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 34 毫秒
1.
A case of bilateral coarctation of the frontal horns with acute distension of the trigones is presented, and treatment with a bilateral ventriculoatrial shunt is discussed. Literature on the subject is considered, and a hypothesis is made concerning the pathogenesis of this very rare disorder.  相似文献   

2.
The Gyro centrifugal pump, PI (permanently implantable) series, is being developed as a totally implantable artificial heart. Our final goal is to establish a "functional TAH," a totally implantable biventricular assist system (BiVAS) with centrifugal pumps. A plastic prototype pump, Gyro PI 601, was evaluated through in vitro and in vivo studies as a single ventricular assist device (VAD). Based upon these results, the pump head material was converted to a titanium alloy, and the actuator was modified. These titanium Gyro pumps, PI 700 series, also were subjected to in vitro and in vivo studies. The Gyro PI 601 and PI 700 series have the same inner dimensions and characteristics, such as the eccentric inlet port, double pivot bearing system, secondary vane, and magnet coupling system; however, the material of the PI 700 is different from the PI 601. The Gyro PI series is driven by the Vienna DC brushless motor actuator. The inlet cannula of the right ventricular assist system (RVAS) specially made for this system consists of 2 parts: a hat-shaped silicone tip biolized with gelatin and an angled wire reinforced tube made of polyvinylchloride. The pump-actuator package was implanted into 8 calves in the preperitoneal space, bypassing from the left ventricle apex to the descending aorta for the left ventricular assist system (LVAS) and bypassing the right ventricle to the main pulmonary artery for the RVAS. According to the PI 601 feasibility protocol, 2 LVAS cases were terminated after 2 weeks, and 1 LVAS case and 1 RVAS were terminated after 1 month. The PI 700 series was implanted into 4 cases: 3 LVAS cases survived for a long term, 2 of them over 200 days (72-283 days), and 1 RVAS case survived for 1 month and was terminated according to the protocol for a short-term antithrombogenic screening and system feasibility study. Regarding power consumption, the plastic pump cases demonstrated from 6.2 to 12.1 W as LVAS and 7.3 W as RVAS, the titanium pump cases showed from 10.4 to 14.2 W as LVAS and 15.8 W as RVAS. All cases exhibited low hemolysis. The renal function and the liver function were maintained normally in all cases throughout these experimental periods. In the 2 RVAS cases, pulmonary function was normally maintained. No calves demonstrated thromboembolic signs or symptoms throughout the experiments except Case 1 with the plastic pump. However, in the plastic pump cases, bilateral renal infarction was suspected in 2 cases during necropsy whereas no abnormal findings were revealed in the titanium pump cases. There were also no blood clots inside the PI 700 series. As for the 601, the explanted pumps demonstrated slight thrombus formations at the top and bottom pivots except in 1 case. The Gyro PI series, especially the PI 700 series, demonstrated superior performance, biocompatibility, antithrombogenicity and low hemolysis. Also, the durability of the actuator was demonstrated. Based on these results, this titanium centrifugal pump is suitable as an implantable LVAS and RVAS. It is likely that the Gyro PI series is a feasible component of the BiVAS functional TAH.  相似文献   

3.
Severe, medically unresponsive pulmonary hypertension (PHT) is considered to be a contraindication for orthotopic heart transplantation (OHT). Chronic left ventricular (LV) unloading using a left ventricular assist device (LVAD) might result in reversal of the elevated pulmonary vascular resistance (PVR), allowing successful OHT in such patients. In this study, we present a patient with end-stage ischemic cardiomyopathy and fixed, elevated PVR (7.1 Wood units) who underwent implantation of a Novacor LVAD (Baxter Healthcare Corp., Deerfield, IL, U.S.A.), with a subsequent reduction in PVR to 1.2 Wood units and successful OHT eleven months post-LVAD implantation. Three years after heart transplant, the patient still leads an active life with no right heart failure. In conclusion, OHT is not contraindicated in patients with end-stage heart failure and medically unresponsive PHT in the presence of elevated left atrial pressure. Left ventricular unloading should be considered in these patients to allow reversal of the elevated PVR before OHT.  相似文献   

4.
Abstract: Right ventricular (RV) failure during the use of a left ventricular assist device (LVAD) is the leading cause of death in circulatory support patients. Previous work, both experimentally and clinically, has shown the difficulties in predicting the behavior of the right ventricle at the start of LVAD. An experimental study has been designed to evaluate RV functional changes during LVAD and its relation to preload changes. The model used adult mongrel pigs (n = 10). Right ventricular functional parameters were measured with a thermodilution RV ejection fraction catheter. The left ventricle was supported by a Nippon Zeon blood pump. Two groups were studied, the first one was the LVAD–off group (n = 5) and the other was the LVAD–on group (n = 5) which was supported by LVAD at maximum flow. Change of cardiac output, mean pulmonary artery pressure (PAP), RV stroke work, and RV ejection fraction in both groups were not significantly different. However, the relationship between right ventricular end–diastolic pressure (RV–EDP) and right ventricular stroke volume (RVSV) was significantly changed at a high level of RV–EDP. When RV–EDP was over 6. 5 mm Hg in the LVAD–off group, RVSV decreased to 52. 3 ± 11. 5 ml while in the LVAD–on group, RVSV increased to 97. 2 ± 22. 0 ml. The change in PAP in the LVAD–on group was lower than in the LVAD–off group. We conclude that, at the volume overload state, LVAD can reduce the afterload of the right ventricle and maintain Frank–Starling's effect, thus having a beneficial effect on right ventricular performance.  相似文献   

5.
右心室肥厚(right ventricular hypertrophy, RVH)和右心室衰竭(right ventricular failure, RVF)是具有致命性的恶性心脏疾病,肺动脉高压(pulmonary arterial hypertension, PAH)是主要的致病因素。大量研究已经发现,Ca ...  相似文献   

6.
An implantable biventricular assist device (BVAD) has been developed at Baylor College of Medicine using 2 centrifugal blood pumps. The aim of this study was to investigate the exercise-reflex response during nonpulsatile biventricular assistance and to evaluate to which degree the autoregulation of the system would accommodate the changed hemodynamic situation during physical exercise. The Baylor Gyro PI 710 BVAD has been implanted into 2 calves (strain half-Dexter) in a biventricular bypass fashion with native heart remaining. Allowing a 10 day convalescence, 2 animals were subjected to incremental exercise tests. The speed of the treadmill was increased at zero slope from 0.7 mph to 1.5 mph with increments of 0.2 mph every 3 min. During the exercise the pump flows were maintained at a fixed rate (6.93 +/- 0.01 L/min for the left ventricular assist device and 5.36 +/- 1.44 L/min for the right ventricular assist device). Hemodynamic parameters and pump performance were recorded continuously. The cardiac output (CO) and heart rate (HR) increased significantly during the exercise. CO increased from 11.1 +/- 0.3 to 13.1 +/- 0.4 L/min, and HR increased from 99 +/- 7.1 to 114 +/- 2.8 bpm, respectively. Mean aortic pressure, central venous pressure, and left arterial pressure did not change significantly. Also, no change was observed for the left and right pump flows. This totally implantable BVAD showed excellent long-term performance without any mechanical problems. It is feasible to operate without impairment under physical activity. However, the natural heart dominated the hemodynamic response during exercise under BVAD support. The left and the right pump flows did not increase spontaneously with exercise. We therefore conclude that a servo CO control system is necessary to regulate pump flows even during moderate exercise.  相似文献   

7.
One emergency ambulance serving an urban part of the greater Stockholm area was equipped with a semi-automatic defibrillator Life Pack 200 Physio Control during an 8-month study period. The equipment advises the user whether defibrillation is required or not, and in cases of detected ventricular fibrillation, defibrillation is advised. The user then has to press a button to defibrillate through the same electrodes that record the electrocardiogram. A built-in tape recorder was used for documentation of the underlying rhythm disturbance. In all, advice was requested 332 times. Accuracy in interpretation of ventricular fibrillation was found to be high. The sensitivity and specificity in interpretation of ventricular fibrillation were 93% and 100%, respectively. No defibrillations were performed in patients without ventricular fibrillation. All instances of ventricular fibrillation were converted to another rhythm or asystole. Seven percent of the patients with cardiac arrest caused by ventricular fibrillation survived.  相似文献   

8.
9.
BACKGROUND: It is well known that both pressure and volume overloads contribute to left ventricular hypertrophy (LVH) and left ventricular dilatation in patients with chronic kidney disease (CKD). Few studies have evaluated the association between increased pulse wave velocity (PWV) and LVH in CKD patients not yet receiving dialysis. The purpose of this study was to assess the relationship between arterial stiffness and cardiac remodelling in patients with CKD, and to determine the independent factors associated with increased left ventricular mass index (LVMI) and left ventricular volume index (LVVI). METHODS: This cross-sectional study included 96 patients with CKD. Echocardiography and measurement of arterial stiffness by PWV were performed. Clinical and echocardiographic parameters were compared and analysed. RESULTS: Associated with the increase of PWV, there were significant trends for progressive increase in LVMI, LVH, LVVI, left ventricular dilatation and left atrium in CKD patients. Multivariate regression analysis revealed that decreased PWV, in addition to increased haemoglobin and the use of beta-blocker, was an independent determinant associated with decrease in LVMI and LVVI. CONCLUSION: Our study demonstrated the progressive structural remodelling of left ventricle and left atrium in CKD patients associated with increased severity of arterial stiffness. PWV was an important determinant of LVMI and LVVI in CKD patients.  相似文献   

10.
11.
There are many causes of ventricular arrhythmias in pediatric patients, even those with structurally normal hearts. However, in young patients with 'normal' hearts, sustained ventricular arrhythmias are relatively rare. The primary concern of the physician is to identify which patients have benign ventricular arrhythmia patterns and which are at risk for sudden cardiac death. Even in asymptomatic patients, the choice of anesthetic agents may be important to minimize precipitation of episodes of tachyarrhythmias. This clinical report describes the anesthetic considerations for an asymptomatic child with a history of sustained premature ventricular contractions, ventricular tachycardia, and bigeminy. This child had chronic serous otitis media requiring repeat tympanostomy and tube replacement. This case report outlines the initial cancellation of anesthesia because of sustained arrhythmias, and subsequent conduct of the anesthesia for the case, as well as the considerations in the selection of the drugs when a child presents with significant ventricular arrhythmia.  相似文献   

12.
We report an 83-year-old man with a mycotic left ventricular apical pseudoaneurysm and aortic prosthetic valve endocarditis caused by Enterococcus spp. Mycotic left ventricular pseudoaneurysm is very rare and is associated with a high risk of rupture. Here, we report the clinical presentation, diagnosis, prognosis, and treatment of a case of mycotic left ventricular pseudoaneurysm to raise awareness regarding this unusual and potentially fatal complication.  相似文献   

13.
目的 分析冠心病合并左室室壁瘤形成患者仅行冠状动脉旁路移植术(CABG)但未同期行左心室成形术的疗效。 方法 2008年1月至2012年12月武汉亚洲心脏病医院收治冠心病合并室壁瘤患者共105例,术中探查发现室壁瘤边界欠清或活动欠佳或无明显矛盾运动而未处理室壁瘤患者共74例,其中男59例,女15例;年龄 (60.96±9.09) 岁。冠状动脉造影显示:单支血管病变5例,双支病变10例,3支病变45例,左主干+3支病变14例。术中发现30例室壁瘤界限不清,29例心尖室壁变薄、室壁瘤不明显,15例室壁瘤未见明显的矛盾运动、心尖部质地较厚。所有患者均行冠状动脉旁路移植术。在体外循环下手术62例,非体外循环下手术12例。70例采用左乳内动脉吻合于左前降支,2例行左前降支内膜剥脱术。因二尖瓣中-重度反流行二尖瓣成形术3例,二尖瓣置换术2例;因合并主动脉瓣重度狭窄同期行主动脉瓣置换术1例。 结果 术后因恶性心律失常、缺血、缺氧性脑病死亡2例 (2.7%);因低心排血量、围术期心肌梗死、恶性心律失常等行主动脉内球囊反搏 (IABP) 辅助6例。术后随访70例,随访时间24~60 (43±12) 个月。随访期间发现心室内血栓形成8例,其中5例服用华法林1年内血栓消失,无1例发生血栓脱落栓塞事件。超声心动图检查提示:室壁瘤消失18例 (25.7%)。出院时、术后6个月、1年射血分数较术前明显增高 (术后6个月与术前比较:44%±6% vs. 39%±5%),左心室舒张期末内径 [术后6个月与术前比较:(54.37±6.28) mm vs. (59.24±6.24)mm]、左心室收缩期末内径与术前比较明显缩小 (P<0.01)。但随着时间延长,左心室舒张期末内径、左心室收缩期末内径较出院时逐渐增大。 结论 对于合并室壁瘤的冠心病患者,根据术中探查实际情况未行左心室成形术仅行冠状动脉旁路移植术,术后射血分数、左心室舒张期末内径、左心室收缩期末内径均较术前明显改善,但术后心室扩大呈进行性发展。  相似文献   

14.
Open in a separate window OBJECTIVESLeft ventricular assist device (LVAD) implantation for end-stage heart failure patients has been on the rise, providing a reliable long-term option. For some LVAD patients, longer term LV unloading leads to recovery; hence, the need for evaluating potential myocardial recovery and weaning eligibility has emerged.METHODSAll patients who underwent contemporary LVAD explantation at our institution between 2009 and 2020 were included in the study. Patients in New York Heart Association I, left ventricular ejection fraction >40%, a cardiac index >2.4 l/min and a peak oxygen intake >50% predicted underwent a 4-phase weaning assessment. A minimally invasive approach using a titanium plug was the surgery of choice in the most recent explants. Kaplan–Meier curves were used to estimate the survival at 1 and 5 years.RESULTSTwenty-six patients (17 HeartMate II, 9 HeartWare) underwent LVAD explantation after a median 317 days of support [IQ (212–518)], range 131–1437. Mean age at explant was 35.8 ± 12.7 years and 85% were males. Idiopathic dilated cardiomyopathy was the underlying diagnosis in 70% of cases. Thirteen (48%) patients were on short-term mechanical circulatory support and 60% required intensive care unit admission prior to the LVAD implantation. At 1 year, Kaplan–Meier estimated survival was 88%, whereas at 6 years, it was 77%. The average left ventricular ejection fraction at 1 year post-explant was 44.25% ± 8.44.CONCLUSIONSThe use of a standardized weaning protocol (echocardiographic and invasive) and a minimally invasive LVAD explant technique minimizes periprocedural complications and leads to good long-term device-free survival rates.  相似文献   

15.
Objective To retrospectively review the experience of anesthesia for aortic valve insufficiency complicated with extremely dilated left ventricle.Methods The patients were premedieated with morphine 10 mg and scopolamine 0.3 mg IM.Anesthesia was induced with etomidate 0.1-0.2 ms/ks.sufentanil 1μ/kg and pipecuronium 0.1 mg/kg.After the patients were intubated,anesthesia wag maintained beween 1.0%and 1.5% isoflurane and intermittent Ⅳ boluses of sufentanil and pipecuronium.ECG,direct BP,SpO2,PET CO2,CVP and body temperature were monitored during anesthesia.Result All patients Were rehabilitated without ventricular fibrillation and arrhythmia.Conlusions Measures are taken before the surgery to maintain preload,increase heart rate,reduce afterload moderately and maintain myocardial contractility.After the surgery,maintenance of preload is helpful for ensuring adequate forward flow and benefcial to patients using dopamine and nitrolycerin.  相似文献   

16.
Objective To retrospectively review the experience of anesthesia for aortic valve insufficiency complicated with extremely dilated left ventricle.Methods The patients were premedieated with morphine 10 mg and scopolamine 0.3 mg IM.Anesthesia was induced with etomidate 0.1-0.2 ms/ks.sufentanil 1μ/kg and pipecuronium 0.1 mg/kg.After the patients were intubated,anesthesia wag maintained beween 1.0%and 1.5% isoflurane and intermittent Ⅳ boluses of sufentanil and pipecuronium.ECG,direct BP,SpO2,PET CO2,CVP and body temperature were monitored during anesthesia.Result All patients Were rehabilitated without ventricular fibrillation and arrhythmia.Conlusions Measures are taken before the surgery to maintain preload,increase heart rate,reduce afterload moderately and maintain myocardial contractility.After the surgery,maintenance of preload is helpful for ensuring adequate forward flow and benefcial to patients using dopamine and nitrolycerin.  相似文献   

17.
18.
Intra-aortic balloon pumping to support the failing circulation is now an accepted therapeutic modality. The device is simple. Insertion can be accomplished rapidly and efficiently in emergency rooms, coronary care units, cardiac catheterization suites and operating rooms, preoperatively, intraoperatively and postoperatively. The hemodynamic effects are immediate and predictable, and the accruing clinical results show increasing survival and hospital discharge rates. In these institutions, mechanical support of the circulation by this and more advanced methods has been formalized within the responsibility of a Circulatory Support Service.
The purpose of this Report is to summarize some observations and analyses which have been made during care of 325 consecutive postcardiotomy and/or postinfarction cardiogenic shock patients. Historical, theoretical, basic, and applied aspects and current results are included. Foremost are the straightforward concepts of considering the heart as a pump, the failing heart as a failing pump and intra-aortic balloon pumping as a temporary intravascular, auxiliary pump, capable of stabilizing or reversing that failure if utilized early in its evolution.  相似文献   

19.
A 61-year-old woman with profound hypothyroidism under-went surgery for a ventricular septal perforation 15 days following an acute myocardial infarction, with no preoperative thyroid replacement. Her immediate postoperative course was complicated by a low cardiac output, respiratory suppression and high output renal failure, requiring prolonged hemodynamic and respiratory support. Thyroid replacement (50 μg of thyronine and 100 μg of thyroxine daily) was given in two installments on the 2nd day after the operation. The effect of the inotropic agents increased gradually and the patient was weaned off intra-aortic balloon pumping. A large quantity of diuretics, hydration and hyperalimentation also successfully reduced her elevated BUN and serum creatinine. After full thyroid replacement, she was discharged in good health on the 40th postoperative day. A summary of this paper was presented at the 27th Kansai Local Conference of the Japanese Association for Thoracic Surgery, held in Nagoya on June 27th, 1986  相似文献   

20.
Surgical treatment of cardiac fibroma is rare in patients with left ventricular noncompaction (LVNC). Although several case reports regarding cardiac fibroma have been published, resection in a patient with LVNC has not been described. Here, we describe the surgical treatment of left ventricular fibroma in a child with LVNC. We resected a cardiac fibroma in a 10‐year‐old boy with LVNC to control ventricular arrhythmia. Partial resection with careful tumor dissection was performed to avoid endocardial damage and entering the ventricular cavity. The postoperative course was uneventful, and the patient remains asymptomatic without heart failure or arrhythmia. Surgical excision of cardiac fibroma can be performed safely with excellent results, even in a child with LVNC.  相似文献   

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