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PubMed1990

Influence of coronary occlusion during PTCA on end-systolic and end-diastolic pressure-volume relations in humans.

The influence of acute coronary occlusion on systolic and diastolic left ventricular pressure-volume relations was studied in 10 patients undergoing percutaneous transluminal coronary angioplasty (PTCA). Pressure-volume relations were obtained by conductance catheter and micromanometer techniques and with volume load altered by transient inferior vena caval occlusion. End-systolic and end-diastolic pressure-volume relations were obtained at baseline, during 60-90 seconds of ischemia, and at return to baseline after angioplasty balloon deflation. Coronary occlusion significantly altered systolic and diastolic chamber function. Systolic dysfunction was characterized by a reproducible rightward shift of the end-systolic pressure-volume relation (+25.4 +/- 18.4 ml) that was greater for proximal left anterior descending and circumflex coronary artery occlusions (+41 ml) than for distal or right coronary artery occlusions (+15.4 ml, p less than 0.05). Occlusion also lowered chamber systolic function indexes, such as the end-systolic pressure-volume relation slope (from 4.2 to 2.8 mm Hg/ml) and preload recruitable stroke work (from 97 to 78.6 mm Hg). All systolic (and diastolic) changes were resolved with successful angioplasty. Diastolic abnormalities during angioplasty were characterized by prolonged pressure relaxation and an upward shift of the resting diastolic pressure-volume data and by an apparent increase in chamber elastic stiffness. However, when end-diastolic data from multiple beats during inferior vena caval occlusion were compared, control and ischemic end-diastolic pressure-volume relations displayed little or no difference. Thus, elevations in resting diastolic pressure-volume relations and apparent increase in chamber elastic stiffness during coronary occlusion in humans appear dominated by altered right ventricular or pericardial loading. These data indicate that pressure-volume analysis is useful in assessing the functional significance of coronary lesions and reperfusion.

Angioplasty, Balloon, Coronary↗
PubMed2005

Correlates of systolic hypertension in patients with chronic kidney disease.

Hypertension in patients with chronic kidney disease (CKD) is predominantly systolic. The contribution of risk factors for hypertension to the overall systolic blood pressure (BP) is unknown. To study the relationship between risk factors for hypertension and systolic BP in patients with CKD, 232 veterans (mean age 67 years; 96% men; 20% black; 39% with diabetes mellitus; estimated glomerular filtration rate [GFR] 48 mL/min per 1.73 m2) had clinic (routine and standardized measurements) and out-of-clinic (home and 24-hour ambulatory) BPs recorded. In multivariate analysis, using 17 risk factors, the log of the urine protein/creatinine ratio was the strongest predictor of systolic BP regardless of the BP measurement technique. The strength of the relationship between proteinuria and systolic BP was in the order ambulatory > home > standardized clinic > routine clinic BP measurement. Other independent predictors were age, race, and number of antihypertensive drugs used, and the model fit was better for out-of-clinic than clinic BP recordings. Estimated GFR was not an independent predictor of systolic BP by any technique. Nocturnal dipping was associated with higher estimated GFR, higher serum albumin, younger age, and less proteinuria. Proteinuria is the most important correlate of systolic BP in older men, the strongest relationship of which was with ambulatory and home systolic BP. Out-of-clinic BP recordings correlate better with target organ damage, as measured by proteinuria, and may be of greater clinical value than clinic BP recordings in predicting hypertension-related outcomes such as end-stage renal disease and death.

Aged↗
PubMed1990

Arterial stiffness, systolic blood pressure, and logical treatment of arterial hypertension.

Arterial stiffening is the principal cause of increasing systolic pressure with advancing years and in patients with arterial hypertension. It is associated with progressive arterial dilation and is due to degeneration of the arterial wall, probably as a consequence of repetitive cyclic stress; it increases systolic pressure directly by increasing amplitude of the pressure wave generated by a given flow impulse from the heart and indirectly by increasing wave velocity so that wave reflection from the periphery occurs earlier, augmenting pressure in late systole. The first mechanism affects pressure in both the central and peripheral arteries, the second predominantly in the central arteries. Change in brachial systolic pressure with age underestimates the rise in systolic pressure in the aorta and left ventricle. Arterial stiffness is reduced passively with reduction in arterial pressure. Drugs have little or no direct effect on arterial stiffness but can markedly reduce wave reflection. In patients with stiffened arteries, reduction in wave reflection decreases aortic systolic pressure augmentation. The decreased systolic pressure in central arteries brought about by this mechanism is not detected when systolic pressure is measured in a peripheral (brachial or radial) artery but can be inferred from change in contour of the pressure wave recorded in peripheral arteries.

Aging↗
PubMed2003

Anaesthesia and isolated systolic hypertension--pathophysiology and anaesthesia risk.

This review examines the pathophysiology of isolated systolic hypertension, changing medical perspectives on this condition as a cardiovascular risk factor in the community and evolving evidence of it being an independent risk factor for perioperative morbidity and mortality. Hypertension is regarded as an added risk in anaesthesia. Continuation of antihypertensive medication through the perioperative period is an established principle. Studies supporting this practice have demonstrated greater perioperative haemodynamic stability in association with general anaesthesia and surgery in patients with treated hypertension compared to untreated hypertension. Therapy has historically focused on control of diastolic blood pressure, rather than systolic blood pressure. Recent clinical trial data and data from large observational studies show a closer association of systolic hypertension with both coronary heart disease and stroke compared with diastolic hypertension. This has led to recommendations for aggressive treatment of isolated systolic hypertension, especially in patients over 65 years old. The association between decreased compliance of the central systemic arteries and isolated systolic hypertension is well understood. The fact that this same pathology, lack of compliance of central arteries, can cause a decrease in diastolic blood pressure is not so well recognised. This means that, in patients with isolated systolic hypertension, decreasing diastolic blood pressure can be associated with worsening arterial disease and that systolic minus diastolic blood pressure may give a better indication of the problem. Anaesthetic assessment and technique should be studied and potentially revised in the light of these changes in perspective on isolated systolic hypertension.

Adult↗
PubMed2000

Isolated Systolic Hypertension Is a Strong Predictor of Cardiovascular and All-Cause Mortality in the Middle-Aged Population: Warsaw Pol-MONICA Follow up Project.

OBJECTIVE: To assess the long-term risk of cardiovascular disease and all-cause mortality associated with various categories of hypertension, particularly isolated systolic hypertension. MATERIALS AND METHODS: Three independent random samples of the general Warsaw population aged 35-64 years (2490 men and 2405 women screened in 1984, 1988, and 1993) were followed for (1) cardiovascular death until 1996 and (2) all-cause death until 1998. Methods of the baseline surveys were consistent with the manual of the WHO MONICA Project. Isolated systolic hypertension was defined as systolic blood pressure greater than or equal to 140 mm Hg and diastolic blood pressure less than 90 mm Hg and was classified into two stages: stage I, when 90 is less than systolic blood pressure is less than 160 mm Hg; and stage II, for subjects with systolic blood pressure greater than or equal to 160 mm Hg. The Cox proportional hazard model was used to calculate the multivariable-adjusted relative risk of cardiovascular disease and all-cause mortality attributed to the particular hypertension category. RESULTS: Compared to normotension, stage I was associated with a 53%-60% increase in age-standardized cardiovascular mortality rates in both genders and with a 70% increase in all-cause mortality in men. A significant and independent association (after multivariable adjustment) was found only for all-cause mortality in men. Stage II was an independent predictor of cardiovascular mortality in men and in women, and of all-cause mortality in men. In both genders, the risks of examined end points associated with stage II were comparable to the risks associated with isolated systolic hypertension. Isolated diastolic hypertension did not significantly increase the risk of all-cause mortality in either gender or of cardiovascular mortality in men. In women the risk of cardiovascular disease associated with isolated diastolic hypertension was almost threefold higher compared with the normotensive group, but the risk was not statistically significant. CONCLUSION: In the middle-aged Polish population, isolated systolic hypertension is a much better predictor of cardiovascular disease and all-cause mortality than isolated diastolic hypertension. The association was stronger for stage II than for stage I. The risk of examined end points associated with stage II were similar to those associated with combined systolic-diastolic hypertension. (c)2000 by Le Jacq Communications, Inc.

Journal Article↗
PubMed2003

[Left ventricular systolic and diastolic dysfunction in patients with chronic renal failure treated with hemodialysis].

Systolic and diastolic left ventricular dysfunction is common and important predictor of risk of death in end-stage renal failure. Systolic dysfunction is defined echocardiographically by a shortening fraction < 25% or an ejection fraction < 40%. Systolic dysfunction has a poor prognosis, strongly associated with myocardial ischemia and left ventricular hypertrophy (LVH). Diastolic dysfunction combines relaxation problems with compliance abnormalities and usually is associated with LVH. It is not clinically possible to distinguish systolic from diastolic LV dysfunction. This underlines the importance of echocardiographic diagnosis. In the present study we have analysed echocardiographically the left ventricular systolic and diastolic function and some possible risk factors contributing to its dysfunction development in patients with chronic renal failure (crf) treated by hemodialysis (HD). From a cohort of 85 patients with crf we selected for analysis 59 clinically stable patients. Echocardiography (ECHO), ECG, body mass index (BMI), serum creatinine, urea, total protein, albumin, hemoglobin, hematocrit, electrolytes, endothelin (ET-1) and parathyroid hormone (PTH) concentrations were evaluated in all patients after HD session. In all HD patients systolic and diastolic LV dysfunction was observed as well as LVH: concentric LVH was detected by ECHO in 46 patients and in 13 patients excentric LVH was observed. Mean serum concentrations of urea, creatinine, endothelin (ET-1), PTH and phosphate were increased while serum concentration of hemoglobin, total protein, albumin, sodium, potassium, calcium were in the normal range. Positive correlation was found between PTH serum concentration and LVM r = 0.704 (p < 0.001), between PTH serum concentration and IVS r = 0.267 (p < 0.04), between PTH serum concentration and PW r = -0.238 (p < 0.04), between ET-1 and RWT r = 0.447 (p < 0.04) and negative correlation between BMI and LVMI r = -0.451 (p < 0.05). Our observations suggests that uremic cardiomyopathy is heterogenous (systolic and diastolic dysfunction) and multifactoral. The correlations between serum PTH concentration and LVH and between BMI and LVH confirmed that both hyperparathyroidism and malnutrition are important factors influencing the development of LVH which plays an important role in the systolic and diastolic cardiac failure in HD patients.

Adult↗
PubMed2006

[Comparative study on characteristics of congestive heart failure patients with preserved versus abnormal left ventricular systolic function and evaluation effects of therapy].

OBJECTIVE: To compare clinical characteristics and effects of therapy for hospitalized patients with congestive heart failure (CHF) and different left ventricular ejection fraction (LVEF) during hospitalization. METHODS: The medical records of 1 074 unselected consecutive patients with CHF who were admitted to Queen Mary Hospital from January, 2001 to January, 2002 were retrospectively reviewed. Three hundred and ninety-nine patients were categorized as having either normal left ventricular systolic function or systolic dysfunction based on the results of echocardiography. Clinical features with a slightly modified version of the Framingham criteria, laboratory results and drug therapies at discharge were compared. RESULTS: Among patients, the majority were women, 95.5% were > or =65 years and 50.6% > or =80 years of age. Classification of the severity of heart failure showed that 70.2% were New York Heart Association (NYHA) III and IV. Only 399 patients had borderline LVEF at the time of hospitalization, of these patients 191 (47.9%) had preserved systolic function (LVEF > or =0.50), and 208 (52.1%) with LVEF<0.50. Patients with LVEF > or =0.50, who tended to be elderly and more often female, exhibited a lower incidence of coronary artery disease and diabetes than patients with LVEF<0.50 (all P<0.05). Patients with preserved systolic function had a significantly higher prevalence of auricular fibrillation (P<0.05), accounting for up to 84 patients (44.0%) with it, and number of hospitalization for CHF increased. Among patients with systolic dysfunction, 22.6% were discharged on a therapeutic regimen of digoxin, 63.0% on an angiotensin-converting enzyme inhibitor (ACEI), and 12.0% on a beta-blocker, 13.9% on a calcium channel blocker. These accounted for 62.3%, 35.1%, 9.4% and 18.3% in patients with preserved systolic function, respectively. There was a higher incidence of use of digoxin (P<0.05). CONCLUSION: In hospitalized patients with heart failure, the clinical signs and symptoms of chronic heart failure are similar to those of patients with CHF, LVEF is a powerful prognostic predictor to distinguish CHF patients with normal systolic function from those with systolic dysfunction. Criteria for use of ACEI and beta-blocker are still not clear cut. It is important to differentiate CHF patients with LVEF<0.50 from that with LVEF> or =0.50 in order to achieve a better therapeutic result in the treatment of CHF.

Aged↗
PubMed1991

Assessment of systolic thickening with thallium-201 ECG-gated single-photon emission computed tomography: a parameter for local left ventricular function.

We measured left ventricular (LV) systolic thickening expressed as a systolic thickening ratio in 28 patients, using 201Tl ECG-gated SPECT. Five normals, 15 patients with prior myocardial infarction, 5 with hypertrophic cardiomyopathy, and 3 with dilated cardiomyopathy were studied. The systolic thickening ratio was calculated as [(end-systolic--end-diastolic pixel counts) divided by end-diastolic pixel counts], using the circumferential profile technique of both end-diastolic and end-systolic short axial images. Functional images of the systolic thickening ratio were also displayed with the "bull's-eye" method. The mean systolic thickening ratio thus calculated were as follows: normals, 0.53 +/- 0.05 (mean +/- 1 s.d.); non-transmural prior myocardial infarction, 0.33 +/- 0.09; transmural prior myocardial infarction, 0.14 +/- 0.05; hypertrophic cardiomyopathy in relatively nonhypertrophied areas, 0.56 +/- 0.11; hypertrophic cardiomyopathy in hypertrophied areas, 0.23 +/- 0.07; and dilated cardiomyopathy, 0.19 +/- 0.02. The systolic thickening ratio analysis by gated thallium SPECT offers a unique approach for assessing LV function.

Cardiomyopathy, Dilated↗
PubMed1990

[Morphological and functional parameters of the left ventricle (mass, wall thickness and end-systolic stress) in school children with different levels of blood pressure, at rest and during maximal exercise].

Echocardiographically determined left ventricular mass, diastolic septal and posterior wall thickness and end-systolic wall stress, as well as electrocardiographic indexes of left ventricular enlargement (Sokolow-Lyon index and Romhilt-Estes score) and of left atrial enlargement (P terminal index) were correlated with resting and exercise systolic and diastolic blood pressures, and with several parameters of body size (weight, height, body surface area, Quetelet index), in 130 school children (61 boys, 69 girls) 6 to 15 years of age. Parameters of body size had a positive correlation both with systolic and diastolic blood pressures and with parameters of left ventricular size. Thus, the latter were adjusted for body surface area, for correlation with blood pressure. Left ventricular mass and diastolic septal and posterior wall thickness had a very poor correlation with resting and exercise diastolic blood pressures. Left ventricular mass and diastolic posterior wall thickness had a significantly higher correlation with peak exercise systolic blood pressure than with resting systolic blood pressure. End-systolic wall stress had a positive correlation with resting diastolic and systolic blood pressures. Electrocardiographic parameters of left ventricular and left atrial enlargement had a very poor correlation with resting and exercise blood pressure. Our findings suggest that early in life left ventricular mass and wall thickness are more closely related to maximal systolic blood pressure during physical exercise than to blood pressure in basal conditions. The electrocardiogram is an insensitive method to detect early modifications of left ventricular size in relation to different levels of blood pressure. The echocardiogram is the method of choice for this purpose.

Adolescent↗
PubMedDate not supplied

Prevalence of isolated systolic hypertension in Alameda County, California.

Clinical research has suggested that isolated systolic hypertension differs from essential hypertension in terms of pathophysiological change. Yet little is known of the descriptive epidemiology of isolated systolic hypertension. This paper examines the prevalence of isolated systolic hypertension in biracial Alameda County, California. Baseline survey data from the Alameda County Hypertension Project (1978) were used to calculate age and sex percentage of prevalence by race. This condition was rare below age 40, but the percentage of prevalence increased with age. Defining isolated systolic hypertension as diastolic blood pressure less than 90 and systolic blood pressure greater than 160, age-adjusted prevalence was 1.15, 1.31, 1.01, and 2.47 for white men, black men, white women, and black women, respectively. Comparison with the prevalence estimates of isolated systolic hypertension from biracial, rural Evans County, Georgia, indicated that the Alameda County prevalence was significantly lower for white women (p less than .01), black women (p less than .03), and total population (p less than .01). We posit that the larger number of people under care for essential hypertension is responsible for the lower occurrence of pure, isolated systolic hypertension in Alameda County. The results suggest the importance of female family members in the acceptance and promulgation of health promotion efforts for both essential and isolated systolic hypertension at the population level.

Adult↗
PubMed1978

The influence of heart rate, age, blood pressure, obesity, and work on systolic and diastolic time intervals.

Systolic and diastolic time intervals were measured in 655 men who did not have coronary or hypertensive heart disease. The correlation between systolic and diastolic intervals (STI) and the heart rate, age, height, weight, weight/height index, blood pressure and work heaviness were calculated using multiple stepwise regression analysis. There was a significant correlation between heart rate and the majority of STI. Also there was a significant influence of systolic and diastolic blood pressure and age on the ejection variables (QS2, LVET, S1S2). The PEP and ICT were influenced by heart rate, and systolic and diastolic blood pressure. The PEP/LVET ratio was dependent on diastolic and systolic blood pressure. The height of the A wave of apex cardiogram was significantly dependent on diastolic and systolic blood pressure, obesity, heart rate, and age. The IRT was dependent on heart rate, obesity, and height. When interpreting systolic time intervals one must use systolic time interval indices which are calculated by using the effect of heart rate on them, but in some cases the effect of other factors must be taken into account because blood pressure, age, and obesity also have a significant physiological effect on the STI values.

Adolescent↗
PubMed2004

Relationship between ambulatory blood pressure and follow-up clinic blood pressure in elderly patients with systolic hypertension.

BACKGROUND: Patients with elevated clinic blood pressure and normal ambulatory blood pressure have a better prognosis than patients with sustained ambulatory hypertension, and may not have to be treated with antihypertensive drugs. On the contrary, current guidelines emphasize repeated clinic blood pressure measurements for the initiation of antihypertensive therapy. OBJECTIVE: To examine the relationship between ambulatory blood pressure at baseline and clinic blood pressure after 6 months of follow-up in untreated hypertensive patients, and the relationships of these pressures with the subsequent incidence of cardiovascular events. METHODS: Patients who were > or = 60 years old, with systolic clinic blood pressure of 160-219 mmHg and diastolic pressure < 95 mmHg, participated in the Systolic Hypertension in Europe trial. The relationship between ambulatory blood pressure at baseline and clinic blood pressure after 6 months of follow-up was examined in 295 patients enrolled in the Ambulatory Blood Pressure Monitoring substudy and randomized to the placebo arm, and who were still on double-blind treatment and not taking other antihypertensive drugs after 6 months follow-up. RESULTS: Age averaged 70 +/- 6 years, 41% were men, and baseline daytime ambulatory blood pressure was 152 +/- 16/84 +/- 10 mmHg; clinic blood pressure decreased from 173 +/- 10/86 +/- 6 mmHg at baseline to 163 +/- 20/85 +/- 9 mmHg at month 6. Systolic daytime ambulatory blood pressure at baseline and systolic clinic blood pressure at month 6 were considered normal if < 140 mmHg. Of the 74 patients with normal systolic daytime ambulatory blood pressure at baseline, only seven (9.5%) had a normal systolic clinic blood pressure during follow-up. Conversely, of the 24 patients with normal follow-up clinic blood pressure, only seven (29%) had a normal systolic daytime ambulatory blood pressure at baseline. The incidence of cardiovascular events beyond the 6-month visit was significantly related to baseline ambulatory blood pressure but not to follow-up clinic pressure. CONCLUSIONS: Baseline daytime ambulatory blood pressure and follow-up clinic blood pressure do not identify the same patients for antihypertensive treatment. Baseline ambulatory pressure is a better predictor of cardiovascular events than follow-up clinic pressure.

Aged↗
PubMed1997

Single-beat estimation of the ventricular pumping mechanics in terms of the systolic elastance and resistance.

An elastance-resistance model has long been used to assess the systolic mechanical behavior of the ventricular pump under an in situ, open-chest experiment. However, there is difficulty in the clinical application of such a model because of the required isovolumetric signal that is obtained by occluding the ascending aorta in diastole. In this study, we determine the characteristics of an elastance-resistance model in the absence of isovolumeric measurement to quantify the physical properties of the left ventricle. A high-fidelity multisensor catheter was used to record the left ventricular pressure and ascending aortic flow in nine anesthetized, closed-chest dogs. The isovolumetric pressure was estimated from the instantaneous pressure of an ejecting contraction by a curve-fitting technique. Thus, the parameters in the characterization of systolic pumping mechanics could be inferred by the use of fitting this elastance-resistance model. The results showed that the maximal systolic elastance was 7.3 +/- 2.8 mmHg and theoretical maximum flow was 494 +/- 194 ml s-1. These data were compatible with other reports in the literature. Moreover, in every dog studied the maximal systolic elastance was smaller than the end-systolic elastance which was determined by using the end-systolic pressure-volume relation. We suggested that an elastance-resistance model with the estimated isovolumetric pressure has the potential to measure the intrinsic systolic mechanics of the left ventricle in a closed-chest cardiovascular system.

Animals↗
PubMedDate not supplied

Application of an end-systolic pressure-segment length relationship for measuring regional contractility.

A method for estimating regional contractility is described using the end-systolic relationship between left ventricular pressure and myocardial segment-lengths in rapidly volume-loaded beats. The approach was based on the success of previously developed end-systolic relationships between left ventricular pressure and volume and between variable ejection force and fiber length used to describe global contractility in beating hearts. The regional end-systolic relationship was more complicated than its global counterpart, which was load independent, and appeared curvilinear to rapid volume loading. As an approximation of this relationship, a linear slope was constructed between maximum and minimum (pre-ejection) loaded beats of equal cycle length. Because of its load dependency and in order to compare slope relationships between interventions, slope functions were derived only from similarly loaded beats either within or between interventions. Slopes generated by this technique had a reasonable constancy at control conditions and coronary flows with an average SEM of 9.1% of the slope means. End-systolic slopes also appeared sensitive to changes in contractile state, increasing appropriately following treatments with dobutamine and decreasing after propranolol. Following shifts in the end-systolic slopes were unreliable, however, in describing the regional changes in contractility with ischemia. At milder levels of flow restriction, the slopes declined as expected. At moderate levels of flow restriction, the pressure-segment loops shifted markedly rightward and the slope increased. At advanced levels of ischemia, the loops were so distorted, that end-systole could not be identified accurately and the loops essentially described the diastolic compliance characteristics of the left ventricle. Thus the slope estimates of regional contractility as described in this report provided a reliable assessment of inotropic background during modifications with positive and negative inotropic drugs but became invalid as systolic shortening was replaced by aneurysmal bulging during high-grade ischemia.

Animals↗
PubMed1986

Coronary extravascular compression influences systolic coronary blood flow.

The purpose of this study was to determine whether a relation exists between systolic coronary blood flow and systolic coronary extravascular compressive forces. Studies were performed in seven open-chest dogs in which the left anterior descending coronary artery was cannulated and perfused from the left carotid artery. Pressure within the left ventricular subepicardium, a measure of coronary extravascular compression in the subepicardium, was measured with a 1-mm-diameter catheter-tip micromanometer inserted directly into the myocardium in the region of perfusion. Systolic extravascular compressive forces were augmented by a local intracoronary injection of 1 microgram isoproterenol. Measurements were made in the presence of coronary vasomotor tone and were repeated following local maximal vasodilatation with adenosine. In the regulated coronary bed, systolic coronary flow decreased (18 +/- 4 vs -2 +/- 4 ml/min, P less than 0.01) as intramyocardial pressure increased (127 +/- 5 vs 222 +/- 12 mmHg, P less than 0.001). Similarly, in the maximally vasodilated coronary bed, systolic coronary flow decreased (103 +/- 16 vs 38 +/- 11 ml/min, P less than 0.001) as intramyocardial pressure increased (112 +/- 6 vs 204 +/- 16 mmHg, P less than 0.001). These observations indicate that an augmentation of coronary extravascular compressive forces during systole is accompanied by a diminution of systolic coronary flow irrespective of coronary vasomotor tone.

Animals↗
PubMedDate not supplied

Different responses of left ventricular systolic function to changes in right ventricular volume and shortening--comparison between aorto-femoral vein and aorto-left atrium shunts in dog hearts.

It has been reported that left ventricular end-systolic volume decreases during arteriovenous shunt and increases during subclavian artery-left atrium shunt at a constant end-systolic pressure. The mechanism of the opposing changes in end-systolic volume during the two types of shunt is not clear. One possible cause is that left ventricular pump function with enhanced right ventricular ejection differs from that without enhancement. To investigate this hypothesis, we studied the two types of shunt (Aorto-femoral vein shunt, AoFV; aorto-left atrium shunt, AoLA) with matched reduction of systemic vascular resistance in open-chest dogs with beta-blockade. Both right and left ventricular volumes and shortenings were assessed from short-axis views by two-dimensional (2D)-echocardiogram. Left ventricular end-systolic short-axis area decreased from 76 +/- 3 to 62 +/- 3% in AoFV shunt (p less than 0.05), but tended to increase in AoLA shunt (76 +/- 4 in control state vs 81 +/- 5% in AoLA, NS) in spite of a similar reduction in left ventricular end-systolic pressure. There was no difference in left ventricular shortening, but significant differences were observed in right ventricular shortening (50 +/- 8 in AoFV vs 24 +/- 7% in AoLA, p less than 0.05) and right ventricular short-axis area at end-diastole (142 +/- 6 in AoFV vs 96 +/- 3% in AoLA, p less than 0.01), and at end-systole (92 +/- 8 in AoFV vs 73 +/- 7% in AoLA, p less than 0.05) between the two types of shunt. We conclude that the different changes in left ventricular end-systolic short-axis area found in the two shunts are not caused by the different left ventricular shortenings, but by the different right ventricular mechanical actions. These findings suggest that left ventricular pumping action in the high output state changes, depending on whether it is accompanied by augmented ejection of the right ventricle or not.

Animals↗
PubMed2006

Myocardial systolic strain abnormalities in patients with acromegaly: a prospective color Doppler imaging study.

BACKGROUND: Heart abnormalities are frequent findings in patients with acromegaly: systolic abnormalities are considered to be secondary to diastolic changes. AIM: The aim of the study was to evaluate whether early systolic abnormalities might be revealed in acromegalic patients using the high sensitive color Doppler myocardial imaging (CDMI) technique. PATIENTS AND METHODS: Twenty-two consecutive acromegalic patients with active untreated disease (ACROUNTR) were evaluated at baseline and after a 6-month course with SS analogs (SSa) (ACROSSa); 25 healthy subjects served as controls. All subjects underwent conventional 2D-color Doppler echocardiography, pulse wave tissue Doppler imaging (PW-TDI) and CDMI. RESULTS: Mean left ventricular (LV) ejection fraction did not differ in ACROUNTR and in controls; at variance, ACROUNTR patients had reduced mean LV diastolic function (E/A ratio: 0.96+/-0.3 vs controls: 1.6+/-0.3; p<0.002). Impairment of global LV diastolic function was confirmed by PW-TDI in ACROUNTR patients having a normal systolic function. Regional myocardial systolic strain (epsilon) and strain rate (SR) values, indices of regional systolic heart deformation, were lower in ACROUNTR [epsilonsys (S) -19.8+/-2.9 and epsilonsys (L): -17.7+/-2.2] than in controls [epsilonsys (S): -27.9+/-3.8; p<0.001 and epsilonsys (L): -25.3+/-2.6; p<0.001]. In addition, the early phase of diastolic function, evaluated using SR parameters, was impaired in acromegalic patients (p<0.005 vs controls). Strain and SR values were related to serum GH and IGF-I levels (p<0.02) and greatly improved after a 6-month course with SSa [epsilonsys (S) improved to -23.8+/-3.8 (p<0.05) and epsilonsys (L) improved to -24.7+/-2.4 (p<0.03)]. CONCLUSIONS: Our study confirms that ACROUNTR patients have impaired diastolic function. More important, our study clearly shows that ACROUNTR patients have an impairment of regional myocardial systolic function, which is not secondary to diastolic changes. These intramyocardial functional abnormalities improved during medical treatment of acromegaly. It is conceivable that GH-IGF-I excess has detrimental effects either on the diastolic or the systolic phases of heart function.

Acromegaly↗
PubMed2003

[Systolic hypertension-treat or not to treat?].

UNLABELLED: HEMODYNAMICS: Elevated diastolic as well as elevated systolic blood pressure substantially contribute to the increase of cardiovascular risk. Conclusive results have proven that lowering diastolic and/or systolic blood pressure can reduce cardiovascular risk. There is evidence that not only the absolute values for diastolic and systolic blood pressure alone but also the pulse pressure as an additional indicator of cardiovascular risk have to be considered. The prevalence of isolated systolic hypertension increases with age. Remodeling of the arterial wall with increase of collagen and decrease of elastic fibers are leading to an impaired arterial compliance. Decreased compliance and acceleration of the pulse wave velocity can elevate systolic and lower diastolic blood pressure. In consequence cardiac stress and pulse pressure will rise. CONCLUSION: There is a strong correlation in elderly patients between cardiovascular mortality and morbidity and systolic blood pressure. Antihypertensive therapy is able to lower cardiovascular event rate in elderly patients with isolated systolic hypertension with a predominant risk reduction for stroke.

Aged↗