Néstor Pérez Baliño

Coronary Stenting Decreases Restenosis in Lesions With Early Loss in Luminal Diameter 24 Hours After Successful PTCA

BACKGROUND Early loss of minimal luminal diameter (MLD) after successful percutaneous transluminal coronary angioplasty (PTCA) is associated with a higher incidence of late restenosis. METHODS AND RESULTS Sixty-six patients (66 lesions) with > 0.3 mm MLD loss at 24-hour on-line quantitative coronary angiography were randomized into two groups: 1, Gianturco-Roubin stent (n = 33) and 2, Control, who received medical therapy only (n = 33). All lesions were suitable for stenting. Baseline demographic, clinical, and angiographic characteristics were similar in the two groups. Restenosis (> or = 50% stenosis) for the overall group occurred in 32 of 66 patients (48.4%) at 3.6 +/- 1-month follow-up angiography. Restenosis was significantly greater in group 2 than in group 1 (75.7% versus 21.2%, P < .001). Vascular complications (21.2% versus 0%) and length of hospital stay (7.3 +/- 1 versus 2.4 +/- 0.5 days, P < .01) were higher for the stent group. Although at follow-up there were no differences in mortality or incidence of acute myocardial infarction between the two groups, patients in the control group had a higher incidence of repeat revascularization procedures (73% versus 21%, P < .001). CONCLUSIONS In patients with successful PTCA but reduced luminal diameter demonstrated by repeat angiography at 24 hours, the Gianturco-Roubin stent appears to reduce angiographic restenosis at follow-up.

Effect of endothelial dysfunction on regional perfusion in myocardial territories supplied by normal and diseased vessels in patients with coronary artery disease

BackgroundEndothelium-dependent regulation of coronary tone affects both conduit and resistance coronary arteries. However, little is known about the usefulness of myocardial perfusion imaging in evaluating coronary endothelial function. We evaluated the relation between invasive angiographic measurements of coronary vasomotion in response to intracoronary acetylcholine and the presence of regional perfusion abnormalities assessed by technetium 99m sestamibi imaging.Methods and ResultsWe studied 11 patients (9 men and 2 women) with suspected coronary artery disease (48±8 years, mean±standard deviation). We used quantitative coronary angiography to delineate the vasomotor response to increasing doses of acetylcholine given intracoronary. Regional myocardial perfusion was assessed by planar Tc-99m sestamibi imaging during and after the administration of acetylcholine. In the 11 patients, 23 coronary artery territories were analyzed: 13 were angiographically normal, and 10 showed varying degrees of luminal narrowing. Four (31%) of 13 angiographically normal coronary arteries had a positive vasomotor response to acetylcholine (≥20% reduction in luminal diameter) that was associated with a regional perfusion defect. Acetylcholine induced a positive vasomotor response, which was also associated with a regional perfusion defect in 1 of 3 coronary arteries with stenoses of intermediate severity (50% to 69%). Likewise, acetylcholine induced a positive vasomotor response in 6 of 7 coronary arteries with significant luminal narrowing (≥70%), 5 of which showed a corresponding regional perfusion defect.ConclusionsIn patients with coronary artery disease, noninvasive measurements of regional myocardial perfusion by Tc-99m sestamibi correlate well with invasive measurements of coronary endothelial function. These findings may have implications for monitoring the effects of interventions designed to improve endothelial function and microvascular function in patients with coronary artery disease.

Use of nebivolol for the treatment of endothelial dysfunction in patients with hypertension: the EDEN registry.

This aim of this study was to evaluate the presence of endothelial dysfunction in patients with primary hypertension and to determine the usefulness of nebivolol, a selective β-adrenoceptor blocking agent, as a potential treatment for endothelial dysfunction. Of 176 patients with stage I hypertension, 36 patients (20%), the majority of whom were overweight/obese, were found to have abnormal results with myocardial perfusion single-photon emission computed tomography (MP-SPECT) under cold pressor test conditions. These 36 patients were treated for 28 days with 5 mg/d nebivolol, after which only 3 (8.3%) still had abnormal MP-SPECT results. The mean ischemia score was consistent with moderate risk and decreased significantly after treatment with nebivolol. All hemodynamic variables measured (systolic and diastolic blood pressure and heart rate) were also reduced significantly by treatment with nebivolol. Endothelial dysfunction plays a key role in the pathogenesis of atherosclerosis and its reversal has considerable implications for clinical outcomes in affected patients. The cold pressor testing results of this study suggest that nebivolol may have beneficial anti-ischemic effects in the coronary arteries of patients with hypertension. However, these findings need to be confirmed in larger randomized controlled trials, ideally comparing nebivolol with other blood pressure lowering agents or NO synthase inhibitors.

Usefulness of radionuclide ventriculography in assessment of coronary artery spasm

Provocative tests that permit detection of coronary artery spasm are widely used in patients with ischemic syndromes. To assess the usefulness of radionuclide ventriculography combined with provocative tests for diagnosis of coronary spasm, the left ventricular (LV) response to exercise, hyperventilation and a cold pressor test was determined in 3 groups. Group I included 10 normal subjects; group II, 49 patients with typical effort angina and fixed obstructive coronary artery disease at catheterization; and group III, 19 patients suspected of having vasospastic angina based on clinical and electrocardiographic findings, each of whom had normal coronary angiographic findings. In group I, LV ejection fraction (EF) increased during hyperventilation and exercise testing in 9 of 10 subjects (90%) and failed to decrease 5% in 9 of 10 subjects (90%) during cold testing. In contrast, while 18 of 49 patients (37%) of group II showed LV dysfunction with cold testing and 8% with hyperventilation, all showed abnormal LV function during exercise. Finally, in group III, LVEF increased during exercise, mimicking the response in normal group, while dysfunction was present in 14 of 19 (74%) during hyperventilation and in 17 of 19 (89%) during cold testing. When results of hyperventilation and cold testing were combined, abnormal responses were present in all patients. Thus, radionuclide ventriculography, when performed in association with 3 forms of stress--exercise, hyperventilation and cold testing--allows accurate identification of patients likely to have coronary spasm.