Early reperfusion strategy improves the outcomes of surgery for type A acute aortic dissection with malperfusion.

OBJECTIVE: The control of malperfusion is the key to improving the outcomes of surgery for type A acute aortic dissection. We revised our treatment strategy to reperfuse each ischemic organ before central repair. METHODS: Our current early reperfusion strategy consists of percutaneous coronary artery intervention for coronary malperfusion, direct surgical fenestration for carotid artery occlusion, active perfusion of the superior mesenteric artery for visceral malperfusion, and external shunting from the brachial artery to the femoral artery for lower limb ischemia. Central repair is performed without delay after reperfusion therapy, but if irreversible organ damage is recognized, further aggressive treatment is discontinued. RESULTS: Among 438 patients who underwent initial treatment for type A acute aortic dissection, malperfusion in one or more organs was diagnosed in 108 patients (24%). We applied an early reperfusion strategy in 33 patients, (coronary, 14 patients; carotid, 4; visceral, 7; lower extremity, 8). Central repair was then performed in 28 patients. One patient (3.6%) died of pneumonia; 27 patients overcame the ischemic organ damage and survived. Among the 108 patients with malperfusion, 10 patients (9.3%) were treated medically without early reperfusion and central repair. During the same period, mortality from central repair procedures in patients with malperfusion who had not received early reperfusion therapy was 12 of 65 (18%), and the mortality of patients without malperfusion was 9 of 262 (3.4%). Malperfusion was a serious risk factor for hospital death, but the mortality rate of the patients with an early reperfusion strategy was significantly (P < .01) lower than the patients without early reperfusion. CONCLUSIONS: Our strategy might improve the outcomes of surgery for type A acute aortic dissection with malperfusion. This strategy enables us to avoid unproductive central repair procedures in irreversibly damaged patients.

Estimation of cardiac function with rotary blood pump.

BACKGROUND: A rotary blood pump may be implanted as a bridge to cardiac transplantation. Also, mechanical, histological, and biochemical improvements have been described in cardiac function after the implantation of a left ventricular assists device (LVAD). Thus there is considerable enthusiasm that LVAD might be used as a bridge to the recovery of myocardial function. Unlike a pulsatile pump, however, we cannot stop the rotary blood pump to estimate cardiac function. If the rotary blood pump stops, back flow will occur. In this study, a new method was examined that can estimate cardiac function without stopping the pump. MATERIALS AND METHODS: Twelve pigs were subjected to this acute study. The pump was implanted as an LVAD with an inlet cannula inserted into the left ventricle and the outlet cannula into the ascending aorta. The assist ratio was changed to 75%, from 25%. The relationship between the dp/dt of the left ventricle pressure and the differentiated pump flow rate was examined. Also, cardiac function was changed by epinephrine loading to estimate this method under hyperdynamic heart conditions. RESULTS: There was high positive correlation between the dp/dt of left ventricle pressure and differentiated the pump flow rate to 75% assisted ratio, from 25%. This relationship was established under hyperdynamic conditions. CONCLUSION: This method is simple and useful for estimating the cardiac function without pump stoppage.