Aortic Valve Regurgitation: A Comprehensive Review

Short-Term Outcomes of Transcatheter Aortic Valve Replacement in Low-Risk Patients With Pure Severe Aortic Regurgitation

Transcatheter aortic valve replacement (TAVR) has emerged as an alternative treatment for patients with pure severe aortic regurgitation (PSAR) who are contraindicated for surgery or have a high surgical risk. However, the therapeutic efficacy and safety of TAVR in low Society of Thoracic Surgeons (STS) score risk patients remain to be clarified. This study aimed to explore the feasibility of TAVR treatment in different STS-risk patients and to compare the adverse events between the groups. In this study, patients with PSAR who underwent TAVR at Zhongshan Hospital, Fudan University, China, during the inclusion period were included and categorized into 3 groups based on STS scores. The baseline data, imaging results, and follow-up data of the patients were documented. Therefore, of 75 TAVR patients, 38 (50.7%) were categorized as low risk (STS <4), and 37 (49.3%) patients were categorized as intermediate and high risk (STS ≥4). Compared with patients at intermediate and high risk, those in the low-risk group were younger, had a lower body mass index, had a lower prevalence of hypertension, chronic obstructive pulmonary disease, and previous percutaneous coronary intervention, and had better cardiac function (p all <0.05). In the hospital and at the 1-month follow-up, the degree of aortic regurgitation and cardiac function were significantly improved. No significant difference was found between the 2 groups in the hospital or during the 30-day follow-up. In conclusion, TAVR for PSAR in low-STS-risk patients is safe and efficient during 30 days of follow-up compared with intermediate- and high-STS-risk groups. TAVR for PSAR should not be limited to inoperable or STS-defined high-risk patients. Long-term follow-up is needed for further investigation.

Development and validation of a risk prediction model for valve regurgitation in Behçet's disease

BACKGROUND

In Behçet's disease (BD), mild-to-severe valvular regurgitation (VR) poses a serious complication that contributes significantly to heart failure and eventually death. The accurate prediction of VR is crucial in the early stages of BD subjects for improved prognosis. Accordingly, this study aimed to develop a nomogram that can detect VR early in the course of BD.

METHODS

One hundred seventy-two patients diagnosed with Behçet's disease (BD) were conducted to assess cardiac valve regurgitation as the primary outcome. The severity of regurgitation was classified as mild, moderate, or severe. The parameters related to the diagnostic criteria were used to develop model 1. The combination of stepAIC, best subset, and random forest approaches was employed to identify the independent predictors of VR and thus establish model 2 and create a nomogram for predicting the probability of VR in BD. Receiver operating characteristics (ROC) and decision curve analysis (DCA) were used to evaluate the model performance.

RESULTS

Thirty-four patients experienced mild-to-severe VR events. Model 2 was established using five variables, including arterial involvement, sex, age at hospitalization, mean arterial pressure, and skin lesions. In comparison with model 1 (0.635, 95% CI: 0.512-0.757), the ROC of model 2 (0.879, 95% CI: 0.793-0.966) was improved significantly. DCA suggested that model 2 was more feasible and clinically applicable than model 1.

CONCLUSION

A predictive model and a nomogram for predicting the VR of patients with Behçet's disease were developed. The good performance of this model can help us identify potential high-risk groups for heart failure. Key Points • In this study, the predictors of VR in BD were evaluated, and a risk prediction model was developed for the early prediction of the occurrence of VR in patients with BD. • The VR prediction model included the following indexes: arterial involvement, sex, age at hospitalization, mean arterial pressure, and skin lesions. • The risk model that we developed was better and more optimized than the models built with diagnostic criteria parameters, and visualizing and personalizing the model, a nomogram, provided clinicians with an easy and intuitive tool for practical prediction.

Mixed aortic valve disease: association with paravalvular leak and reduced survival after transcatheter aortic valve replacement

AIMS

Transcatheter aortic valve replacement (TAVR) revolutionized the therapy of severe aortic stenosis (AS) with rising numbers. Mixed aortic valve disease (MAVD) treated by TAVR is gaining more interest, as those patients represent a more complex cohort as compared with isolated AS. However, concerning long-term outcome for this cohort only, limited data are available. The aim of the study is to assess the prevalence of MAVD in TAVR patients, investigate its association with paravalvular regurgitation (PVR), and analyse its impact on long-term mortality after TAVR.

METHODS AND RESULTS

We conducted a registry-based cohort study using the Vienna TAVR registry, enrolling patients who underwent TAVR at Medical University of Vienna between January 2007 and May 2020 with available transthoracic echocardiography before and after TAVR (n = 880). Data analysis included PVR incidence and long-term survival outcomes. A total of 647 (73.52%) out of 880 patients had ≥ mild aortic regurgitation next to severe AS. MAVD was associated with PVR compared with isolated AS with an odds ratio of 2.06, 95% confidence interval (CI): 1.51-2.81 (P = <0.001). More than mild PVR after TAVR (n = 168 out of 880: 19.09%) was related to higher mortality compared with the absence of PVR with a hazard ratio (HR) of 1.33, 95% CI: 1.05- 1.67 (P = 0.016). MAVD patients developing ≥ mild PVR after TAVR were also associated with higher mortality compared with the absence of PVR with an HR of 1.30 and 95% CI: 1.04-1.62 (P = 0.022).

CONCLUSION

MAVD is prevalent among TAVR patients and presents unique challenges, with increased PVR risk and worse outcomes compared with isolated AS. Long-term survival for MAVD patients, not limited to those developing PVR post-TAVR, is compromised. Earlier intervention before the occurrence of structural myocardial damage or surgical valve replacement might be a potential workaround to improve outcomes.

Aortic Regurgitation: Review of Current Management

ABSTRACT

Aortic regurgitation (AR) is a valvular disease characterized by retrograde blood flow from the aorta to the left ventricle. Various etiologies result in either an acute or chronic clinical presentation of AR and affect the severity of disease progression. Acute AR is a medical emergency caused by sudden increases in left ventricular volume. Immediate surgical intervention, vasoactive agents, and antibiotics are crucial for management. Chronic AR progresses gradually, leading to heart failure symptoms due to left ventricular remodeling. Diagnoses of both acute and chronic AR rely on electrocardiography, chest radiographs, and echocardiography. Cardiac magnetic resonance imaging may be incorporated in chronic AR diagnosis. Medical management of chronic AR aims to control hypertension and delay left ventricular dysfunction. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and potentially calcium-channel blockers are recommended for chronic AR. β-Blockers are cautioned against because of their potential negative effects. This article emphasizes the importance of early diagnosis and prompt surgical intervention in AR. This review provides a comprehensive overview of the pathophysiology and clinical manifestations of acute and chronic AR and a medication regimen for treating chronic AR in the adult population.

Prognostic Value of Left Ventricular Global Longitudinal Strain for Major Adverse Cardiovascular Events in Patients with Aortic Valve Disease: A Meta-Analysis

INTRODUCTION

Valvular heart disease is one of the most common heart diseases. It is characterized by abnormal function or structure of the heart valves. There may be no clinical symptoms in the early stages. Clinical symptoms of arrhythmia, heart failure, or thromboembolic events may occur in the late stages of the disease, such as palpitation after activities, breathing difficulties, fatigue, and so on. Aortic valve disease is a major part of valvular heart disease. The main treatment for aortic valve disease is valve replacement or repair surgery, but it is extremely risky. Therefore, a rigorous prognostic assessment is extremely important for patients with aortic valve disease. The global longitudinal strain is an index that describes the deformation capacity of myocardium. There is evidence that it provides a test for systolic dysfunction other than LVEF (left ventricular ejection fraction) and provides additional prognostic information.

METHOD

Search literature published between 2010 and 2023 on relevant platforms and contain the following keywords: "Aortic valve disease," "Aortic stenosis," "Aortic regurgitation," and "longitudinal strain" or "strain." The data is then extracted and collated for analysis.

RESULTS

A total of 15 articles were included. The total population involved in this study was 3,678 individuals. The absolute value of LVGLS was higher in the no-MACE group than in the MACE group in patients with aortic stenosis (Z = 8.10, p < 0.00001), and impaired LVGLS was a risk factor for MACE in patients with aortic stenosis (HR = 1.14, p < 0.00001, 95% CI: 1.08-1.20). There was also a correlation between impaired LVGLS and aortic valve surgery in patients with aortic valve disease (HR = 1.16, p < 0.0001, 95% CI: 1.08-1.25) or patients with aortic valve regurgitation (HR = 1.21, p = 0.0004, 95% CI: 1.09-1.34). We also found that impaired LVGLS had no significant association between LVGLS and mortality during the period of follow-up in patients with aortic valve stenosis (HR = 1.08, 95% CI: 0.94-1.25, p = 0.28), but it was associated with mortality in studies of prospective analyses (HR = 1.34, 95% CI: 1.02-1.75, p = 0.04).

CONCLUSIONS

Impaired LVGLS correlates with major adverse cardiovascular events in patients with aortic valve disease, and it has predictive value for the prognosis of patients with aortic valve disease.

Transcatheter aortic valve implantation versus surgical aortic valve replacement for pure aortic regurgitation: a systematic review and meta-analysis of 33,484 patients

INTRODUCTION

The published studies comparing transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) in pure aortic regurgitation (AR) are conflicting. We conducted this systematic review and meta-analysis to compare TAVI with SAVR in pure AR.

METHODS

We searched PubMed, Embase, Web of Science (WOS), Scopus, and the Cochrane Library Central Register of Controlled Trials (CENTRAL) from inception until 23 June 2023. Review Manager was used for statistical analysis. The risk ratio (RR) with a 95% confidence interval (CI) was used to compare dichotomous outcomes. Continuous outcomes were compared using the mean difference (MD) and 95% CI. The inconsistency test (I2) assessed the heterogeneity. We used the Newcastle-Ottawa scale to assess the quality of included studies. We evaluated the strength of evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) scale.

RESULTS

We included six studies with 5633 patients in the TAVI group and 27,851 in SAVR. In-hospital mortality was comparable between TAVI and SAVR (RR = 0.89, 95% CI [0.56, 1.42], P = 0.63) (I2 = 86%, P < 0.001). TAVI was favored over SAVR regarding in-hospital stroke (RR = 0.50; 95% CI [0.39, 0.66], P < 0.001) (I2 = 11%, P = 0.34), in-hospital acute kidney injury (RR = 0.56; 95% CI: [0.41, 0.76], P < 0.001) (I2 = 91%, P < 0.001), major bleeding (RR = 0.23; 95% CI: [0.17, 0.32], P < 0.001) (I2 = 78%, P < 0.001), and shorter hospital say (MD = - 4.76 days; 95% CI: [- 5.27, - 4.25], P < 0.001) (I2 = 88%, P < 0.001). In contrast, TAVI was associated with a higher rate of pacemaker implantation (RR = 1.68; 95% CI: [1.50, 1.88], P < 0.001) (I2 = 0% P = 0.83).

CONCLUSION

TAVI reduces in-hospital stroke and is associated with better safety outcomes than SAVR in patients with pure AR.

Complete sternal cleft individualized repair using a 3D-printed polyether ether ketone model: a case report

Background

Bicuspid aortic valve (BAV) is a common anatomical variation that the aortic valve possesses two functional cusps. Sternal cleft is a rare congenital malformation which is caused by failed fusion of sternal bones. Early surgical repair is advised; otherwise, alternative surgical techniques should be performed. Due to their biocompatibility and elasticity, 3D-printed polyether ether ketone (PEEK) implants can be used. Complete sternal cleft coexistence with BAV is infrequent.

Case summary

A 49-year-old man with a 6-month history of paroxysmal shortness of breath and exertional chest tightness presented to our hospital. The man was diagnosed with BAV with severe aortic valve regurgitation and a complete sternal cleft. He underwent aortic valve replacement surgery using the bovine pericardial aortic valve. Concurrently, a 3D-printed PEEK implant surgery was performed to address the sternal cleft. The patient's postoperative recovery was uneventful.

Discussion

In this case, 3D-printed PEEK implants were used for high biocompatibility and elastic modulus. However, because PEEK material inherently lacks biological activity, enhancing this aspect remains a focal point of clinical research.

Surgical outcomes of aortic valve repair for specific aortic valve cusp characteristics; retraction, calcification, and fenestration

OBJECTIVES

We investigated the predictive value of aortic valve cusp retraction, calcification, and fenestration for aortic valvuloplasty feasibility.

METHODS

Multicenter data were collected for 2082 patients who underwent surgical aortic valvuloplasty or aortic valve replacement. The study population had retraction, calcification, or fenestration in at least one aortic valve cusp. Controls had normal or prolapsed cusps.

RESULTS

All cusp characteristics demonstrated significantly increased odds ratios [ORs] for switch to valve replacement. This effect was strongest for cusp retraction, followed by calcification and fenestration (OR, 25.14; P ≤ .001; OR, 13.50, P ≤ .001; OR, 12.32, P ≤ .001). Calcification and retraction displayed increased odds for developing grade 4 aortic regurgitation compared with grade 0 or 1 combined on average over time (OR, 6.67; P ≤ .001; OR, 4.13; P = .038). Patients with cusp retraction showed increased risk for reintervention at 1- and 2-year follow-up after aortic valvuloplasty (hazard ratio, 5.66; P ≤ .001; hazard ratio, 3.22, P = .007). Cusp fenestration was the only group showing neither an increased risk of postoperative severe aortic regurgitation (P = .57) or early reintervention (P = .88) compared with the control group.

CONCLUSIONS

Aortic valve cusp retraction, calcification, and fenestration were all related to increased rates of switch to valve replacement. Calcification and retraction were associated with recurrence of severe aortic regurgitation. Retraction was related to early reintervention. Fenestration was neither associated with recurrence of severe aortic regurgitation or reintervention. This indicates that surgeons are well able to distinguish aortic valve repair candidates in patients with cusp fenestration.

Surgical treatment of Behcet's disease with severe aortic regurgitation

Behcet's disease (BD) is a multisystem inflammatory disease that is characterized by oral aphthosis, genital aphthosis, ocular lesions, and cutaneous lesions. Although BD rarely affects the cardiovascular system, its symptoms can be shown as aortic regurgitation (AR), which requires surgical intervention. Due to the special pathogenesis of BD, a low preoperative diagnosis rate and a high incidence of serious complications, such as perivalvular leakage, valve detachment, and pseudoaneurysm after prosthetic valve replacement, surgical treatment of BD with severe AR has a poor prognosis. In recent years, new surgical strategies have been developed to improve treatment efficacy for this disease. This article reviews and summarizes the evolution of surgical techniques for BD with AR and aims to provide a reference for optimizing surgical strategies, improving perioperative management, and assisting prognosis in patients suffering from BD with severe AR.

Cardiovascular computed tomography for the detection of quadricuspid aortic valve: A case report

Aortic regurgitation (AR) represents a significant cause of morbidity and mortality. Due to its low cost and widespread availability, echocardiography remains the frontline for aortic valve (AV) assessment. However, poor sonographic windows may limit the assessment of valve morphology with this technique. Cardiovascular computed tomography (CCT) is increasingly utilized prior to structural AV interventions. Due to its excellent spatial resolution, CCT provides exceptional characterization of aortic leaflets. Accordingly, we present a case of a quadricuspid valve diagnosed by CCT. Here, CCT led to a new diagnosis of quadricuspid valve, highlighting the potential for CCT for the characterization of aortic leaflet morphology. CCT may be particularly useful in patients with contraindications to transesophageal echocardiography or those undergoing structural or robotic interventions.

Evolving technology: the TRIFLO tri-leaflet mechanical valve without oral anticoagulation: a potential major innovation in valve surgery

The aortic valve is the most frequently diseased valve and aortic stenosis (AS) is the most prevalent valvular heart disease in developed countries. The diseased native aortic valve can be replaced by either a biological or mechanical valve prosthesis. The main concerns relate to durability, the need for oral anticoagulants and the incidence of complications related to this medication. Experimental, computational and biomolecular blood flow studies have demonstrated that the systolic forward flow but also the reverse flow phase at the end of the systole and leakage during the diastolic phase is mainly responsible for platelet activation and thrombosis. Better design of mechanical prosthetic heart valves must ensure smooth closing during flow deceleration and must eliminate high-shear hinge flow during diastole to prevent life-threatening thrombosis. A novel tri-leaflet valve should combine the favorable hemodynamics and the durability of existing mechanical heart valves and eliminate the less favorable characteristics, including the extremely rapid closing. In this paper, we discuss some issues of current mechanical heart valve prostheses and present a new valve design with the potential for significant innovation in the field. The TRIFLO Heart Valve, is a rigid, three-leaflet central flow heart valve prosthesis consisting of an alloyed titanium housing, and three rigid polymer (PEEK) cusps. This valve has a physiological operating mode. During the forward flow phase, the intraventricular pressure opens the leaflets so that blood can freely flow through with little obstruction, and with the deceleration of the blood flow, the leaflets close early and smoothly, minimizing blood flow regurgitation, blood cell damage, and activation of the coagulation cascade. Pre-clinical studies have shown pretty favorable results and a first-in-man study should start very soon.

Identification of hub genes and key signaling pathways by weighted gene co-expression network analysis for human aortic stenosis and insufficiency

Background

Human aortic valve stenosis (AS) and insufficiency (AI) are common diseases in aging population. Identifying the molecular regulatory networks of AS and AI is expected to offer novel perspectives for AS and AI treatment.

Methods

Highly correlated modules with the progression of AS and AI were identified by weighted genes co-expression network analysis (WGCNA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed by the clusterProfiler program package. Differentially expressed genes (DEGs) were identified by the DESeqDataSetFromMatrix function of the DESeq2 program package. The protein-protein interaction (PPI) network analyses were implemented using the STRING online tool and visualized with Cytoscape software. The DEGs in AS and AI groups were overlapped with the top 30 genes with highest connectivity to screen out ten hub genes. The ten hub genes were verified by analyzing the data in high throughput RNA-sequencing dataset and real-time PCR assay using AS and AI aortic valve samples.

Results

By WGCNA algorithm, 302 highly correlated genes with the degree of AS, degree of AI, and heart failure were identified from highly correlated modules. GO analyses showed that highly correlated genes had close relationship with collagen fibril organization, extracellular matrix organization and extracellular structure organization. KEGG analyses also manifested that protein digestion and absorption, and glutathione metabolism were probably involved in AS and AI pathological courses. Moreover, DEGs were picked out for 302 highly correlated genes in AS and AI groups relative to the normal control group. The PPI network analyses indicated the connectivity among these highly correlated genes. Finally, ten hub genes (CD74, COL1A1, TXNRD1, CCND1, COL5A1, SERPINH1, BCL6, ITGA10, FOS, and JUNB) in AS and AI were found out and verified.

Conclusion

Our study may provide the underlying molecular targets for the mechanism research, diagnosis, and treatment of AS and AI in the future.

We Found a Gem in Your Heart: Valvular Heart Disease and Infective Endocarditis Discovered

Valvular heart disease (VHD) occurs when there is a functional impairment in the valvular apparatus that either obstructs or regurgitates the backflow of blood. When a microorganism resides in those valves, it injures the leaflets and causes complications such as thromboembolic events. Infective endocarditis (IE), usually caused by the Staphylococci and Streptococcus group, is a disease that occurs on the heart valves. Antibiotic resistance is common; thus, culture and sensitivity testing should be done for a more targeted treatment approach. We herein present a rare case of Gemella morbillorum (G. morbillorum) vegetations found in a patient's heart that initially presented with cerebrovascular disease symptoms and underwent heart surgery in the end.

Aortic Regurgitation and Heart Failure: Advances in Diagnosis, Management, and Interventions

This review discusses the contemporary clinical evaluation and management of patients with comorbid aortic regurgitation (AR) and heart failure (HF) (AR-HF). Importantly, as clinical HF exists along the spectrum of AR severity, the present review also details novel strategies to detect early signs of HF before the clinical syndrome ensues. Indeed, there may be a vulnerable cohort of AR patients who benefit from early detection and management of HF. Additionally, while the mainstay of operative management for AR has historically been surgical aortic valve replacement, this review discusses alternate procedures that may be beneficial in high-risk cohorts.

Doppler flow morphology characteristics of epiaortic arteries in aortic valve pathologies: a retrospective study on a cohort of patients with ischemic stroke

BACKGROUND AND AIMS

Neurovascular ultrasound (nvUS) of the epiaortic arteries is an integral part of the etiologic workup in patients with ischemic stroke. Aortic valve disease shares similar vascular risk profiles and therefore not only presents a common comorbidity, but also an etiologic entity. The aim of this study is to investigate the predictive value of specific Doppler curve flow characteristics in epiaortic arteries and the presence of aortic valve disease.

METHODS

Retrospective, single-center analysis of ischemic stroke patients, both receiving full nvUS of the extracranial common- (CCA), internal- (ICA) and external carotid artery (ECA) and echocardiography (TTE/TEE) during their inpatient stay. A rater blinded for the TTE/TEE results investigated Doppler flow curves for the following characteristics: 'pulsus tardus et parvus' for aortic valve stenosis (AS) and 'bisferious pulse', 'diastolic reversal', 'zero diastole' and 'no dicrotic notch' for aortic valve regurgitation (AR). Predictive value of these Doppler flow characteristics was investigated using multivariate logistic regression models.

RESULTS

Of 1320 patients with complete examination of Doppler flow curves and TTE/TEE, 75 (5.7%) showed an AS and 482 (36.5%) showed an AR. Sixty-one (4.6%) patients at least showed a moderate-to-severe AS and 100 (7.6%) at least showed a moderate-to-severe AR. After adjustment for age, coronary artery disease, arterial hypertension, diabetes mellitus, smoking, peripheral arterial disease, renal failure and atrial fibrillation, the following flow pattern predicted aortic valve disease: 'pulsus tardus et parvus' in the CCA and ICA was highly predictive for a moderate-to-severe AS (OR 1158.5, 95% CI 364.2-3684.8, p < 0.001). 'No dicrotic notch' (OR 102.1, 95% CI 12.4-839.4, p < 0.001), a 'bisferious pulse' (OR 10.8, 95% CI 3.2-33.9, p < 0.001) and a 'diastolic reversal' (OR 15.4, 95% CI 3.2-74.6, p < 0.001) in the CCA and ICA predicted a moderate-to-severe AR. The inclusion of Doppler flow characteristics of the ECA did not increase predictive value.

CONCLUSIONS

Well defined, qualitative Doppler flow characteristics detectable in the CCA and ICA are highly predictive for aortic valve disease. The consideration of these flow characteristics can be useful to streamline diagnostic and therapeutic measures, especially in the outpatient setting.

The Global Burden of Valvular Heart Disease: From Clinical Epidemiology to Management

Valvular heart disease is a leading cause of cardiovascular morbidity and mortality and a major contributor of symptoms and functional disability. Knowledge of valvular heart disease epidemiology and a deep comprehension of the geographical and temporal trends are crucial for clinical advances and the formulation of effective health policy for primary and secondary prevention. This review mainly focuses on the epidemiology of primary (organic, related to the valve itself) valvular disease and its management, especially emphasizing the importance of heart valve centers in ensuring the best care of patients through a multidisciplinary team.

Valve Repair in Aortic Insufficiency: A State-of-the-art Review

Aortic valve insufficiency (AI) describes the pathology of blood leaking through the aortic valve to the left ventricle during diastole and is classified as mild, moderate or severe according to the volume of regurgitating blood. Intervention is required in severe AI when the patient is symptomatic or when the left ventricular function is impaired. Aortic valve replacement has been considered the gold standard for decades for these patients, but several repair techniques have recently emerged that offer exceptional stability and long-term outcomes. The appropriate method of repair is selected based on the mechanism of AI and each patient's anatomic variations. This review aims to describe different pathologies of AI based on its anatomy, along with the different surgical techniques of aortic repair and their reported results.

Aortic valve neocuspidization using autologous versus bovine pericardium: Ozaki versus Batista

BACKGROUND

The average living age of the population is constantly increasing and so is the incidence and prevalence of aortic valve disease. Surgical aortic valve replacement (SAVR) is the current gold standard treatment. Nevertheless, the use of prosthetic valves in SAVR is associated with issues that impact patients' quality of life. Aortic valve neocuspidization (AV Neo) offers a means to solve this dilemma by minimizing foreign valve tissue. AV Neo can either be performed using glutaraldehyde-treated autologous pericardium (Ozaki procedure) or bovine pericardium (Batista procedure).

AIMS

This commentary aims to discuss the recent study by Chan and colleagues which highlighted the surgical approach, clinical outcomes, and limitations of the Ozaki procedure, and compare this to the Batista procedure.

METHODS

A comprehensive literature search was performed using multiple electronic databases including PubMed, Ovid, Embase, and Scopus to collate the relevant research evidence.

RESULTS

Although the Ozaki procedure can achieve favorable results whilst mainly avoiding the need for life-long oral anticoagulation with mechanical valves, it still has several limitations that may hinder results. AV Neo using glutaraldehyde-treated bovine pericardium, developed by pioneer cardiac surgeon Dr. Randas J. Vilela Batista, yields superior clinical outcomes to Ozaki's, including excellent survival, lower complications, and minimal need for reoperation as well as shorter operative times.

CONCLUSION

AV Neo offers a means to perform SAVR whilst escaping the prosthetic valve issues. However, the Batista procedure has shown beyond doubt that it can be considered the superior approach for AV Neo over the Ozaki procedure.

Mini-sternotomy versus full sternotomy for isolated aortic valve replacement: A single-center experience

BACKGROUND

Minimally invasive approaches to isolated aortic valve replacement (AVR) are well-described and widely utilized. While there are numerous proposed benefits, there is limited literature describing significant morbidity or mortality benefits for minimally invasive isolated AVR resulting in hesitancy in its universal adoption. In this retrospective study, we compare the 5-year outcomes of patients undergoing isolated AVR via full sternotomy (FS) or mini-sternotomy (MS).

METHODS

756 patients underwent isolated AVR between 2014 and 2019. Propensity matching resulted in 142 matched pairs that received either FS or MS. The primary outcome was mortality during the follow-up period. Secondary outcomes included intraoperative variables and postoperative morbidity.

RESULTS

Intraoperative variables including total operative, cardiopulmonary bypass, and aortic cross-clamp times did not differ significantly between groups. Postoperative mortality was similar between the matched groups with nonsignificant differences at 30 days (2.12% vs. 1.4%, p = .657), 1 year (4.9% vs. 2.1%, p = .0.223), and 5 years (7.5% vs. 3.5%, p = .174). Rates of postoperative morbidity were comparable between groups with no significant differences.

CONCLUSION

This study examined the long-term outcomes of propensity-matched patients undergoing isolated AVR via FS or MS and identified no significant differences in outcomes over a 5-year follow-up period. The decision for surgical approach is multifactorial and should be decided on a case-by-case basis taking into consideration patient anatomy, surgeon experience, and comfort, as well as patient preference.

A European update on transcatheter aortic valve implantation (TAVI) in the COVID era

Minimally invasive approaches for aortic valve replacement are now at the forefront of pathological aortic valve treatment. New trials show comparability of these devices to existing therapies, not only in high-risk surgical cohorts but also in low-risk and intermediate-risk cohorts. This review provides vital clinical and anatomical background to aortic valvular disease treatment guidelines, while also providing an update on transcatheter aortic valve implantation (TAVI) devices in Europe, their interventional trials and associated complications.

Revealing Unforeseen Diagnostic Image Features With Deep Learning by Detecting Cardiovascular Diseases From Apical 4-Chamber Ultrasounds

Background

With the increase of highly portable, wireless, and low‐cost ultrasound devices and automatic ultrasound acquisition techniques, an automated interpretation method requiring only a limited set of views as input could make preliminary cardiovascular disease diagnoses more accessible. In this study, we developed a deep learning method for automated detection of impaired left ventricular (LV) function and aortic valve (AV) regurgitation from apical 4‐chamber ultrasound cineloops and investigated which anatomical structures or temporal frames provided the most relevant information for the deep learning model to enable disease classification.

Methods and Results

Apical 4‐chamber ultrasounds were extracted from 3554 echocardiograms of patients with impaired LV function (n=928), AV regurgitation (n=738), or no significant abnormalities (n=1888). Two convolutional neural networks were trained separately to classify the respective disease cases against normal cases. The overall classification accuracy of the impaired LV function detection model was 86%, and that of the AV regurgitation detection model was 83%. Feature importance analyses demonstrated that the LV myocardium and mitral valve were important for detecting impaired LV function, whereas the tip of the mitral valve anterior leaflet, during opening, was considered important for detecting AV regurgitation.

Conclusions

The proposed method demonstrated the feasibility of a 3‐dimensional convolutional neural network approach in detection of impaired LV function and AV regurgitation using apical 4‐chamber ultrasound cineloops. The current study shows that deep learning methods can exploit large training data to detect diseases in a different way than conventionally agreed on methods, and potentially reveal unforeseen diagnostic image features.

Left-Sided Degenerative Valvular Heart Disease in Type 1 and Type 2 Diabetes

BACKGROUND

The role of diabetes in the development of valvular heart disease, and, in particular, the relation with risk factor control, has not been extensively studied.

METHODS

We included 715 143 patients with diabetes registered in the Swedish National Diabetes Register and compared them with 2 732 333 matched controls randomly selected from the general population. First, trends were analyzed with incidence rates and Cox regression, which was also used to assess diabetes as a risk factor compared with controls, and, second, separately in patients with diabetes according to the presence of 5 risk factors.

RESULTS

The incidence of valvular outcomes is increasing among patients with diabetes and the general population. In type 2 diabetes, systolic blood pressure, body mass index, and renal function were associated with valvular lesions. Hazard ratios for patients with type 2 diabetes who had nearly all risk factors within target ranges, compared with controls, were as follows: aortic stenosis 1.34 (95% CI, 1.31-1.38), aortic regurgitation 0.67 (95% CI, 0.64-0.70), mitral stenosis 1.95 (95% CI, 1.76-2.20), and mitral regurgitation 0.82 (95% CI, 0.79-0.85). Hazard ratios for patients with type 1 diabetes and nearly optimal risk factor control were as follows: aortic stenosis 2.01 (95% CI, 1.58-2.56), aortic regurgitation 0.63 (95% CI, 0.43-0.94), and mitral stenosis 3.47 (95% CI, 1.37-8.84). Excess risk in patients with type 2 diabetes for stenotic lesions showed hazard ratios for aortic stenosis 1.62 (95% CI, 1.59-1.65), mitral stenosis 2.28 (95% CI, 2.08-2.50), and excess risk in patients with type 1 diabetes showed hazard ratios of 2.59 (95% CI, 2.21-3.05) and 11.43 (95% CI, 6.18-21.15), respectively. Risk for aortic and mitral regurgitation was lower in type 2 diabetes: 0.81 (95% CI, 0.78-0.84) and 0.95 (95% CI, 0.92-0.98), respectively.

CONCLUSIONS

Individuals with type 1 and 2 diabetes have greater risk for stenotic lesions, whereas risk for valvular regurgitation was lower in patients with type 2 diabetes. Patients with well-controlled cardiovascular risk factors continued to display higher risk for valvular stenosis, without a clear stepwise decrease in risk between various degrees of risk factor control.

Valvular Heart Disease Epidemiology

Valvular heart disease is a rapidly growing cause of global cardiovascular morbidity and mortality with diverse and evolving geographic distribution. The prevalence of rheumatic heart disease, the most common valvular heart disease (affecting approximately 41 million people), has been rising in developing nations, likely due to the expansion of the young adult population and the decrease in premature mortality that has resulted from improved access to antibiotics, microbiological testing, and echocardiography. Rheumatic heart disease has also been rising among the impoverished and, often, indigenous populations of developed nations, spurring public health initiatives that are aimed at alleviating healthcare disparities. Aortic valve stenotic disease is the most commonly occurring valvular pathology in developed nations (afflicting 9 million people worldwide) and its prevalence has been increasing with population aging and the increased prevalence of atherosclerosis. Aortic regurgitation is associated with diastolic, but not systolic, hypertension and it has likewise seen a rise in the developed world. Mitral regurgitation affects 24 million people worldwide, with great variability between and among nations. Primary mitral regurgitation arises as a consequence of myxomatous degeneration and mitral valve prolapse, which is largely due to genetic predispositions, while secondary mitral regurgitation accounts for 65% of cases and arises secondary to dilation and heart failure. Tricuspid regurgitation has become more prevalent in developed nations due to the increased usage of intracardiac pacemakers. Infective endocarditis prevalence has also grown in developed nations, likely due to population aging and the increased utilization of transcatheter valve replacement and prosthetic valves as interventions against the previously discussed valvular pathologies.

Sex differences in aortopathy and valve diseases among patients undergoing cardiac surgery

BACKGROUND

We aimed to study sex differences in aortopathy and valve disease among patients undergoing aortic valve replacement and/or surgery for ascending aortic aneurysm, and assess whether differences are specific for patients with bicuspid (BAV) compared to patients with tricuspid aortic valve (TAV).

METHODS

We used a single-center and observational cohort including 1,045 patients undergoing elective open-heart surgery for aortic valve disease and/or ascending aortic aneurysm at the Karolinska Hospital (Sweden).

RESULTS

Women (33.0%) were older than men (mean [SD]; 67.9 [11] years vs 62.5 [13] years for men; P < 0.001). No significant sex difference in prevalence of ascending aortic aneurysm was found according to absolute measures (P = 0.19), however, women had a greater dilation of the ascending aorta when normalized for body surface area (mean [SD], 21.8 [6.3] mm/m² vs 19.3 [4.4] mm/m² for men; P < 0.001). Among the 560 patients with BAV, women had significantly more AS (adjusted OR, 2.23; 95% CI, 1.19-4.20; P = 0.013) and less AI (adjusted OR 0.42; 95% CI, 0.23-0.78; P < 0.01); whereas no sex difference was found among patients with TAV.

CONCLUSIONS

In this large study of patients undergoing cardiac surgery, we found greater degree of aortic dilation in women compared to men suggesting a need for earlier monitoring of women. Moreover, women with BAV had a significantly higher prevalence of AS compared to men. These results describe the aorta and valvular characteristics of patients by sex and provide guidance regarding which patients might benefit from closer surveillance.

Transcatheter Aortic Valve Replacement in Pure Native Aortic Valve Regurgitation: Challenging Pathology Awaiting Specialized Devices

Patients with aortic incompetence frequently present with anatomical and pathological challenges such as elliptical dilated annulus, dilated aortic root, dilated ascending aorta, and with no calcification in the aortic cusps or annulus. Patients are commonly in graver clinical condition as a result of a long silent clinical course before overt congestive heart failure. All of the above make transcatheter therapies for native aortic valve regurgitation more challenging with poorer outcomes, escalating the risk of insufficient anchoring, prosthesis migration, and residual paravalvular leak compared with current transcatheter aortic valve replacement (TAVR) outcomes for aortic stenosis. There is a need for specialized TAVR devices to address this complex pathology. Surgical aortic valve replacement is the current treatment option and the gold standard for patients with aortic incompetence (AR). Currently, the specific off-label indication for TAVR in pure native AR could be a feasible and reasonable option, as a compassionate treatment is limited to inoperable patients and agreed on by the heart team.

Multiscale simulations of left ventricular growth and remodeling

Cardiomyocytes can adapt their size, shape, and orientation in response to altered biomechanical or biochemical stimuli. The process by which the heart undergoes structural changes-affecting both geometry and material properties-in response to altered ventricular loading, altered hormonal levels, or mutant sarcomeric proteins is broadly known as cardiac growth and remodeling (G&R). Although it is likely that cardiac G&R initially occurs as an adaptive response of the heart to the underlying stimuli, prolonged pathological changes can lead to increased risk of atrial fibrillation, heart failure, and sudden death. During the past few decades, computational models have been extensively used to investigate the mechanisms of cardiac G&R, as a complement to experimental measurements. These models have provided an opportunity to quantitatively study the relationships between the underlying stimuli (primarily mechanical) and the adverse outcomes of cardiac G&R, i.e., alterations in ventricular size and function. State-of-the-art computational models have shown promise in predicting the progression of cardiac G&R. However, there are still limitations that need to be addressed in future works to advance the field. In this review, we first outline the current state of computational models of cardiac growth and myofiber remodeling. Then, we discuss the potential limitations of current models of cardiac G&R that need to be addressed before they can be utilized in clinical care. Finally, we briefly discuss the next feasible steps and future directions that could advance the field of cardiac G&R.

Deep learning model to detect significant aortic regurgitation using electrocardiography: Detection model for aortic regurgitation

BACKGROUND

Aortic regurgitation (AR) is a common heart disease, with a relatively high prevalence of 4.9% in the Framingham Heart Study. Because the prevalence increases with advancing age, an upward shift in the age distribution may increase the burden of AR. To provide an effective screening method for AR, we developed a deep learning-based artificial intelligence algorithm for the diagnosis of significant AR using electrocardiography (ECG).

METHODS

Our dataset comprised 29,859 paired data of ECG and echocardiography, including 412 AR cases, from January 2015 to December 2019. This dataset was divided into training, validation, and test datasets. We developed a multi-input neural network model, which comprised a two-dimensional convolutional neural network (2D-CNN) using raw ECG data and a fully connected deep neural network (FC-DNN) using ECG features, and compared its performance with the performances of a 2D-CNN model and other machine learning models. In addition, we used gradient-weighted class activation mapping (Grad-CAM) to identify which parts of ECG waveforms had the most effect on algorithm decision making.

RESULTS

The area under the receiver operating characteristic curve of the multi-input model (0.802; 95% CI, 0.762-0.837) was significantly greater than that of the 2D-CNN model alone (0.734; 95% CI, 0.679-0.783; p<0.001) and those of other machine learning models. Grad-CAM demonstrated that the multi-input model tended to focus on the QRS complex in leads I and aVL when detecting AR.

CONCLUSIONS

The multi-input deep learning model using 12-lead ECG data could detect significant AR with modest predictive value.

Impaction of regurgitation jet on anterior mitral leaflet is associated with diastolic dysfunction in patients with bicuspid aortic valve and mild insufficiency: a cardiovascular magnetic resonance study

To assess the impact of regurgitant jet direction on left ventricular function and intraventricular hemodynamics in asymptomatic patients with bicuspid aortic valve (BAV) and mild aortic valve regurgitation (AR), using cardiac magnetic resonance (CMR) feature tracking and 4D flow imaging. Fifty BAV individuals were retrospectively selected: 15 with mild AR and posterior regurgitation jet (Group-PJ), 15 with regurgitant jet in other directions (Group-nPJ) and 20 with no regurgitation (Controls). CMR protocol included cine steady state free precession (SSFP) sequences and 4D Flow imaging covering the entire left ventricle (LV) cavity and the aortic root. Cine-SSFP images were analyzed to assess LV volumes, longitudinal and circumferential myocardial strain. Circumferential and longitudinal peak diastolic strain rate (PDSR) and peak diastolic velocity (PDV) were reduced in group PJ if compared to group nPJ and control group (PDSR = 1.10 ± 0.2 1/s vs. 1.34 ± 0.5 1/s vs. 1.53 ± 0.3 1/s, p:0.001 and 0.68 ± 0.2 1/s vs. 1.17 ± 0.2 1/s vs. 1.05 ± 0.4 1/s ; p < 0.001, PDV = − 101.6 ± 28.1 deg/s vs. − 201.4 ± 85.9 deg/s vs. − 221.6 ± 67.1 deg/s; p < 0.001 and − 28.1 ± 8 mm/s vs. − 38.9 ± 11.1 mm/s vs. − 43.6 ± 14.3 mm/s, p < 0.001, respectively), whereas no differences have been found in systolic strain values. 4D Flow images (available only in 9 patients) showed deformation of diastolic transmitral streamlines direction in group PJ compared to other groups. In BAV patients with mild AR, the posterior direction of the regurgitant jet may hamper the complete mitral valve opening, disturbing transmitral flow and slowing the LV diastolic filling.

Associations between aortic regurgitation severity and risk of incident myocardial infarction and stroke among patients with degenerative aortic valve disease: insights from a large Chinese population-based cohort study

OBJECTIVES

Few studies have explored whether the risk of myocardial infarction (MI) or stroke varies among patients with degenerative aortic valve disease (DAVD) with different severity of aortic regurgitation (AR) or not. Thus, a prospective study was conducted to elucidate the causal relationship between AR severity and risk of incident MI and stroke among patients with DAVD recruited from a general population in Northeast China.

DESIGN

Prospective cohort study.

SETTING

Community-based study carried out in rural areas of Northeast China.

METHODS

There were 3675 patients with DAVD aged ≥45 years eligible for the prospective study. During a median follow-up time of 4.64 years, 99 participants lost to follow-up. Cox regression analyses were used to investigate the association between baseline AR severity and the risk of incident MI or stroke.

RESULTS

In the final cohort of 3576 patients with DAVD, there were 3153 patients without AR (88.2%), 386 patients with mild AR (10.8%) and 37 patients with moderate or severe AR (1.0%). Multivariate analyses showed that, compared with participants without AR, those with moderate/severe AR were associated with 8.33 and 6.22-fold increased risk of MI and MI mortality, respectively. However, no significant associations between AR and the risk of stroke or stroke mortality were observed.

CONCLUSIONS

As compared with no AR, moderate/severe AR but not mild AR was an independent predictor for the risk of MI and MI mortality. AR was not significantly associated with stroke or stroke mortality, irrespective of AR severity. Secondary prevention strategies should be taken to delay the progression of DAVD and thus reduce the incidence of MI.

Long-term fate of moderate aortic regurgitation left untreated at the time of mitral valve surgery

OBJECTIVES

The appropriateness of moderate aortic regurgitation treatment during mitral valve (MV) surgery remains unclear. The goal of this study was to evaluate the immediate and long-term outcomes of patients with moderate aortic regurgitation at the time of MV surgery.

METHODS

We included 183 patients admitted to our institution for elective treatment of MV disease between 2004 and 2018, in whom moderate aortic regurgitation was diagnosed during preoperative evaluation. One hundred and twenty-two patients underwent isolated MV surgery (study group) whereas 61 patients underwent concomitant MV surgery and aortic valve replacement (control group).

RESULTS

One death (0.8%) occurred in the study group, and 3 deaths (4.8%) occurred in the control group (P = 0.52). The rate of the most common postoperative complication was similar between the 2 groups. At 12 years, the cumulative incidence function of cardiac death, with non-cardiac death as a competing risk, was 4.7 ± 2.8% in the study group; no cardiac deaths were observed in the control group (P = 0.078). At 6 and 12 years, in the study group, the cumulative incidence function of aortic valve reintervention, with death as a competing risk, was 2.5 ± 1.85% and 19 ± 7.1%, respectively.

CONCLUSIONS

The appropriate management of moderate aortic regurgitation at the time of MV surgery deserves a careful evaluation by balancing the reintervention rate with the age, the operative risk and the life expectancy of the patient. Our findings suggest that a patient-tailored approach is the key to achieving the best clinical outcome for each individual patient.

An unfortunate case of acute aortic regurgitation: Isolated aortic valve prolapse following a motor vehicle accident

We present an unfortunate case of severe acute aortic regurgitation (AR) following a motor vehicle accident (MVA) linked to isolated aortic valve prolapse, with no evidence of aortic root disruption or other valvular pathology missed on initial presentation. A 55-year-old gentleman, with known hypertension, was brought into the emergency department following a MVA, where he sustained severe intra-thoracic injuries. A bedside transthoracic echocardiogram (TTE) revealed a trileaflet aortic valve with evidence of mal-coaptation and severe AR. A computed tomography angiography of the thorax, however, failed to demonstrate evidence of dissection along the aortic root or ascending aorta. Following successful weaning off ventilatory support, the patient was discharged, but he presented back within a week with worsening dyspnoea and palpitations. Examination and investigation supported a diagnosis of acute heart failure with evident severe AR on repeat TTE. Transoesophageal echocardiography was performed, revealing prolapsed right and non-coronary cusps which were not seen in previous studies but absent evidence of the aortic root, ascending and descending aorta dilatation or dissection. Valvular complications rarely occur following blunt chest wall trauma, often involving right-sided valves due to their proximity to the sternum. Although aortic valve disruption can occur following MVAs, it is often associated with trauma to the aorta. Based on our literature search, there have been only a handful of reported cases of severe acute AR due to isolated prolapse or ruptured aortic valves in the absence of aortic valve perforation, aortic root disruption or dissection and other valvular abnormalities following trauma.

Counterpoint: challenges and limitations of transcatheter aortic valve implantation for aortic regurgitation

Transcatheter aortic valve implantation (TAVI) for isolated aortic regurgitation (AR) comprises <1.0% of all TAVI procedures performed in the USA. In this manuscript, we review the challenges, evidence and future directions of TAVI for isolated AR. There are no randomised clinical trials or mid-term data evaluating TAVI for isolated AR, and no commercially available devices are approved for this indication. Challenges in performing TAVI for isolated AR as opposed to aortic stenosis (AS) include: lack of a calcified anchoring zone for valve deployment, large and dynamic size of the aortic annulus and high stroke volume (during systole) and regurgitant volume (during diastole) across the aortic annulus during each cardiac cycle. Observational studies have shown that outcomes of TAVI for AR are worse than outcomes of TAVI for AS. However, newer generation TAVI devices may perform better than older generation devices in patients with AR. Two emerging valves (the JenaValve and the J-Valve) are designed with mechanisms to anchor in a non-calcified annulus, and these valves have shown promise for AR. Data on these devices are limited, and clinical investigation is ongoing. Randomised clinical trials are needed to establish TAVI as a safe and effective treatment for isolated AR.

Spontaneous Rupture of a Bicuspid Aortic Valve in a Middle-Aged Weightlifter

We describe a 58-year-old Caucasian male weightlifter who presented with acute shortness of breath after finishing his extensive exercise routine. Acute aortic valve regurgitation, due to spontaneous rupture of a bicuspid aortic valve, was diagnosed. Urgent surgical intervention was carried out, during which the bicuspid aortic valve was resected and replaced with an On-X bileaflet mechanical valve. The patient remains asymptomatic and is treated with warfarin, being in excellent physical condition 4 years after aortic valve replacement.

LEARNING POINTS

Spontaneous rupture of a bicuspid aortic valve, after heavy weightlifting, is a very rare cause of acute aortic valve regurgitation.Echocardiography is of vital importance to distinguish the reason for this medical emergency from other possible causes.Prompt diagnosis and surgical treatment can achieve excellent long-term results.

Transcriptional Profiling of Normal, Stenotic, and Regurgitant Human Aortic Valves

The genetic mechanisms underlying aortic stenosis (AS) and aortic insufficiency (AI) disease progression remain unclear. We hypothesized that normal aortic valves and those with AS or AI all exhibit unique transcriptional profiles. Normal control (NC) aortic valves were collected from non-matched donor hearts that were otherwise acceptable for transplantation (n = 5). Valves with AS or AI (n = 5, each) were collected from patients undergoing surgical aortic valve replacement. High-throughput sequencing of total RNA revealed 6438 differentially expressed genes (DEGs) for AS vs. NC, 4994 DEGs for AI vs. NC, and 2771 DEGs for AS vs. AI. Among 21 DEGs of interest, APCDD1L, CDH6, COL10A1, HBB, IBSP, KRT14, PLEKHS1, PRSS35, and TDO2 were upregulated in both AS and AI compared to NC, whereas ALDH1L1, EPHB1, GPX3, HIF3A, and KCNT1 were downregulated in both AS and AI (p < 0.05). COL11A1, H19, HIF1A, KCNJ6, PRND, and SPP1 were upregulated only in AS, and NPY was downregulated only in AS (p < 0.05). The functional network for AS clustered around ion regulation, immune regulation, and lipid homeostasis, and that for AI clustered around ERK1/2 regulation. Overall, we report transcriptional profiling data for normal human aortic valves from non-matched donor hearts that were acceptable for transplantation and demonstrated that valves with AS and AI possess unique genetic signatures. These data create a roadmap for the development of novel therapeutics to treat AS and AI.

The Face Is the Mirror of the Soul. The Cardiovascular Physical Exam Is Not Yet Dead!

Cardiac pathology can be congenital or acquired with underlying genetic predispositions. In this era of medicine there is a concern that the comprehensive physical examination doctors prided themselves on is becoming a lost art. Research studies have also revealed a decline in physical examination skills. The full clinical cardiovascular examination is indeed quite complex and does take significant time to master. It is critical that physicians be competent in the physical exam. Not identifying subtle clinical findings leading to missed or delayed diagnosis which can lead to significant morbidity and mortality. In this paper we intend to highlight the clinical cardiovascular findings that may be detected on patients even before initiating the physical exam. The head and neck visual examination may be quite revealing.

A Novel Aortic Regurgitation Model from Cusp Prolapse with Hemodynamic Validation Using an Ex Vivo Left Heart Simulator

Although ex vivo simulation is a valuable tool for surgical optimization, a disease model that mimics human aortic regurgitation (AR) from cusp prolapse is needed to accurately examine valve biomechanics. To simulate AR, four porcine aortic valves were explanted, and the commissure between the two largest leaflets was detached and re-implanted 5 mm lower to induce cusp prolapse. Four additional valves were tested in their native state as controls. All valves were tested in a heart simulator while hemodynamics, high-speed videography, and echocardiography data were collected. Our AR model successfully reproduced cusp prolapse with significant increase in regurgitant volume compared with that of the controls (23.2 ± 8.9 versus 2.8 ± 1.6 ml, p = 0.017). Hemodynamics data confirmed the simulation of physiologic disease conditions. Echocardiography and color flow mapping demonstrated the presence of mild to moderate eccentric regurgitation in our AR model. This novel AR model has enormous potential in the evaluation of valve biomechanics and surgical repair techniques. Graphical Abstract.

Structural Heart Disease Emergencies

Structural heart disease (SHD) emergencies include acute deterioration of a stable lesion or development of a new critical lesion. Structural heart disease emergencies can produce heart failure and cardiogenic shock despite preserved systolic function that may not respond to standard medical therapy and typically necessitate surgical or percutaneous intervention. Comprehensive Doppler echocardiography is the initial diagnostic modality of choice to determine the cause and severity of the underlying SHD lesion. Patients with chronic SHD lesions which deteriorate due to intercurrent illness (eg, infection or arrhythmia) may not require urgent intervention, whereas patients with an acute SHD lesion often require definitive therapy. Medical stabilization prior to definitive intervention differs substantially between stenotic lesions (aortic stenosis, mitral stenosis, left ventricular outflow tract obstruction) and regurgitant lesions (aortic regurgitation, mitral regurgitation, ventricular septal defect). Patients with regurgitant lesions typically require aggressive afterload reduction and inotropic support, whereas patients with stenotic lesions may paradoxically require β-blockade and vasoconstrictors. Emergent cardiac surgery for patients with decompensated heart failure or cardiogenic shock carries a substantial mortality risk but may be necessary for patients who are not eligible for catheter-based percutaneous SHD intervention. This review explores initial medical stabilization and subsequent definitive therapy for patients with SHD emergencies.

Impact of Aortoseptal Angle Abnormalities and Discrete Subaortic Stenosis on Left-Ventricular Outflow Tract Hemodynamics: Preliminary Computational Assessment

Discrete subaortic stenosis (DSS) is an obstruction of the left ventricular outflow tract (LVOT) due to the formation of a fibromuscular membrane upstream of the aortic valve. DSS is a major risk factor for aortic regurgitation (AR), which often persists after surgical resection of the membrane. While the etiology of DSS and secondary AR is largely unknown, the frequent association between DSS and aortoseptal angle (AoSA) abnormalities has supported the emergence of a mechanobiological pathway by which hemodynamic stress alterations on the septal wall could trigger a biological cascade leading to fibrosis and membrane formation. The resulting LVOT flow disturbances could activate the valve endothelium and contribute to AR. In an effort to assess this hypothetical mechano-etiology, this study aimed at isolating computationally the effects of AoSA abnormalities on septal wall shear stress (WSS), and the impact of DSS on LVOT hemodynamics. Two-dimensional computational fluid dynamics models featuring a normal AoSA (N-LV), a steep AoSA (S-LV), and a steep AoSA with a DSS lesion (DSS-LV) were designed to compute the flow in patient-specific left ventricles (LVs). Boundary conditions consisted of transient velocity profiles at the mitral inlet and LVOT outlet, and patient-specific LV wall motion. The deformation of the DSS lesion was computed using a two-way fluid-structure interaction modeling strategy. Turbulence was accounted for via implementation of the k-ω turbulence model. While the N-LV and S-LV models generated similar LVOT flow characteristics, the DSS-LV model resulted in an asymmetric LVOT jet-like structure, subaortic stenotic conditions (up to 2.4-fold increase in peak velocity, 45% reduction in effective jet diameter vs. N-LV/S-LV), increased vorticity (2.8-fold increase) and turbulence (5- and 3-order-of-magnitude increase in turbulent kinetic energy and Reynolds shear stress, respectively). The steep AoSA subjected the septal wall to a 23% and 69% overload in temporal shear magnitude and gradient, respectively, without any substantial change in oscillatory shear index. This study reveals the existence of WSS overloads on septal wall regions prone to DSS lesion formation in steep LVOTs, and the development of highly turbulent, stenotic and asymmetric flow in DSS LVOTs, which support a possible mechano etiology for DSS and secondary AR.

Abnormal cisatracurium pharmacodynamics and pharmacokinetics among patients with severe aortic regurgitation during anesthetic induction

Background

This study was designed to examine whether severe aortic regurgitation will affect the pharmacodynamics (PD) and pharmacokinetics (PK) of cisatracurium during anesthetic induction.

Methods

A total of 32 patients were divided into two groups: the AR group (n = 16) and the control group (n = 16). Arterial blood samples were drawn before and at 1, 2, 4, 6, 8, 10, 16 and 20 min after intravenous injection of 0.15 mg/kg cisatracurium. TOF tests were applied to determine the onset time of maximal muscle relaxation. The concentration of cisatracurium in plasma was determined by high-performance liquid chromatography.

Results

The onset time to maximal neuromuscular block was prolonged from 2.07 ± 0.08 min to 4.03 ± 0.14 min, which indicated that the PD responses to cisatracurium were significantly delayed in the AR group (P < 0.05) compared to the control group.

A conventional two-compartment PK model showed a higher plasma concentration of cisatracurium among the AR group with markedly reduced intercompartment transfer rate (K₁₂ = 0.19 ± 0.02 and K₂₁ = 0.11 ± 0.01 in the AR group vs. K₁₂₌0.26 ± 0.01 and K₂₁ = 0.19 ± 0.01 in the control group, P < 0.01) compared to the control group.

Conclusion

Backward blood flow during diastole in severe AR impaired distribution of cisatracurium from the central compartment to the peripheral compartment, which accounted for the lagged PD responses.

Findings in this study underlie the importance of muscular blockade monitoring among patients with severe aortic regurgitation during anesthetic induction.

Registration

Name of the registry: Abnormal Cisatracurium Pharmacodynamics and Pharmacokinetics among Patients with Severe Aortic Regurgitation during Anesthetic Induction. Trial registration number: ChiCTR1800019654. Date of registration: November 20th 2018.

Learning curve for transcatheter aortic valve replacement for native aortic regurgitation: Safety and technical performance study

Background

Transcatheter aortic valve replacement (TAVR) is a fundamentally new procedure for the treatment of native aortic regurgitation (AR). The number of cases needed to gain proficiency with the procedure is unknown.

Hypothesis

This study aimed to evaluate the learning curve for TAVR for native AR.

Methods

This study retrospectively reviewed a prospective database from 134 consecutive native AR patients who underwent the J‐valve TAVR system, which performed by a single team interventional cardiologist. The cumulative sum (CUSUM) method was used to analyze the learning curve. Patients were divided into two groups in chronological order, defined by the surgeon's early (group 1: the first 52 cases) and skilled (group 2: the next 82 cases) experience. Demographic data, intraoperative characteristics, and short‐term surgical outcomes were compared between the two groups.

Results

CUSUM plots revealed decreasing procedure time and fluoroscopy time after patients 52 and 43, respectively. The patient date consistently demonstrated that high‐risk scores and major perioperative parameters were comparable between the two groups. The use of contrast dye (group 1, 94.22 ± 30.07 mL; group 2, 70.43 ± 15.02 mL, P<.05), total procedure time (group 1, 84.96 ± 17.76 minutes; group 2, 59.95 ± 12.83 minutes, P<.05), and fluoroscopy time (group 1, 11.52 ± 3.81 minutes; group 2, 6.47 ± 1.53 minutes, P<.05) were significantly reduced in group 2. The overall device success rate in group 1 was 96.2% vs 96.3% in group 2 and remained high (P = 1.0). The overall 30‐day mortality was 3.8% in group 2 (group 1, 0 to group 2, 3.8%; P = .16). The complications rate, such as pulmonary hypertension, chronic kidney disease, and coronary artery disease were higher in group 2.

Conclusions

For a surgeon without previous TAVR experience, 52 cases of performance is the minimal requirement to gain the proficiency of TAVR for native AR. The skilled surgeons have been observed with reduced procedural time, fluoroscopy times, radiation exposure dose, and contrast volume usage. However, the overall prognosis was not significantly different between the two groups.

Mixed aortic valve disease treated with transcatheter aortic valve replacement in a high risk patient presenting with acute decompensated heart failure

Mixed aortic valve disease refers to the combination of aortic regurgitation (AR) and aortic stenosis (AS). Commonly etiologies include a bicuspid aortic valve, rheumatic heart disease, and endocarditis superimposed upon a stenotic aortic valve. Treatment depends upon the severity of disease, the presence of symptoms and the size and function of the left ventricle. We present a case of a young patient that presented with new onset acute decompensated heart failure with mixed aortic valve disease that was successful treated with transcatheter aortic valve replacement (TAVR). Invasive hemodynamics at baseline and following TAVR provide an insight into the characteristic features of mixed aortic valve disease. TAVR represents a new treatment option for critically ill patients deemed high risk or nonoperable for surgical aortic valve replacement.

Upregulated Autophagy in Calcific Aortic Valve Stenosis Confers Protection of Valvular Interstitial Cells

Autophagy serves as a cell survival mechanism which becomes dysregulated under pathological conditions and aging. Aortic valve thickening and calcification causing left ventricular outflow obstruction is known as calcific aortic valve stenosis (CAVS). CAVS is a chronic and progressive disease which increases in incidence and severity with age. Currently, no medical treatment exists for CAVS, and the role of autophagy in the disease remains largely unexplored. To further understand the role of autophagy in the progression of CAVS, we analyzed expression of key autophagy genes in healthy, thickened, and calcified valve tissue from 55 patients, and compared them with nine patients without significant CAVS, undergoing surgery for aortic regurgitation (AR). This revealed a upregulation in autophagy exclusively in the calcified tissue of CAVS patients. This difference in autophagy between CAVS and AR was explored by LC3 lipidation in valvular interstitial cells (VICs), revealing an upregulation in autophagic flux in CAVS patients. Inhibition of autophagy by bafilomycin-A1 led to a decrease in VIC survival. Finally, treatment of VICs with high phosphate led to an increase in autophagic activity. In conclusion, our data suggests that autophagy is upregulated in the calcified tissue of CAVS, serving as a compensatory and pro-survival mechanism.