Improvement of coronary artery fistula surgery by intraoperative imaging.

Complete surgical closure of coronary artery fistulas may be difficult because of complex anatomy and often multiple sites of origin. This study therefore assessed whether intraoperative fistula imaging would contribute to and improve the final surgical result. Seven adult patients underwent operation for coronary arteriovenous fistula during a 10-year period. In all 4 patients who had image guidance, the operation was guided by immediate imaging to achieve complete and persistent closure. In contrast, 2 of 3 patients who underwent operation without image guidance had residual left-to-right shunts at follow-up. Image guidance was helpful and increased the success rate of surgical closure of coronary artery fistulas.

Intraoperative angiography leads to graft revision in coronary artery bypass surgery.

BACKGROUND: Graft anastomosis quality in coronary artery bypass surgery can be assessed by intraoperative angiography. The aim of the present study was to quantify the on-table revision rate initiated by intraoperative angiography. METHODS: Intraoperative angiography was carried out in 186 patients undergoing coronary artery bypass surgery, with a total of 427 grafts. The operation was performed on-pump in 34%, off-pump through a sternotomy in 49%, and as a minimally invasive direct coronary bypass grafting (MIDCAB) procedure in 17%. The angiography was performed intraoperatively while the patients were still in general anesthesia, with the possibility for on-table revision. Follow-up angiography was carried out after a mean of 346 days. RESULTS: Eighteen of 427 grafts (4.2%) were revised due to the findings at intraoperative angiography. Revision rate after on-pump surgery was 1.1%, after off-pump through a sternotomy 6.4%, and after MIDCAB 6.5%. In 6 patients the lesions were located at the distal anastomoses and in 12 patients in the conduit. All but one was successfully revised, and at 1-year follow-up all these 17 grafts were patent. CONCLUSIONS: Intraoperative angiography saves a potential number of grafts that otherwise could have been occluded. An increased implementation of intraoperative quality assessment in coronary artery bypass surgery can lead to improved outcome.

Clinical and Angiographic Outcome of Coronary Surgery with and without Cardiopulmonary Bypass: A Prospective Randomized Trial.

Abstract Background: Off-pump coronary artery bypass surgery has emerged as an alternative technique to traditional onpump surgery. The aim of this randomized study was to compare perioperative morbidity and mortality and intraoperative and short-term graft patency in off-pump and on-pump coronary artery bypass grafting. Methods: One hundred twenty patients were randomized for coronary revascularization with or without cardiopulmonary bypass. In all patients grafts and anastomoses were monitored with transit time Doppler ultrasonography and angiography. Angiography was repeated 3 months after the procedure in 115 of the patients. Results: Angiography 3 months postoperatively revealed that internal mammary artery patency was 98% in both groups. Vein graft patency was 83% in the off-pump group and 91% in the on-pump group, a difference that was not statistically significant. One perioperative death was recorded in each group. Two strokes were recorded in the on-pump group, none in the off-pump group. Conclusion: In this prospective, controlled study, perioperative and short-term outcome of off-pump coronary surgery equaled that of on-pump surgery.

The importance of intraoperative angiographic findings for predicting long-term patency in coronary artery bypass operations.

BACKGROUND: The quality of anastomosis is the cornerstone in coronary artery bypass operations. Intraoperative coronary angiography confirms graft patency with the possibility to revise graft failure. The aim of this study was to describe the lesions found at "on-table" angiography, and to evaluate the significance of these immediate angiographic findings for the long-term patency. METHODS: A total of 57 grafts (42 left internal mammary artery grafts and 15 saphenous vein grafts) in 45 patients who underwent off-pump coronary artery bypass operations were included. On-table angiography was carried out with fixed angiographic equipment installed in the operating room. Follow-up angiographies were performed at 3 months and at 12 months. RESULTS: The most frequent finding in an on-table angiogram was spasm, which was not present at follow-up. Out of nine kinks, only one developed into a significant stenosis at follow-up. Of 44 grafts that were normal on-table, 37 (84%) were normal at the follow-up. Of 11 grafts with significant lesions on-table, eight (73%) were normal at the follow-up. Five percent of the grafts were revised because of the on-table angiography. CONCLUSIONS: On-table angiograms can be occasionally difficult to interpret because not all findings are important for later patency. Optimal results on-table predict good long-term results with a negative predictive value of 0.84, whereas significant lesions on-table have less impact on the follow-up results because the positive predictive value was only 0.38.

Quantification of left ventricular diastolic pressure-volume relations during routine cardiac catheterization by two-dimensional digital echo quantification and left ventricular micromanometer.

BACKGROUND: Currently there is no simple clinical method for quantifying the left ventricular (LV) diastolic pressure-volume relation. Echocardiographic-automated endocardial border detection, however, may be combined with LV micromanometer to construct LV pressure-volume loops. We investigated the feasibility of on-line display and sampling of LV pressure-volume loops by such an approach. For this purpose we used a new echocardiographic digital echo quantification (DEQ) method in combination with LV pressures on-line and in real-time. METHODS: Eighteen patients were screened by conventional echocardiography and DEQ. Ten of the patients with high quality images were included in the study. Left ventricular pressures and volumes were recorded simultaneously and were displayed on-line as pressure-volume loops. Changes in LV volume were induced by intravenous saline. Left ventricular chamber compliance was estimated as change in volume divided by change in pressure from minimum diastolic pressure to end-diastolic pressure (average LV chamber compliance). RESULTS: Left ventricular pressure-volume loops were displayed on-line during the examination. When compared with the Simpson's method, DEQ underestimated end-diastolic volume (EDV) by 35% and overestimated end-systolic volume (ESV) by 14%. Beat-to-beat variability for ESV and EDV were 7.4% +/- 0.8% and 7.2% +/- 0.7 %, respectively. Volume loading increased LV end-diastolic pressure (LVEDP) from 14.0 +/- 1.6 to 24.7 +/- 2.0 mm Hg (P <.05) and EDV from 79 +/- 10 to 85 +/- 11 mL (NS), and decreased LV chamber compliance from 4.0 +/- 0.7 to 2.0 +/- 0.3 mL/mm Hg (P <.05). CONCLUSION: The current study demonstrates that LV pressure-volume loops can be displayed and evaluated in real-time during routine cardiac catheterization. This may represent a clinically useful method for identifying patients with reduced chamber compliance. The underestimation of the volumes by DEQ compared with the Simpson's method suggests that further refinements should be performed to improve the endocardial border detection algorithm.