首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 0 毫秒
1.
Effects of long-term left ventricular (LV) support on end-stage cardiomyopathy patients is unclear. We applied our LV assist system (LVAS) to six heart transplant candidates, aged 17 to 49, with dilated cardiomyopathy, including one dilated phase hypertrophied cardiomyopathy. LVAS was installed between the left atrium and the ascending aorta, and the pump was positioned parecorporeally. In all patients, their general condition improved, and their pump flows were kept at 4 to 5 L/min. Exercise was started after stabilization of their general condition under constant pump flow. Natural heart size and function were examined by echocardiography. In the beginning of assist, all patients showed impaired cardiac function and LV dilation. During LV assist, systolic function measured by ejection time improved in all patients. Left ventricular end-diastolic dimension (LVDd), showed a remarkable decrease in two patients, who were weaned from LVAS after 3 months of support. They are doing well more than 1 year and 3 years after removal; peak VO2 levels (ml/min/kg) were 30 at 1.2 years and 27 at 2.7 years after removal. In the other four patients, however, LVDd had no remarkable changes, and three could not be weaned from LVAS. The last was discontinued from LVAS after 5 months of support because of infection and died 2 months after removal. From this experience, long-term LVAS may provide the chance for recovery of the natural heart in patients with end-stage cardiomyopathy. The patients whose hearts showed remodeling were able to be weaned from LVAS, and their heart function maintained in good condition for several years.  相似文献   

2.
BACKGROUND: In hypertrophic cardiomyopathy, ejection fraction is normal or increased, and force-length relations are reduced. However, three-dimensional (3D) motion and deformation in vivo have not been assessed in this condition. We have reconstructed the 3D motion of the left ventricle (LV) during systole in 7 patients with hypertrophic cardiomyopathy (HCM) and 12 normal volunteers by use of magnetic resonance tagging. METHODS AND RESULTS: Transmural tagging stripes were automatically tracked to subpixel resolution with an active contour model. A 3D finite-element model was used to interpolate displacement information between short- and long-axis slices and register data on a regional basis. Displacement and strain data were averaged into septal, posterior, lateral, and anterior regions at basal, midventricular, and apical levels. Radial motion (toward the central long axis) decreased slightly in patients with HCM, whereas longitudinal displacement (parallel to the long axis) of the base toward the apex was markedly reduced: 7.5 +/- 2.5mm (SD) versus 12.5 +/- 2.0 mm, P < .001. Circumferential and longitudinal shortening were both reduced in the septum (P < .01 at all levels). The principal strain associated with 3D maximal contraction was slightly depressed in many regions, significantly in the basal septum (-0.18 +/- 0.05 versus -0.22 +/- 0.02, P < .05) and anterior (-0.20 +/- 0.05 versus -0.23 +/- 0.02, P < .05) walls. In contrast, LV torsion (twist of the apex about the long axis relative to the base) was greater in HCM patients (19.9 +/- 2.4 degrees versus 14.6 +/- 2.7 degrees, P < .01). CONCLUSIONS: HCM patients had reduced 3D myocardial shortening on a regional basis; however, LV torsion was increased.  相似文献   

3.
We report the case of an 85-year-old woman with distal LV hypertrophy resulting in an intraventricular pressure gradient and incomplete systolic emptying who benefited from permanent DDD pacing. Our experience based on this case suggests that permanent dual chamber pacing might be a safe and effective therapy also in symptomatic patients with the rare form of hypertrophic cardiomyopathy with left mid-ventricular obstruction resulting in incomplete emptying of the apical portion of the LV and a significant intraventricular pressure gradient that was not responding to pharmacological therapy.  相似文献   

4.
Left ventricular wall motion was assessed in 105 consecutive patients both invasively, using biplane cineangiography, and noninvasively, by a real-time, phased-array, two-dimensional echocardiography system. Ventricular wall motion in five anatomic areas of the ventricle (anterolateral, posterolateral, apical, septal, and inferior) was analyzed by both methods in a double-blind manner. Two-dimensional echocardiographic images were deemed adequate for analysis in 82% of the regions (430 of 525). Fifty-five discrepancies were noted in the comparison of the remaining 430 regions. The reasons for discrepancies in interpretation between the two methods were established for 54 during retrospective review: 33 were due to echocardiography (inadequate target visualization, observer error, or tangential echo views). Fifteen were related to angiography (overlay of silhouettes or observer error), and six were due to other reasons including definition problems or spatial orientation difficulties. Both real-time, two-dimensional echocardiography and cineangiography have advantages and disadvantages. The techniques used together could provide more complete information concerning ventricular wall movement than is now currently available.  相似文献   

5.
Whether volume expansion influences NaC1 reabsorption by the diluting segment of the nephron remains a matter of controversy. In the present studies this question has been examined in normal unanesthetized dogs, undergoing maximal water diuresis. Free water clearance (CH2O/GFR) has been used as the index of NaC1 reabsorption in the diluting segment. Three expressions have been employed for "distal delivery" of NaC1: a) V/GFR, designated as the "volume term"; b) (CNa/GFR + CH2O/GFR), the "sodium term;" and c) (CC1/GFR + CH2O/GFR), the "chloride term". The validity of these terms is discussed. Three techniques were used to increase distal delivery: 1) the administration of acetazolamide to dogs in which extracellular fluid (ECF) volume was not expanded (grop 1); 2) "moderate" volume expansion (group 2); and 3) "marked" volume expansion (group 3). CH2O/GFR increased progressively with rising values for "distal delivery" regardless of which term was used to calculate the latter. With all three delivery terms, differences in distal NaC1 reabsorption emerged between the two volume-expanded groups, though only with the "chloride" term did substantial differences also emerge between the nonexpanded group 1 dogs and both volume-expanded groups. In group 1, values for CH2O/GFR increased in close to a linear fashion up to distal delivery values equal to 24% of the volume of glomerular filtrate. However, at high rates of distal delivery the rate of rise of CH2O/GFR was less in group 2 than in group 1 and the depression of values was even greater in group 3. Within the limits of the techniques used, the data suggest that volume expansion inhibits fractional NaC1 reabsorption in the diluting segment of the nephron in a dose-related fashion. The "chloride" term was found to be superior to the "volume" and "sodium" terms in revealing these changes.  相似文献   

6.
BACKGROUND: Prolonged antihypertensive therapy might be less effective in reversing the left ventricular hypertrophy (LVH) in uremics bearing the deleted (DD) allele of the angiotensin converting enzyme (ACE) gene than in patients with the inserted (II) allele or in those heterozygous (ID) for the gene. METHODS: Thirteen DD and 17 II + ID hemodialyzed uremics were followed-up with yearly echocardiography and 24-hour blood pressure (BP) monitoring over five years while on an antihypertensive therapy that included ACE inhibitors as first line drugs. RESULTS: In the II + ID group there were significant decreases of the left ventricular mass index (LVMi) and of both systolic and diastolic BPs. These changes were less pronounced in the DD group, but the difference was not statistically significant given the wide overlap between the two groups. Further analysis of the data revealed that the only factor associated to a decreased LVMi was the decrease of the systolic BP irrespective of the ACE gene genotype of each individual patient. CONCLUSIONS: The ACE-gene genotype does not necessarily predict the extent to which LVMi will be lowered by ACE-inhibitors therapy. The LVH of hypertensive uremics is amenable by long-term antihypertensive therapy provided that it results in significantly decreased systolic blood pressure.  相似文献   

7.
BACKGROUND: Myocardial revascularization in patients with left ventricular failure (ejection fraction < 30%) offers survival comparable to heart transplantation. The functional outcome, however, has yet to be determined. In order to assess the clinical results in patients with LVEF < 30% undergoing coronary artery bypass grafts (CABG), 101 consecutive patients operated between 1/91 and 1/97 were reviewed retrospectively. METHODS: The patients were stratified according to presentation: 65 pts had angina (Group 1) and 36 congestive failure (Group 2). Mean age (62 +/- 7 vs 60 +/- 8 yrs), sex (90 vs 88% male), LVEF (0.28 +/- 0.04 vs 0.29 +/- 0.04), prior myocardial infarction (1.2 +/- 0.4 vs 1.2 +/- 0.5 episodes/pt), presence of vital myocardium at scintiscan or low-dose dobutamine echocardiography (92 vs 93%), need for preoperative IABP (3.1 vs 8.3%), aortic cross-clamp (53 +/- 21 vs 60 +/- 21 min) and cardiopulmonary bypass (104 +/- 31 vs 114 +/- 36 min) times were comparable. RESULTS: There was only 1 (1%) perioperative death due to low-output syndrome. Eleven pts (6 vs 5, Group 1 vs Group 2) had postoperative low-output syndrome, requiring IABP in 7 pts (4 vs 3). There were 14 (10 vs 4, Group 1 vs Group 2) deaths during follow-up (29 +/- 19 months, range 2-67), with an overall actuarial survival of 91 +/- 4 vs 100% at 1 yr and 74 +/- 9 vs 78 +/- 10% at 5 yrs in Group 1 vs Group 2, respectively (p = ns). Actuarial symptom-free survival was 89 +/- 4 vs 84 +/- 6% at 1 yr and 49 +/- 9 vs 28 +/- 11% at 5 yrs, respectively (p = 0.05). Despite the high recurrence of congestive failure (22 vs 66% in Group 1 vs Group 2, p = 0.004), improvement in functional class (3.1 +/- 0.8 vs 1.5 +/- 0.7 in Group 1 and 2.7 +/- 0.7 vs 1.8 +/- 0.5 in Group 2) and LVEF (0.28 +/- 0.04 vs 0.38 +/- 0.04 in Group 1 and 0.29 +/- 0.04 vs 0.40 +/- 0.06 in Group 2) was found in both groups at follow-up. CONCLUSIONS: In spite of improving early and late survival after revascularization for ischemic left ventricular failure, patients presenting with congestive failure have an unsatisfactory symptom-free survival. Further studies are necessary to ascertain the relative indications to revascularization or transplantation in this specific patient subgroup.  相似文献   

8.
OBJECTIVES: This study sought to assess the effects of partial left ventriculectomy (PLV) on left ventricular (LV) performance in a series of consecutive patients with nonischemic dilated cardiomyopathy. BACKGROUND: Reduction of LV systolic function in patients with heart failure is associated with an increase of LV volume and alteration of its shape. Recently, PLV, a novel surgical procedure, was proposed as a treatment option to alter this process in patients with dilated cardiomyopathy. METHODS: We studied 19 patients with severely symptomatic nonischemic dilated cardiomyopathy, before and 13+/-3 days after surgery, and 12 controls. Single-plane left ventriculography with simultaneous measurements of femoral artery pressure was performed during right heart pacing. RESULTS: The LV end-diastolic and end-systolic volume indexes decreased after PLV (from 169 to 102 ml/m2, and from 127 to 60 ml/m2, respectively, p < 0.0001 for both). Despite a decrease in LV mass index (from 162 to 137 g/m2, p < 0.0001), there was a significant decrease in LV circumferential end-systolic and end-diastolic stresses (from 277 to 159 g/cm2, p < 0.0001 and from 79 to 39 g/cm2, p = 0.0014, respectively). Ejection fraction improved (from 24% to 41%, p < 0.0001); the stroke work index remained unchanged. CONCLUSIONS: The PLV improves LV performance by a dramatic reduction of ventricular end-systolic and end-diastolic stresses. Further studies are needed to assess whether this effect is sustained during long-term follow-up and to define the role of PLV in the treatment of patients with dilated cardiomyopathy.  相似文献   

9.
Electrocardiographic left ventricular hypertrophy (LVH) and related repolarization changes alter the morphology of the ST segment and/or the T wave. Such electrocardiographic abnormalities--all features that are encountered in patients with acute ischemic heart disease--may confound the early emergency department evaluation of the chest pain patient. In the instance of the chest pain patient demonstrating ST segment/T wave abnormality, the correct electrocardiographic diagnosis must be made not only to offer appropriate management for that particular illness but also to avoid the incorrect application of potentially dangerous therapies such as thrombolysis. This report presents two cases in which the electrocardiogram demonstrated significant repolarization changes consistent with LVH, and focuses on the recognition of the expected ST segment/T waves changes and their differentiation from the primary ST segment/T wave changes associated with acute ischemic heart disease.  相似文献   

10.
We report a case of incessant ventricular tachycardia with right bundle branch block and left axis deviation morphology resulting in severe LV dysfunction and congestive heart failure. Radiofrequency ablation of the appropriate site in the region of posteroapical part of the LV septum resulted in the cure of the arrhythmia. On a 3-month follow-up, the LV size and function returned to normal.  相似文献   

11.
12.
This paper reports the first case of hypertrophic cardiomyopathy (HCM) that developed postpartum congestive heart failure (CHF) and severe left ventricular (LV) systolic dysfunction. Review of the literature and clinical implications are discussed.  相似文献   

13.
To determine the prognostic importance of pulsed Doppler-derived left ventricular diastolic filling velocity profiles and the relationship between Doppler variables and clinical functional status, the follow-up outcome of 58 patients with dilated cardiomyopathy and symptoms of left ventricular dysfunction was analysed. During a mean follow-up period of 31.2 +/- 12.8 months, 23 died of either progressive pump failure or sudden death. Peak early filling velocity (E) was higher and late atrial filling velocity (A) lower in nonsurvivors than in survivors. The E/A ratio was higher and the deceleration time (DT) of early diastole shorter in nonsurvivors. The mortality was significantly higher in patients with an E/A ratio > 2 or a DT < 150 ms than in those without. Repeated Doppler echocardiographic examinations in 31 of 35 survivors after intense treatment showed decreased E, increased A, reduced E/A ratio and prolonged DT in 18 patients with clinical functional improvement, whereas these measurements were unaltered in the remaining 13 patients whose functional status was unchanged or deteriorated. This study suggests that pulsed Doppler-derived left ventricular diastolic filling variables may be important predictors of outcome in dilated cardiomyopathy and provide useful measures in observing the effects of therapy during long-term follow-up of the patients.  相似文献   

14.
BACKGROUND: The study was designed to evaluate short and long-term benefits of coronary artery bypass graft in patients with coronary artery disease and severely depressed left ventricular ejection fraction and to identify contemporary risk factors associated with significantly greater mortality in this high-risk subgroup. METHODS: From 1985 to 1995, 200 consecutive pts with EF < or = 0.30 underwent CABG. Among these patients, 60% were older than 70 years. NYHA functional class III/IV was present in 31% of pts. Preoperative mean cardiac index was 2.7 +/- 7 l/min/m2, mean pulmonary artery pressure was 29.9 +/- 7 mm Hg and contractility score (generated by appropriate software for left ventricular kinesis analysis) mean value was 50.1 +/- 11.6 points. Urgent operation was required in 32 pts (16%). The majority of pts were completely revascularized. RESULTS: Operative mortality was 9% (18 pts). Low output syndrome was the most common postoperative complication (13.5%) followed by ventricular arrhythmia (8%), mean length of postoperative hospitalization for survivors was 13 +/- 10 days. Of 23 possible operative risk factors evaluated, four were associated with significantly greater mortality: cardiac index < or = 2.1 l/min/m2, urgent operation, contractility score > or = 80 and associated surgical procedures. Survivors experienced significant improvement in CHF class (p < 0.001) and follow up EF (p < 0.001). Kaplan-Meier estimate of survival at 1 year, 5 years and 8 years was 85%, 65% and 54%. CONCLUSION: Through more careful assessment of preoperative risk factors, patients selection and perioperative management, actually coronary artery bypass graft may be offered to pts with low ejection fraction with reduced morbidity and mortality.  相似文献   

15.
16.
Ischemic heart disease, once limited to a number of well defined entities such as angina of effort, unstable angina, and myocardial infarction, must now be regarded as a much more complex and elusive entity. Silent ischemia was the first of the new ischemic syndromes to be described. Recently, three further new syndromes have been added, namely stunning, hibernation and preconditioning. All three have one common theme--they can be related to ischemia and reperfusion. In stunning, there is post-reperfusion mechanical dysfunction that recovers. In hibernation, there is prominent contractile dysfunction, apparently out of proportion to the reduction in coronary flow, and the recovery upon reperfusion is good. In preconditioning, severe ischemia followed by reperfusion protects against subsequent ischemia which may modify the severity of ischemic damage in the other ischemic syndromes. Ischemic LV dysfunction as found in post-infarct patients and in the absence of any simple relation to reperfusion, can be either diastolic or systolic or both in nature. In ischemic LV diastolic dysfunction without major systolic dysfunction, calcium antagonists may be appropriate therapy which could point to a role for abnormalities in the regulation of cytosolic calcium. It is proposed that there is potentially a mixed post-infarct syndrome, which may comprise one or more of the new ischemic syndromes (silent ischemia, stunning, hibernation, and preconditioning), as well as a varying degree of systolic and/or diastolic dysfunction. The basis of the systolic dysfunction is, at least in part, post-infarct LV remodeling. Several of these entities could overlap in the same patient. The term "mixed post-infarct ischemic syndrome" is suggested to describe this condition.  相似文献   

17.
18.
The effects of coronary artery disease on patterns of left ventricular contractility have been thoroughly investigated. In contrast, little is known about the incidence of right ventricular dysfunction induced by this disease. To evaluate the frequency of right ventricular asynergy, biplane right ventricular cineangiograms were obtained in 26 patients. Seven segmental axes of shortening were analyzed in each end-systolic and end-diastolic frame and normalized as percent decrease (or increase) in axis from end-diastolic length. Of 26 patients, 8 (Group I) served as normal (control) subjects. The remaining 18 patients had significant coronary artery disease; 6 of these (Group II) had no significant disease of the right coronary artery, whereas 12 (Group III) had significant obstruction of this artery. Four patients in Group II had a previous anteroseptal myocardial infarction, and six in Group III had a previous inferior myocardial infarction. There was a progressive decrease in segmental axes of shortening from Group I to II and from Group II to II, but the decrease was not significant at the level P less than 0.01. Only one patient in Group II had frank dyskinetic segmental motion of the interventricular septum (this patient had had a previous anteroseptal myocardial infarction), whereas two patients in Group III had dyskinetic segmental motion of the free right ventricular wall (both had previous inferior myocardial infarction). Therefore, coronary artery disease seldom produces significant right ventricular asynergy. Abnormal septal motion is associated with previous anteroseptal myocardial infarction; however, dyskinetic motion of the free right ventricular wall occurs only in patients with a right coronary arterial lesion and previous inferior myocardial infarction.  相似文献   

19.
BACKGROUND: Engagement in therapeutic activity among stroke inpatients is advocated by many rehabilitation professionals. However, there is a lack of published evidence to indicate whether this is currently being achieved. OBJECTIVE: To investigate the extent and types of 'rehabilitation' activities on a new neurological rehabilitation ward, and examine change in patients' behaviour related to the new environment and new initiatives. DESIGN: Five one-week observation periods were conducted over two years, with a total of 67 patients being observed. A comparison was made with results of an earlier study of stroke patients' activities conducted at the same hospital. RESULTS: Patients spent an average 43 min per day with therapists (9% of the working day) and this was only marginally supplemented by self-exercise (2% of the working day--approximately 10 min). However, the provision of a new rehabilitation environment was associated with a marked decrease in the time patients spent at their bedsides, and a decrease in time spent passively gazing or watching others. CONCLUSIONS: Overall there was some positive change in patients' behaviour. We suggest that structured guidance is required from the whole multidisciplinary team to stimulate more self-directed therapy practice and recreation.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号