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Use of auscultation to follow patients with mitral systolic clicks and murmurs.

Mitral systolic clicks and murmurs together with associated symptoms constitute a major reason for cardiologic referral. Although echocardiography with Doppler study enables characterization of the mitral valve apparatus and quantification of regurgitation, its use has resulted in an overemphasis of the technical diagnosis of mitral valve prolapse and an undervaluation of diagnosis based on physical examination. To determine the clinical significance of an auscultatory classification of mitral systolic clicks with or without precordial systolic murmurs, 1 consultant's medical records of 291 patients with these signs were reviewed. Based on initial auscultatory findings, patients were divided into: (1) single or multiple apical systolic clicks with no murmur (n = 99); (2) single or multiple apical systolic clicks and a late systolic murmur (n = 129); and (3) single or multiple apical clicks and an apical pansystolic murmur or murmur beginning in the first half of systole (n = 63). The average duration of patient follow-up was 8 years (range 1 to 30). The prognosis was excellent for patients from all 3 classes. Two cardiac-related deaths occurred: 1 each from classes 1 and 2. Mitral valve surgery was performed in 3 class 2 patients (2%) and in 2 class 3 patients (3%). No patients developed endocarditis during follow-up. Palpitations, with varying anxiety overlay, constituted a major indication for cardiologic referral in all 3 classes. Auscultatory findings were valuable to the physician for explanation and relief of patient anxiety. For patient management, use of an auscultatory classification may be preferable to the technically generated term "mitral valve prolapse."

Adult↗

Determinants of the relation between systolic pressure and duration of isovolumic relaxation in the right ventricle.

Previous studies have suggested that right ventricular systolic pressure can be predicted from noninvasive estimates of the interval between pulmonary valve closure and tricuspid valve opening. To determine the basis for this relation, phonocardiograms and high fidelity right atrial and ventricular pressures were recorded in 29 patients with a right ventricular systolic pressure ranging from 20 to 149 mm Hg. In 22 patients with normal right atrial pressure (less than or equal to 8 mm Hg), both the time interval and the magnitude of pressure decrease from pulmonary valve closure to tricuspid valve opening were linearly related to systolic pressure (r = 0.89 and 0.96, respectively). Early pulmonary valve closure (decreased "hang-out" time) contributed to the greater magnitude of isovolumic pressure decrease at high systolic pressures, but correction for hang-out time did not eliminate the relation between systolic pressure and the pulmonary valve closure-tricuspid valve opening interval (n = 10). When patients with documented right coronary artery disease were excluded, the time constant for isovolumic pressure decrease also increased as a function of systolic pressure (r = 0.67, p less than 0.01, n = 24), suggesting impaired relaxation at high systolic pressures. However, the mean rate of pressure decrease (mean negative dP/dt) still was greater in patients with a high pressure because of the exponential nature of the isovolumic pressure-time relation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Linearity of the left ventricular end-systolic pressure-volume relation in patients with severe heart failure.

The left ventricular end-systolic pressure-volume relation is a relatively load-independent measure of left ventricular contractile function. Linearity of the relation derived from full left ventricular pressure-volume loops has not previously been demonstrated for patients with severe heart failure. Therefore, nine patients with markedly depressed left ventricular systolic function (ejection fraction 0.14 +/- 0.08) were studied with micromanometer left ventricular pressure measurement and simultaneous radionuclide ventriculography. Afterload was reduced with graded infusions of nitroprusside, allowing construction of pressure-volume loops under four afterload conditions in four patients and three afterload conditions in the other five patients. The end-systolic pressure-volume relation derived from the pressure-volume loops was found to be linear for the range of pressures and volumes examined, with correlation coefficients in individual patients ranging from 0.936 to 0.999 (mean 0.981). The mean slope of the relation (or end-systolic elastance) was 0.71 mm Hg/ml (range 0.42 to 1.52), and the extrapolated volume intercept at zero pressure was positive in all patients. An exponential relation between end-systolic elastance and ejection fraction was demonstrated for this group of patients. Approximations of end-systolic elastance obtained from measurements other than the full pressure-volume loops correlated variably with "true" elastance obtained from the pressure-volume loops. The relation between stroke work and end-diastolic volume was nonlinear in most patients. Thus, the end-systolic pressure-volume relation is linear in the "physiologic" range in patients with severe heart failure. This finding should permit construction of the relation from two loading conditions in clinical studies, facilitating its use as an index of contractile function in patients with heart failure.

Aged↗

Preload and flow propagation velocity: insight into patients with uremia and different left ventricular systolic function.

OBJECTIVES: The aim of this study was to investigate the changes of flow propagation velocity (FPV) after regular hemodialysis (H/D) in patient who were uremic with different baseline left ventricular (LV) functions. METHODS: In all, 24 patients with uremia and abnormal LV systolic function were enrolled in this study and 30 patients with uremia and normal LV systolic performance served as the control group. All patients had in sinus rhythm and underwent a comprehensive transthoracic echocardiographic examination and mitral FPV by color M-mode echocardiography before and after H/D. RESULTS: The decline in FPV before H/D was proportional to the decline in the baseline LV function, whereas FPV after H/D varied according to the LV ejection fraction. An obvious decrement of FPV for patients with normal LV systolic function was noted, but no obvious difference was seen for patients with abnormal LV systolic function. CONCLUSION: FPV was strongly preload dependent for patients with normal LV systolic function. It was not significantly influenced by preload for patients with abnormal LV systolic function. FPV is a relatively good diastolic parameter for investigating patients with LV systolic dysfunction.

Blood Flow Velocity↗

Combined right ventricular systolic and diastolic dysfunction represents a strong determinant of poor prognosis in patients with symptomatic heart failure.

BACKGROUND: The presence of right ventricular systolic dysfunction is known to significantly worsen prognosis of patients with heart failure. However, the prognostic impact of right ventricular diastolic dysfunction and of its combination with right ventricular systolic dysfunction and with other prognostic markers has not yet been systematically studied. The aim of this study was to assess the prognostic impact of combined right ventricular systolic and diastolic dysfunction in patients with symptomatic heart failure due to ischemic or idiopathic dilated cardiomyopathy. METHODS: The study included 177 consecutive patients with symptomatic heart failure (mean left ventricular ejection fraction of 23%). All patients underwent clinical and laboratory examination, standard echocardiography completed by Doppler tissue imaging of the tricuspid annular motion, and right-sided heart catheterization. They were followed up for a mean period of 16 months (range, 1-48 months). RESULTS: During the follow-up, there were 28 cardiac-related deaths and 35 non-fatal cardiac events (31 hospitalizations for heart failure decompensation and 4 hospitalizations for malignant arrhythmias requiring the implantation of a cardioverter-defibrillator). The multivariate stepwise Cox regression modeling revealed the right ventricular systolic (represented by the peak systolic tricuspid annular velocity-Sa) and diastolic (represented by the peak early diastolic tricuspid annular velocity-Ea) function to be the independent predictors of event-free survival or survival (p<0.01). The Sa separated better between patients with and without the risk of cardiac events (p<0.05), while the Ea appeared to further distinguish patients with increased risk (those at risk of late event from those at risk of early non-fatal event and early death). The strongest predictive information was obtained by the combination of Sa and Ea creating the Sa/Ea categories. The Sa/Ea I category of patients (Sa>or=10.8 cm s(-1) and Ea>or=8.9 cm s(-1)) had excellent prognosis. On the other hand, the Sa/Ea IV category (Sa<10.8 cm s(-1) and Ea<8.9 cm s(-1)) was found to be at a very high risk of cardiac events (p<0.001 vs. Sa/Ea I). Imbalanced categories of patients (Sa/Ea II and III) with only one component (Sa or Ea) pathologically decreased were at medium risk when assessing event-free survival. However, a significantly better survival (p<0.05) was found in patients with Ea>or=8.9 cm s(-1) (Sa/Ea I and III categories) as compared with those having Ea<8.9 cm s(-1) (Sa/Ea II and IV categories). Thus, in contrast to event-free survival, the survival pattern was determined mainly by the Ea value with only little additional contribution of Sa. CONCLUSIONS: The assessment of right ventricular systolic and diastolic function provides complementary information with a very high power to stratify prognosis of patients with heart failure. The combination of right ventricular systolic and diastolic dysfunction identifies those with a very poor prognosis.

Blood Flow Velocity↗

Long-term survival in patients hospitalized with congestive heart failure: relation to preserved and reduced left ventricular systolic function.

AIMS: The purpose of this study was to evaluate the influence of left ventricular systolic function on the survival in a large consecutive cohort of patients hospitalized with congestive heart failure and to determine how left ventricular systolic function interacts with co-morbid conditions in terms of prognosis. METHODS AND RESULTS: Analysis of survival data from 5491 patients admitted for new or worsening heart failure to 34 departments of cardiology or internal medicine in Denmark from 1993-1996 was carried out. A standardized echocardiogram was available for 95% of the patients, and left ventricular systolic function was estimated using wall motion index score. Follow-up time was 5-8 years. Patients with preserved systolic function were older, more frequently female, and had less evidence of ischemia than patients with systolic dysfunction. After 1 year, 24% of the patients had died. Low wall motion index was a potent independent predictor of death (risk ratio for one unit increase, 0.60 (0.56-0.64)), and was of greater prognostic significance in younger patients and patients with a history of myocardial ischemia. However, even in patients with preserved systolic function, mortality was high (1 year mortality, 19%). CONCLUSION: In hospitalized heart failure patients, particularly in younger patients with ischemic heart disease, mortality risk is inversely related to left ventricular systolic function.

Aged↗

Systolic hypertension and the response to blunt trauma in infants and children.

OBJECTIVES: To describe age-related systolic blood pressures and pulse rates in children following blunt injury. To compare these variables with standard reference values for uninjured children at rest and with reference ranges from the Advanced Paediatric Life Support (APLS) guidelines. DESIGN: Secondary analysis of a prospective cohort. SETTING: Emergency departments throughout England and Wales. PARTICIPANTS: 12906 children presenting with acute blunt traumatic injury from August 1989 to September 1998. MAIN OUTCOME MEASURES: Systolic blood pressure and pulse rate on arrival. RESULTS: Injured children had higher systolic blood pressures than the standard quoted 'norms'. Standard reference values of systolic blood pressure for children at rest always appeared below the 50th percentile for our cohort of injured children (range 7th-27th percentiles). Pulse rates for children at rest were always towards the mid-range for injured children (range 41st-54th percentiles). These results appeared unrelated to injury severity. Age related APLS reference ranges for systolic blood pressure and pulse rate resembled the standard reference values for uninjured children at rest. CONCLUSIONS: Injured children have a relative systolic hypertension compared with children at rest. Pulse rates in the two groups are comparable. Following injury, children with apparently 'normal' age-specific systolic blood pressures on arrival in the Emergency Department are relatively hypotensive and should be carefully assessed.

Adolescent↗

Application of end-systolic pressure-volume and pressure-wall thickness relations in conscious dogs.

The usefulness of end-systolic measures of ventricular function was compared with that of standard contractility indexes in conscious dogs. End-systolic relations between left ventricular pressure and volume and between pressure and wall thickness were analyzed in dogs previously instrumented with ultrasonic crystals. Progressive angiotensin infusions were used to generate computer-averaged pressure-volume and pressure-wall thickness loops. Both relations were linear in every study and highly reproducible. With low and high dose dobutamine, the end-systolic pressure-volume relations were significantly displaced, with increased slope and inconsistent changes in intercept. This relation was more useful than the ejection fraction for detecting contractility increases at different afterloads, but it showed no advantage over maximal left ventricular dP/dt at all ranges of preload and afterload. The end-systolic pressure-volume relations were insensitive for detecting mild decreases in inotropic state produced by propranolol, and maximal dP/dt was superior for detecting such mild acutely reduced contractility. The end-systolic pressure-wall thickness relations showed displacement with dobutamine, although slope and intercept changes were not significant; these relations did not detect mild decreases in contractility produced by propranolol. It is concluded that the end-systolic pressure-volume relation and a simplified end-systolic measure using pressure and wall thickness provide sensitive, load-independent and reproducible approaches for defining acute increases in left ventricular contractility in conscious animals. Maximal dP/dt was equally effective for defining these increases in contractility and more sensitive for detecting slight acute decreases in contractility.

Angiotensin II↗

Angiotensin receptor blockade in the challenging era of systolic hypertension.

Systolic blood pressure is a major cardiovascular risk factor which is often associated with arterial stiffness. Markers of arterial stiffness, such as pulse pressure and carotid-femoral pulse wave velocity, have been proved independent predictors of cardiovascular risk. Recent evidence suggests that the renin-angiotensin system is involved in the pathogenesis of systolic hypertension and arterial stiffness. Outcome trials have shown impressive cardiovascular protection by reducing systolic blood pressure (BP) with drug treatment. However, in clinical practice systolic hypertension remains largely uncontrolled, first, because systolic BP goal is more difficult to be reached than diastolic and, second, because physicians are often reluctant to intensify treatment in patients with systolic BP close to 150 mmHg. Recent trials have focused on the effects of antihypertensive drugs not only on blood pressure, but also on pulse pressure and pulse-wave velocity. Blockade of the renin-angiotensin-aldosterone system, using angiotensin-converting enzyme inhibitors and more recently angiotensin receptor blockers, has been shown to provide beneficial effects on arterial stiffness that appear to be independent of their antihypertensive effects. Recent outcome trials have shown significant cardiovascular protection with angiotensin receptor blockers. These drugs have an excellent placebolike profile of adverse effects which is maintained when these drugs are combined with low-dose diuretics. Therefore, an angiotensin receptor blocker-based treatment strategy appears to be an attractive and evidence-based approach for the management of systolic hypertension, the reduction of arterial stiffness and the prevention of cardiovascular disease.

Angiotensin II Type 1 Receptor Blockers↗

The effect of body heating and cooling on the ankle and toe systolic pressures in arterial disease.

Although changes in body temperature alter limb blood flow, little information exists on the effect of body heating and cooling on systolic pressures in limbs with arterial disease. Ten patients with stable claudication were studied. Mean ankle systolic pressure index during body cooling (0.79 +/- 0.04) exceeded (p less than 0.01) both the value during routine test (0.69 +/- 0.03) and during heating (0.65 +/- 0.04). The individual, paired difference in ankle systolic pressure index between cooling and heating exceeded 0.15 in seven limbs and between cooling and routine test in five. Mean toe systolic pressure index during heating, but not during cooling, was lower than during routine test (p less than 0.01). There was no significant difference in the mean toe systolic pressure index between heating and cooling. However, compared with heating, toe systolic pressure index increased with cooling in 12 limbs and decreased in eight, including three with loss of measurable pressure. The paired difference in toe systolic pressure index between cooling and heating exceeded 0.15 in 10 limbs and between cooling and routine test in eight; whereas between heating and routine test the paired difference was within 0.15 in all but three limbs. The results indicate that changes in body temperature have significant effects on distal pressures in arterial disease. Preliminary warming in routine tests should improve reproducibility.

Aged↗

Isolated systolic hypertension: an important cardiovascular risk factor.

Hypertension is an established risk factor for cardiovascular disease morbidity and mortality. Randomized trials of antihypertensive therapy have demonstrated the benefits of treating diastolic blood pressure, and recently the value of treating isolated systolic blood pressure has also been established. There is an excess risk of cardiovascular disease in subjects with borderline isolated systolic hypertension. In fact, data from men screened for the Multiple Risk Factor Intervention Trial show that the great majority of excess deaths are in those with high-normal systolic blood pressure or with stage 1 hypertension, i.e., systolic blood pressure 130 to 159 mmHg. Similarly, data from the Framingham Heart Study and the Physicians' Health Study emphasize the importance of mild elevations of systolic blood pressure. As age increases the hemodynamic patterns of blood pressure change due to an increase in large artery stiffness, and borderline isolated systolic hypertension becomes the dominant form of hypertension. These facts make the prevention and control of borderline isolated systolic hypertension a key strategic challenge in the effort to prevent excess mortality attributable to blood pressure levels above normal.

Adult↗

Isolated systolic hypertension and mortality after age 60 years. A prospective population-based study.

A total of 165 out of 2636 adults aged 60 years or older (6.3 per cent) in Rancho Bernardo, California, had isolated systolic hypertension with a systolic blood pressure greater than or equal to 160 mmHg and a diastolic blood pressure less than 90 mmHg when studied in 1972-1974. A 6.4-year follow-up of this cohort showed isolated systolic hypertension to be as important a risk factor for all-cause mortality as other types of hypertension in both men and women (adjusted relative risk = 1.5, p greater than 0.10). After adjustment for age and other covariates, male but not female subjects with isolated systolic hypertension experienced an excess risk of death from stroke (relative risk = 4.0, p less than 0.10), a relative risk exceeding that seen in men with treated hypertension. Isolated systolic hypertension was unassociated with an excess risk of fatal ischemic heart disease in subjects of either sex in this population. The excess risk of death and stroke is consistent with results published elsewhere, and supports the concept that isolated systolic hypertension is not a benign condition of the elderly. The efficacy and safety of therapeutic intervention in older adults with isolated systolic hypertension remain to be determined.

Aged↗

Aggregation of blood pressure in the families of children with labile high systolic blood pressure. The Muscatine Study.

The aggregation of systolic blood pressure, diastolic blood pressure, and heart rate is compared among the relatives of three groups of index children: children with low systolic blood pressure (less than the 5th percentile), middle range systolic blood pressure (between the 5th and 95th percentiles), or labile high blood pressure (above the 95th percentile when first sampled but below the 95th percentile when resampled four to six months later). Both systolic and diastolic blood pressures aggregate more strongly in the families of children with labile high systolic blood pressure than in the families of children with middle or low range systolic blood pressure. The degree of aggregation of heart rate does not differ among the three groups. Since blood pressures aggregate so strongly in families of children with labile high systolic blood pressure, study of these children and their families may yield important information about the etiology of hypertension.

Adolescent↗

Left ventricular systolic and diastolic function in aortic stenosis. Prognostic value after valve replacement and underlying mechanisms.

AIMS: The aims of the study were to examine the prognostic value of pre-operative left ventricular systolic and diastolic function on early, and late mortality after valve replacement for aortic stenosis, and to identify possible underlying mechanisms. METHODS AND RESULTS: Ninety-one prospectively recruited consecutive patients with a mean age of 61 years underwent valve replacement for aortic stenosis with concomitant coronary artery bypass grafting in 32 and a minimum postoperative observation period of 5.4 years. There were six early (< or = 30 days postoperatively) and 19 late deaths, and 18 deaths from specific causes (cardiac and prosthetic valve related). Early mortality occurred exclusively among patients with a combined subnormal left ventricular systolic function (subnormal ejection fraction or peak ejection rate, or supranormal time-to-peak ejection--duration of systole ratio) and a subnormal fast filling fraction. In Cox regression models on crude mortality and specific deaths, a subnormal ejection fraction and a fast filling fraction of < or = 45% were the only independent risk factors. Patients with none of these risk factors had normal sex- and age-specific survival, those with any one factor had an early, and those with both factors a massive early and a late excess mortality, with 5-year crude survival of 92%, 77%, and 50%, respectively (P < 0.0001). Systolic wall stress was without prognostic value. Further analyses indicated that impairment of left ventricular function occurred with increasing muscle mass over two phases: (1) diastolic dysfunction characterized by a pattern of severe relative concentric hypertrophy; (2) the addition of systolic dysfunction characterized by a more dilated, less concentric chamber geometry. Coronary artery disease seemed to provoke the latter development sooner. CONCLUSIONS: Impaired systolic and diastolic left ventricular function, irrespective of afterload, were decisive independent pre-operative risk factors for early as well as late mortality after aortic valve replacement for aortic stenosis. The adverse influence of concentric hypertrophy was the main underlying mechanism. Operative intervention, before impairment of diastolic and systolic function, should be advocated.

Adult↗

Causes, implications, and treatment of systolic hypertension.

Mild hypertension is currently defined as systolic blood pressure between 140 and 160 mm Hg. The prevalence of systolic hypertension (including this mild category) in individuals 65 and older is 21% for men and 23% for women. Risk factors include obesity, excessive sodium and alcohol consumption, and possibly calcium and bone metabolism. Determinants of arterial wall rigidity and subsequent increase in pulse-wave velocity are also clearly factors. Much of the associated disease occurs in individuals with systolic pressures between 140 and 159 mm Hg. A particularly high-risk group appears to be those with an elevated systolic blood pressure and a low diastolic blood pressure. Systolic hypertension has now been found to be related to the progression of peripheral atherosclerosis, with lower progression rates among treated individuals. In addition, the beneficial effects of antihypertensive therapy have been found to be strongest among individuals with evidence of subclinical peripheral atherosclerosis. The high prevalence of mild systolic hypertension and its clear association with atherosclerotic disease suggests that older individuals with early systolic hypertension should be identified and treated. Clinical trials to test the efficacy of such treatment should be a high priority, perhaps in subgroups with early subclinical disease.

Arteriosclerosis↗

Massive fetal ascites causing increased middle cerebral artery systolic velocity.

BACKGROUND: An elevated peak systolic velocity in the middle cerebral artery, assessed by Doppler ultrasonography, is commonly associated with fetal anemia. Other fetal abnormalities associated with a high middle cerebral artery velocity have rarely been reported. CASE: A fetus with increasing ascites was found to have an elevated middle cerebral artery peak systolic velocity. Following paracentesis, the peak systolic velocity normalized. Peak systolic velocity continued to correlate with the level of ascites, falling to normal ranges when large-volume amniocentesis and paracentesis were performed. At birth, the infant was found to have a normal hematocrit. CONCLUSION: An elevated middle cerebral artery peak systolic velocity may result from massive fetal ascites without anemia. We hypothesize that the massive ascites led to increased afterload of the heart, with relatively preserved preload, leading to an increased systolic blood pressure and an elevated middle cerebral artery peak systolic velocity.

Adult↗

Determination of central aortic systolic and pulse pressure from the radial artery pressure waveform.

OBJECTIVE: Measurements of central aortic systolic and pulse pressure, either gauged directly or estimated indirectly, have been shown to be superior to brachial pressure in outcome studies. While the radial pressure convolution method has proved to satisfy the criteria for 'substantial equivalence' to measure central pressure non-invasively, this study sought simpler methods to generate central systolic and pulse pressure directly from the radial artery waveform. METHODS: Two sets of data were used, in which radial artery pressure waves were measured by applanation tonometry and ascending aortic pressure was generated by the SphygmoCor process. Different approaches were applied to each dataset: firstly, using the time period from wave foot to systolic peak in central arteries; secondly, through identifying the pressure surge from the reflected wave in the radial artery; and thirdly from extrapolation and calibration of carotid systolic pressure when mean and diastolic pressure considered to be equal with radial values. RESULTS: Both datasets showed good correspondence between the central systolic and pulse pressure obtained with each of the three approaches and respective pressures generated by SphygmoCor process; all were within AAMI SP10 criteria and grade A for BSH criteria. CONCLUSION: All three approaches gave results similar substantially equivalent to those obtained with the SphygmoCor system for aortic, systolic and pulse pressure. Hence, simple inspection of the radial waveform has the potential to improve the estimation of aortic systolic and pulse pressure.

Aorta↗

Systolic arterial pressure recovery after ventricular fibrillation/flutter in humans.

Although the elective induction of cardiac arrest for implantable defibrillator insertion under general anesthesia is widely used, the hemodynamics of recovery of arterial blood pressure after cardiac arrest is not well-defined. Accordingly, the time course of recovery of systolic arterial pressure was studied in seven patients during the repetitive induction of ventricular fibrillation (n = 6) or ventricular flutter (n = 1). The mean number of episodes of cardiac arrest was 7 +/- 2, and the mean drop in systolic pressure was 84 +/- 16 mmHg. The mean recovery time for systolic pressure was 10 +/- 6 seconds, the average systolic pressure recovery rate was 13 +/- 14 mmHg/sec, and the mean percent systolic pressure recovery was 94% +/- 9%. A negative logarithmic relation was found to exist between the rate of systolic arterial pressure recovery and the duration of ventricular fibrillation or flutter with a correlation coefficient of 0.68 to 0.97 (P < 0.05) in five of the seven patients. A linear relation between the time for systolic pressure recovery and duration of asystole was also defined. These results are consistent with the view that prolongation of ventricular fibrillation or flutter increases the duration of arterial pressure recovery through a negative effect on left ventricular contractility. Increased understanding of these relations may lead to increased safety of implantable defibrillator insertion.

Adult↗