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Differential control of systolic and diastolic blood pressure in blacks with essential hypertension.

OBJECTIVE: The risk of cardiovascular and renal diseases has been shown to be higher for systolic blood pressure than diastolic blood pressure. The aim of this study was to assess the differential control of systolic and diastolic blood pressure in Nigerians with primary hypertension. DESIGN AND SETTING: This was a prospective observational study carried out at the Medical Outpatient Department of the State Hospital, Abeokuta, Nigeria. Ethical approval for the study was obtained from the ethical committee of the hospital. METHODOLOGY: The study population consisted of 185 consecutive patients (65 males, 120 females), aged 35-85 years with primary hypertension who had been on drugs one- to 25 years prior to the onset of the study. Clinic blood pressure control was assessed during a year period. Six consecutive clinic blood pressure readings were recorded for each patient and the average calculated (systolic blood pressure and diastolic blood pressure separately). Patients were classified into subgroups based on the pattern of blood pressure control. RESULTS: Clinic systolic blood pressure and diastolic blood pressure was controlled in 58 patients (31.4%). Systolic blood pressure control was less frequent than diastolic blood pressure control (35.7% versus 51.4%, p<0.05). Patients with uncontrolled systolic blood pressure were significantly older than patients with only uncontrolled diastolic blood pressure (66.7+/-7.4 versus 52.9+/-8.7 years, p<0.001). CONCLUSION: Systolic blood pressure is less frequently controlled than diastolic blood pressure in Nigerians treated for primary hypertension. This may increase the patient's risk of developing stroke, and cardiovascular and renal complications.

Adult↗

N-terminal-probrain natriuretic peptide and echocardiography in patients with systolic heart failure.

OBJECTIVE: To compare plasma N-terminal-probrain natriuretic peptide (NT-proBNP) levels with echocardiographic data in patients with systolic heart failure. METHODS: The study included 101 patients with systolic heart failure admitted to Al-Assad and Al-Moussa Hospitals, Damascus, Syria over a 10-month period from February 2004 to January 2005. The findings of the physical examination, electrocardiogram and blood pressure measurement were recorded along with the patient's history, risk factors, and drug treatment. We divided the patients into 4 groups according to the New York Heart Association classifications; class I=19, class II=22, class III=28, class IV=32 patients. We compared the values with 21 age-matched controls with no heart diseases (age range 49-80 years). During the study period, we carried out the plasma NT-proBNP levels and echocardiography of all patients and controls group. We used electroche-miluminescence immunoassay in measuring plasma NT-proBNP. Authorized physicians evaluated the ejection fraction (EF), systolic pulmonary pressure, and left ventricular end systolic diameter. Statistical analysis used was T-Distribution, and the difference considered to be significant at p<0.05. RESULTS: The plasma NT-proBNP levels in patients of asymptomatic heart failure class I (mean 1,038 pg/ml) were significantly higher (p<0.001) as compared with the controls (40.9 pg/ml), and it increased directly with the severity of heart failure. Plasma NT-proBNP levels were conversely correlated with the ejection fraction EF (r= -0.56, p<0.001) and it increased as the EF declined. There was a significant direct linear correlation between plasma NT-proBNP levels and the left ventricular end systolic diameter (r=0.57) and systolic pulmonary pressure r=0.54. CONCLUSION: The left ventricle releases the B-type natriuretic peptide in response to volume or pressure overload, its high level reflects the poor cardiac systolic function, which corresponds with the echocardiographic data.

Age Distribution↗

[Left ventricular systolic function in patients surgically treated for atrioventricular septal defect: echocardiographic assessment].

In order to assess the left ventricular systolic function we studied by echo 14 pts (8M, 6F) with complete atrioventricular septal defect (AVSD) who had undergone surgical repair. Mean age was 20.30 +/- 24.63 months, with a follow-up of 52.85 +/- 19.11%; in 6 pts Down syndrome was associated. Particularly, we tried to determine whether the following factors might affect the post-operative left ventricular systolic function: a) Down syndrome; b) residual mild mitral regurgitation; c) age of the surgical repair; d) length of the follow-up. As load-independent indexes of contractility, the left ventricular end systolic stress (LVESS)-circumferential fibre shortening velocity normalized for heart rate (VCFc) relationship and the LVESS/end systolic volume index (ESVI) ratio were chosen. All pts showed normal (mean +/- 2 standard deviations) or slightly higher values of LVESS/VCFc relationship; significantly, the only two pts with lower values had later undergone surgical repair. LVESS/ESVI ratio confirmed an inverse relationship between systolic function and age of the surgical correction (r = -0.75); no other factors (Down syndrome, residual mild mitral regurgitation, length of the follow-up) showed a significant correlation with the post-operative left ventricular systolic function. In conclusion, in our limited population, the age of the surgical repair appears to be the main factor affecting the post surgical left ventricular systolic function in pts with complete AVSD.

Child↗

[Echocardiographic detection of adriamycin cardiotoxicity. Study of the relationship between the shortening fraction-constraint and the systolic shortening fraction-diameter of the left ventricle].

Cardiotoxicity is the main obstacle to the use of high-dosage adriamycin in chemotherapy. It is difficult to decide whether or not treatment should be continued when the cardiac function -- irrespective of the method by which it is evaluated -- is at the lower limit of normality. Some authors consider that chemotherapy can be pursued as long as the shortening fraction of the echocardiographic diameter remains within normal limits in relation to the end-systolic constraint. We have established the limits of normality of this relationship before chemotherapy in 53 patients with normal cardiovascular system. We conclude that the end-systolic constraint essentially depends on the end-systolic diameter, so that the results provided by the study of the shortening fraction end-systolic constraint relationship are qualitatively the same as those of the shortening fraction-end-systolic diameter relationship, which is much easier to obtain. It seems to us that the criteria of cardiotoxicity after administration of adriamycin 300 mg/m2 are: (1) shortening fraction lower than 25 p. 100; (2) ventricular dilatation (end-systolic diameter greater than 40 mm) without associated valve disease; (3) reduction of the shortening fraction (whatever its value) in relation to the end-systolic diameter by more than 2 standard deviations on the regression slope of the correlation; (4) more than 25 p. 100 reduction of the shortening fraction after administration of adriamycin 300 mg/m2, betraying a high sensitivity to the cardiotoxic effects of the drug. Such individual sensitivity, studied in 25 patients, seemed to vary widely from one subject to another and to be independent of the initial status.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Quantitative evaluation of left ventricular systolic function using bidimensional echocardiography: comparison with cineangiography].

The aim of the study was to compare the evaluation of the left ventricular systolic function performed both by angiography and 2D-echocardiography on 80 subjects (31 with coronary artery disease, 18 with left ventricular volume overload, 10 with left ventricular pressure overload, 14 with mitral valve disease and 7 normal controls). The 2D-echocardiograms of the left ventricle with simultaneous measurement of the right arm systolic blood pressure was performed within 24 hours of the angiographic examination. The following parameters were obtained using the two methods: end-diastolic volume index, end-systolic volume index, ejection fraction, left ventricular mass index, mass/volume ratio, end-systolic circumferential stress, contractility expressed as end-systolic circumferential stress/end-systolic volume ratio; the end-systolic circumferential stress/ejection fraction ratio was calculated only by 2D-echocardiography. The afterload and contractility were not calculated in subjects with coronary artery disease and left ventricular outflow gradient. No statistically significant differences were shown between the two methods, except a slight under-estimation by echocardiography of the angiographic end-diastolic volume index (93.1 +/- 38.9 ml/m2 vs 115 +/- 39.9 ml/m2; p less than 0.01) and over-estimation of the mass/volume ratio (1.38 +/- 0.33 g/ml vs 1.2 +/- 0.44 g/ml; p less than 0.01) was shown between the two methods for all parameters. A depressed contractile state was also demonstrated by the end-systolic circumferential stress/ejection fraction ratio. The inter and intraobserver variability was 6.6 +/- 4.4% (range 0.16%) and 4.2 +/- 3% (range 1.11%) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[The end-systolic pressure-volume relationship in the assessment of left ventricular function (author's transl)].

This investigation was undertaken to determine whether the left ventricular (LV) end-systolic pressure and end-systolic volume, as measured under clinical conditions, are linearly correlated and whether the slope of the end-systolic pressure-volume relationship (P-Ves) is a meaningful parameter in the assessment of left ventricular function. The studies were performed in twelve patients (eleven with coronary artery disease and one with congestive cardiomyopathy) during which autonomic reflex responses were minimized by propranolol (0.15 mg/kg i.v.) and atropine (1 mg i.v.). Three left ventricular angiograms (at rest, after 10 mg isosorbide dinitrate and during an infusion of 2 mg/min methoxamine) were obtained from which the three respective P-Ves data points were calculated and subjected to linear regression analysis (r greater than or equal to 0.96). The slope k of the linear P-Ves relation correlated most closely with the resting ejection fraction (EF) as an exponential function (r = 0.94). The end-systolic pressure could be interchanged with the peak systolic pressure which is more easily obtained. The theoretical end-systolic volume at end-systolic pressure = 0 (V0) was not related to the resting ejection fraction. Post-extrasystolic potentiation, resulting in an acute inotropic incrementation, shifted the P-Ves toward similar volumes and steepened its slope.

Atropine↗

Peak systolic pressure/end-systolic volume ratio, a load-independent measure of ventricular function, is reversibly decreased in human septic shock.

OBJECTIVE: To evaluate left ventricular performance in patients with septic shock, using a load-independent measure of left ventricular systolic function, the peak systolic pressure/end-systolic volume index ratio. SETTING: National Institutes of Health research facility. DESIGN: Prospective study with retrospective analysis of data. PATIENTS: Twenty-seven patients with septic shock, 13 critically ill, nonseptic control patients, and nine normal volunteers. MEASUREMENTS: Hemodynamic measurements from indwelling arterial and pulmonary artery catheters and radionuclide-determined ejection fraction measurements. These data were used to calculate the peak systolic pressure/end-systolic volume index ratio in each patient group. The survivors and nonsurvivors of septic shock were evaluated on admission to the intensive care unit and at recovery in the survivors or within 24 hrs of death in the nonsurvivors. The ratio in each group was compared with the ratio in the critically ill, nonseptic patients and the normal volunteers. MAIN RESULTS: Both survivors and nonsurvivors of septic shock had a decreased peak systolic pressure/end-systolic volume index ratio (1.2 +/- 0.1 and 1.7 +/- 0.2 mm Hg/mL/m2, respectively) compared with critically ill, nonseptic patients (3.5 +/- 0.7 mm Hg/mL/m2; both p < .05) and normal volunteers (4.3 +/- 0.4 mm Hg/mL/m2; both p < .05). The differences between the groups were highly significant (p < .001) by analysis of variance. The survivors had a lower initial peak systolic pressure/end-systolic volume index ratio than the nonsurvivors (p < .05). In the survivors, the peak systolic pressure/end-systolic volume index ratio increased significantly (p < .05) with recovery to 2.4 +/- 0.3 mm Hg/mL/m2. Serial determinations of peak systolic pressure/end-systolic volume index ratio in the nonsurvivors did not show any significant change. CONCLUSIONS: This study confirms that survivors and nonsurvivors of septic shock have significant depression of myocardial performance as measured by a load-independent technique. Survivors have greater depression of myocardial performance than nonsurvivors, and, with recovery, the ventricular performance in survivors increases toward normal values.

Adolescent↗

Hydrotherapy of patients with intermittent claudication: a novel approach to improve systolic ankle pressure and reduce symptoms.

OBJECTIVE: To study the effects of alternating cold and hot water therapy on walking ability and systolic blood pressure in claudicants. EXPERIMENTAL DESIGN: A prospective case study with repeated measurements before and 1, 4 and 12 months after treatment. The systolic blood pressure levels were measured with an occlusion cuff for brachial and ankle and with a strain gauge for the first toe. STUDY POPULATION: Twenty consecutively included patients, 11 women and 9 men; mean age 73.9 yrs, with intermittent claudication according to clinical examination and ankle-arm systolic blood pressure (AAI) below 0.90. INTERVENTION: Alternate hot and cold hydrotherapy of the legs were given at ten 25-minute treatments during a three-week period. The outcome measures were maximal walking ability (MW), walking ability before pain (PW) and systolic blood pressures of toe, ankle, arm and AAI. RESULTS: Fourteen patients (70%) reported reduced pain after treatment and their PW increased from 134 +/- 29 m to 415 +/- 119 m 12 months later (p < 0.05) and the MW in the total group increased form 348 +/- 75 m to 523 +/- 103 m. Systolic blood pressure increased in right ankle and toe one month after treatment in the total group. Among those who reported improved walking ability one year after treatment, systolic blood pressure in both right and left ankles and toes increased; e.g. right toe increasing from 72 +/- 7 to 86 +/- 2 (p < 0.001). Improvements of systolic blood pressure in left and right leg and changes of walking ability were correlated, in the order of 0.60 to 0.81, p < 0.05. CONCLUSIONS: Showering the legs of claudicants improved walking ability and blood pressures which sustained up to 1-year later. This therapy might be an additional alternative to conservative treatment of intermittent claudication.

Aged↗

[Atrial filling fraction predicts left ventricular systolic function after myocardial infarction: pre-discharge echocardiographic evaluation].

Aim of the study was to examine the relation between Doppler-derived indices of left ventricular diastolic and systolic function early after myocardial infarction. Fifty-three patients (31 males, 22 females) recovering from acute myocardial infarction underwent predischarge Doppler echocardiographic examination. Patients with age > 70 years, previous myocardial infarction, more than mild mitral and aortic regurgitation, mitral and aortic stenosis were excluded. Twenty-two healthy subjects (13 males; 9 females) free of coronary risk factors were selected as the control group. Both end-diastolic and end-systolic volumes and ejection fraction were measured by two-dimensional echocardiography. Pulsed Doppler was used to evaluate mitral inflow and left ventricular outflow velocity patterns. The following indices were measured: peak velocity of early (E) and late (A) flows, ratio of E/A peak velocities, ratio of early to late time velocity integrals, atrial filling fraction (time velocity integral A / time velocity integral of flow during total diastole) and deceleration time of E wave for mitral inflow; peak and time-velocity integral for left ventricular outflow. Stroke volume and cardiac output were obtained by pulsed Doppler using the left ventricular outflow method. The two groups were comparable for age, with blood pressure (p < 0.05) and heart rate (p < 0.01) reduced in myocardial infarction patients. Both end-diastolic and end-systolic volumes were significantly higher (both p < 0.0001) and ejection fraction (p < 0.0001) lower after myocardial infarction. Also stroke volume and cardiac output (both p < 0.0001) were reduced in myocardial infarction patients. No significant difference in Doppler indices of diastolic function was observed between the two groups, except for shortened deceleration time (p < 0.0001) in myocardial infarction patients. Multilinear regression analyses were performed separately into the two groups to identify determinants of left ventricular systolic function. After adjusting for age, heart rate, systolic blood pressure and both end-diastolic and end-systolic volumes, atrial filling fraction was an independent predictor of stroke volume, with a direct relation (beta coefficient = 0.53, p < 0.001), in myocardial infarction patients but not in health subjects. In conclusion, our study confirms the pseudonormalization of diastolic pattern after myocardial infarction. The direct relation between atrial filling fraction and stroke volume indicates the importance of atrial contribution to maintain an adequate systolic performance in patients with myocardial infarction.

Atrial Function, Right↗

Continuing dilemmas concerning aortic valve replacement in patients with advanced left ventricular systolic dysfunction.

Aortic valve replacement in patients with aortic stenosis or aortic regurgitation who have severe left ventricular (LV) systolic dysfunction continues to be associated with a high mortality risk despite surgical, cardiological and anesthetic improvements over time. As a result of earlier surgical referral, however, fewer patients with aortic regurgitation (AR) and advanced LV failure present for operation today. Favorable operative and long-term results, and data demonstrating recovery of LV systolic function if patients are referred prior to the onset of systolic dysfunction have largely solved this problem in the context of AR. On the other hand, patients with critical aortic stenosis (AS) and severe LV systolic dysfunction constitute a more heterogeneous and even more challenging group. On one side of the continuum, patients with truly critical AS and low ejection fraction due to LV 'afterload mismatch' (depressed ejection performance resulting from excessively high systolic LV wall stress secondary to a very tight valve) generally respond well to aortic valve replacement, which immediately normalizes LV afterload. Conversely, patients with 'critical' aortic stenosis and advanced LV systolic dysfunction who present with a low transvalvular gradient and cardiac output constitute a subgroup at high operative risk, which also has a suboptimal prognosis after aortic valve replacement. This clinical situation has been termed the 'Gorlin Conundrum', and is punctuated by a low mean transvalvular gradient and low flow. The reason for the low transvalvular gradient is not always known, but can be secondary to some type of coexistent cardiomyopathy. Patients with only mild pathologic aortic valve sclerosis/stenosis and markedly depressed LV systolic function are frequently judged to have 'critical' aortic stenosis (AVA < 0.8 cm2 or AVAI < 0.4 cm2/m2) due to inherent flaws in the Gorlin equation and limitations of the Doppler continuity equation. Although alternative diagnostic techniques have been proposed, e.g. aortic valve resistance, stroke work loss, none has yet proven to be totally reliable. The suboptimal results of aortic valve replacement in low-gradient AS patients underscore our difficulty in currently predicting which patients will benefit from valve replacement. Newer diagnostic techniques, including dobutamine echocardiography, and novel new findings regarding the basic molecular mechanisms responsible for contractile dysfunction in pressure overload hypertrophy may ultimately improve the results of surgical treatment in these patients.

Aortic Valve Insufficiency↗

[Estimation of left ventricular systolic function based on the electrocardiograms in cases with left bundle branch block].

The electrocardiographic features indicating left ventricular dysfunction were studied in 32 consecutive patients having left bundle branch block including 10 with idiopathic genesis without significant underlying disease, 6 with dilated cardiomyopathy, 8 with old myocardial infarction, and 8 with hypertensive heart disease. The patients were divided into two groups; those with favorable left ventricular systolic function and those with poor left ventricular systolic function evaluated by using non-invasive methods. Electrocardiographic findings were compared between these two groups. Ten patients had favorable and 22 poor left ventricular systolic function. One or more of the following electrocardiographic findings were observed in the poor group, but none in the favorable group: low voltage in the limb leads, prolonged intraventricular conduction (QRS duration wider than 0.17 sec), transitional zone between V5 and V6, depression of the ST-J point by more than 0.2 mV in V6, reverse progression of the R wave in V1-V5, marked left axis deviation (axis beyond: 30 degrees), left atrial overload (positive Morris index), PQ prolongation, and abnormal Q waves in I, aVL, V6. No significant differences in the distribution of these findings was observed in any of the underlying diseases. The clinical background of patients with left bundle branch block who had no significant underlying disease showed favorable left ventricular systolic function except the patients above 80 years of age, who showed poor left ventricular systolic function. In contrast, patients with underlying mild hypertensive heart disease may have a favorable left ventricular systolic function. Thus, left ventricular systolic function in patients with left bundle branch block may be suspected by observing these electrocardiographic findings.

Aged↗

Subgroup and per-protocol analysis of the randomized European Trial on Isolated Systolic Hypertension in the Elderly.

BACKGROUND: In 1989, the European Working Party on High Blood Pressure in the Elderly started the double-blind, placebo-controlled, Systolic Hypertension in Europe Trial to test the hypothesis that antihypertensive drug treatment would reduce the incidence of fatal and nonfatal stroke in older patients with isolated systolic hypertension. This report addresses whether the benefit of antihypertensive treatment varied according to sex, previous cardiovascular complications, age, initial blood pressure (BP), and smoking or drinking habits in an intention-to-treat analysis and explores whether the morbidity and mortality results were consistent in a per-protocol analysis. METHODS: After stratification for center, sex, and cardiovascular complications, 4695 patients 60 years of age or older with a systolic BP of 160 to 219 mm Hg and diastolic BP less than 95 mm Hg were randomized. Active treatment consisted of nitrendipine (10-40 mg/d), with the possible addition of enalapril maleate (5-20 mg/d) and/or hydrochlorothiazide (12.5-25 mg/d), titrated or combined to reduce the sitting systolic BP by at least 20 mm Hg, to below 150 mm Hg. In the control group, matching placebo tablets were employed similarly. RESULTS: In the intention-to-treat analysis, male sex, previous cardiovascular complications, older age, higher systolic BP, and smoking at randomization were positively and independently correlated with cardiovascular risk. Furthermore, for total (P = .009) and cardiovascular (P = .09) mortality, the benefit of antihypertensive drug treatment weakened with advancing age; for total mortality (P = .05), the benefit increased with higher systolic BP at entry, while for fatal and nonfatal stroke (P = .01), it was most evident in nonsmokers (92.5% of all patients). In the perprotocol analysis, active treatment reduced total mortality by 24% (P = .05), reduced all fatal and nonfatal cardiovascular end points by 32% (P<.001), reduced all strokes by 44% (P = .004), reduced nonfatal strokes by 48% (P = .005), and reduced all cardiac end points, including sudden death, by 26% (P = .05). CONCLUSIONS: In elderly patients with isolated systolic hypertension, stepwise antihypertensive drug treatment, starting with the dihydropyridine calcium channel blocker nitrendipine, improves prognosis. The per-protocol analysis suggested that treating 1000 patients for 5 years would prevent 24 deaths, 54 major cardiovascular end points, 29 strokes, or 25 cardiac end points. The effects of antihypertensive drug treatment on total and cardiovascular mortality may be attenuated in very old patients.

Aged↗

[The effect of sudden changes in the stimulation rate of the heart on peak systolic pressure (author's transl)].

The changes in systolic pressure were studied in 48 patients during artificially (by electrical stimulation) induced sudden increases and consecutive decreases in heart rate. Various patterns could be separated respective to phase A (sudden switch from low (80-120 impulses/min) to higher heart rate (140-180 impulses/min)) and to phase B (sudden switch-back from high to lower (control) beating rate): AI) The systolic peak-pressure of the first contraction after the shortened stimulation interval is very low and often stays ineffective (below the aortic opening pressure). The second contraction develops already a higher pressure than the first one, during the consecutive beats the systolic pressure increases gradually until a new steady state is reached, which is usually lower than the systolic pressure during the foregoing lower beating rate. Sometimes however it can be equal or even higher. Accordingly after an elevation of heart rate arterial mean pressure can drop, stay constant or increase. AII) The systolic peak-pressure of the first contraction after the shortened stimulation interval stays relatively high and drops continuously with the succeeding contractions until a new steady state is reached according to the higher heart rate, it is however always lower than the one at a lower stimulation rate. Therefore arterial mean pressure is always decreased. AIII) Finally we observed changes in arterial systolic pressure in some patients that could not be grouped according to one or to the other pattern described above.- BI) The systolic peak of the first contraction after the switch-back from the high to the lower (control) rate is much higher than that of the last at the higher rate. The peak pressures of the consecutive contractions are then dropping continuously to the new steady-state, that can be higher, equal or lower than that at the higher stimulation rate. BII) ....

Adolescent↗

Continuous estimation of systolic blood pressure using the pulse arrival time and intermittent calibration.

A continuous noninvasive method of systolic blood pressure estimation is described. Systolic blood pressure is estimated by combining two separately obtained components: a higher frequency component obtained by extracting a specific frequency band of pulse arrival time and a lower frequency component obtained from the intermittently acquired systolic blood pressure measurements with an auscultatory or oscillometric system. The pulse arrival time was determined by the time interval from QRS apex in electrocardiogram to the onset of photoplethysmogram in a fingertip beat-by-beat via an oximetric sensor. The method was examined in 20 patients during cardiovascular surgery. The estimated values of systolic blood pressure were compared with those measured invasively using a radial arterial catheter. The results showed that the correlation coefficients between estimated values and invasively obtained systolic blood pressure reached 0.97 +/- 0.02 (mean +/- SD), and the error remained within +/- 10% in 97.8% of the monitoring period. By using a system with automatic cuff inflation and deflation to acquire intermittent systolic blood pressure values, this method can be applicable for the continuous noninvasive monitoring of systolic blood pressure.

Adolescent↗

Detection of left ventricle systolic dysfunction from shape deformity.

Coronary artery disease producing ischemic cardiomyopathy is the most frequent cause of left ventricular systolic dysfunction. Non-ischemic cardiomyopathies can also produce systolic dysfunction; they may be inherited as genetic disorders or occur sporadically. These coronary injuries have repercussions on the left ventricle producing changes on wall contractility, the shape of the cavity and also changes on ventricular function. This study is focused on the 2D echocardiograms of the left ventricle. Apical two chamber and four chamber view recordings were performed on normal and systolic dysfunction subjects. Individual frames were extracted for at least five cardiac cycles. After pre-processing these images, segmentation of the left ventricle was performed by Fuzzy systems. Then the volumes were measured by single and biplane methods along with the perimeter, short axis length and long axis length in each frame, from which the two indices Sphericity Index (SI) and Normalized Eccentricity Index (NEI) was determined. It was found that the diastolic phase is short in the case of systolic dysfunction, and its volume variation is not uniform as in the normal case. Also, in the case of systolic dysfunction, the span of either the long or short axis length variation is less than 0.5 cm. This depicts that akinesis is in the corresponding direction; the value of SI is less than 2 for systolic dysfunction. A sharp peak is seen at each systole point in the NEI plot and also its variation is smooth in subjects having LVEF > 45%, which is not the case for dysfunction.

Algorithms↗

Exercise capacity in young adults with hypertension and systolic blood pressure difference between right arm and leg after repair of coarctation of the aorta.

Coarctation of the aorta represents 5-7% of congenital heart defects. Symptoms and prognosis depend on the degree of stenosis, age at surgery, surgical method and the presence of other heart defects. Postoperative complications are hypertension, restenosis and an abnormal blood pressure response during exercise. This study includes 41 patients, 15-40 years old, operated in the period 1975-1996. All were exercised on a treadmill until maximal oxygen consumption was achieved. Blood pressure was measured in the right arm and leg before and immediately after exercise, and in the right arm during exercise. Oxygen consumption was monitored and we defined an aerobic phase, an isocapnic buffering phase and a hypocapnic hyperventilation phase. The resting systolic blood pressure correlates with the resting systolic blood pressure difference between right arm and leg. A resting systolic blood pressure difference between the right arm and leg of 0.13 kPa (1 mmHg) to 2.67 kPa (20 mmHg) corresponds with a slight increase in resting systolic blood pressure. This rise in blood pressure increases the aerobic phase of the exercise test, helping the patients to achieve higher maximal oxygen consumption. A resting systolic blood pressure difference of more than 2.67 kPa (20 mmHg) corresponds with severe hypertension and causes reduction in the aerobic phase and maximal oxygen consumption. Resting systolic blood pressure and resting systolic blood pressure difference between the right arm and leg are not indicators for blood pressure response during exercise. Exercise testing is important to reveal exercise-induced hypertension and to monitor changes in transition from aerobic to anaerobic exercise and limitation to exercise capacity.

Adolescent↗

Late systolic indices of ventricular function: noninvasive derivation in congestive heart failure.

The slopes of end-systolic pressure/end-systolic dimension and volume relations have been found to be relatively load-independent indices of left ventricular contractility. Noninvasive determination of these relationships has been performed in normal subjects and has been found to reflect baseline and drug-induced changes in ventricular contractility. Three late systolic indices of ventricular contractility were noninvasively determined in subjects with chronic congestive heart failure to determine the feasibility of the method and to assess the linearity and slopes of the relationships in this population. All relations were linear with individual correlation coefficients ranging from 0.86 to 0.99. The mean +/- SD slope was 42.8 +/- 26.4 mm Hg/cm for the end-systolic pressure-dimension relation, 0.59 +/- .42 mm Hg/ml for the end-systolic pressure-volume relation, and 48.7 +/- 32.2 mm Hg/cm for the peak systolic pressure-end-systolic dimension relation. All slopes were markedly reduced compared to those reported in normal individuals. The relative degree of depression was greater for the pressure-volume slope than for the pressure-dimension slope, which is explained by the relationship between volume and dimension in dilated ventricles. These data indicate that measurement of late systolic indices of ventricular contractility by this noninvasive technique is feasible in subjects with congestive heart failure and yields reduced slopes consistent with the diminished contractile state of this population. Pressure-volume rather than pressure-dimension relations may more accurately reflect inotropic state in dilated ventricles.

Cardiomyopathy, Dilated↗

Usefulness of systolic time intervals in coronary artery disease.

This review summarizes current knowledge concerning the value of systolic time intervals in coronary artery disease. Although the usual pattern of prolongation of the preejection period (PEP) and shortening of the left ventricular ejection time (LVET) characteristic of left ventricular failure is seen in acute myocardial infarction, the systolic time intervals (as well as all other measures) are profoundly influenced by adrenergic hyperactivity characteristics of this disorder. Adrenergic stimulation normally shortens both the PEP and LVET indexes and decreases the PEP/LVET ratio. The degree of shortening of electromechanical systole (QS2) is directed related to the excessive adrenergic tone. Patients with the greatest systolic time interval abnormalities have a poorer prognosis, a greater incidence of congestive heart failure and more abnormalities of directly measured indexes of left ventricular performance. The systolic time intervals are useful for assessing left ventricular performance in chronic coronary artery disease as well. In chronic coronary artery disease the PEP/LVET ratio and angiographically determined left ventricular ejection fraction are closely correlated ( r = -0.76), but the level of this correlation is less than that in other forms of left ventricular disease. The left ventricular ejection time index is prolonged after exercise in patients with angina pectoris when compared with findings in normal subjects. Failure of the ischemic ventricle to respond to adrenergic stimulation is the most likely mechanism. Addition of the postexercise left ventricular ejection time to standard treadmill stress testing identifies a significant number of patients (23 percent) who would have had false negative results by electrocardiographic criteria alone. In addition, this index provides confirmatory evidence in those with apparently positive electrocardiographic test data. The systolic time intervals have been useful in assessing both medical and surgical therapy in coronary artery disease. The test can be performed repeatedly and provides a measure of both left ventricular performance and extent of adrenergic hyperactivity. Thus, evaluation of therapy represents the most useful future application of systolic time intervals.

Acute Disease↗