NONSURGICAL INFARCTECTOMY IN ACUTE EXPERIMENTAL MYOCARDIAL-INFARCTION

This study examines whether a catheter mounted left intraventricular b alloon may prevent left ventricular (LV) dysfunction following acute e xperimental myocardial infarction. In 10 anesthetized pigs, multiple c oronary arterial ligations were applied around the apex of the heart. LV end-diastolic pressure (LVEDP), aortic flow (AF), and LV long and s hort axis fractional shortening (FS) were measured before and at 15 mi n intervals after ligations. At the 60th min after ligation, the LV lo ng axis FS and AF decreased by 7.2 +/- 2.6% (p < 0.05) and 13.25 +/- 2 .68% (p < 0.01), respectively, and the LVEDP increased by 4.3 +/- 1.1 mm Hg (p < 0.01) while no change was noted in the LV short axis FS. An intraventricular catheter mounted nonpulsating balloon was positioned over the endocardium of the infarcted area at the LV apex. Inflation of the nonpulsating balloon to an optimal volume, which was found to b e equal to 8-10% of the LV end-diastolic volume, resulted in a reducti on (by 3.8 +/- 1.2 mm Hg, p < 0.01) of the already increased LVEDP and in an increase (by 6.6 +/- 2.1%, p < 0.05) in the LV short axis FS wh ile no statistically significant change was noted in the AF and LV lon g axis FS. It is concluded that an intraventricular catheter mounted b alloon patch positioned over the endocardium of the infarcted area may ameliorate early LV dysfunction, possibly by interfering with the fun ctional geometry of the LV contraction.