Intraoperative flow measurements in gastroepiploic grafts using pulsed Doppler 1

Abstract Objective: The patency of a pedicled right gastroepiploic artery (RGEA) graft can be compromised by intraoperative twists, kinks or spasms. Therefore, a systematic flow assessment was made in RGEA grafts and was compared with similar measurements made in other types of bypass conduits. Methods: Intraoperative pulsed Doppler flowmeter measurements obtained in a series of 556 consecutive patients undergoing at least one coronary bypass grafting onto the right coronary system were studied. Eighty-five RGEA grafts were compared with 1427 bypass grafts implanted in the same group of patients and consisted of the following conduits: 442 left internal mammary (LIMA), 149 right internal mammary (RIMA), 831 greater saphenous vein (GSV) and five inferior epigastric (EPIG) grafts. Sequential grafts were excluded from the analysis. Results: Flow measurements and Doppler waveforms were abnormal and required graft repositioning, and the addition of a distal graft or intragraft papaverine injection (only in GSVs) in 29 cases (2.0% of all grafts). These graft corrections were necessary in 5.9% RGEAs, 3.4% LIMAs, 2.0% RIMAs, and 0.7% GSVs (P Ͻ 0.001). The relative risk for graft correction was eight times higher for RGEAs than for GSVs (P = 0.002). Flow increased from 8 ± 2 to 54 ± 5 ml/min (P Ͻ 0.0001). Flow data were significantly influenced by the type of run-off bed (P Ͻ 0.001), the measurements obtained in grafts implanted onto the right coronary artery and the left anterior descending artery being superior. Flows in RGEAs, however, were comparable with values obtained in other grafts implanted onto the same recipient coronary artery. Conclusions: A significantly higher incidence of graft malpositioning caused inadequate flows in RGEAs. However, normal flow values could be restored simply by assigning a better graft orientation under pulsed Doppler flowmeter control. Overall flow capacity of the RGEA did not differ from values obtained in other arterial and venous grafts implanted onto the same recipient arteries

Does a concomitant Cox-maze procedure improve survival in atrial fibrillation?

In this review paper, the authors briefly describe the pathophysiology of atrial fibrillation. The original technique to restore sinus rhythm is cited, with its subsequent technical variations. A literature review summarizes the outcome of patients who benefited from the Cox-MAZE procedure

Towards better assessment and reduction of operative risk in coronary artery bypass grafting

The superiority of cold blood cardioplagie over crystalloid cardioplagia was extensievely confirmed by experimental and clinical data, a fact that was rarely disputed in the literature. The physiological advantage of blood cardioplagie resides less in its ability to deliver oxygen than in its buffering capacity, superior capillary flow distribution, potential for limitation of free radicals generations, preservation of endothelial function and reduction of hemodilution. Techniques of warm blood cardiopledia and normothermic cardiopulmonary bypass are more questionable and need further validation. Our initial experience with could blood cardioplegia was very convincing since the latter method reduced the negative influence of prolonged aortic cross-clamping on dysfunctional myocardium, was associated with a lower release of myocardial enzymes, and reduced markedly the volume of fluids administered perioperatively. We attempted of continuous retrograde administrations. A comparative study demonstrated that the latter method was appropriate in the clinical setting, reduced markedly the incidence of major adverse cardiac outcome and improved postoperative hemodynamicsThèse d'agrégation de l'enseignement supérieur (faculté de médecine) -- UCL, 199

La constitution d'une banque d'homogreffes de veines saphènes strippées est-elle possible?

The long-term cryopreservation of viable human venous allografts is discussed. The preservation technique includes immersion in a 15 p. cent Dimethylsulfoxide solution, followed by deep hypothermia in liquid nitrogen at - 196 degrees C. The veins studied were preserved for a period of 1 week to 24 months. Histological and scan electron microscopy examination does not show any specific alteration resulting from the freezing technique. Tissue enzymes assays, titration of the fibrinolytic activity and the rate of prostaglandins synthesis, are not affected by the duration of the preservation period. This cryopreservation technique respects the venous structure and functions; therefore, its clinical use is possible. Strict selection of the stripped veins according to morphological criteria seems therefore absolutely necessary

Emergency hepato-renal artery bypass using a PTFE graft.

A 51-year-old patient suffering from Buerger's disease with bilateral lower limb amputation and Leriche syndrome presented with uncontrollable hypertension and renal failure caused by right renal artery subocclusive stenosis associated with an occluded left renal artery and atrophic kidney. He underwent a right hepato-renal bypass grafting using an externally supported polytetrafluorethylene (PTFE) graft. Renal function improved markedly and hypertension could be controlled by standard antihypertensive treatment. Normal right renal function was maintained at one-year follow-up

Off-pump myocardial revascularization for left main stem disease in a high-risk patient.

Off-pump complete myocardial revascularization for three-vessel disease is often limited by the difficulty to approach the obtuse marginal branches. A method of coronary artery bypass grafting without cardiopulmonary bypass used in a high risk patient with left main stem and three-vessel disease is described

Do coronary bypass graft flows differ between on-pump and off-pump operations?

BACKGROUND: The aim of this study is to compare hemodynamic factors in coronary bypass grafts on-pump and off-pump. METHODS: Two propensity score-matched groups of 89 patients each including 408 dual beam Doppler flow measurements were compared. The study included only patent and single terminolateral bypass grafts. RESULTS: Flow was 64.9 +/- 37.3 mL/min in the on-pump group versus 58.6 +/- 35.0 mL/min in the off-pump group (p = 0.063); velocity was 23.8 +/- 10.5 versus 20.5 +/- 10.4 cm/s (p = 0.004); resistance measured as mm Hg/(mL/min(-1)) was 1.50 +/- 1.09 versus 1.76 +/- 1.14 (p = 0.020); pulsatility index was 1.98 +/- 1.52 versus 2.44 +/- 1.62 (p = 0.004). The hematocrit was 23.5 +/- 3.8% in the on-pump and 32.9 +/- 4.1% in the off-pump groups (p < 0 0.001). Multivariate analysis showed that hematocrit was the most significant factor influencing flow (p < 0.001) and velocity (p < 0.001), along with resistance (p = 0.004) and pulsatility index (p < 0.001). In a subset of 50 hemodynamic measurements made on left internal thoracic arteries implanted onto left anterior descending arteries and matched for hematocrit, there were no differences between on-pump and off-pump groups regarding flow, velocity, resistance, or pulsatility index. CONCLUSIONS: Off-pump compared with on-pump bypass surgery is associated with lower velocity and higher resistance in the grafts, mainly caused by changes in hematocrit and viscosity related to hemodilution

Successful Cox-maze III procedure combined with mitral valve replacement in a massively thrombosed left atrium.

A case is reported of chronic atrial fibrillation resulting from long-standing rheumatic mitral stenosis complicated by a massively thrombosed left atrium. In this patient, restoration of sinus rhythm and atrial transport function was performed using a Cox-maze III procedure with mitral valve replacement

Radiofrequency ablation of atrial flutter combined with closure of atrial septal defect.

Radiofrequency ablation of atrial flutter combined with patch closure of an atrial septal defect is described. Radiofrequency energy was delivered in the cavo-tricuspid isthmus and from the inferior margin of the atriotomy down to the septal defect using a temperature-controlled multipolar radiofrequency catheter. In addition, cryolesions were applied to the junction of the ablation scar with the tricuspid annulus and with the ostium of the inferior vena cava. Sinus rhythm was restored and an electrophysiologic study conducted 2 months later confirmed the bidirectional conduction block of the cavo-tricuspid isthmus