Nishimura, Rick A.

Once considered rare and essentially untreatable with a grim prognosis and reduced life expectancy, hypertrophic cardiomyopathy (HCM) has evolved substantially over 6 decades. Ultimately, HCM has become a contemporary global disease with pharmacologic and interventional options offering effective personalized treatment for all adverse disease pathways. Striking reduction in HCM‐related mortality to ≤0.5%/year in optimally treated cohorts is now comparable to that expected in the US general population, lower than most other disease risks to living, and 10‐fold less than the earliest estimates. The few deaths directly related to HCM are now largely attributable to advanced (end‐stage) heart failure in patients with nonobstructive HCM. Determinants of this transformation to a lower risk disease are evident in hallmark clinical inflection points and breakthroughs, including dedicated HCM programs assembling large clinical databases in which focused (and unfunded) physician‐investigators have derived data directly from patients in clinical practice. Evidence‐based observational studies report emergence of contemporary treatment strategies enhancing survival: implantable defibrillators prevent arrhythmic sudden death globally with 95% sensitive patient selection using an American Heart Association/American College Cardiology risk stratification algorithm; low‐risk, high‐benefit surgical myectomy reverses outflow obstruction and heart failure in >90% with a long‐term survival benefit; and aggressive anticoagulation has reduced embolic strokes. Recent novel pharmacologic alternatives (cardiac myosin inhibitors) are proving effective in relieving obstruction/symptom burden and changing disease management. These principles and time‐tested patient‐centered research strategies uniquely tailored to the heterogeneous HCM clinical spectrum are pivotal in providing practice insights, offering a vulnerable population more optimistic prognosis including opportunity to achieve normal longevity not available to prior generations of patients.

Importance Primary mitral regurgitation (MR) is a prevalent valvular lesion. Current American College of Cardiology/American Heart Association guidelines include class I recommendations for intervention for severe primary MR at the onset of symptoms, significant left ventricular (LV) enlargement (end-systolic dimension ≥40 mm), or dysfunction (ejection fraction ≤60%), with a class IIA recommendation for mitral valve repair when performed at an experienced surgical center. Recent data suggest a survival penalty when waiting for class I surgical guideline indications, and novel markers of decompensation are under investigation. Observations Comprehensive assessment of MR severity using echocardiography is critical, and when warranted, cardiac magnetic resonance (CMR) is complementary. Assessment of LV size and function, as well as serial changes in both, is crucial for determining timing of surgery. New-onset atrial fibrillation, left atrial enlargement, pulmonary hypertension, and exercise-induced changes in LV function should also be considered in borderline scenarios. The roles of LV volumes, global longitudinal strain, CMR-derived measures of myocardial dysfunction, and cardiac biomarkers are worthy of further investigation regarding consideration for early surgical intervention. Conclusions and Relevance A more refined approach incorporating assessment of extravalvular cardiac injury, novel imaging markers, and biomarkers is needed to optimize surgical timing in primary MR. Further research is warranted to validate these emerging parameters and refine guidelines to improve patient outcomes.

Introduction: Obesity is an independent risk factor for heart failure in patients with hypertrophic cardiomyopathy (HCM). Bariatric surgery is associated with improved cardiac function in obese patients with heart failure, but the safety of this procedure has not been evaluated in HCM patients. In this study, we examined national trends and early outcomes in bariatric surgery for patients with HCM. Methods: Using the weighted discharge data from the National Inpatient Sample, we identified adult patients with HCM who underwent elective bariatric surgery for obesity between 2011 and 2017. Patients with a history of bariatric surgery or having malignant neoplasms in the esophagus, stomach, small intestine, or pancreas were excluded. Results: A total of 443 obese patients with HCM were identified, and 41.8% (n=185) had obstructive HCM. The annual number of patients increased from 18 in 2011 to 130 in 2017, and nearly half of the patients (48%) had bariatric surgery in 2016 and 2017. Overall, the median (IQR) age was 50 (43-57) years, and 85 (19%) patients 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 (19%) patients, and 22% (n=95) of the cohort had a pacemaker or automatic cardiac defibrillator implanted prior to 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 hospital for a median (IQR) of 2 (1-2) days. During the hospital stay, 1% (n=5) of the patients had acute worsening of chronic heart failure, but there were no deaths, cardiac arrests, or cerebrovascular accidents post procedure. Conclusions: Bariatric surgery in patients with HCM is performed more frequently in recent years and is safe and associated with few perioperative complications. Given the impact of obesity on long-term survival, clinicians should strongly consider bariatric surgery for HCM patients who do not respond to conservative weight loss measures.

Background: Treatment of progressive heart failure, due to left ventricular (LV) outflow tract obstruction has been a major component of hypertrophic cardiomyopathy (HCM) disease management for 50 years. Septal myectomy has been the primary treatment option to abolish gradients and relieve heart failure symptoms. The role of myectomy in HCM management has depended on effectiveness in relieving heart failure symptoms, but also an acceptable operative risk. Methods: Over the most recent 15-year period, we reviewed 3,700 consecutive isolated myectomy operations performed at major North American HCM institutions. Composite operative mortality (first 30 days) was only 0.4%. Seventeen operative deaths were at ages 24 to 82 (≥70 years), and only 6 occurred after 2010. Notably, 2 of the 4 Mayo Clinic deaths were in patients with prior alcohol septal ablation. Septal myectomy, when performed in experienced HCM centers, was much safer when compared to operative mortality with coronary artery bypass grafting (2.3%); valve replacement (3.5%); mitral valve replacement specifically (5.7%) (STS Database), similar to atrial or ventricular septal defect closure and 15-fold less than myectomy in community hospital or low volume surgical settings. Conclusions: Surgical myectomy performed in dedicated HCM centers with experienced surgeons and staff is one of the safest open-heart procedures currently practiced, with a mortality rate as low as 0.4%. The large mortality discrepancy for myectomy between community hospitals and dedicated HCM centers underscores that this operation should be considered a specialized procedure best performed in high volume HCM institutions.

Background Aortic valve calcium score is associated with hemodynamic severity of aortic stenosis. Whether this association is present in calcific mitral stenosis remains unknown. Methods and Results This study was a retrospective analysis of consecutive patients with mitral stenosis secondary to mitral annular calcification (MAC) undergoing transseptal catheterization. All patients underwent invasive mitral valve assessment via direct left atrial and left ventricular pressure measurement. Computed tomography within 1 year of cardiac catheterization and with adequate visualization of the mitral annulus was included. MAC calcium score quantification by Agatston method was obtained offline using dedicated software (Aquarius, TeraRecon, V.4). Median patient age was 66.9±11.2 years, 47% of patients were women, 50% had coronary artery disease, 40% had atrial fibrillation, 47% had prior cardiac surgery, and 33% had prior chest radiation. Median diastolic mitral valve gradient was 9.4±3.4 mm Hg on echocardiography and 8.5±4 mm Hg invasively. Invasive median mitral valve area using the Gorlin formula was 1.87±0.9 cm 2 . Median MAC calcium score for the cohort was 7280±7937 Hounsfield units. MAC calcium score correlated with the presence of atrial fibrillation ( P =0.02) but was not associated with other comorbidities. There was no correlation between MAC calcium score and mitral valve area ( r =0.07; P =0.6) or mitral valve gradient ( r =−0.03; P =0.8). Conclusions MAC calcium score did not correlate with invasively measured mitral valve gradient and mitral valve area in patients with MAC‐related mitral stenosis, suggesting that calcium score should not be used as a surrogate for invasive hemodynamic parameters.

BACKGROUND: Alcohol septal ablation (ASA) is a minimally invasive treatment for drug-refractory obstructive hypertrophic cardiomyopathy. Detailed assessment of pressure changes and predictors of mortality and procedure success are not well defined. METHODS: This is a single-center study evaluating pressure changes and predictors of mortality and procedure success in transseptal ASA. Survival analysis and predictors of mortality were assessed using the Kaplan-Meier analysis and Cox regression, respectively. RESULTS: A total of 156 patients were included (mean age, 67.3 years; 46.8% women). Left atrial (LA) pressure and left ventricular outflow tract (LVOT) gradient decreased, whereas aortic pulse pressure (PP) increased post-ASA. Patients with lower baseline mean LA pressure (<median, 19 mm Hg), LVOT gradient reduction >82% (gradient change median), and PP increase >19% (PP change median) had superior survival. On Cox univariable regression, baseline mean LA pressure >median (19 mm Hg; hazard ratio [HR], 2.09 [95% CI, 1.05–4.18]; P =0.036), residual LVOT gradient (HR, 1.02 [95% CI, 1.01–1.03]; P =0.003), and LVOT gradient percent reduction <median (82%; HR, 2.92 [95% CI, 1.46–5.83]; P =0.002) were predictors of mortality. When adjusting for age and sex, baseline LA v wave >median (28 mm Hg; HR, 2.36 [95% CI, 1.17–4.76]; P =0.016), baseline mean LA pressure >median (19 mm Hg; HR, 2.70 [95% CI, 1.33–5.50]; P =0.006), percentage reduction in gradient <median (82%; HR, 2.74 [CI, 1.37–5.50]; P =0.005), and percentage increase in PP <median (19.3%; HR, 2.09 [CI, 1.05–4.16]; P =0.035) predicted survival free of all-cause mortality. CONCLUSIONS: ASA is associated with an acute decrease in the LVOT gradient and LA pressures and increase in aortic PP. Mean LA pressure, percentage decrease in LVOT gradient, and increase in PP are strong predictors of survival free of all-cause mortality following ASA and are important variables for procedural guidance.

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.

Background The aim of this study was to establish prognostic hemodynamic parameters in patients with mitral stenosis secondary to mitral annular calcification. Methods and Results A retrospective cohort of 105 patients undergoing transseptal catheterization for hemodynamic evaluation of mitral annular calcification–related mitral stenosis between 2004 and 2020 was studied. Mitral valve gradient (MVG) and mitral valve area (MVA; calculated by the Gorlin formula) were measured using direct left atrial and left ventricular pressures. The median age of the patients was 70.3 years (58.4–76.7 years), and 53.3% were women. The median MVA was 1.7 cm 2 (1.3–2.3 cm 2 ) and MVG was 7.3 mm Hg (5.3–10.3 mm Hg); left ventricular end‐diastolic pressure was 17.6±28.3 mm Hg. During a median of 2.1 years (0.7–4.5 years), there were 63 deaths; 1‐ and 5‐year survival were 76% and 40%, respectively. There was no association between left ventricular end‐diastolic pressure and survival. After adjusting for age and comorbidities, both MVA (hazard ratio [HR], 0.50 per cm 2 ; 95% CI, 0.34–0.73) and MVG (HR, 1.1 per mm Hg; 95% CI, 1.05–1.20) were independent predictors of death. Atrial fibrillation was also independently associated with mortality. When added to a combined model, MVA remained associated with death (HR, 0.51 per cm 2 ; 95% CI, 0.33–0.79) while MVG was not. Conclusions In patients with mitral annular calcification–related mitral stenosis, survival was poor. MVA and MVG were independently associated with death, but MVA was a better predictor of outcomes.

AbstractBackgroundMitral transcatheter edge‐to‐edge repair (MTEER) is an established therapeutic approach for mitral regurgitation (MR). Functional mitral regurgitation originating from atrial myopathy (A‐FMR) has been described.ObjectivesWe sought to assess the clinical, echocardiographic and hemodynamic considerations in A‐FMR patients undergoing MTEER.MethodsFrom 2014 to 2020, patients undergoing MTEER for degenerative MR (DMR), functional MR (FMR), and mixed MR were assessed. A‐FMR was defined by the presence of MR > moderate in severity; left ventricular (LV) ejection fraction (LVEF) ≥ 50%; and severe left atrial (LA) enlargement in the absence of LV dysfunction, leaflet pathology, or LV tethering. The diagnosis of A‐FMR (vs. ventricular‐FMR [V‐FMR]) was confirmed by three independent echocardiographers. Baseline characteristics, procedural outcomes as well as clinical and echocardiographic follow‐up are reported. Device success was defined as final MR grade ≤ moderate; MR reduction ≥1 grade; and final transmitral gradient <5 mmHg.Results306 patients underwent MTEER, including DMR (62%), FMR (19%), and mixed MR (19%). FMR cases included 37 (63.8%) V‐FMR and 21 (36.2%) A‐FMR. Tricuspid regurgitation (≥ moderate) was higher in A‐FMR (80.1%) compared to V‐FMR (54%) and DMR (42%). Device success did not significantly differ between A‐FMR and V‐FMR (57% vs. 73%, p = 0.34) or DMR (57% vs. 64%, p = 1.0). The A‐FMR cohort was less likely to achieve ≥3 grades of MR reduction compared to V‐FMR (19% vs. 54%, p = 0.01) and DMR (19% vs. 49.7%, p = 0.01). Patients with V‐FMR and DMR demonstrated significant reductions in mean left atrial pressure (LAP) and peak LA V‐wave, though A‐FMR did not (LAP −0.24 ± 4.9, p = 0.83; peak V‐wave −1.76 ± 9.1, p = 0.39). In follow‐up, echocardiographic and clinical outcomes were similar.ConclusionsIn patients undergoing MTEER, A‐FMR represents one‐third of FMR cases. A‐FMR demonstrates similar procedural success but blunted acute hemodynamic responses compared with DMR and V‐FMR following MTEER. Dedicated studies specifically considering A‐FMR are needed to discern the optimal therapeutic approaches.