P339The factors associated with death, transplantation and appropriate defibrillators shocks in patients with dilated cardiomyopathy depending on its etiology
Authors: Blagova O V , Solovjeva E A , Sedov V P , Kogan E A , Zaitsev A Y U , Nedostup A V 
Published: October 2019

Abstract

Purpose
To study the predictors of death, transplantation and appropriate shocks (AS) of defibrillators in patients with dilated cardiomyopathy (DCM) depending on its etiology.

Methods
In 300 patients with DCM syndrome (206 males, 47.6±12.7 years, the average left ventricle (LV) end-diastolic diameter 6.4 [5.9; 7.1] cm, LV ejection fraction (EF) 32 [25; 40] %) were performed viral genome (real-time PCR) and anti-heart antibodies investigation, ECG, Holter, Echo-CG, cardiac CT, MRI, coronary angiography, and also morphological study of myocardium in 103 (34%) patients. Defibrillators were implanted in 80 (26.7%) patients: 47 ICD, 33 CRTD. The follow-up was 15 [6; 42] months.

Results
The following causes of DCM syndrome have been identified: the isolated myocarditis (n=164, 54.7%), the primary/genetic DCM (n=58, 19.3%), the genetic DCM with myocarditis (n=71, 23.7%), peripartum (n=1, 0.3%) and chemotherapy-induced cardiomyopathy (n=5, 1.7%), arteriovenous malformation (n=1, 0.3%). Genetic forms of DCM were represented by noncompact myocardium (n=64), ARVC (n=12), TTR-amyloidosis (n=1), myopathy (n=6). The pathogenic mutations in the genes LMNA (n=1), DES (n=2), DSP (n=2), EMD (n=2), PKP2 (n=1), MUH7+MyBPC3 (n=2), MyBPC3 (n=4) were detected. The AS rate was 23.8%. The only predictor of AS was identified the genetic/primary nature of DCM, that is diagnosed in 100% of patients with AS in comparison with 57% in patients without AS, p<0.001 (AUC 0.716, RR 1.76, 95% CI 1.43–2.17). The patients with AS had higher LVEF (35.7±10.3 vs 28.3±9.7%, p<0.01), smaller LV end-diastolic diameter (6.2±0.6 vs 6.8±0.9 cm, p<0.01), low QRS voltage (39 vs 13%, p=0.077), absence of LV hypertrophy on ECG (79 vs 52%, p<0.05), underuse of beta-blockers (74 vs 92%), sustained VT (32 vs 4%, p<0.05), but not isolated unsustained VT (54 vs 70%, p>0.05). The mortality in patients with DCM was 19.7%, rate of transplantation 4.3%, death + transplantation 23.0%, SCD 2.7%. There were no differences depending on devises implantation due to adequate selection to procedure. The following factors were associated with mortality: high NYHA class and severe heart dysfunction, absence of improvement after start of therapy, acute debut of symptoms, viral genome in the myocardium, absence of anti-heart antibodies, absence of immunosuppressive therapy, beta-blockers and ACE inhibitors and MRA. The predictors of transplantation were genetic/primary DCM, younger age (38.3±10.3 vs 48.0±12.7, p<0.05), low QRS voltage, more frequent PVBs and unsustained VT, severe restrictive dysfunction, absence of immunosuppressive therapy, beta-blockers, and sustained reduction of EF.

Conclusions
The etiology of DCM syndrome plays a key role in the prognosis and should be considered when selecting patients for ICD and heart transplantation. The genetic nature of DCM is the more important predictor of shocks than EF. The total mortality is clearly associated with resistant myocardial dysfunction.