Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Assisted Circulation”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 289 records · Page 16Linked to original sources
PubMed2001

[Assisted circulation II--systems for intermediate and long-term mechanical circulatory support].

The concept of artificial circulatory support has been established almost 200 years ago. It has only been within the last four decades that physicians and engineers have developed mechanical assist devices that can temporarily support the circulation until the native heart recovers from a reversible injury. In patients who do not regain native heart function, long-term circulatory support or permanent replace (biologically--heart transplant or permanent mechanical circulatory support) is indicated. In this paper we describe the devices (ABIOMED BSV 5000, Thoratec, HeartMate, Novacor and CardioWest TAH), that are in current clinical use for intermediate and long-term mechanical circulatory support.

Assisted Circulation↗
PubMed1997

Technical standards for medical devices. Assisted circulation devices.

The steep rise in the clinical use of high technology biomedical devices and materials, involving multidisciplinary competencies, points out the problem of mutual standards defining, first of all, functional characteristic and tests able to characterise and qualify devices, materials and minimal safety requirements both for patients and operators. Standards defined by consent of the parties or by law are used to this aim. Fast technical development in specific sectors produces besides lack of rules, which must be quickly filled up. The aim of this paper is both the presentation of the approach to problems related to technical standards for biomedical devices and the presentation of the set up of a technical standard for mechanical heart assist devices.

Assisted Circulation↗
PubMedDate not supplied

[Abdominal compression as a method of resuscitation and assisted circulation].

Experiments on animals have been carried out to investigate the hemodynamic changes during manual abdominal compression (AC) under conditions of heart fibrillation and acute heart failure. The possibility to increase the efficacy of left ventricular bypass (LVB) has been studied. Manual AC enhanced the pressure and blood flow in low-pressure compartments and increased aortic systolic and diastolic pressure. It has been also noted that LVB efficacy was increased in simultaneous assisted perfusion and abdominal compression. The first clinical data confirm the experimental findings.

Abdomen↗
PubMed1991

[Assisted circulation with centrifugal pump for cardiogenic shock after extracorporeal surgery].

A 59 year old woman with aneurysm of the left ventricle anterior wall developed heart failure, class III-IV (NYHA). The radioisotopic angiography showed left ventricular function impairment, ejection fraction of 16% and the aneurysm. She was submitted to aneurysm correction with bovine pericardium patch. In spite of technically successful cardiac surgery, the patient cannot be weaned from cardiopulmonary bypass with maximal pharmacological therapy and intra-ortic balloon pump. Then, we used Biomedicus centrifugal pump for left ventricular assistance. Cannulation was made by aorta and left atrial appendage. Myocardial function evolution was accompanied by hemodynamic parameters and by intra-esophagic echocardiography. The patient was assisted during 42 hours. After this time, assist cannulas were removed in operating room without difficulty. She was submitted to another radioisotopic study on the 50th post-operative day and ejection fraction was 24%. She was discharged from hospital at 52th post-operative day. Nowadays she is in NYHA class II at third post-operative month. More frequent utilization of circulatory assistance devices will reduce global mortality from cardiac surgery and improve safety in surgery of severe cardiac disease.

Assisted Circulation↗
PubMed1995

Reduction of haemorrhagic complications during mechanically assisted circulation with the use of a multi-system anticoagulation protocol.

Two different anticoagulation protocols were used in 49 consecutive patients mechanically supported either for bridge to transplantation (11) or for recovery of myocardial function after cardiac surgery (35). In 46 patients a Biomedicus centrifugal pump was used and in 3 patients a Pierce-Donachy ventricles. Mechanical support was provided to the left ventricle in 14 patients, to the right ventricle in 6 and to both ventricles in 12 patients; an extra-corporeal membrane oxygenator (ECMO) support was used in 17 patients. Thirty-seven males and 12 females, aged 0.2 to 58 years, were supported for an average time of 6.3 days (range 1-43). Anticoagulation was either based on a continuous infusion of heparin in the first 27 patients (group A) or on a multi-system therapy ("La Pitié" protocol) in the other 22 patients (group B). Overall survival rate was 47%. Patients in group A had a 30% (8/27) survival rate, whereas in group B a 68% (15/22) survival rate was observed (p = 0.006). Transplantation and ventricular assist device (VAD) removal was successfully obtained in 59% (16/27) and 91% (20/22) of patients in group A and group B respectively (p = 0.05). Significant bleeding occurred in 21 patients (81%) in group A and in 2 (9%) of group B (p = 0.001). In these patients bleeding averaged 230 +/- 231 ml/kg in group A versus 55 +/- 18 ml/kg in group B (p = 0.001). Surgical revision was necessary for cardiac tamponade or persistent bleeding in 12 patients of group A (25 procedures: mean 0.9/patient) and in 3 patients of group B (one each patient: mean 0.1/patient) (p = 0.01). Infection, thrombo-embolism and brain hemorrhage were also less frequent in group A than in group B. Our data suggest that the "La Pitié" protocol provides a better control of bleeding than the conventional heparin infusion in patients receiving assist device. this reduction in thrombo-hemorrhagic complications might improve the results of mechanical circulatory support.

Adolescent↗
PubMed1984

[Method of devising a muscle pump for assisted circulation].

The authors have proposed a model of the blood pump from the skeletal automuscles of the body for carrying out aortal counterpulsation under experimental conditions. The pump is run by means of direct electric stimulation of the muscle. Have demonstrated that it is possible in principle to design a completely implanted small system of aortal counterpulsation.

Assisted Circulation↗
PubMed2003

Anesthetic management for clipping a giant basilar artery aneurysm with moderate hypothermia, extracorporeal circulation assistance, and propofol infusion.

A 65-year-old female patient underwent surgery to clip a giant basilar artery aneurysm with closed-chest extracorporeal circulation using femorofemoral bypass. Moderate hypothermia (27 degrees C-30 degrees C), retention of spontaneous circulation, and propofol infusion (3-5 mg. kg(-1). h(-1)) were used under general anesthesia. Blood outflow via femoral vein was sufficient to maintain cardiopulmonary bypass and to induce hypothermia. Hemodynamics were controlled with dopamine and noradrenaline. In this case, extracorporeal circulation under moderate hypothermia was used to assist rather than substitute for spontaneous circulation, and spontaneous circulation was maintained at all times. We think that this method had advantages over deep hypothermic circulatory arrest with regard to intraoperative risks and postoperative complications.

Aged↗
PubMed1985

Experimental model of right ventricular failure with heterotopic heart transplantation for assisted circulation.

In 20 acute experiments on 40 mongrel dogs ranging in weight from 15 to 20 kg, a heterotopic heart transplant was implanted into the chest of the recipient with experimentally induced right ventricular failure. A detailed description is presented of the operative technique in acute and chronic experiments. Haemodynamic findings attest to the efficacy of the work of the transplant, the right ventricle of which is able to take over most of the work of the right ventricle of the recipient.

Animals↗
PubMed1983

Assisted circulation in cardiac and respiratory insufficiency.

Intra-aortic counterpulsation with a balloon pump (IABP) was used in 63 patients with cardiogenic shock, heart failure after surgery with artificial circulation, internal lacerations of the myocardium, or unstable angina. It was found that the IABP was most efficient in conditions related to myocardial ischemia. Use of arteriovenous perfusion (in 11 patients) or artificial ventricles is indicated in severe perturbations of the pumping function of the heart. As experience has shown, cardiologic and heart surgery patients usually have multiorgan insufficiency. For this reason, it is necessary to use other artificial organs in complex treatment: artificial lungs, kidneys, livers, etc.

Assisted Circulation↗
PubMed1979

Peripheral hemodynamics in assisted circulation with intra-aortic balloon pumping in patients with cardiogenic shock.

Seven patients treated for cardiogenic shock were studied with and without intra-aortic balloon pumping (IABP). Calf and forearm blood flows were determined with a Dohn plethysmograph and arterial pressures were registered intra-arterially and in the great toe and thumb with the cuff method. During IABP, an augmented flow was registered in the arms and legs and accurate arterial BPs could also be determined from the extremities. The findings demonstrate a beneficial effect of IABP on peripheral flow, expecially in patients who could be weaned off the pump.

Aged↗
PubMed1975

[Assisted circulation. The effect of cardio-synchronous peripheral arterio-arterial counterpulsation on perfusion and metabolism in the area of acute transmural myocardial ischemia].

After establishing a model of ischemia, perfusion in the ischemic area was considerably disturbed. Examination by means of 133xenon-clearance after intramyocardiac injection showed strongly delayed flowing-off compared with controls. Counterpulsation accelerates the flowing-off (perfusion). Untreated control animals reveal after inducing the model ischemia a crucial decrease of ATP concentration and an excessive increase of lactate concentration in the ischemic area. Counterpulsation may inhibit further decrease of ATP in the ischemic area.

Adenosine Triphosphate↗
PubMedDate not supplied

The spindle pump. Development of a nonpulsatile blood pump for assisted circulation.

The spindle pump is a combined working nonpulsatile blood pump, i.e., a centrifugally propelling device. This special concept was chosen to tackle the main problems of nonpulsatile pumps, such as thromboembolic complications, sealing difficulties, and traumatic hemolysis. The first two of these problems were relatively simple to solve compared with the third problem--traumatic hemolysis. Various modifications and constructive steps of the spindle pump were necessary to keep stress on blood components within adequate limits. The actual prototype--tested in three acute experiments and eight experiments with a longer pumping duration (the longest lasting 63 hours)--is described in extenso, and its development is discussed.

Animals↗
PubMedDate not supplied

[Role of the arterial reservoir during assisted circulation in acute heart failure].

The role of "arterial reservoir" (AR) has been assessed experimentally in 20 mongrel dogs during the onset of acute heart failure (AHF) and in left ventricular bypass (LVB). The criteria evaluating AR function were as follows: diameter and volume of aorta filling (dA; VA), aortic wall distensibility (D). Va in the range of BPm 30.4 to 171 mm Hg changed from 12.62 to 49.32 ml, i.e. two-three-fold. D at maximum and minimum BRm values decreased by 10 and more times. A direct correlation between relative Va and da changes with a coefficient 2 has been observed in any aortic section. BPm (but not BPsy st or BPdia st which characterizes a degree of "tense" AR filling can serve as an adequate index of LVB efficacy.

Acute Disease↗
PubMed1978

[Treatment of early post-infarction ventricular aneurysms by assisted circulation and surgery].

Ventricular aneurysm formation in the 3 months following transmural myocardial infarction is rare but may cause serious complications. Cardiac failure and/or ventricular arrhythmias resistant to medical treatment are indications for ventricular resection. The operative mortality is high in this group of patients. 8 patients with ventricular aneurysms of average volume (124 +/- 117 ml/m2) and very impaired left ventricular function (EF : 21 +/- 10%, akinesia : 53 +/- 10%) were operated on with two early deaths and one death in the 7th post operative month. The long term clinical result was satisfactory in the surviving patients, and confirmed by haemodynamic investigation in two of them. The benefical effects of intra-aortic balloon pumping, used preoperatively in all patients, and associated myocardial revascularisation procedures performed in some of them are discussed.

Aged↗
PubMed1983

Development of methods of assisted circulation with artificial heart ventricles.

A comparative study of two methods of bypassing the heart with artificial ventricles (AV) was conducted: left atrium-aorta and left ventricle-aorta. The following factors permit left ventricular bypass to compete successfully with left ventricle-aorta bypass: creation of perfected pumps with low input impedance, use of materials with high resistance to thrombus formation for preparation of the AV and main connecting lines, and development of optimum methods of anticoagulant, disaggregation, and cardiac therapy so that there is no danger of thrombosis and hemorrhage, either experimentally or clinically. Thrombosis was the primary cause of death in only one case in a series of experiments on 15 calves with AV connected according to the atrium-aorta scheme. The positive changes in hemodynamics were approximately the same with the two methods.

Animals↗
PubMed1978

[Assisted circulation with the heart-lung machine after cardiosurgical interventions: one year's experience with intra-aortal counter-pulsation with the heart-lung machine after cardiosurgical operations is reported (author's transl)].

In the period from September 1976 to 1977, aortic or mitral valve replacement was performed in 84 and 34 patients respectively. Cardiogenic shock occurred during or immediately after the operation in 3 and 2 patients respectively (= 8.8% and 2.4%). In spite of the use of intra-aortal counter-pulsation, none of the patients survived the acute event. During the same period, 8 (= 5%) out of 113 patients who had undergone coronary surgery needed intra-aortal counter-pulsation. 4 of them survived the acute left heart failure and at the present time are clinically healthy (N.Y. Heart Association Class II).

Acute Disease↗