Investigation of Dysynchrony in Patients With Pulmonary Hypertension

This is a two part study of ventricular dysynchrony in patients with pulmonary hypertension.
The first part is an observational study, reviewing routinely obtained clinical information
(such as echocardiograms) to assess whether patients with pulmonary hypertension have
electrical or mechanical dysynchrony. If so, we will proceed to the second part of the study
which will assess whether temporarily pacing the right ventricle, during a clinically
indicated catheterization can acutely improve hemodynamics. We will also gather control data
for phase 1 from clinically indicated echos and ECG's in patients with ASD's (RV volume load)
and in patients who are evaluated for an innocent murmur ( Nl heart). We hope to learn
whether patients with pulmonary hypertension, and compromised right ventricles have
electrical and mechanical dysnchrony. If this is true, it is theoretically possible that
resynchronization (pacing) of the right ventricle could improve hemodynamics, symptoms and
long term outcomes.

Inclusion Criteria:

- Pulmonary artery mean pressure at rest of 25 mm Hg

- Controls (for phase 2) Patients undergoing transcatheter closure of secundum ASD
Patients undergoing echocardiogram and ECG as part of work-up for functional murmur
who have normal intracardiac anatomy

Exclusion Criteria:

- Reversible cause of pulmonary hypertension

- Age < 5 yrs (for phase 2)