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The role of left atrial (LA) strain as an imaging biomarker in aortic stenosis is not well established. The aim of this study was to investigate the prognostic performance of phasic LA strain in relation to clinical and echocardiographic variables and N-terminal pro-B-type natriuretic peptide in asymptomatic and minimally symptomatic patients with moderate to severe aortic stenosis and left ventricular ejection fraction50%.LA reservoir strain (LASr), LA conduit strain (LAScd), and LA contractile strain (LASct) were measured using speckle-tracking echocardiography. The primary outcome was a composite of all-cause mortality, heart failure hospitalization, progression to New York Heart Association functional class III or IV, acute coronary syndrome, or syncope. Secondary outcomes 1 and 2 comprised the same end points but excluded acute coronary syndrome and additionally syncope, respectively. The prognostic performance of phasic LA strain cutoffs was evaluated in competing risk analyses, aortic valve replacement being the competing risk.Among 173 patients (mean age, 69 ± 11 years; mean peak transaortic velocity, 4.0 ± 0.8 m/sec), median LASr, LAScd, and LASct were 27% (interquartile range [IQR], 22%-32%), 12% (IQR, 8%-15%), and 16% (IQR, 13%-18%), respectively. Over a median of 2.7 years (IQR, 1.4-4.6 years), the primary outcome and secondary outcomes 1 and 2 occurred in 66 (38%), 62 (36%), and 59 (34%) patients, respectively. LASr20%, LAScd6%, and LASct12% were identified as optimal cutoffs of the primary outcome. In competing risk analyses, progressing from echocardiographic to echocardiographic-clinical and combined models incorporating N-terminal pro-B-type natriuretic peptide, LA strain parameters outperformed other key echocardiographic variables and significantly predicted clinical outcomes. LASr20% was associated with the primary outcome and secondary outcome 1, LAScd6% with all clinical outcomes, and LASct12% with secondary outcome 2. LAScd6% had the highest specificity (95%) and positive predictive value (82%) for the primary outcome, and competing risk models incorporating LAScd6% had the best discriminative value.In well-compensated patients with moderate to severe aortic stenosis and preserved left ventricular ejection fractions, LA strain was superior to other echocardiographic indices and incremental to N-terminal pro-B-type natriuretic peptide for risk stratification. LAScd6%, LASr20%, and LASct12% identified patients at higher risk for adverse outcomes.

Aims: Left ventricular ejection fraction is the conventional measure used to guide heart failure management, regardless of underlying etiology. Left ventricular global longitudinal strain (LV-GLS) by speckle tracking echocardiography (STE) is a more sensitive measure of intrinsic myocardial function. We aim to establish LV-GLS as a marker of replacement myocardial fibrosis on cardiovascular magnetic resonance (CMR) and validate the prognostic value of LV-GLS thresholds associated with fibrosis. Methods and results: LV-GLS thresholds of replacement fibrosis were established in the derivation cohort: 151 patients (57 ± 10 years; 58% males) with hypertension who underwent STE to measure LV-GLS and CMR. Prognostic value of the thresholds was validated in a separate outcome cohort: 261 patients with moderate-severe aortic stenosis (AS; 71 ± 12 years; 58% males; NYHA functional class I–II) and preserved LVEF ≥50%. Primary outcome was a composite of cardiovascular mortality, heart failure hospitalization, and myocardial infarction. In the derivation cohort, LV-GLS demonstrated good discrimination (c-statistics 0.74 [0.66–0.83]; P < 0.001) and calibration (Hosmer-Lemeshow χ2 = 6.37; P = 0.605) for replacement fibrosis. In the outcome cohort, 47 events occurred over 16 [3.3, 42.2] months. Patients with LV-GLS > −15.0% (corresponding to 95% specificity to rule-in myocardial fibrosis) had the worst outcomes compared to patients with LV-GLS < −21.0% (corresponding to 95% sensitivity to rule-out myocardial fibrosis) and those between −21.0 and −15.0% (log-rank P < 0.001). LV-GLS offered independent prognostic value over clinical variables, AS severity and echocardiographic LV mass and E/e′. Conclusion: LV-GLS thresholds associated with replacement myocardial fibrosis is a novel approach to risk-stratify patients with AS and preserved LVEF., Graphical Abstract Thresholds of echocardiographic left ventricular global longitudinal strain (GLS) that are associated with replacement myocardial fibrosis risk-stratify patients with aortic stenosis and preserved left ventricular ejection fraction. Some images in the figure were created with BioRender.com.

Background Acute myocardial infarction (AMI) is a leading cause of mortality in Asia. However, quantitative risk scores to predict mortality after AMI were developed without the participation of Asian countries. Methods We evaluated the performance of the Global Registry of Acute Coronary Events (GRACE) in-hospital mortality risk score, directly and after recalibration, in a large Singaporean cohort representing 3 major Asian ethnicities. Results The GRACE cohort included 11,389 patients, predominantly of European descent, hospitalized for AMI or unstable angina from 2002 to 2003. The Singapore cohort included 10,100 Chinese, 3,005 Malay, and 2,046 Indian patients hospitalized for AMI from 2002 to 2005.Using the original GRACE score, predicted in-hospital mortality was 2.4% (Chinese), 2.0% (Malay), and 1.6% (Indian). However, observed in-hospital mortality was much greater at 9.8% (Chinese), 7.6% (Malay), and 6.4% (Indian). The c statistic for Chinese, Malays, and Indians was 0.86, 0.86, and 0.84, respectively, and the Hosmer-Lemeshow statistic was 250, 56, and 41, respectively. Recalibration of the GRACE score, using the mean-centered constants derived from the Singapore cohort, did not change the c statistic but substantially improved the Hosmer-Lemeshow statistic to 90, 24, and 18, respectively. The recalibrated GRACE score predicted in-hospital mortality as follows: 7.7% (Chinese), 6.0% (Malay), and 5.2% (Indian). Conclusion In this large cohort of 3 major Asian ethnicities, the original GRACE score, derived from populations outside Asia, underestimated in-hospital mortality after AMI. Recalibration improved risk estimation substantially and may help adapt externally developed risk scores for local practice.

We evaluated diastolic filling patterns using Doppler echocardiography in 520 consecutive patients referred to our laboratory for transthoracic echocardiograms retrospectively and applied the standard guidelines used to characterize left ventricular (LV) diastolic function. Patients were classified by the Canadian consensus guidelines using transmitral and pulmonary venous Doppler echocardiographic parameters to have normal diastolic function or mild (abnormal relaxation), mild-to-moderate, moderate (pseudonormal), or severe (restrictive) diastolic dysfunction. LV diastolic dysfunction was present in 290 (56%) patients, whereas 167 (45%) patients with a normal LV ejection fraction had abnormal diastolic function. Patients with progressively more abnormal diastolic patterns had greater structural abnormalities with larger left atrial and LV size and lower LV ejection fractions. In the subset of patients with clinical evidence of congestive heart failure (99 patients), the prevalence of primary diastolic heart failure was 38% and most patients had underlying coronary or hypertensive heart disease. Standard guidelines of Doppler echocardiographic parameters allow semiquantitation of diastolic function and can be applied to studying large number of patients in a large clinical practice. (J Am Soc Echocardiogr 2002;15:1237-44.)

Background: With the ever-increasing number of acutely ill patients with cardiac disease that need intensive monitoring and limited resources in coronary care unit (CCU), there is a need to ensure appropriate admission to CCU. Studies have shown that Killip 1 patients who had successful primary percutaneous coronary intervention (PPCI) for ST Elevation Myocardial Infarction (STEMI) can be admitted safely to a step-down unit. However, Killip class was a subjective assessment. We attempt to compare TIMI risk index {TRI = [heart rate X (age/10)2]/systolic blood pressure} versus Killip Class at presentation in determining the need of admission to CCU for STEMI patient after successful PPCI. TRI was a robust predictor (for STEMI patients on irst arrival in hospital) and high discriminatory capacity of in-hospital events in each of the ive risk subgroups.