Vascular calcifications in homozygote familial hypercholesterolemia.

BACKGROUND: Patients with homozygous familial hypercholesterolemia (hmzFH) attributable to LDL receptor gene mutations have shown a remarkable increase in survival over the last 20 years. Early onset coronary heart disease (CHD) and calcific aortic valve stenosis are the major complications of this disorder. We now report extensive premature calcification of the aorta in patients with hmzFH. METHODS AND RESULTS: We examined 25 hmzFH patients from Canada; mean age was 32 years (range 5 to 54), and mean baseline cholesterol before treatment was 19+/-5 mmol/L (737+/-206 mg/dL). Aortic calcification was quantified using computed tomography (CT). An elevated mean calcium score was found in patients by age 20 and correlated with age (r(2)=0.53, P=0.001). One quarter (24%) of patients underwent aortic valve surgery. CONCLUSIONS: We document premature severe aortic calcifications in all adult hmzFH patients studied. These presented considerable surgical management challenges. Strategies to identify and monitor aortic calcification in hmzFH by noninvasive techniques are required, as are clinical trials to determine whether additional or more intensive therapies will prevent the progression of such calcifications. Whether vascular calcifications in hmzFH subjects are related to sustained increases in LDL-C levels or to other mechanisms, such as abnormal osteoblast activity, remains to be determined.

Clinical benefit of neoral dose monitoring with cyclosporine 2-hr post-dose levels compared with trough levels in stable heart transplant patients.

BACKGROUND: Based on the excellent correlation between cyclosporine A 2-hr postdose blood levels (C2) and the area under the concentration versus time curve, we evaluated the clinical benefit of Neoral dose monitoring with C2 compared trough levels (C0) in stable heart transplant patients. METHODS: We studied 114 stable adult patients followed at the heart transplant clinic, who were >1 year after surgery. In May 1996 (period 1, follow-up 10+/-4 months), Neoral dose monitoring was based on C2 (300-600 ng/ml); while in May 1997 (period 2, follow-up 10+/-2 months), it was based on C0 (100-200 ng/ml). Cyclosporine A levels were measured by an enzyme multiplied immunologic technique. Clinical benefit was defined by the absence of acute rejection, no mortality, no fall in left ventricular ejection fraction >10%, and no increase in serum creatinine >10% (compared with baseline). RESULTS: During period 1, Neoral dose, cyclosporine A, C0 and C2, and serum creatinine, decreased by 26, 56, 45, and 2.3%, respectively. At the end of period 2, the same variables increased by 24, 56, 38, and 10%, respectively (P<0.0001). The incidence of acute rejection was similar (period 1: 0.87%, period 2: 0.96%). The left ventricular ejection fraction (initial/final) remained stable (period 1: 57+/-91%/58+/-13%, period 2: 59+/-11d/58+/-10%). Mortality did not differ (period 1: 7.9%, period 2: 9.6%). A clinical benefit was observed in 69.3% of the patients during period 1 vs. 43.3% of the patients during period 2 (P<0.00001). CONCLUSIONS: In stable heart transplant patients, a greater clinical benefit was observed when Neoral dose monitoring was performed according to C2, compared with C0.

Impact of transfusion of mediastinal shed blood on serum levels of cardiac enzymes.

BACKGROUND: Infusion of shed mediastinal blood using an autotransfusion system is a widely applied technique of blood conservation in cardiac surgery. Serial determinations of serum creatine kinase (CK), its MB isoenzyme (CK-MB), and lactate hydrogenase (LDH) levels have been used to monitor perioperative myocardial injury. We investigated the impact of postoperative autotransfused blood infusion on serum levels of these enzymes. METHODS: We performed a retrospective analysis of postoperative serum CK, CK-MB, and LDH levels of 300 patients who had elective uncomplicated aortocoronary bypass grafting. Shed mediastinal blood samples from 26 patients were analyzed for CK, CK-MB (enzymatic activity and mass), and LDH levels before infusion. RESULTS: High postoperative serum levels of CK and LDH were observed after infusion of autotransfused blood. Shed mediastinal blood contained extremely high levels of these enzymes, particularly from patients who had internal mammary artery dissection. There was a strong correlation (r = 0.96) between measured CK-MB enzyme activities and those calculated from the CK-MB mass units. CONCLUSIONS: Infusion of autotransfused blood containing high concentrations of CK and LDH results in elevated serum levels of these enzymes. Hemolysis, frequently present in shed blood, does not interfere with the routine biochemical assays for CK and CK-MB enzyme activities. Caution should be taken when postoperative cardiac enzyme levels are used to determine myocardial injury after aortocoronary bypass grafting if autotransfusion is used as a method of blood conservation.

Impact of preoperative left ventricular ejection fraction on postoperative left ventricular remodeling after mitral valve repair for degenerative disease.

BACKGROUND AND AIM OF THE STUDY: Mitral valve repair has been associated with better preservation of left ventricular (LV) function, especially in the setting of degenerative regurgitation. The goal of this study was to evaluate the impact of mitral valve repair on postoperative LV ejection fraction (LVEF) and LV remodeling as determined by LV end-systolic and diastolic diameters. METHODS: A prospective echocardiographic and clinical evaluation of 91 patients undergoing mitral valve repair for degenerative regurgitation between 1993 and 1998 was performed. Patients with normal preoperative LVEF (> or = 50%; group 1, n = 71) were compared with patients with decreased preoperative LVEF (< 50%; group 2, n = 20) one year after mitral valve repair. RESULTS: In group 1 patients, the LVEF was preserved at one year, while the LV end-systolic diameter was significantly reduced from 36 +/- 7 mm to 32 +/- 8 mm (p <0.05). There was a significant improvement in LVEF in group 2 patients (38 +/- 6% preoperative versus 50 +/- 12% at one year, p <0.05). The preoperative LV end-systolic diameter was significantly larger in group 2 patients (47 +/- 9 mm) than in group 1 patients (36 +/- 7 mm) (p <0.001), but decreased to normal values at one year after repair (38 +/- 7 mm, p <0.05). CONCLUSION: There was good preservation of LV function after mitral valve repair in group 1 patients. The LVEF significantly increased towards normal in patients with depressed LV function before repair. The LV systolic diameter was restored to normal within one year of repair, even in patients with poor LV function. Decreased preoperative LV function should not be a contraindication to mitral valve repair in patients with degenerative regurgitation.

Churg-Strauss syndrome presenting with marked eosinophilia and pericardial effusion.

The Churg-Strauss syndrome is a rare but treatable clinical entity. Its clinical presentation is thought to be stereotypic but is not. The authors report the first instance of a patient with the Churg-Strauss syndrome with hemodynamically significant pericardial effusion but without concurrent active pulmonary, renal or neurological involvement. Pericardial biopsy was the key to diagnosis and, therefore, therapy.

Transplantation versus coronary artery bypass in patients with severe ventricular dysfunction. Surgical outcome and quality of life.

BACKGROUND: The purpose of this study is to evaluate the quality of life, functional status and survival rate of patients with left ventricular ejection fraction (LVEF) < or = 20% following coronary bypass (CABG) versus heart transplantation. EXPERIMENTAL DESIGN: comparative study, mean follow-up of 20 months. SETTING: division of cardiac surgery at a McGill University-based hospital in Montreal, Canada. PATIENTS: the charts of 65 consecutive patients with angiographic LVEF < or = 20% were reviewed. Among these patients, 14/65 were referred for transplantation but instead underwent CABG (Group I) after consultation with the transplant committee. The charts of 14 matched transplant patients (Group II) were reviewed. The SF-36 and Duke's questionnaire forms were mailed to both groups in order to evaluate their quality of life and functional capacity, respectively. INTERVENTIONS: comparison between coronary bypass and heart transplantation. MEASURES: main outcome measures were mortality, quality of life, and functional capacity. RESULTS: Results are expressed as mean+/-SEM. The in-hospital mortality rate of CABG among all patients with LVEF < or = 20% was 4.6% (3/65). Among the 14 CABG patients initially referred for transplantation, perioperative mortality was 1/14 (7.1%), same as in the matched transplant group. Three additional group I patients were reported by family to have died of cardiac events at follow-up period. Postoperative death identified at follow-up was assigned the lowest life quality score. The transformed quality of life scores were as follows: physical functioning: I=42.5+/-10.6, II=73.2+/-7.2, p=0.029; physical role: I=35.0+/-13.5, I=61.4+/-13.2, p=0.180; bodily pain: I=54.0+/-14.0, II=69.8+/-8.5, p=0.349; general health: I=34.7+/-9.2, II=84.6+/-5.2, p=0.0003; vitality: I=36.5+/-9.3, II=60.0+/-5.2, p=0.045; social functioning: I=55.0+/-4.0, II=87.5+/-5.1, p=0.050; emotional role: I=36.7+/-15.3, II=87.9+/-6.8, p=0.009; mental health: I=52.8+/-12.4, II=81.5+/-4.2, p=0.054. Duke's activity status index: I=16.8+/-4.2, II=31.8+/-4.2, p=0.021. CONCLUSIONS: Heart transplant is associated with a significantly superior postoperative quality of life and functional capacity than bypass surgery. However, in patients with LVEF < or = 20%, CABG can be performed with an acceptable perioperative mortality of 4.6%-7.1%, similar to the rate for transplantation.

Clinical death and the measurement of stressed vascular volume.

OBJECTIVES: To measure stressed vascular volume in humans and to review the concepts of stressed and unstressed vascular volume. DESIGN: Observational study during surgical procedure. SETTING: Operating room at a university hospital. PATIENTS: Five patients undergoing hypothermic circulatory arrest for surgery on major vessels. INTERVENTION: We measured the volume that drained from the patient to the reservoir of the pump when the pump was turned off. MEASUREMENTS AND MAIN RESULTS: Stressed volume was 20.2+/-1.0 mL/kg, which is 30% of the predicted blood volume of these patients. CONCLUSION: The amount of blood volume that determines vascular filling pressure is only about a quarter of the total predicted volume, which means that there is a large reserve of unstressed volume that can be recruited to maintain vascular filling pressure.

Intraoperative duplex study of internal thoracic artery spasm during coronary bypass.

In this article, we document flow disturbance due to internal thoracic artery spasm (ITA) in a patient undergoing minimally invasive coronary artery grafting. We used intraoperative duplex scanning. Application of systemic vasodilators resulted in rapid improvement of ITA flow, as demonstrated by serial duplex examinations.

Reinfusion of mediastinal blood in CABG patients: impact on homologous transfusions and rate of re-exploration.

BACKGROUND: Reinfusion of mediastinal shed blood after cardiac surgery has been used in some centers to reduce exposure to homologous blood transfusions. The method has not been widely applied mostly because some studies have failed to demonstrate a significant benefit. METHODS: A group of 675 consecutive patients undergoing first-time, isolated coronary artery bypass surgery (CABG) was studied. Prospective data was collected on the first 375 patients receiving autotransfusion (ATS) of mediastinal shed blood. The charts of 338 patients immediately preceding the institution of the ATS program at our institution (NO ATS group) were retrospectively reviewed. Transfusion of homologous blood products and rate of re-exploration for bleeding were closely monitored. RESULTS: The two groups were identical. The net blood loss was significantly less in the ATS group than in the NO ATS group (1013 +/- 431 cc vs 1371 +/- 631 cc, p < 0.0001). Rate of exploration for postoperative bleeding was 1.5% in the ATS group and 5.0% in the NO ATS group (p < 0.01). In the ATS group, 51.9% of patients were not exposed to any homologous blood product (vs 17.8% in the NO ATS group, p < 0.0001). The ATS patients received on the average 2.9 +/- 7.2 units of blood products versus 6.4 +/- 9.7 units in the NO ATS group (p < 0.0001). CONCLUSION: Reinfusion of mediastinal shed blood significantly reduces exposure to homologous blood transfusions and rate of reexploration. The ATS system reduces the number of re-explorations for coagulopathy-related postoperative hemorrhage.

Chest wall infarction following bilateral internal mammary to coronary arterial bypass in a patient with a thoracoabdominal aneurysm.

A 69-year-old man with severe peripheral vascular disease and a known thoracoabdominal aortic aneurysm underwent bilateral internal mammary artery (BIMA) to coronary artery bypass grafting and aortic hemiarch replacement. He immediately thereafter developed massive chest wall ischemia and infarction with a severe metabolic acidosis, and subsequently died. Chest wall infarction following BIMA harvesting has not been previously described. Cautious use of internal mammary arterial grafting may be in order in the severe vasculopath with significant thrombo-occlusive thoracoabdominal aortic disease.

Sternotomy after muscle flap repair of sternal osteomyelitis and mediastinitis.

A 61-year-old man who had undergone aortocoronary bypass developed sternal osteomyelitis and mediastinitis which required sternal debridement and muscle flap interposition. Two years later the midline incision was used for an orthotopic heart transplantation. No major technical difficulties were encountered at the time of transplantation.

Enhanced 24-hour in vitro heart preservation with adenosine and adenosine monophosphate.

Continuous hypothermic perfusion is an effective means of preserving ex vivo cardiac allografts. Using canine hearts, we assessed the ability of the high-energy phosphate precursors adenosine and adenosine monophosphate to enhance the protective effect of continuous hypothermic perfusion. Group 1 hearts (controls) were perfused for 24 hours with a modified Krebs-Henseleit solution. Group 2 hearts were perfused with control perfusate to which adenosine was added (20 mumol/L). Group 3 hearts were perfused with control perfusate with adenosine monophosphate (0.1 mmol/L). After perfusion heart weights increased similarly in all groups. Coronary vascular resistance increased during the preservation period in group 1 hearts, but decreased in groups 2 and 3 hearts. Developed pressures were 103 +/- 22 mm Hg in group 1, 163 +/- 27 mm Hg in group 2 (p less than 0.01), and 141 +/- 34 mm Hg (p less than 0.05) in group 3. The rate of pressure development in group 2 (2143 +/- 249 mm Hg) and group 3 (2059 +/- 395 mm Hg) hearts was significantly greater than in group 1 hearts (1434 +/- 363 mm Hg, p less than 0.01). Only group 3 myocardial adenosine triphosphate levels were significantly greater than controls (3.18 +/- 0.52 mumol/gm vs 2.12 +/- 0.74 mumol/gm, p less than 0.05) on completion of perfusion. Myocardial lactate levels at this time were significantly higher in group 1 hearts (7.48 +/- 3.96 mumol/gm) compared with groups 2 and 3 (0.34 +/- 0.58 mumol/gm and 1.50 +/- 0.91 mumol/gm, respectively, p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Contemporary operative management of pulmonary metastases of colorectal origin.

The management of patients with metastatic disease from primary carcinoma of the colon and rectum is still controversial. To evaluate the results of resection of pulmonary metastases from patients with colorectal primaries, a retrospective study of all patients who underwent such resection was carried out at the teaching hospitals of McGill University and Université de Montréal. A total of 345 patients admitted with pulmonary metastases; 27 of them underwent pulmonary resection with the extent of the resection varying from wedge excision of the metastatic nodule to pneumonectomy. In 25 of the 27 patients the resection was considered curative. Eight of the 27 patients had resection of two metastatic lesions while the remaining 19 patients had resection of solitary lesions. The interval between resection of the primary colorectal malignancy and the resection of the metastatic lesion (disease-free interval) varied from 2 to 77 months with a median interval of 35 months. The five-year survival following resection of pulmonary metastases was 21 percent. A prolonged interval between treatment of the primary and resection of the pulmonary metastasis was associated with a longer survival. This retrospective study demonstrates that prolonged survival can be achieved following resection of pulmonary metastases from colorectal carcinoma.

Anesthesia for deep hypothermic circulatory arrest in adults: experience with the first 50 patients.

OBJECTIVE: To evaluate the efficacy of a simple method of central nervous system (CNS) protection in patients undergoing deep hypothermic circulatory arrest (DHCA) lasting less than 30 minutes, for a variety of complex cardiovascular procedures. DESIGN: A retrospective case review. SETTING: A university teaching hospital. PARTICIPANTS: Fifty consecutive patients (25 women, 25 men) undergoing elective or emergency cardiovascular operations requiring DHCA between August 1991 and December 1996. INTERVENTIONS: Patients underwent DHCA for a variety of surgical procedures. Neurologic protection was with thiopental, ice packs to the head, and systemic core hypothermia to a nasopharyngeal temperature (NPT) of 18 degrees to 20 degrees C. MEASUREMENTS AND MAIN RESULTS: The mean duration of circulatory arrest was 18 +/- 10 minutes (range, 5 to 42 minutes). The mean NPT at time of arrest was 18.7 degrees +/- 1.7 degrees C. Three patients (6%) had gross CNS morbidity, one of whom died. The circulatory arrest times for these three patients were 8, 39, and 40 minutes. Perioperative mortality was 8% (n = 4). The circulatory arrest times for the patients who died were 12, 13, 23, and 39 minutes. CONCLUSION: The anesthetic management of DHCA described is simple, effective, and safe, and can be performed in any institution that performs cardiac surgery.

Pentastarch versus albumin in cardiopulmonary bypass prime: impact on blood loss.

BACKGROUND: Albumin is commonly used as a volume expander in cardiopulmonary bypass (CPB) prime. Pentastarch, a low molecular weight hetastarch, may provide similar efficacy at decreased cost but is known to alter coagulation profiles. Infectious concerns forced the temporary withdrawal of albumin in our institution. Therefore we evaluated pentastarch as an alternative with regards to perioperative hemostasis and blood loss. METHODS: One hundred consecutive adult patients undergoing first-time aorto-coronary bypass were given 750 mL of 10% pentastarch (represented as P in calculations) diluted in 1000 mL of Ringer's solution added in their CPB prime. A similar control group of 100 consecutive patients had received 200 mL of 25% albumin (represented as A in calculations) diluted in 1500 mL of Ringer's solution. RESULTS: Postoperative prothrombin time (PT) was slightly higher with pentastarch (P: 14.9 +/- 1.5 seconds, A: 14.2 +/- 1.3 seconds, p = 0.003). Postoperative bleeding was also increased (P: 2337 +/- 1242 mL, A: 1981 +/- 1121 mL, p = 0.034), mostly because of recirculated shed mediastinal blood (P: 834 +/- 499 mL, A: 640 +/- 388, p = 0.002) rather than lost pleural tube blood (P: 1503 +/- 821 mL, A: 1341 +/- 824 mL, p = 0.16). Overall net blood loss (P: 2014 +/- 914 mL, A: 2061 +/- 1015, p = 0.73) was similar. Blood-product transfusion requirements and postoperative daily hematocrits did not differ. CONCLUSION: The diminished coagulability associated with this dose of pentastarch resulted in increased postoperative bleeding. However, with recirculation of shed mediastinal blood, there was no net increase in blood loss. In this setting, pentastarch may serve as a suitable alternative to albumin.