Ticagrelor is a potent,direct P2Y12 antagonist with rapid onset of action and intense platelet inhibition,indicated in patients with acute coronary syndromes(ACS).This drug is usually well tolerated,but some patients ...Ticagrelor is a potent,direct P2Y12 antagonist with rapid onset of action and intense platelet inhibition,indicated in patients with acute coronary syndromes(ACS).This drug is usually well tolerated,but some patients experience serious adverse effects:Major bleeding;gastrointestinal disturbances;dyspnoea;ventricular pauses > 3 s.Given the unexpected high incidence of bradyarrhythmias,a PLATO substudy monitored this side effect,showing that ticagrelor was associated with an increase in the rate of sinus bradycardia and sinus arrest compared to clopidogrel.This side effect was usually transient,asymptomatic and not associated with higher incidence of severe atrioventricular(AV) block or pacemaker needs.A panel of experts from Food and Drug Administration did not consider bradyarrhythmias a serious problem in clinical practice and,accordingly,current labeling of the drug does not give any precaution or contraindication regarding this issue.However,recently some articles have described ACS patients with high-degree,life-threatening,AV block requiring drug discontinuation and,in some cases,pacemaker implantation.In this paper,we describe and discuss five published case reports of severe AV block following ticagrelor therapy and two other cases managed in our Hospital.The analysis of literature suggests that,although rarely,ticagrelor can be associated with lifethreatening AV block.Caution and careful monitoring are required especially in patients with already compromised conduction system and/or treated with AV blocking agents.Future studies,with long-term rhythm monitoring,would help to define the outcome of patients at higher risk of developing this complication.展开更多
Cardiac magnetic resonance(CMR) is a non-invasive,nonionizing,diagnostic technique that uses magnetic fields,radio waves and field gradients to generate images with high spatial and temporal resolution.After administr...Cardiac magnetic resonance(CMR) is a non-invasive,nonionizing,diagnostic technique that uses magnetic fields,radio waves and field gradients to generate images with high spatial and temporal resolution.After administration of contrast media(e.g.,gadolinium chelate),it is also possible to acquire late images,which make possible the identification and quantification of myocardial areas with scar/fibrosis(late gadolinium enhancement,LGE).CMR is currently a useful instrument in clinical cardiovascular practice for the assessment of several pathological conditions,including ischemic and nonischemic cardiomyopathies and congenital heart disease.In recent years,its field of application has also extended to arrhythmology,both in diagnostic and prognostic evaluation of arrhythmic risk and in therapeutic decisionmaking.In this review,we discuss the possible useful applications of CMR for the arrhythmologist.It is possible to identify three main fields of application of CMR in this context:(1) arrhythmic and sudden cardiac death risk stratification in different heart diseases;(2) decisionmaking in cardiac resynchronization therapy device implantation,presence and extent of myocardial fibrosis for left ventricular lead placement and cardiac venous anatomy; and(3) substrate identification for guiding ablation of complex arrhythmias(atrial fibrillation and ventricular tachycardias).展开更多
Implantable cardioverter defibrillator(ICD) programminginvolves several parameters. In recent years antitachycardia pacing(ATP) has gained an increasing importance in the treatment of ventricular arrhythmias, whether ...Implantable cardioverter defibrillator(ICD) programminginvolves several parameters. In recent years antitachycardia pacing(ATP) has gained an increasing importance in the treatment of ventricular arrhythmias, whether slow or fast. It reduces the number of unnecessary and inappropriate shocks and improves both patient's quality of life and device longevity. There is no clear indication regarding the type of ATP to be used, except for the treatment of fast ventricular tachycardias(188 bpm-250 bpm) where it has been shown a greater efficacy and safety of burst compared to ramp; 8 impulses in each sequence of ATP appears to be the best programming option in this setting. Beyond ATP use, excellent clinical results were obtained with programming standardization following these principles: extended detection time in ventricular fibrillation(VF) zone; supraventricular discrimination criteria up to 200 bpm; first shock in VF zone at the maximum energy in order to reduce the risk of multiple shocks. The MADIT-RIT trial and some observational registries have also recently demonstrated that programming with a widespread use of ATP, higher cut-off rates or delayed intervention reduces the number of inappropriate and unnecessary therapies and improves the survival of patients during mid-term follow-up.展开更多
文摘Ticagrelor is a potent,direct P2Y12 antagonist with rapid onset of action and intense platelet inhibition,indicated in patients with acute coronary syndromes(ACS).This drug is usually well tolerated,but some patients experience serious adverse effects:Major bleeding;gastrointestinal disturbances;dyspnoea;ventricular pauses > 3 s.Given the unexpected high incidence of bradyarrhythmias,a PLATO substudy monitored this side effect,showing that ticagrelor was associated with an increase in the rate of sinus bradycardia and sinus arrest compared to clopidogrel.This side effect was usually transient,asymptomatic and not associated with higher incidence of severe atrioventricular(AV) block or pacemaker needs.A panel of experts from Food and Drug Administration did not consider bradyarrhythmias a serious problem in clinical practice and,accordingly,current labeling of the drug does not give any precaution or contraindication regarding this issue.However,recently some articles have described ACS patients with high-degree,life-threatening,AV block requiring drug discontinuation and,in some cases,pacemaker implantation.In this paper,we describe and discuss five published case reports of severe AV block following ticagrelor therapy and two other cases managed in our Hospital.The analysis of literature suggests that,although rarely,ticagrelor can be associated with lifethreatening AV block.Caution and careful monitoring are required especially in patients with already compromised conduction system and/or treated with AV blocking agents.Future studies,with long-term rhythm monitoring,would help to define the outcome of patients at higher risk of developing this complication.
文摘Cardiac magnetic resonance(CMR) is a non-invasive,nonionizing,diagnostic technique that uses magnetic fields,radio waves and field gradients to generate images with high spatial and temporal resolution.After administration of contrast media(e.g.,gadolinium chelate),it is also possible to acquire late images,which make possible the identification and quantification of myocardial areas with scar/fibrosis(late gadolinium enhancement,LGE).CMR is currently a useful instrument in clinical cardiovascular practice for the assessment of several pathological conditions,including ischemic and nonischemic cardiomyopathies and congenital heart disease.In recent years,its field of application has also extended to arrhythmology,both in diagnostic and prognostic evaluation of arrhythmic risk and in therapeutic decisionmaking.In this review,we discuss the possible useful applications of CMR for the arrhythmologist.It is possible to identify three main fields of application of CMR in this context:(1) arrhythmic and sudden cardiac death risk stratification in different heart diseases;(2) decisionmaking in cardiac resynchronization therapy device implantation,presence and extent of myocardial fibrosis for left ventricular lead placement and cardiac venous anatomy; and(3) substrate identification for guiding ablation of complex arrhythmias(atrial fibrillation and ventricular tachycardias).
文摘Implantable cardioverter defibrillator(ICD) programminginvolves several parameters. In recent years antitachycardia pacing(ATP) has gained an increasing importance in the treatment of ventricular arrhythmias, whether slow or fast. It reduces the number of unnecessary and inappropriate shocks and improves both patient's quality of life and device longevity. There is no clear indication regarding the type of ATP to be used, except for the treatment of fast ventricular tachycardias(188 bpm-250 bpm) where it has been shown a greater efficacy and safety of burst compared to ramp; 8 impulses in each sequence of ATP appears to be the best programming option in this setting. Beyond ATP use, excellent clinical results were obtained with programming standardization following these principles: extended detection time in ventricular fibrillation(VF) zone; supraventricular discrimination criteria up to 200 bpm; first shock in VF zone at the maximum energy in order to reduce the risk of multiple shocks. The MADIT-RIT trial and some observational registries have also recently demonstrated that programming with a widespread use of ATP, higher cut-off rates or delayed intervention reduces the number of inappropriate and unnecessary therapies and improves the survival of patients during mid-term follow-up.
