Arterial and venous blood sampling is equally applicable for coagulation and fibrinolysis analyses.

OBJECTIVES: No consensus exists upon whether arterial and venous blood samples are equivalent when it comes to coagulation analyses. We therefore conducted a comparative cohort study to clarify if arteriovenous differences affect analyses of primary and secondary hemostasis as well as fibrinolysis. METHODS: Simultaneous paired blood samplings were obtained from a cannula in the radial artery and an antecubital venipuncture in 100 patients immediately before or one day after thoracic surgery. Analyses of platelet count and aggregation, International Normalized Ratio (INR), activated partial thromboplastin time (APTT), antithrombin, thrombin time, fibrinogen, D-dimer, rotational thromboelastometry (ROTEM), thrombin generation, prothrombin fragment 1 + 2, and an in-house dynamic fibrin clot formation and lysis assay were performed. RESULTS: No differences were found between arterial and venous samples for the far majority of parameters. The only differences were found in INR, median (IQR): venous, 1.1 (0.2) vs. arterial, 1.1 (0.2) (p<0.002) and in prothrombin fragment 1 + 2: venous, 289 (209) pmol/L vs. arterial, 279 (191) pmol/L (p<0.002). CONCLUSIONS: The sampling site does not affect the majority of coagulation analyses. Small differences were found for two parameters. Due to numerically very discrete differences, they are of no clinical relevance. In conclusion, the present data suggest that both samples obtained from arterial and venous blood may be applied for analyses of coagulation and fibrinolysis.

Mechanical circulatory support for refractory out-of-hospital cardiac arrest: a Danish nationwide multicenter study.

BACKGROUND: Mechanical circulatory support (MCS) with either extracorporeal membrane oxygenation or Impella has shown potential as a salvage therapy for patients with refractory out-of-hospital cardiac arrest (OHCA). The objective of this study was to describe the gradual implementation, survival and adherence to the national consensus with respect to use of MCS for OHCA in Denmark, and to identify factors associated with outcome. METHODS: This retrospective, observational cohort study included patients receiving MCS for OHCA at all tertiary cardiac arrest centers (n = 4) in Denmark between July 2011 and December 2020. Logistic regression and Kaplan-Meier survival analysis were used to determine association with outcome. Outcome was presented as survival to hospital discharge with good neurological outcome, 30-day survival and predictors of 30-day mortality. RESULTS: A total of 259 patients were included in the study. Thirty-day survival was 26%. Sixty-five (25%) survived to hospital discharge and a good neurological outcome (Glasgow-Pittsburgh Cerebral Performance Categories 1-2) was observed in 94% of these patients. Strict adherence to the national consensus showed a 30-day survival rate of 30% compared with 22% in patients violating one or more criteria. Adding criteria to the national consensus such as signs of life during cardiopulmonary resuscitation (CPR), pre-hospital low-flow < 100 min, pH > 6.8 and lactate < 15 mmol/L increased the survival rate to 48%, but would exclude 58% of the survivors from the current cohort. Logistic regression identified asystole (RR 1.36, 95% CI 1.18-1.57), pulseless electrical activity (RR 1.20, 95% CI 1.03-1.41), initial pH < 6.8 (RR 1.28, 95% CI 1.12-1.46) and lactate levels > 15 mmol/L (RR 1.16, 95% CI 1.16-1.53) as factors associated with increased risk of 30-day mortality. Patients presenting signs of life during CPR had reduced risk of 30-day mortality (RR 0.63, 95% CI 0.52-0.76). CONCLUSIONS: A high survival rate with a good neurological outcome was observed in this Danish population of patients treated with MCS for OHCA. Stringent patient selection for MCS may produce higher survival rates but potentially withholds life-saving treatment in a significant proportion of survivors.

Blood cardioplegia benefits only patients with a long cross-clamp time.

INTRODUCTION: A clear advantage of blood versus crystalloid cardioplegia has not yet been observed in smaller population studies. The purpose of this article was to further investigate the clinical outcomes of blood versus crystalloid cardioplegia in a large propensity-matched cohort of patients who underwent cardiac surgery. METHODS: The study was a single-centre study. Data was withdrawn from the Western Denmark Heart Registry, which comprises a perfusion section for each procedure. A total of 4,852 patients were propensity matched into crystalloid (CC) vs blood cardioplegia (BC) groups. The primary end points were creatinine kinase-MB (CKMB) elevation, acute myocardial infarction (AMI), stroke, dialysis, coronary angiography (CAG) and mortality (30 days and 6 months). RESULTS: We found lower odds ratio in 30-day mortality in the BC group (OR 0.21; CI 0.06-0.68), but no difference in overall 6-month mortality. There was no difference in CKMB elevation, AMI, dialysis or stroke. Several end points were further analysed for different cross-clamp times. In the CC group, ventilation time above 600 minutes was seen more often in almost all cross-clamp time intervals (23.5 % vs 12.2 %; p<0.0001; χ2-test) and 6-month mortality was significantly higher when the cross-clamp time exceeded 210 minutes (64.3 vs 23.8; p=0.018; χ2-test). CONCLUSIONS: We did not find clear evidence of superiority of either type in the uncomplicated patient. When prolonged cross-clamp time or postoperative ventilation is expected, this study indicates that blood cardioplegia might be preferable.

Impact of minimally invasive extracorporeal circulation on coagulation-a randomized trial.

OBJECTIVES: Minimally invasive extracorporeal circulation (MiECC) is suggested to have favourable impact on blood loss compared to conventional extracorporeal circulation. We aimed to compare the impact of both systems on coagulation. METHODS: Randomized trial comparing endogenous thrombin-generating potential early after elective coronary surgery employing either MiECC group (n = 30) or conventional extracorporeal circulation group (n = 30). Secondary outcomes were in vivo thrombin generation, bleeding end points and haemodilution, as well as morbidity and mortality up to 30-day follow-up. RESULTS: Compared to the conventional extracorporeal circulation group, the MiECC group showed (i) a trend towards a higher early postoperative endogenous thrombin-generating potential (P = 0.06), (ii) lower intraoperative levels of thrombin-antithrombin complex and prothrombin fragment 1 + 2 (P < 0.001), (iii) less haemodilution early postoperatively as measured by haematocrit and weight gain, but without correlation to coagulation factors or bleeding end points. Moreover, half as many patients required postoperative blood transfusion in the MiECC group (17% vs 37%, P = 0.14), although postoperative blood loss did not differ between groups (P = 0.84). Thrombin-antithrombin complex levels (rs = 0.36, P = 0.005) and prothrombin fragment 1 + 2 (rs = 0.45, P < 0.001), but not early postoperative endogenous thrombin-generating potential (rs = 0.05, P = 0.72), showed significant correlation to increased transfusion requirements. The MiECC group demonstrated significantly lower levels of creatine kinase-MB, lactate dehydrogenase and free haemoglobin indicating superior myocardial protection, less tissue damage and less haemolysis, respectively. Perioperative morbidity and 30-day mortality did not differ between groups. CONCLUSIONS: Conventional but not MiECC is associated with significant intraoperative thrombin generation despite full heparinization. No correlation between coagulation factors or bleeding end points with the degree of haemodilution could be ascertained. CLINICALTRIALS.GOV IDENTIFIER: NCT03216720.

High-pressure balloon fracturing of small dysfunctional Mitroflow bioprostheses facilitates transcatheter aortic valve-in-valve implantation.

AIMS: Transcatheter valve-in-valve (VIV) implantation is usually discouraged in small surgical tissue valves. We report our first ten cases of fracturing small dysfunctional Mitroflow bioprostheses by high-pressure balloon dilatation to increase the internal diameter of the surgical valve before VIV (BF-VIV). METHODS AND RESULTS: BF-VIV was performed in 10 patients (mean age 84±4 years) with failing Mitroflow valves size 19 mm (n=3, threshold of fracture 15 atm) and 21 mm (n=7, threshold of fracture 13 atm). An Edwards SAPIEN 3 or XT 20 mm or 23 mm transcatheter valve was implanted inside the fractured Mitroflow bioprosthesis. The procedure improved aortic valve area (0.7±0.3 vs. 1.1±0.3 cm2, p=0.001), reduced peak aortic valve gradient (66±27 vs. 29±7 mmHg, p=0.002), resolved aortic regurgitation and improved patients' NYHA functional class (p=0.005). One patient had a minor stroke with complete resolution of symptoms and another patient required a pacemaker due to AV block. All patients were still alive at the end of follow-up (438±255 days). CONCLUSIONS: Initial experience with transcatheter BF-VIV suggests that this method is feasible and safe, and that it improves aortic valve haemodynamics and clinical functional capacity. BF-VIV is a promising alternative to repeat surgery in patients with small failing Mitroflow bioprostheses.

[High-risk pregnancy in a woman with Marfan syndrome, a bicuspid aortic valve, and a dilated aortic sinus]. / Højrisikograviditet hos en kvinde med Marfans syndrom, bikuspid aortaklap og aortaektasi.

A 29-year-old woman with Marfan syndrome, a bicuspid aortic valve, and a dilated aortic sinus (5.2 cm) presented herself in clinic 14 weeks pregnant. She was advised to discontinue the pregnancy due to risk of dissection; however, she decided to continue. She was treated with labetalol (300 mg/day) to reduce blood pressure and was admitted for bed rest from week 30. Her aortic diameter was assessed by echocardiography every 2nd week and remained unchanged. She was treated with betamethason at week 26 and the child was born by a caesarean section in week 35. The post-operative course was uneventful.