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.
Despite severe chest pain and reduced coronary flow reserve after pacing, most patients with angina and normal coronary arteriograms do not show metabolic evidence of myocardial ischaemia.
Myocardial Perfusion Disturbances Persisting after Successful Percutaneous Coronary Angioplasty: Relationship to Microcirculatory Derangements 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.
Percutaneous balloon mitral valvotomy (BMV) is an alternative therapeutic method for patients with mitral stenosis. We studied 62 patients (56 females, mean age 36.4 years) who underwent balloon mitral valvotomy. Five patients were pregnant and in New York Heart Association Functional Class IV. Doppler echocardiographic studies were performed prior to the procedure, and at 7 days, 6 months, 12 months, and 24 months after the procedure. We studied the following parameters: echo-score by the sum of valvular mobility, thickening, and calcification, and subvalvular disease, graded from 1 to 4; and mitral valve area (MVA) and mitral pressure gradient (MPG) by Doppler echocardiography. The patients were separated into two groups: group I with an echo-score less than or equal to 8 (40 patients), and group II with an echo-score greater than or equal to 9 (22 patients). Mitral valve area and MPG were compared with hemodynamics through the correlation coefficient and linear regression. Comparison between groups I and II was performed using the unpaired Student's t-test. Follow-up of MVA and MPG was analyzed by analysis of variance. The Student's t-test did not show any significant difference between MVA and MPG before balloon mitral valvotomy. There was significant decrease of MVA in group II (P less than 0.01) in the last three studies. There was significant increase in MPG in group II (P less than 0.01) in every postvalvotomy study. The analysis of variance of group I showed statistical increase of the MVA, and significant decrease of the MPG after BMV. The analysis of variance of group II showed significant increase in MVA and significant decrease in MPG between the pre- and the first postvalvotomy study. There was significant decrease (P less than 0.01) in MVA, and increase in MPG in the three postvalvotomy studies. Complications included mitral regurgitation, residual interatrial communication, pericardial effusion due to an atrial wall perforation, and peripheral embolization. Atrial fibrillation did not significantly alter the results of BMV. Results were considered positive when MVA was greater than 1.5 cm 2 and area increase was greater than 25%. Patients with an echo-score less than or equal to 8 (group I) benefit from BMV, with a positive predictive value greater than 78%. In pregnant patients the symptomatology was alleviated by BMV, without any signs of fetal compromise.
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