Benoit Varennes - Academia.edu (original) (raw)

Papers by Benoit Varennes

Research paper thumbnail of Repair of chronic ischemic mitral regurgitation with posterior leaflet extension

European Journal of Cardio-Thoracic Surgery, 2010

We read with great interest the review article 'Chronic ischaemic mitral regurgitation -current t... more We read with great interest the review article 'Chronic ischaemic mitral regurgitation -current treatment results and new mechanism-based surgical approaches' by Bouma and colleagues in a past issue of this journal [1]. Management of severe ischaemic mitral regurgitation remains challenging with disappointing long-term surgical results. Furthermore, despite the increasing popularity of valve repair, its longterm durability in chronic ischaemic mitral regurgitation continues to be uncertain. In this article, the authors worked in an excellent manner to review the different mechanisms of ischaemic mitral regurgitation, and to describe the variety of surgical approaches used to deal with this entity.

Research paper thumbnail of Intraoperative Duplex Study of Internal Thoracic Artery Spasm During Coronary Bypass

Journal of Cardiac Surgery, 1997

In this article, we document flow disturbance due to internal thoracic artery spasm (ITA) in a pa... more 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. (J Card Surg 1997;12:403-

Research paper thumbnail of Clinical death and the measurement of stressed vascular volume

Critical Care Medicine, 1998

To measure stressed vascular volume in humans and to review the concepts of stressed and unstress... more To measure stressed vascular volume in humans and to review the concepts of stressed and unstressed vascular volume. Observational study during surgical procedure. Operating room at a university hospital. Five patients undergoing hypothermic circulatory arrest for surgery on major vessels. We measured the volume that drained from the patient to the reservoir of the pump when the pump was turned off. Stressed volume was 20.2+/-1.0 mL/kg, which is 30% of the predicted blood volume of these patients. 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.

Research paper thumbnail of Initial Results of Posterior Leaflet Extension for Severe Type IIIb Ischemic Mitral Regurgitation

Circulation, 2009

http://circ.ahajournals.org located on the World Wide Web at:

Research paper thumbnail of Combined heart and liver transplantation on cardiopulmonary bypass: report of four cases

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2010

Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and li... more Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and liver disease. First performed during cardiopulmonary bypass and anticoagulation, subsequent concerns about increased bleeding changed the strategy to performing liver implantation following separation from cardiopulmonary bypass. Considering the overall decrease in transfusion requirements during liver transplant and the potential benefits to the transplanted heart to remain on cardiopulmonary bypass during liver implantation, we revised the strategy for combined heart and liver transplant. We report the clinical course of four consecutive patients who underwent this procedure in our institution. Clinical features Patient 1 was a 53-yr-old male with familial hypertrophic cardiomyopathy and congestive cirrhosis. Patient 2 was a 57-yr-old male with hypertrophic restrictive cardiomyopathy and congestive cirrhosis. Patient 3 was a 48-yr-old male with dilated cadiomyopathy and hepatitis B cirrhosis. Patient 4 was a 57-yr-old male with ischemic cardiomyopathy and congestive cirrhosis. Each patient underwent combined heart and liver transplant, with liver implantation performed during cardiopulmonary bypass and anticoagulation. Estimated blood loss ranged from 1,000 to 3,000 mL. Intraoperative transfusion included 2-5 U of packed red blood cells, 4-12 U of fresh frozen plasma, 0-20 U of cryoprecipitate, and 5-23 U of platelets. All patients remain well 25-38 months after surgery. Conclusion Combined heart and liver transplant during cardiopulmonary bypass is a viable strategy that may confer benefit to this unique type of patient.

Research paper thumbnail of Vascular Calcifications in Homozygote Familial Hypercholesterolemia

Arteriosclerosis, Thrombosis, and Vascular Biology, 2008

Background-Patients with homozygous familial hypercholesterolemia (hmzFH) attributable to LDL rec... more 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 19Ϯ5 mmol/L (737Ϯ206 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 ϭ0.53, Pϭ0.001). 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. (Arterioscler Thromb Vasc Biol. 2008;28:777-785)

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

Transplantation, Jan 27, 1999

Based on the excellent correlation between cyclosporine A 2-hr postdose blood levels (C2) and the... more 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. 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). During period 1, Neoral dose, cyclosporine A, C0 and C2, and serum creatinine, decreased by 26, 56, 45, and 2.3%, respectiv...

Research paper thumbnail of The effect of using microplegia on perioperative morbidity and mortality in elderly patients undergoing cardiac surgery

Interactive CardioVascular and Thoracic Surgery, 2009

Old age is a significant risk factor for perioperative morbidity and mortality following cardiac ... more Old age is a significant risk factor for perioperative morbidity and mortality following cardiac surgery and optimal myocardial protection strategy should be sought in this group of patients. We, therefore, reviewed the data on 295 consecutive patients older than 75 years who underwent any cardiac surgical procedure. Microplegia was used in 144 patients compared to 151 patients who had the standard 4:1 blood cardioplegia. Logistic regression analysis was used for propensity matching to balance the differences between the two groups. The microplegia group included more females and sicker patients as indicated by higher Parsonnet scores. There were differences in the pump time, aortic cross-clamp time, procedure type and surgeons between the two groups. These differences were balanced using the propensity matching. In-hospital mortality, acute renal injury and confusion were higher in the microplegia group (17%, 34%, 35%, respectively) compared to the standard 4:1 cardioplegia group (9%, 23%, 24%, respectively) (Ps0.04, 0.04, 0.04, respectively). These differences were not statistically significant after propensity matching. These results demonstrate that the use of microplegia is safe in patients older than 75 years who are undergoing cardiac surgery and results in similar in-hospital morbidity and mortality to the standard 4:1 blood cardioplegia.

Research paper thumbnail of Clinical Benefit of Neoral Dose Monitoring with Cyclosporine 2HR Postdose Levels Compared to Trough Levels in Stable Heart Transplant Patients

Transplantation, 1999

Based on the excellent correlation between cyclosporine A 2-hr postdose blood levels (C2) and the... more 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. 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). 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). In stable heart transplant patients, a greater clinical benefit was observed when Neoral dose monitoring was performed according to C2, compared with C0.

Research paper thumbnail of Neoral dose monitoring with cyclosporine 2-hour postdose levels in heart transplant patients receiving anti-thymocyte globulin induction

Transplantation Proceedings, 2000

Research paper thumbnail of A multicenter randomized controlled trial to assess the feasibility of testing modified ultrafiltration as a blood conservation technology in cardiac surgery

The Journal of Thoracic and Cardiovascular Surgery, 2010

Objectives: Modified ultrafiltration is a technique after cardiopulmonary bypass whereby blood wi... more Objectives: Modified ultrafiltration is a technique after cardiopulmonary bypass whereby blood withdrawn from the aortic cannula is passed across a semipermeable membrane to hemoconcentrate. Unblinded trials have suggested that modified ultrafiltration is efficacious for blood conservation. The objective of this trial was to assess the feasibility of a model testing modified ultrafiltration in which all members of the surgical team were blinded to the intervention.

Research paper thumbnail of Use of heparinase I in a patient with protamine allergy undergoing redo myocardial revascularization

Journal of Cardiothoracic and Vascular Anesthesia, 2000

Research paper thumbnail of Anesthesia for deep hypothermic circulatory arrest in adults: Experience with the first 50 patients

Journal of Cardiothoracic and Vascular Anesthesia, 1998

monitor the nasopharyngeal temperature (NPT) and urinary bladder temperature (UBT), (attached to ... more monitor the nasopharyngeal temperature (NPT) and urinary bladder temperature (UBT), (attached to the Foley catheter).

Research paper thumbnail of Sternotomy After Muscle Flap Repair of Sternal Osteomyelitis and Mediastinitis

Journal of Cardiac Surgery, 1990

A 61-year-old man who had undergone aortocoronary bypass developed sternal osteomyelitis and medi... more 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.

Research paper thumbnail of Chest Wall Infarction Following Bilateral Internal Mammary to Coronary Arterial Bypass in a Patient with a Thoracoabdominal Aneurysm

Journal of Cardiac Surgery, 1997

A 69-year-old man with severe peripheral vascular disease and a known thoracoabdominal aortic ane... more 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.

Research paper thumbnail of Reinfusion of Mediastinal Blood in CABG Patients: Impact on Homologous Transfusions and Rate of Re-exploration

Journal of Cardiac Surgery, 1996

Reinfusion of mediastinal shed blood after cardiac surgery has been used in some centers to reduc... more 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. 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. 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). 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.

Research paper thumbnail of Clinical benefit of neoral dose monitoring with cyclosporine 2-hour peak levels compared to trough levels in stable heart transplant patients

Journal of Heart and Lung Transplantation, 1999

78 Abstracts effects on intimal hyperpiasia might be found late after HTX as well. Between l/97 a... more 78 Abstracts effects on intimal hyperpiasia might be found late after HTX as well. Between l/97 and 2/98 30 patients (2.0 + 1.1 years post HTX) were enrolled in this study. Following a baseline examination with intravascular ultrasound (IVUS, volumetric assessment of plaque-, lumen-and vessel volume), pts were prospectively randomized to receive either MMF (2g/day) or to continue with AZA as part of a triple immunosuppresson (CyA, Pred). One year follow up is completed in 20 patients so far. It was found that despite a larger increase in plaque volume (p=ns), MMF treated patients were characterized by an increase in vessel dimensions even overcompensating increase in plaque mass (fiaure. o=O.O5). I puqm int&.dm l"mm-din These preliminary results demonstrate, that luminal loss in CAV might not only be influenced by intimal hyperplasia but by vascular constriction as well. Treatment with MMF was shown to have a favorable effect in the prevention of vascular constriction, maintaining coronary lumen and nutritive graff perfusion.

Research paper thumbnail of Pentastarch Versus Albumin in Cardiopulmonary Bypass Prime: Impact on Blood Loss

Echocardiography, 1985

Albumin is commonly used as a volume expander in cardiopulmonary bypass (CPB) prime. Pentastarch,... more 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. 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. 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. 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.

Research paper thumbnail of Initial Results of Posterior Leaflet Extension for Severe Type IIIb Ischemic Mitral Regurgitation

Background-Management of severe ischemic mitral regurgitation remains difficult with disappointin... more Background-Management of severe ischemic mitral regurgitation remains difficult with disappointing early and intermediate-term surgical results of valve repair. Methods and Results-Forty-four patients with severe (4ϩ) Carpentier type IIIb ischemic mitral regurgitation underwent mitral valve repair, with or without surgical revascularization, by posterior leaflet extension with a patch of bovine pericardium and a remodeling annuloplasty. Serial echocardiography was performed preoperatively, intraoperatively, and postoperatively to assess mitral valve competence. The postoperative functional status of patients was assessed. The average Parsonnet score was 38Ϯ13. Thirty-day mortality was 11%, and late mortality was 14%. Mean follow-up was 38 months. The actuarial freedom from moderate or severe recurrent mitral regurgitation was 90% at 2 years, whereas 90% of patients were in New York Heart Association class I at 2 years. Conclusion-Posterior leaflet extension with annuloplasty of the mitral valve for severe type IIIb ischemic regurgitation is a safe, effective method that provides good early and intermediate-term competence of the mitral valve and therefore good functional status.

Research paper thumbnail of Combined heart and liver transplantation on cardiopulmonary bypass: report of four cases

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2010

Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and li... more Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and liver disease. First performed during cardiopulmonary bypass and anticoagulation, subsequent concerns about increased bleeding changed the strategy to performing liver implantation following separation from cardiopulmonary bypass. Considering the overall decrease in transfusion requirements during liver transplant and the potential benefits to the transplanted heart to remain on cardiopulmonary bypass during liver implantation, we revised the strategy for combined heart and liver transplant. We report the clinical course of four consecutive patients who underwent this procedure in our institution. Clinical features Patient 1 was a 53-yr-old male with familial hypertrophic cardiomyopathy and congestive cirrhosis. Patient 2 was a 57-yr-old male with hypertrophic restrictive cardiomyopathy and congestive cirrhosis. Patient 3 was a 48-yr-old male with dilated cadiomyopathy and hepatitis B cirrhosis. Patient 4 was a 57-yr-old male with ischemic cardiomyopathy and congestive cirrhosis. Each patient underwent combined heart and liver transplant, with liver implantation performed during cardiopulmonary bypass and anticoagulation. Estimated blood loss ranged from 1,000 to 3,000 mL. Intraoperative transfusion included 2-5 U of packed red blood cells, 4-12 U of fresh frozen plasma, 0-20 U of cryoprecipitate, and 5-23 U of platelets. All patients remain well 25-38 months after surgery. Conclusion Combined heart and liver transplant during cardiopulmonary bypass is a viable strategy that may confer benefit to this unique type of patient.

Research paper thumbnail of Repair of chronic ischemic mitral regurgitation with posterior leaflet extension

European Journal of Cardio-Thoracic Surgery, 2010

We read with great interest the review article 'Chronic ischaemic mitral regurgitation -current t... more We read with great interest the review article 'Chronic ischaemic mitral regurgitation -current treatment results and new mechanism-based surgical approaches' by Bouma and colleagues in a past issue of this journal [1]. Management of severe ischaemic mitral regurgitation remains challenging with disappointing long-term surgical results. Furthermore, despite the increasing popularity of valve repair, its longterm durability in chronic ischaemic mitral regurgitation continues to be uncertain. In this article, the authors worked in an excellent manner to review the different mechanisms of ischaemic mitral regurgitation, and to describe the variety of surgical approaches used to deal with this entity.

Research paper thumbnail of Intraoperative Duplex Study of Internal Thoracic Artery Spasm During Coronary Bypass

Journal of Cardiac Surgery, 1997

In this article, we document flow disturbance due to internal thoracic artery spasm (ITA) in a pa... more 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. (J Card Surg 1997;12:403-

Research paper thumbnail of Clinical death and the measurement of stressed vascular volume

Critical Care Medicine, 1998

To measure stressed vascular volume in humans and to review the concepts of stressed and unstress... more To measure stressed vascular volume in humans and to review the concepts of stressed and unstressed vascular volume. Observational study during surgical procedure. Operating room at a university hospital. Five patients undergoing hypothermic circulatory arrest for surgery on major vessels. We measured the volume that drained from the patient to the reservoir of the pump when the pump was turned off. Stressed volume was 20.2+/-1.0 mL/kg, which is 30% of the predicted blood volume of these patients. 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.

Research paper thumbnail of Initial Results of Posterior Leaflet Extension for Severe Type IIIb Ischemic Mitral Regurgitation

Circulation, 2009

http://circ.ahajournals.org located on the World Wide Web at:

Research paper thumbnail of Combined heart and liver transplantation on cardiopulmonary bypass: report of four cases

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2010

Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and li... more Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and liver disease. First performed during cardiopulmonary bypass and anticoagulation, subsequent concerns about increased bleeding changed the strategy to performing liver implantation following separation from cardiopulmonary bypass. Considering the overall decrease in transfusion requirements during liver transplant and the potential benefits to the transplanted heart to remain on cardiopulmonary bypass during liver implantation, we revised the strategy for combined heart and liver transplant. We report the clinical course of four consecutive patients who underwent this procedure in our institution. Clinical features Patient 1 was a 53-yr-old male with familial hypertrophic cardiomyopathy and congestive cirrhosis. Patient 2 was a 57-yr-old male with hypertrophic restrictive cardiomyopathy and congestive cirrhosis. Patient 3 was a 48-yr-old male with dilated cadiomyopathy and hepatitis B cirrhosis. Patient 4 was a 57-yr-old male with ischemic cardiomyopathy and congestive cirrhosis. Each patient underwent combined heart and liver transplant, with liver implantation performed during cardiopulmonary bypass and anticoagulation. Estimated blood loss ranged from 1,000 to 3,000 mL. Intraoperative transfusion included 2-5 U of packed red blood cells, 4-12 U of fresh frozen plasma, 0-20 U of cryoprecipitate, and 5-23 U of platelets. All patients remain well 25-38 months after surgery. Conclusion Combined heart and liver transplant during cardiopulmonary bypass is a viable strategy that may confer benefit to this unique type of patient.

Research paper thumbnail of Vascular Calcifications in Homozygote Familial Hypercholesterolemia

Arteriosclerosis, Thrombosis, and Vascular Biology, 2008

Background-Patients with homozygous familial hypercholesterolemia (hmzFH) attributable to LDL rec... more 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 19Ϯ5 mmol/L (737Ϯ206 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 ϭ0.53, Pϭ0.001). 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. (Arterioscler Thromb Vasc Biol. 2008;28:777-785)

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

Transplantation, Jan 27, 1999

Based on the excellent correlation between cyclosporine A 2-hr postdose blood levels (C2) and the... more 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. 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). During period 1, Neoral dose, cyclosporine A, C0 and C2, and serum creatinine, decreased by 26, 56, 45, and 2.3%, respectiv...

Research paper thumbnail of The effect of using microplegia on perioperative morbidity and mortality in elderly patients undergoing cardiac surgery

Interactive CardioVascular and Thoracic Surgery, 2009

Old age is a significant risk factor for perioperative morbidity and mortality following cardiac ... more Old age is a significant risk factor for perioperative morbidity and mortality following cardiac surgery and optimal myocardial protection strategy should be sought in this group of patients. We, therefore, reviewed the data on 295 consecutive patients older than 75 years who underwent any cardiac surgical procedure. Microplegia was used in 144 patients compared to 151 patients who had the standard 4:1 blood cardioplegia. Logistic regression analysis was used for propensity matching to balance the differences between the two groups. The microplegia group included more females and sicker patients as indicated by higher Parsonnet scores. There were differences in the pump time, aortic cross-clamp time, procedure type and surgeons between the two groups. These differences were balanced using the propensity matching. In-hospital mortality, acute renal injury and confusion were higher in the microplegia group (17%, 34%, 35%, respectively) compared to the standard 4:1 cardioplegia group (9%, 23%, 24%, respectively) (Ps0.04, 0.04, 0.04, respectively). These differences were not statistically significant after propensity matching. These results demonstrate that the use of microplegia is safe in patients older than 75 years who are undergoing cardiac surgery and results in similar in-hospital morbidity and mortality to the standard 4:1 blood cardioplegia.

Research paper thumbnail of Clinical Benefit of Neoral Dose Monitoring with Cyclosporine 2HR Postdose Levels Compared to Trough Levels in Stable Heart Transplant Patients

Transplantation, 1999

Based on the excellent correlation between cyclosporine A 2-hr postdose blood levels (C2) and the... more 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. 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). 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). In stable heart transplant patients, a greater clinical benefit was observed when Neoral dose monitoring was performed according to C2, compared with C0.

Research paper thumbnail of Neoral dose monitoring with cyclosporine 2-hour postdose levels in heart transplant patients receiving anti-thymocyte globulin induction

Transplantation Proceedings, 2000

Research paper thumbnail of A multicenter randomized controlled trial to assess the feasibility of testing modified ultrafiltration as a blood conservation technology in cardiac surgery

The Journal of Thoracic and Cardiovascular Surgery, 2010

Objectives: Modified ultrafiltration is a technique after cardiopulmonary bypass whereby blood wi... more Objectives: Modified ultrafiltration is a technique after cardiopulmonary bypass whereby blood withdrawn from the aortic cannula is passed across a semipermeable membrane to hemoconcentrate. Unblinded trials have suggested that modified ultrafiltration is efficacious for blood conservation. The objective of this trial was to assess the feasibility of a model testing modified ultrafiltration in which all members of the surgical team were blinded to the intervention.

Research paper thumbnail of Use of heparinase I in a patient with protamine allergy undergoing redo myocardial revascularization

Journal of Cardiothoracic and Vascular Anesthesia, 2000

Research paper thumbnail of Anesthesia for deep hypothermic circulatory arrest in adults: Experience with the first 50 patients

Journal of Cardiothoracic and Vascular Anesthesia, 1998

monitor the nasopharyngeal temperature (NPT) and urinary bladder temperature (UBT), (attached to ... more monitor the nasopharyngeal temperature (NPT) and urinary bladder temperature (UBT), (attached to the Foley catheter).

Research paper thumbnail of Sternotomy After Muscle Flap Repair of Sternal Osteomyelitis and Mediastinitis

Journal of Cardiac Surgery, 1990

A 61-year-old man who had undergone aortocoronary bypass developed sternal osteomyelitis and medi... more 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.

Research paper thumbnail of Chest Wall Infarction Following Bilateral Internal Mammary to Coronary Arterial Bypass in a Patient with a Thoracoabdominal Aneurysm

Journal of Cardiac Surgery, 1997

A 69-year-old man with severe peripheral vascular disease and a known thoracoabdominal aortic ane... more 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.

Research paper thumbnail of Reinfusion of Mediastinal Blood in CABG Patients: Impact on Homologous Transfusions and Rate of Re-exploration

Journal of Cardiac Surgery, 1996

Reinfusion of mediastinal shed blood after cardiac surgery has been used in some centers to reduc... more 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. 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. 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). 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.

Research paper thumbnail of Clinical benefit of neoral dose monitoring with cyclosporine 2-hour peak levels compared to trough levels in stable heart transplant patients

Journal of Heart and Lung Transplantation, 1999

78 Abstracts effects on intimal hyperpiasia might be found late after HTX as well. Between l/97 a... more 78 Abstracts effects on intimal hyperpiasia might be found late after HTX as well. Between l/97 and 2/98 30 patients (2.0 + 1.1 years post HTX) were enrolled in this study. Following a baseline examination with intravascular ultrasound (IVUS, volumetric assessment of plaque-, lumen-and vessel volume), pts were prospectively randomized to receive either MMF (2g/day) or to continue with AZA as part of a triple immunosuppresson (CyA, Pred). One year follow up is completed in 20 patients so far. It was found that despite a larger increase in plaque volume (p=ns), MMF treated patients were characterized by an increase in vessel dimensions even overcompensating increase in plaque mass (fiaure. o=O.O5). I puqm int&.dm l"mm-din These preliminary results demonstrate, that luminal loss in CAV might not only be influenced by intimal hyperplasia but by vascular constriction as well. Treatment with MMF was shown to have a favorable effect in the prevention of vascular constriction, maintaining coronary lumen and nutritive graff perfusion.

Research paper thumbnail of Pentastarch Versus Albumin in Cardiopulmonary Bypass Prime: Impact on Blood Loss

Echocardiography, 1985

Albumin is commonly used as a volume expander in cardiopulmonary bypass (CPB) prime. Pentastarch,... more 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. 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. 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. 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.

Research paper thumbnail of Initial Results of Posterior Leaflet Extension for Severe Type IIIb Ischemic Mitral Regurgitation

Background-Management of severe ischemic mitral regurgitation remains difficult with disappointin... more Background-Management of severe ischemic mitral regurgitation remains difficult with disappointing early and intermediate-term surgical results of valve repair. Methods and Results-Forty-four patients with severe (4ϩ) Carpentier type IIIb ischemic mitral regurgitation underwent mitral valve repair, with or without surgical revascularization, by posterior leaflet extension with a patch of bovine pericardium and a remodeling annuloplasty. Serial echocardiography was performed preoperatively, intraoperatively, and postoperatively to assess mitral valve competence. The postoperative functional status of patients was assessed. The average Parsonnet score was 38Ϯ13. Thirty-day mortality was 11%, and late mortality was 14%. Mean follow-up was 38 months. The actuarial freedom from moderate or severe recurrent mitral regurgitation was 90% at 2 years, whereas 90% of patients were in New York Heart Association class I at 2 years. Conclusion-Posterior leaflet extension with annuloplasty of the mitral valve for severe type IIIb ischemic regurgitation is a safe, effective method that provides good early and intermediate-term competence of the mitral valve and therefore good functional status.

Research paper thumbnail of Combined heart and liver transplantation on cardiopulmonary bypass: report of four cases

Canadian Journal of Anesthesia/Journal canadien d'anesthésie, 2010

Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and li... more Purpose Combined heart and liver transplant is a rare procedure to treat end-stage cardiac and liver disease. First performed during cardiopulmonary bypass and anticoagulation, subsequent concerns about increased bleeding changed the strategy to performing liver implantation following separation from cardiopulmonary bypass. Considering the overall decrease in transfusion requirements during liver transplant and the potential benefits to the transplanted heart to remain on cardiopulmonary bypass during liver implantation, we revised the strategy for combined heart and liver transplant. We report the clinical course of four consecutive patients who underwent this procedure in our institution. Clinical features Patient 1 was a 53-yr-old male with familial hypertrophic cardiomyopathy and congestive cirrhosis. Patient 2 was a 57-yr-old male with hypertrophic restrictive cardiomyopathy and congestive cirrhosis. Patient 3 was a 48-yr-old male with dilated cadiomyopathy and hepatitis B cirrhosis. Patient 4 was a 57-yr-old male with ischemic cardiomyopathy and congestive cirrhosis. Each patient underwent combined heart and liver transplant, with liver implantation performed during cardiopulmonary bypass and anticoagulation. Estimated blood loss ranged from 1,000 to 3,000 mL. Intraoperative transfusion included 2-5 U of packed red blood cells, 4-12 U of fresh frozen plasma, 0-20 U of cryoprecipitate, and 5-23 U of platelets. All patients remain well 25-38 months after surgery. Conclusion Combined heart and liver transplant during cardiopulmonary bypass is a viable strategy that may confer benefit to this unique type of patient.