Improvement in Sexual Dysfunction in Patients With Hypertrophic Cardiomyopathy Undergoing Septal Myectomy: A Prospective Study.

Background: Septal myectomy improves symptoms in the majority of patients with obstructive hypertrophic cardiomyopathy (HCM), but there are limited prospective data on functional outcomes after operation. Objectives: The authors investigated quality of life measures and prevalence of sexual dysfunction before and after septal myectomy for obstructive HCM. Methods: Between January 2018 and October 2019, 436 patients underwent transaortic septal myectomy at our clinic. All patients were screened for eligibility, and 197 (45.2%) were enrolled in this prospective survey study. Patients received a questionnaire pertaining to quality of life and sexual health before and within 4 to 6 months postoperatively, and 113 (57.4%) completed the follow-up survey. Results: The mean age of the 54 (47.8%) women and 59 (52.2%) men was 54.7 ± 14.1 years. Quality of life, including both mental and physical components, improved significantly in both men (P < 0.001) and women (P < 0.001). Women reported mild sexual dysfunction at baseline, and following septal myectomy, they experienced significant (P < 0.05) improvement in most domains pertaining to sexual health. In men, the International Index of Erectile Function median score was 23 (IQR: 7.0-29.5), which is consistent with mild dysfunction at baseline, and there was significant improvement following surgery in young (age ≤55 years) men (P < 0.001). Conclusions: Quality of life is significantly improved following septal myectomy in patients with obstructive HCM. Both women and men reported mild sexual dysfunction at baseline, and women and younger men (age ≤55 years) experienced significant improvements in sexual health.

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.

Improvement in gastrointestinal bleeding after septal myectomy for hypertrophic cardiomyopathy.

OBJECTIVE: Patients with obstructive hypertrophic cardiomyopathy may have occult gastrointestinal bleeding. In this study, we analyzed outcomes of septal myectomy in patients who had a history of gastrointestinal bleeding preoperatively to understand patient characteristics and impact of septal reduction on recurrent gastrointestinal bleeding. METHODS: We analyzed 73 adult patients who had a history of gastrointestinal bleeding before transaortic septal myectomy for obstructive hypertrophic cardiomyopathy and compared outcomes to 219 patients without gastrointestinal bleeding preoperatively. RESULTS: Patients with preoperative history of gastrointestinal bleeding were older (median (IQR) age, 65 (59-69) years, P < .001) and were more likely to have systemic hypertension (70% vs 53%, P = .020) and coronary artery disease (25% vs 13%, P = .026). Preoperatively, patients with gastrointestinal bleeding had a larger left atrial volume index (median, 53 mL/m2; interquartile range, 42-67; P = .006) and greater right ventricular systolic pressure (median, 36 mm Hg; interquartile range, 32-49; mm Hg, P = .005) but no significant difference in severity of outflow tract obstruction (P = .368). There were no perioperative deaths. The estimated 5- and 10-year survivals were 96.6% and 81.8%, respectively. At a median of 3.4 (interquartile range, 1.9-9.1) years after septal myectomy, 11 patients (15%) had recurrence of gastrointestinal bleeding, which was attributed to angiodysplasia or unknown causes in 6 patients (8%). CONCLUSIONS: Patients with a preoperative history of gastrointestinal bleeding have favorable short- and long-term outcomes after septal myectomy for obstructive hypertrophic cardiomyopathy. Remission of gastrointestinal bleeding was observed in 85% of patients postprocedure, and only 8% of the patients had recurrent gastrointestinal bleeding due to angiodysplasia or unknown causes.

Aortic valve regurgitation following transaortic septal myectomy for obstructive hypertrophic cardiomyopathy: Incidence and influence on late outcomes.

OBJECTIVE: In this study, we describe the incidence, sites of valve injury, and the influence of aortic valve regurgitation (AR) on outcomes of septal myectomy for obstructive hypertrophic cardiomyopathy. METHODS: We analyzed patients who underwent transaortic septal myectomy for obstructive hypertrophic cardiomyopathy from 2001 to 2022. The primary study end point was incidence of procedure-related AR, defined as the need for an unplanned aortic valve (AV) procedure or new-onset moderate AR on early postoperative echocardiography. RESULTS: There were 2807 patients who underwent transaortic septal myectomy for hypertrophic cardiomyopathy and had pre- and postoperative transthoracic echocardiograms. Procedure-related AR was observed in 55 (2%) patients; 27 (1%) required unplanned AV procedures at the time of myectomy, and 29 (1%) additional patients developed moderate AR postoperatively. During follow-up, 9 total patients underwent late AV reoperation, 1 patient who developed new moderate AR postoperatively required late AVR due to severe calcific AS, and none of the patients who had unplanned AV procedures required late reoperation. The overall cumulative incidence of AV reoperation at 10 and 15 years was 1% and 5%. The predicted probability of moderate or severe AR at 5 and 10 years was 1.4% and 1.8%, respectively. There was no difference in survival comparing patients with or without early postoperative mild or worse AR (P = .69). CONCLUSIONS: Procedure-related AR was observed in 2% of patients undergoing transaortic septal myectomy, and unplanned AV procedures were necessary for half of these patients. Intraoperative identification and valve repair mitigate the impact of cusp injury on late reintervention and survival.

Outcomes of concomitant myectomy and left ventricular apical aneurysm repair in patients with hypertrophic cardiomyopathy.

OBJECTIVES: Hypertrophic cardiomyopathy with left ventricular apical aneurysm is a phenotype associated with a 4-fold increase in the risk for sudden cardiac death. In this study, we describe the surgical outcome of concomitant apical aneurysm repair in patients undergoing transapical myectomy for hypertrophic cardiomyopathy. METHODS: We identified 67 patients with left ventricular apical aneurysms who underwent transapical myectomy and apical aneurysm repair between July 2000 and August 2020. Long-term survival was compared with that of 2746 consecutive patients undergoing transaortic septal myectomy for obstructive hypertrophic cardiomyopathy with subaortic obstruction. RESULTS: Transapical myectomy was indicated for midventricular obstruction (n = 44) or left ventricular remodeling for diastolic heart failure (n = 29). Preoperatively, 74.6% (n = 50) of patients were in New York Heart Association class III/IV heart failure, and 34.3% (n = 23) of patients had experienced syncope or presyncope. Atrial fibrillation was documented in 22 patients (32.8%), and episodes of ventricular arrhythmias were recorded in 30 patients (44.8%). Thrombus was present in the apical aneurysm in 6 patients. During a median (interquartile range) follow-up of 4.9 (1.8-7.6) years, the estimated 1- and 5-year survivals were 98.5% and 94.5%, respectively, which were not significantly different from that of patients undergoing transaortic septal myectomy for obstructive hypertrophic cardiomyopathy (P = .52) or an age- and sex-matched US general population (P = .40). CONCLUSIONS: Apical aneurysm repair in conjunction with septal myectomy is a safe procedure, and the good long-term survival of patients suggests that the procedure may reduce cardiac-related death in this high-risk hypertrophic cardiomyopathy population.

Multi-Omic Architecture of Obstructive Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is characterized by asymmetric left ventricular hypertrophy. Currently, hypertrophy pathways responsible for HCM have not been fully elucidated. Their identification could serve as a nidus for the generation of novel therapeutics aimed at halting disease development or progression. Herein, we performed a comprehensive multi-omic characterization of hypertrophy pathways in HCM. METHODS: Flash-frozen cardiac tissues were collected from genotyped HCM patients (n=97) undergoing surgical myectomy and tissue from 23 controls. RNA sequencing and mass spectrometry-enabled deep proteome and phosphoproteomic assessment were performed. Rigorous differential expression, gene set enrichment, and pathway analyses were performed to characterize HCM-mediated alterations with emphasis on hypertrophy pathways. RESULTS: We identified transcriptional dysregulation with 1246 (8%) differentially expressed genes and elucidated downregulation of 10 hypertrophy pathways. Deep proteomic analysis identified 411 proteins (9%) that differed between HCM and controls with strong dysregulation of metabolic pathways. Seven hypertrophy pathways were upregulated with antagonistic upregulation of 5 of 10 hypertrophy pathways shown to be downregulated in the transcriptome. Most upregulated hypertrophy pathways encompassed the rat sarcoma-mitogen-activated protein kinase signaling cascade. Phosphoproteomic analysis demonstrated hyperphosphorylation of the rat sarcoma-mitogen-activated protein kinase system suggesting activation of this signaling cascade. There was a common transcriptomic and proteomic profile regardless of genotype. CONCLUSIONS: At time of surgical myectomy, the ventricular proteome, independent of genotype, reveals widespread upregulation and activation of hypertrophy pathways, mainly involving the rat sarcoma-mitogen-activated protein kinase signaling cascade. In addition, there is a counterregulatory transcriptional downregulation of the same pathways. Rat sarcoma-mitogen-activated protein kinase activation may serve a crucial role in hypertrophy observed in HCM.

Preoperative left ventricular longitudinal strain predicts outcome of septal myectomy for obstructive hypertrophic cardiomyopathy.

OBJECTIVE: The objective of this study was to determine the characteristics of longitudinal strain and its effect on outcomes in patients with obstructive hypertrophic cardiomyopathy (HCM) who underwent septal myectomy. METHODS: We reviewed patients with obstructive HCM who underwent septal myectomy at our clinic from 2007 to 2016. Data of those who had strain echocardiography within 6 months before isolated myectomy were analyzed. RESULTS: The median age of the 857 patients studied was 55 (interquartile range [IQR], 44-63) years, and 451 (52.6%) were male. Left ventricular ejection fraction was 71% (IQR, 67%-74%), and the resting peak outflow tract gradient was 58 (IQR, 27-85) mm Hg. The median global longitudinal strain (GLS) was -14.6% (IQR, -12.0% to -17.3%). Regional longitudinal strain was nonuniform as reflected by more normal values in apical segments and more abnormal in basal segments. Moreover, GLS correlated poorly with ejection fraction and outflow tract gradient. In 64 patients who had postoperative strain echocardiography, GLS was comparable before and after septal myectomy, but regional strain was more uniform after myectomy. Over a follow-up of 8.3 (IQR, 6.5-10.3) years, when patients were equally stratified according to GLS (cutoff, -14.64%), the group with worse GLS had significantly poorer survival compared with the better GLS group (P = .002). Left ventricular ejection fraction had no association with survival. CONCLUSIONS: Left ventricular longitudinal strain is nonuniform and might be significantly reduced in patients with obstructive HCM. Septal myectomy does not impair GLS but is associated with more uniform regional strains. Most importantly, reduced GLS preoperatively is strongly and independently associated with increased all-cause mortality after septal myectomy for obstructive HCM.

Is anterior mitral valve leaflet length important in outcome of septal myectomy for obstructive hypertrophic cardiomyopathy?

OBJECTIVES: Elongation of mitral valve leaflets is a phenotypic feature of hypertrophic cardiomyopathy, and some surgeons advocate plication of the anterior leaflet at the time of septal myectomy. The present study investigates mitral valve leaflet length and outcomes of patients undergoing septal myectomy for obstructive hypertrophic cardiomyopathy. METHODS: We reviewed the records and echocardiograms of 564 patients who underwent transaortic septal myectomy for obstructive hypertrophic cardiomyopathy between February 2015 and April 2018. Extended septal myectomy without plication of the anterior leaflet was the standard procedure. From intraoperative prebypass transesophageal echocardiograms, we measured anterior and posterior mitral valve leaflets and their coaptation length. For comparison, we performed these mitral valve leaflet measurements in 90 patients who underwent isolated coronary artery bypass grafting and 92 patients undergoing aortic valve replacement in the same period. Among patients with hypertrophic cardiomyopathy undergoing septal myectomy, we assessed left ventricular outflow tract gradient relief and 1-year survival in relation to leaflet length. RESULTS: Median patient age (interquartile range) was 60.3 (50.2-67.7) years, and 54.1% were male. Concomitant mitral valve repair was performed in 36 patients (6.4%), and mitral valve replacement was performed in 8 patients (1.4%), primarily for intrinsic mitral valve disease. Patients in the hypertrophic cardiomyopathy cohort had significantly longer mitral valve leaflet measurements compared with patients undergoing coronary artery bypass grafting or aortic valve replacement (P < .001 for all 3 measurements). Preoperative resting left ventricular outflow tract gradients were not related to leaflet length (<30 mm, median 49 [21, 81.5] mm Hg vs ≥30 mm, 50.5 [21, 77] mm Hg; P = .76). Further, gradient reduction after myectomy was not related to leaflet length; patients with less than 30 mm anterior leaflet length had a median gradient reduction of 33 (69, 6) mm Hg compared with 36.5 (62, 6) mm Hg for patients with leaflet length 30 mm or more (P = .36). Anterior mitral valve leaflet length was not associated with increased 1-year mortality (P = .758). CONCLUSIONS: Our study confirms previous findings that patients with hypertrophic cardiomyopathy have slight (5 mm) elongation of mitral valve leaflets. In contrast to other reports, increased anterior mitral valve leaflet length was not associated with higher left ventricular outflow tract gradients. Importantly, we found no significant relationship between anterior mitral valve leaflet length and postoperative left ventricular outflow tract resting gradients or gradient relief. Thus, in the absence of intrinsic mitral valve disease, transaortic septal myectomy with focus on extending the excision beyond the point of septal contact is sufficient for almost all patients.

Optimal Management of Mitral Regurgitation Due to Ruptured Mitral Chordae Tendineae in Patients With Hypertrophic Cardiomyopathy.

There is continued controversy regarding surgical management of patients with hypertrophic cardiomyopathy (HCM) and intrinsic mitral valve disease; some clinicians favor prosthetic replacement as this corrects left ventricular outflow tract (LVOT) obstruction and valve leakage. In this study, we investigated the management and late outcome of operation for mitral regurgitation (MR) due to ruptured chordae tendineae in patients with HCM. We analyzed 49 consecutive patients with HCM and MR due to ruptured mitral valve chordae. Echocardiograms and operative reports were reviewed to classify valve anatomy and surgical methods. Information on late outcomes was obtained from electronic medical records and follow-up surveys. The mean age of the 36 men and 13 women was 61.9 ± 12.5 years; significant resting or provoked LVOT obstruction was present at the time of surgery in 46 patients. During the index operation, mitral valve repair was performed in 45 patients, and prosthetic replacement was necessary for 4 patients. Concomitant septal myectomy was performed in 46 patients. There were no hospital deaths or deaths within 30 days of operation. Five and ten-year survival estimates (Kaplan-Meier) were 92% and 71%. During follow-up at a median of 7.9 years, 3 patients underwent reoperation for MV replacement, 5 days, 3 years, and 14 years following valve repair. Ruptured mitral chordae may result in severe mitral valve regurgitation in patients with hypertrophic cardiomyopathy. Valvuloplasty at the time of septal myectomy is safe with an acceptably low rate of recurrent MR requiring prosthetic replacement.

Cardiopulmonary Exercise Testing in Athletes With Hypertrophic Cardiomyopathy.

Patients with hypertrophic cardiomyopathy (HCM) have historically been restricted from athletic participation because of the perceived risk of sudden cardiac death. More contemporary research has highlighted the relative safety of competitive athletics with HCM. However, lack of published data on reference values for cardiopulmonary exercise testing (CPET) complicates clinical management and counseling on sports participation in the individual athlete. We conducted a single-center, retrospective cohort study to investigate CPET in athletes with HCM and clinical characteristics associated with objective measures of aerobic capacity. We identified 58 athletes with HCM (74% male, mean age 18 ± 3 years, mean left ventricular (LV) wall thickness 20 ± 7 mm). LV outflow tract obstruction was present in 22 (38%). A total of 15 (26%) athletes were taking a ß blocker (BB), but only 4 (7%) reported exertional symptoms. Overall, exercise capacity was mildly reduced, with a peak myocardial oxygen consumption (peak VO2) of 37.9 ml/min/kg (83% of predicted peak VO2). Both LV outflow tract obstruction and BB use were associated with reduced exercise capacity. Limited peak heart rate was more common in athletes taking BB (47% vs 9%, p = 0.002). At a mean 5.6 years follow-up, 5 patients underwent myectomy (9%), and 8 (14%) received an implantable cardioverter defibrillator (ICD) for primary prevention. One individual with massive LV hypertrophy experienced recurrent ICD shocks for ventricular fibrillation and underwent myectomy 7 years after initial evaluation and was no longer participating in sports. There were no deaths over the follow-up period. In conclusion, the prognostic role of CPET remains unclear in athletes with HCM. Mildly reduced exercise capacity was common; however, reduced peak VO2 did not correlate with symptom status or clinical outcomes. A significant proportion went on to require myectomy and/or ICD, thus highlighting the need for close follow-up. These data provide some initial insight into the clinical evaluation of "real world" athletes with HCM; however, further study is warranted to help guide shared decision-making, return-to-play discussions, and the potential long-term safety of competitive athletic participation.

Prevalence and influence of pulmonary hypertension in patients with obstructive hypertrophic cardiomyopathy undergoing septal myectomy.

OBJECTIVES: Pulmonary hypertension (PH) is an independent predictor of all-cause mortality among patients with obstructive and nonobstructive hypertrophic cardiomyopathy (HCM). However, there is little information on the influence of coexisting PH on long-term survival following septal myectomy. This study investigates the prevalence of PH among patients with obstructive HCM undergoing septal myectomy and analyzes patient survival and the course of PH after operation. METHODS: We included 1342 patients with obstructive HCM who had Doppler echocardiographic estimates of the right ventricular systolic pressure (RVSP) before and after transaortic septal myectomy. PH was defined as RVSP ≥35 mm Hg, with ≥50 mm Hg categorized as moderate-to-severe PH. A multivariable Cox proportional hazards model was used to identify characteristics associated with survival, and longitudinal trends in RVSP were modeled with generalized least squares analysis. RESULTS: Patients underwent operations from 1989 to 2019. The median age was 57.9 years (interquartile range, 47.4-66.7 years); 49.5% were women. Preoperatively, PH was present in 47.8% of patients, and 14.4% had moderate-to-severe PH. Higher preoperative RVSP was independently associated with overall mortality in the multivariable Cox model. Among patients with moderate to severe preoperative RVSP elevation, postoperative RVSP decreased from baseline by a median of 12 mm Hg. CONCLUSIONS: Preoperative PH is independently associated with late mortality following septal myectomy, and the magnitude of preoperative RVSP was associated with a postoperative decrease in pulmonary pressure. The influence of PH on late postoperative survival may influence the timing of operation in patients who are candidates for septal myectomy.

Assessment of Clinician Diagnostic Concordance With Video Telemedicine in the Integrated Multispecialty Practice at Mayo Clinic During the Beginning of COVID-19 Pandemic From March to June 2020.

Importance: There was a shift in patient volume from in-person to video telemedicine visits during the COVID-19 pandemic. Objective: To determine the concordance of provisional diagnoses established at a video telemedicine visit with diagnoses established at an in-person visit for patients presenting with a new clinical problem. Design, Setting, and Participants: This is a diagnostic study of patients who underwent a video telemedicine consultation followed by an in-person outpatient visit for the same clinical problem in the same specialty within a 90-day window. The provisional diagnosis made during the video telemedicine visit was compared with the reference standard diagnosis by 2 blinded, independent medical reviewers. A multivariate logistic regression model was used to determine factors significantly related to diagnostic concordance. The study was conducted at a large academic integrated multispecialty health care institution (Mayo Clinic locations in Rochester, Minnesota; Scottsdale and Phoenix, Arizona; and Jacksonville, Florida; and Mayo Clinic Health System locations in Iowa, Wisconsin, and Minnesota) between March 24 and June 24, 2020. Participants included Mayo Clinic patients residing in the US without age restriction. Data analysis was performed from December 2020 to June 2021. Exposures: New clinical problem assessed via video telemedicine visit to home using Zoom Care Anyplace integrated into Epic. Main Outcomes and Measures: Concordance of provisional diagnoses established over video telemedicine visits compared against a reference standard diagnosis. Results: There were 2393 participants in the analysis. The median (IQR) age of patients was 53 (37-64) years; 1381 (57.7%) identified as female, and 1012 (42.3%) identified as male. Overall, the provisional diagnosis established over video telemedicine visit was concordant with the in-person reference standard diagnosis in 2080 of 2393 cases (86.9%; 95% CI, 85.6%-88.3%). Diagnostic concordance by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision chapter ranged from 64.7% (95% CI, 42.0%-87.4%) for diseases of the ear and mastoid process to 96.8% (95% CI, 94.7%-98.8%) for neoplasms. Diagnostic concordance by medical specialty ranged from 77.3% (95% CI, 64.9%-89.7%) for otorhinolaryngology to 96.0% (92.1%-99.8%) for psychiatry. Specialty care was found to be significantly more likely than primary care to result in video telemedicine diagnoses concordant with a subsequent in-person visit (odds ratio, 1.69; 95% CI, 1.24-2.30; P < .001). Conclusions and Relevance: This diagnostic study of video telemedicine visits yielded a high degree of diagnostic concordance compared with in-person visits for most new clinical concerns. Some specific clinical circumstances over video telemedicine were associated with a lower diagnostic concordance, and these patients may benefit from timely in-person follow-up.

Ventricular Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy (Analysis Spanning 60 Years Of Practice): AJC Expert Panel.

Surgical myectomy remains the time-honored primary treatment for hypertrophic cardiomyopathy patients with drug refractory limiting symptoms due to LV outflow obstruction. Based on >50 years experience, surgery reliably reverses disabling heart failure by permanently abolishing mechanical outflow impedance and mitral regurgitation, with normalization of LV pressures and preserved systolic function. A consortium of 10 international currently active myectomy centers report about 11,000 operations, increasing significantly in number over the most recent 15 years. Performed in experienced multidisciplinary institutions, perioperative mortality for myectomy has declined to 0.6%, becoming one of the safest currently performed open-heart procedures. Extended myectomy relieves symptoms in >90% of patients by ≥ 1 NYHA functional class, returning most to normal daily activity, and also with a long-term survival benefit; concomitant Cox-Maze procedure can reduce the number of atrial fibrillation episodes. Surgery, preferably performed in high volume clinical environments, continues to flourish as a guideline-based and preferred high benefit: low treatment risk option for adults and children with drug refractory disabling symptoms from obstruction, despite prior challenges: higher operative mortality/skepticism in 1960s/1970s; dual-chamber pacing in 1990s, alcohol ablation in 2000s, and now introduction of novel negative inotropic drugs potentially useful for symptom management.

Cardiopulmonary exercise test in patients with obstructive hypertrophic cardiomyopathy.

OBJECTIVE: The study objective was to analyze performance on cardiopulmonary exercise testing and its prognostic value in patients with obstructive hypertrophic cardiomyopathy undergoing septal myectomy. METHODS: We reviewed patients with obstructive hypertrophic cardiomyopathy who had cardiopulmonary exercise testing before septal myectomy from 2005 to 2016. Causes of functional impairment and their impact on survival were analyzed. RESULTS: A total of 752 patients had cardiopulmonary exercise testing at a median of 16 days (interquartile range, 2-56) before myectomy. The median exercise time was 6.6 (5.3-8.0) minutes. Functional aerobic capacity was 64% (53%-75%) of predicted, and metabolic equivalent of task was 5.2 (4.1-6.4). The peak oxygen consumption was 18.0 (14.2-21.9) mL/kg/min, which was 60% (49%-72%) of the predicted value. The primary causes for low peak oxygen consumption were impaired cardiac output (73.7%), limited heart rate reserve (52.0%), and obesity (48.2%). Resting outflow tract gradient correlated poorly to peak oxygen consumption, but the use of beta-blockers was associated with reduced peak oxygen consumption. During a median (interquartile range) of 9.0 (6.8-11.7) years of follow-up, the estimated 5- and 10-year survivals were 97% and 91%, respectively. Greater adjusted peak oxygen consumption (hazard ratio, 0.98; P = .011) and abnormal pulse oxygen increase (hazard ratio, 0.44; P = .003) were independently associated with better long-term survival after myectomy. CONCLUSIONS: Among patients with hypertrophic cardiomyopathy undergoing septal myectomy, functional capacity is severely impaired despite receiving optimal medical treatment. We identified risk factors of reduced long-term survival from preoperative cardiopulmonary exercise testing that may aid risk stratification in patients undergoing septal myectomy.

Survival Following Alcohol Septal Ablation or Septal Myectomy for Patients With Obstructive Hypertrophic Cardiomyopathy.

BACKGROUND: There is little information regarding long-term mortality comparing the 2 most common procedures for septal reduction for obstructive hypertrophic cardiomyopathy (HCM), alcohol septal ablation (ASA), and septal myectomy. OBJECTIVES: This study sought to compare the long-term mortality of patients with obstructive HCM following septal myectomy or ASA. METHODS: We evaluated outcomes of 3,859 patients who underwent ASA or septal myectomy in 3 specialized HCM centers. All-cause mortality was the primary endpoint of the study. RESULTS: In the study cohort, 585 (15.2%) patients underwent ASA, and 3,274 (84.8%) underwent septal myectomy. Patients undergoing ASA were significantly older (median age: 63.0 years [IQR: 52.7-72.8 years] vs 53.7 years [IQR: 44.9-62.8 years]; P < 0.001) and had smaller septal thickness (19.0 mm [IQR: 17.0-22.0 mm] vs 20.0 mm [IQR: 17.0-23.0 mm]; P = 0.007). Patients undergoing ASA also had more comorbidities, including renal failure, diabetes, hypertension, and coronary artery disease. There were 4 (0.7%) early deaths in the ASA group and 9 (0.3%) in the myectomy group. Over a median follow-up of 6.4 years (IQR: 3.6-10.2 years), the 10-year all-cause mortality rate was 26.1% in the ASA group and 8.2% in the myectomy group. After adjustment for age, sex, and comorbidities, the mortality remained greater in patients having septal reduction by ASA (HR: 1.68; 95% CI: 1.29-2.19; P < 0.001). CONCLUSIONS: In patients with obstructive hypertrophic cardiomyopathy, ASA is associated with increased long-term all-cause mortality compared with septal myectomy. This impact on survival is independent of other known factors but may be influenced by unmeasured confounding patient characteristics.

Transapical Ventricular Remodeling for Hypertrophic Cardiomyopathy With Systolic Cavity Obliteration.

BACKGROUND: Some patients with hypertrophic cardiomyopathy (HCM) present with reduced left ventricular (LV) stroke volume and elongated systolic cavity obliteration due to symmetric LV hypertrophy. In this report, we detail our experience with transapical septal myectomy to enlarge the LV volume and to relieve cavity obliteration in this unique subgroup of patients with HCM. METHODS: We analyzed 38 patients with HCM who had extended symmetric LV hypertrophy and underwent transapical septal myectomy to enlarge the LV cavity from February 2001 to May 2021. RESULTS: At the time of evaluation for operation, 84.2% (n = 32) of the patients were in New York Heart Association class III/IV. The peak oxygen consumption was 51.5% (44.0%-58.0%) of the normal predicted values on the preoperative exercise stress test (n = 16). Preoperative left atrial sizes in this cohort were enlarged (left atrial volume index, 39.0 [33.5-51.5] mL/m2), despite only 4 patients with moderate or greater mitral valve regurgitation. All patients underwent transapical septal myectomy to enlarge the LV cavity size. There was no postoperative (within 30 days) death. During a median (interquartile range) follow-up of 3.4 (0.7-6.9) years, the estimated survival rates were 100%, 92%, and 87% at 1, 3, and 5 years, respectively. Follow-up surveys suggested that 16 of the 17 contacted patients experienced improvement in their heart function after the procedure. CONCLUSIONS: Transapical myectomy to enlarge LV cavity volume can be performed safely with good early survival and functional results. This procedure is an important alternative to cardiac transplantation for HCM patients with systolic cavity obliteration and progressive heart failure.

Surgical Management of Hypertrophic Cardiomyopathy Complicated by Infective Endocarditis.

BACKGROUND: Infective endocarditis is a serious complication in hypertrophic cardiomyopathy. Cardiac surgery is often necessary, however, literature assessing surgical outcomes is limited. METHODS: From December 1995 to September 2018, 43 patients with a history of hypertrophic cardiomyopathy and native valve infective endocarditis underwent cardiac surgery at our institution. Relevant data were abstracted from medical records and analyzed. RESULTS: Median age was 57 years (interquartile range, 45 to 67); 81% (n = 35) were male. Infective endocarditis was active in 21% of patients (n = 9) at the time of surgery; of these, the suspected origin of infection was orodental in 19% (n = 8). Significant mitral valve regurgitation was detected in 54% of patients (n = 23), and aortic valve regurgitation in 7% (n = 3). Septal myectomy was performed in 95% of patients (n = 41), with concomitant valve surgery in 58% (n = 25), including prosthetic replacement in 28% (n = 12). Two patients underwent double valve replacement without septal myectomy. Outflow gradients improved from a median 67 mm Hg (interquartile range, 34 to 97 mm Hg) to 9 mm Hg (interquartile range, 6 to 22 mm Hg). One inhospital death occurred because of uncontrollable pulmonary edema. As of last follow-up, 7 patients required reoperation, and the 5-year and 10-year cumulative incidences were 11% and 26%, respectively. Ten deaths occurred; overall survival probability at 5 and 10 years was 94% and 78%, respectively. CONCLUSIONS: Valvular complications of infective endocarditis add complexity to surgical management of hypertrophic cardiomyopathy. There is an increased need for concomitant valve repairs, prosthetic replacements, and reoperation. These data underscore the need for recognition of infection, especially after oral procedures, which preceded the majority of the active infective endocarditis cases.

Surgical management of diastolic heart failure after septal myectomy for obstructive hypertrophic cardiomyopathy.

OBJECTIVE: Some patients with obstructive hypertrophic cardiomyopathy may remain limited after surgical relief of the subaortic obstruction. In this report, we describe experience in surgical management of patients with advanced diastolic heart failure symptoms after adequate transaortic septal myectomy for obstructive hypertrophic cardiomyopathy. METHODS: We identified adult patients who presented with heart failure symptoms after previous transaortic septal myectomy for obstructive hypertrophic cardiomyopathy and underwent repeat sternotomy for transapical myectomy to enlarge a small left ventricular cavity. Functional recovery after hospital dismissal was assessed through a questionnaire-based survey. RESULTS: Six patients with previous septal myectomy presented with New York Heart Association functional class III symptoms. Preoperative transthoracic Doppler echocardiography confirmed adequate relief of subaortic outflow tract obstruction with only trivial or mild mitral valve regurgitation; left atrial volume index was increased at 46 mL/m2 (range, 44-47 mL/m2). Following transapical myectomy, the left ventricular diameter was enlarged from 23 mm (range, 21-27 mm) to 29 mm (range, 27-31 mm) at end-systole and from 40 mm (range, 38-42 mm) to 43 mm (range, 42-50 mm) at end-diastole. All the patients were alive after a median follow-up of 0.6 years (range, 0.4-3.5 years), and 5 patients responded to a postoperative survey and indicated improvement in their heart condition compared with functional status before the repeat myectomy. CONCLUSIONS: Patients with diastolic heart failure after septal myectomy for obstructive hypertrophic cardiomyopathy may present with systolic cavity obliteration due to excessive myocardial hypertrophy. Repeat transapical myectomy can enlarge the left ventricular chamber and augment the diastolic volume, which results in improved physical capacity and patient-perceived functional status.

Safety of Bariatric Surgery in Obese Patients With Hypertrophic Cardiomyopathy.

Obesity is an independent risk factor for heart failure in patients with hypertrophic cardiomyopathy (HC). In this study, we examined national trends and early outcomes of bariatric surgery for obesity in patients with HC. Using the weighted discharge data from the National Inpatient Sample, we identified adult patients with HC who underwent elective bariatric surgery for obesity between 2011 and 2017. A total of 443 obese patients with HC were identified, and 42% (n = 185) had obstructive HC. The annual number of patients increased from 18 in 2011 to 130 in 2017. Overall, the median (interquartile range) age was 50 (43 to 57) years, and 85 patients (19%) were 60 years or older. Approximately 20% (n = 90) of the patients had heart failure at the time of operation. Atrial fibrillation was present in 83 patients (19%), and 22% (n = 95) of the cohort had a pacemaker or automatic cardiac defibrillator implanted before the operation. Laparoscopic sleeve gastrectomy (72%, n = 318) and laparoscopic Roux-en-Y gastric bypass (25%, n = 110) were the most commonly performed bariatric procedures. Overall, patients stayed in the hospital for a median (interquartile range) of 2 (1 to 2) days. During the hospital stay, there were no deaths, myocardial infarctions, or documented episodes of thromboembolism. In conclusion, bariatric surgery in patients with HC is performed more frequently in recent years and is safe and associated with few perioperative complications. Because of the impact of obesity on long-term survival, clinicians should strongly consider bariatric surgery for obese HC patients who do not respond to conservative weight loss measures.

Is there referral bias in outcomes of septal myectomy for hypertrophic cardiomyopathy?

PURPOSE: To determine the potential impact of referral bias on short- and long-term outcomes following septal myectomy for hypertrophic cardiomyopathy. METHODS: We reviewed 2303 adult patients who underwent transaortic septal myectomy for obstructive hypertrophic cardiomyopathy from January 1993 to April 2016. Patients were divided into 3 groups according to their permanent address: local (state) residents (n = 324), regional (surrounding 5 states) patients (n = 515), and national (outside 5 states) patients (n = 1464). RESULTS: Patient groups were similar for age, sex, preoperative New York Heart Association class, and left ventricular ejection fraction. Local patients had increased prevalence of diabetes mellitus (13%, 11%, 8%; P = .006), coronary artery disease (25%, 21%, 19%; P = .031), severe chronic lung disease (2.3%, 1.9%, 0.4%; P < .001), and atrial fibrillation (24%, 18%, 19%; P = .045) when compared with regional and national patients. Echocardiographic features did not differ between the 3 groups, including prevalence of moderate or greater mitral regurgitation (59%, 61%, 56%; P = .161). Local and regional patients were more likely to undergo concomitant procedures than national patients (P < .001). Mitral valve surgery was performed in 9.6% of the patients, more commonly in local and regional patients (12%, 12%, 8%; P = .018). There were 11 operative deaths (0.5%), and early mortality was similar among the groups. Geographic origin did not impact overall late survival. CONCLUSIONS: Compared with distant referrals, local patients who undergo septal myectomy at our institution have more comorbid conditions, and require more concomitant surgical procedures. Despite these differences, referral patterns did not impact early or late outcomes following transaortic septal myectomy.