Limitations of using arterial conduit for myocardial revascularization in patients with combined coronary and other arterial lesions.

To explore the limitations of using arterial conduit for myocardial revascularization in patients with combined coronary and other arterial lesions, we evaluated 195 patients with combined lesions undergoing CABG, either alone or in combination with peripheral vascular reconstruction between October 1987 to October 1990. Doppler flow and spectral analysis revealed that 14 patients (7.1%) had atherosclerotic lesions of the subclavian artery, in whom ipsilateral internal mammary artery pedicle graft was contraindicated for myocardial revascularization. Out of 195 patients, 165 patients were subjected for aortography, 18 of whom (10.9%), revealed atherosclerotic involvement of the celiac trunk, thereby contraindicating the use of gastroepiploic artery for myocardial revascularization. Thus in our experience use of arterial conduit for myocardial revascularization in patients with combined coronary and other arterial lesions is limited.

Antegrade and retrograde cardioplegia with different reperfusion techniques in patients with multiple coronary artery lesions.

To evaluate the effectiveness of retrograde cardioplegia and reperfusion, a total of 266 patients undergoing coronary bypass surgery between Nov 1987 to Dec 1989 were divided into three groups depending on the method of cardioplegic fluid delivery and reperfusion. In group I (80 patients) antegrade cardioplegia and reperfusion was used. In group II (98 patients) antegrade and retrograde cardioplegia and antegrade reperfusion was used while in group III antegrade and retrograde cardioplegia and retrograde reperfusion was used. Myocardial functions were studied with the help of an on-line computer on the basis of mathematical model of heart before and after cardiopulmonary bypass. Biopsy specimens were collected before, during and after cardiopulmonary bypass in order to study myocardial structural changes. In group I patients there was decrease in myocardial function in the immediate post perfusion period while group II patients had considerable improvement in their myocardial function and groups III patients showed further improvement in it. Ultrastructural myocardial study revealed considerable detrimental changes in group I, minimal changes in group II and no change in group III patients. Thus in our experience retrograde cardioplegia and retrograde reperfusion with warm oxygenated blood provide maximum myocardial protection in patients with multiple coronary artery lesions.