Right atrial volume by cardiovascular magnetic resonance predicts mortality in patients with heart failure with reduced ejection fraction

<div><p>Background</p><p>Right Atrial Volume Index (RAVI) measured by echocardiography is an independent predictor of morbidity in patients with heart failure (HF) with reduced ejection fraction (HFrEF). The aim of this study is to evaluate the predictive value of RAVI assessed by cardiac magnetic resonance (CMR) for all-cause mortality in patients with HFrEF and to assess its additive contribution to the validated Meta-Analysis Global Group in Chronic heart failure (MAGGIC) score.</p><p>Methods and results</p><p>We identified 243 patients (mean age 60 ± 15; 33% women) with left ventricular ejection fraction (LVEF) ≤ 35% measured by CMR. Right atrial volume was calculated based on area in two- and four -chamber views using validated equation, followed by indexing to body surface area. MAGGIC score was calculated using online calculator. During mean period of 2.4 years 33 patients (14%) died. The mean RAVI was 53 ± 26 ml/m²; significantly larger in patients with than without an event (78.7±29 ml/m² vs. 48±22 ml/m², p<0.001). RAVI (per ml/m²) was an independent predictor of mortality [HR = 1.03 (1.01–1.04), p = 0.001]. RAVI has a greater discriminatory ability than LVEF, left atrial volume index and right ventricular ejection fraction (RVEF) (C-statistic 0.8±0.08 vs 0.55±0.1, 0.62±0.11, 0.68±0.11, respectively, all p<0.02). The addition of RAVI to the MAGGIC score significantly improves risk stratification (integrated discrimination improvement 13%, and category-free net reclassification improvement 73%, both p<0.001).</p><p>Conclusion</p><p>RAVI by CMR is an independent predictor of mortality in patients with HFrEF. The addition of RAVI to MAGGIC score improves mortality risk stratification.</p></div

Patient Characteristics.

<p>Cerebral vascular accident, CVA, Pro-BNP, pro-brain natriuretic peptide; LDL, low-density lipoprotein; HDL, high density lipoprotein; RVEF, right ventricular ejection fraction; RVSP, right ventricular systolic pressure; mPAP, mean pulmonary artery pressure; LVEF, left ventricular ejection fraction. Measurements of RV and LV volumes, mass, regional wall motion abnormalities, and function were obtained by CMR; TR and PAP by echocardiography.</p><p>Patient Characteristics.</p

Kaplan-meier survival curve comparing patients with RVEF < 35% (n = 48) and RVEF≥ 35% (n = 61) undergoing CABG or valve procedures.

<p>The top curve corresponds to patients with RVEF <35% and the bottom curve to patients with RVEF≥ 35%. The number below each year indicates the number of patients at risk.</p

Analysis of early (≤ 30-d) and long-term (> 30-d) outcomes associated with primary CABG and valve procedures.

<p>Early complications within 30-d include reoperations for bleeding, early valve reoperations, deep sternal infection, early stroke, early transient ischemic attack, pacemaker implantation, myocardial infarction, atrial fibrillation, and renal insufficiency requiring dialysis.</p><p>Analysis of early (≤ 30-d) and long-term (> 30-d) outcomes associated with primary CABG and valve procedures.</p

Preoperative CMR.

<p>Short axis cine views traced right ventricle (A), left ventricle (B) and right ventricle from base to the apex (C) for ejection fraction measurements. Marked region of interest is demonstrated in green.</p

Analysis of early (≤ 30-d) and long-term (> 30-d) outcomes associated with RVEF <35% and RVEF ≥ 35%.

<p>ICU, intensive care unit; IQR, interquartile range; LFT, liver function test; postoperative complications (i.e. reoperations for bleeding, early valve reoperations, deep sternal infection, early stroke, early transient ischemic attack, pacemaker implantation, myocardial infarction, atrial fibrillation and renal insufficiency requiring dialysis).</p><p>Analysis of early (≤ 30-d) and long-term (> 30-d) outcomes associated with RVEF <35% and RVEF ≥ 35%.</p