Heparin induced thrombocytopenia in patients with ventricular assistance device bridge-to-transplantation. A case series.

Heparin-induced thrombocytopenia (HIT), is a severe side effect of heparin. It occurs both in patients treated with unfractionated heparin (UFH) and in patients treated with low molecular weight heparin (LMWH). It is associated with anti-heparin/platelet factor (PF4) antibodies. HIT is a rare pathology, with rates going from 8% to 10% in patients in ventricular assist device support. The authors present three clinical cases which occurred in the Department of Anesthesiology of the Civil Hospital of Strasbourg (France) in patients receiving biventricular assistance bridge-to- cardiac transplantation. All the three patients were hospitalized for myocardial infarction. In case 1 HIT was diagnosed on VI day postoperative after a ventricular assistance device (VAD) implant. The patient was treated with lepirudin and transplanted after 73 days. In case 2 HIT diagnosis was made after 9 days receiving VAD. Also this patient was treated with lepirudin and transplanted after 48 days. Both case 1 and 2 received intra-aortic balloon pump (IABP) assistance before receiving VAD. Case 3 received VAD on XXII day of hospitalization; the patient developed HIT after 5 days, which was treated with lepirudin. He was transplanted after 66 days, but he died in course of intervention. HIT in patients undergoing VAD bridge-to-transplantation is a rare and often misdiagnosed cause of thrombocytopenia. Correct diagnosis, management and therapy are mandatory in this kind of patients, but they are not easy and standardized.

[Interest of the Mini Mental State Examination to detect cognitive defects after cardiac surgery]. / Intérêt du Mini Mental Test dans le dépistage des troubles cognitifs après chirurgie cardiaque.

INTRODUCTION: Cognitive defects are frequently described after cardiac surgery. They occur in 30 to 79% cases. They might be related to the use of a cardiopulmonary bypass (CPB). They are poorly evaluated in clinical practice. OBJECTIVES: To evaluate the usefulness of the Mini Mental State Examination (MMSE) to screen patients scheduled for cardiac surgery. STUDY DESIGN: Prospective, open study. PATIENTS AND METHODS: 100 consecutive patients undergoing coronary artery bypass or valvular replacement under CPB were enrolled in the study. The MMSE was performed the day before surgery and five days later. Patients exhiting a postoperative defect> or =4 points were compared to those without changes or with improved results. RESULTS: 73 patients completed both tests. The mean score decreased postoperatively in 12 patients (15%). They were older (70+/-8 years), had longer CBP durations (128+/-50 min) and the lowest temperatures (30 degrees C+/-3) compared to the other patients. At the opposite, five patients (9%) improved their scores. CONCLUSION: These results entourage to carry out a more strict follow-up for the oldest patients in cardiac surgery. The MMSE could be systematically integrated to the pre and postoperative screening. The detection of cognitive dysfunction should lead to address the patient to a geriatrician for a prolonged follow-up.

Endothelin participates in increased circulating atrial natriuretic peptide early after human heart transplantation.

BACKGROUND: Hemodynamic improvement after heart transplantation is expected to normalize the neuroendocrine balance, but circulating atrial natriuretic peptide (ANP) remains elevated. Endothelin stimulates ANP secretion and its concentration increases after heart transplantation, suggesting a role for this peptide in the cardiovascular adaptative response to heart transplantation. METHODS: To investigate whether endothelin may induce ANP increase in heart transplant recipients, we monitored daily ANP, endothelin, and related hormonal, biologic, and hemodynamic parameters before and during the first week after either heart transplantation (n = 15) or coronary artery bypass grafting (n = 10). RESULTS: Surgery induced a transient secretory peak of arginine vasopressin and endothelin in both groups at day 1. Bypass grafting did not modify normal ANP (11.8 +/- 2.1 pmol/L), endothelin (2.4 +/- 0.3 pmol/L), renin activity (0.11 +/- 0.04 pmol/L/sec), or aldosterone (492 +/- 122 pmol/L) values. Heart transplantation normalized the renin-aldosterone axis, but the early decrease observed for ANP (from 27.2 +/- 4.8 to 21.14 +/- 1.4 pmol/L) was only partial and transient. Endothelin further increased (from 4.4 +/- 0.8 to 9.14 +/- 1.8 pmol/L; p < 0.01) after transplantation. Positive correlations were observed between endothelin, isoproterenol dose, creatinine, right atrial pressure, and ANP, but multiple correlation analysis showed the important role of endothelin (r = 0.69, p < 0.001). Cyclic guanosine monophosphate correlated with ANP (r = 0.65, p < 0.001). CONCLUSIONS: Elevated endothelin, suggesting vascular dysfunction, likely contributes to the ANP increase observed early after heart transplantation. Furthermore, ANP, through a cardiac endothelium feedback, may act in the maintenance of circulatory homeostasis in heart transplant recipients.

Albumin-impregnated prosthetic graft for infrarenal aortic replacement: effects on the incidence and volume of perioperative blood transfusion.

We retrospectively reviewed 290 cases in which an albumin-impregnated polyester prosthetic graft was used for surgical management of aortic bifurcation disease between November 1987 and December 1990. The purpose of this review was to determine the incidence and volume of blood transfusion and to evaluate the rate of patency and the incidence of infection achieved using this type of prosthesis. The indication for surgery was abdominal aortic aneurysm (AAA) in 218 cases (190 elective procedures and 28 emergency procedures) and occlusive disease of the aortic bifurcation (ODAB) in 72 cases. Mean follow-up was 25.5 +/- 13.4 months (range: 1 and 50 months). The incidence of blood transfusion for elective AAA and ODAB surgery was 30.2% and 32.3% intraoperatively, 21.3% and 12.9% postoperatively, and 40.4% and 42.6% overall. The mean number of red cell packs transfused for elective AAA and ODAB surgery was respectively 1 and 0.8 intraoperatively, 0.4 and 0.6 postoperatively, and 1.4 and 1 overall. No immediate or late graft infection prosthesis was observed in any patient in this series. Primary and secondary patency was 95.5% and 97.5% at 6 months with no graft thrombosis during further follow-up. The fact that use of an impregnated graft in management of aortic bifurcation disease was accompanied by a high incidence and volume of blood transfusion suggests that these grafts do not reduce perioperative blood loss. Use of an impregnated prosthesis had no effect on the rate of patency and the incidence infection.

Contrast echocardiography in coronary artery diseased patients: effect of systemic and pulmonary artery pressures on left heart opacification after intravenous injection of Albunex.

BACKGROUND: Contrast echocardiography is a useful tool for assessing repeatedly patients with coronary artery disease. Nevertheless, elevated pulmonary artery and systemic blood pressures likely to be associated with cardiac ischemia may limit the left ventricular opacification (LVO) because of the microspheres' sensitivity to pressure. OBJECTIVE: To determine the effects of systemic and pulmonary artery blood pressures on LVO. METHODS: We performed 55 intravenous injections (0.08 and 0.22 ml/kg) of a new transpulmonary contrast agent (Albunex), during two separated exposures, into 20 cardiac ischemic patients while monitoring invasively their cardiac indexes, and intracardiac, systemic, and pulmonary artery blood pressures. LVO was graded qualitatively from faint to full. RESULTS: A logistic model with the grade of LVO as the dependent variable and a selection from among the dose, exposure, right and left atrial blood pressures, systolic systemic and pulmonary artery blood pressures (ranges 94-208 and 14-45 mmHg, respectively), cardiac index, stroke index, and pulmonary and systemic vascular resistances as the explanatory variables demonstrated that increasing the dose gives an increasing probability of LVO (P = 0.02) and that increasing the pulmonary artery pressure reduces that probability (P = 0.006). A decreased cardiac index tended also to be associated with decreased LVO. The systemic blood pressure and the pulmonary and systemic vascular resistances had no statistically significant effect on the grade of LVO. CONCLUSIONS: LVO after intravenous administration of Albunex is dose-dependent and limited by an elevated pulmonary artery pressure. These data suggest that one should use higher doses for cardiac ischemic patients with elevated pulmonary artery pressures and that use of Albunex has the potential to detect pulmonary hypertension in patients.

Safety of a new transpulmonary echocontrast agent (Albunex) in repeated echocardiographic studies in patients.

BACKGROUND AND HYPOTHESIS: Multiple contrast-enhanced echocardiographic studies are to be expected in patients with cardiac ischemic disease, but the sonication process used to produce the echocontrast agent Albunex may result in new epitopes that could cause an immunogenic response. METHODS: Repeated exposures to intravenous Albunex over a period of time long enough to allow development of an eventual immune reaction were performed in 12 patients while monitoring for lymphocyte transformation, microsphere specific IgE and IgG antibodies, and systemic, pulmonary artery, capillary wedge, and right atrial pressures, as well as cardiac output, left ventricular fractional shortening, and blood gases. RESULTS: No significant 3H-thymidine incorporation and thus no specific blastic transformation of the patients' lymphocytes were observed either for high or low Albunex concentrations, corresponding to the expected hepatic and plasma concentrations of microspheres. No formation of microsphere-specific IgE and IgG antibodies was observed after the first or second Albunex exposure. Furthermore, no clinically significant hemodynamic or respiratory adverse reactions were observed in any patient. CONCLUSION: These results suggest that repeated exposures to intravenous Albunex induce no adverse effect on the cellular and humoral immune systems and on left and right heart hemodynamics in patients.

[Evaluation of coronary risk in patients with subrenal abdominal aortic aneurysm]. / Evaluation du risque coronarien chez les patients présentant un anévrysme de l'aorte abdominale sous-rénale.

Atheroma lesions are often found in multiple localizations. In addition, operative mortality for aneurysms of the non-ruptured sub-renal aorta is mainly related to coronary risk. In an attempt to reduce coronary risk, coronarography was performed in all patients (n = 297) from January 1989. Operation for the aneurysm was performed in 192 patients (reasons for not operating were small size of the aneurysm, other contraindication). There were 5 deaths, all related to coronary artery disease. Coronary bypass was performed in 42 patients either before (n = 38) or at the same time (n = 4) as the operation for the aneurysm of the aorta. There were no operative deaths. These results clearly demonstrate the importance of search and treatment of associated coronary lesions in all patients with an aneurysm of the subrenal abdominal aorta. Coronary lesions should be treated whenever morphology allows.

Does carotid eversion endarterectomy and reimplantation reduce the risk of restenosis?

Two hundred twelve eversion endarterectomies of the internal carotid artery and reimplantation in the common carotid artery were performed between January 1985 and July 1990. A total of 206 patients with stenosis of 75% or more and with redundancy and tortuosity of the internal carotid artery underwent this procedure. Cumulative mortality and neurologic morbidity were 2.4%. Forty patients died during the course of follow-up, seven of neurologic causes (17.1%). Duplex scans of 107 operated carotid arteries were obtained an average of 27.1 months after surgery. Restenosis of > 50% was encountered in three patients (1.9%), two asymptomatic patients (1.3%) with > 75% restenosis and one symptomatic patient with occlusion (0.6%). These results contrast with a 13.5% rate of restenoses > 50% (including 5.9% of restenoses > 75% and 1.7% occlusions) observed after 156 consecutive endarterectomies performed and closed by direct suture by the same surgical team in 1987 at a mean follow-up of 44 months. We believe that this technique can be used more often because the the operative and long-term risks are not any greater than those of the other methods of carotid revascularization. Eversion endarterectomy associated with reimplantation is especially indicated when the internal carotid artery is elongated, is < 4 mm wide, and occurs in women.

[Acute dissection of the ascending aorta. Can the risk of reoperation be reduced?]. / Dissection aiguë de l'aorte ascendante. Peut-on réduire le risque de réintervention?

From January 1974 to October 1993, we operated 113 Stanford type A acute dissections of the ascending aorta. There were 19 cases of immediate death but overall mortality was low (17%). During the last 10 years, mortality was reduced to 12%. There were 94 survivors who were followed for 2 months to 19.2 years. Mean follow-up was 6.6 +/- 4.77 years. Total follow-up time was 583 patients/years. There were 21 secondary deaths occurring within 2 months of surgery and the 10th post-operative year. Actuarial survival rate, including operative mortality, was 80 +/- 3.7% at 1 year, 70 +/- 4.6% at 5 years and 53 +/- 6% at 10 years. There were 17 vascular complications during the follow-up including 12 requiring reoperation. There were no vascular complications in 90% of the patients at 3 years, 78% at 6 years and 60% at 10 years. Three cases of aortic insufficiency developed subsequently and required reoperation with prosthetic valve replacement. Operative techniques changed between the first and second decade of this series. During the second decade, cardioplegic protection of the myocardium, open distal anastomosis, systematic exploration of the aortic arch and finally extension of the resection to the isthmus when required were introduced successively. In the absence of sufficient follow-up in the patients operated during the second decade, it is not possible to establish whether these modifications have actually reduced the number of post-operative vascular complications commonly reported.

[Embolectomy in massive lung embolism]. / Embolektomie bei massiver Lungenembolie.

Pulmonary embolism was first described by Laennec in 1819. After introduction of the Trendelenburg surgical technique, Kirschner, in 1925, performed the first successful embolectomy. In a review of the literature, in 42 patients, survival rate was 45% on use of a modified Trendelenburg method employing cross-clamping of the vena cava. The use of this intervention can still be considered justified if extracorporeal circulation is not available. Establishment of the indication and anatomical fundamentals The indication for surgical embolectomy is considered established in the presence of massive pulmonary arterial obstruction with pending death of the patient. The difficulty lies in identification of the patient with massive pulmonary embolism who will succumb and in defining the extent of pulmonary arterial obstruction which will lead to death. Limitation of the indication to only those patients in shock led to mortality rates up to 93%. Immediate death after pulmonary embolism is not the rule. Of 52 patients with massive pulmonary embolism, 50% survived more than two hours; in those with no preexistent cardiopulmonary disease up to eight hours. Surgical intervention can be considered accordingly. Anatomically, massive pulmonary embolism implies at least 60 to 70% obstruction of the pulmonary arterial bed. In 85 of 100 patients who died of pulmonary embolism, voluminous emboli were found in both pulmonary arteries. In the presence of preexistent cardiopulmonary disease, lesser degrees of obstruction can lead to a critical condition. In consideration of the indication as above, the following comments are considered appropriate: 1. Quantification of the obstruction: Pulmonary angiography remains the most appropriate diagnostic examination. The degree of obstruction can be quantified according to a number of indices. As of 60%-obstruction, surgical intervention can be considered. 2. Justification of embolectomy: The classical indication can be established in 2 to 6% of the patients based on treatment-refractory hypotension. In Table 1, the classical stages of massive pulmonary embolism are shown with the indication for embolectomy being considered as of stage IV but these characteristics are unreliable in everyday practice. If surgery is delayed until vasoactive drugs are no longer effective, an irreversible condition is frequently incurred in spite of operative removal of the obstruction. More favorable results can be achieved when the indication for surgery is based only on the degree of obstruction since, in this case, the condition of shock will not be prolonged and a hemodynamically-stable patient can be subjected to surgery. 3. Thrombolytic treatment

[Long-term course of syphilitic aortic insufficiency with ostial stenosis following surgical treatment]. / Evolution à long terme, après traitement chirurgical, des insuffisances aortiques avec sténoses ostiales d'origine syphilitique.

Syphilitic aortic insufficiency and coronary ostial stenosis is a rare condition. It was diagnosed in 8 patients referred for surgery. The infection, acknowledged in 3 cases, was contracted over 15 years prior to admission! The operative indication was aortic valve replacement in 6 cases (Stage II to IV dyspnoea) and coronary insufficiency in 2 cases (Stage III angina pectoris). Two cases of ostial stenosis were not identified at coronary angiography, illustrating the potential diagnostic pitfall of a disease which is often unrecognised nowadays. Preoperative echocardiography of the left main coronary artery, especially its intra-aortic segment, may be of value but was not performed in these old cases. Surgery consisted in aortic valve replacement and coronary revascularisation by decortication of the ostia or coronary bypass (1 case). The evolution was excellent in the 6 survivors, especially with respect to the anginal syndrome which was completely cured without associated treatment. A protocol of echocardiographic surveillance of the left main coronary artery has been instituted in these patients to detect any late postoperative changes after ostial decortication.

[Bronchospasm during extracorporeal circulation]. / Bronchospasme en cours de circulation extracorporelle.

Six cases of bronchospasm are reported, which occurred at the end of cardiopulmonary bypass (CPB). One patient developed this condition twice within one year. This was a rare occurrence (6 cases for 3714 CPB). Symptoms were the same every time: increased inflation pressures, impossible deflation, and low left atrial pressures. Adrenaline given by way of the bypass was the quickest and most effective treatment. The favourable outcome in all 5 patients was due to the continuing of circulatory assistance by the CPB. Although the prevention of anaphylactoid accidents in atopic patients has been well documented, the cause of the bronchospasm in our patients has not been recognized, and it may well not have been due to a particular drug.