Neo-aortic valvar function after the arterial switch

OBJECTIVES: The purpose of our study was to assess the prevalence and progression, during childhood and adolescence, of dilation of the neo-aortic root, and neo-aortic valvar regurgitation, and to identify risk factors for such dilation and regurgitation, after the arterial switch operation. METHODS: We included all patients who had undergone an arterial switch operation at The Children's Hospital of Philadelphia, and had been followed for a minimum of 4 years, and had at least 2 postoperative echocardiograms. Neo-aortic valvar regurgitation was quantitatively assessed, and measurements were made of the neo-aortic root at the level of the basal attachment of the leaflets, mid-sinusal level, and the sinutubular junction. RESULTS: We found 82 patients who satisfied the criterions for inclusion, of whom 52 patients had transposition with an intact ventricular septum, and 30 had either an associated ventricular septal defect or double outlet right ventricle. The median follow-up time was 8.8 years (4.1 to 16.4 years). The neo-aortic valve had been replaced in 1 patient. Of the patients, 3 had moderate, 66 had trivial to mild, and 12 had no neo-aortic valvar regurgitation at their most recent follow-up. The regurgitation had progressed by at least 1 grade in 38 of the 82 patients (46.4%). Neo-aortic dilation was noted at the basal attachment of the leaflets, and at mid-sinusal level, which was out of proportion to somatic growth. CONCLUSIONS: At mid-term follow-up, significant neo-aortic valve regurgitation is present in 3.7%, and trivial to mild regurgitation in 81.4% of patients. The regurgitation progressed in almost half of the patients over time. We also noted progressive dilation of the neo-aortic root out of proportion to somatic growth.     

The relationship between neo-aortic root dilation, insufficiency, and reintervention following the Ross procedure in infants, children, and young adults.

OBJECTIVES: The purpose of this study was to describe the relationship between neo-aortic root size, neo-aortic insufficiency (AI), and reintervention at mid-term follow-up. BACKGROUND: Data on neo-aortic valve function and growth after the Ross procedure in children are limited. METHODS: A total of 74 of 119 Ross patients from January 1995 to December 2003 had > or =2 follow-up echocardiograms at our institution and were included. Neo-aortic dimensions were converted to z-scores and modeled over time. Kaplan-Meier analysis was used to assess freedom from neo-aortic outcomes, and predictors were identified through multivariate analysis. RESULTS: Median age at Ross was 9 years (range 3 days to 34 years). Over 4.7 years (range 3 months to 9.3 years) follow-up, there was disproportionate enlargement of the neo-aortic root (z-score increase of 0.75/year [p < 0.0001]). Neo-AI progressed > or =1 grade in 36% of patients and > or =2 grades in 15%. Nine patients (12%) had neo-aortic reintervention at 2.0 years (range 1.1 to 9.5 years) after the Ross procedure owing to severe neo-AI (n = 7), neo-aortic root dilation (n = 1), and neo-aortic pseudoaneurysm (n = 1). At 6 years after the Ross procedure, freedom from neo-aortic reintervention was 88%. Freedom from neo-aortic root z-score >4 was only 3% and from moderate or greater neo-AI was 60%. Longer follow-up time was associated with neo-aortic root dilation (p < 0.0001). Prior ventricular septal defect (VSD) repair predicted neo-AI (p = 0.02) and reintervention (p = 0.03). Prior aortic valve replacement (p = 0.002) also predicted neo-AI. Neo-aortic root dilation was not associated with neo-AI or reintervention. CONCLUSIONS: At mid-term follow-up after the Ross procedure, neo-aortic root size increases significantly out of proportion to somatic growth, and neo-AI is progressive. Prior VSD repair and aortic valve replacement were associated with neo-AI and reintervention.     

Changes in size of ascending aorta and aortic valve function with time in patients with congenitally bicuspid aortic valves

Bicuspid aortic valve (BAV) is associated with premature valve dysfunction and abnormalities of the ascending aorta. Limited data exist regarding serial changes of aortic dilation in patients with BAV. We studied paired transthoracic echocardiograms of 68 patients with BAV (mean age 44 years) and with at least 2 examinations >12 months apart (mean follow-up 47 months) to characterize the progression of aortic dilation and the natural history of valve function. We measured aortic root and ascending aortic diameters at baseline and follow-up. We measured aortic gradients and severity of aortic regurgitation (AR). During follow-up, aortic diameters increased at the sinuses of Valsalva by 1.9 mm (95% confidence interval [CI] 1.3 to 2.5), at the sinotubular junction by 1.6 mm (95% CI 0.8 to 2.3), and at the proximal ascending aorta by 2.7 mm (95% CI 1.9 to 3.6). Mean rate of diameter progression was 0.5 mm/year at the sinuses of Valsalva (95% CI 0.3 to 0.7), 0.5 mm/year at the sinotubular junction (95% CI 0.3 to 0.7), and 0.9 mm/year at the proximal ascending aorta (95% CI 0.6 to 1.2). Progression was observed regardless of hemodynamic function at baseline. Mean aortic valve gradient increased significantly from baseline to follow-up (17.6 mm Hg vs 25.7 mm Hg, p <0.001). The degree of AR increased during follow-up in 17 patients (25%). In addition, progression of aortic diameter dilation occurred irrespective of baseline valve function in adult patients with BAV. We also observed considerable progression of aortic gradients and AR over time.     

Management of Patients With Bicuspid Aortic Valve Disease

Our approach to the management of the patient with a bicuspid aortic valve (BAV) takes several factors into consideration. First, is the dysfunction of the valve due to aortic stenosis (AS), aortic regurgitation (AR), or a combination of stenosis and regurgitation, and what is the severity? Next, is there aortic dilation in any of the regions (sinuses of Valsalva, sinotubular junction, tubular ascending aorta, or transverse arch) discussed in this article. In general, we follow patients with a BAV and moderate valve dysfunction (AS or AR) with yearly surveillance transthoracic echocardiography for left ventricular function, jet velocity, gradient, and valve area with AS, whereas left ventricular (LV) function and LV dimensions are monitored for patients with AR. In addition, yearly clinical evaluation for change in symptom status or functional capacity is critical. More recently, we have utilized NT-pro BNP levels to help assess patients, particularly those in whom the anatomic severity does not match the clinical symptoms (ie, the valve severity appears mild but the patient is complaining of symptoms or the valve severity seems significant but no symptoms are noted). All patients with a bicuspid valve should have evaluation of the aorta with a MRI or CT angiography at some point, as 50% of BAV patients have aortic root involvement. At our institution, cardiac MRI is preferred unless there is a contraindication, particularly in younger patients, given the cumulative radiation exposure from surveillance CT scans. Cardiac MRI also provides the added benefit of information regarding LV function, LV dimensions, and assessment of valve stenosis/regurgitation severity, thus obviating the need for echocardiographic data in those being followed with serial cardiac MRI. For those with no aortic dilatation, we tend to use only echocardiography for follow-up. For patients with mild aortic dilation, surveillance aortic imaging is usually performed every 3–5 years. However, for those with greater degrees of aortic dilation (aortic diameters >4.0 cm) or notable interval change in dimensions, then aortic imaging every year is conducted. For young adult patients with isolated aortic stenosis, balloon aortic valvuloplasty is often an effective and temporizing treatment option. In older patients with aortic stenosis or those with AR, aortic valve replacement, with or without a surgery on the aorta depending on whether concomitant dilation (aortic diameter >4.5 cm) of the aorta is present, is the preferred management strategy. In a few patients, surgery on the aortic alone may be indicated if the maximal diameter exceeds 5.0 cm.     

Long-term results after repair of truncus arteriosus communis in neonates and infants

BACKGROUND: We reviewed our experience of truncus arteriosus communis (TAC) repair. METHODS: Between 05/90 and 10/01, 16 patients underwent complete repair of TAC (primary repair: group I, 12 patients, secondary repair: group II, 4 patients). Age was 2.4 months [5 days-8.8 months] (median [range]) in group I, and 8.3 [5.6-13.5] years in group II. Continuity from the right ventricle to the pulmonary artery was achieved using a valved conduit. All patients had regular follow-up examinations. RESULTS: There was one early death in each group (12.5%). Follow-up was 9 [1.2-12.7] years. Valved conduit failure occurred in 8 patients (67 %) in group I (group II, 1 patient, 33 %) requiring replacement at 2.5 [0.3-4.3] years (group II, 5.8 years). Severe neo-aortic valve regurgitation after truncal valve repair was observed in one patient, requiring valve replacement at 8.5 years in association with repeat homograft replacement (group I). Actual echocardiographic examination revealed normal ventricular function. Moderate conduit dysfunction was noted in 2 patients (group I). CONCLUSIONS: Complete repair of truncus arteriosus communis can be performed with excellent long-term results.     

Serial echocardiographic assessment of neo-aortic regurgitation and root dimensions after the modified Ross procedure

BACKGROUND AND AIM OF THE STUDY: Concern exists regarding progressive root dilatation after the modified Ross procedure. The present prospective echocardiographic study aimed to provide further insight into neo-aortic regurgitation (nAR) and neoaortic root dimensions over time in adult Rotterdam Ross root patients, and to study potential risk factors for nAR and dilatation. METHODS: All Rotterdam Ross patients aged > or = 16 years at surgery were subjected to a prospective biennial standardized echocardiographic protocol. Analysis over time of nAR according to the jet length and jet diameter method, autograft annulus and sinotubular junction (STJ) diameters was carried out using a multilevel linear model in 90 patients who had two or more echocardiographic measurements (mean 5; range 2-9; total 458) up to 14 years (mean 7 years) after surgery. RESULTS: The mean (+/- SE) initial postoperative jet length nAR was grade 0.9 +/- 0.09, and the annual increase 0.1 +/- 0.02 (p < 0.001). Initial annulus and STJ diameters were 25 +/- 0.5 mm and 36 +/- 0.6 mm, while annual increases were 0.4 +/- 0.07 mm and 0.5 +/- 0.09 mm, respectively (p < 0.001). Patients who eventually underwent an autograft reoperation (n = 10) had significantly greater initial nAR and greater progression of nAR, and a greater initial annulus diameter. The annual annulus and STJ diameter increase was greater in patients who underwent autograft reoperation. Compared to freestanding root replacement, patients with inclusion cylinder aortic root replacement had smaller initial annulus and STJ diameters that did not increase over time. Female gender was associated with a greater initial jet length and jet diameter nAR and a greater increase over time in jet diameter nAR. Preoperative aortic regurgitation or combined aortic stenosis and regurgitation were associated with greater initial annulus and STJ diameters. Neither bicuspid valve disease, patient age, preoperative ascending aorta aneurysm, prior aortic valve surgery nor hypertension had an effect on initial or progression of nAR, annulus, and STJ diameter. CONCLUSION: The annual increase in nAR and root dimensions is small, but persistent, after autograft aortic root replacement in adults, and further reoperations should be anticipated. Use of the inclusion cylinder root replacement technique seems to prevent neo-aortic dilatation.     

Pulmonary autograft replacement of the bicuspid aortic valve: a successful surgical option for young adults

A severely dysfunctioning congenitally bicuspid aortic valve may require surgical treatment within the fourth decade of life. Among conventional options, the pulmonary autograft (PA) offers many theoretical advantages particularly for young patients, including potential for growth, hemodynamic performance, no need for anticoagulants and freedom from endocarditis. However the operation is more complex and longer, may interfere with coronary and right ventricular anatomy and function and may expose the patient to the downside of two valves at risk. Aim of this retrospective study was to evaluate the mid-term results achieved with the PA performed in adolescents and young adults with a bicuspid aortic valve. Between July 94 and June 98, 26 patients, 22 males and four females, with a mean age of 24+/-10 years (range, 11 to 38), underwent bicuspid aortic valve replacement with a pulmonary autograft (stenosis 2-8%; insufficiency 13-50%; combined 11-42%). Eight patients (31%) were in NYHA FC I, 17 (65%) in II, and 1 (4%) in III. Mean preoperative ejection fraction was 67+/-7%. Three patients (11.5%) had a past medical history of endocarditis (healed in all) and in two the PA was a re-do procedure. The PA was inserted as a subcoronary implant in one case (4%) and utilized as a root in the remaining 25 (96%). The right ventricular outflow tract was reconstructed with a cryopreserved pulmonary homograft conduit in all cases. Mean cardiopulmonary bypass and aortic crossclamp times were 204+/-50 min (range, 174 to 300) and 157+/-35 min (range, 133 to 193) respectively. No early or late deaths had occurred at a mean follow-up of 22.5 months (range, 5 to 47.5). The first patient in the series (4%) was reexplored for bleeding and needed transfusions. The subsequent routine use medical and surgical strategies resulted in no further need for postoperative reexploration, and successful containment of total postoperative blood loss (<350 ml/m2BSA). 2-D Echo evaluation of neo-aortic valve competence at 6 months, revealed no evidence of aortic valve regurgitation in 17 (65%), trivial regurgitation in seven (27%), mild in one (4%) and mild-to-moderate in one (4%). The latter patient (subcoronary implant PA) required reoperation. At six months, the mean degree of regression of left ventricular mass compared to pre-operative data, was 36% (333+/-94 to 212+/-60 gr, p<0.05). All patients are asymptomatic, in NYHA FC I, and enjoy normal social interaction. In conclusion, PA root implantation can be offered as a low-risk alternative to conventional prosthetic aortic valve replacement to adolescents and young adults with a bicuspid aortic valve. The routine achievement of blood loss containment has minimized the risk of transfusion thus contributing to expand the indication in young patients. Continued patients evaluation particularly with regard to evidence of neo-aortic valve degeneration, root dilatation and homograft dysfunction in the long term is warranted.     

Successful Pregnancies in Two Women with Hypoplastic Left Heart Syndrome

Objective. Hypoplastic left heart syndrome (HLHS) is a relatively common complex congenital heart defect. Prior to development of staged reconstruction (i.e., Norwood procedure), HLHS was almost universally fatal within months of birth. Early survivors of the Norwood procedure are now reaching reproductive age. We report successful pregnancies in two such women. Patients. The first patient was a 20-year-old woman transferred from a community hospital at 33 3/7 weeks gestation because of preterm labor, suspected preeclampsia, and mild chronic hypoxemia. She had normal systemic ventricular shortening without significant valvar regurgitation but severe neoaortic dilatation. A fetal ultrasound demonstrated intrauterine growth restriction. An urgent Cesarean section was performed at 33 6/7 weeks gestation, given breech position and intractable preterm labor. The second patient, a 23-year-old woman followed at this institution through pregnancy, presented with preterm labor at 36 weeks gestation. Her systemic ventricular shortening was normal, with mild tricuspid regurgitation but without neoaortic dilation or regurgitation. She developed active labor at 36 3/6 weeks, and had a spontaneous vaginal delivery of a small for gestational age infant. Both women tolerated labor and childbirth without complication. Neither infant had evidence of structural heart disease on fetal echocardiography or physical examination. Conclusions. These cases, the first reported successful pregnancies in mothers with HLHS, highlight the challenges of pregnancy among women with complex congenital heart disease in general and raise several considerations specific to HLHS.     

Progressive dilation of the diameter of the aortic root in adults with a bicuspid aortic valve

BACKGROUND: To determine the rate of progression of dilation of the aortic root in adults with a bicuspid aortic valve. METHODS: We reviewed retrospectively the transthoracic echocardiograms of 50 adults with a bicuspid aortic valve. Each patient had had at least two examinations made 12 months apart. Measurements were taken at four levels: at the basal attachment of the leaflets of the valve within the left ventricular outflow tract, at the widest point of the sinuses of Valsalva, at the sinutubular junction, and in the ascending aorta 1 cm beyond the sinutubular junction. RESULTS: Progressive dilation occurred at all levels, ranging from 0.3 mm/yr at the basal attachment within the left ventricular outflow tract to 1.0 mm/yr, 1 cm beyond sinutubular junction. These rates of dilation were greater than the reported rate of 0.8 mm per decade in the normal population. The rate of dilation found in the ascending aorta 1 cm beyond the sinutubular junction was significantly greater than at the other sites (p = 0.005). The 21 patients with baseline measurements greater than 34 mm had a significantly higher rate of progression (p = 0.007). Sex, age, and the degree of valvar obstruction or regurgitation did not significantly influence the rate of progression of dilation. CONCLUSION: There is a significantly higher rate of dilation of the aortic root in adults with a bicuspid aortic valve when compared to the normal population. Periodic evaluation of the ascending aorta is essential in these patients, even after replacement of the aortic valve. Other imaging modalities should be considered if the region beyond the sinutubular junction is not well visualized by transthoracic echocardiography.     

Aortic root disease and valve disease associated with ankylosing spondylitis

Objectives. This study sought to determine the prevalence, characteristics, relation to clinical features and evolution of aortic root disease and valve disease associated with ankylosing spondylitis (AKS).Background. Aortic root disease and valve disease are common in patients with AKS, but their clinical and prognostic implications have not been well defined.Methods. Forty-four outpatients with AKS and 30 age- and gender-matched healthy volunteers underwent initial transesophageal echocardiography and rheumatologic evaluations. Twenty-five patients underwent clinical and echocardiographic follow-up 39 ± 10 months later.Results. Aortic root disease and valve disease were common in patients (82%) as compared with controls (27%; p < 0.001). Aortic root thickening, increased stiffness and dilatation were seen in 61%, 61% and 25% of patients, respectively. Valve thickening (41% for the aortic and 34% for the mitral valve) manifested predominantly (74%) as nodularities of the aortic cusps and basal thickening of the anterior mitral leaflet, forming the characteristic subaortic bump. Valve regurgitation was seen in almost half of patients, and 40% had moderate lesions. Except for the duration of AKS, aortic root disease and valve disease were unrelated to the activity, severity or therapy of AKS. During follow-up of 25 patients, in up to 24% new aortic root or valve abnormalities developed, in 12% existing valve regurgitation worsened significantly and in 20% abnormalities resolved. Twenty percent of patients developed heart failure, underwent valve replacement, had a stroke or died, as compared with 3% of control subjects.Conclusions. Aortic root disease and valve disease are common in patients with AKS, are unrelated to clinical features of AKS, can resolve or progress over time and are associated with clinically important cardiovascular morbidity.     

Color flow and conventional echocardiography of the Marfan syndrome

Imaging and color flow Doppler echocardiography are an integral part of any evaluation of a patient with the Marfan syndrome. The major cardiovascular manifestations of this condition are aortic dilation, which may involve the proximal and distal aorta, aortic regurgitation, aortic dissection, mitral valve prolapse, and mitral regurgitation. Patients who have the Marfan syndrome should have serial echocardiograms to measure aortic root diameter carefully at the sinuses of Valsalva and subsequent levels (sinotubular junction, arch, descending and abdominal aorta). Additionally, color Doppler echocardiography assists in the diagnosis of aortic dissection and facilitates evaluation of the severity of aortic and mitral regurgitation that commonly complicate the Marfan syndrome. The risk of aortic dissection, which is the most serious manifestation of the Marfan syndrome, increases as the aorta enlarges. Therefore, elective composite graft surgery is recommended when the aortic root size reaches 60 mm, regardless of symptom status, or 55 mm in the presence of severe aortic regurgitation. Surgical replacement of the aortic root with a composite graft does not end the disease process. Color flow Doppler is useful in the diagnosis of dehiscence of the conduit sewing ring, coronary artery aneurysm, distal aortic dissections, and prosthetic valve dysfunction.     

Complete transposition of the great arteries: surgical concepts for patients with systemic right ventricular failure following intraatrial repair

One of the most serious late complications of the intraatrial baffle procedure (Mustard or Senning correction) in patients suffering from transposition of the great arteries, (TGA) is the late systemic right ventricular failure. Nearly all patients presenting with right ventricular dysfunction have severe associated tricuspid regurgitation. The surgical options for these patients include tricuspid valve reconstruction or replacement, staged conversion to the arterial switch operation and orthotopic heart transplantation. Review of 189 operative survivors who underwent the Mustard or Senning operation for TGA between 1970 and 1993 in our institution revealed 12 patients (6.3%) who died from severe systemic right ventricular dysfunction (mean follow-up 16+/-3.5 years), which was the most common cause of late death. All of them had concomitant severe tricuspid regurgitation. 7 patients (3.7%) died from sudden cardiac death. The actuarial survival at 10 years is 93% for simple TGA and 85% for TGA associated with ventricular septum defect or coarctation. At our institution, 4 adolescent or adult patients underwent tricuspid valve surgery; tricuspid valve replacement was performed in 2 patients and valve repair in 2 patients. In the mid-term follow-up, 2 of these patients died. Two additional patients underwent orthotopic heart transplantation, and one died on the waiting list. Staged conversion from the Senning/Mustard atrial repair to the arterial switch operation was initially reported by Mee. The procedure for pulmonary artery banding starts with inducing left ventricular reconditioning with subsequent arterial switch. The mortality of this two-staged procedure was as high as 20% to 30% in our early experience, and some of the candidates underwent heart transplantation. Tricuspid valve repair or replacement do not improve right ventricular function in patients with a failing right ventricle following the Mustard/Senning operation. Staged conversion to arterial switch may improve right ventricular function by decreasing the work load of the right ventricle and provides anatomic repair with left ventricle-to-aorta continuity. Orthotopic heart transplantation is the only alternative if the left ventricle does not respond to pulmonary artery banding.     

Mitral Regurgitation Associated with Mitral Annular Dilation in Patients with Lone Atrial Fibrillation: An Echocardiographic Study

Background: Whether and how lone atrial fibrillation (AF) is associated with functional mitral regurgitation (MR) remain unclear. Method: We studied 12 lone AF patients without left ventricular (LV) dysfunction and/or dilatation, who underwent mitral valve annuloplasty for functional mitral regurgitation (MR). Ten lone AF patients without MR served as controls. Results: Lone AF Patients with MR had a greater mitral valve annular area and left atrial area than those without MR. There were no differences in LV volumes or LV ejection fraction. Conclusions: Therefore, we concluded that left atrial dilation and corresponding mitral annular dilation may cause MR in lone AF patients without LV dysfunction and/or dilatation.     

Morphology of bicuspid aortic valve in children and adolescents

OBJECTIVES: The aim of this study was to determine the relationship between aortic valve morphology and valve dysfunction. BACKGROUND: The morphology of the bicuspid or bicommissural aortic valve (BAV) may predict the severity of valve dysfunction. Therefore, we assessed the relationship between BAV, aortic coarctation, and the degree of valve pathology in children. METHODS: A retrospective review of 1,135 patients with BAV who were identified between 1986 and 1999 was performed. Patients younger than 18 years of age with BAV that was identifiable via echocardiography were included. The most recent or last study of each patient before intervention or endocarditis was reviewed. Mild stenosis was defined as a valve gradient > or =2 m/s, moderate or greater aortic stenosis as > or =3.5 m/s. Aortic regurgitation was quantified using standard criteria. RESULTS: Median age was 3 years (range, 1 day to 17.9 years), and 67% of the patients were male. Right-coronary and left-coronary leaflet fusion were the most common types of BAV (70%). Aortic stenosis that was moderate or greater was observed most often in patients with right-coronary and non-coronary leaflet fusion (odds ratio 2.4, 95% confidence interval 1.6 to 3.6; p < or = 0.001). Similarly, right-coronary and non-coronary leaflet fusion was more often associated with moderate aortic regurgitation or greater (odds ratio 2.4, 95% confidence interval 1.2 to 4.7; p = 0.01). The majority of patients with aortic coarctation had fusion of the right-coronary and left-coronary leaflets (89%), and aortic coarctation was associated with lesser degrees of valve stenosis or regurgitation. CONCLUSIONS: Analysis of BAV morphology is of clinical and prognostic relevance. Fusion of the right-coronary and non-coronary leaflets was associated with more significant valve pathology, whereas fusion of the right-coronary and left-coronary leaflets was associated overwhelmingly with aortic coarctation and less aortic valve pathology.     

Durability and prevalence of aortic regurgitation nine years after aortic valve replacement with the Toronto SPV stentless bioprosthesis

BACKGROUND AND AIM OF THE STUDY: Stentless aortic bioprostheses have excellent hemodynamics. Previous investigations of the Toronto SPV valve described a correlation between the occurrence of significant aortic regurgitation (AR) and dilation of the sinotubular junction. The study aim was to determine the long-term durability and determinants of AR at nine years in a large, multicenter study of the Toronto SPV valve. METHODS: The study included 447 patients from six centers. Clinical outcomes and echocardiographic data (gradients, effective orifice area index (EOA-I), left ventricular mass, aortic root dimensions, and presence and severity of AR) were collected prospectively. A multivariable logistic regression model was used to evaluate clinical and echocardiographic variables for impact on the occurrence of AR. RESULTS: Total follow up was 2,660 patient-years (mean 6.0 +/- 2.5 years; range: 0 to 11.1 years). Mean gradient and EOA-I remained unchanged through nine years. There were 17 cases of structural deterioration, of which 15 underwent explantation. The mechanism of failure was predominantly leaflet tear in the setting of sinotubular dilation. Freedom from explant for structural failure was 90.1% at nine years (100% for patients aged > or = 65 years). Freedom from hemodynamically significant AR was 96.9% at five years and 82.5% at nine years. Determinants of AR were longer duration of follow up, larger valve size, and increase in the ratio of sinotubular junction to the size of valve implanted. CONCLUSION: At nine years after implantation of the Toronto SPV valve, hemodynamics remained excellent. There was good freedom from structural deterioration through nine years, and structural failure occurred due to aortic root dilation and leaflet tear, without significant valve calcification. AR tends to occur with longer follow up, larger valve sizes, and dilation of the sinotubular junction.     

Results of the arterial switch operation in patients with transposition of the great arteries and abnormalities of the mitral valve or left ventricular outflow tract

Between January 1983 and October 1989, 290 patients underwent an arterial switch operation for transposition of the great arteries; 30 (10.3%) of the patients had abnormalities of the left ventricular outflow tract or mitral valve, or both. These abnormalities included isolated pulmonary valve stenosis (n = 9), septal (dynamic) subpulmonary stenosis (n = 5), anatomic (fixed) subpulmonary stenosis (n = 7), abnormal mitral chordae attachments (n = 2) or a combination of abnormalities (n = 7). There were two early deaths, one of which was due to previously unrecognized mitral stenosis and a subpulmonary (neo-aortic) membrane and one late death due to presumed coronary obstruction. Of the nine patients with pulmonary valve abnormalities due to either a bicommissural (n = 5) or a thickened tricommissural (n = 4) valve, only one underwent valvotomy. Peak systolic ejection gradients in these nine patients measured preoperatively ranged from 0 to 50 mm Hg. At follow-up study 5 to 30 months postoperatively, the neo-aortic valve gradient was less than or equal to 15 mm Hg in all patients; three patients had mild neo-aortic regurgitation. Preoperative gradients may overestimate the degree of obstruction because of the increased pulmonary blood flow present in transposition. No patient with "dynamic" subpulmonary obstruction before the arterial switch operation had a surgical procedure performed on the left ventricular outflow tract; none had evidence of subaortic obstruction after the arterial switch.(ABSTRACT TRUNCATED AT 250 WORDS)     

Determinants of functional tricuspid regurgitation in incomplete tricuspid valve closure: Doppler color flow study of 109 patients

Objectives. The aim of this study was to investigate the association between the pattern of incomplete tricuspid valve closure and the presence of tricuspid regurgitation and to identify factors that determine the severity of regurgitation associated with this pattern.Background. The incomplete tricuspid valve closure pttern (defined as apical displacement of the leaflets) has been described by two-dimensional echocardiography. However, whether this pattern is universally associated with tricuspid regurgitation and the determinants of severity of regurgitation in its presence have not been studied by Doppler color flow mapping.Methods. We identified 109 consecutive patients (mean age 62 ± 17 years) with incomplete tricuspid valve closure who were studied by Doppler color flow mapping. We measured the linear apical displacement of the coaptation point from the tricuspid annulus and the area of displacement between the leaflets and annulus. Right atrial, ventricular and annular dimensions were measured and compared with those in a group of normal subjects.Results. Tricuspid regurgitation was present in all ptients with the incomplete closure pattern; it was mild in 14%, moderate in 19% and severe in 67%. Apical displacement was significantly greater (p < 0.02) in those with severe regurgitation than in those with mild regurgitation or in normal subjects. Tricuspid annulus dilation was the only independent predictor of severity of regurgitation. The right ventricle was not significantly dilated in 32% of patients, and right ventricular systolic pressure was not correlated with the severity of regurgitation and was <30 mm Hg in 11% of patients.Conclusions. Tricuspid regurgitation was associated with incomplete tricuspid valve closure in all patients studied and was moderate to severe in 86%. Impaired coaptation is best reflected by the displacement area between the leaflets and the annulus. High pulmonary pressure and significant right ventricular dilation are not prerequisites for functional tricuspid regurgitation. Annular dilation is the most consistent and important determinant of this lesion.     

Mitral valve surgery in patients with poor left ventricular function

BACKGROUND: Mitral valve surgery for the correction of secondary mitral valve regurgitation (MR) in cardiomyopathy is associated with a poor outcome. Numerous studies have identified a severe left ventricular dysfunction as an indicator for a poor prognosis. The aim of the study was to asses the follow-up after mitral valve surgery and severe left ventricular dysfunction. METHODS: Between 1994 and 2000, 31 patients with mitral regurgitation and a left ventricular ejection fraction of below thirty percent undergoing isolated repair (n = 16) or replacement (n = 15) were investigated. All patients received maximal drug therapy. Twenty-one patients were New York Heart Association (NYHA) class III and 10 were class IV. Follow-up with echocardiography, ECG, and chest x-ray was performed in 87 % of the survivors. The mean duration of follow-up was 39 +/- 16 months. RESULTS: The mean duration of ICU and hospital stay was 3.6 +/- 2.1 days and 8.1 +/- 5.4 days, respectively. The 1-, 2-, and 5-year survival rates were 91 %, 84 %, and 77 %, respectively. NYHA class improved from 3.3 +/- 0.8 to 2.1 +/- 0.7 at follow-up (p < 0.01). The ejection fraction improved from 23.1 +/- 6.6 % to 36 +/- 6.8 % at follow-up (p < 0.02). Freedom from readmission for heart failure was 85 %, 79 %, and 68 % at 1-, 2-, and 5 years, respectively. CONCLUSIONS: Mitral valve surgery improves left ventricular function and reduces heart failure severity in patients with MR and cardiomyopathy. High-risk mitral valve surgery may be an alternative to heart transplantation in selected patients.     

Valvular aortic stenosis: disease severity and timing of intervention

Standard echocardiographic evaluation of aortic stenosis (AS) severity includes measurement of aortic velocity, mean transaortic pressure gradient, and continuity equation valve area. Although these measures are adequate for decision making in most patients, there is no single value that defines severe stenosis. Aortic stenosis affects not just the valve, but the entire vascular system, including the left ventricle (LV) and systemic vasculature. More sophisticated measures of disease severity might explain the apparent overlap in hemodynamic severity between symptomatic and asymptomatic patients and might better predict the optimal timing of valve replacement. There have been several approaches to evaluation of stenosis severity based on valve hemodynamics, the ventricular response to increased afterload, ventricular-vascular coupling, or the systemic functional consequences of valve obstruction, such as exercise testing and serum brain natriuretic peptide levels. Aortic valve replacement is indicated when symptoms due to severe AS are present. In most asymptomatic patients, the risk of surgery is greater than the risk of watchful waiting so that management includes patient education, periodic echocardiography, and cardiac risk factor modification. Many adults with AS have comorbid conditions that affect both the diagnosis and management of the valve disease, including aortic regurgitation, aortic root dilation, hypertension, coronary artery disease, LV dysfunction, and atrial fibrillation. Comorbid conditions should be evaluated and treated based on established guidelines, although awareness of the potential effects of therapy in the presence of valve obstruction is needed.     

Valvular aortic stenosis: disease severity and timing of intervention.

Standard echocardiographic evaluation of aortic stenosis (AS) severity includes measurement of aortic velocity, mean transaortic pressure gradient, and continuity equation valve area. Although these measures are adequate for decision making in most patients, there is no single value that defines severe stenosis. Aortic stenosis affects not just the valve, but the entire vascular system, including the left ventricle (LV) and systemic vasculature. More sophisticated measures of disease severity might explain the apparent overlap in hemodynamic severity between symptomatic and asymptomatic patients and might better predict the optimal timing of valve replacement. There have been several approaches to evaluation of stenosis severity based on valve hemodynamics, the ventricular response to increased afterload, ventricular-vascular coupling, or the systemic functional consequences of valve obstruction, such as exercise testing and serum brain natriuretic peptide levels. Aortic valve replacement is indicated when symptoms due to severe AS are present. In most asymptomatic patients, the risk of surgery is greater than the risk of watchful waiting so that management includes patient education, periodic echocardiography, and cardiac risk factor modification. Many adults with AS have comorbid conditions that affect both the diagnosis and management of the valve disease, including aortic regurgitation, aortic root dilation, hypertension, coronary artery disease, LV dysfunction, and atrial fibrillation. Comorbid conditions should be evaluated and treated based on established guidelines, although awareness of the potential effects of therapy in the presence of valve obstruction is needed.