Signaling Pathways Associated With Prior Cardiovascular Events in Hypertrophic Cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common genetic cardiomyopathy. A subset of patients experience major adverse cardiovascular events (MACEs), including arrhythmias, strokes and heart failure. However, the molecular mechanisms underlying MACEs in HCM are still not well understood. Therefore, we conducted a multicenter case-control study of patients with HCM, comparing those with and without prior histories of MACEs to identify dysregulated signaling pathways through plasma proteomics profiling. METHODS: We performed plasma proteomics profiling of 4986 proteins. We developed a proteomics-based discrimination model in patients enrolled at 1 institution (training set) and externally validated the model in patients enrolled at another institution (test set). We performed pathway analysis of proteins dysregulated in patients with prior MACEs. RESULTS: A total of 402 patients were included, with 278 in the training set and 124 in the test set. In this cohort, 257 (64%) patients had prior MACEs (172 in the training set and 85 in the test set). Using the proteomics-based model from the training set, the area under the receiver operating characteristic curve was 0.82 (95% confidence interval, 0.75-0.90) in the test set. Patients with prior MACEs demonstrated dysregulation in pathways known to be associated with MACEs (eg, TGF-ß) and novel pathways (eg, Ras-MAPK and associated pathways). CONCLUSIONS: In this multicenter study of 402 patients with HCM, we identified both known and novel pathways dysregulated in a subset of patients with more advanced disease.

Evolving Strategies for the Management of Obstructive Hypertrophic Cardiomyopathy.

For many years, treatment of hypertrophic cardiomyopathy (HCM) has focused on non-disease-specific therapies. Cardiac myosin modulators (ie, mavacamten and aficamten) reduce the pathologic actin-myosin interactions that are characteristic of HCM, leading to improved cardiac energetics and reduction in hypercontractility. Several recently published randomized clinical trials have demonstrated that mavacamten improves exercise capacity, left ventricular outflow tract obstruction and symptoms in patients with obstructive HCM and may delay the need for septal-reduction therapy. Long-term data in real-world populations will be needed to fully assess the safety and efficacy of mavacamten. Importantly, HCM is a complex and heterogeneous disease, and not all patients will respond to mavacamten; therefore, careful patient selection and shared decision making will be necessary in guiding the use of mavacamten in obstructive HCM.

Prediction of cardiac death in patients with hypertrophic cardiomyopathy using plasma adipokine levels.

BACKGROUNDS AND AIMS: Hypertrophic cardiomyopathy (HCM) causes cardiac death through both sudden cardiac death (SCD) and death due to heart failure (HF). Although adipokines lead to adverse cardiac remodeling in HCM, the prognostic value of plasma adipokines in HCM remains unknown. We aimed to predict cardiac death in patients with HCM using plasma adipokines. METHODS AND RESULTS: We performed a multicenter prospective cohort study of patients with HCM. The outcome was cardiac death including heart transplant, death due to HF, and SCD. With data from 1 institution (training set), a prediction model was developed using random forest classification algorithm based on 10 plasma adipokines. The performance of the prediction model adjusted for 8 clinical parameters was examined in samples from another institution (test set). Time-to-event analysis was performed in the test set to compare the rate of outcome events between the low-risk and high-risk groups determined by the prediction model. In total, 389 (267 in the training set; 122 in the test set) patients with HCM were included. During the median follow-up of 2.7 years, 21 patients experienced the outcome event. The area under the covariates-adjusted receiver-operating characteristics curve was 0.89 (95 % confidence interval [CI] 0.71-0.99) in the test set. revealed the high-risk group had a significantly higher risk of cardiac death (hazard ratio 17.8, 95 % CI 2.1-148.3, P = 0.008). CONCLUSION: The present multicenter prospective study demonstrated that a panel of plasma adipokines predicts cardiac death in patients with HCM.

Endotyping in Heart Failure　- Identifying Mechanistically Meaningful Subtypes of Disease.

Endotyping is an emerging concept in which diseases are classified into distinct subtypes based on underlying molecular mechanisms. Heart failure (HF) is a complex clinical syndrome that encompasses multiple endotypes with differential risks of adverse events, and varying responses to treatment. Identifying these distinct endotypes requires molecular-level investigation involving multi-"omics" approaches, including genomics, transcriptomics, proteomics, and metabolomics. The derivation of these HF endotypes has important implications in promoting individualized treatment and facilitating more targeted selection of patients for clinical trials, as well as in potentially revealing new pathways of disease that may serve as therapeutic targets. One challenge in the integrated analysis of high-throughput omics and detailed clinical data is that it requires the ability to handle "big data", a task for which machine learning is well suited. In particular, unsupervised machine learning has the ability to uncover novel endotypes of disease in an unbiased approach. In this review, we will discuss recent efforts to identify HF endotypes and cover approaches involving proteomics, transcriptomics, and genomics, with a focus on machine-learning methods.

Effects of Septal Reduction Therapy on Acute Cardiovascular Events and All-Cause Mortality in Patients with Hypertrophic Cardiomyopathy.

Septal reduction therapy (SRT) -i.e. septal myectomy and alcohol septal ablation-has been performed to treat medically refractory hypertrophic cardiomyopathy (HCM) for decades. However, it is largely unknown whether SRT prevents HCM-related cardiovascular events or death. The objective was to examine the effects of SRT on acute cardiovascular events and all-cause mortality in HCM. We performed a propensity score (PS) -matched study using databases that capture all hospitalizations and outpatient visits in New York state. We identified patients with HCM who underwent SRT between 2007 and 2014 (i.e. the SRT group) and those who had never had SRT but had at least one hospitalization for HCM during the same period (i.e. the control group). We performed PS matching at a 1:1 ratio. The primary outcome was a composite of acute cardiovascular events and all-cause mortality during 0-180 days and 181-360 days. The secondary outcome was 180- and 360-day all-cause mortality. We included 846 patients with HCM (423 PS-matched pairs). Patients who underwent SRT had a lower risk of the primary outcome event (0-180 days: odds ratio [OR], 0.54; 95% confidence intervals (CI), 0.37-0.80; P = 0.002 and 181-360 days: OR, 0.33; 95% CI, 0.22-0.51; P < 0.0001). Furthermore, the risk of all-cause mortality was lower at 180 days (OR, 0.37; 95% CI, 0.22-0.63; P = 0.0003) and 360 days post-SRT (OR, 0.32; 95% CI, 0.20-0.51; P < 0.0001). In conclusion, our PS-matched study using population-based datasets demonstrated that SRT was associated with a reduced risk of a composite of acute cardiovascular events and all-cause mortality in HCM during the first post-SRT year.

Antithrombotic strategies after transcatheter aortic valve implantation: Insights from a network meta-analysis.

OBJECTIVES: We aimed to investigate the efficacy and safety of different antithrombotic strategies in patients undergoing transcatheter aortic valve implantation (TAVI) using network meta-analyses. BACKGROUND: Meta-analyses comparing single antiplatelet therapy (SAPT) vs. dual antiplatelet therapy (DAPT), ± oral anticoagulant (OAC) was conducted to determine the appropriate post TAVI antithrombotic regimen. However, there was limited direct comparisons across the different therapeutic strategies. METHODS: MEDLINE and EMBASE were searched through December 2018 to investigate the efficacy and safety of different antithrombotic strategies (SAPT, DAPT, OAC, OAC + SAPT, and OAC + DAPT) in patients undergoing TAVI. The main outcome were all-cause mortality, major or life-threatening bleeding events, and stroke. RESULTS: Our search identified 3 randomized controlled trials and 10 nonrandomized studies, a total of 20,548 patients who underwent TAVI. All OACs were vitamin K antagonists. There was no significant difference on mortality except that OAC + DAPT had significantly higher rates of mortality compared with others (p < .05, I2 = 0%). SAPT had significantly lower rates of bleeding compared with DAPT, OAC+SAPT, and OAC+DAPT (hazard ratio [HR]: 0.59 [0.46-0.77], p < .001, HR: 0.58 [0.34-0.99], p = .045, HR: 0.41 [0.18-0.93], p = .033, respectively, I2 = 0%). There was no significant difference on stroke among all antithrombotic strategies. CONCLUSION: Patients who underwent TAVI had similar all-cause mortality rates among different antithrombotic strategies except OAC+DAPT. Patients on SAPT had significantly lower bleeding risk than those on DAPT, OAC + SAPT, and OAC + DAPT. Our results suggest SAPT is the preferred regimen when there is no indication for DAPT or OAC. When DAPT or OAC is indicated, DAPT + OAC should be avoided.

Myocardial Contraction Fraction Predicts Cardiovascular Events in Patients With Hypertrophic Cardiomyopathy and Normal Ejection Fraction.

BACKGROUND: Myocardial contraction fraction (MCF), the ratio of left ventricular stroke volume to myocardial volume, is a novel parameter that can distinguish between pathologic and physiologic hypertrophy. However, its prognostic value in hypertrophic cardiomyopathy (HCM) has never been examined. The objective was to determine if MCF is associated with functional capacity and predicts adverse cardiovascular outcomes in patients with HCM and normal left ventricular ejection fraction (LVEF). METHODS AND RESULTS: We conducted a prospective cohort study of 137 patients with HCM and LVEF ≥55%. Patients were followed for 2.7 ± 2.5 years. We examined association of MCF with New York Heart Association (NYHA) functional class and a composite outcome of embolic stroke, heart transplantation, and cardiac death. We performed time-to-event analysis with the use of Cox proportional hazards modeling and stepwise elimination. The average age was 52 ± 18 years. The average MCF was 26 ± 11%. MCF was inversely correlated with NYHA functional class (P = .001). A total of 20 subjects experienced an outcome event with an event rate of 5.6% per patient-year. MCF independently predicted the outcome (adjusted hazard ratio 0.50 per 10% increase, 95% confidence interval 0.28-0.90, adjusted P = .02). CONCLUSIONS: In patients with HCM and normal LVEF, MCF is associated with functional capacity and independently predicts adverse cardiovascular outcomes.

Incidence of Acute Cardiovascular Event After Acute Exacerbation of COPD.

BACKGROUND: There is a lack of comprehensive view of the association between acute exacerbation of COPD (AECOPD) and the risk of acute cardiovascular events. OBJECTIVE: To determine the association of AECOPD with 30-day and 1-year incidences of acute cardiovascular event. DESIGN: Self-controlled case series analysis using population-based datasets from three US states from 2005 through 2011. PARTICIPANTS: Patients aged ≥ 40 years with AECOPD. MAIN MEASURES: The primary outcome was a composite of an ED visit or hospitalization for acute cardiovascular events, including acute myocardial infarction, heart failure, atrial fibrillation, pulmonary embolism, and stroke. We compared the incidence of each patient's acute cardiovascular event during the first 30-day period before the index AECOPD (30-day reference period) in comparison with that during the 30-day period after the index AECOPD. Likewise, with the 1-year period before the index AECOPD as reference, we also estimated incidence rate ratios (IRRs) for each patient's outcomes during 1-year period after the index AECOPD. KEY RESULTS: Overall, there were 362,867 patients with an ED visit or hospitalization for AECOPD. Compared with the 30-day reference period, the incidence of acute cardiovascular event in the 30-day period after the AECOPD was significantly higher (IRR, 1.34; 95%CI, 1.30-1.39; P < 0.001). Likewise, compared with the 1-year reference period, the incidence during the 1-year period after the AECOPD was also higher (IRR, 1.20; 95%CI, 1.18-1.22; P < 0.001). For each of acute cardiovascular conditions, the associations remained significant (all P < 0.05). CONCLUSIONS: AECOPD was associated with increased 30-day and 1-year incidences of acute cardiovascular event.

Clinical Correlates and Prognostic Value of Elevated Right Atrial Pressure in Patients With Hypertrophic Cardiomyopathy.

BACKGROUND: The clinical characteristics associated with elevated right atrial pressure (RAP) in hypertrophic cardiomyopathy (HCM) are unknown. Few data exist as to whether elevated RAP has prognostic implications in patients with HCM. This study investigated the clinical correlates and prognostic value of elevated RAP in HCM.Methods and Results:This retrospective cohort study was performed on 180 patients with HCM who underwent right heart catheterization between 1997 and 2014. Elevated RAP was defined as >8 mmHg. Baseline characteristics, mean pulmonary artery pressure, and mean pulmonary capillary wedge pressure (PCWP) were assessed for association with elevated RAP. The predictive value of elevated RAP for all-cause mortality and the development of atrial fibrillation (AF), ventricular tachycardia/fibrillation (VT/VF), and stroke was evaluated. Elevated RAP was associated with higher New York Heart Association class, dyspnea on exertion, orthopnea, edema, jugular venous distention, larger left atrial size, right ventricular hypertrophy, higher pulmonary artery pressure, and higher PCWP. RAP independently predicted all-cause mortality (adjusted hazard ratio [aHR] 2.18 per 5-mmHg increase, 95% confidence interval [CI] 1.05-4.50, P=0.04) and incident AF (aHR 1.85 per 5-mmHg increase, 95% CI 1.20-2.85, P=0.005). Elevated RAP did not predict VT/VF (P=0.36) or stroke (P=0.28). CONCLUSIONS: Elevated RAP in patients with HCM is associated with left-sided heart failure and is an independent predictor of all-cause mortality and new-onset AF.

Association of bariatric surgery with risk of acute care use for hypertension-related disease in obese adults: population-based self-controlled case series study.

BACKGROUND: Hypertension carries a large societal burden. Obesity is known as a risk factor for hypertension. However, little is known as to whether weight loss interventions reduce the risk of hypertension-related adverse events, such as acute care use (emergency department [ED] visit and/or unplanned hospitalization). We used bariatric surgery as an instrument for investigating the effect of large weight reduction on the risk of acute care use for hypertension-related disease in obese adults with hypertension. METHODS: We performed a self-controlled case series study of obese patients with hypertension who underwent bariatric surgery using population-based ED and inpatient databases that recorded every bariatric surgery, ED visit, and hospitalization in three states (California, Florida, and Nebraska) from 2005 to 2011. The primary outcome was acute care use for hypertension-related disease. We used conditional logistic regression to compare each patient's risk of the outcome event during sequential 12-month periods, using pre-surgery months 13-24 as the reference period. RESULTS: We identified 980 obese patients with hypertension who underwent bariatric surgery. The median age was 48 years (interquartile range, 40-56 years), 74% were female, and 55% were non-Hispanic white. During the reference period, 17.8% (95% confidence interval [CI], 15.4-20.2%) had a primary outcome event. The risk remained unchanged in the subsequent 12-month pre-surgery period (18.2% [95% CI, 15.7-20.6%]; adjusted odds ratio [aOR] 1.02 [95% CI, 0.83-1.27]; P = 0.83). In the first 12-month period after bariatric surgery, the risk significantly decreased (10.5% [8.6-12.4%]; aOR 0.58 [95% CI, 0.45-0.74]; P < 0.0001). Similarly, the risk remained significantly reduced in the 13-24 months after bariatric surgery (12.9% [95% CI, 10.8-15.0%]; aOR 0.71 [95% CI, 0.57-0.90]; P = 0.005). By contrast, there was no significant reduction in the risk among obese patients who underwent non-bariatric surgery (i.e., cholecystectomy, hysterectomy, spinal fusion, or mastectomy). CONCLUSIONS: In this population-based study of obese adults with hypertension, we found that the risk of acute care use for hypertension-related disease decreased by 40% after bariatric surgery. The data provide the best evidence on the effectiveness of substantial weight loss on hypertension-related morbidities, underscoring the importance of discussing options for weight reduction when treating obese patients with hypertension.

Impact of glycoprotein IIb/IIIa inhibitors on the efficacy and safety of ticagrelor compared with clopidogrel in patients with acute coronary syndromes: Analysis from the Platelet Inhibition and Patient Outcomes (PLATO) Trial.

BACKGROUND: Ticagrelor reduced cardiovascular events compared with clopidogrel in PLATO without increasing overall major bleeding. We evaluated whether the use of glycoprotein IIb/IIIa inhibitor (GPI) impacts the relative efficacy and safety of ticagrelor compared with clopidogrel. METHODS: PLATO randomized 18,624 subjects with acute coronary syndrome to ticagrelor versus clopidogrel. The primary efficacy end point was cardiovascular death/myocardial infarction/stroke, and the primary safety end point was major bleeding. The use of GPI was at the physician's discretion and open-label. We evaluated outcomes at 30 days stratified by GPI use in the subgroup of 9,983 patients who underwent percutaneous coronary intervention (PCI) within 72 hours. RESULTS: A total of 4,020 (40%) received a GPI. Those receiving a GPI were more likely to be younger, be male, and undergo multivessel PCI. There was no interaction between treatment and GPI use for the primary efficacy and safety end points. Patients treated without GPI had a lower rate of definite stent thrombosis and higher rate of minor/major bleeding with ticagrelor compared with clopidogrel (P < .05), whereas there was no such difference with GPI (P interaction < .05). CONCLUSIONS: In patients with acute coronary syndrome undergoing early PCI, the efficacy and safety of ticagrelor as compared with clopidogrel were not modified by GPI use according to the primary efficacy and safety end point of the trial, although there were indications of greater benefit on definite stent thrombosis and more major or minor bleeding with ticagrelor in patients without (vs with) GPI treatment.

Ischemic cardiac outcomes and hospitalizations according to prior macrovascular disease status in patients with type 2 diabetes and recent acute coronary syndrome from the Examination of Cardiovascular Outcomes with Alogliptin versus Standard of Care trial.

BACKGROUND: Concerns raised regarding adverse cardiovascular (CV) outcomes with new therapies for type 2 diabetes mellitus (T2DM) have led to several large-scale CV outcome trials. The EXAMINE trial confirmed noninferiority of the dipeptidyl dipeptidase 4 inhibitor alogliptin to placebo on major adverse cardiac event rates in a post-acute coronary syndrome (ACS) T2DM population. We present data on additional ischemic cardiac events and CV hospitalizations in EXAMINE. METHODS: Patients with T2DM and an ACS event in the previous 15 to 90 days were randomly assigned to alogliptin or placebo on a background of standard treatment for diabetes. The incident rates of a 5-component composite end point of CV death, stroke, myocardial infarction, unstable angina, and coronary revascularization as well as CV hospitalization were calculated in all participants and according to macrovascular disease at baseline. RESULTS: There were no significant differences between alogliptin (n = 2,701) and placebo (n = 2,679) in the event rate of the 5-component composite endpoint with median follow-up 533 days (21.0% vs 21.5%, hazard ratio [HR] 0.98 [0.87-1.10], P = .72). No differences were observed in terms of CV hospitalization (25.0% vs 25.4%, HR 0.98 [0.88-1.09], P = .70) or coronary revascularization (10.6% vs 10.2%, HR 1.05 [0.88-1.09], P = .60). No interactions were observed for treatment and prior macrovascular disease. CONCLUSIONS: EXAMINE demonstrates that there was no increase in the risk of cardiac ischemic events and CV hospitalizations with alogliptin in a high-risk post-ACS patient population. Because these are major driver of overall health care costs, these data suggest that there would be no adverse impact on health care resource utilization.

Edoxaban vs. Warfarin in East Asian Patients With Atrial Fibrillation　- An ENGAGE AF-TIMI 48 Subanalysis.

BACKGROUND: In the multinational, double-blind, double-dummy ENGAGE AF-TIMI 48 phase 3 study, once-daily edoxaban was non-inferior to warfarin for prevention of stroke or systemic embolism event (SEE) in patients with non-valvular atrial fibrillation (AF). Here, we evaluated the efficacy and safety of edoxaban in patients from East Asia. METHODS AND RESULTS: Patients aged ≥21 years with documented AF and CHADS score ≥2 were randomized to receive once-daily edoxaban higher-dose (60 mg) or lower-dose (30 mg) regimen or warfarin dose-adjusted to an international normalized ratio of 2.0-3.0. Patients with a creatinine clearance of 30-50 ml/min, weighing ≤60 kg, or receiving strong p-glycoprotein inhibitors at randomization or during the study received a 50% dose reduction of edoxaban or matched placebo. This prespecified subanalysis included 1,943 patients from Japan, China, Taiwan, and South Korea. The annualized rate of stroke/SEE for higher-dose edoxaban was 1.34% vs. 2.62% for warfarin (hazard ratio [HR], 0.53; 95% confidence interval [CI]: 0.31-0.90, P=0.02) and 2.52% for lower-dose edoxaban (HR, 0.98; 95% CI: 0.63-1.54, P=0.93). Compared with warfarin (4.80%), major bleeding was significantly reduced for the higher-dose (2.86%; HR, 0.61; 95% CI: 0.41-0.89, P=0.011) and lower-dose regimens (1.59%; HR, 0.34; 95% CI: 0.21-0.54, P<0.001). CONCLUSIONS: Once-daily edoxaban provided similar efficacy to warfarin while reducing major bleeding risk in the East Asian population.

PCSK9 (Proprotein convertase subtilisin/kexin type 9) inhibitors: past, present, and the future.

Reduction in low-density lipoprotein cholesterol (LDL-C), mainly with statins, has decreased the risk of cardiovascular events over the last few decades. However, there are several patient populations that warrant further decrease in LDL-C by additional cholesterol-lowering therapy other than statins. Proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors are a new class of drugs that have been shown to further decrease LDL-C by 50-70% when administered as a monotherapy or on a background therapy with statins. Proprotein convertase subtilisin/kexin type 9 inhibitors are also an excellent example of drug development in which discovery of gene mutations and its clinical effects have rapidly progressed into successful preclinical and clinical studies with multiple Phases 1-3 clinical trials completed or ongoing to date. This review summarizes the rapid evolution of the drug from genetic discovery to identification of targets for the drugs, to animal and human testing, and to large clinical outcomes trials, followed by discussion on foreseeable challenges of PCSK9 inhibitors.

Effects of Regional Differences in Asia on Efficacy and Safety of Edoxaban Compared With Warfarin--Insights From the ENGAGE AF-TIMI 48 Trial.

BACKGROUND: In 21,105 patients with atrial fibrillation in the ENGAGE AF-TIMI 48 trial, edoxaban was non-inferior to warfarin in preventing thromboembolic events while reducing bleeding. We compared results in Japan with the rest of East Asia (EA), including China, Korea, and Taiwan. METHODS AND RESULTS: We compared baseline characteristics, time-in-therapeutic range (TTR) for warfarin, and outcomes (efficacy: stroke or systemic embolic events [SEE], safety: major bleeding). Interaction P values were used to assess for effect modification of treatment (higher-dose edoxaban [HDE, 60 mg/30 mg] vs. warfarin; lower-dose edoxaban [LDE, 30 mg/15 mg] vs. warfarin) by region with adjustments for baseline characteristics. Fewer patients in Japan (n=1,010) were female, taking aspirin or amiodarone, naïve to warfarin (P<0.001 for each), had a history of stroke or transient ischemic attack (P=0.02), and more patients needed dose reduction (P<0.001) compared with EA (n=933). The mean TTR was higher in Japan (70% vs. 56%, P<0.001). Evidence for statistical interactions was observed for HDE vs. warfarin by region for stroke/SEE (adjusted P-int=0.052) and major bleeding (adjusted P-int=0.048) with greater relative efficacy and safety with HDE in EA compared with Japan. No interactions were observed for LDE vs. warfarin after adjustment. CONCLUSIONS: HDE had a greater relative efficacy and safety in EA compared with Japan that was only partially explained by differences in baseline characteristics and TTR.

Cardiac I-1c overexpression with reengineered AAV improves cardiac function in swine ischemic heart failure.

Cardiac gene therapy has emerged as a promising option to treat advanced heart failure (HF). Advances in molecular biology and gene targeting approaches are offering further novel options for genetic manipulation of the cardiovascular system. The aim of this study was to improve cardiac function in chronic HF by overexpressing constitutively active inhibitor-1 (I-1c) using a novel cardiotropic vector generated by capsid reengineering of adeno-associated virus (BNP116). One month after a large anterior myocardial infarction, 20 Yorkshire pigs randomly received intracoronary injection of either high-dose BNP116.I-1c (1.0 × 10(13) vector genomes (vg), n = 7), low-dose BNP116.I-1c (3.0 × 10(12) vg, n = 7), or saline (n = 6). Compared to baseline, mean left ventricular ejection fraction increased by 5.7% in the high-dose group, and by 5.2% in the low-dose group, whereas it decreased by 7% in the saline group. Additionally, preload-recruitable stroke work obtained from pressure-volume analysis demonstrated significantly higher cardiac performance in the high-dose group. Likewise, other hemodynamic parameters, including stroke volume and contractility index indicated improved cardiac function after the I-1c gene transfer. Furthermore, BNP116 showed a favorable gene expression pattern for targeting the heart. In summary, I-1c overexpression using BNP116 improves cardiac function in a clinically relevant model of ischemic HF.

Mitral regurgitation mechanisms related to systolic anterior motion in hypertrophic cardiomyopathy.

Background: Systolic anterior motion (SAM) of the mitral valve can result in mitral regurgitation (MR) and adverse outcomes in patients with obstructive hypertrophic cardiomyopathy (HCM). However, the mechanism and characteristics of MR severity mediated by SAM are unresolved. This study aimed to elucidate the anatomic and hemodynamic associations of MR and the impact of septal myectomy on changes in MR severity in patients with HCM. Methods: We retrospectively reviewed patients who underwent septal myectomy with SAM and interpretable imaging between 2017-2022. Significant MR was defined as moderate or more MR. The mitral valve, papillary muscle, and left ventricular geometry were quantitatively evaluated via echocardiography and cardiac computed tomography. Results: Out of 34 patients, two groups were identified: those with preoperative significant MR (n=16) and those without significant MR (n=18). Patients with significant preoperative MR exhibited worse heart failure symptoms at baseline than those without. Following myectomy, these patients showed higher residual left ventricular outflow tract (LVOT) gradients at rest and with provocative measures than those without preoperative MR. Multivariate regression analysis revealed a significant association between the tenting area and MR severity. Additionally, the chordal cutting procedure alleviated the tenting area [2.1 (1.8-2.6) vs. 1.4 (1.2-1.6) cm2] compared to those without it. Conclusions: Our preliminary data suggested that chordal cutting with septal myectomy was associated with an improvement in the tenting area, contributing to MR severity. This procedure may serve as an effective therapy for patients with SAM and significant MR.

Mortality After Alcohol Septal Ablation vs. Septal Myectomy in Patients With Obstructive Hypertrophic Cardiomyopathy.

Background: Alcohol septal ablation (ASA) and septal myectomy (SM) are 2 options for septal reduction therapy (SRT) to treat medication-resistant symptomatic obstructive hypertrophic cardiomyopathy (HCM). Because differences in mortality rates after these different SRT methods have not been extensively investigated in real-world settings, in this study compared the 1-year mortality rates after ASA and SM using population-based database. Methods and Results: Utilizing New York Statewide Planning and Research Cooperative System (SPARCS) data from 2005 to 2016, we performed a comparative effectiveness study of ASA vs. SM in patients with HCM. The outcome was all-cause death up to 360 days after SRT. We constructed a multivariable logistic regression model and performed sensitivity analysis with propensity score (PS)-matching and inverse probability of treatment weighting (IPTW) methods. We identified 755 patients with HCM who underwent SRT: 348 with ASA and 407 with SM. The multivariable analysis showed that all-cause deaths were significantly fewer in the ASA group at 360 days after SRT (adjusted odds ratio=0.34; 95% confidence interval [CI] 0.13-0.84; P=0.02). The PS-matching and IPTW methods also supported a lower mortality rate in the ASA group at 360 days post-SRT. Conclusions: In this population-based study of patients with HCM who underwent SRT in a real-world setting, the 1-year all-cause mortality rate was significantly lower in patients who underwent ASA compared with SM.

Emerging antithrombotic drugs for acute coronary syndrome.

INTRODUCTION: Acute coronary syndrome (ACS) encompasses acute myocardial infarction (MI) and unstable angina. Activation of platelets and coagulation cascade plays a central role in the development of ACS. Over the past decade, there have been substantial improvements in the strategies for secondary prevention of ACS, including the development of more potent oral antiplatelet agents such as prasugrel and ticagrelor. However, therapies with even better efficacy and safety profiles and more rapid onset and offset of action would be desirable. AREAS COVERED: This review discusses the advantages and disadvantages of the currently available antithrombotic agents and describes the findings from recent clinical trials of three novel agents; cangrelor (an intravenous P2Y12 receptor antagonist), vorapaxar (protease-activated receptor-1 inhibitor) and rivaroxaban (an oral factor Xa inhibitor). EXPERT OPINION: Cangrelor appears more promising than clopidogrel when a very rapid onset and reversal of antiplatelet effect is needed. Vorapaxar in addition to standard oral antiplatelet therapy was effective in patients with prior MI, but was not safe in patients with a prior stroke. Low dose rivaroxaban decreased cardiovascular events and mortality in patients post-ACS compared to placebo, although bleeding was increased.