Management of catheter-induced venous thrombosis

Catheter-induced venous thrombosis remains a significant problem in current clinical practice. A high level of biocompatibility of the materials used to manufacture the existing venous access devices has not eliminated catheter-induced venous thrombosis. Similarly, catheter bonding with anticoagulants or their systemic use, while in some instances having a favorable effect on the incidence, has not eliminated this problem. The focus of this article is on discussion of the various factors that influence formation of catheter-induced venous thrombosis. Also discussed is the management of this clinical problem, and a useful algorithm is outlined.     

Partial elective pancreatectomy is curative in focal form of permanent hyperinsulinemic hypoglycaemia in infancy: A report of 45 cases from 1983 to 2000

Background/Purpose: Permanent hyperinsulinemic hypoglycaemia in infancy (PHHI)I is a severe disease that leads to brain damage. Since 1989, pathologists have identified 2 different forms of the disease: a diffuse form (DiPHHI) and a focal form (FoPHHI). The purpose of this study was to adapt surgical techniques in case of FoPHHI to cure these infants without risk of diabetes. Methods: All patients with PHHI underwent pancreatic venous sampling (PVS) and elective partial pancreatectomy (EPP). Molecular biology and immunohistochemistry were used to ascertain that FoPHHI was a different disease from DiPHHI. Results: 45 EPPs were performed, guided by PVS and peroperative pathology. The lesions were 17 in the head, 4 in the isthmus, 6 in the body, 15 in the tail of the pancreas. Age at surgery ranged from 25 days to 4 years. Two patients already had been operated on elsewhere, and the focal lesion could be found at second operation. All 45 patients except one, were cured with euglycemia at both fasting and hyperglycaemic tests. Molecular biology has shown a specific anomaly in FoPHHI, which never has been encountered in DiPHHI. Conclusions: PHHI is not a homogeneous disease. In one third of cases, only a small amount of endocrine pancreas is abnormal, and conservative surgery is mandatory. The pre- and perioperative conditions to point out the focal pancreatic lesion are described.     

Is thyroid frozen section too much for too little?

BACKGROUND: The role of frozen section (FS) in thyroid disease is controversial. The goal of this study was to identify a cohort of patients who may or may not benefit from FS. METHODS: Two hundred thirty-one patients who underwent thyroidectomy were evaluated in regard to fine-needle aspiration (FNA), FS, and the extent of surgery. RESULTS: In all, 155 patients underwent FNA, 140 patients underwent FS, and 103 patients had both. A final diagnosis of malignancy was obtained in 47 of 231 patients. FNA had a sensitivity of 50% and a specificity of 99%, and FS had a sensitivity of 50% and a specificity of 100% for diagnosing malignancy. Accounting for the clinical findings and FNA results, FS results altered the extent of thyroidectomy in 1 of 103 patients. CONCLUSIONS: The increased costs for the operative time and the pathologists needed to obtain routine FS are not supported with any substantial benefit in patient outcome.     

Bronchial stenting and high-frequency percussive ventilation treatment of descending aortic aneurysm-induced atelectasis of the left lung

IMPLICATIONS: This case report shows that atelectasis of the left lung-induced by extrinsic compression of the left main bronchus by an aortic aneurysm and persisting despite aggressive conservative treatment-may be effectively treated by bronchial stenting and high-frequency percussive ventilation.     

Paravalvular leak and other events in silzone-coated mechanical heart valves: a report from AVERT

BACKGROUND: The Artificial Valve Endocarditis Reduction Trial (AVERT) was designed to compare endocarditis rates in Silzone versus conventional valves. Recruitment ended January 21, 2000, because of higher rates of paravalvular leakage in patients receiving the Silzone prosthesis. The present analysis determined late event rates that might be used in the management of approximately 36,000 patients who have received the Silzone prosthesis. METHODS: A total of 807 patients in 19 centers in North America and Europe were randomized. Mean age was 61+/-11 years; 41% were women. Operations included aortic valve replacement in 59%, mitral valve replacement in 32%, and aortic and mitral valve replacements in 9%; 41% had concomitant operations (26% coronary artery bypass grafting). RESULTS: Major paravalvular leakage (followed by repair, explant, or mortality) occurred in 18 of 403 patients receiving Silzone valves and 4 of 404 patients without Silzone valves (2-year event-free rates: 91.1% versus 98.9% conventional, p < 0.003). Similarly, 2-year freedom from any explant was lower in the Silzone arm (19 versus 2 events; 90.1% versus 99.4%, p = 0.0002). Rates of mortality and stroke were similar during follow-up. CONCLUSIONS: Continued follow-up of AVERT supports the conclusion that the Silzone prosthesis has increased risk of paravalvular leakage requiring reoperation. Overall survival is similar in the two groups.     

Epicardial ultrasound in off-pump coronary artery bypass grafting: potential aid in intraoperative coronary diagnostics

BACKGROUND: In off-pump coronary artery bypass surgery (OPCAB), epicardial ultrasound may aid in several intraoperative dilemmas. The aim of this study was to test a new mini-transducer for intraoperative coronary diagnostics. METHODS: A 10 MHz mini-transducer (15 x 6 x 9 mm) was applied epicardially in eight open chest and two closed chest porcine OPCAB procedures (using robotics) and on four postmortem human hearts. The transducer fitted in between the suction pods of the cardiac stabilizer and passed an 11-mm port. RESULTS: In the open chest cases the internal mammary arteries (including the side branches) could be visualized totally (n = 12). The left anterior descending coronary artery could be located over its entire course. Vascular anatomy, side branches, and septal perforators (diameter > or = 0.2 mm) could easily be discerned. In the closed chest cases the left anterior descending coronary artery, its side branches, and septal perforators could be visualized in both cases. In the postmortem human hearts the left anterior descending coronary artery could be visualized totally under the thick epicardial fibro-fatty layer and pathologic conditions could be identified. CONCLUSIONS: The 10 MHz ultrasound mini-transducer showed promise as a diagnostic tool in both open and closed chest coronary procedures on the beating heart.     

Transitory immunologic response after implantation of the DeBakey VAD continuous-axial-flow pump

BACKGROUND: The development of local and systemic infection is a significant risk factor associated with implantation of a ventricular assist device. The immunologic consequence of continuous-flow rotary blood pumps is not known. METHODS: Six male adult patients (mean age 47 plus minus 10.3) with end-stage left heart failure received a DeBakey VAD axial-flow pump for use as a bridge to transplantation. (Four patients underwent transplantation after a mean 115 plus minus 14 days; 2 patients are still waiting for the allograft.) RESULTS: We prospectively monitored T-cell populations and apoptosis-specific aberrant T-cell activation via CD95 triggering and annexin V binding to lymphocytes, identifying T cells undergoing early phases of apoptosis, within the first 10 weeks. Moreover, soluble death-inducing receptors soluble CD95 and soluble tumor necrosis factor-R1 were evaluated by enzyme-linked immunosorbent assay. CONCLUSION: Patients bridged to transplantation by a nonpulsatile ventricular assist device demonstrated an initial pronounced apoptosis-specific immune alteration by increased annexin V binding to CD3 T cells and death-inducing receptors soluble CD95/tumor necrosis factor-R1 (all P <.001). All parameters normalized after 7 weeks to baseline. No blood-borne sepsis was detected, as defined by blood culture, within the first 10 weeks of the cohort study. These results indicate a biphasic immunologic response in patients with end-stage heart failure treated with nonpulsatile ventricular assist devices.     

Calculated fast-growing benign prostatic hyperplasia--a risk factor for developing clinical prostate cancer

OBJECTIVE: Whether there is an association between the development of benign prostatic hyperplasia (BPH) and clinical prostate cancer is controversial. The present report tests the hypothesis of an association between BPH growth and the development of clinical prostate cancer by examining stage, grade and PSA-level in men with recently discovered clinical prostate cancer with slow or fast-growing BPH. If the hypothesis is true, men with fast-growing BPH would have a more advanced clinical prostate cancer. MATERIAL AND METHODS: Two hundred and twenty patients in whom a clinical prostate cancer was diagnosed were consecutively included. The prevalence of atherosclerotic disease, non-insulin-dependent diabetes mellitus (NIDDM) or treated hypertension was provided by the respective patient's medical history. Tallness, body weight, waist measurement, hip measurement and blood pressure were determined. The body mass index (BMI) and waist/hip ratio (WHR) were calculated. Blood samples were drawn to determine triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, uric acid, ALAT and the fasting plasma insulin level. The prostate gland volume was measured using transrectal ultrasound. The annual BPH growth rate was calculated, assuming that the total prostate gland volume was 20 mL at the patient age of forty. The prostate cancer diagnosis was established using the technique of transrectal ultrasound-guided automatic needle biopsy of the prostate. RESULTS: Men with clinical prostate cancer, PSA <50 ng/mL, and with fast-growing BPH had a higher systolic (p = 0.009) and diastolic (p = 0.020) blood pressure, were taller (p < 0.001) and more obese, as determined by body weight (p < 0.001), BMI (p = 0.005), waist measurement (p < 0.001) and hip measurement (p = 0.003). They also had a higher fasting plasma insulin level (p = 0.014) and a lower HDL-cholesterol level (p = 0.067) than men with slow-growing BPH. Moreover, men with clinical prostate cancer, PSA <50 ng/mL, and fast-growing BPH had more pronounced clinical prostate cancer, as measured by grade (p = 0.029) and PSA-level (p = 0.016), than men with slow-growing BPH. In the total material, including men with clinical prostate cancer, PSA >/=50 ng/mL, men with fast-growing BPH also had a higher prevalence of NIDDM (p = 0.039) and a borderline statistical significance for higher stage (p = 0.09) than men with slow-growing BPH. The BPH growth rate was significantly associated with the clinical prostate cancer grade (p = 0.018) and PSA-level (p = 0.002) but not with the clinical cancer stage in a multivariate statistical analysis. CONCLUSIONS: This report confirms findings in previous studies that fast-growing BPH is a risk factor for NIDDM, hypertension, tallness, obesity, dyslipidaemia and hyperinsulinaemia. The present report extends this list of risk factors to include atherosclerotic disease manifestations, hyperuricaemia and higher ALAT levels. The study suggests that fast-growing BPH is a risk factor for developing clinical prostate cancer and, thus, supports the hypothesis of an association between the development of BPH and clinical prostate cancer. The study generates the hypothesis that clinical prostate cancer is a component of the metabolic syndrome and that insulin is a promoter of clinical prostate cancer.     

Experimental evaluation and early clinical results of a new low-profile bileaflet aortic valve

We performed an experimental and clinical evaluation of a new low-profile bileaflet aortic valve (Regent, St. Jude Medical Inc., St. Paul, MN, U.S.A.). Common valve sizes were experimentally tested for leakage volume, pressure drop, and transvalvular hemodynamics using a pulse duplicator. Thirty patients (mean age 60 +/- 7 years, predominant valve stenosis n = 25) received the Regent prosthesis for initial clinical evaluation. In vitro evaluation revealed equivalent leakage volumes, larger performance indices (0.552 versus 0.513), and lower pressure drops in comparison to SJM hemodynamic plus valve controls. Clinically, 21 mm (n = 9), 23 mm (n = 12), and 25 mm (n = 9) valves were implanted with no significant perioperative complications. Echocardiography revealed low transvalvular flow velocities (2.2 +/- 0.4 m/s) and low pressure gradients (20 +/- 6 mm Hg) postoperatively and at 6 months follow-up. In vitro testing and early clinical results are promising; however, long-term performance has to be proven.