Restricted Cusp Motion in Newly Implanted Tricuspid Bioprostheses: Incidence, Predictors, and Impact on Survival.

OBJECTIVE: This study aimed to investigate the occurrence of restricted cusp motion (RCM) at the time of bioprosthetic tricuspid valve replacement (TVR) and analyzed associated risk factors and outcomes. METHODS: This study involved adult patients who underwent TVR with a bioprosthesis at our institution between 2012 and 2022. Bioprosthetic cusp motion was analyzed de-novo through a detailed review of intraoperative transesophageal echocardiograms (TEE). Two models of porcine valves were implanted, the Hancock II bioprosthesis (Medtronic, Inc, Minneapolis, Minnesota) and the St. Jude Epic bioprosthesis (St. Jude Medical, St. Paul, Minnesota). RESULTS: Among the 476 patients who met the inclusion criteria, RCM was identified on the immediate post-bypass TEE in 150 (31.5%); there was complete immobility of the cusp in 63 patients (13.2%) and limited movement of a cusp in 87 patients (18.3%). In a multivariable logistic regression analysis, the Hancock II model (OR 6.15, p<0.001), a larger orifice area (per IQR increase, OR 1.58, p=0.017), a smaller body surface area (per IQR increase, OR 0.68, p=0.040), and a lower ejection fraction (per IQR increase, OR 0.60, p=0.033) were independently associated with having RCM. Cox regression adjusting for 15 covariates revealed that RCM at time of TVR was independently associated with an increased risk of mortality (HR 1.35, p=0.049). CONCLUSIONS: This study revealed a high incidence of restricted cusp motion in bioprosthetic valves in the tricuspid position detected shortly post-implantation, which was associated with increased late mortality. To reduce the probability of restricted cusp motion, it is important to select the appropriate prosthesis model and size, particularly in small patients.

Heart Transplantation for Ebstein Anomaly due to Late Surgical Presentation.

Ebstein anomaly is a myopathy of the right ventricle characterized by failure of tricuspid valve delamination with accompanying tricuspid regurgitation. Its rarity, considerable anatomic variability, and frequent absence of symptoms can make the timing of surgery challenging. Contemporary tricuspid repair techniques can be performed with low mortality and bidirectional cavopulmonary anastomosis reduces the risk of operation when right ventricular function is poor. Here, we present a patient who presented late for surgery, failed high-risk conventional surgery and required heart transplantation.

Delayed Sternal Closure vs Emergency Sternal Reopening in Adults with Congenital Heart Disease.

BACKGROUND: Limited data exist regarding outcomes of delayed sternal closure (DSC) in adults with congenital heart disease (ACHD). METHODS: We reviewed 159 ACHD patients undergoing cardiac surgery 1993-2023, who required DSC (open sternum at the end of operation, n=112) or ESR (sternum emergently reopened, n=47). Regression models were performed to determine factors associated with outcomes. RESULTS: Of 112 patients undergoing DSC, 87 patients (77.6%) underwent DSC ≤4 days, and 25 patients (22.3%) >4 days. The most common operations were valve (n=35, 31.2%), aortic (n=33, 29.4%), and right ventricular outflow tract procedures (n=23, 20.5%). Median time to chest closure was 2 days (interquartile range 1, 5). Apart from gender, baseline characteristics were similar between DSC groups. A stepwise increase in early mortality was observed from DSC≤4 days to DSC>4 days (6.8% vs 32%), as well as incidence of early complications, except sternal infection. Risk factors associated with early mortality were age (p=0.02), DSC >4 days (p<0.001), hemodynamic indication (p=0.03), and single ventricle (p=0.02). On multivariable analysis, lower ejection fraction (p=0.04), hemodynamic indication (p=0.02), single ventricle (p=0.004), and diabetes mellitus (p=0.03) were predictors of prolonged time to chest closure. Amongst hospital survivors, there was no difference in late survival between patients undergoing DSC ≤4 days vs >4 days (p=0.48). CONCLUSIONS: Brief duration of DSC in ACHD patients is associated with low morbidity and mortality. Higher early mortality and complications were observed among patients who did not achieve chest closure within 4 days.

Simultaneous Tricuspid Valve Repair at the Time of Mitral Valve Surgery: Determinants of Postoperative Pacemaker Implantation.

OBJECTIVE: Guidelines recommend tricuspid valve (TV) repair for patients with severe tricuspid valve regurgitation (TR) undergoing surgery for degenerative mitral valve (MV) disease, but management of ≤ moderate TR is controversial. This study examines the incidence and causes of bradyarrhythmias leading to PPM implantation. METHODS: Review of patients undergoing simultaneous TV repair and MV surgery for degenerative MV disease from 2001 to 2022 (N=404). Primary endpoint was the incidence of postoperative PPM implantation. Secondary endpoints included the incidence of high-degree AV block and overall survival. RESULTS: All patients underwent TV repair at the time of MV surgery; 332 (82%) underwent MV repair and 72 (18%) MV replacement. Tricuspid valve repair techniques included flexible band (n=258, 63.8%), DeVega annuloplasty (n=78, 19.3%), complete flexible ring (n=49, 12.1%), and incomplete rigid ring (n=19, 4.7%). The 30-day mortality was 0.5% (n=2). A total of 35 (8.7%) patients had a PPM implanted postoperatively, 26 (6.4%) for high-degree AV block. On multivariable analysis, only older age was associated with PPM implantation. Patients who received a PPM due to high-degree AV block had reduced overall survival (Figure, p=0.01). CONCLUSIONS: Need for permanent pacing following TV repair at the time of MV surgery is not uncommon, but there are few modifiable factors that might reduce this risk. Careful selection of patients with less-than-severe TR and surgical techniques may reduce PPM-related risks and complications.

2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines.

AIM: The "2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy" provides recommendations to guide clinicians in the management of patients with hypertrophic cardiomyopathy. METHODS: A comprehensive literature search was conducted from September 14, 2022, to November 22, 2022, encompassing studies, reviews, and other evidence on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through May 23, 2023, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate. STRUCTURE: Hypertrophic cardiomyopathy remains a common genetic heart disease reported in populations globally. Recommendations from the "2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy" have been updated with new evidence to guide clinicians.

Outcomes of surgical septal myectomy for obstructive hypertrophic cardiomyopathy after previous septal reduction therapy.

OBJECTIVE: To compare early and late outcomes of septal myectomy in patients with obstructive hypertrophic cardiomyopathy who presented with residual or recurrent left ventricular outflow tract (LVOT) obstruction after previous septal-reduction therapy (SRT). METHODS: From January 1989 to March 2022, 145 patients underwent reintervention by septal myectomy for residual LVOT obstruction after previous SRT; 72 patients had previous alcohol septal ablation (ASA) and 73 had previous surgical septal myectomy. Baseline patient characteristics, echocardiographic parameters, and surgical outcomes were compared between these 2 groups. RESULTS: Patients who had previous ASA were more likely to be male (50.0% vs 30.1%; P = .015), be older (median age 57.5 years vs 48.3 years; P < .001), and have a greater body mass index (32.7 kg/m2 vs 30.0 kg/m2; P = .011). After repeat SRT by septal myectomy, there was no significant difference in the incidence of postoperative complete heart block, necessitating permanent pacemaker, between the 2 groups (8.3% vs 2.7%; P = .151). One (0.7%) patient died within 30 days of surgery. Over a median follow-up of 7.5 years (interquartile range, 3.0-13.8), there were 20 deaths. Kaplan-Meier 5-, 10-, and 15-year survival rates were 100%, 91%, and 76% for the previous septal myectomy group, and 93%, 81%, and 64% for the previous ASA group (P = .207). CONCLUSIONS: Septal myectomy for residual or recurrent LVOT obstruction in patients who had previous ASA is safe, with an acceptably low rate of postoperative complete heart block. Surgical outcomes and late survival rates in patients with complete heart block ASA were satisfactory and comparable with patients who underwent repeat myectomy.

2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines.

AIM: The "2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy" provides recommendations to guide clinicians in the management of patients with hypertrophic cardiomyopathy. METHODS: A comprehensive literature search was conducted from September 14, 2022, to November 22, 2022, encompassing studies, reviews, and other evidence on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through May 23, 2023, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate. STRUCTURE: Hypertrophic cardiomyopathy remains a common genetic heart disease reported in populations globally. Recommendations from the "2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy" have been updated with new evidence to guide clinicians.

Histone Modifications and miRNA Perturbations Contribute to Transcriptional Dysregulation of Hypertrophy in Obstructive Hypertrophic Cardiomyopathy.

Background: Recently, we demonstrated transcriptional downregulation of hypertrophy pathways in myectomy tissue derived from patients with obstructive hypertrophic cardiomyopathy (HCM) despite translational activation of hypertrophy pathways. The mechanisms and modifiers of this transcriptional dysregulation in HCM remain unexplored. We hypothesized that miRNA and post-translational modifications of histones contribute to transcriptional dysregulation in HCM. Methods: First, miRNA-sequencing and chromatin immunoprecipitation sequencing (ChIP-seq) were performed on HCM myectomy tissue and control donor hearts to characterize miRNA and differential histone marks across the genome. Next, the differential miRNA and histone marks were integrated with RNA-sequencing (RNA-seq) data. Finally, the effects of miRNA and histones were removed in silico to determine their necessity for transcriptional dysregulation of pathways. Results: miRNA-analysis identified 19 differentially expressed miRNA. ChIP-seq analysis identified 2,912 (7%) differential H3K4me3 peaks, 23,339 (21%) differential H3K9ac peaks, 33 (0.05%) differential H3K9me3 peaks, 58,837 (42%) differential H3K27ac peaks, and 853 (3%) differential H3K27me3 peaks. Univariate analysis of concordance between H3K9ac with RNA-seq data showed activation of cardiac hypertrophy signaling, while H3K27me showed downregulation of cardiac hypertrophy signaling. Similarly, miRNAs were predicted to result in downregulation of cardiac hypertrophy signaling. In silico knock-out that effects either miRNA or histones attenuated transcriptional downregulation while knocking out both abolished downregulation of hypertrophy pathways completely. Conclusion: Myectomy tissue from patients with obstructive HCM shows transcriptional dysregulation, including transcriptional downregulation of hypertrophy pathways mediated by miRNA and post-translational modifications of histones. Cardiac hypertrophy loci showed activation via changes in H3K9ac and a mix of activation and repression via H3K27ac.

Single-Center Prospective Study of Cross-Clamp vs Balloon Occlusion in Robotic Mitral Surgery.

BACKGROUND: Transthoracic aortic cross-clamp and endoaortic balloon occlusion have both been shown to have comparable safety profiles for aortic occlusion. Because most surgeons use only one technique, we sought to compare the outcomes when a homogeneous group of surgeons changed their occlusion technique from aortic cross-clamp to balloon occlusion. METHODS: We changed our technique from aortic cross-clamp to balloon occlusion in November 2022. This allowed us to conduct a prospective treatment comparison study in the same group of surgeons. Propensity score matching was used to match cases (balloon occlusion) 1:3 to controls (aortic cross-clamp) based on age, sex, body mass index, concomitant maze procedure, and tricuspid valve repair. RESULTS: Total of 411 patients underwent robotic mitral surgery from 2020 through 2023. Propensity score matching was used to match 56 balloon occlusion patients to 168 aortic cross-clamp patients. The 224 patients were a median age of 65 years (interquartile range, 55.6-70.0 years), and 119 (53%) were men. All valves were successfully repaired. Balloon occlusion had a shorter median cardiopulmonary bypass (CPB) time compared with aortic cross-clamp (84.0 vs 94.5 minutes, P = .006). Median cross-clamp time (64.0 vs 64.0 minutes, P = .483) and total surgery time (5.9 vs 6.1 hours, P = .495) did not differ between groups. There were no in-hospital deaths. There were 5 surgeons who performed various combinations of console and bedside roles. CPB, cross-clamp, and surgery durations were not significantly affected by the different surgeon combinations. CONCLUSIONS: Compared with aortic cross-clamp, balloon occlusion has similar perioperative and early postoperative outcomes. Additionally, it likely introduces a 10-minute reduction in total CPB time.

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.

Obstruction in Hypertrophic Cardiomyopathy: Many Faces.

Hypertrophic cardiomyopathy (HCM), the most common inherited cardiomyopathy, exhibits left ventricular hypertrophy not secondary to other causes, with varied phenotypic expression. Enhanced actin-myosin interaction underlies excessive myocardial contraction, frequently resulting in dynamic obstruction within the left ventricle. Left ventricular outflow tract obstruction, occurring at rest or with provocation in 75% of HCM patients, portends adverse prognosis, contributes to symptoms, and is frequently a therapeutic target. Transthoracic echocardiography plays a crucial role in the screening, initial diagnosis, management, and risk stratification of HCM. Herein, we explore echocardiographic evaluation of HCM, emphasizing Doppler assessment for obstruction. Echocardiography informs management strategies through noninvasive hemodynamic assessment, which is frequently obtained with various provocative maneuvers. Recognition of obstructive HCM phenotypes and associated anatomical abnormalities guides therapeutic decision-making. Doppler echocardiography allows monitoring of therapeutic responses, whether it be medical therapies (including cardiac myosin inhibitor therapy) or septal reduction therapies, including surgical myectomy and alcohol septal ablation. This article discusses the hemodynamics of obstruction and practical application of Doppler assessment in HCM. In addition, it provides a visual atlas of obstruction in HCM, including high-quality figures and complementary videos that illustrate the many facets of dynamic obstruction.

A Multi-Omics Atlas of Sex-Specific Differences in Obstructive Hypertrophic Cardiomyopathy.

Background: Hypertrophic cardiomyopathy (HCM) is a common genetic heart disease. Women with HCM tend to have a later onset but more severe disease course. However, the underlying pathobiological mechanisms for these differences remain unknown. Methods: Myectomy samples from 97 patients (53 males/44 females) with symptomatic obstructive HCM and 23 control cardiac tissues were included in this study. RNA-sequencing was performed on all samples. Mass spectrometry-based proteomics and phosphoproteomics was performed on a representative subset of samples. Results: The transcriptome, proteome, and phosphoproteome was similar between sexes and did not separate on PCA plotting. Overall, there were 482 differentially expressed genes (DEGs) between control females and control males while there were only 53 DEGs between HCM females and HCM males. There were 1963 DEGs between HCM females and control females compared to 1064 DEGs between HCM males and control males. Additionally, there was increased transcriptional downregulation of hypertrophy pathways in HCM females and in HCM males. HCM females had 119 differentially expressed proteins compared to control females while HCM males only had 27 compared to control males. Finally, the phosphoproteome showed females had 341 differentially phosphorylated proteins (DPPs) compared to controls while males only had 184. Interestingly, there was hypophosphorylation and inactivation of hypertrophy pathways in females but hyperphosphorylation and activation in males. Conclusion: There are subtle, but biologically relevant differences in the multi-omics profile of HCM. This study provides the most comprehensive atlas of sex-specific differences in the transcriptome, proteome, and phosphoproteome present at the time of surgical myectomy for obstructive HCM.

A Case Series of Minimally Invasive Robotic-Assisted Resection of Cardiac Papillary Fibroelastoma: The Mayo Clinic Experience.

Papillary fibroelastomas (PFEs) are small, slowly growing benign cardiac tumors with clinically significant risk of embolization. Surgical excision is the definitive treatment of symptomatic PFE and is conventionally performed through a median sternotomy. In this study, we report a series of 12 patients, who underwent robotic-assisted PFE removal at the Mayo Clinic. PFE involved the mitral valve, left atrium, and tricuspid valve. No major complications occurred after the procedure, and most patients were discharged 4 days after the surgery. On follow-up, 1 patient demonstrated pericarditis.

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.

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.

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.

Outcomes of aortic surgery in patients with Takayasu arteritis.

OBJECTIVE: To investigate the presentation, aortic involvement, and surgical outcomes in patients with Takayasu arteritis undergoing aortic surgery. METHODS: We queried our surgical database for patients with Takayasu arteritis who underwent aortic surgery from 1994 to 2022. RESULTS: There were a total of 31 patients with Takayasu arteritis who underwent aortic surgery. Patients' median age at the time of diagnosis was 35.0 years (interquartile range, 25.0-42.0). The majority were female (n = 27, 87.0%). Most patients (n = 28, 90.3%) were diagnosed before surgery, and 3 patients (9.6%) were diagnosed perioperatively. The median time interval from diagnosis to surgery was 2.8 years (interquartile range, 0.5-13.9). The most common presentation was ascending aorta aneurysm (n = 22, 70.9%), and severe aortic regurgitation was the most common valve insufficiency (n = 17, 54.8%). The most common operation was ascending aorta replacement (n = 20, 64.5%), and aortic valve replacement was the most common valve intervention (n = 17, 54.8%). Active vasculitis was identified in 2 (11.7%) aortic valve specimens. Early mortality was 6.5% (n = 2). A total of 6 deaths occurred over a median follow-up of 13.1 years (interquartile range, 6.1-25.2). Survival at 10 years was 86.7% (95% CI, 75.4-99.7). A total of 5 patients (16.1%) required a subsequent operation in a median of 1.9 years (interquartile range, 0.2-7.4). Freedom from reoperation was 96.9% (95% CI, 90.1-100) at 1 year, 89.4% (95% CI, 78.7-100.0) at 5 years, and 77.5% (95% CI, 61.2-98.1) at 10 and 15 years. CONCLUSIONS: Ascending aorta aneurysm and aortic valve regurgitation are the most frequent presentations in patients with Takayasu arteritis requiring aortic surgery. Surgery in these individuals is safe, with acceptable short- and long-term results.