[Impact of optimal medical therapy on the arrhythmias and heart rate variability detected with 24 hour Holter in a series of patients from a heart failure clinic].
Pharmacological treatment of heart failure (HF) patients usually induces improvements in their functional class (FC). Heart rate variability and Holter-detected arrhythmias are sudden cardiac death predictors and should be evaluated in the presence of optimal medical treatment.


METHODS
We conducted a prospective, observational and linear study to evaluate ventricular arrhythmia presence and heart rate variability through 24-hr Holter. A first recording was made upon admission to the HF clinic and the second was obtained when a stable FC was reached or optimal medication doses where attained.


RESULTS
We have controls among 47 patients 11.6 +/- 8.1 months after the enrollment Holter. We have 26 (55.3%) men, with an average age of 60.2 +/- 13.9 years. The main ejection fraction (EF) went from 31.9 to 37.4% during follow-up (p = 0.01). At enrollment, 44.7% of our patients were in a FC I, 27.7% in FC II and 27.7% in FC III. At the end of follow-up, 67.4% were in FC I, 27.9% in FC II and 4.7% in FC III. Time-domain variability did not show significant changes and remained in normal average values. Premature atrial contractions diminished (324.1 +/- 811.1 vs. 316 +/- 809.2) but the ventricular ones went from 1,493.6 +/- 3,530.9 in 24 hours, to 1,582.4 +/- 4,394.5 (p = ns) during control, among those with an EF < 40% and SDNN < 100 ms, we found an increase from 7,026.6 +/- 12,168.8 to 9,336 +/- 16,137.8 PVC's in 24-hours (p = 0.008).


CONCLUSIONS
Optimal medical therapy for heart failure can positively change certain aspects of these patients, but it does not improve the arrhythmic sudden death risk profile.
Cárdenas
Enrique
E
Clínica de Arritmias y Marcapasos, Departamento de Cardiología, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, México, DF.
Asensio
Enrique
E
Orea
Arturo
A
Castillo
Lilia
L
Narváez
René
R
Dorantes
Joel
J
Rebollar
Verónica
V
Hernández
Pablo
P
Nájera
Emma
E
Oseguera
Jorge
J
D001145:Arrhythmias, Cardiac / Q000209:etiology* / Q000503:physiopathology*; D002300:Cardiac Care Facilities; D015716:Electrocardiography, Ambulatory; D005260:Female; D006333:Heart Failure / Q000150:complications* / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies