Do triglyceride and low-density lipoprotein blood levels affect the vascular response to cyclosporine?
Explore the source record for details and available documents.
Acetylcholine↗
Biomedical subjects
L C Pelletier
Publications and source records attributed to L C Pelletier.
Effect of pentoxifylline on renal toxicity of cyclosporine: preliminary results.
Explore the source record for details and available documents.
Analysis of Variance↗
Myocardial distribution of retrograde cardioplegic solution assessed by myocardial thallium 201 uptake.
Perfusion of the right ventricular myocardium with retrograde infusion of cardioplegic solution through the coronary sinus has been reported to be less than optimal. To study left and right ventricular perfusion during retrograde and antegrade coronary sinus cardioplegia, we added 0.5 mCi of thallium 201 to 500 ml of hyperkaliemic crystalloid cardioplegic solution injected retrogradely into the coronary sinus at low perfusion pressure (20 to 40 mm Hg) in 14 dogs and antegradely in the ascending aorta in seven dogs. The cardioplegic solution was cold (4 degrees C) in eight animals perfused retrogradely and warm (21 degrees C) in 13 animals. After aortic crossclamping, the ascending aorta and the left and right ventricles were vented and cardioplegic solution was injected retrogradely into the coronary sinus. Antegrade injections were performed after aortic crossclamping and venting of the left and right ventricles and of the left and right atrium. After cardioplegic arrest, the heart was harvested, fixed, and scanned with a gamma camera. With cold retrograde cardioplegia, 82% +/- 5% of the injected thallium 201 activity was identified in the myocardium--71% +/- 9% for warm retrograde perfusion and 80% +/- 3% for antegrade perfusion (p > 0.05). Focal areas of hypoactivity in the septum and in the right ventricular free wall were present at scintigraphic imaging in all animals receiving retrograde perfusion. In conclusion, most thallium 201 activity of cardioplegic solution injected retrogradely in the coronary sinus was identified in the myocardium, but focal areas of hypoactivity in the septum and in the right ventricular free wall were present, indicating uneven distribution. Temperature of the crystalloid solution had no effect on the myocardial distribution of the thallium 201 radiotracer in the myocardium.
Animals↗
Mediastinal and pericardial complications after heart transplantation. Not-so-unusual postoperative problems?
Of a total of 133 patients who underwent heart transplantation, 16(12%) had pericardial and mediastinal complications. Non-infectious pericardial complications, pericardial effusion and constriction were noted in ten patients, and infectious pericarditis or mediastinitis in six. Cardiac echocardiography, catheterization and magnetic resonance imaging were useful in assessing these problems. All patients underwent surgical treatment, pericardial drainage, pericardectomy or muscle flap closure. Twelve (75%) of these 16 patients are long-term survivors. In conclusion, pericardial and mediastinal complications are common after heart transplantation, and aggressive surgical treatment is most often effective in their control.
Adult↗
Outcome of rationing access to open-heart surgery: effect of the wait for elective surgery on patient outcome.
OBJECTIVE: To assess the effect of the waiting period before elective open-heart surgery on patient outcomes. DESIGN: Retrospective analysis. SETTING: The Montreal Heart Institute, a referral centre in cardiology and cardiac surgery. PATIENTS: All 568 patients who underwent open-heart surgery on an elective basis or following urgent admission or interhospital transfer between October 1991 and February 1992. MAIN OUTCOME MEASURES: In-hospital death rate, incidence of postoperative complications, length of stay in the intensive care unit (ICU) and total length of hospital stay. RESULTS: A total of 206 patients (151 men and 55 women with an average age of 59.0 [standard error of the mean (SEM) 1] years) underwent elective surgery, and 362 patients (264 men and 98 women with an average age of 62.0 [SEM 1] years) underwent urgent surgery. The mean wait for elective surgery was 2.8 (SEM 0.2) months. There was no significant difference between the two groups in the in-hospital death rate (4% v. 4%), the average length of stay in the ICU (4.4 [SEM 0.2] days v. 5.8 [SEM 1] days) or the average total length of hospital stay (9.0 [SEM 0.4] days v. 9.1 [SEM 1] days). As would be expected, postoperative complications developed in significantly more patients in the urgent group (27%) than the elective group (18%) (p = 0.02). Eight patients were admitted on an urgent basis for surgery owing to worsening symptoms or acute myocardial infarction after a mean wait of 4.6 months. One patient died suddenly at home 1 month after medical investigation while awaiting repeat coronary artery bypass grafting. Among the 206 patients who underwent elective surgery there was no relation between waiting time and adverse clinical outcomes after surgery. CONCLUSIONS: The results suggest that the wait before elective open-heart surgery had no effect on patient outcome after surgery in our institution. A policy of a short waiting period before elective open-heart surgery for patients whose condition is stable is safe and acceptable only if rapid access to medical and surgical treatment is available should it become necessary.
Analysis of Variance↗
Effects of pressure and duration of hyperkalemic infusions on endothelial function.
Infusions of crystalloid hyperkalemic cardioplegic solutions (CHCSs) are known to impair endothelium-dependent coronary relaxation. This impairment might also be influenced by high perfusion pressure and duration of CHCS infusion. To verify this hypothesis, we designed experiments to study the influence of pressure and duration of CHCS infusion as modulating factors in CHCS-related endothelial impairment. Isolated hearts of Sprague-Dawley rats were studied in a Langendorff apparatus for coronary endothelial function. Hearts (n = 6) were exposed to four different CHCSs containing 12, 24, 40, or 100 mmol/L of potassium chloride (KCl). Endothelial and smooth muscle functions were respectively tested by infusion of 5-hydroxytryptamine (1 x 10(-6) mol/L) and sodium nitroprusside (1 x 10(-5) mol/L) before and after CHCS perfusion. In group I (n = 24), 37 degrees C CHCSs were perfused at 80 cm H2O of pressure for 30 minutes. In group II (n = 24), the same CHCSs were perfused at 160 cm H2O for 30 minutes. In group III (n = 18), CHCSs containing 24, 40, and 100 mmol/L of KCl were infused at 160 cm H2O for 10 minutes. In all groups, response to sodium nitroprusside was unaltered by CHCS infusion, indicating that smooth muscle function was preserved. However, in group II, 5-hydroxytryptamine-induced vasodilation was significantly impaired in hearts perfused with CHCS containing 24 mmol/L of KCl or more, suggesting endothelial damage. This study demonstrates that, in addition to KCl concentration, pressure and duration of infusion are two major determinants in CHCS-mediated endothelial damage.
Animals↗
1992: Effect of internal mammary artery dissection on sternal vascularization. 1993 update.
Explore the source record for details and available documents.
Arteries↗
Transluminal angioplasty of the subclavian artery in patients with internal mammary grafts.
From January 1987 to January 1992, 11 patients underwent percutaneous transluminal angioplasty (PTA) for the treatment of subclavian artery stenosis before or after coronary artery bypass grafting (CABG) using the internal mammary artery (IMA). There were 8 men and 3 women, with a mean age of 57 +/- 7 years. Four patients had PTA 1 to 4 months before undergoing CABG with IMA grafts, because of either asymptomatic supraclavicular murmurs or neurologic symptoms. Seven patients underwent PTA 2 to 37 months after CABG with IMA grafts, because of recurrent angina. Subclavian artery stenosis was on the left side in 9 patients, the right side in 1 patient, and bilateral in 1 patient. Ten PTA procedures were successful in 9 patients. All patients with post-CABG angina had reversal of the ischemia. There were three complications: one femoral artery thrombosis, one brachial plexus hematoma after an axillary approach, and one acute pulmonary edema after the procedure. Follow-up after PTA ranged from 1 to 60 months (mean, 38 +/- 17 months). Nine patients had no angina at follow-up and 2 had stable angina (class II) upon exertion. Upper-limb Doppler studies showed no evidence of restenosis in any of these patients at a mean follow-up of 38 months. Subclavian artery PTA is a useful alternative to IMA bypass grafting in patients with subclavian artery stenosis discovered preoperatively, and it is the treatment of choice for those presenting with post-CABG angina due to subclavian artery stenosis proximal to an IMA graft.
Adult↗
Clinical experience with the right gastroepiploic artery in coronary artery bypass grafting.
The excellent long-term results with the internal mammary artery for coronary artery bypass grafting have prompted the search for other conduits with similar characteristics. From December 1989 to December 1991, the right gastroepiploic artery (RGEA) has been used as an in situ graft to the posterior descending coronary artery in 51 patients at the Montreal Heart Institute. The patients' age averaged 50 +/- 11 years. Three-vessel coronary artery disease was present in 41 patients and two-vessel disease in the remaining 10 patients. In all but 1 patient, bilateral internal mammary artery grafting was performed in addition to RGEA grafting. The number of grafts per patient averaged 3.2 +/- 0.8. There was no operative mortality. Morbidity was minimal with only myocardial infarction and a pleural effusion in 1 patient. In 1 patient, a splenectomy had to be performed because of iatrogenic tear during dissection of the RGEA. The average hospital stay was 8.2 +/- 2.6 days. Enteral nutrition was resumed on average 2 days after operation. Angiographic evaluation of RGEA grafts was performed before discharge or within the first month after surgery in 31 patients. In 28 patients (28/31, 90%) the RGEA graft was patent, two grafts were occluded, and in the remaining patient, the graft could not be visualized due to technical difficulties during angiography. A second angiographic evaluation was performed in 5 patients, 1 year after operation. Four RGEAs were patent and 1 was occluded. Clinical follow-up averaged 4 months (range 1 to 15 months).(ABSTRACT TRUNCATED AT 250 WORDS)
Adult↗
The role of preservation solutions in coronary endothelial damage during cold storage.
The effects of cold storage and type of preservation solution on coronary endothelial function are not well understood. Experiments were designed to evaluate coronary endothelial-dependent relaxation after a 4-hr cold (4 degrees C) storage in different preservation solutions. Isolated rat hearts were studied in the Langendorff apparatus for coronary endothelial function. After 30 min of stabilization, hearts were arrested with a 10-min perfusion of 4 degrees C crystalloid hyperkalemic cardioplegic solution (CHCS) containing 24 mmol/L of KCl and stored for 4 hr in the following preservation solutions: CHCS, Krebs-Ringer's solution (KR), 0.9% NaCl (NS), and University of Wisconsin solution (UW). A fifth group was perfused and stored in UW solution. Endothelial-dependent and independent coronary artery vasorelaxation were tested, respectively, by infusing 5-hydroxytryptamine (5-HT) (1 x 10(-6) mol/L) and sodium nitroprusside (SNP) (1 x 10(-5) mol/L) before and 30 min after the storage period. In hearts stored in CHCS and KR, the coronary artery flow increase to 5-HT and SNP infusion were not significantly affected. However, in hearts preserved with NS and UW solutions, 5-HT coronary response was significantly decreased, indicating endothelial dysfunction. In addition to these findings, coronary flow increase to SNP infusion was decreased in the group perfused and stored with UW, suggesting smooth muscle damage. These experiments suggest that 4-hr cold storage in NS or UW impairs endothelial-dependent coronary relaxation in the isolated rat heart model.
Adenosine↗
[Results of percutaneous dilatation of subclavian artery stenosis in patients with internal mammary grafts].
From January 1987 to January 1992, 11 patients underwent percutaneous transluminal angioplasty (PTA) for subclavian artery (SCA) stenosis before or after coronary artery bypass grafting (CABG) with the internal mammary artery (IMA). There were 8 men and 3 women with a mean age of 57 +/- 7 years. Four patients had PTA 1 to 4 months before undergoing CABG with IMA grafts, because of asymptomatic subclavian murmurs or of neurologic symptoms. Seven patients underwent PTA 2 to 37 months after CABG with IMA grafts, because of recurrent angina. Subclavian artery stenosis was present on the left side in 9 patients, the right side in one patient, and was bilateral in one patient. Ten PTA procedures were successful in 9 patients. All patients with post-CABG angina had reversal of the ischemia. Three complications occurred: 1 femoral artery thrombosis, 1 branchial plexus hematoma after an axillary approach, and 1 acute pulmonary edema after the procedure. Follow-up ranged from 1 to 60 months after PTA (mean 38 +/- 17 months). Nine patients had no angina at follow-up and 2 presented with stable angina (class II) upon exertion. Upper-limb Doppler studies showed no evidence of restenosis in all of these patients, at a mean follow-up of 38 months. Subclavian artery percutaneous transluminal angioplasty is a useful alternative for candidates to IMA bypass grafting with SCA stenosis discovered pre-operatively, and it is the treatment of choice for those presenting with post-CABG angina due to SCA stenosis proximal to an IMA graft.
Angioplasty, Balloon↗
[Effect of different solutions of preservatives on the endothelial function of coronary arteries in rats].
The effects of cold storage and type of preservation solution on coronary endothelial function are not well established. Experiments were designed to evaluate coronary endothelial-dependent relaxation after a 4-hour cold (4 degrees C) storage in different preservation solutions. Rat hearts, mounted in the Langendorff apparatus, were arrested with a 10-minute perfusion of 4 degrees C crystalloid hyperkaliemic cardioplegic solution (CHCS) (KCl 24 mEq/l) and stored for 4 hours in the following preservation solutions: CHCS (n = 6), Krebs-Ringer solution (KR) (n = 6), 0.9% NaCl (NS) (n = 6) and the University of Wisconsin solution (UW) (n = 6). A fifth group (n = 6) was perfused and stored in UW solution. Endothelium-dependent and independent coronary artery vasorelaxations were respectively tested by infusing 5-hydroxytryptamine (5-HT) (10(-6) mol/l) and sodium nitroprusside (SNP) (10(-5) mol/l) before and after the storage period. In hearts stored with CHCS or KR, coronary artery flow increase to 5-HT and SNP infusions were not significantly affected. However, in hearts preserved with NS or UW solutions, 5-HT coronary response was significantly decreased, indicating endothelial dysfunction. In addition to these findings, coronary flow increase to SNP infusion was decreased in the group perfused and stored with UW, suggesting smooth muscle dysfunction. These experiments suggest that 4-hour cold storage in NS or UW impairs endothelial-dependent coronary relaxation in the isolated rat heart model.
Adenosine↗
[Place of gastroepiploic and epigastric arteries in myocardial revascularization].
Seventy patients underwent coronary artery bypass grafting with the right gastroepiploic artery or the inferior epigastric artery between 1989 and 1992 at the Montreal Heart Institute. There were 68 men and 2 women with a mean age of 53 +/- 8 years, the right gastroepiploic artery in situ was anastomosed to the right coronary artery in 55 patients and the inferior epigastric artery (free graft) was used in 18 patients. Double internal thoracic artery grafts were used in all patients. Early patency rate of right gastroepiploic artery and inferior epigastric artery grafts was 91% (31/34 grafts) and 57% (8/14 grafts) respectively. One patient died after surgery (1.4%) from acute renal failure and one patient developed an acute myocardial infarction (1.4%) at surgery. Fifty-five patients (55/57, 96%) showed no evidence of angina at the last follow-up. In conclusion, patency rate and clinical results of coronary artery bypass grafting with the right gastroepiploic artery graft were excellent and patency rate of inferior epigastric artery graft was unsatisfactory. We suggest that epigastric artery grafts should be used with caution, only when no other alternative is available.
Abdomen↗
Early experience with the inferior epigastric artery in coronary artery bypass grafting. A word of caution.
The excellent results with the internal thoracic artery for coronary artery bypass grafting have prompted the search for other arterial conduits. From November 1991 to February 1992, 18 patients underwent coronary artery bypass grafting with the use of inferior epigastric artery grafts. Patients' ages averaged 52 +/- 9 years. Bilateral internal thoracic artery grafts were used in 17 patients (17/18, 94%) and a free graft with one inferior epigastric artery was used in each patient. The inferior epigastric artery grafts were anastomosed to the right coronary artery (n = 9), a marginal circumflex artery (n = 4), and to a diagonal artery (n = 5). Three patients had abdominal wound complication related to harvesting of the inferior epigastric artery. Immediate postoperative angiographic evaluation of inferior epigastric artery grafts showed that eight grafts were patent (8/14, 57%). Four of the occluded inferior epigastric arteries were grafted to the right coronary artery and one to the second marginal circumflex coronary artery. Because of the low patency rate of inferior epigastric artery grafts, a word of caution is necessary in the selection of patients. At the present time, the inferior epigastric artery appears to be an interesting alternative only in patients who have no other available conduits.
Adult↗
Blockade of cyclosporine-induced vasoconstriction by the calcium channel blocker diltiazem in dogs.
The calcium channel blocker diltiazem has been shown to reduce cyclosporine toxicity both in clinical and in experimental studies. To determine the effect of diltiazem administration on cyclosporine vasoconstriction and on renal release of endothelin, we administered cyclosporine in models of renal and hind limb autoperfusion in the dog. Infusion of cyclosporine in the hind limb (20 mg) during diltiazem perfusion caused an average increase of 6 +/- 2 mm Hg in hind limb perfusion pressure compared with 17 +/- 2 mm Hg before diltiazem, a significant difference (p < 0.05). Similarly, injections of cyclosporine (10 mg) in the kidney during diltiazem infusion caused an average increase of 26 +/- 4 mm Hg in renal perfusion pressure compared with 83 +/- 13 mm Hg before diltiazem infusion, a significant decrease in the renal vascular response (p < 0.05). On the other hand, sodium nitroprusside did not change the renal vasoconstriction to cyclosporine, which suggests a specific effect of diltiazem. Serum levels of endothelin in renal venous blood increased from 0.5 +/- 0.4 pg/ml to 3.8 +/- 0.6 pg/ml with cyclosporine, despite diltiazem infusion. Therefore, although the calcium channel blocker diltiazem effectively decreases cyclosporine-induced renal and hind limb vasoconstriction, it does not act by preventing endothelin release induced by cyclosporine stimulation.
Animals↗
Induction of immunosuppression with rabbit antithymocyte globulin: five-year experience in cardiac transplantation.
Perioperative induction of immunosuppressive treatment with rabbit antithymocyte globulin (RATG) and late introduction of cyclosporine was used in a group of 77 patients to prevent early renal dysfunction related to cyclosporine. Peak value in plasma creatinine during hospitalization for transplantation averaged 148 +/- 49 mmol/L in patients treated with RATG compared with 215 +/- 21 mmol/L in 39 patients initially treated without RATG induction (P = 0.01). Of patients treated with RATG, 65 +/- 6% remained free from acute rejection at six months versus 40 +/- 8% of untreated patients (P = 0.03). Rates of freedom from infection, from allograft coronary artery disease and from cancer are similar in both groups. Actuarial survival rates were identical in the two groups. The total number of lymphocytes, the percentage of T lymphocytes and of helper T cells were significantly lower when RATG was used. In conclusion, RATG prophylaxis given immediately after transplantation was well tolerated without complication and resulted in adequate immunosuppression to allow delayed introduction of maintenance treatment with cyclosporine.
Adult↗
Effect of internal mammary artery dissection on sternal vascularization.
Internal mammary artery (IMA) dissection may cause sternal devascularization and ischemia resulting in sternal wound complication. To evaluate the effect of median sternotomy and IMA dissection on sternal vascular supply, sternal bone tomography was performed 7 days and 1 month after cardiac operation in 67 patients. Seventeen nondiabetic patients had single IMA grafts, 18 had double IMA grafts, and 12 had only saphenous vein grafts or valve replacement. Twenty diabetic patients were studied after any one of these operations. Seven patients were restudied 1 month after the operation. Sternal technetium-99m-methylene diphosphate tomography was performed. The sternum was visualized and focal zones of hypoactivity represented sternal hypoperfusion. The ratio of hypoactivity area over total sternal area was calculated for every patient. After median sternotomy without single or double IMA grafts, the averaged hypoperfusion ratio was 4% +/- 1% compared with 13% +/- 3% after single IMA grafts and 24% +/- 6% after double IMA grafts (p less than 0.0001). Diabetic patients without IMA, with single IMA, and with double IMAs showed hypoperfusion areas of 5% +/- 3%, 15% +/- 5%, and 23% +/- 9%, respectively, a result similar to that of nondiabetic patients. One month after operation the hypoperfusion area decreased to 2% +/- 2% (p less than 0.05) in restudied patients. Our results indicate that IMA dissection causes a significant although partial and temporary sternal ischemia, which is more severe after double IMA than single IMA mobilization and which may be incriminated in the development of sternal wound infection. This vascularization defect was not greater among patients with diabetes mellitus.
Body Mass Index↗
[Salvage heart surgery after percutaneous mitral valvuloplasty].
Percutaneous mitral valvuloplasty (PMV) for selected patients with symptomatic mitral stenosis (MS) has been proposed as a safe alternative to open mitral commissurotomy (OMC) or mitral valvular replacement (MVR). Among 146 consecutive patients undergoing PMV from March 1987 to April 1990, 18 (12%) needed urgent (8) or delayed (10) (average 7 days) corrective surgery following PMV. There were 15 women and 3 men, with a clinical incapacity class II (3) or III (15), and with an intermediate risk for PMV according to echo score (mean = 8). The indications for corrective surgery were: massive mitral regurgitation due to tearing of the anterior leaflet (6), cardiac perforations (left atrium in 2, left ventricle in 3), PMV technical failure (5), severe atrial shunting (2). Operative procedures included MVR (14), cardiac wound suturing only (3), OMC (1). Operative mortality (30 days) was 22% (4/18), equally distributed among the urgent and delayed group. The causes of postoperative death were hemorrhage (2), severe cerebral ischemia (1) and sudden death (1). Compared to operative mortality after OMC (0/17.0%) or MVR (1/32, 3.1%) as the initial treatment for MS during the same time period, cardiac operation after failed or complicated PMV carried a significantly higher mortality (p = 0.004). Therefore, optimal patient selection and aggressive corrective surgery are necessary to decrease the PMV related mortality and morbidity.
Adult↗