Hypertrophic Cardiomyopathy: Preadolescence, Mitral Valve Disease, and Midventricular Obstruction.

Septal myectomy is indicated in patients with obstructive hypertrophic cardiomyopathy (HCM) who have persistent symptoms despite medical therapy, intolerance of medication side effects, or severe resting or provocable gradients. Septal myectomy at high volume centers is safe, with low operative mortality (1%) and low rates of complications such as complete heart block or ventricular septal defect (3% and 0.5%, respectively). Additionally, improved survival following myectomy has been observed when compared to patients with obstructive HCM managed medically or those with nonobstructive HCM. As a longstanding, quaternary referral center for septal myectomy, our institution has built significant experience and expertise in the surgical and medical management of HCM, including atypical HCM, defined as preadolescent patients, those with mitral valve disease, and those with isolated midventricular obstruction. The most important factor of septal myectomy in achieving complete resolution of obstruction and avoiding recurrence is the apical extent of the myectomy trough, which must extend to the septum opposite the papillary muscles. If this cannot be fully achieved via a transaortic exposure, especially in preadolescents and patients with midventricular obstruction, then a transapical approach may be needed. Mitral valve repair is rarely necessary as SAM-mediated MR resolves with adequate myectomy alone, but mitral repair is performed in cases of intrinsic valvular disease. In this manuscript we provide a summary of current operative techniques and outcomes data from our institution on the management of these various categories of HCM.

Anomalous Aortic Origin of a Coronary Artery.

BACKGROUND: Although anomalous aortic origin of a coronary artery (AAOCA) is associated with risk of sudden cardiac arrest (SCA), there is a spectrum of disease, with the appropriate management for many remaining unclear. Increasing data warrant review for an updated perspective on management. METHODS: A panel of congenital cardiac surgeons, cardiologists, and imaging practitioners reviewed the current literature related to AAOCA and its management. Survey of relevant publications from 2010 to the present in PubMed was performed. RESULTS: The prevalence of AAOCA is 0.4% to 0.8%. Anomalous left coronary artery is 3 to 8 times less common than anomalous right coronary, but carries a much higher risk of SCA. Nevertheless, anomalous right coronary is not completely benign; 10% demonstrate ischemia, and it remains an important cause of SCA. Decision-making regarding which patients should be recommended for surgical intervention includes determining anatomic features associated with ischemia, evidence of ischemia on provocative testing, and concerning cardiovascular symptoms. Ischemia testing continues to prove challenging with low sensitivity and specificity, but the utility of new modalities is an active area of research. Surgical interventions focus on creating an unobstructed path for blood flow and choosing the appropriate surgical technique given the anatomy to accomplish this. Nontrivial morbidity has been reported with surgery, including new-onset ischemia. CONCLUSIONS: A proportion of patients with AAOCA demonstrate features and ischemia that warrant surgical intervention. Continued work remains to improve the ability to detect inducible ischemia, to risk stratify these patients, and to provide guidance in terms of which patients warrant surgical intervention.

Valve-Sparing Aortic Root Replacement State-of-the-Art Review, Part I: Anatomy and Physiology.

Aortic valve disease is common, and valve-preserving operations are preferred whenever possible. Valve-sparing aortic root replacement has become an important tool for managing aortic root pathology in children and adults. The learning curve for this operation is challenging, but with increasing experience and technical modifications, early and late outcomes continue to improve. Durable long-term results vary based on the underlying anatomy, pathology, and patient selection, as well as surgeon expertise. The first installment of this Valve-Sparing Aortic Root Replacement State-of-the-Art Review article addresses patient anatomy and physiology as it relates to candidacy for VSRR.

Valve-Sparing Aortic Root Replacement State of the Art Review Part II: Surgical Techniques.

Aortic valve disease is common and valve-preserving operations are preferred whenever possible. Valve-sparing aortic root replacement (VSRR) has become an important tool for managing aortic root pathology in children and adults. The learning curve for this operation is challenging but with increasing experience and technical modifications, early and late outcomes continue to improve. Durable long term results vary based on underlying anatomy, pathology, and patient selection, and surgeon expertise. The purpose of Part II of this VSRR State of the Art Review article is to provide technical pearls related to VSRR.

Utility of routine follow-up defibrillation safety margin testing in young patients with epicardial implantable cardioverter-defibrillators.

BACKGROUND: Routine defibrillation threshold testing (DFT) of transvenous implantable defibrillators (ICDs) has largely been in decline. In patients with non-transvenous ICDs that utilize subcutaneous and pleural ICD leads, serial DFT testing can detect a significant number of failures. Data about the utility of follow-up defibrillation safety margin testing (DSM) testing in pediatric patients and young adults with an epicardial ICD are lacking. METHODS: Patients aged < 25 years old who underwent epicardial ICD placement at Mayo Clinic from 2014 to 2023 with at least one follow-up DSM test were included. The patients were divided into a "routine" (R) and "clinically indicated" (CI) group based on the index of clinical concern. Inadequate DSM was defined as unsuccessful defibrillation at an output of less than 10 J below the maximum output of the device. The purpose of this study was to assess the utility of follow-up DSM testing. RESULTS: An epicardial ICD system was placed in 122 patients. A total of 26 patients met inclusion criteria and underwent a total of 47 DSM follow up tests. Inadequate DSM occurred in 1/33 (3%) in the R group and 2/14 (14%) DSM tests in the CI group. The median follow-up period was 54 and 36 months for the R and CI group, respectively. CONCLUSIONS: Our data suggest that epicardial ICDs are reliable and routine follow-up DSM testing may not be necessary for all patients. DSM testing should be performed in individuals with epicardial ICD systems when there is clinical concern about lead or coil performance.

Outcomes of Surgical Repair of Aberrant Subclavian Arteries in Adults.

BACKGROUND: Symptoms, imaging characteristics, and early and midterm surgical outcomes for aberrant subclavian arteries (ASCA) are not well defined in the adult population. METHODS: A single-institution retrospective review was conducted of adults undergoing surgical repair of ASCA and descending aorta origin/Kommerell diverticulum (KD) from January 1, 2002, to December 31, 2021. Symptom improvement and differences in imaging characteristics between anatomic groups and the number of symptoms were assessed. RESULTS: Mean age was 46 ± 17 years. There were 23 of 37 left aortic arches with right ASCA (62%) and 14 of 37 right aortic arches with left ASCA (38%). Of these, 31 of 37 (84%) were symptomatic, and 19 of 37 (51%) had KD size/growth meeting criteria for surgical repair. KD aortic origin diameter was larger in more symptomatic patients: 20.60 mm (interquartile range [IQR], 16.42-30.68 mm) in patients with ≥3 symptoms vs 22.05 mm (IQR, 17.52-24.21 mm) for 2 symptoms vs 13.72 mm (IQR, 12.70-15.95 mm) for 1 symptom (P = .018). Aortic replacement was required in 22 of 37 (59%). There were no early deaths. Complications occurred in 11 of 37 (30%): vocal cord dysfunction (4 of 37 [11%]), chylothorax (3 of 37 [8%]), Horner syndrome (2 of 37 [5%]), spinal deficit (2 of 37 [5%]), stroke (1 of 37 [3%]), and temporary dialysis requirement (1 of 37 [3%]). Over a median follow-up of 2.3 years (IQR, 0.8-3.9 years), there was 1 endovascular reintervention and no reoperations. Dysphagia and shortness of breath resolved in 92% and 89%, respectively, whereas gastroesophageal reflux persisted in 47%. CONCLUSIONS: The KD aortic origin diameter correlates with the number of symptoms, and surgical repair of ASCA and descending aorta origin/KD effectively relieves symptoms, with low rates of reintervention. Given the operative complexity, surgical repair should be performed in patients meeting size criteria or with significant dysphagia or shortness of breath symptoms.

Surgical Considerations for the Mitral Valve in Congenitally Corrected Transposition.

BACKGROUND: Systemic atrioventricular valve (morphologic tricuspid valve [TV]) regurgitation has been implicated in the development of systemic ventricular failure in congenitally corrected transposition of the great arteries (ccTGA), leading to timely referral for valve replacement. However, the surgical management of subpulmonary atrioventricular valve (morphologic mitral valve [MV]) regurgitation and outcomes has not been well studied. METHODS: Of 108 ccTGA patients undergoing atrioventricular valve surgery from 1979 to 2022, 22 patients (20%) underwent MV surgery. Demographics, etiology of valve regurgitation, operative details, and outcomes of these 22 patients were retrospectively reviewed. Follow-up at 1, 5, and 10 years was available for 18 (82%), 13 (59%), and 11 patients (50%), respectively. RESULTS: Median age was 37 years (interquartile range, 29-57 years). Intrinsic MV pathology was present in 18 individuals (82%). Operations included repair in 16 patients (73%), replacement in 6 (27%), and concomitant replacement of TV in 16 (73%). There was 1 perioperative death (5%) in a patient undergoing an emergent operation for severe acute-on-chronic heart failure due to worsening TV regurgitation. During a median follow-up of 12 years (interquartile range, 2-19 years), 7 patients (32%) died. Among the 16 patients who underwent repair, recurrent moderate or greater regurgitation was seen in 15%, 29%, and 43% of repairs in patients with annular, leaflet, and lead-induced regurgitation, respectively. CONCLUSIONS: Concomitant TV and MV disease occur much less frequently than isolated TV disease in ccTGA. Intrinsic MV disease is most commonly observed but appears less amenable to successful repair compared with mitral repair in the systemic position and suggests MV replacement may be preferred in ccTGA patients.

National In-Hospital Outcomes of Mechanical Mitral Valve Replacement in the Pediatric Population.

Background: National data about the outcomes of children undergoing mechanical mitral valve replacement (m-MVR) are scarce. Methods: A retrospective review of hospitalizations from the Kids' Inpatient Database was performed for patients ≤18 years of age in the United States. A total of 500 patients underwent m-MVR in 2009, 2012, 2016, and 2019. Patients with single ventricle physiology were excluded (n = 13). These patients were categorized into three groups according to age: neonates (<1 month, n = 20), infants (1-12 months, n = 76 patients), and children (1-18 years, n = 404). Outcomes were compared between the three groups. Results: The proportion of m-MVR involving children undergoing MV procedures (repair and replacement) has increased from 17.3% in 2009 to 30.8% in 2019 (Ptrend < .01). History of cardiac surgery was present in 256 patients (51.2%). Concomitant procedures were performed in 119 patients (23.8%). Intra- or postoperative extracorporeal membrane oxygenation was required in 19 patients (3.8%). The overall in-hospital mortality was 4.8% and was significantly higher in neonates and infants compared with older children (10% vs 11.8% vs 3.2%, P = .003). The length of hospital stay was longer in the neonatal group (median, 57 days, interquartile range, [24.8-90] vs 29.5 days [15.5-61] vs 10 days [7-18], P < .01). Nonhome discharges were more common in neonates and infants (40% vs 36.8% vs 13.1%, P < .01). Conclusion: Mechanical mitral valve replacement is increasingly performed over time with acceptable in-hospital morbidity and mortality, especially in older children and adolescents. Neonates and infants are associated with worse hospital survival, prolonged hospitalization, and significant rates of nonhome discharges.

Risk factors and early outcomes of repeat sternotomy in 1960 adults with congenital heart disease: A 30-year, single-center study.

OBJECTIVE: Patients with congenital heart disease (CHD) increasingly live into adulthood, often requiring cardiac reoperation. We aimed to assess the outcomes of adults with CHD (ACHD) undergoing repeat sternotomy at our institution. METHODS: Review of our institution's cardiac surgery database identified 1960 ACHD patients undergoing repeat median sternotomy from 1993 to 2023. The primary outcome was early mortality, and the secondary outcome was a composite end point of mortality and significant morbidity. Univariable and multivariable logistic regression models were used to determine factors independently associated with outcomes. RESULTS: Of the 1960 ACHDs patient undergoing repeat sternotomy, 1183 (60.3%) underwent a second, third (n = 506, 25.8%), fourth (n = 168, 8.5%), fifth (n = 70, 3.5%), and sixth sternotomy or greater (n = 33, 1.6%). CHD diagnoses were minor complexity (n = 145, 7.4%), moderate complexity (n = 1380, 70.4%), and major complexity (n = 435, 22.1%). Distribution of procedures included valve (n = 549, 28%), congenital (n = 625, 32%), aortic (n = 104, 5.3%), and major procedural combinations (n = 682, 34.7%). Overall early mortality was 3.1%. Factors independently associated with early mortality were older age at surgery, CHD of major complexity, preoperative renal failure, preoperative ejection fraction, urgent operation, and postoperative blood transfusion. In addition, sternotomy number and bypass time were independently associated with the composite outcome. CONCLUSIONS: Despite the increase in early mortality with sternotomy number, sternotomy number was not independently associated with early mortality but with increased morbidity. Improvement strategies should target factors leading to urgent operations, early referral, along with operative efficiency including bypass time and blood conservation.

Systemic Atrioventricular Valve Surgery in Patients With Congenitally Corrected Transposition of the Great Vessels.

BACKGROUND: Limited data exist regarding the long-term outcomes of systemic atrioventricular valve (SAVV) intervention (morphologic tricuspid valve) in congenitally corrected transposition (ccTGA). OBJECTIVES: The goal of this study was to evaluate the mid- and long-term outcomes of SAVV surgery in ccTGA. METHODS: We performed a retrospective review of 108 ccTGA patients undergoing SAVV surgery from 1979 to 2022. The primary outcome was a composite endpoint of mortality, cardiac transplantation, or ventricular assist device implantation. The secondary outcome was long-term systemic right ventricular ejection fraction (SVEF). Cox proportional hazard and linear regression models were used to analyze survival and late SVEF data. RESULTS: The median age at surgery was 39.5 years (Q1-Q3: 28.8-51.0 years), and the median preoperative SVEF was 39% (Q1-Q3: 33.2%-45.0%). Intrinsic valve abnormality was the most common mechanism of SAVV regurgitation (76.9%). There was 1 early postoperative mortality (0.9%). Postoperative complete heart block occurred in 20 patients (18.5%). The actuarial 5-, 10-, and 20-year freedom from death or transplantation was 92.4%, 79.1%, and 62.9%. The 10- and 20-year freedom from valve reoperation was 100% and 93% for mechanical prosthesis compared with 56.6% and 15.7% for bioprosthesis (P < 0.0001). Predictors of postoperative mortality were age at operation (P = 0.01) and preoperative SVEF (P = 0.04). Preoperative SVEF (P < 0.001), complex ccTGA (P = 0.02), severe SAVV regurgitation (P = 0.04), and preoperative creatinine (P = 0.003) were predictors of late postoperative SVEF. CONCLUSIONS: SAVV surgery remains a valuable option for the treatment of patients with ccTGA, with low early mortality and satisfactory long-term outcomes, particularly in those with SVEF ≥40%. Timely referral and accurate patient selection are the keys to better long-term outcomes.

Mortality and Morbidity of Heart Failure Hospitalization in Adult Patients With Congenital Heart Disease.

BACKGROUND: Little is known about outcomes following heart failure (HF) hospitalization among adults with congenital heart disease (CHD) in the United States. We aim to compare the outcomes of HF versus non-HF hospitalizations in adults with CHD. METHODS AND RESULTS: Using a national deidentified administrative claims data set, patients with adult congenital heart disease (ACHD) hospitalized with and without HF (ACHDHF+, ACHDHF-) were characterized to determine the predictors of 90-day and 1-year mortality and quantify the risk of mortality, major adverse cardiac and cerebrovascular events, and health resource use. Cox proportional hazard regression was used to compare ACHDHF+ versus ACHDHF- for risk of events and health resource use. Of 26 454 unique ACHD admissions between January 1, 2010 and December 31, 2020, 5826 (22%) were ACHDHF+ and 20 628 (78%) were ACHDHF-. The ACHD HF+ hospitalizations increased from 6.6% to 14.0% (P<0.0001). Over a mean follow-up period of 2.23 ± 2.19 years, patients with ACHDHF+ had a higher risk of mortality (hazard ratio [HR], 1.86 [95% CI, 1.67-2.07], P<0.001), major adverse cardiac and cerebrovascular events (HR, 1.73 [95% CI, 1.63-1.83], P<0.001) and health resource use including rehospitalization (HR, 1.09 [95% CI, 1.05-1.14], P<0.001) and increased postacute care service use (HR, 1.56 [95% CI, 1.32-1.85], P<0.001). Cardiology clinic visits within 30 days of hospital admission were associated with lower 90-day and 1-year all-cause mortality (odds ratio [OR], 0.62 [95% CI, 0.49-0.78], P<0.001; OR, 0.69 [95% CI, 0.58-0.83], P<0.001, respectively). CONCLUSIONS: HF hospitalization is associated with increased risk of mortality and morbidity with high health resource use in patients with ACHD. Recent cardiology clinic attendance appears to mitigate these risks.

Novel approach to prenatal predictors of outcomes for fetuses with severe Ebstein anomaly.

OBJECTIVE: Ebstein anomaly (EA) is a cardiac malformation with highly variable presentation and severity with limited perinatal management options. We present incorporation of fetal lung measurements into a multidisciplinary evaluation for counseling and predicting postnatal outcomes in patients with severe EA. METHODS: Five fetuses with severe fetal EA were reviewed. Third trimester sonographic observed/expected total lung area (O/E TLA) and lung to head ratio (O/E LHR), fetal MRI total fetal lung volume ratio (O/E-TFLV), echocardiographic cardio-thoracic ratio (CT ratio), sonographic estimated fetal weight (EFW) by Hadlock formula and presence of hydrops, were used to guide perinatal management. RESULTS: Three of five had appropriate fetal growth, were delivered at term in a cardiac operative suite, and underwent immediate intervention with good neonatal outcomes. Two had severe fetal growth restriction (FGR), CT ratios > 0.8 and O/E LHR and TLA < 25%. One of which delivered prematurely with neonatal demise and one suffered in utero demise at 34 weeks. CONCLUSIONS: FGR, hydrops, increased CT ratio and reduced O/E LHR and TFLV are potential prognosticators of poor outcomes in severe EA, and should be validated in larger cohorts that would allow for a statistical analysis of the predictive utility of these measurements.

Pulmonary hypoplasia is associated with severe morbidityThere are limited prognosticating tools to risk stratify and guide management in cases of severe prenatal Ebstein anomaliesFetal MRI may improve prognostication for fetuses with EA.

Intraoperative Versus Postoperative Hydroxocobalamin for Vasoplegic Shock in Cardiothoracic Surgery.

OBJECTIVES: Hydroxocobalamin inhibits nitric oxide pathways contributing to vasoplegic shock in patients undergoing cardiopulmonary bypass (CPB). The objective of this study was to evaluate the effect of intraoperative versus postoperative application of hydroxocobalamin for vasoplegic shock in patients undergoing CPB. DESIGN: This was a historic cohort study. SETTING: The study was conducted at a quaternary academic cardiovascular surgery program. PARTICIPANTS: Adults undergoing cardiac surgery using CPB were participants in the study. INTERVENTIONS: Hydroxocobalamin (5 g) intravenously over 15 minutes. MEASUREMENTS AND MAIN RESULTS: The treatment groups were assigned based on the receipt location of hydroxocobalamin (ie, intensive care unit [ICU] versus operating room [OR]). The primary outcome was vasopressor-free days in the first 14 days after CPB. Of the 112 patients included, 37 patients received hydroxocobalamin in the OR and 75 in the ICU. Patients in the OR group were younger than those in the ICU group (57.5 v 63.9 years, p = 0.007), with statistically similar American Society of Anesthesiologists scores. The mean CPB duration was 3.4 hours in the OR group and 2.9 hours in the ICU group (p = 0.09). In both groups, the norepinephrine-equivalent dose of vasopressors at hydroxocobalamin was 0.27 µg/kg/min. Days alive and free of vasopressors were not different between the OR and ICU groups (estimated difference 0.48 [95% CI -1.76-2.72], p = 0.67). The odds of postoperative renal failure, mesenteric ischemia, ICU, hospital length of stay, and in-hospital mortality were also similar between groups. CONCLUSIONS: A difference in vasopressor-free days after CPB was not found between patients who received hydroxocobalamin intraoperatively versus postoperatively for vasoplegic shock.

Impact of heart failure on reoperation in adult congenital heart disease: An innovative machine learning model.

OBJECTIVES: The study objectives were to evaluate the association between preoperative heart failure and reoperative cardiac surgical outcomes in adult congenital heart disease and to develop a risk model for postoperative morbidity/mortality. METHODS: Single-institution retrospective cohort study of adult patients with congenital heart disease undergoing reoperative cardiac surgery between January 1, 2010, and March 30, 2022. Heart failure defined clinically as preoperative diuretic use and either New York Heart Association Class II to IV or systemic ventricular ejection fraction less than 40%. Composite outcome included operative mortality, mechanical circulatory support, dialysis, unplanned noncardiac reoperation, persistent neurologic deficit, and cardiac arrest. Multivariable logistic regression and machine learning analysis using gradient boosting technology were performed. Shapley statistics determined feature influence, or impact, on model output. RESULTS: Preoperative heart failure was present in 376 of 1011 patients (37%); those patients had longer postoperative length of stay (6 [5-8] vs 5 [4-7] days, P < .001), increased postoperative mechanical circulatory support (21/376 [6%] vs 16/635 [3%], P = .015), and decreased long-term survival (84% [80%-89%] vs 90% [86%-93%]) at 10 years (P = .002). A 7-feature machine learning risk model for the composite outcome achieved higher area under the curve (0.76) than logistic regression, and ejection fraction was most influential (highest mean |Shapley value|). Additional risk factors for the composite outcome included age, number of prior cardiopulmonary bypass operations, urgent/emergency procedure, and functionally univentricular physiology. CONCLUSIONS: Heart failure is common among adult patients with congenital heart disease undergoing cardiac reoperation and associated with longer length of stay, increased postoperative mechanical circulatory support, and decreased long-term survival. Machine learning yields a novel 7-feature risk model for postoperative morbidity/mortality, in which ejection fraction was the most influential.