Ventricular Outflow Tract Obstruction Research Articles

Mitral Geometry on the Mechanism of Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy

The mechanism of left ventricular outflow tract obstruction (LVOTO) is complex in hypertrophic cardiomyopathy (HCM). We aimed to evaluate the impact of mitral valve geometry on LVOTO by echocardiography. The study population comprised 177 consecutive patients with HCM. Morphological findings of left ventricular hypertrophy and LVOTO-related abnormalities were assessed by comprehensive transthoracic echocardiography. Aortomitral angle, mitral leaflet length, and coaptation height were measured and analyzed at rest. Multivariable stepwise forward logistic regression analysis was performed to identify geometric predictors of LVOTO. One hundred thirty-seven patients had an LVOT gradient ≥30mm Hg. Multivariable logistic regression showed that aortomitral angle (odds ratio [OR], 0.89; 95% CI, 0.83-0.95, P<.001), coaptation height (OR, 1.96; 95% CI, 1.41-2.72, P<.001), and accessory mitral valve chordae tendineae (OR, 13.1; 95% CI, 4.32-39.95; P<.001) were independently associated with LVOTO. Receiver operating characteristic analysis showed that the area under the curve of mitral coaptation height was higher (area under the curve=0.815) than the other 2 indicators (P<.05). Mitral coaptation height, aortomitral angle, and accessory mitral valve chordae tendineae were important predictors of SAM and LVOTO in HCM independent of septal hypertrophy.

Primary vs Staged Biventricular Repair for Neonatal IAA with VSD and LVOTO

BackgroundThis study sought to determine the safety of primary and staged biventricular repair in neonates with interrupted aortic arch (IAA), ventricular septal defect (VSD), and severe left ventricular outflow tract obstruction (LVOTO). MethodsPatients with a fundamental diagnosis of IAA and VSD between 2015 and 2020 were extracted from The Society of Thoracic Surgeons National Database by using a Participant User File. The objective was to compare outcomes for neonates undergoing primary and staged Yasui and Ross operations. Primary end points were operative morbidity and mortality. ResultsDuring the study period, 11.4% (123 of 1079) of neonates with a fundamental diagnosis of IAA and VSD underwent operations indicative of severe LVOTO. Of these patients, 42 (34%) underwent primary biventricular repair (Yasui or Ross/Ross-Konno), and 81 underwent a potential staging procedure (Norwood or hybrid stage I). No differences were observed in preoperative patient characteristics between groups. Neonates undergoing staged repair experienced fewer major complications (0 vs 1; P = .04) and total complications (2 vs 4; P = .02), but similar operative mortality (5% vs 12%; P = .27) as neonates undergoing primary repair. A total of 58 patients undergoing Rastelli, biventricular repair, Yasui, or Ross/Ross-Konno operations with a diagnosis of IAA and VSD and history of neonatal Norwood or hybrid stage I procedures were also identified. Operative mortality for second-stage biventricular conversion operations was 2% (1 of 58). Only 4 centers performed 1 or more complex biventricular repairs for IAA and VSD with LVOTO per year. ConclusionsPrimary and staged biventricular repairs for IAA and VSD with LVOTO are associated with low operative mortality in the modern era and may be favorable to long-term single-ventricle palliation.

Retrofitting the Heart: Explaining the Enigmatic Septal Thickening in Hypertrophic Cardiomyopathy.

Hypertrophic cardiomyopathy is the most common genetic cardiac disease and is characterized by left ventricular hypertrophy. Although this hypertrophy often associates with sarcomeric gene mutations, nongenetic factors also contribute to the disease, leading to diastolic dysfunction. Notably, this dysfunction manifests before hypertrophy and is linked to hypercontractility, as well as nonuniform contraction and relaxation (myofibril asynchrony) of the myocardium. Although the distribution of hypertrophy in hypertrophic cardiomyopathy can vary both between and within individuals, in most cases, it is primarily confined to the interventricular septum. The reasons for septal thickening remain largely unknown. In this article, we propose that alterations in muscle fiber geometry, present from birth, dictate the septal shape. When combined with hypercontractility and exacerbated by left ventricular outflow tract obstruction, these factors predispose the septum to an isometric type of contraction during systole, consequently constraining its mobility. This contraction, or more accurately, this focal increase in biomechanical stress, prompts the septum to adapt and undergo remodeling. Drawing a parallel, this is reminiscent of how earthquake-resistant buildings are retrofitted with vibration dampers to absorb the majority of the shock motion and load. Similarly, the heart adapts by synthesizing viscoelastic elements such as microtubules, titin, desmin, collagen, and intercalated disc components. This pronounced remodeling in the cytoskeletal structure leads to noticeable septal hypertrophy. This structural adaptation acts as a protective measure against damage by attenuating myofibril shortening while reducing cavity tension according to Laplace Law. By examining these events, we provide a coherent explanation for the septum's predisposition toward hypertrophy.

A Modified Tip-to-Base LAMPOON to Prevent Left Ventricular Outflow Tract Obstruction in Valve-in-Ring or Valve-in-Valve Transcatheter Mitral Valve Replacement.

The Laceration of the Anterior Mitral leaflet to Prevent Outflow ObtructioN (LAMPOON) procedure may be performed from the leaflet tip to base to prevent left ventricular outflow tract obstruction (LVOTO) in patients with high-risk anatomy undergoing valve-in-valve (VIV) or valve-in-(complete)-ring (VIR) transcatheter mitral valve replacement (TMVR). Thirteen consecutive patients (6 females, average age 67.7 years) with a mean left ventricular ejection fraction of 60%, a median STS score of 3.2%, and degenerative surgical mitral bioprosthesis or ring were treated with a combined, single-stage procedure of preventive LAMPOON and trans-septal TMVR with SAPIEN 3 valves (Edwards Lifesciences, Irvine, CA). Under real-time 3-dimensional transesophageal echocardiography (RT 3D-TEE) guidance, we included the rendezvous technique in the LAMPOON procedure, and all 13 patients were successfully treated by tip-to-base LAMPOON and TMVR. The use of a modified LAMPOON procedure, aided by a rendezvous technique and guided by RT 3D-TEE imaging, offers precise guidance for positioning and aligning the guidewire. This approach not only reduces the need for fluoroscopy and shortens procedure times, but also significantly increases the likelihood of a successful outcome. Importantly, none of the patients in our study experienced unintentional aortic or aortic valve injuries, nor did they develop significant LVOTO following TMVR. In 11 of the 13 (85%) patients, we used a transcatheter SENTINELTM cerebral protection device (Boston Scientific, Marlborough, MA) for stroke prevention and capture of debris ≥ 2 mm were detected in 8/11 (73%) of the cases. Utilizing intra-operative RT 3D-TEE in conjunction with the rendezvous technique can make the tip-to-base LAMPOON procedure even safer and more effective for patients undergoing VIV or VIR TMVR. Our study also suggests that cerebral protection is indicated in patients undergoing TMVR.

Interventional management of an unusual cause of cyanosis in repaired tetralogy of Fallot

ABSTRACT Arterial desaturation following surgical repair of tetralogy of Fallot (TOF) is rare. In most instances, it results from residual right ventricular outflow tract obstruction, causing right-to-left shunt across residual interatrial or interventricular communication. In this report, we present an unusual scenario of arterial desaturation due to a recanalized left cardinal vein in a child with repaired TOF. We also discuss stepwise evaluation that led to successful identification and occlusion of the abnormal venous channel by percutaneous device closure.

New echocardiographic screening tool for left ventricular tract obstruction risk assessment in TMVR

BackgroundTranscatheter mitral valve replacement (TMVR) is an alternative to conventional surgery to treat severe mitral disease but its use is limited by the risk of left ventricular outflow tract obstruction (LVOTO). Screening depends on ECG-gated computed tomography (CT) that is not widely available and requires contrast. We developed and validated a transthoracic echocardiographic (TTE) method to assess the risk of LVOTO after TMVR with the Tendyne System. MethodsWe measured the LVOT longitudinal area on preoperative TTE dataset of patients screened for TMVR. The LVOT was measured as the box-area included by the aortic valve annulus, the anterior mitral leaflet (AML), the c-septum distance line, and the respective length of the AML on the interventricular septum. We analyzed the correlation between the TTE LVOT-box and the CT-measured neoLVOT area. Prediction performance for eligible patients was tested with ROC curves. ResultsThirty-nine patients were screened, out of 14 patients (36%) not eligible for TMVR, 8 had risk of LVOTO. We found a linear correlation between the TTE LVOT-box and the CT-measured Neo-LVOT (r = 0.6, p = 0.002). ROC curve showed that the method is specific and sensitive and the cut-off value of the measure LVOT-box is 350 mm2. ConclusionsThe proposed method is reliable to evaluate the risk of LVOTO after TMR with the Tendyne System. It is quick and easy and can be used as a first-line assessment in the outpatient clinic. Patients with LVOT-box <350 mm2 should not be further screened with ECG-gated cardiac CT.

The results of modified Konno procedure for complex left ventricular outflow tract obstruction

Background: Complex left ventricular outflow tract obstruction (c- LVOTO) necessitates an diagnosis, follow – up and operation to void severe left ventricular outflow tract obstruction. There are some procedures, for example: Aor–ventriculoplasty (the Konno-Rastan procedure), apicoaortic conduit… However, all procedures require a prosthetic or allogeneic valve as well as postoperative anticoagulation therapy, reoperation, or both, the modified Konno procedure which avoid that problems. Methods: This was a review of seri c-LVOTO cases who underwent modified Konno procedure from 1/2014 to 12/2022. There were 8 patients ( 5 males and 3 females). The mean age was 5,6 years (range from 1 – 10 years) and the mean weight was 12,6 kilograms. The gradient of left ventricular outflow tract was 43 mmHg. All aortic valve were competents. Results: The time of cardiopulmonary bypass, aortic clamping were: 76 mins; 56 mins. There was no mortality. The gradient postopration of LVOT and RVOT were 14 mmHg and 8 mmHg. During follow-up time 61 months after surgery, there was no late death. The gradient of LVOT and RVOT were 10 mmHg and 6 mmHg Conclusion: The modified Konno procedure had good results with low gradient of LVOT and RVOT

Perioperative management and outcomes for posterior spinal fusion in patients with Friedreich ataxia: A single-center, retrospective study.

Friedreich ataxia is a rare genetic disorder associated with progressive mitochondrial dysfunction leading to widespread sequelae including ataxia, muscle weakness, hypertrophic cardiomyopathy, diabetes mellitus, and neuromuscular scoliosis. Children with Friedreich ataxia are at high risk for periprocedural complications during posterior spinal fusion due to their comorbidities. To describe our single-center perioperative management of patients with Friedreich ataxia undergoing posterior spinal fusion. Adolescent patients with Friedreich ataxia presenting for spinal deformity surgery between 2007 and 2023 were included in this retrospective case series performed at the Children's Hospital of Philadelphia. Perioperative outcomes were reviewed along with preoperative characteristics, intraoperative anesthetic management, and postoperative medical management. Seventeen patients were included in the final analysis. The mean age was 15 ± 2 years old and 47% were female. Preoperatively, 35% were wheelchair dependent, 100% had mild-to-moderate hypertrophic cardiomyopathy with preserved systolic function and no left ventricular outflow tract obstruction, 29% were on cardiac medications, and 29% were on pain medications. Intraoperatively, 53% had transesophageal echocardiography monitoring; 12% had changes in volume status on echo but no changes in function. Numerous combinations of total intravenous anesthetic agents were used, most commonly propofol, remifentanil, and ketamine. Baseline neuromonitoring signals were poor in four patients and one patient lost signals, resulting in 4 (24%) wake-up tests. The majority (75%) were extubated in the operating room. Postoperative complications were high (88%) and ranged from minor complications like nausea/vomiting (18%) to major complications like hypotension/tachycardia (29%) and need for extracorporeal membrane oxygenation support in one patient (6%). Patients with Friedreich ataxia are at high risk for perioperative complications when undergoing posterior spinal fusion and coordinated multidisciplinary care is required at each stage. Future research should focus on the utility of intraoperative echocardiography, optimal anesthetic agent selection, and targeted fluid management to reduce postoperative cardiac complications.

Simultaneous transapical transcatheter aortic and mitral valve replacement in patients with severe valve dysfunction: initial experience.

Simultaneous transcatheter mitral valve in valve (VIV) replacement and aortic valve replacement experience is limited. We report our initial experience with simultaneous transapical transcatheter aortic and mitral valve replacement in patients with severe valve dysfunction. A total of 8 patients had simultaneous transcatheter heart valve implants for severe mitral bioprosthesis failure (VIV), with a second valve procedure that included native aortic regurgitation (n = 3) or degenerated bioprostheses in the aortic position (n = 5). All patients were treated with a self-expandable J-valve transcatheter valve, using the transapical approach. The mean age of the patients was 73.1 ± 6.2years. The mean Society of Thoracic Surgeons score was 13.8 ± 6.3%. Device success was 100% according to Valve Academic Research Consortium-2 criteria. No other procedure-associated complications occurred, including left ventricular outflow tract obstruction and valve migration. The mean hospital lengths of stay after the procedure were 11.5 ± 8.0days. No deaths occurred at 30days. At a median follow-up period of 28.7 ± 22.3months, no patients died. All patients were in New York Heart Association functional classes I-II. Echocardiographic parameters at follow-up showed a normofunctioning J valve in the mitral position and a mean max mitral flow velocity of 2.0 ± 0.5m/s; the J valve in the aortic position was also normofunctioning, and the mean max aortic flow velocity was 2.3 ± 0.5m/s. Simultaneous transapical transcatheter aortic and mitral valve replacement using the self-expandable J valve appears to be a feasible and effective alternative to redo surgery.

Long-term outcomes after the arterial switch operation.

The aims of this study were to evaluate the 16-year experience with arterial switch operation at Beijing Children's Hospital and to determine early and late mortality and late morbidity, to explore risk factors for late complications and reintervention, and finally to evaluate whether the neoaorticsinotubular junction reconstruction technique reduces late complications of arterial switch operation. The clinical data of 185 patients with transposition of the great arteries who underwent arterial switch operation in Beijing Children's Hospital from January 2006 to January 2022 and 30 patients who underwent modified arterial switch operation with neoaorticsinotubular junction reconstruction technique in Fuwai Hospital during the same period were retrospectively analysed. Propensity score matching was also used to match the neoaorticsinotubular junction reconstruction patients in Fuwai Hospital with 30 non-neoaorticsinotubular junction reconstruction patients in Beijing Children's Hospital. There were 13 early deaths (7.03%) and five late deaths (3.01%). Nineteen patients (11.45%) developed new aortic valve regurgitation and 28 patients (16.87%) developed aortic root dilation. Late right ventricular outflow tract obstruction occurred in 33 patients (19.88%). Late reintervention occurred in 18 cases (10.84%). Multivariate analysis showed that aorto-pulmonary diameter mismatch, previous pulmonary artery banding, and mild moderate or above new aortic valve regurgitation at discharge were independent risk factors for late new aortic valve regurgitation and aortic root dilation. Low surgical weight was an independent risk factor specific to new aortic valve regurgitation, and bicuspid native pulmonary valve was an independent risk factor specific to aortic root dilation. Older surgical age and aortic root dilation were independent risk factors for late right ventricular outflow tract obstruction. Older surgical age, operation before 2014, late right ventricular outflow tract obstruction, and late aortic root dilation were independent risk factors for late intervention. Propensity score matching showed that new aortic valve regurgitation and aortic root dilation were not followed up in the neoaorticsinotubular junction reconstruction group, while seven cases of aortic root dilation and five cases of new aortic valve regurgitation occurred in the non-neoaorticsinotubular junction reconstruction group, respectively, and the differences were statistically significant (P = 0.003; P = 0.015). The increased incidence of new aortic valve regurgitation, aortic root dilation, and right ventricular outflow tract obstruction as children age is a major concern outcome in the future and may mean more late reintervention. neoaorticsinotubular junction reconstruction technique may reduce the incidence of new aortic valve regurgitation and aortic root dilation, and improve the late prognosis of arterial switch operation. Careful follow-up of neo-aortic valve and root function is imperative, especially in patients with aorto-pulmonary diameter mismatch, previous pulmonary artery banding, mild new aortic valve regurgitation at discharge, low surgical weight, and bicuspid native pulmonary valve structures.

Prevalence and Predictors of Readmissions in Patients With Hypertrophic Cardiomyopathy and Atrial Fibrillation/Flutter

Atrial fibrillation/flutter (AF) is the most common dysrhythmia in patients with hypertrophic cardiomyopathy (HCM). Unexplained left ventricular hypertrophy and left ventricular outflow tract obstruction are integral components of HCM pathology which can cause increased left atrial pressure and atrial myopathy contributing to the substrate for AF. We aimed to determine the impact of AF on hospital readmissions in patients with HCM. We conducted a retrospective analysis using the 2015 to 2019 Nationwide Readmission Database to analyze the effect of AF on 30-day readmission and causes of 30-day readmission in patients with HCM. We also determined the hospital, patient, and procedure-specific independent predictors of readmission in patients with HCM and AF. Of 191,235 index HCM hospitalizations, 81,390 (42.6%) had a secondary diagnosis of AF. A total of 16.9% of patients with HCM and AF were readmitted within 30 days as compared with 14% of HCM patients without AF. The presence of AF was independently associated with a higher risk of all-cause 30-day readmission (hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.17 to 1.25, p <0.001). The foremost etiology of 30-day readmission in HCM patients with AF was hypertensive heart and chronic kidney disease with heart failure, whereas the foremost etiology of 30-day readmission in HCM patients without AF was sepsis. Interventions aimed toward AF management (electrical cardioversion: adjusted HR 0.91, 95% CI 0.82 to 1.01. p = 0.074, AF ablation: HR 0.92, 95% CI 0.74 to 1.13, p = 0.409, Watchman procedure: HR 1.50, 95% CI 0.16 to 14.6, p = 0.725) during index admission did not significantly impact the 30-day readmission in HCM patients with AF. Myectomy during index hospitalization (adjusted HR 0.54, 95% CI 0.34 to 0.86, p = 0.010) was most strongly associated with a lower risk of 30-day readmission in HCM patients with AF. In conclusion, in patients hospitalized for HCM, presence of AF was associated with excess risk of 30-day all-cause readmission. Interventions aimed toward HCM management, that is, myectomy rather than interventions aimed toward AF management predicted lower readmission rate in this patient population.

Management of Left Ventricular Intramural Hematoma- an Unusual Complication of Complete Atrioventricular Septal Defect Repair in a Child.

Postoperative survival for complete atrioventricular septal defect (cAVSD) is excellent. Common complications of surgery include valvular stenosis/regurgitation, left ventricular outflow tract obstruction, arrythmias, and residual defects. We report a challenging case of a 7-month old girl with Trisomy 21, preoperative obstructive sleep apnea with severe pulmonary hypertension, who underwent AVSD repair and required veno-arterial extracorporeal membrane oxygenation (V-A ECMO) while unable to come off cardiopulmonary bypass and developed left ventricular intramural hematoma during the course. This case highlights the challenges in management of an unusual complication.

Effectiveness of pulmonary valve-sparing strategy for transatrial-transpulmonary repair of tetralogy of Fallot: a single institution experience.

We report the midterm results of our strategy utilizing transatrial-transpulmonary repair for tetralogy of Fallot at a single institution in a low-middle income country. Medical records were retrospectively reviewed for 532 consecutive patients who underwent definitive repair of tetralogy of Fallot at our institution from 2010 to 2020. The median age and weight of patients in the study patients were 11.6 months (interquartile range, 8.6-17.2 months) and 7.5 kg (interquartile range, 6.8-8.8 kg). The pulmonary valve annulus was preserved (no transannular patch) in 398 patients (75%) and a mini-transannular patch was utilized for 134 patients (25%). The overall survival was 98% at 1 year, and 97% at 10-years follow-up, respectively. Longer postoperative ventilation time was the only risk factor correlated to early death (p = 0.004; Odds Risk, 1.04; 95% confidence intervals, 1.01-1.07). Fourteen patients required pulmonary valve replacement (2.6%, 14/532), four required surgical resection to relieve right ventricular outflow tract obstruction (0.8%, 4/532), and freedom from reoperation of the right ventricular outflow tract was 87% at 10 years. The only risk factor for right ventricular outflow tract reoperation was a postoperative systolic pressure gradient through the right ventricular outflow tract of greater than 50 mmHg (p < 0.001; HR, 47; 95% confidence intervals, 9.1-244). In total, 94.6% (471/489) of the patients were asymptomatic at the latest follow-up without significant arrhythmia. At our institution in an low-middle income country, the transatrial-transpulmonary repair for tetralogy of Fallot has excellent midterm results with few reoperations required. Close long-term follow-up is essential for patients who undergo repair with a mini-transannular patch and may eventually require pulmonary valve replacement.

Exposure to Endocrine-Disrupting Chemicals and Congenital Heart Diseases: The Pooled Results Based on the Current Evidence.

The relationships between maternal exposure to endocrine-disrupting chemicals (EDCs) and congenital heart diseases (CHD) are not elucidated yet. The exposure levels of EDCs are generally estimated based on self-reported questionnaires or occupational exposure evaluations in the literature. Therefore, a study based on epidemiological data from human biospecimens is required to provide stronger evidence between maternal exposure to EDC and CHD. Embase, Pubmed, Scopus, and the Cochrane Library databases were searched for related research which provided risk estimates regarding the relationships between maternal EDC exposure and CHD in human offspring. Baseline characteristics and outcomes of CHD were extracted from each included study. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to calculate the overall estimates of CHD. Subgroup and meta-regression analyses were performed to identify the sources of heterogeneity. Bootstrapping techniques were used in analyses where several studies originated from a similar population. A total of seventeen studies were involved in the meta-analyses. Maternal EDC exposure was significantly related to CHD in offspring (OR 2.15; 95%CI 1.64 to 2.83). EDC exposure was significantly associated with septal defects (OR 2.34; 95%CI 1.77 to 3.10), conotruncal defects (OR 2.54; 95%CI 1.89 to 3.43), right ventricular outflow tract obstruction (OR 2.65; 95%CI 1.73 to 4.07), left ventricular outflow tract obstruction (OR 3.58; 95%CI 2.67 to 4.79), anomalous pulmonary venous return (OR 2.31; 95%CI 1.34 to 4.00), and other heart defects (OR 2.49; 95%CI 1.75 to 3.54). In addition, maternal exposure to heavy metals, which included lead (OR 2.19; 95%CI 1.29 to 3.71), cadmium (OR 1.81; 95%CI 1.28 to 2.56), mercury (OR 2.23; 95%CI 1.13 to 4.44), and manganese (OR 2.65; 95%CI 1.48 to 4.74), increased risks for CHD significantly. In conclusion, based on the latest evidence, maternal EDC exposure may increase CHD risks in human offspring, especially in heavy metal exposure conditions.

Anesthesia management of laparoscopic right colectomy in an older patient with postoperative tetralogy of Fallot with residual anomaly

BackgroundDiversity in hemodynamics of adult congenital heart disease necessitates a case-by-case selection of appropriate surgical and anesthetic options. However, previous case reports regarding the management of laparoscopic surgery in adult patients with congenital heart disease are limited.Case presentationA 72-year-old man who underwent a laparoscopic right colectomy for colon cancer had a residual ventricular septal defect and right ventricular outflow tract obstruction despite post-repair of tetralogy of Fallot. Pulmonary hypertension or right ventricular dysfunction was not observed. The preoperative pulmonary to systemic blood flow ratio (Qp/Qs) was 2.3. After positive pressure ventilation and insufflation, the amount of left-to-right ventricular shunting decreased, and the Qp/Qs approached 1.0, as calculated from pulmonary arterial and systemic arterial blood gas analysis.ConclusionsLaparoscopic surgery might be tolerable in patients with tetralogy of Fallot who have preserved the right ventricular function, left-to-right ventricular shunting, and no high pulmonary vascular resistance.

Individualised surgical treatment strategy for subaortic stenosis.

The clinical data of patients with subaortic stenosis who underwent surgical treatment in our centre in the past 12 years were reviewed. The short-term and long-term clinical outcomes were analyzed, and the long-term outcomes of different surgical methods for subaortic stenosis were compared to determine the optimal surgical treatment strategy for subaortic stenosis. From December 2010 to December 2022, 90 patients undergoing surgical treatment for subaortic stenosis in our hospital were enrolled. There were 55 males and 35 females with a median age of 72 (46,132) months and an average surgical weight of (21.35 ± 15.84) kg. According to the operation method, 90 patients were divided into group A (50 patients with simple subaortic membrane resection) and group B (40 patients with subaortic membrane and muscle resection or modified Konno procedure). There were three early deaths (3.33%). One late death occurred in group B. There was no significant difference in long-term survival rate between the two groups (p = 0.904). The preoperative left ventricular outflow tract pressure gradient in group B was (91.56 ± 36.98) mm Hg, which was higher than that in group A(51.13 ± 36.04)mm Hg(p < 0.001). There was no significant difference in immediate postoperative left ventricular outflow tract pressure gradient between group B [(5.44 ± 8.43) mm Hg] and group A [(7.82 ± 13.44) mm Hg] (p = 0.343). In the long-term follow-up, left ventricular outflow tract pressure gradient in group B was (5.86 ± 9.53) mm Hg, which was not statistically significant compared with group A (8.83 ± 14.52) mm Hg (p = 0.294). Eleven patients with moderate or greater aortic regurgitation (group A/group B: 3/8) underwent simultaneous aortic valvuloplasty. In group B, moderate or greater aortic regurgitation was significantly improved immediately after operation (p = 0.013) and was not significantly aggravated in long-term follow-up (p = 0.083), and there was no significant improvement in group A after operation and long-term follow-up. According to the different anatomical lesions of left ventricular outflow tract, the individualised surgical treatment strategy for patients with subaortic stenosis can achieve good long-term outcomes. The long-term survival rate and freedom from reoperation due to late left ventricular outflow tract obstruction after simple subaortic membrane resection and extended left ventricular outflow tract resection are comparable. For patients with moderate or greater aortic regurgitation before extended left ventricular outflow tract resection, simultaneous aortic valvuloplasty is beneficial to improve postoperative aortic valve function.

Postnatal Cerebral Hemodynamics and Placental Vascular Malperfusion Lesions in Neonates With Congenital Heart Disease

BackgroundNeonates with congenital heart disease (CHD) have smaller brain volume at birth. High rates of placental vascular malperfusion lesions may play a role in disrupted brain development. MethodsThis is a single-center retrospective cohort study of infants born between 2010 and 2019 who were diagnosed with a major cardiac defect requiring surgery in the first year of life. Doppler ultrasound RI of the middle cerebral artery (MCA) and anterior cerebral artery were calculated within the first 72 hours of life. Placentas were evaluated using a standardized approach. ResultsOver the study period, there were 52 patients with hypoplastic left heart syndrome (HLHS), 22 with single-ventricle right ventricular outflow tract obstruction (SV-RVOTO), 75 with a two-ventricle cardiac defect (2V), and 25 with transposition of the great arteries (TGA). MCA Doppler RI were significantly higher for all subgroups of CHD compared with control subjects (0.68 ± 0.11 in control subjects compared with 0.78 ± 0.13 in HLHS, P = 0.03; 0.77 ± 0.10 in SV-RVOTO, P = 0.002; 0.78 ± 0.13 in 2V, P = 0.03; and 0.80 ± 0.14 in TGA; P = 0.001) with the highest average MCA RI in the TGA group. In subgroup analyses, placental fetal vascular malperfusion in the 2V group was associated with higher MCA RI, but this relationship was not present in other subgroups, nor in regards to maternal vascular malperfusion. ConclusionsMajor forms of CHD are associated with significantly higher cerebral artery RI postnatally, but placental vascular malperfusion lesions may not contribute to this hemodynamic adaptation.

Decreased clinical performance in TGA-ASO patients after RVOT interventions; a multicenter European collaboration

BackgroundIn patients with transposition of the great arteries and an arterial switch operation (TGA-ASO) right ventricular outflow tract (RVOT) obstruction is a common complication requiring one or more RVOT interventions. ObjectivesWe aimed to assess cardiopulmonary exercise capacity and right ventricular function in patients stratified for type of RVOT intervention. MethodsTGA-ASO patients (≥16 years) were stratified by type of RVOT intervention. The following outcome parameters were included: predicted (%) peak oxygen uptake (peak VO2), tricuspid annular plane systolic excursion (TAPSE), tricuspid Lateral Annular Systolic Velocity (TV S′), right ventricle (RV)-arterial coupling (defined as TAPSE/RV systolic pressure ratio), and N-terminal proBNP (NT-proBNP). Results447 TGA patients with a mean age of 25.0 (interquartile range (IQR) 21–29) years were included. Patients without previous RVOT intervention (n = 338, 76%) had a significantly higher predicted peak VO2 (78.0 ± 17.4%) compared to patients with single approach catheter-based RVOT intervention (73.7 ± 12.7%), single approach surgical RVOT intervention (73.8 ± 28.1%), and patients with multiple approach RVOT intervention (66.2 ± 14.0%, p = 0.021). RV-arterial coupling was found to be significantly lower in patients with prior catheter-based and/or surgical RVOT intervention compared to patients without any RVOT intervention (p = 0.029). ConclusionsTGA patients after a successful arterial switch repair have a decreased exercise capacity. A considerable amount of TGA patients with either catheter or surgical RVOT intervention perform significantly worse compared to patients without RVOT interventions.

Mitral Regurgitation and Left Ventricular Outflow Tract Obstruction: Confluence of Challenges for Transcatheter Treatment.

The intricate interplay between mitral regurgitation (MR) and left ventricular outflow tract (LVOT) obstruction may result in two clinical scenarios: prosthesis-related LVOT obstruction after mitral valve replacement (TMVR) and systolic anterior motion (SAM)-associated MR. This review provides a comprehensive overview of the pathophysiology, risk assessment, and transcatheter interventions for mitigating the likelihood of LVOT obstruction in patients undergoing TMVR. In addition, it extends its focus to SAM-associated MR, elucidating the different aetiological mechanisms contributing to this phenomenon, beyond hypertrophic cardiomyopathy. Transcatheter treatment options, are explored as potential therapeutic strategies, offering insights into their hemodynamic effectiveness and limitations.

Transcatheter Aortic Valve Embolization Complicated by Inversion and Left Ventricular Outflow Tract Obstruction

Transcatheter Aortic Valve Embolization Complicated by Inversion and Left Ventricular Outflow Tract Obstruction