P1033Echocardiographic predictive model of new-onset postoperative atrial fibrillation after abdominal surgery.

BACKGROUND: and purpose: Postoperative atrial fibrillation (POAF) is a frequent complication post high-risk abdominal surgery in elderly patients. This study aimed to develop a predictive model of POAF based on preoperative transthoracic echocardiography (TTE) findings in these patients. METHODS: We conducted a prospective study of 300 consecutive patients, age ≥ 65 years (mean age 72±6 years, 61% men), who underwent high-risk abdominal surgery under general anesthesia. Preoperative TTE was performed in all patients, including tissue Doppler imaging (TDI). We measured the time interval between the onset of the P-wave on ECG and a point of the peak-A wave on TDI from the lateral mitral annulus (PA lateral) and septal mitral annulus (PA septal). Left atrial (LA) dyssynchrony was measured by subtracting the PA septal from PA lateral. Right ventricular systolic pressure was estimated by using the tricuspid regurgitation jet (TRJ) Doppler velocity method. The primary endpoint was the occurance of new-onset POAF. RESULTS: Thirty-seven (12%) patients developed POAF. Multiple echocardiographic parameters were measured and tested in different combinations. The final model included the following variables with cutoff points predictive of POAF: PA lateral > 139 ms (69% sensitivity, 92% specificity), LA dyssynchrony > 35 ms (78% sensitivity, 89% specificity), and TRJ Doppler velocity >2.6 m/s (89% sensitivity, 64% specificity). A value of 0 was assigned when the result was below the cutoff point and a value of 1 if above the cutoff point. Coding of these three variables in the following order: PA lateral- TRJ Doppler- left atrial dyssynchrony can predict the probability of POAF. The model showed a postive predictive value of 79% and a negative predictive value of 95%. CONCLUSION: A model using three echocardiographic variables: PA lateral, LA dyssynchrony and TRJ Doppler velocity, can predict the incidence of POAF after high-risk abdominal surgery. The model can be used preoperatively to identify high-risk patients that would need aggressive prophylactic treatment.PA lateral >139 ms-TRJ Doppler velocity >2.6 m/s-LA dyssynchrony >35 msProbability of POAF0- 0- 0; 0- 1- 0No0- 0- 1; 0- 1- 1; 1- 0- 0; 1- 0- 1; 1- 1- 0; 1- 1- 1Yes.

Experimental testicular torsion--early and late morphological and enzymohistochemical changes.

It has been reported that testicular torsion leads to diminished fertility. This experimental study includes 32 mature male Wistar rats, divided into 3 groups. Group 1 (4 animals) served as a control group. Group 2 (16 animals) underwent an unilateral definitive ligature of the testicular vessels. Group 3 (12 animals) underwent right testicular torsion at 360 degrees, followed by detorsion at 4, 12 or 24 hours. Both testicles were removed at different terms after the operation and processed for histologic and enzymohistochemical studies. The results of the experiment indicate that a certain recovery of the structure and the enzyme activity may be expected only in case if the duration of the torsion lasts not more than 4 hours. After this period severe and irreversible changes in the ipsilateral testis and serious alterations in the contralateral testis occur.

Polymeric pyelotomy (experimental studies).

A non-toxic, soluble polymeric preparation MAG with controlled period of gelation was synthetized for the extraction of stones from the pyelocalyceal system during surgery for urolithiasis. With respect to toughness the preparation proved superior to the fibrinogen-thrombin mixture, used in the so-called "fibrin pyelotomy" according to Dees. Its biologic testing in animals (rabbits, dogs and pigs) yielded excellent results.