Survival Differences in Women and Men After Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy

Natural History of Hypertrophic Cardiomyopathy in Korea: A Nationwide Population-Based Retrospective Cohort Study

BACKGROUND

There are few long-term large-scale epidemiologic studies on hypertrophic cardiomyopathy (HCM; 10th revision of the International Statistical Classification of Diseases and Related Health Problems codes: I42.1, I42.2). This analysis used the Korean National Health Insurance Service (KNHIS) data between 2006 and 2017 to evaluate the natural history of HCM over a decade.

METHODS

KNHIS data and death statistics were evaluated according to age, sex, socioeconomic position, and comorbidities. Survival rates (SRs) and adjusted hazard ratio (HR) were compared with death data of the Korean population from 2006 through 2018.

RESULTS

The mean age was 47.3 ± 14.9 years in males and 57.5 ± 15.4 years in females (P < 0.001). The male proportion was 58.9%. The most common cause of death was diseases of the circulatory system. The 10-year SR of HCM was higher in males (75.9% vs. 62.5%, P < 0.001). The adjusted HR for different age groups was significantly high in most age group: 3.67 (95% confidence interval [CI], 2.65-5.10) for 0-9 years, and it gradually increased from the 30s to the 80s group (1.39 [95% CI, 1.05-1.83] for 30-39 years and 48.2 [95% CI, 37.0-62.7] for those older than 80 years). The adjusted HR was 1.12 (95% CI, 1.07-1.17) for males, 1.40 (95% CI, 1.33-1.48) for the lower income level, and 1.18 (95% CI, 1.12-1.25) for the medium income level. In patients with comorbidities, the adjusted HRs were 1.23 (95% CI, 1.16-1.30) for diabetes, 1.45 (95% CI, 1.30-1.62) for myocardial infarction, 1.63 (95% CI, 1.52-1.76) for atrial fibrillation, 1.83 (95% CI, 1.68-1.99) for ischemic stroke, 1.66 (95% CI, 1.31-2.10) for hemorrhagic stroke, 2.42 (95% CI, 2.16-2.70) for chronic kidney disease, and 3.18 (95% CI, 2.87-3.52) for malignant neoplasm.

CONCLUSION

HCM in Korea showed a higher prevalence and incidence in males. The 10-year SR of HCM was approximately 70% and lower in females than that in males. The risk of death from HCM increased with age and was significantly higher in males, individuals with low income levels, and patients with various comorbidities. These findings should be considered for the long-term management and allocation of healthcare resources for patients with HCM.

Phenotype-Based Classification of Obstructive Hypertrophic Cardiomyopathy Undergoing Myectomy

This study partitioned variables derived from clinical and pathological information in patients who received septal reduction therapy to identify obstructive hypertrophic cardiomyopathy subtypes. Subtype 1 was characterized by a high percentage of sarcomere mutation carriers and the highest interventricular septal thickness. Subtype 2 was featured by left atrial enlargement and a high percentage of patients with atrial fibrillation. Subtype 3 was characterized by a high left ventricular outflow tract gradient, serious inflammatory cell infiltration, and a high incidence of postoperative adverse events. This finding has been well replicated in 2 validation cohorts with short- and long-term follow-up.

Understanding Sex Differences in Hypertrophic Cardiomyopathy Surgery: Insights From a Decade-Long Cohort Study From China

BACKGROUND

Sex differences in patients with hypertrophic cardiomyopathy have been elaborated by many studies. However, large studies of the association of patient sex with outcomes after surgical myectomy are scarce. This study evaluated sex disparities in a large Chinese cohort undergoing hypertrophic cardiomyopathy surgery.

METHODS

The cohort encompassed 1613 patients, including 627 (38.9%) women who underwent septal myectomy between 2009 and 2018.

RESULTS

At the time of surgery, women were 6 years older and had 1 year longer disease onset-to-surgery delay than men. They were more frequently in New York Heart Association class III/IV and had more severe left ventricular outflow tract obstruction. Compared with men, women had a notably higher left ventricular wall thickness index and a lower extent of late gadolinium enhancement. Women also had more mutations in MYH7 and fewer in MYBPC3. Postoperatively, women had a higher operative mortality rate (1.3% versus 0.1%, P=0.006). The follow-up results showed no significant difference between the sexes in all-cause death (hazard ratio [HR], 0.67 [95% CI, 0.38-1.18]; P=0.166). A U-shaped association was observed between age and death in the overall population. However, women exhibited this association more obviously at age ≥55 years and men at <35 years. Moreover, women also had a higher risk of cardiovascular rehospitalization after surgery (HR, 1.40 [95% CI, 1.03-1.89]; P=0.030).

CONCLUSIONS

In patients with obstructive hypertrophic cardiomyopathy, women had a similar fatal outcome but a worse nonfatal outcome than men after surgery. Measures improving quality of life may further enhance the event-free survival of female patients. Close monitoring and follow-up are warranted, especially in younger men and older women.

Demographic-Based Personalized Left Ventricular Hypertrophy Thresholds for Hypertrophic Cardiomyopathy Diagnosis

BACKGROUND

Hypertrophic cardiomyopathy (HCM) is a leading cause of sudden cardiac death. Current diagnosis emphasizes the detection of left ventricular hypertrophy (LVH) using a fixed threshold of ≥15-mm maximum wall thickness (MWT). This study proposes a method that considers individual demographics to adjust LVH thresholds as an alternative to a 1-size-fits-all approach.

METHODS

Left ventricular MWT was measured in 3 cohorts: a Reference Cohort of healthy adults (n = 5,067, no comorbidities), a Population Cohort (n = 43,239, with comorbidities), and an HCM Cohort from 6 international centers (n = 2,424). Measurement used cardiovascular magnetic resonance (CMR) and a validated artificial intelligence algorithm. The Reference Cohort was used to developed demographically adjusted LVH thresholds, and individualized z-scores based on age, sex, and body surface area (BSA), which were used to explore the other cohorts.

RESULTS

The traditional ≥15-mm threshold classified 4.3% (n = 1,854) of the Population Cohort as hypertrophic, with a significant sex skew (89% male). Demographic-adjusted LVH thresholds (range: 10-17 mm) reduced ascertainment to 2.2% (n = 945), reducing the sex skew (56% male). Similar reductions in bias with height, weight, and age also occurred. The HCM cohort was found to have a 2:1 male-to-female ratio. A significant proportion of patients received diagnoses of HCM despite having MWT below the traditional LVH threshold (<15 mm): 27% of female individuals and 18% of male individuals. Using demographic-adjusted LVH thresholds reduced these proportions to 7% of female individuals and 15% of male individuals (P < 0.0001). Female patients had lower absolute MWT (18 mm vs 19 mm; P < 0.001) but higher MWT z-scores (5.1 vs 4.5; P = 0.05).

CONCLUSIONS

Age, sex, and body size influence the normal heart MWT. Using a fixed LVH threshold ≥15 mm biases LVH ascertainment in both population and HCM cohorts. A demographic-adjusted approach for LVH improves ascertainment and diagnostic accuracy.

Sex differences in the prevalence and survival of pulmonary hypertension in obstructive hypertrophic cardiomyopathy following septal myectomy

Background

Pulmonary hypertension (PH) and female have been linked to a worse survival in patients with obstructive hypertrophic cardiomyopathy (oHCM). However, female patients with PH exhibited a better prognosis than males. Herein, we investigated sex differences in the prevalence and survival of pH in oHCM following septal myectomy.

Methods

We consecutively enrolled 1491 patients diagnosed with oHCM. PH was defined as a pulmonary artery systolic pressure (PASP) > 36 mm Hg.

Results

Females were older, more likely to experience chest pain and NYHA class III/IV symptoms, and had a higher prevalence of PH (37.6 % vs. 19.9 %, p < 0.001) than males. Multivariable analysis showed that female was an independent risk for PH (OR 2.3, 95 % CI: 1.70-3.11, p < 0.001) though the PASP was comparable between males and females (44.93 ± 10.87 vs. 44.74 ± 9.72 mm Hg, p = 0.856). Over a median follow-up of 36 months [IQR 23.5-52.5 months), 28 deaths and 189 composite endpoints were observed. Kaplan-Meier analysis showed a higher cumulative incidence of death (p = 0.015) and composite endpoints (p < 0.001) in patients with PH, and Cox regression analysis revealed that PH (HR 1.78, 95 % CI: 1.30-2.45, p < 0.001) and female (HR 1.39, 95 % CI: 1.02-1.90, p = 0.038) were independently associated with composite endpoints. However, no significant survival differences were found between males and females within the PH subgroup.

Conclusions

Female was independently associated with higher prevalence but not severity of PH. Although PH and female were independently associated with worse survival, no survival difference was found between males and females in the PH subgroup.

Preoperative D-dimer and outcomes in obstructive hypertrophic cardiomyopathy after myectomy

BACKGROUND

The prognostic significance of D-dimer in patients with hypertrophic cardiomyopathy undergoing septal myectomy has not been well established.

METHODS

We retrospectively analyzed D-dimer levels in 728 patients who underwent septal myectomy at our hospital between 2009 and 2018. Baseline D-dimer levels were categorized into tertiles (<0.21, 0.21-0.3, ≥0.3 mg/L) The primary and secondary endpoints were all-cause mortality and cardiovascular mortality, respectively. Cox regression and competing risk models were used to evaluate risk factors for all-cause and cardiovascular mortality, respectively.

RESULTS

Higher D-dimer levels were associated with older age, female sex, more severe mitral regurgitation, and elevated N-terminal pro B-type natriuretic peptide levels (P < 0.05). Over a median follow-up of 4.2 years, 31 (4.3 %) patients reached the primary endpoint; 23 deaths were attributed to cardiovascular causes. The optimal cutoff D-dimer level for predicting 5-year mortality was 0.29 mg/L. After adjusting for covariates, D-dimer levels of >0.29 mg/L were significantly associated with an increased risk of all-cause mortality (hazard ratio [HR], 3.12; 95 % confidence interval [CI], 1.42-6.86; p = 0.005) and cardiovascular mortality (HR, 3.29; 95 % CI, 1.12-9.62; p = 0.030). Body mass index and left atrial diameter were also independent predictors of both all-cause mortality (HR, 1.12; p = 0.026, and HR, 1.08; p = 0.006, respectively) and cardiovascular mortality (HR, 1.12; p = 0.043, and HR, 1.11; p = 0.004, respectively). The inclusion of D-dimer levels of >0.29 mg/L improved the net reclassification index for all-cause mortality (p = 0.016).

CONCLUSION

D-dimer is a robust predictor of mid-to-long-term all-cause and cardiovascular mortality in patients undergoing septal myectomy.

Gender and age predict advanced heart failure in gene-negative patients with hypertrophic cardiomyopathy

BACKGROUND

Patients with hypertrophic cardiomyopathy (HCM) may develop concomitant advanced heart failure (HF). However, there is limited data on the clinical outcomes of HCM patients without sarcomere gene mutations who have advanced HF.

OBJECTIVES

To identify prognostic factors for advanced HF in gene-negative patients within a large HCM cohort.

METHODS

A total of 1529 unrelated patients with HCM were enrolled between 1999 and 2018, and followed throughout the study period. All patients underwent genotyping through whole exome or panel sequencing. From this cohort, 735 patients without mutations were studied. We assessed the effects of family history, clinical findings, and echocardiographic parameters on the development of advanced HF. Multivariable Cox proportional hazards regression analysis was conducted to identify risk factors associated with advanced HF.

RESULTS

Of the 735 gene-negative patients studied, the mean age was 52.5±13.2 years, 69.5% were male, and the mean follow-up duration was 3.2±2.3 years. During this period, 97 patients (13.2%) developed advanced HF. Using multivariable analysis, we identified significant risk factors for advanced HF: female gender (adjusted hazard ratio [HR] 2.499, 95% confidence interval [CI] 1.531-4.081, P<0.001) and older age at enrollment (adjusted HR 1.298, 95% CI 1.00-1.682, P=0.049). These findings suggest that female patients and those enrolled at an older age are at a higher risk for developing advanced HF.

CONCLUSION

Female gender and older age may predict a higher risk of advanced HF in gene-negative patients with HCM. Early detection and proactive treatment are crucial for managing and preventing complications in these patients.

Sex-Associated Differences in Clinical Outcomes After Septal Reduction Therapies in Hypertrophic Cardiomyopathy

OBJECTIVE

To evaluate sex-associated differences in the short- and long-term outcomes of patients with hypertrophic cardiomyopathy (HCM) undergoing septal myectomy and alcohol septal ablation.

METHODS

This retrospective cohort study used electronic health record data from the TriNetX research database. International Classification of Diseases, Ninth Revision and Tenth Revision diagnosis and procedure codes were used to identify patients with HCM who underwent septal myectomy and alcohol septal ablation in the United States between January 2002 and March 2023. The outcomes were long-term mortality and postprocedural complications (<30 days), including death, stroke, major bleeding, and renal failure. Multivariable adjusted Cox models were used to assess the association of outcomes by sex, taking female patients as reference.

RESULTS

Of 11,680 adults (32.0% female; median age, 63 [interquartile range, 54 to 71] years), 1916 (16.4%) and 9764 (83.6%) underwent septal myectomy and alcohol septal ablation, respectively. For those who underwent septal myectomy, sex was not associated with short-term (adjusted hazard ratio [HRadj], 1.57 [0.64 to 3.87]) and long-term (HRadj, 1.05 [0.87 to 1.26]) mortality. Male patients had a higher risk of acute renal failure compared with female patients after septal myectomy (HRadj, 1.69 [1.33 to 2.15]). Of those who underwent alcohol septal ablation, male patients (HRadj, 1.07 [0.99 to 1.16]) had a similar risk of long-term mortality to that of female patients. Compared with female patients, the risk of acute renal failure was higher in male patients (HRadj, 1.23 [1.02 to 1.48]) after alcohol septal ablation.

CONCLUSION

This nationwide study found that the risk of short- and long-term mortality was similar for male and female patients undergoing septal myectomy and alcohol septal ablation for HCM. The sex-based differences in the clinical presentation should not prevent consideration of septal reduction therapies.

Long-Term Outcomes After Septal Reduction Therapies in Obstructive Hypertrophic Cardiomyopathy: Insights From the SHARE Registry

BACKGROUND

Septal reduction therapy (SRT) provides substantial symptomatic improvement in patients with obstructive hypertrophic cardiomyopathy (HCM). However, long-term disease course after SRT and predictors of adverse outcomes have not been systematically examined.

METHODS

Data from 13 high clinical volume HCM centers from the international SHARE (Sarcomeric Human Cardiomyopathy Registry) were analyzed. Patients were followed from the time of SRT until last follow-up or occurrence of heart failure (HF) composite outcome (cardiac transplantation, implantation of a left ventricular assist device, left ventricular ejection fraction <35%, development of New York Heart Association class III or IV symptoms), ventricular arrhythmias composite outcome (sudden cardiac death, resuscitated cardiac arrest, or appropriate implantable cardioverter defibrillator therapy), or HCM-related death. Cox proportional hazards models were used to identify predictors of outcome.

RESULTS

Of the 10 225 patients in SHARE, 1832 (18%; 968 [53%] male) underwent SRT, including 455 (25%) with alcohol septal ablation and 1377 (75%) with septal myectomy. The periprocedural 30-day mortality rate was 0.4% (8 of 1832) and 1499 of 1565 (92%) had a maximal left ventricular outflow tract gradient <50 mm Hg at 1 year. After 6.8 years (range, 3.4-9.8 years; 12 565 person-years) from SRT, 77 (4%) experienced HCM-related death (0.6% per year), 236 (13%) a composite HF outcome (1.9% per year), and 87 (5%) a composite ventricular arrhythmia outcome (0.7% per year). Among adults, older age at SRT was associated with a higher incidence of HCM death (hazard ratio, 1.22 [95 CI, 1.1-1.3]; P<0.01) and the HF composite (hazard ratio, 1.14 [95 CI, 1.1-1.2] per 5-year increase; P<0.01) in a multivariable model. Female patients also had a higher risk of the HF composite after SRT (hazard ratio, 1.4 [95 CI, 1.1-1.8]; P<0.01). De novo atrial fibrillation occurred after SRT in 387 patients (21%). Among pediatric patients followed for a median of 13 years after SRT, 26 of 343 (16%) developed the HF composite outcome, despite 96% being free of recurrent left ventricular outflow tract obstruction.

CONCLUSIONS

Successful short- and long-term relief of outflow tract obstruction was observed in experienced multidisciplinary HCM centers. A subset of patients progressed to develop HF, but event-free survival at 10 years was 83% and ventricular arrhythmias were rare. Older age, female sex, and SRT during childhood were associated with a greater risk of developing HF.

Clinical Outcomes of Concomitant Coronary Artery Bypass Grafting During Ventricular Septal Myectomy

BACKGROUND

The clinical characteristics and survival outcomes of patients who underwent concomitant coronary artery bypass grafting during septal myectomy have not been well studied.

METHODS AND RESULTS

We reviewed patients who underwent both septal myectomy and coronary artery bypass grafting from 2009 to 2020. Causes of concomitant grafting and their impact on survival were analyzed. The median follow-up period was 5.1 years. A total of 320 patients underwent both grafting and myectomy. Of these, 69.7% and 28.1% underwent grafting attributed to atherosclerotic coronary artery disease and myocardial bridging, respectively. Patients who underwent grafting for coronary artery disease tended to be older, had a longer bypass time, and required more grafts compared with patients undergoing procedures because of myocardial bridging (all P<0.05). Postoperatively, the left ventricular outflow gradient significantly decreased from 85.4 mm Hg to 12.8 mm Hg (P<0.001) without perioperative death. The cumulative survival rates were 96.2% and 97.6% at 5 years in the coronary artery disease and myocardial bridging groups, respectively, and they were comparable to that of general myectomy cohort (hazard ratio [HR], 1.06 [95% CI, 0.47-2.36], P=0.895 and HR 0.75 [95% CI, 0.23-2.46], P=0.636, respectively). Sudden death accounted for 45.5% (5 of 11) of postoperative mortality. Analysis of composite end point events showed decreased morbidity with at least one arterial graft in the overall cohort (HR, 0.47 [95% CI, 0.23-0.94], P=0.034).

CONCLUSIONS

Concomitant grafting in septal myectomy was found to be a safe procedure. Patients who underwent such surgery experienced favorable postoperative outcomes comparable to those who underwent septal myectomy alone, with a 5-year survival rate of >95% and improved functional class of >90%.

Clinical features and postoperative outcomes in elderly patients undergoing septal myectomy for hypertrophic cardiomyopathy

OBJECTIVES

Surgical septal reduction is sometimes avoided in older adults due to anticipated high operative risk. The study objectives were to compare the clinical and echocardiographic characteristics of young and older patients undergoing septal myectomy for obstructive hypertrophic cardiomyopathy and assess differences in early and late postoperative outcomes.

METHODS

A total of 2663 patients with obstructive hypertrophic cardiomyopathy underwent transaortic septal myectomy between 2000 and 2021 and were categorized by age: 18 to 64 years, 65 to 74 years, and 75 years or more.

RESULTS

Median age at the time of surgery increased over the study interval. Female sex (P < .001), hypertension P < .001), and diabetes (P = .004) were more prevalent in older patients, but extent of functional limitation (New York Heart Association) was similar (P = .092). Elderly patients had thinner septal and posterior walls (P < .001, P = .006) and less prominent asymmetry (P < .001). They are less likely to have positive genetic testing. Hospital mortality was 0.2%, 0.5%, and 1.3% in patients aged less than 65 years, 65 to 74 years, and 75 years or more, respectively (P = .06), and 5-year survivals were 97%, 93%, and 91%, respectively. Septal-to-posterior wall thickness ratio significantly correlated with increased mortality in patients aged more than 65 years, but not in patients aged less than 65 years (P = .92). Most of the patients reported improved quality of life after myectomy.

CONCLUSIONS

Clinical characteristics of obstructive hypertrophic cardiomyopathy in older patients differ from those in younger patients. More symmetric but less extensive ventricular hypertrophy and less positive genetic testing suggests that hypertrophic cardiomyopathy has distinct clinical and morphological variants in the elderly. Septal myectomy is safe in older patients, but the presence of left ventricular wall asymmetry portends a poorer prognosis.

Sex Disparities in the Use and Outcomes of Septal Reduction Therapies for Obstructive Hypertrophic Cardiomyopathy

Background

Data are limited that examine potential sex-based disparities in the utilization and complications of septal reduction therapy (SRT) in patients with obstructive hypertrophic cardiomyopathy. Our aim was to assess the use and in-hospital outcomes of SRT, according to sex. We performed a retrospective cohort study using the 2017-2019 National Inpatient Sample database. Adult patients with obstructive hypertrophic cardiomyopathy were identified.

Methods

We assessed the use of SRT (surgical septal myectomy and alcohol septal ablation), according to sex. In those who underwent SRT, rates of in-hospital mortality, pacemaker implantation, implantable cardioverter defibrillator (ICD) implantation, ischemic stroke, major bleeding, and pericardial complication were assessed. All outcomes were compared between groups using inverse probability of treatment weighting (IPTW), adjusting for demographics, comorbidity burden, and hospital characteristics.

Results

In total, 72,680 weighted hospitalizations (median age: 67 years [range: 57-77]; 61% female patients) were included, and only 5.9% of patients underwent SRT. After IPTW adjustment, female patients were more likely to undergo SRT (adjusted risk ratio [aRR] 1.18, 95% confidence interval [95% CI] 1.03-1.36) and alcohol septal ablation (aRR 1.38, 95% CI 1.04-1.83). Likewise, female patients received pacemaker implantation more often (aRR 1.96, 95% CI 1.10-3.50) and ICD implantation (aRR 0.58, 95% CI 0.34-0.99) less frequently, compared with male patients. No differences were present in rates of surgical septal myectomy, in-hospital mortality, ischemic stroke, major bleeding, and pericardial complication between groups.

Conclusions

Our results suggest that female patients were slightly more likely to undergo SRT, especially alcohol septal ablation. In-hospital mortality and postprocedural complications were similar between the sexes, but women received more pacemaker implantation and less ICD implantation.

Sex-Related Differences in Patients With Hypertrophic Cardiomyopathy Undergoing Alcohol Septal Ablation

BACKGROUND

Previous studies have shown that women with hypertrophic obstructive cardiomyopathy (HCM) have worse long-term outcomes irrespective of intervention. However, the outcomes of patients undergoing alcohol septal ablation (ASA) based on sex have not been described. Hence, this study aimed to evaluate pressure changes and long-term mortality in patients with HCM undergoing ASA based on sex.

METHODS AND RESULTS

This is a single-center retrospective study evaluating hemodynamic changes and long-term mortality in patients with HCM treated with ASA according to sex. A total of 259 patients were included (aged 68.4±11.9 years, 62.2% women). Women had higher age and baseline pressures at the time of ASA, with a greater percent reduction in mean left atrial pressure (men versus women: 2.2% versus 15.9%, respectively; P=0.02). Women had better survival (median survival rate of men versus women: 8.6 versus 12.5 years, respectively; P=0.011). On Cox multivariable regression, predictors of mortality were age (per group change <60 years, 61-70 years, 71-80 years, and >80 years; hazard ratio [HR], 1.45 [95% CI, 1.10-1.91], P=0.008), female sex (HR, 0.59 [95% CI, 0.35-0.99], P=0.048), chronic kidney disease (HR, 1.88 [95% CI, 1.06-3.33], P=0.031), and left ventricular outflow tract gradient reduction ≤86% (HR, 1.91 [95% CI, 1.14-3.19], P=0.014).

CONCLUSIONS

Women with HCM undergoing ASA are older and have higher left-sided baseline pressures compared with men yet have better survival. Further studies exploring the mechanisms of differential outcomes according to sex in patients with HCM undergoing ASA are needed.

Impact of concomitant surgical interventions on outcomes of septal myectomy in obstructive hypertrophic cardiomyopathy

BACKGROUND

Septal myectomy (SM) is offered to symptomatic patients with obstructive hypertrophic cardiomyopathy (oHCM) despite medical therapy. Frequently, patients undergo concomitant planned or ad-hoc mitral valve replacement (MVR), aortic valve replacement (SAVR), or coronary artery bypass grafting (CABG).

OBJECTIVES

We sought to assess characteristics and outcomes of patients with oHCM undergoing concomitant surgical interventions at the time of SM.

METHODS

The National Readmission Databases were used to identify all SM admissions in the United States (2010-2019). Patients undergoing SM were stratified into: isolated SM (±MV repair), SM + CABG only, SM + MVR, SM + SAVR, and SM + MVR + SAVR. Primary outcomes were in-hospital mortality, in-hospital adverse events, and 30-day readmission.

RESULTS

12,063 encounters of patients who underwent SM were included (56.1% isolated SM, 9.0% SM + CABG only, 17.5% SM + MVR, 13.1% SM + SAVR, and 4.3% SM + MVR + SAVR). Patients who underwent isolated SM were younger (54.3 vs. 67.1 years-old, p < 0.01) and had lower overall comorbidity burden. In-hospital mortality was lowest in isolated SM, followed by CABG only, SM + SAVR, SM + MVR, and SM + SAVR+MVR groups (2.3% vs. 3.7% vs. 5.3% vs. 6.7% vs. 13.7%, p < 0.01), respectively. SM with combined surgical interventions was associated with higher adverse in-hospital events (24.3% vs. 11.1%, p < 0.01) and 30-day readmissions (16.9% vs. 10.4%, p < 0.01). MV repair performed concomitantly with SM was not associated with increased in-hospital mortality (3.9% vs. 3.4%, p = 0.72; aOR 0.99; 95% CI: 0.54-1.80, p = 0.97]) or adverse clinical events.

CONCLUSIONS

In SM for oHCM, patients undergoing concomitant surgical interventions were characteristically distinct. Aside from MV repair, concomitant interventions were associated with worse in-hospital death, adverse in-hospital events, and 30-day readmission.

Treatment Strategies for Hypertrophic Cardiomyopathy: Surgical

Septal myectomy is a well-established procedure for septal reduction in patients with obstructive hypertrophic cardiomyopathy (HCM) who have not responded to medical treatment. The surgical approach is tailored to the unique pathophysiology and septal morphology of the patient. Extended transaortic myectomy is the standard procedure for patients with isolated subaortic obstruction, the most common type of HCM. However, transapical myectomy is a useful adjunct for patients with long or midventricular obstruction and is our preferred technique for ventricular enlargement in patients with severe symptomatic diastolic heart failure because of extensive apical hypertrophy. Septal myectomy provides excellent postoperative outcomes as regards symptom relief and functional improvement, and operative morbidity and mortality rates are low in experienced centers. This article summarizes our current surgical management of patients with HCM and details operative methods and outcomes.

Contemporary Surgical Management of Hypertrophic Cardiomyopathy

More than half of symptomatic patients with hypertrophic cardiomyopathy (HCM) have left ventricular outflow tract (LVOT) obstruction. Septal reduction therapy by septal myectomy can dramatically relieve exertional dyspnea, chest pain, and presyncope in properly selected patients and is an important management pathway for many patients. The distribution and degree of hypertrophy in patients with obstructive HCM are variable and, as discussed in this review, can influence clinical manifestations of the disease and surgical management. Subaortic septal hypertrophy is the most common phenotype of obstructive HCM associated with LVOT obstruction, but midventricular obstruction and apical hypertrophy may occur in isolation or in conjunction with subaortic septal hypertrophy. In many comprehensive HCM centers, transaortic septal myectomy is the preferred method of septal reduction therapy for symptomatic patients with obstructive HCM. Early surgical approaches aimed at alleviating left LVOT obstruction were hampered by a lack of understanding of the anatomy and pathophysiology of obstructive HCM. With the advent of Doppler echocardiography and, more recently, cardiac magnetic resonance imaging, surgeons can precisely assess the location and degree of obstruction, left ventricular size and function, and morphology and function of the mitral valve. This review discusses the current understanding of the role of septal myectomy in the management of patients with HCM and details contemporary operative methods.

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.

A systematic review and meta-analysis of sex differences in clinical outcomes of hypertrophic cardiomyopathy

Background

Hypertrophic cardiomyopathy (HCM) is recognized as the most prevalent form of genetic cardiomyopathy, and recent investigations have shed light on the existence of sex disparities in terms of clinical presentation, disease progression, and outcomes.

Objectives

This study aimed to systematically review the literature and perform a meta-analysis to comprehensively compare the clinical outcomes between female and male patients with HCM.

Methods

A thorough search was conducted in databases including PubMed, Embase, Cochrane Library, and Web of Science, encompassing literature from inception until June 2023. The primary endpoints examined were: (1) all-cause mortality; (2) an arrhythmic endpoint comprising sudden cardiac death (SCD), sustained ventricular tachycardia, ventricular fibrillation, or aborted SCD; and (3) a composite endpoint incorporating either (1) or (2), in addition to hospitalization for heart failure or cardiac transplantation. Pooled estimates were derived using a random-effects meta-analysis model.

Results

The analysis encompassed a total of 29 observational studies, involving 44,677 patients diagnosed with HCM, of which 16,807 were female. Baseline characteristics revealed that the female group exhibited an advanced age [55.66 ± 0.04 years vs. 50.38 ± 0.03 years, pooled mean difference (MD) = 0.31, 95% CI: 0.22-0.40, p = 0.000, I2 = 88.89%], a higher proportion of New York Heart Association class III/IV patients [pooled odds ratio (OR) = 1.94, 95% CI: 1.55-2.43, p = 0.000, I2 = 85.92%], and a greater prevalence of left ventricular outflow tract gradient greater than or equal to 30 mmHg (pooled OR = 1.48, 95% CI: 1.27-1.73, p = 0.000, I2 = 68.88%) compared to the male group. The female group were more likely to have a positive genetic test (pooled OR = 1.27, 95% CI: 1.08-1.48, p = 0.000, I2 = 42.74%) and to carry the myosin heavy chain beta 7 mutation (pooled OR = 1.26, 95% CI: 1.04-1.54, p = 0.020, I2 = 0.00%) compared to the male group. Female sex exhibited a significant association with increased risks of all-cause mortality (pooled OR = 1.62, 95% CI: 1.38-1.89, p = 0.000, I2 = 72.78%) and the composite endpoint (pooled OR = 1.47, 95% CI: 1.20-1.79, p = 0.000, I2 = 84.96%), while no substantial difference was observed in the arrhythmic endpoint (pooled OR = 1.08, 95% CI: 0.87-1.34, p = 0.490, I2 = 55.48%).

Conclusions

The present findings suggest that female patients with HCM tend to experience poorer clinical outcomes. It is imperative to critically reevaluate disease definitions and enhance awareness to mitigate delays in the diagnosis and treatment of HCM in women, thereby fostering equitable healthcare practices.

Systematic Review Registration

https://www.crd.york.ac.uk/, PROSPERO (CRD42023431881).

Gender-Based Outcome Discrepancies in Patients Who Underwent Alcohol Septal Ablation or Septal Myectomy for Hypertrophic Obstructive Cardiomyopathy: A Systematic Review and Meta-Analysis

Clinical evidence and emerging studies suggest that the clinical heterogeneity observed in hypertrophic cardiomyopathy could be because of gender-based differences. We aimed to explore the gender-related differences pertaining to the treatment outcomes after alcohol septal ablation (ASA) and septal myectomy (SM). We searched PUBMED/MEDLINE, EMBASE, and SCOPUS to identify studies that report gender-stratified comparison of outcomes. The primary outcome of interest was short-term (within 30 days) mortality. A total of 15 studies totaling 31,907 patients (47% men and 53% women) were included. Women were found to be significantly older at the time of intervention (ASA: mean difference [MD] 7.55 years; SM: MD 4.41). In the ASA and SM treatment arms, women had a significantly higher risk of short-term all-cause mortality (ASA: risk ratio 0.48, 95% confidence interval 0.32 to 0.71, p = 0.0003; SM: risk ratio 0.63, 95% confidence interval 0.44 to 0.90, p = 0.01), more frequent permanent pacemaker implantation (ASA; p = 0.002, SM: p = 0.05), and longer in-hospital stay (ASA: MD 1.00 days, SM: MD 0.69). Among those who underwent ASA, women had a significantly higher rate of atrioventricular block. In conclusion, regardless of ASA or SM, women consistently presented at an older age and exhibited a higher risk-increased mortality rate, a greater incidence of atrioventricular block, and a higher likelihood of permanent pacemaker requirement-and longer hospital stay among women than men. This strongly emphasizes the need for a gender-specific approach to optimize care and improve treatment outcomes in hypertrophic cardiomyopathy.

Is There a Sex Difference in the Prognosis of Hypertrophic Cardiomyopathy? A Systematic Review and Meta-Analysis

Background It is still unclear whether there is a sex difference in the prognosis of patients with hypertrophic cardiomyopathy (HCM). Therefore, we performed a meta-analysis to elucidate the association between sex and adverse outcomes in patients with HCM. Methods and Results The PubMed, Cochrane Library, and Embase databases were used to search for studies on sex differences in prognosis in patients with HCM up to August 17, 2021. Summary effect sizes were calculated using a random effects model. The protocol was registered in PROSPERO (International prospective register of systematic reviews) (registration number- CRD42021262053). A total of 27 cohorts involving 42 365 patients with HCM were included. Compared with male subjects, female subjects had a higher age at onset (mean difference=5.61 [95% CI, 4.03-7.19]), a higher left ventricular ejection fraction (standard mean difference=0.09 [95% CI, 0.02-0.15]) and a higher left ventricular outflow tract gradient (standard mean difference=0.23 [95% CI, 0.18-0.29]). The results showed that compared with male subjects with HCM, female subjects had higher risks of HCM-related events (risk ratio [RR]=1.61 [95% CI, 1.33-1.94], I2=49%), major cardiovascular events (RR=3.59 [95% CI, 2.26-5.71], I2=0%), HCM-related death (RR=1.57 [95% CI, 1.34-1.82], I2=0%), cardiovascular death (RR=1.55 [95% CI, 1.05-2.28], I2=58%), noncardiovascular death (RR=1.77 [95% CI, 1.46-2.13], I2=0%) and all-cause mortality (RR=1.43 [95% CI, 1.09-1.87], I2=95%), but not atrial fibrillation (RR=1.13 [95% CI, 0.95-1.35], I2=5%), ventricular arrhythmia (RR=0.88 [95% CI, 0.71-1.10], I2=0%), sudden cardiac death (RR=1.04 [95% CI, 0.75-1.42], I2=38%) or composite end point (RR=1.24 [95% CI, 0.96-1.60], I2=85%). Conclusions Based on current evidence, our results show significant sex-specific differences in the prognosis of HCM. Future guidelines may emphasize the use of a sex-specific risk assessment for the diagnosis and management of HCM.

Impact of Race and Ethnicity on Use and Outcomes of Septal Reduction Therapies for Obstructive Hypertrophic Cardiomyopathy

Background Information on impact of race and ethnicity on use and early outcomes of septal reduction therapies (SRTs) for obstructive hypertrophic obstructive cardiomyopathy are limited. Methods and Results Using the National Inpatient Sample from January 2012 through December 2019, we identified all adult admissions with a primary diagnosis of obstructive hypertrophic cardiomyopathy and those undergoing SRT. Predictors of receiving SRT and outcomes including in-hospital mortality, complications, and resource use were evaluated in racial and ethnic groups. Among a total of 18 895 adult admissions with obstructive hypertrophic cardiomyopathy, SRT was performed in 7255 (38.4%) admissions. Septal myectomy was performed in 4930 (26.1%), while alcohol septal ablation was performed in 2325 (12.3%). In adjusted analysis, Black patient (versus White patient adjusted odds ratio, 0.65 [95% CI, 0.57-0.73]; P<0.001) and Hispanic patient admissions (versus White adjusted odds ratio, 0.78 [95% CI, 0.66-0.92]; P=0.003) were less likely to receive SRT. Among admissions undergoing SRT, in-hospital mortality was significantly higher for Hispanic (adjusted odds ratio, 3.38 [95% CI, 1.81-6.30], P<0.001) and other racial and ethnic groups (adjusted odds ratio 2.02 [95% CI, 1.00-4.11]; P=0.05) compared with White patient admissions, whereas Black patient admissions had comparable mortality. Black, Hispanic, and other ethnic group patients had higher rates of SRT complications and more frequent dismissals to acute care facilities. Conclusions Among obstructive hypertrophic cardiomyopathy hospitalizations, minoritized racial groups were less likely to receive SRT. Importantly, hospitalizations of Hispanic and other ethnic patients undergoing SRT had significantly higher in-hospital mortality and complication rates. Further studies with granular echocardiographic information to assess indications for SRT are needed to better understand these differences.

Posterior Wall Thickness Associates With Survival Following Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy

BACKGROUND

The left ventricular (LV) posterior wall thickness (PWT) is a predictor of sudden cardiac death in pediatric patients with hypertrophic cardiomyopathy (HCM), but the prognostic importance of PWT in adults has not been examined.

OBJECTIVES

The goal of this study was to evaluate the association of LV PWT with late survival in adult patients undergoing septal myectomy for obstructive HCM.

METHODS

This single-center study reviewed 2,418 patients who underwent transaortic septal myectomy for obstructive HCM.

RESULTS

The median preoperative PWT was 13 (IQR: 11-15) mm. Patients with PWT >13 mm tended to have systemic hypertension (55.4% vs 49.1%; P = 0.002) and a larger body mass index (median: 30.8 [IQR: 27.1-35.1] kg/m² vs 29.6 [IQR: 26.1-33.9] kg/m²; P < 0.001). Preoperatively, PWT >13 mm was associated with increased septal thickness (median: 21 [IQR: 18-24] mm vs 19 [IQR: 17-22] mm; P < 0.001), greater maximum instantaneous left ventricular outflow tract (LVOT) gradient at rest (median: 67 [IQR: 36-96] mm Hg vs 47 [IQR: 19-79] mm Hg), and increased likelihood of moderate or greater mitral valve regurgitation (54.3% vs 47.3%; P = 0.001). However, PWT was not related to the severity of limitations measured by New York Heart Association functional class (P = 0.674). After adjusting for baseline covariates, greater PWT was an independent risk factor for late mortality after septal myectomy (P = 0.003).

CONCLUSIONS

PWT is a newly identified predictor of reduced long-term survival after septal myectomy that is independent of septal thickness and severity of LVOT gradient. Future studies are warranted to investigate the mechanisms underlying the association and the potential usefulness of PWT in patient management.

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 strong negative inotropic drugs potentially useful for symptom management.

Sex-related differences in left ventricular remodeling and outcome after alcohol septal ablation in hypertrophic obstructive cardiomyopathy: insights from cardiovascular magnetic resonance imaging

Background

Alcohol septal ablation (ASA) has been proven to reverse left ventricular (LV) remodeling in hypertrophic cardiomyopathy (HCM). However, there are no studies on the effect of sex on LV remodeling after ASA. We aimed to investigate whether sex differences affect the process of LV remodeling and outcome after ASA.

Methods

A total of 107 patients with obstructive HCM (54 men and 53 women, mean age 51 ± 8 years) were recruited. Cardiovascular magnetic resonance (CMR) was performed at baseline and 16 months after ASA. The extent of late gadolinium enhancement (LGE) was measured.

Results

Women had a higher indexed LV mass and smaller indexed LV end-systolic volumes than men at the time of ASA. After ASA, both men and women exhibited a regression of LV mass, and the percentage of mass regression was greater in men than women (15.3% ± 4.3% vs. 10.7% ± 1.8%, p < 0.001). In multivariable analysis, male sex, higher reduction of LV outflow tract (LVOT) gradient and lower baseline LV mass index were independently associated with greater LV mass regression after ASA. Kaplan–Meier analysis showed significantly higher cardiovascular events in women than in men (p = 0.015). Female sex [hazard ratio (HR) 3.913, p = 0.038] and LV mass preablation (HR, 1.019, p = 0.010) were independent predictors of cardiovascular outcomes.

Conclusions

Males with HCM had favorable reverse remodeling with greater LV mass regression post-ASA than female patients. This favorable LV reverse remodeling might provide a mechanistic explanation for the survival advantage in men.

Female patients with HCM showed worse LV remodeling with a higher indexed LV mass and a smaller indexed LV end-diastolic volume (measured by CMR) at the time of ASA.

Both men and women exhibited the LV reverse remodeling, however, men experienced more favorable LV reverse remodeling than women after ASA. The overall percentage of the LVM index regression was greater among men than women.

Women with HCM had worse relative composite endpoint than men. Sex and LV mass preablation were independent predictors of cardiovascular outcomes.

Sex appears to be a significant modifier in HCM patients receiving ASA treatment and highlighted the need for a different approach to women with HCM, such as improving women’s awareness of diagnosis and follow-up management as well as earlier referral for advanced therapies (e.g., septal reduction therapy and ICD implantation).

Clinical Characteristics and Healthcare Resource Utilization among Patients with Obstructive Hypertrophic Cardiomyopathy Treated in a Range of Settings in the United States

Obstructive hypertrophic cardiomyopathy (oHCM) has been studied primarily in comprehensive centers of excellence. Broadening the understanding of patients with oHCM in the general population may improve identification and treatment in other settings. This retrospective cohort study identified adults with oHCM from a large electronic medical record database comprising data from 39 integrated delivery networks (IBM Explorys; observational period: January 2009–July 2019). Clinical characteristics, healthcare resource utilization (HCRU), and outcomes were reported. Of 8791 patients, 53.0% were female and the mean index age was 61.8 years. Cardiovascular drugs prescribed included beta-blockers (80.5%), calcium channel blockers (46.0%), and disopyramide (2.4%). Over time, heart failure, atrial fibrillation, and ventricular arrhythmias increased. Surgical procedures included septal myectomy (22.0%), alcohol septal ablation (0.6%), and heart transplantation (0.3%). Implantable cardioverter defibrillators were present in 11.2% of patients. After initial septal reduction therapy (SRT), HCRU increased and 550 patients (27.7%) required a reintervention. Of the overall group, 2.7% experienced sudden cardiac arrest by end of study. In conclusion, this cohort of patients with oHCM had guideline-recommended drug therapy and procedures. Despite this, heart failure, atrial fibrillation, and ventricular arrhythmias increased, and more than a quarter of patients undergoing SRT required reintervention. These unresolved issues emphasize the unmet need for new, effective therapies for patients with oHCM.

Gender disparities in alcohol septal ablation for hypertrophic obstructive cardiomyopathy

OBJECTIVE

Alcohol septal ablation (ASA) improves symptoms in hypertrophic obstructive cardiomyopathy (HOCM). We conducted a large retrospective analysis investigating gender effects on outcome after ASA.

METHODS AND RESULTS

1367 ASAs between 2002 and 2020 were analysed. Women (47.2%) were older (66.0 years (IQR 55.0-74.0) vs 54.0 years (IQR 45.0-62.0); p<0.0001) with more severe symptoms. The interventricular septal diameter (IVSD) was higher in men (21.0 mm (IQR 19.0-24.0) vs 20.0 mm (IQR 18.0-23.0); p<0.0001) but the IVSD indexed to body surface area was higher in women (10.9 mm/m² (IQR 9.7-12.7) vs 10.2 mm/m² (IQR 9.0-11.7); p<0.0001). Women had lower exercise-induced left ventricular outflow tract gradients (LVOTG) 1-4 days after ASA (55.0 mm Hg (IQR 30.0-109.0) vs 71.0 mm Hg (IQR 37.0-115.0); p=0.0006). There was a trend for lower resting LVOTG 1-4 days after ASA (20.0 mm Hg (IQR 12.0-37.5) vs 22.0 mm Hg (IQR 13.0-40.0); p=0.0062) and lower exercise-induced LVOTG after 6 months in women (34.0 mm Hg (IQR 21.0-70.0) vs 43.5 mm Hg (IQR 25.0-74.8); p=0.0072), but this was not statistically significant after Bonferroni correction. More women developed atrioventricular (AV) block (20.3% vs 13.3%; p=0.0005) and required a pacemaker (17.4% vs 10.4%; p=0.0002) but not a cardioverter defibrillator (9.0% vs 11.6% in men; p=n .s.). However, in multivariable regression models, there was no evidence that sex independently influenced LVOTG and the occurrence of AV block.

CONCLUSION

Female patients with HOCM were older and had more advanced disease at the time of ASA. Women had superior short-term haemodynamic response to ASA but more often developed AV block after ASA. These results are important to consider for sex-specific counselling before ASA.

Sex-Related Differences in Genetic Cardiomyopathies

Cardiomyopathies are a heterogeneous collection of diseases that have in common primary functional and structural abnormalities of the heart muscle, often genetically determined. The most effective categorization of cardiomyopathies is based on the presenting phenotype, with hypertrophic, dilated, arrhythmogenic, and restrictive cardiomyopathy as the prototypes. Sex modulates the prevalence, morpho-functional manifestations and clinical course of cardiomyopathies. Aspects as diverse as ion channel expression and left ventricular remodeling differ in male and female patients with myocardial disease, although the reasons for this are poorly understood. Moreover, clinical differences may also result from complex societal/environmental discrepancies between sexes that may disadvantage women. This review provides a state-of-the-art appraisal of the influence of sex on cardiomyopathies, highlighting the many gaps in knowledge and open research questions.

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.

Thoracoscopic Trans-mitral Septal Myectomy for Hypertrophic Obstructive Cardiomyopathy in the Elderly

Background

The thoracoscopic trans-mitral approach can not only facilitate exposure of the ventricular septum, mitral valve, and subvalvular apparatus, it also enables the surgeons to perform concomitant mitral valve intervention. This study aimed to determine the safety and efficacy of thoracoscopic trans-mitral septal myectomy in elderly patients with hypertrophic obstructive cardiomyopathy (HOCM).

Methods

We reviewed the demographic to clinical characteristics and outcomes of patients who underwent thoracoscopic trans-mitral septal myectomy in our center between April 2019 and April 2021. The population was divided into a younger group (<60 years) and an elderly group (≥60 years).

Results

There were 46 and 20 patients in the younger and elderly groups, respectively. The majority of patients in the elderly group were female (39.1 vs. 80.0%, P < 0.01). Patients in the elderly group were more likely to be in New York Heart Association Class IV (2.2 vs. 80.0%, P < 0.01). The European System for Cardiac Operation Risk Evaluation II predicted mortality rates were significantly higher (3.97 ± 1.81 vs. 1.62 ± 0.86%, P < 0.01) in the elderly group. In the elderly group, a patient converted to median sternotomy due to left ventricular posterior free wall rupture following septal myectomy and mitral bioprosthetic valve replacement. The patient then underwent double-patch sandwich repair for rupture and mitral mechanical valve replacement and was eventually discharged. All patients in the elderly group were discharged, while one in the younger group died. No patient in the elderly group required permanent pacemaker implantation vs. one in the younger group. Patients in the elderly group were more likely to spend more time in the intensive care unit than those in the younger group (5.44 ± 5.80 days vs. 3.07 ± 2.72, P < 0.05). However, there was no significant intergroup difference in in-hospital mortality or complications. Importantly, the left ventricular outflow tract pressure gradient was significantly decreased from 96.15 ± 32.89 mmHg to 8.2 ± 3.42 mmHg with no residual obstruction in the elderly group. The interventricular septal thickness was significantly decreased from 19.73 ± 3.14 mm to 11.30 ± 2.23 mm. Postoperative mitral regurgitation severity was significantly improved in the elderly group.

Conclusion

This study demonstrated that thoracoscopic trans-mitral septal myectomy is a feasible option for selected elderly patients with satisfactory outcomes similar to those of young patients.

Sex differences in clinical outcomes for obstructive hypertrophic cardiomyopathy in the USA: a retrospective observational study of administrative claims data

OBJECTIVES

To evaluate sex differences in demographic and clinical characteristics, treatments and outcomes for patients with diagnosed obstructive hypertrophic cardiomyopathy (oHCM) in the USA.

SETTING

Retrospective observational study of administrative claims data from MarketScan Commercial Claims and Encounters Database from IBM Watson Health.

PARTICIPANTS

Of the 28 million covered employees and family members in MarketScan, 9306 patients with oHCM were included in this analysis.

MAIN OUTCOME MEASURES

oHCM-related outcomes included heart failure, atrial fibrillation, ventricular tachycardia/ fibrillation, sudden cardiac death, septal myectomy, alcohol septal ablation (ASA) and heart transplant.

RESULTS

Among 9306 patients with oHCM, the majority were male (60.5%, p<0.001) and women were of comparable age to men (50±15 vs 49±15 years, p<0.001). Women were less likely to be prescribed beta blockers (42.7% vs 45.2%, p=0.017) and undergo an implantable cardioverter-defibrillator (1.7% vs 2.6%, p=0.005). Septal reduction therapy was performed slightly more frequently in women (ASA: 0.08% vs 0.05%, p=0.600; SM: 0.35% vs 0.18%, p=0.096), although not statistically significant. Women were less likely to have atrial fibrillation (6.7% vs 9.9%, p<0.001).

CONCLUSION

Women were less likely to be prescribed beta blockers, ACE inhibitors, anticoagulants, undergo implantable cardioverter-defibrillator and have ventricular tachycardia/fibrillation. Men were more likely to have atrial fibrillation. Future research using large, clinical real-world data are warranted to understand the root cause of these potential treatment disparities in women with oHCM.

Sex and Race Disparities in Hypertrophic Cardiomyopathy: Unequal Implantable Cardioverter-Defibrillator Use During Hospitalization

OBJECTIVE

To evaluate if there are sex and race disparities in use of implantable cardioverter-defibrillator (ICD) devices for prevention of sudden cardiac death in patients with hypertrophic cardiomyopathy (HCM).

PATIENTS AND METHODS

Using the National Inpatient Sample from January 2003 through December 2014, we identified all adult admissions with a diagnosis of HCM and an ICD implantation. Race was classified as White versus non-White. Trends in ICD use, predictors of ICD implantation, device-related complications, hospitalization costs, and lengths of stay were evaluated.

RESULTS

Among a total of 23,535 adult hospitalizations for HCM, ICD implantation was performed in 3954 (16.8%) admissions. Over the study period, there was an overall increasing trend in ICD use (11.6% in 2003 to 17.0% in 2014, P<.001). Compared with admissions not receiving an ICD, those receiving an ICD had shorter median lengths of in-hospital stay but higher hospitalization costs (P<.001). Compared with men and White race, female sex (odds ratio, 0.72; 95% CI, 0.66 to 0.78; P<.001) and non-White race (odds ratio, 0.87; 95% CI, 0.79 to 0.96; P<.001) were associated with lower adjusted odds of receiving an ICD. Women and non-White hospitalizations had higher rates of device related complications, longer lengths of in-hospital stay, and higher hospitalization costs compared with men and White race, respectively (all P<.01).

CONCLUSION

Among HCM hospitalizations, ICD devices are underused in women and racial minorities independent of demographics, hospital characteristics, and comorbidities. Women and racial minorities also had higher rates of complications and greater resource use compared with men and those belonging to the White race, respectively.

Outcomes Over Follow-up ≥10 Years After Surgical Myectomy for Symptomatic Obstructive Hypertrophic Cardiomyopathy

For over 50 years, surgical septal myectomy has been the preferred treatment for drug-refractory heart failure symptoms in obstructive hypertrophic cardiomyopathy (HCM). However, given the relatively youthful adult ages at which HCM surgery is usually performed, it is informative to evaluate longer-term results of myectomy after ≥10 years. We identified 139 consecutive obstructive HCM patients (50 ± 15 years of age; 55% men) who underwent surgical myectomy, 2003 to 2010 at Tufts HCM Center and followed 11.3 ± 2.7 years (range to 17). Operative mortality was low (0.6%) and left ventricular (LV) outflow gradients at rest were reduced from 56 ± 40 mm Hg preoperatively to 1 ± 7 mm Hg postoperatively, durable over the study period, with no patient requiring reoperation for the residual gradient. Over follow-up, 129 of 139 patients (93%) were alive ≥10 years after myectomy, including 17 patients ≥15 years. Of 118 patients with complete long-term clinical follow-up data, 109 (92%) experienced clinical improvement to New York Heart Association classes I or II. In 9 patients (8%) refractory class III/IV symptoms reoccurred 6.6 ± 3.9 years postoperatively, including 4 who ultimately underwent a heart transplant. After myectomy, there were 2 late HCM-related deaths, but none suddenly; notably 6 patients (12%) with prophylactic implantable cardioverter-defibrillators experienced appropriate therapy terminating ventricular tachycardia/ventricular fibrillation after myectomy. Survival following myectomy was 91% at 10 years (95% confidence interval: 85, 96%) not different from the age- and gender-matched general United States population (log-rank p = 0.64). In conclusion, myectomy provides permanent abolition of outflow gradients with reversal of heart failure and highly favorable long-term survival, representing a low-risk:high-benefit option when performed in experienced HCM centers. Myectomy did not protect absolutely against arrhythmic sudden death events, underscoring the importance of risk stratification in operative patients.

Gender-Related Differences in Hypertrophic Cardiomyopathy: A Systematic Review and Meta-Analysis

Background

Gender-related differences in phenotypic expression and outcomes have been established in many cardiac conditions; however, the impact of gender in hypertrophic cardiomyopathy (HCM) remains unclear. We conducted a systematic review and meta-analysis to assess the differences in clinical outcomes between female and male HCM patients.

Methods

We searched MEDLINE and EMBASE from inception to October 2020. Included were cohort studies that compared outcomes of interest including all-cause mortality, HCM-related mortality, and worsening heart failure (HF) or HF hospitalization between male and female. Data from each study were combined using the random effects model to calculate pooled odds ratio (OR) with 95% confidence interval (CI).

Results

Eleven retrospective cohort studies with a total of 9,427 patients (3,719 females) were included. Female gender was significantly associated with an increased risk of all-cause mortality (pooled OR = 1.63, 95% CI: 1.26-2.10, p ≤ 0.001), HCM-related mortality (pooled OR = 1.47, 95% CI: 1.08-2.01, p = 0.015), and worsening HF or HF hospitalization (pooled OR = 2.05, 95% CI: 1.76-2.39, p ≤ 0.001).

Conclusions

Female gender was associated with a worse prognosis in HCM. These findings suggest the need for improved care in women including early identification of disease and more possible aggressive management. Moreover, gender-based strategy may benefit in HCM patients.

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.

Sex Differences in Time-Dependent Changes in B-Type Natriuretic Peptide in Hypertrophic Cardiomyopathy

Background: Female sex is reported to be associated with poor prognosis in hypertrophic cardiomyopathy (HCM). The plasma B-type natriuretic peptide (BNP) concentration is a prognostic predictor in HCM. However, the effect of sex on BNP concentrations remains unclear among HCM patients.

Methods and Results: Patient records in the Clinical Personal Records of HCM national database of the Japanese Ministry of Health, Labour and Welfare from 2009 to 2014 were analyzed. Of 3,570 HCM patients, 611 in whom BNP concentrations were assessed at both baseline and the 2-year follow-up were included in this analysis. The mean age was 60.4 years and 254 (41.6%) patients were female. Median (interquartile range) BNP concentrations were higher in females than males at both baseline (320.3 [159.0–583.1] vs. 182.8 [86.1–363.9] pg/mL; P<0.001) and the 2-year follow-up (299.2 [147.0–535.3] vs. 161.0 [76.2–310.0] pg/mL; P<0.001). Female sex was associated with higher natural log-transformed BNP at the 2-year follow-up regardless of clinical characteristics, including echocardiographic findings and BNP concentrations at baseline (coefficient 0.31; 95% confidence interval 0.13–0.48; P<0.001). Cubic spline analysis showed that, among patients with high BNP concentrations at baseline, females had higher BNP concentrations at the 2-year follow-up than males.

Conclusions: In HCM, female sex was associated with higher BNP concentrations than male sex, independent of clinical characteristics, including BNP concentrations at baseline.

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.

Genetic Testing in Patients with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a common inherited heart disease with an estimated prevalence of up to 1 in 200 individuals. In the majority of cases, HCM is considered a Mendelian disease, with mainly autosomal dominant inheritance. Most pathogenic variants are usually detected in genes for sarcomeric proteins. Nowadays, the genetic basis of HCM is believed to be rather complex. Thousands of mutations in more than 60 genes have been described in association with HCM. Nevertheless, screening large numbers of genes results in the identification of many genetic variants of uncertain significance and makes the interpretation of the results difficult. Patients lacking a pathogenic variant are now believed to have non-Mendelian HCM and probably have a better prognosis than patients with sarcomeric pathogenic mutations. Identifying the genetic basis of HCM creates remarkable opportunities to understand how the disease develops, and by extension, how to disrupt the disease progression in the future. The aim of this review is to discuss the brief history and recent advances in the genetics of HCM and the application of molecular genetic testing into common clinical practice.

Sex Differences in Hypertrophic Cardiomyopathy: Interaction With Genetics and Environment

Purpose of Review

We explore the sex-specific interaction of genetics and the environment on the clinical course and outcomes of hypertrophic cardiomyopathy (HCM).

Recent Findings

Women account for approximately one-third of patients in specialist HCM centres and reported in observational studies. As a result, evidence informing clinical guideline recommendations is based predominantly on risk factors and outcomes seen in men. However, disease progression appears to be different between the sexes. Women present at a more advanced stage of disease, are older at diagnosis, have higher symptom burden, carry greater risk for heart failure and are at greater risk of mortality compared to men. Women are more likely to be gene-positive, while men are more likely to be gene-negative. The risk of sudden cardiac death and access to specialised care do not differ between the sexes.

Summary

Reporting sex-disaggregated results is essential to identify the mechanisms leading to sex differences in HCM.

Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy in the Elderly

BACKGROUND

Hypertrophic obstructive cardiomyopathy (HOCM) is a genetic disorder treated with septal reduction therapy-either alcohol septal ablation or septal myectomy (SM). Historically, older patients have been presumed to be poor candidates for SM and thus referred directly for alcohol septal ablation in some centers. We reviewed our experience with SM in older patients.

METHODS

We identified 100 patients at our institution who underwent SM for HOCM from 2015-2020. Demographic and clinical characteristics and outcomes of patients 65 years or older were compared to patients less than 65.

RESULTS

There were 65 patients in the <65 group and 35 patients who were 65 or older. Both groups had similar preoperative peak stress left ventricular outflow tract gradients (129mmHg vs 110 mmHg, p<0.001). The majority of patients in both groups had moderate to severe mitral regurgitation (MR) on preoperative stress echocardiography. The elderly group was more likely to have coronary artery bypass graft as a concomitant procedure (37% vs 8%, p<0.001). There was only one death in the series secondary to a pulmonary embolism. At 30-day follow up on stress echo, peak stress gradients were normal in both groups (21 and 20mmHg, p=0<0.001) and 88% of all patients had trace to mild MR.

CONCLUSIONS

Properly selected older patients can safely undergo SM with excellent outcomes similar to younger patients. Relief of left ventricular outflow tract obstruction and correction of MR are reliably achieved in both groups. Advanced age should not be a strict criteria for selecting septal reduction therapy approach.

Impact of Body Mass Index on Outcome of Septal Myectomy for Obstructive Hypertrophic Cardiomyopathy

BACKGROUND

Obesity is highly prevalent in patients with obstructive hypertrophic cardiomyopathy (HCM). In this study, we investigated the impact of body mass index (BMI) in patients undergoing septal myectomy (SM) for obstructive HCM.

METHODS

We reviewed 2,746 patients who underwent transaortic SM for obstructive HCM from February 1993 through September 2018. Patients were stratified into 3 groups based on BMI (normal weight < 25 kg/m², overweight 25 to < 30 kg/m², and obese ≥ 30 kg/m²).

RESULTS

Preoperatively, median left ventricular outflow tract (LVOT) gradient was 58 mmHg, and there was no difference in gradients across BMI strata (P=0.35). Obese patients had lower percentage with moderate or greater mitral valve regurgitation (45.8%) compared to normal (52.9%) and overweight (55.4%) patients (P<0.001). However, patients with higher BMI were more likely to have New York Heart Association class III/IV limitation at presentation (P<0.001). After myectomy, both anteroseptal thickness (P=0.115) and LVOT gradient (P=0.210) did not differ between groups. There were 14 (0.5%) deaths < 30 days postoperatively and the risk was similar across BMI strata (P=0.448). Model-estimated changes in average BMI at 10 years post procedure showed stratum-specific increases ranging from 0.60 to 1.56 kg/m². During a median (IQR) follow-up of 7.2 (3.2-13.3) years, higher BMI was associated with reduced survival after adjusting for baseline covariates (P=0.001).

CONCLUSIONS

Septal myectomy is safe and effective in HCM patients with obesity, but risk of late mortality increased with increasing BMI. Attention to risk factor management through weight loss may improve late results after SM.

Sex differences in the prognosis of patients with hypertrophic cardiomyopathy

We investigated sex-related differences in the prognosis of patients with hypertrophic cardiomyopathy (HCM) using the Korea National Health Insurance Service database. From 2010 to 2016, 9524 patients diagnosed with HCM and had more than 1-year follow-up period were analyzed. The primary endpoint was the composite of cardiovascular death or new-onset heart failure (HF) admission. Propensity score-matching analysis was performed to adjust for different baseline characteristics. With a 4.4-years’ median follow-up interval (range 2.0–6.6 years) and male predominance (77.6%), women with HCM were older (52.6 ± 9.7 vs. 51.4 ± 9.1, p < 0.001), had lower incomes, more comorbidities based on Charlson comorbidity index. Women with HCM had a higher incidence of the primary endpoint than men (incidence rate: 34.15 vs. 22.83 per 1000 person-years, log-rank p < 0.001). Multivariable Cox analysis showed that female sex was a poor prognostic factor for the primary endpoint (HR 1.43, 95% CI 1.24–1.64, p < 0.001). This was mainly driven by a higher incidence of new-onset HF admission (HR 1.55, 95% CI 1.34–1.80). However, there was no difference in the incidence of cardiovascular death between the sexes. This result was concordant in the propensity score-matched cohort. In conclusion, women with HCM have worse prognosis, which was mainly driven by a higher new-onset HF admission.

Sex-related differences in symptomatic patients with hypertrophic obstructive cardiomyopathy - Time for a new definition?

INTRODUCTION

Sex-related differences in diagnosis and treatment of hypertrophic obstructive cardiomyopathy (HOCM) are still unclear. Therefore, we analyzed baseline characteristics of symptomatic patients with indication for alcohol septal ablation (PTSMA) with respect to gender.

METHODS AND RESULTS

Between 05/2000 and 06/2017 indication for PTSMA was seen in 1014 patients (420 (41.4%) women and 594 (58.6%) men). Women were older (61.4 ± 15.0 vs. 51.8 ± 13.6 years; p < 0.00001) and suffered more often from dyspnea NYHA III/IV (81.4% vs. 67.7%; p < 0.001), whereas angina pectoris and syncopes were comparable. Echocardiographic gradients were comparable in women (66.4 ± 39.1 mmHg at rest and 106.5 ± 46.6 mmHg at Valsalva) and men (62.7 ± 38.8 mmHg at rest and 103.7 ± 42.7 mmHg at Valsalva). Women had smaller absolute diameter of the left atrium (LA) (44.4 ± 6.9 vs. 47.2 ± 6.5 mm; p < 0.0001), septal thickness (IVS) (20.5 ± 4.1 vs. 21.4 ± 4.5 mm; p < 0.01), and left ventricular posterior wall thickness (LVPW) (12.7 ± 2.8 vs. 13.6 ± 2.9 mm; p < 0.0001). But, indexed for BSA the relationship reversed in LA (25.2 ± 4.3 mm/m² in women vs. 23.1 ± 3.4 mm/m²), IVS (11.7 ± 2.7 mm/m² in women vs. 10.6 ± 2.5 mm/m²) and LVPW (7.3 ± 1.7 mm/m² in women vs. 6.7 ± 1.6 mm/m²), p < 0.00001 each.

CONCLUSION

Women with HOCM and indication for PTSMA are older and more symptomatic with advanced disease progression. Reconsideration of disease definition and awareness maybe necessary in order to avoid delayed diagnosis and treatment of HOCM in women.