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PubMed1995

[Evaluation of cardiorespiratory function in children and adolescents with repaired tetralogy of Fallot].

METHODS: To evaluate the cardiopulmonary exercise response of children and youngs operated upon for Tetralogy of Fallot (ToF) and to establish possible relationship with clinical and echocardiographic parameters we studied 24 pts, 14 males and 10 females, aged 14.5 +/- years; the age at repair was 5.2 +/- years and follow-up after correction was 8.6 +/- 3.2 years. All the pts were in NYHA functional class I; 8 pts had residual hemodynamic sequelae and 3 pts were on oral treatment. Cardiopulmonary exercise response with bicycle ergometer and incremental workload (25 watts/2 minutes), respiratory gas measurement with peak oxygen consumption (peak VO2) and ventilatory anaerobic threshold (VAT), were investigated in each patient. The data obtained were compared with those of control group of 103 healthy children and adolescents (59 males, 44 females, age 12.9 +/- 2.4 years) to the purpose of statistical analysis. RESULTS: The series of operated ToF pts showed 15-20% reduction in cardio-respiratory parameters, compared to healthy controls. a) Pts operated after the age of 5 years showed a significant reduction in peak VO2 compared to those operated at an earlier age (21 +/- 3.4 vs 35.4 +/- 7.5, p = 0.001) with; b) inverse correlation between peak VO2 and age at operation (r = -0.5, p = 0.01); c) 8 pts with residual hemodynamic sequelae (pulmonary regurgitation and/or ventricular outflow obstruction) showed the worse cardio-pulmonary capacity (peak VO2 27.5 +/- 7 vs 36.1 +/-8.1, p<0.02; VAT 20.4 +/- 5.2 vs 29.5 +/- 4.4, p<0.02; d) a chronotropic limitation was also observed in the group of pts when compared to healthy controls (peak HR 177 +/- 17 vs 188 +/- 11, p<0.001). CONCLUSION: Our study on pts operated upon for ToF showed a significant relation between age at surgery, hemodynamic sequelae and cardiopulmonary exercise response. Since this study has considered pts repaired in the two past decades, we believe that the present approach to ToF with early correction through atriotomy if possible and small outflow patch, may further improve the exercise capacity at a long-term follow-up.

Adolescent↗
PubMed1977

Long-term results of the Mustard procedure.

Over a 10-year period, 123 patients with transposition of the great vessels underwent the Mustard procedure. The hospital mortality for the series was 10.6%. There were seven late deaths, five of which were presumable due to arrhythmia. Sinus rhythm was noted postoperatively in 53% of the patients. Almost all the survivors had achieved catch-up growth when evaluated 6 months to 10 years later. A growth spurt was more consistently seen in the patients who were operated on under 2 years of age. Physical endurance and school performance were on a par with their normal peers or better in about half of the survivors. Severe neurologic problems were present in five patients. Postoperative catheterizations in 42 patients showed a rather high incidence of residual interatrial shunts, mild left ventricular outflow obstruction, and mild superior vena caval obstruction. Pulmonary venous obstruction and serious tricuspid regurgitation were not encountered.

Adolescent↗
PubMed1976

Effects of acutely increasing systemic vascular resistance on oxygen tension in tetralogy of Fallot.

Effects of phenylephrine hydrochloride on the degree of hypoxia were studied in six cyanotic patients with tetralogy of Fallot. Baseline aortic and right atrial oxygen saturations, blood gas tensions, pH, and indicator-dilution curves were obtained under stable conditions. Phenylephrine was infused while systemic arterial pressure was monitored continuously. Aortic and right atrial blood samples were measured at each 10 mm Hg systolic pressure increment and decrement and analyzed for pH, PO2, PCO2, and oxygen saturation. A 40 mm Hg peak systolic aortic pressure rise was the arbitrary end point for phenylephrine infusion and the indicator-dilution curve repeated. Aortic oxygen tensions rose in all from 4 to 28 mm Hg (mean, 14 mm Hg). The net right-to-left shunt decreased from 10% to 40% (mean, 25%) with phenylephrine infusion as compared to the shunt under basal conditions. The presumed mechanism related to the increase in systemic vascular resistance relative to right ventricular outflow obstruction with resultant augmentation of pulmonary blood flow. It is concluded that acutely raising systemic vascular resistance in patients with tetralogy of Fallot using phenylephrine infusion has a beneficial effect on systemic arterial oxygen level and might be the medical treatment of choice for protracted hypoxic spells.

Child↗
PubMedDate not supplied

[Transthoracic and transesophageal echocardiography in the study of adults with congenital cardiopathy and infectious endocarditis].

Twenty-four adults (average age 28 years) patients with congenital heart disease were examined; infective endocarditis was diagnosed in all of them by Duke criteria and was confirmed in 18 by surgery and/or pathology. Patients were divided into 2 groups. Group A was made up of 13 patients with left ventricular outflow obstruction, including ten with bicuspid aorta. Group B was made up of 11 patients with shunts (PDA or VSD), either isolated or associated with other abnormalities. The principal alterations associated with the infectious processes were trauma to the endocardium or vascular endothelium from accelerated turbulent flow (jet lesion) and valvular deformities. The principally transesophageal echocardiographic recordings showed infective vegetations on the four cardiac valves, mural endocarditis in both ventricles and right atrium, perivalvular abscesses and fistulae. The echocardiographic information aided in selecting the type of treatment in this group of patients with high intrahospital mortality (25%).

Abscess↗
PubMed1994

Right-ventricular myxoma presenting as right-ventricular outflow-tract obstruction--case report and review of the literature.

Myxoma of the right ventricle is of very rare occurrence. An adult male patient presented with Class III dyspnoea and occasional haemoptysis and clinically was suspected to have pulmonary stenosis. Magnetic resonance imaging study revealed presence of myxoma arising from the right-ventricular free wall and prolapsing into the pulmonary artery but not involving the pulmonary valve. The myxoma was excised via right ventriculotomy using cardiopulmonary bypass. The patient had an uneventful recovery. The relevant literature is reviewed.

Adult↗
PubMedDate not supplied

[Reconstructive surgery of idiopathic hypertrophic subaortic stenosis with dynamic obstruction of the left ventricular outflow tract causing severe mitral insufficiency].

Hypertrophic obstructive cardiomyopathy (HOCM) is an idiopathic disease frequently associated with systolic anterior motion (SAM). The anterior leaflet of mitral valve is sucked by Ventury effect into the left ventricle outflow tract making subaortic stenosis more severe and producing mitral insufficiency at the same time. Septal myectomy along with mitral valve replacement has been the treatment of choice for a long time. An understanding of pathoanatomy and hemodynamics of the disease has opened possibility for total reconstructive treatment of both subaortic stenosis and mitral insufficiency in such patients. This is a case report of 50-year-old male with severe subaortic stenosis (136/70 mmHg) due to HOCM and SAM along with grade IV mitral insufficiency. Septal myectomy was performed. Mitral insufficiency was managed by reducing the height of posterior cusp along with remodeling of mitral annulus by Carpentier-Classic ring. In that way, subaortic obstruction was reduced to 30.9/10 mmHg while mitral insufficiency was lowered to negligible level. The patient was discharged from hospital with sinus rhythm eight days after the surgery.

Cardiomyopathy, Hypertrophic↗
PubMed1993

Obstruction of the left ventricular outflow tract: anatomical observations and surgical implications.

Obstruction within the outflow tract from the left ventricle can take several anatomic forms. To understand better these substrates, we reviewed the anatomy in the normal heart and, with this background, focused on the malformations observed at each level of the outflow tract which produce stenosis. We examined 75 malformed hearts and reviewed the literature pertinent to surgical aspects of obstruction. Close study of the normal aortic valve shows the lack of any discrete fibrous structure which can be described in terms of a ring-like annulus. The semilunar attachment of the leaflets makes a crown-shaped arrangement at the ventriculo-arterial junction rather than a strict ring. In the pathological study, valvar abnormalities were found in 45 cases. The valve had three leaflets in 20 cases, two leaflets in 24 cases and one leaflet in to the other. In two cases, additional obstruction was found at the sinutubular junction. Subvalvar stenosis was found in 30 hearts, the aortic valve being trifoliate in 28 and bifoliate in 2. The main substrate of subvalvar obstruction was posterior malalignament of the outlet septum (40%), followed by muscular septal hypertrophy (23%); obstruction was also an intrinsic feature in association with atrioventricular septal defects (14%). Although rare in our material, it can also be due to a fibrous or fibromuscular shelf. In our review of the literature, we have highlighted the various forms of valvar malformation and commented on the surgical options. Clear analysis of both the level of obstruction, and its precise anatomic substrate are essential for optimal surgical intervention.

Adolescent↗
PubMed1997

Long-term effects of dual chamber pacing in patients with hypertrophic cardiomyopathy without outflow tract obstruction at rest.

BACKGROUND: Atrioventricular-synchronous pacing is beneficial in patients with hypertrophic obstructive cardiomyopathy. The effects of pacing in patients without significant left ventricular outflow tract obstruction at rest are, however, less well explored. This study compares the long-term outcome of pacing patients with and without significant left ventricular outflow tract obstruction at rest. METHODS: Forty-one patients with hypertrophic obstructive cardiomyopathy were studied, 19 with a left ventricular outflow tract gradient < 40 mmHg at rest, but exceeding 50 mmHg during provocation with isoproterenol (group A), and 22 with a left ventricular outflow tract obstruction > 40 mmHg at rest (group B). Before the implantation of a permanent pacemaker, the patients were studied according to a temporary pacing protocol. This included graded isoproterenol provocation of the left ventricular outflow tract obstruction, which was assessed by echo Doppler. Following permanent pacemaker implantation, the patients were regularly followed up with echo Doppler, exercise testing and monitoring of the clinical condition. RESULTS: Isoproterenol provocation was reproducible and the technique did not cause any clinically important side effects. Left ventricular outflow tract gradient reduction after chronic pacing did not differ between the two groups. In group A, it decreased from 98 +/- 30 mmHg in sinus rhythm to 42 +/- 26 mmHg during pacing. The corresponding values in group B were 87 +/- 40 mmHg to 36 +/- 24 mmHg. The clinical condition improved similarly in the two groups. Exercise capacity increased significantly and perceived dyspnoea and angina pectoris were significantly lower at submaximal levels of exercise after 6 months of pacing. CONCLUSION: Hypertrophic obstructive cardiomyopathy patients who only exhibit significant left ventricular outflow tract obstruction during provocation benefit as much from pacemaker treatment as do patients who already have significant obstruction at rest. Isoproterenol is a safe and reproducible method for pre-pacing evaluation of hypertrophic obstructive cardiomyopathy patients.

Adult↗
PubMed1997

Nonsurgical septal reduction for hypertrophic obstructive cardiomyopathy: outcome in the first series of patients.

BACKGROUND: Some patients with hypertrophic obstructive cardiomyopathy may gain symptomatic relief from a reduction in the extent of obstruction to left ventricular outflow. We present the outcome of the first series of patients treated with an alternative method of gradient reduction using catheter techniques. METHODS AND RESULTS: Eighteen patients were treated with selective intracoronary alcohol injection to induce localized septal infarction. Patients underwent echocardiographic measurement of left ventricular dimensions and Doppler echocardiographic evaluation of left ventricular outflow tract gradients before the procedure, on the first postoperative day, and at a median follow-up of 3 months after the procedure. In addition, patients underwent exercise testing and symptom evaluation before and 3 months after nonsurgical septal reduction. There was a significant reduction in left ventricular outflow tract obstruction after the procedure (preprocedure, 67 mm Hg [95% CI, 48 to 87 mm Hg]; postprocedure, 25 mm Hg [95% CI, 16 to 34 mm Hg]; P=.0006), which persisted at 3-month follow-up (22 mm Hg [95% CI, 12 to 32 mm Hg]; P=.001). This was associated with a significant improvement in symptoms. There was a small but not significant increase in exercise capacity (n=10; preprocedure, 418 seconds [95% CI, 273 to 563 seconds]; postprocedure, 452 seconds [95% CI, 283 to 621 seconds). Left ventricular dimensions were not significantly altered by nonsurgical septal reduction. CONCLUSIONS: Nonsurgical septal reduction significantly reduces left ventricular outflow tract obstruction and improves symptoms in some patients with hypertrophic obstructive cardiomyopathy. The technique may provide an alternative to surgical myomectomy in selected patients.

Adolescent↗
PubMed2003

Hypertrophic obstructive cardiomyopathy: mechanism of obstruction and response to therapy.

Hypertrophic cardiomyopathy is a primary, usually familial, disorder of heart muscle whose primary feature is muscular hypertrophy without recognized cause that encroaches on the ventricular chamber, reducing chamber area and volume. In roughly 25% of cases, there is associated obstruction to left ventricular outflow (hypertrophic obstructive cardiomyopathy [HOCM]). This article details the mechanism of obstruction in HOCM, focusing on obstruction at the mitral valve level, and reviews the pharmacologic and surgical therapies currently available. Mainstays of pharmacologic therapy include b-blockers, calcium channel blockers (verapamil in particular), and/or disopyramide. Surgical therapies include septal myotomy/myectomy, which has become the gold standard to which other therapies are compared, and mitral valve replacement. During the past 10 years, atrio-ventricular sequential pacing and alcohol septal ablation have been proposed as less invasive alternatives to surgery. A single, optimal therapy for patients with HOCM and refractory symptoms has not been established, and decisions regarding surgical versus noninvasive therapies need to be individualized based on functional status, comorbidities, local expertise in the surgical and nonsurgical techniques, and patient preference.

Adrenergic beta-Antagonists↗
PubMed1981

Results of the Mustard operation for dextro-transposition of the great arteries.

One hundred twenty patients with dextro-transposition of the great arteries (TGA) underwent intra-arterial baffle repair using thin Dacron fabric from 1971 to 1979. The ages of the patients ranging from 29 days to 17 years (mean age 28 months). Thirty-five patients had undergone 49 preliminary palliative operations. Early postoperative mortality was 4.8% for patients with simple TGA but was higher among patients with associated ventricular septal defect (26%), VSD and left ventricular outflow tract obstruction (28.5%) and intact ventricular septum with left ventricular outflow tract obstruction (12.5%). Early nonfatal postoperative complications included low cardiac output (23.3%), respiratory insufficiency (35.8%), junctional rhythm (34.1%), superior vena caval (SVC) obstruction (9.1%), and chylothorax (7.5%). Late postoperative mortality for all groups was 7.5% (nine patients). Late cardiac dysrhythmias occurred in 33 patients (40.7%). Normal sinus rhythm has been preserved in all patients since direct, high SVC cannulation was instituted. Late postoperative hemodynamic and angiographic evaluation in 61 patients revealed severe to total SVC obstruction in 12 patients (20.2%) and pulmonary venous obstruction in four patients (6.5%). Among the latter, two patients died following reoperation and another patient died without operation. SVC obstruction was clinically important in only three patients, two of whom have undergone successful reoperation. All other late survivors are acyanotic and clinically well. The Mustard operation has dramatically improved the survival rate and quality of life for patients with TGA. However, postoperative caval and pulmonary venous obstruction are problems which require additional technical modifications and stimulate the search for alternative corrective operations.

Adolescent↗
PubMed1977

Primary sarcoma of the pulmonary trunk and/or right or left main pulmonary artery--a rare cause of obstruction to right ventricular outflow. Report on two patients and analysis of 35 previously described patients.

Clinical and morphologic observations are described in two women with primary sarcoma of the pulmonary trunk, and observations in 35 previously described patients with primary sarcoma involving a major extrapulmonary pulmonary artery are summarized. The neoplasm produces symptoms by causing obstruction to right ventricular outflow or by dislodging tumor fragments to the smaller intrapulmonary pulmonary arteries with or without pulmonary infarction. The sarcoma nearly always arises from the pulmonary trunk to which it is firmly attached. Although it grows to a large size within the lumen, it infrequently, despite its highly malignant histologic pattern, extends through the wall of the pulmonary trunk or metastasizes outside the pulmonary circulation. It may mimic a variety of more common disorders. Diagnosis can be achieved by angiography and treatment starts with total excision.

Adult↗
PubMed2005

Repaired tetralogy of Fallot in the adult.

The majority of persons living with tetralogy of Fallot are now adults and may face a number of long-term cardiac problems that necessitate reoperation. These problems include pulmonary regurgitation, tricuspid regurgitation, ventricular tachycardia, atrial flutter and/or fibrillation, pulmonary artery branch stenoses, right ventricular aneurysms, right ventricular outflow tract obstruction, residual ventricular septal defects, and coronary artery disease. Management approaches to these potential problems are discussed. Issues related to genetics, pregnancy, infective endocarditis, insurability, and employment are also reviewed with specific reference to the individual with repaired tetralogy of Fallot.

Adult↗
PubMed1990

Unilateral pulmonary hypertension as a result of chronic high flow to one lung.

The patient presented is a 27-month-old male with complex congenital heart disease consisting of severe left ventricular outflow tract obstruction and ventricular septal defect who had undergone a pulmonary trunk-to-aorta graft and a pulmonary artery banding procedure as a neonate. Sometime after this repair, but at least 15 months prior to presentation to this institution for placement of an aortic homograft, the pulmonary trunk band apparently slipped and migrated over the right pulmonary artery, severely limiting blood flow to the right lung and increasing flow to the left. Severe pulmonary hypertension developed, with a main pulmonary artery pressure of 94/53 mm Hg. We present clinical and radiographic evidence that the resulting chronic high blood flow and pressure in the left lung ultimately resulted in hypoperfusion of that lung, presumably secondary to chronic vascular changes with greatly increased vascular resistance. Upon surgical repair and removal of the constrictive band from the previously banded right PA, blood flow was increased to the low resistance right lung causing right-sided unilateral pulmonary edema, ventilation/perfusion mismatching, and severe hypoxemia. Perfusion studies documented that less than 10% of blood was directed to the left lung, with greater than 90% to the right. Perfusion studies 9 months postoperatively continued to demonstrate minimal blood flow to the left lung. Discussion focuses on the effects of mechanical forces and the interaction with hypoxia in causing pulmonary vascular remodeling.

Child, Preschool↗
PubMed2000

The effect of the atrioventricular interval during atrioventricular sequential pacing on the hemodynamics in dynamic obstruction of the left ventricular outflow tract in dogs.

The present study was performed to clarify the mechanism involved in the reduction of the pressure gradient in the left ventricular outflow tract of patients with hypertrophic obstructive cardiomyopathy when treated with atrioventricular (AV) sequential pacing. The effect of AV sequential pacing with variable AV intervals on the hemodynamics and dyssynchronous wall motion was experimentally studied using echocardiography in the dynamic obstruction of the left ventricular outflow tract created by dobutamine infusion in 17 dogs. The pressure gradient of the left ventricular outflow tract decreased with shortening of the AV interval during AV sequential pacing. Also, the dyssynchrony time, defined as the difference in the time between the intraventricular septum and posterior wall during the systolic phase recorded with M-mode echocardiography, increased with shortening of the AV interval during AV sequential pacing. However, very short AV intervals produced a significant decrease in the aortic pressure and increase in the pulmonary capillary wedge pressure. The dyssynchrony time showed a positive liner correlation with the percentage reduction in the pressure gradient of the left ventricular outflow tract (R=0.794, p<0.0001). It was concluded that dyssynchronous wall motion in the left ventricle was produced by pacing from the right ventricular apex and resulted in a reduction in the pressure gradient of the left ventricular outflow tract. Optimization of the AV interval during AV sequential pacing may play an important role in improving the hemodynamics in dynamic obstruction of the left ventricular outflow tract.

Animals↗
PubMed1986

Right ventricular inflow and outflow obstruction due to adrenal cell carcinoma.

A 48-year-old man with surgically removed adrenal cell carcinoma presented with shortness of breath and fatigue. Physical examination revealed neck vein distention and a new systolic murmur. Echocardiography showed a right ventricular mass causing inflow and outflow tract obstruction. These findings were confirmed at surgery.

Adrenal Gland Neoplasms↗
PubMed1996

The effect of the ingestion of ethanol on obstruction of the left ventricular outflow tract in hypertrophic cardiomyopathy.

BACKGROUND: Ethanol causes vasodilation, which might have an adverse effect, due to increased obstruction of the left ventricular outflow tract, in patients with hypertrophic obstructive cardiomyopathy. We assessed the hemodynamic effects of the ingestion of ethanol, in an amount commonly consumed socially, in patients with hypertrophic cardiomyopathy. METHODS: We performed echocardiography in 36 patients before and several times after the ingestion of either 50 ml of 40 percent ethanol or an isocaloric placebo with the aroma of rum. Each patient received both ethanol and placebo, on different days. The patients, but not the physicians, were blinded to the content of the drink. We measured the sizes of the left atrium and left ventricle, the left-ventricular-wall thickness, blood pressure, heart rate, the degree of systolic anterior motion of the mitral valve, and the pressure gradient across the left ventricular outflow tract. RESULTS: The ingestion of ethanol regulated in a significant drop in the mean (+/- SD) systolic blood pressure (from 130.5 +/- 18.6 to 122.5 +/- 20.3 mm Hg, P<0.001), a significant increase in systolic anterior motion of the mitral valve (from a grade of 2.1 to a grade of 2.5, P<0.001), and a 63 percent increase in the mean gradient across the left ventricular outflow tract (from 38.1 +/- 26.5 to 62.2 +/- 42.4 mm Hg, P<0.001). These changes, which were not associated with symptoms, did not occur after the ingestion of placebo. CONCLUSION: The ingestion of a small amount of ethanol caused an increase in the gradient across the left ventricular outflow tract in patients with hypertrophic obstructive cardiomyopathy, which could have and adverse clinical effect.

Adult↗