Does carotid intima-media thickness regression predict reduction of cardiovascular events? A meta-analysis of 41 randomized trials.

OBJECTIVES: the purpose of this study was to verify whether intima-media thickness (IMT) regression is associated with reduced incidence of cardiovascular events. BACKGROUND: Carotid IMT increase is associated with a raised risk of coronary heart disease (CHD) and cerebrovascular (CBV) events. However, it is undetermined whether favorable changes of IMT reflect prognostic benefits. METHODS: the MEDLINE database and the Cochrane Database were searched for articles published until August 2009. All randomized trials assessing carotid IMT at baseline, at end of follow-up, and reporting clinical end points were included. A weighted random-effects meta-regression analysis was performed to test the relationship between mean and maximum IMT changes and outcomes. The influence of baseline patients' characteristics, cardiovascular risk profile, IMT at baseline, follow-up, and quality of the trials was also explored. Overall estimates of effect were calculated with a fixed-effects model, random-effects model, or Peto method. RESULTS: forty-one trials enrolling 18,307 participants were included. Despite significant reduction in CHD, CBV events, and all-cause death induced by active treatments (for CHD events, odds ratio [OR]: 0.82, 95% confidence interval [CI]: 0.69 to 0.96, p = 0.02; for CBV events, OR: 0.71, 95% CI: 0.51 to 1.00, p = 0.05; and for all-cause death, OR: 0.71, 95% CI: 0.53 to 0.96, p = 0.03), there was no significant relationship between IMT regression and CHD events (tau(2)0.91, p = 0.37), CBV events (tau(2)-0.32, p = 0.75), and all-cause death (tau(2)-0.41, p = 0.69). In addition, subjects' baseline characteristics, cardiovascular risk profile, IMT at baseline, follow-up, and quality of the trials did not significantly influence the association between IMT changes and clinical outcomes. CONCLUSIONS: regression or slowed progression of carotid IMT, induced by cardiovascular drug therapies, do not reflect reduction in cardiovascular events.

Effects of AT1 receptor antagonism with candesartan on endothelial function in patients with hypertension and coronary artery disease.

Endothelial dysfunction is a major determinant of atherosclerosis and a negative prognostic factor in patients with coronary artery disease and hypertension. Recovery of endothelial dysfunction has been associated with improved prognosis in these patients. The aim of the present study was to verify whether antagonism of angiotensin II AT1 receptors with an angiotensin receptor blocker, candesartan, improved endothelial function in patients with hypertension, stable coronary artery disease, and endothelial dysfunction. We studied 26 patients who were receiving beta-blockers with optimal blood pressure control, in a randomized, double blind study. Patients were randomized to placebo (n=13) or to candesartan 16 mg/d (n=13) for 2 months. Endothelial function was assessed by ultrasound using hyperemic flow-mediated dilation of the brachial artery. Mean arterial blood pressure was unchanged in both groups (from 93.3 +/- 9.2 to 93.2 +/- 17.3 mm Hg in the candesartan group and from 101.3 +/- 14.2 to 102.3 +/- 13.9 mm Hg in the placebo group; both P=ns). Maximal blood flow was similar between placebo and candesartan groups at baseline and at the end of the study, whereas flow-mediated dilation significantly increased in the candesartan group (from 5.27% +/- 1.69% to 7.15% +/- 2.67%; P=0.01) but remained unchanged in the placebo group (from 4.49% +/- 1.97% to 5.88% +/- 2.30%; P=ns). AT1 receptor antagonism with candesartan, in addition to b-blocker therapy, improves endothelial function in high-risk hypertensive patients.

Rest-redistribution 201-Thallium single photon emission computed tomography predicts myocardial infarction and cardiac death in patients with ischemic left ventricular dysfunction.

UNLABELLED: The prognostic role of rest-redistribution 201-Thallium imaging has not been extensively investigated in patients with left ventricular ischemic dysfunction. OBJECTIVE: The aim of this study was to evaluate the ability of rest-redistribution 201-Thallium single photon emission computed tomography to predict cardiac death and occurrence of acute myocardial infarction in patients with ischemic mild-to-moderate left ventricular dysfunction. METHODS: One-hundred and twenty-six patients with chronic coronary artery disease and mean left ventricular ejection fraction 39 +/- 11% were followed-up for 30 +/- 17 months after a rest-redistribution 201-Thallium imaging single photon emission computed tomography. Cardiac death and acute myocardial infarction were considered as major cardiac events. RESULTS: During the follow up, 11 (9%) cardiac deaths and 9 (7%) acute myocardial infarctions occurred. The only variable showing significant difference between patients with and without events was the number of severe irreversible defects (1.7 +/- 1.9 versus 0.9 +/- 1.2, respectively; P = 0.02). By Kaplan-Meier analysis, the presence of three or less, or more than three severe defects was selected as the best cutoff to identify patients with longer event-free survival from cardiac death or acute myocardial infarction (log rank 19.84; P < 0.0001). When only cardiac death was considered as clinical event, the presence of at least two severe defects best separated patients who died from those who survived (log rank 8.68; P = 0.0032). CONCLUSION: Rest-redistribution 201-Thallium single photon emission computed tomography provides prognostic information in coronary patients with mild-to-moderate left ventricular dysfunction. The number of severe irreversible defects per patient is a powerful predictor of prognosis.

[The role of myocardial scintigraphy in the assessment of coronary artery disease]. / Il ruolo della scintigrafia miocardica nella valutazione della cardiopatia ischemica.

Single photon emission computed tomography (SPECT) for the assessment of myocardial perfusion was introduced in the early 1970s, following pioneer studies of Gould et al. It has rapidly become one of the most used noninvasive technique for the assessment of myocardial ischemia. Thanks to the current technetium based tracers that allow electrocardiogram gated synchronization, it is possible to assess the regional ventricular systolic function and the evaluation of myocardial perfusion as well. In the last twenty years, beyond its diagnostic role, myocardial SPECT has become also a prognostic technique. Indeed, it has acquired a role for the short-term prediction of major coronary events in a large cohort with known or suspected coronary artery disease (CAD). The aim of this review is to give an update of the correct use and interpretation of myocardial SPECT in patients with known or suspected CAD and without left ventricular dysfunction.