The Prognostic Value of Right Ventricular Function in Patients with Chronic Heart Failure-A Prospective Study

Background: In patients with stable chronic heart failure with a reduced ejection fraction (HFrEF), left ventricular ejection fraction (LVEF) provides limited prognostic value, especially in patients with moderately to severely reduced LVEF. Echocardiographic parameters of right ventricular function may be associated with adverse clinical events in these patients. Therefore, we analyzed 164 patients with HFrEF in a prospective single-center cohort study to evaluate whether the parameters of right ventricular function are associated with worsening heart failure (WHF) hospitalizations, cardiovascular and all-cause deaths and combined endpoints. Methods: Echocardiographic cine loops were analyzed using vendor-independent post-processing software. Multivariate Cox regression analyses were performed, which were then adjusted for clinical characteristics and left ventricular functional parameters. Results: In these models, higher tricuspid annular plane systolic excursion (TAPSE) was significantly associated with lower rates of WHF hospitalizations (HR 0.880, 95%CI 0.800-0.968, p = 0.008), a composite endpoint of WHF hospitalizations and cardiovascular death (HR 0.878, 95%CI 0.800-0.964, p = 0.006), and a composite endpoint of WHF hospitalization and all-cause death (HR 0.918, 95%CI 0.853-0.988, p = 0.023). These associations were more pronounced in patients with LVEF ≤ 35%. Conclusions: In conclusion, in patients with HFrEF, TAPSE is an independent prognosticator for adverse clinical outcomes, warranting further studies to elucidate whether incorporating TAPSE into established risk scores improves their diagnostic accuracy.

Prevalence and prognostic impact of bone disease in chronic heart failure with reduced ejection fraction

AIMS

Chronic heart failure is associated with a bone-catabolic state and increases the risk of osteoporosis and fractures. Prospective studies investigating the clinical relevance of bone disease in heart failure are lacking. We aimed to assess the prevalence and prognostic impact of osteoporosis and vertebral fractures (VFs) in chronic heart failure with reduced ejection fraction (HFrEF).

METHODS AND RESULTS

Symptomatic outpatients with chronic heart failure and a previous diagnosis of overtly reduced left ventricular ejection fraction < 40% on stable, optimal HFrEF therapy and left ventricular ejection fraction < 50% at enrolment were included into a prospective single-centre study. Osteoporosis was determined with dual-energy X-ray absorptiometry and defined as a T-score ≤ 2.5 at any site. VFs were assessed using X-ray of both thoracic and lumbar spine applying the semiquantitative Genant score. We enrolled 205 patients (22% women), with a median age of 66 (IQR 58-74) years. Median left ventricular ejection fraction was 37 (IQR 30-43) % and median N-terminal pro B-type natriuretic peptide was 964 (IQR 363-2173) pg/mL. Osteoporosis, as defined by bone mineral density, and at least one VF were prevalent in 31 (15%) and 29 patients (14%). Osteoporosis or VF were present in 55 patients (27%) and 5 patients (2%) had both osteoporosis and a VF. During a median follow-up of 4.7 (IQR 4.0-5.3) years, 18 patients (9%) died due to cardiovascular (CV) cause, and 46 patients (22%) had a worsening heart failure (WHF) hospitalization. In multivariate Cox regression analyses, presence of VF independently predicted CV death (HR 2.82, 95% CI 1.04-7.65, P = 0.042), WHF hospitalizations (HR 2.39, 95% CI 1.18-4.82, P = 0.015), and a composite endpoint of CV death and WHF hospitalizations (HR 2.44, 95% CI 1.23-4.82, P = 0.011). Osteoporosis was not significantly associated with CV events.

CONCLUSIONS

In a prospective study, bone disease affected every fourth patient with HFrEF, and patients with VF at baseline had a two-fold risk of subsequent CV death or WHF hospitalization. Prevalent bone disease, particularly VF, should be considered as a clinically relevant comorbidity in HFrEF.

Characterization of Flow-Caused Intrarenal Pressure Conditions During Percutaneous Nephrolithotomy In Vitro

PURPOSE

To investigate renal pelvic pressures during percutaneous nephrolithotomy (PCNL) in the standard, mini, and ultramini PCNL systems.

METHODS

We studied an ultramini PCNL system (UMP, outer shaft diameter 13F), a mini PCNL system (MPCNL, shaft 18F, nephroscope 12F), and a standard PCNL system (SPCNL, shaft 27F, nephroscope 24F). Pressure profiles were first investigated in an open model setup, subsequently in a closed model, and finally in an ex vivo porcine kidney. Measurements were determined with the nephroscope in an advanced and pulled-back position for all models.

RESULTS

In the advanced position, maximum pressures of 41.61 ± 0.20 mmHg (UMP), 15.61 ± 0.15 mmHg (MPCNL), and 15.46 ± 0.14 mmHg (SPCNL) were measured in the closed model. In the pulled-back position, maximum pressures were 16.04 ± 0.22 mmHg (UMP), 17.02 ± 0.11 mmHg (MPCNL), and 20.50 ± 0.11 mmHg (SPCNL). In the ex vivo porcine kidney model, maximum pressures were 13.81 ± 6.04 mmHg (UMP), 5.64 ± 0.21 (MPCNL), and 9.21 ± 0.52 (SPCNL) with the nephroscope pushed to end position. After retracting the nephroscope from the outer shaft, pressures in all systems did not exceed 10 mmHg.

CONCLUSIONS

The maximum pressures achieved with the three PCNL systems in all three models were kept below the 30 mmHg critical threshold value. High pressures were only determined for the UMP system with the nephroscope pushed to its end position. This was attributed to the conical shape of the nephroscope, which occupies the space between the nephroscope and outer shaft, resulting in outflow obstruction.

Feeding patterns of three sympatric tsetse species (Glossina spp.) (Diptera: Glossinidae) in the preforest zone of Côte d'Ivoire

The feeding patterns of Glossina longipalpis Wiedemann 1830, G. medicorum Austen 1911, G. palpalis gambiensis Vanderplank 1949 and G. p. palpalis Robineau-Desvoidy 1830 are described from natural habitats in central Côte d'Ivoire where these tsetse species occurred sympatrically. Blood-meal identification of tsetse flies revealed that in natural habitats wild ruminants were by far the most frequent source of food for each Glossina species, but there were significant differences between the nutritional spectra of single fly species. G. p. gambiensis fed significantly less often on bushbuck and significantly more often on monitor lizard (Varamus niloticus) than both, G. longipalpis and G. medicorum. In G. p. gambiensis the blood of wild ruminant species was significantly more often found than in G. p. palpalis, whereas the latter fed significantly more often on domestic animals. Peridomestic populations of G. longipalpis and G. p. palpalis fed mostly on domestic pig and therefore had significantly reduced host spectra in comparison to natural populations. The significant differences in feeding patterns among the investigated species, subspecies and populations seem not to depend on species specific feeding preferences. Rather, they can be attributed to microhabitat specialization of the various tsetse groups and hence mainly to the different availability of hosts. This implies that environmental factors should be taken more into account when analysing and comparing the feeding patterns of tsetse.

Natural host odours as possible attractants for Glossina tachinoides and G. longipalpis (Diptera: Glossinidae)

As strictly haematophagous insects, tsetse flies feed on a wide variety of wild and domestic animals. Although these are mainly mammals, some tsetse species also feed on reptiles. The present study investigated whether the odours of several potential natural tsetse hosts may be used as novel attractants to improve the catch of Glossina tachinoides or G. longipalpis in biconical traps. The odour of a living monitor lizard (Varanus niloticus) had no effect on the catch of G. tachinoides. Hexane skin washings of monitor lizard and warthog (Phacochoerus aethiopicus) dispensed in small quantities improved the catch of G. tachinoides significantly by factors of up to 1.34 and 1.46, respectively. Skin washing of bushbuck (Tragelaphus scriptus) did not increase the catch of G. tachinoides, but the synthetic phenolic fraction of bushbuck urine enhanced it significantly by 1.81 times. The catch of G. longipalpis was improved significantly by the urines of warthog, domestic pig and bushbuck by factors of 1.58, 1.91 and 2.51, respectively. In relation to the quantity of evaporated odour, bushbuck and warthog urine seem to be of particular interest for further attractant studies. The effect of tested host odours on the catch of G. tachinoides and G. longipalpis is compared with data of other tsetse species and with the frequency these hosts are fed on by tsetse flies. Bushbuck is one of the principal natural hosts of both Glossina species investigated, and of all odours tested, bushbuck urine and its synthetic phenolic fraction improved the catch of both tsetse species the most.

New cineromycins and musacins obtained by metabolite pattern analysis of Streptomyces griseoviridis (FH-S 1832). II. Structure elucidation

A detailed analysis of the secondary metabolite pattern produced by Streptomyces griseoviridis (strain FH-S 1832) using a chemical screening method resulted in the detection, isolation and structure elucidation of new 14-membered lactones of the cineromycin B-type [dehydrocineromycin B (5), oxycineromycin B (7), and 2,3-dihydrocineromycin B (8)], as well as new gamma-lactones related to nigrosporalactone and 4,5-dihydroxy-octa-2,6-dienoic acid esters named musacins A to F (10, 13 approximately 15, 17, 18 and 21). The constitution of these metabolites were deduced from spectroscopic data as well as chemical transformations. The configuration of musacin D (10) was determined by derivatization with chiral acids (Helmchen's method).

Production and characterization of anti-human interferon gamma receptor antibody fragments that inhibit cytokine binding to the receptor

Three single-chain antibody fragments that recognize the extracellular human interferon gamma receptor alpha-chain (IFN gamma R), and inhibit the binding of human IFN gamma, have been produced in Escherichia coli. These fragments are derived from murine anti-receptor monoclonal antibodies, and comprise the variable heavy (VH) domain linked to the variable light (VL) chain through a 15 amino acid linker [(GGGGS)3]. Using surface plasmon resonance technology (BIAcore), the soluble proteins were shown to retain a high affinity for recombinant IFN gamma R, and by radioimmunoassay to possess a high inhibitory activity towards IFN gamma-binding to human Raji cells. The antibody fragments most likely recognize epitopes that overlap the cytokine binding site on the receptor surface. Attempts to dissect further the antibodies to isolated VH- and VL-chains and to synthetic linear and cyclic peptides derived from the individual complementarity determining regions failed to afford fragments with significant IFN gamma R binding affinity. Nevertheless, these native-like variable region fragments and petidomimetics derived from them are of interest in the design of novel IFN gamma R antagonists.

Olfactory attractants for West African tsetse flies, glossina spp. (Diptera: Glossinidae)

The effect of various natural host odours on Glossina longipalpis, G. medicorum and G. tachinoides from catches in odour-baited biconical traps was analysed. Substances tested were ox urine, and the eight components of its phenolic fraction, as well as acetone and 1-octen-3-ol, both of which are present in ox breath. Ox urine increased the catch of G. tachinoides significantly by 1.2 times. Its phenolic fraction gave increases of up to 1.6 for G. longipalpis and 1.4 for G. tachinoides (significant in both cases). Adding acetone and/or 1-octen-3-ol to the phenolic fraction increased attraction of G. longipalpis and G. tachinoides significantly by up to 1.8 and 1.3 times, respectively. Octenol on its own increased the catch of all three species significantly by up to 2.2 times. Acetone alone, in combination with octenol or with the phenolic fraction reduced the catch of G. medicorum significantly to a level of 0.2. 3-Methylphenol and 4-methylphenol are those components of the phenolic fraction which showed the highest attractiveness on tsetse flies in the experiments. Several mixtures of both methylphenols and/or 1-octen-3-ol were tested as attractants for all three tsetse species.

Natural hosts of Glossina tachinoides (Diptera: Glossinidae) in northern Côte d'Ivoire

Bloodmeal samples of G. tachinoides were taken at the Comoé National Parc in northern Côte d'Ivoire. The total of 1154 identified samples consisted mainly of ruminants (37%, whereof bushbuck represented 57%), hippopotamus (34%), and monitor lizard (19%). These proportions changed with the seasons. In the rainy season the portion of hippopotamus samples increased, whereas that of reptiles decreased. Primate blood was identified only in samples taken in the dry season.

Late pulmonary embolization of a retained pacemaker electrode fragment after attempted transatrial extraction

Embolization of pacemaker electrode fragments into the pulmonary circulation is a rare complication following transvenous pacemaker implantation. One such case is reported here. In a 67-year-old patient, a battery pocket infection developed after transvenous pacemaker implantation and subsequent surgical revision. After removal of the pacemaker and ventricular pacing lead, the atrial lead broke within the superior vena cava when prolonged traction was applied after frustrating attempts to extract the electrode. Attempts to extract the fragment transvenously using endoscopic forceps were unsuccessful. Due to firm fixation of the electrode by extensive fibrous scar tissue in the atrial wall, a further attempt to remove the retained electrode fragment by atriotomy also failed. On the first postoperative day, the fragment migrated to the left pulmonary artery, from where it was successfully extracted by means of a Dormier basket.

Reduction of postoperative donor blood requirement by use of the cell separator

In a prospective, randomized study of 20 patients undergoing elective open-heart surgery, up to c. one-third of the total intraoperative and postoperative transfusion requirement could be provided by autologous centrifuged blood. Retransfusion of washed, packed red blood cells freed from cellular debris, heparin and activated clotting factors significantly reduced blood loss during and after surgery. The cell separator is a valuable aid in autotransfusion technique.

[Ventricle function in low-dose digitoxin in patients with chronic heart failure (stage II/III)]

Using one- and two-dimensional echocardiographic parameters, left ventricular function and dimensions were investigated in 11 patients with chronic heart failure (NYHA stages II-III) and in 10 normal subjects after administration of low-dose digitoxin (0.07 mg). Tests were performed before the begin of therapy, on the 3rd day following rapid saturation, and on the 15th day under maintenance therapy. There was no significant decrease either of heart volume as assessed by X-ray or of enddiastolic volume measured echocardiographically. However--predominantly in patients--a marked decrease in endsystolic diameter (p less than 0.01) and an increase in posterior wall motion amplitude (p less than 0.05) was observed resulting in increased stroke volume, shortening fraction (p less than 0.001). Early diastolic left ventricular filling speed also increased significantly in both groups (p less than 0.01). Changes in these parameters were more pronounced in patients than in normal subjects. In both groups the effects were achieved soon after rapid saturation, increasing slightly during the period of chronic administration of low-dose digitoxin. Parallel to the changes in echocardiographic parameters, a noticeable clinical improvement occurred among patients. No side effects were observed as serum digitoxin levels were in the therapeutic range. It may be concluded that low-dose digitoxin can be employed to increase cardiac contractility in patients with heart failure.

Catheter embolization following median sternotomy

A case of intraoperative internal jugular vein catheter embolization in a patient undergoing median sternotomy for open-heart surgery is described. This complication suggests that right sided cannulation of the internal jugular vein is to be preferred in all patients having a median sternotomy in order to avoid the risk of intersection by median sternotomy.

[Combined use of dihydralazine and nitroglycerin during and after cardiac surgery (author's transl)]

The haemodynamic effect of combined intravenous administration of 18 mg/h dihydralazine and 0.6 mg/h nitroglycerine was examined in the intraoperative and postoperative phases of cardiac surgery (replacement of the aortic and mitral valve or of both valves, and aortocoronary bypass surgery(. Indication for therapy was supplied by a preoperative cardiac index below 2.8 l/min . m2 and an enhanced peripheral resistance above 1200 dyne . sec . cm-5. During a 19-hour observation period the haemodynamic parameters such as cardiac index (+36%) and stroke index (+19%) increased significantly within the investigated group, whereas the peripheral vascular resistance dropped by 16% and the left atrial pressure by 20%. Arterial mean pressure and heart rate did not change. In a patient group treated exclusively with nitroglycerin, the cardiac index decreased (-8%), while the peripheral vascular resistance increased (+6%); an untreated control group showed an increase of the cardiac index by 5%, whereas there was no appreciable change in peripheral vascular resistance and stroke index. The combined use of dihydralazine and nitroglycerin during the perioperative phase of cardiac surgery appears recommendable, since it is possible by such administration to monitor cardiac preload and afterload due to selectivity of the pharmacological sites of action.

[The Haemonetics cell saver in open heart surgery (author's transl)]

A prospective study in 20 patients undergoing open heart surgery showed that up to 48 per cent of the required transfusion volume could be provided by autologous centrifuged blood. Re-transfusion of the washed packed red cells free of cell debris, heparin and aggregate significantly reduced blood loss both during and after the operation. The haemonetics cell saver is a valuable aid in the auto-transfusion technique.

Tissue glue for sealing plastic valves and bioprostheses in the canine aorta

In experiments on seven dogs, a fibrin glue was used to seal plastic valves and bioprostheses in the thoracic aorta. Each valves was fixed in place with only four single sutures. Intraoperative and postoperative angiographic checks, with countercurrent aorta filling, gave no indication of perivalvular leak, even after eight weeks. Histologic studies confirmed the angiographic findings and showed only slight changes in the aortic wall. The results indicate that application of fibrin glue, supplementary to conventional suture procedure, may be useful when satisfactory fixation of aortic valves is hampered by pathologic circumstances.