Use of modified McMaster method for the diagnosis of intestinal helminth infections and estimating parasitic egg load in human faecal samples in non-endemic areas

Summary  A modified McMaster method has been used for the diagnosis and estimating helminth egg load in human faecal samples obtained from random consecutive patients in the areas non-endemic for helminth infections (Slovak Republic, North West Russia). Both positive and negative findings were in a 100 % concordance to those obtained with a reference method accepted in clinical diagnostic laboratories (microscopy of the native stool smear). The McMaster method was efficient in detecting nematode eggs in patients’ stool samples with egg load varying from very low (15–60 epg for T. trichiura) to moderate (1650–4500 epg for A. lumbricoides). Therefore, this method may be successfully (and with a better technical feasibility) used for the diagnosis of intestinal helminth infections in non-endemic areas, with further quantitative analysis of the sample when required.     

At the Cutting Edge of the Impossible: A Tribute to Vladimir P. Demikhov

Vladimir P. Demikhov (1916–1998) performed the world''s first experimental intrathoracic transplantations and coronary artery bypass operation. His successes heralded the era of modern heart and lung transplantation and the surgical treatment of coronary artery disease. Even though he was one of the greatest experimental surgeons of the 20th century, his international isolation fueled speculation, suppositions, and myths. Ironically, his transplantation of a dog''s head drew more publicity than did his pioneering thoracic surgical accomplishments, and he became an easy target for criticism. An account of Demikhov''s life and work is presented herein.Key words: Cardiac surgical procedures/history/methods, coronary artery bypass, Demikhov V, dogs, heart transplantation/history, history of medicine, 20th century, lung transplantation/history, Russia, thoracic surgery, USSR

What I want and aim at is confoundedly difficult, and yet I do not think I aim too high. I want to do drawings which touch some people … I want to progress so far that people will say of my work, he feels deeply, he feels tenderly—notwithstanding my so-called roughness, perhaps even because of it. It seems pretentious to talk this way now, but this is the reason why I want to push on with all my strength. What am I in most people''s eyes? A nonentity or an eccentric and disagreeable man—somebody who has no position in society and never will have, in short, the lowest of the low. Very well … then I should want my work to show what is in the heart of such an eccentric, of such a nobody. This is my ambition, which is, in spite of everything, founded less on anger than on love.¹—Vincent van Gogh (1853–1890)

Vladimir P. Demikhov''s success with experimental coronary artery surgery and intrathoracic organ transplantations heralded the modern era of heart and lung transplantation and the surgical treatment of coronary artery disease. However, Demikhov is known today mainly as a legendary surgeon who experimentally transplanted a second head onto a dog. His international isolation fueled speculation, suppositions, and myths. Although Demikhov''s contributions to cardiothoracic surgery became internationally recognized during recent decades,^2–10 almost no details were known about him. Presented here is the biography of the man behind the legends—one of the greatest experimental surgeons of the 20th century.     

Translocation of Prosthetic Aortic Valve in Advanced Prosthetic Valve Endocarditis

Advanced prosthetic valve endocarditis is often associated with substantial destruction of the tissues adjacent to the prosthesis. Removal of the infected prosthesis and débridement of the infected tissues make implantation of a new prosthesis challenging. Herein, we discuss successful surgical aortic valve translocation in a 50-year-old man who had advanced acute prosthetic valve endocarditis with destruction of the aortic annulus. One year after being discharged from the hospital, the patient was asymptomatic with good exercise tolerance.Key words: Aortic valve, bacterial infections, heart valve diseases/complications/surgery, heart valve prosthesis implantation/methods, hypothermia, induced, postoperative complications/microbiology, reoperation, treatment outcomeAdvanced prosthetic valve endocarditis (PVE) associated with periprosthetic abscess and dehiscence of the prosthesis carries high morbidityand mortality rates.^1,2 Here, we describe the surgical management of apatient who had advanced PVE and a destroyed aortic annulus. The infected prosthesis was removed, and extra-anatomic implantation of a prosthetic aortic valve was performed.     

Extracorporeal Membrane Oxygenation Using the Tandem Heart System's Catheters

We describe the initial—and successful—use of the TandemHeart System''s catheters to provide extracorporeal membrane oxygenation (ECMO), in 2 patients. In 1 patient, who was experiencing severe primary respiratory failure, the catheters provided a standard venovenous ECMO circuit. In the other patient, who had severe, acute pulmonary hypertension and right-heart failure, the catheters enabled a novel right atrial-to-left atrial circuit for ECMO. We discuss the potential of the TandemHeart System''s catheters to provide novel and possibly superior vascular routes for the delivery of ECMO in different types of cardiopulmonary failure.Key words: Extracorporeal circulation, extracorporeal membrane oxygenation/instrumentation/methods, heart failure/therapy, heart-assist devices, hemodynamics, methods, pneumonia/complications, respiratory insufficiency/therapy, technology assessment, biomedical, treatment outcomeExtracorporeal membrane oxygenation (ECMO) first came into wide clinical use as a tool to enable open-heart surgery through cardiopulmonary bypass (CPB) in the 1960s.^1,2 By the 1970s, there was hope that ECMO technology could provide effective temporary oxygenation in patients who had a major, yet reversible, lung injury but in whom mechanical ventilation was not completely effective.³ A generation later, ECMO technology is a well-established, widely used method of support in neonatal and pediatric patients who experience severe respiratory failure.⁴ In contrast, progress in the application of ECMO to improve outcomes of respiratory failure in adults has been much slower. A large National Institutes of Health-sponsored trial of ECMO use in severe respiratory failure of various causes⁵ failed to show a benefit and thereby dampened enthusiasm for this application for more than a decade. New technology and implementation methods, however, have reinvigorated interest in the use of ECMO when severe respiratory failure occurs in adults.^6,7 Indeed, data from the recently completed, large, prospective CESAR trial suggest that ECMO may already be of great usefulness in patients who are experiencing severe respiratory failure.^8–10There have also been encouraging reports of the successful use of ECMO to support patients who are experiencing acute right-heart failure,¹¹ acute refractory left-heart failure,¹² postcardiotomy heart failure,¹³ prolonged cardiac arrest,¹⁴ and postoperative cardiogenic shock.¹⁵ In these circumstances, ECMO has served temporarily (sometimes along with mechanical hemodynamic support) until heart recovery, or as a bridge to heart transplantation, heart–lung transplantation, or the placement of a left ventricular (LV) assist device.The TandemHeart® PTVA® System (CardiacAssist, Inc.; Pittsburgh, Pa) is a new, percutaneously placed, ventricular assist device that has proved to be effective in the short-term management of acute heart failure.¹⁶ The system features innovative vascular-access catheters that enable a minimally invasive approach to mechanical LV assistance. We report here the 1st experience of using these catheters to perform ECMO, in 2 patients. One patient had severe primary respiratory failure, and the other had respiratory failure and right-heart failure caused by severe pulmonary hypertension. The TandemHeart catheters were placed in different intravascular locations in each patient. Our experience suggests that the TandemHeart catheter system can offer innovative and superior options for ECMO delivery to different populations of patients who experience cardiopulmonary failure.     

Clinical implications of left superior vena cava persistence in candidates for pacemaker or cardioverter-defibrillator implantation

Persistence of a left superior vena cava (LSVC) has been reported in 0.3%–0.4% of candidates for pacemaker (PM) or cardioverter-defibrillator (ICD) implantation. The aim of the study was to evaluate the clinical implications of LSVC persistence for proper device performance. We observed the prevalence of LSVC during a 15-year period. A total of 2077 consecutive patients underwent PM implantation over a 15-year period: 7 had persistent LSVCs (0.34%). Among 599 patients undergoing ICD implantation, 4 LSVCs (0.66%) were observed. Overall LSVC persistence was found in 11/2676 (0.41%) patients. The right superior vena cava was absent in 4/11 (36%) patients. The leads were placed from the left subclavian approach in 5/7 PM patients: 2 received an elective right sided approach due to physician preference. All ICD patients had the device placed left pectoral with a single-coil lead: defibrillation therapy was effective in the long term in all but one patient, who required the addition of a subcutaneous array. Left superior vena cava persistence in PM/ICD patients is similar to the general population (0.41% in our study). The left-sided implant may be skill-demanding during lead placement; however, this task can be accomplished in the majority of cases, with a reliable outcome in the short term and appropriate device performance at follow-up.     

Predicting Success and Long-Term Outcomes of Percutaneous Mitral Valvuloplasty: A Multifactorial Score

Background

Percutaneous mitral valvuloplasty (PMV) success depends on appropriate patient selection. A multifactorial score derived from clinical, anatomic/echocardiographic, and hemodynamic variables would predict procedural success and clinical outcome.

Methods

Demographic data, echocardiographic parameters (including echocardiographic score), and procedure-related variables were recorded in 1085 consecutive PMVs. Long-term clinical follow-up (death, mitral valve replacement, redo PMV) was performed. Multivariate regression analysis of the first 800 procedures was performed to identify independent predictors of procedural success. Significant variables were formulated into a risk score and validated prospectively.

Results

Six independent predictors of PMV success were identified: age less than 55 years, New York Heart Association classes I and II, pre-PMV mitral area of 1 cm² or greater, pre-PMV mitral regurgitation grade less than 2, echocardiographic score of 8 or greater, and male sex. A score was constructed from the arithmetic sum of variables present per patient. Procedural success rates increased incrementally with increasing score (0% for 0/6, 39.7% for 1/6, 54.4% for 2/6, 77.3% for 3/6, 85.7% for 4/6, 95% for 5/6, and 100% for 6/6; P < .001). In a validation cohort (n = 285 procedures), the multifactorial score remained a significant predictor of PMV success (P < .001). Comparison between the new score and the echocardiographic score confirmed that the new index was more sensitive and specific (P < .001). This new score also predicts long-term outcomes (P < .001).

Conclusion

Clinical, anatomic, and hemodynamic variables predict PMV success and clinical outcome and may be formulated in a scoring system that would help to identify the best candidates for PMV.     

Ephedrine-induced acute myocardial infarction in a young athlete: a case of thrombus management

A case of acute myocardial infarction in a young athlete provoked by ephedrine abuse has been described in this study. An intracoronary thrombus found in the left anterior descending coronary artery at urgent angiography was successfully removed using the Pronto (Vascular Solutions, Minneapolis, Minnesota) aspiration catheter. The intravascular ultrasound examination performed thereafter showed a nonobstructive atherosclerotic plaque in the culprit artery; there was no evidence whatsoever of possible plaque disruption. The result of percutaneous coronary intervention was satisfactory, and no stent implantation was needed. The patient experienced no adverse events until his outpatient visit 3 months later.     

Molecular remodeling of potassium channels in fibroblasts from centenarians: A marker of longevity?

Aging is a complex process resulting from, among other, dynamic non-linear interactions between genetics and environment. Centenarians are the best example of successful aging in humans, as they escaped from, or largely postponed, major age-related diseases. Ionic fluxes changes play a key role in several patho-physiological cellular processes, but their relation to human aging is largely unexplored. In the present study we have compared patch-clamp potassium (K⁺) current recordings from dermal fibroblasts (DF) obtained from young, elderly and centenarian donors. We found that in DF from elderly donors, but not from centenarians, K⁺ current amplitude is significantly smaller with respect to DF from young donors. Moreover, cell membrane capacitance of DF from elderly donors is smaller with respect to young donors and centenarians. We also observed that the voltage-gated Shaker Kv1.1 channel is expressed in higher percentage of elderly's and centenarian's DF than young's, whereas the large-conductance calcium-activated K⁺ (BK_Ca) channel β1 subunit is expressed in lower percentage of centenarian's DF than in elderly's and young's. The maintenance of “young” K⁺ currents and the peculiar age-related remodeling of K⁺ channel subtypes in centenarian's DF is likely associated with successful aging and might provide a predictive marker of longevity.