Aims: Conventional fractional flow reserve (FFR) is measured invasively using a coronary guidewire equipped with a pressure sensor. A non-invasive derived FFR would eliminate risk of coronary injury, minimize technical limitations, and potentially increase adoption. We aimed to evaluate the diagnostic performance of a computational pressure-flow dynamics derived FFR (caFFR), applied to coronary angiography, compared to invasive FFR.Methods and results: The FLASH FFR study was a prospective, multicentre, single-arm study conducted at six centres in China. Eligible patients had native coronary artery target lesions with visually estimated diameter stenosis of 30–90% and diagnosis of stable or unstable angina pectoris. Using computational pressure-fluid dynamics, in conjunction with thrombolysis in myocardial infarction (TIMI) frame count, applied to coronary angiography, caFFR was measured online in real-time and compared blind to conventional invasive FFR by an independent core laboratory. The primary endpoint was the agreement between caFFR and FFR, with a pre-specified performance goal of 84%. Between June and December 2018, matched caFFR and FFR measurements were performed in 328 coronary arteries. Total operational time for caFFR was 4.54 ± 1.48 min. caFFR was highly correlated to FFR (R = 0.89, P = 0.76) with a mean bias of −0.002 ± 0.049 (95% limits of agreement −0.098 to 0.093). The diagnostic performance of caFFR vs. FFR was diagnostic accuracy 95.7%, sensitivity 90.4%, specificity 98.6%, positive predictive value 97.2%, negative predictive value 95.0%, and area under the receiver operating characteristic curve of 0.979.Conclusions: Using wire-based FFR as the reference, caFFR has high accuracy, sensitivity, and specificity. caFFR could eliminate the need of a pressure wire, technical error and potentially increase adoption of physiological assessment of coronary artery stenosis severity.Clinical Trial Registration: URL: http://www.chictr.org.cn Unique Identifier: ChiCTR1800019522.

Background: The adherence to secondary prevention treatment in patients with coronary heart disease (CHD) is low. Digital therapeutics (DTx) refers to an emerging branch of medicine that delivers medical interventions directly to patients using evidence-based, clinically evaluated, technology-based software algorithms or apps to facilitate disease management, which may be an efficient tool to optimize adherence. Objective: This paper aims to investigate the effect of mobile app–based self-management DTx on long-term use of secondary prevention medications in patients with CHD in China. Methods: This pilot study was a parallel-designed, open-labeled, single-center, randomized controlled trial. Hospitalized patients with CHD admitted to Peking University First Hospital between April 2016 and June 2017 were randomized before discharge on a 1:1 ratio. The intervention group received regular follow-up combined with DTx, which is a self-management mobile app already installed on an Android 5 (Mi Pad 1, Xiaomi Corporation) tablet. Structured data from the hospital informatics system were integrated automatically, and medication, lifestyle intervention plan, follow-up protocol, and patient education materials were also provided according to the diagnosis. Participants could use DTx for self-management at home. The control group was under conventional hospital–based follow-up care. Patients were followed up for 1 year, and the primary end point was the percentage of all guideline-recommended medications at 12 months. The secondary end points included the percentage adhered to standard secondary prevention medications at 6 months, the control rate of lipid profile, and blood pressure at 6 months and 1 year. Results: Among 300 randomized patients with CHD, 290 (96.7%) were included in the final analysis, including 49.3% (143/290) and 50.7% (147/290) of patients from the intervention and control groups, respectively. Baseline characteristics were similar between the 2 groups. There was a statistically significant improvement in the percentage of all guideline-recommended medications at 12 months in the intervention group compared with the control group (relative risk [RR] 1.34, 95% CI 1.12-1.61; P=.001), and there was no interaction with baseline characteristics. The intervention group had a significantly higher proportion of patients achieving blood pressure under control (systolic blood pressure <140 mm Hg and diastolic blood pressure <90 mm Hg) and low-density lipoprotein cholesterol <1.8 mmol/L (RR 1.45, 95% CI 1.22-1.72; P<.001 and RR 1.40, 95% CI 1.11-1.75; P=.004, respectively) at 12 months. Furthermore, on logistic regression, the intervention group had a lower risk of withdrawing from guideline-recommended medications (odds ratio 0.46, 95% CI 0.27-0.78; P=.004). Conclusions: Among patients with CHD, using a mobile app–based self-management DTx in addition to traditional care resulted in a significant improvement in guideline-recommended medication adherence at 12 months. The results of the trial will be applicable to primary care centers, especially in rural areas with less medical resources. Trial Registration: ClinicalTrials.gov NCT03565978; https://clinicaltrials.gov/ct2/show/NCT03565978

Cardiovascular disease remains the leading cause of morbidity and mortality worldwide, with ischemic heart disease being a major contributor, either through coronary atherosclerotic plaque-related major vascular disease or coronary microvascular dysfunction. Obstruction of coronary blood flow impairs myocardial perfusion, which may lead to acute myocardial infarction in severe cases. The subendocardial viability ratio, also known as the Buckberg index, is a valuable tool for evaluation of myocardial perfusion because it reflects the balance between myocardial oxygen supply and oxygen demand. The subendocardial viability ratio can effectively evaluate the function of the coronary microcirculation and is associated with arterial stiffness. This ratio also has potential value in predicting adverse cardiovascular events and mortality in various populations. Moreover, the subendocardial viability ratio has demonstrated clinical significance in a range of diseases, including hypertension, aortic stenosis, peripheral arterial disease, chronic kidney disease, diabetes, and rheumatoid arthritis. This review summarizes the applications of the subendocardial viability ratio, its particular progress in the relevant research, and its clinical significance in cardiovascular diseases.

Objectives: To evaluate the optimal revascularization strategy for patients with coronary artery disease (CAD) and end stage renal disease (ESRD) in the drug-eluting stent (DES) era. Methods: One hundred and twelve patients with ESRD treated with coronary artery bypass grafting (CABG) or percutaneous coronary intervention (PCI) were enrolled from 2007 to 2017. All patients were dialysis-dependent, of which 26 received CABG and 86 underwent PCI. The primary endpoint was all-cause mortality. Secondary endpoints were major adverse cardiovascular events including myocardial infarction, stroke, repeat revascularization, and death. Results: The CABG group had a higher prevalence of left main CAD (57.7% vs. 11.6%, p < .01) compared with PCI group. The short-term (within 30 days after the procedure) risk of death was higher in CABG group compared with PCI group (15.4% vs. 1.2%, p < .05). The two groups exhibited similar rate of primary endpoints (50.0% vs. 40.7%, p = .37) and secondary endpoints (65.4% vs. 60.5%, p = .97) in long-term observation. Multivariate Cox regression showed that patients older than 65 or underwent peritoneal dialysis (PD) had significant higher rate of mortality than those under 65 (HR 2.85; 95% CI 1.20–6.85; p < .05) or underwent hemodialysis (HD) (HR 6.69; 95% CI 2.35–19.05; p < .01). Conclusions: Among patients with CAD and dialysis-dependent chronic kidney disease (CKD), treatment with CABG or PCI with DES exhibited similar long-term outcomes. However, CABG was associated with higher short-term risk of death. Higher mortality was revealed in patients over 65 years and underwent PD.

Objectives: The aim of this study was to investigate the potential prognostic value of post-percutaneous coronary intervention (PCI) angiography-derived fractional flow reserve (FFR) and its gradient across the stent.Background: Post-PCI FFR and its gradient across the stent have been proved to be associated with clinical outcomes. However, little is known about the prognostic value of post-PCI coronary angiography-derived FFR and its gradient across the stent.Methods: Patients diagnosed with coronary heart disease and participated in drug-eluting stent (DES) clinical trials for stent implantation in a single center were included for this retrospective analysis. A novel coronary angiography-derived FFR (caFFR) and its gradient across the stent were calculated offline using two projections from coronary angiography performed after PCI. Clinical follow-up was completed at 9 months after the index procedure and the primary outcome was target vessel failure (TVF), defined as a composite of target vessel-related myocardial infarction (MI), target vessel-related revascularization (TVR), and cardiac death. Coronary angiography was also performed at the 9 months follow-up time to get data of late lumen loss (LLL) and percent diameter stenosis (%DS).Results: A total of 159 vessels in 136 patients were analyzed. The mean value of post-PCI caFFR was 0.90 ± 0.06. The median value of trans-stent caFFR gradient (ΔcaFFR_stent) was 0.04 (interquartile range 0.02–0.08). ΔcaFFR_stent>0 was demonstrated in 147 vessels (92.45%). The TVF rate was significantly higher in patients with post-PCI caFFR < 0.90 (4 [8.16%] vs. 1 [1.15%], P = 0.037), which was mainly achieved by the difference between the TVR rate. In the subgroup with lesions located in the left anterior descending coronary artery (LAD), post-PCI caFFR was an independent predictor of LLL (β = −1.07, 95% CI: −1.74 to −0.39, P = 0.002) and %DS at follow-up (β = −30.24, 95% CI: −56.44 to −4.04, P = 0.025), ΔcaFFR_stent was an independent predictor of LLL (β=0.98, 95% CI:0.13–1.83, P = 0.026).Conclusion: Suboptimal post-PCI caFFR and trans-stent caFFR gradient were common among vessels immediately after stenting. Lower post-PCI caFFR was associated with a higher rate of 9-month TVF. After LAD PCI, both post-PCI caFFR and its gradient across stent were independent predictors of the neointimal proliferation of the target vessel evaluated by LLL and %DS at follow-up.

Background: Cardiac amyloidosis (CA) is one of the causes of heart failure with preserved ejection fraction. Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) and extracellular volume (ECV) fractions is a preferred method to identify CA. However, the requirement of contrast limits its use in renal deficiency patients. Myocardial strain is a promising method without contrast. We sought to assess the early diagnostic and prognostic value of strain. Methods: This retrospective study enrolled 31 patients with systemic amyloidosis (SA) in Peking University First Hospital from January 2014 to January 2019. The patients were categorized into three groups, including 11 CA patients with left ventricular hypertrophy (CA-LVH group), 9 CA patients without LVH (CA-NLVH group), and 11 patients with extracardiac SA (SA group). Strain analysis was performed with CMR images. A least absolute shrinkage and selection operator (LASSO) was used to generate strain score. The receiver operating characteristic (ROC) curve was used to evaluate the early diagnostic efficacy of strain score and other single strain parameter. The primary endpoint was defined as death from all cause or rehospitalization for heart failure. A Cox proportional hazards model was used to assess the index value on the prognosis. Results: In CA patients, as the left ventricular wall thickens, the global and regional strain decrease significantly. A new strain score (strain score = 0.00893 × mid-septal circumferential peak strain + 0.02285 × apical radial peak strain + 0.1541 × apical circumferential peak strain + 0.33097 × epicardial circumferential average peak strain + 0.42232 × endocardial longitudinal average peak strain) generated using LASSO showed that the area under the ROC curve was 0.909. All the patients with outcome events were in CA groups, four were in CA-LVH group and one in CA-NLVH group. New York Heart Association (NYHA) grade [hazard ratio (HR) =14.29, 95% confidence interval (CI): 2.34–87.34, P<0.01], brain natriuretic peptide (HR =20.05, 95% CI: 2.21–182.36, P=0.008), cardiac injury biomarker (HR =11.59, 95% CI: 1.03–130.36, P=0.047), E/E' (mitral inflow to mitral relaxation velocity ratio) (HR =1.09, 95% CI: 1.00–1.18, P=0.040), end-systolic left ventricular volume (HR =1.04, 95% CI: 1.00–1.18, P=0.039) and LGE volume (HR =1.11, 95% CI: 1.02–1.20, P=0.012) positively correlate with events. Better renal function (HR =0.92, 95% CI: 0.86–0.98, P=0.011) and ejection fraction (HR =0.94, 95% CI: 0.88–0.99, P=0.027) appear to be protective factors. Although with no statistical difference, the strain damage had a tendency to predict poor prognosis, i.e., mid-ventricular circumferential strain with HR of 1.25 (95% CI: 1.0–1.57, P=0.050) and strain score with HR of 1.30 (95% CI: 0.98–1.73, P=0.067). Conclusions: Myocardial strain decreased in CA patients. The integrated magnetic resonance imaging (MRI) strain score can serve as a useful tool to identify early myocardial involvement in amyloidosis. The strain damage had a tendency to predict poor prognosis.