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PubMed1993

Primary repair and autotransplantation of cardiac valves.

The aortic valve is a beautifully designed and balanced structure with precise opening and closing mechanisms. Its design probably cannot be improved upon by man-made mechanical devices, no matter how ingenious. It is logical to use human valves as replacements because of their superior structural configuration. Their chief difficulties are in the troubles of the learning curve of the surgeon to achieve a competent mechanism and the hazard of infection. The pulmonary autograft or translocation of the pulmonary valve to the aortic position offers many advantages, and the long-term results are good. Conservative repair and reconstruction of the aortic valve are increasing in popularity but have a relatively limited application. The mitral valve has a less precise and more adjustable type of mechanism and generous leaflet coaptation. These features make it more amenable to repair, as demonstrated in the clinical series of the technique. Repair is clearly preferable to replacement at present. The tricuspid valve is eminently suitable for reconstruction, but late results are not very good. The disappointing outcome, however, reflects more the severity of underlying cardiac pathology than the effectiveness of the repair.

Heart Valves↗
PubMed1997

Comparison of frequency of left atrial thrombus in patients with mechanical prosthetic cardiac valves and stroke versus transient ischemic attacks.

Transesophageal echocardiography performed in a group of 36 patients who had a first cerebral embolic event after implantation of a mechanical cardiac valvular prosthesis revealed that stroke is associated with the presence of left atrial thrombi more frequently than transient ischemic attacks. Intracardiac embolic sources other than thrombi are possibly related more often to the latter type of cerebral embolism in this patient population.

Aged↗
PubMed2004

[Reversible cardiac valve abnormalities with pergolide treatment].

We report the case of a parkinsonian patient treated by pergolide who developed aortic and mitral regurgitations and pulmonary hypertension. When she stopped the medication, the cardiac symptoms disappeared. Retroperitoneal and pleural fibrosis have been described with pergolide but never valvulopathy until 3 cases reported in December 2002.

Aged↗
PubMed1978

Cardiac valve replacement in patients over 65 during a 10-year period.

From 1967 through 1976, 754 adult patients were subjected to open heart procedures for acquired valvular disease at the University of California, San Francisco, 104 of whom were 66 years of age or over (mean = 70 years). The operative mortality of 15.0% in the elderly group did not differ significantly from that of 14.3% in the entire adult series for the 10-year period. Mortality was consistently higher in combined procedures (multiple valve replacement and valve replacement with coronary grafting). Since the introduction, in 1973, of hypothermic hyperkalemic coronary washout for intraoperative protection of the ischemic myocardium, the hospital mortality rate has decreased to 8.1% overall, 6.0% for isolated aortic valve replacement and 0% for isolated mitral valve replacement in patients over 65. Moreover, the long-term survival following aortic and mitral valve replacement in this series appears to approximate the survival curve of the normal population of the same age. This experience suggests that cardiac surgery has become safer for all patients during the past 10 years and that operative mortality is related primarily to the type and severity of disease rather than to age.

Age Factors↗
PubMed1994

Subclinical embolism in patients undergoing cardiac valve implantation and coronary artery bypass surgery.

Patients undergoing prosthetic valve insertion and coronary artery bypass surgery were examined with transcranial Doppler ultrasound, recently shown to be capable of detecting continuing subclinical emboli in patients with embolic sources. In 30 patients examined at least 1 year after valve surgery, and in whom warfarinisation was stable within defined limits, 20 of 24 patients (83%) with mechanical valves and 3 of 6 patients (50%) with porcine valves had embolic signals. In a serial preoperative and postoperative study in a further 30 patients, of whom 29 had native or bioprosthetic valves, only the one patient with a previous mechanical mitral valve prosthesis had embolic signals preoperatively. The incidence of embolic signals increased to 9 (30%) on the first postoperative day, and 20 (67%) on day 5. In a similar serial study in 25 patients undergoing coronary bypass surgery, 8 (32%) had preoperative embolic signals, which were explicable by cardiac and/or carotid disease in 6 cases. The embolus signal incidence and count did not increase postoperatively in this group. No embolic signals were found in 15 volunteer controls. The results indicate that prosthetic valves cause continuing microembolisation, detectable by transcranial Doppler; coronary artery bypass cases may have incidental embolic signals which are unaffected by cardiac surgery. This new application of Doppler ultrasound may improve the clinical assessment of embolic risk of new prosthetic valve types and deserves further examination.

Adult↗
PubMed1993

Time course of hemodynamic changes and improvement of exercise tolerance after cardioversion of chronic atrial fibrillation unassociated with cardiac valve disease.

This study prospectively assessed the time course, magnitude and mechanism of the hemodynamic changes after restoration of sinus rhythm in patients with chronic atrial fibrillation (AF) unassociated with valvular disease. Severe cardiac dysfunction may occur after chronic supraventricular tachycardia in patients with and without underlying cardiac disease. Improvement may follow abolishment of the arrhythmia or adequate slowing of the ventricular rate. Eight patients were studied with a mean previous duration of AF of 10 +/- 9 months. Ejection fraction, exercise capacity and the atrial contribution to the left ventricular filling (only during sinus rhythm) were studied before cardioversion, after cardioversion and 1 week, 1 month and 6 months thereafter. A significant improvement in ejection fraction from 36 +/- 13 to 53 +/- 8% (p < 0.05) occurred at 1 month after cardioversion. Concomitantly, peak oxygen consumption had increased at 1 month, from 20.1 +/- 7 to 25.2 +/- 6 ml/min/kg (p < 0.05). Thereafter, no further improvement in hemodynamic parameters occurred. The atrial systole improved already at 1 week (from 3 +/- 5 to 16 +/- 11%, p < 0.05) and remained unchanged thereafter. Thus, restoration of sinus rhythm was associated with a delayed improvement in ejection fraction and maximal exercise capacity, preceded by an early restoration of atrial contractility and an acute slowing of the heart rate. The discrepancy in time course of restoration of atrial and ventricular function parameters suggests that an intrinsic left ventricular cardiomyopathy is present in patients with AF.

Aged↗
PubMed1981

Measurement and distribution of flexibility in cardiac valve support frames.

Bioprosthetic heart valve support frames of three basic designs were injection moulded in four sizes using five plastic materials and the flexibility of each individual frame post measured. There was a regular pattern of distribution of flexibility of each individual frame post measured. There was a regular pattern of distribution of flexibility in these frames in spite of the fact that within each group of frames the dimensions of each were identical. Identically produced frames of different size showed an alteration in this pattern of flexibility and even small variations in the design of the frames resulted in marked changes in both the degree and distribution of flexibility. The plastic chosen also affected the degree of flexibility obtained also affected the degree of flexibility obtained. The flexibilities of three commercially-available support frames were also measured. The Carpentier-Edwards bioprosthesis was found to have one post more flexible than the other two in a regular pattern inherent in the design of the frame. The Angell-Shiley valve frame, because of its irregular design, displayed a totally irregular pattern. There was a regular pattern of distribution of flexibility in the Hancock porcine bioprosthesis frame. It is concluded that such differences in flexibility are a consequence of frame design, variations in the crystal structure of the plastic materials during manufacture and the choice of plastic used.

Cardiac Surgical Procedures↗
PubMed1985

Penetration of penicillins into cardiac valves and auricles of patients undergoing open-heart surgery.

Prophylactic use of antibiotics in open-heart surgery for insertion of prosthetic valves is common, because of the serious consequences of postoperative staphylococcal infections, most notably prosthetic valve endocarditis. To ensure effective antibiotic cover during surgery, the penetration of cloxacillin and benzylpenicillin into the heart muscle and valves was studied intraoperatively. Both antibiotics were given intravenously (respective initial doses 2 g and 6 g) at induction of anesthesia to ten patients undergoing replacement of aortic or mitral valve, and the same doses were repeated after 4 hours. Serial serum samples and tissue samples from the right atrial auricle and the excised heart valve were analyzed for antibiotic concentrations. The mean serum concentrations of cloxacillin were 204 +/- 93 mg/l 10 min after the initial dose and less than or equal to 26 mg/l 30 min before the second dose. The corresponding values for benzylpenicillin were 323 +/- 145 and 43 +/- 24 mg/l. The cloxacillin concentrations in the auricle just before the start of extracorporeal circulation ranged from 4.5 to 80 mg/kg and (later) in the excised heart valves they were 8.5 to 45 mg/kg. The benzylpenicillin range was 16 to 153 mg/kg in auricle and 13 to 87 mg/kg in valve tissue. The authors conclude that the employed doses of the penicillins are adequate cover against the staphylococci which may be implicated in postoperative infections.

Cardiac Surgical Procedures↗
PubMed2001

Intratumoral hemorrhage from a posterior fossa tumor after cardiac valve surgery--case report.

A 53-year-old woman suffered intracranial hemorrhage from a cerebellar tumor several days after aortic valve replacement. Surgical intervention was not performed because the patient refused blood infusion for religious reasons (Jehovah's Witness). Instead, the anticoagulation therapy was interrupted for a week, and the patient was conservatively treated with administration of mannitol and steroid. The anticoagulation therapy was restarted 7 days after the hemorrhage. The intratumoral hemorrhage did not recur, and no systemic embolism occurred. The tumor was treated with gamma knife radiosurgery 6 weeks after the hemorrhage, under the radiological diagnosis of meningioma. Anticoagulation therapy is routinely used for patients following cardiac surgery to decrease the risk of thromboembolic complications, but also increases the risk of hemorrhagic events which often involve the central nervous system. Temporary discontinuation of anticoagulation therapy is an option for intratumoral hemorrhage in patients with replacement heart valves, and patients with known brain tumors should be informed about the risk of intracranial hemorrhage before cardiac surgery.

Adrenal Cortex Hormones↗
PubMed2004

[Pericardium and cardiac valves: value of MRI and Multislice CT].

Color Doppler echocardiography has limitations, particularly in the assessment of valvular regurgitation and pericardial diseases. MRI, with the help of three dimensional morphologic data, dynamic acquisitions with cine techniques and functional evaluation with flow sensitive techniques can be envisioned as a complementary noninvasive procedure able to provide the complete information required for planning therapeutic options. Qualitative as well as accurate and reproducible quantitative information (volume measurements, cardiac function and flow velocity profiles) are unique for the evaluation of the severity of valve or pericardial diseases. Multislice CT is unique in precisely demonstrating valvular and pericardial calcifications. This article reviews both imaging techniques used in assessing valvular and pericardial disease and discusses the advantages and limitations of these techniques in current clinical applications.

Heart Diseases↗
PubMed1995

[Fibrinolytic inhibitors and prevention of bleeding in cardiac valve surgery. Comparison of tranexamic acid and high dose aprotinin].

In order to assess the effects of tranexamic acid in comparison to the high dose regimen of aprotinin recommended by Royston and considered to be the reference in postoperative bleeding in cardiac surgery, 35 consecutive patients were randomised to two groups according to the product prescribed. The global postoperative bleeding was comparable in the two groups (p = 0.49). One surgical reoperation for haemostasis was required in the reference group. There was one case of renal failure in the same group due to cardiac failure. No thrombotic complications were observed. Platelet function, as judged by the bleeding time and platelet aggregation to ristocetin, was the same in the two groups. The D-dimers remained low in both groups, reflecting the absence of intravascular coagulation and fibrinolysis. Tranexamic acid was as effective and as safe as high dose aprotinin. These two substances, in addition to their fibrinolytic inhibitory activity, conserved platelet protection by blocking the action of plasmin. These results seem to justify the preventive use of tranexamic acid from the moment of skin incision, especially in reoperation.

Adult↗
PubMed1986

Noninvasive evaluation of cardiac valve prostheses.

Noninvasive techniques are particularly helpful in evaluating the function of mechanical prostheses and tissue valves. Combined phonocardiography with M-mode echocardiography, cinefluoroscopy, and Doppler echocardiography are the most useful noninvasive techniques in differentiating normal from abnormal metallic prosthetic valve function. The intensity of the opening and closing clicks and associated murmurs will depend on the type of prosthetic valve, the heart rate and rhythm, and the underlying hemodynamic status. Arrhythmias and/or conduction disturbances may produce motion patterns that mimic the echocardiographic signs of malfunctioning prosthetic valves. Two-dimensional echocardiography is of limited help in assessing patients with metallic prosthetic valves because of reverberating artifacts and side lobe echoes. However, 2-D echo is extremely useful in excluding underlying left ventricular dysfunction. In addition, 2-D echo allows the determination of the precise alignment of the prosthetic valves so that optimal M-mode evaluation of the disc or poppet motion can be undertaken. Two-dimensional echocardiography also allows diagnosis of pericardial effusion and exclusion of other valvular abnormalities. Differentiation of thrombus formation or tissue ingrowth from paravalvular regurgitation or dehiscence is possible by echophonocardiography, Doppler echocardiography, and cinefluoroscopy. Doppler echocardiography is the most sensitive noninvasive technique in diagnosing paravalvular leaks. In addition, significant obstruction across a prosthetic valve can be determined by calculation of maximal gradient across the obstructed orifice using Doppler echocardiography. The differentiation between "benign physiological regurgitation" from true "pathological regurgitation" by Doppler is not always possible. Disc variance is a potentially serious and lethal problem with the older Beall valves and can be detected readily by a combination of echophonocardiography, cinefluoroscopy, and Doppler echocardiography. With regard to bioprosthetic valves, 2-D echo is superior to M-mode in detecting primary valve failure. In addition, detection of vegetations, valve alignment, ring and individual leaflet motion can be readily accomplished by 2-D echo. When considering the value of noninvasive techniques in prosthetic valve function, it is essential to recognize that the patients must serve as their own control in the follow-up assessment.

Arrhythmias, Cardiac↗
PubMed1996

In vitro flow dynamics of a new mechanical cardiac valve prosthesis--"tricusp".

The hydrodynamic performance of a newly developed JCL-trileaflet mechanical heart valve prostheses (Tricusp) was measured and compared with some of the currently most used heart valve prostheses types. All experiments were performed in an electrohydraulic, computer-controlled pulse duplicator simulating the left side of the human circulatory system. Testing conditions were set according to a Food and Drugs Administration interlaboratory comparison protocol, with cardiac outputs 3.0, 4.5, 6.5 or 8.0 l/min and a constant heart rate of 70 beats/min. Mean systolic pressure differences, volume and energy losses, dimensionless pressure losses and energy loss coefficients were calculated from the recorded pressure, volume and flow tracings. The results with the Tricusp valve were found to be as good, or even better than those with the currently most used commercially available bileaflet valves.

Heart Valve Prosthesis↗
PubMed1997

The Biomed caged-ball cardiac valve prosthesis. A study of 120 implants.

The purpose of this study was to report our experience with 120 prosthetic valves implanted in 105 patients over an 8-year period. Their preoperative status was compared at an average follow-up period of 4 years (range 1 to 6 years) with the postoperative results. We conclude that the Mexican-made valves (Biomed) meet the highest international quality standards: they are well tolerated by the patients; their performance is excellent and no postoperative dysfunction of the valves was ever detected. The few complications observed were no different from those reported for foreign ball-caged valves. Finally, most of our patients showed a marked improvement postoperatively.

Actuarial Analysis↗