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Using a contemporary, multicenter international single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) registry, this study characterized the potential major adverse cardiovascular event(s) (MACE) benefit of early revascularization based on automatic quantification of ischemia. Prior single-center data reported an association between moderate to severe ischemia SPECT-MPI and reduced cardiac death with early revascularization. Consecutive patients from a multicenter, international registry who underwent 99mTc SPECT-MPI between 2009 and 2014 with solid-state scanners were included. Ischemia was quantified automatically as ischemic total perfusion deficit (TPD). Early revascularization was defined as within 90 days. The primary outcome was MACE (death, myocardial infarction, and unstable angina). A propensity score was developed to adjust for nonrandomization of revascularization; then, multivariable Cox modeling adjusted for propensity score and demographics was used to predict MACE. In total, 19,088 patients were included, with a mean follow-up of 4.7 ± 1.6 years, during which MACE occurred in 1,836 (9.6%) patients. There was a significant interaction between ischemic TPD modeled as a continuous variable and early revascularization (interaction p value: 0.012). In this model, there was a trend toward reduced MACE in patients with >5.4% ischemic TPD and a significant association with reduced MACE in patients with >10.2% ischemic TPD. In this large, international, multicenter study reflecting contemporary cardiology practice, early revascularization of patients with >10.2% ischemia on SPECT-MPI, quantified automatically, was associated with reduced MACE. [ABSTRACT FROM AUTHOR]

Background: Severity of left atrial (LA) fibrosis is a strong predictor of atrial fibrillation (AF) ablation success and has been associated with a history of stroke, hypertension, and heart failure (HF). However, it is unclear whether more severe LA fibrosis independently increases the risk of major adverse cardiovascular and cerebrovascular events (MACCE) among those with AF.Objectives: The goal of this study was to evaluate the occurrence and frequency of MACCE by strata of LA fibrosis severity in patients with AF.Methods: This was a retrospective cohort study of 1,228 patients with AF who underwent late gadolinium enhancement (LGE)-cardiac magnetic resonance imaging to quantify LA fibrosis severity between January 2007 and June 2015. Patients were stratified according to Utah stage of LA LGE criteria, and observed for the occurrence of MACCE, which included a composite of stroke or transient ischemic attack (TIA), myocardial infarction, acute decompensated HF, or cardiovascular death. Disease risk score (DRS) stratification was used to control for between-group differences in baseline characteristics and risk.Results: During follow-up, 62 strokes or TIAs, 42 myocardial infarctions, 156 HF events, and 38 cardiovascular deaths occurred. In DRS stratified analysis, the hazard ratio comparing patients with stage IV versus stage I LA LGE was 1.67 (95% confidence interval: 1.01 to 2.76) for the composite MACCE outcome. The only individual component of the MACCE outcome to remain significantly associated with advanced LGE following DRS stratification was stroke or TIA (hazard ratio: 3.94; 95% confidence interval: 1.72 to 8.98).Conclusions: This retrospective analysis demonstrated that more severe LA LGE is associated with increased MACCE risk, driven primarily by increased risk of stroke or TIA. [ABSTRACT FROM AUTHOR]

Background Leaflet thrombosis after valve-in-valve (ViV) procedure has been increasingly recognized. This study aimed to investigate the flow dynamics aspect of leaflet thrombosis by quantifying the blood stasis on the noncoronary and coronary leaflets of a surgical aortic valve (SAV) and a transcatheter aortic valve (TAV) in a ViV setting. Methods Two computational models, representing a SAV and a TAV in ViV setting, were developed in a patient-specific geometry. Three-dimensional flow fields were obtained through a fluid-solid interaction modeling approach to study the difference in blood residence time (BRT) on the coronary and noncoronary leaflets. Results Longer BRT was observed on the TAV leaflets compared with the SAV, specifically near the leaflet fixed boundary. Particularly, at the end of diastole, the areas of high BRT (≥1.2 seconds) on the surface of the TAV model leaflets were four times larger than those of the SAV model. The distribution of BRT on the three leaflets exhibited a similar pattern in the model for the TAV in ViV setting. That was in contrast to the SAV model where large areas of high BRT were observed on the noncoronary leaflet. Conclusions Geometric confinement of the TAV by the leaflets and the frame of the degenerated bioprosthesis that circumferentially surround the TAV stent increases the BRT on the leaflets, which may act as a permissive factor in the TAV leaflet thrombosis after ViV procedure. A similar distribution pattern of BRT observed on the TAV leaflets may explain the similar rate of occurrence of thrombosis on the three leaflets. [ABSTRACT FROM AUTHOR]

Background: The “July phenomenon” describes poor patient outcomes in teaching hospitals at the beginning of a new academic year when trainees begin. Whether this phenomenon truly exists is unclear. Objective: The purpose of this study was to identify whether trainee and attending inexperience is associated with cardiac electrophysiologic procedural outcomes including total procedure time, fluoroscopy time, and complications. Methods: We retrospectively reviewed the available electronic records of 488 consecutive patients undergoing initial dual-chamber pacemaker (PM) or cardiac resynchronization therapy (CRT) device implantation performed at University of California, San Francisco from February 2004 through November 2011. We calculated physician’s year of experience using the procedure date and the physician’s job start date. Patients were stratified into two subgroups based on their device type. Procedural outcomes including procedure length, fluoroscopy time, and complications were retrieved from electronic databases. Results: After multivariate analysis, fellow experience was associated with decreased procedure time (19% less procedure time/year of experience, 95% confidence interval [CI] 13%–25%, P <.001 in the PM subgroup; and 15% less procedure time/year of experience, 95% CI 7%–23%, P <.001 in the CRT subgroup). Fellow experience was associated with decreased fluoroscopy time in the CRT subgroup (19% less fluoroscopy time/experience years, 95% CI 5%–34%, P = .009). Neither fellow nor attending experience was associated with complications. Conclusion: Each year of fellow experience is associated with a decrease in cardiac device implantation procedure time and a decrease in fluoroscopy time during CRT implantation. No associations between fellow experience and in-hospital complications were observed. [Copyright &y& Elsevier]

Objectives: This study compared the ability of automated myocardial perfusion imaging analysis to predict major adverse cardiac events (MACE) to that of visual analysis., Background: Quantitative analysis has not been compared with clinical visual analysis in prognostic studies., Methods: A total of 19,495 patients from the multicenter REFINE SPECT (REgistry of Fast Myocardial Perfusion Imaging with NExt generation SPECT) study (64 ± 12 years of age, 56% males) undergoing stress Tc-99m-labeled single-photon emission computed tomography (SPECT) myocardial perfusion imaging were followed for 4.5 ± 1.7 years for MACE. Perfusion abnormalities were assessed visually and categorized as normal, probably normal, equivocal, or abnormal. Stress total perfusion deficit (TPD), quantified automatically, was categorized as TPD = 0%, TPD >0% to <1%, ≤1% to <3%, ≤3% to <5%, ≤5% to ≤10%, or TPD >10%. MACE consisted of death, nonfatal myocardial infarction, unstable angina, or late revascularization (>90 days). Kaplan-Meier and Cox proportional hazards analyses were performed to test the performance of visual and quantitative assessments in predicting MACE., Results: During follow-up examinations, 2,760 (14.2%) MACE occurred. MACE rates increased with worsening of visual assessments, that is, the rate for normal MACE was 2.0%, 3.2% for probably normal, 4.2% for equivocal, and 7.4% for abnormal (all p < 0.001). MACE rates increased with increasing stress TPD from 1.3% for the TPD category of 0% to 7.8% for the TPD category of >10% (p < 0.0001). The adjusted hazard ratio (HR) for MACE increased even in equivocal assessment (HR: 1.56; 95% confidence interval [CI]: 1.37 to 1.78) and in the TPD category of ≤3% to <5% (HR: 1.74; 95% CI: 1.41 to 2.14; all p < 0.001). The rate of MACE in patients visually assessed as normal still increased from 1.3% (TPD = 0%) to 3.4% (TPD ≥5%) (p < 0.0001)., Conclusions: Quantitative analysis allows precise granular risk stratification in comparison to visual reading, even for cases with normal clinical reading., (Copyright © 2020 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: There is an increasing awareness of leaflet thrombosis following transcatheter aortic valve implantation (TAVI) and valve-in-valve (ViV) procedures. Nevertheless, the predisposing factors affecting transcatheter aortic valve (TAV) thrombosis have remained unclear. This study aimed to quantify the effects of reduced cardiac output (CO) on blood stasis on the TAV leaflets as a permissive factor for valve thrombosis., Methods and Results: An idealised computational model representing a TAV was developed in a patient-specific geometry. Three-dimensional flow fields were obtained via a fluid-solid interaction modelling approach at different COs: 5.0, 3.5, 2.0 L/min. Blood residence time (BRT) was subsequently calculated on the leaflets. An association between reduced CO and increased blood stasis on the TAV leaflets was observed. At the end of diastole, larger areas of high BRT (>1.2 s) were observed at the leaflet's fixed edge at low COs. Such areas were calculated to be 2, 8, and 11% of the total surface area of leaflets at CO=5.0, 3.5, and 2.0 L/min, respectively, indicating a ~sixfold increase of BRT on the leaflets from the highest to the lowest CO., Conclusions: This study indicates an association between reduced CO and increased blood stasis on the TAV leaflets which can be regarded as a precursor of valve thrombosis.

Objectives: Leaflet thrombosis following transcatheter aortic valve replacement (TAVR) and valve-in-valve (ViV) procedures has been increasingly recognized. However, the factors affecting the post-TAVR/ViV thrombosis are not fully understood. This study aimed to investigate the effect of the geometric confinement of transcatheter aortic valve (TAV) on blood residence time (BRT) on the TAV leaflets and in turn on the post-TAVR valve thrombosis., Methods: Two computational models, representing a surgical bioprosthesis and a TAV, were developed to study the effect of the geometric confinement on BRT on the leaflets in ViV setting/TAVR Intra-annular positioning. 3D flow fields were obtained via a one-way fluid-solid interaction modelling approach validated by experimental testing. BRT was compared between the two models by quantification and statistical analysis of the residence time of randomly distributed particles in close proximity of the leaflets., Results: Significantly longer BRT on the leaflets was observed in the TAV compared to the surgical valve during different stages of the cardiac cycle. During forward flow, the mean value of BRT was found to be 39% higher in the TAV compared to the surgical bioprosthesis ( P <  0.0001). During diastole, specifically from end-systole to mid-diastole and from mid-diastole to the beginning of systole, the amount by which the mean BRT was higher for TAV compared to the surgical valve was 150% and 40%, respectively ( P <  0.0005)., Conclusions: The geometric confinement of TAV by the failed bioprosthesis or the calcified native valve increases the BRT on the TAV leaflets. This may act as a permissive factor in valve thrombosis., (© The Author 2017. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: Left bundle branch block (LBBB) has been proposed as a risk factor for cardiovascular morbidity and mortality. We sought to characterize the strength of these associations in a population without preexisting clinical heart disease., Methods: The association between LBBB and new-onset congestive heart failure (CHF) or death from cardiovascular diseases was examined in 1,688 participants enrolled in the SPPARCS study who were free of known CHF or previous myocardial infarction. SPPARCS is a community-based cohort study in residents of Sonoma, California that are > 55 years. Medical history and 12-lead ECGs were obtained every 2 years for up to 6 years of follow-up. LBBB at enrollment or year 2 was considered "baseline" and assessed as a predictor of CHF and cardiovascular death ascertained at years 4 and 6., Results: The prevalence of LBBB at baseline was 2.5% (n = 42). During 6 years of follow-up, 70 (4.8%) people developed new CHF. Incidence of CHF was higher in patients with LBBB than in participants without LBBB. This association persisted after controlling for potential confounders (odds ratio (OR): 2.85; 95% confidence interval (CI): 1.01 - 8.02; P = 0.047). A higher mortality from cardiovascular diseases was also found in participants with LBBB after adjusting for potential confounders (OR: 2.35, 95%CI: 1.02 - 5.41; P = 0.044)., Conclusions: LBBB in the absence of a clinically detectable heart disease is associated with new-onset CHF and death from cardiovascular diseases. Further study is warranted to determine if additional diagnostic testing or earlier treatment in patients with asymptomatic LBBB can decrease cardiovascular morbidity or mortality.