Markers of Myocardial Damage Predict Mortality in Patients With Aortic Stenosis.

BACKGROUND: Cardiovascular magnetic resonance (CMR) is increasingly used for risk stratification in aortic stenosis (AS). However, the relative prognostic power of CMR markers and their respective thresholds remains undefined. OBJECTIVES: Using machine learning, the study aimed to identify prognostically important CMR markers in AS and their thresholds of mortality. METHODS: Patients with severe AS undergoing AVR (n = 440, derivation; n = 359, validation cohort) were prospectively enrolled across 13 international sites (median 3.8 years' follow-up). CMR was performed shortly before surgical or transcatheter AVR. A random survival forest model was built using 29 variables (13 CMR) with post-AVR death as the outcome. RESULTS: There were 52 deaths in the derivation cohort and 51 deaths in the validation cohort. The 4 most predictive CMR markers were extracellular volume fraction, late gadolinium enhancement, indexed left ventricular end-diastolic volume (LVEDVi), and right ventricular ejection fraction. Across the whole cohort and in asymptomatic patients, risk-adjusted predicted mortality increased strongly once extracellular volume fraction exceeded 27%, while late gadolinium enhancement >2% showed persistent high risk. Increased mortality was also observed with both large (LVEDVi >80 mL/m2) and small (LVEDVi ≤55 mL/m2) ventricles, and with high (>80%) and low (≤50%) right ventricular ejection fraction. The predictability was improved when these 4 markers were added to clinical factors (3-year C-index: 0.778 vs 0.739). The prognostic thresholds and risk stratification by CMR variables were reproduced in the validation cohort. CONCLUSIONS: Machine learning identified myocardial fibrosis and biventricular remodeling markers as the top predictors of survival in AS and highlighted their nonlinear association with mortality. These markers may have potential in optimizing the decision of AVR.

Myocardial strain and symptom severity in severe aortic stenosis: insights from cardiovascular magnetic resonance.

BACKGROUND: Symptomatic severe aortic stenosis (AS) is a class I indication for replacement in patients when left ventricular ejection fraction (LVEF) is preserved. However, symptom reporting is often equivocal and decision making can be challenging. We aimed to quantify myocardial deformation using cardiovascular magnetic resonance (CMR) in patients classified by symptom severity. METHODS: Forty-two patients with severe AS referred to heart valve clinic were studied using tagged CMR imaging. All had preserved LVEF. Patients were grouped by symptoms as either "none/mild" (n=21, NYHA class I, II) or "significant" (n=21, NYHA class III, IV, angina, syncope) but were comparable for age (72.8±5.4 vs. 71.0±6.8 years old, P=0.345), surgical risk (EuroSCORE II: 1.90±1.7 vs. 1.31±0.4, P=0.302) and haemodynamics (peak aortic gradient: 55.1±20.8 vs. 50.4±15.6, P=0.450). Thirteen controls matched in age and LVEF were also studied. LV circumferential strain was calculated using inTag© software and longitudinal strain using feature tracking analysis. RESULTS: Compared to healthy controls, patients with severe AS had significantly worse longitudinal and circumferential strain, regardless of symptom status. Patients with "significant" symptoms had significantly worse peak longitudinal systolic strain rates (-83.352±24.802%/s vs. -106.301±43.276%/s, P=0.048) than those with "no/mild" symptoms, with comparable peak longitudinal strain (PLS), peak circumferential strain and systolic and diastolic strain rates. CONCLUSIONS: Patients with severe AS who have no or only mild symptoms exhibit comparable reduction in circumferential and longitudinal fibre function to those with significant symptoms, in whom AVR is clearly indicated. Given these findings of equivalent subclinical dysfunction, reportedly borderline symptoms should be handled cautiously to avoid potentially adverse delays in intervention.

Primary cardiac tumors: 32 years of experience from a Spanish tertiary surgical center.

INTRODUCTION: Primary cardiac tumors are rare entities with an autopsy frequency ranging between 0.001% and 0.3%. Our objective was to review 32 years of experience from a Spanish tertiary surgical center. METHOD: We collected data on 73 patients with a histopathological diagnosis of a primary cardiac tumor in a retrospective analysis from 1979 to 2012. Tissue samples were obtained either at surgery or from necropsy and subsequently divided into benign and malignant groups. RESULTS: Benign neoplasms accounted for 84.9% of cases. The average age at diagnosis was 61 years, and tumors were twice as frequent among women. It was an incidental finding in one quarter of patients. In symptomatic patients, the typical presentation was of cardioembolic stroke or of congestive symptoms. Myxoma (93.5%) was the most common diagnosis, typically affecting the left atrium (74.2%). Surgical resection was curative for 95% of these patients. Malignant tumors represented 15.1% of cases with an average age at diagnosis of 50 years. Over 90% of these patients were symptomatic at presentation with the cardinal symptom being heart failure. Undifferentiated sarcoma was the most frequent malignant tumor (36.4%). Less than 20% of patients were alive 1 year after diagnosis despite the treatment. CONCLUSIONS: In our study, primary cardiac tumors were insidious. The most common was left atrial myxoma in which surgical resection was considered curative. Undifferentiated sarcoma was the most frequent malignant tumor. Malignant neoplasms carried a worse prognosis with unsuccessful total excision and the presence of metastatic disease being markers of an adverse outcome.