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PubMed1993

Non-invasive evaluation of left ventricular systolic function late after coarctation repair: influence of early vs late surgery.

The study was designed to assess non-invasively the long-term effect of coarctation repair on systemic blood pressure, left ventricular (LV) muscle mass (LMM) and LV systolic function. Blood pressure and pressure gradients across the coarctation site were measured at rest and during exercise. LV systolic function and LMM were assessed by echocardiography. Twenty-eight patients late after successful coarctation repair were divided according to their age at surgery into two groups: group 1: < 1 year (10 days-12 months, mean 0.2 years) and group 2: > 1 year (1-19 years, mean 9.7 years). A group of age- and sex-matched patients with normal LV function served as controls. LMM was increased late postoperatively in both groups irrespective of the age at surgery and was correlated significantly with the elevated systolic blood pressure and the residual pressure gradient at exercise. End-systolic wall stress was normal at rest and the stress/velocity relationship revealed normal contractility in all patients. Despite successful operation of aortic coarctation, residual LV hypertrophy persists 2 to 19 years after surgery irrespective of the age at surgery. LV systolic function is normal. Hypertrophy can be explained by the residual arm-leg pressure gradient during exercise which persists even after successful repair.

Adolescent↗
PubMed2000

Age-related changes in pumping mechanical behavior of rat ventricle in terms of systolic elastance and resistance.

Both the maximal systolic elastance (Emax) and the theoretical maximal flow (Qmax) can quantify the systolic mechanical behavior of the ventricular pump. Physically, Emax can reflect the intrinsic contractility of the myocardium as an intact heart. The quantity in (Qmax is inversely related to the internal resistance of the left ventricle. How great the effects of age are on these Emax and Qmax has never been examined, however. This study was to determine the ventricular pumping mechanics in terms of the systolic elastance and resistance in male Fischer rats at 6, 12, 18, and 24 months of age. We measured left ventricular (LV) pressure and ascending aortic flow waves using a high-fidelity pressure sensor and an electromagnetic flow probe, respectively. Those two parameters that characterize the systolic pumping mechanics of the left ventricle are obtained by making use of an elastance-resistance model. The basic hemodynamic condition in those animals with different ages is characterized by (i) no significant change in cardiac output and (ii) a decrease in basal heart rate, LV end-systolic pressure, as well as effective arterial volume elastance. Changes that take place in the left ventricle with age include a decline in Emax and an increase in Qmax especially at 24 months. These results demonstrate that the impaired intrinsic contractility of an aging heart may be compensated to some extent by the diminished ventricular internal resistance. Such compensation in aging rats may maintain normal blood flow essential for the metabolic needs of tissues and/or organs before heart dysfunction and failure occur.

Aging↗
PubMed1991

Postural change in blood pressure associated with age and systolic blood pressure. The National Health and Nutrition Examination Survey II.

The prevalence of postural change in blood pressure and its association with age and systolic blood pressure were examined in data from 8,574 White nondiabetic persons aged 25-74 who participated in the second National Health and Nutrition Examination Survey (1976-1980). Postural change in blood pressure was defined as a drop of 20 mm Hg or more on change from supine to seated position. In subjects on no antihypertensive medications (n = 7,316), the prevalence of postural change in blood pressure increased with older age and with higher blood pressure levels, regardless of age. However, systolic blood pressure levels also increased with age. In logistic regression models, level of supine systolic blood pressure was strongly related to postural change in blood pressure (Relative odds (RO) = 1.59, 95% confidence interval (CI) = 1.49, 1.70 for a 10 mm Hg increase in systolic blood pressure) whereas age was not related to postural change in blood pressure (RO for age = 1.07, Cl = .89, 1.19 for a 10-year increase in age). Results were similar for those medicated for hypertension. All results were unchanged by addition of health status indicators, including reports of hospitalization and number of medical conditions, to the model. These data suggest that the age-related increase in the prevalence of postural hypotension previously reported may be partially explained by age-associated increases in systolic blood pressure.

Adult↗
PubMed1993

Modification of increasing systolic blood pressure in the elderly during the 1980s.

The authors examined whether changing attitudes and approaches to modifying blood pressure during the 1980s affected the previously described pattern of increasing systolic blood pressure in the elderly which continues through the ninth decade of life. In 1982-1983, a door-to-door census identified 4,497 community-dwelling residents of East Boston, Massachusetts aged 65 and over, of whom 3,657 had baseline blood pressure assessments. Follow-up blood pressure assessments occurred in 1985-1986 and in 1988-1989. Cross-sectionally, the relation of age with systolic blood pressure was quadratic with levels predicted to increase until about age 84 after which they were lower among oldest-old survivors. Longitudinally, mean age-sex-adjusted systolic blood pressure was 3.3 mmHg lower in 1985-1986 compared with 1982-1983 (95 percent confidence interval (CI) 2.4-4.2 mmHg) and 10.6 mmHg lower in 1988-1989 compared with 1982-1983 (95 percent CI 9.5-11.7 mmHg). Utilization of antihypertension medications increased over time and accounted for some, but not all, of the observed decreases in systolic blood pressure. Large shifts occurred in the use of specific antihypertension medications including increases in use of angiotensin converting enzyme inhibitors and calcium entry blockers and decreases in use of thiazide diuretics. Previously described trends for increasing systolic blood pressure in the elderly were reversed during the 1980s when the continued decline in cardiovascular mortality was greatest among the elderly.

Age Factors↗
PubMed1991

Systolic intra-cavitary gradients following aortic valve replacement: an echo-Doppler study.

Systolic left ventricular flow was studied by pulsed and continuous wave Doppler in 41 patients following aortic valve replacement for severe stenosis (mean valvular area: 0.58 cm2; range 0.3-0.75 cm2). Maximal left ventricular velocities by continuous wave Doppler study, were higher than 2.5 m.s-1 with a sharp peak at end-systole in five patients in basal condition and in four others after amyl nitrite inhalation. Pulsed Doppler study showed that the high velocities started from the apex or mitral papillary muscle level with a marked chamber narrowing at two-dimensional echography. Only one patient had a systolic anterior motion (SAM) of the anterior mitral leaflet with mitral-septal contact. The left ventricular dimensions, as measured by M-mode echography were compared in the various patient groups. High velocities seemed statistically associated with the smaller systolic and diastolic diameters of the left ventricle and outflow tract and the larger relative thickness of the posterior wall. The highest pressure gradients disappeared after correction of hypovolaemia (one patient), clearance of pericardial effusion (one patient), or beta-blocker treatment (three patients). The present study confirms that left intra-ventricular dynamic gradients can occur after clearance of fixed outflow obstruction, for which Doppler examination is a reliable and innocuous diagnostic means. Haemodynamically, this syndrome resembles hypertrophic obstructive cardiomyopathy, but the scarcity of the systolic anterior motion of the mitral leaflets is suggestive of a different mechanism that could be cavity obliteration or mid-ventricular obstruction.

Adult↗
PubMed1991

Non-invasive assessment of systolic left ventricular function in systemic sclerosis.

Systemic sclerosis is a multisystemic disorder, also affecting the heart. To evaluate its influence on systolic left ventricular (LV) function, we investigated 30 consecutive patients (age 54.5 +/- 2.4 years, 15 men and 15 women) and 48 controls matched for age and sex. All subjects were investigated by phonocardiography, pulse curve recordings, M-mode echocardiography, and by pulsed and continuous wave Doppler. Heart rate, blood pressure and peripheral resistance did not differ, but patients weighed less than controls (P less than 0.01). Systolic time intervals indicated systolic impairment, with an increased pre-ejection period to LV ejection time (LVET) ratio (0.37 +/- 0.02 vs 0.30 +/- 0.01 P less than 0.001), and also an increased isovolumic contraction time to LVET ratio (0.17 +/- 0.02 vs 0.12 +/- 0.01, P less than 0.02). The latter difference remained when LVET was adjusted for heart rate. Echocardiographic E-point to septal separation was increased in patients (8.3 +/- 1.3 vs 4.8 +/- 0.3 mm, P = 0.001), also after adjustment for LV dimension (P = 0.0001), while septal fractional thickening was decreased (P less than 0.01). End systolic wall stress (P = 0.0002) and stress to volume ratio (P = 0.03) were lower in systemic sclerosis. Peak LV emptying rate was also lower in the patient group when measured by echocardiography (P = 0.03). There was no difference between groups regarding LV dimensions, fractional shortening or mean velocity of circumferential fibre shortening. While aortic Doppler peak emptying rate did not differ between groups, it occurred later in systole in the patient group (P less than 0.01) as did peak velocity (P = 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Determination of left ventricular systolic wall thickness by digital subtraction angiography.

The accuracy of digital subtraction angiography (DSA) for determination of left ventricular (LV) systolic wall thickness and muscle mass was evaluated in 20 patients (mean age 50 +/- 11 years). Conventional LV angiograms were digitized and subtracted using a combined subtraction mode ('mask mode' and 'time interval difference' subtraction). Wall thickness and muscle mass were determined at end-diastole, after the first- and second-third of systole and at end-systole. M-mode echocardiography (Echo), which was obtained from beam selection of the two-dimensional echocardiogram and conventional angiography (LVA), served as reference techniques. Angiographic LV wall thickness and muscle mass were determined according to the technique of Rackley in both, right (RAO) and left (LAO) anterior oblique projections, whereas echocardiographic wall thickness was measured just below the mitral valve orthogonal to the posterior wall (= LAO equivalent). Percent wall thickening was calculated in all patients. LV end-diastolic wall thickness and muscle mass correlated well between DSA and LVA (LV end-diastolic wall thickness in LAO projection r = 0.72, biplane LV end-diastolic muscle mass r = 0.83), LV end-systolic wall thickness (1.44 vs 1.33 cm, P less than 0.05) and percent wall thickening (52 vs 42%, P less than 0.05) compared favourably between echocardiography and DSA but was significantly larger when echocardiographically measured than with DSA (LAO projection). DSA and echocardiography showed a good correlation in regard to LV end-diastolic and end-systolic wall thickness (correlation coefficient r = 0.89, standard error of estimate SEE = 0.15 cm or 13% of the mean value).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1996

Case report: reversible systolic heart failure and deep jaundice in hyperthyroidism.

Systolic heart failure because of hyperthyroidism in patients without preexisting heart disease is not common. Thyrotoxic systolic heart failure is rarely diagnosed during life. Reports about thyrotoxicosis-related systolic heart failure have been diagnosed postmortem. However, antemortem diagnosis of this fatal disease has important clinical implications because if detected early, thyrotoxicosis-related systolic heart failure is reversible. Here is a report a patient with Graves' disease, systolic heart failure, and deep jaundice, which resolved after the treatment of antithyroid drugs.

Female↗
PubMed1988

Left ventricular systolic function in relation to withdrawal of different pharmacological treatments in hypertensives with left ventricular hypertrophy.

We evaluated the left ventricular mass index (LVMI) and the functional response to cold pressor and handgrip tests in 74 untreated essential hypertensive patients and 26 age and sex-matched normals. The same measurements were repeated in 22 essential hypertensives after 6 and 12 months of treatment (captopril or nitrendipine, plus diuretic or beta-blocker in a few cases) and in 21 essential hypertensives after withdrawal of treatment, a reduction in the LVMI and a further increase in blood pressure. Left ventricular systolic function was evaluated by the relationship between left ventricular end-systolic stress and fractional shortening. Highly significant negative correlations, with similar slopes and intercepts, were found between end-systolic stress and fractional shortening under basal conditions, after regression of left ventricular hypertrophy and after withdrawal of treatment, both at rest and at the peak of stress tests. An examination of each point of the relation between end-systolic stress and fractional shortening showed that very few points were beyond the 95% prediction limits of the correlation obtained in normal volunteers. These results indicate that left ventricular systolic function is normal in most untreated essential hypertensives, and is usually well maintained after regression of left ventricular hypertrophy during long-term treatment as well as after withdrawal of treatment, both at rest and during an acutely induced afterload increase.

Adult↗
PubMed1997

Lacidipine, hydrochlorothiazide and their combination in systolic hypertension in the elderly.

OBJECTIVE: To compare with placebo the efficacies of once-daily administrations of lacidipine and hydrochlorothiazide separately and in combination to elderly patients with systolic hypertension. DESIGN AND METHODS: Nineteen elderly subjects (five men and 14 women, median age 71 years, range 62-79 years) participated in the study, which had a randomized double-blind crossover design. For each subject there were four treatment phases, each of duration 4 weeks. The initial treatments in each phase were 2 mg lacidipine once a day and 25 mg hydrochlorothiazide once a day, separately and in combination, and placebo. Doses of each agent could be doubled after 2 weeks in each phase if the patient's goal systolic blood pressure had not been achieved. The numbers of subjects administered the higher dose of each treatment were 13 for placebo, 14 for lacidipine, 11 for hydrochlorothiazide and eight for lacidipine plus hydrochlorothiazide. RESULTS: End-of-phase mean clinic blood pressures were 164/85 mmHg with placebo, 159/82 mmHg with lacidipine, 157/84 mmHg with hydrochlorothiazide and 152/82 mmHg with lacidipine plus hydrochlorothiazide. Systolic blood pressure was significantly reduced during all active treatment phases compared with placebo and that for the lacidipine plus hydrochlorothiazide phase was also significantly less than those for both of the other active treatment phases. There was no difference between sitting and standing blood pressure for any phase. Factorial analysis of the main effects of treatment indicated that the effects of lacidipine and hydrochlorothiazide on clinic blood pressure were additive and also that heart rate was higher when hydrochlorothiazide had been administered. Ambulatory blood pressure monitoring confirmed the pattern of the responses of blood pressure and showed that administration of hydrochlorothiazide had a significantly greater effect on systolic blood pressure and a longer duration of action than did administration of lacidipine. There was no difference in the frequency of adverse effects among any of the phases. CONCLUSIONS: In treating elderly systolic hypertensives the diuretic hydrochlorothiazide is a more effective antihypertensive agent with a longer duration of action than is the calcium channel antagonist lacidipine. In combination the effects of these two drugs on blood pressure are additive.

Aged↗
PubMed1998

Correlates of cognitive status of old patients with isolated systolic hypertension: the Syst-Eur Vascular Dementia Project.

OBJECTIVE: To assess cognitive functions and their correlates for a dementia-free cohort of old patients with isolated systolic hypertension. DESIGN: Cross-sectional data from the randomization period of the European Trial in Elderly with Systolic Hypertension (Syst-Eur Vascular Dementia Project). SETTING: Sixteen European countries and Israel. PARTICIPANTS: We studied 2252 patients aged 60-100 years (mean 70). MAIN OUTCOME MEASURES: Mini Mental State Examination (MMSE) and Spearman correlation of MMSE scores to demographic data or blood pressure. RESULTS: The MMSE was successfully completed for 1474 women and 751 men. The baseline blood pressure averaged 173 +/- 10/86 +/- 6 mmHg (means +/- SD). Median age at which education of patients at school had stopped was 15 years. Men and women who consumed alcohol (28%) had median intakes of 8 and 3 g/day, respectively. The median MMSE score was 29 (range 15-30). The maximum score of 30 was attained by 609 (30%) subjects. Fifty-nine (3%) patients had a MMSE score of 23 or less. The MMSE score decreased with advancing age (r = -0.21, P < 0.001). Both for men and for women, it was positively correlated to the level of education (r = 0.30 and r = 0.32, P < 0.001). For women after adjustment for age and the level of education, the score was correlated negatively to systolic blood pressure (r = -0.07, P < 0.05) but positively to intake of alcohol (r = 0.06, P < 0.05). CONCLUSION: In a cohort of elderly patients with isolated systolic hypertension, baseline cognitive function measured in terms of the MMSE score was high, probably due to selective recruitment of patients who were not clinically demented. Blood pressure was a weak contributor to cognitive status compared with age and level of education. Baseline cognitive function of women was negatively and independently correlated to systolic blood pressure.

Aged↗
PubMed1999

A controlled study of the effects of isosorbide mononitrate on arterial blood pressure and pulse wave form in systolic hypertension.

OBJECTIVE: To determine the effect of an extended-release nitrate preparation on the arterial pulse wave and blood pressure of patients in whom systolic blood pressure was elevated in part by exaggerated pulse-wave reflectance. DESIGN: A double-blind randomized placebo-controlled crossover study was carried out. PATIENTS AND METHODS: The subjects were ten elderly patients with systolic hypertension resistant to conventional anti-hypertensive therapy. Pharmacodynamic responses to 2-week courses of placebo/isosorbide mononitrate (ISMN) were assessed in seven subjects by an ambulatory blood pressure monitor, and in all ten subjects by standard sphygmomanometry, arterial pulse-wave analysis and measurement of plasma nitrate concentration during peak and trough. RESULTS: Ambulatory systolic blood pressure was decreased by ISMN (P < 0.02) between 1000 and 2200 h. Ambulatory diastolic blood pressure fell with ISMN (P < 0.01) during the last 4 h of this period. At peak plasma nitrate levels, ISMN decreased the aortic systolic blood pressure (P < 0.01), ejection peak (P < 0.02) and augmentation component (P < 0.001) of the pulse wave; heart rate increased slightly (P < 0.03). CONCLUSION: ISMN has a role as an adjunct in the anti-hypertensive therapy of patients with refractory systolic hypertension due to exaggerated pulse-wave reflectance.

Aged↗
PubMed1996

The value of Doppler resistive index and peak systolic velocity in the evaluation of porcine renal obstruction.

PURPOSE: We evaluated the use of Doppler resistive indexes and systolic velocities as diagnostic tools in a partially obstructed animal model. MATERIALS AND METHODS: We studied 12 normal pigs by Doppler sonography, which served as control units. In 9 subjects partial ureteral obstruction was then created surgically, and 3 continued as controls. The presence or absence of obstruction was confirmed by ultrasound, antegrade nephrostography and intrapelvic pressure monitoring. Doppler parameters were measured 1 hour to 21 days postoperatively. Resistive index, and angle corrected peak and mean systolic velocities were measured bilaterally from samplings of interlobar and arcuate arteries. An average of 4 samplings per kidney was obtained at each session. Data from the control and obstruction groups were compared for statistical differences. RESULTS: In controls mean resistive index was 0.53, and peak and mean systolic velocities were 0.38 and 0.26 m. per second, respectively. In the subacute period after obstruction (defined as days 4 to 21) mean resistive index was 0.54, and peak and mean systolic velocities were 0.33 and 0.22 m. per second, respectively. Compared to control data there was no significant change in resistive index after obstruction (p = 0.6). However, peak and mean systolic velocities showed significant downward trends (p < 0.05). CONCLUSIONS: Known small sequential changes in renal blood flow after ureteral obstruction are reflected in flow velocities, as measured by duplex Doppler sonography. However, resistive indexes are not useful in assessing these changes in renal blood flow, and they do not correlate with the presence or absence of obstruction in this animal model.

Animals↗
PubMed1999

Systolic and diastolic cardiac function time intervals and exercise capacity in women.

PURPOSE: To determine the relationship between exercise capacity and resting cardiac function time intervals in women. METHODS: The noninvasive method of seismocardiography was used to measure resting cardiac intervals in 12 female subjects. On the basis of maximal treadmill time (Bruce protocol), two groups were studied and categorized as long duration runners (LDR; N = 6) or short duration runners (SDR, N = 6). The following resting atrial and left ventricular (LV) cardiac function time intervals were determined: atrial systole, LV systole, LV diastole, LV isovolumetric contraction, LV isovolumetric relaxation, LV ejection, LV preejection, LV filling, LV rapid filling, and Tei index. RESULTS: Heart rate (HR) (65+/-3 vs 61+/-4 b x min(-1) for LDR and SDR, respectively; P = NS) and atrial systolic time (75+/-6 vs 81+/-5 ms for LDR and SDR, respectively; P = NS) were similar between groups. LV systole (348+/-15 vs 302+/-8 ms for LDR and SDR, respectively; P < 0.05) and LV ejection (297+/-13 vs 247+/-7 ms for LDR and SDR, respectively; P < 0.01) were longer in LDR, despite a similar LV isovolumetric contraction time. There was a general trend for a shortened LV diastole in LDR with a significantly shortened LV isovolumetric time in LDR (80+/-8 vs 107+/-8 ms for LDR and SDR, respectively; P < 0.05). LV preejection was shorter in LDR versus SDR (LDR; 114+/-6 vs SDR; 130+/-3 ms, P < 0.05), and the Tei index was less in LDR versus SDR. CONCLUSIONS: Independent of HR, increased treadmill time in young women is associated with greater resting systolic time intervals and decreased diastolic cardiac function time intervals.

Adult↗
PubMed1998

Problems with use of the end systolic pressure-volume slope as an indicator of left ventricular contractility: an alternate method.

The use of end-systolic elastance as a parameter of left ventricular contractility is based on a theory put forward by Sagawa and is limited by an assumed linearity of the model for a time varying compliance. A major problem is the contractility-dependent curvilinearity of the end-systolic pressure-volume relationship (ESPVR), which may result in intercept volumes that are below a passive unstretched volume. Based on the experimental data of Burkhoff et al., we demonstrate the reasons for the lack of correlation of the slope (k) of the end-systolic pressure (P(es))-volume (V(es)) relationship with ventricular contractility. A parabolic relation, P(es) = a x V(es)2 + b x V(es) + c, was used for approximation of the ESPVRs, as proposed by Burkhoff et al., and the slope (k = 2 x a x V(es) + b), together with the volume axis intercepts (V0), calculated for the tangents for all P(es)/V(es) points of the ESPVRs. The results demonstrate the volume range dependence of the slope and V0 of linear regression lines. However, intercepts of the ESPVRs tangents with a midrange constant pressure line (e.g., 80 mmHg or 100 mmHg) justify the use of the shift of the end-systolic pressure-volume relationship as a parameter of left ventricular contractility. This method appears to be valid over a much wider range of end-systolic volumes than is the use of the slope alone.

Animals↗
PubMedDate not supplied

Epidemiology, pathophysiology, prognosis, and treatment of systolic and diastolic heart failure.

Underlying causes, risk factors, and precipitating causes of heart failure (HF) should be treated. Drugs known to precipitate or aggravate HF such as nonsteroidal antiinflammatory drugs should be stopped. Patients with HF and a low left ventricular ejection fraction (systolic heart failure) or normal ejection fraction (diastolic HF) should be treated with diuretics if fluid retention is present, with an angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker if the patient cannot tolerate an ACE inhibitor because of cough, angioneurotic edema, rash, or altered taste sensation, and with a beta blocker unless contraindicated. If severe systolic HF persists, an aldosterone antagonist should be added. If HF persists, isosorbide dinitrate plus hydralazine should be added. Calcium channel blockers should be avoided if systolic HF is present. Digoxin should be avoided in men and women with diastolic HF if sinus rhythm is present and in women with systolic HF. Digoxin should be given to men with systolic HF if symptoms persist, but the serum digoxin level should be maintained between 0.5 and 0.8 ng/mL.

Cardiovascular Agents↗
PubMed2006

Profound impact of uncomplicated pregnancy on diastolic, but not systolic pulse contour of aortic pressure.

OBJECTIVE: To evaluate the impact of uncomplicated pregnancy on the pulse contour of central aortic pressure. METHODS: A total of 66 women with singleton pregnancy were grouped according to pregnancy duration: first trimester (T1, n = 22), second trimester (T2, n = 20), and third trimester (T3, n = 24). Non-pregnant healthy women, who took combined oral contraception, were included as controls (C, n = 21). The pulse contour of aortic pressure was obtained with radial applanation tonometry, using a commercial device (SphygmoCor). The influence of reflected waves on the contour was evaluated not only in systole, as usual with pulse contour analysis (systolic augmentation), but also in diastole (diastolic augmentation). RESULTS: Throughout pregnancy, central systolic and diastolic blood pressure remained unchanged and comparable to values in the non-pregnant state. Systolic augmentation amounted to 8.1 +/- 7.5% of pulse pressure in the control group (mean +/- SD), and there was no statistically significant deviation from this value at any stage of pregnancy (T1, 4.6 +/- 11.4%; T2, 5.0 +/- 9.3%; T3, 4.7 +/- 8.1%). In contrast, the amplitude of the diastolic augmentation wave progressively declined with advancing pregnancy (C, 6.5 +/- 2.4%; T1, 5.2 +/- 3.1%; T2, 3.8 +/- 2.6%; P = 0.002 versus C, T3, 2.3 +/- 2.0%; P < 0.0001 versus C and P = 0.0004 versus T1). CONCLUSION: The systolic shape of the central aortic pressure contour is left unaltered by pregnancy, implying a finely tuned adaptation of the cardiovascular system to the increased demand for blood flow at all stages of the gravid state. In contrast, the amplitude of reflection waves reaching the aortic root in diastole progressively decreases with advancing pregnancy.

Adult↗
PubMed2006

Left ventricular diastolic filling characteristics are not impaired but systolic performance was augmented in the early hours of experimental endotoxemia in humans.

This study was performed to determine whether endotoxemia causes diastolic cardiac dysfunction. Eleven healthy volunteers, 30 +/- 6 years of age, underwent comprehensive transthoracic echocardiographic assessment including two-dimensional, M-mode transmitral and tissue Doppler of systolic and diastolic function at baseline and at 3 and 5 h after intravenous administration of purified Escherichia coli endotoxin (4 ng/kg). Data were analyzed by analysis of variance; P values of less than 0.05 were considered significant. Endotoxin administration resulted in a hyperdynamic state characterized by decreased mean arterial pressure and significant increase in cardiac index. This was accompanied by increases in several load-dependent systolic performance indices (3 and 5 h). Robust increases in peak systolic blood pressure/end-systolic volume index, one of the relatively load-independent contractility parameter, were also observed at 3 h after endotoxin administration. Transmitral peak early velocity (E), which represents early filling, significantly increased at 3 h after infusion. Late diastolic velocity (A), which represents atrial contraction, significantly increased at 3 and 5 h after infusion. The E/A ratio indicative of delayed relaxation significantly decreased due to increases in A (transmitral) and A (tissue Doppler) at 3 and 5 h after infusion. As expected, endotoxin infusion resulted in a hyperdynamic state associated with increases in systolic function indices including endocardial systolic velocities. The observed decreases in E/A (transmitral) and E/A (tissue Doppler) ratio were primarily due to increases in A and A. Moreover, isovolumic relaxation time and time constant for left ventricular relaxation, a load-independent parameter for ventricular relaxation, remained unchanged at 3 and 5 h after endotoxin infusion. Therefore, our findings are more likely due to enhanced atrial contractility resulting from increased sympathetic activity in response to reduction in left ventricular afterload and not due to altered diastolic filling characteristics.

Adult↗