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PubMed1995

Changes in effective regurgitant orifice throughout systole in patients with mitral valve prolapse. A clinical study using the proximal isovelocity surface area method.

BACKGROUND: In patients with mitral valve prolapse, spontaneous changes of the effective regurgitant orifice during systole are not well documented. Such changes can now be analyzed by use of the proximal isovelocity surface area method, but the changes raise concern about the reliability of this method for assessing overall severity of regurgitation in these patients. METHODS AND RESULTS: In a prospective study of 42 patients with mitral valve prolapse, the effective mitral regurgitant orifice was calculated at four phases of systole (early, mid, mid-late, and late) as the ratio of regurgitant flow to regurgitant velocity by use of the proximal isovelocity surface area method. Throughout systole, the effective regurgitant orifice increased significantly, from 32 +/- 27 mm2 in early systole to 41 +/- 27 in midsystole, 55 +/- 30 in mid-late systole, and 107 +/- 66 mm2 during late systole (P < .0001). Phasic regurgitant volume increased from early to mid-late systole but decreased in late systole. For quantitation of the overall effective regurgitant orifice, four approaches using the proximal isovelocity surface area were compared with simultaneously performed quantitative Doppler echocardiography (54 +/- 30 mm2) and quantitative two-dimensional echocardiography (51 +/- 29 mm2). All correlations were good (r > .95), but overestimation was considerable when the largest flow convergence was used (70 +/- 39 mm2; both P < .0001), significant when the simple mean of the four phases was used (59 +/- 36 mm2; P = .005 and P = .0007, respectively), mild when a weighted mean of the four phases was used (55 +/- 33 mm2; P = .41 and P = .01, respectively), and no overestimation was observed when the effective regurgitant orifice calculated at maximum regurgitant velocity was used (54 +/- 30 mm2; P = .29 and P = .17, respectively). CONCLUSIONS: Phasic changes of mitral regurgitation are observed in patients with mitral valve prolapse. The effective regurgitant orifice increases throughout systole. Regurgitant volume also increases initially but tends to decrease in late systole. These changes can lead to overestimation of the overall degree of regurgitation, but properly timed measurements made by use of the proximal isovelocity surface area method allow an accurate estimation of the overall effective regurgitant orifice.

Aged↗
PubMed1985

Effect of alteration of left ventricular activation sequence on the left ventricular end-systolic pressure-volume relation in closed-chest dogs.

We investigated the effect of pacing from the atrium and various ventricular sites on the left ventricular end-systolic pressure-volume relation following autonomic blockade in a total of 10 dogs chronically instrumented to measure left ventricular pressure and determine left ventricular volume from three ultrasonic endocardial dimensions. During ventricular pacing, left ventricular end-diastolic volume, stroke volume, and end-systolic pressure were decreased, while the end-systolic volume was relatively unchanged. Left ventricular end-systolic pressure-volume relations were generated by vena caval occlusions during pacing at a constant rate from the left atria, and the epicardium of the right ventricular free wall, right ventricular apex, and left ventricular free wall. The left ventricular end-systolic pressure-volume relations were described by straight lines for each site (r greater than 0.96 and SEE less than 2.9 mm Hg in all but one instance). Compared to atrial pacing, the left ventricular end-systolic pressure-volume relations were shifted (P less than 0.001) to the right during pacing from ventricular sites. During atrial pacing, the volume intercept of the left ventricular end-systolic pressure-volume relation was 16.0 +/- 7.2 ml (mean +/- SD), and increased to 18.7 +/- 7.8 ml (P less than 0.05) during pacing from the right ventricular free wall, to 19.6 +/- 7.7 ml (P less than 0.05) during pacing from the right ventricular apex, and to 20.0 +/- 7.5 ml (P less than 0.05) during pacing from the left ventricular free wall. These volume intercepts correlated roughly with the extent of dyssynchronous activation as estimated by the QRS duration (r = 0.59 to 0.93) and the time for left ventricular endocardial activation (r = 0.92 and 0.95). During ventricular pacing, the slope of the left ventricular end-systolic pressure-volume relation changed only slightly. Similar results were obtained during pacing from right ventricular endocardial sites. We conclude that alterations of the normal activation sequence produced by ventricular pacing depress left ventricular pumping function independent of loading conditions, as indicated by a rightward shift of the left ventricular end-systolic pressure-volume relation. The extent of this shift appears to be in proportion to the degree of dyssynchronous activation. The decreased stroke volume during ventricular pacing is due both to a decreased end-diastolic volume (decreased preload) and the rightward shift of the end-systolic pressure-volume relation (decreased pump function).

Animals↗
PubMed1986

Analysis of systolic bulging. Mechanical characteristics of acutely ischemic myocardium in the conscious dog.

To determine the mechanical factors affecting regional segmental motion after acute coronary occlusion, we studied seven conscious dogs, instrumented with sonomicrometers. Loading conditions were changed by the withdrawal of 500 ml of blood and the transfusion of 800 ml of blood. To express segmental motion, percent systolic shortening, percent systolic elongation, and early diastolic shortening were calculated. Blood withdrawal decreased left ventricular preload, increased percent systolic elongation (from 6.9 +/- 3.1% to 9.9 +/- 3.5%) and early diastolic shortening (12.9 +/- 5.3% to 16.6 +/- 5.3%), and decreased percent systolic shortening. Blood transfusion increased left ventricular preload, decreased percent systolic elongation (to 5.2 +/- 1.8%) and early diastolic shortening (8.8 +/- 2.9%), and increased percent systolic shortening. Manipulation of loading did not change regional myocardial blood flow. In acutely ischemic myocardium, the tension-length loop showed an exponential upstroke during isovolumic systole and a nearly superimposed exponential downstroke during the isovolumic relaxation phase after systole, compatible with essentially passive movement as seen with an elastic material. The changes in loading conditions affected the tension-length curve to a very minor extent. The uniformity of the curve and its exponential shape explain the load-dependency of systolic bulging and segmental motion. It is concluded that systolic bulging depends on the change in the preload tension due to the compliant portion of tension-length curve, and that shortening of ischemic myocardium during the isovolumic relaxation phase is a completely passive phenomenon.

Animals↗
PubMed2002

Systolic blood pressure: an underestimated cardiovascular risk factor.

Classification of the severity of hypertension and recommendations on the blood pressure values to be achieved during antihypertensive drug treatment have for decades been based on diastolic values. It is now clear, however, that systolic blood pressure is by no means less important. This paper will focus on the following sets of evidence: (1) that epidemiologically a selective elevation of systolic blood pressure has a major prevalence in the elderly population; (2) that isolated systolic hypertension carries a marked increase in the risk of cardiovascular disease and that even in systo-diastolic hypertension this risk may be more closely related to systolic than to diastolic blood pressure; (3) that treatment of systolic hypertension greatly reduces cardiovascular complications and that in all conditions this reduction is related to the treatment-induced reduction in systolic blood pressure to a degree similar to or superior to the relationship with the reduction in diastolic blood pressure; and (4) that in the hypertensive fraction of the population, control of systolic blood pressure is achieved much less often than control of diastolic blood pressure. That this last point is also the case in major intervention trials suggests that normalization of systolic blood pressure may be intrinsically more difficult than normalization of diastolic blood pressure, possibly because of the difficulty of reversing the pathophysiological abnormalities responsible for the elevation of systolic blood pressure. This emphasizes the importance of research into new drugs or treatment types with greater efficacy in systolic hypertension.

Aged↗
PubMed1991

[End-systolic pressure-volume relationships obtained by conductance catheter and transient inferior vena caval occlusion: their clinical usefulness].

Whether beneficial hemodynamic effects of cardiovascular drugs are due to changes in the inotropic or loading conditions has been difficult to determine in clinical settings. In this study, the end-systolic pressure-volume relationship, known as a load-independent measurement of cardiac contractility, was obtained by a volumetric conductance catheter and transient inferior vena caval occlusion. We applied this technique to determine the major mode of hemodynamic action of a new inotropic vasodilator, OPC-8490, in comparison to that of dobutamine. In 7 patients with anterior myocardial infarction, an 8F conductance catheter with pressure micromanometer was inserted into the left ventricle. Absolute volume calibration was accomplished by injection of hypertonic saline into the pulmonary artery. Left ventricular pressures and volumes were simultaneously and continuously measured during transient inferior vena caval occlusion using a balloon catheter. Left ventricular end-systolic pressure-volume relationships were determined during the initial 8-sec of balloon occlusion, before baroreceptor-mediated cardiac stimulation was initiated. OPC-8490 decreased both the left ventricular systolic pressure and end-systolic volume without changing the heart rate. Dobutamine increased the systolic pressure and heart rate but decreased the end-systolic volume. The reduction in the end-systolic volume with dobutamine, was caused by an increase in the slope of the end-systolic pressure-volume relationship, while with OPC-8490, it resulted from a decrease in the end-systolic pressure without an appreciable change in the slope of the end-systolic pressure-volume relationship.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

Applications and limitations of end-systolic measures of ventricular performance.

The usefulness of end-systolic measures of left ventricular performance as a load-independent method of assessing of ventricular contractility has been studied in intact, conscious dogs. The end-systolic pressure-chamber diameter (P-D) relation was shown to be linear, unaltered by preload changes, and shifted in a parallel fashion by inotropic stimulation, whereas the end-systolic pressure-volume relation appeared to increase in slope with increased contractility. A simplified measure of end-systolic relations that does not require measurement of chamber volume or diameter, the end-systolic pressure-wall thickness ( WTh ) relation, was also linear and shifted with acute changes in inotropic state. During regional ischemia, the regional end-systolic WTh relation also may provide a relatively load-independent means of detecting regional depression of myocardial contractility. With chronic pressure overload hypertrophy in dogs, the end-systolic P-D relation was markedly shifted upward and to the left, which indicates hyperfunction of the left ventricle; however, end-systolic wall stress-diameter relations were identical before and after the development of hypertrophy, which suggests that myocardial contractility was unaltered. These findings and clinical studies of mitral regurgitation imply that for assessing resting left ventricular contractility in certain chronic conditions, the use of wall stress rather than pressure may be appropriate in the end-systolic framework. Further experimental studies are needed in the intact circulation to better characterize end-systolic relations before their full potential in the clinical setting can be realized.

Animals↗
PubMed1995

Finger systolic blood pressures: effects of cold provocation on the reference finger.

Finger systolic blood pressure measured after cold provocation and ischemia of a digit is used to assist in the diagnosis of vibration-induced white finger, VWF. A reduction in finger systolic blood pressure after cooling is assumed to indicate vascular dysfunction. The percentage pressure change observed in the tested finger is often corrected for whole body effects (systemic systolic pressure changes) according to the pressure change measured in a reference finger. The commonly used method of correction is based on assumptions as to the causes of any changes occurring in the reference finger. It is assumed that the reference finger is not differentially susceptible to the cold provocation of the test finger, arising from either close proximity to the cold provocation or from a vascular disorder in the reference finger. An experiment has been undertaken to investigate the repeatability, over three days, of measurements of the arm systolic pressures of both arms and the finger systolic pressures in air of four fingers of both hands. The systolic pressures of both arms and of four fingers of one hand were also measured whilst the fifth finger of the same hand was subjected to cold provocation at 10 degrees C. Twelve healthy male subjects were rested in a supine position for 15 minutes in a room at 21-24 degrees C before measurements were taken. Finger systolic blood pressures were recorded using strain gauge plethysmography. The results show that the systolic blood pressure measurements were generally repeatable, but differed with measurement location. Cold provocation of the test finger had little consistent effect on the systolic pressures measured at other locations. The results are interpreted with regard to the correction of finger systolic pressure using a reference measurement.

Adult↗
PubMed1998

Semirigid or flexible mitral annuloplasty rings do not affect global or basal regional left ventricular systolic function.

BACKGROUND: Previous studies have revealed that rigid mitral annuloplasty rings may be associated with left ventricular (LV) systolic dysfunction, but whether ring type affects regional systolic function at the base of the LV, in the region near the mitral annulus, is unclear. We tested the hypothesis that rigid fixation of the mitral annulus results in significant regional systolic dysfunction at the base of the LV. METHODS AND RESULTS: Twenty-six adult male sheep underwent placement of 13 miniature tantalum markers into the LV epicardium and around the mitral annulus to allow calculation of LV volume and regional epicardial area. Group I (n = 7) sheep served as controls; animals randomized to groups II (n = 11) and III (n = 8) underwent mitral annuloplasty with either a semirigid or flexible ring, respectively. After a 7- to 10-day recovery period, animals were studied in a closed-chest, sedated, autonomically blocked state. Global LV systolic function (end-systolic elastance and preload recruitable stroke work) were not significantly different among the 3 groups (P = 1.0, ANOVA). Regional systolic function at the base of the LV (fractional area shrinkage [FAS] of 4 epicardial areas) at comparable LV preload and afterload was similar in the 4 basal areas (P = 0.223, MANOVA). With the use of load-insensitive indexes (slope and area intercept of the end-systolic pressure-regional area relationship and regional stroke work-end-diastolic area relationship), regional systolic function also was not different between groups at baseline or with inotropic stimulation in any basal region (P > 0.05, MANOVA). Furthermore, neither annuloplasty ring perturbed the regional pattern of basal LV systolic function. CONCLUSIONS: Postoperative LV systolic function, both globally and in the region of the base of the LV (near the mitral annulus), was not altered with either semirigid or flexible ring fixation of the mitral annulus.

Animals↗
PubMed1985

Upper- vs lower-limb systolic blood pressure in full-term normal newborns.

The difference between upper- vs lower-limb systolic blood pressure (BP) was investigated in 100 normal full-term newborns younger than 24 hours of age by the oscillometric method. The mean systolic BP of both upper limbs was 72.3 +/- 7.6 mm Hg (mean +/- SD). The mean +/- SD systolic BP of both lower limbs was 71.3 +/- 8.2 mm Hg. Systolic BP in the upper limb was greater than that in the lower limb in 66% of newborns by as much as 20 mm Hg (mean +/- SD, 3.5 +/- 3.1). Systolic upper-limb BP was lower than systolic lower-limb BP in 28% of newborns by as much as 21 mm Hg (mean +/- SD, 5.1 +/- 5.1). Systolic BP did not correlate with birth weight. Follow-up evaluation of BP in 25 of the infants up to 3 years of age revealed higher systolic BP in the lower extremities in 24 of the 25 infants. We conclude that (1) it is normal to have a higher systolic BP in either the upper limb or the lower limb in newborns younger than 24 hours of age, and (2) there is no correlation of systolic BP with birth weight in full-term normal neonates younger than 24 hours of age.

Arm↗
PubMed2001

Mortality and readmission of hospitalized patients with congestive heart failure and preserved versus depressed systolic function.

Patients with congestive heart failure (CHF) and preserved systolic function are very common. Despite the high prevalence of this syndrome, very little information is known regarding its mortality and morbidity (e.g., readmission), or the efficacy of drugs. The purpose of this study was to compare the clinical characteristics and prognosis among consecutively hospitalized patients with CHF and preserved versus depressed left ventricular systolic function. Patients with severe aortic or mitral valve disease were excluded from the study. Patients were categorized based on the values of ejection fraction (EF) as having "preserved" (EF>50%), "intermediate" (EF 40% to 50%), or "depressed" (EF<40%) systolic function. Clinical characteristics as well as mortality and hospital readmission rates during 2.4 years of follow-up were recorded for each patient. Sixty-one patients (35%) had preserved systolic function, 73 (43%) had depressed function, and 38 (22%) had intermediate function. Patients with preserved systolic function were more often women and had a higher prevalence of left ventricular hypertrophy (all p <0.05). At follow-up, cumulative survival probabilities were similar between patients with preserved systolic function and those with systolic dysfunction (p = 0.84). Readmission rates were also comparable between preserved and depressed systolic function (36% vs 48%; p = NS). The prognosis of CHF patients with preserved systolic function was similar to those with systolic dysfunction. In light of these findings, effective therapeutic strategy for this subset of patients is needed.

Aged↗
PubMed1977

Variations in and significance of systolic pressure during maximal exercise (treadmill) testing.

Variations in clinical noninvasive systolic pressure at the point of symptom-limited exercise on a treadmill were examined in six groups of subjects: 5,459 men and 749 women classified into three categories each. Among the men, 2,532 were asymptomatic healthy, 592 were hypertensive and 1,586 had clinical manifestations of coronary heart disease (that is, typical angina pectoris, prior myocardial infarction or sudden cardiac arrest with resuscitation). Among the women, 244, 158 and 347 were in the corresponding clinical categories. None had had cardiac surgery; all had follow-up status ascertained by periodic mail questionnaires. Reported deaths were reviewed and classified by three cardiologists; 140 deaths were attributed to coronary heart disease, 118 of them in the men classified as having coronary heart disease. The majority of maximal systolic blood pressure readings were reported to the nearest centimeter rather than millimeter of pressure. Retesting of 156 persons from 1 to 32 months later showed that pressure values agreed within 10 percent in two thirds, the overall mean difference was only 8.6 mm Hg and the correlation at maximal exercise was superior to that of the resting observations just before exercise. Hypertensive patients had a significantly greater body weight than normotensive persons. Among men, the lowest maximal systolic pressure was observed in the group with coronary heart disease; among women, the lowest mean pressure was found in the healthy group. Patients with coronary heart disease were slightly older, and only the women showed a significant correlation in maximal pressure with age. Only 5 percent of the variation in maximal systolic pressure in the patients with coronary heart disease was due to a shortened duration of exercise. Maximal systolic pressures correlated fairly well (r equals 0.46 to 0.68 for the various groups) with resting systolic pressure, and this relation was independent of the diagnosis of cardiovascular disease in both men and women. Relations between pressure and the number of stenotic coronary arteries and imparied ejection fraction at rest were examined in 22 men without and 182 men with coronary artery disease. Lower maximal systolic pressures were often associated with two or three vessel disease or reduced ejection fraction, or both. The prognostic value of maximal systolic pressure for subsequent death due to coronary heart disease was examined in the men with coronary heart disease. The annual rate of sudden cardiac death decreased from 97.9 per 1,000 men to 25.3 and 6.6 per 1,000 men as the range of maximal systolic pressure increased from less than 140 to 140 to 199 and to 200 mm Hg or more, respectively. Cardiomegaly, Q waves in the resting electrocardiogram and persistent postexertional S-T depression were more common in men with the lowest systolic pressure at maximal exercise.

Adult↗
PubMed2000

Risks of untreated and treated isolated systolic hypertension in the elderly: meta-analysis of outcome trials.

BACKGROUND: Previous meta-analysis of outcome trials in hypertension have not specifically focused on isolated systolic hypertension or they have explained treatment benefit mainly in function of the achieved diastolic blood pressure reduction. We therefore undertook a quantitative overview of the trials to further evaluate the risks associated with systolic blood pressure in treated and untreated older patients with isolated systolic hypertension METHODS: Patients were 60 years old or more. Systolic blood pressure was 160 mm Hg or greater and diastolic blood pressure was less than 95 mm Hg. We used non-parametric methods and Cox regression to model the risks associated with blood pressure and to correct for regression dilution bias. We calculated pooled effects of treatment from stratified 2 x 2 contingency tables after application of Zelen's test of heterogeneity. FINDINGS: In eight trials 15 693 patients with isolated systolic hypertension were followed up for 3.8 years (median). After correction for regression dilution bias, sex, age, and diastolic blood pressure, the relative hazard rates associated with a 10 mm Hg higher initial systolic blood pressure were 1.26 (p=0.0001) for total mortality, 1.22 (p=0.02) for stroke, but only 1.07 (p=0.37) for coronary events. Independent of systolic blood pressure, diastolic blood pressure was inversely correlated with total mortality, highlighting the role of pulse pressure as risk factor. Active treatment reduced total mortality by 13% (95% CI 2-22, p=0.02), cardiovascular mortality by 18%, all cardiovascular complications by 26%, stroke by 30%, and coronary events by 23%. The number of patients to treat for 5 years to prevent one major cardiovascular event was lower in men (18 vs 38), at or above age 70 (19 vs 39), and in patients with previous cardiovascular complications (16 vs 37). INTERPRETATION: Drug treatment is justified in older patients with isolated systolic hypertension whose systolic blood pressure is 160 mm Hg or higher. Absolute benefit is larger in men, in patients aged 70 or more and in those with previous cardiovascular complications or wider pulse pressure. Treatment prevented stroke more effectively than coronary events. However, the absence of a relation between coronary events and systolic blood pressure in untreated patients suggests that the coronary protection may have been underestimated.

Aged↗
PubMed2003

High prevalence of left ventricular systolic and diastolic asynchrony in patients with congestive heart failure and normal QRS duration.

OBJECTIVE: To study the possible occurrence of left ventricular (LV) systolic and diastolic asynchrony in patients with systolic heart failure (HF) and narrow QRS complexes. DESIGN: Prospective study. SETTING: University teaching hospital. PATIENTS: 200 subjects were studied by echocardiography. 67 patients had HF and narrow QRS complexes (< or = 120 ms), 45 patients had HF and wide QRS complexes (> 120 ms), and 88 served as normal controls. INTERVENTIONS: Echocardiography with tissue Doppler imaging was performed using a six basal, six mid-segmental model. MAIN OUTCOME MEASURES: Severity and prevalence of systolic and diastolic asynchrony, as assessed by the maximal difference in time to peak myocardial systolic contraction (T(S)) and early diastolic relaxation (T(E)), and the standard deviation of T(S) (T(S)-SD) and of T(E) (T(E)-SD) of the 12 LV segments. RESULTS: The mean (SD) maximal difference in T(S) (controls 53 (23) ms v narrow QRS 107 (54) ms v wide QRS 130 (51) ms, both p < 0.001 v controls) and in T(S)-SD (controls 17.0 (7.8) ms v narrow QRS 33.8 (16.9) ms v wide QRS 42.0 (16.5) ms, both p < 0.001 v controls) was prolonged in the narrow QRS group compared with normal controls. Similarly, the maximal difference in T(E) (controls 59 (19) ms v narrow QRS 104 (71) ms v wide QRS 148 (87) ms, both p < 0.001 v controls) and in T(E)-SD (controls 18.5 (5.8) ms v narrow QRS 33.3 (27.7) ms v wide QRS 48.6 (30.2) ms, both p < 0.001 v controls) was prolonged in the narrow QRS group. The prevalence of systolic and diastolic asynchrony was 51% and 46%, respectively, in the narrow QRS group, and 73% and 69%, respectively, in the wide QRS group. Stepwise multiple regression analysis showed that a low mean myocardial systolic velocity from the six basal LV segments and a large LV end systolic diameter were independent predictors of systolic asynchrony, while a low mean myocardial early diastolic velocity and QRS complex duration were independent predictors of diastolic asynchrony. CONCLUSIONS: LV systolic and diastolic mechanical asynchrony is common in patients with HF with narrow QRS complexes. As QRS complex duration is not a determinant of systolic asynchrony, it implies that assessment of intraventricular synchronicity is probably more important than QRS duration in considering cardiac resynchronisation treatment.

Aged↗
PubMed2004

A pilot study of the effect of altering airway pressure on systolic pulse pressure variation in the systemic and pulmonary arterial circulations.

OBJECTIVE: Systolic pressure variation results from cyclical fluctuation in the intra-thoracic pressure associated with mechanical ventilation and has been used as a measure of relative hypovolemia in mechanically ventilated patients. The impact of the magnitude of the tidal volume and airway pressure on systolic pressure variation, however, has not been examined in mechanically ventilated patients. METHODS: Two patients underwent monitoring following elective cardiac surgery. Tidal volume was randomly varied between 3 and 11 mL/kg over a two minute interval, and the corresponding airway pressure was monitored, as were the effects on the systolic pressure variation of the systemic and pulmonary circulations. RESULTS: There was a strong correlation between increasing tidal volume and peak airway pressure (p<0.0001). In addition, peak airway pressure strongly correlated with the systolic pressure variation of both the systemic and pulmonary circulations (p<0.0001). The increase in diastolic pulmonary arterial pressure induced by insufflation correlated well with the associated increase in systolic blood pressure (p<0.0001). Similarly, the increase in systolic pulmonary artery pressure (PAP) correlated with the associated decrease in systolic blood pressure induced by insufflation (p<0.0001). CONCLUSIONS: Systolic pressure variation in the systemic and pulmonary circulations is affected by tidal volume and peak airway pressure. This should be considered when using systolic pressure variation as a marker of intravascular volume status. Our findings regarding the correlations between changes in the pulmonary arterial pressure and the systemic arterial pressure induced by mechanical ventilation are consistent with the proposed physiological mechanisms of systolic pressure variation.

Journal Article↗
PubMed1996

Associations of orthostatic blood pressure fall in older patients with isolated systolic hypertension. Syst-Eur Investigators.

OBJECTIVES: To investigate the associations of the orthostatic blood pressure changes in older patients with isolated systolic hypertension. METHODS: A total of 2716 patients, 917 men and 1799 women, aged > or = 60 years, were examined at three separate outpatient visits whilst receiving placebo during the single-blind run-in phase of the Syst-Eur trial. The orthostatic blood pressure changes were calculated by subtracting the average of two blood pressure readings with the patient in the supine position from the mean of two readings obtained after the patient had stood for 2 min. An orthostatic blood pressure drop by at least 20 mmHg systolic or 10 mmHg diastolic was considered exaggerated. RESULTS: For the three run-in visits combined, the supine blood pressure was 175 +/- 13 mmHg systolic and 86 +/- 6 mmHg diastolic (means +/- SD). With the patients standing the systolic blood pressure was 5 +/- 12 mmHg lower, whereas the diastolic blood pressure was 2 +/- 7 mmHg higher. An exaggerated fall in systolic blood pressure was observed on at least 1 visit in 21.0% of the patients and on all three visits in 2.5%. The corresponding values for diastolic blood pressure were 9.7 and 0.4%. The orthostatic fall in systolic blood pressure increased with previous antihypertensive treatment, age and smoking, but decreased with a higher sitting pulse rate and usual alcohol consumption versus none. The rise in diastolic blood pressure upon standing was higher in women than in men, was curvilinearly associated with age and increased with the sitting diastolic blood pressure. By multiple logistic regression analysis, the odds of having a persistent or occasional exaggerated orthostatic fall in systolic blood pressure were 22% higher in women than in men. The odds increased with previous antihypertensive treatment (by 42%), age (by 1.4%/year), electrocardiographic left ventricular mass (by 15%/mV) and sitting systolic blood pressure (by 0.9%/mmHg), but decreased with sitting pulse rate (by 1.9%/beat per min). An exaggerated orthostatic fall in diastolic blood pressure was 30% more likely in men; the likelihood increased with age (by 6.4%/year) and decreased with sitting diastolic blood pressure (by 6.6%/mmHg). CONCLUSION: An exaggerated orthostatic blood pressure fall in older patients with isolated systolic hypertension is associated mainly with gender, age and blood pressure level. Previous antihypertensive treatment, a lower pulse rate and a lower electrocardiographic left ventricular mass were also associated with an exaggerated orthostatic fall in systolic blood pressure.

Age Factors↗
PubMed2007

Systolic hypertension in adult Nigerians with hypertension.

OBJECTIVE: To determine the prevalence of both systolic and diastolic hypertensions in relation to age and their impacts on target organ among adult Nigerians with hypertension. DESIGN: Observational study. PLACE AND DURATION OF STUDY: The Cardiovascular Clinic of the University of Ilorin Teaching Hospital, Nigeria, from July 2002 to June 2003. PATIENTS AND METHODS: Newly diagnosed adult hypertensives, with blood pressure >or= 140/90mmHg, taken twice with mercury column sphygmomanometer at 3 weeks interval, were studied. The total number of hypertensive patients treated over this period was also taken into consideration. The newly diagnosed hypertensives were classified using JNC VI classification. The frequency of occurrence of target organ damage such as Left Ventricular Hypertrophy (LVH), heart failure, renal impairment etc. was charted according to systolic and or diastolic pressures. The occurrence of systolic or diastolic blood pressure was also related with the age of the patients. Blood metabolic parameters were compared in both systolic and diastolic blood pressures for their possible contributory role. RESULTS: Two thousand seven hundred and ninety-two adult hypertensive patients were managed over the study period. Of them, 218 (7.8%) were newly diagnosed and studied. There were 94 males and 124 females. Seventy-seven (35.3%) were aged 60 years and above with equal frequency in the gender. One hundred and seventy-eight (81.7%) cases had combined systolic and diastolic pressures. Twenty-nine (13.3%) patients had systolic hypertension. Twenty-five (86.2%) of these 29 were aged 50 years and above and 20 (69.0%) were aged 60 years and above. Eleven (5.0%) patients had isolated diastolic hypertension and they were all in the age bracket 40-49 years. Systolic blood pressure was found to be rising with advancing age while diastolic blood pressure peaked at mid 40's and declined. Target organ damage occurred more frequently with systolic hypertension and advancing age than with diastolic hypertension. CONCLUSION: Systolic hypertension occurred more frequently in this series of adult Nigerians with hypertension. It was higher with advancing age and associated with more target organ damage than the diastolic hypertension.

Adult↗
PubMed2005

Assessment of left ventricular longitudinal regional myocardial systolic function by strain imaging echocardiography in patients with hypertrophic cardiomyopathy.

To assess the left ventricular longitudinal regional myocardial systolic function by strain imaging (SI) echocardiography and to study the relationship between regional myocardial systolic function and left ventricular structure in patients with hypertrophic cardiomyopathy (HCM). SI echocardiography were performed in 18 patients with HCM and 17 healthy subjects. For each wall, regional myocardial systolic strain was analyzed at the basal, mid, and apical level respectively. And the peak systolic strain was measured. Our results showed that the patients with HCM had reduced peak systolic strain at almost each segment of different walls when compared with healthy subjects. There was significant correlation between the mid-septum peak systolic strain and the thickness of IVS, so was the correlation between the mid-septum peak systolic strain and the IVS to LVPW thickness ratio. This study demonstrated that the left ventricular longitudinal regional myocardial systolic function was abnormal in HCM, and this kind of abnormalities existed extensively in hypertrophic and non-hypertrophic cardiac segments. The degrees of left ventricle hypertrophy and asymmetry are related to the myocardial regional systolic function in HCM.

Adult↗
PubMed1983

Atrial systole and left ventricular filling in hypertrophic cardiomyopathy: effect of verapamil.

Many patients with hypertrophic cardiomyopathy (HC) have impaired left ventricular (LV) rapid diastolic filling. To quantitate the contribution of atrial systole to LV filling, we used radionuclide angiography to study 30 normal volunteers and 42 patients with HC before and after oral administration of verapamil (320 to 560 mg/day). LV time-activity curves were constructed by combined forward and reverse gating from the R wave, and the onset of atrial systole was determined by the P-R interval. The percent of LV stroke volume filled during rapid diastolic filling and atrial systole was then computed. Peak LV filling rate during rapid diastolic filling was expressed in end-diastolic volume (EDV)/second. Peak rate of rapid diastolic filling was not different in normal patients and those with HC (3.3 +/- 0.6 versus 3.3 +/- 1.1 EDV/s) and was within the normal range in 34 patients with HC (81%). However, the contribution to LV filling volume by rapid diastolic filling was diminished in patients with HC (83 +/- 7% normal, 67 +/- 17% HC, p less than 0.001) and the contribution of atrial systole was increased (16 +/- 8% normal, 31 +/- 18% HC, p less than 0.001). LV filling volume during atrial systole was above the upper normal limit of 31% in 17 patients (40%), including 13 patients with a normal peak filling rate. After verapamil, peak filling rate increased (to 4.2 +/- 1.2 EDV/s, p less than 0.001), percent LV filling during rapid diastolic filling increased (to 83 +/- 7%, p less than 0.001), and percent LV filling during atrial systole decreased (to 16 +/- 9%, p less than 0.001). Percent LV filling volume during atrial systole was abnormal after verapamil in only 3 patients (7%). Hence, although the peak rate of rapid diastolic filling may be normal in patients with HC, the contribution to LV filling by rapid diastolic filling is reduced and that of atrial systole is thereby increased. Increased rate and magnitude of rapid diastolic filling during verapamil is associated with decrease and normalization of the contribution of atrial systole to LV filling. These data suggest that many patients with HC are at risk of hemodynamic decompensation with the onset of atrial fibrillation or other tachyarrhythmias and loss of the atrial contribution to LV filling. This risk may be reduced during verapamil therapy.

Adult↗