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FUNDAMENTO: O levosimendan, um sensibilizador de cálcio, aumenta a sensibilidade do coração para o cálcio, aumentando assim a contratilidade miocárdica, sem aumento do cálcio intracelular. Recentemente foi demonstrado que o levosimendan era benéfico na melhoria da função renal. No entanto, fica por determinar que o efeito benéfico esteja relacionado em forma diferencial ao status renal durante o evento-índice. OBJETIVO: O objetivo do presente estudo foi determinar se o levosimendan pode melhorar o resultado renal em pacientes com insuficiência cardíaca aguda descompensada com e sem agravamento da função renal. MÉTODOS: Quarenta e cinco pacientes consecutivos que tiveram uma taxa de filtração glomerular reduzida e pelo menos dois dados consecutivos quanto à função renal, antes da administração de levosimendan, foram incluídos no estudo. Os pacientes foram classificados em dois grupos, com e sem agravamento da função renal com base no aumento da creatinina sérica > 0,3 mg/dL. RESULTADOS: Uma melhoria significativa foi observada na função renal em pacientes com agravamento da função renal (creatinina sérica de 1,4 ± 0,16 a 1,21 ± 0,23 mg/dL, p = 0,001 e taxa de filtração glomerular de 48,9 ± 15 a 59,3 ± 21,8 mL/min/m², p = 0,011), apesar de que não houve melhoria significativa em aqueles sem agravamento da função renal (creatinina sérica de 1,29 ± 0,33 a 1,37 ± 0,66 mg/dL, p = 0,240 e taxa de filtração glomerular de 53,7 ± 17,6 a 52,9 ± 21,4 mL/min/m², p = 0,850). CONCLUSÃO: O levosimendan parece proporcionar um efeito de realce renal em pacientes com severa insuficiência cardíaca sistólica descompensada aguda e agravamento da função renal. Considerar esse efeito diferencial poderia contribuir a obter resultados renais benéficos. (Arq Bras Cardiol. 2012; [online].ahead print, PP.0-0)

FUNDAMENTO: A levosimendana é um novo agente inotrópico que aumenta a contratilidade cardíaca sem aumentar a captação celular de cálcio, de forma a não causar sobrecarga de cálcio e arritmias relacionadas. Em pacientes com insuficiência cardíaca (IC), a duração prolongada do QRS está associada com um aumento no risco de mortalidade e morte súbita cardíaca. Mudanças estruturais no ventrículo esquerdo podem levar à contração assíncrona, causando atraso de condução e um QRS prolongado no ECG de superfície. OBJETIVO: O objetivo do presente estudo foi comparar os efeitos agudos de levosimendana e dobutamina na duração do QRS em pacientes com IC grave e ritmo sinusal. MÉTODOS: 60 pacientes consecutivos com IC isquêmica foram incluídos no estudo e randomizados em dois grupos para infusão de levosimendana (n=37) ou dobutamina (n=23). 67,2 % eram homens; a média da idade era 66,4 ± 9,2 anos para todos os pacientes. A duração basal do QRS nos grupos levosimendana e dobutamina foi 120,44 ± 23,82 ms vs 116,59 ± 13,80 ms respectivamente. A fração de ejeção do ventrículo esquerdo (FEVE) estava diminuída em ambos os grupos (23,15 ± 8,3 vs 24,56 ± 7,5%). RESULTADOS: No grupo levosimendana, a duração do QRS diminuiu do valor basal para 116,47 ± 24,56 ms (p=0,006), enquanto não houve diferença significante no grupo dobutamina (p=0,605). Ambos os medicamentos causaram um aumento na FEVE, mas este foi significante apenas no grupo levosimendana (27,95 ± 8,9% p=0,003 vs 26,67 ± 7,6%, p=0,315). CONCLUSÃO: O estudo sugere que a administração de levosimendana, mas não de dobutamina, encurta a duração do QRS no ECG de superfície, possivelmente por causar uma contração coletiva nas fibras do músculo do ventrículo esquerdo. A base molecular desse efeito ainda precisa ser esclarecida.

Abstract Introduction  Atrial fibrillation (AF) is the most frequently encountered chronic arrhythmia associated with significant morbidity. It is generally encountered in the elderly, and will presumably become more prevalent in the future due to the increasing proportion of the elderly in the population. Major studies on AF have demonstrated no significant difference between rhythm and rate control in terms of mortality. However, young population with new-onset or lone AF, or patients in whom the maintenance of sinus rhythm is a must (due to recurrent thromboembolic events etc.) still gives rise to significant concerns related to the obligatory long-term prophylaxis. The long-term administration of the currently available conventional agents (amiodarone, dofetilide, sotalol, propafenone,flecainide etc.) is considered as a ‘double edged sword’ due to the presence of life-threatening adverse effects including pro-arrhythmia and organ toxicity associated with these agents. Several molecules are being developed for the management of AF. However, only a few novel agents confer promising results with respect to safety and efficacy issues in the major studies. Discussion  Dronedarone is an amiodarone analogue without iodine moiety in its structure, and is similar to amiodarone with regard to its structural and electrophysiological properties. Dronedarone is largely denuded of the potentially life-threatening adverse effects of anti-arrhythmics. Major clinical studies have demonstrated both rhythm and rate-controlling efficacy of dronedarone compared to placebo without any serious adverse effects in patients with AF. However, the ANDROMEDA trial, a large scale study including patients hospitalized for symptomatic congestive heart failure (with severely depressed left ventricular systolic functions) was prematurely terminated due to the increased mortality in the dronedarone arm compared to placebo indicating a lack of safety in this group of patients. Conversely, the recently published ATHENA study (including more than 4,600 high risk patients, but excluding those with severe heart failure) demonstrated a significant reduction in cardiovascular hospitalizations and cardiovascular mortality with dronedarone compared to placebo. In contrast, the DIONYSOS study, comparing dronedarone with amiodarone, demonstrated better safety, but lower efficacy of dronedarone for the maintenance of sinus rhythm in patients with AF. Conclusion  Further clinical trials (including head to head comparison with other conventional anti-arrhythmics) are still required to determine the place of dronedarone in the management of AF. The present review focuses on basic and clinical aspects of dronedarone, a novel agent for the management of AF. [ABSTRACT FROM AUTHOR]

Abstract Background  Levosimendan is a relatively new cardiac inotropic agent with calcium sensitizing activity. This study was conducted to investigate the effects of levosimendan (L) and dobutamine (D) on renal function in patients hospitalized with decompensated heart failure (HF). Method  The present study included 88 consecutive patients hospitalized with acutely decompensated HF (New York Heart Association (NYHA) Class 3–4) requiring inotropic therapy. Patients were randomized 2:1 to either L or D for intravenous inotropic support. Diuretic therapy was kept constant during infusions. Renal function values, including serum creatinine (CR), blood urea nitrogen, 24-h urinary output levels and calculated glomerular filtration rate (GFR) were measured just prior to and 24 h after the infusions in all patients, and 48 and 72 h after the infusions in every second patient in both groups. The pre and post-infusion values of renal function and left ventricular ejection fraction (LVEF) were evaluated. Results  LVEF increased significantly in both groups. Those in L showed a significant improvement in calculated GFR after 24 h, whereas those in D showed no significant change (median in change in L:.3%, median change in D: −1.33%). Furthermore, in the L group a significant improvement was observed in calculated GFR after 72 h compared to baseline levels, whereas in D no significant change (median change in L:.45%, median change in D: .09%) was seen. Both agents improved 24-h urinary output. Conclusion  Levosimendan seems to provide beneficial effects in terms of improvement in renal function compared to dobutamine in patients with heart failure who require inotropic therapy. [ABSTRACT FROM AUTHOR]

Abstract Objective  To investigate the relationship between coronary tortuosity and impaired left ventricular relaxation. Methods  One hundred and four subjects who underwent coronary angiography were included in the study. Left anterior descending, left circumflex, and right coronary arteries were traced. Tortuosity was identified by the finding of ≥3 bends (defined as ≥45� change in vessel direction) along main trunk of at least one artery. Study population were divided into tortuosity (n = 54) and no tortuosity (n = 50) groups. Subjects were all submitted to pulsed-wave Doppler and two-dimensional echocardiographic examination to assess left ventricular functions. Results  For subjects with tortuosity, early transmitral inflow (E) velocity was lower, late transmitral inflow (A) velocity was higher, E/A ratio was smaller compared with subjects without tortuosity (P P P = 0.01 and P = 0.005). There was an inverse correlation between total number of arteries with tortuosity and E/A ratio (r = −0.750, P r = 0.723, P r = 0.703, P  Conclusions  This study depicts that coronary tortuosity is associated with impaired left ventricular relaxation.Thus, coronary tortuosity might be an indicator of impaired left ventricular relaxation. [ABSTRACT FROM AUTHOR]

Abstract  Myxoma is the most frequently encountered primary tumour of the heart, comprising more than 50% of all benign cardiac tumours. The case presented here was diagnosed as having dextrocardia with situs inversus and concomitant left ventricular outflow tract myxoma which has been very rarely encountered, particularly consistent with the scarcity of reported cases. [ABSTRACT FROM AUTHOR]

The Thrombolysis in myocardial infarction (TIMI) frame count is a simple clinical tool for assessing quantitative indexes of coronary blood flow. This measurement has been significantly correlated with flow velocity measured with a flow-wire by several investigators during baseline conditions or hyperemia. In this study we aimed to evaluate the coronary flow in patients with isolated coronary artery ectasia by means of the TIMI frame count and to compare the results with those of patients with angiographically normal coronary arteries. The study population consisted of 37 patients with coronary artery ectasia only in the right coronary artery (RCA). The control group consisted of 31 patients with angiographically proven normal coronary arteries. Coronary artery ectasia was defined as nonobstructive lesions of the coronary arteries with a luminal dilatation 1.5-fold or more of the adjacent normal coronary segments. The TIMI frame count was determined for each major coronary artery in each patient according to the methods first described by Gibson et al. The TIMI frame count of RCA in the study group was significantly higher than in that of the control group (51 ± 17 vs 25 ± 8, P « 0.0001). The TIMI frame counts of the study group for the left anterior descending and left circumflex coronary artery were also significantly higher than those of the control group (corrected TIMI frame count for LAD = 42 ± 11 vs 24 ± 7, P « 0.001; TIMI frame count for LCx = 44 ± 15 vs 25 ± 9, P « 0.001). In patients with coronary artery ectasia, the TIMI frame count of the RCA was higher than that of the left anterior descending and left circumflex coronary artery (51 ± 17 vs 42 ± 11 and 44 ± 15, respectively, P « 0.05). We have shown increased TIMI frame counts in patients with isolated coronary artery ectasia and suggest that the pathophysiological mechanism of coronary artery ectasia is not a focal disease. TIMI frame counts can be regarded as an index of the severity of impaired coronary flow in patients with coronary artery ectasia. [ABSTRACT FROM AUTHOR]