Clinical relevance of short-term day-time breathing disorders in chronic heart failure patients.
BACKGROUND
Periodic Breathing (PB, waxing and waning of tidal volume in which hyperventilation alternates with periods of apnoea or hypopnoea), is common during sleep and wakefulness in patients with Heart Failure (HF) and may increase mortality.


OBJECTIVE
To assess the effect of short-term, day-time PB on prognosis, in HF patients.


METHODS
We prospectively studied 380 consecutive HF referrals who had a 10 min, supine day-time respiratory recording. We related PB (adjusted for known predictors) to total cardiac mortality, during a median follow-up of 41 months.


RESULTS
Day-time PB occurred in 145/380 patients who had more severe HF and more compromised left ventricular function (p<0.005). Survival curves began to separate after 10 months and diverged steadily over the next 4 years with a cumulative risk of 41% (PB) vs 26% (No-PB), p=0.002. PB was independently predictive of increased cardiac mortality when entered into a clinical prognostic model (including NYHA Class, LVEF, LVEDD, Systolic Arterial Pressure, beta-blocker treatment, peak VO2 and blood urea) with a RR: 1.8, 95% CI 1.20-2.81.


CONCLUSIONS
In advanced HF the presence of PB during a short day-time recording adds to known predictors of cardiac mortality. This may have practical implications for trials of HF therapy.
La Rovere
Maria Teresa
MT
Divisione di Cardiologia, Pneumologia e Bioingegneria, Fondazione Salvatore Maugeri, IRCCS, Istituto Scientifico di Montescano, 27040 Montescano, (Pavia), Italy. mtlarovere@fsm.it
Pinna
Gian Domenico
GD
Maestri
Roberto
R
Robbi
Elena
E
Mortara
Andrea
A
Fanfulla
Francesco
F
Febo
Oreste
O
Sleight
Peter
P
D000328:Adult; D009202:Cardiomyopathies / Q000150:complications / Q000401:mortality*; D015331:Cohort Studies; D005260:Female; D006333:Heart Failure / Q000150:complications / Q000401:mortality*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010507:Periodicity; D011379:Prognosis; D011446:Prospective Studies; D012119:Respiration; D012140:Respiratory Tract Diseases / Q000150:complications*; D012307:Risk Factors; D013997:Time Factors