Background:
Chronic pulmonary regurgitation (PR) causes progressive right ventricular (RV) dysfunction and heart failure. Parameters defining the optimal time point for surgery of chronic PR are lacking. The present study prospectively evaluated the impact of clinical parameters, cardiorespiratory function and neurohumoral activation on post operative RV function and volumes assessed with magnetic resonance imaging (MRI) after pulmonary valve replacement in patients with severe PR.
Methods and Results:
MRI was performed preoperatively and at follow-up 5.2±3.5months after surgery in 27 patients (23.6±2.9 years, 15 women) with severe PR. Underlying cardiac disease was repaired Tetralogy of Fallot (n=22), Double outlet right ventricle (n=3) and PR after pulmonary valvulotomy (n=2). Postoperatively, RV endsystolic (RVESVI) and enddiastolic volume indices (RVEDVI) decreased significantly (RVESVI pre 78,2±20,4 ml/m
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BSA vs. RVESVI post 52,2±16,8 ml/m
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BSA, p<0,001; RVEDVI pre 150,7±27,7 ml/m
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BSA vs. RVEDVI post 105,7±26,7 ml/m
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BSA; p<0,001). Mean RV ejection fraction (RVEF) remained unchanged in the study cohort (47.6 ± 8.7% vs. 49.7 ±7.0%, n.s.). Preoperative volumes did not correlate with postoperative ejection fraction. With increasing preoperative QRS-duration, postoperative RVEF decreased significantly (r=−0.57; p<0,005). A preoperative QRS-duration smaller than the median (156ms) predicted an improved RVEF as compared to a QRS-duration ≤ 156ms (54.9% vs. 46.8%, p<0.05). Neither elevated NT-proBNP levels nor reduced cardiorespiratory function were able to predict postoperative RVEF.
Conclusion:
Valve replacement in severe pulmonary regurgitation causes significant reduction of RV volumes. Prolonged preoperative QRS-duration was associated with a worse outcome with respect to postoperative RVEF. During follow-up an increase in QRS-duration in patients with chronic PR might indicate deterioration in RV function reflecting a risk of impaired RV function postoperatively.
Reduction of QRS duration after pulmonary valve replacement in adult Fallot patients is related to reduction of right ventricular volume
