0363: Acute coronary syndrome complicated with left ventricular diastolic dysfunction: what is the contribution of brain natriuretic peptid?

Abstract

The utility of Brain Natriuretic Peptide (BNP) for detecting leftventricular (LV) diastolic dysfunction in patients presenting an acute coronary syndrome without heart failure symptoms is unclear. In this study, we investigated the relation between BNP plasma levels and LV diastolic dysfunction in patients with postmyocardial infarction without systolic dysfunction. We studied 81 patients (12 women, mean age 55±11.79) admitted in our center for myocardial infarction with or without ST segment elevation. Patients with heart failure symptoms or abnormal systolic function were excluded. LV diastolic function was assessed with conventional Doppler, by means of mitral inflow and with tissue Doppler echocardiography by means of mitral annulus. The ratio of early diastolic transmitral E wave velocities to tissue Doppler mitral annulus early diastolic E’ wave velocities (E/E’), was used to detect LV filling pressures. Patients were divided in three groups according to E/E’ ratios < 10 (group I), E/E’ ratios between 10 and 15 (group II) and E/E’ ratios >15 (group III). Abstract 0109 – Table: Patients’ baseline characteristics Patients’baseline characteristics BMS (n=30) DES (n=300) p Sex, M/F 30/0 30/0 1 Age, y 52,03±6,35 50,2±8,45 0,34 Body mass index*, kg/m 2 25,79±2,56 25,00±2,97 0,28 Hypertension, % 16,66 1,66 1 Dyslipidemia, % 33,33 33,33 1 Diabetes mellitus, % 0 0 1 Family history, % 26,66 6,66 0,07 Cigarette smoking, % 73,33 60 0,41 Previous CAD, Stroke, PAOD, % 0 0 1 Indication of coronary angiography AMI (STEMI/NSTEMI, % 86,66 76,66 0,5 UA, % 13,33 16,66 1 SCAD, % 0 6,66 0,49 Time interval between PCI and blood sampling, d 39,16±7,68 38,73±6,76 0,81 Stent length, mm 16,3±4,24 17,56±5,71 0,33 LVEF, % 58,66±7,30 61,13±6,18 0,16 Drug therapies * Statin, % 100 100 1 ASA, % 100 100 1 Second anti-platelet drug Clopidogrel, % 46,66 43,33 1 Prasugrel, % 53,33 50 1 Ticagrelor, % 0 6,66 0,49 β-blocker, % 85,71 (n=28) 60 (n=25) 0,059 ACE inhibitor, % 0 (n=28) 0 (n=26) 1 OAC, % 0 0 1 Blood tests * LDL cholesterol, g/L 0,75±0,18 0,68±0,19 0,19 HDL cholesterol, g/L 0,39±0,10 0,43±0,11 0,19 Triglyceride, g/L 0,96±0,32 0,93±0,29 0,72 Hemoblogin, g/dl 14,34±0,97 14,4±0,83 0,82 Platelets, G/L 242,93±55,90 239,56±49,61 0,8 Serum creatinine, μmol/L 2,07±2,02 1,39±1,30 0,12 Fasted glycaemia, g/L 0,97±0,11 1,01±0,09 0,14 HbA1c, % 5,74±0,39 5,73±0,40 0,92 Continuous variables are presented as sample mean and standard deviation. P-values reflect comparisons between patients with a BMS and patients with DES and are derived from Student’s t-tests for continuous variables whereas qualitative data were compared with Fisher’s exact test. The characteristics marked with an asterisk were collected on the same day that blood was sampled (one month after PCI) The BNP blood levels were positively correlated significantly with E/E’ ratio (p < 0.02). Patients with elevated LV end diastolic pressure (LVEDP), defined as E/E’ >15 (n = 27) had highest BNP (302±68 pg/ml) levels. E/E’ 10 to 15 group (n = 24) had a mean BNP level of 136.4±27 pg/ml, and those with E/E’ < 10 (n = 29) had 82±20 pg/ml. A BNP value of 107.8 pg/ml had a sensitivity of 89%, a specificity of 61% for predicting E/E’ >15. The area under the ROC curve for BNP to detect any diastolic dysfunction was 0.757. A BNP value of 72.7 pg/ml had a sensitivity of 82.2% and a specificity of 66.7% for detecting a diastolic dysfunction. A rapid assay for BNP can detect the presence of diastolic abnormalities on echocardiography. In patients with preserved systolic function post myocardial infarction, elevated BNP levels might help to reinforce the diagnosis of LV diastolic dysfunction.