Predictors of Complete Heart Block After Alcohol Septal Ablation for Hypertrophic Cardiomyopathy and the Timing of Pacemaker Implantation

Abstract

Catheter-based alcohol septal ablation has recently been introduced for the treatment of left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy. It is associated with various conduction disturbances and may lead to transient or persistent complete heart block (CHB). Electrocardiographic (ECG) changes and predictors of developing CHB and the timing of permanent pacemaker implantation have been variable among the different studies. Among 50 patients studied, we found that a new right bundle branch pattern was the most common new ECG change after septal ablation and that baseline left bundle branch block was strongly associated with the development of CHB (P = 0.004); 9 patients (18%) required permanent pacemaker implantation of whom 7 (78%) remained pacemaker dependent at 14 days with no delayed recovery of atrioventricular conduction. This favors an early pacemaker implantation strategy.

Septal Ablation and Hypertrophic Obstructive Cardiomyopathy: 7 Years US Experience

“…This compares well with most recently published data on SA, which noted post‐procedural pacemaker implantation rate of ∼10% . This has again seen a decline over the last decade plausibly with improving experience, use of myocardial contrast echocardiography to better localize the septal perforators and lesser alcohol dosages . A significant lower rate of permanent pacemaker insertion was noted in the highest hospital volume tertile in our study.…”

“…21 This has again seen a decline over the last decade plausibly with improving experience, use of myocardial contrast echocardiography to better localize the septal perforators and lesser alcohol dosages. 21,22 A significant lower rate of permanent pacemaker insertion was noted in the highest hospital volume tertile in our study. We however lacked data on baseline electrocardiogram abnormalities and intra-procedural details (alcohol volume used etc.).…”

Three Achilles’ heels of alcohol septal ablation

“…Девяти пациентам (18%) был имплантирован постоянный ЭКС. Наиболее зна-чимым предиктором полной АВ-блокады стало наличие дооперационной полной блокады левой ножки пучка Гиса [10].…”

Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy

“…Most commonly, however, ASA causes a transient or permanent disruption of the conduction system: first degree AV block develops in 53% of patients while RBBB block in 46% and complete heart block (CHB) requiring permanent pacemaker (PPM) implantation in 10.5% of patients. Interestingly, CHB may be a transient phenomenon in 10 to 46% of patients with recovery within the first 24 hours [23, 24], while few patients might develop CHB up to nine days after ASA [11, 25]. This may have an important impact on post-procedural care.…”

“…Several studies evaluated determinants of complete heart block after ASA in an effort to identify a high risk group that would benefit from a PPM implantation prior to the procedure. While age >55, female gender, bolus injection of alcohol, injection of more than one septal perforator, volume of alcohol injection and lack of use myocardial contrast echocardiographic localization are all potential factors, only the presence of LBBB on baseline ECG has been persistently identified as a strong predictor of CHB [11, 23, 27, 28]. Faber et al proposed a scoring system based on electrocardiographic markers of abnormal AV conduction (PQ interval, QRS duration and baseline heart rate), the severity of the LVOT gradient, reversibility of CHB, and timing of the SGOT peak.…”