- Email: [email protected]
Cost-Effectiveness of Drug-Eluting Stents in Large (≥3.5 mm) Coronary Arteries
Abstracts CSANZ Abstracts 2011
S29
infusions (IC dextrose) were performed in four patients (21 segments). Macrovascular response [% change segmental lumen volume (SLV)] and plaque burden [percent atheroma volume (PAV)] were studied in 5-mm coronary segments. Microvascular response [percent change in coronary blood flow (CBF)], was calculated following each infusion. Results: IC salbutamol demonstrated significant doseresponse SLV and CBF from baseline respectively (0.15 g/min: 3.5 ± 1.3%, 28 ± 14%, p = 0.04, p = NS; 0.30 g/min: 5.5 ± 1.4%, 54 ± 17%, p = 0.001, p < 0.0001; 0.60 g/min: 4.8 ± 1.6%, 66 ± 15%, p = 0.02, p < 0.0001), with SLV responses further exemplified in low versus high plaque burden groups. Salbutamol vasomotor responses were abolished by L-NMMA, supporting nitric oxidedependent mechanisms. Vehicle infusions resulted in no significant SLV or CBF. Multivariate analysis including conventional cardiovascular risk factors, PAV, segmental remodeling and plaque eccentricity indices identified PAV as the only significant predictor of a SLV to IC salbutamol (coefficient −0.18, 95% CI −0.32 to −0.044, p = 0.015). Conclusions: Intracoronary salbutamol is a novel endothelium-dependent epicardial and microvascular coronary vasodilator. IVUS-derived plaque burden is a major determinant of focal coronary endothelial function.
cant relationship between IMR and CR, described by: IMR = (0.0023 × CR + 0.06)−1 r = 0.73, p < 0.001. A ≥5% relative increase in CR identified an IMR of <16 with 100% sensitivity and 100% specificity (AUC = 1.0); and an IMR of <25 with 100% sensitivity and 75% specificity (AUC = 0.90).
doi:10.1016/j.hlc.2011.05.073
doi:10.1016/j.hlc.2011.05.074
71 Coronary Endothelial Function by the Index of Microcirculatory Resistance can be Estimated by Evaluating Left Ventricular Contractile Reserve at Low Dose Dobutamine Echocardiography
72 Cost-Effectiveness of Drug-Eluting Stents in Large (≥3.5 mm) Coronary Arteries
M. Leung ∗ , S. Lo, C. Juergens, D. Leung Liverpool Hospital, Sydney, Australia Coronary endothelial function has important diagnostic and prognostic implications but its routine assessment is difficult. The index of microcirculatory resistance (IMR) is considered a reliable but invasive measure. We hypothesised that left ventricular (LV) contractile reserve (CR) measured with strain imaging at low dose dobutamine echocardiography (echo) is a reliable non-invasive surrogate of IMR in patients without significant epicardial disease. Methods: Twenty-two patients (15 men, aged 59 ± 8 years, 15 DM, mean ejection fraction 65%, range 31–81%, none had significant epicardial coronary disease by fractional flow reserve) underwent low dose dobutamine echo and invasive coronary angiography. Global mean peak systolic longitudinal strain was measured in the three apical views at rest and low dose dobutamine echo with CR defined as the difference between the resting and low dose values. IMR was measured in the left anterior descending artery at angiography. Results: The mean IMR was 19.34 (range 7–104) and mean peak global systolic strain at rest was −17.56% and at low dose −19.02 corresponding to a mean CR of +1.45% (9% relative increase). There was a signifi-
Conclusions: LV CR measured with strain imaging at low dose dobutamine echo may be used to estimate IMR as a measure of coronary microvascular function in patients without significant coronary artery disease.
B. Yan 1,∗ , M. Liu 1 , V. Lee 1 , C. Reid 2 , C. Yu 1 1 Chinese 2 Monash
University of Hong Kong, Hong Kong University, Melbourne, Australia
Background: Percutaneous coronary intervention (PCI) with bare-metal stent (BMS) implantation in large coronary vessels (≥3.5 mm) is associated with low risk of restenosis that is comparable to drug-eluting stents (DES). We aim to assess the cost-effectiveness of DES compared to BMS in large coronary vessels. Methods: We analysed 225 consecutive patients undergoing PCI with ≥3.5 mm stent at our institution from September 2009 to July 2010. Clinical outcomes were measured by the occurrence of major adverse cardiac events [MACE, consisting of death, myocardial infarction (MI) and target vessel revascularisation (TVR)]. EuroQoL5D (EQ-5D) health survey was used to measure quality of life at baseline and six-months post PCI. Cost per quality-adjusted life-year (QALY) gained and cost per TVR and MACE avoided were calculated to assess the costeffectiveness of DES. Costs are expressed in US dollars (1USD = 7.7HKD). Results: DES was implanted in 61.8% (n = 139) and BMS in 38.2% (n = 86) of patients. Patients who received DES compared to BMS were more likely to be female and present with acute coronary syndrome (p < 0.01). There were no significant differences in six-month mortality (1.4 vs. 4.7%, p = 0.15), TVR (2.2 vs. 4.7%, p = 0.30), MI
ABSTRACTS
Heart, Lung and Circulation 2011;20S:S1–S155
S30
Abstracts CSANZ Abstracts 2011
ABSTRACTS
(1.4 vs. 2.3%, p = 0.63) or MACE (4.3 vs. 10.5%, p = 0.07) in patients who received DES vs. BMS, respectively. Incremental cost-effectiveness ratio was $163,058/QALY gained and $130,447/TVR and $52,599/MACE avoided. Conclusion: In this registry, DES was not a cost-effective strategy in large coronary vessels (≥3.5 mm) compared with BMS in terms of QALY gained and adverse events avoided. doi:10.1016/j.hlc.2011.05.075 73 D-Dimer and the Risk of Cardiovascular Disease: The Framingham Heart Study E. Shaw 1,∗ , J. Massaro 2 , D. Levy 3 , C. O’Donnell 3 , R. D’Agostino 2 , G. Tofler 1 1 The
Royal North Shore Hospital, Sydney, Australia University, Boston, USA 3 The Framingham Heart Study of the National Heart, Lung, and Blood Institute of the National Institutes of Health, Boston, USA 2 Boston
Background: Abnormalities in haemostasis play an important role in the pathophysiology of cardiovascular disease (CVD). D-Dimer, the primary degradation product of cross-linked fibrin, is an important haemostasis marker that reflects ongoing thrombus formation and lysis. An elevated D-Dimer level indicates recent or ongoing intravascular blood coagulation and is seen in several thrombotic disorders. We investigated the association between D-Dimer levels and CVD risk among individuals without prior CVD after accounting for other risk factors. Methods: D-Dimer levels were measured in 3267 participants without prior CVD in the Framingham Heart Study offspring cohort, at a routine clinic visit between 1991 and 1995. The average follow up of participants was 10 years. D-Dimer levels were measured using an ELISA technique. Results: D-Dimer levels had a strong unadjusted linear relation with incident CVD (p < 0.001). After adjustment for age, sex, systolic blood pressure, diabetes mellitus, glucose level, cigarette smoking, antihypertensive therapy, body mass index, total cholesterol, HDL cholesterol and triglycerides, the relative risk of CVD for individuals in the highest quartile of D-Dimer, as compared with those in the lowest quartile, was 1.66 (p value = 0.041). Conclusion: D-Dimer levels are predictive of CVD after accounting for established risk factors. These findings support the importance of intravascular thrombosis and fibrinolysis as determinants of CVD risk. doi:10.1016/j.hlc.2011.05.076
Heart, Lung and Circulation 2011;20S:S1–S155
74 Diabetes has a Greater Association with Recurrent versus Incident Hospitalised Acute Coronary Syndromes L. Nedkoff 1,∗ , T. Briffa 1 , J. Hung 2 , P. Thompson 2 , M. Knuiman 1 1 School of Population Health, University of Western Australia, Australia 2 School of Medicine and Pharmacology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
Background: We examined diabetes as a comorbidity in hospitalised acute coronary syndromes (ACS) to determine whether there was a differing association with incident and recurrent events. Methods: The Western Australian Data Linkage System was used to identify ACS events in 35–84 year olds from 1996 to 2007. Incident events were those with a 10-year history free of coronary heart disease (CHD). Diabetes status was determined using a five year lookback period. Logistic regression was used to calculate age-adjusted and agespecific trends and risk-adjusted odds ratios comparing diabetes in incident and recurrent ACS. Results: There were 29,421 incident (men 66.6%) and 35,489 recurrent (men 64.6%) ACS events identified. The proportion of incident ACS patients presenting with diabetes was 18.2% in men and 22.5% in women, and 30.7% and 36.7% respectively for recurrent admissions. There was a greater annual increase in the proportion of recurrent ACS admissions with diabetes (men 6.8%/year (95% CI 5.9, 7.7%); women 6.5%/year (95% CI 5.3, 7.6%)) compared with incident ACS (men 3.0%/year (95% CI 2.0, 4.1%); women 2.8%/year (95% CI 1.4, 4.2%)). In 2007, the likelihood of presenting with comorbid diabetes in a recurrent versus incident ACS admission was 1.6 times higher in men (95% CI 1.3, 1.8) and 1.7 times higher in women (95% CI 1.3, 2.1). This difference was apparent across all age groups. Conclusion: The proportion of hospitalised ACS events with diabetes increased significantly from 1996 to 2007. This increase was greater in recurrent than incident events in all age groups, which has important implications for secondary prevention efforts. doi:10.1016/j.hlc.2011.05.077 75 Effect of Atherosclerotic Risk Factors on Microcirculatory Resistance: A Further Obesity Paradox J. Layland 1,2,∗ , A. MacIsaac 1,2 , S. Bappayya 2 , J. 1,2 1,2 1,2 Somaratne , R. Whitbourn , A. Wilson 1 Department 2 University
of Cardiology, St Vincent’s Hospital, Australia of Melbourne, Australia
Purpose: There is little data on the impact of obesity and other established atherosclerotic risk factors on measured microvascular resistance. We aimed to assess the relationship between atherosclerotic risk factors and microvascular resistance.
S29
infusions (IC dextrose) were performed in four patients (21 segments). Macrovascular response [% change segmental lumen volume (SLV)] and plaque burden [percent atheroma volume (PAV)] were studied in 5-mm coronary segments. Microvascular response [percent change in coronary blood flow (CBF)], was calculated following each infusion. Results: IC salbutamol demonstrated significant doseresponse SLV and CBF from baseline respectively (0.15 g/min: 3.5 ± 1.3%, 28 ± 14%, p = 0.04, p = NS; 0.30 g/min: 5.5 ± 1.4%, 54 ± 17%, p = 0.001, p < 0.0001; 0.60 g/min: 4.8 ± 1.6%, 66 ± 15%, p = 0.02, p < 0.0001), with SLV responses further exemplified in low versus high plaque burden groups. Salbutamol vasomotor responses were abolished by L-NMMA, supporting nitric oxidedependent mechanisms. Vehicle infusions resulted in no significant SLV or CBF. Multivariate analysis including conventional cardiovascular risk factors, PAV, segmental remodeling and plaque eccentricity indices identified PAV as the only significant predictor of a SLV to IC salbutamol (coefficient −0.18, 95% CI −0.32 to −0.044, p = 0.015). Conclusions: Intracoronary salbutamol is a novel endothelium-dependent epicardial and microvascular coronary vasodilator. IVUS-derived plaque burden is a major determinant of focal coronary endothelial function.
cant relationship between IMR and CR, described by: IMR = (0.0023 × CR + 0.06)−1 r = 0.73, p < 0.001. A ≥5% relative increase in CR identified an IMR of <16 with 100% sensitivity and 100% specificity (AUC = 1.0); and an IMR of <25 with 100% sensitivity and 75% specificity (AUC = 0.90).
doi:10.1016/j.hlc.2011.05.073
doi:10.1016/j.hlc.2011.05.074
71 Coronary Endothelial Function by the Index of Microcirculatory Resistance can be Estimated by Evaluating Left Ventricular Contractile Reserve at Low Dose Dobutamine Echocardiography
72 Cost-Effectiveness of Drug-Eluting Stents in Large (≥3.5 mm) Coronary Arteries
M. Leung ∗ , S. Lo, C. Juergens, D. Leung Liverpool Hospital, Sydney, Australia Coronary endothelial function has important diagnostic and prognostic implications but its routine assessment is difficult. The index of microcirculatory resistance (IMR) is considered a reliable but invasive measure. We hypothesised that left ventricular (LV) contractile reserve (CR) measured with strain imaging at low dose dobutamine echocardiography (echo) is a reliable non-invasive surrogate of IMR in patients without significant epicardial disease. Methods: Twenty-two patients (15 men, aged 59 ± 8 years, 15 DM, mean ejection fraction 65%, range 31–81%, none had significant epicardial coronary disease by fractional flow reserve) underwent low dose dobutamine echo and invasive coronary angiography. Global mean peak systolic longitudinal strain was measured in the three apical views at rest and low dose dobutamine echo with CR defined as the difference between the resting and low dose values. IMR was measured in the left anterior descending artery at angiography. Results: The mean IMR was 19.34 (range 7–104) and mean peak global systolic strain at rest was −17.56% and at low dose −19.02 corresponding to a mean CR of +1.45% (9% relative increase). There was a signifi-
Conclusions: LV CR measured with strain imaging at low dose dobutamine echo may be used to estimate IMR as a measure of coronary microvascular function in patients without significant coronary artery disease.
B. Yan 1,∗ , M. Liu 1 , V. Lee 1 , C. Reid 2 , C. Yu 1 1 Chinese 2 Monash
University of Hong Kong, Hong Kong University, Melbourne, Australia
Background: Percutaneous coronary intervention (PCI) with bare-metal stent (BMS) implantation in large coronary vessels (≥3.5 mm) is associated with low risk of restenosis that is comparable to drug-eluting stents (DES). We aim to assess the cost-effectiveness of DES compared to BMS in large coronary vessels. Methods: We analysed 225 consecutive patients undergoing PCI with ≥3.5 mm stent at our institution from September 2009 to July 2010. Clinical outcomes were measured by the occurrence of major adverse cardiac events [MACE, consisting of death, myocardial infarction (MI) and target vessel revascularisation (TVR)]. EuroQoL5D (EQ-5D) health survey was used to measure quality of life at baseline and six-months post PCI. Cost per quality-adjusted life-year (QALY) gained and cost per TVR and MACE avoided were calculated to assess the costeffectiveness of DES. Costs are expressed in US dollars (1USD = 7.7HKD). Results: DES was implanted in 61.8% (n = 139) and BMS in 38.2% (n = 86) of patients. Patients who received DES compared to BMS were more likely to be female and present with acute coronary syndrome (p < 0.01). There were no significant differences in six-month mortality (1.4 vs. 4.7%, p = 0.15), TVR (2.2 vs. 4.7%, p = 0.30), MI
ABSTRACTS
Heart, Lung and Circulation 2011;20S:S1–S155
S30
Abstracts CSANZ Abstracts 2011
ABSTRACTS
(1.4 vs. 2.3%, p = 0.63) or MACE (4.3 vs. 10.5%, p = 0.07) in patients who received DES vs. BMS, respectively. Incremental cost-effectiveness ratio was $163,058/QALY gained and $130,447/TVR and $52,599/MACE avoided. Conclusion: In this registry, DES was not a cost-effective strategy in large coronary vessels (≥3.5 mm) compared with BMS in terms of QALY gained and adverse events avoided. doi:10.1016/j.hlc.2011.05.075 73 D-Dimer and the Risk of Cardiovascular Disease: The Framingham Heart Study E. Shaw 1,∗ , J. Massaro 2 , D. Levy 3 , C. O’Donnell 3 , R. D’Agostino 2 , G. Tofler 1 1 The
Royal North Shore Hospital, Sydney, Australia University, Boston, USA 3 The Framingham Heart Study of the National Heart, Lung, and Blood Institute of the National Institutes of Health, Boston, USA 2 Boston
Background: Abnormalities in haemostasis play an important role in the pathophysiology of cardiovascular disease (CVD). D-Dimer, the primary degradation product of cross-linked fibrin, is an important haemostasis marker that reflects ongoing thrombus formation and lysis. An elevated D-Dimer level indicates recent or ongoing intravascular blood coagulation and is seen in several thrombotic disorders. We investigated the association between D-Dimer levels and CVD risk among individuals without prior CVD after accounting for other risk factors. Methods: D-Dimer levels were measured in 3267 participants without prior CVD in the Framingham Heart Study offspring cohort, at a routine clinic visit between 1991 and 1995. The average follow up of participants was 10 years. D-Dimer levels were measured using an ELISA technique. Results: D-Dimer levels had a strong unadjusted linear relation with incident CVD (p < 0.001). After adjustment for age, sex, systolic blood pressure, diabetes mellitus, glucose level, cigarette smoking, antihypertensive therapy, body mass index, total cholesterol, HDL cholesterol and triglycerides, the relative risk of CVD for individuals in the highest quartile of D-Dimer, as compared with those in the lowest quartile, was 1.66 (p value = 0.041). Conclusion: D-Dimer levels are predictive of CVD after accounting for established risk factors. These findings support the importance of intravascular thrombosis and fibrinolysis as determinants of CVD risk. doi:10.1016/j.hlc.2011.05.076
Heart, Lung and Circulation 2011;20S:S1–S155
74 Diabetes has a Greater Association with Recurrent versus Incident Hospitalised Acute Coronary Syndromes L. Nedkoff 1,∗ , T. Briffa 1 , J. Hung 2 , P. Thompson 2 , M. Knuiman 1 1 School of Population Health, University of Western Australia, Australia 2 School of Medicine and Pharmacology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
Background: We examined diabetes as a comorbidity in hospitalised acute coronary syndromes (ACS) to determine whether there was a differing association with incident and recurrent events. Methods: The Western Australian Data Linkage System was used to identify ACS events in 35–84 year olds from 1996 to 2007. Incident events were those with a 10-year history free of coronary heart disease (CHD). Diabetes status was determined using a five year lookback period. Logistic regression was used to calculate age-adjusted and agespecific trends and risk-adjusted odds ratios comparing diabetes in incident and recurrent ACS. Results: There were 29,421 incident (men 66.6%) and 35,489 recurrent (men 64.6%) ACS events identified. The proportion of incident ACS patients presenting with diabetes was 18.2% in men and 22.5% in women, and 30.7% and 36.7% respectively for recurrent admissions. There was a greater annual increase in the proportion of recurrent ACS admissions with diabetes (men 6.8%/year (95% CI 5.9, 7.7%); women 6.5%/year (95% CI 5.3, 7.6%)) compared with incident ACS (men 3.0%/year (95% CI 2.0, 4.1%); women 2.8%/year (95% CI 1.4, 4.2%)). In 2007, the likelihood of presenting with comorbid diabetes in a recurrent versus incident ACS admission was 1.6 times higher in men (95% CI 1.3, 1.8) and 1.7 times higher in women (95% CI 1.3, 2.1). This difference was apparent across all age groups. Conclusion: The proportion of hospitalised ACS events with diabetes increased significantly from 1996 to 2007. This increase was greater in recurrent than incident events in all age groups, which has important implications for secondary prevention efforts. doi:10.1016/j.hlc.2011.05.077 75 Effect of Atherosclerotic Risk Factors on Microcirculatory Resistance: A Further Obesity Paradox J. Layland 1,2,∗ , A. MacIsaac 1,2 , S. Bappayya 2 , J. 1,2 1,2 1,2 Somaratne , R. Whitbourn , A. Wilson 1 Department 2 University
of Cardiology, St Vincent’s Hospital, Australia of Melbourne, Australia
Purpose: There is little data on the impact of obesity and other established atherosclerotic risk factors on measured microvascular resistance. We aimed to assess the relationship between atherosclerotic risk factors and microvascular resistance.