Fragmentation of the paced QRS complex: a marker of antitachycardia pacing effectiveness among ICD patients.
J Cardiovasc Electrophysiol
; 25(10): 1100-8, 2014 Oct.
Article
em En
| MEDLINE
| ID: mdl-24816219
ABSTRACT
INTRODUCTION:
The presence of notches in the paced QRS complex (P-QRS) from the right ventricular apex (RVA) reflects delays in the activation of the left ventricle and may therefore be associated with longer times of stimulus conduction. Our objective was to determine prospectively the relationship between the duration of a notch ≥0.1 mV in the P-QRS (DN) and the effectiveness of antitachycardia pacing (ATP). METHODS ANDRESULTS:
We followed 286 implantable cardioverter-defibrillator (ICD) patients with left ventricular dysfunction (pacing site RVA) for 41 ± 27 months. ICD programming was standardized. P-QRS (100 bpm) was obtained at implant (50 mm/s). A total of 955 monomorphic ventricular tachycardias (VTs) with a cycle length of 335 ± 32 milliseconds occurred consecutively in 108 patients. ATP was successful in 84% of VTs. DN correlated with the probability of ineffective ATP (C = 0.67; P < 0.001), the cutoff point with the best sensitivity and specificity being 50 milliseconds. The adjusted mean ATP effectiveness per patient was 76% (95% CI 72-85). Patients with a DN ≥ 50 milliseconds had a lower ATP efficiency 67% (56-77) versus 92% (87-97) and a higher proportion of VTs terminated with shocks (SH) 31% (21-42) versus 8% (2-14); P < 0.001 for both. Although the occurrence of VT was similar (41% vs. 40%), the incidence of VT-related SH was higher in patients with a DN ≥ 50 (25% vs. 14%; P = 0.01) in the overall study population (n = 286).CONCLUSIONS:
When ATP is applied to the RVA, a DN ≥ 50 milliseconds is associated with a lower ATP effectiveness and a higher risk of SH due to VT.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Taquicardia
/
Diagnóstico por Computador
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Desfibriladores Implantáveis
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Disfunção Ventricular Esquerda
/
Eletrocardiografia
Tipo de estudo:
Clinical_trials
/
Diagnostic_studies
/
Etiology_studies
Limite:
Aged
/
Female
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Humans
/
Male
Idioma:
En
Revista:
J Cardiovasc Electrophysiol
Assunto da revista:
ANGIOLOGIA
/
CARDIOLOGIA
/
FISIOLOGIA
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Espanha