The course of pregnancy in patients with artificial heart valves

Twenty-five women with prosthetic heart valves (PHV) became pregnant 28 times. Twenty-six of the pregnancies occurred while the patients were receiving oral anticoagulants and these were continued throughout in 25 pregnancies. Dipyridamole or dipyridamole and acetylsalicylic acid were used in 22 pregnancies. Eighteen infants were delivered, one with a congenital corneal leukoma; none had hemorrhagic complications; their psychomotor development was normal. Nine women aborted 10 times, including patients with two PHV, pelvic trauma and self-induced abortion. We could not detect excess anticoagulation in eight of the nine who had spontaneous losses; excess anticoagulation occurred five weeks before an abortion. There were no maternal deaths despite numerous complications; in two women, brain embolism was related to short interruptions of anticoagulation. The details of management are mentioned. We lack enough evidence to suggest routine sterilization, routine interruption of coumarin therapy during pregnancy or routine interruption of pregnancy in women with certain types and models of PHV; however, pregnancy under such conditions, plus antithrombotic therapy, carries a high risk for the product and a potential teratogenic effect. Women with one or two PHV can have children if their management is closely supervised and if extreme care is taken with the use of oral anticoagulants.     

Plasma concentrations of platelet-specific proteins correlated with platelet survival

Relationships between 51Cr platelet survival and plasma concentrations of beta-thromboglobulin (betaTG) and platelet factor 4 (PF4) were analyzed in 91 studies of patients with coronary artery disease. betaTG was significantly correlated with platelet life-span, turnover, and the number of hits in the multiple hit model. PF4 was significantly correlated with life-span and turnover. The most significant relationship involving platelet-specific protein concentrations and life-span estimates was between betaTG and life-span estimated using the multiple hit model (r = -0.39, p less than 0.001). There was a high correlation between betaTG and PF4 (r = 0.62, p less than 0.001), and no improvement could be obtained by combining the measurements of the two proteins in any regression with life-span or turnover. The results indicate that the patients with the shortest platelet survival time in this group tended to have the highest plasma concentration of betaTG and PF4 and thus probably increased in vivo release of betaTG and PF4. They strengthen the claim that these platelet-specific proteins may be indicators of platelet involvement in disease.     

Lower extremity hematoma as a complication of warfarinization in patients with artificial heart valves.

Four cases of lower extremity hematoma in patients undergoing anticoagulant therapy after heart valve replacement are herein reported, with special emphasis on the comparative diagnostic value of ultrasonography and computerized tomography. Although conservative management is sufficient for patients with no neurological impairment, needle aspiration after autolysis of the hematoma, which can be confirmed by CT study, is also recommended.     

Antithrombotic therapy in valvular heart disease and artificial valves

The article summarizes the current recommendations and knowledge for the treatment of patients with artificial valves. The attention is focused on antithrombotic therapy after valve replacement, including possible complications of the treatment, particularly thromboembolic and bleeding complications. We review the procedures when the anticoagulation must be interrupted. The possibilities of improving therapy in patients that require permanent anticoagulation and the outlook for the future are discussed.     

Plasma adenosine concentration during and after dynamic exercise in patients with chronic heart failure

The purpose of this study was to evaluate the changes of plasma adenosine concentration by dynamic exercise in patients with chronic heart failure. We studied six patients with chronic heart failure (heart failure group) and six normal subjects (normal group). A symptom-limited ramp exercise test was performed with subjects sitting upright on a bicycle ergometer. The first exercise test was performed to determine the anaerobic threshold. The second exercise test was performed 2 days thereafter, and blood samples for assay of adenosine, lactate, and norepinephrine were taken from the antecubital vein at rest, during, and after exercise. In the heart failure group, VO₂ at anaerobic threshold and peak exercise was significantly lower than that in the normal group, whereas there was no difference in respiratory quotient at peak exercise between the two groups. There was a significant increase in the plasma adenosine level from the point before anaerobic threshold to 10 minute after exercise in the normal group, whereas a mild increase in plasma adenosine level was observed only 15 minute after exercise in the heart failure group. The change of plasma adenosine was significantly smaller in the heart failure group (p<0.05). There was a significant relationship between plasma adenosine and lactate levels (r=0.42, n=48,p<0.01). These findings indicate that production of adenosine is decreased in patients with chronic heart failure, and vasodilation of exercising muscle induced by adenosine might be impaired during exercise.     

Salmonella bacteremia in patients with prosthetic heart valves

During 1982 and 1983, five patients with prosthetic heart valves and documented Salmonella bacteremia were admitted to the Instituto Nacional de Cardiologia in Mexico City. The clinical and microbiologic features in this group of patients are described, as well as the therapeutic implications when Salmonella bacteremia is present in patients with heart prostheses. None of the patients had evidence of infectious endocarditis; however, all received prolonged parenteral antimicrobial therapy for at least four weeks with ampicillin or chloramphenicol, with excellent clinical response.     

Platelet survival in patients with prosthetic heart valves

Chromium-51 platelet survival studies were carried out in 20 patients with a prosthetic heart valve. Only 1 of 10 patients with a prosthetic mitral valve had a significantly shortened platelet survival time, and the mean value of 8.3 ± 0.96 (±1 standard deviation) days was not significantly different from that of normal control subjects (8.9 ± 0.75 days). Four of 10 patients with an aortic prosthesis had a shortened platelet survival time, and the mean value of 7.8 ± 0.10 days in this group differed significantly from the normal control value (P < 0.05). Treatment with aspirin did not appear to alter platelet survival but, when combined with Coumadin therapy, resulted in marked prolongation of bleeding time. Our results do not support the concept that thrombus formation on the prosthesis is the cause of the shortened platelet survival time since thrombus formation is more likely to occur in mitral than aortic prostheses. Reduced platelet survival time secondary to damage by the prosthesis, similar to the problem of hemolysis in red blood cells, is a more likely explanation.     

Antithrombotic therapy in patients with prosthetic heart valves

Anticoagulant therapy is an important component of treatment of patients with prosthetic heart valves. The article contains consideration of specific problems of antithrombotic therapy in patients with various types of prostheses and its tactics in different clinical situations. In the absence of national recommendations on the use of anticoagulants in these patients the authors suggest schemes of management based on recent European and American guidelines.     

Plasma concentrations of platelet-specific proteins and serum thromboxane B2 production in response to treatment with dipyridamole. A pilot study of 27 post-myocardial infarction patients

In the present study 27 post-myocardial infarction patients were treated with Persantin capsules (Depot-Kapseln, sustained release form), containing 200 mg dipyridamole, b.i.d. over a period of 3 weeks. Baseline levels for plasma beta-thromboglobulin (BTG), platelet factor 4 (PF4), and serum thromboxane B2 (TXB2) were obtained on day 0 and subsequently on days 1, 3, 5, 7, 14 and 21. The baseline levels for plasma BTG and PF4 as well as for serum TXB2 significantly exceeded those for a control group consisting of healthy subjects. The plasma values for BTG and PF4 remained unchanged during the whole study period. During the first week of study the levels for serum X TXB2 were unchanged; however, on days 14 and 21 the means for TXB2 dropped significantly. There is experimental work to suggest that dipyridamole may exert an inhibitory effect on platelet thromboxane biosynthesis. The present results support this concept.     

Urinary fibrinopeptide A levels in ischemic heart disease

Because acute coronary thrombosis can cause unstable coronary artery disease, fibrinopeptide A, a reliable marker of coagulation activity, may play a role in the evaluation of unstable ischemic syndromes. A new method of fibrinopeptide A sampling, spot urine normalized to urinary creatinine, was evaluated in patients with stable and unstable angina pectoris and acute myocardial infarction. Serial samples were obtained to characterize the changes in urinary fibrinopeptide A levels over time in patients with ischemic heart disease. Admission values (mean +/- SD) were similar in the control group (3.3 +/- 1.4 ng/mg creatinine) and the stable angina group (3.2 +/- 1.1 ng/mg creatinine) (p = NS). Values in the unstable angina group (5.7 +/- 2.6 ng/mg creatinine) were higher than those in the control (p = 0.008) and stable angina (p less than 0.001) groups. Myocardial infarction admission values (8.4 +/- 10.0 ng/mg creatinine) were higher than those in the control (p = 0.005) and stable angina (p less than 0.001) groups, but not higher than those in the unstable angina group. Peak values (the highest of multiple samples) were higher in the unstable angina group (7.6 +/- 5.9 ng/mg creatinine) than in the stable angina group (4.0 +/- 1.0 ng/mg creatinine) (p = 0.04), but not in the control group (4.5 +/- 1.9 ng/mg creatinine) (p = 0.056). The two patients with unstable angina with the highest peak values subsequently exhibited infarction. Peak values in patients with infarction (44.5 +/- 60.0 ng/mg creatinine) were significantly higher than those in patients with unstable (p = 0.03) or stable (p = 0.002) angina and control patients (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Plasma concentrations of fibrinopeptide A and fibrinopeptide B beta 15-42 in glomerulonephritis and the nephrotic syndrome

Plasma fibrinopeptide A (FPA) and fibrinopeptide B beta 15-42 concentrations were determined by radioimmunoassay in 46 patients with glomerulonephritis and the nephrotic syndrome. An increase in plasma FPA and B beta 15-42 levels was noted in these patients; this increase was marked in the nephrotic patients. There was a positive correlation in these patients between plasma FPA and B beta 15-42 levels. The B beta 15-42/FPA ratio was significantly higher in nonnephrotic patients compared with controls. Intravascular coagulation with subsequent fibrinolysis to regulate fibrin formation may occur in patients. A positive correlation was found between plasma B beta 15-42 level and serum urea nitrogen or serum creatinine concentration, suggesting that plasma B beta 15-42 level is influenced not only by plasmin action, but also by renal dysfunction.