Ventricular Outflow Tract Obstruction Research Articles

Clinical outcomes of transcatheter mitral valve replacement: two-year results of the CHOICE-MI Registry.

Transcatheter mitral valve replacement (TMVR) using dedicated devices is an alternative therapy for high-risk patients with symptomatic mitral regurgitation (MR). This study aimed to assess the 2-year outcomes and predictors of mortality in patients undergoing TMVR from the multicentre CHOICE-MI Registry. The CHOICE-MI Registry included consecutive patients with symptomatic MR treated with 11different dedicated TMVR devices at 31 international centres. The investigated endpoints included mortality and heart failure hospitalisation rates, procedural complications, residual MR, and functional status. Multivariable Cox regression analysis was applied to identify independent predictors of 2-year mortality. Atotal of 400patients, median age 76 years (interquartile range [IQR] 71, 81), 59.5% male, EuroSCORE II 6.2% (IQR 3.8, 12.0), underwent TMVR. Technical success was achieved in 95.2% of patients. MR reduction to ≤1+ was observed in 95.2% at discharge with durable results at 1 and 2years. New York Heart Association Functional Class had improved significantly at 1 and 2years. All-cause mortality was 9.2% at 30days, 27.9% at 1year and 38.1% at 2years after TMVR. Chronic obstructive pulmonary disease, reduced glomerular filtration rate, and low serum albumin were independent predictors of 2-year mortality. Among the 30-day complications, left ventricular outflow tract obstruction, access site and bleeding complications showed the strongest impact on 2-year mortality. In this real-world registry of patients with symptomatic MR undergoing TMVR, treatment with TMVR was associated with adurable resolution of MR and significant functional improvement at 2years. Two-year mortality was 38.1%. Optimised patient selection and improved access site management are mandatory to improve outcomes.

First-in-Human Transapical Beating-Heart Septal Myectomy in Patients With Hypertrophic Obstructive Cardiomyopathy

BackgroundTo simplify surgical septal reduction therapy for hypertrophic obstructive cardiomyopathy (HOCM), we developed a novel transapical beating-heart septal myectomy (TA-BSM) procedure. ObjectivesIn this study, we sought to evaluate the clinical utility of TA-BSM in a first-in-human trial. MethodsPatients with HOCM were enrolled if they presented with drug-refractory disabling symptoms. TA-BSM was performed via minithoracotomy with the use of our beating-heart myectomy device under echocardiographic guidance, without the use of cardiopulmonary bypass. Repeated resections were performed to tailor the extent of the septal myectomy for sufficient abolishment of left ventricular outflow tract (LVOT) obstruction and mitral regurgitation (MR). The primary outcome measure was procedural success, defined by resting/provoked LVOT gradient <30/50 mm Hg and residual MR grade ≤1+ (of 4+) at 3-month follow-up. ResultsA total of 47 patients aged 12 to 77 years were enrolled. Of the 46 patients who were followed for 3 months, 42 achieved procedural success. The maximal LVOT gradient decreased from 86 mm Hg (IQR: 67-114 mm Hg) at baseline to 19 mm Hg (IQR: 14-28 mm Hg) at 3 months. MR grade was ≤1+ in 3 patients at baseline and in 45 patients at 3 months. One patient died on postoperative day 10 owing to device-unrelated reasons. Other major adverse events included 1 delayed ventricular septal perforation and 1 intraoperative left ventricular apical tear. ConclusionsTA-BSM is a safe and efficient minimally invasive procedure for septal reduction of heterogeneous HOCM. Compared with conventional septal myectomy, TA-BSM provides real-time evaluation to guide resection while reducing surgical trauma. (Transapical Beating-Heart Septal Myectomy in Patients With Hypertrophic Obstructive Cardiomyopathy; NCT05332691)

Systolic anterior motion of the anterior mitral valve leaflet begins in subclinical hypertrophic cardiomyopathy.

Anterior mitral valve leaflet (AMVL) elongation is detectable in overt and subclinical hypertrophic cardiomyopathy (HCM). We sought to investigate the dynamic motion of the aorto-mitral apparatus to understand the behaviour of the AMVL and the mechanisms of left ventricular outflow tract obstruction (LVOTO) predisposition in HCM. Cardiovascular magnetic resonance imaging using a 1.5 Tesla scanner was performed on 36 HCM sarcomere gene mutation carriers without left ventricular hypertrophy (G+LVH-), 31 HCM patients with preserved ejection fraction carrying a pathogenic sarcomere gene mutation (G+LVH+), and 53 age-, sex-, and body surface area-matched healthy volunteers. Dynamic excursion of the aorto-mitral apparatus was assessed semi-automatically on breath-held three-chamber cine steady-state free precession images. Four pre-defined regions of interest (ROIs) were tracked: ROIPMVL: hinge point of the posterior mitral valve leaflet; ROITRIG: intertrigonal mitral annulus; ROIAMVL: AMVL tip; and ROIAAO: anterior aortic annulus. Compared with controls, normalized two-dimensional displacement-vs.-time plots in G+LVH- revealed subtle but significant systolic anterior motion (SAM) of the AMVL (P < 0.0001) and reduced longitudinal excursion of ROIAAO (P = 0.014) and ROIPMVL (P = 0.048). In overt and subclinical HCM, excursion of the ROITRIG/AMVL/PMVL was positively associated with the burden of left ventricular fibrosis (P < 0.028). As expected, SAM was observed in G+LVH+ together with reduced longitudinal excursion of ROITRIG (P = 0.049) and ROIAAO (P = 0.008). Dyskinesia of the aorto-mitral apparatus, including SAM of the elongated AMVL, is detectable in subclinical HCM before the development of LVH or left atrial enlargement. These data have the potential to improve our understanding of early phenotype development and LVOTO predisposition in HCM.

A Case of Cardiac Undifferentiated Pleomorphic Sarcoma With Right Ventricular Outflow Tract Obstruction.

Malignant tumors originating from the heart are extremely rare. Here, we report a case of severe right ventricular outflow tract (RVOT) stenosis in a 67 year-old woman caused by a massive intimal sarcoma that required venous-arterial extracorporeal membrane oxygenation to support systemic circulation. Surgical resection and RVOT reconstruction with tricuspid and pulmonary valve replacement were performed. The pathological diagnosis was cardiac undifferentiated pleomorphic sarcoma. Although the patient was discharged 65 days after surgery in good condition, she subsequently died from multiple metastases detected in the early phase after surgery.

Left Ventricular Noncompaction Masquerading as Hypertrophic Nonobstructive Cardiomyopathy

A 61-year-old male with no significant medical history presented with dyspnea on exertion for the past 3 months. Clinical examination findings and electrocardiogram showed sinus rhythm and left ventricular hypertrophy. The chest X-ray and basic laboratory tests were within the normal limits. A transthoracic echocardiogram was performed which showed left ventricular wall thickening involving the anterior wall, lateral wall, septum, and inferior wall in the basal, mid, and apical segments. The left ventricular apex showed disproportionately increased thickness. There was no left ventricular outflow tract (LVOT) turbulence or obstruction. Left ventricular angiogram showed prominent trabeculations with deep intertrabecular recesses. LVOT obstruction was ruled out. The patient then underwent cardiac magnetic resonance imaging, which showed features suggestive of left ventricular noncompaction.

Successful treatment of severe subaortic stenosis with left ventricular dysfunction in children

Link of Video Abstract: https://youtu.be/tHcMqNHfLyYBackground: Subaortic stenosis (SAS) is the second most common form of left ventricular outflow obstruction, accounting for 14% of LVOT obstruction in the general population. This obstruction is in the area of the heart under the aortic valve. While only a few cases have been reported in pediatrics, SAS is a gradually progressive disorder rarely seen at birth and infancy. This case study aims to evaluate the successful treatment of severe SAS with left ventricular dysfunction in children Case Presentation: We present the case of an 8-year-old boy who presented with shortness of breath on exertion and diaphoresis 3 months ago. Transthoracic echocardiography revealed severe aortic stenosis (PG 69.86 mmHg) with discrete tissue in the anterior LVOT and left ventricular systolic function decreased (EF Teich 29.44%), with global hypokinetic. Transesophageal echocardiography (TEE) results in severe subvalvular AS with a fixed subaortic membrane (PG 51.16 mmHg; Stenotic area 0.1 cm2), anterior to the aortic valve 1 cm long. There was mild mitral regurgitation and moderate tricuspid regurgitation. The patient then undergoes successful medical treatment and surgical subaortic membrane resection with tricuspid repair. After one year's operation, the patient remained stable, in good condition and free of symptoms. Conclusion: Subaortic stenosis is a gradually progressive disorder and could develop into heart failure with significant left ventricular dysfunction. Monitoring is an important aspect, given the nature of disease progression. Successful management of a patient with subaortic stenosis involves a multidisciplinary approach, including an early diagnosis, a comprehensive understanding of cardiac pathophysiology, risk factors of recurrence, optimal medical management and surgical strategy.

Effects of septal myectomy on left atrial and left ventricular function in obstructive hypertrophic cardiomyopathy.

Mechanical function of the left atrium (LA) and the left ventricle (LV) has been demonstrated to be a prognostic factor in patients with hypertrophic cardiomyopathy (HCM). We explore whether myocardial mechanical function can be improved by septal reduction therapy in symptomatic obstructive HCM. Among 65 patients who underwent septal myectomy for symptomatic obstructive HCM from 2006 to 2022, 44 were analysed after excluding those who underwent simultaneous valve repair or replacement or maze operation. LA and LV functional variables including LA strain and LV global longitudinal strain were evaluated by two-dimensional and speckle-tracking echocardiography and compared before and 1year after surgery. After septal myectomy, LA volume index (58.1±18.3 vs. 45.3±14.6mL/m2 , P=0.001) decreased significantly. As LV end-systolic dimension increased after surgery, the LV ejection fraction decreased (73.8±6.7 vs. 62.9±8.3%, P<0.001). LA strain (24.4±9.3 vs. 30.5±13.6%, P=0.004) improved after septal myectomy, but LV global longitudinal strain deteriorated (-12.6±3.6 vs. -11.6±4.3%, P=0.033), mainly related to worsening non-septal longitudinal strain (-14.4±4.3 vs. -10.9±8.4%, P=0.005). As haemodynamic loads due to LV outflow tract obstruction was relieved through surgical septal reduction therapy in patients with symptomatic obstructive HCM, there was a significant reduction in LA volume and restoration of LA mechanical dysfunction. However, LV mechanical dysfunction deteriorated even after surgical septal reduction therapy.

Late Outcomes of Konno-Rastan and Modified Konno for Left Ventricular Outflow Tract Obstruction

BackgroundWhile early outcomes of the Konno-Rastan and modified Konno procedures are known, long-term outcomes remain undetermined. Our objective was to examine long-term clinical and echocardiographic outcomes. MethodsRetrospective review was performed of patients undergoing Konno-Rastan and modified Konno for complex left ventricular outflow tract (LVOT) obstruction from January 1980 to January 2021. The Ross-Konno procedure was excluded due to its often limited ventriculotomy. ResultsA total of 92 patients were identified: 73 Konno-Rastan and 19 modified Konno. The modified Konno group was significantly younger (median [interquartile range, IQR]: 6, [2-12] years vs 16 [9-32] years, P = .001). LVOT obstruction was multilevel (39 of 92 [42.4%]), tunnel subaortic (35 of 92 [38.0%]), or aortic valve stenosis/annular hypoplasia (18 of 92 [19.6%]). Shone syndrome was present in 20 of 92 (21.7%) patients. Operative mortality was 7 of 92 (7.6%); 4 of 86 (4.7%) in elective vs 3 of 6 (50.0%) in urgent cases (P = .005). Median follow-up was 12 (IQR, 5-22) years. Aortic valve/LVOT mean gradient was 13 (IQR, 10-18) mm Hg at 1 year but gradually increased to 25 (IQR, 13-46) mm Hg at 10 years. Ejection fraction remained normal. Freedom from reoperation at 5 and 10 years was 77.2% and 58.4% among Konno-Rastan and 57.7% and 41.7% among modified Konno patients (P = .28), respectively. Overall survival at 5, 10, and 15 years was 82.9%, 76.3%, and 65.5%. Risk factors for mortality included older age, New York Heart Association class III/IV, longer cardiopulmonary bypass time, and multilevel LVOT obstruction. ConclusionsWhile LVOT obstruction is alleviated early, recurrent LVOT obstruction occurs over time after Konno-Rastan and modified Konno procedures. Additionally, despite preserved left ventricular systolic function, late overall survival is poor in this young population.

Unraveling the mystery of Takutsubo cardiomyopathy: a descendant of COVID-19 heart syndrome

Takutsubo, or stress cardiomyopathy (TCM) is one of the important cardiovascular disorders encountered during the COVID-19 pandemic. We performed a PubMed search of relevant articles and presented this review which included epidemiology, etiopathogenesis, diagnosis and treatment of this clinical disorder. Takutsubo is usually more common in women than men. COVID-19 infection or vaccination can incite severe emotional disorders such as anxiety and depression, which flames up impaired neural networks in the limbic system. This stirs up disorganized regulation of autonomic nervous system with predominance and excessive firing of sympathetic nervous system to the ventricular myocardium. Moreover, direct invasion and systemic effects of COVID-19 infection including hormonal influences, autoimmunity, cytokine storm and neighboring infections might also play a significant role in the manifestation of this disorder. It commonly presents signs and symptoms of left ventricular dysfunction. Although most cases are undergoing remission within a few weeks, complications such as LV outflow tract obstruction, thromboembolism and arrhythmias were also reported. Since clinical symptoms are non-specific, a high degree of clinical suspicion is warranted particularly with the co-existing COVID-19 infections. Clinicians often leaned upon battery of tests including ECG, echocardiography and CMR to rule out myocarditis and coronary artery disease. Supportive management including treatment of heart failure and any associated arrhythmias and thromboembolism. Recurrences are common, but the treatment of underlying psychiatric disorders, including relaxation techniques, is the key strategy to avoid future occurrences.

The Yasui operation: A single institutional experience over 30 years

ObjectiveThe Yasui operation was introduced in 1987 for patients with 2 adequate ventricles, a ventricular septal defect, and aortic atresia or interrupted aortic arch. Despite promising early outcomes, left ventricular outflow tract obstruction (LVOTO) remains a long-term concern. The purpose of this study is to report our institutional experience with the Yasui operation. MethodsWe retrospectively reviewed all patients undergoing the Yasui operation between 1989 and 2021. Results are reported as median with interquartile range (IQR). ResultsTwenty-five patients underwent a Yasui operation (19 primary), at 11 days (IQR, 7-218 days) of life and weight of 3 kg (IQR, 2.8-4.1 days). Fundamental diagnosis was ventricular septal defect/interrupted aortic arch in 11 patients and ventricular septal defect/aortic atresia in 14. Follow-up was 96% (24 out of 25) at 5 years (IQR, 1.4-14.7) with 92% survival. Freedom from LVOTO reoperation was 91% at late follow-up with 2 patients requiring baffle revision at 6 and 9 years. Latest echocardiogram showed 100% of patients had normal biventricular function and 87% (20 out of 23) less than mild LVOTO at 5 years (IQR, 2.3-14.9). Diagnosis, aortic valve morphology, and material used were not predictors of LVOTO. Freedom from right ventricle-to-pulmonary artery conduit reoperation was 48% at a median of 5 years (IQR, 1.4-14.7). Conduit type was not a predictor of reintervention. ConclusionsThe Yasui operation can be performed with low morbidity and mortality in patients with 2 acceptable-size ventricles and aortic atresia or interrupted aortic arch with severe LVOTO. Despite some burden of reoperation, midterm reoperation for LVOTO is not common and ventricular function is preserved.

Perioperative and Anesthetic Considerations in Pediatric Valvar and Subvalvar Aortic Stenosis.

Aortic stenosis (AS) is a common form of left ventricular outflow tract obstruction (LVOTO) in children with congenital heart disease. This review specifically considers the perioperative features of valvar (VAS) and subvalvar AS (subAS) in the pediatric patient. Although VAS and subAS share some clinical features and diagnostic approaches, they are distinct clinical entities with separate therapeutic options, which range from transcatheter intervention to surgical repair. We detail the pathophysiology of AS and highlight the range of treatment strategies with a focus on anesthetic considerations for the care of these patients before, during, and after intervention.

Transcatheter transseptal treatment of patients with severe mitral regurgitation using an atrial fixation mitral valve replacement technology

BackgroundMitral regurgitation (MR) is the most common valvular heart disease worldwide with a 5-year mortality rate of 50 % with medical therapy alone. Several transcatheter mitral valve replacement (TMVR) devices are being investigated in clinical trials. Early evidence has demonstrated clinical benefits with a reduction in heart failure symptoms, low rates of residual MR, and reverse remodeling of the left ventricle (LV) over time. However, high anatomical screen failure rates limit its applicability. The primary reasons for the anatomical screen failure are risk of LV outflow tract obstruction, large mitral valve annulus size, and the presence of mitral annular calcification. Our clinical experiences using an atrial only fixation TMVR technology delivered via a transfemoral-transseptal approach is described. MethodsThree consecutive patients with severe functional MR underwent TMVR implantation using an atrial only fixation technology and a low-profile transseptal delivery system. ResultsTechnical success was achieved in 100 % of the patients with a clinically significant reduction in MR. Longer-term follow-up (up to 6-months) has demonstrated a sustained reduction in MR and significant improvement in quality of life for all patients. ConclusionsLonger-term outcomes in our patients showed persistent reduction in MR, sustained implant performance, and notable improvements in NYHA Class and quality of life. There were no major adverse events. Follow-up CT data showed no evidence of device-related thrombosis, with stable valve position and integrity. The atrial fixation TMVR technology may have benefits in preserving the dynamics of the native mitral valve annulus thereby reducing the overall risk of LVOT obstruction. Short AbstractWe present a single-center experience of three consecutive patients with severe functional MR treated with the AltaValve using a low-profile transseptal delivery system. A clinically significant reduction in mitral regurgitation was achieved in all patients, and longer-term follow-up has demonstrated sustained clinical benefits.

The Role of Cardiopulmonary Exercise Testing in Hypertrophic Cardiomyopathy.

This review emphasizes the importance of cardiopulmonary exercise testing (CPET) in patients diagnosed with hypertrophic cardiomyopathy (HCM). In contrast to standard exercise testing and stress echoes, which are limited due to the ECG changes and wall motion abnormalities that characterize this condition, CPET allows for the assessment of the complex pathophysiology and severity of the disease, its mechanisms of functional limitation, and its risk stratification. It is useful tool to evaluate the risk for sudden cardiac death and select patients for cardiac resynchronization therapy (CRT), cardiac transplantation, or mechanical circulatory support, especially when symptomatology and functional status are uncertain. It may help in differentiating HCM from other forms of cardiac hypertrophy, such as athletes' heart. Finally, it is used to guide and monitor therapy as well as for exercise prescription. It may be considered every 2 years in clinically stable patients or every year in patients with worsening symptoms. Although performed only in specialized centers, CPET combined with echocardiography (i.e., CPET imaging) and invasive CPET are more informative and provide a better assessment of cardiac functional status, left ventricular outflow tract obstruction, and diastolic dysfunction during exercise in patients with HCM.

Percutaneous transluminal septal myocardial ablation for right ventricular outflow tract obstruction with repaired tetralogy of Fallot.

Percutaneous transluminal septal myocardial ablation for right ventricular outflow tract obstruction with repaired tetralogy of Fallot.

Exaggerated myocardial torsion may contribute to dynamic left ventricular outflow tract obstruction in hypertrophic cardiomyopathy.

Dynamic left ventricular (LV) outflow tract obstruction (LVOTO) is associated with symptoms and increased risk of developing heart failure in hypertrophic cardiomyopathy (HCM). The association of LVOTO and LV twist mechanics has not been well studied in HCM. The aim of the study was to compare the pattern of LV twist in patients with HCM associated with asymmetrical septal hypertrophy with and without LVOTO. Echocardiography (including speckle tracking) was performed in 212 patients with HCM, divided according to the absence (n = 130) or presence (n = 82) of LVOTO (defined as peak pressure gradient ≥30 mmHg either at rest and/or with Valsalva manoeuvre). Patients with LVOTO were older, had smaller LV dimensions, a higher LV ejection fraction (LVEF), a longer anterior mitral valve leaflet length, and a higher early transmitral pulsed wave to septal tissue Doppler velocity ratio (E/E'). A univariate analysis showed that peak twist was significantly higher in patients with LVOTO compared with patients without LVOTO (19.7 ± 7.3 vs. 15.7 ± 6.0, P = 0.00015). Peak twist was similarly enhanced in patients with LVOTO, manifesting only during Valsalva (19.2 ± 5.6, P = 0.007) and patients with resting LVOTO (19.9 ± 8.0, P = 0.00004) compared with patients without LVOTO (15.7 ± 6.0). A stepwise forward logistic regression analysis showed that LVEF, LV end-systolic dimension indexed to body surface area, anterior mitral valve leaflet length, E/E', and peak twist were all independently associated with LVOTO. This study demonstrates that increased peak LV twist is independently associated with LVOTO in patients with HCM. Peak twist was similarly exaggerated in patients with only latent LVOTO, suggesting that it may play a contributory role to LVOTO in HCM.

Morphology of hypertrophied basal septum contributes to left ventricular outflow tract obstruction in patients with hypertrophic cardiomyopathy: a retrospective case-control study.

Detailed assessment of basal septal morphology is essential for understanding the morphological mechanism of left ventricular outflow tract (LVOT) obstruction. We aimed to analyze the morphological alterations of the basal septum (BS) and its surrounding structures and explore their role in LVOT obstruction (LVOTO) in patients with hypertrophic cardiomyopathy (HCM). During January 2019 and December 2019, 239 patients were diagnosed with HCM at Fuwai Hospital. We retrospectively reviewed echocardiographic data sets from 105 consecutive patients with HCM [64 with hypertrophic obstructive cardiomyopathy (HOCM) and 41 with hypertrophic non-obstructive cardiomyopathy (HNOCM)] and 28 healthy controls. For quantitatively assessing the basal septal morphology, a novel measurement method was used to obtain the IVSa (the area of the BS protruding into the LVOT), LA (the largest distance of the BS protruding into the LVOT), LB (IVSa length in the direction perpendicular to the LA), and S-IVSa (IVSa divided by LB). Echocardiographic parameters associated with LVOTO were analyzed using multivariable logistic regression analyses. There was no significant difference in the maximal basal septal thickness between the HOCM and HNOCM patients (P>0.99). Among the three groups, there were significant differences in the length of the anterior and posterior mitral leaflets (AML and PML), the angle between the mitral valve orifice and ascending aorta (MV-AO) angle, IVSa, LA, LB, and S-IVSa (all P<0.001). Compared with HNOCM patients, HOCM patients had significantly longer AML and PML, as well as larger MV-AO angle, IVSa, LA, and S-IVSa (P<0.001, P<0.001, P<0.001, P=0.002, P<0.001, and P=0.03, respectively). In the multivariate analysis, AML, MV-AO angle, IVSa, and S-IVSa were associated with LVOTO {odds ratio (OR) [95% confidence interval (CI)]: 0.649 (0.462-0.911), P=0.01; 0.842 (0.768-0.923), P<0.001; 1.025 (1.001-1.049), P=0.04; and 0.276 (0.101-0.754), P=0.01, respectively}. Morphological alterations of the BS relative to the LVOT may provide additional value for estimating the extent of LVOTO. The length of AML, MV-AO angle, IVSa, and S-IVSa were associated with LVOTO.

Evaluation of diastolic dysfunction in children with hypertrophic cardiomyopathy and its relationship with development of myocardial fibrosis

BackgroundPatients with hypertrophic cardiomyopathy may develop symptoms of shortness of breathing due to diastolic dysfunction which is not related to the severity of left ventricular outflow tract obstruction. As these patients usually develop a non-ischemic pattern of myocardial fibrosis, this may represent a mechanism for increased myocardial stiffness leading to impaired diastolic filling. The study aimed to determine the prevalence of myocardial fibrosis assessed by magnetic resonance imaging in children with hypertrophic cardiomyopathy and to evaluate its relationship with echocardiographic parameters including left ventricle diastolic dysfunction and to find echocardiographic indices which correlates with myocardial fibrosis as detected by cardiac magnetic resonance. A cross-sectional study was done for data of 50 children with hypertrophic cardiomyopathy from July 2018 to July 2021, patients were divided into (group 1) having myocardial fibrosis and (group 2) with no myocardial fibrosis, and results of echocardiographic parameters were compared between the two groups.ResultsResults showed strong relationship between presence of myocardial fibrosis and each of the following: Interventricular septum thickness, lower lateral and septal early diastolic tissue velocities (E′), E/E′ ratio, presence of left ventricular out flow tract obstruction and the grade of diastolic dysfunction.ConclusionsThe trans-mitral lateral and septal E/E′ (early mitral inflow to early diastolic mitral annular velocity ratio) allows early detection of left ventricular diastolic dysfunction in children with hypertrophic cardiomyopathy. The prevalence of diastolic dysfunction is higher in obstructive hypertrophic cardiomyopathy. The diastolic dysfunction severity is higher in patients with myocardial fibrosis.

Feasibility and safety of transseptal transcatheter mitral valve replacement for severe mitral regurgitation

A prospective, single-center, single-arm, and open-design study was performed to evaluate the feasibility and safety of transseptal transcatheter mitral valve replacement in the treatment of severe mitral regurgitation. Patients with symptomatic moderate-severe or severe mitral regurgitation at high-surgical risk and anatomically appropriate for the HighLife transseptal mitral valve replacement (TSMVR) system in West China Hospital, Sichuan University from December 2021 to August 2022 were enrolled. Four patients (1 male and 3 females) with severe mitral regurgitation were included, with a median age of 68.5 (64.0-77.0) years and a median Society of Thoracic Surgeons (STS) score of 8.1% (6.4%-8.9%). Technical success was achieved in all the patients. There was no residual mitral regurgitation, paravalvular leakage, or left ventricular outflow tract obstruction. Three major cardiovascular and cerebrovascular adverse events occurred within 30 days after the procedure, including ventricular tachycardia, iatrogenic atrial septal defect closure, and heart failure readmission. The current study preliminarily demonstrates that transcatheter mitral valve replacement using the HighLife system via the transseptal approach for severe mitral regurgitation is feasible and relatively safe.

Characterization of ultrasound and postnatal pathology in fetuses with heterotaxy syndrome.

To explore the diagnostic clues and abnormality spectrum of heterotaxy syndrome by prenatal ultrasonography and postnatal verification. The prenatal ultrasonic data of 88 heterotaxy syndrome fetuses were analyzed retrospectively as left isomerism (LI) and right isomerism (RI). Prenatal ultrasound compared with the anatomical casting of the fetal body after labor induction, and the confirmatory postnatal diagnosis after delivery. Fetal LI showed typical malformations of gastric vesicles on different sides from the heart, absence of hepatic segment of the inferior vena cava (IVC), abdominal aorta (AO) parallel with the azygos vein (AV), bilateral left bronchus, bilateral left atrial appendages, and polysplenia; intracardiac malformations of AV septal defects (AVSD), single atrium (SA), left ventricular outflow tract obstruction (LVOTO), and double-outlet right ventricle (DORV); and cardiac conduction abnormalities of sinus bradycardia and AV blockage. Fetal RI reported typical malformations of gastric vesicles on different sides from the heart, juxtaposition of the IVC with AO, anomalous pulmonary venous connection (APVC), asplenia, and bilateral right atrial appendages; intracardiac malformations of AVSD, SA, single ventricle, pulmonary atresia and stenosis, and DORV. The postnatal verification revealed 3 malformations misdiagnoses and 4 malformations missed diagnoses in LI fetuses and 10 misdiagnoses and 8 missed diagnoses in RI fetuses. The proposed five-step prenatal ultrasonography has an important diagnostic value for the identification and classification of heterotaxy syndrome. The different sides of gastric vesicles and cardiac apex are important diagnostic clues for heterotaxy syndrome, featuring disconnected or hypoplastic IVC, typical complex cardiac malformation, and atrioventricular block in fetal LI, and shown APVC, juxtaposition of IVC and AO, and intracardiac malformations such as AVSD, DORV, and LVOTO in fetal RI.

Rightward imbalanced pulmonary perfusion predicts better exercise stroke volume in children after Fallot repair

BackgroundResidual lesions following Fallot repair are primarily pulmonary regurgitation and right ventricular outflow tract obstruction. These lesions may impact exercise tolerance, particularly because of a poor increase in left ventricular stroke volume. Pulmonary perfusion imbalance is also common, but its effect on cardiac adaptation to exercise is not known. AimTo assess the association between pulmonary perfusion asymmetry and peak indexed exercise stroke volume (pSVi) in young patients. MethodsWe retrospectively studied 82 consecutive patients with Fallot repair (mean age 15.2±3.8 years) who underwent echocardiography, four-dimensional flow magnetic resonance imaging and cardiopulmonary testing with pSVi measurement by thoracic bioimpedance. Normal pulmonary flow distribution was defined as right pulmonary artery perfusion between 43 and 61%. ResultsNormal, rightward and leftward flow distributions were found in 52 (63%), 26 (32%) and four (5%) patients, respectively. Independent predictors of pSVi were right pulmonary artery perfusion (β=0.368, 95% confidence interval [CI] 0.188 to 0.548; P=0.0003), right ventricular ejection fraction (β=0.205, 95% CI 0.026 to 0.383; P=0.049), pulmonary regurgitation fraction (β=–0.283, 95% CI –0.495 to –0.072; P=0.006) and Fallot variant with pulmonary atresia (β=–0.213, 95% CI –0.416 to –0.009; P=0.041). The pSVi prediction was similar when the categorical variable right pulmonary artery perfusion>61% was used (β=0.210, 95% CI 0.006 to 0.415; P=0.044). ConclusionIn addition to right ventricular ejection fraction, pulmonary regurgitation fraction and Fallot variant with pulmonary atresia, right pulmonary artery perfusion is a predictor of pSVi, in that rightward imbalanced pulmonary perfusion favours greater pSVi.