Ultrasound‐Based Z Score and Pulmonary Valve/Aortic Valve Diameter Ratio Improving the Predictive Value of Fetal Aortic Stenosis

Hypertrophy is considered one of the major mechanisms of the myocardium for adapting to hemodynamic overload. More muscle mass provides more contractile elements for generating the extra work required by the overload. In pressure overload of aortic valve stenosis, concentric left ventricular hypertrophy (LVH) normalizes wall stress, a key determinant of ejection performance.1 Afterload is often expressed as wall stress (pressure×radius/thickness). As the pressure term in the numerator increases, it is offset by an increase in the thickness term of the denominator. In this way, the high systolic pressure required to drive blood through even a very stenotic aortic valve can be consistent with normal afterload and normal ejection fraction. See p 3170 Unfortunately, hypertrophy not only provides benefits but also has many pathological consequences. One of these is myocardial ischemia and the attendant angina reported by patients with aortic stenosis despite normal epicardial coronary arteries. The onset of angina greatly increases the risk of sudden death compared with the risk in asymptomatic patients with aortic valve stenosis.2,3 Angina occurs when myocardial oxygen demand exceeds supply. Demand is proportional to heart rate and wall stress, and the latter can be elevated in cases of aortic stenosis when hypertrophy is inadequate to normalize stress.1 After aortic valve replacement, there is marked regression of hypertrophy that may occur over the next several months to years,4 but angina is relieved immediately. Relief of angina immediately after surgery is probably due to the combination of sudden decreased oxygen demand after removal of pressure overload and increased oxygen supply of improved perfusion. However, there are remaining questions about the physiological mechanisms for reduced myocardial oxygen supply (coronary blood flow) in aortic stenosis and its improvement after relief of pressure overload. Specifically, what is it about critical aortic stenosis that is “critical” …

Recommendations for Evaluation of Prosthetic Valves With Echocardiography and Doppler Ultrasound: A Report From the American Society of Echocardiography's Guidelines and Standards Committee and the Task Force on Prosthetic Valves, Developed in Conjunction With the American College of Cardiology Cardiovascular Imaging Committee, Cardiac Imaging Committee of the American Heart Association, the European Association of Echocardiography, a registered branch of the

1. Talha Niaz, MBBS* 2. Jonathan N. Johnson, MD*,† 3. Frank Cetta, MD*,† 4. Timothy M. Olson, MD*,† 5. Donald J. Hagler, MD*,† 1. *Division of Pediatric Cardiology, Department of Pediatric and Adolescent Medicine, and 2. †Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN * Abbreviations: AHA : : American Heart Association BAV : : bicuspid aortic valve TTE : : transthoracic echocardiography Bicuspid aortic valve is the most common congenital heart defect in children, adolescents, and adults. Primary care providers play an important role in screening, referral, and follow-up of these patients and should be aware of the family screening guidelines, sports participation recommendations, and periodic follow-up requirements for adequate surveillance of the complications that arise from bicuspid aortic valve. After reading this article, readers should be able to: 1. Describe the epidemiology and anatomy of bicuspid aortic valve (BAV). 2. Understand the clinical presentation and diagnosis of BAV in infants, children, and adolescents. 3. Identify the various complications of BAV disease. 4. Discuss the management and follow-up requirements for BAV. 5. Analyze the family screening and sports participation guidelines for patients with BAV. Bicuspid aortic valve (BAV) is the most common congenital heart defect in children, adolescents, and adults. (1) It is a heterogeneous disease that affects both the aortic valve and the aorta. It can lead to many complications, including aortic valve stenosis, regurgitation, or endocarditis. (2)(3) It also can lead to dilation of the aorta, predisposing individuals to a significantly higher risk of aortic aneurysm and dissection. (4) Although most individuals with BAV present with these long-term complications during adulthood, a considerable number of patients may also present during childhood and adolescence with early-onset disease; that may require interventions in up to 12% to 15% of the patients. (5)(6) Therefore, patients with BAV require lifelong follow-up and surveillance. BAV has multiple implications in terms of sports participation and family screening, making it an important subject for primary care providers. This article reviews the anatomy, genetics, presentation, diagnosis, …

There has been a striking evolution in the role of the cardiac catheterization laboratory over the past decades.1 In the 1950s and 1960s, hemodynamic assessment in the cardiac catheterization laboratory was essential for understanding the physiology and pathophysiology of patients with cardiovascular diseases. With the development of surgical interventions to treat patients with valvular and congenital heart disease, it became necessary for the cardiac catheterization laboratory to provide an accurate hemodynamic assessment, laying out a therapeutic road map. Nearly all patients who had open heart surgery underwent a complete hemodynamic catheterization before surgery. In the 1980s and 1990s, the evolution of 2-dimensional echocardiography and Doppler echocardiography provided an alternative noninvasive approach for the assessment of both cardiac anatomy and hemodynamics in patients with structural heart disease.2 By measuring blood flow velocities noninvasively, Doppler echocardiography was able to provide information on volumetric flow, intracardiac pressures, pressure gradients, and valve areas, as well as diastolic filling of the heart. Furthermore, noninvasive studies could be repeated easily, allowing the practitioner to follow the progress of his/her patient's condition longitudinally. At the same time, there was growing emphasis on coronary angiography for defining epicardial coronary disease with the subsequent development of interventional approaches for coronary disease with catheter-based therapies. As the major focus in the catheterization laboratory shifted to the diagnosis and treatment of the patient with acute and chronic coronary artery disease, the hemodynamic assessment of patients with structural heart disease was left to the noninvasive echocardiographic laboratory. As a consequence, many cardiac catheterization laboratories provided neither the training nor the expertise to assess hemodynamics properly. However, the advent of procedures such as balloon valvotomy, percutaneous valve implantation, and septal ablation has revived interest in structural heart disease and provided the invasive cardiologist with an armamentarium to treat patients who previously …

Developmental efforts to achieve percutaneous catheter-based therapies for cardiac valve repair and replacement have advanced rapidly over the past several years. A variety of methods to treat mitral regurgitation (MR) and to replace aortic and pulmonic valves have already been successfully employed in patients. These innovative clinical transcatheter valve therapies were anticipated more than a decade ago by creative experimentalists who helped develop predicate techniques in animal models. For example, in 1992, a catheter-delivered ball-in-cage prosthetic aortic valve was implanted in a canine model by Pavcnik1 and a stent-mounted bioprosthetic valve was placed by Andersen, who used a retrograde transarterial approach in a swine model.2 Clearly, the catheter-based technologies used in clinical studies today in patients with aortic stenosis were derived from the fusion of known successful aortic valve replacement (AVR) surgical devices and adaptive interventional modalities, first studied in experimental animal models. Similarly, approaches for transcatheter treatment of MR have also borrowed heavily from preexisting and accepted surgical techniques, such as the edge-to-edge leaflet coaptation technique and reduction ring mitral annuloplasty.3 Importantly, recognition that the coronary sinus parallels the mitral annulus has spurred unique catheter-based transvenous approaches to treat MR by indirectly reducing mitral annular dimensions.4 Because many of the new percutaneous approaches to valve therapy have been developed by surgeons, a collaboration has emerged between thoughtful surgeons and interventionalists, combining skill sets and experiences to accelerate the developmental pathways of less-invasive transcatheter valve therapies. Growing recognition exists that percutaneous alternatives to surgical therapies are required in some patient subgroups with valvular heart disease. Among patients with either mitral and/or aortic valve disease, an expanding population of elderly patients with significant comorbidities may benefit from traditional surgical methods, but these methods are associated with unacceptable perioperative mortality or prolonged postoperative recoveries. In the EuroHeart Survey …

Acquired Stenosis of All Four Heart Valves in a Boxer Mix Dog

Presentation of Congenital Heart Disease in the Neonate and Young Infant

Case presentation: A 66-year-old man is referred to a cardiologist for the evaluation of a heart murmur. The patient claims to be entirely asymptomatic, although his wife notes that he has decreased his physical activity over the past two years because he is “getting old.” At physical examination, his blood pressure was 120/70 mm Hg; pulse, 80 bpm; respiration, 13 breaths per minute; and temperature, 99.0°F. Cardiovascular examination revealed normal central venous pressure. His carotid upstrokes were reduced in volume and delayed in upstroke. Cardiac examination revealed a forceful sustained apical impulse in its normal position. There was a 3/6 late-peaking systolic ejection murmur heard at the right upper sternal border radiating to the neck. The rest of the physical examination was unremarkable. Echo-Doppler evaluation revealed an ejection fraction of 0.60, a left ventricular free wall thickness of 1.3 cm, and a peak transaortic flow velocity of 4.5 m/s. How should this patient be managed? Should he undergo aortic valve replacement now? Should he undergo longitudinal follow-up to monitor progression of his aortic stenosis? Over the past 40 years, diagnostic techniques, substitute cardiac valves, and valve implantation surgery have undergone continued improvement, reducing the risk of the valve replacement and enhancing its benefits. Thus, the risk-benefit analysis of valve surgery has tilted in favor of increasingly early intervention for valve disease. The following is a summary incorporating this concept into the current strategy for managing patients with aortic stenosis such as the one described above. The patient with severe aortic stenosis who presents with symptoms represents the most straightforward management strategy for the disease. Survival is nearly normal until the classic symptoms of angina, syncope, or dyspnea develop.1 However, only 50% of patients who present with angina survive 5 years, whereas 50% survival is 3 years for patients who …

Fetal aortic valvuloplasty (FV) aims to prevent fetal aortic valve stenosis progressing into hypoplastic left heart syndrome (HLHS), which results in postnatal univentricular (UV) circulation. Despite increasing numbers of FVs performed worldwide, the natural history of the disease in fetal life remains poorly defined. The primary aim of this study was to describe the natural history of fetal aortic stenosis, and a secondary aim was to test previously published criteria designed to identify cases of emerging HLHS with the potential for a biventricular (BV) outcome after FV. From a European multicenter retrospective study of 214 fetuses with aortic stenosis (2005-2012), 107 fetuses in ongoing pregnancies that did not undergo FV were included in this study and their natural history was reported. We examined longitudinal changes in Z-scores of aortic and mitral valve and left ventricular dimensions and documented direction of flow across the foramen ovale and aortic arch, and mitral valve inflow pattern and any gestational changes. Data were used to identify fetuses satisfying the Boston criteria for emerging HLHS and estimate the proportion of these that would have been ideal FV candidates. We applied the threshold score whereby a score of 1 was assigned to fetuses for each Z-score meeting the following criteria: left ventricular length and width > 0; mitral valve diameter > -2; aortic valve diameter > -3.5; and pressure gradient across either the mitral or aortic valve > 20 mmHg. We compared the predicted circulation with known survival and final postnatal circulation (BV, UV or conversion from BV to UV). Among the 107 ongoing pregnancies there were eight spontaneous fetal deaths and 99 livebirths. Five were lost to follow-up, five had comfort care and four had mild aortic stenosis not requiring intervention. There was intention-to-treat in these 85 newborns but five died prior to surgery, before circulation could be determined, and thus 80 underwent postnatal procedures with 44 BV, 29 UV and seven BV-to-UV circulatory outcomes. Of newborns with intention-to-treat, 69/85 (81%) survived ≥ 30 days. Survival at median 6 years was superior in cases with BV circulation (P = 0.041). Those with a postnatal UV circulation showed a trend towards smaller aortic valve diameters at first scan than did the BV cohort (P = 0.076), but aortic valve growth velocities were similar in both cohorts to term. In contrast, the mitral valve diameter was significantly smaller at first scan in those with postnatal UV outcomes (P = 0.004) and its growth velocity (P = 0.008), in common with the left ventricular inlet length (P = 0.004) and width (P = 0.002), were reduced significantly by term in fetuses with UV compared with BV outcome. Fetal data, recorded before 30 completed gestational weeks, from 70 treated neonates were evaluated to identify emerging HLHS. Forty-four had moderate or severe left ventricular depression and 38 of these had retrograde flow in the aortic arch and two had left-to-right flow at atrial level and reversed a-waves in the pulmonary veins. Thus 40 neonates met the criteria for emerging HLHS and BV circulation was documented in 13 (33%). Of these 40 cases, 12 (30%) had a threshold score of 4 or 5, of which five (42%) had BV circulation without fetal intervention. The natural history in our cohort of fetuses with aortic stenosis and known outcomes shows that a substantial proportion of fetuses meeting the criteria for emerging HLHS, with or without favorable selection criteria for FV, had a sustained BV circulation without fetal intervention. This indicates that further work is needed to refine the selection criteria to offer appropriate therapy to fetuses with aortic stenosis. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

2012 ACCF/AATS/SCAI/STS Expert Consensus Document on Transcatheter Aortic Valve Replacement: Developed in collaboration with the American Heart Association, American Society of Echocardiography, European Association for Cardio-Thoracic Surgery, Heart Failure Society of America, Mended Hearts, Society of Cardiovascular Anesthesiologists, Society of Cardiovascular Computed Tomography, and Society for Cardiovascular Magnetic Resonance

Aortic Stenosis Severity: Rhythm Makes a Difference

Coagulation disorders and aortic stenosis: a chicken and egg question?

Body surface area as a predictor of aortic and pulmonary valve diameter

Aortic valve sclerosis is defined by echocardiography as focal areas of increased echogenecity on aortic cusps not inducing stenosis. A maximal aortic velocity value ≥ 2 m/s or ≥ 2.5 m/s is used to differentiate stenosis from sclerosis [1]. The normal aortic valve leaflets consist of a single layer of endothelial cells that envelopes the spongiosa on the aortic side, and the ventricularis on the ventricular side, whereas the central collagenous layer is the fibrosa characterized by a dense collagen [1,2]. Aortic sclerosis probably starts with an endothelial disruption on the aortic side yielding to thickening of the subendothelium and adjacent fibrosa due to accumulation of lipids and inflammatory cells. These aggregates colocalize with areas of microscopic calcification, and some macrophages produce osteopontin, a protein involved in the calcification process. Angiotensin-converting enzyme with local production of angiotensin II has been also identified in human sclerotic aortic valves [1–4]. This stage can be visualized by echocardiography as an irregular leaflet thickening without commissural fusion and stenosis. The prevalence of aortic sclerosis increases with age. In this issue of the journal, Agno et al. [5] report that the prevalence of aortic sclerosis among a population of 1624 patients with hypertension was 5% in patients aged between 45 and 55 years, increasing up to 35% in patients aged 75–85 years. Similarly, the Cardiovascular Health Study (CHS) showed that, among 5621 subjects aged 65 years or older, a prevalence of aortic sclerosis of 29% [6]. When patients with electrocardiographic evidence of left-ventricular hypertrophy (LVH) are considered, the prevalence of aortic sclerosis increases to 40%, as demonstrated by the LIFE study [7]. The attention to this condition has been increased by the observation that aortic sclerosis is not a benign incidental finding on echocardiography, but a marker for increased risk for cardiovascular events, even when baseline cardiovascular factors are taken into account [1]. The CHS demonstrated that, in adult patients older than 65 years, who were followed-up for 5 years, aortic sclerosis is associated with a 40% increase in the risk of myocardial infarction and, in patients without known coronary artery disease at study entry, with a 50% increase in the risk of cardiovascular death [6]. This adverse clinical outcome was also observed in the LIFE study, in which hypertensive patients with such a condition had almost twice the risk for serious cardiovascular events [7]. This adverse outcome is not likely to be related to the reduction of valve area, in that the estimated rate of progression to symptomatic aortic stenosis in adults with a jet velocity below 3.0 m/s is 8% per year or less [8]. Mechanisms other than valve disease per se have to be advanced to understand the factors influencing the prognosis in patients with aortic sclerosis. Epidemiological studies performed during the last decade have demonstrated that the aortic sclerotic process, normally termed ‘degenerative’, shares risk factors and inflammatory similarities with atherosclerosis. Presently, we know that aortic sclerosis is associated with older age, hypertension, elevated low-density lipoprotein cholesterol levels, diabetes, carotid and proximal aortic atherosclerosis and endothelial dysfunction; the association with an inflammatory status has been confirmed in aortic specimens, whereas the association with systemic inflammatory markers remains controversial [1–3,9–13]. By studying only patients with hypertension, Agno et al. [5] showed that aortic sclerosis is independently associated with concentric LVH, worse diastolic function and mitral annular calcification. The assessment of LV mass and geometry, and their changes during treatment, is useful in stratifying cardiovascular risk, and hypertensive patients with concentric hypertrophy have the greatest likelihood of experiencing a cardiovascular event [14,15]. Therefore, the greater prevalence of aortic sclerosis in uncomplicated patients with increased LV mass, which is a well-known and established sign of ‘preclinical disease’, is of particular interest. Agno et al. [5] have confirmed an association previously observed in patients with electrocardiographic LVH participating in the LIFE study [7], and in the elderly normotensive and hypertensive population of the CHS [6], and have further expanded upon these results, evaluating LV geometry. The association with higher LV mass and relative wall thickness, independent of other risk factors, might, at least in part, explain why patients with aortic sclerosis may be at a greater risk of cardiovascular complications. The mechanism of the association remains to be elucidated, although haemodynamic load (peak aortic velocity and gradient) does not appear to play a significant role, and genetic polymorphisms, mainly of the renin–angiotensin–aldosterone system, need to be more accurately evaluated. However, it remains to be demonstrated that normalization of aortic valve sclerosis may be associated with a more favourable outcome and, until this is the case, aortic sclerosis should be considered as a marker, rather than a cause or a consequence, of cardiac hypertrophy and related cardiovascular risk. The association between aortic sclerosis and indices of diastolic dysfunction (increased isovolumic relaxation time and left atrial enlargement) and mitral annular calcification is of interest. In particular, left atrial enlargement is a marker of diastolic dysfunction in the general population and, when used together with Doppler echocardiography, can identify elderly patients with worse diastolic dysfunction who are at an increased risk of developing atrial fibrillation [16,17]. The presence and the severity of mitral annular calcification has been found to be a predictor of morbidity and mortality as demonstrated by the CHS and Framingham Heart Study [18,19]. Left atrial enlargement and mitral annular calcification shares with aortic sclerosis risk factors such as hypertension, coronary artery disease and diabetes mellitus, and the power of an index of cardiovascular risk. The data of Agno et al. [5] suggest that mechanisms capable of inducing changes in myocardial properties, resulting in increased filling pressures, and changes in the structure of mitral annulus, are strictly related to changes in the aortic valve that probably represent a more generalized sclerotic process of the vascular tree [10]. Although the primum movens of the disease process is probably the same, the mechanism activated locally in each structure is different and remains difficult to clarify. The finding that degenerative aortic valve is not a static process, but an active specifically regulated process, suggests that it is potentially modifiable. Retrospective and non-randomized clinical studies have suggested that treatment with statins may be associated with a lower aortic valve calcification progression, as evaluated by electron beam computed tomography, or with a lower progression of aortic stenosis [20–23]. In the LIFE study, the use of statins was similar in patients with and without aortic valve abnormalities, and no significant differences on changes in aortic valve sclerosis and stenosis prevalence were observed between patients randomized to atenolol or losartan-based treatment [24], suggesting that changes in LV mass (and in geometry) during treatment do not parallel improvement or progression of aortic valve sclerosis. Surprisingly, the prevalence of diabetic patients was greater in those patients showing a normalization of aortic valve abnormalities, and the effect of oral antidiabetic agents (or anti-inflammatory drugs) on aortic sclerosis cannot be ruled out. Other prospective studies evaluating the effect of several classes of drugs on aortic valve abnormalities, possibly in younger patients and with a long period of follow-up, are needed to assess the clinical significance of aortic valve sclerosis in hypertensive patients. In conclusion, although the associations and mechanisms of aortic sclerosis remain to be elucidated further, it is now time to bring together the data so far obtained and then create a score in which clinical and echocardiographic alterations, such as aortic sclerosis, contribute to the assessment of the ‘global’ cardiovascular risk. This will have probably the potential for identifying those patients who require more aggressive therapy and/or a closer follow-up.

Recommended Standards for the Performance of Transesophageal Echocardiographic Screening for Structural Heart Intervention: From the American Society of Echocardiography