PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Ventricular Outflow Obstruction”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources
PubMed1997

Anatomic features and surgical strategies in double-outlet right ventricle.

BACKGROUND: The objective of this study was to review anatomic features and surgical strategies in children with double-outlet right ventricle (DORV) and to assess risk factors for early mortality. METHODS AND RESULTS: Records were reviewed of all children with DORV undergoing surgery between 1978 and 1993. Noncomplex patients (group 1) had atrioventricular (AV) concordance, a single ventricular septal defect (VSD), balanced ventricles, no straddling AV valves, and no major pulmonary artery anomaly. Group 2 (complex) comprised all remaining patients. Independent risk factors analyzed included location of the main VSD, presence of additional VSDs, coarctation, ventricular outflow obstruction, ventricular hypoplasia, age at operation, operation before 1985, previous palliation, and type of definitive operation. Of 193 patients, 117 were in group 1 and 76 in group 2. In 148 patients, biventricular repair was undertaken, including 111 of 117 group 1 patients and 37 of 76 group 2 patients. Early mortality was higher among group 2 patients undergoing biventricular repair than among group 1 patients (8 of 37 versus 4 of 111, P<.005) and higher than group 2 patients undergoing a Fontan procedure (none of 29, P<.01). Aortic arch obstruction, operation before 1985, and multiple VSDs were significant risk factors for mortality. Age <1 month (P<.05) and multiple VSDs (P<.005) were independent risk factors after definitive repair. Up-to-date follow-up is available on 144 surviving patients, with 127 (88%) in New York Heart Association class I and the remaining 17 in class II. Overall 10-year survival probability was 81%, whereas probability of survival, free from reoperation (after definitive surgery), was 65% at 10 years. CONCLUSIONS: Biventricular repair can be achieved in most patients with DORV with low risk. In complex DORV, a Fontan procedure is associated with a lower surgical mortality.

Adolescent↗
PubMed1991

The arterial switch repair and the obstructive right ventricular outflow tract: does it matter?

Right ventricular outflow tract obstruction (RVOTO) was resected in 5 of 78 neonates (6.4%) with complete transposition of the great arteries (TGA) and in 10 of 26 neonates and infants (38.5%) with double outlet right ventricle (DORV) or TGA associated with ventricular septal defect (VSD). The early mortality in the combined series was 7.7%. Morphologic indicators for RVOTO in TGA are abnormal spatial relations of the great arteries, abnormal coronary anatomy, small size of the aortic valve ring, hypoplasia or obstruction of the aortic arch and the presence of a malaligned VSD. Sizing of the RVOT and the aortic valve annulus should confirm the diagnosis and establish the indication for resection. Right ventricular outflow tract obstruction is important for the outcome of arterial switch operation (ASO) in neonates and infants with simple and complex TGA: if subaortic obstruction is anticipated and properly dealt with, the surgical risk of anatomic correction is not increased.

Double Outlet Right Ventricle↗
PubMed1999

Left ventricular outflow tract obstruction with mitral mechanical prosthesis.

Left ventricular outflow tract obstruction after mitral valve replacement may occur when the native mitral apparatus is preserved intact. Although it has usually been reported using bioprostheses, we present one case using a low-profile mechanical prosthesis. The reduction of left ventricular dimensions and valvular redundancy contributed to this complication. We obtained definitive relief of left ventricular outflow tract obstruction by transaortic exposure and partial resection of the obstructing tissue with the help of video-assisted cardioscopy.

Female↗
PubMed1996

Influence of right ventricular pacing site on left ventricular outflow tract obstruction in patients with hypertrophic obstructive cardiomyopathy.

OBJECTIVES: This study was designed to show the influence of right ventricular pacing site on left ventricular outflow tract obstruction during pacing treatment of patients with hypertrophic obstructive cardiomyopathy. BACKGROUND: Atrioventricular synchronous pacing has been reported to reduce left ventricular outflow obstruction and symptoms in patients with hypertrophic obstructive cardiomyopathy. A paradoxic septal movement induced by right ventricular pacing has been implicated as the mechanism behind the reduced left ventricular outflow tract obstruction; however, the importance of pacing site has not been clarified. METHODS: Cardiac output, measured invasively, and left ventricular outflow tract gradient, estimated by Doppler echocardiography, were studied in 15 patients with hypertrophic obstructive cardiomyopathy. Measurements were made with the right ventricular electrode in the septal and apical positions during temporary pacing and during sinus rhythm. RESULTS: Right ventricular apical pacing reduced the outflow tract gradient in all 15 patients to a mean +/- SD of 38 +/- 24 mm Hg from 96 +/- 33 mm Hg during sinus rhythm. During high septal pacing the outflow tract gradient was not reduced, remaining at 93 +/- 44 mm Hg. No significant changes in cardiac output were seen when levels during sinus rhythm (6.4 liters/min), apical pacing (6.4 liters/min) and high septal pacing (5.6 liters/min) were compared. CONCLUSIONS: The right ventricular pacing site is of crucial importance for reducing left ventricular outflow tract obstruction when patients with hypertrophic obstructive cardiomyopathy are treated with pacing. Cardiac output is not reduced by apical pacing.

Adult↗
PubMedDate not supplied

Left ventricular outflow tract obstruction associated with chronic ventricular assist device support.

Favorable long-term patient outcome after insertion of a left ventricular assist device (LVAD) as a bridge to recovery or destination therapy for the treatment of end-stage cardiomyopathy is adversely affected by pathophysiologic changes affecting the heart. Alterations in the native aortic valve apparatus, specifically aortic valve cusp fusion, is an example of such a phenomenon and may especially affect patients in cases of bridge to recovery, a rare but reported event. A retrospective review of the last 33 LVAD placements at our institution was conducted, including reviews of operative reports and pathologic examinations of the native hearts. Seven hearts were found to have varying degrees of aortic valve cusp fusion after chronic LVAD support (63-1, 339 days). Five of these patients had native aortic valves, and two had bioprosthetic valves. The left ventricular outflow tracts in two patients were surgically occluded at the time of LVAD insertion. Aortic valve cusp fusion occurs in roughly 25% of patients on chronic LVAD support. This phenomenon may prove to be clinically significant by creating a potential source of emboli and infection. In addition, in the case of myocardial recovery, left ventricular outflow tract obstruction could limit parallel flow and produce suprasystemic ventricular pressures that in turn would elevate left ventricular end diastolic pressures. The latter may contribute to further myocardial injury, ultimately limiting the ability of an otherwise recovered heart to be weaned from LVAD support.

Adult↗
PubMed2003

Total left ventricular outflow tract obstruction due to left ventricular assist device-induced sub-aortic thrombosis in 2 patients with aortic valve bioprosthesis.

This report describes 2 patients with an aortic bioprosthesis. Both patients developed total thrombotic occlusion of the sub-aortic left ventricular outflow tract consequent to insertion of a left ventricular assist device (LVAD). Replacing a mechanical valve with a bioprosthesis in patients receiving a left ventricular assist device offers no additional protection against thrombosis of the aortic prosthesis. Pericardial patching below the aortic prosthesis at the time of LVAD implantation may be performed, but will significantly impede or prohibit the native ventricle from ejecting blood and demonstrating any degree of recovery.

Adult↗
PubMed1997

Left ventricular outflow tract obstruction due to a left ventricular myxoma: a case report and review of the literature.

A 17-year-old-man who presented with syncope, had a left ventricular (LV) myxoma causing left ventricular outflow tract obstruction. The tumor was removed through left ventriculotomy using conventional cardiopulmonary bypass with good result. There have been 47 cases of LV myxoma reported in the world literature since 1957. Most of them are symptomatic (92.7%). Systemic embolism is the most common manifestation (50%) and often leads to death. The surgical removal should be performed urgently. Resection of the mass with limited normal tissue surrounding its pedicle is recommended. There are only three recurrences and five operative deaths.

Adolescent↗
PubMed1993

Congenital left ventricular outflow tract obstruction.

Congenital obstruction of the left ventricular outflow tract remains a significant problem. Obstruction may involve the subvalvar, valvar or supravalvar portion of the aortic valve complex. Congenital valvar stenosis presenting in the neonatal period represents a spectrum of disorders ranging from the hypoplastic left heart syndrome to almost normal hearts. Preoperative echocardiography may allow the selection of infants who are suitable for biventricular repair, with the therapeutic options including open valvotomy and balloon valvotomy, but the determination of the optimal method of treatment will require long term follow up data. Subvalvar obstruction may be discrete or diffuse, and the extent will determine the appropriate therapy. Discrete membranes may be managed by a simple excision while diffuse involvement of the subvalvar region may require a more extensive reconstructive procedure such as the Konno procedure. Supravalvar aortic stenosis is the least common form of aortic stenosis and may be associated with abnormalities of the pulmonary arteries. Treatment is often palliative rather than corrective with all types of congenital left ventricular outflow tract obstruction, and many patients will require reoperations, especially those with valvar and subvalvar obstruction. The lack of long term follow up data for patients treated in the neonatal period makes the choice of an optimal therapy difficult. New methods of valve replacement such as the pulmonary autograft may improve long term results.

Aortic Stenosis, Subvalvular↗
PubMed1991

Pulmonary stenosis with intact ventricular septum: assessment and indication of reconstructive surgery for residual right-ventricular outflow tract obstruction.

If not all of the right ventricular outflow tract obstruction (RVOTO) is removed in the operation for pulmonary stenosis, high right ventricular pressure can sometimes occur afterward. However, it is not easy to assess the amount of RVOTO that is to be removed, and there is no quantifiable method for selecting operative procedures. The aim of this report is to discuss the formulation of a numerical indicator, based on the parameters peak systolic right-ventricular pressure (RVP), systolic systemic arterial pressure (AP), pulmonary valvular orifice size (VS), and body surface area (BSA), from the results obtained in sixty-four open heart surgeries for pulmonary stenosis with intact ventricular septum. A group, in which an outflow tract patch was not used and which had a higher pre-operative RVP/AP ratio, had a tendency to have a correspondingly higher RVP/AP ratio one month after the operation. Most patients with a high RVP/AP ratio one month after the operation showed a significant decrease in this ratio a long time after the operation. But, there were exceptions to this rule where the ratio remained high. Reconstruction of the right ventricular outflow was considered for some patients whose RVP/AP ratios remained high. Reconstruction of the RVOT by using an outflow tract patch worked well for patients with an associated infundibular stenosis. A subannular patch was used for patients with infundibular stenosis, and a transannular patch was used for patients with annular stenosis. The optimal annulus size was such that VS/BSA was not less than 2 cm2/m2. A transannular monocusp patch was applied to an area which was more than 10 mm wide.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed2005

Systolic anterior motion (SAM) of the posterior mitral leaflet: left ventricular outflow tract obstruction in a patient without left ventricular hypertrophy.

Systolic anterior motion (SAM) of the anterior mitral leaflet with mitral-septal contact was generally thought to be a major contributor to dynamic left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopathy. We report an interesting case of SAM of the posterior mitral leaflet in a patient without left ventricular hypertrophy, which led to dynamic left ventricular obstruction.

Aged↗
PubMed2004

An unusual cause of left ventricular outflow tract obstruction after mitral valve repair.

Left ventricular outflow tract (LVOT) obstruction caused by systolic anterior motion is a cause of failed mitral valve repair. Intraoperative transesophageal echocardiography has been very helpful in diagnosing problems with mitral valve repairs intraoperatively, allowing immediate correction. We report an unusual cause of LVOT obstruction attributed to prolapse of the annuloplasty ring into the LVOT. Intraoperative hemodynamics were normal, and the diagnosis would not have been made before leaving the operative suite without the transesophageal echocardiography.

Cardiac Surgical Procedures↗
PubMed1990

Repair of transposition of the great arteries with intact ventricular septum and left ventricular outflow tract obstruction.

Repair of transposition of the great arteries in patients with intact ventricular septum and fixed left ventricular outflow tract obstruction has been restricted to atrial baffle procedures, with or without attempts to relieve or bypass the left ventricular outflow obstruction. However, the suboptimal results of these procedures, coupled with excellent functional results with the arterial switch operation in patients without obstruction, has made anatomic correction the goal in repairing these anomalies. We report a technique for the anatomic correction of transposition of the great arteries, intact ventricular septum, and fixed left ventricular outflow tract obstruction. Its consideration in these difficult cases is advocated.

Child↗
PubMed2000

Critical left ventricular outflow tract obstruction due to accessory mitral valve tissue.

Left ventricular outflow tract (LVOT) obstruction due to anomalous tissue tag arising from the mitral valve is a rare congenital cardiac anomaly. It generally becomes symptomatic during the first decade of life as exercise intolerance, chest pain, or syncope at effort. To date, only a few cases of critical systemic obstruction due to isolated mitral valve anomaly in neonates have been reported. We report the case of a neonate who was a few hours old and was referred in severe clinical condition due to critical left ventricular outflow obstruction resulting from an anomalous tissue tag of mitral valve origin.

Blood Flow Velocity↗
PubMed2003

Effect of left ventricular outflow tract obstruction on clinical outcome in hypertrophic cardiomyopathy.

BACKGROUND: The influence of left ventricular outflow tract obstruction on the clinical outcome of hypertrophic cardiomyopathy remains unresolved. METHODS: We assessed the effect of outflow tract obstruction on morbidity and mortality in a large cohort of patients with hypertrophic cardiomyopathy who were followed for a mean (+/-SD) of 6.3+/-6.2 years. RESULTS: Of the 1101 consecutive patients, 273 (25 percent) had obstruction of left ventricular outflow under basal (resting) conditions with a peak instantaneous gradient of at least 30 mm Hg. A total of 127 patients (12 percent) died of hypertrophic cardiomyopathy, and 216 surviving patients (20 percent) had severe, disabling symptoms of progressive heart failure (New York Heart Association [NYHA] functional class III or IV). The overall probability of death related to hypertrophic cardiomyopathy was significantly greater among patients with outflow tract obstruction than among those without obstruction (relative risk, 2.0; P=0.001). The risk of progression to NYHA class III or IV or death specifically from heart failure or stroke was also greater among patients with obstruction (relative risk, 4.4; P<0.001), particularly among patients 40 years of age or older (P<0.001). Age-adjusted multivariate analysis confirmed that outflow tract obstruction was independently associated with an increased risk of both death related to hypertrophic cardiomyopathy (relative risk, 1.6; P=0.02) and progression to NYHA class III or IV or death from heart failure or stroke (relative risk, 2.7; P<0.001). The likelihood of severe symptoms and death related to outflow tract obstruction did not increase as the gradient increased above the threshold of 30 mm Hg. CONCLUSIONS: In patients with hypertrophic cardiomyopathy, left ventricular outflow tract obstruction at rest is a strong, independent predictor of progression to severe symptoms of heart failure and of death.

Adult↗
PubMed1987

Extended aortic root replacement for treatment of left ventricular outflow tract obstruction.

Recurrent tunnel stenosis of the left ventricular outflow tract following operation for subaortic stenosis and hypoplastic aortic annulus remain a challenge for pediatric cardiac surgeons. We have recently applied a new technique of extended aortic root replacement using an aortic allograft to treat three patients who had previously been operated upon for subaortic stenosis and three who had aortic stenosis with a hypoplastic aortic annulus. This new procedure combines the concept of aortoventriculoplasty with allograft aortic root replacement and coronary artery reimplantation. The valved aortic homograft is used in place of an aortic valve prosthesis and the attached anterior mitral leaflet augments the interventricular septum to relieve the subvalvular left ventricular outflow tract obstruction. The coronary ostia are then reimplanted into the allograft and distal graft to ascending aorta anastomosis completed. Allograft aortic tissue is then used to patch the right ventricular outflow tract. There have been no operative or late deaths. One patient developed Serratia marcescens mediastinitis but recovered uneventfully after mediastinal drainage. Two cases of transient complete heart block reversed spontaneously. A patient with type II hyperlipidemia developed postpericardiotomy syndrome early, which resolved but then required reoperation at six months for stenosis of the distal anastomosis and left main coronary stenosis, both thought to be complications of his underlying disease. Completely benign convalescence and early follow-up has occurred in the last two patients. This modified technique using aortic allograft was very helpful in treating these difficult problems, and the lack of mortality, limited morbidity, and good function results are encouraging.

Adolescent↗
PubMed1991

Left ventricular outflow tract obstruction from mitral prosthesis.

A case of left ventricular outflow tract obstruction six years following mitral valve replacement is presented. Clinical features, echocardiographic and angiographic studies preoperatively all suggested aortic valve disease. The diagnosis of left ventricular outflow tract obstruction by the strut of the mitral prosthesis was made intraoperatively. Enlargement of the aortic root and aortic valve replacement resulted in good symptomatic and echocardiographic improvement.

Aged↗
PubMed1993

Rapid ventricular pacing in dogs with right ventricular outflow tract obstruction: insights into a mechanism of sudden death in postoperative tetralogy of Fallot.

OBJECTIVES: We explored the hypothesis that residual outflow tract obstruction and ventricular hypertrophy associated with rapid ventricular rhythm contribute to sudden death, in part because they result in humoral or hemodynamic changes that predispose to ventricular fibrillation, such as increased catecholamine release or decreased coronary flow, or both. BACKGROUND: Ventricular arrhythmia after surgical repair of tetralogy of Fallot has been associated with sudden death, particularly in patients with residual right ventricular hypertension. However, the mechanisms by which sudden death occurs remain unclear. METHODS: Seven awake, unanesthetized mature beagles with chronically elevated right ventricular pressure (high pressure group: right ventricular/left ventricular systolic pressure ratio > 0.5) were compared with six beagles with low right ventricular pressure at rest and at the end of 5 min of ventricular pacing at 240 beats/min (low pressure group). RESULTS: In the high pressure group, cardiac output decreased during ventricular pacing (compared with sinus rhythm) from 304 +/- 21 to 218 +/- 21 ml/min per kg (p < 0.01) and plasma norepinephrine increased substantially from 673 +/- 64 to 1,047 +/- 92 pg/ml (p < 0.01). Comparable changes were not observed in the low pressure group. Plasma epinephrine levels were similar in both groups at rest and did not change with pacing. Postpacing norepinephrine levels from both groups correlated positively with both right ventricular systolic and diastolic pressure at rest and correlated negatively with the change in cardiac output from rest to pacing. Regional right ventricular myocardial blood flow increased with pacing in the low pressure group, whereas in the high pressure group it was increased at rest and did not increase further with pacing. CONCLUSION: During ventricular pacing, dogs with right ventricular outflow tract obstruction and high right ventricular pressure had a decrease in cardiac output and an increase in plasma norepinephrine, coupled with a loss of right ventricular myocardial blood flow reserve. Similar changes may occur in postoperative patients with similar hemodynamics and tachyarrhythmia and could contribute to the occurrence of ventricular fibrillation and sudden death.

Animals↗