Pulmonary Embolism in Transit

A 65-year-old woman with recently diagnosed ovarian cancer presented with near syncope, tachypnea, and hypoxia. Transthoracic echocardiography revealed a dilated and hypokinetic right ventricle and a large, mobile mass in the right atrium prolapsing across the tricuspid valve. She was diagnosed with pulmonary embolism in transit and emergent embolectomy was recommended

Pre-rift evolution of Malawian high-grade basement rocks

There is some controversy in terms of the basement geology of Malawi which ultimately stems from the overall lack of metamorphic studies conducted in the area. The geological complexity of Malawi comes from that fact that it sits at the intersection of three major orogenic belts: The Palaeoproterozoic Ubendian Belt, Mesoproterozoic Kibaran/Irumide Belt, and Pan African Mozambique Belt. Its complexity makes it difficult to unravel, especially in terms of identifying features of older orogenic events which have already experienced multiple metamorphic overprinting from subsequent events. This thesis provides a more detailed pre-rift evolution of the Malawian basement rocks by reporting ages and P-T conditions from four localities surrounding Lake Malawi, namely Chilumba, Mlowe, Maganga, and Mangochi. Results reveal that at 1985-1974 Ma, garnet-cordierite granulites were equilibrated under conditions of 760°C at 4.5-5 kbar possibly as a result of subduction-related magmatism. Subsequently, at 1100 Ma, charnockites were emplaced and metamorphosed under peak conditions of 770-780°C at 4.3-6 kbar due to Kibaran-age magmatic underplating. Remnants of the Irumide/Kibaran Orogeny is relatively scarce throughout Malawi and although the Mangochi charnockites were emplaced during Kibaran-age tectonism, it also experienced at least two different metamorphic events thereafter. The first occurred either during early stages of the East African orogen or Rodinia break-up at 900-800 Ma while the second occurred during the late stages of the East African orogen at 650-600 Ma. Possible remnants of the Kuunga Orogeny are recorded in Chilumba and Maganga as an amphibolite facies metamorphic event which took place around 570 Ma under peak conditions of roughly 660-670°C at 6-8 kbar. Findings of this study have not only provided a more detailed metamorphic history of Malawi but also paved way for future studies in the area to further explore why similar rocks found in such close proximity to each other preserve vastly different tectonic environments

Platelet anesthesia with nitric oxide with or without eptifibatide during cardiopulmonary bypass in baboons

AbstractObjective:This study tested the hypothesis that nitric oxide or nitric oxide and eptifibatide (Integrilin) reversibly inhibit platelet activation and consumption during cardiopulmonary bypass and rapidly restore platelet numbers and function after bypass. Methods: Nitric oxide, a short-acting, reversible platelet inhibitor, was studied with and without eptifibatide, a short-acting, reversible glycoprotein IIb/IIIa inhibitor, in 21 baboons that underwent 60 minutes of normothermic cardiopulmonary bypass with peripheral cannulas. A control group, a group that received 80 ppm nitric oxide, and a group that received both nitric oxide and eptifibatide were studied. Blood samples were obtained at several time points to determine platelet count, aggregation in response to adenosine diphosphate, and levels of β-thromboglobulin, prothrombin fragment 1.2, and thrombin-antithrombin complex. Template bleeding times were measured before and at 4 intervals after cardiopulmonary bypass. Results: Both nitric oxide and the combination of the 2 drugs significantly attenuated platelet consumption, improved postbypass function, and reduced plasma β-thromboglobulin release with respect to values in control animals. Both nitric oxide and the combination restored baseline bleeding times 55 minutes after cardiopulmonary bypass ended. No significant differences between nitric oxide and the combination were found for any measurement. Conclusion: Nitric oxide with or without eptifibatide protects platelets during cardiopulmonary bypass and accelerates restoration of normal bleeding times after operation in a baboon model. Although nitric oxide and eptifibatide reversibly inhibit platelets by different mechanisms, in the absence of a wound no synergistic effect was demonstrated. (J Thorac Cardiovasc Surg 1999;117: 987-93

Transmyocardial laser revascularization fails to prevent left ventricular functional deterioration and aneurysm formation after acute myocardial infarction in sheep

AbstractObjective: Transmyocardial laser revascularization is an investigational technique for revascularizing ischemic myocardium in patients with inoperable coronary arterial disease. This study tests the hypothesis that laser revascularization prevents left ventricular functional deterioration and aneurysm formation after acute anteroapical myocardial infarction. Methods: An ultrasonic ascending aortic flow probe and snares around the distal left anterior descending and second diagonal coronary arteries were placed in 26 Dorsett hybrid sheep. Ten to 14 days later, snared arteries were occluded to produce an anteroapical infarction of 23% of left ventricular mass. Before infarction 14 animals had 34 ± 4 transmyocardial perforations in the area of the anticipated infarction made with a carbon dioxide laser. Twelve animals served as controls. Hemodynamic measurements and transdiaphragmatic quantitative echocardiograms were obtained before, immediately after, and 2, 5, and 8 weeks after infarction. Eighteen sheep completed the protocol. Results: All animals had large anteroapical left ventricular aneurysms with massive ventricular enlargement. Immediately after infarction the anterior wall became thinner and dyskinetic in all sheep. At 8 weeks aneurysmal size and shape were indistinguishable between groups. Two days after infarction, laser holes were filled with fibrin. At 5 and 8 weeks the infarct consisted of dense collagen, fibroblasts, scattered calcifications, myocyte fragments, neutrophils, macrophages, and no laser holes. There were no significant differences at any time between groups for cardiac pressures or output, ventricular volumes, ejection fraction, stroke work, and the stroke work–left ventricular end-diastolic pressure index. Conclusion: Transmyocardial laser perforations do not revascularize acute myocardial infarction in sheep. (J Thorac Cardiovasc Surg 1998;116:752-62

Successful Coronary Artery Bypass Operation in a SARS-COV-2 Infected Patient with Acute Coronary Syndrome

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is overwhelming healthcare resources and infrastructure worldwide. Earlier reports have demonstrated complicated postoperative courses and high fatality rates in patients undergoing emergent cardiothoracic surgery who were diagnosed postoperatively with COVID-19. These reports raise the possibility that active COVID-19 might precipitate a catastrophic pathophysiological response to infection in the postoperative period and lead to unfavorable surgical outcomes. Hence, it is imperative to screen patients with SARS-CoV-2 infection before surgery and to carefully monitor them in the postoperative period to identify any signs of active COVID-19. In this report, we present the successful outcome of coronary artery bypass grafting (CABG) operation in a patient with asymptomatic SARS-CoV-2 infection presenting with an acute coronary syndrome and requiring urgent surgical intervention. We employed a thorough strategy to identify subclinical COVID-19 disease, and after confirming the absence of active disease, proceeded with the CABG operation. The patient outcome was successful with the absence of any overt COVID-19 manifestations in the postoperative period

Safe Technique of Coronary Button Preparation in Redo Bentall Operation

We introduce a technique of coronary button reconstruction in performing a redo Bentall procedure. A coronary button is prepared leaving a 3 to 4 mm rim of old Dacron graft surrounding the previous button. The Dacron rim may be sewn to the new aortic root graft directly or via an interposed 8- or 10-mm graft, using a modified Cabrol technique. If the button is comprised of good tissue and can be well-mobilized, it is removed from the Dacron rim and anastomosed directly to the new Dacron graft

Anesthetic Management of Combined Heart-Liver Transplantation in a Patient with Ischemic Cardiomyopathy and Cardiac Cirrhosis: Lessons Learned

COMBINED HEART-LIVER transplantation (CHLT) in carefully selected patients has resulted in acceptable outcomes since its introduction by Starzl in 1984.1 The procedure, however, remains relatively uncommon, with 188 cases performed in the United States to date.2 CHLT recipients range from patients with dual-organ pathology, such as amyloidosis, metabolic diseases, or alcoholism, to patients with primary end-stage liver cirrhosis associated with severe cardiomyopathy, to others with terminal right-sided heart failure (HF) resulting in liver cirrhosis. HF resulting in cardiac cirrhosis represents one of the least frequent indications for CHLT,3 in part due to ongoing advances in the treatment of heart disease; nonetheless, its true prevalence in the general population is difficult to assess as it commonly is subclinical. The latter patient population presents a unique set of pathophysiologic considerations with inherent challenges pertaining to perioperative management, as will be detailed in this case study. The patient presented has provided written consent for consultation of his medical records for the purpose of this repor