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PubMed2005

Association between intraventricular myocardial systolic dyssynchrony and ventricular arrhythmias in patients with hypertrophic cardiomyopathy.

BACKGROUND: The distribution and magnitude of left ventricular (LV) hypertrophy are not uniform in patients with hypertrophic cardiomyopathy (HCM), which results in regional heterogeneity of LV systolic and diastolic function. The aim of the study was to evaluate LV regional systolic asynchrony in patients with HCM by pulsed Doppler myocardial imaging (DMI). METHODS: We studied 35 HCM patients and 45 age- and sex-matched controls. By the use of DMI, the following five different basal myocardial segments were measured: systolic peak velocity (Sm); early- and late-diastolic peak velocities; pre-contraction time (Q-Sm) (from the beginning of Q-wave of ECG to the onset of Sm); intraventricular systolic delay (IntraV-Del) (difference of Q-Sm in different LV myocardial segments); interventricular delay (InterV-Del) (difference of Q-Sm between the most delayed LV segment and right ventricular lateral wall). RESULTS: DMI analysis showed in HCM lower myocardial systolic and early-diastolic peak velocities of all the analyzed segments. As for time intervals, controls showed homogeneous systolic activation of the ventricular walls. Conversely, HCM group, despite the absence of intraventricular conduction defects by surface ECG, showed significant both Inter- and IntraV-Del (P < 0.0001). Linear regression models pointed out independent positive associations of IntraV-Del with LV outflow gradient and septal wall thickness in HCM (P < 0.001). An IntraV-Del >30 msec well differentiated controls and HCM. In addition, an IntraV-Del > 45 msec (ROC curve) identified a subgroup of HCM patients with nonsustained ventricular tachycardia during Holter monitoring (90.9% sensitivity and 95.8% specificity). CONCLUSIONS: The impairment of intrarventricular systolic synchronicity is strongly related to increased septal thickness and LV outflow-tract gradient in HCM. DMI analysis may be able to select subgroups of HCM patients at an increased risk of ventricular tachyarrhythmias.

Adult↗
PubMed2003

Prevalence of impaired left ventricular systolic function and heart failure in a middle aged and elderly urban population segment of Copenhagen.

OBJECTIVE: To assess the prevalence of impaired left ventricular systolic function and manifest heart failure in a general population aged 50-89 years. DESIGN: In this cross sectional survey, participants filled in a heart failure questionnaire. ECG, blood tests, and echocardiography were performed. SETTING: The study population was recruited from general practitioners situated in the same urban area and examined in a university hospital in Copenhagen, Denmark. PARTICIPANTS: 764 participants (432 women and 332 men, median (SD) age 66 (11) years) participated. The study population was stratified to include a minimum of 150 persons in each age decade. MAIN OUTCOME MEASURES: Prevalence of impaired systolic function and manifest heart failure. RESULTS: The prevalence of systolic dysfunction (left ventricular ejection fraction < or = 40%) was more than twice as high among men (7.6%) as among women (2.6%). In the male population systolic heart failure (left ventricular ejection fraction < or = 40% and symptoms) was found in 1.8% of the 50-59 years age group and approximately doubled for each age decade to reach 13.9% in octogenarians. Among women systolic dysfunction increased from 0.8% to 4.3% in the same age groups. Asymptomatic cases accounted for 44.0% of all cases of systolic dysfunction in the male population and only 9.1% in the female population. CONCLUSIONS: In this age controlled population study impaired left ventricular systolic function and heart failure increased substantially with age and was more than twice as frequent among men as among women. Asymptomatic left ventricular dysfunction occurred more frequently in men than in women and was less prevalent with increasing age.

Age Factors↗
PubMed2001

Interrogation of the tricuspid annulus by Doppler tissue imaging in patients with chronic pulmonary hypertension: implications for the assessment of right-ventricular systolic and diastolic function.

BACKGROUND: Chronic pulmonary hypertension (CPHT) has a great impact on both right-ventricular (RV) systolic and diastolic properties and the assessment of those properties is not always feasible by traditional echocardiographic examination. Doppler tissue imaging (DTI) interrogation of the tricuspid annulus (TA) identifies the pattern of TA motion (TAM) and can help to assess RV function when other methods are not feasible. AIMS: To determine RV systolic and diastolic function in patients with CPHT using DTI parameters of the TA. METHODS: Eighty-seven patients with CPHT and 90 normal controls were studied. DTI parameters were measured including early diastolic, late diastolic and systolic velocities and time velocity integrals (TVI) of the TAM at both its lateral and medial aspect. RESULTS: Early diastolic and systolic velocities, the ratio of early to late diastolic velocities and TVI of TAM at both lateral and medial aspects were significantly decreased in patients with CPHT compared to controls. No significant differences were seen in late diastolic velocities and TVI in both groups. Systolic velocity of the TAM at both its lateral and medial aspects significantly correlated with RV systolic function as measured by fractional RV area change. CONCLUSIONS: DTI of the TAM can be used to assess RV systolic and diastolic properties in patients with CPHT.

Aged↗
PubMed1977

On the frequency of early systolic clicks in mitral valve prolapse.

Phonocardiography was performed in 74 patients with mitral valve prolapse. 24 patients had early systolic clicks (less than 80 msec from S1). Four of them had associated systolic murmurs. 30 patients had mid or late systolic clicks (greater than 80 msec from S1). A systolic murmur followed the click in 13 of these patients. Both an early and mid/late systolic click were noted in three patients. 17 patients did not have systolic murmurs. Seven patients had 'silent' mitral valve prolapse. In summary, early systolic clicks are common in mitral valve prolapse. In many instances the early click is not accompanied by a murmur. Echocardiography is recommended in patients with chest pain or arrhythmia of uncertain etiology, even if characteristic signs of mitral valve prolapse are absent.

Adolescent↗
PubMed1975

Volume ejected in early systole. A sensitive index of left ventricular performance in coronary artery disease.

Indices based on early systolic ejection rates are theoretically more sensitive to ventricular performance than indices based on the entire systolic ejection (SE) period (mean ejection phase indices-MEPI): mean systolic ejection rate (MSER), mean normalized systolic ejection rate (MNSER) and mean velocity of circumferential fiber shortening (MVcf). The volume ejected in early systole is an indicator of the early rate of ejection. Accordingly, ventricular volume changes were determined by ventriculographic analysis for each thrid of SE in ml/sec (SER), as normalized systolic ejection rate (NSER), and as percent of stroke volume (PSV). In ten normal controls all these indices were higher in the first third compared to the other thirds of SE. Seven patients with diffuse ventricular disease had depressed values in the first third of SE. Despite "normal ventriculograms and normal MEPI, eight patients with left anterior descending coronary artery stenoses (greater than 60%) also had definitely depressed ejection indices during first third of systole. Detailed wall motion analysis in this group showed anteroapical hypokinesis isolated to the first third of SE. These data show that indices based on early SER are more sensitive than MEPI (MVcf, MNSER) for detecting abnormalities in ventricular performance in coronary artery disease;

Adult↗
PubMed1991

Serial long-term assessment of the natural history of asymptomatic patients with chronic aortic regurgitation and normal left ventricular systolic function.

BACKGROUND: Many asymptomatic patients with aorta regurgitation and normal left ventricular systolic function remain clinically stable for many years, but others ultimately develop symptoms or left ventricular dysfunction and require operation. To identify indexes of left ventricular function predictive of symptomatic and functional deterioration during the long-term course of asymptomatic patients, we studied 104 asymptomatic patients with chronic severe aortic regurgitation and normal left ventricular ejection fraction at rest. METHODS AND RESULTS: Serial echocardiographic (average, 7.8 per patient) and radionuclide angiographic (average, 5.0 per patient) studies were obtained over a mean follow-up period of 8 years (range, 2-16 years). By Kaplan-Meier life table analysis, 58 +/- 9% of patients remained asymptomatic with normal ejection fraction at 11 years, an average attrition rate of less than 5% per year; two patients died suddenly, four developed asymptomatic left ventricular dysfunction, and 19 underwent operation because symptoms developed. By univariate Cox regression analysis, many variables on initial study were associated with death, ventricular dysfunction, or symptoms, including age, left ventricular end-systolic dimension and end-diastolic dimension, fractional shortening, and both rest and exercise ejection fraction (all p less than 0.001). The average rates of change of rest ejection fraction, fractional shortening, and end-systolic dimension were also associated with death or symptoms by univariate Cox analysis (all p less than 0.01). However, when all variables were included in a multivariate Cox analysis, only age (p less than 0.05), initial end-systolic dimension (p less than 0.001), and rate of change in end-systolic dimension and rest ejection fraction during serial studies (both p less than 0.05) predicted outcome. CONCLUSIONS: Thus, in addition to indexes of left ventricular function determined on initial evaluation, serial long-term changes in systolic function identify patients likely to develop symptoms and require operation. Patients have a higher risk of symptomatic deterioration if there is progressive change in end-systolic dimension or resting ejection fraction during the course of serial studies.

Adult↗
PubMed2005

Increased stroke volume and aortic stiffness contribute to isolated systolic hypertension in young adults.

Isolated systolic hypertension is a common condition in individuals aged older than 60 years. However, isolated systolic hypertension has also been described in young individuals, although the mechanisms are poorly understood. We hypothesized that in young adults, isolated systolic hypertension and essential hypertension have different hemodynamic mechanisms and the aim of this study was to test this hypothesis in a cohort of subjects from The ENIGMA Study. Peripheral and central blood pressure, aortic pulse wave velocity, cardiac output, stroke volume, and peripheral vascular resistance were determined in 1008 subjects, aged 17 to 27 years. Compared with normotensive subjects, those with isolated systolic hypertension had significantly higher peripheral, central, and mean blood pressure, aortic pulse wave velocity, cardiac output, and stroke volume (P<0.001 for all comparisons). However, there were no differences in pulse pressure amplification, heart rate, or peripheral vascular resistance between the two groups. Compared with subjects with essential hypertension, mean pressure, heart rate, and peripheral vascular resistance were all significantly lower in isolated systolic hypertensive subjects, but pulse pressure amplification, aortic pulse wave velocity, cardiac output, and stroke volume were higher (P<0.001 for all comparisons). We have demonstrated that in young adults, isolated systolic hypertension and essential hypertension arise from different hemodynamic mechanisms. Isolated systolic hypertension appears to result from an increased stroke volume and/or aortic stiffness, whereas the major hemodynamic abnormality underlying essential hypertension is an increased peripheral vascular resistance. Long-term follow-up of these individuals is now required to determine whether they are at increased risk compared with age-matched normotensive individuals.

Adolescent↗
PubMed2002

Outcome of congestive heart failure in elderly persons: influence of left ventricular systolic function. The Cardiovascular Health Study.

BACKGROUND: Most persons with congestive heart failure are elderly, and many elderly persons with congestive heart failure have normal left ventricular systolic function. OBJECTIVE: To evaluate the relationship between left ventricular systolic function and outcome of congestive heart failure in elderly persons. DESIGN: Population-based longitudinal study of coronary heart disease and stroke. SETTING: Four U.S. sites: Forsyth County, North Carolina; Sacramento County, California; Allegheny County, Pennsylvania; and Washington County, Maryland. PARTICIPANTS: 5888 persons who were at least 65 years of age and were recruited from the community. MEASUREMENTS: Total mortality and cardiovascular morbidity and mortality. RESULTS: Of 5532 participants, 269 (4.9%) had congestive heart failure. Among these, left ventricular function was normal in 63%, borderline decreased in 15%, and overtly impaired in 22%. The mortality rate was 25 deaths per 1000 person-years in the reference group (no congestive heart failure and normal left ventricular function at baseline); 154 deaths per 1000 person-years in participants with congestive heart failure and impaired left ventricular systolic function; 87 and 115 deaths per 1000 person-years in participants with congestive heart failure and normal or borderline systolic function, respectively; and 89 deaths per 1000 person-years in persons with impaired left ventricular function but no congestive heart failure. Although the risk for death from congestive heart failure was lower in persons with normal systolic function than in those with impaired function, more deaths were associated with normal systolic function because more persons with heart failure fall into this category. CONCLUSIONS: Community-dwelling elderly persons, especially those with impaired left ventricular function, have a substantial risk for death from congestive heart failure. However, more deaths occur from heart failure in persons with normal systolic function because left ventricular function is more often normal than impaired in elderly persons with heart failure.

Aged↗
PubMed2003

The epidemiology of "asymptomatic" left ventricular systolic dysfunction: implications for screening.

Congestive heart failure is a progressive disorder that is frequently preceded by asymptomatic left ventricular systolic dysfunction. We reviewed the epidemiology, diagnosis, and natural history of asymptomatic left ventricular systolic dysfunction and evaluated community-wide screening for this condition as a potential strategy to reduce the incidence of heart failure. Asymptomatic left ventricular systolic dysfunction has an estimated prevalence of 3% to 6%, and is at least as common in the community as systolic heart failure. Because it often occurs in the absence of known cardiovascular disease, this condition may go unrecognized and undertreated. In randomized trials, individuals with asymptomatic left ventricular systolic dysfunction have high rates of incident heart failure and death. However, little is known about the prognosis of individuals with this condition in the community, who have a substantially lower prevalence of myocardial infarction, have milder degrees of systolic dysfunction, and are older than patients enrolled in clinical trials. Current evidence is inadequate to support community-wide screening for asymptomatic left ventricular systolic dysfunction, either with echocardiography or with assays for natriuretic peptides. Given the increasing prevalence of heart failure, additional studies are needed to develop effective strategies to detect and optimally manage individuals with asymptomatic left ventricular dysfunction in the community.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1998

Conventional and ambulatory measurements of blood pressure in old patients with isolated systolic hypertension: baseline observations in the Syst-Eur trial.

OBJECTIVES: To compare clinic and am measurements of blood pressure in old patients with isolated systolic hypertension and their reproducibilities. PATIENTS: In total 610 patients aged >/= 60 years with isolated systolic hypertension detected by clinic measurement were monitored during the placebo run-in phase of the Syst-Eur trial. METHODS: The time-weighted 24 h blood pressure, clock-time day and night blood pressures, the cumulative-sum-derived crest and trough blood pressures and the high and low blood pressure levels according to the square-wave model were computed. The daily alteration between the high and low spans of blood pressure was quantified using the day-night difference, the cumulative-sum-derived magnitude of circadian alteration, the Fourier amplitude and the difference between the high and low blood pressure levels of the square-wave model. RESULTS: The daytime am systolic blood pressure was, on average, 21 mmHg lower than the clinic systolic blood pressure, whereas diastolic pressure was, on average, similar with both techniques of measurement. Clinic levels of blood pressure in the 141 patients who underwent repeat measurements and the parameters describing the difference between the daily high and low spans of blood pressure were equally reproducible. However, both were less reproducible than the ambulatory blood pressure levels. The reproducibility coefficients, expressed as percentages of near maximum variation, were 49 and 50% for the clinic systolic and diastolic blood pressures, 30 and 32% for the mean 24 h systolic and diastolic blood pressures and 45-55% for the parameters describing the daily alteration between the high and low spans of blood pressure. CONCLUSION: Values of blood pressure in old patients with isolated systolic hypertension were more reproducible for ambulatory than they were for clinic measurements. Levels in patients selected because they have a high clinic blood pressure may be substantially higher with conventional than they are with daytime ambulatory measurement. The prognostic significance of this difference for the present patients is currently under investigation.

Journal Article↗
PubMed1996

Conventional and ambulatory blood pressure measurement in older patients with isolated systolic hypertension:second progress report on the ambulatory blood pressure monitoring project in the Syst-Eur trial.

OBJECTIVES: To compare clinic and ambulatory blood pressure measurement and the reproducibility of these measurements in older patients with isolated systolic hypertension.PATIENTS: A total of 477 patients aged >/= 60 years with isolated systolic hypertension on clinic measurement were monitored during the placebo run-in phase of the Syst-Eur trial. METHODS: The time-weighted 24 h blood pressure, clock time day and night blood pressure, the cumulative sum-derived crest and trough blood pressure and the high and low blood pressure levels of the square-wave model were computed. The daily alteration between the high and low blood pressure spans was quantified using the clock time day-night difference, the cumulative sum-derived circadian alteration magnitude, the Fourier amplitude and the difference between the high and low blood pressure levels of the square-wave model. RESULTS: The daytime ambulatory systolic blood pressure was, on average, 21 mmHg lower than the clinic blood pressure, whereasthe diastolic blood pressure was, on average, similar with both techniques of measurement. In the 132 patients who underwent repeat measurements, clinic blood pressure levels and the parameters describing the difference betgween the daily high and low blood pressure spans were equally reproducible. However, both were less reproducible than the ambulatory blood pressure levels. The repeatability coefficients, expressed as percentages of near maximum variation, were 50 and 51% for the clinic systolic and diastolic blood pressures, 30 and 33% for the mean 24 h systolic and diastolic blood pressures and between 44 and 54% for the parameters describing the daily alteration between the high and low blood pressure spans. CONCLUSION: In older patients with isolated systolic hypertension, clinic and ambulatory systolic blood pressure may differ greatly; the prognostic significance of this difference remains to be elucidated. Furthermore, the level of blood pressure in these patients is more reproducible by ambulatory measurement than it is by clinic measurement.

Journal Article↗
PubMed1996

Comparison between office and ambulatory blood pressure in young and elderly subjects with isolated systolic hypertension.

BACKGROUND: It has been claimed that isolated systolic hypertension (ISH) in the elderly is not a sustained condition but a short-lasting increase in office systolic blood pressure magnified by arterial stiffness. DESIGN: Office and ambulatory blood pressures werecompared at baseline and after 3 months of observation of young and elderly subjects with ISH. METHODS: The study was carried out in 39 young (mean age 27.1+/-9.8 years) and 37 elderly patients (mean age 72.5+/-5.7 years). Office blood pressure was defined as the mean of six readings. All subjects underwent two non-invasive 24 h blood pressure monitorings performed 3 months apart and echocardiography (n = 50). RESULTS: The difference between office and mean 24 h systolic/diastolic blood pressure was 27.9/8.2 mmHg in the young and 18.9/6.9 mmHg in the elderly patients (P < 0.01 for systolic blood pressure). Twenty-four-hour (P < 0.001), daytime (P = 0.001) and night-time (P < 0.001) systolic blood pressures were higher in the elderly and the difference between daytime and night-time systolic blood pressure was greater in the young (P < 0.05). Office and ambulatory heart rates were significantly higher in the young subjects. The elderly patients showed a greater left ventricular wall thickness ( P = 0.005 for posterior wall; P < 0.005 for septum), relative wall thickness (P = 0.01) and left ventricular mass index (P = 0.001) and impaired left ventricular filling rate ( P = 0.05), whereas systolic performance and stroke volume were no different in the two groups. Due to the higher heart rate, cardiac output was greater in the young (P = 0.03). CONCLUSION: These data show that larger differences between office and ambulatory systolic blood pressure are not unique to elderly patients with ISH. Increased ambulatory blood pressure levels and a decreased nocturnal blood pressure fall were associated with left ventricular structural and functional abnormalities in the elderly subjects.

Journal Article↗
PubMed2000

The Effects of Candesartan Cilexetil in Isolated Systolic Hypertension: A Clinical Experience Trial.

An 8-week, multicenter, open-label, clinical experience trial evaluated the efficacy of candesartan cilexetil either alone (34%) or as add-on therapy (66%) in 1014 patients with untreated or uncontrolled isolated systolic hypertension defined as systolic blood pressure 140-179 mm Hg/diastolic less than 90 mm Hg. Candesartan cilexetil 16 mg once daily was given initially and was up-titrated to 32 mg once daily at week 2 or week 4 if systolic blood pressure remained at or above 140 mm Hg. Overall, candesartan cilexetil reduced both blood pressures by 16.5Â+/-0.6/4.5Â+/-0.2 mm Hg from 158Â+/-0.4/81Â+/-0.2 to 142Â+/-0.6/76Â+/-9.6 mm Hg with a control rate (systolic blood pressure less than 140 mm Hg) of 49%. Of the 492 (51%) patients remaining on the lower dose of candesartan cilexetil (40% as monotherapy; 60% as add-on), candesartan cilexetil 16 mg reduced blood pressure by 19.7Â+/-1.0/5.5Â+/-0.3 mm Hg and 62% of patients were controlled. For the 475 (49%) patients uncontrolled on candesartan cilexetil 16 mg and titrated to 32 mg (30% as monotherapy, 70% as add-on), the dose increase further reduced blood pressure by 8.9Â+/-0.4/3.8Â+/-0.1 mm Hg at week 8, and 36% of patients not responsive to the lower dose achieved blood pressure control on the higher dose. This dose response from candesartan cilexetil 16 mg to 32 mg was seen across age, sex, and race. Overall, tolerability was well maintained. Most adverse events were relatively infrequent, and only 8% withdrew due to adverse events; the most frequent adverse effects were dizziness (7%), headache (6%), and upper respiratory tract infection (5%). In conclusion, in this clinical experience trial for patients with isolated systolic hypertension, candesartan cilexetil 16 mg to 32 mg once daily produced a dose-related decrease in systolic blood pressure with a lesser decrease in diastolic blood pressure, resulting in a substantial decrease in pulse pressure. The dose response without dose dependent adverse effects was consistent across age, sex, and race, demonstrating that candesartan cilexetil is a therapeutic option for patients with isolated systolic hypertension. (c)2000 by Le Jacq Communications, Inc.

Journal Article↗
PubMed1994

Effects of age and isolated systolic hypertension on cardiovascular reflexes.

OBJECTIVES: Given the reported relationship between systolic hypertension and orthostatic hypotension in the elderly, to test the hypothesis that systolic hypertension causes impairment of the cardiovascular reflex function additional to the effects of age alone. DESIGN: Responses were compared in normotensive healthy young (n = 12) and elderly (n = 15) participants and elderly participants with disproportionate supine systolic hypertension (n = 11) using a baroreceptor-mediated stress (head-up tilt) and two non-baroreceptor-mediated stimuli (cold pressor test and isometric exercise). METHODS: Blood pressure and heart rate were measured by oscillometry before and during the three stress tests. Forearm blood flow was measured by venous occlusion plethysmography and pulse wave velocity (PWV) by Doppler ultrasound. RESULTS: Percentage changes in systolic/diastolic (SBP/DBP) blood pressure with head-up tilt were 0/+11, -3/0 and -6/+1 mmHg in the young and elderly normotensives and elderly systolic hypertensives, respectively. Both elderly groups had reduced DBP responses to tilt compared with the young (P < 0.01). All three groups had similar percentage changes in blood pressure responses to non-baroreflex-mediated stresses (cold pressor test: +10/+23, +11/+11, +10/+15; sustained isometric exercise: +18/+33, +22/+24, +13/+17 in the young and elderly normotensives and elderly systolic hypertensives, respectively). Aorto-iliac PWV adjusted for blood pressure was significantly higher in both elderly groups compared with the young (P < 0.01) but there was no difference between elderly normotensives and hypertensives. Unadjusted PWV was higher in elderly hypertensives than in elderly normotensives (P < 0.05). CONCLUSIONS: Compared with healthy young participants, both elderly groups had similarly attenuated blood pressure responses to tilt and reduced arterial compliance. Systolic hypertension is not associated with additional impairment of cardiovascular reflex function over and above the effects of age. The reported association between supine systolic hypertension and orthostatic hypotension does not appear to be a causative one.

Adolescent↗
PubMed1994

Spectral analysis of the systolic blood pressure signal in secondary hypertension: a method for the identification of phaeochromocytoma.

OBJECTIVE: To seek in hypertensive patients rhythmic variations of the systolic blood pressure signal obtained by ambulatory blood pressure monitoring of any inherent cycle of intermediate value between 1 and 24 h. DESIGN: Subjects (62 hypertensive, 39 normotensive) were evaluated by 24-h ambulatory blood pressure monitoring. The hypertensive group consisted of 48 patients with essential hypertension, nine with renovascular hypertension and five with phaeochromocytoma. The groups were matched for age and weight. METHODS: The ambulatory systolic blood pressure recording served as the input for a filtering procedure that rejected unacceptable values according to predetermined criteria. The whole-day systolic blood pressure series thus obtained were subjected to Fourier analysis to obtain a spectral analysis of daily systolic blood pressure fluctuations. Daily (first 12 h), nightly (second 12 h) and whole-day average systolic blood pressure values were calculated and compared for the various groups. RESULTS: The average nocturnal systolic blood pressure was found to be lower than its daily counterpart in the normal subjects and in the patients with essential hypertension, whereas in the patients with renovascular hypertension or phaeochromocytoma no such nocturnal decrease was found. The power spectrum of patients with phaeochromocytoma was statistically different from that of other aetiologies of hypertension. This was achieved due mainly to a statistically significant difference in the power spectrum integral over the low-frequency band (0-0.2 cycles/h) of the power spectrum of the 24-h systolic blood pressure signal. Resection of the phaeochromocytoma normalized the power spectrum as found by analysis of the postoperative ambulatory blood pressure monitoring data in two patients who underwent a repeat recording. CONCLUSIONS: The technique described enables the discrimination of patients with phaeochromocytoma as a cause of hypertension from other aetiologies of hypertension. Patients with renovascular hypertension could not be distinguished from those with essential hypertension on the basis of their power spectrum. However, this technique may prove to be a valuable modality for characterizing hypertensive patients of different aetiologies.

Activity Cycles↗
PubMed1993

Nonspecific systolic murmurs: an audit of the clinical value of echocardiography.

AIM: To evaluate the clinical use of echocardiography in patients with nonspecific systolic murmurs. METHODS: Analysis of request forms and echocardiogram reports in a consecutive series of scans done for patients with nonspecific systolic murmurs between 1984 and 1991. RESULTS: Normal cardiac structure and function were found in: (1) 62% of 565 studies done for patients with nonspecific systolic murmurs; (2) 96% of 69 scans in patients with clinical diagnosis of a benign murmur and (3) 93% of 45 pregnant women with nonspecific systolic murmurs. No echocardiographic abnormalities were detected in 76% of studies done for patients aged between 1 and 50 yr. Congenital heart disease was found in 39% of patients with nonspecific systolic murmurs aged between 0 and 1 yr. Mitral regurgitation was found in 33% and aortic valve disease in 22% of nonspecific systolic murmurs patients aged over 60 yr. CONCLUSIONS: Echocardiography rarely revealed significant abnormalities in the assessment of patients with nonspecific systolic murmurs aged between 1 and 50 yr, especially when the test was used to confirm the clinical suspicion that the heart was normal. Ultrasound scanning was useful in the assessment of nonspecific murmurs in patients aged 0-1 yr or over 50 yr, particularly those over 60 yr.

Adolescent↗
PubMedDate not supplied

Right ventricular systolic sub-periods. Normal values.

Right ventricular systolic sub-periods were examined in the group of 18 healthy subjects, basing on simultaneous electrocardiographic, phonocardiographic and pulmonary artery pressure tracings. The values established were compared with corresponding left ventricular systolic periods and correlated with selected hemodynamic parameters. Following mean values of the right ventricular systolic sub-periods were found: Q -- 1. sound interval = 0.051 sec., systolic time = 0.404 sec., ejection period = 0.319 sec., pre-ejection period = 0.085 sec., and isovolumetric contraction time = 0.034 sec. Both the right ventricular systolic and ejection periods were significantly longer than the corresponding left ventricular systolic ones. The ratio: right ventricular pre-ejection period to ejection period was lower than that calculated for the left ventricle. Both the right ventricular systolic and ejection periods negatively correlated with heart rate, whereas the ratio: right ventricular isovolumetric contraction time to ejection period depended on pulmonary artery pressure, pulmonary resistance and right ventricular work index.

Adolescent↗
PubMed1997

Inhaled nitric oxide reduction in systolic pulmonary artery pressure is less in patients with decreased left ventricular ejection fraction.

OBJECTIVE: To assess whether inhaled nitric oxide decreases pulmonary artery pressure in patients with depressed left ventricular ejection fraction. DESIGN: Randomized, blinded, crossover clinical trial. SETTING: Tertiary care university referral hospital. PATIENTS: Thirty-three patients with pulmonary hypertension and left ventricular dysfunction or valvular heart disease were recruited by convenience. INTERVENTIONS: Systolic pulmonary artery pressure was measured by Doppler echocardiography during randomized inhalation of either 20 ppm or 40 ppm nitric oxide in 30% oxygen as well as during control periods without nitric oxide. MAIN RESULTS: Systolic pulmonary artery pressure was significantly (P < 0.05) decreased with 20 ppm nitric oxide (53.4 +/- 13.9 mmHg) and 40 ppm nitric oxide (53.1 +/- 14.4 mmHg) compared with either initial control (55.8 +/- 15.3 mmHg) or terminal control (56.3 +/- 15.2 mmHg) values. The regression equation for the change in systolic pulmonary artery pressure (y) as predicted by the left ventricular ejection fraction (x) alone for 20 ppm nitric oxide was y = 13.8x-2.9; R2adj = 0.30, P < 0.0001. For 40 ppm nitric oxide alone, the regression equation was y = 16.3x-3.3; R2adj = 0.25, P < 0.0001. Left ventricular ejection fraction was the most explanatory independent variable in the multivariate equation for nitric oxide-induced change in systolic pulmonary artery pressure (R2 = 0.61, P = 0.0000). The change in systolic pulmonary artery pressure was -5.1 +/- 5.2 versus 0.8 +/- 4.9 mmHg (P < 0.0000) in patients with left ventricular ejection fractions greater than 0.25, and 0.25 or less, respectively. CONCLUSIONS: These data imply that in patients with left ventricular ejection fraction of 0.25 or less, nitric oxide may not decrease systolic pulmonary artery pressure. Nitric oxide inhalation may result in a paradoxical increase in systolic pulmonary artery pressure in patients with severely depressed left ventricular ejection fraction. This effect would significantly limit the therapeutic role of nitric oxide in patients with severe heart failure.

Administration, Inhalation↗