Influence of splenomegaly on aortic and liver parenchymal CT numbers during contrast-enhance CT in patients with cirrhosis.

INTRODUCTION: To compare CT (computed tomography) values for enhancement of the abdominal aorta and liver parenchyma during dynamic contrast enhancement (CE) CT in cirrhotic patients with and without splenomegaly (SM). METHODS: We considered 258 patients (83 males and 46 females for the splenomegaly group, and 83 males and 46 females for the control group) for this retrospective study. We measured CT values in the abdominal aorta and hepatic parenchyma during the hepatic arterial (HAP) and portal venous (PVP) phases. The aortic CE at HAP and the hepatic parenchymal CE at PVP were compared between the two groups. For success rate of scans, we also calculated the optimal CE rates (>280 HU in the abdominal aorta and >50 HU in the hepatic parenchyma) for each group. RESULTS: In the SM group, the CE for abdominal aorta was decreased during the aortic phase for a dynamic CE-CT (p < 0.05). When evaluating the success rates, they were found to be 65.1 % and 58.9 % in the SM group and 81.4 % and 72.3 % in the non-SM group (p < 0.05). CONCLUSION: The success rate of scans and CE for the abdominal aorta during the aortic phase exhibited a significant decrease during dynamic CE-CT scans on patients with SM. Patients with SM may have reduced diagnostic ability with typical contrast injection protocols. IMPLICATIONS FOR PRACTICE: It may be necessary to change the injection rates and contrast medium volume during CE-CT depending on the presence or absence of SM.

Improvement of cardiac function by short atrioventricular delay and diastolic mitral regurgitation in patients implanted with DDD pacemakers

Efficacy of short atrioventricular (AV) delay and diastolic mitral regurgitation (MR) were studied in 16 patients (70.2 mais ou menos 10.5 SD years old) with implanted DDD pacemakers. AV delay was set at 0.215 and 0.115 sec. In 10 of the 16 patients, diastolic MR was not observed when the AV delay was set at both 0.215 and 0.115 sec. Cardiac output (CO) and pulmonary capilary wedge pressure (PCWP) did not change.In 6 of the 16 patients, diastolic MR was observed when the AV delay was set a 0.215 se However, diastolic MR was not observed when the AV delay was set at 0.115 sec. CO increased from 3.6 mais ou menos 0.7 to 3.9 mais ou menos 0.8 I/min (p menor que 0.05). PCWP was decreased in 5 of the 6 patients (83 por cento, p menor que 0.05 vs. 10 por cento in patients without diastolic MR at 0.215 sec of AV delay). Cardiac function may be improved by shortening AV delay when the diastolic MR was observed. On the other hand, short AV delay may not be effective for patients in whom diastolic MR was ntobserved.