Cardiology News /Recent Literature Review / Last Quarter 2012
Keywords:
cardiology, electrophysiology, cardiac pacing, newsAbstract
HCS Working Group Seminars will take place in Thessaloniki, 14-16/2/2013
ACC Meeting is slated for San Francisco, 9-11/3/13
HRS Meeting will take place in Denver, 8-11/5/13
EuroPCR to be held in Paris, 21-24/5/13
EuroPace will be held in Athens, 23-26/6/13
ESC Congress will be held in Amsterdam, 31/8-4/9/13
TCT Meeting: San Francisco, 28/10-1/11/13
AHA 2013: Dallas, 16-20/11/13
Metoprolol is not Effective in Long QT Syndromes Types 1 and 2 Compared to Propranolol and Nadolol
The effect of beta blockers was assessed in 382 LQT1/ LQT2 patients (56% female, 27% symptomatic, mean heart rate 76 bpm, mean QTc 472 ms) started on propranolol (n=134), metoprolol (n=147), and nadolol (n=101) at a median age of 14 years. The QTc shortening with propranolol was significantly greater than with other beta-blockers in all patients and in the subset with QTc >480 ms. None of the asymptomatic patients had arrhythmia events. Among symptomatic patients (n=101), 15 had syncope. The QTc shortening was significantly less pronounced among patients with syncope. There was a greater risk of syncope for symptomatic patients initiated on metoprolol compared to users of the other 2 beta-blockers combined, after adjustment for genotype (odds ratio: 3.95, p=0.025). Kaplan-Meier analysis showed a significantly lower event-free survival for symptomatic patients receiving metoprolol compared to propranolol/nadolol. The authors concluded that propranolol and nadolol are significantly more effective than metoprolol in preventing arrhythmic events in symptomatic patients. Also, propranolol was superior to both nadolol and metoprolol in terms of shortening the QTc, particularly in high-risk patients with markedly prolonged QTc. Patients with syncope had significantly less QTc shortening than the event-free patients (Chockalingam P et al, J Am Coll Cardiol 2012;60:2092–2099).
Still Limitations in Subcutaneous ICD
A total of 118 patients (75% males, mean age 50 years) received the entirely subcutaneous implantable cardioverter defibrillator (S-ICD) system. After 18 months of follow-up, 8 patients experienced 45 successful appropriate shocks (98% first shock conversion efficacy). No sudden deaths occurred. Inappropriate shocks occurred in 15 patients (13%), mainly due to T-wave oversensing, mostly solved by a software upgrade and changing the sensing vector of the S-ICD. Complications were noted in 16 patients (14%), more frequently in the first 15 implantations per center. The authors concluded that S-ICD is effective in terminating ventricular arrhythmias, but it has still limitations due to its subcutaneous position. Inappropriate therapy is an important issue in the S-ICD. However, both inappropriate shocks and device-related complications seemed to be related to a learning curve of both the device and the physician (Nordkamp et al, J Am Coll Cardiol 2012;60:1933–1939)... (excerpt)
Downloads
Downloads
Published
Issue
Section
License
Authors who publish with this journal agree to the following terms:
a. Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
b. Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
c. Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
