Jean-Philippe Mazzucotelli

Plasma fibrinogen level on admission to the intensive care unit is a powerful predictor of postoperative bleeding after cardiac surgery with cardiopulmonary bypass

INTRODUCTION Evidence regarding the behavior of fibrinogen levels and the relation between fibrinogen levels and postoperative bleeding is limited in cardiac surgery under cardiopulmonary bypass (CPB). To evaluate perioperative fibrinogen levels as a predictor of postoperative bleeding in patients undergoing cardiac surgery with CPB. MATERIALS AND METHODS In this prospective, single-center, observational cohort study of 1956 patients following cardiac surgery with CPB, fibrinogen level was measured perioperatively. Excessive bleeding group was defined as patients with a 24-h chest tube output (CTO) exceeded the 90th percentile of distribution. RESULTS The median 24-h CTO was 728.6±431.1ml. A total of 189 patients (9.7%) were identified as having excessive bleeding. At admission to the intensive care (Day 0), the fibrinogen levels were 2.5±0.8g/l and 2.1±0.8g/l in the control and excessive bleeding groups, respectively (P<0.0001). The fibrinogen level on Day 0 was significantly correlated with the 24-h CTO (rho=-0.237; P<0.0001). Multivariate analysis demonstrated that the fibrinogen level at Day 0 was the best perioperative standard laboratory test to predict excessive bleeding (P=0.0001; odds ratio, 0.5), whereas preoperative fibrinogen level was not a predictor. Using receiver operating characteristics curve analyses, the best Day 0 fibrinogen level cutoff to predict postoperative bleeding was 2.2g/l. CONCLUSIONS In this large prospective study, the fibrinogen level upon admission to the intensive care unit after CPB predicted the risk of postoperative bleeding. Our data add to the concern regarding the fibrinogen level threshold that might require fibrinogen concentrate infusion to reduce postoperative blood loss.

Lower circulating Sta-Liatest D-Di levels in patients with aortic intramural hematoma compared with classical aortic dissection

Objective:To compare the diagnostic value of circulating Sta-Liatest D-Di levels in classic acute aortic dissection (AAD) and in aortic intramural hematoma (AIH), a variant of AAD without a patent false lumen. Design:Single-center retrospective case-control study. Setting:University Hospital of Strasbourg, France. Patients:Ninety-four consecutive patients with both confirmed AAD and d-dimer measurements at entry were included. d-dimer levels were assayed by the immunoturbidimetric method Sta-Liatest D-Di (Diagnostica Stago, Asnieres sur Seine, France). Intervention:Patient characteristics and clinical evolution were analyzed. Measurements and Main Results:Eighty-four patients (89%) presented a classic AAD with patent false lumen and ten (11%) presented an AIH. Clinical presentation did not differ between the two groups. The mortality rate was 0% in AIH and 26% in classic AAD. d-dimer levels were significantly lower in patients with AIH (median, 1230 ng/mL; interquartile range, 685–2645 ng/mL) than in patients with AAD with patent false lumen (median value, 9290 ng/mL; interquartile range, 3890–20,000 ng/mL; p = 0.008). All patients with AAD and patent false lumen had d-dimer levels above the threshold of 400 ng/mL (sensitivity 100%). However, one patient with AIH presented d-dimer levels below the threshold. Therefore, the sensitivity of the d-dimer test in detecting AIH was 90%. Conclusions:Sta-Liatest D-Di levels are lower in AIH than in AAD with patent false lumen. This test can quite possibly be negative in the case of intramural hematoma. This feature must be considered when interpreting d-dimer levels in patients with acute aortic syndrome.

Durability of the mitroflow pericardial valve at ten years

From 1983 to 1992, 366 patients received 407 Mitroflow pericardial valves. Mean age was 62 +/- 14 years. Average follow-up was 72 +/- 28 months. Total follow-up was 1,791 patient-years. Overall survival in all patients was 77.2% +/- 2.2% at 5 years and 56.2% +/- 6.4% at 10 years. Freedom from structural valve deterioration was 95% +/- 1.2% and 36.7% +/- 8.1% at 5 and 10 years for all valves, 96.9% +/- 1.3% and 39.2% +/- 9.8% for aortic valve replacement, and 91.7% +/- 3.2% and 36.4% +/- 10% for mitral valve replacement (p = not significant). The freedom from structural valve deterioration in patients older than 70 years of age was 100% and 93.9% +/- 5.8% at 5 and 10 years, respectively. At 10 years, linearized rate of thromboembolism was 0.73% +/- 0.2% per patient-year and freedom from valve-related mortality for all valves was 88.8% +/- 2.8%. The best indication for the implantation of a Mitroflow valve is mitral or aortic disease in patients more than 70 years of age.

Remote and local ischemic postconditioning further impaired skeletal muscle mitochondrial function after ischemia-reperfusion

OBJECTIVE Muscular injuries contribute to perioperative and long-term morbidity after vascular surgery in humans. We determined whether local and remote ischemic postconditioning might similarly decrease muscle mitochondrial dysfunction through reduced oxidative stress. METHODS Eighteen male Black-6 mice were divided in three groups: (1) sham mice had no ischemia (sham), (2) ischemia-reperfusion (IR) mice underwent 2-hour tourniquet-induced ischemia on both hind limbs, followed by 2-hour reperfusion, and (3) postconditioning (PoC) mice underwent four bouts of 30-second reperfusion and 30-second ischemia at the onset of reperfusion on the right limb; thus, the right limb underwent local PoC and left limb underwent remote PoC (rPoC). Maximal oxidative capacity (V(max)) of the gastrocnemius muscle mitochondrial respiratory chain was measured. Oxidative stress was evaluated by dihydroethidium staining. Expressions of genes involved in antioxidant defense (superoxide dismutase [SOD1], SOD2, glutathione peroxidase [GPx]), apoptosis (Bax, BclII), and inflammation (interleukin-6) were determined by quantitative real-time polymerase chain reaction. Muscle inflammation was determined using immunohistochemistry. RESULTS IR reduced V(max) (8.5 ± 2.2 vs 10.2 ± 1.8 μmol O(2)/min/g dry weight; P = .034), and increased dihydroethidium staining (134.8%; P = .039). IR decreased GPx expression (-47.9%; P = .048) and increased the proapoptotic marker Bax (255.5%; P = .020). Local PoC and rPoC further increased these deleterious effects. PoC decreased V(max) to 4.4 ± 1.4 μmol O(2)/min/g dry weight (sham vs PoC, -56.9% [P < .001]; IR vs PoC, -48.2% [P < .001]). rPoC similarly reduced V(max) to 5.1 ± 1.9 μmol O(2)/min/g dry weight (sham vs PoC, -50.0% [P < .001]; IR vs PoC, -40.0% [P = .001]). Dihydroethidium staining was further increased by PoC (207.2%; P = .002) and rPoC (305.4%; P < .001) compared with sham and was associated with macrophage infiltration. Local PoC increased SOD1, SOD2, and the antiapoptotic Bcl-2, and rPoC increased Bax (391.6%; P < .001) and the Bax/BclII ratio (621.7%; P < .001). CONCLUSIONS Local and remote ischemic postconditioning further increased injury by enhancing mitochondrial dysfunction, oxidative stress production, and inflammation. Caution should be applied when considering ischemic postconditioning in vascular surgery.

Mechanical bridge to transplantation: When is too early? When is too late?

BACKGROUND Optimal timing of implantation of a mechanical circulatory support system in the treatment of acute cardiogenic shock is still unsettled. The issue has been addressed in a retrospective analysis of a group of 98 patients in cardiogenic shock refractory to medical therapy who were candidates for cardiac transplantation, admitted from 1987 to 1994. METHODS The treatment included reinforced inotropic support by addition of phosphodiesterase inhibitors to sympathomimetic agents. The patients who did not improve were immediately brought to the operating room for mechanical circulatory support system implantation. RESULTS The overall survival in the group of 28 patients selected for mechanical bridge is 50%. No predictive factors of death or multiorgan failure while on the device could be identified, suggesting a lack of contraindications to mechanical circulatory support system implantation. CONCLUSIONS The high death rate in patients maintained on medical therapy because of initial improvement as they are awaiting transplantation suggests the benefit of a rapid semielective implantation of an intracorporeal device.

Mitroflow pericardial valve: long-term durability.

Isolated aortic (n = 107), mitral (n = 63), and tricuspid (n = 1) valve replacement and 28 double-valve replacements were performed with a second generation of pericardial valves, the Mitroflow valve, in 199 patients from March 1983 to December 1986. Follow-up (total, 1,058 patient-years) was extended to 106 months and 91.5% complete. Mean age was 58 +/- 13 years. The operative mortality included 22 deaths, non-cardiac-related in 7. The actuarial probability of survival for all patients was 66% +/- 4% at 8.5 years. There were no significant differences between patients with aortic valve replacement, mitral valve replacement, or double-valve replacement. The rate of thromboembolic events, antithromboembolic therapy-related hemorrhage, periprosthetic leak, and endocarditis is extremely minimal. Structural valve dysfunction occurred at a rate of 3.2% +/- 0.5%/patient-year. Actuarial freedom from the event was 94.6% +/- 1.7% at 5 years and 63.7% +/- 6.5% at 8.5 years for all valves. There were no difference in structural valve dysfunction rate between patients having aortic, mitral, or double-valve replacement. Thirty-five patients were reoperated on (3.4 +/- 0.6%/patient-year for all). The rate of all valve-related morbidity and mortality was 5.6% +/- 0.7%/patient-year for all patients, actuarial freedom from the event being 44% +/- 7% at 8.5 years. These data suggest that the excellent hemodynamic characteristics of the valve are balanced by a risk of valve failure that is slightly increased when compared with porcine valves.

Pharmacological bridge to cardiac transplantation: Current limitations

Addition of intravenous enoximone to sympathomimetic agents permits a rapid and drastic improvement in the clinical and hemodynamical condition of patients in cardiogenic shock referred for a mechanical bridge to transplantation. The present experience, based on the management of 52 patients, permits us to point out the current limitations of this pharmacological bridge: the rate of sudden death, the incompleteness of the physical rehabilitation of the patients, and the vanishing effect of intravenous enoximone.

Right Atrial Metastasis From Hepatocellular Carcinoma

Abstract  A 65‐year‐old patient with a past medical history of hypertension, alcoholism, micronodular cirrhosis, and coronary artery bypass grafting 10 years ago developed a hepatocellular carcinoma, treated by chemoembolization. One month after treatment, thoracoabdominal CT scan showed no residual hepatic tumor, but tumoral aspect in the right atrium with extension into the inferior vena cava. The patient being asymptomatic, cardiac ultrasound confirmed the presence of a free, mobile, pediculated tumor in the right atrium. Surgical exploration found a well‐circumscribed mass, attached to the atrial wall by a 1.5‐cm diameter pedicle implanted near the inferior vena cava ostium, moving freely in the right atrial cavity. The tumor was easily resected by section of the pedicle and its surrounding parietal implantation zone. No complications occurred postoperatively, and the patient was discharged on the 10th postoperative day. Three years after, the patient is in good health and is asymptomatic; cardiac ultrasound showed no tumor recurrence.

Coronary artery response to cold-pressor test is impaired early after operation in heart transplant recipients☆

OBJECTIVES The aim of the present study was to evaluate the coronary vasomotor response to the cold-pressor test within 3 months after heart transplantation. BACKGROUND Normal epicardial coronary arteries dilate in response to sympathetic stimulation evoked by the cold-pressor test. In transplant recipients, abnormal coronary vasomotion has been described shortly after operation. METHODS Fourteen heart transplant recipients were compared 52 +/- 15 days (mean +/- SD) after operation with 10 control subjects. All had angiographically normal epicardial coronary arteries. Coronary blood flow velocity was measured with a Doppler catheter placed in the proximal left anterior descending coronary artery. Four segments in each patient were analyzed by quantitative coronary angiography to assess the diameter changes during the cold-pressor test and after intracoronary injection of isosorbide dinitrate. RESULTS Coronary flow velocity increased similarly during the cold-pressor test in control subjects and in transplant recipients, from 7.5 +/- 2.3 to 11.0 +/- 3.9 cm/s and from 10.3 +/- 3.2 to 13.7 +/- 4.8 cm/s (both p < 0.01). In control subjects, 39 of 40 segments analyzed dilated during the cold-pressor test. In transplant recipients, 48 of 56 segments analyzed did not change or constricted. The mean epicardial coronary diameter increased significantly during the cold-pressor test in control subjects (+13 +/- 6%, p < 0.001), whereas it did not change significantly in transplant recipients (-2 +/- 9%, p = NS). In transplant recipients, isosorbide dinitrate elicited coronary vasodilation similar to that in control subjects. CONCLUSIONS These data indicate that in human transplanted denervated hearts, coronary vasodilation in response to sympathetic stimulation by cold exposure is impaired shortly after operation.

D-Dimer in ruling out acute aortic dissection: sensitivity is not 100%

We read with great interest the article by Sodeck et al. 1 reporting the negative predictive value of D-Dimer in acute aortic dissection (AAD). Based on a meta-analysis and on a personal series of 65 patients, the authors conclude that current evidence supports a routine measurement of D-Dimer for excluding AAD. Furthermore, a D-Dimer threshold <0.1 µg/mL would exclude AAD in all cases. We previously reported on a 94-case series of patients2 and believe for several reasons that Sodecks conclusion could …