Oh, Jae K.

Introduction: Patients with heart failure with preserved ejection fraction (HFpEF) may have elevated left ventricular filling pressure with exercise (LVFP-ex), despite normal LVFP at rest. We aimed to assess the diagnostic value of resting left atrial strain (LAS) in detecting elevated LVFP-ex in dyspneic patients evaluated by exercise stress echocardiography. Methods: We performed 2D-speckle tracking analysis for LAS in 669 consecutive patients (mean age 64 ± 14, men 53%) who underwent treadmill echocardiography evaluation and had LV ejection fraction ≥50%. Assessment of LVFP at rest was based on the 2016 ASE Guidelines for diastolic function assessment. We used the 2019 ESC HFA-PEEF diagnostic algorithm to define elevated LVFP-ex (early mitral inflow wave/septal early diastolic tissue velocity (E/e’) ≥ 15 after exercise) and calculate a continuous HFA-PEEF score. Results: LAS reservoir was lowest in patients with elevated LVFP at rest (n=81) and lower in those with normal resting FP who developed elevated LVFP-ex (n=108) compared to those who maintained normal LVFP-ex (29.0 ± 5.2% vs. 33.1 ± 5.0% vs.39.3 ± 4.8%, p < 0.001). In patients with normal or indeterminate LVFP at rest (n=587), LAS reservoir and pre-exercise HFA-PEEF score demonstrated an area-under-the-curve (AUC) of 0.82 and 0.7 respectively for elevated LVFP-ex. There was a 28% higher odds of developing elevated LVFP-ex per 1% decrease in LAS reservoir (odds ratio, 95%CI: 0.78, 0.74 - 0.82). In patients with the intermediate score (n=461), 123 patients developed elevation in LVFP with exercise and were classified as having HFpEF per the diagnostic algorithm. Addition of LAS reservoir improved the predictive value of HFA-PEEF score for HFpEF (AUC increased from 0.71 to 0.80, p for ΔAUC =0.01). Conclusions: LAS reservoir has a potential to identify patients at intermediate-risk for HFpEF who may develop elevated LVFP with exercise only, and therefore a promising parameter to aid in the diagnosis of HFpEF when exercise testing is not feasible.

Introduction: A low cardiac power output (CPO), measured invasively, identifies critically ill patients at increased risk of mortality. CPO can also be measured non-invasively with transthoracic echocardiography (TTE), although prognostic data in critically ill patients is not available. Hypothesis: Reduced CPO measured by TTE is associated with increased hospital mortality in cardiac intensive care unit (CICU) patients. Methods: Using a database of CICU patients admitted between 2007 and 2018, we identified patients with TTE within one day (before or after) of CICU admission who had data necessary for calculation of CPO. Multivariable logistic regression determined the relationship between CPO and adjusted hospital mortality. Results: We included 5,585 patients with a mean age of 68.3±14.8 years, including 36.7% females. Admission diagnoses included acute coronary syndrome (ACS) in 57%, heart failure (HF) in 50%, cardiac arrest (CA) in 12%, and cardiogenic shock (CS) in 13%. The mean left ventricular ejection fraction (LVEF) was 47±16%, and the mean CPO was 1.0±0.4 W. CPO was inversely associated with the risk of hospital mortality (Figure A), including among patients with ACS, HF, and CS (Figure B). On multivariable analysis, lower CPO was associated with higher hospital mortality (OR 0.96 per 0.1 W, 95% CI 0.0.93-0.99, p=0.03). Hospital mortality was highest in patients with low CPO coupled with reduced LVEF, increased vasopressor requirements, or higher admission lactate. Hospital mortality was higher among patients with a CPO <0.6 W (adjusted OR 1.57, 95% CI 1.13-2.19, p = 0.007), particularly in the presence of admission lactate level >4 mmol/L (50.9%). Conclusions: Echocardiographic CPO was inversely associated with hospital mortality in CICU patients, particularly among patients with increased lactate and vasopressor requirements. Routine measurement of CPO provides important information beyond LVEF and should be considered in CICU patients.

Echocardiography (Echo), a widely available, noninvasive, and portable bedside imaging tool, is the most frequently used imaging modality in assessing cardiac anatomy and function in clinical practice. On the other hand, its operator dependability introduces variability in image acquisition, measurements, and interpretation. To reduce these variabilities, there is an increasing demand for an operator- and interpreter-independent Echo system empowered with artificial intelligence (AI), which has been incorporated into diverse areas of clinical medicine. Recent advances in AI applications in computer vision have enabled us to identify conceptual and complex imaging features with the self-learning ability of AI models and efficient parallel computing power. This has resulted in vast opportunities such as providing AI models that are robust to variations with generalizability for instantaneous image quality control, aiding in the acquisition of optimal images and diagnosis of complex diseases, and improving the clinical workflow of cardiac ultrasound. In this review, we provide a state-of-the art overview of AI-empowered Echo applications in cardiology and future trends for AI-powered Echo technology that standardize measurements, aid physicians in diagnosing cardiac diseases, optimize Echo workflow in clinics, and ultimately, reduce healthcare costs.

Background Impaired right ventricular (RV) pulmonary artery coupling has been associated with higher mortality in patients with chronic heart disease, but few studies have examined this metric in critically ill patients. We sought to evaluate the association between RV pulmonary artery coupling, defined by the ratio of tricuspid annular peak systolic tissue Doppler velocity (TASV)/estimated RV systolic pressure (RVSP), and mortality in cardiac intensive care unit patients. Methods and Results Using a database of unique cardiac intensive care unit admissions from 2007 to 2018, we included patients with TASV/RVSP ratio measured within 1 day of hospitalization. Hospital mortality was analyzed using multivariable logistic regression, and 1‐year mortality was analyzed using multivariable Cox proportional‐hazards analysis. We included 4259 patients with a mean age of 69±15 years (40.1% women). Admission diagnoses included acute coronary syndrome in 56%, heart failure in 52%, respiratory failure in 24%, and cardiogenic shock in 12%. The mean TASV/RVSP ratio was 0.31±0.14, and in‐hospital mortality occurred in 7% of patients. Higher TASV/RVSP ratio was associated with lower in‐hospital mortality (adjusted unit odds ratio, 0.68 per each 0.1‐unit higher ratio; 95% CI, 0.58–0.79; P <0.001) and lower 1‐year mortality among hospital survivors (adjusted unit hazard ratio, 0.83 per each 0.1‐unit higher ratio; 95% CI, 0.77–0.90; P <0.001). Stepwise decreases in hospital and 1‐year mortality were observed in each higher TASV/RVSP quintile. The TASV/RVSP ratio remained associated with mortality after adjusting for left ventricular systolic and diastolic function. Conclusions A low TASV/RVSP ratio is associated with increased short‐term and long‐term mortality among cardiac intensive care unit patients, emphasizing importance of impaired RV pulmonary artery coupling as a determinant of poor prognosis. Further study is required to determine whether interventions to optimize RV pulmonary artery coupling can improve outcomes.

Abstract Aims Early detection of aortic stenosis (AS) is becoming increasingly important with a better outcome after aortic valve replacement in asymptomatic severe AS patients and a poor outcome in moderate AS. We aimed to develop artificial intelligence-enabled electrocardiogram (AI-ECG) using a convolutional neural network to identify patients with moderate to severe AS. Methods and results Between 1989 and 2019, 258 607 adults [mean age 63 ± 16.3 years; women 122 790 (48%)] with an echocardiography and an ECG performed within 180 days were identified from the Mayo Clinic database. Moderate to severe AS by echocardiography was present in 9723 (3.7%) patients. Artificial intelligence training was performed in 129 788 (50%), validation in 25 893 (10%), and testing in 102 926 (40%) randomly selected subjects. In the test group, the AI-ECG labelled 3833 (3.7%) patients as positive with the area under the curve (AUC) of 0.85. The sensitivity, specificity, and accuracy were 78%, 74%, and 74%, respectively. The sensitivity increased and the specificity decreased as age increased. Women had lower sensitivity but higher specificity compared with men at any age groups. The model performance increased when age and sex were added to the model (AUC 0.87), which further increased to 0.90 in patients without hypertension. Patients with false-positive AI-ECGs had twice the risk for developing moderate or severe AS in 15 years compared with true negative AI-ECGs (hazard ratio 2.18, 95% confidence interval 1.90–2.50). Conclusion An AI-ECG can identify patients with moderate or severe AS and may serve as a powerful screening tool for AS in the community.

Background Myocardial fibrosis is an important contributor for development of diastolic dysfunction. We investigated the impact of sirolimus as primary immunosuppression on diastolic dysfunction and fibrosis progression among heart transplantation recipients. Methods and Results In 100 heart transplantation recipients who were either treated with a calcineurin inhibitor (CNI) (n=51) or converted from CNI to sirolimus (n=49), diastolic function parameters were assessed using serial echocardiograms and right heart catheterizations. Myocardial fibrosis was quantified on serial myocardial biopsies. After 3 years, lateral e′ increased within the sirolimus group but decreased in the CNI group (0.02±0.04 versus −0.02±0.04 m/s delta change; P =0.003, respectively). Both pulmonary capillary wedge pressure and diastolic pulmonary artery pressure significantly decreased in the sirolimus group but remained unchanged in the CNI group (−1.50±2.59 versus 0.20±2.20 mm Hg/year; P =0.02; and −1.72±3.39 versus 0.82±2.59 mm Hg/year; P =0.005, respectively). A trend for increased percentage of fibrosis was seen in the sirolimus group (8.48±3.17 to 10.10±3.0%; P =0.07) as compared with marginally significant progression in the CNI group (8.76±3.87 to 10.56±4.34%; P =0.04). The percent change in fibrosis did not differ significantly between the groups (1.62±4.67 versus 1.80±5.31%, respectively; P =0.88). Conclusions Early conversion to sirolimus is associated with improvement in diastolic dysfunction and filling pressures as compared with CNI therapy. Whether this could be attributed to attenuation of myocardial fibrosis progression with sirolimus treatment warrants further investigation.

Background: Reduced left ventricular stroke work index (LVSWI) has been associated with adverse outcomes in several populations of patients with chronic heart disease, but no prior studies have examined this metric in cardiac intensive care unit (CICU) patients. We sought to determine whether a low LVSWI, as measured noninvasively using transthoracic echocardiography, is associated with higher mortality in CICU patients. Methods: Using a database of unique Mayo Clinic CICU admissions from 2007 to 2018, we identified patients with LVSWI measured by transthoracic echocardiography within 1 day of CICU admission. Hospital mortality was analyzed using multivariable logistic regression, and 1-year mortality was analyzed using multivariable Cox proportional-hazards analysis, adjusted for left ventricular ejection fraction and known predictors of hospital mortality. Results: We included 4536 patients with a mean age of 68±14 years (36% women). Admission diagnoses (not mutually exclusive) included acute coronary syndrome in 62%, heart failure in 46%, and cardiogenic shock in 11%. The mean LVSWI was 38±14 g×min/m 2 , and in-hospital mortality occurred in 6% of patients. LVSWI had better discrimination for hospital mortality than left ventricular ejection fraction ( P <0.001 by De Long test). Higher LVSWI was associated with lower in-hospital mortality (adjusted odds ratio, 0.72 per 10 g×min/m 2 higher [95% CI, 0.61–0.84]; P <0.001) and lower 1-year mortality (adjusted hazard ratio, 0.812 per 1 g×min/m 2 higher [95% CI, 0.759–0.868]; P <0.001). Stepwise decreases in hospital and 1-year mortality were observed with higher LVSWI. Conclusions: Low LVSWI, reflecting poor left ventricular systolic and diastolic performance, is associated with increased short-term and long-term mortality among CICU patients. This emphasizes the importance of Doppler transthoracic echocardiography as a predictor of outcomes among critically ill patients. Further study is required to determine whether early interventions to optimize LVSWI can improve outcomes in the CICU setting.

Abstract Aims Increased medial mitral annulus early diastolic velocity (e′) plays an important role in the echocardiographic diagnosis of constrictive pericarditis (CP) and mitral e′ velocity is also a marker of underlying myocardial disease. We assessed the prognostic implication of mitral e′ for long-term mortality after pericardiectomy in patients with CP. Methods and results We studied 104 surgically confirmed CP patients who underwent echocardiography and cardiac catheterization within 7 days between 2005 and 2013. Patients were classified as primary CP (n = 45) or mixed CP (n = 59) based on the clinical history of concomitant myocardial disease. On multivariable analysis, medial e′ velocity and mean pulmonary artery pressure were independently associated with long-term mortality post-pericardiectomy. There were significant differences in survival rates among the groups divided by cut-off values of 9.0 cm/s and 29 mmHg for medial e′ and mean pulmonary artery pressure, respectively (both P &lt; 0.001). Ninety-two patients (88.5%) had elevated pulmonary artery wedge pressure (PAWP) (≥15 mmHg); there was no significant correlation between medial E/e′ and PAWP (r = 0.002, P = 0.998). However, despite the similar PAWP between primary CP and mixed CP groups (21.6 ± 5.4 vs. 21.2 ± 5.8, P = 0.774), all primary CP individuals with elevated PAWP had medial E/e′ &lt;15 as opposed to 34 patients (57.6%) in the mixed CP group (P &lt; 0.001). Conclusion Increased mitral e′ velocity is associated with better outcomes in patients with CP. A paradoxical distribution of the relationship between E/e′ and PAWP is present in these patients but there is no direct inverse correlation between them.