The progression of mild congenital aortic valve stenosis from childhood into adult life

Congenital aortic valve stenosis: from pathophysiology to molecular genetics and the need for novel therapeutics

Congenital aortic valve stenosis (AVS) is one of the most common valve anomalies and accounts for 3%-6% of cardiac malformations. As congenital AVS is often progressive, many patients, both children and adults, require transcatheter or surgical intervention throughout their lives. While the mechanisms of degenerative aortic valve disease in the adult population are partially described, the pathophysiology of adult AVS is different from congenital AVS in children as epigenetic and environmental risk factors play a significant role in manifestations of aortic valve disease in adults. Despite increased understanding of genetic basis of congenital aortic valve disease such as bicuspid aortic valve, the etiology and underlying mechanisms of congenital AVS in infants and children remain unknown. Herein, we review the pathophysiology of congenitally stenotic aortic valves and their natural history and disease course along with current management strategies. With the rapid expansion of knowledge of genetic origins of congenital heart defects, we also summarize the literature on the genetic contributors to congenital AVS. Further, this increased molecular understanding has led to the expansion of animal models with congenital aortic valve anomalies. Finally, we discuss the potential to develop novel therapeutics for congenital AVS that expand on integration of these molecular and genetic advances.

Monocyte-to-HDL-cholesterol ratio is associated with Ascending Aorta Dilatation in Patients with Bicuspid Aortic Valve

BACKGROUND

The importance of monocyte count-to-HDL-cholesterol ratio (MHR) in cardio- vascular diseases has been shown in various studies. Ascending aortic dilatation (AAD) is a common complication in the patients with bicuspid aortic valve. In this study, we aimed to investigate the relationship between MHR and the presence of aortic dilatation in the patients with bicuspid aortic valve.

METHODS

The study population included totally 347 patients with bicuspid aortic valve.169 patients with aortic dilatation (ascending aorta diameter ≥ 4.0 cm) and 178 patients with no aortic dilatation. Echocardiographic and laboratory measurement was done and compared between groups.

RESULTS

The mean age of the participants was 44.7 ± 15.4 years and average ascending aorta diameter was 3.2 ± 0.3 cm in dilatation negative group and 4.4 ± 0.4 cm in positive group. MHR was significantly increased in in patients with aortic dilatation. MHR and uric acid level was independently associated with the presence of aortic dilatation in the patients with bicuspid aortic valve.

CONCLUSION

We found a significant relationship between MHR and aortic dilatation in the patients with bicuspid aortic valve.

EDUCATIONAL SERIES IN CONGENITAL HEART DISEASE: Congenital left-sided heart obstruction

Congenital obstruction of the left ventricular outflow tract remains a significant problem and multilevel obstruction can often coexist. Obstruction can take several morphological forms and 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. Treatment options vary dependent on the severity of the left ventricular outflow tract obstruction (LVOTO) and the variable degree of left ventricular hypoplasia as well as the associated lesions such as arch hypoplasia and coarctation.

Higher neutrophil to lymphocyte ratio is related to a lower ejectionfraction in bicuspid aortic valve patients

BACKGROUND/AIM

Inflammation plays an important role in the pathophysiology of vascular disease. In this study, we aimed to evaluate the associations of neutrophil to lymphocyte ratio (NLR; an indicator of inflammation) with left ventricular ejection fraction and ascending aorta diameter in patients with a bicuspid aortic valve (BAV).

MATERIALS AND METHODS

One hundred and thirty-nine consecutive patients with the diagnosis of BAV were enrolled in the study. Complete blood counts were analyzed for neutrophil and lymphocyte levels and NLR. The subjects were separated into two groups based on their ascending aorta diameter. The patients with ascending aorta diameter equal to or above 3.9 cm were included in group 1 whereas those with ascending aorta diameter below 3.9 cm were included in group 2.

RESULTS

When the results were compared, it was demonstrated that there was a positive correlation between NLR and ascending aorta diameter (r: 0.485, P = 0.026), whereas there was a negative correlation between NLR and left ventricular end-diastolic diameter (r: 0.475, P = 0.030), left ventricular end-systolic diameter (r: 0.482, P = 0.027), and left ventricular ejection fraction (r: -0.467, P = 0.033) in BAV patients with ascending aorta dilatation (group 1).

CONCLUSION

NLR is associated with ascending aorta diameter and left ventricular ejection fraction in BAV patients with ascending aorta dilatation.

Percutaneous Balloon Valvuloplasty for Aortic Stenosis in Newborns and Children

In all cases of congenital valvar aortic stenosis (AS), reduced effective orifice area leads to obstruction to flow, usually resulting from thickening and reduced motion of the valve leaflets. The most severe cases of valvar AS present soon after birth, with low cardiac output secondary to left ventricular dysfunction. Interventional treatment options consist of open surgical valvotomy or balloon valvuloplasty, with both therapies providing excellent but usually only temporary relief of stenosis. This article focuses on balloon aortic valvuloplasty as a therapy for congenital valvar AS in infants and children, focusing on established techniques, outcomes, and future challenges.

Bicuspid aortic valve disease

Bicuspid aortic valve (BAV) disease is the most common congenital cardiac defect. While the BAV can be found in isolation, it is often associated with other congenital cardiac lesions. The most frequent associated finding is dilation of the proximal ascending aorta secondary to abnormalities of the aortic media. Changes in the aortic media are present independent of whether the valve is functionally normal, stenotic, or incompetent. Although symptoms often manifest in adulthood, there is a wide spectrum of presentations ranging from severe disease detected in utero to asymptomatic disease in old age. Complications can include aortic valve stenosis or incompetence, endocarditis, aortic aneurysm formation, and aortic dissection. Despite the potential complications, 2 large contemporary series have demonstrated that life expectancy in adults with BAV disease is not shortened when compared with the general population. Because BAV is a disease of both the valve and the aorta, surgical decision making is more complicated, and many undergoing aortic valve replacement will also need aortic root surgery. With or without surgery, patients with BAV require continued surveillance. Recent studies have improved our understanding of the genetics, the pathobiology, and the clinical course of the disease, but questions are still unanswered. In the future, medical treatment strategies and timing of interventions will likely be refined. This review summarizes our current understanding of the pathology, genetics, and clinical aspects of BAV disease with a focus on BAV disease in adulthood.

Bicuspid Aortic Valve Morphology and Interventions in the Young

OBJECTIVES

The aim of this study was to determine whether the morphologic subtype of bicuspid aortic valve (BAV) is associated with valve intervention in the young.

BACKGROUND

Analysis of BAV morphology is of prognostic relevance, as the fusion of right- and noncoronary leaflets (R-N) is associated with a greater degree of valve dysfunction compared with other subtypes. However, it is currently unknown whether morphologic differences translate into clinically relevant outcomes such as valve intervention.

METHODS

A nested cohort study was conducted on 310 patients with right- and left-coronary leaflet (R-L) and R-N fusion who were selected randomly from an inception cohort of 1,192 patients with BAV who were identified between 1986 and 1999. Supplementary information on clinical parameters was collected retrospectively from medical charts and databases.

RESULTS

Median age at follow-up was 16.1 years (range 5.6 to 34.4 years), and 71% were male. The R-N fusion (n = 108) was strongly predictive of valve intervention when compared with The R-L fusion (n = 202; hazard ratio 4.5, 95% confidence interval [CI] 2.5 to 8.1; p < 0.0001). In a longitudinal analysis of 799 echocardiograms, R-N fusion also was associated with a greater progression of valve dysfunction. This was true for both increasing aortic valve gradient (generalized estimating equations [GEE] risk ratio 27.2, 95% CI 1.2 to 619.6, p = 0.0386) and aortic regurgitation (GEE risk ratio 2.4, 95% CI 1.3 to 4.3, p = 0.0029).

CONCLUSION

The morphology of BAV is predictive of clinically important end points. The R-N fusion is associated with a more rapid progression of aortic stenosis and regurgitation and a shorter time to valve intervention.

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.

Clinical update on adults with congenital heart disease

The number of patients with congenital cardiac disease reaching adulthood is increasing steadily. Many adults with such disease face both medical and surgical difficulties. Most clinicians know very little about basic cardiac defects, their natural history, complications after surgery, and adequate management of these patients. We aim to provide an overview of the most frequently encountered cardiac lesions and long-term complications and to outline an up-to-date approach to their management. We present a series of hypothetical cases and discuss their management.

Outcomes of uncomplicated aortic valve stenosis presenting in infants

BACKGROUND

The management of uncomplicated aortic valve stenosis presenting with critical obstruction in infants continues to be associated with significant morbidity and mortality. However, not all infants have critical obstruction, and outcomes spanning the broader spectrum of disease severity are less well defined.

METHODS

In a 12-year period, 55 infants (<3 months of age) were seen with aortic valve stenosis and with anatomy suitable for biventricular repair. Clinical, echocardiographic, angiographic, management, and outcome data were reviewed.

RESULTS

Status at presentation (median age 6 days) included signs of congestive heart failure in 20 patients, cardiovascular collapse in 5 patients, and an asymptomatic heart murmur in 30 patients. The initial echocardiogram showed reduced left ventricular function in 26% of patients, with a mean peak instantaneous gradient of 69 +/- 30 mm Hg in patients with normal function. There were 5 deaths (9%), all in patients with poor ventricular function. The initial intervention was balloon valvotomy in 24 patients and surgical valvotomy in 20 patients, with 11 patients having no intervention to date. The freedom-from-intervention rate was 69% at age 1 week, 58% at 1 month, 36% at 3 months, and 28% at 1 year. Patients without cardiovascular collapse, normal left ventricular function, and gradients <60 mm Hg at presentation (n =1 9) had better survival and longer freedom from intervention than patients with poor ventricular function or gradients >or=60 mm Hg (n = 36, P =.0001).

CONCLUSION

Most infants with aortic valve stenosis receive intervention, although this may be safely delayed in selected patients with lower initial gradients and good left ventricular function.

Survival with congenital heart disease and need for follow up in adult life

OBJECTIVE

To predict the growth in demand for long term follow up of adults with congenital heart disease.

DESIGN

Observed diagnoses of congenital heart disease in infancy and childhood were adjusted for observed infant survival, predicted further survival to age 16 years, underascertainment in older childhood, and predicted need for long term follow up.

SETTING

The resident population of one health region in the UK.

PATIENTS

All confirmed cardiovascular malformations diagnosed in 1985 to 1999 in children born in 1985 to 1994.

RESULTS

1942 cases of congenital heart disease were diagnosed in infancy in a population of 377 310 live births (5.2/1000). 1588 (82%) survived to 1 year and 1514 were predicted to survive to age 16. 605 further diagnoses were made in childhood-678 when adjusted for underascertainment. Thus, 2192 children were predicted to reach age 16, of whom 784 would require long term follow up in adult life. The adult population would comprise 28% complex, 54% significant, and 18% minor congenital heart disease. These figures predict the need for adult follow up of congenital heart disease of over 200 extra cases per 100 000 live births each year or over 1600 extra cases a year every year in the UK.

CONCLUSIONS

The need for follow up of congenital heart disease in adult life is likely to grow linearly, with increasing complexity and increasing need for reinvestigation and reintervention with time. Appropriate provision should be made for adequate manpower, resources, and facilities for care of these patients.

Cardiac surgery for grown-up congenital heart patients: survey of 307 consecutive operations from 1991 to 1994

The cardiac surgery performed from 1991 to 1994 in a unit dedicated specifically for grown-up congenital heart (GUCH) patients was reviewed to determine the frequency of various procedures, incidence of first and reoperations, early mortality, and its determinants. The 295 patients, aged 16 to 77 years (31 +/- 13), had 307 operations. First operations (n = 128, 42%) were most commonly for closure of atrial septal defect (n = 40), aortic valve replacement (n = 31) or repair of aortic coarctation (n = 14). Reoperations were more frequent (n = 179, 58%) and divided among first corrective repair (n = 49), reoperation after corrective repair (n = 115), and further palliation (n = 15). First corrective surgery was mainly for aortic valve disease (n = 17), Fallot (n = 7), and lesions needing a Fontan procedure (n = 5). Reoperations after corrective repair were needed for aortic valve disease (n = 43), right-sided conduit (n = 30), or recoarctation (n = 11). Early mortality was influenced by presence of central cyanosis (9 of 49, 18% in cyanotic patients; 12 of 258, 5% in acyanotic; p <0.001), increased number of previous operations (0 = 4%, 1 = 7%, 2 = 11%, >2 = 13%; p = 0.003), and increasing age of patients. Cyanotic patients had more serious postoperative complications: pleural and pericardial effusions, severe bleeding, renal insufficiency, and sepsis, and their hospital stay was longer compared with acyanotic patients (20 +/- 17 vs 11 +/- 8 days; p <0.001). In GUCH patients, reoperations cause the largest demand on cardiac surgical services. Increased survival of patients with complex cardiovascular malformations brings difficult challenges not only to cardiologists but also to cardiovascular surgeons. There is a need to provide continued highly specialized care. Resources, patients, and funding should be concentrated in a few designated centers.

Independent predictors of immediate results of percutaneous balloon aortic valvotomy in children. Valvuloplasty and Angioplasty of Congenital Anomalies (VACA) Registry Investigators

Smaller patient series have not explored the independent relations between patient selection and technical factors that may impact on acute results of percutaneous balloon aortic valvotomy. To determine such relations, results from the Valvuloplasty and Angioplasty of Congenital Anomalies Registry were examined from 630 balloon aortic valvotomies in 606 patients from 23 institutions. Median age was 6.8 years (range 1 day to 18 years). The procedure could not be performed or completed in 4.1%. The left ventricular to aortic gradient was reduced by a mean +/- SD of 60 +/- 23% (p < 0.0001). Procedure-related mortality was 1.9%. A suboptimal outcome was defined arbitrarily as failure to perform the procedure, a residual gradient > or = 60 mm Hg or LV: aortic pressure ratio > or = 1.6, or major morbidity or mortality, and was noted for 17% of procedures. Independent risk factors from multiple logistic regression analyses included age < 3 months, higher preprocedure gradient, earlier procedure date, the presence of unrepaired aortic coarctation, and the use of undersized balloons. Detailed analysis revealed the optimal balloon: valve diameter ratio to be 0.9 to 1.0, with undersized balloons resulting in significant residual obstruction and oversized balloons resulting in aortic regurgitation complications. Improvements in results over time were related to increasing experience within individual institutions. Thus, percutaneous balloon aortic valvotomy provides adequate relief of obstruction, with minimal complications in most patients.