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Diastolic properties of hypertrophied hearts in essential hypertension: classification by left ventricular wall
K Iida1, Y Sugishita, K Yukisada
1Department of Internal Medicine, University of Tsukuba, Ibaraki.
Insights
Hypertensive cardiac hypertrophy (HH) patients were classified into inappropriate (HH-I) and appropriate (HH-II) types. HH-I showed supernormal systolic and normal diastolic velocity, while HH-II exhibited diminished diastolic velocity during isoproterenol infusion.
Area of Science:
- Cardiology
- Physiology
Background:
- Hypertensive cardiac hypertrophy is a common complication of hypertension.
- Classifying hypertrophy based on end-systolic wall stress can reveal distinct functional characteristics.
Purpose of the Study:
- To investigate the systolic and diastolic performance differences in patients with inappropriate (HH-I) and appropriate (HH-II) hypertensive cardiac hypertrophy compared to normal controls (NC).
- To assess these differences before and during isoproterenol infusion.
Main Methods:
- Echocardiography was used to measure end-systolic wall stress and classify 20 hypertensive patients into HH-I (n=8, subnormal stress) and HH-II (n=12, normal stress).
- Systolic and diastolic left ventricular performance was evaluated in HH-I, HH-II, and 10 NC subjects, both at rest and during isoproterenol infusion.
Main Results:
- Before isoproterenol, HH-I demonstrated significantly greater normalized peak systolic diameter change rate than NC and HH-II.
- During isoproterenol, HH-I maintained supernormal systolic velocity, while HH-II showed significantly diminished diastolic velocity compared to HH-I and NC.
- HH-I exhibited normal diastolic velocity before and during infusion, whereas HH-II showed diminished diastolic velocity during infusion.
Conclusions:
- Hypertensive patients with inappropriate hypertrophy display supernormal systolic and normal diastolic velocity.
- Hypertensive patients with appropriate hypertrophy exhibit diminished diastolic velocity, particularly during isoproterenol infusion.
- These findings highlight distinct functional profiles of different hypertensive cardiac hypertrophy types.
Abstract:
Hypertensive cardiac hypertrophy of 20 patients was classified as inappropriate hypertrophy (HH-I) and appropriate hypertrophy (HH-II) according to their end-systolic wall stress, as measured by echocardiography. The differences in systolic and diastolic performances among the HH-I and HH-II subjects and 10 normal controls (NC) before and during isoproterenol infusion were investigated. Eight patients had subnormal end-systolic wall stress (inappropriate hypertrophy) and 12, normal end-systolic wall stress (appropriate hypertrophy). Before isoproterenol infusion, normalized peak rate of a change in left ventricular diameter during systole was significantly greater in HH-I (3.5 +/- 0.8/s) than in NC (2.3 +/- 0.5/s) and HH-II (2.6 +/- 0.6/s) (p less than 0.01 and p less than 0.005), but there was no significant difference between HH-II and NC. There was no significant difference in normalized peak rate of a change of left ventricular diameter during the rapid filling phase among the three groups (4.5 +/- 1.2/s in HH-I, 4.0 +/- 1.6/s in HH-II, and 4.2 +/- 0.8/s in NC). During isoproterenol infusion, normalized peak rate of a change of left ventricular diameter during systole was significantly greater in HH-I (7.0 +/- 1.9/s) than in HH-II (4.8 +/- 1.7/s) and NC (4.8 +/- 0.8/s) (p less than 0.05 and p less than 0.01, respectively), but there was no significant difference between HH-II and NC. Normalized peak rate of a change of left ventricular diameter during rapid filling was significantly less in HH-II (4.8 +/- 1.7/s) than in HH-I (7.3 +/- 1.3/s) and NC (6.5 +/- 0.8/s) (p less than 0.005 and p less than 0.005, respectively), but there was no significant difference between HH-I and NC. These results suggest that hypertensive patients with inappropriate hypertrophy have relatively diminished diastolic velocity (supernormal systolic velocity and normal diastolic velocity) before and during isoproterenol infusion, and that hypertensive patients with appropriate hypertrophy have absolutely diminished diastolic velocity during isoproterenol infusion, in spite of normal diastolic velocity before the infusion.