Journal of the American College of Cardiology, 1998
Background: The fate of donor.transmitted athomeclcmtlo coronary lesions in cardiac transplant re... more Background: The fate of donor.transmitted athomeclcmtlo coronary lesions in cardiac transplant recipients remains completely unkown, Methods: Serial intreveaculer ultrasound was performed el baseline (4 weeks), 1 year and 2 years attar tranvplontatlon (moan 28 • 17, 370 ± 31, and 781 .-t; 49 days, respectively), For each examined SilO, maximal Intlmal thlckaess (Pmax) nnd Intlmnl area worn measured, Inttmsl area was defined am the difference between oxtamal alastlc membrane end luminal can,sectional ames, Donor,transmitted disaose woe, deflnod AS Pmax 0,5 ram, LeAIono worn classified am focal, whoa they Involved less than the ontlra length of {t segment es defined by the Camnaw artery Surgery study (CASS), Reality: Wo examined ~ag altos In 50 p~tlonts, At 29 sites In 22 patients (44%), ~t least one donor,transmitted athemsctemtlc lesion was present by ultmsouad, Donor.transmitted disease was mainly focal (26/29 ar 90%), The Pmax ~nd intlmal area of baseline (4 week) lesions averaged 0,?O ± 0,20 mm and ~,0~ • 1 ,~1 mm ~, m~pectlvely, At one year oxomlnatlcn, them was significant tncmaso In Pmax and Intlmal area at previously identified sties with lotions now averaging 0,g5 ~ 0,45 mm and 8,40 ~ 4,03 mm 0` p ,~ 0,02 and .O,01, respectively, Mslor progression, defined as a Pmax lnomaBe 0,3 mm occurred at 7 sites (30%) in 0 patients, Those lesions exhibited reduced locality by the one year exam (55% focal) Interestingly, at two year follow.up, the Pmax ~nd Intlmnl ~ro~ in donor.transmitted lesions did sot incmr~sa further, avaragtag 0,95 • 0,45 mm and 6,14 ± 3,99 mm p, Fecallty was largely unchanged compared to one year exam (62% focal). Concl~.¢l~,*,: Progression of donor athemselerosis is significant during the first year after tmn~plantetlon with mlnlmat changes In the subsequent year, The apparent "bum out" of donor.transmitted disease between 1 and 2 years following transplantation 9uggosls a relatively benign coume for this phenomenon.
Journal of the American College of Cardiology, 1998
The American College of Cardiolegy is pleased to announce that nearly 6,000 abstrn¢ts of original... more The American College of Cardiolegy is pleased to announce that nearly 6,000 abstrn¢ts of original contrihutlons were mbmitted to the Program Committee of the 47th Annual Scientific S~don. Space and time considerations thls year allowed the ~leetion of Z,260. Each abstract was peer reviewed by a panel of graders; chosen al~•lraets are presented in either oral or po~ter format. The Amedca.n College at" Cardl~!ogy thank~ the •0•
During percutaneous coronary intervention of the left anterior descending coronary artery, a lume... more During percutaneous coronary intervention of the left anterior descending coronary artery, a lumen narrowing was observed proximal to the stent just deployed. Intravascular ultrasound showed a hematoma localized outside the trilaminar wall structure in absence of a dissection flap or evidence of compression of the lumen. The luminal narrowing resolved after intracoronary administration of vasodilators. This finding is compatible with a coronary spasm triggered by an adventitial hematoma following stent deployment.
The injection of a single bolus of the gas phase of cigarette smoke into the airway of an isolate... more The injection of a single bolus of the gas phase of cigarette smoke into the airway of an isolated, perfused and ventilated, canine lung preparation resulted in a sevenfold increase in lung cyclic GMP content by 2 s after exposure. Recovery of control levels occurred by 2 min after injection. Repeated smoke exposures of the same lung resulted in similar increases. These results indicate that cigarette smoke may activate lung guanylate cyclase when delivered through the airway and suggest that lung cyclic GMP levels may fluctuate acutely during smoking.
A series of experiments was conducted to study in vitro and in vivo metal ion release and the uri... more A series of experiments was conducted to study in vitro and in vivo metal ion release and the urine excretion of metal ions. Metal salts were injected and urine analyzed. Anodic potentials were applied to stainless steel and cobalt-chromium-molybdenum (CCM) specimens to cause an acceleration of corrosion rates. Corrosion experiments were done in saline, 10% serum and in a subcutaneous space in hamsters. Corrosion rates were determined by measurements of weight loss and calculations of net charge transfer. Metal ion concentrations were determined with graphite furnace atomic absorption spectroscopy, and were calculated from total charge using Faraday's law. The results with stainless steel showed that the weight loss and metal ion release from stainless steel ii7 &ro and in vim can be calculated using Faraday's Law, assuming release in proportion to alloy composition. The results with CCM indicated that release rates in vifm can be used to determine the proportionality of release iri zlivo. All the nickel and most of the cobalt was rapidly excreted, while less than 50% of the chromium was excreted. The excretion of metals following salt injection or in oioo corrosion were very similar. INTRODUCTION A number of approaches have been taken to study corrosion and metal ion release from implants. Solid metal cylinders have been implanted in muscle in rabbits, and tissues and organs chemically analyzed for metal concen-tration~.'-~ These studies have demonstrated that metal ions are released and transported in vim. Black and co-workers4r5 have used metal powder in amounts corresponding to multiples of the surface area to body weight ratio of a total hip in a human. Their measurements of metal ion concentrations in blood components and urine have shown significant ion release, especially of nickel, which is not always in proportion to the alloy composition. Chemical analysis of tissues adjacent to implants in humans have also shown significant amounts of metal ions, especially chromium and titanium, which are not in proportion to alloy composition. 6-9 Chemical analysis of hair,"," serum,'2,L? and urine14-"j from animals and patients has also been performed as a way to determine release rates in zlivo. Chemical analysis of blood serum and cells have also demonstrated that chromium with a valence of + 6 is This paper was presented in part at the 12th Annual meeting of the Society for Bio
A study was conducted to determine the ability of hamsters to eliminate in the urine, or store in... more A study was conducted to determine the ability of hamsters to eliminate in the urine, or store in the organs, large quantities of metal salts given over a period of several months. In addition, the effect of prior immunization on metal ion clearance was determined. The results indicated that nickel was rapidly eliminated in the urine and that the level in the organs was similar to that of control animals. Cobalt was eliminated more slowly than was nickel. The organ levels of cobalt were similar to those of control animals with a slight elevation in the liver of the injected animals. Chromium was eliminated in the urine very slowly, was red cell associated, and the levels were elevated in all the organs (liver, lung, spleen, kidney) compared to control. Prior immunization with metal salts increased the storage of chromium.
Objective: Despite the link between positive coronary remodelling and acute ischaemic events, no ... more Objective: Despite the link between positive coronary remodelling and acute ischaemic events, no data exist about the impact of arterial remodelling on subsequent progression of coronary atherosclerosis. The objective of this study was to examine whether extent and direction of arterial remodelling are predictors of progression of coronary atherosclerosis. Design, setting and patients: From the Reversal of Atherosclerosis with Aggressive Lipid Lowering (REVERSAL) trial, 210 focal coronary lesions (single lesion per patient) were identified with (50% angiographic diameter stenosis at baseline intravascular ultrasound (IVUS). Remodelling was categorised using the remodelling index. Main outcome measures: Lesion sites were matched to the 18-month follow-up IVUS examination and change in atheroma area was calculated. Additionally, change in atheroma volume of the whole imaged artery was calculated. Results: There were no relationships between baseline remodelling index and change in atheroma area at the lesion site (r = 0.004, p = 0.96) or change in atheroma volume in the whole artery (r = 0.06, p = 0.37). Change in atheroma area was not significantly different in lesions with positive, negative or no remodelling at baseline (0.4 (SD 2.1) vs 0.7 (SD 1.7) vs 0.6 (SD 1.8) mm 2 , p = 0.76). Similarly, change in atheroma volume in the whole artery was not significantly different among the three remodelling categories (2.2 (SD 25.0) vs 1.4 (SD 31.2) vs 2.4 (SD 27.1) mm 3 , p = 0.98). Conclusions: Extent and direction of arterial remodelling do not predict subsequent progression of coronary atherosclerosis. Although positively remodelled lesions are associated with unstable clinical presentation, they are not associated with accelerated progression of atherosclerosis during lipid lowering therapy.
Background —The morphological characteristics of coronary plaques in patients with stable versus ... more Background —The morphological characteristics of coronary plaques in patients with stable versus unstable coronary syndromes have been described in vivo with intravascular ultrasound, but the relationship between arterial remodeling and clinical presentation is not well known. Methods and Results —We studied 85 patients with unstable and 46 patients with stable coronary syndromes using intravascular ultrasound before coronary intervention. The lesion site and a proximal reference site were analyzed. The remodeling ratio (RR) was defined as the ratio of the external elastic membrane (EEM) area at the lesion to that at the proximal reference site. Positive remodeling was defined as an RR >1.05 and negative remodeling as an RR <0.95. Plaque area (13.9±5.5 versus 11.1±4.8 mm 2 ; P =0.005), EEM area (16.1±6.2 versus 13.0±4.8 mm 2 ; P =0.004), and the RR (1.06±0.2 versus 0.94±0.2; P =0.008) were significantly greater at target lesions in patients with unstable syndromes than in pati...
Background —Transplant coronary artery disease is a combination of atherosclerosis transmitted fr... more Background —Transplant coronary artery disease is a combination of atherosclerosis transmitted from the donor and new lesions of allograft vasculopathy. We sought to determine the morphological characteristics of allograft vasculopathy and differentiate it from donor-transmitted atherosclerosis with serial intravascular ultrasound. Methods and Results —Intravascular ultrasound examination was performed in 93 patients at 27.2±15.0 and 369.7±23.9 days after transplantation. The maximally and minimally diseased sites were selected in each segment as defined by Coronary Artery Surgery Study classification. For each matched site, maximal plaque thickness was measured. Lesions (maximum plaque thickness ≥0.5 mm) present at baseline examination were defined as donor lesions. On follow-up, lesions that developed at previously normal sites were defined as de novo lesions. The distribution and severity of donor and de novo lesions were similar in proximal, mid, and distal segments. The de novo...
Background — Coronary artery disease is the major cause of late cardiac allograft failure. Howeve... more Background — Coronary artery disease is the major cause of late cardiac allograft failure. However, few data exist regarding the natural history of changes in intimal and external elastic membrane (EEM) areas after heart transplantation. Methods and Results — In 38 transplant recipients, serial intravascular ultrasound examinations were performed 3.7±2.2 weeks after transplantation and annually thereafter for 5 years. In 59 coronary arteries, we compared 135 matched segments among serial studies. In each segment, intravascular ultrasound images were digitized at 1-mm intervals, and mean values of EEM and lumen and intimal areas were analyzed. In the first year after transplantation, the intimal area increased significantly from 1.8±1.6 to 3.0±2.1 mm 2 ( P <0.001). Subsequently, the annual increase in intimal area decreased. EEM area did not change during the first year; however, between years 1 and 3, significant expansion of EEM area occurred (15.4±4.6 to 17.2±5.4 mm 2 , P <0...
Journal of the American College of Cardiology, 1998
Background: The fate of donor.transmitted athomeclcmtlo coronary lesions in cardiac transplant re... more Background: The fate of donor.transmitted athomeclcmtlo coronary lesions in cardiac transplant recipients remains completely unkown, Methods: Serial intreveaculer ultrasound was performed el baseline (4 weeks), 1 year and 2 years attar tranvplontatlon (moan 28 • 17, 370 ± 31, and 781 .-t; 49 days, respectively), For each examined SilO, maximal Intlmal thlckaess (Pmax) nnd Intlmnl area worn measured, Inttmsl area was defined am the difference between oxtamal alastlc membrane end luminal can,sectional ames, Donor,transmitted disaose woe, deflnod AS Pmax 0,5 ram, LeAIono worn classified am focal, whoa they Involved less than the ontlra length of {t segment es defined by the Camnaw artery Surgery study (CASS), Reality: Wo examined ~ag altos In 50 p~tlonts, At 29 sites In 22 patients (44%), ~t least one donor,transmitted athemsctemtlc lesion was present by ultmsouad, Donor.transmitted disease was mainly focal (26/29 ar 90%), The Pmax ~nd intlmal area of baseline (4 week) lesions averaged 0,?O ± 0,20 mm and ~,0~ • 1 ,~1 mm ~, m~pectlvely, At one year oxomlnatlcn, them was significant tncmaso In Pmax and Intlmal area at previously identified sties with lotions now averaging 0,g5 ~ 0,45 mm and 8,40 ~ 4,03 mm 0` p ,~ 0,02 and .O,01, respectively, Mslor progression, defined as a Pmax lnomaBe 0,3 mm occurred at 7 sites (30%) in 0 patients, Those lesions exhibited reduced locality by the one year exam (55% focal) Interestingly, at two year follow.up, the Pmax ~nd Intlmnl ~ro~ in donor.transmitted lesions did sot incmr~sa further, avaragtag 0,95 • 0,45 mm and 6,14 ± 3,99 mm p, Fecallty was largely unchanged compared to one year exam (62% focal). Concl~.¢l~,*,: Progression of donor athemselerosis is significant during the first year after tmn~plantetlon with mlnlmat changes In the subsequent year, The apparent "bum out" of donor.transmitted disease between 1 and 2 years following transplantation 9uggosls a relatively benign coume for this phenomenon.
Journal of the American College of Cardiology, 1998
The American College of Cardiolegy is pleased to announce that nearly 6,000 abstrn¢ts of original... more The American College of Cardiolegy is pleased to announce that nearly 6,000 abstrn¢ts of original contrihutlons were mbmitted to the Program Committee of the 47th Annual Scientific S~don. Space and time considerations thls year allowed the ~leetion of Z,260. Each abstract was peer reviewed by a panel of graders; chosen al~•lraets are presented in either oral or po~ter format. The Amedca.n College at" Cardl~!ogy thank~ the •0•
During percutaneous coronary intervention of the left anterior descending coronary artery, a lume... more During percutaneous coronary intervention of the left anterior descending coronary artery, a lumen narrowing was observed proximal to the stent just deployed. Intravascular ultrasound showed a hematoma localized outside the trilaminar wall structure in absence of a dissection flap or evidence of compression of the lumen. The luminal narrowing resolved after intracoronary administration of vasodilators. This finding is compatible with a coronary spasm triggered by an adventitial hematoma following stent deployment.
The injection of a single bolus of the gas phase of cigarette smoke into the airway of an isolate... more The injection of a single bolus of the gas phase of cigarette smoke into the airway of an isolated, perfused and ventilated, canine lung preparation resulted in a sevenfold increase in lung cyclic GMP content by 2 s after exposure. Recovery of control levels occurred by 2 min after injection. Repeated smoke exposures of the same lung resulted in similar increases. These results indicate that cigarette smoke may activate lung guanylate cyclase when delivered through the airway and suggest that lung cyclic GMP levels may fluctuate acutely during smoking.
A series of experiments was conducted to study in vitro and in vivo metal ion release and the uri... more A series of experiments was conducted to study in vitro and in vivo metal ion release and the urine excretion of metal ions. Metal salts were injected and urine analyzed. Anodic potentials were applied to stainless steel and cobalt-chromium-molybdenum (CCM) specimens to cause an acceleration of corrosion rates. Corrosion experiments were done in saline, 10% serum and in a subcutaneous space in hamsters. Corrosion rates were determined by measurements of weight loss and calculations of net charge transfer. Metal ion concentrations were determined with graphite furnace atomic absorption spectroscopy, and were calculated from total charge using Faraday's law. The results with stainless steel showed that the weight loss and metal ion release from stainless steel ii7 &ro and in vim can be calculated using Faraday's Law, assuming release in proportion to alloy composition. The results with CCM indicated that release rates in vifm can be used to determine the proportionality of release iri zlivo. All the nickel and most of the cobalt was rapidly excreted, while less than 50% of the chromium was excreted. The excretion of metals following salt injection or in oioo corrosion were very similar. INTRODUCTION A number of approaches have been taken to study corrosion and metal ion release from implants. Solid metal cylinders have been implanted in muscle in rabbits, and tissues and organs chemically analyzed for metal concen-tration~.'-~ These studies have demonstrated that metal ions are released and transported in vim. Black and co-workers4r5 have used metal powder in amounts corresponding to multiples of the surface area to body weight ratio of a total hip in a human. Their measurements of metal ion concentrations in blood components and urine have shown significant ion release, especially of nickel, which is not always in proportion to the alloy composition. Chemical analysis of tissues adjacent to implants in humans have also shown significant amounts of metal ions, especially chromium and titanium, which are not in proportion to alloy composition. 6-9 Chemical analysis of hair,"," serum,'2,L? and urine14-"j from animals and patients has also been performed as a way to determine release rates in zlivo. Chemical analysis of blood serum and cells have also demonstrated that chromium with a valence of + 6 is This paper was presented in part at the 12th Annual meeting of the Society for Bio
A study was conducted to determine the ability of hamsters to eliminate in the urine, or store in... more A study was conducted to determine the ability of hamsters to eliminate in the urine, or store in the organs, large quantities of metal salts given over a period of several months. In addition, the effect of prior immunization on metal ion clearance was determined. The results indicated that nickel was rapidly eliminated in the urine and that the level in the organs was similar to that of control animals. Cobalt was eliminated more slowly than was nickel. The organ levels of cobalt were similar to those of control animals with a slight elevation in the liver of the injected animals. Chromium was eliminated in the urine very slowly, was red cell associated, and the levels were elevated in all the organs (liver, lung, spleen, kidney) compared to control. Prior immunization with metal salts increased the storage of chromium.
Objective: Despite the link between positive coronary remodelling and acute ischaemic events, no ... more Objective: Despite the link between positive coronary remodelling and acute ischaemic events, no data exist about the impact of arterial remodelling on subsequent progression of coronary atherosclerosis. The objective of this study was to examine whether extent and direction of arterial remodelling are predictors of progression of coronary atherosclerosis. Design, setting and patients: From the Reversal of Atherosclerosis with Aggressive Lipid Lowering (REVERSAL) trial, 210 focal coronary lesions (single lesion per patient) were identified with (50% angiographic diameter stenosis at baseline intravascular ultrasound (IVUS). Remodelling was categorised using the remodelling index. Main outcome measures: Lesion sites were matched to the 18-month follow-up IVUS examination and change in atheroma area was calculated. Additionally, change in atheroma volume of the whole imaged artery was calculated. Results: There were no relationships between baseline remodelling index and change in atheroma area at the lesion site (r = 0.004, p = 0.96) or change in atheroma volume in the whole artery (r = 0.06, p = 0.37). Change in atheroma area was not significantly different in lesions with positive, negative or no remodelling at baseline (0.4 (SD 2.1) vs 0.7 (SD 1.7) vs 0.6 (SD 1.8) mm 2 , p = 0.76). Similarly, change in atheroma volume in the whole artery was not significantly different among the three remodelling categories (2.2 (SD 25.0) vs 1.4 (SD 31.2) vs 2.4 (SD 27.1) mm 3 , p = 0.98). Conclusions: Extent and direction of arterial remodelling do not predict subsequent progression of coronary atherosclerosis. Although positively remodelled lesions are associated with unstable clinical presentation, they are not associated with accelerated progression of atherosclerosis during lipid lowering therapy.
Background —The morphological characteristics of coronary plaques in patients with stable versus ... more Background —The morphological characteristics of coronary plaques in patients with stable versus unstable coronary syndromes have been described in vivo with intravascular ultrasound, but the relationship between arterial remodeling and clinical presentation is not well known. Methods and Results —We studied 85 patients with unstable and 46 patients with stable coronary syndromes using intravascular ultrasound before coronary intervention. The lesion site and a proximal reference site were analyzed. The remodeling ratio (RR) was defined as the ratio of the external elastic membrane (EEM) area at the lesion to that at the proximal reference site. Positive remodeling was defined as an RR >1.05 and negative remodeling as an RR <0.95. Plaque area (13.9±5.5 versus 11.1±4.8 mm 2 ; P =0.005), EEM area (16.1±6.2 versus 13.0±4.8 mm 2 ; P =0.004), and the RR (1.06±0.2 versus 0.94±0.2; P =0.008) were significantly greater at target lesions in patients with unstable syndromes than in pati...
Background —Transplant coronary artery disease is a combination of atherosclerosis transmitted fr... more Background —Transplant coronary artery disease is a combination of atherosclerosis transmitted from the donor and new lesions of allograft vasculopathy. We sought to determine the morphological characteristics of allograft vasculopathy and differentiate it from donor-transmitted atherosclerosis with serial intravascular ultrasound. Methods and Results —Intravascular ultrasound examination was performed in 93 patients at 27.2±15.0 and 369.7±23.9 days after transplantation. The maximally and minimally diseased sites were selected in each segment as defined by Coronary Artery Surgery Study classification. For each matched site, maximal plaque thickness was measured. Lesions (maximum plaque thickness ≥0.5 mm) present at baseline examination were defined as donor lesions. On follow-up, lesions that developed at previously normal sites were defined as de novo lesions. The distribution and severity of donor and de novo lesions were similar in proximal, mid, and distal segments. The de novo...
Background — Coronary artery disease is the major cause of late cardiac allograft failure. Howeve... more Background — Coronary artery disease is the major cause of late cardiac allograft failure. However, few data exist regarding the natural history of changes in intimal and external elastic membrane (EEM) areas after heart transplantation. Methods and Results — In 38 transplant recipients, serial intravascular ultrasound examinations were performed 3.7±2.2 weeks after transplantation and annually thereafter for 5 years. In 59 coronary arteries, we compared 135 matched segments among serial studies. In each segment, intravascular ultrasound images were digitized at 1-mm intervals, and mean values of EEM and lumen and intimal areas were analyzed. In the first year after transplantation, the intimal area increased significantly from 1.8±1.6 to 3.0±2.1 mm 2 ( P <0.001). Subsequently, the annual increase in intimal area decreased. EEM area did not change during the first year; however, between years 1 and 3, significant expansion of EEM area occurred (15.4±4.6 to 17.2±5.4 mm 2 , P <0...
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