Left ventricular filling pressure, relaxation and chamber stiffness influence independently the pulsed Doppler mitral inflow pattern. The aim of this study was to analyze whether the characteristics of eccentric hypertrophy in hypertensive (Group HDC, 6 patients) as opposed to ischemic or idiopathic (Group IIDC, 14 patients) dilated cardiomyopathies may also influence the Doppler velocity profile. In both groups we investigated left ventricular systolic function, anatomy and the relative wall thickness/radius ratio (h/r) with two-dimensional and M-mode echocardiography, mitral inflow with pulsed Doppler, and determined hemodynamically brachial arterial and mean pulmonary wedge pressures at baseline and 40 min after left ventricular preload reduction with captopril 25 mg sublingual. Baseline mean arterial pressure (Group HDC = 137 ± 20 mmHg, Group IIDC = 95 ± 19; p <0.001), and h/r (Group HDC = 0.38 ± 0.03, Group IIDC = 0.28 ± 0.09; p <0.05) were greater in hypertensives, but mean wedge pressure (Group HDC = 27.7 ± 3 mmHg, Group IIDC = 20 ± 12; NS), left ventricular end-systolic wall stress (Group HDC = 202 ± 21 103 dynes/cm2, Group IIDC = 178 ± 100; NS), biplane ejection fraction, and the pulsed Doppler mitral inflow pattern were not significantly different in the two groups. After captopril, mean arterial pressure decreased significantly only in hypertensive patients (Group HDC, baseline = 137 ± 20, captopril = 120 ± 10, p <0.05; Group IIDC, baseline = 95 ± 19, captopril = 90 ± 24, NS), whereas wedge pressure was reduced to the same extent in both groups (Group HDC, baseline = 27.7 ± 2.5, captopril = 21 ± 7, p <0.05; Group IIDC, baseline = 20 ± 12, captopril = 15 ± 8, p <0.05); left ventricular wall stress and ejection fraction did not change significantly. Percent modifications of early and late diastolic mitral flow volumes after captopril differed between groups: early flow increased in Group HDC [(E wave integral) x (mitral annulus area)] (Group HDC = +38 ± 15%, Group IIDC = -1.3 ± 30; p <0.01), and late flow increased in Group IIDC [(A wave integral) x (mitral annulus area)] (Group HDC = +0.4 ± 40%, Group IIDC = +38 ± 19; p <0.01). Percentual variations of Doppler early/late flow volume ratio after captopril correlated with baseline h/r in both groups (r = 0.6, p <0.05). In dilated cardiomyopathy, Doppler left ventricular filling pattern changes following prevalent preload manipulation with captopril are related to h/r. In Group HDC, a higher h/r is associated with a 'true normalization' of the filling pattern following acute decrease in filling pressure, whereas in Group IIDC a lower h/r is associated with a 'pseudo-normalization' of the pattern in the same setting. It follows that the increased h/r found in hypertensive dilated cardiomyopathy is associated with a lesser impairment of baseline left ventricular diastolic function with respect to idiopathic or ischemic dilated cardiomyopathies.
|Translated title of the contribution||Influence of left ventricular relative wall thickness on the Doppler diastolic mitral filling pattern in hypertensive dilated cardiomyopathy: Evaluation through load reduction with captopril|
|Number of pages||8|
|Publication status||Published - 1993|
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Radiology Nuclear Medicine and imaging