ABSTRACT
Objective To investigate the hemodynamic changes in a tortuous coronary to elucidate the effects of tortuosity on coronary perfusion and wall shear stress (WSS). Methods A single tortuous and non-tortuous patient-specific left anterior descending (LAD) coronary artery cases were selected. Two LAD models with and without coronary tortuosity were reconstructed in Mimics software and then transferred to the ANSYS Fluent software for performing computational fluid dynamics (CFD) simulation. The hemodynamic characteristics of both the LAD models were compared. Results The vessel WSS of the tortuous coronary artery clearly decreased in the bend section where the maximum curvature was larger than 1 mm-1.Such a scenario could led to an inadequate blood supply in the downstream vessels. A low WSS (0-26 Pa) acted on the outer wall of the bend, whereas the inner wall of the bend had a high WSS (>100 Pa). The mean WSS of the non-tortuous and tortuous models was 10.79 Pa and 36.12 Pa, respectively. The overall WSS of the tortuous model was larger compared with that of the non-tortuous model. Conclusions Coronary tortuosity increased the overall WSS, which could delay the progress of coronary atherosclerosis.
ABSTRACT
Objective To summarize the nursing methods for patients with chronic congestive heart failure treated with local renal nerve block. Methods 10 cases of patients with chronic congestive heart failure were treated with renal nerve block. The blood and urine electrolytes, plasma neuroendocrine hor-mones, the 24-hour urine volume were measured before and after the renal nerve block to calculate the rate of excretion of urinary sodium. The changes of the heart rate and blood pressure and the improvement of the dyspnoea, swelling and other symptoms of heart failure were monitored continuously before and after the re-nal nerve block. Results There was a significant increase in the 24-hour urine volume and the rate of excretion of urinary sodium in the patients with heart failure after the renal nerve block (P<0.05),and there was a significant decrease in the amount of plasma neuroendocrine hormones after the renal nerve block (P<0.01);there was no signifieant changes in the heart rate and the average blood pressure with improvement of dyspnoea, swelling and other symptoms of heart failure. No significant complications were found. Conclusions The nursing measures taken by the nurses in the clinical application of local renal nerve block as a new treatment modality to the treatment of patients with chronic congestive heart failure are safe, effective and feasible.
ABSTRACT
Objective To observe the clinical feasibility and effects of regional nerve blockade in patients with heart failure.Methods The study enrolled a total of 10 patients,age range from 55 to 75 years old(average 64?11 years old).The subject includes 8 males and 2 females,among which 6 cases were ischemic cardiomyopathy and 4 cases were dilated cardiomyopathy.All the patients met the criteria of NYHA class Ⅲ-Ⅳ heart function with heavy fluid load unresponsive to optimal medical therapy.Patients with diabetes and renal failure were ruled out from the study.After application of local anesthesia,15 mL of 0.25% Naropin was injected inside Gerota's fascia to achieve regional nerve blockade under CT guidance.Serum and urine electrolytes,neurohormones,renal clearance of sodium and 24-hour urine volume were recorded 24 h before and after the operation.Variartions in heart rate,blood pressure and symptons of dyspnea and edema were also under monitor.Results After nerve blockade,the 24-hour urine volume and renal sodium clearance increased obviously while the level of neurohormones decreased compared with that before operation.No obvious changes in heart rate and blood pressure were recorded and the symptons of heart failure were improved in the patients after operation. No complication was recorded in the study. Conclusion Regional nerve blockade may be a feasible,safe and effective treatment for congestive heart failure patients who do not respond well to the existing optimal medical therapy.