Postcatheterization injuries at the vascular access site include pseudoaneurysms and arteriovenous fistulas. Traditional treatment of this complication has been surgical repair. This study describes a recently developed method for closing femoral pseudoaneurysms and arteriovenous fistulas by using external compression guided by Doppler color flow imaging. Thirty-six femoral artery injuries (31 pseudoaneurysms, 5 arteriovenous fistulas) were detected by color flow imaging in 35 patients with enlarging groin hematomas and/or groin bruits. All patients underwent a full trial of compression therapy, with an extended compression time limit of 240 minutes and a tag-team approach of two operators to overcome manual fatiguing. The mechanical compression was titrated to obliterate the vascular tracts to the aneurysms or of the arteriovenous fistulas and to maintain an adequate flow in the femoral artery, as far as possible. All postangiographic pseudoaneurysms were successfully treated with a compression time ranging from 10 to 110 minutes, even in patients receiving prolonged anticoagulant therapy. Follow-up ultrasound examination the following morning and 4 to 5 days later confirmed a continued closure in all patients, without side effects such as venous thrombosis or ischemia. In arteriovenous fistulas, compression therapy was successful in two cases without complications or recurrences during follow-up. This study demonstrates that Doppler color flow ultrasound-guided compression of postangiographic femoral artery injuries is a safe and technically simple device and may be implemented as a cost-effective, first-line treatment, with a high rate of success in pseudoaneurysms.

In addition to further studies using Doppler catheters to assess blood flow velocity during coronary angioplasty this study intends to evaluate the functional significance of coronary stenoses and to estimate their hemodynamic relevance prior to and after percutaneous transluminal coronary angioplasty (PTCA). Diameters of coronary artery stenoses were quantified by means of the cardiovascular angiographic analysis system (CAAS) both prior to and following successful PTCA in 37 patients. During coronary artery angioplasty a 12 M:Hz 0.018-in. Doppler-tipped guidewire was used to measure prestenotic and poststenotic parameters of coronary artery flow velocity both prior to and following PTCA. The minimal stenosis diameter was raised from 1.01 +/- 0.58 to 1.76 +/- 0.73 mm (P < 0.0001), the percent diameter stenosis decreased from 63 +/- 11 to 35 +/- 6% (P < 0.0001). Prestenotic average (APV) and maximum peak velocity (MPV), peak velocity integral (PVI), average systolic (ASPV) and diastolic (ADPV) peak velocity, systolic (SPVI) and diastolic (DPVI) peak velocity integral, and diastolic/systolic velocity ratio showed--in contrast to further studies--a considerably significant difference (P < 0.05), whereas poststenotic Doppler data (APV, MPV, PVI, ASPV, DSPV, SPVI, DPVI, DSVR) differed highly significantly (P < 0.0001) prior to and following PTCA. Prestenotic and poststenotic measurements of coronary artery flow velocity differed significantly before and after PTCA and offer the potential for estimating both the hemodynamic relevance of coronary artery stenoses and success of PTCA.

Doppler probes mounted on the tip of a guidewire allow the measurement of coronary blood flow velocities, not only proximal but also distal to stenoses eligible for percutaneous transluminal coronary angioplasty (PTCA). The objective of this study was to determine the improvement of transstenotic Doppler flow velocity ratios following PTCA and to investigate the possible impact on restenosis during follow-up control angiography three months later. Doppler flow velocity measurements were performed in 29 patients with 29 stenoses eligible for PTCA. Results of PTCA were morphologically evaluated by computer-assisted quantitative coronary angiography (QCA) and measured hemodynamically by determining transstenotic Doppler flow velocity ratios. Successful PTCA according to QCA was present in all cases with a reduction of mean diameter stenosis from 66 +/- 8% to 35 +/- 7%. Resting spectral peak velocities and velocity integrals were markedly reduced distal to lesions (all P < 0.001), resulting in mean transstenotic flow velocity and velocity integral ratios of less than 0.60 prior to PTCA. Owing to endoluminal enlargement, significant improvement of transstenotic Doppler ratios was observed in mean ratios greater than 0.90 (all P < 0.0001). In patients with restenosis, transstenotic ratios following PTCA demonstrated a tendency to be smaller than in patients without restenosis. Transstenotic Doppler flow velocity ratios are diminished in severe coronary stenoses. Improvement of these ratios provides information on hemodynamic success of interventional procedures. Thus, the determination of intracoronary Doppler flow velocity ratios contributes, in addition to angiographic estimation, to the evaluation of stenoses severity and success of interventional procedures.

Summary:The angiocardiographic evaluation of left ventricular end-diastolic (LVEDV) and end-systolic (LVESV) volumes and ejection fraction (EF) is routinely performed by the area-length method (ALM) but may lead to erroneous results. Digital imaging in real time allows densitometric procedures of determining left ventricular (LV) performance to be applied alternatively. In this study, we present densitometric algorithms for the analysis of LVEDV, LVESV, and EF from digital image data, establish accuracy and reproducibility, *and determine value and limitations in comparison with ALM in single-plane 30" right anterior oblique (RAO) projection. A linear relationship between iodine depth and measured densities is mainly burdened with scatter radiation and beam hardening which reduce primary radiation and suppress iodine depth. However, facilities such as deconvolution and correction algorithms are capable of reducing these sources of error.In the present study, computer-analyzed contrast images of iodine-tilled wedges and spheres showed a near-linear relationship between iodine depth between 50-100 mg/cm' and measured densities. Contrast images of heart casts and LV angio-grams of 54 patients were obtained with a digital image acquisition and processing system, and evaluated by two in- The angiographic study of patients demonstrated significant correlations between both methods (LVEDV r = 0.78, LVESV r = 0.83, total volumes: r = 0.89; EF r = 0.88). The standard errors of estimate can be ascribed to systematic, method-related errors of both DENS and ALM (LVEDV k 28.9 ml, LVESV f 23.4 ml, total volumes (EDV and ESV) f 27.1 ml; EF & 8.1 %). The intra-and interobserver variability, respectively, exhibited significantly smaller (p 5 0.0 1 and p I 0.05, respectively) standard errors of estimate for densitometric EF [4.6% (DENS) vs. 8.5% (ALM) and 7.1% (DENS) vs. 10.3% (ALM), respectively]. Inclined but not significant differences were found for LVEDV and LVESV. In conclusion, the data presented indicate that the calculation of LV volumes and EF in digital left ventriculography may be performed accurately by densitometric calculation in single-plane 30" RAO projection. Minor underestimations in densitometric volume determination may be anticipated in the evaluation of LV geometry.

The purpose of this study was to investigate differences between prestenotic and poststenotic intracoronary Doppler flow velocities and to determine whether these hemodynamic parameters of coronary flow demonstrate a correlation with geometrically measured coronary artery stenosis.A low-profile (0.018-in.) Doppler angioplasty guidewire capable of providing spectral flow velocity data was used to measure blood flow velocities both proximal and distal of 95 coronary artery stenoses ranging from 15% to 82% in diameter. Percent diameter stenoses were analyzed by quantitative coronary arteriography.In comparison with prestenotic measurements poststenotic Doppler flow velocities were markedly reduced in coronary artery stenoses with a diameter reduction greater than 50% in quantitative angiography. In stenoses less than 50% no difference between prestenotic and poststenotic parameters of coronary flow could be found. Prestenotic Doppler data demonstrated no correlation to percent diameter stenosis, whereas poststenotic flow data correlated moderately with percent diameter stenosis. Poststenotic Doppler data of stenoses below 50% differed significantly from stenoses above 50%.In conclusion, intracoronary Doppler flow velocity measurements performed distal to coronary artery stenoses contribute to the evaluation of hemodynamic significances of particular coronary artery stenoses.