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[Paradoxic changes in the morphology of blood pressure wave in hypertensive heart diseases]
M Chevallier1, J P Siche, F Tremel
1Service de médecine interne et cardiologie, CHU, Grenoble.
Insights
The study found that proximal aortic pressure waveform analysis cannot predict left ventricular mass index in hypertensive patients. Reduced left ventricular function impacts blood pressure waveform, decreasing amplification and pressure rise rate.
Area of Science:
- Cardiovascular Physiology
- Hypertension Research
- Biomedical Engineering
Background:
- Hypertension is associated with changes in left ventricular (LV) structure and arterial properties.
- Understanding the relationship between LV function and arterial compliance is crucial for managing cardiovascular risk.
Purpose of the Study:
- To investigate the correlation between left ventricular (LV) effects (LV mass index and inotropic state) and arterial compliance.
- To determine if proximal aortic pressure waveform and carotid-femoral pulse wave velocity can predict these relationships.
Main Methods:
- Applanation tonometry of the carotid artery to analyze proximal aortic pressure waveform, deriving index of amplification (AI) and other parameters.
- Echocardiography to assess LV mass index (LVMI), end systolic volume (ESV), and inotropic state.
- Carotid-femoral pulse wave velocity (PWV) measurement using mechanogram.
Main Results:
- No significant relationship was found between LVMI and AI in stepwise regression analysis, even after accounting for blood pressure, age, and height.
- In subjects with left ventricular hypertrophy (LVH), a bimodal distribution of AI was observed, suggesting distinct arterial responses.
- Type B classification showed weaker AI, reduced aortic rigidity, increased end systolic stress (ESS), and paradoxical fall in LV performance.
Conclusions:
- Proximal aortic pressure waveform analysis is insufficient for predicting LV mass index.
- Reduced LV function appears to contribute to modifications in the blood pressure waveform, characterized by diminished dp/dt and index of amplification.
Unlabelled:
The objective is to study the relation between left ventricular (LV) effect (index of LV mass (LVMI) and index of inotropic state) and arterial compliance determined but the proximal aortic pressure waveform and by the carotid femoral pulse wave velocity.
Material:
72 untreated hypertensives; systolic blood pressure (SBP) 170 +/- 18 mmHg/diastolic blood pressure (DBP); heart rate: 69 +/- 9 batt/min; age: 48 +/- 13 years; duration of hypertension 4.6 +/- 4.8 years; sex ratio 49 M/23 F.
Objective:
Proximal aortic pressure waveform (carotid artery) was studied by applanation tonometry. We derived the index of amplification (AI = Pmax-Pinflex)/PP, %), pulse pressure (PP), the maximum rate of rise of pressure (dpdt, mmHg.s-1). Echocardiography was used to define the index of LV mass (VLMI), end systolic volume (ESV), end systolic stress (ESS), myocardial contractile force (ESS/ESV), inotropic state (SBP/ESV). Carotid-femoral pulse wave velocity was determined by mechanogram (PWW m/s).
Results:
1. Relationship of physiological changes of AI and SDA to age, height, PP, DBP, PWV, and LVMI were observed in table I (r-Pearson cor. coefficient, * < p 0.05; **: p < 0.001). [table: see text] In stepwise regression analysis, even allowing for BP, age, and height, there was no relationship between LVMI and the index of aortic amplification (AI). 2. In the subjects with LVH (LVMI > 110 g/m2) we found a bimodal distribution of the AI which defines two groups in agreement with the Murgo Classification. [table: see text] In type B, where AI is weaker, the indices of aortic rigidity are reduced, there is an increased ESS and a paradoxal fall in LV performances.
Conclusion:
Analysis of proximal aortic pressure waveform don't allow to predict index of LV mass. These results suggest that in the sphere of LV aortic compiling the reduction of LV function contributes to modification of the BP waveform with diminution of dpdt and the index of amplification.