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Cornelia Piper

Publications and source records attributed to Cornelia Piper.

At least 19 recordsLinked to original sources

Drug insight: an overview of current anticoagulation therapy after heart valve replacement.

Vitamin K antagonists, such as warfarin, are the gold standard approach for the long-term anticoagulant therapy of patients with mechanical heart valves. Management decisions are, however, based predominantly on expert consensus and on data from nonrandomized, follow-up studies, which have inherent limitations in their methods. Low-intensity anticoagulation therapy provides protection against thromboembolic complications in patients with most types of modern prosthetic heart valve. The addition of low-dose aspirin is safe if international normalized ratio values below 3.5 are maintained. A combined regimen should be considered in high-risk patients and those with coexistent coronary artery or cerebrovascular disease, and in patients who have suffered a thromboembolic event despite a therapeutic international normalized ratio. Thromboprophylaxis with unfractionated or low-molecular-weight heparins is restricted to specific situations, such as when a patient is intolerant to vitamin K antagonists, when surgical procedures require discontinuation of oral anticoagulation, or when the patient is pregnant. A lack of uniformity across practice guidelines make it difficult to reach treatment decisions. Each patient's preference, expressed after counseling about the risks and benefits of each treatment strategy, and an individual assessment of the patient's risk factors, should guide treatment decisions. At present, new anticoagulant agents such as factor Xa inhibitors do not represent a treatment option for heart valve recipients.

Anticoagulants↗

Thromboembolic and bleeding complications following St. Jude Medical valve replacement: results of the German Experience With Low-Intensity Anticoagulation Study.

STUDY OBJECTIVES: Due to their inherent thrombogenicity, mechanical cardiac valves necessitate lifelong oral anticoagulation. Less intensive oral anticoagulation than recommended earlier might result in a lower incidence of bleeding complications without increasing the embolic hazard significantly. DESIGN: Comparison of three different intensities of oral anticoagulation in a prospective, randomized multicenter design. Three months after valve replacement, patients were randomly assigned to stratum A, international normalized ratio (INR) 3.0 to 4.5; stratum B, INR 2.5 to 4.0; or stratum C, INR 2.0 to 3.5. PATIENTS: Data from 2,735 patients following aortic valve replacement (AVR; n = 2,024), mitral valve replacement (MVR; n = 553), and combined AVR and MVR (n = 158) with the St. Jude Medical (SJM) valve (St. Jude Medical; St. Paul, MN) between July 1993 and May 1999 were analyzed, covering a total follow-up period of 6,801 patient-years. All complications were registered prospectively. MEASUREMENTS AND RESULTS: Fifty-one thromboembolic events (TEs) were documented, resulting in a linearized incidence of 0.75 TEs per 100 patient-years, 22 of which were minor (0.32% per patient-year), 10 were moderate (0.15% per patient-year), and 19 were severe (0.28% per patient-year). Thromboembolism following AVR was significantly lower than after MVR (0.53% per patient-year vs 1.64% per patient-year). Patients reported 1,687 bleeding complications (24.8% per patient-year). The vast majority of bleeding complications (n = 1,509; 22.2% per patient-year) were classified as minor, 140 were classified as moderate (2.06% per patient-year), and 38 were classified as severe (0.56% per patient-year). The clinically relevant incidences of moderate and severe TEs and bleeding complications were not significantly different between the three prespecified INR strata. CONCLUSIONS: The intention-to-treat analysis of the results of the German Experience With Low Intensity Anticoagulation study leads to the unexpected result that despite a sophisticated reporting system, the incidence of moderate and severe TE and bleeding complications was comparably low in all INR strata and more or less within the so-called background incidence reported for an age-related "normal" population. This study supports reexamination of the intensity of anticoagulation in patients with the SJM valve.

Adolescent↗

Recommendations for reporting morbid events after heart valve surgery.

Major reasons for the considerable heterogeneity among published results of heart valve surgery are inconsistency in follow up techniques, reporting systems and classification of adverse events. The present recommendations are intended to harmonize the presentation of clinical material in order to improve comparison of data from different sources for the analysis of pooled data. The quality of an observational study is largely, if not entirely, due to the follow up technique, which may be graded according to six categories: Self-reporting of adverse events/well-being by the patients may be classified 'excellent'; if the information is gathered and re-checked at short-term intervals. Data obtained from in-hospital or outpatient examinations by qualified examiners at least twice a year or other personal contact through qualified examiners may be regarded as 'sufficient', if the results are re-checked by contacting the treating home physician. All other follow up techniques may be regarded as inappropriate. Consequences of complications are entirely dependent on severity and possible sequelae. It is therefore recommended to grade any reported complication according to its severity by utilizing a score system. Embolisms are best categorized by utilizing the performance status scale. Bleeding events may be categorized according to severity as fatal, major (requiring hospital transmission with transfusion, surgery or with permanently increased disability) or minor (not requiring hospital admission, surgery or transfusion). In some cases it will remain unclear whether an event was primarily embolic or hemorrhagic. These complications should be summarized as 'not categorized'. The reporting of morbid events due to thrombosis, embolism and bleeding should go along with information regarding the quality of antithrombotic management.

Anticoagulants↗

An unusual bacterium, Aerococcus viridans, and four cases of infective endocarditis.

Four cases are described of Aerococcus viridans endocarditis with favorable outcome, focusing on the clinical picture. Extracardiac findings (e.g. neurological, renal, musculoskeletal, intra-abdominal) in infective endocarditis (IE) have been recognized more frequently in recent years, and may delay the diagnosis and have a negative influence on the prognosis. Aerococcus viridans, a very rare microorganism causing invasive infections, has been associated with bacteremia, septic arthritis, and especially IE. As expected, the strains isolated were susceptible to penicillins, trimethoprim/sulfamethoxazole, and glycopeptides. Medical therapy was sufficient to cure IE in two patients, while two others required surgical intervention.

Adult↗

Influence of two different reporting systems on counts of thromboembolic and bleeding complications after St. Jude medical valve replacement: results from the GELIA study.

BACKGROUND AND AIM OF THE STUDY: Different standards for the reporting of morbid events and different follow up techniques have a profound impact on reported morbidity after prosthetic valve replacement. Most studies follow the guidelines of The American Association of Thoracic Surgery (AATS) and The Society of Thoracic Surgeons (STS); the present authors' group has now developed an adapted Karnofsky scale which allows a more precise grading of the severity of morbid events. METHODS: The AATS/STS criteria and the adapted Karnofsky criteria were applied to the database of the German Experience with Low-Intensity Anticoagulation (GELIA) study. In a study population of 2,735 patients, GELIA compared three different intensities of oral anticoagulation in a prospective and randomized design. Patients registered morbid events prospectively by means of documentation cards. RESULTS: The overall rate of complications was comparable when utilizing the two classification systems. However, use of the AATS/STS criteria resulted in the counting of fewer bleeding complications, because only major bleedings were recorded. In contrast, the incidence of embolic complications was higher compared to the Karnofsky criteria because all events were counted, irrespective of their severity, while clinically insignificant (transient, reversible within 24 h) events were disregarded when using the Karnofsky grading. CONCLUSION: The adapted Karnofsky criteria provide a precise and easily understandable framework for the assessment of complications, with equal weighting of both hemorrhagic and embolic events.

Adolescent↗

Influence of atypical symptoms and electrocardiographic signs of left ventricular hypertrophy or ST-segment/T-wave abnormalities on the natural history of otherwise asymptomatic adults with moderate to severe aortic stenosis: preliminary communication.

BACKGROUND AND AIM OF THE STUDY: Current guidelines recommend that aortic valve replacement (AVR) is deferred in asymptomatic patients with aortic stenosis until symptoms develop. Classical symptoms include exertional dyspnea, angina pectoris and syncope. The influence of atypical symptoms (dizziness, exertional intolerance, fatigue, palpitations/arrhythmias) and electrocardiographic signs of left ventricular hypertrophy or ST-segment/T-wave abnormalities on the natural course of the disease is unknown. METHODS: The clinical course of 100 patients with a preliminary diagnosis of asymptomatic aortic stenosis with respect to clinical signs and symptoms mentioned above was examined. All patients underwent serial echocardiographic examinations with calculation of aortic valve area by the continuity equation. RESULTS: Two patients died during a mean follow up period of 34 +/- 32 months (range: 1-116 months). There were no peri- or postoperative deaths. Seven patients with hemodynamically severe aortic stenosis and concomitant atrial fibrillation, four with classical symptoms after re-evaluation, and five with left ventricular dysfunction underwent short-term AVR and were excluded from any subsequent analysis. In total, 84 patients were either entirely asymptomatic (n = 57; group A) or had atypical symptoms (n = 27; group B). Of these patients, 18 underwent AVR before onset of classical symptoms for various reasons, and 21 were treated medically. The remaining 15 group B patients exhibited classical symptoms significantly earlier than the remaining 30 group A patients (15 +/- 7 versus 35 +/- 24 months; p < 0.002). Aortic valve area tended to decrease more rapidly in group B patients than in group A patients (-0.16 +/- 0.12 versus -0.11 +/- 0.07 cm2 per year; p = 0.053). Clinical and hemodynamic progression were further increased if additional electrocardiographic abnormalities were present. CONCLUSION: Both atypical symptoms and electrocardiographic signs of left ventricular hypertrophy/strain shorten the time interval until otherwise asymptomatic patients exhibit classical symptoms of advanced aortic stenosis requiring prosthetic valve replacement.

Adult↗

Modern aspects of antithrombotic treatment: an introduction.

Intracardiac thrombosis and cardioembolisms may have impressive effects on quality of life, prognosis and therapeutic costs in patients with valve disease or replacement devices. Distinct pathophysiological differences exist regarding intracardiac thrombus formation in low-versus high-pressure areas. Important cardiac confounders for low-pressure areas are left atrial geometry and function, including atrial fibrillation or loss of active atrial contraction. In high-pressure areas, flow velocity and shear stress are raised, and this may result in flow turbulence, for example when blood passes a stenotic area. Other major factors which correlate with intracardiac thrombus formation are implantation of polymer material and the degree of endocardial damage resulting for example, from infective or rheumatic endocarditis. Because of the interaction of platelets and the plasma clotting system, a combination of oral anticoagulation therapy and antiplatelet drugs should prevent more thromboembolic events than might anticoagulation alone. Recent studies in patients with prosthetic heart valves have indicated a positive risk-benefit profile if low-dose antiplatelet drugs are added to moderate intensive oral anticoagulation therapy. Thromboembolic events and bleeding complications due to oral anticoagulation therapy are accepted key parameters to demonstrate the superiority of one replacement device over another. However, there is no consistent system for reporting morbid events. In order to organize low and narrow target INR ranges, point-of-care patient self-testing modalities have been introduced and used effectively in large sample sizes. In the near future, some promising new drugs--including direct thrombin or factor Xa inhibitors with broader therapeutic ranges and thus fewer side effects--will become available. The test for these drugs will be their potential to prevent intracardiac thrombosis and cardioembolism in a patient population which is under significant risk.

Anticoagulants↗

Improvement of oral anticoagulation therapy by INR self-management.

Thromboembolic complications after valve replacement are significantly reduced if the INR is increased from 1.0 to 2.0. Hemorrhagic events increase exponentially with more intensive oral anticoagulation. In INR (patient) self-testing (PST), patients self-check their INR after being appropriately educated and supplied with a coagulometer. Patients contact their home physician if the actual INR tends to run outside an individually defined target INR corridor for correction. For patient self-management (PSM), subjects are trained to self-test their INR and to adjust the anticoagulant dose according to their anticoagulation state. The median difference between self-tested and laboratory-tested INRs was < 5.0%, indicating no significant differences between the two methods. PSM resulted in a significantly more stable oral anticoagulation therapy (OAT), which was the strongest predictor for a low complication rate after valve replacement surgery. Lower rates of thromboembolism (0.9 versus 3.6% per patient-year; pt-yr) and bleeding (4.5 versus 10.9% per pt-yr) (p < 0.001) were seen in PSM subjects than with conventional INR management. A switch from conventional to PSM resulted in a 30% reduction in complication rates in the German Experience with Low Intensity Anticoagulation (GELIA) study. After appropriate education and provision with a handy coagulometer, the vast majority of patients after valve replacement can self-check INRs and adjust the anticoagulant dosage accordingly. PSM results in a significantly more stable oral anticoagulation treatment and consequently in lower incidences of thromboembolic and bleeding events.

Administration, Oral↗

[Congenital heart disease and acquired valvular lesions in pregnancy].

BACKGROUND: In Germany, about 6,000 pregnancies in women with grown-up congenital heart disease or acquired valvular lesions are expected per year. The pregnancy-related physiology is characterized by a 50% increase in plasma volume and a 25% increase in erythrocyte volume. The cardiac output increases by 40% due to 30% increase in stroke volume and 10% increase in heart rate during the first half, and 10% increase in stroke volume but 30% increase in heart rate during the second half of pregnancy. As a consequence of the decrease of systemic vascular resistance, the systolic and, even more, the diastolic blood pressures are reduced during approximately the first 20 weeks of pregnancy. UNCORRECTED CONGENITAL LESIONS: Women with uncorrectable congenital heart disease, congestive heart failure (NYHA III and IV) despite optimized medical treatment after palliative surgery, or pulmonary vascular resistances > 800 dyn x s x cm(-5) should be advised against pregnancy. The presence of congestive heart failure or persistent cyanosis in the mother are the most important predictors of fetal hypoxia. Patients with pretricuspid shunts (e.g., atrial septal defect [ASD]) are at low risk of a hemodynamic deterioration or first onset of arrhythmias. In the rare case of a marked clinical deterioration, catheter-based closing of the shunt is the first-line treatment. Also, ventricular septal defects and persistent ducti arteriosi are usually well tolerated during pregnancy, as they are highly resistant to flow. In some cases, arrhythmias may occur. The prognosis is less favorable, if myocardial compromise has already been present before pregnancy. The fatal complication rate correlates closely with the degree of congestive heart failure. In aortic coarctation, development of severe hypertension, myocardial decompensation, aortic dissection, and cerebral hemorrhage have been reported in 2.3% of cases. To prevent aortic dissection and rupture of cerebral vascular aneurysms, patients should be advised to reduce their physical activity and have their blood pressure controlled closely. If, during pregnancy, a therapeutic intervention is unavoidable, stent placement is the therapy of choice. The maternal complication rate is low in pulmonary artery stenosis. Hemodynamically significant stenoses should be treated before pregnancy. In the rare case of progressive right heart failure or cyanosis during pregnancy, balloon valvotomy is the first-line therapeutic option. CONGENITAL HEART DISEASE WITH PRIOR PALLIATION: Women with incomplete correction of a tetralogy of Fallot or significant residual gradients or shunts carry a particular risk of myocardial deterioration. A maternal hematocrit > 60%, an arterial O(2) saturation < 80%, markedly elevated right ventricular pressures, and the former presentation of syncopes are indicators of a poor prognosis. Fatal complication rates have been reported in 3-17% of cases. Other cyanotic lesions have been linked with a poor maternal and fetal prognosis. A 32% incidence of severe cardiovascular complications (pump failure, thromboembolic events, life-threatening arrhythmias, infective endocarditis) has been reported during 96 pregnancies of women with cyanotic heart disease. In addition, the frequency of abortions, premature birth, fetal distress, and congenital malformation of the child was 57%. ACQUIRED VALVE LESIONS: Mitral stenosis is the lesion that most frequently requires therapeutic intervention during pregnancy, as the transmitral flow increases and time of diastole decreases during pregnancy due to the increase in cardiac output and heart rate. A consequent increase in mean pulmonary artery pressure by approximately 50% and a deterioration by one to two NYHA classes must be expected. While patients with a mitral orifice area > 1.5 cm(2) can usually be treated medically, more advanced mitral stenoses often require percutaneous mitral balloon valvotomy, a procedure with a very low complication rate in experienced centers. A chronic mitral or aortic regurgitation without jeopardized myocardial function is usually well tolerated during pregnancy, as the drop in peripheral vascular resistance results in a favorable left ventricular impedance, which reduces the transmitral regurgitant fraction and improves left ventricular antegrade ejection. Moreover, the increase in heart rate limits diastolic transaortic regurgitation. Hemodynamically advanced aortic stenosis is rare among patients in child-bearing age. The hemodynamic changes during pregnancy result in a decrease of the transaortic flow per time and thus in a decrease of the transaortic pressure loss. On the other hand, myocardial wall stress and oxygen consumption are significantly increased. If aortic valve orifice area is > 1.5 cm(2), the hemodynamic situation is usually well tolerated during pregnancy. In the case of more advanced aortic stenosis, there is a considerable risk of myocardial decompensation. The development of symptoms such as dyspnea, near syncopes or syncopes, and arrhythmias are indicators of a complicated course. If treatment is unavoidable, aortic valve replacement is the therapy of choice. ORAL ANTICOAGULATION: With respect to anticoagulation during pregnancy, there is an ongoing debate about the potential risk and benefit of phenprocoumon, standard heparins, and low molecular heparins. Withdrawal of any anticoagulation results in the most favorable fetal outcome, oral anticoagulation throughout pregnancy in the best prognosis for the mother. An individual approach by an experienced center taking all therapeutic options into account is probably the best strategy.

Female↗

Can progression of valvar aortic stenosis be predicted accurately?

BACKGROUND: It was the aim of the present study to elaborate criteria for the assessment of rapid hemodynamic progression of valvar aortic stenosis. These criteria are of special importance when cardiac surgery is indicated for other reasons but the established criteria for aortic valve replacement are not yet fulfilled. Such aspects of therapeutic planing were mostly disregarded in the past so that patients had to undergo cardiac reoperation within a few years. METHODS: Hemodynamic, echocardiographic, and clinical data of 169 men and 88 women with aortic stenosis, aged 55.2 +/- 15.7 years at their first and 63.4 +/- 15.6 years at their second cardiac catheterization, were analyzed. RESULTS: The progression rate of aortic valve obstruction was found to be dependent on the degree of valvar calcification ([VC] scoring 0 to III) and to be exponentially correlated with the aortic valve opening area (AVA) at initial catheterization. Neither age nor sex of the patient nor etiology of the valvar obstruction significantly influence the progression of aortic stenosis. If AVA decreases below 0.75 cm(2) with a present degree of VC = 0, or AVA of 0.8 with VC of I, AVA of 0.9 with VC of II, or AVA of 1.0 with VC of III, it is probable that aortic stenosis will have to be operated upon in the following years. CONCLUSIONS: The present data indicate that for clinical purposes and planning of valvar surgery the progression of asymptomatic aortic stenosis can be sufficiently predicted by the present aortic valve opening area and the degree of valvar calcification.

Adolescent↗