Iron deficiency in pulmonary vascular disease: pathophysiological and clinical implications.

AIMS: Iron deficiency is common in pulmonary hypertension, but its clinical significance and optimal definition remain unclear. METHODS AND RESULTS: Phenotypic data for 1028 patients enrolled in the Redefining Pulmonary Hypertension through Pulmonary Vascular Disease Phenomics study were analyzed. Iron deficiency was defined using the conventional heart failure definition and also based upon optimal cut-points associated with impaired peak oxygen consumption (peakVO2), 6-min walk test distance, and 36-Item Short Form Survey (SF-36) scores. The relationships between iron deficiency and cardiac and pulmonary vascular function and structure and outcomes were assessed. The heart failure definition of iron deficiency endorsed by pulmonary hypertension guidelines did not identify patients with reduced peakVO2, 6-min walk test, and SF-36 (P > 0.208 for all), but defining iron deficiency as transferrin saturation (TSAT) <21% did. Compared to those with TSAT ≥21%, patients with TSAT <21% demonstrated lower peakVO2 [absolute difference: -1.89 (-2.73 to -1.04) mL/kg/min], 6-min walk test distance [absolute difference: -34 (-51 to -17) m], and SF-36 physical component score [absolute difference: -2.5 (-1.3 to -3.8)] after adjusting for age, sex, and hemoglobin (all P < 0.001). Patients with a TSAT <21% had more right ventricular remodeling on cardiac magnetic resonance but similar pulmonary vascular resistance on catheterization. Transferrin saturation <21% was also associated with increased mortality risk (hazard ratio 1.63, 95% confidence interval 1.13-2.34; P = 0.009) after adjusting for sex, age, hemoglobin, and N-terminal pro-B-type natriuretic peptide. CONCLUSION: The definition of iron deficiency in the 2022 European Society of Cardiology (ESC)/European Respiratory Society (ERS) pulmonary hypertension guidelines does not identify patients with lower exercise capacity or functional status, while a definition of TSAT <21% identifies patients with lower exercise capacity, worse functional status, right heart remodeling, and adverse clinical outcomes.

Magnetic resonance imaging of cardiac metabolism in heart failure: how far have we come?

As one of the highest energy consumer organs in the body, the heart requires tremendous amount of adenosine triphosphate (ATP) to maintain its continuous mechanical work. Fatty acids, glucose, and ketone bodies are the primary fuel source of the heart to generate ATP with perturbations in ATP generation possibly leading to contractile dysfunction. Cardiac metabolic imaging with magnetic resonance imaging (MRI) plays a crucial role in understanding the dynamic metabolic changes occurring in the failing heart, where the cardiac metabolism is deranged. Also, targeting and quantifying metabolic changes in vivo noninvasively is a promising approach to facilitate diagnosis, determine prognosis, and evaluate therapeutic response. Here, we summarize novel MRI techniques used for detailed investigation of cardiac metabolism in heart failure including magnetic resonance spectroscopy (MRS), hyperpolarized MRS, and chemical exchange saturation transfer based on evidence from preclinical and clinical studies and to discuss the potential clinical application in heart failure.

Characterization of cardiac amyloidosis using cardiac magnetic resonance fingerprinting.

BACKGROUND: Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy with poor prognosis absent appropriate treatment. Elevated native myocardial T1 and T2 have been reported for CA, and tissue characterization by cardiac MRI may expedite diagnosis and treatment. Cardiac Magnetic Resonance Fingerprinting (cMRF) has the potential to enable tissue characterization for CA through rapid, simultaneous T1 and T2 mapping. Furthermore, cMRF signal timecourses may provide additional information beyond myocardial T1 and T2. METHODS: Nine CA patients and five controls were scanned at 3 T using a prospectively gated cMRF acquisition. Two cMRF-based analysis approaches were examined: (1) relaxometric-based linear discriminant analysis (LDA) using native T1 and T2, and (2) signal timecourse-based LDA. The Fisher coefficient was used to compare the separability of patient and control groups from both approaches. Leave-two-out cross-validation was employed to evaluate the classification error rates of both approaches. RESULTS: Elevated myocardial T1 and T2 was observed in patients vs controls (T1: 1395 ± 121 vs 1240 ± 36.4 ms, p < 0.05; T2: 36.8 ± 3.3 vs 31.8 ± 2.6 ms, p < 0.05). LDA scores were elevated in patients for relaxometric-based LDA (0.56 ± 0.28 vs 0.18 ± 0.13, p < 0.05) and timecourse-based LDA (0.97 ± 0.02 vs 0.02 ± 0.02, p < 0.05). The Fisher coefficient was greater for timecourse-based LDA (60.8) vs relaxometric-based LDA (1.6). Classification error rates were lower for timecourse-based LDA vs relaxometric-based LDA (12.6 ± 24.3 vs 22.5 ± 30.1%, p < 0.05). CONCLUSIONS: These findings suggest that cMRF may be a valuable technique for the detection and characterization of CA. Analysis of cMRF signal timecourse data may improve tissue characterization as compared to analysis of native T1 and T2 alone.

Worsened Tricuspid Regurgitation Following Pericardiectomy for Constrictive Pericarditis.

BACKGROUND: Worsening tricuspid regurgitation (TR) severity may occur after pericardiectomy surgery for constrictive pericarditis patients; however, its mechanisms and predictors are not well established. We evaluated the clinical characteristics, associated factors, and outcomes of worsening TR after pericardiectomy. METHODS: Consecutive patients undergoing pericardiectomy for constrictive pericarditis without tricuspid valve surgery and with pre- and postoperative echocardiography available during 2000 to 2017 were retrospectively studied. Clinical, imaging, hemodynamic, and mortality characteristics were analyzed by those with and without worsening TR by at least one grade. RESULTS: Among 381 patients (age 61 [17] years, 318 [83.5%] male), 193 (50.7%) had worsening TR post-operatively, and 75 died during the 2.5 (5.4) years follow-up. In univariable analysis, worsening TR was associated with a history of congestive heart failure (47.2% versus 31.9%, P=0.003), increased left atrial volume indexed (23 versus 20 mL/m2, P=0.020), reduced right ventricular fractional area change (47% versus 54%, P<0.001), and worsening mitral regurgitation (39.7% versus 16.6%, P<0.001). Worsened TR had a trend toward reduced survival during follow-up (log-rank P=0.080), especially those with worsened TR but no recovery of TR grade on subsequent echocardiography within the first year compared with those without worsened TR (log-rank P=0.02). In multivariable analysis, right ventricular fractional area change, left atrial volume indexed, left ventricular mass indexed, pulmonary artery systolic pressure, and right atrial pressure/pulmonary capillary wedge pressure ratio were most associated with worsened TR, while blood urea nitrogen, hematocrit, lateral and medial e' tissue Doppler and heart rate were most associated with mortality during follow-up. CONCLUSIONS: Worsening TR severity was prevalent after pericardiectomy and had a trend toward reduced survival, especially if TR severity did not recover on subsequent echocardiography. Presence of parameters associated with worsened TR and reduced survival should alert clinicians to carefully manage these patients during follow-up.

Arrhythmias in Cardiac Sarcoidosis Bench to Bedside: A Case-Based Review.

Cardiac sarcoidosis is a component of an often multiorgan granulomatous disease of still uncertain cause. It is being recognized with increasing frequency, mainly as the result of heightened awareness and new diagnostic tests, specifically cardiac magnetic resonance imaging and 18F-fluorodeoxyglucose positron emission tomography scans. The purpose of this case-based review is to highlight the potentially life-saving importance of making the early diagnosis of cardiac sarcoidosis using these new tools and to provide a framework for the optimal care of patients with this disease. We will review disease mechanisms as currently understood, associated arrhythmias including conduction abnormalities, and atrial and ventricular tachyarrhythmias, guideline-directed diagnostic criteria, screening of patients with extracardiac sarcoidosis, and the use of pacemakers and defibrillators in this setting. Treatment options, including those related to heart failure, and those which may help clarify disease mechanisms are included.

Reference Ranges, Diagnostic and Prognostic Utility of Native T1 Mapping and Extracellular Volume for Cardiac Amyloidosis: A Meta-Analysis.

BACKGROUND: Cardiac MRI is central to the evaluation of cardiac amyloidosis (CA). Native T1 mapping and extracellular volume (ECV) are novel MR techniques with evolving utility in cardiovascular diseases, including CA. PURPOSE: To perform a meta-analysis of the diagnostic and prognostic data of native T1 mapping and ECV techniques for assessing CA. STUDY TYPE: Systematic review and meta-analysis. POPULATION: In all, 3520 patients including 1539 with CA from 22 studies retrieved following systematic search of Pubmed, Cochrane, and Embase. FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T/modified Look-Locker inversion recovery (MOLLI) or shortened MOLLI (shMOLLI) sequences. ASSESSMENT: Meta-analysis was performed for all CA and for light-chain (AL) and transthyretin (ATTR) subtypes. Thresholds were calculated to classify native T1 and ECV values as not suggestive, indeterminate, or suggestive of CA. STATISTICAL ANALYSIS: Area under the receiver-operating characteristic curves (AUCs) and hazards ratios (HRs) with 95% confidence intervals (95% CI) were pooled using random-effects models and Open-Meta(Analyst) software. RESULTS: Six studies were diagnostic, 16 studies reported T1 and ECV values to determine reference range, and six were prognostic. Pooled AUCs (95% CI) for diagnosing CA were 0.92 (0.89-0.96) for native T1 mapping and 0.96 (0.93-1.00) for ECV, with similarly high detection rates for AL- and ATTR-CA. Based on the pooled values of native T1 and ECV in CA and control subjects, the thresholds that suggested the absence, indeterminate, or presence of CA were identified as <994 msec, 994-1073 msec, and >1073 msec, respectively, for native T1 at 1.5T. Pooled HRs (95% CI) for predicting all-cause mortality were 1.15 (1.08-1.22) for native T1 mapping as a continuous parameter, 1.19 (1.01-1.40) for ECV as a continuous parameter, and 4.93 (2.64-9.20) for ECV as a binary threshold. DATA CONCLUSION: Native T1 mapping and ECV had high diagnostic performance and predicted all-cause mortality in CA. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY STAGE: 2.

Impact of timing of atrial fibrillation, CHA2DS2-VASc score and cancer therapeutics on mortality in oncology patients.

OBJECTIVES: To investigate timing and age distribution of atrial fibrillation (AF) in selected oncology patients, and the impact of AF timing, CHA2DS2-VASc score and cancer therapeutics on mortality. METHODS: This is a retrospective cohort study of oncology patients referred to the cardio-oncology service from 2011 to 2018 for echocardiographic cardiosurveillance and/or pre-existing cardiovascular risk factor/disease management. Rates of first AF diagnosis was assessed using a parametric multiphase hazard model (predictive modelling) and non-parametrically by Kaplan-Meier with transformations tested using a bootstrap methodology. RESULTS: Among 6754 patients identified, 174 patients had their first AF diagnosis before cancer while 609 patients had their first diagnosis of AF after cancer. Most first AF diagnosis occurred at/early after cancer diagnosis. Increasing AF prevalence at time of cancer diagnosis was seen across older age groups ranges. Diagnosis of cancer at an older age and exposure to cardiotoxic treatment (anthracyclines, HER2-neu inhibitors, tyrosine kinase inhibitors including ibrutinib and radiation) were associated with an increased risk of AF.Modelling of the hazard function of AF identified a high left-skewed peak within 3 years after cancer diagnosis ('early phase'), followed by a gradual late slight rise 3 years after cancer diagnosis ('late phase'). AF diagnosis was only associated with death in the early phase (p<0.001), while CHA2DS2-VASc score was only associated with death in the late phase (p<0.001). CONCLUSIONS: This study reports a nuanced/complex relationship between AF and cancer. First diagnosis of AF in patients with cancer was more common at/early after cancer diagnosis, especially in older patients and those exposed to cardiotoxic treatment. Pre-existing AF or a diagnosis of AF within 3 years after cancer diagnosis carried a negative prognosis. CHA2DS2-VASc score did not relate to mortality in those that developed AF within 3 years of cancer diagnosis.

Multimodality imaging in patients with post-cardiac injury syndrome.

This review article is focused on the role of echocardiography, cardiac CT and cardiac magnetic resonance (CMR) imaging in diagnosing and managing patients with post-cardiac injury syndrome (PCIS). Clinically, the spectrum of pericardial diseases under PCIS varies not only in form and severity of presentation but also in the timing varying from weeks to months, thus making it difficult to diagnose. Pericarditis developing after recent or remote myocardial infarction, cardiac surgery or ablation if left untreated or under-treated could worsen into complicated pericarditis which can lead to decreased quality of life and increased morbidity. Colchicine in combination with other anti-inflammatory agents (non-steroidal anti-inflammatory drugs) is proven to prevent and treat acute pericarditis as well as its relapses under various scenarios. Imaging modalities such as echocardiography, CT and CMR play a pivotal role in diagnosing PCIS especially in difficult cases or when clinical suspicion is low. Echocardiography is the tool of choice for emergent bedside evaluation for cardiac tamponade and to electively study the haemodynamics impact of constrictive pericarditis. CT can provide information on pericardial thickening, calcification, effusions and lead perforations. CMR can provide pericardial tissue characterisation, haemodynamics changes and guide long-term treatment course with anti-inflammatory agents. It is important to be familiar with the indications as well as findings from these multimodality imaging tools for clinical decision-making.

Emerging role of multimodality imaging in management of inflammatory pericardial diseases.

The non-specific and highly variable symptomatology of inflammatory pericardial diseases create clinical challenges in making accurate diagnosis, which often requires the integration of clinical findings, imaging and invasive hemodynamic assessment. Echocardiography is considered to be a first-line imaging test in pericardial diseases. Emerging imaging modalities, especially cardiac MRI allowed better understanding of pericardial anatomy, physiology and, for the first time, enable demonstration of the pericardial inflammation. On the other hand, cardiac computed tomography is excellent tool to define pericardial thickness, pericardial calcification and is useful for preoperative planning once pericardiectomy is indicated especially in the patients with prior cardiac surgery.

Survival in patients with severe ischemic cardiomyopathy undergoing revascularization versus medical therapy: association with end-systolic volume and viability.

BACKGROUND: The value of assessment of viability as a predictor of surgical revascularization benefit in ischemic cardiomyopathy has recently been questioned in a large trial. We sought to determine whether the contribution of viability as myocardial scar burden (SB) to predict revascularization outcomes could be modulated by end-systolic volume index (ESVi). METHODS AND RESULTS: Delayed hyperenhancement-MRI was obtained in 450 patients with ≥70% stenosis in ≥1 epicardial coronary artery (75% men; median age, 62.8 ± 10.7 years; mean left ventricular ejection fraction, 23 ± 9%; mean ESVi, 115 ± 50 mL) from 2002 to 2006. SB was quantified as scar percentage (infarcted mass/total left ventricular mass). Subsequent surgical revascularization was performed in 245 (54%) patients and subsequent percutaneous coronary interventions were performed in 28 (6%) patients. A propensity score was developed for revascularization. Cox proportional hazards models of all-cause mortality were used for risk adjustment. Over a mean follow-up of 5.8 ± 2.7 years, 186 (41%) deaths occurred. After adjusting for prior revascularization, sex, diabetes, age, use of cardiac resynchronization therapy, implantable cardioverter defibrillator, mitral regurgitation, and mitral valve procedures; an interaction between scar percentage and ESVi (P=0.016) and an interaction between post-MRI revascularization and ESVi (P=0.0017) were independently associated with mortality. ESVi demonstrated a significant interaction with revascularization and female sex, such that enhanced survival was associated with ESVi. ESVi also showed an interaction with SB; better survival was associated with lower volumes and less scar. CONCLUSIONS: ESVi and SB provide independent, incremental prognostic value in patients with severe ischemic cardiomyopathy. The risk associated with SB should not be assessed in isolation.

Pericardial delayed hyperenhancement with CMR imaging in patients with constrictive pericarditis undergoing surgical pericardiectomy: a case series with histopathological correlation.

OBJECTIVES: The purpose of this study was to examine the prevalence and histopathologic correlates of pericardial delayed hyperenhancement (DHE) seen with cardiac magnetic resonance imaging (CMR) among patients with constrictive pericarditis (CP) undergoing pericardiectomy. BACKGROUND: Constrictive pericarditis patients studied by CMR will occasionally demonstrate pericardial DHE following gadolinium contrast administration. METHODS: We identified 25 CP patients who underwent pericardiectomy following CMR-gadolinium study. We also assessed 10 control subjects with no evidence of pericardial disease referred for cardiac viability imaging. A novel 14-segment pericardial model was used to determine pericardial DHE score and thickness score. Histopathology of pericardial specimens was reviewed and evaluated semiquantitatively on a 4-point scale for the extent of calcification, fibrosis, inflammation, and neovascularization. RESULTS: DHE was present in 12 (48%) CP patients (DHE+ group), and absent in 13 CP patients (DHE- group) and all control patients. The DHE+ group had greater fibroblastic proliferation and neovascularization, as well as more prominent chronic inflammation and granulation tissue. Fibroblastic proliferation and chronic inflammation correlated with DHE presence quantitated by DHE score (Spearman r = 0.578, p < 0.002, and r = 0.590, p < 0.002, respectively), but not with pericardial thickness. Segmental analysis demonstrated no significant difference in the percentage of patients with different pericardial segmental thickness; however, overall, in each segment, the DHE+ group tended to have greater pericardial thickness. CONCLUSIONS: The presence of pericardial DHE on CMR is common in patients with CP, and its presence is associated with histological features of organizing pericarditis, which may be a target for future focused pharmacological interventions. Patients with CP without pericardial DHE had more pericardial fibrosis and calcification, as well as lesser degrees of pericardial thickening.

Lessons from regadenoson and low-level treadmill/regadenoson myocardial perfusion imaging: initial clinical experience in 1263 patients.

BACKGROUND: Regadenoson is a pharmacologic stress agent, which was recently approved for stress myocardial perfusion imaging (MPI). Aside from the initial protocol-driven studies, clinical experience with this stress agent is limited. Furthermore, low-level treadmill testing in a large population with regadenoson has not previously been evaluated. We describe our experience in the first 6 months of routine inpatient and outpatient clinical use. METHODS: Between 7/1/08 and 12/04/08, 1263 patients underwent regadenoson stress testing (596 with low-level treadmill, 667 supine). Past medical history, clinical symptoms during stress, and changes in systolic blood pressure were prospectively recorded. RESULTS: Low-level treadmill testing was well tolerated in our patient population. Shortness of breath, dizziness, palpitations, transient heart block, and nausea were less frequent when patients were able to exercise. In our population, 51% experienced a drop in systolic blood pressure greater than 10 mmHg, with 9% experiencing a decrease in more than 30 mmHg. This decrease in blood pressure was more common in patients who underwent low-level treadmill testing vs those that were supine (56% vs 47%, P-value < 0.001). The frequency of symptoms in our entire population was as follows: chest pain 35%, dizziness/lightheadedness 16%, shortness of breath 27%, headache 1.4%, nausea 2.3%, and palpitations 5%. There were no major hemodynamic or conduction abnormalities. In the 16% of patients, a history of COPD/Asthma Regadenoson MPI was well tolerated. There were no procedural deaths. CONCLUSION: Regadenoson and Regadenoson combined with low level exercise MPI appear to be safe and well tolerated. An asymptomatic fall in systolic blood pressure seems to be more common in patients who undergo low-level treadmill testing.

Characteristics and surgical outcomes of symptomatic patients with hypertrophic cardiomyopathy with abnormal papillary muscle morphology undergoing papillary muscle reorientation.

OBJECTIVE: In patients with hypertrophic cardiomyopathy with bifid hypermobile papillary muscles and a dynamic left ventricular outflow tract gradient, we performed surgical papillary muscle reorientation, fixing the mobile papillary muscle to the posterior left ventricle to reduce mobility. We report the outcomes of patients with hypertrophic cardiomyopathy undergoing surgical papillary muscle reorientation versus those of patients undergoing standard surgical procedures. METHODS: We studied 204 consecutive patients with hypertrophic cardiomyopathy undergoing surgical intervention (after consensus decision) for symptomatic left ventricular outflow tract gradient. Preoperative and postoperative maximal (resting/provocable) left ventricular outflow tract gradients were recorded by using echocardiographic analysis. RESULTS: The population was divided into 3 groups: (1) isolated myectomy (n = 143; age, 54 +/- 14 years; 48% men), (2) myectomy plus mitral valve repair/replacement (n = 39; age, 54 +/- 13 years; 54% men), and (3) papillary muscle reorientation with or without myectomy (n = 22; age, 50 +/- 14 years; 59% men). The mean preoperative (103 +/- 32, 103 +/- 32, and 114 +/- 36 mm Hg; P = .3) and predischarge (15 +/- 18, 14 +/- 14, and 16 +/- 21 mm Hg; P = .9) maximal left ventricular outflow tract gradients were similar. There were no deaths either in the hospital or at 30 days. At a median follow-up of 166 days (interquartile range, 74-343 days), 21 of 22 patients in group 3 were asymptomatic. One patient in group 3 had a symptomatic left ventricular outflow tract gradient (87 mm Hg) requiring mitral valve replacement. CONCLUSIONS: In patients with hypertrophic cardiomyopathy with bifid hypermobile papillary muscles (even with a basal septal thickness <1.5 cm), papillary muscle reorientation reduces the symptomatic left ventricular outflow tract gradient. Long-term outcomes need to be ascertained.

Cardiac magnetic resonance detection of myocardial scarring in hypertrophic cardiomyopathy: correlation with histopathology and prevalence of ventricular tachycardia.

OBJECTIVES: In hypertrophic cardiomyopathy (HCM) patients undergoing surgical myectomy, we sought to determine the association between pre-operative cardiac magnetic resonance (CMR) findings, small intramural coronary arteriole dysplasia (SICAD) on histopathology, and ventricular tachycardia (VT). BACKGROUND: Myocardial scarring (fibrosis) and SICAD are frequently observed on histopathology in HCM patients. CMR measures wall thickness and detects scar. METHODS: Sixty symptomatic HCM patients (62% men; mean age 51 +/- 14 years), with preserved ejection fraction (mean 64 +/- 5%) and no angiographic coronary disease underwent CMR (cine and delayed post-contrast) using a Siemens 1.5 T scanner, followed by septal myectomy. Maximal basal septal thickness was recorded on cine CMR. Scar was determined (percentage of total myocardium) on delayed post-contrast CMR images and quantified as none, mild (0% to 25%), moderate (26% to 50%), or severe (>50%). VT was assessed using Holter monitoring. Degree of SICAD was determined (normal, mild, moderate, and severe) on histopathology of surgical specimen. RESULTS: SICAD and scar were seen in 45 (75%) and 38 (63%) patients, respectively. In 15 patients without SICAD, 12 (80%) had no scar; 23 (70%) patients with mild SICAD had mild scar on CMR. On multivariate analysis, degree of SICAD was independently associated with scar on CMR (Wald chi-square statistic: 6.8, p < 0.01). Patients with basal septal scar on CMR had higher VT frequency compared with those without (27% vs. 5%, p = 0.03). CONCLUSIONS: A strong association exists between degree of SICAD and myocardial scarring seen on CMR.

Abnormally thickened papillary muscle resulting in dynamic left ventricular outflow tract obstruction: an unusual presentation of hypertrophic cardiomyopathy.

We report the case of a symptomatic 18-year-old patient, gene-positive for hypertrophic cardiomyopathy (HCM), who presented with symptomatic dynamic left ventricular outflow tract (LVOT) obstruction caused by an abnormally thickened papillary muscle in the absence of septal hypertrophy. This was confirmed using multimodality imaging, including echocardiography and magnetic resonance imaging. He successfully underwent surgery for papillary muscle realignment without septal myectomy.

Long-term outcomes in high-risk symptomatic patients with hypertrophic cardiomyopathy undergoing alcohol septal ablation.

OBJECTIVES: We sought to assess outcomes of alcohol septal ablation (ASA) in high-risk patients. BACKGROUND: Because surgical myectomy is the preferred treatment in patients with symptomatic hypertrophic obstructive cardiomyopathy (HOCM) at our institution, we perform ASA in patients who are at high risk for surgery. METHODS: We studied 55 symptomatic HOCM patients (mean age 63 +/- 13 years, 67% women, mean follow-up 8 +/- 1 years), at high risk for surgery (as the result of age/comorbidities) who had ASA between 1997 and 2000. The following were recorded at baseline, 3 months, and 1 year: septal thickness, maximal (resting or provocable) left ventricular outflow tract gradient, Minnesota living with heart failure questionnaire score, and the presence of a permanent pacemaker. All-cause mortality was recorded. RESULTS: No patients died at 48 h, 2 died at 1 year, 7 died at 5 years, and 13 died at 10 years. Only age >65 years at time of ASA predicted long-term mortality (log-rank p = 0.03). Mean maximal left ventricular outflow tract gradient (104 +/- 35 mm Hg vs. 49 +/- 28 mm Hg), septal thickness (2.4 +/- 0.4 cm vs. 1.8 +/- 0.6 cm), and Minnesota living with heart failure score (63 vs. 25) improved at 3 months, compared with baseline (all p < 0.001), with no significant changes at 1 year. New permanent pacemaker was present in 26% of patients. CONCLUSIONS: In symptomatic HOCM patients who are at high risk for surgery, ASA is associated with symptomatic improvement and low short-term mortality; with long-term mortality only associated with older age at time of procedure. In symptomatic HOCM patients at high-risk for surgery, ASA is a viable option.