Cardiac Dysfunction, Congestion and Loop Diuretics: their Relationship to Prognosis in Heart Failure.
BACKGROUND
Diuretics are the mainstay of treatment for congestion but concerns exist that they adversely affect prognosis. We explored whether the relationship between loop diuretic use and outcome is explained by the underlying severity of congestion amongst patients referred with suspected heart failure.


RESULTS
Of 1190 patients, 712 had a left ventricular ejection fraction (LVEF) ≤50 %, 267 had LVEF >50 % with raised plasma NTproBNP (>400 ng/L) and 211 had LVEF >50 % with NTproBNP ≤400 ng/L; respectively, 72 %, 68 % and 37 % of these groups were treated with loop diuretics including 28 %, 29 % and 10 % in doses ≥80 mg furosemide equivalent/day. Compared to patients with cardiac dysfunction (either LVEF ≤50 % or NT-proBNP >400 ng/L) but not taking a loop diuretic, those taking a loop diuretic were older and had more clinical evidence of congestion, renal dysfunction, anaemia and hyponatraemia. During a median follow-up of 934 (IQR: 513-1425) days, 450 patients were hospitalized for HF or died. Patients prescribed loop diuretics had a worse outcome. However, in multi-variable models, clinical, echocardiographic (inferior vena cava diameter), and biochemical (NTproBNP) measures of congestion were strongly associated with an adverse outcome but not the use, or dose, of loop diuretics.


CONCLUSIONS
Prescription of loop diuretics identifies patients with more advanced features of heart failure and congestion, which may account for their worse prognosis. Further research is needed to clarify the relationship between loop diuretic agents and outcome; imaging and biochemical measures of congestion might be better guides to diuretic dose than symptoms or clinical signs.
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK. pierpaolo.pellicori@hey.nhs.uk.
Pierpaolo
P
Pellicori
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
John G F
JG
Cleland
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
Jufen
J
Zhang
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
Anna
A
Kallvikbacka-Bennett
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
Alessia
A
Urbinati
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
Parin
P
Shah
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
Syed
S
Kazmi
Department of Cardiology, Hull and East Yorkshire Medical Research and Teaching Centre, Castle Hill Hospital, Hull York Medical School, Cottingham, Kingston upon Hull, HU16 5JQ, UK.
Andrew L
AL
Clark
D000368:Aged; D000369:Aged, 80 and over; D004232:Diuretics / Q000627:therapeutic use*; D004452:Echocardiography; D005260:Female; D006333:Heart Failure / Q000097:blood / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000097:blood; D010446:Peptide Fragments / Q000097:blood; D011379:Prognosis; D016896:Treatment Outcome; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging; D016277:Ventricular Function, Left / Q000187:drug effects
D004232:Diuretics; D010446:Peptide Fragments; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
Congestion; Heart failure; Loop diuretic; Prognosis