Pericardial fluid troponin in cardiac surgery.

BACKGROUND AND OBJECTIVE: Pericardial Fluid (PF) is a rich reservoir of biologically active factors. Due to its proximity to the heart, the biochemical structure of PF may reflect the pathological changes in the cardiac interstitial environment. This manuscript aimed to determine whether the PF level of cardiac troponins changes in patients undergoing cardiac surgery. METHODS: This scoping review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Medline, EMBASE, Cochrane, ClinicalTrials.gov, and Google Scholar databases were electronically searched for primary studies using the keywords "pericardial fluid," "troponin," and "cardiac surgery." The primary outcome of interest was changes in troponin levels within the PF preoperatively and postoperatively. Secondary outcomes of interest included comparisons between troponin level changes in the PF compared to plasma. RESULTS: A total of 2901 manuscripts were screened through a title and abstract stage by two independent blinded reviewers. Of those, 2894 studies were excluded, and the remaining seven studies underwent a full-text review. Studies were excluded if they did not provide data or failed to meet inclusion criteria. Ultimately, six articles were included that discussed cardiac troponin levels within the PF in patients who had undergone cardiac surgery. Pericardial troponin concentration increased over time after surgery, and levels were significantly higher in PF compared to serum. All studies found that the type of operation did not affect these overall observations. CONCLUSION: Our review of the literature suggest that the PF level of cardiac troponins increases in patients undergoing cardiac surgery, irrespective of the procedure type. However, these changes' exact pattern and clinical significance remain undefined.

Pericardial Cytokine "Storm" in a COVID-19 Patient: the Confirmation of a Hypothesis.

Novel Coronavirus Disease in most cases produces mild symptoms which resolve after a few days. Some authors hypothesized that SARS-CoV-2 infection could trigger excessive cytokine production leading to a severe multi-organ disease requiring intensive care admission. Respiratory and neurological symptoms are the most frequently reported manifestation of the disease. Indeed, cardiac involvement is reported mostly as a part of a systemic disease. Few isolated cardiac manifestations of COVID-19 infection have been described. We report herein a case of SARS-CoV-2 related severe isolated pericardial involvement requiring ICU admission due to cardiac tamponade needing urgent drainage. Analysis of pericardial fluid from drainage demonstrated a higher cytokine concentration than blood values. Other causes of pericardial disease, such as autoimmunity, bacterial or other than COVID-19 infection, neoplasms or acute myocardial infarction were also evaluated, but all tests confirmed negative results. The suspicion of isolated involvement of the pericardium was therefore demonstrated by the analysis of cytokines which strongly support our hypothesis.

Diagnostic value of high-sensitivity troponin T in postmortem diagnosis of sudden cardiac death.

INTRODUCTION: Ischemic heart disease is the most common cause of sudden cardiac death. By autopsy, there may be no histologic evidence of acute myocardial damage few hours after death. The use of cardiac troponins in the postmortem diagnosis of sudden cardiac death is well known in the forensic setting. However, high-sensitivity cardiac troponin T (Hs-TnT) assay in cadaver fluids was tested in few studies. The aim of this study is to assess the diagnostic value of postmortem dosage of Hs-TnT in the diagnosis of sudden cardiac death. MATERIAL AND METHODS: Our study is prospective, dealing with cadavers autopsied at the Department of Forensic Medicine of the University Hospital Habib Bourguiba of Sfax-Tunisia from December 2016 to April 2018. Were excluded from the study resuscitated cases, severely traumatized victims and cadavers that were examined more than 36 h after death. Levels of Hs-TnT were measured in pericardial fluid, cardiac blood and peripheral blood. RESULTS: A total of 80 cases were identified with an average age of 44.5 ± 19 years. Hs-TnT levels in pericardial fluid and heart blood were correlated significantly between cardiac and non-cardiac groups with a p-value respectively at 0.14 and 0.04. Receiver-operator characteristic curves analysis showed that the pericardial fluid had the best sensibility (75%) and specificity (64%) with a cut-off level at 17.72 ng/ml and an area under the curve at 0.747. We found also a significant correlation between postmortem interval and Hs-TnT levels in pericardial fluid, cardiac and peripheral blood. CONCLUSION: Our data indicate that determination of cardiac troponin T by a highly sensitive assay in pericardial fluid may be a powerful aid in the postmortem diagnosis of sudden cardiac death.

What is the normal composition of pericardial fluid?

OBJECTIVE: Biochemical and cytological pericardial fluid (PF) analysis is essentially based on the knowledge of pleural fluid composition. The aim of the present study is to identify reference intervals (RIs) for PF according to state-of-art methodological standards. METHODS: We prospectively collected and analysed the PF and venous blood of consecutive subjects undergoing elective open-heart surgery from July 2017 to October 2018. Exclusion criteria for study enrolment were evidence of pericardial diseases at preoperatory workup or at intraoperatory assessment, or any other condition that could affect PF analysis. RESULTS: The final study sample included 120 patients (median age 69 years, 83 men, 69.1%). The main findings were (1) High levels of proteins, albumin and lactate dehydrogenase (LDH), but not of glucose and cholesterol (2) High cellularity, mainly represented by mesothelial cells. RIs for pericardial biochemistry were: protein content 1.7-4.6 g/dL PF/serum protein ratio 0.29-0.83, albumin 1.19-3.06 g/dL, pericardium-to-serum albumin gradient 0.18-2.37 g/dL, LDH 141-2613 U/L, PF/serum LDH ratio 0.40-2.99, glucose 80-134 mg/dL, total cholesterol 12-69 mg/dL, PF/serum cholesterol ratio 0.07-0.51. RIs for pericardial cells by optic microscopy were: 278-5608 × 106 nucleated cells/L, 40-3790 × 106 mesothelial cells/L, 35-2210 × 106 leucocytes/L, 19-1634 × 106 lymphocytes/L. CONCLUSIONS: PF is rich in nucleated cells, protein, albumin, LDH, at levels consistent with inflammatory exudates in other biological fluids. Physicians should stop to interpret PF as exudate or transudate according to tools not validated for this setting.

Diagnostic values of Xpert MTB/RIF, T-SPOT.TB and adenosine deaminase for HIV-negative tuberculous pericarditis in a high burden setting: a prospective observational study.

The diagnosis of tuberculous pericarditis (TBP) remains challenging. This prospective study evaluated the diagnostic value of Xpert MTB/RIF (Xpert) and T-SPOT.TB and adenosine deaminase (ADA) for TBP in a high burden setting. A total of 123 HIV-negative patients with suspected TBP were enrolled at a tertiary referral hospital in China. Pericardial fluids were collected and subjected to the three rapid tests, and the results were compared with the final confirmed diagnosis. Of 105 patients in the final analysis, 39 (37.1%) were microbiologically, histopathologically or clinically diagnosed with TBP. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio (DOR) for Xpert were 66.7%, 98.5%, 96.3%, 83.3%, 44.0, 0.338, and 130.0, respectively, compared to 92.3%, 87.9%, 81.8%, 95.1%, 7.6, 0.088, and 87.0, respectively, for T-SPOT.TB, and 82.1%, 92.4%, 86.5%, 89.7%, 10.8, 0.194, and 55.8, respectively, for ADA (≥ 40 U/L). ROC curve analysis revealed a cut-off point of 48.5 spot-forming cells per million pericardial effusion mononuclear cells for T-SPOT.TB, which had a DOR value of 183.8, while a cut-off point of 41.5 U/L for ADA had a DOR value of 70.9. Xpert (Step 1: rule-in) followed by T-SPOT.TB [cut-off point] (Step 2: rule-out) showed the highest DOR value of 252.0, with only 5.7% (6/105) of patients misdiagnosed. The two-step algorithm consisting of Xpert and T-SPOT.TB could offer rapid and accurate diagnosis of TBP.

Postmortem distribution/redistribution of buformin in body fluids and solid tissues in an autopsy case using liquid chromatography-tandem mass spectrometry with QuEChERS extraction method.

An autopsy for a suicidal case of a male in his 40s, who had died of poisoning due to ingestion of a large amount of buformin, was performed at our department. Buformin is biganide class agent used for patients of diabetes mellitus, which can occasionally cause severe lactic acidosis. The autopsy was performed about 10 days after his death, and the direct cause of his death was judged as asphyxia due to the aspiration of stomach contents into the airway. The nine body fluids and eight solid tissues specimens were dealt with for investigating postmortem distribution/redistribution of buformin in a whole body; femoral vein blood, right and left heart blood, pericardial fluid, urine, bile, stomach contents, small intestine contents, cerebrospinal fluid, the brain, lung, heart muscle, liver, spleen, kidney and skeletal muscle were examined. For extracting buformin from specimens, a modified QuEChERS method including dispersive solid-phase extraction was employed, followed by the analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS). Buformin in various kinds of human matrices were quantified by the standard addition method in this study, which can overcome the matrix effects and recovery rates without use of blank human matrices. All concentrations of buformin in specimens examined in this case were extremely higher than those of previously reported poisoning cases. The concentrations of buformin in left and right heart blood and femoral vein blood specimens of this case were 399, 216 and 261µg/mL, respectively; although the direct cause of his death was judged as asphyxia due to occlusion of airway with stomach contents, the vomiting was thought to be provoked by buformin poisoning. In this study, marked differences of buformin concentrations between brain tissue and cerebral spiral fluids, and other specimens were observed, which suggested that its distribution was influenced also by blood-brain-barrier. Although a number of buformin poisoning cases were published so far, they gave sporadic data on its concentrations and/or distribution in some limited human specimens. This study is the first to describe detailed distribution/redistribution of buformin in a whole human body quantified by using LC-MS/MS.

Contemporary biochemical analysis of normal pericardial fluid.

OBJECTIVE: Biochemical analysis of pericardial fluid (PF) is commonly performed for the initial assessment of PF, and the results are usually interpreted according to Light's traditional criteria for the differential diagnosis of transudates versus exudates. However, Light's criteria have been formulated for the biochemical analysis of pleural fluid. The aim of the present paper is to evaluate the normal composition of PF in candidates for cardiac surgery. METHODS: Cohort study with analysis of PF from candidates for cardiac surgery. Exclusion criteria were previous pericardial disease or cardiac surgery, prior myocardial infarction within 3 months, systemic disease (eg, systemic inflammatory diseases, uremia) or drug with potentiality to affect the pericardium. RESULTS: Fifty patients (mean age was 67 years; 95% CI 64 to 71, 29 males, 58.0%) were included in the present analysis. Levels of small molecules were similar in blood and PF. Total proteins in PF was, on average, 0.5 times lower than corresponding plasma levels (p=0.041), while the level of pericardial lactate dehydrogenase was, on average, 1.06 times higher than plasma (p=0.55). Moreover, mononuclear cells were more concentrated in PF than plasma (p=0.17). Traditional Light's criteria misclassified all PFs as exudates. CONCLUSIONS: Traditional Light's criteria misclassified normal PFs in candidates for cardiac surgery as exudates. This study suggests their futility for the biochemical analysis of PF in clinical practice.

Quantitative analysis of aconitine in body fluids in a case of aconitine poisoning.

Aconitine belongs to the Aconitum alkaloids and is a natural toxic substance. Aconitine has been used as a traditional medicine in East Asian culture. Today, aconitine is still in use with or without a prescription, in the Republic of Korea. Here we present a case report of accidental death due to acute aconitine poisoning. An 81-year-old woman ingested liquid that had been heat extracted from the root of the Aconitum plant; she presented to the emergency room 1 h after ingestion. Her electrocardiogram showed irregular ventricular arrhythmias including ventricular tachycardia; she progressed to cardiac arrest. Cardiopulmonary resuscitation and anti-arrhythmic drugs were administered, but the patient did not survive. An autopsy was performed 2 days postmortem. Toxicological analysis was performed, and aconitine was detected by liquid chromatography tandem mass spectrometry. The antemortem blood concentration of aconitine was 39.1 ng/ml and the concentrations of aconitine in the postmortem cardiac blood, peripheral blood, cerebrospinal fluid (CSF), pericardial fluid, and urine were 21.1 ng/ml, 28.6 ng/ml, 6.8 ng/ml, 24.1 ng/ml, and 67.4 ng/ml, respectively. This is the first forensic case report of an aconitine poisoning death in the Republic of Korea with quantitative measurement of aconitine in the antemortem blood and various postmortem body fluids. To the best of our knowledge, this is the first report of the detection of aconitine in the CSF. These data about the distribution of aconitine in the antemortem blood and various postmortem body fluids is helpful for future aconitine poisoning death cases.

Biochemical findings in sudden unexpected death in epilepsy: Hospital based case-control study.

PURPOSE: A review study on the biochemistry of epilepsy showed that in epileptic patients, serum glucose and cholesterol concentrations are low, sodium is unaffected, potassium increases, glucose is high and mild hypocalcemia. We have conducted a biochemical study on sudden unexpected death in epilepsy (SUDEP) cases in an attempt to establish the characteristic biochemical values to diagnose these deaths. METHODS: This was a hospital based case-control study done at All India Institute of Medical Sciences, New Delhi for one year. Twenty SUDEP cases and 20 age- and sex-matched controls were included in the study. Femoral blood, cerebrospinal fluid, vitreous humor, and pericardial fluid were biochemically analyzed for sodium, potassium, calcium, glucose, N-acetyl- cysteine activated creatine kinase (CK-NAC) and isoenzyme CK-MB. RESULT: Serum sodium, CK-MB and CK-NAC level was found significantly increased and potassium level was found decreased in SUDEP cases in comparison to non-epileptic deaths. Likewise, in CSF, sodium and CK-NAC was found increased and potassium level was found decreased in SUDEP cases. In vitreous humor, sodium and CK-MB level was found increased and potassium level was found decreased in SUDEP cases in comparison to non-epileptic deaths. In pericardial fluid, sodium, CK-NAC and CK-MB level was found increased and potassium level was found decreased in SUDEP cases in comparison to non-epileptic deaths. CONCLUSION: It concludes that high sodium level and low potassium level could be associated with SUDEP. However, this is a small size study, a larger study is needed to verify the findings. Furthermore, it is difficult to conclude whether these findings are exclusive to SUDEP.

Organ distribution of diclazepam, pyrazolam and 3-fluorophenmetrazine.

The organ distribution of 3-fluorophenmetrazine (3-FPM), pyrazolam, diclazepam as well as its main metabolites delorazepam, lormetazepam and lorazepam, was investigated. A solid phase extraction (SPE) and a QuEChERS (acronym for quick, easy, cheap, effective, rugged and safe) - approach were used for the extraction of the analytes from human tissues, body fluids and stomach contents. The detection was performed on a liquid chromatography-tandem mass spectrometry system (LCMS/MS). The analytes of interest were detected in all body fluids and tissues. Results showed femoral blood concentrations of 10 µg/L for 3-FPM, 28 µg/L for pyrazolam, 1 µg/L for diclazepam, 100 µg/L for delorazepam, 6 µg/L for lormetazepam, and 22 µg/L for lorazepam. Tissues (muscle, kidney and liver) and bile exhibited higher concentrations of the mentioned analytes than in blood. Additional positive findings in femoral blood were for 2-fluoroamphetamine (2-FA, approx. 89 µg/L), 2-flourometamphetamine (2-FMA, hint), methiopropamine (approx. 2.2 µg/L), amphetamine (approx. 21 µg/L) and caffeine (positive). Delorazepam showed the highest ratio of heart (C) and femoral blood (P) concentration (C/P ratio = 2.5), supported by the concentrations detected in psoas muscle (430 µg/kg) and stomach content (approx. 210 µg/L, absolute 84 µg). The C/P ratio indicates that delorazepam displays susceptibility for post-mortem redistribution (PMR), supported by the findings in muscle tissue. 3-FPM, pyrazolam, diclazepam, lorazepam and lormetazepam did apparently not exhibit any PMR. The cause of death, in conjunction with autopsy findings was concluded as a positional asphyxia promoted by poly-drug intoxication by arising from designer benzodiazepines and the presence of synthetic stimulants.

Characterization of lymphocyte subpopulations and cardiovascular markers in pericardial fluid of cardiac surgery patients.

BACKGROUND: Composition of pericardial fluid (PF) may reveal immunological processes influencing oxidative stress and microcirculation of different tissues of the heart and may play a role in the course of myocardial infarction, atherosclerosis, and aortic stenosis. PATIENTS AND METHODS: We investigated lymphocyte populations, cardiovascular markers and immunoglobulin composition in PF and blood samples of patients undergoing CABG operation and compared them to those who had aortic valve surgery. RESULTS: The amount of CD8 + T, NK, memoT and activated T-cytotoxic cells were elevated in PF compared to blood, but naiveT and activated T-helper cell ratio were lower in PF. Amount of activated T-helper cells and regulatory T-lymphocytes were elevated in CABG participants in both PF and blood. INKT cells represented the only regulatory lymphocyte population reaching significantly higher concentration in PF than in blood. IL-6 and MCP1 level were elevated in PF compared to blood and MCP1 plasma level was markedly elevated in CABG group. CONCLUSIONS: Our study describes a comprehensive immunological analysis of PF in humans for the first time. We showed that the investigated lymphocyte populations and cardiovascular markers in PF have significantly different distribution compared to blood, and lymphocyte populations show different compartmentization in coronary disease and aortic stenosis.

Biochemical investigations performed in pericardial fluid in forensic cases that underwent postmortem angiography.

Postmortem biochemical investigations in vitreous humor samples collected before and after performing multiphase postmortem computed tomography angiography were performed in the past and demonstrated that specific contrast material injection allowed perfusion and radiological identification of the main vessels of the eye to be obtained without any changes in vitreous humor composition. In the study presented herein, we aimed to test whether the injection of the same contrast material using the same postmortem angiography protocol might influence pericardial fluid composition. Postmortem biochemical investigations were performed on pericardial fluid samples collected from bodies that underwent postmortem angiography (n = 16) prior to and post angiography. Two pericardial fluid samples were analyzed. No statistically significant differences were noticed among levels of any tested markers (urea nitrogen, creatinine, uric acid, C-reactive protein, procalcitonin, beta-hydroxybutyrate, and total IgE levels) in pericardial fluid samples collected prior to and post angiography, leading to the conclusion that pericardial fluid sampling can be delayed until after postmortem angiography when a specific contrast material injection is used.

The use of cardiac troponin T (cTnT) in the postmortem diagnosis of acute myocardial infarction and sudden cardiac death: A systematic review.

Being sudden cardiac death (SCD) and acute myocardial infarction (AMI) frequent occurrences in forensic medicine, extensive research has been published about the use of cardiac troponin T (cTnT) as a potential specific postmortem biochemical marker. However, cTnT has produced uncertain results, leading to the lack of a standardized application in routine postmortem examinations. The present systematic review focuses on the determination of whether cTnT may be considered as a suitable marker for the postmortem diagnosis of AMI and SCD, analysing the literature according to the following criteria: only human experiments, published from 1st January 2001 to 12th April 2018, available in English, on the following databases: (1). Medline/PubMed/MeSH search words: (("heart"[MeSH Terms] OR "cardiac"[All Fields]) AND ("troponin"[MeSH Terms] OR "troponins"[All Fields]) AND forensic[All Fields] AND "postmortem"[All Fields]); (2). Embase, Lilacs and Cochrane Library. 16 full-text articles were included. cTnT has been demonstrated to be elevated in a variety of pathological conditions, not strictly related to cardiac causes, but rather to the severity and extent of myocardial damage from various causes. cTnT levels have been consistently found higher in pericardial fluid than in the peripheral blood. Reviewed studies showed that the most suitable biological sample for cTnT evaluation seems to be pericardial fluid, since it may be less affected by haemolysis of blood. cTnT seems to be quite stable up to a PMI (postmortem interval) smaller than 48h; after this time, a mild time-dependent increase has been demonstrated. CPR seems to have no influence on cTnT values. The postmortem cut-offs differ from clinical ones, and at present no consensus has been reached concerning the postmortem ranges. Further research needs to be carried out in order to establish a common accepted cut-off value for forensic use.

Determination of benzodiazepines in pericardial fluid by gas chromatography-mass spectrometry.

In Forensic Toxicology it is sometimes impossible to obtain a valid blood sample to perform toxicological analysis due to several factors like advanced state of decomposition, severe burns, bleed to death…. Pericardial Fluid has already been studied during the last years and has been proposed as a valid specimen for toxicological tests. Over the years, the consumption of benzodiazepines spread among the drug dependent population and became noticeable in drug facilitated assault cases and road accidents. Improvement of the analytical methodology required for detecting the presence of these drugs in biological samples is of great importance for forensic toxicology, in order to correctly diagnose an exposure or a poisoning. In this study, 9 benzodiazepines (diazepam, nordiazepam, midazolam, bromazepam, oxazepam, temazepam, lorazepam, clonazepam and alprazolam) have been determined in pericardial fluid. For this purpose a solid phase extraction (SPE) was carried out using Bond Elut Certify cartridges. After the derivatization of six of the nine benzodiazepines, gas chromatography coupled to a selective mass detector was used as the technique for the separation of the analytes. The method developed was fully validated for the 9 analytes and was applied to real samples of pericardial fluid received at the Forensic Toxicology Service of the University of Santiago de Compostela. Finally, they were compared with blood results looking for the existence of a possible correlation between both biological samples.

Fatal zolpidem poisoning due to its intravenous self-injection: Postmortem distribution/redistribution of zolpidem and its predominant metabolite zolpidem phenyl-4-carboxylic acid in body fluids and solid tissues in an autopsy case.

We experienced a curious fatal case, in which a male in his 20s self-administered zolpidem intravenously. The victim was found dead lying on floor of his apartment room, with a tourniquet band and new injection marks on his right forearm. Nearby the body, a medical disposal syringe containing small-volume solution dissolving crushed zolpidem tablets was found. The postmortem interval was estimated at about two days. The direct cause of his death was judged as asphyxia due to the aspiration of stomach contents into the trachea and bronchi. The specimens dealt with were body fluids and solid tissues including femoral vein blood, right and left heart blood, pericardial fluid, urine, bile, stomach contents, the brain, lung, heart muscle, liver, spleen, kidney, pancreas and skeletal muscle. For the extractions of zolpidem, zolpidem phenyl-4-carboxylic acid, deuterated internal standards zolpidem-d7 and zolpidem phenyl-4-carboxylic acid-d4, a modified QuEChERS method was used, followed by the analysis by liquid chromatography-tandem mass spectrometry. Because this study included various kinds of human matrices with quite different properties, the standard addition method was most preferable to overcome the matrix effects and recovery rates, and also did not need to use blank human matrices for validation experiments. The concentration of zolpidem and its phenyl-4-carboxylic acid metabolite in various specimens tested were generally extreme higher than those of reported fatal cases, supporting that the victim had died of intravenous zolpidem injection. The concentrations of zolpidem in femoral vein blood and right and left heart blood specimens in the present case were 9.55, 28.5 and 46.9µg/mL, respectively, which far exceeded estimated fatal levels. The present study also showed the postmortem distribution/redistribution of zolpidem and its phenyl-4-carboxylic acid metabolite in 15 body fluid and solid tissue specimens including stomach contents. Although a number of published literatures dealt with zolpidem poisoning cases due to oral ingestion of the drug, this is the first report on fatal intravenous zolpidem injection case and postmortem distribution of zolpidem and its predominant metabolite.

Can measurements of heroin metabolites in post-mortem matrices other than peripheral blood indicate if death was rapid or delayed?

BACKGROUND: In heroin-related deaths, it is often of interest to determine the approximate time span between intake of heroin and death, and to decide whether heroin or other opioids have been administered. In some autopsy cases, peripheral blood cannot be sampled due to decomposition, injuries or burns. The aim of the present study was to investigate whether measurements of heroin metabolites in matrices other than peripheral blood can be used to differentiate between rapid and delayed heroin deaths, and if morphine/codeine ratios measured in other matrices can separate heroin from codeine intakes. METHODS: In this study, we included 51 forensic autopsy cases where morphine was detected in peripheral blood. Samples were collected from peripheral and cardiac blood, pericardial fluid, psoas and lateral vastus muscles, vitreous humor and urine. The opioid analysis included 6-acetylmorphine (6-AM), morphine, morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G) and codeine. Urine was only used for qualitative detection of 6-AM. 45 heroin-intake cases were divided into rapid deaths (n=24), based on the detection of 6-AM in blood, or delayed deaths (n=21), where 6-AM was detected in at least one other matrix but not in blood. An additional 6 cases were classified as codeine-intake cases, based on a morphine/codeine ratio below unity (<1) in peripheral blood, without detecting 6-AM in any matrix. RESULTS: The median morphine concentrations were significantly higher in the rapid compared with the delayed heroin deaths in all matrices (p=0.004 for vitreous humor and p<0.001 for the other matrices). In the rapid heroin deaths, the M3G/morphine concentration ratios were significantly lower than in the delayed deaths both in peripheral and cardiac blood (p<0.001), as well as in pericardial fluid (p<0.001) and vitreous humor (p=0.006), but not in muscle. The morphine/codeine ratios measured in cardiac blood, pericardial fluid and the two muscle samples resembled the ratios in peripheral blood, although codeine was less often detected in other matrices than peripheral blood. CONCLUSIONS: Measurements of heroin-metabolites in cardiac blood, pericardial fluid and vitreous humor provide information comparable to that of peripheral blood regarding rapid and delayed heroin deaths, e.g. M3G/morphine ratios <2 indicate a rapid death while ratios >3 indicate a delayed death. However, considerable overlap in results from rapid and delayed deaths was observed, and measurements in muscle appeared less useful. Furthermore, matrices other than peripheral blood can be used to investigate morphine/codeine ratios, but vitreous humor seems less suited.