Siguemituzo Arie

Short-term Anti-Ischemic Effect of 17β-Estradiol in Postmenopausal Women With Coronary Artery Disease

BACKGROUND Short-term administration of 17beta-estradiol improves effort-induced myocardial ischemia in female patients with coronary artery disease. 17Beta-estradiol also has direct and indirect coronary vascular smooth muscle relaxing properties. The aim of the present study was to evaluate the effect of short-term administration of 17beta-estradiol on pacing-induced myocardial ischemia by means of continuous monitoring of coronary sinus pH in 16 postmenopausal female patients with coronary artery disease. METHODS AND RESULTS Patients underwent incremental atrial pacing starting at a rate of 100 bpm and increments of 20 bpm every 2 minutes up to 160 bpm before and 20 minutes after either 17beta-estradiol (1 mg sublingual, 9 patients) or placebo (sublingual, 7 patients). The time to the onset of myocardial ischemia during pacing was significantly increased by 17beta-estradiol (mean+/-SD, 254+/-36 versus 298+/-23 seconds; P<.02) but not by placebo (262+/-45 versus 256+/-34 seconds; P=NS) The pH shift was significantly reduced by 17beta-estradiol but not by placebo at every step of the pacing protocol. The maximum pH shift at peak pacing was significantly reduced by the administration of 17beta-estradiol by 0.022 pH units (95% CI, 0.001, 0.043; P<.04) but not by sublingual placebo (-0.002 pH units; 95% CI, -0.0073, 0.0021; P=NS). The maximum pH shift at maximum comparable pacing was also reduced by 17beta-estradiol by 0.015 pH units (95% CI, 0.012, 0.017; P<.001) but not by placebo (-0.0022 pH units; 95% CI, -0.006, 0.0015; P=NS). CONCLUSIONS 17Beta-estradiol reduces the degree of pacing-induced myocardial ischemia in postmenopausal patients with coronary artery disease. The reduction of pacing-induced coronary sinus pH shift is consistent with an anti-ischemic effect of the hormone and is not due to preconditioning, as evidenced by the absence of improvement after placebo.

Histological patterns of atherosclerotic plaques in unstable angina patients vary according to clinical presentation

Background Unstable angina is a heterogeneous clinical syndrome. The diverse clinical presentations of unstable angina may reflect different pathogenic mechanisms within the plaque. Objective To investigate the cellular constituents of culprit coronary atheromatous plaques in patients with stable angina pectoris and patients with diverse clinical presentations of unstable angina. Methods 48 patients who underwent coronary atherectomy for management of ischaemic heart disease: 23 had stable angina and 25 had unstable angina. Of the latter, 11 patients were classified as Braunwald’s IIB and 14 as Braunwald’s IIIB unstable angina. The presence of thrombus, cholesterol clefts, and smooth muscle cell proliferation was assessed in atherectomy samples using standard histological techniques. Monoclonal antibodies were used to identify smooth muscle cells and macrophages within atherosclerotic plaque fragments. Results Fresh thrombus was more frequently found in patients with Braunwald’s IIIB unstable angina (64%) than in patients with stable angina (22%) or IIB unstable angina (27%) (p < 0.0006). A pattern of smooth muscle cell proliferation (“accelerated progression pattern”) was observed which was also associated with coronary thrombus. This pattern was present in 30% of patients with stable angina, 64% of patients with IIIB unstable angina, and in all patients (100%) with IIB unstable angina. Atherosclerotic plaques with thrombus, cholesterol clefts, and macrophages were more common in patients with unstable angina than in stable angina patients. Conclusion The presence of a specific smooth muscle cell proliferation (accelerated progression) pattern in patients with unstable angina, particularly in those with Braunwald’s IIB unstable angina, suggests that episodic plaque disruption and subsequent healing may be an important mechanism underlying angina symptoms in these patients.

Hemodynamic determinants of coronary constriction in human myocardial bridges

To study the physiopathology of myocardial bridges, we assessed the degree of systolic coronary artery constriction (%SC) in different hemodynamic situations in six patients submitted for coronary angiograms. There was an increase of %SC (p less than 0.05) with sodium nitroprusside (NP), no modification during fast atrial stimulation (AS), and a decrease (p less than 0.05) during noradrenaline infusion (Nor). Hemodynamic studies indicate an inverse relation (p less than 0.05) between %SC and systolic and diastolic aortic pressure and left ventricular dP/dt. There was no correlation between changes in %SC and changes in Vmax or heart rate. Thus we conclude that changes in systemic arterial pressure and coronary perfusion pressure may significantly affect the degree of severity of myocardial bridges, possibly through an influence upon intraluminal coronary pressure and an intramyocardial tension relationship.

Successful coronary atherectomy during acute myocardial infarction

Abstract Immediate angiographic results and early follow-up of a patient treated with coronary atherectomy during the initial phase of acute myocardial infarction are evaluated.

Persistência de distúrbios perfusionais miocárdicos após intervenção coronária percutânea com êxito: dependência de fatores microcirculatórios

INTRODUCTION: The transitory persistence of perfusion defects immediately after successful percutaneous coronary interventions to correct coronary stenosis is well known METHODS: To test the hypothesis that such perfusion abnormalities are associated with microcirculatory disorders caused by coronary microembolization we compared the intensity and extent of these perfusion defects detected using myocardial scintigraphy in groups of patients randomly assigned to coronary balloon angioplasty (BA) or to rotational atherectomy plus balloon angioplasty (RA + B). The clinical and angiography characteristics were comparable in both groups, as well as the success of the coronary angioplasty procedure. RESULTS: Before the percutaneous coronary intervention the myocardium defect index, related to the extent and severity of hypoperfusion, was comparable for the two groups, both under stress (AB = 7.72±1.91 vs. RA + B = 8.61±3.38) and at rest (AB = 3.11±1.22 vs. RA + B = 2.40±1.63). After the procedure, the perfusion defect index decreased for both groups during stress, but with statistical significance only in the AB Group = 3.96±1.40 vs. RA + B = 3.71±1.89. The difference between the two groups was greater at rest after the coronary intervention procedure: the defect index decreased with marginal significance for the AB Group to 1.46±0.66 and increased, though without statistical significance, for the RA + B Group to 3.47±1.92. CONCLUSION: These results are compatible with the notion that transitory persistence of perfusion defects after successful coronary angioplasty are dependent on microcirculatory disorders associated to microembolization during the procedure.

Implante de stent dentro de stent recém-implantado em ponte de veia safena para otimização do resultado angiográfico

A 60 year-old woman with progressive angina who had been submitted to saphenous bypass-graft to right coronary artery and a left mammary artery graft to anterior descending artery eight years previously, underwent implantation of a Gianturco Roubin II stent in the proximal third of the saphenous vein graft. The result was suboptimal by persistence of a residual stenosis probably due to prolapse of atherosclerotic material through the coil spaces. Another stent (Palmaz-Schatz biliar stent) was implanted at the previously stented site with no residual stenosis. Another Palmaz-Schatz biliar stent was successfully implanted in the distal body of the graft to treat another lesion (passing through the previously stents without difficulty). Stenting a stent, in selected situations, is a useful tool to optimize the angiographic result of stent implantation.

Sublingual isosorbide-5 mononitrate during coronary arteriography. Comparison with sublingual nitroglycerin

PURPOSE To evaluate the effect of sublingual isosorbide-5 mononitrate (ISMN) and nitroglycerin (NTG) on luminal diameter of epicardial coronary arteries, mean arterial pressure and deleterious effects. METHODS Fifty patients were submitted to cardiac catheterization and coronary arteriography, at baseline, and 5 min after sublingual administration of ISMN, group A (GA) or NTG, group B (GB). RESULTS Reference vessel diameter increased in both groups, without statistical significance. In GA and GB, a decrease (1.66 mmHg) and an increase (0.79 mmHg) in mean arterial pressure, respectively, were demonstrated (p = 0.123). There were no deleterious effects with the use of these drugs. CONCLUSION Sublingual ISMN is an alternative to administration of NTG during coronary arteriography, and represents a therapeutic alternative to ischemic heart disease treatment.

A perda precoce do diâmetro luminal após angioplastia coronária e sua influência no fenômeno da reestenose

OBJETIVO: Analisar a perda do diâmetro luminal minimo (DLM) nos primeiros 15min apos angioplastia coronaria por balao (AC), quantificando sua influencia na reestenose coronaria. METODOS: Foram estudadas, prospectivamente, 86 AC em 86 pacientes. Os pacientes foram divididos em dois subgrupos de acordo com a presenca ou ausencia de reestenose; o 1o grupo compreendendo as 31 lesoes com reestenose e o 2o, as 55 lesoes sem reestenose. RESULTADOS: A analise univariada mostrou que a relacao balao/arteria foi menor no grupo com reestenose (0,92±0,01 vs 1,00±0,11, P= .003). O grupo com reestenose apresentou maior recolhimento elastico absoluto e relativo no 1°min (0,79±0,54 vs 0,68±0,59mm; P= 0,007 e 32,04±14,27 vs 22,15±16,65%; P= 0,006.) e no controle angiografico do 15°min (1,25±0,59 vs 0,90±0,65mm, P= 0,017 e 46,75±15,69 vs 29,18±17,84%, P<0,00001) do que o grupo sem reestenose. O DLM no 1°min foi menor no grupo com reestenose (2,15±0,42 vs 2,43±0,58mm; P=0,022). O grupo com reestenose apresentou uma maior perda precoce no DLM (0,46±0,34 vs 0,22±0,35mm, P= 0,004). Este decrescimo na luz do vaso determinou que o DLM do 15°min fosse ainda menor no grupo com reestenose (1,69±0,48 vs 2,20±0,61; P= 0,0001). Da analise multivariada, entretanto, identificou-se apenas a relacao balao/arteria e o DLM do 15°min como os dois fatores independentes mais relacionados a reestenose. CONCLUSAO: O recolhimento elastico e a perda do DLM ao longo dos 15min sao fatores diretamente relacionados a reestenose. Entretanto, a analise multivariada mostrou que a relacao balao/arteria e o DLM de 15min sao os dois fatores independentes mais fortemente preditores de reestenose.Purpose To evaluate the early luminal diameter loss in the first 15min after percutaneous transluminal coronary angioplasty (PTCA) and its influence on coronary restenosis. Methods In a prospective study, we evaluated 86 patients. The patients were divided in two groups based on the presence or absence of coronary restenosis. Thirty one lesions developed restenosis and 55 lesions did not. Results Univariate analysis showed that balloon/ artery ratio was lower in the group of restenosis (0.92±0,01 vs 1.00±0,11, P= .003). Absolute and relative elastic recoil at 1 min was greater in the group that developed restenosis (0.79±0.54 vs 0.68±0.59mm; P= .007 and 32.04±14.27 vs 22.15±16.65%; P= .006). Similarly, absolute and relative elastic recoil at 15 min were greater in the group with restenosis (1.25±0.59 vs 0.90±0.65mm, P= .017 e 46.75±15.69 vs 29.18±17.84%, P< .00001). Minimal luminal diameter( MLD) at 1min was lower in the group with restenosis (2.15±0.42 vs 2.43±0.58mm; P= .022). The very early loss was greater in the group with restenosis (0.46±0.34 vs 0.22±0.35mm, P= .004). MLD at 15 min was lower in the group of restenosis than in the group without restenosis (1.69±0.48 vs 2.20±0.61; P= .0001). Multivariate analisys revealed balloon/artery ratio and MLD at 15 min as independent correlates of the late outcome. Conclusion The late outcome of PTCA is influenced by elastic recoil and the early MLD loss after PTCA. However, the strongest and most important predictors of late outcome by multivariate analysis were balloon/artery ratio and MLD at 15 min.