Diabetes mellitus: clinical presentation and outcome in men and women with acute coronary syndromes. Data from the Euro Heart Survey ACS.

AIMS: To study clinical presentation, in-hospital course and short-term prognosis in men and women with diabetes mellitus and acute coronary syndromes (ACS). METHODS: Men (n = 6488, 21.2% with diabetes) and 2809 women (28.7% with diabetes) < or = 80 years old, with a discharge diagnosis of ACS were prospectively enrolled in the Euro Heart Survey of ACS. RESULTS: Women with diabetes were more likely to present with ST elevation than non-diabetic women, a difference that became more marked after adjustment for differences in smoking, hypertension, obesity, medication and prior disease [adjusted odds ratio (OR) 1.46 (1.20, 1.78)], whereas there was little difference between diabetic and non-diabetic men [adjusted OR 0.99 (0.86, 1.14)]. In addition, women with diabetes were more likely to develop Q-wave myocardial infarction (MI) than non-diabetic women [adjusted OR 1.61 (1.30, 1.99)], while there was no difference between men with and without diabetes [adjusted OR 0.99 (0.85, 1.15)]. There were significant interactions between sex, diabetes and presenting with ST-elevation ACS (P < 0.001), and Q-wave MI (P < 0.001), respectively. Of the women with diabetes, 7.4% died in hospital, compared with 3.6% of non-diabetic women [adjusted OR 2.13 (1.39, 3.26)], whereas corresponding mortality rates in men with and without diabetes were 4.1% and 3.3%, respectively [OR 1.13 (0.76, 1.67)] (P for diabetes-sex interaction 0.021). CONCLUSION: In women with ACS, diabetes is associated with higher risk of presenting with ST-elevation ACS, developing Q-wave MI, and of in-hospital mortality, whereas in men with ACS diabetes is not significantly associated with increased risk of either. These findings suggest a differential effect of diabetes on the pathophysiology of ACS based on the patient's sex.

Cardiovascular risk factors and clinical presentation in acute coronary syndromes.

OBJECTIVE: To investigate the hypothesis that risk factors may be differently related to severity of acute coronary syndromes (ACS), with ST elevation used as a marker of severe ACS. DESIGN: Cross sectional study of patients with ACS. SETTING: 103 hospitals in 25 countries in Europe and the Mediterranean basin. PATIENTS: 10,253 patients with a discharge diagnosis of ACS in the Euro heart survey of ACS. MAIN OUTCOME MEASURES: Presenting with ST elevation ACS. RESULTS: Patients with ACS who were smokers had an increased risk to present with ST elevation (age adjusted odds ratio (OR) 1.84, 95% confidence interval (CI) 1.67 to 2.02). Hypertension (OR 0.65, 95% CI 0.60 to 0.70) and high body mass index (BMI) (p for trend 0.0005) were associated with less ST elevation ACS. Diabetes mellitus was also associated with less ST elevation, but only among men. Prior disease (infarction, chronic angina, revascularisation) and treatment with aspirin, beta blockers, or statins before admission were also associated with less ST elevation. After adjustment for age, sex, prior disease, and prior medication, smoking was still significantly associated with increased risk of ST elevation (OR 1.53, 95% CI 1.38 to 1.69), whereas hypertension was associated with reduced risk (OR 0.75, 95% CI 0.69 to 0.82). Obesity (BMI > 30 kg/m2 versus < 25 kg/m2) was independently associated with less risk of presenting with ST elevation among women, but not among men. CONCLUSION: Among patients with ACS, presenting with ST elevation is strongly associated with smoking, whereas hypertension and high BMI (in women) are associated with less ST elevation, independently of prior disease and medication.

A prospective survey of the characteristics, treatments and outcomes of patients with acute coronary syndromes in Europe and the Mediterranean basin; the Euro Heart Survey of Acute Coronary Syndromes (Euro Heart Survey ACS).

AIMS: To better delineate the characteristics, treatments, and outcomes of patients with acute coronary syndromes (ACS) in representative countries across Europe and the Mediterranean basin, and to examine adherence to current guidelines. METHODS AND RESULTS: We performed a prospective survey (103 hospitals, 25 countries) of 10484 patients with a discharge diagnosis of acute coronary syndromes. The initial diagnosis was ST elevation ACS in 42.3%, non-ST elevation ACS in 51.2%, and undetermined electrocardiogram ACS in 6.5%. The discharge diagnosis was Q wave myocardial infarction in 32.8%, non-Q wave myocardial infarction in 25.3%, and unstable angina in 41.9%. The use of aspirin, beta-blockers, angiotensin converting enzyme inhibitors, and heparins for patients with ST elevation ACS were 93.0%, 77.8%, 62.1%, and 86.8%, respectively, with corresponding rates of 88.5%, 76.6%, 55.8%, and 83.9% for non-ST elevation ACS patients. Coronary angiography, percutaneous coronary interventions, and coronary bypass surgery were performed in 56.3%, 40.4%, and 3.4% of ST elevation ACS patients, respectively, with corresponding rates of 52.0%, 25.4%, and 5.4% for non-ST elevation ACS patients. Among patients with ST elevation ACS, 55.8% received reperfusion treatment; 35.1% fibrinolytic therapy and 20.7% primary percutaneous coronary interventions. The in-hospital mortality of patients with ST elevation ACS was 7.0%, for non-ST elevation ACS 2.4%, and for undetermined electrocardiogram ACS 11.8%. At 30 days, mortality was 8.4%, 3.5%, and 13.3%, respectively. CONCLUSIONS: This survey demonstrates the discordance between existing guidelines for ACS and current practice across a broad region in Europe and the Mediterranean basin and more extensively reflects the outcomes of ACS in real practice in this region.

Lack of progress in cardiogenic shock: lessons from the GUSTO trials.

AIMS: We used the GUSTO-I and GUSTO-III databases to evaluate our performance in treating cardiogenic shock patients over much of the 1990s. METHODS AND RESULTS: GUSTO-I (1990-1993) and GUSTO-III (1995-1997) prospectively identified all patients with cardiogenic shock complicating acute myocardial infarction. Demographics, clinical presentation and outcomes for cardiogenic shock patients in the two trials were compared. Only patients enrolled with cardiogenic shock in countries common to both trials were included in these analysis. The 695 patients with cardiogenic shock in GUSTO-III were compared with the 2814 patients with cardiogenic shock in GUSTO-I. GUSTO-III patients were older (P=0.0001) and more likely to be diabetic (P=0.009) and hypertensive (P=0.025). They had a higher Killip class (P=0.002) and significantly greater index anterior infarction than cardiogenic shock patients enrolled in GUSTO-I. Time to treatment, presentation heart rate, and diastolic blood pressure were similar; however, systolic blood pressure at presentation was higher among GUSTO-III patients (P=0.002). Rates of coronary angiography, pulmonary artery catheterization, and mechanical ventilation declined in GUSTO-III compared with GUSTO-I (P=0.001); rates of angioplasty and bypass surgery were similar. Cardiogenic shock mortality in GUSTO-III was significantly higher than in GUSTO-I (62 vs 54%, P=0.001), as were rates of reinfarction (14 vs 11%, P=0.013) and recurrent ischaemia (35 vs 27%, P=0.00001). Mortality at non-U.S. sites (68 and 64%) was higher than at U.S. sites (53 and 50%) in both GUSTO-I and GUSTO-III studies, respectively. Angioplasty, bypass surgery, and balloon pump rates were lower for non-U.S. patients. CONCLUSIONS: Cardiogenic shock continues to be associated with high mortality in thrombolytic-treated patients. Lower mortality observed in the U.S.A. supports consideration for percutaneous and surgical revascularization.

Microparticle-containing oncotic solutions augment in-vitro clot disruption by ultrasound.

Echocardiographic contrast agents enhance blood clot disruption by ultrasound. It has been suggested that the microbubbles add nuclei for the enhancement of cavitation by ultrasound. However, microbubbles are rapidly destroyed by the ultrasound energy. We assessed whether non-gas filled colloidal solutions (hyperoncotic medium molecular hydroxyethyl starch and degraded gelatin polypeptides) will facilitate clot disruption by ultrasound. In two separate experiments human blood clots, 200-400 mg in weight, were weighed and then immersed for 15 seconds in 10 ml normal saline solution containing 0%, 0.1%, 1%, 2%, and 5% of hyperoncotic medium molecular hydroxyethyl starch or 0%, 0.035%, 0.175%, 0.35%, and 0.7% degraded gelatin polypeptides. Clots were randomized to 10 seconds 20 kHz ultrasound or immersion without ultrasound. After treatment, the clots were reweighed, and the percent difference in weight was calculated. Non-gas filled microparticle-containing solutions such as hyperoncotic medium molecular hydroxyethyl starch and degraded gelatin polypeptides significantly augmented blood clot disruption by ultrasound. The effect is dependent on the colloidal solution concentration with maximal effect achieved with 1% hyperoncotic medium molecular hydroxyethyl starch and 0.35% degraded gelatin polypeptides.

Reduced thrombus burden with abciximab delivered locally before percutaneous intervention in saphenous vein grafts.

BACKGROUND: Existing thrombus can complicate percutaneous saphenous vein graft (SVG) intervention. Local delivery of thrombolytics has been used to reduce the thrombus burden often associated with these interventions. We sought to determine whether local delivery of a platelet glycoprotein IIb/IIIa inhibitor is feasible and can reduce thrombus burden before percutaneous SVG intervention. METHODS: We performed a multicenter pilot study of abciximab (0.25 mg/kg) given by local delivery catheter before percutaneous intervention for de novo SVG stenoses followed by intravenous infusion. All patients (n = 58) had >/=60% stenosis and Thrombolysis In Myocardial Infarction (TIMI) grade >0 flow in an SVG of 3 to 4 mm in diameter. Percent diameter stenosis, TIMI thrombus grade, and TIMI flow grade were measured before and after delivery of abciximab and after intervention. RESULTS: Median percent diameter stenosis improved from 69% to 45% (P =.0001) after local delivery, and TIMI thrombus grade >/=1 incidence reduced from 68% to 34% (P =.0001). TIMI flow grade was not significantly affected (P =.12). All patients had a successful intervention (

Age and outcome after acute coronary syndromes without persistent ST-segment elevation.

BACKGROUND: Although age is the most important variable associated with death among patients with persistent ST-segment elevation, its impact on outcome among patients without persistent ST-segment elevation remains unknown. Moreover, the impact of age on the efficacy of antiplatelet therapy with eptifibatide is unknown. METHODS: We analyzed the impact of increased age on outcome (death or [re]infarction) among patients enrolled in PURSUIT (Platelet Glycoprotein IIb/IIIa in Unstable Angina Receptor Suppression Using Integrilin Therapy), a prospective, randomized study comparing placebo versus eptifibatide therapy in acute coronary syndromes without persistent ST-segment elevation. The 9461 patients were divided into 10-year age groups: <50, 50-59, 60-69, 70-79, and >/=80. In addition, we examined whether age had an impact on the efficacy of eptifibatide therapy. RESULTS: Eptifibatide improved outcome at 30 days (P =.04). There was no interaction among age and treatment (placebo vs eptifibatide) and adjusted outcome (P =.16 for death or [re]infarction at 30 days). Despite their worse clinical profile, older patients were less likely to undergo coronary angiography at 30 days: 936 (71%), 1489 (68%), 1969 (65%), 1357 (57%), and 193 (38%) in the respective age groups. Death or (re)infarction at 30 days occurred in 121 (9%), 255 (12%), 447 (15%), 460 (19%), and 134 (26%) in the respective age groups, and at 6 months in 149 (11%), 301 (14%), 547 (18%), 575 (24%), and 162 (32%). For a 10-year difference in age group, the adjusted odds for death or (re)infarction were greater by 33% within 30 days and by 34% within 6 months. These trends persisted for patients with or without myocardial infarction on presentation. CONCLUSIONS: Age did not significantly affect the efficacy of eptifibatide. Older age among patients with acute coronary syndromes was associated with worse baseline characteristics, fewer invasive procedures, and worse outcome.

Insulin and insulin-like growth factor-I cause vasorelaxation in human vessels in vitro.

BACKGROUND: Insulin and insulin-like growth factor-I (IGF-I) are endogenous peptides with vasoactive activities. OBJECTIVE: To evaluate the vasodilatory effects of insulin and IGF-I on human vessels taken from patients with and without noninsulin-dependent diabetes mellitus (NIDDM) and to elucidate their mechanisms of action. METHODS: Vascular rings of human internal mammary artery (IMA) and saphenous vein harvested from 54 patients with and without NIDDM undergoing coronary bypass surgery were studied in vitro. RESULTS: For samples from patients without NIDDM both insulin and IGF-I (10(-12)-10(-7) mol/l) evoked greater relaxation in IMA rings (30 +/- 4 and 29 +/- 6%, maximal relaxation +/- SEM, respectively) than they did in saphenous-vein rings (43 +/- 4 and 42 +/- 5%, respectively, P < 0.05 both for insulin and for IGF-I). Similar results were obtained with vessels from patients with NIDDM. Relaxation was not affected by the removal of the endothelium and by inhibition of the production of nitric oxide. However, the vascular relaxation caused by insulin and IGF-I was completely abolished by KCI, and was attenuated by the nonspecific potassium-channel blocker tetraethylammonium (for IMA rings, to 77 +/- 8 and 66 +/- 4% with insulin and IGF-I, respectively; for saphenous vein rings, 73 +/- 2 and 77 +/- 1% for insulin and IGF-I, respectively, P < 0.001). CONCLUSIONS: Both insulin and IGF-I induced endothelial-independent, nitric oxide-independent vasorelaxation of rings from human IMA and saphenous veins, through a mechanism involving activation of potassium channels. This response remained intact in vessels from patients with NIDDM. This result supports the hypothesis that insulin and IGF-I play roles in the regulation of vascular tone in human vessels.

Cigarette smoking status and outcome among patients with acute coronary syndromes without persistent ST-segment elevation: effect of inhibition of platelet glycoprotein IIb/IIIa with eptifibatide. The PURSUIT trial investigators.

BACKGROUND: Studies have shown that cigarette smokers constitute a substantial proportion of patients with acute coronary syndromes (ACS) and have platelet-rich coronary thrombi. We characterized the influence of smoking status on outcome of patients with ACS without persistent ST-segment elevation and tested the hypothesis that selective inhibition of the platelet glycoprotein IIb/IIIa receptor with eptifibatide would improve outcomes among cigarette smokers. METHODS: The study population included patients enrolled in the PURSUIT trial (Platelet Glycoprotein IIb/IIIa in Unstable Angina: Receptor Suppression Using Integrilin Therapy) with known smoking status presenting with ischemic chest pain

Medical therapy after successful percutaneous coronary revascularization.

BACKGROUND: Percutaneous coronary revascularization frequently relieves angina in patients with ischemic heart disease and may obviate the need for antianginal medications. OBJECTIVE: To examine the use of antianginal medications after successful percutaneous coronary revascularization. DESIGN: Retrospective cohort study of the Mayo Clinic PTCA [percutaneous transluminal coronary angioplasty] Registry. SETTING: Tertiary care center. PATIENTS: 3831 patients who underwent successful percutaneous coronary revascularization from September 1979 through August 1997 and had not had myocardial infarction within the year before the intervention. MEASUREMENTS: Use of antianginal medications (beta-adrenergic blockers, nitrates, and calcium-channel blockers) before the intervention, at hospital discharge, and 6 months after the intervention. RESULTS: 99% of patients reported improvement in their symptoms at hospital discharge. At 6 months, 87% of patients were free of myocardial infarction, coronary bypass surgery, or additional percutaneous intervention. Compared with 66% of patients before the index intervention, only 12% of patients had severe angina at 6 months and 69% were completely free of angina. Nonetheless, at 6 months, 39% of patients were receiving beta-adrenergic blockers (preprocedure proportion, 43%; P < 0.001), 36% were receiving nitrates (preprocedure proportion, 41%; P < 0.001), and 57% were receiving calcium-channel blockers (preprocedure proportion, 50%; P < 0.001). These trends persisted for patients without hypertension and those who had complete revascularization. CONCLUSIONS: Successful percutaneous coronary revascularization did not substantially supplant the use of antianginal medications, which were commonly used despite the marked improvement in anginal status. This may reflect reluctance to alter therapy once symptoms of angina subside. Guidelines on continued medical therapy after percutaneous coronary revascularization are needed.

Smoking status and outcome after primary coronary angioplasty for acute myocardial infarction.

BACKGROUND: Because of the increased propensity of intracoronary thrombi to form in cigarette smokers, percutaneous transluminal angioplasty (PTCA) for acute myocardial infarction (AMI) may be less effective in smokers. We sought to determine the impact of smoking status on outcome after PTCA for AMI. METHODS: Patients enrolled in the GUSTO IIb Angioplasty Substudy were randomly assigned to receive PTCA or tissue-plasminogen activator (tPA) for AMI. The interaction of smoking status (nonsmokers = 344, former smokers = 294, current smokers = 490) and treatment strategy with the occurrence of death, nonfatal reinfarction, or nonfatal, disabling stroke at 30 days was analyzed. Procedural success (residual stenosis <50% and Thrombolysis in Myocardial Infarction [TIMI] flow grade 3) was also analyzed for patients who underwent PTCA (n = 444). RESULTS: Among patients who underwent PTCA, nonsmokers had worse percent stenosis of the culprit lesion before reperfusion (P =.03) and more often had TIMI flow grade 0 (P <.05). Procedural success was more common in smokers (65.6%) than in former smokers (53.3%) and nonsmokers (52. 4%; P =.02), reflecting a higher rate of postprocedure TIMI 3 flow. PTCA was associated with a better 30-day outcome than tPA for current smokers (odds ratio [95% confidence interval] = 0.41 [0.19 to 0.88]), with a similar trend for former smokers (0.73 [0.34 to 1. 58]) and nonsmokers (0.77 [0.42 to 1.40]). At 6 months, smokers randomly assigned to PTCA also had fewer deaths and reinfarction (0. 58 [0.31 to 1.07]). CONCLUSIONS: Although smoking status affects angiographic variables before and after PTCA for AMI, PTCA is associated with a better 30-day outcome than tPA regardless of smoking status and should be considered when readily available.

Safety and efficacy of ticlopidine for only 2 weeks after successful intracoronary stent placement.

BACKGROUND: In patients receiving intracoronary stents, stent thrombosis is reduced when ticlopidine therapy is combined with aspirin after the procedure. However, ticlopidine causes neutropenia in 1% of patients when administered for >2 weeks, and little is known about the duration that ticlopidine needs be administered to prevent stent thrombosis. METHODS AND RESULTS: We analyzed 827 patients undergoing successful stent placement in 1061 coronary segments at Mayo Clinic who were treated between May 1, 1996, and October 31, 1997. Chronic warfarin therapy, cardiogenic shock, and enrollment in research protocols requiring 4 weeks of ticlopidine were exclusion criteria; ticlopidine was discontinued after 14 days in all remaining patients. The mean age of the study population was 64+/-11 years; 49% had suffered a prior infarction, 20% had undergone coronary artery bypass surgery, and 65% had multivessel disease. The indication for stent placement was dissection or abrupt closure in 31% of patients and suboptimal results from balloon angioplasty in 18%. Placement was elective in 51% of patients, and 10.3% of patients were treated within 12 hours of an acute myocardial infarction. Mean nominal stent size was 3.3+/-0.5 mm. High-pressure inflations (>/=12 atm) were performed in all patients (mean, 17+/-4 atm). Intravascular ultrasound was used to facilitate stent placement in 8.8% of patients. Abciximab was administered to 38% of patients; 11% of patients who were at increased risk of stent thrombosis were treated with enoxaparin for 10 to 14 days. Adverse cardiovascular events in the 14 days after stent placement occurred in 11 patients (1.3%). Two patients died of nonischemic causes (sepsis and renal failure) in the 15th through 30th days after ticlopidine was stopped. However, there were no cardiovascular deaths, myocardial infarctions, coronary artery bypass operations, or repeat angioplasty procedures between the 15th and 30th days; stent thrombosis did not occur in any patient after ticlopidine had been stopped. No patient developed neutropenia, although 1.8% of the first 489 patients who were closely monitored for side effects from ticlopidine developed side effects requiring its discontinuation, and milder side effects occurred in 4.7%. CONCLUSIONS: In patients receiving intracoronary stents, the discontinuation of ticlopidine therapy 14 days after stent placement is associated with a very low frequency of stent thrombosis and other adverse events.

Prevalence of coronary blood flow reserve abnormalities among patients with nonobstructive coronary artery disease and chest pain.

OBJECTIVE: To determine the prevalence of abnormalities in endothelium-dependent and endothelium-independent coronary flow reserve among patients with non-obstructive coronary artery disease and chest pain. MATERIAL AND METHODS: We studied endothelium-dependent (after infusion of 10(-6) M to 10(-4) M of acetylcholine) and endothelium-independent (after administration of 18 to 36 micrograms of adenosine) coronary flow reserve among patients with nonobstructive coronary artery disease and chest pain who were undergoing assessment at Mayo Clinic Rochester. Coronary blood flow was derived from coronary artery diameter assessed by quantitative angiography and Doppler flow velocities. RESULTS: The cohort consisted of 203 patients (158 female and 45 male patients), who ranged in age from 17 to 78 years (mean, 51). Most patients (92%) had at least one risk factor for atherosclerosis; a substantial proportion had undergone extensive cardiac and noncardiac evaluation. Whereas 41.5% of the patients had normal coronary flow reserve, 58.5% had an abnormal response: 11.3% an impaired response to adenosine (flow velocity ratio of 2.5 or less), 29.2% an impaired response to acetylcholine (flow reserve ratio of 1.5 or less), and 18% a combined abnormality. No correlation (r2 = 0.03) was noted between endothelium-dependent and endothelium-independent flow reserve. CONCLUSION: Most study patients with chest pain and nonobstructive coronary artery disease undergoing coronary vasomotor evaluation had risk factors for coronary artery disease and diverse abnormalities in endothelium-dependent or endothelium-independent coronary flow reserve (or both). These findings underscore the need for a comprehensive assessment.

Usefulness of abciximab for treatment of early coronary artery stent thrombosis.

The clinical and angiographic outcomes of 10 patients who received abciximab as part of their therapy for early stent thrombosis was compared with 25 patients (using historical controls) who received conventional therapy. Although the angiographic outcome and the incidence of myocardial infarction in both groups was similar, there were no deaths or referral for emergency coronary bypass surgery in the abciximab-treated group versus 3 deaths and 10 referrals for emergency bypass surgery in the conventionally treated group.

Abciximab administration and outcome after intracoronary stent implantation.

Although adjunctive abciximab therapy improves outcome after angioplasty or atherectomy, there are few data demonstrating its benefit for intracoronary stent implantation. We characterized patients receiving abciximab for stent placement in our practice and determined the impact of abciximab on outcome. Abciximab was introduced to our practice in April 1995 for percutaneous revascularization. Demographic, clinical, and angiographic variables that were independently associated with the use of abciximab for stent placement through 1996 (abciximab era) were examined. We then examined among all patients receiving stents from 1992 through 1996 (preabciximab and abciximab eras) whether the use of abciximab was independently associated with improved outcome (death, nonfatal Q-wave myocardial infarction, coronary bypass surgery, or target vessel percutaneous revascularization) in the hospital and at 30 days. The 30-day event rate was 7% for those who did or did not receive abciximab. The following characteristics were independently associated with the use of abciximab for stent placement in the abciximab era: thrombus before stent placement (chi-square 50.5), > or =2 stents implanted (chi-square 10.8), stent in venous graft (chi-square 7.4), calcific lesion (chi-square 5.8), and hypertension (chi-square 5.5). Among all patients receiving stents in the preabciximab and abciximab eras (n=1,859), the presence of these characteristics was independently associated with worse outcome. Abciximab, however, did not improve outcome in the hospital (odds ratio [95% confidence interval]=0.96 [0.58 to 1.58]) or at 30 days (0.87 [0.53 to 1.41]), even after adjusting for these characteristics. Abciximab for stent placement was used in high-risk patients in our practice but was not associated with improved outcome.

Effect of basal epicardial tone on endothelium-independent coronary flow reserve measurement.

Increased basal epicardial tone may attenuate the coronary flow reserve (CFR) by causing vasodilatation of resistance vessels. We examined the effect of basal epicardial tone on the endothelium-independent CFR measurements in subjects with nonobstructive coronary disease. Patients underwent evaluation of endothelium-independent CFR using adenosine (18-36 microg) and endothelium-dependent CFR using acetylcholine (10(-6) M-10(-4) M), both administered intracoronary. CFR to adenosine, presented as the ratio of Doppler flow velocities post- and pre-adenosine, was measured at baseline and after intracoronary nitroglycerin (200 microg). Nitroglycerin increased the coronary artery diameter by 19.7 +/- 2.5%, and decreased the coronary vascular resistance from 3.0 +/- 0.2 mm Hg/ml/min to 1.8 +/- 0.1 mm Hg/ml/min (p < 0.0001). The response to adenosine at baseline and after nitroglycerin was similar (CFR ratio of 2.52 +/- 0.09 and 2.57 +/- 0.10, respectively, p = NS). The effect of nitroglycerin on the response to adenosine did not correlate with coronary endothelial function (r2 = 0.06, p = 0.13). The basal epicardial tone does not affect CFR measurements in patients with angina and nonobstructive coronary disease.

Predictors of smoking cessation after percutaneous coronary revascularization.

OBJECTIVE: To identify factors predictive of smoking cessation after successful percutaneous coronary revascularization. MATERIAL AND METHODS: We undertook a case-control study of the smoking status of all patients at Mayo Clinic Rochester from September 1979 through December 1995 who were smokers at the time of an index percutaneous coronary revascularization procedure in the non-peri-infarction setting (no myocardial infarction within 24 hours). Maximal duration of prospective follow-up was 16 years. Patients were classified into those who permanently quit smoking immediately after the procedure (N = 435; mean follow-up, 5.1 +/- 3.7 years) or those who continued to smoke at some time during follow-up (N = 734; mean follow-up, 5.3 +/- 3.7 years). Logistics regression models were formulated to determine independent predictors of smoking cessation. RESULTS: Predictors of continued smoking were greater prior cigarette consumption (odds ratio [OR] = 1.009 for each pack-year; 95% confidence interval [CI] = 1.004 to 1.014) and having one or more risk factors for coronary artery disease other than cigarette smoking (OR = 1.49; 95% CI = 1.15 to 1.93). Older age (OR = 0.98 for each additional year; 95% CI = 0.97 to 0.99) and unstable angina at time of initial assessment (OR = 0.69; 95% CI = 0.52 to 0.91) were associated with less likelihood of continued smoking. CONCLUSION: Younger patients with a worse risk profile and greater prior cigarette consumption were more likely than other patients to continue smoking after percutaneous coronary revascularization in the non-peri-infarction setting. Patients who had unstable angina were more likely to quit smoking than those who had stable angina. Despite the proven benefits of smoking cessation after percutaneous coronary revascularization, a substantial proportion of smokers (63%) continue to smoke; thus, smoking-cessation counseling should be addressed in this population.

Coronary endothelial dysfunction in humans is associated with myocardial perfusion defects.

BACKGROUND: Coronary endothelial dysfunction may occur in patients with minimally obstructive coronary artery disease and angina, and potentially may cause myocardial ischemia. METHODS AND RESULTS: Coronary endothelium-dependent vasodilation was examined in patients with angina and <50% coronary artery diameter (CAD) stenosis by selectively infusing acetylcholine (10(-6) mol/L to 10(-4) mol/L) into the left anterior descending coronary artery (LAD). Percent change in CAD (%deltaCAD) was measured by quantitative coronary angiography, and percent change in coronary blood flow (%deltaCBF) was calculated using intracoronary flow Doppler. Coronary endothelium-independent vasodilation was examined using intracoronary adenosine and nitroglycerin. 99mTc sestamibi was injected intravenously just prior to the infusion of the highest dose of acetylcholine. Patients were divided blindly into three groups: Perfusion defects in non-LAD territory (group 1, n=6), no perfusion defects (group 2, n=7), and perfusion defects in the LAD territory (group 3, n=7). All patients had intact endothelium-independent vasodilation. In group 1, perfusion defects outside the LAD territory reflected an increase in %deltaCAD and %deltaCBF by 24+/-5% and 241+/-46% in the LAD. In group 2, %deltaCAD decreased by 26+/-5%, but %deltaCBF increased by 54+/-17%. In group 3, perfusion defects were within the LAD territory, reflecting a decrease in %deltaCAD and %deltaCBF by 35+/-5% and 51+/-14%, respectively. CONCLUSIONS: This study demonstrates that coronary endothelial dysfunction in humans may be temporally associated with myocardial perfusion defects and supports a role for the coronary epicardial and microcirculation endothelium in regulating myocardial perfusion. Myocardial ischemia may occur in humans with impaired endothelium-dependent coronary flow reserve of the coronary epicardial and microcirculation.

Smokers undergoing percutaneous coronary revascularization present with fewer narrowings in the target coronary artery.

Among patients undergoing percutaneous coronary revascularization, cigarette smoking remained associated with fewer lesions in the target artery even after adjusting for age, extent of coronary artery disease, diabetes mellitus, and hypertension. These findings support the hypothesis that smokers have less active, yet more active, coronary artery disease.