Outcome after implantable cardioverter-defibrillator in patients with Brugada syndrome: the Gulf Brugada syndrome registry.

BACKGROUND AND OBJECTIVE: Among patients with Brugada syndrome (BS) and aborted cardiac arrest, syncope, or inducible ventricular fibrillation at electrophysiologic study (EPS), the only currently recommended therapy is an implantable cardioverter-defibrillator (ICD), but these are not without complications. We assessed the total number of shocks (appropriate and inappropriate) and complications related to ICD in patients with BS. METHODS AND RESULTS: Twenty-five patients implanted with ICD for BS in 6 Gulf centers between January 1, 2002, and December 31, 2010, were reviewed. Implantable cardioverter-defibrillator indication was based on aborted cardiac arrest (24%), syncope (56%), or in asymptomatic patients with positive EPS (20%). During a follow-up of 41.2 ± 17.6 months, 3 patients (all with prior cardiac arrest) had appropriate device therapy. Four patients developed complications; 3 of them had inappropriate shocks. CONCLUSION: In our cohort, appropriate device therapy was limited to cardiac arrest survivors, whereas none of those with syncope and/or positive EPS had arrhythmias. Overall complication rate was relatively high, including inappropriate ICD shocks.

Atrioventricular Nodal Re-entrant Tachycardia Ablation: Unusual Function of Slow Pathway.

Slow pathway (SP) ablation is an acceptable, standard method for atrioventricular nodal re-entrant tachycardia (AVNRT) ablation. The exact role of SP in the human heart and the possible negative implications of SP ablation are unknown. The current case report describes an unusual, brief, functional heart block, following radiofrequency ablation of the SP. Our findings highlight the peculiar property of the SP in maintaining conduction over an atrioventricular (AV) node, in circumstances of extreme autonomic imbalance. SP can be ablated without major conduction problems for AVNRT. Careful pre-ablation evaluation of the AV conduction pattern may assist in predicting occurrences of this type of heart block.

Automatic implantable cardioverter defibrillator for the treatment of ventricular fibrillation following coronary artery spasm: a case report.

Coronary artery spasm is an infrequently recognized condition that causes Prinzmetal's angina and specific electrocardiographic changes. A 50-year-old man who suffered a spontaneously aborted acute inferior myocardial infarction is presented. He underwent cardiac catheterization, which initially showed a normal coronary artery. The coronary angiogram was repeated shortly after a second presentation of acute coronary syndrome and ventricular fibrillation. Coronary spasm of very proximal right coronary artery was present, which was reversed completely with intracoronary nitroglycerin. The spasm segment was first stented. Subsequently, an automatic implantable cardioverter defibrillator was inserted because of the uncertainty of future spasm recurrence. The patient was discharged with oral isosorbide dinitrate and Amlodipine. In further follow-up, the patient had two separate shocks within 4 months of implantation. Ventricular fibrillation was the trigger for the shock therapy in both occasions.

Predictive accuracy of tissue Doppler imaging for assessment of noninfarct myocardial region in patients with acute myocardial infarction.

OBJECTIVES: To investigate the value of pulsed tissue Doppler imaging (TDI) in order to predict significant coronary artery stenosis supplying the noninfarct region in patients after acute anterior myocardial infarction. SUBJECTS AND METHODS: Transthoracic echocardiography and coronary angiography were performed on 220 patients with acute anterior myocardial infarction. The TDI-derived variables of the mitral valve annulus in the noninfarct region, systolic velocity (Sm), early diastolic velocity (Em) and late diastolic velocity (Am), were estimated in centimeters per second, and the Em/Am ratio was calculated. RESULTS: Predictive indices revealed that the impaired TDI-derived variables, Sm, Em, Am and the Em/Am ratio, were an indicator for predicting significant coronary stenosis in the noninfarct region. Multivariate analysis revealed that the impaired Sm and Em velocities were significantly associated with age of the patients, coronary collaterals and infarct-related artery stenosis (p < 0.05). Receiver-operating characteristic curve data of TDI-derived variables for prediction of significant coronary stenosis revealed that the cut-off values of Sm, Em, Am and Em/Am ratio were 7.2 cm/s, 6.4 cm/s, 12.1 cm/s and 0.56, respectively. The kappa coefficient value indicated that there was an agreement between coronary angiography and the TDI-derived variables Sm, Em, Am and Em/Am ratio in noninfarct regions (kappa = 0.770, 0.731, 0.693 and 0.679, respectively). There was a significant correlation between the severity of coronary artery stenosis (independent variable) and impaired Sm and Em/Am ratio (dependent variables), y = 11.5 - 0.05x, r = -0.902, (p < 0.05), and y = - 0.14x + 1.87, r = -0.754, (p < 0.05), respectively. CONCLUSION: TDI can be used to identify patients with significant stenosis of the coronary arteries supplying the noninfarct region and consequently may be helpful in considering patients for coronary angiography in the early postinfarction period.

Successful implantation of a permanent pacemaker through a persistent left superior vena cava.

We present a case of successful implantation of a permanent pacemaker through an unusual course of a persistent left superior vena cava (PLSVC). A young male patient presented with symptomatic bradycardia and a heart rate of 35 beats per minute. The pacing lead was introduced through the standard left subclavian vein approach and was found to pass through an unusual course that was suspected to be a PLSVC. The lead was further advanced to the right atrium and positioned successfully in the right atrial appendage with excellent short-term and long-term pacing parameters. PLSVC should be suspected whenever the catheter takes an unusual position during central venous catheterization. Most right heart catheterization procedures, including permanent pacemaker implantation, can be safely completed in spite of this anomaly.