Background-Coronary collaterals are essential to maintain myocardial function in chronic total coronary occlusions (TCOs). The aim of the present study was to assess the collateral circulation in TCOs before coronary angioplasty and to determine the recruitable collateral perfusion after recanalization by use of intracoronary Doppler flow velocimetry. Methods and Results-In 21 patients with TCOs (duration Ͼ4 weeks), Doppler recordings of basal collateral flow were obtained before the first balloon inflation. Angioplasty was performed with stent implantation in all lesions. At the end of the procedure, recruitable collateral flow was measured during a repeat balloon inflation. The collateral flow index (CFI) was calculated from the velocity integral during the occlusion/velocity integral of antegrade flow. In 17 of 21 patients, angiography was repeated after 24 hours, and CFI was reassessed. Average peak velocity of collateral flow was 10.9Ϯ5.6 cm/s with a predominantly systolic flow (diastolic/systolic velocity ratio Ͻ0.5) compared with antegrade flow (diastolic/systolic velocity ratio Ͼ1.5). After recanalization, the average peak velocity of recruitable collateral flow dropped by Ͼ50% to 4.7Ϯ2.5 cm/s. CFI fell from 0.48Ϯ0.25 to 0.21Ϯ0.16 (PϽ0.001). There was no further change of CFI during the following 24 hours. CFI was higher in patients with preserved regional ventricular function than in those with akinetic myocardium (0.57Ϯ0.23 versus 0.38Ϯ0.12, PϽ0.05).
Conclusions-Collateral
Background-Collateral circulation can maintain myocardial function and viability in chronic total coronary occlusion (TCO). The present study evaluates the relation of myocardial function and duration of occlusion to collateral function. Methods and Results-A total of 50 patients underwent a successful recanalization of a TCO (Ͼ4 weeks' duration).Collateral function was assessed by intracoronary Doppler and pressure recordings before the first balloon inflation and after PTCA had been completed. Collateral function was assessed by Doppler-(CFI D ) and pressure-derived collateral flow indices (CFI P ), as well as indices of collateral (R Coll ) and peripheral resistance (R P ). Patients with normokinesia had lower R Coll (4.9Ϯ2.5 versus 11.8Ϯ8.2 mm Hg · cm Ϫ1 · s Ϫ1 ; Pϭ0.033) and lower R P (3.8Ϯ1.9 versus 6.1Ϯ4.1 mm Hg · cm Ϫ1 · s
To date, this is the largest prospective study with PCBs in small vessel de novo lesions in unselected patients. Rates of TLR and MACE were low, suggesting the use of PCBs may be an attractive alternative treatment option to drug eluting stents in small vessels.
Outer dense fibers (ODFs) are located on the outside of the axoneme in the midpiece and principal piece of the mammalian sperm tail and may help to maintain the passive elastic structures and elastic recoil of the sperm tail. We have identified and describe here a human gene that is homologous to the Mst(3)CGP gene family of Drosophila melanogaster and encodes an ODF protein of 241 amino acids. The transcribed region has a size of approximately 1 kb and contains two exons of 416 bp and 406 bp, respectively, not including the 3' untranslated region. The gene is expressed in testis but not in human spleen, kidney, or brain and resembles in this respect the expression of the Drosophila Mst(3)CGP gene family in the male germline. An antiserum raised against a synthetic peptide derived from the N-terminus of the encoded sequence identified a protein of approximately 32 kDa in an extract of human sperm flagella. By Southern-blot analyses and in situ hybridization, the ODF gene was localized to band q22 of chromosome 8. The isolation of a human gene encoding a sperm tail protein may provide the ability to identify and investigate, on the molecular level, possible reasons for human male infertility that are dependent on flagellar disturbances.
Background-Microvascular dysfunction is defined as reduced coronary flow reserve in the absence of an epicardial stenosis. This study determined its prevalence and relation to regional myocardial function in chronic total coronary occlusions (TCO). Methods and Results-After recanalization and stenting of a TCO (duration, Ͼ4 weeks) in 42 patients, coronary flow velocity reserve (CFVR) was measured by intracoronary Doppler. In a subset of 27 patients, intracoronary pressure was recorded to obtain the fractional flow reserve (FFR). In 21 patients, the CFVR was reassessed after 24 hours. CFVR was Ͻ2.0 in 55% of all patients. In the subgroup with simultaneous pressure recordings, 52% of patients showed a CFVRϽ2.0 and a FFRՆ0.
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