Distal Versus Conventional Radial Access for Coronary Angiography and Intervention: The DISCO RADIAL Trial

BackgroundCurrently, transradial access (TRA) is the recommended access for coronary procedures because of increased safety, with radial artery occlusion (RAO) being its most frequent complication, which will increasingly affect patients undergoing multiple procedures during their lifetimes. Recently, distal radial access (DRA) has emerged as a promising alternative access to minimize RAO risk. A large-scale, international, randomized trial comparing RAO with TRA and DRA is lacking.ObjectivesThe aim of this study was to assess the superiority of DRA compared with conventional TRA with respect to forearm RAO.MethodsDISCO RADIAL (Distal vs Conventional Radial Access) was an international, multicenter, randomized controlled trial in which patients with indications for percutaneous coronary procedure using a 6-F Slender sheath were randomized to DRA or TRA with systematic implementation of best practices to reduce RAO. The primary endpoint was the incidence of forearm RAO assessed by vascular ultrasound at discharge. Secondary endpoints include crossover, hemostasis time, and access site–related complications.ResultsOverall, 657 patients underwent TRA, and 650 patients underwent DRA. Forearm RAO did not differ between groups (0.91% vs 0.31%; P = 0.29). Patent hemostasis was achieved in 94.4% of TRA patients. Crossover rates were higher with DRA (3.5% vs 7.4%; P = 0.002), and median hemostasis time was shorter (180 vs 153 minutes; P < 0.001). Radial artery spasm occurred more with DRA (2.7% vs 5.4%; P = 0.015). Overall bleeding events and vascular complications did not differ between groups.ConclusionsWith the implementation of a rigorous hemostasis protocol, DRA and TRA have equally low RAO rates. DRA is associated with a higher crossover rate but a shorter hemostasis time.     

Distal vs Conventional Radial Access for Coronary Angiography and/or Intervention: A Meta-Analysis of Randomized Trials

BackgroundEmerging evidence from randomized clinical trials (RCTs) comparing distal radial access (DRA) with conventional radial access (RA) is available.ObjectivesThe aim of this study was to provide a quantitative appraisal of the effects of DRA) vs conventional RA for coronary angiography with or without intervention.MethodsThe PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov databases were searched for RCT comparing DRA vs conventional RA for coronary angiography and/or intervention. Data were pooled by meta-analysis using a random-effects model. The primary endpoint was radial artery occlusion (RAO) at the longest available follow-up.ResultsFourteen studies enrolling 6,208 participants were included. Compared with conventional RA, DRA was associated with a significant lower risk of RAO, either detected at latest follow-up (risk ratio [RR]: 0.36; 95% CI: 0.23-0.56; P < 0.001; number needed to treat [NNT] = 30) or in-hospital (RR: 0.32; 95% CI: 0.19-0.53; P < 0.001; NNT = 28), as well as EASY (Early Discharge After Transradial Stenting of Coronary Arteries) ≥II hematoma (RR: 0.51; 95% CI: 0.27-0.96; P = 0.04; NNT = 107). By contrast, DRA was associated with a higher risk of access site crossover (RR: 3.08; 95% CI: 1.88-5.06; P < 0.001; NNT = 12), a longer time for radial puncture (standardized mean difference [SMD]: 3.56; 95% CI: 0.96-6.16; P < 0.001), a longer time for sheath insertion (SMD: 0.37; 95% CI: 0.16-0.58; P < 0.001), and a higher number of puncture attempts (SMD: 0.59, 95% CI: 0.48-0.69; P < 0.001).ConclusionsCompared with conventional RA, DRA is associated with lower risks of RAO and EASY ≥II hematoma but requires longer time for radial artery cannulation and sheath insertion, more puncture attempts, and a higher access site crossover.     

Effect of Immunosuppressive Therapy and Biopsy Status in Monitoring Therapy Response in Suspected Cardiac Sarcoidosis

BackgroundPatients with suspected cardiac sarcoidosis frequently undergo fluorodeoxyglucose (FDG)–positron emission tomography (PET)/computed tomography (CT) imaging to assess disease activity at baseline and after treatment initiation.ObjectivesThis study investigated the effect of immunosuppressive therapy and biopsy status to achieve complete treatment response (CTR), partial treatment response (PTR), or no response (NR) on myocardial FDG-PET/CT.MethodsThis study analyzed 83 patients with suspected cardiac sarcoidosis (aged 53 ± 1.8 years, 71% were male, 69% were White, 61% had a history of biopsy-confirmed sarcoidosis) who were treatment naive, had evidence of myocardial FDG at baseline, and underwent repeat PET imaging after treatment initiation. CTR was graded visually, and PTR/NR were measured both visually and quantitatively using the total glycolytic activity. Patients were also evaluated for the occurrence of death, sustained ventricular arrhythmias, and heart failure admissions.ResultsOverall, 59 patients (71%) achieved CTR/PTR (30%/41%) at follow-up scan (P = 0.04). Total glycolytic activity and visual estimate of PTR/NR had excellent agreement (κ = 0.86 [95% CI: 0.72-0.99]; P < 0.0001). In patients receiving prednisone only, the highest rates of CTR/PTR were observed in patients initiated on moderate or high dose (P < 0.01). In a regression model, moderate prednisone start dose (P = 0.03) was more strongly associated with achieving CTR/PTR than was high prednisone start dose. However, the latter patients were tapered faster between start dose and follow-up scan (P < 0.01). After a median follow-up of 4.7 (IQR: 3.1-7.8) years, patients who were biopsy-proven (vs non-biopsy-proven; P = 0.029) and with preserved left ventricular function (P = 002) were less likely to experience major adverse cardiac events. Outcomes based on treatment response status (CTR vs PTR vs NR; P = 0.23) were not significantly different.ConclusionsAmong patients with suspected sarcoidosis and evidence of myocardial inflammation, treatment response by serial FDG-PET was variable, but a favorable response was more common when using moderate-to-high intensity prednisone dose. Biopsy-proven individuals and those with preserved systolic function were less likely to experience adverse outcomes during follow-up.     

Evolution of Myocardial Tissue Injury: A CMR Study Over a Decade After STEMI

BackgroundIn patients with a first ST-segment elevation myocardial infarction (STEMI), the multi-annual evolution of myocardial tissue injury parameters, as assessed by cardiac magnetic resonance (CMR), has not yet been described.ObjectivesThis study examined myocardial tissue injury dynamics over a decade after STEMI.MethodsSequential CMR examinations (within the first week after STEMI, and at 4, 12, months, and 9 years thereafter) were conducted in 74 patients with STEMI treated with primary percutaneous coronary intervention. Left ventricular function, infarct size (IS), and microvascular obstruction (MVO) were assessed at all time points. T21, T2, and T1 mapping (n = 59) were added at 9-year scan to evaluate the presence of iron and edema within the infarct core, respectively.ResultsIS decreased progressively and significantly between all CMR time points (all P < 0.001), with an average reduction rate of 5.8% per year (IQR: 3.5%-8.8%) and a relative reduction of 49% (IQR: 39%-76%) over a decade. MVO was present in 61% of patients at baseline, but was not present at the follow-up examinations. At 9-year CMR, 17 of 59 (29%) patients showed iron deposition within the infarct core, whereas 82% had persistent edema. Persistent iron and edema were associated with greater IS on any occasion (all P < 0.001), as well as the presence of MVO (P < 0.001). Patients with persistent iron and edema showed a lower relative regression of IS (P = 0.005 and P = 0.032, respectively) and greater end-systolic volumes over a decade (all P < 0.012 and P > 0.023, respectively). A T1 hypointense infarct core without evidence of T21 iron deposition (14 of 59 [24%] patients) was attributed to lipomatous metaplasia of the infarct.ConclusionsThe evolution of IS is a dynamic process that extends well beyond the first few months after STEMI. Persistence of iron and edema within the infarct core occurs up to a decade after STEMI and is associated with initial infarct severity and poor infarct healing.     

Aortic Stenosis Progression: A Systematic Review and Meta-Analysis

BackgroundAortic valve stenosis is a progressive disorder with variable progression rates. The factors affecting aortic stenosis (AS) progression remain largely unknown.ObjectivesThis systematic review and meta-analysis sought to determine AS progression rates and to assess the impact of baseline AS severity and sex on disease progression.MethodsThe authors searched Medline, Embase, and the Cochrane Central Register of Controlled Trials from inception to July 1, 2020, for prospective studies evaluating the progression of AS with the use of echocardiography (mean gradient [MG], peak velocity [PV], peak gradient [PG], or aortic valve area [AVA]) or computed tomography (calcium score [AVC]). Random-effects meta-analysis was performed to evaluate the rate of AS progression for each parameter stratified by baseline severity, and meta-regression was performed to determine the impact of baseline severity and of sex on AS progression rate.ResultsA total of 24 studies including 5,450 patients (40% female) met inclusion criteria. The pooled annualized progression of MG was +4.10 mm Hg (95% CI: 2.80-5.41 mm Hg), AVA −0.08 cm² (95% CI: 0.06-0.10 cm²), PV +0.19 m/s (95% CI: 0.13-0.24 m/s), PG +7.86 mm Hg (95% CI: 4.98-10.75 mm Hg), and AVC +158.5 AU (95% CI: 55.0-261.9 AU). Increasing baseline severity of AS was predictive of higher rates of progression for MG (P < 0.001), PV (P = 0.001), and AVC (P < 0.001), but not AVA (P = 0.34) or PG (P = 0.21). Only 4 studies reported AS progression stratified by sex, with only PV and AVC having 3 studies to perform a meta-analysis. No difference between sex was observed for PV (P = 0.397) or AVC (P = 0.572), but the level of confidence was low.ConclusionsThis study provides progression rates for both hemodynamic and anatomic parameters of AS and shows that increasing hemodynamic and anatomic baseline severity is associated with faster AS progression. More studies are needed to determine if sex differences affect AS progression. (Aortic Valve Stenosis Progression Rate: A Systematic Review and Meta-Analysis; CRD42021207726)     

The REPAIR Study: Effects of Macitentan on RV Structure and Function in Pulmonary Arterial Hypertension

ObjectivesThe REPAIR (Right vEntricular remodeling in Pulmonary ArterIal hypeRtension) study evaluated the effect of macitentan on right ventricular (RV) and hemodynamic outcomes in patients with pulmonary arterial hypertension (PAH), using cardiac magnetic resonance (CMR) and right heart catheterization (RHC).BackgroundRV failure is the primary cause of death in PAH. CMR is regarded as the most accurate noninvasive method for assessing RV function and remodeling and CMR measures of RV function and structure are strongly prognostic for survival in patients with PAH. Despite this, CMR is not routinely used in PAH clinical trials.MethodsREPAIR was a 52-week, open-label, single-arm, multicenter, phase 4 study evaluating the effect of macitentan 10 mg, with or without phosphodiesterase type-5 inhibition, on RV remodeling and function and cardiopulmonary hemodynamics. Primary endpoints were change from baseline to week 26 in RV stroke volume, determined by CMR; and pulmonary vascular resistance, determined by RHC. Efficacy measures were assessed for all patients with baseline and week 26 data for both primary endpoints.ResultsAt a prespecified interim analysis in 42 patients, both primary endpoints were met, enrollment was stopped, and the study was declared positive. At final analysis (n = 71), RV stroke volume increased by 12 mL (96% confidence level: 8.4-15.6 mL; P < 0.0001) and pulmonary vascular resistance decreased by 38% (99% confidence level: 31%-44%; P < 0.0001) at week 26. Significant positive changes were also observed in secondary and exploratory CMR (RV and left ventricular), hemodynamic, and functional endpoints at week 26. Improvements in CMR RV and left ventricular variables and functional parameters were maintained at week 52. Safety (n = 87) was consistent with previous clinical trials.ConclusionsIn the context of this study, macitentan treatment in patients with PAH resulted in significant and clinically-relevant improvements in RV function and structure and cardiopulmonary hemodynamics. At 52 weeks, improvements in RV function and structure were sustained. (REPAIR: Right vEntricular remodeling in Pulmonary ArterIal hypeRtension [REPAIR]; NCT02310672)     

Too Little of a Good Thing: Strong Associations Between Cardiac Size and Fitness Among Women

BackgroundCardiorespiratory fitness (CRF) is associated with functional impairment and cardiac events, particularly heart failure (HF). However, the factors predisposing women to low CRF and HF remain unclear.ObjectivesThis study sought to evaluate the association between CRF and measures of ventricular size and function and to examine the potential mechanism linking these factors.MethodsA total of 185 healthy women aged >30 years (51 ± 9 years) underwent assessment of CRF (peak volume of oxygen uptake [Vo₂peak]) and biventricular volumes at rest and during exercise by using cardiac magnetic resonance (CMR). The relationships among Vo₂peak, cardiac volumes, and echocardiographic measures of systolic and diastolic function were assessed using linear regression. The effect of cardiac size on cardiac reserve (change in cardiac function during exercise) was assessed by comparing quartiles of resting left ventricular end-diastolic volume (LVEDV).ResultsVo₂peak was strongly associated with resting measures of LVEDV and right ventricular end-diastolic volume (R² = 0.58-0.63; P < 0.0001), but weakly associated with measures of resting left ventricular (LV) systolic and diastolic function (R² = 0.01-0.06; P < 0.05). Increasing LVEDV quartiles were positively associated with cardiac reserve, with the smallest quartile showing the smallest reduction in LV end-systolic volume (quartile [Q]1: −4 mL vs Q4: −12 mL), smallest augmentation in LV stroke volume (Q1: +11 mL vs Q4: +20 mL) and cardiac output (Q1: +6.6 L/min vs Q4: +10.3 L/min) during exercise (interaction P < 0.001 for all).ConclusionsA small ventricle is strongly associated with low CRF because of the combined effect of a smaller resting stroke volume and an attenuated capacity to increase with exercise. The prognostic implications of low CRF in midlife highlight the need for further longitudinal studies to determine whether women with small ventricles are predisposed to functional impairment, exertional intolerance, and HF later in life.     

Distal or Traditional Transradial Access Site for Coronary Procedures: A Single-Center,Randomized Study

ObjectivesThis study aimed to compare the efficacy and safety of the distal transradial approach (dTRA) versus the conventional transradial approach (TRA) for coronary angiography and percutaneous coronary interventions.BackgroundThe recommended approach for coronary procedures is TRA. However, it is associated with radial artery occlusion (RAO). The dTRA could potentially decrease the incidence of RAO.MethodsOne thousand forty-two consecutive patients were randomized (1:1) to right dTRA or TRA. The primary endpoint was the rate of RAO, which was evaluated by Doppler ultrasound at 60 days after randomization.ResultsFive hundred eighteen and 524 patients were randomized to dTRA and TRA, respectively. Follow-up Doppler evaluation of the radial artery was accomplished in 404 (78.0%) patients in the dTRA group and 392 (74.8%) in the TRA group. The rate of RAO was significantly reduced in the dTRA group compared with TRA group (3.7% vs 7.9%, respectively; P = 0.014). The rate of successful sheath insertion was lower in the dTRA group compared with the TRA group (78.7% vs 94.8%, respectively; P < 0.001). More punctures (median = 2 [IQR: 1-3] vs median = 1 [IQR: 1-2]; P < 0.001) and a longer time (120 vs 75 seconds; P < 0.001) were required for sheath insertion in the dTRA group compared with the TRA group. The hemostasis time was shorter in the dTRA group compared with the TRA group (60 vs 120 minutes; P < 0.001). The dose area product was higher in the dTRA group (median = 32,729 in the dTRA vs 28,909 cGy/cm² in the TRA group; P = 0.02). No significant differences were observed in the secondary safety endpoints (bleeding [Bleeding Academic Research Consortium ≥2] and severe radial artery spasm).ConclusionsAccording to our study, dTRA was associated with a lower rate of forearm RAO, a shorter time of hemostasis, a higher crossover rate and dose area product, and a longer procedural time compared with TRA.     

Myocardial Contractile Mechanics in Ischemic Mitral Regurgitation: Multicenter Data Using Stress Perfusion Cardiovascular Magnetic Resonance

BackgroundLeft ventricular (LV) ischemia has been variably associated with functional mitral regurgitation (FMR). Determinants of FMR in patients with ischemia are poorly understood.ObjectivesThis study sought to test whether contractile mechanics in ischemic myocardium underlying the mitral valve have an impact on likelihood of FMR.MethodsVasodilator stress perfusion cardiac magnetic resonance was performed in patients with coronary artery disease (CAD) at multiple centers. FMR severity was confirmed quantitatively via core lab analysis. To test relationship of contractile mechanics with ischemic FMR, regional wall motion and strain were assessed in patients with inducible ischemia and minimal (≤5% LV myocardium, nontransmural) infarction.ResultsA total of 2,647 patients with CAD were studied; 34% had FMR (7% moderate or greater). FMR severity increased with presence (P < 0.001) and extent (P = 0.01) of subpapillary ischemia: patients with moderate or greater FMR had more subpapillary ischemia (odds ratio [OR]: 1.13 per 10% LV; 95% CI: 1.05-1.21; P = 0.001) independent of ischemia in remote regions (P = NS); moderate or greater FMR prevalence increased stepwise with extent of ischemia and infarction in subpapillary myocardium (P < 0.001); stronger associations between FMR and infarction paralleled greater wall motion scores in infarct-affected territories. Among patients with inducible ischemia and minimal infarction (n = 532), wall motion and radial strain analysis showed impaired subpapillary contractile mechanics to associate with moderate or greater FMR (P < 0.05) independent of remote regions (P = NS). Conversely, subpapillary ischemia without contractile dysfunction did not augment FMR likelihood. Mitral and interpapillary dimensions increased with subpapillary radial strain impairment; each remodeling parameter associated with impaired subpapillary strain (P < 0.05) independent of remote strain (P = NS). Subpapillary radial strain (OR: 1.13 per 5% [95% CI: 1.02-1.25]; P = 0.02) and mitral tenting area (OR: 1.05 per 10 mm² [95% CI: 1.00-1.10]; P = 0.04) were associated with moderate or greater FMR controlling for global remodeling represented by LV end-systolic volume (P = NS): when substituting sphericity for LV volume, moderate or greater FMR remained independently associated with subpapillary radial strain impairment (OR: 1.22 per 5% [95% CI: 1.02-1.47]; P = 0.03).ConclusionsAmong patients with CAD and ischemia, FMR severity and adverse mitral apparatus remodeling increase in proportion to contractile dysfunction underlying the mitral valve.     

3-Dimensional Strain Analysis of Hypertrophic Cardiomyopathy: Insights From the NHLBI International HCM Registry

BackgroundAbnormal global longitudinal strain (GLS) has been independently associated with adverse cardiac outcomes in both obstructive and nonobstructive hypertrophic cardiomyopathy.ObjectivesThe goal of this study was to understand predictors of abnormal GLS from baseline data from the National Heart, Lung, and Blood Institute (NHLBI) Hypertrophic Cardiomyopathy Registry (HCMR).MethodsThe study evaluated comprehensive 3-dimensional left ventricular myocardial strain from cine cardiac magnetic resonance in 2,311 patients from HCMR using in-house validated feature-tracking software. These data were correlated with other imaging markers, serum biomarkers, and demographic variables.ResultsAbnormal median GLS (> –11.0%) was associated with higher left ventricular (LV) mass index (93.8 ± 29.2 g/m² vs 75.1 ± 19.7 g/m²; P < 0.0001) and maximal wall thickness (21.7 ± 5.2 mm vs 19.3 ± 4.1 mm; P < 0.0001), lower left (62% ± 9% vs 66% ± 7%; P < 0.0001) and right (68% ± 11% vs 69% ± 10%; P < 0.01) ventricular ejection fractions, lower left atrial emptying functions (P < 0.0001 for all), and higher presence and myocardial extent of late gadolinium enhancement (6 SD and visual quantification; P < 0.0001 for both). Elastic net regression showed that adjusted predictors of GLS included female sex, Black race, history of syncope, presence of systolic anterior motion of the mitral valve, reverse curvature and apical morphologies, LV ejection fraction, LV mass index, and both presence/extent of late gadolinium enhancement and baseline N-terminal pro–B-type natriuretic peptide and troponin levels.ConclusionsAbnormal strain in hypertrophic cardiomyopathy is associated with other imaging and serum biomarkers of increased risk. Further follow-up of the HCMR cohort is needed to understand the independent relationship between LV strain and adverse cardiac outcomes in hypertrophic cardiomyopathy.     

Sex Differences in LV Remodeling and Hemodynamics in Aortic Stenosis: Sex-Specific Criteria for Severe Stenosis?

BackgroundThe current criteria for aortic stenosis (AS) severity have not incorporated sex-related differences.ObjectivesThe authors investigated sex-related serial changes in left ventricular (LV) structure/function and hemodynamics in AS.MethodsSerial echocardiograms of patients with severe AS (time 0; aortic valve area [AVA] ≤1 cm²) and ≥1 previous echocardiogram were compared between sexes.ResultsOf 927 patients (time 0: AVA 0.87 ± 0.11 cm², peak velocity 4.03 ± 0.65 m/s, mean Doppler systolic pressure gradient [MG] 40.6 ± 13.1 mm Hg), 393 (42%) were women. Women had smaller body surface area (BSA) (1.77 ± 0.22 m² vs 2.03 ± 0.20 m²; P < 0.001), lower stroke volume (SV) (81.1 ± 17.2 mL vs 88.3 ± 18.6 mL; P < 0.001), and more frequent low-gradient severe AS (n = 196 [50%] vs n = 181 [34%]; P < 0.001). Women consistently had smaller AVA, indexed AVA (AVAi), peak velocity, and MG than men. The difference in aortic valve gradient lessened when AVAi ≤0.6 cm²/m² was applied as severe AS (n = 694, women 43%, AVA 0.95 ± 0.17 cm², AVAi 0.50 ± 0.07 cm²/m²). Peak velocity (3.83 ± 0.66 m/s) and MG (36.5 ± 13.2 mm Hg) were lower based on AVAi severity criteria compared to those based on AVA. Men had a lower left ventricular ejection fraction (LVEF) (55.8% ± 14.8% vs 61.1% ± 11.7%; P < 0.001) and greater reduction in SV (?13.3 ± 19.6 mL vs ?7.4 ± 16.4 mL; P < 0.001) as AS progressed from moderate to severe. Concentric LV hypertrophy was more common and E/e? higher in women (21.2 ± 10.9 vs 18.8 ± 9.1; P < 0.001). SV, LVEF, AVA, peak velocity, and MG became precipitously worse when AVA reached 1.2 cm² in both sexes.ConclusionsSmaller BSA in women yields lower SV, resulting in lower aortic valve gradient than men. Indexed parameters by BSA are thus important in sex-related differences of aortic valve hemodynamics, but AVAi ≤0.6 cm²/m² includes individuals with moderate AS. Elevated filling pressure is more common in women. Men experience a larger reduction in SV and LVEF as AS progresses. The definition of AS severity may require different criteria between sexes.     

Clinical significance of heart rate variability for the monitoring of cardiac autonomic neuropathy in end-stage renal disease patients

Background and aimsThe aim of this study is to determine whether the measurement of continuous heart rate variability (HRV) is useful in the evaluation of cardiac autonomic neuropathy (CAN) in end-stage renal disease (ESRD) patients.Methods and resultsThis cross-sectional study was performed at Seoul St. Mary's hospital between June 2017 and February 2018. Seventy-seven ESRD patients, and 29 healthy controls (HCs) were asked to wear a continuous ambulatory HRV monitor for 24 h. General cardiac function was evaluated using transthoracic echocardiogram (TTE), pulse wave velocity (PWV), coronary calcium scoring (CCS), and 24-h ambulatory blood pressure monitoring (ABPM). HRV parameters of ESRD patients and HCs, and the correlation of HRV parameters with cardiovascular screening methods were observed. All HRV parameters were significantly decreased in ESRD patients compared to HCs (P < 0.001). In the correlation analysis between TTE results and HRV parameters, 24-h standard deviation of all N–N intervals (24SDNN), 24-h standard deviation of sequential 5-min N–N interval means (24DANN) and Low Frequency Power/High Frequency Power (LF/HF) ratio showed negative correlations with E/e’, LAVI and TR velocity which are representative indices for the diastolic function of the heart (P < 0.05). HRV parameters showed negative correlations with baPWV, CCS, and 24-h ABPM results as well (P < 0.05). Hemoglobin and serum albumin showed positive correlations with HRV parameters, and glucose, BUN, creatinine, and iPTH levels showed negative correlations (P < 0.05).ConclusionContinuous HRV monitoring may be a useful tool for the evaluation of CAN in ESRD.     

Association of Sex,Reduced Myocardial Flow Reserve,and Long-Term Mortality Across Spectrum of Atherosclerotic Disease

BackgroundCoronary vasomotor dysfunction (defined by reduced myocardial blood flow reserve [MBFR]) is associated with high cardiac risk in both men and women in absence of significant coexisting epicardial disease. Whether there is a sex-specific difference in prognostic value of reduced MBFR in patients with a greater burden of coexisting epicardial atherosclerotic disease is not well understood.ObjectivesThe purpose of this study was to examine the association of sex, MBFR, and mortality in consecutive patients with suspected or known coronary artery disease undergoing positron emission tomography myocardial perfusion imaging.MethodsUnique consecutive patients undergoing rubidium (Rb)-82 rest/stress positron emission tomography myocardial perfusion imaging from 2010-2016 were followed for a median of 3.2 years. Multivariable Cox models were built to describe the interaction of sex and MBFR on all-cause and cardiac death for the overall population and stratified by extent of calcified atherosclerosis (none: coronary artery calcium score = 0, subclinical: coronary artery calcium >0, clinical: prior myocardial infarction/percutaneous coronary intervention) and abnormal perfusion (no significant obstructive disease: summed stress score = 0, 1%-9.9%, and ≥10%) at baseline.ResultsAmong 12,594 patients, 52.8% were women. Compared with men, women had a lower prevalence of known coronary artery disease (16.5% vs 29.5%; P < 0.001) and were less likely to undergo revascularization after myocardial perfusion imaging (4.9% vs 9.7%; P < 0.001), but were more likely to have a reduced MBFR of <2 (56.2% vs 50.6%; P < 0.001). There were 1,699 (13.5%) all-cause and 490 (3.9%) cardiac deaths. In fully adjusted Cox models, reduced MBFR was independently associated with higher risk of death (HR per 0.1-U decrease: 1.09 [95% CI: 1.08-1.10]; P < 0.001), but female sex was not (HR: 0.95 [95% CI: 0.85-1.05]; P = 0.27). There was no significant interaction between sex and MBFR on death (P = 0.22) and cardiac death (P = 0.35) overall or in subgroups of patients with clinical, subclinical, and no atherosclerosis or across categories of perfusion abnormality at baseline.ConclusionsThe association between reduced MBFR and higher risk of all-cause and cardiac death did not differ by sex, regardless of extent of coexisting atherosclerosis or perfusion abnormality.     

1-Year Outcomes of Cardioband Tricuspid Valve Reconstruction System Early Feasibility Study

BackgroundTricuspid regurgitation (TR) is prevalent and undertreated, with mortality and morbidity increasing with TR severity. Given poor outcomes with medical therapy and high in-hospital mortality for isolated tricuspid valve surgery, emerging transcatheter repair devices offer a promising alternative.ObjectivesThe Edwards Cardioband Tricuspid Valve Reconstruction System Early Feasibility study (NCT03382457) evaluates the treatment of functional TR via annular reduction with the Cardioband Tricuspid Valve Reconstruction System (Edwards Lifesciences).MethodsPatients with ≥ moderate functional TR were eligible for this prospective, single-arm multicenter study. At 1 year, patients were evaluated for echocardiographic parameters, clinical and quality-of-life measures, and major adverse events.ResultsThe 37 patients enrolled had a mean age of 78 years; 76% were female; and they had ≥ severe functional (97.3%) or mixed (2.7%) TR, atrial flutter/fibrillation (97%), and New York Heart Association functional class III/IV (65%). At 1 year, 73.0% achieved ≤ moderate TR (P < 0.0001), and 73.1% had ≥2 grade reductions. Echocardiography showed significant reductions in the tricuspid annulus diameter (P < 0.0001), mean vena contracta (P < 0.0001), proximal isovelocity surface area effective regurgitant orifice area (P < 0.0001), right ventricular end-diastolic diameter (P < 0.0001), and inferior vena contracta (P = 0.0006). New York Heart Association functional class improved significantly (P < 0.0001), with 92.3% achieving class I/II, and Kansas City Cardiomyopathy Questionnaire scores improved by 19.0 points (P < 0.0001). One-year cardiovascular mortality was 8.1%, reinterventions were necessary in 5.4%, major access site complications occurred in 8.1%, and severe bleeding was noted in 35.1% of patients. Kaplan-Meier estimates of survival and freedom from heart failure rehospitalization were 85.9% and 88.7%, respectively.ConclusionsOne-year experience using the Cardioband system for tricuspid valve repair shows high survival and low rehospitalization rates with durable outcomes in TR reduction and echocardiographic, clinical, and quality-of-life outcomes.     

Cardiac Magnetic Resonance Assessment of Response to Cardiac Resynchronization Therapy and Programming Strategies

ObjectivesThe objective was to determine the feasibility and effectiveness of cardiac magnetic resonance (CMR) cine and strain imaging before and after cardiac resynchronization therapy (CRT) for assessment of response and the optimal resynchronization pacing strategy.BackgroundCMR with cardiac implantable electronic devices can safely provide high-quality right ventricular/left ventricular (LV) ejection fraction (RVEF/LVEF) assessments and strain.MethodsCMR with cine imaging, displacement encoding with stimulated echoes for the circumferential uniformity ratio estimate with singular value decomposition (CURE-SVD) dyssynchrony parameter, and scar assessment was performed before and after CRT. Whereas the pre-CRT scan constituted a single “imaging set” with complete volumetric, strain, and scar imaging, multiple imaging sets with complete strain and volumetric data were obtained during the post-CRT scan for biventricular pacing (BIVP), LV pacing (LVP), and asynchronous atrial pacing modes by reprogramming the device outside the scanner between imaging sets.Results100 CMRs with a total of 162 imaging sets were performed in 50 patients (median age 70 years [IQR: 50-86 years]; 48% female). Reduction in LV end-diastolic volumes (P = 0.002) independent of CRT pacing were more prominent than corresponding reductions in right ventricular end-diastolic volumes (P = 0.16). A clear dependence of the optimal CRT pacing mode (BIVP vs LVP) on the PR interval (P = 0.0006) was demonstrated. The LVEF and RVEF improved more with BIVP than LVP with PR intervals ≥240 milliseconds (P = 0.025 and P = 0.002, respectively); the optimal mode (BIVP vs LVP) was variable with PR intervals <240 milliseconds. A lower pre-CRT displacement encoding with stimulated echoes (DENSE) CURE-SVD was associated with greater improvements in the post-CRT CURE-SVD (r = −0.69; P < 0.001), LV end-systolic volume (r = −0.58; P < 0.001), and LVEF (r = −0.52; P < 0.001).ConclusionsCMR evaluation with assessment of multiple pacing modes during a single scan after CRT is feasible and provides useful information for patient care with respect to response and the optimal pacing strategy.     

Transfemoral Tricuspid Valve Replacement in Patients With Tricuspid Regurgitation: TRISCEND Study 30-Day Results

ObjectivesThe TRISCEND study (Edwards EVOQUE Tricuspid Valve Replacement: Investigation of Safety and Clinical Efficacy after Replacement of Tricuspid Valve with Transcatheter Device) is evaluating the safety and performance of transfemoral transcatheter tricuspid valve replacement in patients with clinically significant tricuspid regurgitation (TR) and elevated surgical risk.BackgroundTranscatheter valve replacement could lead to a paradigm shift in treating TR and improving patient quality of life.MethodsIn the prospective, single-arm, multicenter TRISCEND study, patients with symptomatic moderate or greater TR, despite medical therapy, underwent percutaneous transcatheter tricuspid valve replacement with the EVOQUE system. A composite rate of major adverse events, echocardiographic parameters, and clinical, functional, and quality-of-life measures were assessed at 30 days.ResultsFifty-six patients (mean age of 79.3 years, 76.8% female, 91.1% TR severe or greater, 91.1% atrial fibrillation, and 87.5% New York Heart Association functional class III or IV) were treated. At 30 days, TR was reduced to mild or less in 98%. The composite major adverse events rate was 26.8% at 30 days caused by 1 cardiovascular death in a patient with a failed procedure, 2 reinterventions after device embolization, 1 major access site or vascular complication, and 15 severe bleeds, of which none were life-threatening or fatal. No myocardial infarction, stroke, renal failure, major cardiac structural complications, or device-related pulmonary embolism were observed. New York Heart Association significantly improved to functional class I or II (78.8%; P < 0.001), 6-minute walk distance improved 49.8 m (P < 0.001), and Kansas City Cardiomyopathy Questionnaire score improved 19 points (P < 0.001).ConclusionsEarly experience with the transfemoral EVOQUE system in patients with clinically significant TR demonstrated technical feasibility, acceptable safety, TR reduction, and symptomatic improvement at 30 days. The TRISCEND II randomized trial (NCT04482062) is underway.     

Structural Cardiac Remodeling in Atrial Fibrillation

ObjectivesThis study sought to evaluate preablation computed tomography angiography (CTA) for atrial and epicardial features to predict atrial fibrillation (AF) recurrence after ablation.BackgroundStructural atrial remodeling is a process associated with occurrence or persistence of AF. Different anatomical imaging features have been proposed to influence atrial remodeling both negatively and positively as substrate for AF.MethodsPatients with nonvalvular AF underwent cardiac CTA before pulmonary vein isolation at 2 high-volume centers. Left atrial (LA) and right atrial volumes, LA wall thickness (LAWT), and epicardial adipose tissue volume and attenuation were evaluated. Additional subanalyses of electroanatomical maps were made. Follow-up was performed for at least 12 months, including subanalysis of repeated cardiac CTA studies. Interrater variability was assessed.ResultsOf 732 patients, 270 (36.9%) had AF recurrence after a mean of 7 months. CT analysis revealed larger indexed LA volume (47.3 mL/m² vs 43.6 mL/m²; P = 0.0001) and higher mean anterior (1.91 mm vs 1.65 mm; P < 0.0001) and posterior (1.61 mm vs 1.39 mm; P = 0.001) LAWT in patients with AF recurrence. Epicardial adipose tissue volume in patients with AF recurrence was higher (144.5 mm³ vs 128.5 mm³; P < 0.0001) and further progressed significantly in a subset of 85 patients after 2 years (+11.8 mm² vs −3.5 mm²; P = 0.041). Attenuation levels were lower, indicating a higher lipid component associated with AF recurrence (−69.1 HU vs −67.5 HU; P = 0.001). A total of 103 atrial voltage maps were highly predictive of AF recurrence and showed good discriminatory power for patients with low voltage >50% and LAWT (1.55 ± 0.5 mm vs 1.81 ± 0.6 mm; P = 0.032). Net reclassification improvement (NRI) showed a significant incremental benefit (NRI = 0.279; P < 0.0001) when adding LAWT to established risk models.ConclusionsAtrial wall thickness, epicardial fat volume, and attenuation are associated with AF recurrence in patients undergoing ablation therapy.     

Entropy as a Measure of Myocardial Tissue Heterogeneity in Patients With Ventricular Arrhythmias

ObjectivesThe authors investigated the incremental prognostic value of entropy, a novel measure of myocardial tissue heterogeneity by cardiac magnetic resonance (CMR) imaging in patients presenting with ventricular arrhythmias (VAs).BackgroundCMR can characterize myocardial areas serving as arrhythmogenic substrate.MethodsConsecutive patients undergoing CMR imaging for VAs were followed for major adverse cardiac events (MACEs) defined by all-cause death, incident VAs requiring therapy, or heart failure hospitalization. Entropy was derived from the probability distribution of pixel signal intensities of the left ventricular (LV) myocardium.ResultsA total of 583 patients (age 54 ± 15 years, female 39%, left ventricular ejection fraction [LVEF] 54 ± 13%) were followed for a median of 4.4 years and experienced 141 MACEs. Entropy showed strong unadjusted association with MACE (HR: 1.88; 95% CI: 1.63-2.17; P < 0.001). In a multivariable model including LVEF, QRS duration, late gadolinium enhancement, and presenting arrhythmia, entropy maintained independent association with MACE (HR: 1.61; 95% CI: 1.32-1.96; P < 0.001). Entropy was further significantly associated with MACE in patients without myocardial scar (HR: 2.43; 95% CI: 1.55-3.82; P < 0.001) and in those presenting with nonsustained VAs (HR: 2.16; 95% CI: 1.43-3.25; P < 0.001). Addition of LV entropy to the baseline multivariable model significantly improved model performance (C-statistic improvement: 0.725 to 0.754; P = 0.003) and risk reclassification.ConclusionsIn patients with VAs, CMR-assessed LV entropy was independently associated with MACE and provided incremental prognostic value, on top of LVEF and late gadolinium enhancement. LV entropy assessment may help risk stratification in patients with absence of myocardial scar or with nonsustained VAs.     

Relationship Between Coronary Artery Calcium and Atherosclerosis Progression Among Patients With Suspected Coronary Artery Disease

BackgroundAmong symptomatic patients, it remains unclear whether a coronary artery calcium (CAC) score alone is sufficient or misses a sizeable burden and progressive risk associated with obstructive and nonobstructive atherosclerotic plaque.ObjectivesAmong patients with low to high CAC scores, our aims were to quantify co-occurring obstructive and nonobstructive noncalcified plaque and serial progression of atherosclerotic plaque volume.MethodsA total of 698 symptomatic patients with suspected coronary artery disease (CAD) underwent serial coronary computed tomographic angiography (CTA) performed 3.5 to 4.0 years apart. Atherosclerotic plaque was quantified, including by compositional subgroups. Obstructive CAD was defined as ≥50% stenosis. Multivariate linear regression models were used to measure atherosclerotic plaque progression by CAC scores. Cox proportional hazard models estimated CAD event risk (median of 10.7 years of follow-up).ResultsAcross baseline CAC scores from 0 to ≥400, total plaque volume ranged from 30.4 to 522.4 mm³ (P < 0.001) and the prevalence of obstructive CAD increased from 1.4% to 49.1% (P < 0.001). Of those with a 0 CAC score, 97.9% of total plaque was noncalcified. Among patients with baseline CAC <100, nonobstructive CAD was prevalent (40% and 89% in CAC scores of 0 and 1-99), with plaque largely being noncalcified. On the follow-up coronary CTA, volumetric plaque growth (P < 0.001) and the development of new or worsening stenosis (P < 0.001) occurred more among patients with baseline CAC ≥100. Progression varied compositionally by baseline CAC scores. Patients with no CAC had disproportionate growth in noncalcified plaque, and for every 1 mm³ increase in calcified plaque, there was a 5.5 mm³ increase in noncalcified plaque volume. By comparison, patients with CAC scores of ≥400 exhibited disproportionate growth in calcified plaque with a volumetric increase 15.7-fold that of noncalcified plaque. There was a graded increase in CAD event risk by the CAC with rates from 3.3% for no CAC to 21.9% for CAC ≥400 (P < 0.001).ConclusionsCAC imperfectly characterizes atherosclerotic disease burden, but its subgroups exhibit pathogenic patterns of early to advanced disease progression and stratify long-term prognostic risk.     

Coronary Flow Assessment Using 3-Dimensional Ultrafast Ultrasound Localization Microscopy

BackgroundDirect assessment of the coronary microcirculation has long been hampered by the limited spatial and temporal resolutions of cardiac imaging modalities.ObjectivesThe purpose of this study was to demonstrate 3-dimensional (3D) coronary ultrasound localization microscopy (CorULM) of the whole heart beyond the acoustic diffraction limit (<20 μm resolution) at ultrafast frame rate (>1000 images/s).MethodsCorULM was performed in isolated beating rat hearts (N = 6) with ultrasound contrast agents (Sonovue, Bracco), using an ultrasonic matrix transducer connected to a high channel–count ultrafast electronics. We assessed the 3D coronary microvascular anatomy, flow velocity, and flow rate of beating hearts under normal conditions, during vasodilator adenosine infusion, and during coronary occlusion. The coronary vasculature was compared with micro-computed tomography performed on the fixed heart. In vivo transthoracic CorULM was eventually assessed on anaesthetized rats (N = 3).ResultsCorULM enables the 3D visualization of the coronary vasculature in beating hearts at a scale down to microvascular structures (<20 μm resolution). Absolute flow velocity estimates range from 10 mm/s in tiny arterioles up to more than 300 mm/s in large arteries. Fitting to a power law, the flow rate–radius relationship provides an exponent of 2.61 (r² = 0.96; P < 0.001), which is consistent with theoretical predictions and experimental validations of scaling laws in vascular trees. A 2-fold increase of the microvascular coronary flow rate is found in response to adenosine, which is in good agreement with the overall perfusion flow rate measured in the aorta (control measurement) that increased from 8.80 ± 1.03 mL/min to 16.54 ± 2.35 mL/min (P < 0.001). The feasibility of CorULM was demonstrated in vivo for N = 3 rats.ConclusionsCorULM provides unprecedented insights into the anatomy and function of coronary arteries at the microvasculature level in beating hearts. This new technology is highly translational and has the potential to become a major tool for the clinical investigation of the coronary microcirculation.