Intra- and interreader reproducibility of magnetic resonance imaging for quantifying the lipid-rich necrotic core is improved with gadolinium contrast enhancement.

PURPOSE: To test the hypothesis that intra- and interreader reproducibility for measuring the lipid-rich necrotic core (LR-NC) size is significantly improved with gadolinium (Gd) contrast-enhanced magnetic resonance imaging (CEMRI) compared to non-CEMRI. MATERIALS AND METHODS: Thirty-seven individuals with >50% carotid artery stenosis underwent carotid MRI at 1.5T (pre- and postcontrast T1-weighted (T1W), T2-weighted (T2W), proton density-weighted (PDW), and three-dimensional time-of-flight (TOF) sequences). Two independent readers measured the mean area of the LR-NC from the precontrast images only, followed by a second measurement using the additional postcontrast images. One reader repeated the measurements after an interval of five months. Intra- and interreader reproducibility was analyzed by means of the intraclass correlation coefficient (ICC), coefficient of variation (CV), and standard deviation (SD). RESULTS: The CV decreased from 33.7% to 8.8% for intrareader measurements of the LR-NC, and from 33.5% to 17.6% for interreader measurements. The SD was significantly smaller with CEMRI than with non-CEMRI (P = 0.003 and P = 0.006, respectively). The ICC increased from 0.94 to 0.99 and from 0.85 to 0.93 for the intra- and interreader measurements, respectively. CONCLUSION: Reader reproducibility for in vivo MRI quantification of LR-NC size is significantly improved by the addition of Gd contrast in individuals with >50% carotid stenosis.

Results of the Controlled ONset Verapamil INvestigation of Cardiovascular Endpoints (CONVINCE) trial by geographical region.

OBJECTIVE: To examine regional differences in the Controlled ONset Verapamil INvestigation of Cardiovascular Endpoints (CONVINCE) trial. DESIGN: Double-blind, randomized, international clinical trial. SETTING: Six hundred and sixty-one clinical centers in 15 countries. PATIENTS: Hypertensive volunteers (n = 16,602) with > or =1 additional cardiovascular risk factor, grouped into four regions: USA (n = 8144), Canada (n = 3405), Western Europe (Spain, UK, Italy, Sweden, Germany; n = 2048) or 'other' (Bulgaria, Israel, Mexico, Czech Republic, Hungary, Poland, Slovakia, Brazil; n = 2879); subgroupings included country and state/province within the USA and Canada. INTERVENTIONS: Randomized to COER-verapamil or the investigator's choice of either atenolol or hydrochlorothiazide, titrated and additional drugs added as required. MAIN OUTCOME MEASURES: Baseline characteristics; blood pressure control, medication adherence and lost-to-follow-up at 2 years; and composite primary endpoint (stroke, myocardial infarction, cardiovascular death) by regional groupings. RESULTS: Regional differences were found at baseline for age, gender, blood pressure, percentage receiving antihypertensive drug therapy, initial choice of atenolol or hydrochlorothiazide, and risk factor profile. Blood pressure control rates increased markedly during follow-up in all regions, but varied significantly by region. Blood pressure control, medication adherence and lost-to-follow-up rates were poorest in the USA. After adjustment for baseline differences, the primary-event rate for each region was significantly lower than for the USA. Although baseline factors, blood pressure control and event rates varied by region, treatment differences did not. CONCLUSION: Despite differences in baseline and follow-up measures across geographical regions, the absence of treatment differences by region suggests that the overall findings of CONVINCE are robust.

Role of oral blockade of platelet glycoprotein IIb/IIIa on neutrophil activation in patients with acute coronary syndromes.

Orbofiban is a unique antiplatelet agent that inhibits the binding of fibrinogen to gycoprotein (GP) IIb/IIIa integrin receptors and thus prevents platelet aggregation induced by various agents. However, recent studies indicate that treatment with orbofiban does not reduce the incidence of recurrent ischemic events. The mechanisms underlying the lack of benefit of orbofiban in patients with acute coronary syndromes are not completely clear. The purpose of this study was to characterize the effects of orbofiban on cellular activation (neutrophil superoxide generation) and surface expression of adhesion molecules of circulating neutrophils (CD18, CD11b, and L-selectin) and platelets (P-selectin and GP IIb/IIIa) in patients with acute coronary syndromes. After 5-7 days, orbifiban (50 mg BID) did not reduce PMN adhesion molecule expression and ex vivo-stimulated PMN superoxide generation--as was observed in the placebo group, without orbofiban. In contrast, orbofiban induced marked reductions in GP IIb/IIIa and P-selectin expressions after 5-7 days of treatment. The sustained neutrophil activation observed with orbofiban may have a role on the recurrent thrombotic events observed with orbofiban treatment in the OPUS-TIMI 16 trial.

Principal results of the Controlled Onset Verapamil Investigation of Cardiovascular End Points (CONVINCE) trial.

CONTEXT: Hypertensive patients are often given a calcium antagonist to reduce cardiovascular disease risk, but the benefit compared with other drug classes is controversial. OBJECTIVE: To determine whether initial therapy with controlled-onset extended-release (COER) verapamil is equivalent to a physician's choice of atenolol or hydrochlorothiazide in preventing cardiovascular disease. DESIGN, SETTING, AND PARTICIPANTS: Double-blind, randomized clinical trial conducted at 661 centers in 15 countries. A total of 16 602 participants diagnosed as having hypertension and who had 1 or more additional risk factors for cardiovascular disease were enrolled between September 1996 and December 1998 and followed up until December 31, 2000. After a mean of 3 years of follow-up, the sponsor closed the study before unblinding the results. INTERVENTION: Initially, 8241 participants received 180 mg of COER verapamil and 8361 received either 50 mg of atenolol or 12.5 mg of hydrochlorothiazide. Other drugs (eg, diuretic, beta-blocker, or an angiotensin-converting enzyme inhibitor) could be added in specified sequence if needed. MAIN OUTCOME MEASURES: First occurrence of stroke, myocardial infarction, or cardiovascular disease-related death. RESULTS: Systolic and diastolic blood pressure were reduced by 13.6 mm Hg and 7.8 mm Hg for participants assigned to the COER verapamil group and by 13.5 and 7.1 mm Hg for partcipants assigned to the atenolol or hydrochlorothiazide group. There were 364 primary cardiovascular disease-related events that occurred in the COER verapamil group vs 365 in atenolol or hydrochlorothiazide group (hazard ratio [HR], 1.02; 95% confidence interval [CI], 0.88-1.18; P =.77). For fatal or nonfatal stroke, the HR was 1.15 (95% CI, 0.90-1.48); for fatal or nonfatal myocardial infarction, 0.82 (95% CI, 0.65-1.03); and for cardiovascular disease-related death, 1.09 (95% CI, 0.87-1.37). The HR was 1.05 (95% CI, 0.95-1.16) for any prespecified cardiovascular disease-related event and 1.08 (95% CI, 0.93-1.26) for all-cause mortality. Nonstroke hemorrhage was more common with participants in the COER-verapamil group (n = 118) compared with the atenolol or hydrochlorothiazide group (n = 79) (HR, 1.54 [95% CI, 1.16-2.04]; P =.003). More cardiovascular disease-related events occurred between 6 AM and noon in both the COER verapamil (99/277) and atenolol or hydrochlorothiazide (88/274) groups; HR, 1.15 (95% CI, 0.86-1.53). CONCLUSIONS: The CONVINCE trial did not demonstrate equivalence of a COER verapamil-based antihypertensive regimen compared with a regimen beginning with a diuretic or beta-blocker. When considered in the context of other trials of calcium antagonists, these data indicate that the effectiveness of calcium-channel therapy in reducing cardiovascular disease is similar but not better than diuretic or beta-blocker treatment.

Preventing increases in early-morning blood pressure, heart rate, and the rate-pressure product with controlled onset extended release verapamil at bedtime versus enalapril, losartan, and placebo on arising.

BACKGROUND: Therapeutic agents for the treatment of hypertension may differ in their efficacy during the early-morning period, a time when both morbid and mortal cardiovascular events are increased compared with other times of the day. METHODS: We studied the effects of a chronotherapeutic delivery system of verapamil (controlled-onset extended release [COER]-24 system) dosed at bedtime versus conventional morning administration of both enalapril and losartan on the blood pressure (BP), heart rate, and the heart rate systolic BP product during the first 4 hours after awakening in a placebo-controlled, forced-titration trial. There were 357 men and women enrolled in the trial with an untreated sitting diastolic BP of 95 to 114 mm Hg and ambulatory daytime diastolic BP > or =85 mm Hg. Patients were randomized to either COER-verapamil hydrochloride each evening (240 mg titrated to 360 mg), enalapril each morning (10 mg titrated to 20 mg), losartan each morning (50 mg titrated to 100 mg), or placebo. Early morning assessments of BP, heart rate, and the heart rate systolic BP product were performed by use of 24-hour ambulatory recordings after 4 weeks (low dose) and 8 weeks (high dose) of therapy. RESULTS: Results were similar at weeks 4 and 8 for all treatment groups except that the magnitude of change was greater at week 8. After 8 weeks of treatment, reductions in early morning BP by COER-verapamil were significantly greater (-15/-10 mm Hg) than enalapril (-9/-7 mm Hg, P <.01) and losartan (-8/-5 mm Hg, P <.001). COER-verapamil also led to greater reductions in morning heart rate, the rate-pressure product, and the rate-of-rise of BP compared with the other 2 active treatment groups. Reductions in mean 24-hour BP were greater in patients treated with COER-verapamil compared with placebo and losartan, and similar to reductions in patients treated with enalapril. CONCLUSIONS: Bedtime administration of an agent designed to parallel the circadian rhythm of BP and heart rate led to significantly greater early morning hemodynamic effects compared with other conventional once-daily antihypertensive agents dosed in the morning.

A comparative trial of controlled-onset, extended-release verapamil, enalapril, and losartan on blood pressure and heart rate changes.

BACKGROUND: The excess morning risk of myocardial infarction and stroke may be attributable to the rapid rise in blood pressure (BP) and heart rate in the hours after awakening. The aim of this randomized, double-blinded, placebo-controlled, multicenter study was to compare once-daily, controlled-onset, extended-release (COER-24) verapamil to enalapril and losartan on BP and heart rate during the postawakening morning phase as well as throughout the 24-h period. METHODS: A total of 406 patients were randomized to an 8-week forced-titration period with one of the following: 1) COER-24 verapamil 240 mg/day titrated to 360 mg/day; 2) enalapril 10 mg/day titrated to 20 mg/day, 3) losartan 50 mg/day titrated to 100 mg/day, or 4) placebo. Office BP and heart rate and ambulatory 24-h BP monitoring was performed at baseline, 4 weeks, and 8 weeks. RESULTS: Each active treatment, as compared with placebo, lowered BP both during the morning hours as well as the entire 24-h period. COER-24 verapamil was more effective in lowering morning systolic (-16.6 mm Hg) and diastolic (-11.9 mm Hg) BP than either enalapril or losartan (P < .001). For the entire 24-h period, the effects of COER-24 verapamil (-11.6/-8.4 mm Hg) were comparable to enalapril (- 13.4/-8.3 mm Hg; P = NS). Losartan achieved a similar 24-h effect on systolic pressure (-9.3 mm Hg) but was less effective on diastolic pressure (-5.4 mm Hg; P = .004 v COER-verapamil). Unlike losartan or enalapril, COER-24 verapamil was the only treatment to lower the heart rate over both the 24-h period (-4.6 beats/min; P < .001) and during waking hours (-4.6 beats/min; P < .001). A blunted rate of rise in BP, heart rate, and rate-pressure product occurred during the postawakening period with COER-verapamil (P = .03) but not with either of the other treatment arms. Lastly, the decline in BP at night was similar for COER-verapamil and losartan and greater with enalapril (P = .014) CONCLUSIONS: COER-24 verapamil produces changes in BP and pulse that more closely match the normal circadian hemodynamic rhythms than either do enalapril or losartan.

Baseline Characteristics and Early Blood Pressure Control in the CONVINCE Trial.

-Blood pressure (BP) control rates around the world are suboptimal. Part 2 of the National Health and Nutrition Educational Survey (NHANES) III indicates that only 27.4% of hypertensive Americans aged 18 to 74 years have a BP of <140/90 mm Hg. We wanted to assess BP control during the first 2 years and to describe the baseline characteristics of patients enrolled in the Controlled ONset Verapamil INvestigation of Cardiovascular Endpoints (CONVINCE) Study, an international clinical trial that compares outcomes in hypertensive patients randomized to initial treatment with either controlled-onset extended-release verapamil or the investigator's choice of atenolol or hydrochlorothiazide. At randomization, BP was <140/90 mm Hg in only 20.3% of the 16 602 subjects (average+/-SD age 65.6+/-7.4 years; 56% women, 84% white/7% black/7% Hispanic). The average BP at enrollment was 148/85 mm Hg for patients taking BP medications (n=13 879) and 161/94 mm Hg for previously untreated patients (n=2723). After medication titration, with a transtelephonic computer that recommended an increase in the dose or number of antihypertensive agents whenever the BP was 140/90 mm Hg, 84.8% of the subjects attained the goal BP. During 2 years of treatment, BP control was maintained in 67% to 69% of the subjects (69% to 71% for systolic BP of <140 mm Hg and 90% for diastolic BP of <90 mm Hg). These data suggest that the control of systolic BP is more difficult than the control of diastolic BP. The US national goal of having 50% of hypertensives with a BP of <140/90 mm Hg may be achievable if a forced titration strategy is used. Interested investigators, free care and medications, and well-educated subjects may make the attainment of such a goal easier in the CONVINCE study than in the general population.