Antiplatelet Therapy and Anticoagulation before, during, and after Acute Coronary Syndrome

Acute coronary syndrome (ACS) remains a major challenge in clinical practice, requiring rapid and effective antithrombotic treatment to mitigate adverse ischemic events while minimizing the risk of bleeding. In recent years, results from several clinical trials addressing this issue through various approaches have substantially improved the treatment landscape for patients presenting with ACS. The emergence of new, potent P2Y12 inhibitors has significantly enhanced thrombotic risk reduction and different strategies for de-escalating and shortening dual antiplatelet therapy (DAPT) have demonstrated promising outcomes in reducing bleeding rates. Furthermore, data from ongoing trials focusing on novel therapeutic agents and investigating alternative treatment strategies to optimize outcomes for ACS patients are expected in the next few years. In this review, we summarize the current knowledge and emphasize the critical role of individualized treatment approaches tailored to patient-specific risk factors and individual clinical scenarios.

Low-density lipoprotein cholesterol reduction with immediate combination therapy of statin and ezetimibe compared to statin monotherapy after percutaneous coronary intervention

BACKGROUND

Current guidelines recommend a stepwise initiation of lipid-lowering therapy after percutaneous coronary interventions (PCI) in treatment-naïve individuals. Patients might benefit from an earlier and stronger low-density lipoprotein-cholesterol (LDL-C) reduction through upfront combination therapies.

METHODS

This retrospective study included patients without previous lipid-lowering therapy undergoing acute or elective PCI with stent implantation between January 2016 and December 2019. Patients initiated on statin monotherapy vs. a combination of statin and ezetimibe were compared. The primary endpoint was an LDL‑C reduction into the target range of < 55 mg/dL at 3 months. The secondary endpoint was the occurrence of major cardiovascular events (MACE).

RESULTS

A total of 204 lipid-lowering therapy naive patients were included, of whom 157 (77.0%) received statin monotherapy and 47 (23.0%) combination therapy. Median LDL‑C levels were higher in patients initiated on combination therapy vs. monotherapy (140 mg/dL, interquartile range, IQR, 123-167 mg/dL vs. 102 mg/dL, IQR 80-136 mg/dL, p < 0.001). The LDL‑C reduction was greater in patients treated with combination therapy vs. statin monotherapy (-73 mg/dL, -52.1% vs. -43 mg/dL, -42.2%, p < 0.001). While the primary endpoint was similar between groups (44.7% vs. 36.1%, p = 0.275), combination therapy significantly increased the proportion of patients achieving the treatment target in the presence of an admission LDL-C > 120 mg/dL (46.2% vs. 26.2%, p = 0.031). The rates of MACE were similar between the two groups (10.6% vs. 17.8%, p = 0.237) at a median follow-up of 2.2 years, IQR 1.46-3.10 years.

CONCLUSION

Immediate initiation of high-intensity statin and ezetimibe treatment might be considered as the default strategy in treatment-naïve patients with high admission LDL‑C undergoing PCI.

The LIPL study: Postprandial lipid profile, inflammation, and platelet activity in patients with chronic coronary syndrome

Background and aims

It is suggested that the changes in atherosclerosis happen mainly under the influence of non-fasting lipids. To date, the studies in the postprandial state were primarily performed on healthy subjects. This exploratory, cross-sectional study investigates the change in lipid profile, inflammation, and platelet activation in patients with different cardiovascular risk profiles in the postprandial state.

Methods

The studied population consists of 66 patients with different cardiovascular risks: patients with a history of the chronic coronary syndrome (CCS) and diabetes mellitus type 2 (DM2) (n = 20), CCS without DM2 (n = 25), and a healthy control group (n = 21). Lipid variables and markers of platelet function and inflammation were assessed during the fasting state and three and 5 h after a standardized fat meal using a standardized oral fat tolerance test (OFTT), a milkshake with 90 g of fat.

Results

Patients with CCS and DM2 were significantly older and had the highest BMI. All patients with CCS were on acetylsalicylic acid, and 95% of CCS patients were on high-dose statins. The absolute leukocyte and neutrophile count increased significantly in the control group during the OFTT in comparison to CCS subjects. There was a significant decrease of HDL and increase of triglycerides during the OFTT, however with no difference between groups. There was no difference in the change of platelet activity between all groups.

Conclusion

This study showed that OFTT leads to an increased postprandial inflammation response in healthy group compared to CCS ± DM2 while there was no change in lipid profile and platelet activity.

Cardiac inflammation associated with COVID-19 mRNA vaccination in patients with and without previous myocarditis

BACKGROUND

mRNA COVID-19 vaccines have been associated with myocarditis in the general population. However, application of gold standard techniques is often missing, and data about patients with history of myocarditis have not been reported yet.

METHODS

We evaluated 21 patients (median age 27, 86% males) for suspected myocarditis after receiving mRNA COVID-19 vaccine. We divided cases with previous diagnosis of myocarditis (PM, N.=7), from naïve controls (NM, N.=14). All patients were investigated thoroughly by cardiac magnetic resonance (100%) with or without endomyocardial biopsy (14%).

RESULTS

Overall, 57% of patients met updated Lake Louise criteria and none fulfilled Dallas criteria, with no remarkable differences between groups. Acute coronary syndrome-like presentation was more frequent in NM with earlier normalization of troponin than PM. NM and PM already healed from myocarditis were clinically comparable, whereas PM with active inflammation had subtle presentation and were evaluated for immunosuppressive therapy modulation. None had fulminant myocarditis and/or malignant ventricular arrhythmia at presentation. No major cardiac events occurred by 3 months.

CONCLUSIONS

In this study, the suspicion of mRNA COVID-19 vaccine-associated myocarditis was inconstantly confirmed by gold standard diagnostics. Myocarditis was uncomplicated in both PM and NM patients. Larger studies with longer follow-up are needed to validate COVID-19 vaccination in this population.

Association of Interleukin-32 and Interleukin-34 with Cardiovascular Disease and Short-Term Mortality in COVID-19

BACKGROUND

Excess cardiovascular (CV) morbidity and mortality has been observed in patients with COVID-19. Both interleukin-32 (IL-32) and interleukin-34 (IL-34) have been hypothesized to contribute to CV involvement in COVID-19.

METHODS

This prospective, observational study of patients with laboratory-confirmed COVID-19 infection was conducted from 6 June to 22 December 2020 in a tertiary care hospital in Vienna, Austria. IL-32 and IL-34 levels on admission were collected and tested for their association with CV disease and short-term mortality in patients with COVID-19. CV disease was defined by the presence of coronary artery disease, heart failure, stroke or atrial fibrillation and patients were stratified by CV disease burden.

RESULTS

A total of 245 eligible patients with COVID-19 were included, of whom 37 (15.1%) reached the primary endpoint of 28-day mortality. Of the total sample, 161 had no CV disease (65.7%), 69 had one or two CV diseases (28.2%) and 15 patients had ≥three CV diseases (6.1%). Median levels of IL-32 and IL-34 at admission were comparable across the three groups of CV disease burden. IL-32 and IL-34 failed to predict mortality upon both univariable and multivariable Cox regression analysis. The two CV disease groups, however, had a significantly higher risk of mortality within 28 days (one or two CV diseases: crude HR 4.085 (95% CI, 1.913-8.725), p < 0.001 and ≥three CV diseases: crude HR 13.173 (95% CI, 5.425-31.985), p < 0.001). This association persisted for those with ≥three CV diseases after adjustment for age, gender and CV risk factors (adjusted HR 3.942 (95% CI, 1.288-12.068), p = 0.016).

CONCLUSION

In our study population of hospitalized patients with COVID-19, IL-32 and IL-34 did not show any associations with CV disease or 28-day mortality in the context of COVID-19. Patients with multiple CV diseases, however, had a significantly increased risk of short-term mortality.

Short dual antiplatelet therapy and dual antiplatelet therapy de-escalation after primary percutaneous intervention: For whom and how

Dual antiplatelet therapy (DAPT) for 6-12 months, followed by lifelong aspirin monotherapy is considered an effective standard therapy for the prevention of thrombo-ischemic events in patients with acute and chronic coronary syndrome (ACS, CCS) undergoing percutaneous coronary intervention (PCI) or after a primarily conservative treatment decision. In ACS patients, the stronger P2Y12-inhibitors ticagrelor or prasugrel are recommended in combination with aspirin unless the individual bleeding risk is high and shortening of DAPT is warranted or clopidogrel is preferred. However, also in patients at low individual bleeding risk, DAPT is associated with a higher risk of bleeding. In recent years, new antithrombotic treatment strategies, such as shortening DAPT followed by early P2Y12-inhibitor monotherapy and de-escalating DAPT from potent P2Y12-inhibitors to clopidogrel by maintaining DAPT duration time, have been investigated in clinical trials and shown to reduce bleeding complications in cardiovascular high-risk patients without negative effects on ischemic events. In this review, we summarize the current knowledge and discuss its implication on future antithrombotic strategies in terms of a personalized medicine.

Neutrophile-Lymphocyte Ratio and Outcome in Takotsubo Syndrome

Background: Takotsubo syndrome (TTS) is an important type of acute heart failure with significant risk of acute complications and death. In this analysis we sought to identify predictors for in-hospital clinical outcome in TTS patients and present long-term outcomes. Methods: In this analysis from the Austrian national TTS registry, univariable and multivariable analyses were performed to identify significant predictors for severe in-hospital complications requiring immediate invasive treatment or leading to irreversible damage, such as cardiogenic shock, intubation, stroke, arrhythmias and death. Furthermore, the influence of independent predictors on long-term survival was evaluated. Results: A total of 338 patients (median age 72 years, 86.9% female) from six centers were included. Severe in-hospital complications occurred in 14.5% of patients. In multivariable analysis, high neutrophile-lymphocyte-ratio (NLR; OR 1.04 [95% CI 1.02−1.07], p = 0.009) and low LVEF (OR 0.92 [0.90−0.95] per %, p < 0.001) were significant predictors of severe in-hospital complications. Both the highest NLR tercile and the lowest LVEF tercile were significantly associated with reduced 5-year survival. Conclusions: Low LVEF and high NLR at admission were independently associated with increased in-hospital complications and reduced long-term survival in TTS patients. NLR is a new easy-to-measure tool to predict worse short- and long-term outcome after TTS.

Prothrombotic Milieu, Thrombotic Events and Prophylactic Anticoagulation in Hospitalized COVID-19 Positive Patients: A Review

The Coronavirus Disease 2019 (COVID-19) pandemic has resulted in significant morbidity and mortality worldwide. Although initial reports concentrated on severe respiratory illness, emerging literature has indicated a substantially elevated risk of thromboembolic events in patients with COVID-19 disease. Pro-inflammatory cytokine release has been linked to endothelial dysfunction and activation of coagulation pathways, as evident by elevated D-dimer levels and deranged coagulation parameters. Both macrovascular and microvascular thromboses have been described in observational cohort and post-mortem studies. Concurrently, preliminary data have suggested the role of therapeutic anticoagulation in preventing major thromboembolic complications in moderately but not critically ill patients. However, pending results from randomized controlled trials, clear guidance is lacking regarding the intensity and duration of anticoagulation in such patients. Herein, we review the existing evidence on incidence and pathophysiology of COVID-19 related thromboembolic complications and guide anticoagulation therapy based on current literature and societal consensus statements.

Multisystem inflammatory syndrome in adults in a young male following severe acute respiratory syndrome coronavirus-2 infection: a case report

Background

Multisystem inflammatory syndrome in adults (MIS-A) is a rare but potentially life-threatening condition that may occur during or in the weeks following severe acute respiratory syndrome coronavirus-2 infection. To date, only case reports and small case series have described typical findings and management of patients with MIS-A. The prevalence of MIS-A is largely unknown due to the lack of data.

Case summary

A 30-year-old male patient presented to the emergency department with new-onset of fever, chest discomfort, macular exanthema, abdominal pain, mild dyspnoea, and coughing. The patient reported a mildly symptomatic recent coronavirus disease-19 (COVID-19). Significantly increased markers of inflammation and a modest increase of cardiac troponin were found upon laboratory work-up at admission. Despite broad-spectrum antibiotics, the patient’s clinical status deteriorated continuously. Cardiac work-up, including echocardiography, coronary angiography, and cardiac magnetic resonance imaging, was done and signs of acute myocarditis with mildly reduced left ventricular systolic function were found. The complex multi-organ symptom constellation facilitated the diagnosis of MIS-A following COVID-19 infection. Besides aspirin, intravenous, continuous hydrocortisone treatment was initiated, resulting in a prompt improvement of symptoms and clinical findings.

Discussion

We report a case of successfully treated MIS-A in the context of COVID-19, which further adds to the existing literature on this rare but clinically significant condition. Our case highlights the necessity of an interdisciplinary approach to correctly diagnose this complex, multi-organ disease and enable fast and appropriate management of these high-risk patients.

Improvement of outcome prediction of hospitalized patients with COVID-19 by a dual marker strategy using high-sensitive cardiac troponin I and copeptin

Background

COVID-19 has been associated with a high prevalence of myocardial injury and increased cardiovascular morbidity. Copeptin, a marker of vasopressin release, has been previously established as a risk marker in both infectious and cardiovascular disease.

Methods

This prospective, observational study of patients with laboratory-confirmed COVID-19 infection was conducted from June 6th to November 26th, 2020 in a tertiary care hospital. Copeptin and high-sensitive cardiac troponin I (hs-cTnI) levels on admission were collected and tested for their association with the primary composite endpoint of ICU admission or 28-day mortality.

Results

A total of 213 eligible patients with COVID-19 were included of whom 55 (25.8%) reached the primary endpoint. Median levels of copeptin and hs-cTnI at admission were significantly higher in patients with an adverse outcome (Copeptin 29.6 pmol/L, [IQR, 16.2–77.8] vs 17.2 pmol/L [IQR, 7.4–41.0] and hs-cTnI 22.8 ng/L [IQR, 11.5–97.5] vs 10.2 ng/L [5.5–23.1], P < 0.001 respectively). ROC analysis demonstrated an optimal cut-off of 19.3 pmol/L for copeptin and 16.8 ng/L for hs-cTnI and an increase of either biomarker was significantly associated with the primary endpoint. The combination of raised hs-cTnI and copeptin yielded a superior prognostic value to individual measurement of biomarkers and was a strong prognostic marker upon multivariable logistic regression analysis (OR 4.274 [95% CI, 1.995–9.154], P < 0.001). Addition of copeptin and hs-cTnI to established risk models improved C-statistics and net reclassification indices.

Conclusion

The combination of raised copeptin and hs-cTnI upon admission is an independent predictor of ICU admission or 28-day mortality in hospitalized patients with COVID-19.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s00392-021-01970-4.

Impact of the COVID-19 pandemic on hospitalizations for acute coronary syndromes: a multinational study

BACKGROUND

COVID-19 has challenged the health system organization requiring a fast reorganization of diagnostic/therapeutic pathways for patients affected by time-dependent diseases such as acute coronary syndromes (ACS).

AIM

To describe ACS hospitalizations, management, and complication rate before and after the COVID-19 pandemic was declared.

DESIGN

Ecological retrospective study. Methods: We analyzed aggregated epidemiological data of all patients > 18 years old admitted for ACS in twenty-nine hub cardiac centers from 17 Countries across 4 continents, from December 1st, 2019 to April 15th, 2020. Data from December 2018 to April 2019 were used as historical period.

RESULTS

A significant overall trend for reduction in the weekly number of ACS hospitalizations was observed (20.2%; 95% confidence interval CI [1.6, 35.4] P = 0.04). The incidence rate reached a 54% reduction during the second week of April (incidence rate ratio: 0.46, 95% CI [0.36, 0.58]) and was also significant when compared to the same months in 2019 (March and April, respectively IRR: 0.56, 95%CI [0.48, 0.67]; IRR: 0.43, 95%CI [0.32, 0.58] p < 0.001). A significant increase in door-to-balloon, door-to-needle, and total ischemic time (p <0.04 for all) in STEMI patents were reported during pandemic period. Finally, the proportion of patients with mechanical complications was higher (1.98% vs. 0.98%; P = 0.006) whereas GRACE risk score was not different.

CONCLUSIONS

Our results confirm that COVID-19 pandemic was associated with a significant decrease in ACS hospitalizations rate, an increase in total ischemic time and a higher rate of mechanical complications on a international scale.

Direct cardiovascular complications and indirect collateral damage during the COVID-19 pandemic : A review

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), puts a heavy strain on healthcare systems around the globe with high numbers of infected patients. Pre-existing cardiovascular disease is a major risk factor for a severe clinical course of COVID-19 and is associated with adverse outcome. COVID-19 may directly exacerbate underlying heart disease and is frequently aggravated by cardiovascular complications, including arterial and venous thromboembolic events, malignant arrhythmia and myocardial injury. In addition to these direct cardiac manifestations of COVID-19, patients with cardiovascular disease face further indirect consequences of the pandemic, as the respective resources in the healthcare systems need to be redirected to cope with the high numbers of infected patients. Consecutively, a substantial decrease in cardiac procedures was reported during the pandemic with lower numbers of coronary angiographies and device implantations worldwide. As a consequence an increased number of out-of-hospital cardiac arrests, late-comers with subacute myocardial infarction and of patients presenting in cardiogenic shock or preshock were observed. Maintenance of high-quality cardiac care by avoiding a reduction of cardiac services is of utmost importance, especially in times of a pandemic.

Mid-regional pro-atrial natriuretic peptide independently predicts short-term mortality in COVID-19

BACKGROUND

Mid-regional pro-atrial natriuretic peptide (MR-proANP) is a strong prognostic marker in several inflammatory, respiratory and cardiovascular conditions, but has not been studied in COVID-19 yet.

METHODS

This prospective, observational study of patients with COVID-19 infection was conducted from 6 June to 26 November 2020 in different wards of a tertiary hospital. MR-proANP, N-terminal pro-brain natriuretic peptide (NT-proBNP) and high-sensitive cardiac troponin I levels on admission were collected and tested for their association with disease severity and 28-day mortality.

RESULTS

A total of 213 eligible patients with COVID-19 were included in the final analyses of whom 13.2% (n = 28) died within 28 days. Median levels of MR-proANP at admission were significantly higher in nonsurvivors (307 pmol/L IQR, [161 - 532] vs 75 pmol/L [IQR, 43 - 153], P < .001) compared to survivors and increased with disease severity and level of hypoxaemia. The area under the ROC curve for MR-proANP predicting 28-day mortality was 0.832 (95% CI 0.753 - 0.912, P < .001). An optimal cut-off point of 160 pmol/L yielded a sensitivity of 82.1% and a specificity of 76.2%. MR-proANP was a significant predictor of 28-day mortality independent of clinical confounders, comorbidities and established prognostic markers of COVID-19 (HR 2.77, 95% CI 1.21 - 6.37; P = .016), while NT-proBNP failed to independently predict 28-day mortality and had a numerically lower AUC compared to MR-proANP.

CONCLUSION

Higher levels of MR-proANP at admission are associated with disease severity of COVID-19 and act as a powerful and independent prognostic marker of 28-day mortality.

Red Cell Distribution Width Upon Hospital Admission Predicts Short-Term Mortality in Hospitalized Patients With COVID-19: A Single-Center Experience

Background: Coronavirus disease (COVID-19) was first described at the end of 2019 in China and has since spread across the globe. Red cell distribution width (RDW) is a potent prognostic marker in several medical conditions and has recently been suggested to be of prognostic value in COVID-19.

Methods: This retrospective, observational study of consecutive patients with COVID-19 was conducted from March 12, 2020 to December 4, 2020 in the Wilhelminenhospital, Vienna, Austria. RDWlevels on admission were collected and tested for their predictive value of 28-day mortality.

Results: A total of 423 eligible patients with COVID-19 were included in the final analyses and 15.4% died within 28 days (n = 65). Median levels of RDWwere significantly higher in non-survivors compared to survivors [14.6% (IQR, 13.7–16.3) vs. 13.4% (IQR, 12.7– 14.4), P < 0.001]. Increased RDW was a significant predictor of 28-day mortality [crude odds ratio (OR) 1.717, 95% confidence interval (CI) 1.462–2.017; P = < 0.001], independent of clinical confounders, comorbidities and established prognostic markers of COVID-19 (adjusted OR of the final model 1.368, 95% CI 1.126–1.662; P = 0.002). This association remained consistent upon sub-group analysis. Our study data also demonstrate that RDW levels upon admission for COVID-19 were similar to previously recorded, non-COVID-19 associated RDW levels [14.2% (IQR, 13.3–15.7) vs. 14.0% [IQR, 13.2–15.1]; P = 0.187].

Conclusions: In this population, RDWwas a significant, independent prognostic marker of short-term mortality in patients with COVID-19.

Immature cell fractions after cessation of chronic P2Y12-inhibition in patients with coronary artery diseases

Changes in circulating cell populations may promote ischemic events that occur soon after discontinuation of P2Y₁₂-inhibition. The aim of the study was to track the course of thrombopoietic and erythropoietic cells in patients with coronary artery diseases (CAD) after planned and physician-driven cessation of chronic P2Y₁₂-inhibition (clopidogrel 75 mg OD, or prasugrel 10 mg OD, or ticagrelor 90 mg BID). Cell fractions were determined in 62 patients at baseline (the last day of P2Y₁₂-inhibitor intake), on day-10, day-30, and day-180 thereafter. Immature platelet fraction (IPF), immature reticulocyte fraction (IRF), reticulocyte hemoglobin content (Ret-Hb) and red blood cell count (RBC) significantly increased from baseline to day-180 (IPF: p = .003; IRF: p = .013; Ret-Hb: p < .001; RBC: p = .044). Platelet count, leucocyte count and immature granulocyte fraction did not change over time (p = .561, p = .869, and p = .161, respectively). Fibrinogen levels significantly declined over time (p = .011), thrombopoietin levels increased in a non-significant manner (p = .379). We did not observe any significant interaction with choice of P2Y₁₂-inhibitor, therefore suggesting a drug class-effect. Our data shows, that discontinuation of dual antiplatelet therapy is associated with raised thrombopoietic and erythropoietic activity in the bone marrow, without significant upregulation of thrombopoietin. This provides further evidence for a direct stimulation of precursor cells by P2Y_12-inhibitors.

Non-bacterial thrombotic endocarditis in the context of pulmonary adenocarcinoma: a case report

Background

Non-bacterial thrombotic endocarditis (NBTE) is a rare condition, usually observed in association with malignancy, lupus erythematosus, or antiphospholipid syndrome. Diagnosis of NBTE remains a challenge as patients are often asymptomatic up to their first thromboembolic event. While there is no randomized data available for the guidance of treatment in NBTE, effective anticoagulation remains the main focus in the management of affected patients.

Case summary

A 44-year-old female patient without a significant medical history presented to the emergency department with a new numbness of her right hand. Magnetic resonance imaging scans facilitated the diagnosis of supratentorial stroke. Within the next 3 months, the patient had multiple thromboembolic events, including multiple strokes, pulmonary embolism, and renal/splenic infarction. Echocardiographic examination revealed large, transient vegetations of the aortic valve with concomitant aortic regurgitation. In addition, an incidental, pulmonary non-small-cell adenocarcinoma was found during the diagnostic work-up. Infective endocarditis was excluded by several negative blood cultures and missing signs of infection. Hence, the diagnosis of NBTE secondary to malignancy was made.

Discussion

We present a rare case of NBTE in the context of pulmonary adenocarcinoma. The adequate treatment of malignancy and effective anticoagulation are the main treatment options.

Is P2Y12 inhibitor therapy associated with an increased risk of cancer?

Antiplatelet therapy is a mainstay of cardiovascular therapy and is well established in clinical routine. Recently, the potential risk of solid cancers with P2Y12 inhibitor therapy has been an issue of growing interest. The alleged association primarily originated from the findings of an US Food and Drug Administration (FDA) review of the randomized controlled TRITON-TIMI 38 trial and the following results of the DAPT trial. The higher risk of cancer was predominately observed with the newer, more potent P2Y12 inhibitors and in the setting of prolonged dual antiplatelet therapy (DAPT). Current European Society of Cardiology (ESC) Guidelines suggest consideration of prolonged DAPT beyond the recommended duration of 6 months in stable coronary artery disease and 12 months in acute coronary syndrome if ischaemic risk prevails over the risk of bleeding. Several trials, studies and meta-analyses have addressed the potential interplay of cancer and P2Y12 inhibition since then. The effect of P2Y12 inhibition on cancer has been investigated extensively in basic research as well. In this review, we summarize current available evidence of cancer risk with P2Y12 inhibitor therapy and discuss the resulting clinical implications.

Carboplatin pharmacokinetics in patients receiving carboplatin and paclitaxel/docetaxel for advanced lung cancers: impact of age and renal function on area under the curve

PURPOSE

To further define the most appropriate way of choosing the dose of carboplatin.

PATIENTS AND METHODS

The pharmacokinetics of carboplatin were analyzed in 30 patients with advanced lung cancer receiving a total of 48 cycles of carboplatin plus paclitaxel/ docetaxel combination chemotherapy. Platin concentrations of ultrafiltrated plasma and urine samples were determined by flameless atomic absorption spectrometry. A multiple regression analysis was performed for interactions between pharmacokinetic parameters and pretreatment characteristics.

RESULTS

Using a twocompartment-model, the following parameters were obtained (mean, coefficient of variation): initial half-life, 0.903 h (48%); terminal half-life, 13.6 h (116%); maximum plasma concentration (Cmax), 38.5 microM (86%); AUC, 111.9 microM/h (86%); volume of distribution, 411 l (130%); total clearance (Ct), 579 ml/min (75%); renal clearance (Cr), 453 ml/min (80%); renal elimination, 76% of dose (17%). In the univariate analysis, age was significantly related to Cmax (P = 0.0303), AUC (P = 0.0050), Ct (P = 0.0020), Cr (P = 0.0092). Plasma creatinine (Crp) was related to Cmax (P = 0.0228), and 1/[Crp] was related to Cmax (P = 0.0015) and AUC (P = 0.0054), while body weight was related to Cmax (P = 0.0365). No interaction with the schedule of application of the two drugs was observed. In the multivariate analysis, factors significantly related to AUC were 1/[Crp] (P < 0.01) and age (P < 0.01). Crp (P < 0.05) and 1/[Crp] (P < 0.01) were significantly associated with Cmax.

CONCLUSIONS

These data stress the importance of dosing carboplatin according to renal function and age and warrant further analyses to validate this concept prospectively.

Effects of amifostine in a patient with an advanced-stage myelodysplastic syndrome

We report on a 63-year-old man with myelodysplastic syndrome at the stage of a refractory anemia with an excess of blasts in transformation (MDS-RAEB-T), first diagnosed in December 1996. After a period of stability, with no need for transfusions, the MDS progressed into acute myeloid leukemia (AML) in August 1998 with the emergence of a cytogenetic abnormality (11q-). Two courses of chemotherapy were given, resulting in prolonged pancytopenia; however, no clearance of bone marrow (BM) blasts was achieved. At that time, severe infections and daily epistaxis occurred. Frequent transfusions of packed red blood cells (RBC) and platelets (2-3/week) were necessary. After 2 months of persisting severe pancytopenia, we started a therapy with amifostine: 4 x 250 mg intravenously (i.v.) weekly for 1 month, followed by a maintenance therapy with 500 mg once weekly. After 2 weeks of amifostine therapy, hematopoiesis began to improve. In the subsequent 2 months, the patient became completely independent of the platelet transfusions; the transfusion frequency of RBC was permanently reduced (2 RBC transfusions/month) and a significant decrease of BM blasts was achieved. After 30 weeks of amifostine therapy, the morphology of the MDS switched to a chronic myelomonocytic leukemia (CMML)-like appearance, with continuously increasing leukocytes, so that we discontinued amifostine therapy for 1 month to exclude a possible side effect of amifostine. At that time, leukocytes further increased to 74,000/microl; thus, we decided to perform a cytoreductive chemotherapy (hydroxycarbamide) and continued weekly amifostine infusions. During 1 year of amifostine therapy, the patient had a good quality of life, with no need for hospitalization and a complete cytogenetic remission. We conclude that, in this case, amifostine had two effects: a significant improvement of impaired hematopoiesis and a slowing down of disease progression. Thus, amifostine might be a therapeutic option in older patients with advanced MDS.

Microalbuminuria during cisplatin therapy: relation with pharmacokinetics and implications for nephroprotection

BACKGROUND

To assess the relation of cisplatin-induced nephrotoxicity to its pharmacology.

PATIENTS AND METHODS

In 22 chemonaive patients (median age, 32 years) receiving 100-150 mg/m2 cisplatin for a total of 54 courses of therapy pharmacokinetics of ultra-filtrable platin were analyzed. Nephrotoxicity was sensitively assessed by nephelometric analyses of urinary marker-proteins.

RESULTS

The parameters calculated for ultrafiltrable platin were (two-compartment-model): terminal half-life, 36 hours (coefficient of variation [CV], 22%); AUC, 12852 ng h/ml (33%); volume of distribution, 3531 (44%); total clearance, 285 ml/min (30%); renal clearance, 149 ml/min (23%); maximum concentration, 1720 ng/ml (66%); renal elimination, 57% of applied dose (26%). A pathological urinary excretion of albumin > 20 mg/l and alpha-1-microglobulin > 10 mg/l was detected in 39 out of 54 and 42 out of 54 cycles, respectively. The degree of albuminuria was related with urinary monoaquoplatin concentrations (p = 0.003).

CONCLUSION

Nephrotoxicity of cisplatin appears to depend on the urinary monoaquoplatin concentrations which may be modulated by application of saline.

Oxaliplatin pharmacokinetics during a four-hour infusion

A new platin compound, oxaliplatin, has significant activity in advanced colorectal carcinomas. However, its pharmacokinetics have not been characterized adequately yet. This study extensively analyzes the pharmacokinetics of both ultrafiltrable (free) and protein-bound platin in 13 patients receiving 130 mg/m2 oxaliplatin as a 4-h infusion in combination with 375 mg/m2 5-fluorouracil as a 24-h infusion for advanced colorectal carcinomas. The interpatient variability was very low for all parameters analyzed. The levels of free platin decreased triphasically, with a mean terminal half-life of 27.3+/-10.6 h. The area under the time-concentration curve was 20.17+/-6.97 microg.h/ml and the total and renal clearances amounted to 222+/-65 and 121+/-56 ml/min, respectively. The values for the volume of distribution and for the maximum concentration at the end of infusion were 349+/-132 liters and 1612+/-553 ng/ml, respectively. On the basis of the simulation of the plasma levels and the urinary excretion of platin following the long-term administration of oxaliplatin as a constant-rate and a chronomodulated infusion, additional analyses are warranted to fully characterize the pharmacokinetics of the drug in these settings.

Oral idarubicin pharmacokinetics--correlation of trough level with idarubicin area under curve

Idarubicin is the first anthracycline that can be successfully administered via the oral route and thus may facilitate antineoplastic chemotherapy in an improved quality of life. These perspectives are somewhat hampered by the large variation in bioavailability between individual patients and the obvious requirement to monitor plasma concentration and area-under-the-curve values (AUC) for an appropriate adjustment of idarubicin dose. In this study we describe the pharmacokinetics of idarubicin and its main metabolite idarubicinol in 12 patients after oral application of 20 mg/m2 idarubicin on 3 consecutive days and demonstrate that the 24 h trough levels show a high correlation with AUC and may thus allow a rapid and easy determination of individual drug concentrations and an appropriate dose adjustment. The average terminal half-life was 30.5 h for idarubicin and 66.9 h for idarubicinol. The AUC for idarubicin and its main metabolite idarubicinol revealed a substantial interpatient variation with AUC values ranging from 25.7 to 114 ng x h/ml (average 58.1 ng x h/ml) for idarubicin and from 109.4-445.2 ng x h/ml (average 287.3 ng x h/ml) for idarubicinol. However, the ratio of idarubicin/idarubicinol differed only two folds from 1:3.7 to 1:7.7 with an average of 1:5.1. Both idarubicin and idarubicinol concentrations were highly reproducible, however, upon measurements after repeated applications within individual patients. Moreover, idarubicinol and idarubicin AUCs showed a good correlation with r = 0.78, indicating that the interindividual variation of idarubicin AUC reflects differences in absorption rather than in metabolism. In order to describe the interindividual bioavailability of idarubicin - represented by the respective AUC - measurement of a single data point with a high correlation with the AUC would be ideal. Our study demonstrates that the 24 h trough level shows such an excellent correlation (r = 0.96) with AUC, making it the perfect candidate for fast estimates of the individual bioavailability in a given patient. On this basis, the longitudinal measurement of the 24 h trough level may allow assessment of the impact of interindividual variations in AUC on clinical outcome and toxicity.

[Brief interdisciplinary oncology: a model for ambulatory, multimodal treatment of tumor patients]

Since 10/1994 the Interdisziplinäre Kurzzeit-Onkologie (IKO) is an outpatient department for the treatment of patients with cancer used by the departments of hematology/oncology and surgery. Between 09/1995 and 02/1997, 818 patients received 2024 cytotoxic therapies with neoadjuvant (15%), adjuvant (65%) or palliative (20%) intention-mostly within multicenter clinical studies. Ambulatory operations like removal of lymph nodes for diagnosis or the implantation of venous catheter systems prepared the way for specialized modalities of cancer therapy. The high compliance and consent of patients, combined with better understanding of cancer therapy, resulted in an enhanced quality of life and optimized therapy. Standardization in diagnostics and fast realisation of interdisciplinary treatment schedules lead to reduction of costs and to enhancement of quality and security in cancer therapy.

Response to cytarabine ocfosfate (YNK01) in a patient with chronic lymphocytic leukemia refractory to treatment with chlorambucil/prednisone, fludarabine, and prednimustine/mitoxantrone

Cytarabine ocfosfate (YNK01) is a novel orally applicable prodrug of cytosine arabinoside. Recent pharmacokinetic studies have revealed a prolonged release of the cytotoxic agent cytosine arabinoside (araC) from hepatocytes into the systemic circulation, resulting in a half-life of approximately 24 h for araC. The specific pharmacokinetic characteristics of cytarabine ocfosfate lead to a prolonged exposure of leukemic cells to this antineoplasstic agent during the 14-day cycle. the oral applicability during outpatient treatment and the sustained antineoplastic activity of araC against slowly proliferating leukemic B-cells suggest that cytarabine ocfosfate might be a useful drug in the treatment of chronic lymphocytic leukemia. Four years after diagnosis of B-CLL, a 50-year-old patient was started on cytarabine ocfosfate. Sequentially, the patient's disease had proved refractory to treatment with chlorambucil/prednisone (31 months), fludarabine (5 months), and prednimustine/mitoxantrone (3 months). These established regimens were discontinued because of increasing lymphocytosis, significant thrombocytopenia, and progressive B-symptoms. Following three cycles of cytarabine ocfosfate B-symptoms resolved, lymphadenopathy disappeared, and thrombocytopenia was significantly reduced. The patient has been free of these symptoms on a dosage of 1500 mg cytarabine ocfosfate/day (cycle of 14 days with intervals of 14-21 days) for 24 months and remains in an ongoing partial remission.

Oral idarubicin pharmacokinetics--correlation of trough level with idarubicin area under curve

Idarubicin is the first anthracycline that can be successfully administered via the oral route and thus may facilitate antineoplastic chemotherapy at an improved quality of life. These perspectives are somewhat hampered by the large variation in bioavailability between individual patients and the obvious requirement to monitor plasma concentration and area-under the curve values (AUC) for an appropriate adjustment of idarubicin dose. In this study we describe the pharmacokinetics of idarubicin and its main metabolite idarubicin in 12 patients after oral application of 20 mg/m2 idarubicin on 3 consecutive days and demonstrate that the 24-h trough levels shows high correlation with AUC and may thus allow a rapid and easy determination of individual drug concentrations and an appropriate dose adjustment. The average terminal half-life was 30.5h for idarubicin and 66.9 h for idarubicinol. The AUC for idarubicin and its main metabolite idarubicinol revealed a substantial interpatient variation with AUC values ranging from 25.7 to 114 ng x h/ml (average 58.1 ng x h/ml) for idarubicin and from 109.4 - 445.2 ng x h/ml (average 287.3 ng x h/ml) for idarubicinol. However, the ratio of idarubicin/idarubicinol differed only two-fold from 1:3.7 to 1:7.7 with an average of 1:5.1. Both idarubicin and idarubicinol concentrations were highly reproducible, however, upon measurements after repeated applications within individual patients. Moreover, idarubicinol and idarubicin AUCs showed a good correlation with r=0.78, indicating that the interindividual variations of idarubicin AUC reflects differences in absorptions rather than metabolism. In order to describe the interindividual bioavailability of idarubicin - represented by AUC - measurement of a single data point with a high correlation with the AUC would be ideal. Our study demonstrates that the 24-h trough level shows such an excellent correlation (r=0.96) with AUC, making it the perfect candidate for fast estimates of the individual bioavailability in a given patient. On this basis, the longitudinal measurement of the 24-h trough level may allow the assessment of the impact of interindividual variations in AUC of clinical outcome and toxicity.

Detection and determination of the major metabolites of [3H]cytosine arabinoside by high-performance liquid chromatography

An ion-pair high-performance liquid chromatographic assay involving solid-phase scintillation detection was established for the rapid identification and determination of all major metabolites of tritium-labelled cytosine arabinoside (Ara-C) in an in vitro system. In a single run of 50 min, Ara-C, Ara-CMP, Ara-CDP-choline, Ara-CDP, Ara-U, Ara-UMP, Ara-CTP, Ara-UDP and Ara-UTP can be measured. The method is fast, sensitive, with limits of detection ranging from 40 to 200 pg (absolute), and highly reproducible.

Highly sensitive high-performance liquid chromatographic assay for 1-beta-D-arabinofuranosylcytosine-5'-stearyl phosphate (cytarabine-ocfosfate)

An ion-pair HPLC method for the determination of 1-beta-D-arabinofuranosylcytosine-5'-stearyl phosphate (cytarabine-ocfosfate I) was developed, using a phenyl-bonded column under reversed-phase conditions with a mobile phase of acetonitrile-buffered water (pH 6.8) (50:50) for isocratic elution. A reproducible sample clean-up was achieved by solid-phase extraction. In order to reach the low limit of detection of 2 ng/ml, an enrichment switching system was used. The present validation leads to a limit of quantification of 5 ng/ml with a coefficient of variation (C.V.) of 10%. The total time of measurement was shortened by a back-flush procedure to restore the conditions after each run. UV detection at 275 nm was applied. The recoveries for plasma samples ranged from 56.4 to 64.1%, regardless of drug concentrations. The intra-assay C.V. was about 4% (40 measurements at four different concentrations). The inter-assay recovery (ten measurements over ten days) at a plasma concentration of 50 ng/ml was 57% with a C.V. of 8.25%. Based on this HPLC method, the pharmacokinetics of I were measured during a clinical phase I/II study.

Albuminuria in HIV-infected patients

Albumin excretion, Analysis of urinary proteins by polyacrylamide gel electrophoresis (PAGE), and clinical evaluation were performed in 90 HIV-infected patients to assess subclinical renal involvement in HIV infection. Thirteen percent of all patients showed an albumin excretion > 20 mg/liter. Seven of four homosexual patients had albuminuria. Albuminuria occurred exclusively with T4 cell counts below 200/mm3. Polyacrylamide gel electrophoresis indicated glomerular lesions and showed no tubular proteinuria in patients with increased albumin excretion. It is concluded that subclinical renal involvement is not uncommon in HIV infection with T4 cell counts > 200/mm3. HIV-associated nephropathy and heroin-associated nephropathy may not be the main causes of renal involvement. In some cases, opportunistic viral infections may be the cause of microalbuminuria.

New aspects on the pharmacokinetics of mitoxantrone and its two major metabolites

In spite of its broad clinical application in the treatment of malignant disorders, the pharmacokinetics of mitoxantrone are still not fully understood and warrant further investigation. Information is also limited about interindividual differences in the plasma AUC infinity (area-under-the-curve concentration to time infinity) and renal elimination of mitoxantrone and its main metabolites, mono- and dicarboxylic acid. In the present study, the plasma concentration of mitoxantrone was measured by HPLC during 120 h after the end of a 30-min infusion of 10 mg/m2 in 18 patients undergoing combination therapy with mitoxantrone and high-dose cytosine arabinoside for acute myeloid leukemia. Plasma kinetics and renal elimination of mono- and dicarboxylic acid were analyzed in addition in eight of these patients, and in five cases with chronic lymphocytic leukemia receiving a 30-min infusion of 5 mg/m2 mitoxantrone weekly for 3 consecutive weeks. Fitting the results to a three compartment model, a substantial interindividual variation was observed for plasma and urine pharmacokinetics. Plasma AUC infinity for mitoxantrone differed approximately 13-fold between individual patients and varied between 80-1030 ngh/ml. The corresponding values for mono- and dicarboxylic acid ranged from 23-147 ngh/ml and 51-471 ngh/ml, respectively. The median terminal half-life for mitoxantrone was similar to that of the mono- and dicarboxylic acid and was 75 h. Cumulative renal elimination ranged from 670-1950 micrograms for mitoxantrone, from 366-852 micrograms for monocarboxylic acid, and from 792-3420 micrograms for dicarboxylic acid. Renal clearance of mitoxantrone reached a median level of 69 ml/min and for the total plasma clearance a median of 1136 ml/min was found. The corresponding values for the mono- and dicarboxymetabolites were 57 and 67 ml/min. In contrast to the great interindividual differences in pharmacokinetic results, a low intraindividual variability was observed upon repeated determinations of renal elimination of mitoxantrone and its metabolites at weekly intervals in five patients. These data provide new insights into the pharmacokinetic of mitoxantrone and its main metabolites revealing substantial differences in drug metabolism and elimination between individual patients. Further studies are needed to explore the potential impact on response and/or toxicity and the requirement of a pharmacokinetic directed adjustment of drug dosage in clinical trials.

Column-switching solid-phase trace-enrichment high-performance liquid chromatographic method for measurement of buprenorphine and norbuprenorphine in human plasma and urine by electrochemical detection

We describe a new high-performance liquid chromatographic method using electrochemical detection for the determination of buprenorphine and norbuprenorphine in plasma and urine. The minimum concentration for detection of buprenorphine and norbuprenorphine is 40 pg/ml. The intra-assay coefficient of variation (C.V.) in plasma and urine samples ranges from 6 to 17% depending on the drug concentration. At a plasma concentration of 500 pg/ml the inter-assay C.V. is 8% for buprenorphine and 9% for norbuprenorphine. The analysis duration is 16 min. After solid-phase extraction and evaporation a valve-switching system with two Rheodyne valves enables sample enrichment, optimal sample cleaning and rapid elution of long-retained substances.