Norberto Blanco

The Calcium Sensitizer Levosimendan Gives Superior Results to Dobutamine in Postoperative Low Cardiac Output Syndrome

INTRODUCTION AND OBJECTIVES The use of levosimendan to treat postoperative low cardiac output syndrome (LCOS) has been studied in only small patient series and in randomized trials focusing on hemodynamic variables. The objective of the present study was to assess the effectiveness of levosimendan, compared with dobutamine, as a treatment for postoperative LCOS. METHODS Patients with LCOS were randomly assigned to receive either levosimendan (loading dose, 10 microg/kg, followed by 0.1 microg/kg per min for 24 h) or dobutamine (starting dose, 5 microg/kg per min). Hemodynamic and clinical parameters (including postoperative mortality and major complications), the need for the coadministration of another drug (such as an inotrope or a vasopressor) or for balloon counterpulsation, and length of stay in intensive care were all monitored. RESULTS The study included 137 patients: 69 received levosimendan, while 68 were treated with dobutamine. Although both agents improved hemodynamic parameters, the effect of levosimendan was greater and occurred earlier than that of dobutamine. In addition, levosimendan use resulted in lower postoperative mortality (8.7% vs. 25%; P< .05), a lower incidence of major postoperative complications, and less need for an additional inotropic drug (8.7% vs. 36.8%; P< .05), a vasopressor (11.6% vs. 30.9%; P< .05), or balloon counterpulsation (2.9% vs. 14.7%; P<0.05). The length of stay in intensive care was also less (66 vs. 158 h; P< .05). CONCLUSIONS In this randomized study, levosimendan proved more effective than dobutamine. Postoperative morbidity and mortality were lower, fewer patients required either an additional inotropic drug, a vasopressor or intra-aortic balloon counterpulsation, and the length of stay in intensive care was shorter.

Transvenous Extraction of Pacemaker Leads in Infective Endocarditis With Vegetations ≥20 mm: Our Experience

According to published evidence, treatment of infective endocarditis (IE) associated with cardiovascular implantable electronic devices (CIEDs) should include complete removal of the system. Several publications have shown that transvenous removal is an effective and safe nonthoracotomy approach in patients with large vegetations, but experiences with vegetations larger than 20 mm have rarely been reported.

Aneurisma micótico de arteria axilar

Se define como aneurisma micótico la dilatación circunscrita de una arteria, secundaria a una infección de la pared vascular. La diseminación de la infección puede ser intravascular (bacteriemias y embolias sépticas especialmente en la endocarditis infecciosa) o extravascular (focos infecciosos contiguos, como abscesos). La relación entre los aneurismas micóticos y la endocarditis infecciosa fue descrita por primera vez por Osler en 1885 y es una complicación poco frecuente, y más tratándose de la arteria axilar. En la bibliografía mundial sólo se encuentran documentados algunos casos aislados. Se presenta el caso de una mujer de 22 años que ingresó en nuestra institución para estudio de un síndrome febril prolongado. Como antecedentes positivos, refiere prolapso de la válvula mitral. Durante el examen físico se detectó un nuevo soplo intenso de insuficiencia mitral y otros signos periféricos compatibles con endocarditis infecciosa (manchas de Roth, lesiones de Janeway, nódulos de Osler, embolia en miembro superior izquierdo). Los análisis de laboratorio presentaban leucocitosis (el 90% neutrófilos, con formas inmaduras) y eritrosedimentación aumentada. Los hemocultivos fueron 3/3 positivos para Staphylococcus aureus no resistente a meticilina. También se realizó un ecocardiograma transtorácico, en el que se evidenció una vegetación sobre la valva mitral posterior. El ecocardiograma transesofágico mostró válvula mitral de aspecto mixomatoso en la que se observaba, sobre la cara auricular de la base de la valva posterior, imagen multilobulada que ocupaba gran parte de la aurícula izquierda. La paciente fue sometida a reemplazo de válvula mitral con prótesis mecánica (la indicación se fundamentó en el tamaño de la vegetación y múltiples eventos embólicos) y completó su tratamiento antibiótico para su endocarditis infecciosa, evolucionando sin complicaciones. A los 15 días del procedimiento quirúrgico, presentó parestesia-paresia periférica del miembro superior izquierdo (predominantemente radial, confirmada en electromiograma); en el examen clínico se detectó una pequeña masa pulsátil axilar. Se solicitó ecoDoppler arterial y luego una angiografía que evidenciaron un gran aneurisma fusiforme de la arteria axilar izquierda (fig. 1). En primera instancia se intentó la reparación del aneurisma colocando una endoprótesis, pero el procedimiento no tuvo éxito. Por consiguiente, se decidió el tratamiento quirúrgico convencional, con exéresis del aneurisma, liberación del plexo braquial y bypass axilohumeral con vena (fig. 2). La paciente fue dada de alta al cuarto día de la cirugía y tras 1 año de seguimiento no presentó complicaciones. La etiología micótica se fundamentó en el contexto clínico de la paciente, ausencia de traumatismo arterial (incluido el iatrogénico), estudio anatomopatológico posterior con cambios degenerativos e infiltrado leucocitario polimorfonuclear desde la íntima hasta la adventicia. En una revisión bibliográfica encontramos que la fisiopatología de los aneurismas micóticos incluye embolia distal, infección en una lesión arterial preexistente o stent, traumatismo de la pared arterial e infección de un foco contiguo. En cuanto a los gérmenes aislados, cuando el aneurisma se asocia a endocarditis infecciosa, encontramos Staplylococcus aureus y S. epidermidis, Streptococcus viridans y S. faecalis, Pneumococcus y Haemophilus. De ellos, el más frecuentemente aislado es Staphylococcus. Otros gérmenes registrados son Salmonella, Klebsiella y Escherichia coli. Con respecto a la presentación clínica, puede variar desde asintomática —que se detecta por masa pulsátil— hasta afección neurovascular grave por compresión del plexo braquial o eventos embólicos distales. La rotura espontánea suele ser una complicación grave. En los estudios complementarios, la leucocitosis y la eritrosedimentación incrementada son los hallazgos más importantes. Los hemocultivos son positivos CARTAS AL EDITOR

Mycotic axillary artery aneurysm.

A mycotic aneurysm is defined as the limited dilatation of an artery, secondary to an infection of the vascular wall. Spreading of the infection can be intravascular (bacteraemia and septic embolisms especially in infectious endocarditis) or extravascular (contiguous infectious spots, such as abscesses). The relationship between mycotic aneurysms and infectious endocarditis was described for the first time by Osler in 1885 and is a rare complication, especially since it is found in the axillary artery. In the existing literature, only a few isolated documented cases can be found. We present the case of a 22-year-old woman who was admitted to our institution for a study of periodic fever syndrome. Her history shows a mitral valve prolapse. During the physical examination, a new intense murmur from mitral failure was detected and other peripheral signs consistent with infectious endocarditis (Roth spots, Janeway lesions, Osler’s nodes, embolism in the left upper limb). Laboratory analysis presented leukocytosis (90% neutrophils, of immature form) and increased erythrosedimentation. Haemocultures were 3/3 positive for Staphylococcus aureus non-resistant to methicillin. A transthoracic echocardiogram was also carried out, in which there was evidence of vegetation on the posterior mitral valve. The transoesophageal echocardiogram showed the mitral valve with a myxomatous appearance in which, on the atrial wall of the base of the posterior valve, a multilobed image occupying a large portion of the left atrium was observed. The patient underwent mitral valve replacement with a mechanical prosthesis (the decision was based on the size of vegetation and multiple embolic events), and she completed her antibiotic treatment for infectious endocarditis, progressing without complications. Fifty days after surgical procedure, she presented with peripheral paresthesia-paresis in the left upper limb (predominantly radial, confirmed in the electromyogram); in the clinical exam, a small axillary pulsatile mass was detected. An arterial echo-Doppler was requested, and then an angiography, which showed evidence of a large fusiform aneurysm of the left axillary artery (Figure 1). First, the aneurysm was attempted for repair by inserting an endoprosthesis, but the procedure was not successful. Therefore, conventional surgical treatment was decided, with exeresis of the aneurysm, brachial plexus liberation and axillo-humeral bypass with vein (Figure 2). The patient was discharged 4 days after surgery and after 1 year of follow-up, did not present complications. Mycotic aetiology was based on the patient’s symptomatic profile, absence of arterial traumatism (including iatrogenic), subsequent anatomopathologic study with degenerative changes and polymorphonuclear leukocytic infiltrate from the intima to the adventitia. In a bibliographic revision, we found that the physiopathology of mycotic aneurysms includes distal embolism, a pre-existing infection in an arterial lesion, or stent, traumatism of the arterial wall and infection of a contiguous spot. Regarding isolated germs, when the aneurysm is associated with infectious endocarditis, we found Staphylococcus aureus and Staphylococcus epidermitis, Streptococcus viridans and Staphylococcus faecalis, Pneumococcus and Haemophilus. Of these, the most frequently isolated is Staphylococcus.1,2 Other registered germs are Salmonella, Klebsiella, and Escherichia coli. With respect to clinical manifestation, it may vary from asymptomatic—which is detected by pulsatile mass—to serious neurovascular condition due to compression of the brachial plexus or distal embolic events. Spontaneous rupture tends to be a serious complication.3 In the complementary studies, increased leukocytosis and erythrosedimentation are the most important findings. Haemocultures are positive in 50%-70% of patients. Definitive diagnosis of aneurysms can be made through arterial LETTERS TO THE EDITOR

Safety, tolerability and efficacy of ivabradine for control of sinus tachycardia in patients undergoing inotropic therapy

OBJECTIVES: To assess the safety, tolerability and efficacy of ivabradine administered to patients experiencing decompensated heart failure who were undergoing inotropic therapy and developed undesirable sinus tachycardia. METHODS: The present study prospectively included consecutive patients with ischemic-necrotic cardiomyopathy and an ejection fraction <35% who were admitted for decompensated heart failure while undergoing inotropic therapy and developed undesirable sinus tachycardia. Patients experiencing shock, or requiring respiratory or circulatory mechanical support, or those presenting with a heart rhythm other than sinus were excluded. Hemodynamic measurements using a pulmonary artery catheter were performed before and 3 h after an oral dose of 15 mg of ivabradine. Adverse side effects and tolerance were evaluated. RESULTS: The present study included 52 patients (32 men, 20 women) with a mean age of 65.6 years and a mean ejection fraction of 31.5%, who were undergoing inotropic treatment (15 μg/kg). Three hours after ivabradine administration, a reduction in mean (± SD) heart rate from 121±6 beats/min to 98±7 beats/min (P=0.00002) was observed, with an incremental increase in systolic volume from 37.9±5 mL to 47.3±8 mL (P=0.00002) and an increase in cardiac output from 4597±550 mL/min to 4825±535 mL/min (P=0.041). No differences were observed in filling pressures, or systemic or pulmonary resistances. There was good clinical tolerance without hypotension, bradycardia or episodes of atrioventricular block. CONCLUSIONS: Ivabradine proved to be useful and safe for controlling undesirable sinus tachycardia in patients undergoing inotropic treatment.