions. All specimens had mitral-semilunar valvular continuity. CONCLUSIONS: Endocardial fold and circumferential lesions appear to be benign. The endocardial folds arose from the membranous ventricular septum, were not protuberant and usually were found in younger patients. The fibrous ridges, in contrast, were protuberant and were always associated with the underlying muscle of the outlet septum. These pathologic distinctions may facilitate echocardiographic diagnosis and prognosis.

Adolescent↗
PubMed2003

Population dependent differences of distribution of congenital heart malformations.

The aim of the work was to study the pattern of congenital circulatory system malformations in the newborns in Upper Silesia, Poland (N = 355), and to compare it with the data known from the literature, predominantly with genetically very distant Chinese population from Hong Kong (N = 744). There were significantly more boys (about 60%) than girls (about 40%) in both groups. Much higher rate of the heart defects with pulmonary outflow obstruction was found in Hong Kong neonates (37.8%) than in the Polish ones (16.1%). Left ventricular outflow obstruction malformations were more common in Chinese group (22.7%) than in Polish one (14.1%), as well. On the other hand, Polish neonates were significantly more often admitted to cardiological hospital because of left-to-right shunts (37.7%) as compared to Chinese population (15.5%). The rate of complete transposition of great arteries was similar in both studied groups (12.1% in Poland versus 12.4% in Hong Kong). So called common mixing malformations were not significantly more often found in Polish newborns (12.1%) than in Hong Kong ones (8.3%). It is concluded that it significant race dependent distribution difference of congenital heart malformations exists between Polish (Silesian) and Chinese (Hong Kong) newborn populations. On the other hand the pattern of congenital heart malformations found in Polish newborns seems to be not very different from these ones, known from literature, described in the USA or in Europe.

Asian People↗
PubMed1998

[Cardiac metastasis of a plasmacytoma with clinical manifestations of an extensive pulmonary embolism. Obstruction of the right ventricular outflow tract].

HISTORY AND CLINICAL FINDINGS: A 48-year-old man with advanced light-chain plasmacytoma was admitted because of severe dyspnoea and tachycardia. Physical examination revealed peripheral cyanosis and signs of right heart failure. INVESTIGATIONS: The partial pressure of oxygen and CO2 in arterial blood were both reduces (72 mm Hg and 33 mm Hg, respectively). Liver enzyme activities were increased, there was right heart enlargement radiologically and the ECG showed low voltage and typical signs of right heart strain. Echocardiography revealed cardiac metastases of the plasmacytoma with subtotal right ventricular outflow tract obstruction (RVOTO), without any signs of pulmonary emboli. TREATMENT AND COURSE: Palliative radiotherapy to the heart reduced the intracardiac tumor size and improved the patients' general condition. The signs of the RVOTO were markedly reduced in both the ECG and the echocardiogram. But after this initial improvement pneumonia developed, of which the patient died. Autopsy revealed radiation pneumonia with extensive fibrosis as the immediate cause of death. CONCLUSION: In patients with advanced neoplasia cardiac metastasis should be included in the differential diagnosis of dyspnoea, tachycardia or hypotension of uncertain etiology. Echocardiography is the diagnostic tool of choice.

Blood Gas Analysis↗
PubMed1996

Effect of dual-chamber pacing on systolic and diastolic function in patients with hypertrophic cardiomyopathy. Acute Doppler echocardiographic and catheterization hemodynamic study.

OBJECTIVES: This study sought to evaluate prospectively the acute hemodynamic effect of dual-chamber pacing by using a combined hemodynamic approach of high fidelity pressure and Doppler velocity measurements. BACKGROUND: Dual-chamber pacing has been proposed recently as an alternative in the symptomatic treatment of patients with hypertrophic obstructive cardiomyopathy. Although early reports documented a decrease in left ventricular outflow tract gradient and symptomatic improvement, questions remain about the hemodynamic effects of dual-chamber pacing on systolic and diastolic function. METHODS: Twenty-nine patients with hypertrophic cardiomyopathy underwent a combined cardiac catheterization and Doppler echocardiographic study during normal sinus rhythm and P-synchronous pacing at various atrioventricular (AV) intervals. High fidelity pressure measurements of left ventricular inflow and left atrial pressures, ascending aortic pressure, thermodilution cardiac output and Doppler mitral flow velocity curves were obtained to evaluate both systolic and diastolic left ventricular function. RESULTS: During AV pacing at the shortest delay of 60 ms, there was a significant decrease in cardiac output (p < 0.05) and peak positive dP/dt (p < 0.05), an increase in mean left atrial pressure (p < 0.05) and a prolongation of tau, the time constant of relaxation (p < 0.05), compared with that during normal sinus rhythm. During pacing at the optimal AV delay (longest AV interval with pre-excitation), there was a similar trend, with deterioration in both systolic and diastolic function variables but of lesser magnitude than that during pacing at the shortest AV intervals. The deterioration in both systolic and diastolic function was present in 21 patients with and 8 without left ventricular outflow obstruction. There was a modest decrease in left ventricular outflow tract gradient from 73.3 +/- 45.0 (mean +/- SD) to 61.3 +/- 40.5 mm Hg (p = 0.03) during dual-chamber pacing at the optimal AV delay compared with that during normal sinus rhythm. CONCLUSIONS: The acute effect of pacing the right atrium and ventricle may be detrimental to both systolic and diastolic function of the left ventricle, particularly at the short AV intervals. Further studies of the long-term effects of dual-chamber pacing in carefully performed randomized studies are needed.

Blood Flow Velocity↗
PubMed2003

Dynamic obstruction of the left ventricular outflow tract in four young dogs.

Four young dogs presented for evaluation of left-sided systolic heart murmurs all showed echocardiographic changes consistent with dynamic left ventricular outflow tract (LVOT) obstruction and subjective evidence of concentric left ventricular hypertrophy. In three of the dogs, abnormal mitral valve apparatus and systolic anterior motion of the anterior mitral valve leaflet with associated mitral insufficiency were also detected. All dogs were medicated with a beta1-adrenergic antagonist. Subsequent examinations showed that the dynamic LVOT obstruction and left ventricular concentric hypertrophy had almost completely resolved. Dynamic LVOT obstruction is a rare condition of young dogs of different breeds. The precise aetiology of the condition remains uncertain. Whether resolution of the outflow obstruction in these four cases was a consequence of treatment or due to changes in ventricular architecture brought about by ageing cannot be established.

Administration, Oral↗