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Physics-Informed Neural Networks (PINNs) are a new class of machine learning algorithms that are capable of accurately solving complex partial differential equations (PDEs) without training data. By introducing a new methodology for fluid simulation, PINNs provide the opportunity to address challenges that were previously intractable, such as PDE problems that are ill-posed. PINNs can also solve parameterized problems in a parallel manner, which results in favorable scaling of the associated computational cost. The full potential of the application of PINNs to solving fluid dynamics problems is still unknown, as the method is still in early development: many issues remain to be addressed, such as the numerical stiffness of the training dynamics, the shortage of methods for simulating turbulent flows and the uncertainty surrounding what model hyperparameters perform best. In this paper, we investigated the accuracy and efficiency of PINNs for modeling aortic transvalvular blood flow in the laminar and turbulent regimes, using various techniques from the literature to improve the simulation accuracy of PINNs. Almost no work has been published, to date, on solving turbulent flows using PINNs without training data, as this regime has proved difficult. This paper aims to address this gap in the literature, by providing an illustrative example of such an application. The simulation results are discussed, and compared to results from the Finite Volume Method (FVM). It is shown that PINNs can closely match the FVM solution for laminar flow, with normalized maximum velocity and normalized maximum pressure errors as low as 5.74 % and 9.29 % , respectively. The simulation of turbulent flow is shown to be a greater challenge, with normalized maximum velocity and normalized maximum pressure errors only as low as 41.8 % and 113 % , respectively. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Pregnancy can increase gradients across the heart valves and consequently deteriorates maternal and fetoneonatal conditions. Hence, pregnancy during heart valve diseases can be challenging and we need to risk stratify patients before conception. We tried to assess the role of preconception consultation using treadmill stress echocardiography (TSE) testing for identifying pregnancy outcomes in women with mitral valve stenosis (MS) or aortic valve stenosis (AS). METHODS: Pregnant patients with a diagnosis of MS or AS were evaluated from January 2015 to December 2018. First group included patients undergoing the TSE testing and they were permitted to get pregnant if they met pre-defined criteria. Second group comprised women who did not undergo TSE testing. Maternal and fetoneonatal outcomes were also recorded. RESULTS: A total of 29 and 18 patients with MS and AS, respectively, were recruited. Among MS patients, individuals without TSE had more functional deterioration (11.1% vs. 35%) and more fetoneonatal events (FNE) (22.2% vs. 55%) compared with those undergoing TSE. The rates of maternal events and mitral valvuloplasty during pregnancy were significantly higher in patients without TSE compared with those undergoing TSE (p=0.015 and p=0.042, respectively). Among AS patients, maternal and FNE were higher in patients without TSE compared with those undergoing TSE, but those were comparable. CONCLUSION: Pregnant patients with the left-sided valvular stenosis who received preconception TSE testing had better outcomes compared with those who did not undergo preconception consultation. This underscores the utility of stress echocardiography in the risk stratification of pregnancies. [ABSTRACT FROM AUTHOR]

Physics-Informed Neural Networks (PINNs) are a new class of machine learning algorithms that are capable of accurately solving complex partial differential equations (PDEs) without training data. By introducing a new methodology for fluid simulation, PINNs provide the opportunity to address challenges that were previously intractable, such as PDE problems that are ill-posed. PINNs can also solve parameterized problems in a parallel manner, which results in favorable scaling of the associated computational cost. The full potential of the application of PINNs to solving fluid dynamics problems is still unknown, as the method is still in early development: many issues remain to be addressed, such as the numerical stiffness of the training dynamics, the shortage of methods for simulating turbulent flows and the uncertainty surrounding what model hyperparameters perform best. In this paper, we investigated the accuracy and efficiency of PINNs for modeling aortic transvalvular blood flow in the laminar and turbulent regimes, using various techniques from the literature to improve the simulation accuracy of PINNs. Almost no work has been published, to date, on solving turbulent flows using PINNs without training data, as this regime has proved difficult. This paper aims to address this gap in the literature, by providing an illustrative example of such an application. The simulation results are discussed, and compared to results from the Finite Volume Method (FVM). It is shown that PINNs can closely match the FVM solution for laminar flow, with normalized maximum velocity and normalized maximum pressure errors as low as 5.74% and 9.29%, respectively. The simulation of turbulent flow is shown to be a greater challenge, with normalized maximum velocity and normalized maximum pressure errors only as low as 41.8% and 113%, respectively.

Rheumatic heart disease is a serious global health issue that requires early detection and proper secondary prophylaxis. It is critical that governments play an active role in preventive campaigns and ensure access to recommended antibiotics. For symptomatic rheumatic heart disease cases, particularly those with rheumatic mitral stenosis, careful consideration of age and timing of surgical valve replacement is necessary, with a preference for noninvasive interventions when possible. Decision-making should involve a multidisciplinary heart team that assesses patient risks and valve morphology., Competing Interests: The authors have reported that they have no relationships relevant to the contents of this article to disclose., (© 2024 The Authors.)

We present a case of successful balloon pulmonary valvuloplasty (BPV) in a 37-year-old female with severe valvular pulmonary stenosis with peak gradient of 82 mmHg with history of exertional presyncope. The crux of our case was that patient also had associated mild supravalvular pulmonary stenosis which did not preclude a successful BPV outcome. The patient had rare Bombay negative blood group, and the requisite units were not available across all the blood banks in the state to subject the patient for surgical correction. Although the art of BPV is dying among budding young interventionists, this simple procedure is as good as surgical pulmonary valvotomy so far as the immediate and late outcome is concerned and the presence of mild supravalvular pulmonary stenosis does not preclude a successful outcome. Our case is a unique illustration of feasibility of successful balloon pulmonary valvuloplasty in the presence of associated mild supravalvular stenosis. [ABSTRACT FROM AUTHOR]

Background: Frequencies of normal and abnormal heart sounds have previously been reported, but the acoustic analyses of the frequency responses of conventional and amplified stethoscopes for different heart sounds have not yet been reported. Objectives: To compare the acoustic analysis of frequency responses of three stethoscopes (conventional and amplified) for measuring simulated heart sounds. Materials and Methods: This exploratory study used Starkey SLI-ST3, Cardionics E-Scope II (both electronic) and Littmann Classic S.E. II (conventional) stethoscopes, as they share the same basic design with twin ear tubes coupled to ear tips and chest piece options (bell vs. diaphragm modes). Acoustic analyses using the diaphragm were performed in a soundproof booth and frequency response curves at 85 (the largest), 250, 400, 550 and 1050 Hz were compared for three different digitized heart sound simulations: normal, aortic valvular stenosis (AVS) and pulmonic valvular stenosis. Results: Amplified stethoscopes provided the most amplification of normal and abnormal heart sounds across all five frequencies compared with the conventional stethoscope. The Starkey SLI-ST3 stethoscope was better at amplifying normal heartbeats than the Cardionics E-Scope II and Littman Classic S.E. II; however, it came last for amplifying normal heartbeats of ~85 Hz. Cardionics E-Scope II had advantages in amplifying abnormal heartbeats (i.e., aortic valvular stenosis and pulmonic valvular stenosis) over the other two stethoscopes. Conclusion: This study showed that amplified stethoscopes provided better amplification of normal and abnormal heart sounds across the five measured frequencies. Therefore, health professionals should interpret manufacturer claims regarding gain (dB) and frequency (Hz) with caution, and those with hearing loss should carefully investigate the “audio performance” of the stethoscopes. Future research should focus on these effects through coupling with hearing aids.

Cardiac magnetic resonance (CMR) has emerged as the gold standard in assessing ventricular mass, volume, and systolic function. Due to these and other strengths, CMR has increasingly been used to study valvular heart disease (VHD) and resultant cardiac remodeling. By using CMR to assess flow, limitations in echocardiographic assessment of VHD can be overcome, particularly in regurgitant lesions. The following article reviews the current role of CMR imaging in studying disease severity and myocardial remodeling in patients with VHD. [ABSTRACT FROM AUTHOR]

Balloon instability is commonly encountered during balloon pulmonary valvuloplasty (BPV) and may result in an unsuccessful procedure. The NuCLEUS-X™ catheter is a recently developed BPV catheter with a unique barbell shape and an ordered pattern of inflation that stabilizes the balloon to span the valve annulus before expansion of the balloon center. Ten client-owned dogs with severe valvular pulmonic stenosis (PS). Prospective observational study. The BPV procedure was performed by standard technique with use of NuCLEUS-X™ catheters targeting a balloon-to-annulus ratio between 1.2 and 1.5. Balloon stability, safety, and procedural success were assessed. Procedural success was defined as either a reduction in the Doppler transpulmonic PG by at least 50% of the pre-procedural PG or <80 mmHg one month post procedure. Balloon stability centered at the pulmonic valve on the first inflation was achieved in 10/10 cases. The mean PG before BPV was 141 mmHg ±41 mmHg, and the PG after BPV at one month was 83 mmHg ±41 mmHg. Procedural success was achieved in 56% of patients. All dogs survived the BPV, and no major procedural complications were encountered using the NuCLEUS-X™ catheter. The use of the NuCLEUS-X™ catheter is feasible for BPV in dogs with severe PS. The unique balloon shape provided catheter stability on the first inflation in all dogs, which may be beneficial when stabilization of a conventional BPV catheter cannot be achieved. [ABSTRACT FROM AUTHOR]

A six-year-old female goat was presented to the veterinary teaching hospital of the University of the West Indies with a history of progressive hind-limb paresis lasting two weeks. The doe developed a grade 6/6 holosystolic murmur during hospitalisation. Echocardiography revealed vegetative growths attached to cusps of the mitral and aortic valves. Therewas an accelerated aortic flow at 2.9 m/s and aortic insufficiency. The aortic vegetation was prolapsing into the left ventricle during diastole, causing it to contact the septal mitral valve leaflet. A diagnosis of mitral and aortic vegetative endocarditis, with a mitral kissing vegetation and mild aortic stenosis, was reached. The patient was placed on broad-spectrum antimicrobials. A short-term follow-up showed no resolution of clinical signs, and the animal eventually died. Post-mortem examination showed severe vegetative, fibrino-necrotic, aortic and mitral valve lesions. The goat also had a severe fibrino-suppurative mastitis. Histopathology confirmed the lesions to be vegetative endocarditis. [ABSTRACT FROM AUTHOR]

Maternal autoantibodies to Ro/SSA are often linked to congenital heart block and rarely associated with structural defects. We describe the case of a fetus with anti-Ro-mediated second-degree block at 19 weeks, which progressed to a complete block, fibroelastosis, atrioventricular valve insufficiency, and semilunar valve stenosis/insufficiency at 20, 22, 24, and 26 weeks, respectively, although the fetus received transplacental anti-arrhythmic drugs. The 2150-g fetus was vaginally delivered at 35 weeks. An external pacemaker was inserted immediately after birth and replaced with permanent pacemaker at the age of 3 months. The newborn has had a good outcome with well-controlled heart rate. [ABSTRACT FROM AUTHOR]

A six-year-old female goat was presented to the veterinary teaching hospital of the University of the West Indies with a history of progressive hind-limb paresis lasting two weeks. The doe developed a grade 6/6 holosystolic murmur during hospitalisation. Echocardiography revealed vegetative growths attached to cusps of the mitral and aortic valves. There was an accelerated aortic flow at 2.9 m/s and aortic insufficiency. The aortic vegetation was prolapsing into the left ventricle during diastole, causing it to contact the septal mitral valve leaflet. A diagnosis of mitral and aortic vegetative endocarditis, with a mitral kissing vegetation and mild aortic stenosis, was reached. The patient was placed on broad-spectrum antimicrobials. A short-term follow-up showed no resolution of clinical signs, and the animal eventually died. Post-mortem examination showed severe vegetative, fibrino-necrotic, aortic and mitral valve lesions. The goat also had a severe fibrino-suppurative mastitis. Histopathology confirmed the lesions to be vegetative endocarditis.

Valvular heart disease is a common phenomenon in patients undergoing chronic hemodialysis. Abnormalities include valvular and annular thickening and calcification of any of the heart valves, causing regurgitation and/or stenosis. Valvular thickening or sclerosis in patients undergoing chronic dialysis treatment usually affects the aortic and mitral valve. Aortic valve calcification is recorded in up to a half of hemodialyzed patients, occurring from 10 to 20 years earlier than in the general population. Valvular regurgitation occurs mostly in mitral, tricuspid and less commonly in aortic valve.The aim of the article was to determine the incidence of valvular heart disease in asymptomatic patients undergoing chronic dialysis. The analysis involves a total of 50 patients, of whom 35 (70%) are treated by hemodialysis and 15 (30%) by continuous ambulatory peritoneal dialysis. Valvular thickening or sclerosis was diagnosed in 20 (40%) patients. Sclerosis of mitral cusps was diagnosed in 9 (18%) patients and sclerosis of aortic cusps was diagnosed in 11 (22%) patients. Heart valve calcifications were diagnosed in 12 (31%) patients. Mild aortic stenosis was present in 3 (6%) patients. Mitral regurgitation was diagnosed in 38 (76%) patients, aortic regurgitation in 14 (28%), and tricuspid regurgitation in 24 (48%) patients. The evaluation of the valve apparatus for all patients undergoing chronic dialysis program requires echocardiographic examination that is to be performed, considering the high prevalence of valvular heart diseases. [ABSTRACT FROM AUTHOR]

Although ischemic heart disease remains the leading cause of cardiac-related morbidity and mortality in the industrialized countries, a growing number of mainly elderly patients will experience a problem of valvular heart disease (VHD), often requiring surgical intervention at some stage. Doppler-echocardiography is the most popular imaging modality used in the evaluation of this disease entity. It encompasses, however, some non-negligible constraints which may hamper the quality and thus the interpretation of the exam. Cardiac catheterization has been considered for a long time the reference technique in this field, however, this technique is invasive and considered far from optimal. Cardiovascular magnetic resonance imaging (MRI) is already considered an established diagnostic method for studying ventricular dimensions, function and mass. With improvement of MRI soft- and hardware, the assessment of cardiac valve function has also turned out to be fast, accurate and reproducible. This review focuses on the usefulness of MRI in the diagnosis and management of VHD, pointing out its added value in comparison with more conventional diagnostic means. [ABSTRACT FROM AUTHOR]

Surgical treatment of various septal defects has been long established. With the advances in transcatheter therapy dilatation techniques for valvular stenosis and vascular obstruction have become established procedures. Closure of septal defects in the catheterization laboratory has also been introduced; some of these have come into regular use in current practice. In 1967, Porstmann et al reported the use of Ivalon plug to close patent ductus arteriosus (PDA). Since then, several devices have been used including Rashkind PDA ocluder (not being used now), Gianturco coils, detachable coils (for small PDA), CardioSEAL and other umbrella devices and Amplatzer PDA occluder. Closure rates vary from 95-98% in most series, however, some of these devices are very expensive, more so, when compared to the cost of surgical ligation of PDA. Catheter closure of secundum atrial septal defect (ASD) has also been done by various devices like clamshell device, Sideris Buttoned device, ASDOS device, Amplatzer device and cardioSEAL. So far no device has been accepted as ideal for every case, however, Amplatzer device has been used most extensively. Issues such as completeness of endothelialisation, incidence of late arrhythmias, endocarditis remain uncertain. However, in select population of ASD cases with a central secundum defect, device closure is being used increasingly. Device closure of ventricular septal defect remains challenging and controversial and is probably available to a small group of children with defects that are difficult to close surgically and involve higher risk. [ABSTRACT FROM AUTHOR]

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Magnetic resonance techniques can be employed to depict valvular abnormalities but are especially helpful in quantifying regurgitant or stenotic lesions which cannot be quantitatively assessed by other noninvasive techniques. Gradient echo techniques and phase velocity mapping are the most important magnetic resonance pulse sequences employed for these purposes. Valvular regurgitation can be quantitated by measuring the area of signal void on conventional gradient-echo images, by calculating stroke volume differences from k-space segmented gradient echo images, by measuring the proximal convergence zone from velocity encoded images or by comparing stroke volumes of the ventricles from velocity measurements. In contrast to this variety of possibilities in regurgitant lesions, stenotic lesions can only be quantitated by using velocity mapping techniques. Magnetic resonance spectroscopy can be used to assess myocardial metabolism in chronic valvular lesions. However, this tool needs further development and more clinical data before its use can be recommended to assess the necessity and optimal timing of surgical intervention. [ABSTRACT FROM AUTHOR]

Doppler echocardiography, when used alone and in conjunction with two-dimensional echocardiography, provides information pertaining to intracardiac blood flow dynamics. Pulsed Doppler techniques have the ability to localize intracardiac blood flow velocity patterns. This allows for the interrogation of specific cardiac chambers for both normal and abnormal flow. Disorders such as intracardiac shunts, valvular regurgitation, and stenotic lesions can be detected and evaluated with this technique. The location, duration, and timing of flow velocity information can be assessed, allowing diagnoses to be made with this technique that could not be made with imaging alone. Continuous-wave Doppler allows for evaluation of maximal velocity information, which can be used to quantitate intracardiac pressure information such as the gradient across a stenotic valve or the pressure drop across a regurgitant valve. A new twodimensional color flow mapping system provides a noninvasive method for evaluating intracardiac blood flow in ways that previously could only be accomplished through the use of angiographic techniques. This technique has shown promise in allowing evaluation of blood flow dynamics never before available with noninvasive techniques. When combined with two-dimensional echocardiography, Doppler echocardiographic techniques provide information which allow for a more complete and accurate noninvasive evaluation of cardiovascular disorders. [ABSTRACT FROM PUBLISHER]

Background: Acute rheumatic fever (ARF) and its post-inflammatory sequel chronic rheumatic heart disease (RHD) are endemic in the Indian setting. Despite the updated Jones criteria, many cases of ARF remain undiagnosed or are missed., Aims: This study aims to analyze pathological profiles of such cases and their importance in context of clinical presentation and Jones criteria., Materials and Methods: A 22-year retrospective observational study of ARF was conducted in the Department of Pathology in a tertiary care institute. The cases were categorized as 1. Those fulfilling and 2. those partially or not fulfilling the Jones Criteria. Based on the autopsy findings, the lesions were classified as categorized mitral stenosis and/or regurgitation (MS ± MR) and pure mitral regurgitation (MR)., Statistical Analysis: Nil., Results: In 22 years, among 697 cases of autopsied cases of RHD, there were 59 cases (8.5%) of ARF. Among them, seven cases fulfilled the Jones criteria; five of them were clinically diagnosed. The remaining 52 cases (88.1%, 34 with MS ± MR and 18 with MR) did not fulfill or partially fulfilled the Jones criteria and were not diagnosed. A total of 18 patients (30.5%) had the first attack of ARF, whereas recurrences were noted in the remaining patients (69.5%)., Conclusions: The study indicates that the typical manifestations of ARF under Jones criteria may not be present, especially in cases with recurrence. Hence, a presumptive or possible diagnosis of ARF can be made with presence of minor criteria or strong clinical suspicion in such cases.