Surgical treatment of active prosthetic valve endocarditis. Results in 66 patients

The results of combined medical and surgical management of 66 patients with active prosthetic valve endocarditis (APVE) are analyzed. Between 1970 and 1985, 3510 patients were operative survivors of mitral, aortic or double mitral-aortic valve replacement. Cumulative follow-up was 15,640 patient-years (mean 4.4 years). The overall annual incidence of reoperation for APVE was 0.42 +/- 0.05% (0.34 +/- 0.08% for biological and 0.46 +/- 0.06% for mechanical prostheses, p = n.s.). Early APVE occurred in 21 patients and 45 patients had late APVE. Indications for surgery were heart failure in 92%, systemic emboli in 5% and persistent sepsis in 3% of patients. Overall operative mortality (less than 30 days) was 38% (25/66). (Early APVE 52% and late APVE 31%). Anatomical location, valve design and number of prostheses implanted did not correlate with a higher operative risk. Overall endocarditis-related mortality was 56% (37/66). Uni and multivariate stepwise logistic regression analysis identified: 1) date of surgery (p = 0.01), 2) renal failure (p = 0.03) and 3) early APVE (p = 0.03) as predictors of endocarditis-related death. Actuarial survival at 1, 5 and 10 postoperative years was 41 +/- 6%, 30 +/- 6% and 24 +/- 7% respectively. This study confirms the high lethality of APVE. However, with adequate and aggressive combined medical and surgical management, some patients can be saved.     

Zero-Order Release Formulation of Oxprenolol Hydrochloride with Swelling and Erosion Control

Zero-order release of oxprenolol hydrochloride was obtained by controlling the swelling and erosion of the matrix. This formulation involves only mixing of drug, hydroxypropylmethylcellulose (HPMC), and sodium carboxymethylcellulose (Na CMC) at the ratio of 1:0.4:1.6, respectively, and compressing the mixture directly into tablets. The in vitro release pattern from this optimized matrix tablet was reproducible. Accelerated stability studies revealed that the optimized formulation remains stable for an approximately 2-year shelf life. This sustained-release (SR) tablet was evaluated in dogs, and for comparison a conventional (CV) formulation was also given at the same dose level. Plasma oxprenolol levels were monitored by a sensitive and specific high-performance liquid chromatographic (HPLC) method. Significant differences in the pharmacokinetic parameters, i.e., lower C _max, higher values of t _max, MRT, AUC, and plasma concentration at 24 hr, and nearly constant plasma levels over 12 hr, indicated that the SR matrix tablet is superior to the CV rapid-releasing formulation. The in vitro release parameters and in vivo pharmacokinetics correlated well.     

Venous valves in subclavian and internal jugular veins. Frequency, position, and structure in 100 autopsy cases

Valves in the subclavian and internal jugular veins were studied in 100 autopsy cases (52 men and 48 women; range, 18 to 91 years old; mean, 67 years). In 87 cases, valves were present in all 4 veins, and in 13 cases, valves anatomically were absent from 16 veins, 9 of which were the left internal jugular vein. The average distance from the valve to the junction with the innominate vein was 1.7 cm for the subclavian vein and 0.3 cm for the internal jugular vein. Cuspid height averaged 0.9 cm. Valves were bicuspid in 347 (90%) and unicuspid in 39 (10%); unicuspid valves were more common in the internal jugular vein than in the subclavian vein. Catheter-induced trauma was observed in 4 cases and implied in 4 more. These findings may have important implications concerning the failure, in some cases, of closed-chest cardiac resuscitation to maintain forward blood flow at adequate pressure.     

Walking after stroke. Measurement and recovery over the first 3 months

Sixty surviving patients had their walking ability and speed assessed regularly over the first 3 months after an acute stroke. Sixty-four matched controls were studied to allow categorisation of speed as 'slow' or 'normal'. Fourteen patients never had any significant loss of walking speed; fifteen patients never recovered the ability to walk and one patient remained dependent upon verbal support. Of the 30 showing significant recovery, only 10 regained normal speed, and 8 remained dependent upon a physical aid at 3 months. Plotting individual recovery curves of walking speed over time showed the wide range of change which may be expected. It is argued that timing of gait over 10 metres is a valid reliable measure that is currently underused.     

Imipenem/cilastatin therapy of infections in cancer patients

Imipenem/cilastatin was administered during 153 febrile episodes occurring in cancer patients and the response rate was 68%. Considering only documented infections the response rate was 71%. Patients who received imipenem as initial therapy had a higher response rate than patients who received it after failing other antibiotics (77% versus 68%). The overall response rates for septicemias and pneumonias were 75% and 58%. Among the 57 gram-negative infections 77% responded, but the response rate was substantially higher if imipenem was used as initial therapy (94% versus 69%). The poorest response rate was observed when imipenem was given as secondary therapy for Pseudomonas infections (50%), but most of these patients had failed to respond to other appropriate antibiotics. The only serious side effect was seizures which occurred in ten patients, although eight of them had other predisposing factors. Imipenem appears to be a useful antibiotic for treatment of infections, even in neutropenic cancer patients.