I R Starkey

Western General Hospital, Edinburgh, Scotland, United Kingdom

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Publications (52)450.86 Total impact

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    ABSTRACT: The optimal strategy for treating coronary bifurcation lesions remains a subject of debate. With bare-metal stents, single-stent approaches appear to be superior to systematic 2-stent strategies. Drug-eluting stents, however, have low rates of restenosis and might offer improved outcomes with complex stenting techniques. Patients with significant coronary bifurcation lesions were randomized to either a simple or complex stenting strategy with drug-eluting stents. In the simple strategy, the main vessel was stented, followed by optional kissing balloon dilatation/T-stent. In the complex strategy, both vessels were systematically stented (culotte or crush techniques) with mandatory kissing balloon dilatation. Five hundred patients 64+/-10 years old were randomized; 77% were male. Eighty-two percent of lesions were true bifurcations (>50% narrowing in both vessels). In the simple group (n=250), 66 patients (26%) had kissing balloons in addition to main-vessel stenting, and 7 (3%) had T stenting. In the complex group (n=250), 89% of culotte (n=75) and 72% of crush (n=169) cases were completed successfully with final kissing balloon inflations. The primary end point (a composite at 9 months of death, myocardial infarction, and target-vessel failure) occurred in 8.0% of the simple group versus 15.2% of the complex group (hazard ratio 2.02, 95% confidence interval 1.17 to 3.47, P=0.009). Myocardial infarction occurred in 3.6% versus 11.2%, respectively (P=0.001), and in-hospital major adverse cardiovascular events occurred in 2.0% versus 8.0% (P=0.002), respectively. Procedure duration and x-ray dose favored the simple approach. When coronary bifurcation lesions are treated, a systematic 2-stent technique results in higher rates of in-hospital and 9-month major adverse cardiovascular events. This difference is largely driven by periprocedural myocardial infarction. Procedure duration is longer, and x-ray dose is higher. The provisional technique should remain the preferred strategy in the majority of cases. Clinical Trial Registration Information- URL: http://www.clinicaltrials.gov. Unique identifier: NCT 00351260.
    Circulation 03/2010; 121(10):1235-43. DOI:10.1161/CIRCULATIONAHA.109.888297 · 14.95 Impact Factor
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    ABSTRACT: The US Food and Drug Administration recently concluded that data on off-label drug-eluting stent (DES) safety are limited. However, in actual clinical practice, DES are often used for off-label indications, and observational studies demonstrate that complications are higher when compared with on-label use. We aimed to determine whether clinical outcomes differ after DES and bare-metal stent implantation in a patient cohort defined by DES off-label indications. We used the national revascularization registry in Scotland to identify patients who underwent coronary stenting for an off-label indication between January 2003 and September 2005. Individual-level linkage to comprehensive national admission and death databases was used to ascertain the end points of death, myocardial infarction, and target-vessel revascularization. We calculated propensity scores on the basis of clinical, demographic, and angiographic variables and matched DES to bare-metal stents on a 1:1 basis. The final study population consisted of 1642 patients, well matched for important covariables at baseline. Event-free survival was calculated over 24 months with the Kaplan-Meier method. All-cause death was more common after bare-metal stent implantation during follow-up (7.7% versus 6.6%; hazard ratio 0.63; 95% confidence interval, 0.40 to 0.99; P=0.04). No difference in the rates of myocardial infarction were noted (7.3% versus 7.5%; hazard ratio 1.02; 95% confidence interval, 0.69 to 1.54; P=0.92). Target-vessel revascularization was reduced in patients treated with DES (13.9% versus 10.7%; hazard ratio 0.67; 95% confidence interval, 0.49 to 0.93; P=0.02). At 24 months, patients treated with DES for off-label indications had lower rates of death and target-vessel revascularization and similar rates of myocardial infarction, as compared with patients treated with bare-metal stents.
    Circulation Cardiovascular Interventions 08/2008; 1(1):45-52. DOI:10.1161/CIRCINTERVENTIONS.108.769042 · 6.54 Impact Factor
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    ABSTRACT: To determine whether drug-eluting stent (DES) use varies among Scottish hospitals, and the extent to which any variations are explained by differences between operators, patients and lesions. Multi-level analysis of consecutive patients treated with percutaneous coronary intervention (PCI) between April 2005 and March 2006 in Scotland, using the Scottish Coronary Revascularization Registry. A total of 38 operators performed 5967 PCI procedures on 8489 lesions. Crude level of DES use was 47.6%, and the results varied among hospitals (range 30.6-61.8%, chi(2) = 341.6, P < 0.0001). There was significant between-operator variation in the null model. This was attenuated by the addition of hospital as a fixed effect. Nonetheless, the final model demonstrated significant between-operator variability [sigma(2) = 0.486 (0.249-0.971)] and between-hospital variation, after case-mix adjustment. Within Scotland, marked variation existed among hospitals in the use of DES. Operator was the most important factor at patient level, and hospital of treatment, rather than case-mix, was the most important modifier of between-operator variation. Patient selection for DES is complex and may contribute to much of the variations demonstrated. Consensus criteria would provide more detail than is included in current guidance, may aid decision-making for individual patients, reduce opportunity costs and ensure equity of access.
    Journal of Public Health 06/2008; 30(2):186-93. DOI:10.1093/pubmed/fdn016 · 2.06 Impact Factor
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    ABSTRACT: This prospective observational study aimed to assess the impact of employment status and deprivation on quality of life 12 months after percutaneous coronary intervention (PCI). Patients completed a questionnaire at baseline and at 1 year follow-up including a health utility score (EQ-5D), symptoms and employment status. Deprivation was assessed using the Carstairs' deprivation category based on area postcodes. The majority (79.6%) of patients of working age returned to work within 12 months. Unemployment was associated with a lower quality of life (QoL) at baseline (0.49 (0.32) vs 0.61 (0.27), p=0.002) and less improvement in QoL 1 year after PCI (0.15 (0.37) vs 0.26 (0.31), p<0.012). Furthermore, unemployed patients had significantly less improvement in chest pain score (p=0.002) and breathlessness (p<0.001). Unemployed patients from the most deprived areas had lowest QoL at follow-up and least improvement in QoL at 1 year. Unemployment and deprivation are associated with poorer outcomes following PCI.
    International journal of cardiology 12/2007; 122(2):168-9. DOI:10.1016/j.ijcard.2006.11.052 · 6.18 Impact Factor
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    ABSTRACT: The aim of this study was to compare clinical outcomes for transradial and transfemoral percutaneous coronary intervention in patients with ST-segment elevation myocardial infarction undergoing rescue angioplasty. Transfemoral percutaneous coronary intervention in patients with acute myocardial infarction treated with systemic thrombolysis is associated with a significant risk of vascular complications. A transradial approach may reduce vascular complications, improve mobilization and facilitate earlier discharge. In a retrospective analysis, clinical outcomes for 287 consecutive patients undergoing rescue angioplasty for acute myocardial infarction were determined. Data were recorded using a standardized proforma and analyzed using SPSS. Procedural success was similar for the transradial and transfemoral routes (98% vs. 93%; P = 0.3). There was a reduction in vascular complications (0 (0%) vs. 32 (13%); P < 0.01) and post-procedural length of stay (7.0 +/- 7.9 vs. 7.9 +/- 5.6 days; P < 0.005) in the radial group when compared with the femoral group. There were no differences in procedural or in-hospital mortality, procedure duration, or radiation dose between the two groups. Rescue angioplasty performed via the radial artery is safe, effective, and associated with a reduction in vascular complications and length of hospital stay when compared with the femoral approach. These findings suggest that where facilities and experience allow rescue angioplasty in patients with acute myocardial infarction should be performed via the radial artery.
    Catheterization and Cardiovascular Interventions 11/2007; 70(5):670-5. DOI:10.1002/ccd.21182 · 2.51 Impact Factor
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    European Heart Journal 06/2007; 28(9):1071. DOI:10.1093/eurheartj/ehl370 · 14.72 Impact Factor
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    ABSTRACT: To assess the effect of changing clinical practice on the costs and outcomes of percutaneous coronary intervention (PCI) between 1998 and 2002. Two tertiary interventional centres. Consecutive patients undergoing PCI over a 12-month period between 1998 and 2002. Comparative observational study of costs and 12-month clinical outcomes of consecutive PCI procedures in 1998 (n = 1047) and 2002 (n = 1346). Clinical data were recorded in the Scottish PCI register. Repeat PCI, coronary artery bypass graft and mortality were obtained by record linkage. Costs of equipment were calculated using a computerised bar-code system and standard National Health Service reference costs. Between 1998 and 2002, the use of bare metal stents increased from 44% to 81%, and the use of glycoprotein IIB/IIIA inhibitors increased from 0% to 14% of cases. During this time, a significant reduction was observed in repeat target-vessel PCI (from 8.4% to 5.1%, p = 0.001), any repeat PCI (from 11.7% to 9.2%, p = 0.05) and any repeat revascularisation (from 15.1% to 11.3%, p = 0.009) within 12 months. Significantly higher cost per case in 2002 compared with 1998 (mean (standard deviation) 2311 pounds (1158) v 1785 pounds (907), p<0.001) was mainly due to increased contribution from bed-day costs in 2002 (45.0% (16.3%) v 26.2% (12.6%), p = 0.01) associated with non-elective cases spending significantly longer in hospital (6.22 (4.3) v 4.6 (4.3) days, p = 0.01). Greater use of stents and glycoprotein IIb/IIIa inhibitors between 1998 and 2002 has been accompanied by a marked reduction in the need for repeat revascularisation. Longer duration of hospital stay for non-elective cases is mainly responsible for increasing costs. Strategies to reduce the length of stay could considerably reduce the costs of PCI.
    Heart (British Cardiac Society) 02/2007; 93(2):195-9. DOI:10.1136/hrt.2006.090134 · 6.02 Impact Factor
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    ABSTRACT: To determine whether socioeconomic status (SES) influences clinical outcomes and quality of life after percutaneous coronary intervention (PCI). Prospective observational study. Two interventional cardiac centres. 1346 consecutive patients undergoing PCI over a 12-month period. Outcomes: Self reported health-related quality of life (HRQoL; EuroQol-5 Dimensions (EQ-5D); EuroQol Visual Analogue Scale (EQ-VAS)), repeat angiography, revascularisation, hospital admission, myocardial infarction and death within 12 months, by SES derived using postal address code. No significant differences were found between patients with high and low SES in the occurrence of repeat angiography (p = 0.55), repeat revascularisation (PCI, p = 0.81, CAEG, p = 0.27), total cardiac hospitalisation (p = 0.10), myocardial infarction (p = 0.97) or death 12 months after PCI (p = 0.88). Non-procedure-related readmissions were higher in patients with low SES (18.6% v 13.7%; p = 0.025). After adjustment for confounding factors, patients with low SES had lower HRQoL scores at baseline (95% CI for difference 0.01 to 0.14; p = 0.003) and at 12 months (95% CI 0.07 to 0.17; p<0.001) compared with those with high SES. Clinical outcomes were similar for patients in different SES groups. Patients with low SES had considerably more non-procedure-related readmissions and lower quality-of-life scores. Future studies on HRQoL after coronary revascularisation should take account of these important differences related to SES.
    Journal of Epidemiology &amp Community Health 12/2006; 60(12):1085-8. DOI:10.1136/jech.2005.044255 · 3.29 Impact Factor
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    ABSTRACT: To determine whether percutaneous coronary intervention (PCI) hospital volume of throughput is associated with periprocedural and medium-term events, and whether any associations are independent of differences in case mix. Retrospective cohort study of all PCIs undertaken in Scottish National Health Service hospitals over a six-year period. All PCIs in Scotland during 1997-2003 were examined. Linkage to administrative databases identified events over two years' follow up. The risk of events by hospital volume at 30 days and two years was compared by using logistic regression and Cox proportional hazards models. Of the 17,417 PCIs, 4900 (28%) were in low-volume hospitals and 3242 (19%) in high-volume hospitals. After adjustment for case mix, there were no significant differences in risk of death or myocardial infarction. Patients treated in high-volume hospitals were less likely to require emergency surgery (adjusted odds ratio 0.18, 95% confidence interval (CI) 0.07 to 0.54, p = 0.002). Over two years, patients in high-volume hospitals were less likely to undergo surgery (adjusted hazard ratio 0.52, 95% CI 0.35 to 0.75, p = 0.001), but this was offset by an increased likelihood of further PCI. There was no net difference in coronary revascularisation or in overall events. Death and myocardial infarction were infrequent complications of PCI and did not differ significantly by volume. Emergency surgery was less common in high-volume hospitals. Over two years, patients treated in high-volume centres were as likely to undergo some form of revascularisation but less likely to undergo surgery.
    Heart (British Cardiac Society) 12/2006; 92(11):1667-72. DOI:10.1136/hrt.2005.086736 · 6.02 Impact Factor
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    ABSTRACT: To assess variations in decisions to revascularise patients with coronary heart disease between general cardiologists, interventional cardiologists and cardiac surgeons Six cases of coronary heart disease were presented at an open meeting in a standard format including clinical details which might influence the decision to revascularise. Clinicians (n = 53) were then asked to vote using an anonymous electronic system for one of 5 treatment options: medical, surgical (CABG), percutaneous coronary intervention (PCI) or initially medical proceeding to revascularisation if symptoms dictated. Each case was then discussed in an open forum following which clinicians were asked to revote. Differences in treatment preference were compared by chi squared test and agreement between groups and between voting rounds compared using Kappa. Surgeons were more likely to choose surgery as a form of treatment (p = 0.034) while interventional cardiologists were more likely to choose PCI (p = 0.056). There were no significant differences between non-interventional and interventional cardiologists (p = 0.13) in their choice of treatment. There was poor agreement between all clinicians in the first round of voting (Kappa 0.26) but this improved to a moderate level of agreement after open discussion for the second vote (Kappa 0.44). The level of agreement among surgeons (0.15) was less than that for cardiologists (0.34) in Round 1, but was similar in Round 2 (0.45 and 0.45 respectively). In this case series, there was poor agreement between cardiac clinical specialists in the choice of treatment offered to patients. Open discussion appeared to improve agreement. These results would support the need for decisions to revascularise to be made by a multidisciplinary panel.
    Journal of Cardiothoracic Surgery 02/2006; 1:2. DOI:10.1186/1749-8090-1-2 · 1.02 Impact Factor
    This article is viewable in ResearchGate's enriched format
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    ABSTRACT: Triptans are contraindicated in patients with known or suspected coronary artery disease (CAD); however, few studies have evaluated triptans in patients with obstructive CAD to quantify the vasoconstrictive effect on diseased coronary vessels. Patients undergoing percutaneous transluminal coronary angioplasty for symptomatic single-vessel CAD were randomised to one of three parallel cohorts to receive (1) 6 mg intravenously (IV) infused eletriptan plus subcutaneous (SC) placebo, (2) IV infused placebo plus 6 mg SC sumatriptan or (3) IV infused placebo plus SC placebo, as simultaneous administrations in a double-blind manner. Serial arteriograms, hemodynamic indices, electrocardiography and triptan plasma concentrations were obtained. . Fifteen minutes after triptan challenge, median (95% confidence interval) changes in coronary artery diameter (CADM) at the focal point of the stenosed segment were: dilation of 2.6% (-5.0, 11.4), eletriptan 6 mg IV (n = 18); constriction of 6.8% (-12.6, 0.4), sumatriptan 6 mg SC (n = 17), and constriction of 4.5% (-7.0, 7.9), placebo (n = 10). One patient had angiographic evidence of a new thrombus at the stenosis site, necessitating termination of study infusion and successful stenting of the lesion. There was no correlation between effects on CADM and triptan concentration, or between hemodynamic or electrocardiograph changes and the presence (n = 13) or absence (n = 33) of chest pain. Triptans had very little effect on diseased epicardial coronary arteries in a small group of angina sufferers with established CAD. Results should be interpreted cautiously since there may be instances where even modest triptan-associated epicardial constriction is sufficient to precipitate myocardial ischemia in patients with severe obstructive CAD.
    European Journal of Clinical Pharmacology 12/2005; 61(10):733-42. DOI:10.1007/s00228-005-0988-4 · 2.70 Impact Factor
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    ABSTRACT: To assess the effect of long-acting local anesthetic (levobupivacaine) in addition to lidocaine for the management of femoral artery sheaths during and after percutaneous coronary intervention (PCI). Femoral artery sheaths are commonly used during PCI. Sheath removal is often delayed after the procedure by which time short-acting local anesthetic agents may no longer be effective. Sixty patients were randomized to either usual care or the administration of local levobupivacaine after PCI. Patients were asked to report their pain experienced on a visual analogue score. Thirty patients received additional levobupivacaine (0.5%) and 30 received standard care. There were no procedural differences between the groups, except that more patients in the control group received intravenous (IV) morphine at the time of sheath removal. There was no difference between the control group and levobupivacaine group in pain scores at the time of sheath insertion. (2.0 +/- 0.4 versus 1.8 +/- 0.3; p = 0.80). Both groups recorded low pain scores while waiting for sheath removal, and the score was slightly (but not significantly) lower in the levobupivacaine group (1.3 +/- 0.2 versus 0.8 +/- 0.2; p = 0.09). Pain scores were lower in the levobupivacaine group during sheath removal 2.2 +/- 0.4 versus 1.1 +/- 0.2; p = 0.02). There were no differences in terms of blood pressure between the groups at any time point. Levobupivacaine reduced the need for IV opiate and provided better analgesia than lidocaine alone in patients undergoing PCI.
    The Journal of invasive cardiology 09/2005; 17(8):406-8. · 0.82 Impact Factor
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    ABSTRACT: To determine whether mortality following percutaneous coronary intervention vs. coronary bypass grafting varies according to whether or not patients have diabetes. We used the Scottish Coronary Revascularization Register to identify all patients undergoing revascularization in Scottish NHS hospitals since 1997. We excluded single-vessel disease, left main stem stenosis, and bypass grafting performed at the same time as other operations. We used death certificate data from the Registrar General to identify all subsequent deaths. Of the 6320 eligible procedures, 5042 (80%) were bypass grafts and 1278 (20%) angioplasties. Overall 831 (13%) patients had diabetes with no significant difference by procedure (13% vs. 12%). A total of 382 deaths occurred over a mean follow-up of 2.3 years. Diabetic patients had a poorer prognosis following both surgery (adjusted hazards ratio (HR) 1.43, 95% confidence interval (CI) 1.08, 1.89) and percutaneous intervention (adjusted HR 2.58, 95% CI 1.43, 4.63). Among non-diabetic patients, no significant differences in mortality were detected between the two procedures. Among diabetic patients, no significant difference was detected in those with two-vessel disease. In those with impaired left ventricular function and triple-vessel disease, angioplasty was associated with a significantly higher risk of death (adjusted HR 3.58, 95% CI 1.40, 9.19). This is the first study to demonstrate statistically significant results that support the BARI trial findings. Our study demonstrated a significant difference for triple-vessel disease but not two-vessel disease. The former may be due to incomplete revascularization using percutaneous intervention. Our results require corroboration from randomized trials.
    Diabetic Medicine 08/2004; 21(7):790-2. DOI:10.1111/j.1464-5491.2004.01171.x · 3.06 Impact Factor
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    ABSTRACT: This study compares 12 month clinical outcomes and procedural costs at two interventional centres with significant differences in crude mortality and revascularization outcomes between 1997 and 1998. Percutaneous coronary intervention (PCI) registry data on 1046 consecutive patients treated contemporaneously at two university centres were linked to hospital discharge and death data to provide 12 month follow-up information on survival and repeat revascularization. Costs were determined by detailed analysis of equipment use, length of stay and staff from 100 contemporary cases at each centre to derive a procedural cost model. This model was then applied retrospectively to estimate cost per procedure. Stents were used more frequently at one centre (56 versus 26 per cent, chi(2) test, p < 0.001) resulting in greater procedural cost [mean (SE), pounds sterling 1970 (34) versus pounds sterling 1521 (39), t-test, p < 0.001). One year repeat target vessel PCI was significantly greater at the centre using more stents (10.3 versus 5.6 per cent, chi(2) test, p = 0.005) and the need for any repeat revascularization (PCI or coronary artery by-pass surgery) was also significantly greater at this centre (18.4 versus 10.8 per cent, chi(2) test, p < 0.001). Cox regression revealed that after correction for case-mix the difference in the need for repeat target vessel PCI between the two centres was no longer significant (p = 0.15). In the two centres studied, crude differences in cost per case, mortality and the need for revascularization were largely accounted for by significant differences in case-mix. Comparison of outcomes and costs between centres should not be published without careful adjustment for differences in case-mix.
    Journal of Public Health 06/2004; 26(2):177-84. DOI:10.1093/pubmed/fdh142 · 2.30 Impact Factor
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    S J Leslie, I R Starkey
    Heart (British Cardiac Society) 06/2004; 90(5):562. DOI:10.1136/hrt.2003.025494 · 6.02 Impact Factor
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    ABSTRACT: To determine current outcomes of percutaneous transluminal coronary angioplasty (PTCA) and coronary artery bypass grafting (CABG). The Scottish coronary revascularisation register provided prospectively collected data on case mix and in-hospital complications for all revascularisation procedures between April 1997 and March 1999 (4775 PTCA; 5115 CABG). Linkage to routine hospital discharge and death data provided follow up information on survival and repeat revascularisation. Stents were used in 51% of PTCA procedures. CABG patients were older, had more severe coronary disease, and had greater comorbidity. PTCA was more likely to be undertaken as an urgent or emergency procedure. Perioperative death and urgent surgery followed 0.3% and 0.6% of PTCA procedures, respectively. Case fatality rates were higher following CABG, with 6.7% dead within two years compared with 3.4% following PTCA. PTCA was more often followed by readmission for ischaemic heart disease, repeat angiography, or revascularisation: 22.8% of patients had repeat revascularisation within two years, compared with 1.8% following CABG. The severity of coronary heart disease was greater than in previously published registry studies and randomised trials. Despite this, overall survival figures were comparable and repeat revascularisation rates lower, particularly following PTCA. Perioperative death and urgent surgery following PTCA were also lower. These favourable outcomes may be attributable, in part, to increased use of bail out and elective stenting.
    Heart (British Cardiac Society) 07/2001; 85(6):662-6. · 6.02 Impact Factor
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    ABSTRACT: BACKGROUND: The technique of coronary stenting has evolved over recent years, with improved stent technology and effective antiplatelet therapies to prevent stent thrombosis. In Europe, reductions in stent and equipment costs have resulted from increased market competition. The impact of these changes on the in-hospital procedural cost of percutaneous coronary intervention (PCI) in the current clinical setting is not known. METHODS: We compared the initial equipment and pharmaceutical costs of one hundred consecutive, unselected patients undergoing PCI in 1998 to a similar population who underwent PCI in 1994. RESULTS: Similar patient characteristics were noted, yet more complex disease (multivessel, AHA type B2/C lesions) was treated in the 1998 population. The stent utilization rate (83% vs 15%, p < 0.0001) and use of intravenous and/or oral antiplatelet therapy (abciximab, ticlopidine) (64% vs 4%, p < 0.0001) was higher in 1998. Similar angiographic success was achieved in each group with low complication rates. Mean hospital stay was reduced in the 1998 group (2.6 +/- 2.8 vs 4.3 +/- 3.8 days, p < 0.001). Repeat PCI was required more frequently in the 1994 population (26% vs 9%, p < 0.001). Overall there was no significant difference in the mean equipment cost between the two groups ( pound 1551 vs pound 1422, p=ns). CONCLUSION: Despite the widespread use of coronary stenting and antiplatelet therapies there appears to be no difference in current in-hospital equipment costs for PCI compared to 1994. Improved clinical outcomes in the 1998 population imply that stenting is a cost-effective therapy.
    International Journal of Cardiovascular Interventions 09/2000; 3(3):161-165. DOI:10.1080/14628840050516073
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    B D Prendergast, F Kerr, I R Starkey
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    ABSTRACT: Although intracoronary stenting procedures have been advocated for the successful treatment of myocardial ischaemia associated with myocardial bridging, the physiological rationale for this approach remains unexplored. The case of a 70 year old man with symptoms of cardiac ischaemia associated with a left anterior descending coronary artery bridge is described, where use of an intracoronary stent abolished the angiographic abnormalities and also restituted pronounced abnormalities of coronary fractional flow reserve.
    Heart (British Cardiac Society) 07/2000; 83(6):705-7. DOI:10.1136/heart.83.6.705 · 6.02 Impact Factor
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    ABSTRACT: Diltiazem reduces non-fatal reinfarction and refractory ischaemia after non-Q-wave myocardial infarction, an acute coronary syndrome similar to the incomplete infarction that occurs after successful reperfusion. We postulated that this agent would reduce cardiac events in patients after acute myocardial infarction treated initially with thrombolytic agents-a clinical application previously unexplored with heart-rate-lowering calcium antagonists. A prospective, randomised, double-blind, sequential trial was done in 874 patients with acute myocardial infarction, but without congestive heart failure, who first received thrombolytic agents. Patients received either 300 mg oral diltiazem once daily, or placebo, initiated within 36-96 h of infarct onset, and given for up to 6 months. The trial primary endpoint was the cumulative first event rate of cardiac death, non-fatal reinfarction, or refractory ischaemia. Additional prespecified endpoints included several composites of non-fatal cardiac events (non-fatal reinfarction combined with refractory ischaemia, all recurrent ischaemia, or the need for myocardial revascularisation). The diagnosis of ischaemia, whether refractory or recurrent, and the need for myocardial revascularisation, was always based on objective electrocardiographical evidence of ischaemia, either at rest or on exertion. For the trial primary endpoint, 131 events occurred in the 444 placebo patients and 97 events in the 430 diltiazem patients (hazard ratio 0.79; 95% CI, 0.61-1.02; p=0.07). For non-fatal cardiac events, diltiazem treatment was associated with a relative decrease (0.76; 0.58-1.00) in the combined event rate of non-fatal reinfarction and refractory ischaemia. There was a similar decrease in the composite non-fatal endpoints of non-fatal reinfarction combined with all recurrent ischaemia (0.80; 0.64-1.00) and non-fatal reinfarction combined with the need for myocardial revascularisation (0.67; 0.46-0.96). The need for myocardial revascularisation alone was significantly reduced by 42% (0.61; 0.39-0.96). No major safety issues were encountered. Diltiazem did not reduce the cumulative occurrence of cardiac death, non-fatal reinfarction, or refractory ischaemia during a 6-month follow-up, but did reduce all composite endpoints of non-fatal cardiac events, especially the need for myocardial revascularisation.
    The Lancet 06/2000; 355(9217):1751-6. DOI:10.1016/S0140-6736(00)02262-5 · 39.21 Impact Factor
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    ABSTRACT: To determine whether spectral analysis of unprocessed radiofrequency (RF) signal offers advantages over standard videodensitometric analysis in identifying the morphology of coronary atherosclerotic plaques. 97 regions of interest (ROI) were imaged at 30 MHz from postmortem, pressure perfused (80 mm Hg) coronary arteries in saline baths. RF data were digitised at 250 MHz. Two different sizes of ROI were identified from scan converted images, and relative amplitudes of different frequency components were analysed from raw data. Normalised spectra was used to calculate spectral slope (dB/MHz), y-axis intercept (dB), mean power (dB), and maximum power (dB) over a given bandwidth (17-42 MHz). RF images were constructed and compared with comparative histology derived from microscopy and radiological techniques in three dimensions. Mean power was similar from dense fibrotic tissue and heavy calcium, but spectral slope was steeper in heavy calcium (-0.45 (0.1)) than in dense fibrotic tissue (-0.31 (0.1)), and maximum power was higher for heavy calcium (-7.7 (2.0)) than for dense fibrotic tissue (-10.2 (3.9)). Maximum power was significantly higher in heavy calcium (-7.7 (2.0) dB) and dense fibrotic tissue (-10.2 (3.9) dB) than in microcalcification (-13.9 (3.8) dB). Y-axis intercept was higher in microcalcification (-5.8 (1.1) dB) than in moderately fibrotic tissue (-11.9 (2.0) dB). Moderate and dense fibrotic tissue were discriminated with mean power: moderate -20.2 (1.1) dB, dense -14.7 (3.7) dB; and y-axis intercept: moderate -11.9 (2.0) dB, dense -5.5 (5.4) dB. Different densities of fibrosis, loose, moderate, and dense, were discriminated with both y-axis intercept, spectral slope, and mean power. Lipid could be differentiated from other types of plaque tissue on the basis of spectral slope, lipid -0.17 (0.08). Also y-axis intercept from lipid (-17.6 (3.9)) differed significantly from moderately fibrotic tissue, dense fibrotic tissue, microcalcification, and heavy calcium. No significant differences in any of the measured parameters were seen between the results obtained from small and large ROIs. Frequency based spectral analysis of unprocessed ultrasound signal may lead to accurate identification of atherosclerotic plaque morphology.
    Heart (British Cardiac Society) 06/1998; 79(5):459-67. DOI:10.1136/hrt.79.5.459 · 6.02 Impact Factor

Publication Stats

1k Citations
450.86 Total Impact Points

Institutions

  • 1989–2007
    • Western General Hospital
      Edinburgh, Scotland, United Kingdom
  • 2006
    • The University of Calgary
      • Faculty of Medicine
      Calgary, Alberta, Canada
  • 2004
    • NHS Lothian
      Edinburgh, Scotland, United Kingdom
  • 2001
    • University of Glasgow
      Glasgow, Scotland, United Kingdom
  • 1986
    • Liverpool Hospital
      Liverpool, New South Wales, Australia