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Purpose: Prospective comparison of contrast-enhanced moving-table magnetic resonance (MR) angiography to catheter arteriography in endovascular and surgical treatment planning in patients with peripheral arterial occlusive disease., Materials and Methods: Thirteen patients scheduled for catheter arteriography for lower extremity arterial occlusive disease underwent contrast-enhanced moving-table MR angiography immediately prior to arteriography. A treatment plan was determined by the vascular surgeon, based on MR angiography, who was blinded to the catheter arteriogram. The treatment plan determined by the MR angiogram was compared to the final treatment plan, which was based on the catheter arteriogram and intraluminal pressure measurements., Results: Treatment plans based on MR angiography and catheter arteriography were identical in 10 of 13 patients (71%). For identifying lesions resulting in intervention, MR angiography had sensitivity of 100% and a positive predictive value of 92%. MR angiography had a treatment specific predictive value of 88% for each lesion identified, and 95% for lesions identified in patients evaluated for claudication. If treatment plans were based on MR angiography only, 46% of patients would have avoided catheter arteriography., Conclusion: Contrast-enhanced moving-table MR angiography may be an effective alternative to catheter arteriography in endovascular and surgical treatment planning in selected patients with peripheral arterial occlusive disease, but larger studies are necessary to confirm this.

Over a 14-month period at Boston City Hospital, 93 consecutive patients who had received a blunt or penetrating extremity injury in proximity to a major vascular structure were evaluated. All patients were totally asymptomatic and underwent arteriography for proximity as a sole indication. Twenty-seven patients (27%) were found to have abnormal arteriograms. Muscular branches of the profunda femoris artery were the most frequently injured arteries (28%). Arterial spasm (41%) was the most common radiographic finding. All patients were managed nonoperatively and followed closely by serial pulse examinations. Follow-up arteriography or duplex scanning was used in isolated cases. No patients in this study required operative intervention based on arteriographic findings. No patients have subsequently required operative intervention for delayed arterial abnormalities. Based on these findings we believe the use of arteriography for asymptomatic injuries in proximity to major vascular structures is unwarranted.

Preoperative angiography is widely used to estimate runoff before peripheral vascular bypass surgery. The Ad Hoc Committee on Reporting Standards for the Society for Vascular Surgery and the International Society for Cardiovascular Surgery recently proposed an angiographic scoring system that grades the quality of vessels distal to the proposed bypass site and calculates an overall runoff score after adjusting each vessel score by an arbitrary weighting factor. We compared this score with intraoperatively measured runoff resistance in 67 patients undergoing infrainguinal bypass. Correlation between overall runoff score and measured resistance varied with the distal bypass site and was reasonably predictive for femoropopliteal above-knee bypasses (r = 0.67, p = 0.004, N = 17) and femoroposterior tibial bypasses (r = 0.73, p = 0.03, N = 9), but not for femoropopliteal below-knee (r = 0.05, p = 0.76, N = 34) or femoroperoneal (r = 0.57, p = 0.18, N = 7) bypasses. When multiple linear regression was used to calculate the weighting factors (rather than using arbitrarily assigned factors), the correlation between overall angiogram score and measured resistance improved substantially for femoropopliteal above-knee (r = 0.85, p = 0.00006), femoropopliteal below-knee (r = 0.50, p = 0.03) and femoroperoneal (r = 0.83, p = 0.02) bypasses. Correlation for the entire group of 67 patients improved from r = 0.30 (p = 0.02) to r = 0.64 (p = 0.0001). We conclude that the committee's scoring system correlates with measured runoff resistance but can be improved by the use of multiple linear regression to calculate weighting factors for each vessel in the outflow tract.

The preoperative angiogram is widely used as a means of assessing peripheral vascular runoff before bypass grafting, but the correlation between preoperative angiographic findings and actual measurements of peripheral vascular resistance has not been adequately examined. To test this correlation, we first devised a simple technique for measuring peripheral resistance and validated it in five dogs. Increases in peripheral resistance were artificially produced by temporarily occluding either the deep or superficial femoral artery or by intravenous administration of phenylephrine hydrochloride, a vasoconstrictor. In each instance, significant increases in resistance could be measured. We then used a similar technique to measure resistance in 23 patients undergoing peripheral bypass surgery. In addition, preoperative angiograms for these 23 patients were independently scored by four readers as 0, 1, 2, or 3 based on the number of patent vessels seen below the knee. Variations in scoring from reader to reader suggested that the present criteria for grading angiograms on this basis are unclear. Moreover, the correlation between angiographic score and measured resistance was poor for three of the four scorers (-0.21 to -0.29, p greater than 0.05). The angiographic scores of one reader, however, correlated reasonably well with the peripheral resistance measured at surgery (-0.59, p = 0.01). These findings demonstrate that current criteria for grading the preoperative angiogram are not sufficiently standardized to reliably predict runoff from a preoperative angiogram. However, these findings also suggest that it may be possible to identify angiographic findings that correlate well with changes in measured resistance.

The preoperative angiogram is widely used to estimate runoff prior to infrainguinal bypass grafting, but the traditional method of angiographic scoring (0, 1, 2, or 3 based on the number of patent tibial vessels) correlates poorly with measurements of peripheral vascular resistance. We assigned a score of 0, 1, or 2 to each of four parameters (anterior and posterior tibial arteries [AT and PT], peroneal artery [PER], and plantar arch [ARCH]) on the preoperative angiograms of 39 patients admitted for elective femoral bypass grafting. These scores were then examined for their ability to correlate with the peripheral vascular resistance measured in each patient at the time of surgery. Multiple linear regression suggested that the scores assigned to the AT, PT, and ARCH were significantly correlated with observed resistance, but the PER subscore was not. Multiple linear regression of the AT, PT, and ARCH subscores suggested that resistance could be predicted from the equation: In (Resistance [mm Hg/ml/min]) = 0.786 - 0.268(AT) - 0.25(PT) - 0.358(ARCH), for which r = 0.78 and p less than 0.001. The ability of this relationship to predict resistance was tested by a division of the patient population into two roughly equal groups based on their observed resistance at surgery. When tested in this fashion, this equation had a sensitivity of 88% and a specificity of 82%. These findings suggest that the preoperative angiogram can be graded in a simple, yet unambiguous way, which allows a reasonable prediction of peripheral vascular resistance.