Outcomes of hypertrophic obstructive cardiomyopathy patients undergoing alcohol septal ablation with a standard 3 mL dose of ethanol: Focus on long-term safety.

OBJECTIVES: The objective of this research was to assess the long-term results of alcohol septal ablation in patients with hypertrophic obstructive cardiomyopathy (HOCM), with all of them receiving a standard 3 mL ethanol dose. BACKGROUND: Generally, ethanol (0.5-3 mL) is infused depending on a septal artery width or interventricular septum (IVS) thickness during alcohol septal ablation. We injected 3 mL of ethanol irrespective of IVS thickness or perforator width in all cases. METHODS: Between 2000 and 2017, 150 HOCM patients (78 males, 72 females) underwent alcohol septal ablation procedures. In all cases we intentionally used the constant dose of ethanol (3 mL). The median of age was 52 (interquartile range: 41-60) years. RESULTS: The median of follow-up was 71 (interquartile range: 36-110) months. Hospital mortality was 0.67% (one patient died of sepsis). Perioperative high-grade atrioventricular blocks required permanent pacemaker implantations-18 (12%). Long-term survival rates were as follows: 95.1% (95% confidence interval [CI]: 92.7-97.5%), 85.8% (95% CI: 83.7-87.0%), and 81.7% (95% CI: 79.7-83.7%) at 5-, 10-, and 15-year follow-up, respectively. One-sample log-rank test revealed no significant differences in 15-year survival rates between the alcohol septal ablation cohort and age- and sex-matched Russian population. CONCLUSIONS: Alcohol septal ablation with the standard (3 mL) ethanol dose is safe and efficient. Survival rates after alcohol septal ablation are comparable with those in age- and sex-matched general Russian population.

Short to medium term outcomes of right ventricular outflow tract stenting as initial palliation for symptomatic infants with complete atrioventricular septal defect with associated tetralogy of Fallot.

OBJECTIVES: To assess the impact of right ventricular outflow tract (RVOT) stenting as the primary palliation in infants with complete atrioventricular septal defect with associated tetralogy of Fallot (cAVSD/TOF). BACKGROUND: Historically, palliation of symptomatic patients with cAVSD/TOF has been achieved through surgical systemic to pulmonary artery shunting. More recently RVOT stenting has evolved as an acceptable alternative in patients with tetralogy of Fallot. METHODS: Retrospective review of all patients with cAVSD/TOF who underwent RVOT stenting as palliation over a 13-year period from two large tertiary referral centers. RESULTS: Twenty-six patients underwent RVOT stenting at a median age of 57 days (interquartile range [IQR] 25.5-106.5). Median weight for stent deployment was 3.7 kg (IQR 2.91-5.5 kg). RVOT stenting improved oxygen saturations from a median of 72% (IQR 70-76%) to 90% (IQR 84-92%), p < .001. There was a significant increase in the median Z-score for both branch pulmonary arteries at median follow-up of 255 days (IQR 60-455). Eight patients required RVOT stent balloon dilatations and 8 patients required re-stenting for progressive desaturation. The median duration between reinterventions was 122 days (IQR 53-294 days). Four patients died during the follow-up period. No deaths resulted from the initial intervention. To date, definitive surgical intervention was achieved in 19 patients (biventricular repair n = 15) at a median age of 369 days (IQR 223-546 days). CONCLUSION: RVOT stenting in cAVSD/TOF is a safe and effective palliative procedure in symptomatic infants, promoting pulmonary artery growth and improving oxygen saturations.

Outcomes of Prosthetic Valved Conduits for Right Ventricular Outflow Tract Reconstruction.

There are limited data regarding the implantation of prosthetic valved conduits for right outflow tract reconstruction in pediatric patients in China. A retrospective review of 128 patients undergoing conduits implantation with a median follow-up of 33.3 months (range, 3.3 months to 10.1 years) was performed between 2009 and 2018. Multivariate Cox regression model was used to analyze the risk factors for mortality, reintervention and endocarditis. Freedom from reintervention and endocarditis were plotted using the Kaplan-Meier curve. Hospital mortality was 7.8%, and the late mortality was 3.1%. Patient survival at 1, 5 and 10 years was 92.2%, 87.1% and 84.3%, respectively. Freedom from reintervention at 1 and 5 years was 94.1% and 60.9%. Small size conduit (p = 0.019) and previous palliation (p < 0.001) were predictive of reintervention. Ten conduits developed endocarditis at a median of 4.8 years after implantation. Freedom from endocarditis at 1, 5 and 10 years was 99.1%, 93.0% and 58.0%, respectively. Diffuse stenosis of the conduit (p = 0.003) was an independent risk factor for late endocarditis. Both bovine jugular venous conduits and bovine pericardial prosthetic conduits are associated with acceptable outcomes. Reintervention remains high in patients who have smaller size conduit and undergo previous palliation. It is plausible that the suboptimal flow may be one of major mechanisms involved in the development of late endocarditis.

Pulmonary artery banding and venous bidirectional cava-pulmonary shunt for two-stage arterial switch procedure in late referral of patients with transposition of the great arteries and intact ventricular septum: midterm results.

OBJECTIVE: Two-stage arterial switch operation and left ventricle retraining are necessary for the patients with left ventricle dysfunction and transposition of great vessels with intact ventricular septum (TGA-IVS) who are referred late. MATERIAL AND METHODS: Forty-seven patients with the diagnosis of TGA-IVS and left ventricle dysfunction who underwent arterial switch operation in our centre between July 2013 and August 2017 were analysed retrospectively. The inclusion criteria for left ventricle retraining were patients older than 2 months of age at presentation, having an echocardiographic left ventricle mass index of less than 35 g/m², and having an echocardiographic "banana-shaped" left ventricle geometric appearance. The patients were divided into two groups: pulmonary artery banding and Blalock Taussig shunt were performed as the initial surgical procedure for later arterial switch operation in Group I (n = 19) and pulmonary artery banding and bidirectional cava-pulmonary shunt in Group 2 (n = 28). RESULTS: The average age was found to be 122.3 ± 45.6 days in Group I and 145.9 ± 37.2 days in Group II. There was no statistically significant difference (p = 0.232 versus p = 0.373) between the average left ventricle mass index of the two groups neither before the first stage nor the second stage (26.6 ± 4.8 g/m² versus 25.0 ± 4.9 g/m² and 70.5 ± 12 g/m² versus 673.8 ± 12.0 g/m², respectively). The average time interval for the left ventricle to retrain was 97.7 ± 42.9 days for Group I and 117.3 ± 40.3 days for Group II, significantly lower in Group I (p = 0.027). The time spent in ICU, length of the period during which inotropic support was required, and the duration of hospital stay were significantly higher in Group I (p<0.001, p < 0.001, and p < 0.00, respectively). CONCLUSION: Pulmonary artery banding and bidirectional cava-pulmonary shunt can be performed as a safe and effective alternative to pulmonary artery banding and arterial Blalock Taussig shunt for patients with TGA-IVS in whom arterial switch operation is needed beyond the neonatal period. This approach involves a shorter hospital stay and fewer post-operative complications.

Incidence, predictors, and midterm clinical outcomes of left ventricular obstruction after transcatheter aortic valve implantation.

OBJECTIVES: We aimed to evaluate the incidence and midterm clinical outcomes of left ventricular obstruction (LVO) after transcatheter aortic valve implantation (TAVI). BACKGROUNDS: LVO is occasionally unmasked following valve replacement for severe aortic stenosis. However, little is known about the prevalence and effects of LVO after TAVI. METHODS: A total of 158 patients who underwent TAVI in our center between October 2013 and November 2015 received echocardiographic evaluations at baseline; before hospital discharge; and at 3, 6, and 12 months after TAVI. LVO was defined as a peak pressure gradient >30 mm Hg. RESULTS: Over 1 year of follow-up after TAVI, 21 patients (13.3%) demonstrated postprocedural LVO. The incidence was highest at 3-months follow-up and decreased at 6 months or later. Of the 21 patients with LVO, 20 (95.2%) demonstrated midventricular obstruction (MVO), whereas only 1 (4.8%) showed obstruction of the outflow tract (LVOT) with systolic anterior motion (SAM) of the mitral leaflet. In a multivariate analysis, the LVOT diameter (odds ratio [OR], 0.45; 95% confidence interval [CI], 0.30-0.67; P < 0.001), transvalvular velocity (OR, 2.44; 95% CI, 1.13-5.26; P = 0.023), and the presence of accelerated intraventricular flow at baseline (OR, 6.13; 95% CI, 1.49-25.2; P = 0.012) were associated with the occurrence of LVO. Postprocedural LVO was not associated with midterm all-cause death or heart failure events. CONCLUSION: In patients who underwent TAVI, MVO occurred more often than LVOT obstruction. However, the occurrence of postprocedural LVO was not associated with worsened clinical outcomes in these patients.

Outcomes of Right Ventricular Outflow Tract Reconstruction for Children with Persistent Truncus Arteriosus: A 10-Year Single-Center Experience.

The purpose of this report is to assess the mid- and long-term outcomes of right ventricular outflow tract (RVOT) reconstruction for children with persistent truncus arteriosus. Between September 2006 and 2016, 105 patients with persistent truncus arteriosus (PTA) received surgical treatment at Shanghai Children's Medical Center. Direct right ventricle-pulmonary artery anastomosis (pulmonary artery pull-down) was performed in 51 patients; a left auricle or pericardial conduit was inserted between the RVOT and pulmonary artery as a connection in 17 patients; heterograft (bovine jugular vein or Gore-tex) conduits and homograft conduits were used in 30 and 7 cases, respectively, to connect the distal pulmonary and right ventricle outflow tract; and pulmonary valve reconstruction was performed in 38 patients using a Gore-tex monocusp. There were six in-hospital deaths and one delayed death 5 months after operation. After a mean follow-up of 55.8 ± 16.5 months (6-113 months), 19 patients underwent reoperation (3 with pulmonary patch enlargement, 14 with conduit replacement and 2 with aortic valve replacement) 10-89 months after the first operation, with 1 hospital death. The actuarial survival rates were 94.2, 93.3 and 93.3% at 1, 5 and 10 years, respectively. Freedom from reoperation was 98.0, 87.8 and 82.7% at 1, 5 and 10 years, respectively. The follow-up variables included echocardiography, chest radiography, cardiac CT and cardiac function. At the last examination, most of the patients exhibited an improvement of New York Heart Association functional class from III or IV preoperatively to I or II at follow-up. Surgical treatment for PTA has an acceptable survival rate and satisfactory outcomes. Most patients exhibited an improvement in cardiac function during follow-up. Aortic arch deformity, truncal valvular regurgitation and long cardiopulmonary bypass time were regarded as risk factors for hospital mortality. Autologous tissue has a lower reoperation rate and better growth potential than extracardiac conduits. A monocusp valve effectively reduces pulmonary regurgitation in the early postoperative stage.

Value of latent outflow obstruction to predict clinical course of patients with hypertrophic cardiomyopathy.

Objective The frequency, significance and prognostic value of left ventricle obstruction (LVO) induced with provocation (latent LVO) is controversial for hypertrophic cardiomyopathy (HC) patients. This study was designed to assess the value of latent LVO in predicting the clinical course in 101 patients with HC. Methods and results Patients were followed for a mean of 82 ± 48 months (range 2 to 148 months) for clinical end points defined as a composite of cardiovascular death resuscitated cardiac arrest, appropriate defibrillator shock or hospitalization due to worsening of heart failure symptoms. Presence of LVO (hazard ratio 3.63; 95% confidence interval, 1.85 to 7.12; P = 0.0001) and log NT-proBNP levels (hazard ratio, 1.40; 95% confidence interval, 1.14 to 1.72; P = 0.001) were the independent variables associated with an increased risk of experiencing clinical end points. HC patients with latent LVO have a trend toward decreased survival when compared with HC patients without LVO (log rank P = 0.027), but better survival than patients with resting LVO (log rank P = 0.007). HC patients with NT-proBNP levels <1,000 pg/ml had also better survival. LVO and NT-proBNP levels are the major determinants of clinical end points in patients with HC. Conclusions Evaluation of patients without resting LVO to demonstrate latent obstruction is of critical importance in respect of outcome and selection of patients for septal reduction therapies, so routine provocative testing with physiological exercise and measurement of NT-proBNP is recommended in this patient population for risk stratification.

A meta analysis of current status of alcohol septal ablation and surgical myectomy for obstructive hypertrophic cardiomyopathy.

OBJECTIVE: Our objective was to perform an updated systematic review to compare the efficacy and short- and long-term mortality of surgical myectomy (SM) and alcohol septal ablation (ASA) by including most recent and largest cohort studies published in last few years. BACKGROUND: SM and ASA are the two invasive strategies used to relieve left ventricular outflow tract obstruction (LVOTO) in patients with drug refractory symptomatic hypertrophic cardiomyopathy (HCM). In the absence of a randomized trial, we tried to compare the pros and cons of the two procedures using a systematic review and meta-analysis. METHOD: A comprehensive search of three major databases was performed. We included original research studies comparing data on ASA and SM. Of 1,143 citations, 10 studies were included in the analysis. RESULTS: A total of 805 patients underwent ASA and 1,019 underwent SM. Patients undergoing SM were younger (MD 6.3, P = 0.0001) and had higher reduction in the LVOT gradient (MD -9.56, P = 0.05). However, there was similar resolution of class III and IV symptoms between the two groups (P = 0.56). There was no difference in sudden cardiac death (SCD) (P = 0.93), short-term (P = 0.36), long-term all cause (P = 0.27), and long-term cardiac mortality (P = 0.58). Patients undergoing ASA had higher incidence of post procedure device implantation (OR 3.09, P < 0.00001). CONCLUSION: No significant difference in symptom relief was noted between the two approaches. ASA was as safe a myectomy with regards to SCD, short-term, and long-term mortality. © 2015 Wiley Periodicals, Inc.

Summary of Clinical Experience of Modified Double Root Translocation in the Management of Complete Transposition of Great Arteries With Left Ventricular Outflow Tract Obstruction.

To summarize the therapeutic effects of modified double root translocation (MDRT) in the management of congenital heart disease-transposition of great arteries (TGA) with ventricular septum defect (VSD) and left ventricular outflow tract obstruction (LVOTO). From May 2013 to March 2015, we treated 6 patients (4 males, 2 females, aged from 1 year and 8 months old to 5 years old) with complete transposition of great arteries with left ventricular outflow tract obstruction, SaO2 54 ± 7.3%; the outflow velocity of the left ventricular or pulmonary valve measured by Doppler was 4.46 ± 0.15 m/s, and the Nakata index was 217 ± 32 cm(2)/m(2). We carried out a double root translocation operation on these 6 patients.One patient developed low cardiac output syndrome 4 hours after the operation. Extracorporeal membrane oxygenation (ECMO) was performed, but the patient died of multiple organ failure. The other 5 patients all recovered and were discharged from the hospital. During the 3-month to 2-year follow-up period, these 5 patients all demonstrated NYHA Class I or NYHA Class II LVEF (65 ± 2.7) %; 4 had mild pulmonary regurgitation, 1 moderate pulmonary regurgitation; 3 no aortic regurgitation, and 2 micro aortic regurgitation, SaO2 99 ± 0.4%.Modified double root translocation is an effective treatment method in the management of complete transposition of great arteries with left ventricular outflow tract obstruction.

Transcatheter balloon dilation for recurrent right ventricular outflow tract obstruction following valve-sparing repair of tetralogy of Fallot.

BACKGROUND: Valve-sparing repair in patients with tetralogy of Fallot (TOF) carries the risk of residual or recurrent right ventricular outflow tract (RVOT) obstruction, which is often treated with transcatheter balloon dilation (BD). The outcomes and associated complications of BD of the RVOT in this scenario remain unknown. METHODS: Retrospective review of the records of the Department of Cardiology at Boston Children's Hospital from 2000 to 2013 was performed. RESULTS: 34 patients had initial valve-sparing repair of tetralogy of Fallot followed by BD of the RVOT during the study period. Following BD, the RVOT gradient decreased from a median of 43 mm Hg (range 13 to 79 mm Hg) to 28 mm Hg (range 0 to 73 mm Hg) (P < 0.001). Freedom from reintervention was 64% at 1 year and 46% at 3 years. Trivial to mild PR pre-BD was present in 56% (n = 19) of patients and decreased to 37% (n = 11) post-BD. Exclusively valvar obstruction was associated with a longer freedom from reintervention (P = 0.05), while a ratio of RV pressure to aortic systolic pressure pre-BD of >1 and a final RVOT gradient of ≥40 post-BD were associated with shorter freedom from reintervention (P < 0.001). CONCLUSION: BD in patients with recurrent RVOT obstruction following valve-sparing repair of TOF acutely reduces the RVOT gradient, but commonly results in increased PR and is associated with a high reintervention rate. Patients with stenosis solely at the level of the valve had a better response to this type of intervention.

Clinical impact of left ventricular outflow tract obstruction in takotsubo cardiomyopathy.

BACKGROUND: A hyperdynamic state of the basal left ventricle sometimes results in obstruction of the left ventricular outflow tract (LVOT). However, the prevalence, clinical presentation, and prognostic effect of LVOT obstruction in takotsubo cardiomyopathy (TC) have not been fully evaluated. METHODS AND RESULTS: Among 933 consecutive patients who underwent emergency coronary angiography for suspected acute coronary syndrome, 35 patients (3.8%) were diagnosed as TC. The cumulative 3-year incidence of all-cause death, cardiac death, hospitalization for congestive heart failure (CHF), and recurrent TC was 24.2%, 0.0%, 6.5%, and 12.2%, respectively. Among 27 patients with information of a LVOT pressure gradient, LVOT obstruction was present in 9 (33%). The prevalence of moderate to severe mitral regurgitation (67% vs. 11%, P=0.003), CHF (78% vs. 28%, P=0.02), and hypotension (56% vs. 5.6%, P=0.008) was significantly higher in patients with LVOT obstruction than in those without. Nevertheless, the cumulative 3-year incidence of all-cause death was not significantly different between the 2 groups (49.2% vs. 23.0%, P=0.22) with no cardiac deaths in either group. Hospitalization for CHF and recurrent TC were significantly more frequent in patients with LVOT obstruction (25.0% vs. 0.0%, P=0.04, and 25.0% vs. 6.7%, P=0.02). CONCLUSIONS: In 35 consecutive patients with TC, those with significant LVOT obstruction (33%) had a more serious clinical presentation such as CHF and hypotension, but had similar 3-year mortality rate as compared with those without.

Outcome of Standard and Bicuspidalized Cryopreserved Homografts for Primary Right Ventricular Outflow Tract Reconstruction.

BACKGROUND AND AIM OF THE STUDY: The study aim was to analyze the safety and longevity of cryopreserved homografts used for primary right ventricular outflow tract reconstruction (RVOTR), and to compare the outcome using either standard or bicuspidalized allografts. METHODS: Between February 2000 and September 2014, a total of 53 patients underwent primary RVOTR using either a standard (n = 40) or a bicuspidalized (n = 13) cryopreserved homograft. The median age at surgery was 15.5 months (range: 1-419.06 months), and bodyweight was 8.5 kg (range: 4.1-71 kg). The median standard homograft size was 17.5 mm (range: 10-25 mm), while the median bicuspidalized homograft size was 16 mm (range: 14-22 mm). Follow up was complete in 91.4% of patients, with a median duration of 30.11 months (range: 0.26-161.26 months). Data analysis included primary diagnosis, type of surgery, age at surgery, size of conduit, need for reintervention, and survival. Predetermined primary outcomes were represented by survival and freedom from conduit reintervention. RESULTS: Two patients with standard cryopreserved homograft died. during the early postoperative period (3.7%). No deaths were conduit-related. The five-year survival rate and ten-year freedom from reintervention were 91% (range: 74.7-97.2%) and 53.6% (range: 97-33.2%), respectively. RV-PA conduit replacement was performed in 14 patients (26.4%) at a median interval of 44.5 months (range: 14.93-162.46 months). Among these patients, four children (30.7%) received bicuspidalized homografts, and 10 (25%) received standard homografts. Causes of reintervention were conduit stenosis in six cases (43%), severe homograft valve regurgitation in two (14.2%), conduit stenosis and homograft valve regurgitation in two (14.2%), and stenosis of distal anastomosis involving pulmonary bifurcation in four (28.6%). Univariate analyses showed a longer freedom from reintervention for bicuspidalized compared to standard homograft (p = 0.03). CONCLUSION: The results obtained suggested that bicuspidalized homograft performance compares well with that of standard allografts in terms of freedom from reintervention. Bicuspidalized homograft use is strongly indicated for primary RVOTR in small children, when a standard homograft of appropriate size is not available.

Physiological and phenotypic characteristics of late survivors of tetralogy of fallot repair who are free from pulmonary valve replacement.

BACKGROUND: Pulmonary valve replacement (PVR) after repair of tetralogy of Fallot is commonly required and is burdensome. Detailed anatomic and physiologic characteristics of survivors free from late PVR and with good exercise capacity are not well described in a literature focusing on the indications for PVR. METHODS AND RESULTS: Survival and freedom from PVR were tracked in 1085 consecutive patients receiving standard tetralogy of Fallot repair in a single institution from 1964 to 2009. Of 152 total deaths, 100 occurred within the first postoperative year. Surviving patients between 10 and 50 years of age had an annual risk of death of 4 (confidence limit, 2.8-5.4) times that of normal contemporaries. To date, 189 patients have undergone secondary PVR at mean age of 20±13 years (36% of those alive at 40 years of age). A random sample of 50 survivors (age, 4-57 years) free from PVR underwent cardiovascular magnetic resonance, echocardiography, and exercise testing. These patients had mildly dilated right ventricles (right ventricular end-diastolic volume=101±26 mL/m(2)) with good systolic function (right ventricular ejection fraction=59±7%). Most had exercise capacity within normal range (z peak o2=-0.91±1.3; z e/ co2=0.20±1.5). In patients >35 years of age with normal exercise capacity, there was mild residual right ventricular outflow tract obstruction (mean gradient, 24±13 mm Hg), pulmonary annulus diameters <0.5z, and unobstructed branch pulmonary arteries. CONCLUSIONS: An important proportion of patients require PVR late after tetralogy of Fallot repair. Patients surviving to 35 years of age without PVR and with a normal exercise capacity may have had a definitive primary repair; their right ventricular outflow tracts are characterized by mild residual obstruction and pulmonary annulus diameter <0.5z.

Predictors of long-term outcomes in symptomatic hypertrophic obstructive cardiomyopathy patients undergoing surgical relief of left ventricular outflow tract obstruction.

BACKGROUND: We report the predictors of long-term outcomes of symptomatic hypertrophic cardiomyopathy patients undergoing surgical relief of left ventricular outflow tract obstruction. METHODS AND RESULTS: We studied 699 consecutive patients who have hypertrophic cardiomyopathy with severe symptomatic left ventricular outflow tract obstruction (47±11 years, 63% male) intractable to maximal medical therapy, who were referred to a tertiary hospital between January 1997 and December 2007 for the surgical relief of left ventricular outflow tract obstruction. We excluded patients <18 years of age, those with an ejection fraction <50%, those with hypertensive heart disease of the elderly, and those with more than mild aortic or mitral stenosis. Clinical, echocardiographic, and Holter data were recorded. A composite end point of death, appropriate internal cardioverter defibrillator discharges, resuscitated from sudden death, documented stroke, and admission for congestive heart failure was recorded. During a mean follow-up of 6.2±3 years, 86 patients (12%) met the composite end point with 30-day, 1-year, and 2-year event rates of 0.7%, 2.8%, and 4.7%, respectively. The hard event rate (death, defibrillator discharge, and resuscitated from sudden death) at 30 days, 1 year, and 2 years was 0%, 1.5%, and 3%, respectively. Stepwise multivariable analysis identified residual postoperative atrial fibrillation (hazard ratio, 2.12; confidence interval, 1.37-3.34; P=0.001) and increasing age (hazard ratio, 1.49; confidence interval, 1.22-1.82; P=0.001) as independent predictors of long-term composite outcomes. CONCLUSIONS: Symptomatic adult hypertrophic cardiomyopathy patients undergoing surgery for the relief of left ventricular outflow tract obstruction have low event rates during long-term follow-up; worse outcomes are predicted by increasing age and the presence of residual atrial fibrillation during follow-up.

Prevalence, associated factors and management implications of left ventricular outflow tract obstruction in takotsubo cardiomyopathy: a two-year, two-center experience.

BACKGROUND: Some patients with Takotsubo cardiomyopathy (TTC) develop cardiogenic shock due to left ventricular outflow tract (LVOT) obstruction - there is, however, a paucity of data regarding this condition. METHODS: Prevalence, associated factors and management implications of LVOT obstruction in TTC was explored, based on two-year data from two Belgian heart centres. RESULTS: A total of 32 patients with TTC were identified out of 3,272 patients presenting with troponin-positive acute coronary syndrome. In six patients diagnosed with TTC (19%), a significant LVOT obstruction was detected by transthoracic echocardiography. Patients with LVOT obstruction were older and had more often septal bulging, and presented more frequently in cardiogenic shock as compared to those without LVOT obstruction (P < 0.05). Moreover, all patients with LVOT obstruction showed systolic anterior motion (SAM) of the anterior mitral valve leaflet, which was associated with a higher grade of mitral regurgitation (2.2±0.7 vs. 1.0±0.6, P<0.001). Adequate therapeutic management including fluid resuscitation, cessation of inotropic therapy, intravenous ß-blocker, and the use of intra-aortic balloon pump resulted in non-inferior survival in TTC patients with LVOT obstruction as compared to those without LVOT obstruction. CONCLUSIONS: TTC is complicated by LVOT obstruction in approximately 20% of cases. Older age, septal bulging, SAM-induced mitral regurgitation and hemodynamic instability are associated with this condition. Timely and accurate diagnosis of LVOT obstruction by echocardiography is key to successful management of these TTC patients with LVOT obstruction and results in a non-inferior outcome as compared to those patients without LVOT obstruction.

Clinical presentation and surgical outcomes in patients with Shone's complex: a systematic review.

OBJECTIVE: Shone's complex comprises of a combination of congenital cardiac anomalies causing obstructions in the left ventricle's inflow and outflow tracts. This systematic review aims to evaluate the clinical features and surgical outcomes of Shone's complex. METHODS: An electronic literature search of PubMed and Scopus was performed to identify relevant studies related to the presentation, management, and outcomes of Shone's complex. Two reviewers independently performed selection. Data on study characteristics, participant demographics, interventions, outcomes, and follow-up durations were extracted and analyzed. RESULTS: A total of 691 papers were identified, with 18 studies included in the final analysis. The majority of the studies (n = 12) focused on the pediatric age group. The most common clinical presentations were coarctation of the aorta (n = 17) and mitral stenosis (n = 12). Surgical interventions often involved staged approaches, prioritizing outflow before inflow obstructions. Mitral valve repair was preferred over replacement due to better long-term outcomes (n = 8). Biventricular repair was recommended due to improved postoperative outcomes, but often needed reoperations. Reoperations were common, primarily due to recurrent coarctation (n = 10), subaortic stenosis (n = 8), and mitral valve dysfunction (n = 7). Pulmonary hypertension (n = 10) and arrhythmias (n = 11) were significant complications. Most patients were in modified Ross/NYHA functional class 1 on follow-up. Mortality rates ranged from 4 to 28%, with better outcomes associated with early and strategic surgical interventions. CONCLUSION: Early diagnosis and biventricular repair were associated with better outcomes while transplantation was often an eventuality. Standardized diagnostic criteria, long-term follow-up, and consensus guidelines are needed to improve the management of this congenital heart disease.

5-Year Outcomes of Anterior Mitral Leaflet Laceration to Prevent Outflow Obstruction.

BACKGROUND: Left ventricular outflow tract (LVOT) obstruction is a common, often fatal complication of transcatheter mitral valve replacement (TMVR). Laceration of the anterior mitral leaflet to prevent outflow obstruction (LAMPOON) was safe and effective at preventing LVOT obstruction at 30 days in the National Heart, Lung, and Blood Institute LAMPOON trial. OBJECTIVES: The authors report the 5-year outcomes of intentional anterior mitral leaflet laceration before SAPIEN 3 TMVR, in patients at risk of LVOT obstruction. METHODS: The National Heart, Lung, and Blood Institute LAMPOON trial was a prospective, multicenter, single-arm safety and feasibility study of LAMPOON and transseptal SAPIEN 3 TMVR in annuloplasty rings (valve-in-ring) or native mitral annular calcification (MAC) (valve-in-MAC). All subjects had high predicted risk for LVOT obstruction. Subjects were not excluded for excessive frailty or comorbidity. The primary endpoints were technical success and safety at 30 days. Secondary clinical and echocardiographic endpoints were assessed at 1 year and clinical follow-up at 5 years. RESULTS: Thirty subjects were enrolled between June 2017 and June 2018, equally between the valve-in-MAC and valve-in-ring arms. At 30 days, LAMPOON was successful in all 30 subjects, with no strokes, 1 (3%) death, and 1 (3%) moderate LVOT obstruction. Eighteen (65%) survived to 1 year, and 7 (25%) survived to 5 years. Six (20%) were hospitalized for heart failure in the first year. From baseline to 1 year, there was a 24-point improvement in Kansas City Cardiomyopathy Questionnaire score and a 60-m improvement in 6-minute walk distance. There was no significant change in N-terminal pro-brain natriuretic peptide. At 1 year, LVOT gradients remained low. CONCLUSIONS: LAMPOON enabled TMVR despite the risk for LVOT obstruction. There were no long-term complications associated with LAMPOON. The selection of inoperable patients limited assessment of long-term survival following TMVR. (NHLBI DIR LAMPOON Study: Intentional Laceration of the Anterior Mitral Leaflet to Prevent Left Ventricular Outflow Tract Obstruction During Transcatheter Mitral Valve Implantation; NCT03015194).

Bare metal stenting for obstructed small diameter homograft conduits in the right ventricular outflow tract.

OBJECTIVE: Our aim was to assess acute hemodynamic changes with stent insertion, outcomes, and factors associated with increased longevity of stented small diameter homograft conduits. BACKGROUND: Right ventricle-to-pulmonary artery (RV-PA) homograft conduits are commonly used to palliate RV outflow tract obstruction. Bare metal stenting (BMS) and transcatheter pulmonary valve implantation have been shown to relieve obstructed larger diameter conduits and may delay surgical conduit reintervention. Less is known about BMS of small conduits. METHODS AND RESULTS: From 1992 to 2009, BMS was performed to relieve obstruction in 106 homograft conduits that were ≤12 mm at implant. The peak RV-PA gradient fell from 54.3 ± 17.4 mm Hg at baseline to 46.1 ± 15.2 mm Hg after balloon dilation alone and to 25.1 ± 11.4 mm Hg with stenting (all P < 0.001). Higher pre-BMS gradient and RV pressure were the only factors associated with higher post-BMS RV-PA gradient (≥30 mm Hg; both P < 0.001). There were no procedural deaths, two patients required surgical removal of embolized stents. At a median follow-up of 1.6 years, 83 conduits were replaced; freedom from conduit reoperation after BMS was 66% ± 5% at 1 year and 28% ± 5% at 3 years. Factors associated with shorter freedom from reoperation included implanted conduit diameter <10 mm (P = 0.009), higher post-stent RV-PA gradient (P = 0.026), and higher post-stent RV pressure (P < 0.01); only post-stent RV pressure remained significant on multivariable analysis (P < 0.001). CONCLUSION: BMS was acutely effective for the treatment of obstructed small diameter homograft conduits, with low morbidity. Prolongation of small diameter homograft conduit longevity with BMS may be useful in the lifetime management of conduit dysfunction in this patient population.

Clinical characteristics and natural history of hypertrophic cardiomyopathy with midventricular obstruction.

BACKGROUND: The prevalence, clinical characteristics and natural history of patients with hypertrophic cardiomyopathy (HCM) and midventricular obstruction (MVO) have not been adequately studied. METHODS AND RESULTS: A single-center cohort consisting of 423 patients (mean age, 49.3±17.2 years; 66.2% male) was thoroughly followed up for a median of 84 months (7 years; range, 6-480 months). MVO, characterized by the echocardiographic appearance of midventricular muscular apposition with a simultaneous mid-cavitary gradient ≥30mmHg, was identified in 34 patients (8%). Patients with MVO tended to be more symptomatic during their initial evaluation (>90% presented with NYHA class ≥II) compared to the rest of the HCM cohort. Apical aneurysm formation was identified in more than one-fourth of patients with MVO (26.5%), being a characteristic of the group. On multivariate Cox regression hazard analysis, presence of MVO strongly predicted progression to end-stage (burnt out) HCM and related heart failure (HF) deaths (hazard ratio, [HR], 2.62; 95% confidence interval [CI]: 1.2-8.8; P=0.047), as well as sudden death and associated lethal arrhythmic events (HR, 3.3; 95% CI: 1.26-8.85; P=0.016). CONCLUSIONS: MVO is a distinct phenotype of HCM associated with unfavorable prognosis in terms of end-stage HCM, sudden death and lethal arrhythmic events. The high adverse outcome rate necessitates early recognition of MVO and appropriate therapeutic interventions.

Reduced fractional shortening of right ventricular outflow tract is associated with adverse outcomes in patients with left ventricular dysfunction.

BACKGROUND: Recent studies suggest the significance of right ventricular (RV) function in the outcome in patients with left ventricular dysfunction (LVSD); however, global assessment of RV remains to be determined by echocardiogram because of its complex geometry. This study aimed to validate RV outflow tract fractional shortening (RVOT-FS) in the evaluation of RV function and its prognostic value in patients with LVSD. METHODS: This study included eighty-one patients (62 ± 17 years, mean ± SD, male 79%) with reduced LV ejection fraction (LVEF) (≤40%). Two-dimensional echocardiogram of the parasternal short axis view was obtained at the level of the aortic root, and RVOT-FS was calculated as the ratio of end-diastole minus end-systole dimension to end-diastole dimension. RESULTS: RVOT-FS ranged from 0.04 to 0.8 (0.3 ± 0.2, mean ± SD), and correlated with LVEF (r = 0.33, p = 0.0028), RV fractional area change (r = 0.37, p = 0.0008) and brain natriuretic peptide level (r = -0.38, p = 0.0005). In Cox multivariate regression analysis, RVOT-FS [hazard ratio (HR) 0.028, 95% confidence interval (CI): 0.002-0.397]; p = 0.008] and New York Heart Association functional class III-IV [HR 2.233, 95% CI: 1.048-4.761]; p = 0.037] were independent factors to predict the events. During a median follow-up period of 319 days (1 to 1862 days), patients with RVOT-FS ≥ 0.2 showed a higher event-free rate than those < 0.2 by Kaplan-Meier analysis (log-rank test, p = 0.0016). CONCLUSIONS: Our data suggest that RVOT-FS is a simple parameter reflecting the severity of both ventricular function in patients with LVSD. In addition, RVOT-FS might be useful to predict adverse outcomes in such a patient population.