Shanahan Mx

Mechanisms of the development and resolution of paradoxical interventricular septal motion after uncomplicated cardiac surgery

Of 16 patients with normal preoperative left ventricular (LV) function studied by simultaneous two-dimensional and M-mode echocardiography before and after uncomplicated cardiac surgery, M-mode interventricular septal motion remained normal in seven (group I) and was paradoxical in nine (group II) 7 to 13 days postoperatively, but was normal in all 12 patients (7 group II) studied 3 to 18 months later. An abnormal systolic increase in normalized septal curvature, the essential feature of truly paradoxical septal motion, was not observed in either group during any study period (mean = 0.92 +/- 0.08), nor were significant differences found in septal thickening, LV fractional shortening, or fractional area change. In contrast, systolic anterior motion of the LV center increased from -0.1 +/- 1.6 mm preoperatively to 4.8 +/- 2.5 mm postoperatively in group II (p less than 0.001), and the LV posterior wall motion:thickening ratio increased from 1.10 +/- 0.33 to 2.16 +/- 0.45 (p less than 0.01), but both parameters had returned to preoperative levels at the follow-up study. Both parameters remained stable in group I during all study periods. In addition, direct intraoperative M-mode recordings (n = 14) demonstrated normal septal motion in both groups before chest closure, but esophageal echocardiograms (n = 10) demonstrated exaggerated anterior systolic LV motion within 2 hours of surgery in those from group II. Thus, early after uncomplicated cardiac surgery, apparently paradoxical septal motion relative to a fixed reference point is an artifact due to exaggerated cardiac mobility that resolves with the progressive restraining effect of postoperative adhesions.

Rationale for Simultaneous Carotid Endarterectomy and Aortocoronary Bypass

Seventy-eight patients were treated for coexistent carotid and coronary stenosis by simultaneous reconstructions. Five patients died (6.4%), one from a stroke contralateral to the carotid reconstruction. Four others suffered a perioperative stroke (total stroke incidence 6.4%). Three myocardial infarctions occurred (3.8%) including one fatal infarct. Analysis of the most recent 36 combined reconstructions indicates that the extramorbidity in this group increased the stroke or death rate for all carotid endarterectomies carried out in the same period by only 1%. Alternatively if these patients had been operated upon by aortocoronary grafting alone the mortality would have increased by 0.1% assuming no neurologic complications. Since these 36 patients had severe carotid stenosis and would have been refused carotid endarterectomy as an isolated procedure the results seem better than would have been achieved by staged operations.