TY - JOUR
T1 - Markers of electrical instability in hypertensive patients with and without ventricular arrhythmias. Are they useful in identifying patients with different risk profiles?
AU - Facchini, Mario
AU - Malfatto, Gabriella
AU - Ciambellotti, Francesca
AU - Riva, Beatrice
AU - Bragato, Renato
AU - Branzi, Giovanna
AU - Leonetti, Gastone
PY - 2000
Y1 - 2000
N2 - Background. Markers of electrical instability of the ventricular myocardium, namely abnormal repolarization and late potentials, are frequently observed in patients with hypertension when both ventricular arrhythmias and left ventricular hypertrophy are present. This information cannot be extrapolated to the population of hypertensive patients with ventricular arrhythmias but without left ventricular hypertrophy. Objective. To evaluate QT duration, QT dispersion and the incidence of ventricular late potentials in patients with essential hypertension, already on anti-hypertensive therapy, both with and without non-sustained ventricular arrhythmia. Design. The study population consisted of 49 patients with essential hypertension who were compared to 89 control normotensive subjects both with and without frequent (> 30 per h) ventricular ectopic beats (VPBs). Patients were divided into four groups: (1) hypertensive patients without VPBs (H, n = 19), (2) hypertensive patients with VPBs (HA, n = 30), (3) normotensive subjects without VPBs (C, n = 28), and (4) normotensive subjects with VPBs (CA, n = 61). Methods. Echocardiographic parameters, QT interval, QT dispersion and signal-averaged ECG were evaluated without withdrawing anti-hypertensive drugs. Results. In no case was left ventricular hypertrophy documented. The number of VPBs during 24 h Holter recording (median 11,343 versus 7617) and the incidence of repetitive VPBs (37 versus 46% of patients) were similar in the two groups of patients (HA versus CA). Signal-averaged ECG parameters were normal and not different between the four groups. QT interval was longer in hypertensive patients compared to controls irrespective of the presence of VPBs. QT dispersion was slightly greater in subjects with VPBs, both hypertensive and normotensive, compared to subjects without arrhythmias. Conclusions. In patients with hypertension well-controlled by drug therapy and without left ventricular hypertrophy, frequent VPBs are not associated with markers indicating an electrophysiological substrate for re-entrant arrhythmias. However, QT prolongation suggests the persistence of a higher risk of cardiovascular mortality that is independent of the presence of VPBs. (C) Lippincott Williams and Wilkins.
AB - Background. Markers of electrical instability of the ventricular myocardium, namely abnormal repolarization and late potentials, are frequently observed in patients with hypertension when both ventricular arrhythmias and left ventricular hypertrophy are present. This information cannot be extrapolated to the population of hypertensive patients with ventricular arrhythmias but without left ventricular hypertrophy. Objective. To evaluate QT duration, QT dispersion and the incidence of ventricular late potentials in patients with essential hypertension, already on anti-hypertensive therapy, both with and without non-sustained ventricular arrhythmia. Design. The study population consisted of 49 patients with essential hypertension who were compared to 89 control normotensive subjects both with and without frequent (> 30 per h) ventricular ectopic beats (VPBs). Patients were divided into four groups: (1) hypertensive patients without VPBs (H, n = 19), (2) hypertensive patients with VPBs (HA, n = 30), (3) normotensive subjects without VPBs (C, n = 28), and (4) normotensive subjects with VPBs (CA, n = 61). Methods. Echocardiographic parameters, QT interval, QT dispersion and signal-averaged ECG were evaluated without withdrawing anti-hypertensive drugs. Results. In no case was left ventricular hypertrophy documented. The number of VPBs during 24 h Holter recording (median 11,343 versus 7617) and the incidence of repetitive VPBs (37 versus 46% of patients) were similar in the two groups of patients (HA versus CA). Signal-averaged ECG parameters were normal and not different between the four groups. QT interval was longer in hypertensive patients compared to controls irrespective of the presence of VPBs. QT dispersion was slightly greater in subjects with VPBs, both hypertensive and normotensive, compared to subjects without arrhythmias. Conclusions. In patients with hypertension well-controlled by drug therapy and without left ventricular hypertrophy, frequent VPBs are not associated with markers indicating an electrophysiological substrate for re-entrant arrhythmias. However, QT prolongation suggests the persistence of a higher risk of cardiovascular mortality that is independent of the presence of VPBs. (C) Lippincott Williams and Wilkins.
KW - Hypertension
KW - Late potentials
KW - QT dispersion
KW - QT interval
KW - Signal-averaged ECG
KW - Ventricular arrhythmias
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M3 - Article
C2 - 10872562
AN - SCOPUS:0034130757
VL - 18
SP - 763
EP - 768
JO - Journal of Hypertension
JF - Journal of Hypertension
SN - 0263-6352
IS - 6
ER -