Electrical remodeling following percutaneous pulmonary valve implantation.

Sudden cardiac death in congenital heart disease is related to increased right ventricular end-diastolic volume (RVEDV), abnormalities of QRS duration, and QRS, JT, and QT dispersions. Surgical pulmonary valve replacement and percutaneous pulmonary valve implantation (PPVI) decrease RVEDV, but the effects of PPVI on surface electrocardiographic parameters are unknown. PPVI represents a pure model of RV mechanical and electrophysiologic changes after replacement. This prospective study sought to determine the effects of PPVI on surface electrocardiographic parameters: Ninety-nine PPVI procedures in patients with congenital heart disease (23.1 ± 10 years of age) were studied before, after, and 1 year after PPVI with serial electrocardiograms and echocardiogram/magnetic resonance images. Forty-three percent had pulmonary stenosis, 27% pulmonary regurgitation (PR), and 29% mixed lesions. In those with predominantly PR (n = 26), QRS duration decreased significantly (135 ± 27 to 128 ± 29 ms, p = 0.007). However, in the total cohort no significant change in QRS duration at 1 year was observed (137 ± 29 to 134 ± 29 ms). Corrected QT interval and QRS, QT, and JT dispersions significantly decreased at 1 year (p ≤0.001). RVEDV correlated with preprocedure QRS duration (r = 0.34, p <0.002) but there was no correlation after PPVI. In conclusion, this is the first study reporting electrical remodeling after isolated PPVI and it confirms that decreases in QRS duration occur after PPVI in PR, as reported for equivalent surgical cohorts. Further, increased homogeneity of repolarization in combination with improved conduction may decrease arrhythmic events in congenital cardiac patients with pulmonary valvular disease.

Percutaneous pulmonary valve implantation: impact of evolving technology and learning curve on clinical outcome.

BACKGROUND: Percutaneous pulmonary valve implantation was introduced in the year 2000 as a nonsurgical treatment for patients with right ventricular outflow tract dysfunction. METHODS AND RESULTS: Between September 2000 and February 2007, 155 patients with stenosis and/or regurgitation underwent percutaneous pulmonary valve implantation. This led to significant reduction in right ventricular systolic pressure (from 63+/-18 to 45+/-13 mm Hg, P<0.001) and right ventricular outflow tract gradient (from 37+/-20 to 17+/-10 mm Hg, P<0.001). Follow-up ranged from 0 to 83.7 months (median 28.4 months). Freedom from reoperation was 93% (+/-2%), 86% (+/-3%), 84% (+/-4%), and 70% (+/-13%) at 10, 30, 50, and 70 months, respectively. Freedom from transcatheter reintervention was 95% (+/-2%), 87% (+/-3%), 73% (+/-6%), and 73% (+/-6%) at 10, 30, 50, and 70 months, respectively. Survival at 83 months was 96.9%. On time-dependent analysis, the first series of 50 patients (log-rank test P<0.001) and patients with a residual gradient >25 mm Hg (log-rank test P=0.01) were associated with a higher risk of reoperations. CONCLUSIONS: Percutaneous pulmonary valve implantation resulted in the ability to avoid surgical right ventricular outflow tract revision in the majority of cases. This procedure might reduce the number of operations needed over the total lifetime of patients with right ventricle-to-pulmonary artery conduits.

Percutaneous pulmonary valve-in-valve implantation: a successful treatment concept for early device failure.

AIMS: Percutaneous pulmonary valve implantation (PPVI) is now an accepted treatment strategy for right ventricular (RV) outflow tract (RVOT) dysfunction in many European Heart Centres. We analysed the efficacy of repeat PPVI as a treatment modality for early device failure. METHODS AND RESULTS: Twenty patients underwent repeat PPVI for RVOT obstruction because of early device failure ('Hammock effect', 'Hammock-like effect', stent fracture, residual stenosis). Repeat PPVI was feasible in all patients with no procedural complications. Following implantation of a second device, catheter-measured RVOT gradient and RV systolic pressure fell significantly (RVOT gradient: 46.1 +/- 3.9 to 18.1 +/- 2.4 mmHg, P < 0.001; RVSP: 70.9 +/- 4.8 to 46.1 +/- 2.6 mmHg, P < 0.001), in all but one patient (15 years, male, common arterial trunk, 11.5 mm homograft). During follow-up, four of 20 required re-intervention [third PPVI for stent fracture (n = 2), device explantation: external compression by the sternum (n = 1), endocarditis (n = 1)], and one of the 20 is awaiting surgical management. In the remainder, second PPVI resulted in a sustained improvement in haemodynamics with a mean follow-up of 10.9 +/- 3.0 months. In this series, the probability of freedom from re-intervention at 2 years was higher after second PPVI when compared with the index procedure (89.4 vs. 20.0%, P < 0.001). CONCLUSION: Repeat PPVI is an effective treatment for early device failure in defined conditions and leads to improved freedom from re-intervention.