Cryoablation of atrial fibrillation in cardiac surgery: outcomes and myocardial injury biomarkers.

OBJECTIVE: Elevations of myocardial injury biomarkers after cardiac surgery without ablation of atrial fibrillation (AF) are related to perioperative myocardial ischemia and associated with an increased risk of mortality and cardiac events. However, there have not been any studies that examined the release of cardiac biomarkers after AF cryoablation procedures with concomitant cardiac surgery. The authors determined the levels of these biomarkers for 2 different procedures involving cryoablation and assessed their clinical implications. DESIGN: A prospective cohort study with cardiac surgical patients. SETTING: A tertiary care university hospital. PARTICIPANTS: One hundred fifty-two cardiac surgical patients. INTERVENTIONS: Patients underwent 1 of 2 different cryoablation approaches: the modified Cox-Maze (CM) III procedure (n = 63) or the isolated left atrial (LA) maze procedure (n = 89). Plasma levels of cardiac biomarkers were measured at 1, 6, 12, and 24 hours after surgery. Twenty-four-hour Holter monitoring was performed at 1 month and 1 year after surgery. MEASUREMENTS AND MAIN RESULTS: Both groups reached very high peak levels of CPK-MB (CM group, 368 ± 171.4 ng/mL and LA group, 203 ± 86.4 ng/mL) and troponin T (CM, 8 ± 4.5 ng/mL and LA, 3.4 ± 2.4 ng/mL). The CPK, CPK-MB, and troponin T levels were significantly higher in the modified CM group compared with the LA maze group. In the first 24 hours after surgery, the average CPK-MB and troponin T values were 78.2 ng/mL higher and 2.3 ng/mL higher, respectively, in the CM group compared with the LA group. In both groups, 79% of the patients remained free of AF at 12 months after surgery. CONCLUSIONS: Cryoablation in cardiac surgery causes the release of very high levels of myocardial injury biomarkers. The modified CM lesion causes a greater elevation of serum biomarker levels than the isolated LA maze procedure, but this increase does not seem to have an adverse effect on rhythm or overall outcome. Cryoablation is a safe and effective surgical treatment for AF.

Update in cardiac arrhythmias and pacing.

This article discusses the main advances in cardiac arrhythmias and pacing published between 2013 and 2014. Special attention is given to the interventional treatment of atrial fibrillation and ventricular arrhythmias, and on advances in cardiac pacing and implantable cardioverter defibrillators, with particular reference to the elderly patient.

[Familial dilated cardiomyopathy in patients transplanted for idiopathic dilated cardiomyopathy]. / Miocardiopatía dilatada familiar en pacientes trasplantados por miocardiopatía dilatada idiopática.

OBJECTIVE: To evaluate the prevalence, clinical features, and pattern of inheritance of familial dilated cardiomyopathy (DCM) in heart transplant patients. PATIENTS AND METHOD: Patients with idiopathic DCM who had undergone heart transplantation were invited to participate. Patients with alcohol abuse were excluded. A clinical evaluation, 12-lead ECG, echocardiogram, blood tests, and DNA extraction were performed in patients and relatives. Familial DCM was defined as the presence of at least one relative with idiopathic DCM. Possible familial DCM was considered when at least one relative had left ventricular enlargement (LVE) (> 112% predicted LVEDD). RESULTS: One hundred and ninety-nine relatives of 43 families were studied. DCM was familial in 11 probands (25.6%) and possibly familial in 11 (25.6%). Fifteen relatives had DCM (7.5%), 26 (13.1%) LVE, and 5 (2.5%) hypertrophic cardiomyopathy. The pattern of inheritance was autosomal dominant in most families. Five probands (3 with familial DCM) had antecedents of consanguinity and possible recessive inheritance. Six probands (14%, 1 with familial DCM) had relatives with conduction system defects. Creatine kinase was moderately increased in 9 relatives (4.5%), 3 of them with LVE. Fifteen patients had at least moderate alcohol intake. Three of them had familial DCM (relatives without alcohol abuse) and 6 had possible familial DCM. CONCLUSIONS: The prevalence of familial DCM is high in patients who undergo heart transplant. Left ventricular enlargement, conduction system abnormalities, and elevated creatine kinase may be early markers of familial disease. Hypertrophic cardiomyopathy is present in some relatives of patients with idiopathic DCM. Familial DCM is present in patients with a previous diagnosis of alcoholic DCM.

p.D1690N Nav1.5 rescues p.G1748D mutation gating defects in a compound heterozygous Brugada syndrome patient.

BACKGROUND: We identified 2 compound heterozygous mutations (p.D1690N and p.G1748D) in the SCN5A gene encoding cardiac Na(+) channels (Nav1.5) in a proband diagnosed with Brugada syndrome type 1. Furthermore, in the allele encoding the p.D1690N mutation, the p.H558R polymorphism was also detected. OBJECTIVE: The purpose of this study was to analyze the functional properties of the mutated channels as well as the putative modulator effects produced by the presence of the polymorphism. METHODS: Wild-type and mutated human Nav1.5 channels were expressed in Chinese hamster ovary cells and recorded using whole-cell patch-clamp technique. RESULTS: Separately, both p.D1690N and p.G1748D mutations produced a marked reduction in peak Na(+) current density (>80%), mainly due to their limited trafficking toward the membrane. Furthermore, p.G1748D mutation profoundly affected channel gating. Both p.D1690N and p.G1748D produced a marked dominant negative effect when cotransfected with either wild-type or p.H558R channels. Conversely, p.H558R was able to rescue defective trafficking of p.D1690N channels toward the membrane when both polymorphism and mutation were in the same construct. Surprisingly, cotransfection with p.D1690N, either alone or together with the polymorphism (p.H558R-D1690N), completely restored the profound gating defects exhibited by p.G1748D channels but only slightly rescued their trafficking. CONCLUSIONS: Our results add further support to the hypothesis that Nav1.5 subunits interact among them before trafficking toward the membrane and suggest that a missense mutation can "rescue" the defective gating produced by another missense mutation.

Preoperative statin treatment reduces systemic inflammatory response and myocardial damage in cardiac surgery.

OBJECTIVE: To determine if preoperative statin treatment is associated with a reduction in systemic inflammatory response (SIR) and myocardial damage markers following cardiac surgery with cardiopulmonary bypass (CPB). METHODS: We study a prospective cohort of 138 patients who underwent coronary and valvular surgery with CPB. We differentiate two study groups: patients with (group A, n=72) or without (group B, n=66) statins. Plasma levels of pro-inflammatory interleukins (tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, IL-8 and IL-2R), creatine phosphokinase (CPK), CPK-MB and troponin I were measured before and 1, 6, 24 and >72 h after surgery. RESULTS: The baseline, operative and postoperative morbidity and mortality characteristics were similar for both the groups. Group A had significantly lower postoperative levels of IL-6 than group B at 6h (68.8+/-5 pg ml(-1) vs 108.9+/-108 pg ml(-1), p=0.01), 24h (71.7+/-7 pg ml(-1) vs 110.4+/-106 pg ml(-1), p=0.01) and before hospital discharge (21.6+/-12 pg ml(-1) vs 32.8+/-27 pg ml(-1), p=0.005), as well as significantly lower average IL-6 levels in the first 24h following surgery (71.8+/-5 pgml(-1) vs 112.8+/-82 pg ml(-1), p=0.002). The postoperative CPK-MB at 24h (19.7+/-23 ng ml(-1) vs 33.1+/-32 ng ml(-1), p=0.02) and troponin I levels at the end of the intervention (2.2+/-2.2 ng ml(-1) vs 3.3+/-3.1 ng ml(-1), p=0.03) and at 24h (4.1+/-3.5 ng ml(-1) vs 6.6+/-8 ng ml(-1), p=0.04) were also significantly lower in the group treated with statins prior to surgery. CONCLUSIONS: Preoperative treatment with statins is associated with a lower biochemical parameters of SIR and myocardial damage following cardiac surgery with CPB, regardless of it being coronary bypass grafting (CABG) or valvular surgery.

[Value of resting and exercise mitral regurgitation during exercise echocardiography to predict outcome in patients with left ventricular dysfunction]. / Valor pronóstico de la regurgitación mitral en reposo y ejercicio durante la ecocardiografía de ejercicio en pacientes con disfunción ventricular izquierda.

INTRODUCTION AND OBJECTIVES: The relative value of exercise echocardiography (EE) over resting echocardiography when this last incorporates information on mitral regurgitation (MR) is unknown. Furthermore, limited data exists regarding to the value of MR worsening during exercise in patients with LV dysfunction. We investigated whether: a) EE has incremental value over a resting echo-Doppler study; and b) post-exercise MR increments the value of EE for predicting outcome in patients with LV dysfunction. METHODS: 388 consecutive patients with LV dysfunction (LV ejection fraction <50%) were followed for 2.1 (1.5) years. There were 46 hard events (myocardial infarction in 10 and cardiac death in 36). RESULTS: There were 43 events in 319 patients with abnormal EE vs 3 events in 69 patients with normal EE (13% vs 4%, P=.04), whereas there were 20 events in the 103 patients with at least moderate resting MR vs 26 events in the 288 with no/mild MR (19% vs 9%, P=.006). Resting MR, peak heart rate x blood pressure, and n masculine of diseased territories on EE were independently associated to hard events. The same variables and MR worsening were independently associated to cardiac death. CONCLUSIONS: EE maintains its higher prognostic value over resting echocardiography even when this last incorporates information on MR. MR worsening increments the value of EE for predicting cardiac death in patients with LV dysfunction.

Importancia de la posición natural de la cabeza / Importance of the natural head position

Se obtiene un procedimiento simplificado que nos permite producir en el tiempo la posición postural del paciente, logrando de esa manera un mejor estudio comparativo de la evolución de los progresos y finalización del tratamiento, sin intervención del operador