Related Experiment Videos
Study of late potentials and ventricular arrhythmias in hypertensive patients with normal electrocardiograms
P E Vardas1, E N Simandirakis, F I Parthenakis
1Cardiology Department, University of Crete, University Hospital, Heraklio, Greece.
Insights
Hypertensive patients without ECG-indicated hypertrophy show a high prevalence of ventricular arrhythmias. This arrhythmia risk is linked to ventricular late potentials, not left ventricular hypertrophy.
Area of Science:
- Cardiology
- Electrophysiology
- Hypertension Research
Background:
- Hypertension is associated with increased ventricular arrhythmias.
- The prevalence and pathophysiology of these arrhythmias in hypertensive patients without ECG signs of hypertrophy require further investigation.
Purpose of the Study:
- To determine the incidence and severity of ventricular arrhythmias in hypertensive patients lacking electrocardiographic evidence of hypertrophy.
- To explore the relationship between ventricular late potentials, hypertrophy, and ventricular arrhythmias in this patient group.
Main Methods:
- Seventy-eight hypertensive patients with normal ECGs underwent echocardiography, 24-hour ambulatory monitoring, exercise testing, and signal-averaged electrocardiography.
- Signal-averaged electrocardiograms were analyzed using a 40- to 250-Hz filter with a noise level below 0.3 microV.
Main Results:
- Twenty-seven percent of patients exhibited severe ventricular arrhythmias.
- Left ventricular hypertrophy was present in 74.3% of patients, but severe arrhythmias were not significantly correlated with hypertrophy.
- Ventricular late potentials were identified in 24.5% of patients and were significantly associated with severe ventricular arrhythmias (57.89% vs. 16.94%).
Conclusions:
- In hypertensive individuals without ECG-defined hypertrophy, ventricular arrhythmias are prevalent.
- The increased risk of ventricular arrhythmias is associated with the presence of ventricular late potentials, rather than left ventricular hypertrophy.
Introduction:
Although an increase in the occurrence of ventricular arrhythmias has been observed in hypertensive patients, some basic questions remain unresolved regarding the prevalence and the pathophysiology of these arrhythmias. The basic aims of this study were as follows: (1) to examine the incidence and severity of ventricular arrhythmias in a substantial number of hypertensive patients without electrocardiographic indications of hypertrophy; and (2) to examine the correlation between late potentials, hypertrophy, and ventricular arrhythmias in these patients.
Materials And Methods:
We studied 78 consecutive patients (31 men, 47 women), aged 60.5 +/- 7.8 years, with a history of hypertension but a normal electrocardiogram. All patients had an echocardiographic study, 24-hour ambulatory monitoring, exercise test, and signal-averaged electrocardiogram. The latter was analyzed using a 40- to 250-Hz filter and with a noise level < or = 0.3 microV.
Results:
Of the 78 patients studied, 21 (26.9%) had severe ventricular arrhythmias, while 57 (73.1%) had either no ventricular ectopics or sporadic isolated ventricular extrasystoles. Left ventricular hypertrophy, defined by echocardiography, was found in 58 patients (74.3%), of which 16 (27.58%) had severe ventricular arrhythmias. Five (25%) of the 20 patients without hypertrophy also had severe ventricular arrhythmias (P = NS). Ventricular late potentials were recorded in 19 (24.5%) of the 78 patients. Of these, 11 (57.89%) had severe arrhythmias, while of the 59 patients without late potentials 10 (16.94%) had severe ventricular ectopic activity.
Conclusions:
In hypertensive patients without electrocardiographic signs of hypertrophy, the higher prevalence of ventricular arrhythmias does not appear to be related to left ventricular hypertrophy but is correlated with the existence of ventricular late potentials.