Is pre-operative anaemia a risk marker for in-hospital mortality and morbidity after valve replacement?

AIMS: To assess the level of pre-operative haemoglobin (HB) as a risk marker for morbidity and mortality in the early post-operative period of patients who underwent elective valve replacement. METHODS AND RESULTS: Between January 1998 and March 2004, clinical and outcomes data were collected for the 201 patients who had elective valve replacement. For each gender, the criterion to choose the best cut-off point was that which achieved the maximum likelihood after several General Additive Model models performed in a Bootstrap procedure. The best cut-off point obtained for pre-operative HB was 12 g/dL. Overall peri-operative mortality (deaths occurring during hospital period or within 30 days) was 9.5%. After adjusting well-known independent pre-operative risk factors for operative mortality, pre-operative HB <12 g/dL was identified as an independent predictor for in-hospital mortality (OR, 3.23; 95% CI, 1.09-9.55; P = 0.03). Also adjusting for EuroScore, pre-operative HB remained significant (OR, 3.64; 95% CI, 1.32-10.06; P = 0.01). The same model was applied to post-operative morbidity, and pre-operative HB <12 g/dL was identified as an independent predictor with and without EuroScore (OR, 4.67; 95% CI, 2.03-10.71; P < 0.001), (OR, 5.18; 95% CI, 2.18-12.3; P < 0.001), respectively. CONCLUSION: In patients undergoing elective valve replacement pre-operative HB <12 g/dL is a risk marker of in-hospital mortality and serious adverse outcomes.     

Duration of symptoms and the effects of a more aggressive surgical policy: two factors affecting prognosis of infective endocarditis

One hundred and six patients were analysed in order to assessthe effect of a more aggressive surgical policy in relationto the delays in diagnosis of infective endocarditis. The averageduration of symptoms before diagnosis was 9.7 weeks, even thoughthe patients had sought medical advice at a relatively earlystage of their illness (2.2 weeks). Three of the 29 (10.3%)patients who were treated surgically died and all three wereoperated upon five weeks or later after diagnosis. Seventy-sevenpatients did not have surgery and 15 died (19.5%). The outcome of surgical treatment for prosthetic valve endocarditiswas no worse than for native valve endocarditis. The mortalityof prosthetic valve endocarditis including early infectionswas 32% with medical but only 10% with surgical management comparedwith 14.5% and 10.5% in native valve endocarditis.Endocarditiscannot always be prevented but earlier diagnosis would reducemortality and prevent complications. When medical treatmentis failing then surgery should be considered early and urgentlyparticularly in staphylococcal infection or when large mobilevegetations are recognized; surgery is mandatory in fungal endocarditis.Earlier diagnosis would greatly reduce the current high incidenceof surgery, but that depends on a much heightened index of suspicionamongst both general practitioners and hospital physicians.     

Exclusion of an isolated iliac artery aneurysm using a bifurcated endograft following failed covered stent exclusion.

Endovascular exclusion with covered stents is an alternative to surgical repair of iliac artery aneurysms (IAAs). We report a case where covered stent implantation failed to exclude an IAA, as demonstrated by persistent endoleak. The aneurysm was successfully excluded with a bifurcated aortoiliac endograft. This option should be considered for endovascular treatment of IAAs.     

Endocardite por Trichosporon beigelii 11 anos após cirurgia de troca valvar mitral

Trichosporon beigelii is a non‐pathogenic fungus that can however become an opportunist agent of disseminating and potentially fatal infections, especially in immunocompromised patients. In the literature, there are only 11 published cases of infective endocarditis due to T. beigelii. Most of these cases involved immunocompetent individuals and the main risk factor was the presence of a prosthetic valve. The longest interval between surgery and endocarditis was eight years. In the present study, a case of prosthetic valve endocarditis due to T. beigelii is reported in an immunocompetent patient 11 years after mitral valve replacement. As with similar cases, low clinical suspicion and negative blood cultures delayed the beginning of antifungal therapy and cardiac surgery. Considering the high mortality and severity of T. beigelii endocarditis, it should be considered when there is a prosthetic valve infection with negative blood cultures, irrespective of the time elapsed since the previous surgery.     

Direct inhibition of rat leydig cell function by tamoxifen

The effects of tamoxifen on rat testicular steroidogenesis were studied using dispersed interstitial cells. Tamoxifen significantly inhibited LH-, and 8-bromo-adenosine 3′,5′-monophosphate (8-bromo-cyclic AMP)-stimulated testosterone synthesis in a dose-dependent manner. Tamoxifen (10^?5M) also reduced LH-stimulated cyclic AMP formation. The addition of equimolar concentrations of 17β-estradiol or tamoxifen separately to interstitial cells resulted in similar inhibition of LH-stimulated testosterone synthesis. When equimolar concentrations of 17β-estradiol and tamoxifen were added concomitantly to interstitial cells, the inhibition was additive. Present studies demonstrate that tamoxifen has direct inhibitory effects on testicular steroidogenesis: both at the plasma membrane resulting in decreased cyclic AMP formation and also at steps subsequent to cyclic AMP.     

Recent studies on the chemistry of human, bovine and porcine parathyroid hormones

The amino acid sequence of the NH₂-terminal 34 residues of human parathyroid hormone (PTH) has been determined and duplicated synthetically to produce a peptide that is biologically active. In the amino acid sequences of the bovine and porcine hormones, the glutamic acid function at position 22 has been revised to glutamine. Among these initial 34 residues, human PTH differs from bovine PTH by 5 residues and from porcine PTH by 4 residues. Native human PTH and the synthetic human PTH (1–34) peptide are not rigid structures, and significant changes in conformation were observed during pH titration. In addition, at physiologic pH, native human PTH appeared to differ in structure from human PTH (1–34) in the region of the tryptophan residue (residue 23). The fluorescence spectrum of human PTH revealed a maximum at 344 nm, but the spectrum of human PTH (1–34) had a peak at 343 nm; the spectrum of human PTH (1–34) was normalized to 346 nm in 6 M guanidine hydrochloride, but there was no shift with the intact hormone. Fluorescence titration of human PTH in the alkaline region revealed no loss of tryptophanyl fluorescence in aqueous solution or in 6 M guanidine hydrochloride. The synthetic human PTH (1–34) peptide, however, showed an approximately 25 per cent loss of indole fluorescence during alkaline titration which could be normalized with denaturing reagents. These studies suggest that synthetic fragments of the native hormone may not have the same tertiary conformation as the same sequence in the intact hormone. These findings may be of major significance with regard to the biologic activity and immunologic cross reactivity of synthetic fragments and the native hormone.     

Occult popliteal artery stenosis masquerading as atheroemboli in a patient with previous knee replacement.

The purpose of this article is to report the unusual presentation of a 63-year-old patient with Rutherford grade 2, category 5 tissue ischemic changes involving the right foot secondary to an occult popliteal stenosis that was obscured behind a prosthetic knee on diagnostic angiograms. Conventional abdominal angiography with bilateral lower extremity runoff showed no evidence of significant disease and the patient was misdiagnosed with atheroemboli syndrome secondary to ipsilateral common femoral access following recent catheterization. Ultimately, a meticulous physical examination disclosed a bruit in the right popliteal fossa and selective right leg angiography with oblique views confirmed eccentric complex luminal encroachment in the right popliteal artery that was eclipsed by a prosthetic knee on antecedent nonselective angiography. The lesion responded favorably to endovascular treatment with durable clinical improvement. This case illustrates the importance of a meticulous physical examination and noninvasive studies prior to angiography in patients with ischemic tissue changes and emphasizes the importance of oblique views to image any vessel that may be obscured by a metal prosthesis.     

Early Prosthetic Valve Dysfunction Due to Bioprosthetic Valve Thrombosis: The Role of Echocardiography

Objectives

The purpose of this study was to review the institutional practice of surveillance transthoracic echocardiography (TTE) for diagnosing early prosthetic valve dysfunction (PVD).

Effects of intraoral prosthetics on swallowing in patients with oral cancer

The swallowing patterns of four patients with oral cancer with intraoral palate reshaping/lowering prostheses were studied with and without their prostheses 3 months postoperatively. The prostheses resulted in improved swallow efficiency, increased duration of tongue contact to the pharyngeal wall, and improved speed of movement of the bolus from the valleculae to the pyriform sinus. These results emphasize the effects of the tongue on the pharyngeal as well as oral stage of the swallow.     

Thrombolytic therapy for a thrombosed bjork-shiley tricuspid valve prosthesis

Summary: A 67-year-old man in whom mitral and tricuspid Bjork-Shiley tilting disc prostheses had been implanted 68 months previously presented with thrombotic obstruction of his tricuspid prosthesis. Initial cardiac catheterization demonstrated a significant transprosthetic tricuspid diastolic gradient (9.5 mmHg) with a calculated prosthetic valve orifice area (0.62 cm²) indicating a critical degree of stenosis. The resting cardiac index was markedly reduced (1.5 l/m²/min). Following an intravenous infusion of streptokinase for 66 hours, repeat cardiac catheterization revealed a 50% reduction in transprosthetic diastolic gradient across the tricuspid valve (4.7 mmHg), a greater than fourfold increase in prosthetic valve orifice area (2.87 cm²) with a normal resting cardiac index (3.1 1/m²/min).