TY - JOUR
T1 - Baroreflex sensitivity, but not heart rate variability, is reduced in patients with life-threatening ventricular arrhythmias long after myocardial infarction
AU - De Ferrari, Gaetano M.
AU - Landolina, Maurizio
AU - Mantica, Massimo
AU - Manfredini, Ruggero
AU - Schwartz, Peter J.
AU - Lotto, Antonio
PY - 1995
Y1 - 1995
N2 - Low values of heart rate variability (HRV, a marker of vagal tone) and baroreflex sensitivity (BRS, a marker of vagal reflexes) identify patients at higher risk soon after myocardial infarction (MI). However, it is still unknown whether HRV and BRS correlate with malignant arrhythmias after the recovery from the transient post-MI autonomic disturbance. This study assessed whether HRV and BRS would differ in patients with malignant ventricular arrhythmias occurring long after MI compared with those in a control population. Twenty-eight patients entered the study: 14 patients with episodes of sustained ventricular tachycardia or ventricular fibrillation occurring more than 1 year after MI, age (mean ± SEM) 64 ± 2 years, and left ventricular ejection fraction 34% ± 3% ( VT VF group) were compared with 14 similar patients with no ventricular tachycardia (control group). Mean RR interval was not different in the two groups (844 ± 37 msec in VT VF and 892 ± 24 msec in control group). Also, no difference was found in any time- or frequency-domain measure of heart rate variability. However, patients in the VT VF group had a significantly lower baroreflex sensitivity compared with patients in the control group (4.2 ± 0.5 vs 8.0 ± 1.1 msec/mm Hg, p = 0.008). Thus BRS but not HRV was reduced in patients with life-threatening ventricular arrhythmias occurring long after MI. A persistent depression of vagal reflexes may play a role in the occurrence of malignant arrhythmias, and analysis of BRS may potentially be helpful in the identification of patients at high risk long after myocardial infarction.
AB - Low values of heart rate variability (HRV, a marker of vagal tone) and baroreflex sensitivity (BRS, a marker of vagal reflexes) identify patients at higher risk soon after myocardial infarction (MI). However, it is still unknown whether HRV and BRS correlate with malignant arrhythmias after the recovery from the transient post-MI autonomic disturbance. This study assessed whether HRV and BRS would differ in patients with malignant ventricular arrhythmias occurring long after MI compared with those in a control population. Twenty-eight patients entered the study: 14 patients with episodes of sustained ventricular tachycardia or ventricular fibrillation occurring more than 1 year after MI, age (mean ± SEM) 64 ± 2 years, and left ventricular ejection fraction 34% ± 3% ( VT VF group) were compared with 14 similar patients with no ventricular tachycardia (control group). Mean RR interval was not different in the two groups (844 ± 37 msec in VT VF and 892 ± 24 msec in control group). Also, no difference was found in any time- or frequency-domain measure of heart rate variability. However, patients in the VT VF group had a significantly lower baroreflex sensitivity compared with patients in the control group (4.2 ± 0.5 vs 8.0 ± 1.1 msec/mm Hg, p = 0.008). Thus BRS but not HRV was reduced in patients with life-threatening ventricular arrhythmias occurring long after MI. A persistent depression of vagal reflexes may play a role in the occurrence of malignant arrhythmias, and analysis of BRS may potentially be helpful in the identification of patients at high risk long after myocardial infarction.
UR - http://www.scopus.com/inward/record.url?scp=0029151375&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0029151375&partnerID=8YFLogxK
U2 - 10.1016/0002-8703(95)90354-2
DO - 10.1016/0002-8703(95)90354-2
M3 - Article
C2 - 7661063
AN - SCOPUS:0029151375
VL - 130
SP - 473
EP - 480
JO - American Heart Journal
JF - American Heart Journal
SN - 0002-8703
IS - 3 PART 1
ER -